4 perl5db.pl - the perl debugger
8 perl -d your_Perl_script
12 C<perl5db.pl> is the perl debugger. It is loaded automatically by Perl when
13 you invoke a script with S<C<perl -d>>. This documentation tries to outline the
14 structure and services provided by C<perl5db.pl>, and to describe how you
17 See L<perldebug> for an overview of how to use the debugger.
21 The debugger can look pretty forbidding to many Perl programmers. There are
22 a number of reasons for this, many stemming out of the debugger's history.
24 When the debugger was first written, Perl didn't have a lot of its nicer
25 features - no references, no lexical variables, no closures, no object-oriented
26 programming. So a lot of the things one would normally have done using such
27 features was done using global variables, globs and the C<local()> operator
30 Some of these have survived into the current debugger; a few of the more
31 interesting and still-useful idioms are noted in this section, along with notes
32 on the comments themselves.
34 =head2 Why not use more lexicals?
36 Experienced Perl programmers will note that the debugger code tends to use
37 mostly package globals rather than lexically-scoped variables. This is done
38 to allow a significant amount of control of the debugger from outside the
41 Unfortunately, though the variables are accessible, they're not well
42 documented, so it's generally been a decision that hasn't made a lot of
43 difference to most users. Where appropriate, comments have been added to
44 make variables more accessible and usable, with the understanding that these
45 I<are> debugger internals, and are therefore subject to change. Future
46 development should probably attempt to replace the globals with a well-defined
47 API, but for now, the variables are what we've got.
49 =head2 Automated variable stacking via C<local()>
51 As you may recall from reading C<perlfunc>, the C<local()> operator makes a
52 temporary copy of a variable in the current scope. When the scope ends, the
53 old copy is restored. This is often used in the debugger to handle the
54 automatic stacking of variables during recursive calls:
59 # Do some stuff, then ...
63 What happens is that on entry to the subroutine, C<$some_global> is localized,
64 then altered. When the subroutine returns, Perl automatically undoes the
65 localization, restoring the previous value. Voila, automatic stack management.
67 The debugger uses this trick a I<lot>. Of particular note is C<DB::eval>,
68 which lets the debugger get control inside of C<eval>'ed code. The debugger
69 localizes a saved copy of C<$@> inside the subroutine, which allows it to
70 keep C<$@> safe until it C<DB::eval> returns, at which point the previous
71 value of C<$@> is restored. This makes it simple (well, I<simpler>) to keep
72 track of C<$@> inside C<eval>s which C<eval> other C<eval's>.
74 In any case, watch for this pattern. It occurs fairly often.
78 This is used to cleverly reverse the sense of a logical test depending on
79 the value of an auxiliary variable. For instance, the debugger's C<S>
80 (search for subroutines by pattern) allows you to negate the pattern
83 # Find all non-'foo' subs:
86 Boolean algebra states that the truth table for XOR looks like this:
92 (! not present and no match) --> false, don't print
96 (! not present and matches) --> true, print
100 (! present and no match) --> true, print
104 (! present and matches) --> false, don't print
108 As you can see, the first pair applies when C<!> isn't supplied, and
109 the second pair applies when it is. The XOR simply allows us to
110 compact a more complicated if-then-elseif-else into a more elegant
111 (but perhaps overly clever) single test. After all, it needed this
114 =head2 FLAGS, FLAGS, FLAGS
116 There is a certain C programming legacy in the debugger. Some variables,
117 such as C<$single>, C<$trace>, and C<$frame>, have I<magical> values composed
118 of 1, 2, 4, etc. (powers of 2) OR'ed together. This allows several pieces
119 of state to be stored independently in a single scalar.
125 is checking to see if the appropriate bit is on. Since each bit can be
126 "addressed" independently in this way, C<$scalar> is acting sort of like
127 an array of bits. Obviously, since the contents of C<$scalar> are just a
128 bit-pattern, we can save and restore it easily (it will just look like
131 The problem, is of course, that this tends to leave magic numbers scattered
132 all over your program whenever a bit is set, cleared, or checked. So why do
139 First, doing an arithmetical or bitwise operation on a scalar is
140 just about the fastest thing you can do in Perl: S<C<use constant>> actually
141 creates a subroutine call, and array and hash lookups are much slower. Is
142 this over-optimization at the expense of readability? Possibly, but the
143 debugger accesses these variables a I<lot>. Any rewrite of the code will
144 probably have to benchmark alternate implementations and see which is the
145 best balance of readability and speed, and then document how it actually
150 Second, it's very easy to serialize a scalar number. This is done in
151 the restart code; the debugger state variables are saved in C<%ENV> and then
152 restored when the debugger is restarted. Having them be just numbers makes
157 Third, some of these variables are being shared with the Perl core
158 smack in the middle of the interpreter's execution loop. It's much faster for
159 a C program (like the interpreter) to check a bit in a scalar than to access
160 several different variables (or a Perl array).
164 =head2 What are those C<XXX> comments for?
166 Any comment containing C<XXX> means that the comment is either somewhat
167 speculative - it's not exactly clear what a given variable or chunk of
168 code is doing, or that it is incomplete - the basics may be clear, but the
169 subtleties are not completely documented.
171 Send in a patch if you can clear up, fill out, or clarify an C<XXX>.
173 =head1 DATA STRUCTURES MAINTAINED BY CORE
175 There are a number of special data structures provided to the debugger by
176 the Perl interpreter.
178 The array C<@{$main::{'_<'.$filename}}> (aliased locally to C<@dbline>
179 via glob assignment) contains the text from C<$filename>, with each
180 element corresponding to a single line of C<$filename>. Additionally,
181 breakable lines will be dualvars with the numeric component being the
182 memory address of a COP node. Non-breakable lines are dualvar to 0.
184 The hash C<%{'_<'.$filename}> (aliased locally to C<%dbline> via glob
185 assignment) contains breakpoints and actions. The keys are line numbers;
186 you can set individual values, but not the whole hash. The Perl interpreter
187 uses this hash to determine where breakpoints have been set. Any true value is
188 considered to be a breakpoint; C<perl5db.pl> uses C<$break_condition\0$action>.
189 Values are magical in numeric context: 1 if the line is breakable, 0 if not.
191 The scalar C<${"_<$filename"}> simply contains the string C<$filename>.
192 This is also the case for evaluated strings that contain subroutines, or
193 which are currently being executed. The $filename for C<eval>ed strings looks
194 like S<C<(eval 34)>>.
196 =head1 DEBUGGER STARTUP
198 When C<perl5db.pl> starts, it reads an rcfile (C<perl5db.ini> for
199 non-interactive sessions, C<.perldb> for interactive ones) that can set a number
200 of options. In addition, this file may define a subroutine C<&afterinit>
201 that will be executed (in the debugger's context) after the debugger has
204 Next, it checks the C<PERLDB_OPTS> environment variable and treats its
205 contents as the argument of a C<o> command in the debugger.
207 =head2 STARTUP-ONLY OPTIONS
209 The following options can only be specified at startup.
210 To set them in your rcfile, add a call to
211 C<&parse_options("optionName=new_value")>.
217 the TTY to use for debugging i/o.
221 if set, goes in NonStop mode. On interrupt, if TTY is not set,
222 uses the value of noTTY or F<$HOME/.perldbtty$$> to find TTY using
223 Term::Rendezvous. Current variant is to have the name of TTY in this
228 if false, a dummy ReadLine is used, so you can debug
229 ReadLine applications.
233 if true, no i/o is performed until interrupt.
237 file or pipe to print line number info to. If it is a
238 pipe, a short "emacs like" message is used.
242 host:port to connect to on remote host for remote debugging.
246 file to store session history to. There is no default and so no
247 history file is written unless this variable is explicitly set.
251 number of commands to store to the file specified in C<HistFile>.
258 &parse_options("NonStop=1 LineInfo=db.out");
259 sub afterinit { $trace = 1; }
261 The script will run without human intervention, putting trace
262 information into C<db.out>. (If you interrupt it, you had better
263 reset C<LineInfo> to something I<interactive>!)
265 =head1 INTERNALS DESCRIPTION
267 =head2 DEBUGGER INTERFACE VARIABLES
269 Perl supplies the values for C<%sub>. It effectively inserts
270 a C<&DB::DB();> in front of each place that can have a
271 breakpoint. At each subroutine call, it calls C<&DB::sub> with
272 C<$DB::sub> set to the called subroutine. It also inserts a C<BEGIN
273 {require 'perl5db.pl'}> before the first line.
275 After each C<require>d file is compiled, but before it is executed, a
276 call to C<&DB::postponed($main::{'_<'.$filename})> is done. C<$filename>
277 is the expanded name of the C<require>d file (as found via C<%INC>).
279 =head3 IMPORTANT INTERNAL VARIABLES
283 Used to control when the debugger will attempt to acquire another TTY to be
288 =item * 1 - on C<fork()>
290 =item * 2 - debugger is started inside debugger
292 =item * 4 - on startup
298 The value -2 indicates that no return value should be printed.
299 Any other positive value causes C<DB::sub> to print return values.
303 The item to be eval'ed by C<DB::eval>. Used to prevent messing with the current
304 contents of C<@_> when C<DB::eval> is called.
308 Determines what messages (if any) will get printed when a subroutine (or eval)
309 is entered or exited.
313 =item * 0 - No enter/exit messages
315 =item * 1 - Print I<entering> messages on subroutine entry
317 =item * 2 - Adds exit messages on subroutine exit. If no other flag is on, acts like 1+2.
319 =item * 4 - Extended messages: C<< <in|out> I<context>=I<fully-qualified sub name> from I<file>:I<line> >>. If no other flag is on, acts like 1+4.
321 =item * 8 - Adds parameter information to messages, and overloaded stringify and tied FETCH is enabled on the printed arguments. Ignored if C<4> is not on.
323 =item * 16 - Adds C<I<context> return from I<subname>: I<value>> messages on subroutine/eval exit. Ignored if C<4> is not on.
327 To get everything, use C<$frame=30> (or S<C<o f=30>> as a debugger command).
328 The debugger internally juggles the value of C<$frame> during execution to
329 protect external modules that the debugger uses from getting traced.
333 Tracks current debugger nesting level. Used to figure out how many
334 C<E<lt>E<gt>> pairs to surround the line number with when the debugger
335 outputs a prompt. Also used to help determine if the program has finished
336 during command parsing.
338 =head4 C<$onetimeDump>
340 Controls what (if anything) C<DB::eval()> will print after evaluating an
345 =item * C<undef> - don't print anything
347 =item * C<dump> - use C<dumpvar.pl> to display the value returned
349 =item * C<methods> - print the methods callable on the first item returned
353 =head4 C<$onetimeDumpDepth>
355 Controls how far down C<dumpvar.pl> will go before printing C<...> while
356 dumping a structure. Numeric. If C<undef>, print all levels.
360 Used to track whether or not an C<INT> signal has been detected. C<DB::DB()>,
361 which is called before every statement, checks this and puts the user into
362 command mode if it finds C<$signal> set to a true value.
366 Controls behavior during single-stepping. Stacked in C<@stack> on entry to
367 each subroutine; popped again at the end of each subroutine.
371 =item * 0 - run continuously.
373 =item * 1 - single-step, go into subs. The C<s> command.
375 =item * 2 - single-step, don't go into subs. The C<n> command.
377 =item * 4 - print current sub depth (turned on to force this when C<too much
384 Controls the output of trace information.
388 =item * 1 - The C<t> command was entered to turn on tracing (every line executed is printed)
390 =item * 2 - watch expressions are active
392 =item * 4 - user defined a C<watchfunction()> in C<afterinit()>
396 =head4 C<$client_editor>
398 1 if C<LINEINFO> was directed to a pipe; 0 otherwise. (The term
399 C<$slave_editor> was formerly used here.)
403 Stack of filehandles that C<DB::readline()> will read commands from.
404 Manipulated by the debugger's C<source> command and C<DB::readline()> itself.
408 Local alias to the magical line array, C<@{$main::{'_<'.$filename}}> ,
409 supplied by the Perl interpreter to the debugger. Contains the source.
413 Previous values of watch expressions. First set when the expression is
414 entered; reset whenever the watch expression changes.
418 Saves important globals (C<$@>, C<$!>, C<$^E>, C<$,>, C<$/>, C<$\>, C<$^W>)
419 so that the debugger can substitute safe values while it's running, and
420 restore them when it returns control.
424 Saves the current value of C<$single> on entry to a subroutine.
425 Manipulated by the C<c> command to turn off tracing in all subs above the
430 The 'watch' expressions: to be evaluated before each line is executed.
434 The typeahead buffer, used by C<DB::readline>.
438 Command aliases. Stored as character strings to be substituted for a command
441 =head4 C<%break_on_load>
443 Keys are file names, values are 1 (break when this file is loaded) or undef
444 (don't break when it is loaded).
448 Keys are line numbers, values are C<condition\0action>. If used in numeric
449 context, values are 0 if not breakable, 1 if breakable, no matter what is
450 in the actual hash entry.
452 =head4 C<%had_breakpoints>
454 Keys are file names; values are bitfields:
458 =item * 1 - file has a breakpoint in it.
460 =item * 2 - file has an action in it.
464 A zero or undefined value means this file has neither.
468 Stores the debugger options. These are character string values.
472 Saves breakpoints for code that hasn't been compiled yet.
473 Keys are subroutine names, values are:
477 =item * C<compile> - break when this sub is compiled
479 =item * C<< break +0 if <condition> >> - break (conditionally) at the start of this routine. The condition will be '1' if no condition was specified.
483 =head4 C<%postponed_file>
485 This hash keeps track of breakpoints that need to be set for files that have
486 not yet been compiled. Keys are filenames; values are references to hashes.
487 Each of these hashes is keyed by line number, and its values are breakpoint
488 definitions (C<condition\0action>).
490 =head1 DEBUGGER INITIALIZATION
492 The debugger's initialization actually jumps all over the place inside this
493 package. This is because there are several BEGIN blocks (which of course
494 execute immediately) spread through the code. Why is that?
496 The debugger needs to be able to change some things and set some things up
497 before the debugger code is compiled; most notably, the C<$deep> variable that
498 C<DB::sub> uses to tell when a program has recursed deeply. In addition, the
499 debugger has to turn off warnings while the debugger code is compiled, but then
500 restore them to their original setting before the program being debugged begins
503 The first C<BEGIN> block simply turns off warnings by saving the current
504 setting of C<$^W> and then setting it to zero. The second one initializes
505 the debugger variables that are needed before the debugger begins executing.
506 The third one puts C<$^X> back to its former value.
508 We'll detail the second C<BEGIN> block later; just remember that if you need
509 to initialize something before the debugger starts really executing, that's
522 BEGIN {eval 'use IO::Handle'}; # Needed for flush only? breaks under miniperl
526 $^V =~ /^v(\d+\.\d+)/;
527 feature->import(":$1");
528 $_initial_cwd = Cwd::getcwd();
531 # Debugger for Perl 5.00x; perl5db.pl patch level:
532 use vars qw($VERSION $header);
534 # bump to X.XX in blead, only use X.XX_XX in maint
537 $header = "perl5db.pl version $VERSION";
539 =head1 DEBUGGER ROUTINES
543 This function replaces straight C<eval()> inside the debugger; it simplifies
544 the process of evaluating code in the user's context.
546 The code to be evaluated is passed via the package global variable
547 C<$DB::evalarg>; this is done to avoid fiddling with the contents of C<@_>.
549 Before we do the C<eval()>, we preserve the current settings of C<$trace>,
550 C<$single>, C<$^D> and C<$usercontext>. The latter contains the
551 preserved values of C<$@>, C<$!>, C<$^E>, C<$,>, C<$/>, C<$\>, C<$^W> and the
552 user's current package, grabbed when C<DB::DB> got control. This causes the
553 proper context to be used when the eval is actually done. Afterward, we
554 restore C<$trace>, C<$single>, and C<$^D>.
556 Next we need to handle C<$@> without getting confused. We save C<$@> in a
557 local lexical, localize C<$saved[0]> (which is where C<save()> will put
558 C<$@>), and then call C<save()> to capture C<$@>, C<$!>, C<$^E>, C<$,>,
559 C<$/>, C<$\>, and C<$^W>) and set C<$,>, C<$/>, C<$\>, and C<$^W> to values
560 considered sane by the debugger. If there was an C<eval()> error, we print
561 it on the debugger's output. If C<$onetimedump> is defined, we call
562 C<dumpit> if it's set to 'dump', or C<methods> if it's set to
563 'methods'. Setting it to something else causes the debugger to do the eval
564 but not print the result - handy if you want to do something else with it
565 (the "watch expressions" code does this to get the value of the watch
566 expression but not show it unless it matters).
568 In any case, we then return the list of output from C<eval> to the caller,
569 and unwinding restores the former version of C<$@> in C<@saved> as well
570 (the localization of C<$saved[0]> goes away at the end of this scope).
572 =head3 Parameters and variables influencing execution of DB::eval()
574 C<DB::eval> isn't parameterized in the standard way; this is to keep the
575 debugger's calls to C<DB::eval()> from mucking with C<@_>, among other things.
576 The variables listed below influence C<DB::eval()>'s execution directly.
580 =item C<$evalarg> - the thing to actually be eval'ed
582 =item C<$trace> - Current state of execution tracing
584 =item C<$single> - Current state of single-stepping
586 =item C<$onetimeDump> - what is to be displayed after the evaluation
588 =item C<$onetimeDumpDepth> - how deep C<dumpit()> should go when dumping results
592 The following variables are altered by C<DB::eval()> during its execution. They
593 are "stacked" via C<local()>, enabling recursive calls to C<DB::eval()>.
597 =item C<@res> - used to capture output from actual C<eval>.
599 =item C<$otrace> - saved value of C<$trace>.
601 =item C<$osingle> - saved value of C<$single>.
603 =item C<$od> - saved value of C<$^D>.
605 =item C<$saved[0]> - saved value of C<$@>.
607 =item $\ - for output of C<$@> if there is an evaluation error.
611 =head3 The problem of lexicals
613 The context of C<DB::eval()> presents us with some problems. Obviously,
614 we want to be 'sandboxed' away from the debugger's internals when we do
615 the eval, but we need some way to control how punctuation variables and
616 debugger globals are used.
618 We can't use local, because the code inside C<DB::eval> can see localized
619 variables; and we can't use C<my> either for the same reason. The code
620 in this routine compromises and uses C<my>.
622 After this routine is over, we don't have user code executing in the debugger's
623 context, so we can use C<my> freely.
627 ############################################## Begin lexical danger zone
629 # 'my' variables used here could leak into (that is, be visible in)
630 # the context that the code being evaluated is executing in. This means that
631 # the code could modify the debugger's variables.
633 # Fiddling with the debugger's context could be Bad. We insulate things as
699 # Used to save @ARGV and extract any debugger-related flags.
702 # Used to prevent multiple entries to diesignal()
703 # (if for instance diesignal() itself dies)
706 # Used to prevent the debugger from running nonstop
710 sub _calc_usercontext {
713 # Cancel strict completely for the evaluated code, so the code
714 # the user evaluates won't be affected by it. (Shlomi Fish)
715 return 'no strict; ($@, $!, $^E, $,, $/, $\, $^W) = @DB::saved;'
716 . "package $package;"; # this won't let them modify, alas
721 # 'my' would make it visible from user code
722 # but so does local! --tchrist
723 # Remember: this localizes @DB::res, not @main::res.
727 # Try to keep the user code from messing with us. Save these so that
728 # even if the eval'ed code changes them, we can put them back again.
729 # Needed because the user could refer directly to the debugger's
730 # package globals (and any 'my' variables in this containing scope)
731 # inside the eval(), and we want to try to stay safe.
732 local $otrace = $trace;
733 local $osingle = $single;
736 # Untaint the incoming eval() argument.
737 { ($evalarg) = $evalarg =~ /(.*)/s; }
739 # $usercontext built in DB::DB near the comment
740 # "set up the context for DB::eval ..."
741 # Evaluate and save any results.
742 @res = eval "$usercontext $evalarg;\n"; # '\n' for nice recursive debug
744 # Restore those old values.
750 # Save the current value of $@, and preserve it in the debugger's copy
751 # of the saved precious globals.
754 # Since we're only saving $@, we only have to localize the array element
755 # that it will be stored in.
756 local $saved[0]; # Preserve the old value of $@
759 # Now see whether we need to report an error back to the user.
765 # Display as required by the caller. $onetimeDump and $onetimedumpDepth
766 # are package globals.
767 elsif ($onetimeDump) {
768 if ( $onetimeDump eq 'dump' ) {
769 local $option{dumpDepth} = $onetimedumpDepth
770 if defined $onetimedumpDepth;
771 dumpit( $OUT, \@res );
773 elsif ( $onetimeDump eq 'methods' ) {
776 } ## end elsif ($onetimeDump)
780 ############################################## End lexical danger zone
782 # After this point it is safe to introduce lexicals.
783 # The code being debugged will be executing in its own context, and
784 # can't see the inside of the debugger.
786 # However, one should not overdo it: leave as much control from outside as
787 # possible. If you make something a lexical, it's not going to be addressable
788 # from outside the debugger even if you know its name.
790 # This file is automatically included if you do perl -d.
791 # It's probably not useful to include this yourself.
793 # Before venturing further into these twisty passages, it is
794 # wise to read the perldebguts man page or risk the ire of dragons.
796 # (It should be noted that perldebguts will tell you a lot about
797 # the underlying mechanics of how the debugger interfaces into the
798 # Perl interpreter, but not a lot about the debugger itself. The new
799 # comments in this code try to address this problem.)
801 # Note that no subroutine call is possible until &DB::sub is defined
802 # (for subroutines defined outside of the package DB). In fact the same is
803 # true if $deep is not defined.
805 # Enhanced by ilya@math.ohio-state.edu (Ilya Zakharevich)
807 # modified Perl debugger, to be run from Emacs in perldb-mode
808 # Ray Lischner (uunet!mntgfx!lisch) as of 5 Nov 1990
809 # Johan Vromans -- upgrade to 4.0 pl 10
810 # Ilya Zakharevich -- patches after 5.001 (and some before ;-)
811 ########################################################################
813 =head1 DEBUGGER INITIALIZATION
815 The debugger starts up in phases.
819 First, it initializes the environment it wants to run in: turning off
820 warnings during its own compilation, defining variables which it will need
821 to avoid warnings later, setting itself up to not exit when the program
822 terminates, and defaulting to printing return values for the C<r> command.
826 # Needed for the statement after exec():
828 # This BEGIN block is simply used to switch off warnings during debugger
829 # compilation. Probably it would be better practice to fix the warnings,
830 # but this is how it's done at the moment.
835 } # Switch compilation warnings off until another BEGIN.
837 local ($^W) = 0; # Switch run-time warnings off during init.
839 =head2 THREADS SUPPORT
841 If we are running under a threaded Perl, we require threads and threads::shared
842 if the environment variable C<PERL5DB_THREADED> is set, to enable proper
843 threaded debugger control. C<-dt> can also be used to set this.
845 Each new thread will be announced and the debugger prompt will always inform
846 you of each new thread created. It will also indicate the thread id in which
847 we are currently running within the prompt like this:
851 Where C<[tid]> is an integer thread id and C<$i> is the familiar debugger
852 command prompt. The prompt will show: C<[0]> when running under threads, but
853 not actually in a thread. C<[tid]> is consistent with C<gdb> usage.
855 While running under threads, when you set or delete a breakpoint (etc.), this
856 will apply to all threads, not just the currently running one. When you are
857 in a currently executing thread, you will stay there until it completes. With
858 the current implementation it is not currently possible to hop from one thread
861 The C<e> and C<E> commands are currently fairly minimal - see
862 S<C<h e>> and S<C<h E>>.
864 Note that threading support was built into the debugger as of Perl version
865 C<5.8.6> and debugger version C<1.2.8>.
870 # ensure we can share our non-threaded variables or no-op
871 if ($ENV{PERL5DB_THREADED}) {
873 require threads::shared;
874 import threads::shared qw(share);
878 print "Threads support enabled\n";
880 *lock = sub :prototype(*) {};
881 *share = sub :prototype(\[$@%]) {};
885 # These variables control the execution of 'dumpvar.pl'.
900 # used to control die() reporting in diesignal()
903 use vars qw($CarpLevel);
906 # without threads, $filename is not defined until DB::DB is called
907 share($main::{'_<'.$filename}) if defined $filename;
909 # Command-line + PERLLIB:
910 # Save the contents of @INC before they are modified elsewhere.
913 # This was an attempt to clear out the previous values of various
914 # trapped errors. Apparently it didn't help. XXX More info needed!
915 # $prevwarn = $prevdie = $prevbus = $prevsegv = ''; # Does not help?!
917 # We set these variables to safe values. We don't want to blindly turn
918 # off warnings, because other packages may still want them.
919 $trace = $signal = $single = 0; # Uninitialized warning suppression
920 # (local $^W cannot help - other packages!).
922 # Default to not exiting when program finishes; print the return
923 # value when the 'r' command is used to return from a subroutine.
924 $inhibit_exit = $option{PrintRet} = 1;
926 use vars qw($trace_to_depth);
928 # Default to 1E9 so it won't be limited to a certain recursion depth.
929 $trace_to_depth = 1E9;
931 =head1 OPTION PROCESSING
933 The debugger's options are actually spread out over the debugger itself and
934 C<dumpvar.pl>; some of these are variables to be set, while others are
935 subs to be called with a value. To try to make this a little easier to
936 manage, the debugger uses a few data structures to define what options
937 are legal and how they are to be processed.
939 First, the C<@options> array defines the I<names> of all the options that
945 CommandSet HistFile HistSize
947 hashDepth arrayDepth dumpDepth
948 DumpDBFiles DumpPackages DumpReused
949 compactDump veryCompact quote
950 HighBit undefPrint globPrint
951 PrintRet UsageOnly frame
953 ReadLine NonStop LineInfo
954 maxTraceLen recallCommand ShellBang
955 pager tkRunning ornaments
956 signalLevel warnLevel dieLevel
957 inhibit_exit ImmediateStop bareStringify
958 CreateTTY RemotePort windowSize
962 @RememberOnROptions = qw(DollarCaretP);
966 Second, C<optionVars> lists the variables that each option uses to save its
971 use vars qw(%optionVars);
974 hashDepth => \$dumpvar::hashDepth,
975 arrayDepth => \$dumpvar::arrayDepth,
976 CommandSet => \$CommandSet,
977 DumpDBFiles => \$dumpvar::dumpDBFiles,
978 DumpPackages => \$dumpvar::dumpPackages,
979 DumpReused => \$dumpvar::dumpReused,
980 HighBit => \$dumpvar::quoteHighBit,
981 undefPrint => \$dumpvar::printUndef,
982 globPrint => \$dumpvar::globPrint,
983 UsageOnly => \$dumpvar::usageOnly,
984 CreateTTY => \$CreateTTY,
985 bareStringify => \$dumpvar::bareStringify,
987 AutoTrace => \$trace,
988 inhibit_exit => \$inhibit_exit,
989 maxTraceLen => \$maxtrace,
990 ImmediateStop => \$ImmediateStop,
991 RemotePort => \$remoteport,
992 windowSize => \$window,
993 HistFile => \$histfile,
994 HistSize => \$histsize,
995 HistItemMinLength => \$histitemminlength
1000 Third, C<%optionAction> defines the subroutine to be called to process each
1005 use vars qw(%optionAction);
1008 compactDump => \&dumpvar::compactDump,
1009 veryCompact => \&dumpvar::veryCompact,
1010 quote => \&dumpvar::quote,
1013 ReadLine => \&ReadLine,
1014 NonStop => \&NonStop,
1015 LineInfo => \&LineInfo,
1016 recallCommand => \&recallCommand,
1017 ShellBang => \&shellBang,
1019 signalLevel => \&signalLevel,
1020 warnLevel => \&warnLevel,
1021 dieLevel => \&dieLevel,
1022 tkRunning => \&tkRunning,
1023 ornaments => \&ornaments,
1024 RemotePort => \&RemotePort,
1025 DollarCaretP => \&DollarCaretP,
1030 Last, the C<%optionRequire> notes modules that must be C<require>d if an
1035 # Note that this list is not complete: several options not listed here
1036 # actually require that dumpvar.pl be loaded for them to work, but are
1037 # not in the table. A subsequent patch will correct this problem; for
1038 # the moment, we're just recommenting, and we are NOT going to change
1040 use vars qw(%optionRequire);
1043 compactDump => 'dumpvar.pl',
1044 veryCompact => 'dumpvar.pl',
1045 quote => 'dumpvar.pl',
1050 There are a number of initialization-related variables which can be set
1051 by putting code to set them in a BEGIN block in the C<PERL5DB> environment
1052 variable. These are:
1056 =item C<$rl> - readline control XXX needs more explanation
1058 =item C<$warnLevel> - whether or not debugger takes over warning handling
1060 =item C<$dieLevel> - whether or not debugger takes over die handling
1062 =item C<$signalLevel> - whether or not debugger takes over signal handling
1064 =item C<$pre> - preprompt actions (array reference)
1066 =item C<$post> - postprompt actions (array reference)
1070 =item C<$CreateTTY> - whether or not to create a new TTY for this debugger
1072 =item C<$CommandSet> - which command set to use (defaults to new, documented set)
1078 # These guys may be defined in $ENV{PERL5DB} :
1079 $rl = 1 unless defined $rl;
1080 $warnLevel = 1 unless defined $warnLevel;
1081 $dieLevel = 1 unless defined $dieLevel;
1082 $signalLevel = 1 unless defined $signalLevel;
1083 $pre = [] unless defined $pre;
1084 $post = [] unless defined $post;
1085 $pretype = [] unless defined $pretype;
1086 $CreateTTY = 3 unless defined $CreateTTY;
1087 $CommandSet = '580' unless defined $CommandSet;
1092 share($signalLevel);
1101 The default C<die>, C<warn>, and C<signal> handlers are set up.
1105 warnLevel($warnLevel);
1106 dieLevel($dieLevel);
1107 signalLevel($signalLevel);
1111 The pager to be used is needed next. We try to get it from the
1112 environment first. If it's not defined there, we try to find it in
1113 the Perl C<Config.pm>. If it's not there, we default to C<more>. We
1114 then call the C<pager()> function to save the pager name.
1118 # This routine makes sure $pager is set up so that '|' can use it.
1121 # If PAGER is defined in the environment, use it.
1125 # If not, see if Config.pm defines it.
1126 : eval { require Config }
1127 && defined $Config::Config{pager}
1128 ? $Config::Config{pager}
1130 # If not, fall back to 'more'.
1133 unless defined $pager;
1137 We set up the command to be used to access the man pages, the command
1138 recall character (C<!> unless otherwise defined) and the shell escape
1139 character (C<!> unless otherwise defined). Yes, these do conflict, and
1140 neither works in the debugger at the moment.
1146 # Set up defaults for command recall and shell escape (note:
1147 # these currently don't work in linemode debugging).
1148 recallCommand("!") unless defined $prc;
1149 shellBang("!") unless defined $psh;
1153 We then set up the gigantic string containing the debugger help.
1154 We also set the limit on the number of arguments we'll display during a
1161 # If we didn't get a default for the length of eval/stack trace args,
1163 $maxtrace = 400 unless defined $maxtrace;
1165 =head2 SETTING UP THE DEBUGGER GREETING
1167 The debugger I<greeting> helps to inform the user how many debuggers are
1168 running, and whether the current debugger is the primary or a child.
1170 If we are the primary, we just hang onto our pid so we'll have it when
1171 or if we start a child debugger. If we are a child, we'll set things up
1172 so we'll have a unique greeting and so the parent will give us our own
1175 We save the current contents of the C<PERLDB_PIDS> environment variable
1176 because we mess around with it. We'll also need to hang onto it because
1177 we'll need it if we restart.
1179 Child debuggers make a label out of the current PID structure recorded in
1180 PERLDB_PIDS plus the new PID. They also mark themselves as not having a TTY
1181 yet so the parent will give them one later via C<resetterm()>.
1185 # Save the current contents of the environment; we're about to
1186 # much with it. We'll need this if we have to restart.
1187 use vars qw($ini_pids);
1188 $ini_pids = $ENV{PERLDB_PIDS};
1190 use vars qw ($pids $term_pid);
1192 if ( defined $ENV{PERLDB_PIDS} ) {
1194 # We're a child. Make us a label out of the current PID structure
1195 # recorded in PERLDB_PIDS plus our (new) PID. Mark us as not having
1196 # a term yet so the parent will give us one later via resetterm().
1198 my $env_pids = $ENV{PERLDB_PIDS};
1199 $pids = "[$env_pids]";
1201 # Unless we are on OpenVMS, all programs under the DCL shell run under
1204 if (($^O eq 'VMS') && ($env_pids =~ /\b$$\b/)) {
1208 $ENV{PERLDB_PIDS} .= "->$$";
1212 } ## end if (defined $ENV{PERLDB_PIDS...
1215 # We're the parent PID. Initialize PERLDB_PID in case we end up with a
1216 # child debugger, and mark us as the parent, so we'll know to set up
1217 # more TTY's is we have to.
1218 $ENV{PERLDB_PIDS} = "$$";
1223 use vars qw($pidprompt);
1226 # Sets up $emacs as a synonym for $client_editor.
1227 our ($client_editor);
1228 *emacs = $client_editor if $client_editor; # May be used in afterinit()...
1230 =head2 READING THE RC FILE
1232 The debugger will read a file of initialization options if supplied. If
1233 running interactively, this is C<.perldb>; if not, it's C<perldb.ini>.
1237 # As noted, this test really doesn't check accurately that the debugger
1238 # is running at a terminal or not.
1240 use vars qw($rcfile);
1242 my $dev_tty = (($^O eq 'VMS') ? 'TT:' : '/dev/tty');
1243 # this is the wrong metric!
1244 $rcfile = ((-e $dev_tty) ? ".perldb" : "perldb.ini");
1249 The debugger does a safety test of the file to be read. It must be owned
1250 either by the current user or root, and must only be writable by the owner.
1254 # This wraps a safety test around "do" to read and evaluate the init file.
1256 # This isn't really safe, because there's a race
1257 # between checking and opening. The solution is to
1258 # open and fstat the handle, but then you have to read and
1259 # eval the contents. But then the silly thing gets
1260 # your lexical scope, which is unfortunate at best.
1264 # Just exactly what part of the word "CORE::" don't you understand?
1265 local $SIG{__WARN__};
1266 local $SIG{__DIE__};
1268 unless ( is_safe_file($file) ) {
1269 CORE::warn <<EO_GRIPE;
1270 perldb: Must not source insecure rcfile $file.
1271 You or the superuser must be the owner, and it must not
1272 be writable by anyone but its owner.
1275 } ## end unless (is_safe_file($file...
1278 CORE::warn("perldb: couldn't parse $file: $@") if $@;
1279 } ## end sub safe_do
1281 # This is the safety test itself.
1283 # Verifies that owner is either real user or superuser and that no
1284 # one but owner may write to it. This function is of limited use
1285 # when called on a path instead of upon a handle, because there are
1286 # no guarantees that filename (by dirent) whose file (by ino) is
1287 # eventually accessed is the same as the one tested.
1288 # Assumes that the file's existence is not in doubt.
1291 stat($path) || return; # mysteriously vaporized
1292 my ( $dev, $ino, $mode, $nlink, $uid, $gid ) = stat(_);
1294 return 0 if $uid != 0 && $uid != $<;
1295 return 0 if $mode & 022;
1297 } ## end sub is_safe_file
1299 # If the rcfile (whichever one we decided was the right one to read)
1300 # exists, we safely do it.
1302 safe_do("./$rcfile");
1305 # If there isn't one here, try the user's home directory.
1306 elsif ( defined $ENV{HOME} && -f "$ENV{HOME}/$rcfile" ) {
1307 safe_do("$ENV{HOME}/$rcfile");
1310 # Else try the login directory.
1311 elsif ( defined $ENV{LOGDIR} && -f "$ENV{LOGDIR}/$rcfile" ) {
1312 safe_do("$ENV{LOGDIR}/$rcfile");
1315 # If the PERLDB_OPTS variable has options in it, parse those out next.
1316 if ( defined $ENV{PERLDB_OPTS} ) {
1317 parse_options( $ENV{PERLDB_OPTS} );
1322 The last thing we do during initialization is determine which subroutine is
1323 to be used to obtain a new terminal when a new debugger is started. Right now,
1324 the debugger only handles TCP sockets, X11, OS/2, amd Mac OS X
1329 # Set up the get_fork_TTY subroutine to be aliased to the proper routine.
1330 # Works if you're running an xterm or xterm-like window, or you're on
1331 # OS/2, or on Mac OS X. This may need some expansion.
1333 if (not defined &get_fork_TTY) # only if no routine exists
1335 if ( defined $remoteport ) {
1336 # Expect an inetd-like server
1337 *get_fork_TTY = \&socket_get_fork_TTY; # to listen to us
1339 elsif (defined $ENV{TERM} # If we know what kind
1340 # of terminal this is,
1341 and $ENV{TERM} eq 'xterm' # and it's an xterm,
1342 and defined $ENV{DISPLAY} # and what display it's on,
1345 *get_fork_TTY = \&xterm_get_fork_TTY; # use the xterm version
1347 elsif ( $ENV{TMUX} ) {
1348 *get_fork_TTY = \&tmux_get_fork_TTY;
1350 elsif ( $^O eq 'os2' ) { # If this is OS/2,
1351 *get_fork_TTY = \&os2_get_fork_TTY; # use the OS/2 version
1353 elsif ( $^O eq 'darwin' # If this is Mac OS X
1354 and defined $ENV{TERM_PROGRAM} # and we're running inside
1355 and $ENV{TERM_PROGRAM}
1356 eq 'Apple_Terminal' # Terminal.app
1359 *get_fork_TTY = \&macosx_get_fork_TTY; # use the Mac OS X version
1361 } ## end if (not defined &get_fork_TTY...
1363 # untaint $^O, which may have been tainted by the last statement.
1364 # see bug [perl #24674]
1368 # Here begin the unreadable code. It needs fixing.
1370 =head2 RESTART PROCESSING
1372 This section handles the restart command. When the C<R> command is invoked, it
1373 tries to capture all of the state it can into environment variables, and
1374 then sets C<PERLDB_RESTART>. When we start executing again, we check to see
1375 if C<PERLDB_RESTART> is there; if so, we reload all the information that
1376 the R command stuffed into the environment variables.
1378 PERLDB_RESTART - flag only, contains no restart data itself.
1379 PERLDB_HIST - command history, if it's available
1380 PERLDB_ON_LOAD - breakpoints set by the rc file
1381 PERLDB_POSTPONE - subs that have been loaded/not executed,
1383 PERLDB_VISITED - files that had breakpoints
1384 PERLDB_FILE_... - breakpoints for a file
1385 PERLDB_OPT - active options
1386 PERLDB_INC - the original @INC
1387 PERLDB_PRETYPE - preprompt debugger actions
1388 PERLDB_PRE - preprompt Perl code
1389 PERLDB_POST - post-prompt Perl code
1390 PERLDB_TYPEAHEAD - typeahead captured by readline()
1392 We chug through all these variables and plug the values saved in them
1393 back into the appropriate spots in the debugger.
1397 use vars qw(%postponed_file @typeahead);
1399 our (@hist, @truehist);
1401 sub _restore_shared_globals_after_restart
1403 @hist = get_list('PERLDB_HIST');
1404 %break_on_load = get_list("PERLDB_ON_LOAD");
1405 %postponed = get_list("PERLDB_POSTPONE");
1409 share(%break_on_load);
1413 sub _restore_breakpoints_and_actions {
1415 my @had_breakpoints = get_list("PERLDB_VISITED");
1417 for my $file_idx ( 0 .. $#had_breakpoints ) {
1418 my $filename = $had_breakpoints[$file_idx];
1419 my %pf = get_list("PERLDB_FILE_$file_idx");
1420 $postponed_file{ $filename } = \%pf if %pf;
1421 my @lines = sort {$a <=> $b} keys(%pf);
1422 my @enabled_statuses = get_list("PERLDB_FILE_ENABLED_$file_idx");
1423 for my $line_idx (0 .. $#lines) {
1424 _set_breakpoint_enabled_status(
1427 ($enabled_statuses[$line_idx] ? 1 : ''),
1435 sub _restore_options_after_restart
1437 my %options_map = get_list("PERLDB_OPT");
1439 while ( my ( $opt, $val ) = each %options_map ) {
1440 $val =~ s/[\\\']/\\$1/g;
1441 parse_options("$opt'$val'");
1447 sub _restore_globals_after_restart
1449 # restore original @INC
1450 @INC = get_list("PERLDB_INC");
1453 # return pre/postprompt actions and typeahead buffer
1454 $pretype = [ get_list("PERLDB_PRETYPE") ];
1455 $pre = [ get_list("PERLDB_PRE") ];
1456 $post = [ get_list("PERLDB_POST") ];
1457 @typeahead = get_list( "PERLDB_TYPEAHEAD", @typeahead );
1463 if ( exists $ENV{PERLDB_RESTART} ) {
1465 # We're restarting, so we don't need the flag that says to restart anymore.
1466 delete $ENV{PERLDB_RESTART};
1469 _restore_shared_globals_after_restart();
1471 _restore_breakpoints_and_actions();
1474 _restore_options_after_restart();
1476 _restore_globals_after_restart();
1477 } ## end if (exists $ENV{PERLDB_RESTART...
1479 =head2 SETTING UP THE TERMINAL
1481 Now, we'll decide how the debugger is going to interact with the user.
1482 If there's no TTY, we set the debugger to run non-stop; there's not going
1483 to be anyone there to enter commands.
1487 use vars qw($notty $console $tty $LINEINFO);
1488 use vars qw($lineinfo $doccmd);
1492 # Local autoflush to avoid rt#116769,
1493 # as calling IO::File methods causes an unresolvable loop
1494 # that results in debugger failure.
1496 my $o = select($_[0]);
1508 If there is a TTY, we have to determine who it belongs to before we can
1509 proceed. If this is a client editor or graphical debugger (denoted by
1510 the first command-line switch being '-emacs'), we shift this off and
1511 set C<$rl> to 0 (XXX ostensibly to do straight reads).
1517 # Is Perl being run from a client editor or graphical debugger?
1518 # If so, don't use readline, and set $client_editor = 1.
1519 if ($client_editor = ( @main::ARGV && ( $main::ARGV[0] eq '-emacs' ) )) {
1524 #require Term::ReadLine;
1528 We then determine what the console should be on various systems:
1532 =item * Cygwin - We use C<stdin> instead of a separate device.
1536 if ( $^O eq 'cygwin' ) {
1538 # /dev/tty is binary. use stdin for textmode
1542 =item * Windows - use C<con>.
1546 elsif ( $^O eq 'MSWin32' and -e "con" ) {
1550 =item * AmigaOS - use C<CONSOLE:>.
1554 elsif ( $^O eq 'amigaos' ) {
1555 $console = "CONSOLE:";
1558 =item * VMS - use C<sys$command>.
1562 elsif ($^O eq 'VMS') {
1563 $console = 'sys$command';
1566 # Keep this penultimate, on the grounds that it satisfies a wide variety of
1567 # Unix-like systems that would otherwise need to be identified individually.
1569 =item * Unix - use F</dev/tty>.
1573 elsif ( -e "/dev/tty" ) {
1574 $console = "/dev/tty";
1580 _db_warn("Can't figure out your console, using stdin");
1588 Several other systems don't use a specific console. We S<C<undef $console>>
1589 for those (Windows using a client editor/graphical debugger, OS/2
1590 with a client editor).
1594 if ( ( $^O eq 'MSWin32' ) and ( $client_editor or defined $ENV{EMACS} ) ) {
1596 # /dev/tty is binary. use stdin for textmode
1600 # In OS/2, we need to use STDIN to get textmode too, even though
1601 # it pretty much looks like Unix otherwise.
1602 if ( defined $ENV{OS2_SHELL} and ( $client_editor or $ENV{WINDOWID} ) )
1609 If there is a TTY hanging around from a parent, we use that as the console.
1613 $console = $tty if defined $tty;
1615 =head2 SOCKET HANDLING
1617 The debugger is capable of opening a socket and carrying out a debugging
1618 session over the socket.
1620 If C<RemotePort> was defined in the options, the debugger assumes that it
1621 should try to start a debugging session on that port. It builds the socket
1622 and then tries to connect the input and output filehandles to it.
1626 # Handle socket stuff.
1628 if ( defined $remoteport ) {
1630 # If RemotePort was defined in the options, connect input and output
1632 $IN = $OUT = connect_remoteport();
1633 } ## end if (defined $remoteport)
1637 If no C<RemotePort> was defined, and we want to create a TTY on startup,
1638 this is probably a situation where multiple debuggers are running (for example,
1639 a backticked command that starts up another debugger). We create a new IN and
1640 OUT filehandle, and do the necessary mojo to create a new TTY if we know how
1648 # Two debuggers running (probably a system or a backtick that invokes
1649 # the debugger itself under the running one). create a new IN and OUT
1650 # filehandle, and do the necessary mojo to create a new tty if we
1651 # know how, and we can.
1652 create_IN_OUT(4) if $CreateTTY & 4;
1655 # If we have a console, check to see if there are separate ins and
1656 # outs to open. (They are assumed identical if not.)
1658 my ( $i, $o ) = split /,/, $console;
1659 $o = $i unless defined $o;
1661 # read/write on in, or just read, or read on STDIN.
1662 open( IN, '+<', $i )
1663 || open( IN, '<', $i )
1664 || open( IN, "<&STDIN" );
1666 # read/write/create/clobber out, or write/create/clobber out,
1667 # or merge with STDERR, or merge with STDOUT.
1668 open( OUT, '+>', $o )
1669 || open( OUT, '>', $o )
1670 || open( OUT, ">&STDERR" )
1671 || open( OUT, ">&STDOUT" ); # so we don't dongle stdout
1673 } ## end if ($console)
1674 elsif ( not defined $console ) {
1676 # No console. Open STDIN.
1677 open( IN, "<&STDIN" );
1679 # merge with STDERR, or with STDOUT.
1680 open( OUT, ">&STDERR" )
1681 || open( OUT, ">&STDOUT" ); # so we don't dongle stdout
1682 $console = 'STDIN/OUT';
1683 } ## end elsif (not defined $console)
1685 # Keep copies of the filehandles so that when the pager runs, it
1686 # can close standard input without clobbering ours.
1687 if ($console or (not defined($console))) {
1691 } ## end elsif (from if(defined $remoteport))
1693 # Unbuffer DB::OUT. We need to see responses right away.
1696 # Line info goes to debugger output unless pointed elsewhere.
1697 # Pointing elsewhere makes it possible for client editors to
1698 # keep track of file and position. We have both a filehandle
1699 # and a I/O description to keep track of.
1700 $LINEINFO = $OUT unless defined $LINEINFO;
1701 $lineinfo = $console unless defined $lineinfo;
1702 # share($LINEINFO); # <- unable to share globs
1707 To finish initialization, we show the debugger greeting,
1708 and then call the C<afterinit()> subroutine if there is one.
1712 # Show the debugger greeting.
1713 $header =~ s/.Header: ([^,]+),v(\s+\S+\s+\S+).*$/$1$2/;
1714 unless ($runnonstop) {
1717 if ( $term_pid eq '-1' ) {
1718 print $OUT "\nDaughter DB session started...\n";
1721 print $OUT "\nLoading DB routines from $header\n";
1724 $client_editor ? "enabled" : "available", ".\n"
1727 "\nEnter h or 'h h' for help, or '$doccmd perldebug' for more help.\n\n";
1728 } ## end else [ if ($term_pid eq '-1')
1729 } ## end unless ($runnonstop)
1730 } ## end else [ if ($notty)
1732 # XXX This looks like a bug to me.
1733 # Why copy to @ARGS and then futz with @args?
1736 # Make sure backslashes before single quotes are stripped out, and
1737 # keep args unless they are numeric (XXX why?)
1738 # s/\'/\\\'/g; # removed while not justified understandably
1739 # s/(.*)/'$1'/ unless /^-?[\d.]+$/; # ditto
1742 # If there was an afterinit() sub defined, call it. It will get
1743 # executed in our scope, so it can fiddle with debugger globals.
1744 if ( defined &afterinit ) { # May be defined in $rcfile
1748 # Inform us about "Stack dump during die enabled ..." in dieLevel().
1749 use vars qw($I_m_init);
1753 ############################################################ Subroutines
1759 This gigantic subroutine is the heart of the debugger. Called before every
1760 statement, its job is to determine if a breakpoint has been reached, and
1761 stop if so; read commands from the user, parse them, and execute
1762 them, and then send execution off to the next statement.
1764 Note that the order in which the commands are processed is very important;
1765 some commands earlier in the loop will actually alter the C<$cmd> variable
1766 to create other commands to be executed later. This is all highly I<optimized>
1767 but can be confusing. Check the comments for each C<$cmd ... && do {}> to
1768 see what's happening in any given command.
1772 # $cmd cannot be an our() variable unfortunately (possible perl bug?).
1802 sub _DB__determine_if_we_should_break
1804 # if we have something here, see if we should break.
1805 # $stop is lexical and local to this block - $action on the other hand
1810 && _is_breakpoint_enabled($filename, $line)
1811 && (( $stop, $action ) = split( /\0/, $dbline{$line} ) ) )
1814 # Stop if the stop criterion says to just stop.
1815 if ( $stop eq '1' ) {
1819 # It's a conditional stop; eval it in the user's context and
1820 # see if we should stop. If so, remove the one-time sigil.
1822 $evalarg = "\$DB::signal |= 1 if do {$stop}";
1823 # The &-call is here to ascertain the mutability of @_.
1825 # If the breakpoint is temporary, then delete its enabled status.
1826 if ($dbline{$line} =~ s/;9($|\0)/$1/) {
1827 _cancel_breakpoint_temp_enabled_status($filename, $line);
1830 } ## end if ($dbline{$line} && ...
1833 sub _DB__is_finished {
1834 if ($finished and $level <= 1) {
1843 sub _DB__read_next_cmd
1847 # We have a terminal, or can get one ...
1852 # ... and it belongs to this PID or we get one for this PID ...
1853 if ($term_pid != $$) {
1857 # ... and we got a line of command input ...
1858 $cmd = DB::readline(
1859 "$pidprompt $tid DB"
1862 . ( '>' x $level ) . " "
1865 return defined($cmd);
1868 sub _DB__trim_command_and_return_first_component {
1871 $cmd =~ s/\A\s+//s; # trim annoying leading whitespace
1872 $cmd =~ s/\s+\z//s; # trim annoying trailing whitespace
1874 # A single-character debugger command can be immediately followed by its
1875 # argument if they aren't both alphanumeric; otherwise require space
1876 # between commands and arguments:
1877 my ($verb, $args) = $cmd =~ m{\A([^\.-]\b|\S*)\s*(.*)}s;
1879 $obj->cmd_verb($verb);
1880 $obj->cmd_args($args);
1885 sub _DB__handle_f_command {
1888 if ($file = $obj->cmd_args) {
1889 # help for no arguments (old-style was return from sub).
1892 "The old f command is now the r command.\n"; # hint
1893 print $OUT "The new f command switches filenames.\n";
1895 } ## end if (!$file)
1897 # if not in magic file list, try a close match.
1898 if ( !defined $main::{ '_<' . $file } ) {
1899 if ( ($try) = grep( m#^_<.*$file#, keys %main:: ) ) {
1901 $try = substr( $try, 2 );
1902 print $OUT "Choosing $try matching '$file':\n";
1905 } ## end if (($try) = grep(m#^_<.*$file#...
1906 } ## end if (!defined $main::{ ...
1908 # If not successfully switched now, we failed.
1909 if ( !defined $main::{ '_<' . $file } ) {
1910 print $OUT "No file matching '$file' is loaded.\n";
1914 # We switched, so switch the debugger internals around.
1915 elsif ( $file ne $filename ) {
1916 *dbline = $main::{ '_<' . $file };
1921 } ## end elsif ($file ne $filename)
1923 # We didn't switch; say we didn't.
1925 print $OUT "Already in $file.\n";
1933 sub _DB__handle_dot_command {
1937 if ($obj->_is_full('.')) {
1938 $incr = -1; # stay at current line
1940 # Reset everything to the old location.
1942 $filename = $filename_ini;
1943 *dbline = $main::{ '_<' . $filename };
1947 print_lineinfo($obj->position());
1954 sub _DB__handle_y_command {
1957 if (my ($match_level, $match_vars)
1958 = $obj->cmd_args =~ /\A(?:(\d*)\s*(.*))?\z/) {
1960 # See if we've got the necessary support.
1963 pop @INC if $INC[-1] eq '.';
1964 require PadWalker; PadWalker->VERSION(0.08) }) {
1968 ? "PadWalker module not found - please install\n"
1974 # Load up dumpvar if we don't have it. If we can, that is.
1975 do 'dumpvar.pl' || die $@ unless defined &main::dumpvar;
1976 defined &main::dumpvar
1977 or print $OUT "dumpvar.pl not available.\n"
1980 # Got all the modules we need. Find them and print them.
1981 my @vars = split( ' ', $match_vars || '' );
1984 my $h = eval { PadWalker::peek_my( ( $match_level || 0 ) + 2 ) };
1986 # Oops. Can't find it.
1993 # Show the desired vars with dumplex().
1994 my $savout = select($OUT);
1996 # Have dumplex dump the lexicals.
1997 foreach my $key (sort keys %$h) {
1998 dumpvar::dumplex( $key, $h->{$key},
1999 defined $option{dumpDepth} ? $option{dumpDepth} : -1,
2007 sub _DB__handle_c_command {
2010 my $i = $obj->cmd_args;
2012 if ($i =~ m#\A[\w:]*\z#) {
2014 # Hey, show's over. The debugged program finished
2015 # executing already.
2016 next CMD if _DB__is_finished();
2018 # Capture the place to put a one-time break.
2021 # Probably not needed, since we finish an interactive
2022 # sub-session anyway...
2023 # local $filename = $filename;
2024 # local *dbline = *dbline; # XXX Would this work?!
2026 # The above question wonders if localizing the alias
2027 # to the magic array works or not. Since it's commented
2028 # out, we'll just leave that to speculation for now.
2030 # If the "subname" isn't all digits, we'll assume it
2031 # is a subroutine name, and try to find it.
2032 if ( $subname =~ /\D/ ) { # subroutine name
2033 # Qualify it to the current package unless it's
2034 # already qualified.
2035 $subname = $package . "::" . $subname
2036 unless $subname =~ /::/;
2038 # find_sub will return "file:line_number" corresponding
2039 # to where the subroutine is defined; we call find_sub,
2040 # break up the return value, and assign it in one
2042 ( $file, $i ) = ( find_sub($subname) =~ /^(.*):(.*)$/ );
2044 # Force the line number to be numeric.
2047 # If we got a line number, we found the sub.
2050 # Switch all the debugger's internals around so
2051 # we're actually working with that file.
2053 *dbline = $main::{ '_<' . $filename };
2055 # Mark that there's a breakpoint in this file.
2056 $had_breakpoints{$filename} |= 1;
2058 # Scan forward to the first executable line
2059 # after the 'sub whatever' line.
2062 while ($dbline[$_line_num] == 0 && $_line_num< $max)
2069 # We didn't find a sub by that name.
2071 print $OUT "Subroutine $subname not found.\n";
2074 } ## end if ($subname =~ /\D/)
2076 # At this point, either the subname was all digits (an
2077 # absolute line-break request) or we've scanned through
2078 # the code following the definition of the sub, looking
2079 # for an executable, which we may or may not have found.
2081 # If $i (which we set $subname from) is non-zero, we
2082 # got a request to break at some line somewhere. On
2083 # one hand, if there wasn't any real subroutine name
2084 # involved, this will be a request to break in the current
2085 # file at the specified line, so we have to check to make
2086 # sure that the line specified really is breakable.
2088 # On the other hand, if there was a subname supplied, the
2089 # preceding block has moved us to the proper file and
2090 # location within that file, and then scanned forward
2091 # looking for the next executable line. We have to make
2092 # sure that one was found.
2094 # On the gripping hand, we can't do anything unless the
2095 # current value of $i points to a valid breakable line.
2100 if ( $dbline[$i] == 0 ) {
2101 print $OUT "Line $i not breakable.\n";
2105 # Yes. Set up the one-time-break sigil.
2106 $dbline{$i} =~ s/($|\0)/;9$1/; # add one-time-only b.p.
2107 _enable_breakpoint_temp_enabled_status($filename, $i);
2110 # Turn off stack tracing from here up.
2111 for my $j (0 .. $stack_depth) {
2120 my $sub_twice = chr utf8::unicode_to_native(032);
2121 $sub_twice = $sub_twice x 2;
2123 sub _DB__handle_forward_slash_command {
2126 # The pattern as a string.
2127 use vars qw($inpat);
2129 if (($inpat) = $cmd =~ m#\A/(.*)\z#) {
2131 # Remove the final slash.
2132 $inpat =~ s:([^\\])/$:$1:;
2134 # If the pattern isn't null ...
2135 if ( $inpat ne "" ) {
2137 # Turn off warn and die processing for a bit.
2138 local $SIG{__DIE__};
2139 local $SIG{__WARN__};
2141 # Create the pattern.
2142 eval 'no strict q/vars/; $inpat =~ m' . "\a$inpat\a";
2145 # Oops. Bad pattern. No biscuit.
2146 # Print the eval error and go back for more
2152 } ## end if ($inpat ne "")
2154 # Set up to stop on wrap-around.
2157 # Don't move off the current line.
2160 my $pat = $obj->pat;
2162 # Done in eval so nothing breaks if the pattern
2163 # does something weird.
2168 # Move ahead one line.
2171 # Wrap if we pass the last line.
2172 if ($start > $max) {
2176 # Stop if we have gotten back to this line again,
2177 last if ($start == $end);
2179 # A hit! (Note, though, that we are doing
2180 # case-insensitive matching. Maybe a qr//
2181 # expression would be better, so the user could
2182 # do case-sensitive matching if desired.
2183 if ($dbline[$start] =~ m/$pat/i) {
2184 if ($client_editor) {
2185 # Handle proper escaping in the client.
2186 print {$OUT} "$sub_twice$filename:$start:0\n";
2189 # Just print the line normally.
2190 print {$OUT} "$start:\t",$dbline[$start],"\n";
2192 # And quit since we found something.
2202 # If we wrapped, there never was a match.
2203 if ( $start == $end ) {
2204 print {$OUT} "/$pat/: not found\n";
2212 sub _DB__handle_question_mark_command {
2215 # ? - backward pattern search.
2216 if (my ($inpat) = $cmd =~ m#\A\?(.*)\z#) {
2218 # Get the pattern, remove trailing question mark.
2219 $inpat =~ s:([^\\])\?$:$1:;
2221 # If we've got one ...
2222 if ( $inpat ne "" ) {
2224 # Turn off die & warn handlers.
2225 local $SIG{__DIE__};
2226 local $SIG{__WARN__};
2227 eval '$inpat =~ m' . "\a$inpat\a";
2231 # Ouch. Not good. Print the error.
2236 } ## end if ($inpat ne "")
2238 # Where we are now is where to stop after wraparound.
2241 # Don't move away from this line.
2244 my $pat = $obj->pat;
2245 # Search inside the eval to prevent pattern badness
2253 # Wrap if we pass the first line.
2255 $start = $max if ($start <= 0);
2257 # Quit if we get back where we started,
2258 last if ($start == $end);
2261 if ($dbline[$start] =~ m/$pat/i) {
2262 if ($client_editor) {
2263 # Yep, follow client editor requirements.
2264 print $OUT "$sub_twice$filename:$start:0\n";
2267 # Yep, just print normally.
2268 print $OUT "$start:\t",$dbline[$start],"\n";
2277 # Say we failed if the loop never found anything,
2278 if ( $start == $end ) {
2279 print {$OUT} "?$pat?: not found\n";
2287 sub _DB__handle_restart_and_rerun_commands {
2290 my $cmd_cmd = $obj->cmd_verb;
2291 my $cmd_params = $obj->cmd_args;
2292 # R - restart execution.
2293 # rerun - controlled restart execution.
2294 if ($cmd_cmd eq 'rerun' or $cmd_params eq '') {
2296 # Change directory to the initial current working directory on
2297 # the script startup, so if the debugged program changed the
2298 # directory, then we will still be able to find the path to the
2299 # program. (perl 5 RT #121509 ).
2300 chdir ($_initial_cwd);
2302 my @args = ($cmd_cmd eq 'R' ? restart() : rerun($cmd_params));
2304 # Close all non-system fds for a clean restart. A more
2305 # correct method would be to close all fds that were not
2306 # open when the process started, but this seems to be
2307 # hard. See "debugger 'R'estart and open database
2308 # connections" on p5p.
2310 my $max_fd = 1024; # default if POSIX can't be loaded
2311 if (eval { require POSIX }) {
2312 eval { $max_fd = POSIX::sysconf(POSIX::_SC_OPEN_MAX()) };
2315 if (defined $max_fd) {
2316 foreach ($^F+1 .. $max_fd-1) {
2317 next unless open FD_TO_CLOSE, "<&=$_";
2322 # And run Perl again. We use exec() to keep the
2323 # PID stable (and that way $ini_pids is still valid).
2324 exec(@args) or print {$OUT} "exec failed: $!\n";
2332 sub _DB__handle_run_command_in_pager_command {
2335 if ($cmd =~ m#\A\|\|?\s*[^|]#) {
2336 if ( $pager =~ /^\|/ ) {
2338 # Default pager is into a pipe. Redirect I/O.
2339 open( SAVEOUT, ">&STDOUT" )
2340 || _db_warn("Can't save STDOUT");
2341 open( STDOUT, ">&OUT" )
2342 || _db_warn("Can't redirect STDOUT");
2343 } ## end if ($pager =~ /^\|/)
2346 # Not into a pipe. STDOUT is safe.
2347 open( SAVEOUT, ">&OUT" ) || _db_warn("Can't save DB::OUT");
2350 # Fix up environment to record we have less if so.
2353 unless ( $obj->piped(scalar ( open( OUT, $pager ) ) ) ) {
2355 # Couldn't open pipe to pager.
2356 _db_warn("Can't pipe output to '$pager'");
2357 if ( $pager =~ /^\|/ ) {
2359 # Redirect I/O back again.
2360 open( OUT, ">&STDOUT" ) # XXX: lost message
2361 || _db_warn("Can't restore DB::OUT");
2362 open( STDOUT, ">&SAVEOUT" )
2363 || _db_warn("Can't restore STDOUT");
2365 } ## end if ($pager =~ /^\|/)
2368 # Redirect I/O. STDOUT already safe.
2369 open( OUT, ">&STDOUT" ) # XXX: lost message
2370 || _db_warn("Can't restore DB::OUT");
2373 } ## end unless ($piped = open(OUT,...
2375 # Set up broken-pipe handler if necessary.
2376 $SIG{PIPE} = \&DB::catch
2378 && ( "" eq $SIG{PIPE} || "DEFAULT" eq $SIG{PIPE} );
2381 # Save current filehandle, and put it back.
2382 $obj->selected(scalar( select(OUT) ));
2383 # Don't put it back if pager was a pipe.
2384 if ($cmd !~ /\A\|\|/)
2386 select($obj->selected());
2390 # Trim off the pipe symbols and run the command now.
2391 $cmd =~ s#\A\|+\s*##;
2398 sub _DB__handle_m_command {
2401 if ($cmd =~ s#\Am\s+([\w:]+)\s*\z# #) {
2406 # m expr - set up DB::eval to do the work
2407 if ($cmd =~ s#\Am\b# #) { # Rest gets done by DB::eval()
2408 $onetimeDump = 'methods'; # method output gets used there
2414 sub _DB__at_end_of_every_command {
2417 # At the end of every command:
2420 # Unhook the pipe mechanism now.
2421 if ( $pager =~ /^\|/ ) {
2423 # No error from the child.
2426 # we cannot warn here: the handle is missing --tchrist
2427 close(OUT) || print SAVEOUT "\nCan't close DB::OUT\n";
2429 # most of the $? crud was coping with broken cshisms
2430 # $? is explicitly set to 0, so this never runs.
2432 print SAVEOUT "Pager '$pager' failed: ";
2434 print SAVEOUT "shell returned -1\n";
2437 print SAVEOUT ( $? & 127 )
2438 ? " (SIG#" . ( $? & 127 ) . ")"
2439 : "", ( $? & 128 ) ? " -- core dumped" : "", "\n";
2442 print SAVEOUT "status ", ( $? >> 8 ), "\n";
2446 # Reopen filehandle for our output (if we can) and
2447 # restore STDOUT (if we can).
2448 open( OUT, ">&STDOUT" ) || _db_warn("Can't restore DB::OUT");
2449 open( STDOUT, ">&SAVEOUT" )
2450 || _db_warn("Can't restore STDOUT");
2452 # Turn off pipe exception handler if necessary.
2453 $SIG{PIPE} = "DEFAULT" if $SIG{PIPE} eq \&DB::catch;
2455 # Will stop ignoring SIGPIPE if done like nohup(1)
2456 # does SIGINT but Perl doesn't give us a choice.
2457 } ## end if ($pager =~ /^\|/)
2460 # Non-piped "pager". Just restore STDOUT.
2461 open( OUT, ">&SAVEOUT" ) || _db_warn("Can't restore DB::OUT");
2464 # Let Readline know about the new filehandles.
2465 reset_IN_OUT( \*IN, \*OUT );
2467 # Close filehandle pager was using, restore the normal one
2471 if ($obj->selected() ne "") {
2472 select($obj->selected);
2478 } ## end if ($piped)
2483 sub _DB__handle_watch_expressions
2487 if ( $DB::trace & 2 ) {
2488 for my $n (0 .. $#DB::to_watch) {
2489 $DB::evalarg = $DB::to_watch[$n];
2490 local $DB::onetimeDump; # Tell DB::eval() to not output results
2492 # Fix context DB::eval() wants to return an array, but
2493 # we need a scalar here.
2494 my ($val) = join( "', '", DB::eval(@_) );
2495 $val = ( ( defined $val ) ? "'$val'" : 'undef' );
2498 if ( $val ne $DB::old_watch[$n] ) {
2500 # Yep! Show the difference, and fake an interrupt.
2502 print {$DB::OUT} <<EOP;
2503 Watchpoint $n:\t$DB::to_watch[$n] changed:
2504 old value:\t$DB::old_watch[$n]
2507 $DB::old_watch[$n] = $val;
2508 } ## end if ($val ne $old_watch...
2509 } ## end for my $n (0 ..
2510 } ## end if ($trace & 2)
2515 =head3 C<_DB__handle_i_command> - inheritance display
2517 Display the (nested) parentage of the module or object given.
2521 sub _DB__handle_i_command {
2524 my $line = $self->cmd_args;
2526 foreach my $isa ( split( /\s+/, $line ) ) {
2528 # The &-call is here to ascertain the mutability of @_.
2536 defined( ${"$_\::VERSION"} )
2537 ? ' ' . ${"$_\::VERSION"}
2539 } @{mro::get_linear_isa(ref($isa) || $isa)}
2546 =head3 C<_cmd_l_main> - list lines (command)
2548 Most of the command is taken up with transforming all the different line
2549 specification syntaxes into 'start-stop'. After that is done, the command
2550 runs a loop over C<@dbline> for the specified range of lines. It handles
2551 the printing of each line and any markers (C<==E<gt>> for current line,
2552 C<b> for break on this line, C<a> for action on this line, C<:> for this
2555 We save the last line listed in the C<$start> global for further listing
2562 foreach my $v (@_) {
2572 foreach my $v (@_) {
2580 sub _minify_to_max {
2583 $$ref = _min($$ref, $max);
2588 sub _cmd_l_handle_var_name {
2589 my $var_name = shift;
2591 $evalarg = $var_name;
2593 my ($s) = DB::eval();
2595 # Ooops. Bad scalar.
2597 print {$OUT} "Error: $@\n";
2601 # Good scalar. If it's a reference, find what it points to.
2603 print {$OUT} "Interpreted as: $1 $s\n";
2606 # Call self recursively to really do the command.
2607 return _cmd_l_main( $s );
2610 sub _cmd_l_handle_subname {
2615 $subname =~ s/\'/::/;
2617 # Put it in this package unless it starts with ::.
2618 $subname = $package . "::" . $subname unless $subname =~ /::/;
2620 # Put it in CORE::GLOBAL if t doesn't start with :: and
2621 # it doesn't live in this package and it lives in CORE::GLOBAL.
2622 $subname = "CORE::GLOBAL::$s"
2623 if not defined &$subname
2625 and defined &{"CORE::GLOBAL::$s"};
2627 # Put leading '::' names into 'main::'.
2628 $subname = "main" . $subname if substr( $subname, 0, 2 ) eq "::";
2630 # Get name:start-stop from find_sub, and break this up at
2632 my @pieces = split( /:/, find_sub($subname) || $sub{$subname} );
2634 # Pull off start-stop.
2635 my $subrange = pop @pieces;
2637 # If the name contained colons, the split broke it up.
2638 # Put it back together.
2639 $file = join( ':', @pieces );
2641 # If we're not in that file, switch over to it.
2642 if ( $file ne $filename ) {
2643 if (! $client_editor) {
2644 print {$OUT} "Switching to file '$file'.\n";
2647 # Switch debugger's magic structures.
2648 *dbline = $main::{ '_<' . $file };
2651 } ## end if ($file ne $filename)
2653 # Subrange is 'start-stop'. If this is less than a window full,
2654 # swap it to 'start+', which will list a window from the start point.
2656 if ( eval($subrange) < -$window ) {
2657 $subrange =~ s/-.*/+/;
2660 # Call self recursively to list the range.
2661 return _cmd_l_main( $subrange );
2662 } ## end if ($subrange)
2666 print {$OUT} "Subroutine $subname not found.\n";
2672 # Compute new range to list.
2673 $incr = $window - 1;
2676 return _cmd_l_main( $start . '-' . ( $start + $incr ) );
2680 my ($new_start, $new_incr) = @_;
2682 # Don't reset start for 'l +nnn'.
2683 $start = $new_start if $new_start;
2685 # Increment for list. Use window size if not specified.
2686 # (Allows 'l +' to work.)
2687 $incr = $new_incr || ($window - 1);
2689 # Create a line range we'll understand, and recurse to do it.
2690 return _cmd_l_main( $start . '-' . ( $start + $incr ) );
2693 sub _cmd_l_calc_initial_end_and_i {
2694 my ($spec, $start_match, $end_match) = @_;
2696 # Determine end point; use end of file if not specified.
2697 my $end = ( !defined $start_match ) ? $max :
2698 ( $end_match ? $end_match : $start_match );
2700 # Go on to the end, and then stop.
2701 _minify_to_max(\$end);
2703 # Determine start line.
2704 my $i = $start_match;
2718 my ($spec, $current_line, $start_match, $end_match) = @_;
2721 _cmd_l_calc_initial_end_and_i($spec, $start_match, $end_match);
2723 # If we're running under a client editor, force it to show the lines.
2724 if ($client_editor) {
2725 print {$OUT} "$sub_twice$filename:$i:0\n";
2728 # We're doing it ourselves. We want to show the line and special
2730 # - the current line in execution
2731 # - whether a line is breakable or not
2732 # - whether a line has a break or not
2733 # - whether a line has an action or not
2736 for ( ; $i <= $end ; $i++ ) {
2738 # Check for breakpoints and actions.
2739 my ( $stop, $action );
2741 ( $stop, $action ) = split( /\0/, $dbline{$i} );
2744 # ==> if this is the current line in execution,
2745 # : if it's breakable.
2747 ( $i == $current_line and $filename eq $filename_ini )
2749 : ( $dbline[$i] + 0 ? ':' : ' ' );
2751 # Add break and action indicators.
2752 $arrow .= 'b' if $stop;
2753 $arrow .= 'a' if $action;
2756 print {$OUT} "$i$arrow\t", $dbline[$i];
2758 # Move on to the next line. Drop out on an interrupt.
2763 } ## end for (; $i <= $end ; $i++)
2765 # Line the prompt up; print a newline if the last line listed
2766 # didn't have a newline.
2767 if ($dbline[ $i - 1 ] !~ /\n\z/) {
2770 } ## end else [ if ($client_editor)
2772 # Save the point we last listed to in case another relative 'l'
2773 # command is desired. Don't let it run off the end.
2775 _minify_to_max(\$start);
2783 # If this is '-something', delete any spaces after the dash.
2784 $spec =~ s/\A-\s*\z/-/;
2786 # If the line is '$something', assume this is a scalar containing a
2788 # Set up for DB::eval() - evaluate in *user* context.
2789 if ( my ($var_name) = $spec =~ /\A(\$.*)/s ) {
2790 return _cmd_l_handle_var_name($var_name);
2792 # l name. Try to find a sub by that name.
2793 elsif ( ($subname) = $spec =~ /\A([\':A-Za-z_][\':\w]*(?:\[.*\])?)/s ) {
2794 return _cmd_l_handle_subname();
2797 elsif ( $spec !~ /\S/ ) {
2798 return _cmd_l_empty();
2800 # l [start]+number_of_lines
2801 elsif ( my ($new_start, $new_incr) = $spec =~ /\A(\d*)\+(\d*)\z/ ) {
2802 return _cmd_l_plus($new_start, $new_incr);
2804 # l start-stop or l start,stop
2805 elsif (my ($s, $e) = $spec =~ /^(?:(-?[\d\$\.]+)(?:[-,]([\d\$\.]+))?)?/ ) {
2806 return _cmd_l_range($spec, $line, $s, $e);
2810 } ## end sub _cmd_l_main
2812 sub _DB__handle_l_command {
2815 _cmd_l_main($self->cmd_args);
2822 # 'v' is the value (i.e: method name or subroutine ref).
2823 # 's' is subroutine.
2830 '-' => { t => 'm', v => '_handle_dash_command', },
2831 '.' => { t => 's', v => \&_DB__handle_dot_command, },
2832 '=' => { t => 'm', v => '_handle_equal_sign_command', },
2833 'H' => { t => 'm', v => '_handle_H_command', },
2834 'S' => { t => 'm', v => '_handle_S_command', },
2835 'T' => { t => 'm', v => '_handle_T_command', },
2836 'W' => { t => 'm', v => '_handle_W_command', },
2837 'c' => { t => 's', v => \&_DB__handle_c_command, },
2838 'f' => { t => 's', v => \&_DB__handle_f_command, },
2839 'i' => { t => 's', v => \&_DB__handle_i_command, },
2840 'l' => { t => 's', v => \&_DB__handle_l_command, },
2841 'm' => { t => 's', v => \&_DB__handle_m_command, },
2842 'n' => { t => 'm', v => '_handle_n_command', },
2843 'p' => { t => 'm', v => '_handle_p_command', },
2844 'q' => { t => 'm', v => '_handle_q_command', },
2845 'r' => { t => 'm', v => '_handle_r_command', },
2846 's' => { t => 'm', v => '_handle_s_command', },
2847 'save' => { t => 'm', v => '_handle_save_command', },
2848 'source' => { t => 'm', v => '_handle_source_command', },
2849 't' => { t => 'm', v => '_handle_t_command', },
2850 'w' => { t => 'm', v => '_handle_w_command', },
2851 'x' => { t => 'm', v => '_handle_x_command', },
2852 'y' => { t => 's', v => \&_DB__handle_y_command, },
2853 (map { $_ => { t => 'm', v => '_handle_V_command_and_X_command', }, }
2855 (map { $_ => { t => 'm', v => '_handle_enable_disable_commands', }, }
2856 qw(enable disable)),
2858 { t => 's', v => \&_DB__handle_restart_and_rerun_commands, },
2860 (map { $_ => {t => 'm', v => '_handle_cmd_wrapper_commands' }, }
2861 qw(a A b B e E h L M o O v w W)),
2867 # lock the debugger and get the thread id for the prompt
2871 my ($prefix, $after, $infix);
2877 if ($ENV{PERL5DB_THREADED}) {
2878 $tid = eval { "[".threads->tid."]" };
2884 my $obj = DB::Obj->new(
2886 position => \$position,
2889 explicit_stop => \$explicit_stop,
2891 cmd_args => \$cmd_args,
2892 cmd_verb => \$cmd_verb,
2895 selected => \$selected,
2899 $obj->_DB_on_init__initialize_globals(@_);
2901 # Preserve current values of $@, $!, $^E, $,, $/, $\, $^W.
2902 # The code being debugged may have altered them.
2905 # Since DB::DB gets called after every line, we can use caller() to
2906 # figure out where we last were executing. Sneaky, eh? This works because
2907 # caller is returning all the extra information when called from the
2909 local ( $package, $filename, $line ) = caller;
2910 $filename_ini = $filename;
2912 # set up the context for DB::eval, so it can properly execute
2913 # code on behalf of the user. We add the package in so that the
2914 # code is eval'ed in the proper package (not in the debugger!).
2915 local $usercontext = _calc_usercontext($package);
2917 # Create an alias to the active file magical array to simplify
2919 local (*dbline) = $main::{ '_<' . $filename };
2921 # Last line in the program.
2924 # The &-call is here to ascertain the mutability of @_.
2925 &_DB__determine_if_we_should_break;
2927 # Preserve the current stop-or-not, and see if any of the W
2928 # (watch expressions) has changed.
2929 my $was_signal = $signal;
2931 # If we have any watch expressions ...
2932 _DB__handle_watch_expressions($obj);
2934 =head2 C<watchfunction()>
2936 C<watchfunction()> is a function that can be defined by the user; it is a
2937 function which will be run on each entry to C<DB::DB>; it gets the
2938 current package, filename, and line as its parameters.
2940 The watchfunction can do anything it likes; it is executing in the
2941 debugger's context, so it has access to all of the debugger's internal
2942 data structures and functions.
2944 C<watchfunction()> can control the debugger's actions. Any of the following
2945 will cause the debugger to return control to the user's program after
2946 C<watchfunction()> executes:
2952 Returning a false value from the C<watchfunction()> itself.
2956 Altering C<$single> to a false value.
2960 Altering C<$signal> to a false value.
2964 Turning off the C<4> bit in C<$trace> (this also disables the
2965 check for C<watchfunction()>. This can be done with
2973 # If there's a user-defined DB::watchfunction, call it with the
2974 # current package, filename, and line. The function executes in
2976 if ( $trace & 4 ) { # User-installed watch
2978 if watchfunction( $package, $filename, $line )
2981 and not( $trace & ~4 );
2982 } ## end if ($trace & 4)
2984 # Pick up any alteration to $signal in the watchfunction, and
2985 # turn off the signal now.
2986 $was_signal = $signal;
2989 =head2 GETTING READY TO EXECUTE COMMANDS
2991 The debugger decides to take control if single-step mode is on, the
2992 C<t> command was entered, or the user generated a signal. If the program
2993 has fallen off the end, we set things up so that entering further commands
2994 won't cause trouble, and we say that the program is over.
2998 # Make sure that we always print if asked for explicitly regardless
2999 # of $trace_to_depth .
3000 $explicit_stop = ($single || $was_signal);
3002 # Check to see if we should grab control ($single true,
3003 # trace set appropriately, or we got a signal).
3004 if ( $explicit_stop || ( $trace & 1 ) ) {
3005 $obj->_DB__grab_control(@_);
3006 } ## end if ($single || ($trace...
3010 If there's an action to be executed for the line we stopped at, execute it.
3011 If there are any preprompt actions, execute those as well.
3015 # If there's an action, do it now.
3018 # The &-call is here to ascertain the mutability of @_.
3023 # Are we nested another level (e.g., did we evaluate a function
3024 # that had a breakpoint in it at the debugger prompt)?
3025 if ( $single || $was_signal ) {
3027 # Yes, go down a level.
3028 local $level = $level + 1;
3030 # Do any pre-prompt actions.
3031 foreach $evalarg (@$pre) {
3032 # The &-call is here to ascertain the mutability of @_.
3036 # Complain about too much recursion if we passed the limit.
3038 print $OUT $stack_depth . " levels deep in subroutine calls!\n";
3041 # The line we're currently on. Set $incr to -1 to stay here
3042 # until we get a command that tells us to advance.
3044 $incr = -1; # for backward motion.
3046 # Tack preprompt debugger actions ahead of any actual input.
3047 @typeahead = ( @$pretype, @typeahead );
3049 =head2 WHERE ARE WE?
3051 XXX Relocate this section?
3053 The debugger normally shows the line corresponding to the current line of
3054 execution. Sometimes, though, we want to see the next line, or to move elsewhere
3055 in the file. This is done via the C<$incr>, C<$start>, and C<$max> variables.
3057 C<$incr> controls by how many lines the I<current> line should move forward
3058 after a command is executed. If set to -1, this indicates that the I<current>
3059 line shouldn't change.
3061 C<$start> is the I<current> line. It is used for things like knowing where to
3062 move forwards or backwards from when doing an C<L> or C<-> command.
3064 C<$max> tells the debugger where the last line of the current file is. It's
3065 used to terminate loops most often.
3067 =head2 THE COMMAND LOOP
3069 Most of C<DB::DB> is actually a command parsing and dispatch loop. It comes
3076 The outer part of the loop, starting at the C<CMD> label. This loop
3077 reads a command and then executes it.
3081 The inner part of the loop, starting at the C<PIPE> label. This part
3082 is wholly contained inside the C<CMD> block and only executes a command.
3083 Used to handle commands running inside a pager.
3087 So why have two labels to restart the loop? Because sometimes, it's easier to
3088 have a command I<generate> another command and then re-execute the loop to do
3089 the new command. This is faster, but perhaps a bit more convoluted.
3093 # The big command dispatch loop. It keeps running until the
3094 # user yields up control again.
3096 # If we have a terminal for input, and we get something back
3097 # from readline(), keep on processing.
3100 while (_DB__read_next_cmd($tid))
3104 # ... try to execute the input as debugger commands.
3106 # Don't stop running.
3109 # No signal is active.
3112 # Handle continued commands (ending with \):
3113 if ($cmd =~ s/\\\z/\n/) {
3114 $cmd .= DB::readline(" cont: ");
3118 =head4 The null command
3120 A newline entered by itself means I<re-execute the last command>. We grab the
3121 command out of C<$laststep> (where it was recorded previously), and copy it
3122 back into C<$cmd> to be executed below. If there wasn't any previous command,
3123 we'll do nothing below (no command will match). If there was, we also save it
3124 in the command history and fall through to allow the command parsing to pick
3129 # Empty input means repeat the last command.
3133 chomp($cmd); # get rid of the annoying extra newline
3134 if (length($cmd) >= option_val('HistItemMinLength', 2)) {
3135 push( @hist, $cmd );
3137 push( @truehist, $cmd );
3141 # This is a restart point for commands that didn't arrive
3142 # via direct user input. It allows us to 'redo PIPE' to
3143 # re-execute command processing without reading a new command.
3145 _DB__trim_command_and_return_first_component($obj);
3147 =head3 COMMAND ALIASES
3149 The debugger can create aliases for commands (these are stored in the
3150 C<%alias> hash). Before a command is executed, the command loop looks it up
3151 in the alias hash and substitutes the contents of the alias for the command,
3152 completely replacing it.
3156 # See if there's an alias for the command, and set it up if so.
3157 if ( $alias{$cmd_verb} ) {
3159 # Squelch signal handling; we want to keep control here
3160 # if something goes loco during the alias eval.
3161 local $SIG{__DIE__};
3162 local $SIG{__WARN__};
3164 # This is a command, so we eval it in the DEBUGGER's
3165 # scope! Otherwise, we can't see the special debugger
3166 # variables, or get to the debugger's subs. (Well, we
3167 # _could_, but why make it even more complicated?)
3168 eval "\$cmd =~ $alias{$cmd_verb}";
3171 print $OUT "Couldn't evaluate '$cmd_verb' alias: $@";
3174 _DB__trim_command_and_return_first_component($obj);
3175 } ## end if ($alias{$cmd_verb})
3177 =head3 MAIN-LINE COMMANDS
3179 All of these commands work up to and after the program being debugged has
3184 Quit the debugger. This entails setting the C<$fall_off_end> flag, so we don't
3185 try to execute further, cleaning any restart-related stuff out of the
3186 environment, and executing with the last value of C<$?>.
3190 # All of these commands were remapped in perl 5.8.0;
3191 # we send them off to the secondary dispatcher (see below).
3192 $obj->_handle_special_char_cmd_wrapper_commands;
3193 _DB__trim_command_and_return_first_component($obj);
3195 if (my $cmd_rec = $cmd_lookup{$cmd_verb}) {
3196 my $type = $cmd_rec->{t};
3197 my $val = $cmd_rec->{v};
3201 elsif ($type eq 's') {
3206 =head4 C<t> - trace [n]
3208 Turn tracing on or off. Inverts the appropriate bit in C<$trace> (q.v.).
3209 If level is specified, set C<$trace_to_depth>.
3211 =head4 C<S> - list subroutines matching/not matching a pattern
3213 Walks through C<%sub>, checking to see whether or not to print the name.
3215 =head4 C<X> - list variables in current package
3217 Since the C<V> command actually processes this, just change this to the
3218 appropriate C<V> command and fall through.
3220 =head4 C<V> - list variables
3222 Uses C<dumpvar.pl> to dump out the current values for selected variables.
3224 =head4 C<x> - evaluate and print an expression
3226 Hands the expression off to C<DB::eval>, setting it up to print the value
3227 via C<dumpvar.pl> instead of just printing it directly.
3229 =head4 C<m> - print methods
3231 Just uses C<DB::methods> to determine what methods are available.
3233 =head4 C<f> - switch files
3235 Switch to a different filename.
3237 =head4 C<.> - return to last-executed line.
3239 We set C<$incr> to -1 to indicate that the debugger shouldn't move ahead,
3240 and then we look up the line in the magical C<%dbline> hash.
3242 =head4 C<-> - back one window
3244 We change C<$start> to be one window back; if we go back past the first line,
3245 we set it to be the first line. We set C<$incr> to put us back at the
3246 currently-executing line, and then put a S<C<l $start +>> (list one window from
3247 C<$start>) in C<$cmd> to be executed later.
3249 =head3 PRE-580 COMMANDS VS. NEW COMMANDS: C<a, A, b, B, h, l, L, M, o, O, P, v, w, W, E<lt>, E<lt>E<lt>, E<0x7B>, E<0x7B>E<0x7B>>
3251 In Perl 5.8.0, a realignment of the commands was done to fix up a number of
3252 problems, most notably that the default case of several commands destroying
3253 the user's work in setting watchpoints, actions, etc. We wanted, however, to
3254 retain the old commands for those who were used to using them or who preferred
3255 them. At this point, we check for the new commands and call C<cmd_wrapper> to
3256 deal with them instead of processing them in-line.
3258 =head4 C<y> - List lexicals in higher scope
3260 Uses C<PadWalker> to find the lexicals supplied as arguments in a scope
3261 above the current one and then displays them using F<dumpvar.pl>.
3263 =head3 COMMANDS NOT WORKING AFTER PROGRAM ENDS
3265 All of the commands below this point don't work after the program being
3266 debugged has ended. All of them check to see if the program has ended; this
3267 allows the commands to be relocated without worrying about a 'line of
3268 demarcation' above which commands can be entered anytime, and below which
3271 =head4 C<n> - single step, but don't trace down into subs
3273 Done by setting C<$single> to 2, which forces subs to execute straight through
3274 when entered (see C<DB::sub> in L</DEBUGGER INTERFACE VARIABLES>). We also
3275 save the C<n> command in C<$laststep>,
3277 so a null command knows what to re-execute.
3279 =head4 C<s> - single-step, entering subs
3281 Sets C<$single> to 1, which causes C<DB::sub> to continue tracing inside
3282 subs. Also saves C<s> as C<$lastcmd>.
3284 =head4 C<c> - run continuously, setting an optional breakpoint
3286 Most of the code for this command is taken up with locating the optional
3287 breakpoint, which is either a subroutine name or a line number. We set
3288 the appropriate one-time-break in C<@dbline> and then turn off single-stepping
3289 in this and all call levels above this one.
3291 =head4 C<r> - return from a subroutine
3293 For C<r> to work properly, the debugger has to stop execution again
3294 immediately after the return is executed. This is done by forcing
3295 single-stepping to be on in the call level above the current one. If
3296 we are printing return values when a C<r> is executed, set C<$doret>
3297 appropriately, and force us out of the command loop.
3299 =head4 C<T> - stack trace
3301 Just calls C<DB::print_trace>.
3303 =head4 C<w> - List window around current line.
3305 Just calls C<DB::cmd_w>.
3307 =head4 C<W> - watch-expression processing.
3309 Just calls C<DB::cmd_W>.
3311 =head4 C</> - search forward for a string in the source
3313 We take the argument and treat it as a pattern. If it turns out to be a
3314 bad one, we return the error we got from trying to C<eval> it and exit.
3315 If not, we create some code to do the search and C<eval> it so it can't
3320 _DB__handle_forward_slash_command($obj);
3322 =head4 C<?> - search backward for a string in the source
3324 Same as for C</>, except the loop runs backwards.
3328 _DB__handle_question_mark_command($obj);
3330 =head4 C<$rc> - Recall command
3332 Manages the commands in C<@hist> (which is created if C<Term::ReadLine> reports
3333 that the terminal supports history). It finds the command required, puts it
3334 into C<$cmd>, and redoes the loop to execute it.
3338 # $rc - recall command.
3339 $obj->_handle_rc_recall_command;
3341 =head4 C<$sh$sh> - C<system()> command
3343 Calls the C<_db_system()> to handle the command. This keeps the C<STDIN> and
3344 C<STDOUT> from getting messed up.
3348 $obj->_handle_sh_command;
3350 =head4 C<$rc I<pattern> $rc> - Search command history
3352 Another command to manipulate C<@hist>: this one searches it with a pattern.
3353 If a command is found, it is placed in C<$cmd> and executed via C<redo>.
3357 $obj->_handle_rc_search_history_command;
3359 =head4 C<$sh> - Invoke a shell
3361 Uses C<_db_system()> to invoke a shell.
3365 =head4 C<$sh I<command>> - Force execution of a command in a shell
3367 Like the above, but the command is passed to the shell. Again, we use
3368 C<_db_system()> to avoid problems with C<STDIN> and C<STDOUT>.
3370 =head4 C<H> - display commands in history
3372 Prints the contents of C<@hist> (if any).
3374 =head4 C<man, doc, perldoc> - look up documentation
3376 Just calls C<runman()> to print the appropriate document.
3380 $obj->_handle_doc_command;
3384 Builds a C<print EXPR> expression in the C<$cmd>; this will get executed at
3385 the bottom of the loop.
3387 =head4 C<=> - define command alias
3389 Manipulates C<%alias> to add or list command aliases.
3391 =head4 C<source> - read commands from a file.
3393 Opens a lexical filehandle and stacks it on C<@cmdfhs>; C<DB::readline> will
3396 =head4 C<enable> C<disable> - enable or disable breakpoints
3398 This enables or disables breakpoints.
3400 =head4 C<save> - send current history to a file
3402 Takes the complete history, (not the shrunken version you see with C<H>),
3403 and saves it to the given filename, so it can be replayed using C<source>.
3405 Note that all C<^(save|source)>'s are commented out with a view to minimise recursion.
3407 =head4 C<R> - restart
3409 Restart the debugger session.
3411 =head4 C<rerun> - rerun the current session
3413 Return to any given position in the B<true>-history list
3415 =head4 C<|, ||> - pipe output through the pager.
3417 For C<|>, we save C<OUT> (the debugger's output filehandle) and C<STDOUT>
3418 (the program's standard output). For C<||>, we only save C<OUT>. We open a
3419 pipe to the pager (restoring the output filehandles if this fails). If this
3420 is the C<|> command, we also set up a C<SIGPIPE> handler which will simply
3421 set C<$signal>, sending us back into the debugger.
3423 We then trim off the pipe symbols and C<redo> the command loop at the
3424 C<PIPE> label, causing us to evaluate the command in C<$cmd> without
3429 # || - run command in the pager, with output to DB::OUT.
3430 _DB__handle_run_command_in_pager_command($obj);
3432 =head3 END OF COMMAND PARSING
3434 Anything left in C<$cmd> at this point is a Perl expression that we want to
3435 evaluate. We'll always evaluate in the user's context, and fully qualify
3436 any variables we might want to address in the C<DB> package.
3442 # trace an expression
3443 $cmd =~ s/^t\s/\$DB::trace |= 1;\n/;
3445 # Make sure the flag that says "the debugger's running" is
3446 # still on, to make sure we get control again.
3447 $evalarg = "\$^D = \$^D | \$DB::db_stop;\n$cmd";
3449 # Run *our* eval that executes in the caller's context.
3450 # The &-call is here to ascertain the mutability of @_.
3453 # Turn off the one-time-dump stuff now.
3455 $onetimeDump = undef;
3456 $onetimedumpDepth = undef;
3458 elsif ( $term_pid == $$ ) {
3459 eval { # May run under miniperl, when not available...
3464 # XXX If this is the master pid, print a newline.
3467 } ## end while (($term || &setterm...
3469 =head3 POST-COMMAND PROCESSING
3471 After each command, we check to see if the command output was piped anywhere.
3472 If so, we go through the necessary code to unhook the pipe and go back to
3473 our standard filehandles for input and output.
3478 _DB__at_end_of_every_command($obj);
3481 =head3 COMMAND LOOP TERMINATION
3483 When commands have finished executing, we come here. If the user closed the
3484 input filehandle, we turn on C<$fall_off_end> to emulate a C<q> command. We
3485 evaluate any post-prompt items. We restore C<$@>, C<$!>, C<$^E>, C<$,>, C<$/>,
3486 C<$\>, and C<$^W>, and return a null list as expected by the Perl interpreter.
3487 The interpreter will then execute the next line and then return control to us
3492 # No more commands? Quit.
3493 unless (defined $cmd) {
3494 DB::Obj::_do_quit();
3497 # Evaluate post-prompt commands.
3498 foreach $evalarg (@$post) {
3499 # The &-call is here to ascertain the mutability of @_.
3502 } # if ($single || $signal)
3504 # Put the user's globals back where you found them.
3505 ( $@, $!, $^E, $,, $/, $\, $^W ) = @saved;
3509 # Because DB::Obj is used above,
3511 # my $obj = DB::Obj->new(
3513 # The following package declaration must come before that,
3514 # or else runtime errors will occur with
3516 # PERLDB_OPTS="autotrace nonstop"
3526 my $self = bless {}, $class;
3534 my ($self, $args) = @_;
3536 %{$self} = (%$self, %$args);
3543 foreach my $slot_name (qw(
3544 after explicit_stop infix pat piped position prefix selected cmd_verb
3547 my $slot = $slot_name;
3552 ${ $self->{$slot} } = shift;
3555 return ${ $self->{$slot} };
3558 *{"append_to_$slot"} = sub {
3562 return $self->$slot($self->$slot . $s);
3567 sub _DB_on_init__initialize_globals
3571 # Check for whether we should be running continuously or not.
3572 # _After_ the perl program is compiled, $single is set to 1:
3573 if ( $single and not $second_time++ ) {
3575 # Options say run non-stop. Run until we get an interrupt.
3576 if ($runnonstop) { # Disable until signal
3577 # If there's any call stack in place, turn off single
3578 # stepping into subs throughout the stack.
3579 for my $i (0 .. $stack_depth) {
3583 # And we are now no longer in single-step mode.
3586 # If we simply returned at this point, we wouldn't get
3587 # the trace info. Fall on through.
3589 } ## end if ($runnonstop)
3591 elsif ($ImmediateStop) {
3593 # We are supposed to stop here; XXX probably a break.
3594 $ImmediateStop = 0; # We've processed it; turn it off
3595 $signal = 1; # Simulate an interrupt to force
3596 # us into the command loop
3598 } ## end if ($single and not $second_time...
3600 # If we're in single-step mode, or an interrupt (real or fake)
3601 # has occurred, turn off non-stop mode.
3602 $runnonstop = 0 if $single or $signal;
3607 sub _my_print_lineinfo
3609 my ($self, $i, $incr_pos) = @_;
3612 # Print it indented if tracing is on.
3613 DB::print_lineinfo( ' ' x $stack_depth,
3614 "$i:\t$DB::dbline[$i]" . $self->after );
3617 DB::depth_print_lineinfo($self->explicit_stop, $incr_pos);
3622 return $DB::dbline[$line];
3626 my ($self, $letter) = @_;
3628 return ($DB::cmd eq $letter);
3631 sub _DB__grab_control
3635 # Yes, grab control.
3636 if ($client_editor) {
3638 # Tell the editor to update its position.
3639 $self->position("$sub_twice${DB::filename}:$line:0\n");
3640 DB::print_lineinfo($self->position());
3645 Special check: if we're in package C<DB::fake>, we've gone through the
3646 C<END> block at least once. We set up everything so that we can continue
3647 to enter commands and have a valid context to be in.
3651 elsif ( $DB::package eq 'DB::fake' ) {
3653 # Fallen off the end already.
3658 DB::print_help(<<EOP);
3659 Debugged program terminated. Use B<q> to quit or B<R> to restart,
3660 use B<o> I<inhibit_exit> to avoid stopping after program termination,
3661 S<B<h q>>, S<B<h R>> or S<B<h o>> to get additional info.
3664 $DB::package = 'main';
3665 $DB::usercontext = DB::_calc_usercontext($DB::package);
3666 } ## end elsif ($package eq 'DB::fake')
3670 If the program hasn't finished executing, we scan forward to the
3671 next executable line, print that out, build the prompt from the file and line
3672 number information, and print that.
3679 # Still somewhere in the midst of execution. Set up the
3681 $DB::sub =~ s/\'/::/; # Swap Perl 4 package separators (') to
3682 # Perl 5 ones (sorry, we don't print Klingon
3685 $self->prefix($DB::sub =~ /::/ ? "" : ($DB::package . '::'));
3686 $self->append_to_prefix( "$DB::sub(${DB::filename}:" );
3687 $self->after( $self->_curr_line =~ /\n$/ ? '' : "\n" );
3689 # Break up the prompt if it's really long.
3690 if ( length($self->prefix()) > 30 ) {
3691 $self->position($self->prefix . "$line):\n$line:\t" . $self->_curr_line . $self->after);
3693 $self->infix(":\t");
3696 $self->infix("):\t");
3698 $self->prefix . $line. $self->infix
3699 . $self->_curr_line . $self->after
3703 # Print current line info, indenting if necessary.
3704 $self->_my_print_lineinfo($line, $self->position);
3707 my $line_i = sub { return $DB::dbline[$i]; };
3709 # Scan forward, stopping at either the end or the next
3711 for ( $i = $line + 1 ; $i <= $DB::max && $line_i->() == 0 ; ++$i )
3714 # Drop out on null statements, block closers, and comments.
3715 last if $line_i->() =~ /^\s*[\;\}\#\n]/;
3717 # Drop out if the user interrupted us.
3720 # Append a newline if the line doesn't have one. Can happen
3721 # in eval'ed text, for instance.
3722 $self->after( $line_i->() =~ /\n$/ ? '' : "\n" );
3724 # Next executable line.
3725 my $incr_pos = $self->prefix . $i . $self->infix . $line_i->()
3727 $self->append_to_position($incr_pos);
3728 $self->_my_print_lineinfo($i, $incr_pos);
3729 } ## end for ($i = $line + 1 ; $i...
3730 } ## end else [ if ($client_editor)
3735 sub _handle_t_command {
3738 my $levels = $self->cmd_args();
3740 if ((!length($levels)) or ($levels !~ /\D/)) {
3743 $DB::trace_to_depth = $levels ? $stack_depth + $levels : 1E9;
3744 print {$OUT} "Trace = "
3746 ? ( $levels ? "on (to level $DB::trace_to_depth)" : "on" )
3755 sub _handle_S_command {
3758 if (my ($print_all_subs, $should_reverse, $Spatt)
3759 = $self->cmd_args =~ /\A((!)?(.+))?\z/) {
3760 # $Spatt is the pattern (if any) to use.
3762 my $Srev = defined $should_reverse;
3763 # No args - print all subs.
3764 my $Snocheck = !defined $print_all_subs;
3766 # Need to make these sane here.
3770 # Search through the debugger's magical hash of subs.
3771 # If $nocheck is true, just print the sub name.
3772 # Otherwise, check it against the pattern. We then use
3773 # the XOR trick to reverse the condition as required.
3774 foreach $subname ( sort( keys %sub ) ) {
3775 if ( $Snocheck or $Srev ^ ( $subname =~ /$Spatt/ ) ) {
3776 print $OUT $subname, "\n";
3785 sub _handle_V_command_and_X_command {
3788 $DB::cmd =~ s/^X\b/V $DB::package/;
3790 # Bare V commands get the currently-being-debugged package
3792 if ($self->_is_full('V')) {
3793 $DB::cmd = "V $DB::package";
3796 # V - show variables in package.
3797 if (my ($new_packname, $new_vars_str) =
3798 $DB::cmd =~ /\AV\b\s*(\S+)\s*(.*)/) {
3800 # Save the currently selected filehandle and
3801 # force output to debugger's filehandle (dumpvar
3802 # just does "print" for output).
3803 my $savout = select($OUT);
3805 # Grab package name and variables to dump.
3806 $packname = $new_packname;
3807 my @vars = split( ' ', $new_vars_str );
3809 # If main::dumpvar isn't here, get it.
3810 do 'dumpvar.pl' || die $@ unless defined &main::dumpvar;
3811 if ( defined &main::dumpvar ) {
3813 # We got it. Turn off subroutine entry/exit messages
3814 # for the moment, along with return values.
3818 # must detect sigpipe failures - not catching
3819 # then will cause the debugger to die.
3823 defined $option{dumpDepth}
3824 ? $option{dumpDepth}
3825 : -1, # assume -1 unless specified
3830 # The die doesn't need to include the $@, because
3831 # it will automatically get propagated for us.
3833 die unless $@ =~ /dumpvar print failed/;
3835 } ## end if (defined &main::dumpvar)
3838 # Couldn't load dumpvar.
3839 print $OUT "dumpvar.pl not available.\n";
3842 # Restore the output filehandle, and go round again.
3850 sub _handle_dash_command {
3853 if ($self->_is_full('-')) {
3855 # back up by a window; go to 1 if back too far.
3856 $start -= $incr + $window + 1;
3857 $start = 1 if $start <= 0;
3858 $incr = $window - 1;
3860 # Generate and execute a "l +" command (handled below).
3861 $DB::cmd = 'l ' . ($start) . '+';
3867 sub _n_or_s_commands_generic {
3868 my ($self, $new_val) = @_;
3870 next CMD if DB::_DB__is_finished();
3872 # Single step, but don't enter subs.
3875 # Save for empty command (repeat last).
3876 $laststep = $DB::cmd;
3881 my ($self, $letter, $new_val) = @_;
3883 if ($self->_is_full($letter)) {
3884 $self->_n_or_s_commands_generic($new_val);
3887 $self->_n_or_s_and_arg_commands_generic($letter, $new_val);
3893 sub _handle_n_command {
3896 return $self->_n_or_s('n', 2);
3899 sub _handle_s_command {
3902 return $self->_n_or_s('s', 1);
3905 sub _handle_r_command {
3908 # r - return from the current subroutine.
3909 if ($self->_is_full('r')) {
3911 # Can't do anything if the program's over.
3912 next CMD if DB::_DB__is_finished();
3914 # Turn on stack trace.
3915 $stack[$stack_depth] |= 1;
3917 # Print return value unless the stack is empty.
3918 $doret = $option{PrintRet} ? $stack_depth - 1 : -2;
3925 sub _handle_T_command {
3928 if ($self->_is_full('T')) {
3929 DB::print_trace( $OUT, 1 ); # skip DB
3936 sub _handle_w_command {
3939 DB::cmd_w( 'w', $self->cmd_args() );
3945 sub _handle_W_command {
3948 if (my $arg = $self->cmd_args) {
3949 DB::cmd_W( 'W', $arg );
3956 sub _handle_rc_recall_command {
3959 # $rc - recall command.
3960 if (my ($minus, $arg) = $DB::cmd =~ m#\A$rc+\s*(-)?(\d+)?\z#) {
3962 # No arguments, take one thing off history.
3963 pop(@hist) if length($DB::cmd) > 1;
3965 # Relative (- found)?
3966 # Y - index back from most recent (by 1 if bare minus)
3967 # N - go to that particular command slot or the last
3968 # thing if nothing following.
3971 scalar($minus ? ( $#hist - ( $arg || 1 ) ) : ( $arg || $#hist ))
3974 # Pick out the command desired.
3975 $DB::cmd = $hist[$self->cmd_verb];
3977 # Print the command to be executed and restart the loop
3978 # with that command in the buffer.
3979 print {$OUT} $DB::cmd, "\n";
3986 sub _handle_rc_search_history_command {
3989 # $rc pattern $rc - find a command in the history.
3990 if (my ($arg) = $DB::cmd =~ /\A$rc([^$rc].*)\z/) {
3992 # Create the pattern to use.
3996 # Toss off last entry if length is >1 (and it always is).
3997 pop(@hist) if length($DB::cmd) > 1;
4001 # Look backward through the history.
4003 for ( $i = $#hist ; $i ; --$i ) {
4004 # Stop if we find it.
4005 last SEARCH_HIST if $hist[$i] =~ /$pat/;
4011 print $OUT "No such command!\n\n";
4015 # Found it. Put it in the buffer, print it, and process it.
4016 $DB::cmd = $hist[$i];
4017 print $OUT $DB::cmd, "\n";
4024 sub _handle_H_command {
4027 if ($self->cmd_args =~ m#\A\*#) {
4028 @hist = @truehist = ();
4029 print $OUT "History cleansed\n";
4033 if (my ($num) = $self->cmd_args =~ /\A(?:-(\d+))?/) {
4035 # Anything other than negative numbers is ignored by
4036 # the (incorrect) pattern, so this test does nothing.
4037 $end = $num ? ( $#hist - $num ) : 0;
4039 # Set to the minimum if less than zero.
4040 $hist = 0 if $hist < 0;
4042 # Start at the end of the array.
4043 # Stay in while we're still above the ending value.
4044 # Tick back by one each time around the loop.
4047 for ( $i = $#hist ; $i > $end ; $i-- ) {
4048 print $OUT "$i: ", $hist[$i], "\n";
4057 sub _handle_doc_command {
4060 # man, perldoc, doc - show manual pages.
4062 = $DB::cmd =~ /\A(?:man|(?:perl)?doc)\b(?:\s+([^(]*))?\z/) {
4063 DB::runman($man_page);
4070 sub _handle_p_command {
4073 my $print_cmd = 'print {$DB::OUT} ';
4074 # p - print (no args): print $_.
4075 if ($self->_is_full('p')) {
4076 $DB::cmd = $print_cmd . '$_';
4079 # p - print the given expression.
4080 $DB::cmd =~ s/\Ap\b/$print_cmd /;
4086 sub _handle_equal_sign_command {
4089 if ($DB::cmd =~ s/\A=\s*//) {
4091 if ( length $DB::cmd == 0 ) {
4093 # No args, get current aliases.
4094 @keys = sort keys %alias;
4096 elsif ( my ( $k, $v ) = ( $DB::cmd =~ /^(\S+)\s+(\S.*)/ ) ) {
4098 # Creating a new alias. $k is alias name, $v is
4101 # can't use $_ or kill //g state
4102 for my $x ( $k, $v ) {
4104 # Escape "alarm" characters.
4108 # Substitute key for value, using alarm chars
4109 # as separators (which is why we escaped them in
4111 $alias{$k} = "s\a$k\a$v\a";
4113 # Turn off standard warn and die behavior.
4114 local $SIG{__DIE__};
4115 local $SIG{__WARN__};
4118 unless ( eval "sub { s\a$k\a$v\a }; 1" ) {
4120 # Nope. Bad alias. Say so and get out.
4121 print $OUT "Can't alias $k to $v: $@\n";
4126 # We'll only list the new one.
4128 } ## end elsif (my ($k, $v) = ($DB::cmd...
4130 # The argument is the alias to list.
4138 # Messy metaquoting: Trim the substitution code off.
4139 # We use control-G as the delimiter because it's not
4140 # likely to appear in the alias.
4141 if ( ( my $v = $alias{$k} ) =~ s
\as\a$k\a(.*)\a$
\a1
\a ) {
4144 print $OUT "$k\t= $1\n";
4146 elsif ( defined $alias{$k} ) {
4148 # Couldn't trim it off; just print the alias code.
4149 print $OUT "$k\t$alias{$k}\n";
4154 print "No alias for $k\n";
4156 } ## end for my $k (@keys)
4163 sub _handle_source_command {
4166 # source - read commands from a file (or pipe!) and execute.
4167 if (my $sourced_fn = $self->cmd_args) {
4168 if ( open my $fh, $sourced_fn ) {
4170 # Opened OK; stick it in the list of file handles.
4176 DB::_db_warn("Can't execute '$sourced_fn': $!\n");
4184 sub _handle_enable_disable_commands {
4187 my $which_cmd = $self->cmd_verb;
4188 my $position = $self->cmd_args;
4190 if ($position !~ /\s/) {
4191 my ($fn, $line_num);
4192 if ($position =~ m{\A\d+\z})
4194 $fn = $DB::filename;
4195 $line_num = $position;
4197 elsif (my ($new_fn, $new_line_num)
4198 = $position =~ m{\A(.*):(\d+)\z}) {
4199 ($fn, $line_num) = ($new_fn, $new_line_num);
4203 DB::_db_warn("Wrong spec for enable/disable argument.\n");
4207 if (DB::_has_breakpoint_data_ref($fn, $line_num)) {
4208 DB::_set_breakpoint_enabled_status($fn, $line_num,
4209 ($which_cmd eq 'enable' ? 1 : '')
4213 DB::_db_warn("No breakpoint set at ${fn}:${line_num}\n");
4223 sub _handle_save_command {
4226 if (my $new_fn = $self->cmd_args) {
4227 my $filename = $new_fn || '.perl5dbrc'; # default?
4228 if ( open my $fh, '>', $filename ) {
4230 # chomp to remove extraneous newlines from source'd files
4231 chomp( my @truelist =
4232 map { m/\A\s*(save|source)/ ? "#$_" : $_ }
4234 print {$fh} join( "\n", @truelist );
4235 print "commands saved in $filename\n";
4238 DB::_db_warn("Can't save debugger commands in '$new_fn': $!\n");
4246 sub _n_or_s_and_arg_commands_generic {
4247 my ($self, $letter, $new_val) = @_;
4249 # s - single-step. Remember the last command was 's'.
4250 if ($DB::cmd =~ s#\A\Q$letter\E\s#\$DB::single = $new_val;\n#) {
4251 $laststep = $letter;
4257 sub _handle_sh_command {
4260 # $sh$sh - run a shell command (if it's all ASCII).
4261 # Can't run shell commands with Unicode in the debugger, hmm.
4262 my $my_cmd = $DB::cmd;
4263 if ($my_cmd =~ m#\A$sh#gms) {
4265 if ($my_cmd =~ m#\G\z#cgms) {
4266 # Run the user's shell. If none defined, run Bourne.
4267 # We resume execution when the shell terminates.
4268 DB::_db_system( $ENV{SHELL} || "/bin/sh" );
4271 elsif ($my_cmd =~ m#\G$sh\s*(.*)#cgms) {
4276 elsif ($my_cmd =~ m#\G\s*(.*)#cgms) {
4277 DB::_db_system( $ENV{SHELL} || "/bin/sh", "-c", $1 );
4283 sub _handle_x_command {
4286 if ($DB::cmd =~ s#\Ax\b# #) { # Remainder gets done by DB::eval()
4287 $onetimeDump = 'dump'; # main::dumpvar shows the output
4289 # handle special "x 3 blah" syntax XXX propagate
4290 # doc back to special variables.
4291 if ( $DB::cmd =~ s#\A\s*(\d+)(?=\s)# #) {
4292 $onetimedumpDepth = $1;
4305 sub _handle_q_command {
4308 if ($self->_is_full('q')) {
4315 sub _handle_cmd_wrapper_commands {
4318 DB::cmd_wrapper( $self->cmd_verb, $self->cmd_args, $line );
4322 sub _handle_special_char_cmd_wrapper_commands {
4325 # All of these commands were remapped in perl 5.8.0;
4326 # we send them off to the secondary dispatcher (see below).
4327 if (my ($cmd_letter, $my_arg) = $DB::cmd =~ /\A([<>\{]{1,2})\s*(.*)/so) {
4328 DB::cmd_wrapper( $cmd_letter, $my_arg, $line );
4339 # The following code may be executed now:
4344 C<sub> is called whenever a subroutine call happens in the program being
4345 debugged. The variable C<$DB::sub> contains the name of the subroutine
4348 The core function of this subroutine is to actually call the sub in the proper
4349 context, capturing its output. This of course causes C<DB::DB> to get called
4350 again, repeating until the subroutine ends and returns control to C<DB::sub>
4351 again. Once control returns, C<DB::sub> figures out whether or not to dump the
4352 return value, and returns its captured copy of the return value as its own
4353 return value. The value then feeds back into the program being debugged as if
4354 C<DB::sub> hadn't been there at all.
4356 C<sub> does all the work of printing the subroutine entry and exit messages
4357 enabled by setting C<$frame>. It notes what sub the autoloader got called for,
4358 and also prints the return value if needed (for the C<r> command and if
4359 the 16 bit is set in C<$frame>).
4361 It also tracks the subroutine call depth by saving the current setting of
4362 C<$single> in the C<@stack> package global; if this exceeds the value in
4363 C<$deep>, C<sub> automatically turns on printing of the current depth by
4364 setting the C<4> bit in C<$single>. In any case, it keeps the current setting
4365 of stop/don't stop on entry to subs set as it currently is set.
4367 =head3 C<caller()> support
4369 If C<caller()> is called from the package C<DB>, it provides some
4370 additional data, in the following order:
4376 The package name the sub was in
4378 =item * C<$filename>
4380 The filename it was defined in
4384 The line number it was defined on
4386 =item * C<$subroutine>
4388 The subroutine name; C<(eval)> if an C<eval>().
4392 1 if it has arguments, 0 if not
4394 =item * C<$wantarray>
4396 1 if array context, 0 if scalar context
4398 =item * C<$evaltext>
4400 The C<eval>() text, if any (undefined for S<C<eval BLOCK>>)
4402 =item * C<$is_require>
4404 frame was created by a C<use> or C<require> statement
4408 pragma information; subject to change between versions
4412 pragma information; subject to change between versions
4414 =item * C<@DB::args>
4416 arguments with which the subroutine was invoked
4424 # We need to fully qualify the name ("DB::sub") to make "use strict;"
4425 # happy. -- Shlomi Fish
4427 sub _indent_print_line_info {
4428 my ($offset, $str) = @_;
4430 print_lineinfo( ' ' x ($stack_depth - $offset), $str);
4435 sub _print_frame_message {
4439 if ($frame & 4) { # Extended frame entry message
4440 _indent_print_line_info(-1, "in ");
4442 # Why -1? But it works! :-(
4443 # Because print_trace will call add 1 to it and then call
4444 # dump_trace; this results in our skipping -1+1 = 0 stack frames
4447 # Now it's 0 because we extracted a function.
4448 print_trace( $LINEINFO, 0, 1, 1, "$sub$al" );
4451 _indent_print_line_info(-1, "entering $sub$al\n" );
4459 my ( $al, $ret, @ret ) = "";
4461 # We stack the stack pointer and then increment it to protect us
4462 # from a situation that might unwind a whole bunch of call frames
4463 # at once. Localizing the stack pointer means that it will automatically
4464 # unwind the same amount when multiple stack frames are unwound.
4465 local $stack_depth = $stack_depth + 1; # Protect from non-local exits
4468 # lock ourselves under threads
4469 # While lock() permits recursive locks, there's two cases where it's bad
4470 # that we keep a hold on the lock while we call the sub:
4471 # - during cloning, Package::CLONE might be called in the context of the new
4472 # thread, which will deadlock if we hold the lock across the threads::new call
4473 # - for any function that waits any significant time
4474 # This also deadlocks if the parent thread joins(), since holding the lock
4475 # will prevent any child threads passing this point.
4476 # So release the lock for the function call.
4479 # Whether or not the autoloader was running, a scalar to put the
4480 # sub's return value in (if needed), and an array to put the sub's
4481 # return value in (if needed).
4482 if ($sub eq 'threads::new' && $ENV{PERL5DB_THREADED}) {
4483 print "creating new thread\n";
4486 # If the last ten characters are '::AUTOLOAD', note we've traced
4487 # into AUTOLOAD for $sub.
4488 if ( length($sub) > 10 && substr( $sub, -10, 10 ) eq '::AUTOLOAD' ) {
4490 $al = " for $$sub" if defined $$sub;
4494 $#stack = $stack_depth;
4496 # Save current single-step setting.
4497 $stack[-1] = $single;
4499 # Turn off all flags except single-stepping.
4502 # If we've gotten really deeply recursed, turn on the flag that will
4503 # make us stop with the 'deep recursion' message.
4504 $single |= 4 if $stack_depth == $deep;
4506 # If frame messages are on ...
4508 _print_frame_message($al);
4511 # Determine the sub's return type, and capture appropriately.
4514 # Called in array context. call sub and capture output.
4515 # DB::DB will recursively get control again if appropriate; we'll come
4516 # back here when the sub is finished.
4520 elsif ( defined wantarray ) {
4522 # Save the value if it's wanted at all.
4527 # Void return, explicitly.
4535 # Pop the single-step value back off the stack.
4536 $single |= $stack[ $stack_depth-- ];
4539 if ($frame & 4) { # Extended exit message
4540 _indent_print_line_info(0, "out ");
4541 print_trace( $LINEINFO, -1, 1, 1, "$sub$al" );
4544 _indent_print_line_info(0, "exited $sub$al\n" );
4549 # Print the return info if we need to.
4550 if ( $doret eq $stack_depth or $frame & 16 ) {
4552 # Turn off output record separator.
4554 my $fh = ( $doret eq $stack_depth ? $OUT : $LINEINFO );
4556 # Indent if we're printing because of $frame tracing.
4559 print {$fh} ' ' x $stack_depth;
4562 # Print the return value.
4563 print {$fh} "list context return from $sub:\n";
4564 dumpit( $fh, \@ret );
4566 # And don't print it again.
4568 } ## end if ($doret eq $stack_depth...
4569 # And we have to return the return value now.
4571 } ## end if (wantarray)
4574 # If we are supposed to show the return value... same as before.
4575 if ( $doret eq $stack_depth or $frame & 16 and defined wantarray ) {
4577 my $fh = ( $doret eq $stack_depth ? $OUT : $LINEINFO );
4578 print $fh ( ' ' x $stack_depth ) if $frame & 16;
4581 ? "scalar context return from $sub: "
4582 : "void context return from $sub\n"
4584 dumpit( $fh, $ret ) if defined wantarray;
4586 } ## end if ($doret eq $stack_depth...
4588 # Return the appropriate scalar value.
4590 } ## end else [ if (wantarray)
4596 # We stack the stack pointer and then increment it to protect us
4597 # from a situation that might unwind a whole bunch of call frames
4598 # at once. Localizing the stack pointer means that it will automatically
4599 # unwind the same amount when multiple stack frames are unwound.
4600 local $stack_depth = $stack_depth + 1; # Protect from non-local exits
4603 $#stack = $stack_depth;
4605 # Save current single-step setting.
4606 $stack[-1] = $single;
4608 # Turn off all flags except single-stepping.
4609 # Use local so the single-step value is popped back off the
4611 local $single = $single & 1;
4615 # lock ourselves under threads
4618 # Whether or not the autoloader was running, a scalar to put the
4619 # sub's return value in (if needed), and an array to put the sub's
4620 # return value in (if needed).
4621 my ( $al, $ret, @ret ) = "";
4622 if ($sub =~ /^threads::new$/ && $ENV{PERL5DB_THREADED}) {
4623 print "creating new thread\n";
4626 # If the last ten characters are C'::AUTOLOAD', note we've traced
4627 # into AUTOLOAD for $sub.
4628 if ( length($sub) > 10 && substr( $sub, -10, 10 ) eq '::AUTOLOAD' ) {
4632 # If we've gotten really deeply recursed, turn on the flag that will
4633 # make us stop with the 'deep recursion' message.
4634 $single |= 4 if $stack_depth == $deep;
4636 # If frame messages are on ...
4637 _print_frame_message($al);
4640 # call the original lvalue sub.
4644 # Abstracting common code from multiple places elsewhere:
4645 sub depth_print_lineinfo {
4646 my $always_print = shift;
4648 print_lineinfo( @_ ) if ($always_print or $stack_depth < $trace_to_depth);
4651 =head1 EXTENDED COMMAND HANDLING AND THE COMMAND API
4653 In Perl 5.8.0, there was a major realignment of the commands and what they did,
4654 Most of the changes were to systematize the command structure and to eliminate
4655 commands that threw away user input without checking.
4657 The following sections describe the code added to make it easy to support
4658 multiple command sets with conflicting command names. This section is a start
4659 at unifying all command processing to make it simpler to develop commands.
4661 Note that all the cmd_[a-zA-Z] subroutines require the command name, a line
4662 number, and C<$dbline> (the current line) as arguments.
4664 Support functions in this section which have multiple modes of failure C<die>
4665 on error; the rest simply return a false value.
4667 The user-interface functions (all of the C<cmd_*> functions) just output
4672 The C<%set> hash defines the mapping from command letter to subroutine
4675 C<%set> is a two-level hash, indexed by set name and then by command name.
4676 Note that trying to set the CommandSet to C<foobar> simply results in the
4677 5.8.0 command set being used, since there's no top-level entry for C<foobar>.
4686 'A' => 'pre580_null',
4688 'B' => 'pre580_null',
4689 'd' => 'pre580_null',
4692 'M' => 'pre580_null',
4694 'o' => 'pre580_null',
4700 '<' => 'pre590_prepost',
4701 '<<' => 'pre590_prepost',
4702 '>' => 'pre590_prepost',
4703 '>>' => 'pre590_prepost',
4704 '{' => 'pre590_prepost',
4705 '{{' => 'pre590_prepost',
4709 my %breakpoints_data;
4711 sub _has_breakpoint_data_ref {
4712 my ($filename, $line) = @_;
4715 exists( $breakpoints_data{$filename} )
4717 exists( $breakpoints_data{$filename}{$line} )
4721 sub _get_breakpoint_data_ref {
4722 my ($filename, $line) = @_;
4724 return ($breakpoints_data{$filename}{$line} ||= +{});
4727 sub _delete_breakpoint_data_ref {
4728 my ($filename, $line) = @_;
4730 delete($breakpoints_data{$filename}{$line});
4731 if (! scalar(keys( %{$breakpoints_data{$filename}} )) ) {
4732 delete($breakpoints_data{$filename});
4738 sub _set_breakpoint_enabled_status {
4739 my ($filename, $line, $status) = @_;
4741 _get_breakpoint_data_ref($filename, $line)->{'enabled'} =
4748 sub _enable_breakpoint_temp_enabled_status {
4749 my ($filename, $line) = @_;
4751 _get_breakpoint_data_ref($filename, $line)->{'temp_enabled'} = 1;
4756 sub _cancel_breakpoint_temp_enabled_status {
4757 my ($filename, $line) = @_;
4759 my $ref = _get_breakpoint_data_ref($filename, $line);
4761 delete ($ref->{'temp_enabled'});
4764 _delete_breakpoint_data_ref($filename, $line);
4770 sub _is_breakpoint_enabled {
4771 my ($filename, $line) = @_;
4773 my $data_ref = _get_breakpoint_data_ref($filename, $line);
4774 return ($data_ref->{'enabled'} || $data_ref->{'temp_enabled'});
4777 =head2 C<cmd_wrapper()> (API)
4779 C<cmd_wrapper()> allows the debugger to switch command sets
4780 depending on the value of the C<CommandSet> option.
4782 It tries to look up the command in the C<%set> package-level I<lexical>
4783 (which means external entities can't fiddle with it) and create the name of
4784 the sub to call based on the value found in the hash (if it's there). I<All>
4785 of the commands to be handled in a set have to be added to C<%set>; if they
4786 aren't found, the 5.8.0 equivalent is called (if there is one).
4788 This code uses symbolic references.
4795 my $dblineno = shift;
4797 # Assemble the command subroutine's name by looking up the
4798 # command set and command name in %set. If we can't find it,
4799 # default to the older version of the command.
4801 . ( $set{$CommandSet}{$cmd}
4802 || ( $cmd =~ /\A[<>{]+/o ? 'prepost' : $cmd ) );
4804 # Call the command subroutine, call it by name.
4805 return __PACKAGE__->can($call)->( $cmd, $line, $dblineno );
4806 } ## end sub cmd_wrapper
4808 =head3 C<cmd_a> (command)
4810 The C<a> command handles pre-execution actions. These are associated with a
4811 particular line, so they're stored in C<%dbline>. We default to the current
4812 line if none is specified.
4818 my $line = shift || ''; # [.|line] expr
4821 # If it's dot (here), or not all digits, use the current line.
4822 $line =~ s/\A\./$dbline/;
4824 # Should be a line number followed by an expression.
4825 if ( my ($lineno, $expr) = $line =~ /^\s*(\d*)\s*(\S.+)/ ) {
4827 if (! length($lineno)) {
4831 # If we have an expression ...
4832 if ( length $expr ) {
4834 # ... but the line isn't breakable, complain.
4835 if ( $dbline[$lineno] == 0 ) {
4837 "Line $lineno($dbline[$lineno]) does not have an action?\n";
4841 # It's executable. Record that the line has an action.
4842 $had_breakpoints{$filename} |= 2;
4844 # Remove any action, temp breakpoint, etc.
4845 $dbline{$lineno} =~ s/\0[^\0]*//;
4847 # Add the action to the line.
4848 $dbline{$lineno} .= "\0" . action($expr);
4850 _set_breakpoint_enabled_status($filename, $lineno, 1);
4852 } ## end if (length $expr)
4853 } ## end if ($line =~ /^\s*(\d*)\s*(\S.+)/)
4858 "Adding an action requires an optional lineno and an expression\n"
4863 =head3 C<cmd_A> (command)
4865 Delete actions. Similar to above, except the delete code is in a separate
4866 subroutine, C<delete_action>.
4872 my $line = shift || '';
4876 $line =~ s/^\./$dbline/;
4878 # Call delete_action with a null param to delete them all.
4879 # The '1' forces the eval to be true. It'll be false only
4880 # if delete_action blows up for some reason, in which case
4881 # we print $@ and get out.
4882 if ( $line eq '*' ) {
4883 if (! eval { _delete_all_actions(); 1 }) {
4889 # There's a real line number. Pass it to delete_action.
4890 # Error trapping is as above.
4891 elsif ( $line =~ /^(\S.*)/ ) {
4892 if (! eval { delete_action($1); 1 }) {
4898 # Swing and a miss. Bad syntax.
4901 "Deleting an action requires a line number, or '*' for all\n" ; # hint
4905 =head3 C<delete_action> (API)
4907 C<delete_action> accepts either a line number or C<undef>. If a line number
4908 is specified, we check for the line being executable (if it's not, it
4909 couldn't have had an action). If it is, we just take the action off (this
4910 will get any kind of an action, including breakpoints).
4914 sub _remove_action_from_dbline {
4917 $dbline{$i} =~ s/\0[^\0]*//; # \^a
4918 delete $dbline{$i} if $dbline{$i} eq '';
4923 sub _delete_all_actions {
4924 print {$OUT} "Deleting all actions...\n";
4926 for my $file ( keys %had_breakpoints ) {
4927 local *dbline = $main::{ '_<' . $file };
4930 for my $i (1 .. $max) {
4931 if ( defined $dbline{$i} ) {
4932 _remove_action_from_dbline($i);
4936 unless ( $had_breakpoints{$file} &= ~2 ) {
4937 delete $had_breakpoints{$file};
4947 if ( defined($i) ) {
4949 die "Line $i has no action .\n" if $dbline[$i] == 0;
4951 # Nuke whatever's there.
4952 _remove_action_from_dbline($i);
4955 _delete_all_actions();
4959 =head3 C<cmd_b> (command)
4961 Set breakpoints. Since breakpoints can be set in so many places, in so many
4962 ways, conditionally or not, the breakpoint code is kind of complex. Mostly,
4963 we try to parse the command type, and then shuttle it off to an appropriate
4964 subroutine to actually do the work of setting the breakpoint in the right
4971 my $line = shift; # [.|line] [cond]
4974 my $default_cond = sub {
4976 return length($cond) ? $cond : '1';
4979 # Make . the current line number if it's there..
4980 $line =~ s/^\.(\s|\z)/$dbline$1/;
4982 # No line number, no condition. Simple break on current line.
4983 if ( $line =~ /^\s*$/ ) {
4984 cmd_b_line( $dbline, 1 );
4987 # Break on load for a file.
4988 elsif ( my ($file) = $line =~ /^load\b\s*(.*)/ ) {
4993 # b compile|postpone <some sub> [<condition>]
4994 # The interpreter actually traps this one for us; we just put the
4995 # necessary condition in the %postponed hash.
4996 elsif ( my ($action, $subname, $cond)
4997 = $line =~ /^(postpone|compile)\b\s*([':A-Za-z_][':\w]*)\s*(.*)/ ) {
4999 # De-Perl4-ify the name - ' separators to ::.
5000 $subname =~ s/'/::/g;
5002 # Qualify it into the current package unless it's already qualified.
5003 $subname = "${package}::" . $subname unless $subname =~ /::/;
5005 # Add main if it starts with ::.
5006 $subname = "main" . $subname if substr( $subname, 0, 2 ) eq "::";
5008 # Save the break type for this sub.
5009 $postponed{$subname} = (($action eq 'postpone')
5010 ? ( "break +0 if " . $default_cond->($cond) )
5012 } ## end elsif ($line =~ ...
5013 # b <filename>:<line> [<condition>]
5014 elsif (my ($filename, $line_num, $cond)
5015 = $line =~ /\A(\S+[^:]):(\d+)\s*(.*)/ms) {
5016 cmd_b_filename_line(
5019 (length($cond) ? $cond : '1'),
5022 # b <sub name> [<condition>]
5023 elsif ( my ($new_subname, $new_cond) =
5024 $line =~ /^([':A-Za-z_][':\w]*(?:\[.*\])?)\s*(.*)/ ) {
5027 $subname = $new_subname;
5028 cmd_b_sub( $subname, $default_cond->($new_cond) );
5031 # b <line> [<condition>].
5032 elsif ( my ($line_n, $cond) = $line =~ /^(\d*)\s*(.*)/ ) {
5034 # Capture the line. If none, it's the current line.
5035 $line = $line_n || $dbline;
5038 cmd_b_line( $line, $default_cond->($cond) );
5041 # Line didn't make sense.
5043 print "confused by line($line)?\n";
5049 =head3 C<break_on_load> (API)
5051 We want to break when this file is loaded. Mark this file in the
5052 C<%break_on_load> hash, and note that it has a breakpoint in
5053 C<%had_breakpoints>.
5059 $break_on_load{$file} = 1;
5060 $had_breakpoints{$file} |= 1;
5063 =head3 C<report_break_on_load> (API)
5065 Gives us an array of filenames that are set to break on load. Note that
5066 only files with break-on-load are in here, so simply showing the keys
5071 sub report_break_on_load {
5072 sort keys %break_on_load;
5075 =head3 C<cmd_b_load> (command)
5077 We take the file passed in and try to find it in C<%INC> (which maps modules
5078 to files they came from). We mark those files for break-on-load via
5079 C<break_on_load> and then report that it was done.
5087 # This is a block because that way we can use a redo inside it
5088 # even without there being any looping structure at all outside it.
5091 # Save short name and full path if found.
5093 push @files, $::INC{$file} if $::INC{$file};
5095 # Tack on .pm and do it again unless there was a '.' in the name
5097 $file .= '.pm', redo unless $file =~ /\./;
5100 # Do the real work here.
5101 break_on_load($_) for @files;
5103 # All the files that have break-on-load breakpoints.
5104 @files = report_break_on_load;
5106 # Normalize for the purposes of our printing this.
5109 print $OUT "Will stop on load of '@files'.\n";
5110 } ## end sub cmd_b_load
5112 =head3 C<$filename_error> (API package global)
5114 Several of the functions we need to implement in the API need to work both
5115 on the current file and on other files. We don't want to duplicate code, so
5116 C<$filename_error> is used to contain the name of the file that's being
5117 worked on (if it's not the current one).
5119 We can now build functions in pairs: the basic function works on the current
5120 file, and uses C<$filename_error> as part of its error message. Since this is
5121 initialized to C<"">, no filename will appear when we are working on the
5124 The second function is a wrapper which does the following:
5130 Localizes C<$filename_error> and sets it to the name of the file to be processed.
5134 Localizes the C<*dbline> glob and reassigns it to point to the file we want to process.
5138 Calls the first function.
5140 The first function works on the I<current> file (i.e., the one we changed to),
5141 and prints C<$filename_error> in the error message (the name of the other file)
5142 if it needs to. When the functions return, C<*dbline> is restored to point
5143 to the actual current file (the one we're executing in) and
5144 C<$filename_error> is restored to C<"">. This restores everything to
5145 the way it was before the second function was called at all.
5147 See the comments in L<S<C<sub breakable_line>>|/breakable_line(from, to) (API)>
5149 L<S<C<sub breakable_line_in_filename>>|/breakable_line_in_filename(file, from, to) (API)>
5156 use vars qw($filename_error);
5157 $filename_error = '';
5159 =head3 breakable_line(from, to) (API)
5161 The subroutine decides whether or not a line in the current file is breakable.
5162 It walks through C<@dbline> within the range of lines specified, looking for
5163 the first line that is breakable.
5165 If C<$to> is greater than C<$from>, the search moves forwards, finding the
5166 first line I<after> C<$to> that's breakable, if there is one.
5168 If C<$from> is greater than C<$to>, the search goes I<backwards>, finding the
5169 first line I<before> C<$to> that's breakable, if there is one.
5173 sub breakable_line {
5175 my ( $from, $to ) = @_;
5177 # $i is the start point. (Where are the FORTRAN programs of yesteryear?)
5180 # If there are at least 2 arguments, we're trying to search a range.
5183 # $delta is positive for a forward search, negative for a backward one.
5184 my $delta = $from < $to ? +1 : -1;
5186 # Keep us from running off the ends of the file.
5187 my $limit = $delta > 0 ? $#dbline : 1;
5189 # Clever test. If you're a mathematician, it's obvious why this
5190 # test works. If not:
5191 # If $delta is positive (going forward), $limit will be $#dbline.
5192 # If $to is less than $limit, ($limit - $to) will be positive, times
5193 # $delta of 1 (positive), so the result is > 0 and we should use $to
5194 # as the stopping point.
5196 # If $to is greater than $limit, ($limit - $to) is negative,
5197 # times $delta of 1 (positive), so the result is < 0 and we should
5198 # use $limit ($#dbline) as the stopping point.
5200 # If $delta is negative (going backward), $limit will be 1.
5201 # If $to is zero, ($limit - $to) will be 1, times $delta of -1
5202 # (negative) so the result is > 0, and we use $to as the stopping
5205 # If $to is less than zero, ($limit - $to) will be positive,
5206 # times $delta of -1 (negative), so the result is not > 0, and
5207 # we use $limit (1) as the stopping point.
5209 # If $to is 1, ($limit - $to) will zero, times $delta of -1
5210 # (negative), still giving zero; the result is not > 0, and
5211 # we use $limit (1) as the stopping point.
5213 # if $to is >1, ($limit - $to) will be negative, times $delta of -1
5214 # (negative), giving a positive (>0) value, so we'll set $limit to
5217 $limit = $to if ( $limit - $to ) * $delta > 0;
5219 # The real search loop.
5220 # $i starts at $from (the point we want to start searching from).
5221 # We move through @dbline in the appropriate direction (determined
5222 # by $delta: either -1 (back) or +1 (ahead).
5223 # We stay in as long as we haven't hit an executable line
5224 # ($dbline[$i] == 0 means not executable) and we haven't reached
5225 # the limit yet (test similar to the above).
5226 $i += $delta while $dbline[$i] == 0 and ( $limit - $i ) * $delta > 0;
5228 } ## end if (@_ >= 2)
5230 # If $i points to a line that is executable, return that.
5231 return $i unless $dbline[$i] == 0;
5233 # Format the message and print it: no breakable lines in range.
5234 my ( $pl, $upto ) = ( '', '' );
5235 ( $pl, $upto ) = ( 's', "..$to" ) if @_ >= 2 and $from != $to;
5237 # If there's a filename in filename_error, we'll see it.
5239 die "Line$pl $from$upto$filename_error not breakable\n";
5240 } ## end sub breakable_line
5242 =head3 breakable_line_in_filename(file, from, to) (API)
5244 Like C<breakable_line>, but look in another file.
5248 sub breakable_line_in_filename {
5250 # Capture the file name.
5253 # Swap the magic line array over there temporarily.
5254 local *dbline = $main::{ '_<' . $f };
5256 # If there's an error, it's in this other file.
5257 local $filename_error = " of '$f'";
5259 # Find the breakable line.
5262 # *dbline and $filename_error get restored when this block ends.
5264 } ## end sub breakable_line_in_filename
5266 =head3 break_on_line(lineno, [condition]) (API)
5268 Adds a breakpoint with the specified condition (or 1 if no condition was
5269 specified) to the specified line. Dies if it can't.
5275 my $cond = @_ ? shift(@_) : 1;
5281 # Woops, not a breakable line. $filename_error allows us to say
5282 # if it was in a different file.
5283 die "Line $i$filename_error not breakable.\n" if $dbline[$i] == 0;
5285 # Mark this file as having breakpoints in it.
5286 $had_breakpoints{$filename} |= 1;
5288 # If there is an action or condition here already ...
5289 if ( $dbline{$i} ) {
5291 # ... swap this condition for the existing one.
5292 $dbline{$i} =~ s/^[^\0]*/$cond/;
5296 # Nothing here - just add the condition.
5297 $dbline{$i} = $cond;
5299 _set_breakpoint_enabled_status($filename, $i, 1);
5303 } ## end sub break_on_line
5305 =head3 cmd_b_line(line, [condition]) (command)
5307 Wrapper for C<break_on_line>. Prints the failure message if it
5313 if (not eval { break_on_line(@_); 1 }) {
5315 print $OUT $@ and return;
5319 } ## end sub cmd_b_line
5321 =head3 cmd_b_filename_line(line, [condition]) (command)
5323 Wrapper for C<break_on_filename_line>. Prints the failure message if it
5328 sub cmd_b_filename_line {
5329 if (not eval { break_on_filename_line(@_); 1 }) {
5331 print $OUT $@ and return;
5337 =head3 break_on_filename_line(file, line, [condition]) (API)
5339 Switches to the file specified and then calls C<break_on_line> to set
5344 sub break_on_filename_line {
5347 my $cond = @_ ? shift(@_) : 1;
5349 # Switch the magical hash temporarily.
5350 local *dbline = $main::{ '_<' . $f };
5352 # Localize the variables that break_on_line uses to make its message.
5353 local $filename_error = " of '$f'";
5354 local $filename = $f;
5356 # Add the breakpoint.
5357 break_on_line( $i, $cond );
5360 } ## end sub break_on_filename_line
5362 =head3 break_on_filename_line_range(file, from, to, [condition]) (API)
5364 Switch to another file, search the range of lines specified for an
5365 executable one, and put a breakpoint on the first one you find.
5369 sub break_on_filename_line_range {
5373 my $cond = @_ ? shift(@_) : 1;
5375 # Find a breakable line if there is one.
5376 my $i = breakable_line_in_filename( $f, $from, $to );
5378 # Add the breakpoint.
5379 break_on_filename_line( $f, $i, $cond );
5382 } ## end sub break_on_filename_line_range
5384 =head3 subroutine_filename_lines(subname, [condition]) (API)
5386 Search for a subroutine within a given file. The condition is ignored.
5387 Uses C<find_sub> to locate the desired subroutine.
5391 sub subroutine_filename_lines {
5392 my ( $subname ) = @_;
5394 # Returned value from find_sub() is fullpathname:startline-endline.
5395 # The match creates the list (fullpathname, start, end).
5396 return (find_sub($subname) =~ /^(.*):(\d+)-(\d+)$/);
5397 } ## end sub subroutine_filename_lines
5399 =head3 break_subroutine(subname) (API)
5401 Places a break on the first line possible in the specified subroutine. Uses
5402 C<subroutine_filename_lines> to find the subroutine, and
5403 C<break_on_filename_line_range> to place the break.
5407 sub break_subroutine {
5408 my $subname = shift;
5410 # Get filename, start, and end.
5411 my ( $file, $s, $e ) = subroutine_filename_lines($subname)
5412 or die "Subroutine $subname not found.\n";
5415 # Null condition changes to '1' (always true).
5416 my $cond = @_ ? shift(@_) : 1;
5418 # Put a break the first place possible in the range of lines
5419 # that make up this subroutine.
5420 break_on_filename_line_range( $file, $s, $e, $cond );
5423 } ## end sub break_subroutine
5425 =head3 cmd_b_sub(subname, [condition]) (command)
5427 We take the incoming subroutine name and fully-qualify it as best we can.
5431 =item 1. If it's already fully-qualified, leave it alone.
5433 =item 2. Try putting it in the current package.
5435 =item 3. If it's not there, try putting it in CORE::GLOBAL if it exists there.
5437 =item 4. If it starts with '::', put it in 'main::'.
5441 After all this cleanup, we call C<break_subroutine> to try to set the
5447 my $subname = shift;
5448 my $cond = @_ ? shift : 1;
5450 # If the subname isn't a code reference, qualify it so that
5451 # break_subroutine() will work right.
5452 if ( ref($subname) ne 'CODE' ) {
5455 $subname =~ s/'/::/g;
5458 # Put it in this package unless it's already qualified.
5459 if ($subname !~ /::/)
5461 $subname = $package . '::' . $subname;
5464 # Requalify it into CORE::GLOBAL if qualifying it into this
5465 # package resulted in its not being defined, but only do so
5466 # if it really is in CORE::GLOBAL.
5467 my $core_name = "CORE::GLOBAL::$s";
5468 if ((!defined(&$subname))
5470 and (defined &{$core_name}))
5472 $subname = $core_name;
5475 # Put it in package 'main' if it has a leading ::.
5476 if ($subname =~ /\A::/)
5478 $subname = "main" . $subname;
5480 } ## end if ( ref($subname) ne 'CODE' ) {
5482 # Try to set the breakpoint.
5483 if (not eval { break_subroutine( $subname, $cond ); 1 }) {
5490 } ## end sub cmd_b_sub
5492 =head3 C<cmd_B> - delete breakpoint(s) (command)
5494 The command mostly parses the command line and tries to turn the argument
5495 into a line spec. If it can't, it uses the current line. It then calls
5496 C<delete_breakpoint> to actually do the work.
5498 If C<*> is specified, C<cmd_B> calls C<delete_breakpoint> with no arguments,
5499 thereby deleting all the breakpoints.
5506 # No line spec? Use dbline.
5507 # If there is one, use it if it's non-zero, or wipe it out if it is.
5508 my $line = ( $_[0] =~ /\A\./ ) ? $dbline : (shift || '');
5511 # If the line was dot, make the line the current one.
5512 $line =~ s/^\./$dbline/;
5514 # If it's * we're deleting all the breakpoints.
5515 if ( $line eq '*' ) {
5516 if (not eval { delete_breakpoint(); 1 }) {
5521 # If there is a line spec, delete the breakpoint on that line.
5522 elsif ( $line =~ /\A(\S.*)/ ) {
5523 if (not eval { delete_breakpoint( $line || $dbline ); 1 }) {
5527 } ## end elsif ($line =~ /^(\S.*)/)
5532 "Deleting a breakpoint requires a line number, or '*' for all\n"
5539 =head3 delete_breakpoint([line]) (API)
5541 This actually does the work of deleting either a single breakpoint, or all
5544 For a single line, we look for it in C<@dbline>. If it's nonbreakable, we
5545 just drop out with a message saying so. If it is, we remove the condition
5546 part of the 'condition\0action' that says there's a breakpoint here. If,
5547 after we've done that, there's nothing left, we delete the corresponding
5548 line in C<%dbline> to signal that no action needs to be taken for this line.
5550 For all breakpoints, we iterate through the keys of C<%had_breakpoints>,
5551 which lists all currently-loaded files which have breakpoints. We then look
5552 at each line in each of these files, temporarily switching the C<%dbline>
5553 and C<@dbline> structures to point to the files in question, and do what
5554 we did in the single line case: delete the condition in C<@dbline>, and
5555 delete the key in C<%dbline> if nothing's left.
5557 We then wholesale delete C<%postponed>, C<%postponed_file>, and
5558 C<%break_on_load>, because these structures contain breakpoints for files
5559 and code that haven't been loaded yet. We can just kill these off because there
5560 are no magical debugger structures associated with them.
5564 sub _remove_breakpoint_entry {
5568 _delete_breakpoint_data_ref($fn, $i);
5573 sub _delete_all_breakpoints {
5574 print {$OUT} "Deleting all breakpoints...\n";
5576 # %had_breakpoints lists every file that had at least one
5578 for my $fn ( keys %had_breakpoints ) {
5580 # Switch to the desired file temporarily.
5581 local *dbline = $main::{ '_<' . $fn };
5585 # For all lines in this file ...
5586 for my $i (1 .. $max) {
5588 # If there's a breakpoint or action on this line ...
5589 if ( defined $dbline{$i} ) {
5591 # ... remove the breakpoint.
5592 $dbline{$i} =~ s/\A[^\0]+//;
5593 if ( $dbline{$i} =~ s/\A\0?\z// ) {
5594 # Remove the entry altogether if no action is there.
5595 _remove_breakpoint_entry($fn, $i);
5597 } ## end if (defined $dbline{$i...
5598 } ## end for $i (1 .. $max)
5600 # If, after we turn off the "there were breakpoints in this file"
5601 # bit, the entry in %had_breakpoints for this file is zero,
5602 # we should remove this file from the hash.
5603 if ( not $had_breakpoints{$fn} &= (~1) ) {
5604 delete $had_breakpoints{$fn};
5606 } ## end for my $fn (keys %had_breakpoints)
5608 # Kill off all the other breakpoints that are waiting for files that
5609 # haven't been loaded yet.
5611 undef %postponed_file;
5612 undef %break_on_load;
5617 sub _delete_breakpoint_from_line {
5620 # Woops. This line wasn't breakable at all.
5621 die "Line $i not breakable.\n" if $dbline[$i] == 0;
5623 # Kill the condition, but leave any action.
5624 $dbline{$i} =~ s/\A[^\0]*//;
5626 # Remove the entry entirely if there's no action left.
5627 if ($dbline{$i} eq '') {
5628 _remove_breakpoint_entry($filename, $i);
5634 sub delete_breakpoint {
5637 # If we got a line, delete just that one.
5638 if ( defined($i) ) {
5639 _delete_breakpoint_from_line($i);
5641 # No line; delete them all.
5643 _delete_all_breakpoints();
5649 =head3 cmd_stop (command)
5651 This is meant to be part of the new command API, but it isn't called or used
5652 anywhere else in the debugger. XXX It is probably meant for use in development
5657 sub cmd_stop { # As on ^C, but not signal-safy.
5661 =head3 C<cmd_e> - threads
5663 Display the current thread id:
5667 This could be how (when implemented) to send commands to this thread id (e cmd)
5668 or that thread id (e tid cmd).
5675 unless (exists($INC{'threads.pm'})) {
5676 print "threads not loaded($ENV{PERL5DB_THREADED})
5677 please run the debugger with PERL5DB_THREADED=1 set in the environment\n";
5679 my $tid = threads->tid;
5680 print "thread id: $tid\n";
5684 =head3 C<cmd_E> - list of thread ids
5686 Display the list of available thread ids:
5690 This could be used (when implemented) to send commands to all threads (E cmd).
5697 unless (exists($INC{'threads.pm'})) {
5698 print "threads not loaded($ENV{PERL5DB_THREADED})
5699 please run the debugger with PERL5DB_THREADED=1 set in the environment\n";
5701 my $tid = threads->tid;
5702 print "thread ids: ".join(', ',
5703 map { ($tid == $_->tid ? '<'.$_->tid.'>' : $_->tid) } threads->list
5708 =head3 C<cmd_h> - help command (command)
5710 Does the work of either
5716 Showing all the debugger help
5720 Showing help for a specific command
5727 use vars qw($summary);
5732 # If we have no operand, assume null.
5733 my $line = shift || '';
5735 # 'h h'. Print the long-format help.
5736 if ( $line =~ /\Ah\s*\z/ ) {
5740 # 'h <something>'. Search for the command and print only its help.
5741 elsif ( my ($asked) = $line =~ /\A(\S.*)\z/ ) {
5743 # support long commands; otherwise bogus errors
5744 # happen when you ask for h on <CR> for example
5745 my $qasked = quotemeta($asked); # for searching; we don't
5746 # want to use it as a pattern.
5747 # XXX: finds CR but not <CR>
5749 # Search the help string for the command.
5751 $help =~ /^ # Start of a line
5753 (?:[IB]<) # Optional markup
5754 $qasked # The requested command
5759 # It's there; pull it out and print it.
5763 (?:[IB]<) # Optional markup
5764 $qasked # The command
5765 ([\s\S]*?) # Description line(s)
5766 \n) # End of last description line
5767 (?!\s) # Next line not starting with
5776 # Not found; not a debugger command.
5778 print_help("B<$asked> is not a debugger command.\n");
5780 } ## end elsif ($line =~ /^(\S.*)$/)
5782 # 'h' - print the summary help.
5784 print_help($summary);
5788 =head3 C<cmd_L> - list breakpoints, actions, and watch expressions (command)
5790 To list breakpoints, the command has to look determine where all of them are
5791 first. It starts a C<%had_breakpoints>, which tells us what all files have
5792 breakpoints and/or actions. For each file, we switch the C<*dbline> glob (the
5793 magic source and breakpoint data structures) to the file, and then look
5794 through C<%dbline> for lines with breakpoints and/or actions, listing them
5795 out. We look through C<%postponed> not-yet-compiled subroutines that have
5796 breakpoints, and through C<%postponed_file> for not-yet-C<require>'d files
5797 that have breakpoints.
5799 Watchpoints are simpler: we just list the entries in C<@to_watch>.
5803 sub _cmd_L_calc_arg {
5804 # If no argument, list everything. Pre-5.8.0 version always lists
5806 my $arg = shift || 'abw';
5807 if ($CommandSet ne '580')
5815 sub _cmd_L_calc_wanted_flags {
5816 my $arg = _cmd_L_calc_arg(shift);
5818 return (map { index($arg, $_) >= 0 ? 1 : 0 } qw(a b w));
5822 sub _cmd_L_handle_breakpoints {
5823 my ($handle_db_line) = @_;
5826 # Look in all the files with breakpoints...
5827 for my $file ( keys %had_breakpoints ) {
5829 # Temporary switch to this file.
5830 local *dbline = $main::{ '_<' . $file };
5832 # Set up to look through the whole file.
5834 my $was; # Flag: did we print something
5837 # For each line in the file ...
5838 for my $i (1 .. $max) {
5840 # We've got something on this line.
5841 if ( defined $dbline{$i} ) {
5843 # Print the header if we haven't.
5845 print {$OUT} "$file:\n";
5849 print {$OUT} " $i:\t", $dbline[$i];
5851 $handle_db_line->($dbline{$i});
5853 # Quit if the user hit interrupt.
5855 last BREAKPOINTS_SCAN;
5857 } ## end if (defined $dbline{$i...
5858 } ## end for my $i (1 .. $max)
5859 } ## end for my $file (keys %had_breakpoints)
5864 sub _cmd_L_handle_postponed_breakpoints {
5865 my ($handle_db_line) = @_;
5867 print {$OUT} "Postponed breakpoints in files:\n";
5870 for my $file ( keys %postponed_file ) {
5871 my $db = $postponed_file{$file};
5872 print {$OUT} " $file:\n";
5873 for my $line ( sort { $a <=> $b } keys %$db ) {
5874 print {$OUT} " $line:\n";
5876 $handle_db_line->($db->{$line});
5879 last POSTPONED_SCANS;
5883 last POSTPONED_SCANS;
5894 my ($action_wanted, $break_wanted, $watch_wanted) =
5895 _cmd_L_calc_wanted_flags(shift);
5897 my $handle_db_line = sub {
5900 my ( $stop, $action ) = split( /\0/, $l );
5902 if ($stop and $break_wanted) {
5903 print {$OUT} " break if (", $stop, ")\n"
5906 if ($action && $action_wanted) {
5907 print {$OUT} " action: ", $action, "\n"
5913 # Breaks and actions are found together, so we look in the same place
5915 if ( $break_wanted or $action_wanted ) {
5916 _cmd_L_handle_breakpoints($handle_db_line);
5919 # Look for breaks in not-yet-compiled subs:
5920 if ( %postponed and $break_wanted ) {
5921 print {$OUT} "Postponed breakpoints in subroutines:\n";
5924 for $subname ( keys %postponed ) {
5925 print {$OUT} " $subname\t$postponed{$subname}\n";
5930 } ## end if (%postponed and $break_wanted)
5932 # Find files that have not-yet-loaded breaks:
5933 my @have = map { # Combined keys
5934 keys %{ $postponed_file{$_} }
5935 } keys %postponed_file;
5937 # If there are any, list them.
5938 if ( @have and ( $break_wanted or $action_wanted ) ) {
5939 _cmd_L_handle_postponed_breakpoints($handle_db_line);
5940 } ## end if (@have and ($break_wanted...
5942 if ( %break_on_load and $break_wanted ) {
5943 print {$OUT} "Breakpoints on load:\n";
5944 BREAK_ON_LOAD: for my $filename ( keys %break_on_load ) {
5945 print {$OUT} " $filename\n";
5946 last BREAK_ON_LOAD if $signal;
5948 } ## end if (%break_on_load and...
5950 if ($watch_wanted and ( $trace & 2 )) {
5951 print {$OUT} "Watch-expressions:\n" if @to_watch;
5952 TO_WATCH: for my $expr (@to_watch) {
5953 print {$OUT} " $expr\n";
5954 last TO_WATCH if $signal;
5961 =head3 C<cmd_M> - list modules (command)
5963 Just call C<list_modules>.
5973 =head3 C<cmd_o> - options (command)
5975 If this is just C<o> by itself, we list the current settings via
5976 C<dump_option>. If there's a nonblank value following it, we pass that on to
5977 C<parse_options> for processing.
5983 my $opt = shift || ''; # opt[=val]
5985 # Nonblank. Try to parse and process.
5986 if ( $opt =~ /^(\S.*)/ ) {
5990 # Blank. List the current option settings.
5998 =head3 C<cmd_O> - nonexistent in 5.8.x (command)
6000 Advises the user that the O command has been renamed.
6005 print $OUT "The old O command is now the o command.\n"; # hint
6006 print $OUT "Use 'h' to get current command help synopsis or\n"; #
6007 print $OUT "use 'o CommandSet=pre580' to revert to old usage\n"; #
6010 =head3 C<cmd_v> - view window (command)
6012 Uses the C<$preview> variable set in the second C<BEGIN> block (q.v.) to
6013 move back a few lines to list the selected line in context. Uses C<_cmd_l_main>
6014 to do the actual listing after figuring out the range of line to request.
6018 use vars qw($preview);
6024 # Extract the line to list around. (Astute readers will have noted that
6025 # this pattern will match whether or not a numeric line is specified,
6026 # which means that we'll always enter this loop (though a non-numeric
6027 # argument results in no action at all)).
6028 if ( $line =~ /^(\d*)$/ ) {
6030 # Total number of lines to list (a windowful).
6031 $incr = $window - 1;
6033 # Set the start to the argument given (if there was one).
6036 # Back up by the context amount.
6039 # Put together a linespec that _cmd_l_main will like.
6040 $line = $start . '-' . ( $start + $incr );
6043 _cmd_l_main( $line );
6044 } ## end if ($line =~ /^(\d*)$/)
6047 =head3 C<cmd_w> - add a watch expression (command)
6049 The 5.8 version of this command adds a watch expression if one is specified;
6050 it does nothing if entered with no operands.
6052 We extract the expression, save it, evaluate it in the user's context, and
6053 save the value. We'll re-evaluate it each time the debugger passes a line,
6054 and will stop (see the code at the top of the command loop) if the value
6055 of any of the expressions changes.
6059 sub _add_watch_expr {
6063 push @to_watch, $expr;
6065 # Parameterize DB::eval and call it to get the expression's value
6066 # in the user's context. This version can handle expressions which
6067 # return a list value.
6069 # The &-call is here to ascertain the mutability of @_.
6070 my ($val) = join( ' ', &DB::eval);
6071 $val = ( defined $val ) ? "'$val'" : 'undef';
6073 # Save the current value of the expression.
6074 push @old_watch, $val;
6076 # We are now watching expressions.
6085 # Null expression if no arguments.
6086 my $expr = shift || '';
6088 # If expression is not null ...
6089 if ( $expr =~ /\A\S/ ) {
6090 _add_watch_expr($expr);
6091 } ## end if ($expr =~ /^(\S.*)/)
6093 # You have to give one to get one.
6095 print $OUT "Adding a watch-expression requires an expression\n"; # hint
6101 =head3 C<cmd_W> - delete watch expressions (command)
6103 This command accepts either a watch expression to be removed from the list
6104 of watch expressions, or C<*> to delete them all.
6106 If C<*> is specified, we simply empty the watch expression list and the
6107 watch expression value list. We also turn off the bit that says we've got
6110 If an expression (or partial expression) is specified, we pattern-match
6111 through the expressions and remove the ones that match. We also discard
6112 the corresponding values. If no watch expressions are left, we turn off
6113 the I<watching expressions> bit.
6119 my $expr = shift || '';
6122 if ( $expr eq '*' ) {
6127 print $OUT "Deleting all watch expressions ...\n";
6130 @to_watch = @old_watch = ();
6133 # Delete one of them.
6134 elsif ( $expr =~ /^(\S.*)/ ) {
6136 # Where we are in the list.
6139 # For each expression ...
6140 foreach (@to_watch) {
6141 my $val = $to_watch[$i_cnt];
6143 # Does this one match the command argument?
6144 if ( $val eq $expr ) { # =~ m/^\Q$i$/) {
6145 # Yes. Turn it off, and its value too.
6146 splice( @to_watch, $i_cnt, 1 );
6147 splice( @old_watch, $i_cnt, 1 );
6150 } ## end foreach (@to_watch)
6152 # We don't bother to turn watching off because
6153 # a) we don't want to stop calling watchfunction() if it exists
6154 # b) foreach over a null list doesn't do anything anyway
6156 } ## end elsif ($expr =~ /^(\S.*)/)
6158 # No command arguments entered.
6161 "Deleting a watch-expression requires an expression, or '*' for all\n"
6166 ### END of the API section
6168 =head1 SUPPORT ROUTINES
6170 These are general support routines that are used in a number of places
6171 throughout the debugger.
6175 save() saves the user's versions of globals that would mess us up in C<@saved>,
6176 and installs the versions we like better.
6182 # Save eval failure, command failure, extended OS error, output field
6183 # separator, input record separator, output record separator and
6184 # the warning setting.
6185 @saved = ( $@, $!, $^E, $,, $/, $\, $^W );
6187 $, = ""; # output field separator is null string
6188 $/ = "\n"; # input record separator is newline
6189 $\ = ""; # output record separator is null string
6190 $^W = 0; # warnings are off
6193 =head2 C<print_lineinfo> - show where we are now
6195 print_lineinfo prints whatever it is that it is handed; it prints it to the
6196 C<$LINEINFO> filehandle instead of just printing it to STDOUT. This allows
6197 us to feed line information to a client editor without messing up the
6202 sub print_lineinfo {
6204 # Make the terminal sensible if we're not the primary debugger.
6205 resetterm(1) if $LINEINFO eq $OUT and $term_pid != $$;
6208 # $LINEINFO may be undef if $noTTY is set or some other issue.
6211 print {$LINEINFO} @_;
6213 } ## end sub print_lineinfo
6215 =head2 C<postponed_sub>
6217 Handles setting postponed breakpoints in subroutines once they're compiled.
6218 For breakpoints, we use C<DB::find_sub> to locate the source file and line
6219 range for the subroutine, then mark the file as having a breakpoint,
6220 temporarily switch the C<*dbline> glob over to the source file, and then
6221 search the given range of lines to find a breakable line. If we find one,
6222 we set the breakpoint on it, deleting the breakpoint from C<%postponed>.
6226 # The following takes its argument via $evalarg to preserve current @_
6230 # Get the subroutine name.
6231 my $subname = shift;
6233 # If this is a 'break +<n> if <condition>' ...
6234 if ( $postponed{$subname} =~ s/^break\s([+-]?\d+)\s+if\s// ) {
6236 # If there's no offset, use '+0'.
6237 my $offset = $1 || 0;
6239 # find_sub's value is 'fullpath-filename:start-stop'. It's
6240 # possible that the filename might have colons in it too.
6241 my ( $file, $i ) = ( find_sub($subname) =~ /^(.*):(\d+)-.*$/ );
6244 # We got the start line. Add the offset '+<n>' from
6245 # $postponed{subname}.
6248 # Switch to the file this sub is in, temporarily.
6249 local *dbline = $main::{ '_<' . $file };
6251 # No warnings, please.
6252 local $^W = 0; # != 0 is magical below
6254 # This file's got a breakpoint in it.
6255 $had_breakpoints{$file} |= 1;
6257 # Last line in file.
6260 # Search forward until we hit a breakable line or get to
6261 # the end of the file.
6262 ++$i until $dbline[$i] != 0 or $i >= $max;
6264 # Copy the breakpoint in and delete it from %postponed.
6265 $dbline{$i} = delete $postponed{$subname};
6268 # find_sub didn't find the sub.
6271 print $OUT "Subroutine $subname not found.\n";
6274 } ## end if ($postponed{$subname...
6275 elsif ( $postponed{$subname} eq 'compile' ) { $signal = 1 }
6277 #print $OUT "In postponed_sub for '$subname'.\n";
6278 } ## end sub postponed_sub
6282 Called after each required file is compiled, but before it is executed;
6283 also called if the name of a just-compiled subroutine is a key of
6284 C<%postponed>. Propagates saved breakpoints (from S<C<b compile>>,
6285 S<C<b load>>, etc.) into the just-compiled code.
6287 If this is a C<require>'d file, the incoming parameter is the glob
6288 C<*{"_<$filename"}>, with C<$filename> the name of the C<require>'d file.
6290 If it's a subroutine, the incoming parameter is the subroutine name.
6296 # If there's a break, process it.
6297 if ($ImmediateStop) {
6299 # Right, we've stopped. Turn it off.
6302 # Enter the command loop when DB::DB gets called.
6306 # If this is a subroutine, let postponed_sub() deal with it.
6307 if (ref(\$_[0]) ne 'GLOB') {
6308 return postponed_sub(@_);
6311 # Not a subroutine. Deal with the file.
6312 local *dbline = shift;
6313 my $filename = $dbline;
6314 $filename =~ s/^_<//;
6316 $signal = 1, print $OUT "'$filename' loaded...\n"
6317 if $break_on_load{$filename};
6318 print_lineinfo( ' ' x $stack_depth, "Package $filename.\n" ) if $frame;
6320 # Do we have any breakpoints to put in this file?
6321 return unless $postponed_file{$filename};
6323 # Yes. Mark this file as having breakpoints.
6324 $had_breakpoints{$filename} |= 1;
6326 # "Cannot be done: insufficient magic" - we can't just put the
6327 # breakpoints saved in %postponed_file into %dbline by assigning
6328 # the whole hash; we have to do it one item at a time for the
6329 # breakpoints to be set properly.
6330 #%dbline = %{$postponed_file{$filename}};
6332 # Set the breakpoints, one at a time.
6335 for $key ( keys %{ $postponed_file{$filename} } ) {
6337 # Stash the saved breakpoint into the current file's magic line array.
6338 $dbline{$key} = ${ $postponed_file{$filename} }{$key};
6341 # This file's been compiled; discard the stored breakpoints.
6342 delete $postponed_file{$filename};
6344 } ## end sub postponed
6348 C<dumpit> is the debugger's wrapper around dumpvar.pl.
6350 It gets a filehandle (to which C<dumpvar.pl>'s output will be directed) and
6351 a reference to a variable (the thing to be dumped) as its input.
6353 The incoming filehandle is selected for output (C<dumpvar.pl> is printing to
6354 the currently-selected filehandle, thank you very much). The current
6355 values of the package globals C<$single> and C<$trace> are backed up in
6356 lexicals, and they are turned off (this keeps the debugger from trying
6357 to single-step through C<dumpvar.pl> (I think.)). C<$frame> is localized to
6358 preserve its current value and it is set to zero to prevent entry/exit
6359 messages from printing, and C<$doret> is localized as well and set to -2 to
6360 prevent return values from being shown.
6362 C<dumpit()> then checks to see if it needs to load C<dumpvar.pl> and
6363 tries to load it (note: if you have a C<dumpvar.pl> ahead of the
6364 installed version in C<@INC>, yours will be used instead. Possible security
6367 It then checks to see if the subroutine C<main::dumpValue> is now defined
6368 it should have been defined by C<dumpvar.pl>). If it has, C<dumpit()>
6369 localizes the globals necessary for things to be sane when C<main::dumpValue()>
6370 is called, and picks up the variable to be dumped from the parameter list.
6372 It checks the package global C<%options> to see if there's a C<dumpDepth>
6373 specified. If not, -1 is assumed; if so, the supplied value gets passed on to
6374 C<dumpvar.pl>. This tells C<dumpvar.pl> where to leave off when dumping a
6375 structure: -1 means dump everything.
6377 C<dumpValue()> is then called if possible; if not, C<dumpit()>just prints a
6380 In either case, C<$single>, C<$trace>, C<$frame>, and C<$doret> are restored
6381 and we then return to the caller.
6387 # Save the current output filehandle and switch to the one
6388 # passed in as the first parameter.
6389 my $savout = select(shift);
6391 # Save current settings of $single and $trace, and then turn them off.
6392 my $osingle = $single;
6393 my $otrace = $trace;
6394 $single = $trace = 0;
6396 # XXX Okay, what do $frame and $doret do, again?
6400 # Load dumpvar.pl unless we've already got the sub we need from it.
6401 unless ( defined &main::dumpValue ) {
6402 do 'dumpvar.pl' or die $@;
6405 # If the load succeeded (or we already had dumpvalue()), go ahead
6407 if ( defined &main::dumpValue ) {
6412 my $maxdepth = shift || $option{dumpDepth};
6413 $maxdepth = -1 unless defined $maxdepth; # -1 means infinite depth
6414 main::dumpValue( $v, $maxdepth );
6415 } ## end if (defined &main::dumpValue)
6417 # Oops, couldn't load dumpvar.pl.
6420 print $OUT "dumpvar.pl not available.\n";
6423 # Reset $single and $trace to their old values.
6427 # Restore the old filehandle.
6431 =head2 C<print_trace>
6433 C<print_trace>'s job is to print a stack trace. It does this via the
6434 C<dump_trace> routine, which actually does all the ferreting-out of the
6435 stack trace data. C<print_trace> takes care of formatting it nicely and
6436 printing it to the proper filehandle.
6444 The filehandle to print to.
6448 How many frames to skip before starting trace.
6452 How many frames to print.
6456 A flag: if true, print a I<short> trace without filenames, line numbers, or arguments
6460 The original comment below seems to be noting that the traceback may not be
6461 correct if this routine is called in a tied method.
6465 # Tied method do not create a context, so may get wrong message:
6471 # If this is going to a client editor, but we're not the primary
6472 # debugger, reset it first.
6474 if $fh eq $LINEINFO # client editor
6475 and $LINEINFO eq $OUT # normal output
6476 and $term_pid != $$; # not the primary
6478 # Collect the actual trace information to be formatted.
6479 # This is an array of hashes of subroutine call info.
6480 my @sub = dump_trace( $_[0] + 1, $_[1] );
6482 # Grab the "short report" flag from @_.
6483 my $short = $_[2]; # Print short report, next one for sub name
6485 # Run through the traceback info, format it, and print it.
6487 for my $i (0 .. $#sub) {
6489 # Drop out if the user has lost interest and hit control-C.
6492 # Set the separator so arrays print nice.
6495 # Grab and stringify the arguments if they are there.
6497 defined $sub[$i]{args}
6498 ? "(@{ $sub[$i]{args} })"
6501 # Shorten them up if $maxtrace says they're too long.
6502 $args = ( substr $args, 0, $maxtrace - 3 ) . '...'
6503 if length $args > $maxtrace;
6505 # Get the file name.
6506 my $file = $sub[$i]{file};
6508 # Put in a filename header if short is off.
6509 $file = $file eq '-e' ? $file : "file '$file'" unless $short;
6511 # Get the actual sub's name, and shorten to $maxtrace's requirement.
6512 $s = $sub[$i]{'sub'};
6513 $s = ( substr $s, 0, $maxtrace - 3 ) . '...' if length $s > $maxtrace;
6515 # Short report uses trimmed file and sub names.
6517 my $sub = @_ >= 4 ? $_[3] : $s;
6518 print $fh "$sub[$i]{context}=$sub$args from $file:$sub[$i]{line}\n";
6519 } ## end if ($short)
6521 # Non-short report includes full names.
6523 print $fh "$sub[$i]{context} = $s$args"
6524 . " called from $file"
6525 . " line $sub[$i]{line}\n";
6527 } ## end for my $i (0 .. $#sub)
6528 } ## end sub print_trace
6530 =head2 dump_trace(skip[,count])
6532 Actually collect the traceback information available via C<caller()>. It does
6533 some filtering and cleanup of the data, but mostly it just collects it to
6534 make C<print_trace()>'s job easier.
6536 C<skip> defines the number of stack frames to be skipped, working backwards
6537 from the most current. C<count> determines the total number of frames to
6538 be returned; all of them (well, the first 10^9) are returned if C<count>
6541 This routine returns a list of hashes, from most-recent to least-recent
6542 stack frame. Each has the following keys and values:
6546 =item * C<context> - C<.> (null), C<$> (scalar), or C<@> (array)
6548 =item * C<sub> - subroutine name, or C<eval> information
6550 =item * C<args> - undef, or a reference to an array of arguments
6552 =item * C<file> - the file in which this item was defined (if any)
6554 =item * C<line> - the line on which it was defined
6560 sub _dump_trace_calc_saved_single_arg
6562 my ($nothard, $arg) = @_;
6565 if ( not defined $arg ) { # undefined parameter
6569 elsif ( $nothard and tied $arg ) { # tied parameter
6572 elsif ( $nothard and $type = ref $arg ) { # reference
6573 return "ref($type)";
6575 else { # can be stringified
6577 "$arg"; # Safe to stringify now - should not call f().
6579 # Backslash any single-quotes or backslashes.
6582 # Single-quote it unless it's a number or a colon-separated
6585 unless /^(?: -?[\d.]+ | \*[\w:]* )$/x;
6587 # Turn high-bit characters into meta-whatever, and controls into like
6589 require 'meta_notation.pm';
6590 $_ = _meta_notation($_) if /[[:^print:]]/a;
6596 sub _dump_trace_calc_save_args {
6600 map { _dump_trace_calc_saved_single_arg($nothard, $_) } @args
6606 # How many levels to skip.
6609 # How many levels to show. (1e9 is a cheap way of saying "all of them";
6610 # it's unlikely that we'll have more than a billion stack frames. If you
6611 # do, you've got an awfully big machine...)
6612 my $count = shift || 1e9;
6614 # We increment skip because caller(1) is the first level *back* from
6615 # the current one. Add $skip to the count of frames so we have a
6616 # simple stop criterion, counting from $skip to $count+$skip.
6620 # These variables are used to capture output from caller();
6621 my ( $p, $file, $line, $sub, $h, $context );
6623 my ( $e, $r, @sub, $args );
6625 # XXX Okay... why'd we do that?
6626 my $nothard = not $frame & 8;
6629 # Do not want to trace this.
6630 my $otrace = $trace;
6633 # Start out at the skip count.
6634 # If we haven't reached the number of frames requested, and caller() is
6635 # still returning something, stay in the loop. (If we pass the requested
6636 # number of stack frames, or we run out - caller() returns nothing - we
6638 # Up the stack frame index to go back one more level each time.
6642 and ( $p, $file, $line, $sub, $h, $context, $e, $r ) = caller($i) ;
6646 # if the sub has args ($h true), make an anonymous array of the
6648 my $args = $h ? _dump_trace_calc_save_args($nothard) : undef;
6650 # If context is true, this is array (@)context.
6651 # If context is false, this is scalar ($) context.
6652 # If neither, context isn't defined. (This is apparently a 'can't
6654 $context = $context ? '@' : ( defined $context ? "\$" : '.' );
6656 # remove trailing newline-whitespace-semicolon-end of line sequence
6657 # from the eval text, if any.
6658 $e =~ s/\n\s*\;\s*\Z// if $e;
6660 # Escape backslashed single-quotes again if necessary.
6661 $e =~ s/([\\\'])/\\$1/g if $e;
6663 # if the require flag is true, the eval text is from a require.
6665 $sub = "require '$e'";
6668 # if it's false, the eval text is really from an eval.
6669 elsif ( defined $r ) {
6673 # If the sub is '(eval)', this is a block eval, meaning we don't
6674 # know what the eval'ed text actually was.
6675 elsif ( $sub eq '(eval)' ) {
6676 $sub = "eval {...}";
6679 # Stick the collected information into @sub as an anonymous hash.
6683 context => $context,
6691 # Stop processing frames if the user hit control-C.
6693 } ## end for ($i = $skip ; $i < ...
6695 # Restore the trace value again.
6698 } ## end sub dump_trace
6702 C<action()> takes input provided as the argument to an add-action command,
6703 either pre- or post-, and makes sure it's a complete command. It doesn't do
6704 any fancy parsing; it just keeps reading input until it gets a string
6705 without a trailing backslash.
6712 while ( $action =~ s/\\$// ) {
6714 # We have a backslash on the end. Read more.
6716 } ## end while ($action =~ s/\\$//)
6718 # Return the assembled action.
6724 This routine mostly just packages up a regular expression to be used
6725 to check that the thing it's being matched against has properly-matched
6728 Of note is the definition of the C<$balanced_brace_re> global via C<||=>, which
6729 speeds things up by only creating the qr//'ed expression once; if it's
6730 already defined, we don't try to define it again. A speed hack.
6734 use vars qw($balanced_brace_re);
6738 # I hate using globals!
6739 $balanced_brace_re ||= qr{
6742 (?> [^{}] + ) # Non-parens without backtracking
6744 (??{ $balanced_brace_re }) # Group with matching parens
6748 return $_[0] !~ m/$balanced_brace_re/;
6749 } ## end sub unbalanced
6753 C<gets()> is a primitive (very primitive) routine to read continuations.
6754 It was devised for reading continuations for actions.
6755 it just reads more input with C<readline()> and returns it.
6760 return DB::readline("cont: ");
6763 =head2 C<_db_system()> - handle calls to<system()> without messing up the debugger
6765 The C<system()> function assumes that it can just go ahead and use STDIN and
6766 STDOUT, but under the debugger, we want it to use the debugger's input and
6769 C<_db_system()> socks away the program's STDIN and STDOUT, and then substitutes
6770 the debugger's IN and OUT filehandles for them. It does the C<system()> call,
6771 and then puts everything back again.
6777 # We save, change, then restore STDIN and STDOUT to avoid fork() since
6778 # some non-Unix systems can do system() but have problems with fork().
6779 open( SAVEIN, "<&STDIN" ) || _db_warn("Can't save STDIN");
6780 open( SAVEOUT, ">&STDOUT" ) || _db_warn("Can't save STDOUT");
6781 open( STDIN, "<&IN" ) || _db_warn("Can't redirect STDIN");
6782 open( STDOUT, ">&OUT" ) || _db_warn("Can't redirect STDOUT");
6784 # XXX: using csh or tcsh destroys sigint retvals!
6786 open( STDIN, "<&SAVEIN" ) || _db_warn("Can't restore STDIN");
6787 open( STDOUT, ">&SAVEOUT" ) || _db_warn("Can't restore STDOUT");
6791 # most of the $? crud was coping with broken cshisms
6793 _db_warn( "(Command exited ", ( $? >> 8 ), ")\n" );
6797 "(Command died of SIG#",
6799 ( ( $? & 128 ) ? " -- core dumped" : "" ),
6808 *system = \&_db_system;
6810 =head1 TTY MANAGEMENT
6812 The subs here do some of the terminal management for multiple debuggers.
6816 Top-level function called when we want to set up a new terminal for use
6819 If the C<noTTY> debugger option was set, we'll either use the terminal
6820 supplied (the value of the C<noTTY> option), or we'll use C<Term::Rendezvous>
6821 to find one. If we're a forked debugger, we call C<resetterm> to try to
6822 get a whole new terminal if we can.
6824 In either case, we set up the terminal next. If the C<ReadLine> option was
6825 true, we'll get a C<Term::ReadLine> object for the current terminal and save
6826 the appropriate attributes. We then
6830 use vars qw($ornaments);
6831 use vars qw($rl_attribs);
6835 # Load Term::Readline, but quietly; don't debug it and don't trace it.
6838 require Term::ReadLine;
6840 # If noTTY is set, but we have a TTY name, go ahead and hook up to it.
6843 my ( $i, $o ) = split $tty, /,/;
6844 $o = $i unless defined $o;
6845 open( IN, '<', $i ) or die "Cannot open TTY '$i' for read: $!";
6846 open( OUT, '>', $o ) or die "Cannot open TTY '$o' for write: $!";
6852 # We don't have a TTY - try to find one via Term::Rendezvous.
6854 require Term::Rendezvous;
6856 # See if we have anything to pass to Term::Rendezvous.
6857 # Use $HOME/.perldbtty$$ if not.
6858 my $rv = $ENV{PERLDB_NOTTY} || "$ENV{HOME}/.perldbtty$$";
6860 # Rendezvous and get the filehandles.
6861 my $term_rv = Term::Rendezvous->new( $rv );
6863 $OUT = $term_rv->OUT;
6864 } ## end else [ if ($tty)
6865 } ## end if ($notty)
6867 # We're a daughter debugger. Try to fork off another TTY.
6868 if ( $term_pid eq '-1' ) { # In a TTY with another debugger
6872 # If we shouldn't use Term::ReadLine, don't.
6874 $term = Term::ReadLine::Stub->new( 'perldb', $IN, $OUT );
6877 # We're using Term::ReadLine. Get all the attributes for this terminal.
6879 $term = Term::ReadLine->new( 'perldb', $IN, $OUT );
6881 $rl_attribs = $term->Attribs;
6882 $rl_attribs->{basic_word_break_characters} .= '-:+/*,[])}'
6883 if defined $rl_attribs->{basic_word_break_characters}
6884 and index( $rl_attribs->{basic_word_break_characters}, ":" ) == -1;
6885 $rl_attribs->{special_prefixes} = '$@&%';
6886 $rl_attribs->{completer_word_break_characters} .= '$@&%';
6887 $rl_attribs->{completion_function} = \&db_complete;
6888 } ## end else [ if (!$rl)
6890 # Set up the LINEINFO filehandle.
6891 $LINEINFO = $OUT unless defined $LINEINFO;
6892 $lineinfo = $console unless defined $lineinfo;
6898 if ( $term->Features->{setHistory} and "@hist" ne "?" ) {
6899 $term->SetHistory(@hist);
6902 # XXX Ornaments are turned on unconditionally, which is not
6903 # always a good thing.
6904 ornaments($ornaments) if defined $ornaments;
6906 } ## end sub setterm
6909 $histfile //= option_val("HistFile", undef);
6910 return unless defined $histfile;
6911 open my $fh, "<", $histfile or return;
6922 return unless defined $histfile;
6923 eval { require File::Path } or return;
6924 eval { require File::Basename } or return;
6925 File::Path::mkpath(File::Basename::dirname($histfile));
6926 open my $fh, ">", $histfile or die "Could not open '$histfile': $!";
6927 $histsize //= option_val("HistSize",100);
6928 my @copy = grep { $_ ne '?' } @hist;
6929 my $start = scalar(@copy) > $histsize ? scalar(@copy)-$histsize : 0;
6930 for ($start .. $#copy) {
6931 print $fh "$copy[$_]\n";
6933 close $fh or die "Could not write '$histfile': $!";
6936 =head1 GET_FORK_TTY EXAMPLE FUNCTIONS
6938 When the process being debugged forks, or the process invokes a command
6939 via C<system()> which starts a new debugger, we need to be able to get a new
6940 C<IN> and C<OUT> filehandle for the new debugger. Otherwise, the two processes
6941 fight over the terminal, and you can never quite be sure who's going to get the
6942 input you're typing.
6944 C<get_fork_TTY> is a glob-aliased function which calls the real function that
6945 is tasked with doing all the necessary operating system mojo to get a new
6946 TTY (and probably another window) and to direct the new debugger to read and
6949 The debugger provides C<get_fork_TTY> functions which work for TCP
6950 socket servers, X11, OS/2, and Mac OS X. Other systems are not
6951 supported. You are encouraged to write C<get_fork_TTY> functions which
6952 work for I<your> platform and contribute them.
6954 =head3 C<socket_get_fork_TTY>
6958 sub connect_remoteport {
6961 my $socket = IO::Socket::INET->new(
6963 PeerAddr => $remoteport,
6967 die "Unable to connect to remote host: $remoteport\n";
6972 sub socket_get_fork_TTY {
6973 $tty = $LINEINFO = $IN = $OUT = connect_remoteport();
6975 # Do I need to worry about setting $term?
6977 reset_IN_OUT( $IN, $OUT );
6981 =head3 C<xterm_get_fork_TTY>
6983 This function provides the C<get_fork_TTY> function for X11. If a
6984 program running under the debugger forks, a new <xterm> window is opened and
6985 the subsidiary debugger is directed there.
6987 The C<open()> call is of particular note here. We have the new C<xterm>
6988 we're spawning route file number 3 to STDOUT, and then execute the C<tty>
6989 command (which prints the device name of the TTY we'll want to use for input
6990 and output to STDOUT, then C<sleep> for a very long time, routing this output
6991 to file number 3. This way we can simply read from the <XT> filehandle (which
6992 is STDOUT from the I<commands> we ran) to get the TTY we want to use.
6994 Only works if C<xterm> is in your path and C<$ENV{DISPLAY}>, etc. are
6999 sub xterm_get_fork_TTY {
7000 ( my $name = $0 ) =~ s,^.*[/\\],,s;
7002 qq[3>&1 xterm -title "Daughter Perl debugger $pids $name" -e sh -c 'tty 1>&3;\
7005 # Get the output from 'tty' and clean it up a little.
7009 $pidprompt = ''; # Shown anyway in titlebar
7011 # We need $term defined or we can not switch to the newly created xterm
7012 if ($tty ne '' && !defined $term) {
7013 require Term::ReadLine;
7015 $term = Term::ReadLine::Stub->new( 'perldb', $IN, $OUT );
7018 $term = Term::ReadLine->new( 'perldb', $IN, $OUT );
7021 # There's our new TTY.
7023 } ## end sub xterm_get_fork_TTY
7025 =head3 C<os2_get_fork_TTY>
7027 XXX It behooves an OS/2 expert to write the necessary documentation for this!
7031 # This example function resets $IN, $OUT itself
7033 sub os2_get_fork_TTY { # A simplification of the following (and works without):
7035 ( my $name = $0 ) =~ s,^.*[/\\],,s;
7036 my %opt = ( title => "Daughter Perl debugger $pids $name",
7037 ($rl ? (read_by_key => 1) : ()) );
7038 require OS2::Process;
7039 my ($in, $out, $pid) = eval { OS2::Process::io_term(related => 0, %opt) }
7041 $pidprompt = ''; # Shown anyway in titlebar
7042 reset_IN_OUT($in, $out);
7044 return ''; # Indicate that reset_IN_OUT is called
7045 } ## end sub os2_get_fork_TTY
7047 =head3 C<macosx_get_fork_TTY>
7049 The Mac OS X version uses AppleScript to tell Terminal.app to create
7054 # Notes about Terminal.app's AppleScript support,
7055 # (aka things that might break in future OS versions).
7057 # The "do script" command doesn't return a reference to the new window
7058 # it creates, but since it appears frontmost and windows are enumerated
7059 # front to back, we can use "first window" === "window 1".
7061 # Since "do script" is implemented by supplying the argument (plus a
7062 # return character) as terminal input, there's a potential race condition
7063 # where the debugger could beat the shell to reading the command.
7064 # To prevent this, we wait for the screen to clear before proceeding.
7067 # There's no direct accessor for the tty device name, so we fiddle
7068 # with the window title options until it says what we want.
7071 # There _is_ a direct accessor for the tty device name, _and_ there's
7072 # a new possible component of the window title (the name of the settings
7073 # set). A separate version is needed.
7075 my @script_versions=
7077 ([237, <<'__LEOPARD__'],
7078 tell application "Terminal"
7079 do script "clear;exec sleep 100000"
7080 tell first tab of first window
7082 set custom title to "forked perl debugger"
7083 set title displays custom title to true
7084 repeat while (length of first paragraph of (get contents)) > 0
7092 [100, <<'__JAGUAR_TIGER__'],
7093 tell application "Terminal"
7094 do script "clear;exec sleep 100000"
7096 set title displays shell path to false
7097 set title displays window size to false
7098 set title displays file name to false
7099 set title displays device name to true
7100 set title displays custom title to true
7101 set custom title to ""
7102 copy "/dev/" & name to thetty
7103 set custom title to "forked perl debugger"
7104 repeat while (length of first paragraph of (get contents)) > 0
7114 sub macosx_get_fork_TTY
7116 my($version,$script,$pipe,$tty);
7118 return unless $version=$ENV{TERM_PROGRAM_VERSION};
7119 foreach my $entry (@script_versions) {
7120 if ($version>=$entry->[0]) {
7121 $script=$entry->[1];
7125 return unless defined($script);
7126 return unless open($pipe,'-|','/usr/bin/osascript','-e',$script);
7127 $tty=readline($pipe);
7129 return unless defined($tty) && $tty =~ m(^/dev/);
7134 =head3 C<tmux_get_fork_TTY>
7136 Creates a split window for subprocesses when a process running under the
7137 perl debugger in Tmux forks.
7141 sub tmux_get_fork_TTY {
7142 return unless $ENV{TMUX};
7146 my $status = open $pipe, '-|', 'tmux', 'split-window',
7147 '-P', '-F', '#{pane_tty}', 'sleep 100000';
7159 if ( !defined $term ) {
7160 require Term::ReadLine;
7162 $term = Term::ReadLine::Stub->new( 'perldb', $IN, $OUT );
7165 $term = Term::ReadLine->new( 'perldb', $IN, $OUT );
7173 =head2 C<create_IN_OUT($flags)>
7175 Create a new pair of filehandles, pointing to a new TTY. If impossible,
7176 try to diagnose why.
7182 =item * 1 - Don't know how to create a new TTY.
7184 =item * 2 - Debugger has forked, but we can't get a new TTY.
7186 =item * 4 - standard debugger startup is happening.
7192 use vars qw($fork_TTY);
7194 sub create_IN_OUT { # Create a window with IN/OUT handles redirected there
7196 # If we know how to get a new TTY, do it! $in will have
7197 # the TTY name if get_fork_TTY works.
7198 my $in = get_fork_TTY(@_) if defined &get_fork_TTY;
7200 # It used to be that
7201 $in = $fork_TTY if defined $fork_TTY; # Backward compatibility
7203 if ( not defined $in ) {
7206 # We don't know how.
7207 print_help(<<EOP) if $why == 1;
7208 I<#########> Forked, but do not know how to create a new B<TTY>. I<#########>
7212 print_help(<<EOP) if $why == 2;
7213 I<#########> Daughter session, do not know how to change a B<TTY>. I<#########>
7214 This may be an asynchronous session, so the parent debugger may be active.
7217 # Note that both debuggers are fighting over the same input.
7218 print_help(<<EOP) if $why != 4;
7219 Since two debuggers fight for the same TTY, input is severely entangled.
7223 I know how to switch the output to a different window in xterms, OS/2
7224 consoles, and Mac OS X Terminal.app only. For a manual switch, put the name
7225 of the created I<TTY> in B<\$DB::fork_TTY>, or define a function
7226 B<DB::get_fork_TTY()> returning this.
7228 On I<UNIX>-like systems one can get the name of a I<TTY> for the given window
7229 by typing B<tty>, and disconnect the I<shell> from I<TTY> by S<B<sleep 1000000>>.
7232 } ## end if (not defined $in)
7233 elsif ( $in ne '' ) {
7237 $console = ''; # Indicate no need to open-from-the-console
7240 } ## end sub create_IN_OUT
7244 Handles rejiggering the prompt when we've forked off a new debugger.
7246 If the new debugger happened because of a C<system()> that invoked a
7247 program under the debugger, the arrow between the old pid and the new
7248 in the prompt has I<two> dashes instead of one.
7250 We take the current list of pids and add this one to the end. If there
7251 isn't any list yet, we make one up out of the initial pid associated with
7252 the terminal and our new pid, sticking an arrow (either one-dashed or
7253 two dashed) in between them.
7255 If C<CreateTTY> is off, or C<resetterm> was called with no arguments,
7256 we don't try to create a new IN and OUT filehandle. Otherwise, we go ahead
7261 sub resetterm { # We forked, so we need a different TTY
7263 # Needs to be passed to create_IN_OUT() as well.
7266 # resetterm(2): got in here because of a system() starting a debugger.
7267 # resetterm(1): just forked.
7268 my $systemed = $in > 1 ? '-' : '';
7270 # If there's already a list of pids, add this to the end.
7272 $pids =~ s/\]/$systemed->$$]/;
7275 # No pid list. Time to make one.
7277 $pids = "[$term_pid->$$]";
7280 # The prompt we're going to be using for this debugger.
7283 # We now 0wnz this terminal.
7286 # Just return if we're not supposed to try to create a new TTY.
7287 return unless $CreateTTY & $in;
7289 # Try to create a new IN/OUT pair.
7291 } ## end sub resetterm
7295 First, we handle stuff in the typeahead buffer. If there is any, we shift off
7296 the next line, print a message saying we got it, add it to the terminal
7297 history (if possible), and return it.
7299 If there's nothing in the typeahead buffer, check the command filehandle stack.
7300 If there are any filehandles there, read from the last one, and return the line
7301 if we got one. If not, we pop the filehandle off and close it, and try the
7302 next one up the stack.
7304 If we've emptied the filehandle stack, we check to see if we've got a socket
7305 open, and we read that and return it if we do. If we don't, we just call the
7306 core C<readline()> and return its value.
7312 # Localize to prevent it from being smashed in the program being debugged.
7315 # If there are stacked filehandles to read from ...
7316 # (Handle it before the typeahead, because we may call source/etc. from
7320 # Read from the last one in the stack.
7321 my $line = CORE::readline( $cmdfhs[-1] );
7323 # If we got a line ...
7325 ? ( print $OUT ">> $line" and return $line ) # Echo and return
7326 : close pop @cmdfhs; # Pop and close
7327 } ## end while (@cmdfhs)
7329 # Pull a line out of the typeahead if there's stuff there.
7332 # How many lines left.
7333 my $left = @typeahead;
7335 # Get the next line.
7336 my $got = shift @typeahead;
7338 # Print a message saying we got input from the typeahead.
7340 print $OUT "auto(-$left)", shift, $got, "\n";
7342 # Add it to the terminal history (if possible).
7343 $term->AddHistory($got)
7344 if length($got) >= option_val("HistItemMinLength", 2)
7345 and defined $term->Features->{addHistory};
7347 } ## end if (@typeahead)
7349 # We really need to read some input. Turn off entry/exit trace and
7350 # return value printing.
7354 # Nothing on the filehandle stack. Socket?
7355 if ( ref $OUT and UNIVERSAL::isa( $OUT, 'IO::Socket::INET' ) ) {
7357 # Send anything we have to send.
7358 $OUT->write( join( '', @_ ) );
7360 # Receive anything there is to receive.
7365 while ($first_time or (length($buf) && ($stuff .= $buf) !~ /\n/))
7368 $IN->recv( $buf = '', 2048 ); # XXX "what's wrong with sysread?"
7369 # XXX Don't know. You tell me.
7374 } ## end if (ref $OUT and UNIVERSAL::isa...
7376 # No socket. Just read from the terminal.
7378 return $term->readline(@_);
7380 } ## end sub readline
7382 =head1 OPTIONS SUPPORT ROUTINES
7384 These routines handle listing and setting option values.
7386 =head2 C<dump_option> - list the current value of an option setting
7388 This routine uses C<option_val> to look up the value for an option.
7389 It cleans up escaped single-quotes and then displays the option and
7395 my ( $opt, $val ) = @_;
7396 $val = option_val( $opt, 'N/A' );
7397 $val =~ s/([\\\'])/\\$1/g;
7398 printf $OUT "%20s = '%s'\n", $opt, $val;
7399 } ## end sub dump_option
7401 sub options2remember {
7402 foreach my $k (@RememberOnROptions) {
7403 $option{$k} = option_val( $k, 'N/A' );
7408 =head2 C<option_val> - find the current value of an option
7410 This can't just be a simple hash lookup because of the indirect way that
7411 the option values are stored. Some are retrieved by calling a subroutine,
7412 some are just variables.
7414 You must supply a default value to be used in case the option isn't set.
7419 my ( $opt, $default ) = @_;
7422 # Does this option exist, and is it a variable?
7423 # If so, retrieve the value via the value in %optionVars.
7424 if ( defined $optionVars{$opt}
7425 and defined ${ $optionVars{$opt} } )
7427 $val = ${ $optionVars{$opt} };
7430 # Does this option exist, and it's a subroutine?
7431 # If so, call the subroutine via the ref in %optionAction
7432 # and capture the value.
7433 elsif ( defined $optionAction{$opt}
7434 and defined &{ $optionAction{$opt} } )
7436 $val = &{ $optionAction{$opt} }();
7439 # If there's an action or variable for the supplied option,
7440 # but no value was set, use the default.
7441 elsif (defined $optionAction{$opt} and not defined $option{$opt}
7442 or defined $optionVars{$opt} and not defined ${ $optionVars{$opt} } )
7447 # Otherwise, do the simple hash lookup.
7449 $val = $option{$opt};
7452 # If the value isn't defined, use the default.
7453 # Then return whatever the value is.
7454 $val = $default unless defined $val;
7456 } ## end sub option_val
7458 =head2 C<parse_options>
7460 Handles the parsing and execution of option setting/displaying commands.
7462 An option entered by itself is assumed to be I<set me to 1> (the default value)
7463 if the option is a boolean one. If not, the user is prompted to enter a valid
7464 value or to query the current value (via C<option? >).
7466 If C<option=value> is entered, we try to extract a quoted string from the
7467 value (if it is quoted). If it's not, we just use the whole value as-is.
7469 We load any modules required to service this option, and then we set it: if
7470 it just gets stuck in a variable, we do that; if there's a subroutine to
7471 handle setting the option, we call that.
7473 Finally, if we're running in interactive mode, we display the effect of the
7474 user's command back to the terminal, skipping this if we're setting things
7475 during initialization.
7485 # These options need a value. Don't allow them to be clobbered by accident.
7486 my %opt_needs_val = map { ( $_ => 1 ) } qw{
7487 dumpDepth arrayDepth hashDepth LineInfo maxTraceLen ornaments windowSize
7488 pager quote ReadLine recallCommand RemotePort ShellBang TTY CommandSet
7491 while (length($s)) {
7494 # Clean off excess leading whitespace.
7495 $s =~ s/^\s+// && next;
7497 # Options are always all word characters, followed by a non-word
7499 if ($s !~ s/^(\w+)(\W?)//) {
7500 print {$OUT} "Invalid option '$s'\n";
7503 my ( $opt, $sep ) = ( $1, $2 );
7505 # Make sure that such an option exists.
7506 my $matches = ( grep { /^\Q$opt/ && ( $option = $_ ) } @options )
7507 || ( grep { /^\Q$opt/i && ( $option = $_ ) } @options );
7510 print {$OUT} "Unknown option '$opt'\n";
7514 print {$OUT} "Ambiguous option '$opt'\n";
7519 # '?' as separator means query, but must have whitespace after it.
7520 if ( "?" eq $sep ) {
7522 print {$OUT} "Option query '$opt?' followed by non-space '$s'\n" ;
7527 #&dump_option($opt);
7528 } ## end if ("?" eq $sep)
7530 # Separator is whitespace (or just a carriage return).
7531 # They're going for a default, which we assume is 1.
7532 elsif ( $sep !~ /\S/ ) {
7534 $val = "1"; # this is an evil default; make 'em set it!
7537 # Separator is =. Trying to set a value.
7538 elsif ( $sep eq "=" ) {
7540 # If quoted, extract a quoted string.
7541 if ($s =~ s/ (["']) ( (?: \\. | (?! \1 ) [^\\] )* ) \1 //x) {
7543 ( $val = $2 ) =~ s/\\([$quote\\])/$1/g;
7546 # Not quoted. Use the whole thing. Warn about 'option='.
7550 print OUT qq(Option better cleared using $opt=""\n)
7552 } ## end else [ if (s/ (["']) ( (?: \\. | (?! \1 ) [^\\] )* ) \1 //x)
7554 } ## end elsif ($sep eq "=")
7556 # "Quoted" with [], <>, or {}.
7557 else { #{ to "let some poor schmuck bounce on the % key in B<vi>."
7559 "\\" . substr( ")]>}$sep", index( "([<{", $sep ), 1 ); #}
7560 $s =~ s/^(([^\\$end]|\\[\\$end])*)$end($|\s+)//
7561 or print( $OUT "Unclosed option value '$opt$sep$_'\n" ), last;
7562 ( $val = $1 ) =~ s/\\([\\$end])/$1/g;
7563 } ## end else [ if ("?" eq $sep)
7565 # Exclude non-booleans from getting set to 1 by default.
7566 if ( $opt_needs_val{$option} && $val_defaulted ) {
7567 my $cmd = ( $CommandSet eq '580' ) ? 'o' : 'O';
7569 "Option '$opt' is non-boolean. Use '$cmd $option=VAL' to set, '$cmd $option?' to query\n";
7571 } ## end if ($opt_needs_val{$option...
7573 # Save the option value.
7574 $option{$option} = $val if defined $val;
7576 # Load any module that this option requires.
7577 if ( defined($optionRequire{$option}) && defined($val) ) {
7581 require '$optionRequire{$option}';
7583 } || die $@ # XXX: shouldn't happen
7587 # Stick it in the proper variable if it goes in a variable.
7588 if (defined($optionVars{$option}) && defined($val)) {
7589 ${ $optionVars{$option} } = $val;
7592 # Call the appropriate sub if it gets set via sub.
7593 if (defined($optionAction{$option})
7594 && defined (&{ $optionAction{$option} })
7597 &{ $optionAction{$option} }($val);
7600 # Not initialization - echo the value we set it to.
7601 dump_option($option) if ($OUT ne \*STDERR);
7602 } ## end while (length)
7603 } ## end sub parse_options
7605 =head1 RESTART SUPPORT
7607 These routines are used to store (and restore) lists of items in environment
7608 variables during a restart.
7612 Set_list packages up items to be stored in a set of environment variables
7613 (VAR_n, containing the number of items, and VAR_0, VAR_1, etc., containing
7614 the values). Values outside the standard ASCII charset are stored by encoding
7615 them as hexadecimal values.
7620 my ( $stem, @list ) = @_;
7623 # VAR_n: how many we have. Scalar assignment gets the number of items.
7624 $ENV{"${stem}_n"} = @list;
7626 # Grab each item in the list, escape the backslashes, encode the non-ASCII
7627 # as hex, and then save in the appropriate VAR_0, VAR_1, etc.
7628 for my $i ( 0 .. $#list ) {
7630 $val =~ s/\\/\\\\/g;
7631 $val =~ s/ ( (?[ [\000-\xFF] & [:^print:] ]) ) /
7632 "\\0x" . unpack('H2',$1)/xaeg;
7633 $ENV{"${stem}_$i"} = $val;
7634 } ## end for $i (0 .. $#list)
7635 } ## end sub set_list
7639 Reverse the set_list operation: grab VAR_n to see how many we should be getting
7640 back, and then pull VAR_0, VAR_1. etc. back out.
7647 my $n = delete $ENV{"${stem}_n"};
7649 for my $i ( 0 .. $n - 1 ) {
7650 $val = delete $ENV{"${stem}_$i"};
7651 $val =~ s/\\((\\)|0x(..))/ $2 ? $2 : pack('H2', $3) /ge;
7655 } ## end sub get_list
7657 =head1 MISCELLANEOUS SIGNAL AND I/O MANAGEMENT
7661 The C<catch()> subroutine is the essence of fast and low-impact. We simply
7662 set an already-existing global scalar variable to a constant value. This
7663 avoids allocating any memory possibly in the middle of something that will
7664 get all confused if we do, particularly under I<unsafe signals>.
7670 return; # Put nothing on the stack - malloc/free land!
7675 C<warn> emits a warning, by joining together its arguments and printing
7676 them, with couple of fillips.
7678 If the composited message I<doesn't> end with a newline, we automatically
7679 add C<$!> and a newline to the end of the message. The subroutine expects $OUT
7680 to be set to the filehandle to be used to output warnings; it makes no
7681 assumptions about what filehandles are available.
7686 my ($msg) = join( "", @_ );
7687 $msg .= ": $!\n" unless $msg =~ /\n$/;
7694 =head1 INITIALIZATION TTY SUPPORT
7696 =head2 C<reset_IN_OUT>
7698 This routine handles restoring the debugger's input and output filehandles
7699 after we've tried and failed to move them elsewhere. In addition, it assigns
7700 the debugger's output filehandle to $LINEINFO if it was already open there.
7705 my $switch_li = $LINEINFO eq $OUT;
7707 # If there's a term and it's able to get a new tty, try to get one.
7708 if ( $term and $term->Features->{newTTY} ) {
7709 ( $IN, $OUT ) = ( shift, shift );
7710 $term->newTTY( $IN, $OUT );
7713 # This term can't get a new tty now. Better luck later.
7715 _db_warn("Too late to set IN/OUT filehandles, enabled on next 'R'!\n");
7718 # Set the filehndles up as they were.
7720 ( $IN, $OUT ) = ( shift, shift );
7723 # Unbuffer the output filehandle.
7726 # Point LINEINFO to the same output filehandle if it was there before.
7727 $LINEINFO = $OUT if $switch_li;
7728 } ## end sub reset_IN_OUT
7730 =head1 OPTION SUPPORT ROUTINES
7732 The following routines are used to process some of the more complicated
7737 Sets the input and output filehandles to the specified files or pipes.
7738 If the terminal supports switching, we go ahead and do it. If not, and
7739 there's already a terminal in place, we save the information to take effect
7742 If there's no terminal yet (for instance, during debugger initialization),
7743 we go ahead and set C<$console> and C<$tty> to the file indicated.
7749 if ( @_ and $term and $term->Features->{newTTY} ) {
7751 # This terminal supports switching to a new TTY.
7752 # Can be a list of two files, or on string containing both names,
7754 # XXX Should this perhaps be an assignment from @_?
7755 my ( $in, $out ) = shift;
7758 # Split list apart if supplied.
7759 ( $in, $out ) = split /,/, $in, 2;
7763 # Use the same file for both input and output.
7767 # Open file onto the debugger's filehandles, if you can.
7768 open IN, '<', $in or die "cannot open '$in' for read: $!";
7769 open OUT, '>', $out or die "cannot open '$out' for write: $!";
7771 # Swap to the new filehandles.
7772 reset_IN_OUT( \*IN, \*OUT );
7774 # Save the setting for later.
7776 } ## end if (@_ and $term and $term...
7778 # Terminal doesn't support new TTY, or doesn't support readline.
7779 # Can't do it now, try restarting.
7781 _db_warn("Too late to set TTY, enabled on next 'R'!\n");
7784 # Useful if done through PERLDB_OPTS:
7785 $console = $tty = shift if @_;
7787 # Return whatever the TTY is.
7793 Sets the C<$notty> global, controlling whether or not the debugger tries to
7794 get a terminal to read from. If called after a terminal is already in place,
7795 we save the value to use it if we're restarted.
7801 _db_warn("Too late to set noTTY, enabled on next 'R'!\n") if @_;
7803 $notty = shift if @_;
7809 Sets the C<$rl> option variable. If 0, we use C<Term::ReadLine::Stub>
7810 (essentially, no C<readline> processing on this I<terminal>). Otherwise, we
7811 use C<Term::ReadLine>. Can't be changed after a terminal's in place; we save
7812 the value in case a restart is done so we can change it then.
7818 _db_warn("Too late to set ReadLine, enabled on next 'R'!\n") if @_;
7822 } ## end sub ReadLine
7824 =head2 C<RemotePort>
7826 Sets the port that the debugger will try to connect to when starting up.
7827 If the terminal's already been set up, we can't do it, but we remember the
7828 setting in case the user does a restart.
7834 _db_warn("Too late to set RemotePort, enabled on next 'R'!\n") if @_;
7836 $remoteport = shift if @_;
7838 } ## end sub RemotePort
7842 Checks with the terminal to see if C<Tk> is running, and returns true or
7843 false. Returns false if the current terminal doesn't support C<readline>.
7848 if ( ${ $term->Features }{tkRunning} ) {
7849 return $term->tkRunning(@_);
7853 print $OUT "tkRunning not supported by current ReadLine package.\n";
7856 } ## end sub tkRunning
7860 Sets nonstop mode. If a terminal's already been set up, it's too late; the
7861 debugger remembers the setting in case you restart, though.
7867 _db_warn("Too late to set up NonStop mode, enabled on next 'R'!\n")
7870 $runnonstop = shift if @_;
7872 } ## end sub NonStop
7876 _db_warn("Some flag changes could not take effect until next 'R'!\n")
7879 $^P = parse_DollarCaretP_flags(shift) if @_;
7880 expand_DollarCaretP_flags($^P);
7885 Set up the C<$pager> variable. Adds a pipe to the front unless there's one
7893 $pager = "|" . $pager unless $pager =~ /^(\+?\>|\|)/;
7900 Sets the shell escape command, and generates a printable copy to be used
7907 # If we got an argument, meta-quote it, and add '\b' if it
7908 # ends in a word character.
7910 $sh = quotemeta shift;
7911 $sh .= "\\b" if $sh =~ /\w$/;
7914 # Generate the printable version for the help:
7915 $psh = $sh; # copy it
7916 $psh =~ s/\\b$//; # Take off trailing \b if any
7917 $psh =~ s/\\(.)/$1/g; # De-escape
7918 $psh; # return the printable version
7919 } ## end sub shellBang
7923 If the terminal has its own ornaments, fetch them. Otherwise accept whatever
7924 was passed as the argument. (This means you can't override the terminal's
7930 if ( defined $term ) {
7932 # We don't want to show warning backtraces, but we do want die() ones.
7933 local $warnLevel = 0;
7934 local $dieLevel = 1;
7936 # No ornaments if the terminal doesn't support them.
7937 if (not $term->Features->{ornaments}) {
7941 return (eval { $term->ornaments(@_) } || '');
7944 # Use what was passed in if we can't determine it ourselves.
7951 } ## end sub ornaments
7953 =head2 C<recallCommand>
7955 Sets the recall command, and builds a printable version which will appear in
7962 # If there is input, metaquote it. Add '\b' if it ends with a word
7965 $rc = quotemeta shift;
7966 $rc .= "\\b" if $rc =~ /\w$/;
7969 # Build it into a printable version.
7970 $prc = $rc; # Copy it
7971 $prc =~ s/\\b$//; # Remove trailing \b
7972 $prc =~ s/\\(.)/$1/g; # Remove escapes
7973 return $prc; # Return the printable version
7974 } ## end sub recallCommand
7976 =head2 C<LineInfo> - where the line number information goes
7978 Called with no arguments, returns the file or pipe that line info should go to.
7980 Called with an argument (a file or a pipe), it opens that onto the
7981 C<LINEINFO> filehandle, unbuffers the filehandle, and then returns the
7982 file or pipe again to the caller.
7990 # If this is a valid "thing to be opened for output", tack a
7991 # '>' onto the front.
7992 my $stream = ( $lineinfo =~ /^(\+?\>|\|)/ ) ? $lineinfo : ">$lineinfo";
7994 # If this is a pipe, the stream points to a client editor.
7995 $client_editor = ( $stream =~ /^\|/ );
7997 my $new_lineinfo_fh;
7998 # Open it up and unbuffer it.
7999 open ($new_lineinfo_fh , $stream )
8000 or _db_warn("Cannot open '$stream' for write");
8001 $LINEINFO = $new_lineinfo_fh;
8002 _autoflush($LINEINFO);
8006 } ## end sub LineInfo
8008 =head1 COMMAND SUPPORT ROUTINES
8010 These subroutines provide functionality for various commands.
8012 =head2 C<list_modules>
8014 For the C<M> command: list modules loaded and their versions.
8015 Essentially just runs through the keys in %INC, picks each package's
8016 C<$VERSION> variable, gets the file name, and formats the information
8021 sub list_modules { # versions
8025 # keys are the "as-loaded" name, values are the fully-qualified path
8026 # to the file itself.
8028 $file = $_; # get the module name
8029 s,\.p[lm]$,,i; # remove '.pl' or '.pm'
8030 s,/,::,g; # change '/' to '::'
8031 s/^perl5db$/DB/; # Special case: debugger
8032 # moves to package DB
8033 s/^Term::ReadLine::readline$/readline/; # simplify readline
8035 # If the package has a $VERSION package global (as all good packages
8036 # should!) decode it and save as partial message.
8037 my $pkg_version = do { no strict 'refs'; ${ $_ . '::VERSION' } };
8038 if ( defined $pkg_version ) {
8039 $version{$file} = "$pkg_version from ";
8042 # Finish up the message with the file the package came from.
8043 $version{$file} .= $INC{$file};
8044 } ## end for (keys %INC)
8046 # Hey, dumpit() formats a hash nicely, so why not use it?
8047 dumpit( $OUT, \%version );
8048 } ## end sub list_modules
8052 Sets up the monster string used to format and print the help.
8054 =head3 HELP MESSAGE FORMAT
8056 The help message is a peculiar format unto itself; it mixes C<pod> I<ornaments>
8057 (C<< B<> >> C<< I<> >>) with tabs to come up with a format that's fairly
8058 easy to parse and portable, but which still allows the help to be a little
8059 nicer than just plain text.
8061 Essentially, you define the command name (usually marked up with C<< B<> >>
8062 and C<< I<> >>), followed by a tab, and then the descriptive text, ending in a
8063 newline. The descriptive text can also be marked up in the same way. If you
8064 need to continue the descriptive text to another line, start that line with
8065 just tabs and then enter the marked-up text.
8067 If you are modifying the help text, I<be careful>. The help-string parser is
8068 not very sophisticated, and if you don't follow these rules it will mangle the
8069 help beyond hope until you fix the string.
8073 use vars qw($pre580_help);
8074 use vars qw($pre580_summary);
8078 # XXX: make sure there are tabs between the command and explanation,
8079 # or print_help will screw up your formatting if you have
8080 # eeevil ornaments enabled. This is an insane mess.
8083 Help is currently only available for the new 5.8 command set.
8084 No help is available for the old command set.
8085 We assume you know what you're doing if you switch to it.
8088 B<s> [I<expr>] Single step [in I<expr>].
8089 B<n> [I<expr>] Next, steps over subroutine calls [in I<expr>].
8090 <B<CR>> Repeat last B<n> or B<s> command.
8091 B<r> Return from current subroutine.
8092 B<c> [I<line>|I<sub>] Continue; optionally inserts a one-time-only breakpoint
8093 at the specified position.
8094 B<l> I<min>B<+>I<incr> List I<incr>+1 lines starting at I<min>.
8095 B<l> I<min>B<->I<max> List lines I<min> through I<max>.
8096 B<l> I<line> List single I<line>.
8097 B<l> I<subname> List first window of lines from subroutine.
8098 B<l> I<\$var> List first window of lines from subroutine referenced by I<\$var>.
8099 B<l> List next window of lines.
8100 B<-> List previous window of lines.
8101 B<v> [I<line>] View window around I<line>.
8102 B<.> Return to the executed line.
8103 B<f> I<filename> Switch to viewing I<filename>. File must be already loaded.
8104 I<filename> may be either the full name of the file, or a regular
8105 expression matching the full file name:
8106 B<f> I</home/me/foo.pl> and B<f> I<oo\\.> may access the same file.
8107 Evals (with saved bodies) are considered to be filenames:
8108 B<f> I<(eval 7)> and B<f> I<eval 7\\b> access the body of the 7th eval
8109 (in the order of execution).
8110 B</>I<pattern>B</> Search forwards for I<pattern>; final B</> is optional.
8111 B<?>I<pattern>B<?> Search backwards for I<pattern>; final B<?> is optional.
8112 B<L> [I<a|b|w>] List actions and or breakpoints and or watch-expressions.
8113 B<S> [[B<!>]I<pattern>] List subroutine names [not] matching I<pattern>.
8114 B<t> [I<n>] Toggle trace mode (to max I<n> levels below current stack depth).
8115 B<t> [I<n>] I<expr> Trace through execution of I<expr>.
8116 B<b> Sets breakpoint on current line)
8117 B<b> [I<line>] [I<condition>]
8118 Set breakpoint; I<line> defaults to the current execution line;
8119 I<condition> breaks if it evaluates to true, defaults to '1'.
8120 B<b> I<subname> [I<condition>]
8121 Set breakpoint at first line of subroutine.
8122 B<b> I<\$var> Set breakpoint at first line of subroutine referenced by I<\$var>.
8123 B<b> B<load> I<filename> Set breakpoint on 'require'ing the given file.
8124 B<b> B<postpone> I<subname> [I<condition>]
8125 Set breakpoint at first line of subroutine after
8127 B<b> B<compile> I<subname>
8128 Stop after the subroutine is compiled.
8129 B<B> [I<line>] Delete the breakpoint for I<line>.
8130 B<B> I<*> Delete all breakpoints.
8131 B<a> [I<line>] I<command>
8132 Set an action to be done before the I<line> is executed;
8133 I<line> defaults to the current execution line.
8134 Sequence is: check for breakpoint/watchpoint, print line
8135 if necessary, do action, prompt user if necessary,
8138 B<A> [I<line>] Delete the action for I<line>.
8139 B<A> I<*> Delete all actions.
8140 B<w> I<expr> Add a global watch-expression.
8142 B<W> I<expr> Delete a global watch-expression.
8143 B<W> I<*> Delete all watch-expressions.
8144 B<V> [I<pkg> [I<vars>]] List some (default all) variables in package (default current).
8145 Use B<~>I<pattern> and B<!>I<pattern> for positive and negative regexps.
8146 B<X> [I<vars>] Same as \"B<V> I<currentpackage> [I<vars>]\".
8147 B<x> I<expr> Evals expression in list context, dumps the result.
8148 B<m> I<expr> Evals expression in list context, prints methods callable
8149 on the first element of the result.
8150 B<m> I<class> Prints methods callable via the given class.
8151 B<M> Show versions of loaded modules.
8152 B<i> I<class> Prints nested parents of given class.
8153 B<e> Display current thread id.
8154 B<E> Display all thread ids the current one will be identified: <n>.
8155 B<y> [I<n> [I<Vars>]] List lexicals in higher scope <n>. Vars same as B<V>.
8157 B<<> ? List Perl commands to run before each prompt.
8158 B<<> I<expr> Define Perl command to run before each prompt.
8159 B<<<> I<expr> Add to the list of Perl commands to run before each prompt.
8160 B<< *> Delete the list of perl commands to run before each prompt.
8161 B<>> ? List Perl commands to run after each prompt.
8162 B<>> I<expr> Define Perl command to run after each prompt.
8163 B<>>B<>> I<expr> Add to the list of Perl commands to run after each prompt.
8164 B<>>B< *> Delete the list of Perl commands to run after each prompt.
8165 B<{> I<db_command> Define debugger command to run before each prompt.
8166 B<{> ? List debugger commands to run before each prompt.
8167 B<{{> I<db_command> Add to the list of debugger commands to run before each prompt.
8168 B<{ *> Delete the list of debugger commands to run before each prompt.
8169 B<$prc> I<number> Redo a previous command (default previous command).
8170 B<$prc> I<-number> Redo number'th-to-last command.
8171 B<$prc> I<pattern> Redo last command that started with I<pattern>.
8172 See 'B<O> I<recallCommand>' too.
8173 B<$psh$psh> I<cmd> Run cmd in a subprocess (reads from DB::IN, writes to DB::OUT)"
8178 B<$psh> [I<cmd>] Run I<cmd> in subshell (forces \"\$SHELL -c 'cmd'\")."
8180 See 'B<O> I<shellBang>' too.
8181 B<source> I<file> Execute I<file> containing debugger commands (may nest).
8182 B<save> I<file> Save current debugger session (actual history) to I<file>.
8183 B<rerun> Rerun session to current position.
8184 B<rerun> I<n> Rerun session to numbered command.
8185 B<rerun> I<-n> Rerun session to number'th-to-last command.
8186 B<H> I<-number> Display last number commands (default all).
8187 B<H> I<*> Delete complete history.
8188 B<p> I<expr> Same as \"I<print {DB::OUT} expr>\" in current package.
8189 B<|>I<dbcmd> Run debugger command, piping DB::OUT to current pager.
8190 B<||>I<dbcmd> Same as B<|>I<dbcmd> but DB::OUT is temporarily select()ed as well.
8191 B<\=> [I<alias> I<value>] Define a command alias, or list current aliases.
8192 I<command> Execute as a perl statement in current package.
8193 B<R> Poor man's restart of the debugger, some of debugger state
8194 and command-line options may be lost.
8195 Currently the following settings are preserved:
8196 history, breakpoints and actions, debugger B<O>ptions
8197 and the following command-line options: I<-w>, I<-I>, I<-e>.
8199 B<o> [I<opt>] ... Set boolean option to true
8200 B<o> [I<opt>B<?>] Query options
8201 B<o> [I<opt>B<=>I<val>] [I<opt>=B<\">I<val>B<\">] ...
8202 Set options. Use quotes if spaces in value.
8203 I<recallCommand>, I<ShellBang> chars used to recall command or spawn shell;
8204 I<pager> program for output of \"|cmd\";
8205 I<tkRunning> run Tk while prompting (with ReadLine);
8206 I<signalLevel> I<warnLevel> I<dieLevel> level of verbosity;
8207 I<inhibit_exit> Allows stepping off the end of the script.
8208 I<ImmediateStop> Debugger should stop as early as possible.
8209 I<RemotePort> Remote hostname:port for remote debugging
8210 The following options affect what happens with B<V>, B<X>, and B<x> commands:
8211 I<arrayDepth>, I<hashDepth> print only first N elements ('' for all);
8212 I<compactDump>, I<veryCompact> change style of array and hash dump;
8213 I<globPrint> whether to print contents of globs;
8214 I<DumpDBFiles> dump arrays holding debugged files;
8215 I<DumpPackages> dump symbol tables of packages;
8216 I<DumpReused> dump contents of \"reused\" addresses;
8217 I<quote>, I<HighBit>, I<undefPrint> change style of string dump;
8218 I<bareStringify> Do not print the overload-stringified value;
8219 Other options include:
8220 I<PrintRet> affects printing of return value after B<r> command,
8221 I<frame> affects printing messages on subroutine entry/exit.
8222 I<AutoTrace> affects printing messages on possible breaking points.
8223 I<maxTraceLen> gives max length of evals/args listed in stack trace.
8224 I<ornaments> affects screen appearance of the command line.
8225 I<CreateTTY> bits control attempts to create a new TTY on events:
8226 1: on fork() 2: debugger is started inside debugger
8228 During startup options are initialized from \$ENV{PERLDB_OPTS}.
8229 You can put additional initialization options I<TTY>, I<noTTY>,
8230 I<ReadLine>, I<NonStop>, and I<RemotePort> there (or use
8231 B<R> after you set them).
8233 B<q> or B<^D> Quit. Set B<\$DB::finished = 0> to debug global destruction.
8234 B<h> Summary of debugger commands.
8235 B<h> [I<db_command>] Get help [on a specific debugger command], enter B<|h> to page.
8236 B<h h> Long help for debugger commands
8237 B<$doccmd> I<manpage> Runs the external doc viewer B<$doccmd> command on the
8238 named Perl I<manpage>, or on B<$doccmd> itself if omitted.
8239 Set B<\$DB::doccmd> to change viewer.
8241 Type '|h h' for a paged display if this was too hard to read.
8243 "; # Fix balance of vi % matching: }}}}
8245 # note: tabs in the following section are not-so-helpful
8246 $summary = <<"END_SUM";
8247 I<List/search source lines:> I<Control script execution:>
8248 B<l> [I<ln>|I<sub>] List source code B<T> Stack trace
8249 B<-> or B<.> List previous/current line B<s> [I<expr>] Single step [in expr]
8250 B<v> [I<line>] View around line B<n> [I<expr>] Next, steps over subs
8251 B<f> I<filename> View source in file <B<CR>/B<Enter>> Repeat last B<n> or B<s>
8252 B</>I<pattern>B</> B<?>I<patt>B<?> Search forw/backw B<r> Return from subroutine
8253 B<M> Show module versions B<c> [I<ln>|I<sub>] Continue until position
8254 I<Debugger controls:> B<L> List break/watch/actions
8255 B<o> [...] Set debugger options B<t> [I<n>] [I<expr>] Toggle trace [max depth] ][trace expr]
8256 B<<>[B<<>]|B<{>[B<{>]|B<>>[B<>>] [I<cmd>] Do pre/post-prompt B<b> [I<ln>|I<event>|I<sub>] [I<cnd>] Set breakpoint
8257 B<$prc> [I<N>|I<pat>] Redo a previous command B<B> I<ln|*> Delete a/all breakpoints
8258 B<H> [I<-num>] Display last num commands B<a> [I<ln>] I<cmd> Do cmd before line
8259 B<=> [I<a> I<val>] Define/list an alias B<A> I<ln|*> Delete a/all actions
8260 B<h> [I<db_cmd>] Get help on command B<w> I<expr> Add a watch expression
8261 B<h h> Complete help page B<W> I<expr|*> Delete a/all watch exprs
8262 B<|>[B<|>]I<db_cmd> Send output to pager B<$psh>\[B<$psh>\] I<syscmd> Run cmd in a subprocess
8263 B<q> or B<^D> Quit B<R> Attempt a restart
8264 I<Data Examination:> B<expr> Execute perl code, also see: B<s>,B<n>,B<t> I<expr>
8265 B<x>|B<m> I<expr> Evals expr in list context, dumps the result or lists methods.
8266 B<p> I<expr> Print expression (uses script's current package).
8267 B<S> [[B<!>]I<pat>] List subroutine names [not] matching pattern
8268 B<V> [I<Pk> [I<Vars>]] List Variables in Package. Vars can be ~pattern or !pattern.
8269 B<X> [I<Vars>] Same as \"B<V> I<current_package> [I<Vars>]\". B<i> I<class> inheritance tree.
8270 B<y> [I<n> [I<Vars>]] List lexicals in higher scope <n>. Vars same as B<V>.
8271 B<e> Display thread id B<E> Display all thread ids.
8272 For more help, type B<h> I<cmd_letter>, or run B<$doccmd perldebug> for all docs.
8275 # ')}}; # Fix balance of vi % matching
8277 # and this is really numb...
8280 B<s> [I<expr>] Single step [in I<expr>].
8281 B<n> [I<expr>] Next, steps over subroutine calls [in I<expr>].
8282 B<CR>> Repeat last B<n> or B<s> command.
8283 B<r> Return from current subroutine.
8284 B<c> [I<line>|I<sub>] Continue; optionally inserts a one-time-only breakpoint
8285 at the specified position.
8286 B<l> I<min>B<+>I<incr> List I<incr>+1 lines starting at I<min>.
8287 B<l> I<min>B<->I<max> List lines I<min> through I<max>.
8288 B<l> I<line> List single I<line>.
8289 B<l> I<subname> List first window of lines from subroutine.
8290 B<l> I<\$var> List first window of lines from subroutine referenced by I<\$var>.
8291 B<l> List next window of lines.
8292 B<-> List previous window of lines.
8293 B<w> [I<line>] List window around I<line>.
8294 B<.> Return to the executed line.
8295 B<f> I<filename> Switch to viewing I<filename>. File must be already loaded.
8296 I<filename> may be either the full name of the file, or a regular
8297 expression matching the full file name:
8298 B<f> I</home/me/foo.pl> and B<f> I<oo\\.> may access the same file.
8299 Evals (with saved bodies) are considered to be filenames:
8300 B<f> I<(eval 7)> and B<f> I<eval 7\\b> access the body of the 7th eval
8301 (in the order of execution).
8302 B</>I<pattern>B</> Search forwards for I<pattern>; final B</> is optional.
8303 B<?>I<pattern>B<?> Search backwards for I<pattern>; final B<?> is optional.
8304 B<L> List all breakpoints and actions.
8305 B<S> [[B<!>]I<pattern>] List subroutine names [not] matching I<pattern>.
8306 B<t> [I<n>] Toggle trace mode (to max I<n> levels below current stack depth) .
8307 B<t> [I<n>] I<expr> Trace through execution of I<expr>.
8308 B<b> [I<line>] [I<condition>]
8309 Set breakpoint; I<line> defaults to the current execution line;
8310 I<condition> breaks if it evaluates to true, defaults to '1'.
8311 B<b> I<subname> [I<condition>]
8312 Set breakpoint at first line of subroutine.
8313 B<b> I<\$var> Set breakpoint at first line of subroutine referenced by I<\$var>.
8314 B<b> B<load> I<filename> Set breakpoint on 'require'ing the given file.
8315 B<b> B<postpone> I<subname> [I<condition>]
8316 Set breakpoint at first line of subroutine after
8318 B<b> B<compile> I<subname>
8319 Stop after the subroutine is compiled.
8320 B<d> [I<line>] Delete the breakpoint for I<line>.
8321 B<D> Delete all breakpoints.
8322 B<a> [I<line>] I<command>
8323 Set an action to be done before the I<line> is executed;
8324 I<line> defaults to the current execution line.
8325 Sequence is: check for breakpoint/watchpoint, print line
8326 if necessary, do action, prompt user if necessary,
8328 B<a> [I<line>] Delete the action for I<line>.
8329 B<A> Delete all actions.
8330 B<W> I<expr> Add a global watch-expression.
8331 B<W> Delete all watch-expressions.
8332 B<V> [I<pkg> [I<vars>]] List some (default all) variables in package (default current).
8333 Use B<~>I<pattern> and B<!>I<pattern> for positive and negative regexps.
8334 B<X> [I<vars>] Same as \"B<V> I<currentpackage> [I<vars>]\".
8335 B<x> I<expr> Evals expression in list context, dumps the result.
8336 B<m> I<expr> Evals expression in list context, prints methods callable
8337 on the first element of the result.
8338 B<m> I<class> Prints methods callable via the given class.
8340 B<<> ? List Perl commands to run before each prompt.
8341 B<<> I<expr> Define Perl command to run before each prompt.
8342 B<<<> I<expr> Add to the list of Perl commands to run before each prompt.
8343 B<>> ? List Perl commands to run after each prompt.
8344 B<>> I<expr> Define Perl command to run after each prompt.
8345 B<>>B<>> I<expr> Add to the list of Perl commands to run after each prompt.
8346 B<{> I<db_command> Define debugger command to run before each prompt.
8347 B<{> ? List debugger commands to run before each prompt.
8348 B<{{> I<db_command> Add to the list of debugger commands to run before each prompt.
8349 B<$prc> I<number> Redo a previous command (default previous command).
8350 B<$prc> I<-number> Redo number'th-to-last command.
8351 B<$prc> I<pattern> Redo last command that started with I<pattern>.
8352 See 'B<O> I<recallCommand>' too.
8353 B<$psh$psh> I<cmd> Run cmd in a subprocess (reads from DB::IN, writes to DB::OUT)"
8358 B<$psh> [I<cmd>] Run I<cmd> in subshell (forces \"\$SHELL -c 'cmd'\")."
8360 See 'B<O> I<shellBang>' too.
8361 B<source> I<file> Execute I<file> containing debugger commands (may nest).
8362 B<H> I<-number> Display last number commands (default all).
8363 B<p> I<expr> Same as \"I<print {DB::OUT} expr>\" in current package.
8364 B<|>I<dbcmd> Run debugger command, piping DB::OUT to current pager.
8365 B<||>I<dbcmd> Same as B<|>I<dbcmd> but DB::OUT is temporarilly select()ed as well.
8366 B<\=> [I<alias> I<value>] Define a command alias, or list current aliases.
8367 I<command> Execute as a perl statement in current package.
8368 B<v> Show versions of loaded modules.
8369 B<R> Poor man's restart of the debugger, some of debugger state
8370 and command-line options may be lost.
8371 Currently the following settings are preserved:
8372 history, breakpoints and actions, debugger B<O>ptions
8373 and the following command-line options: I<-w>, I<-I>, I<-e>.
8375 B<O> [I<opt>] ... Set boolean option to true
8376 B<O> [I<opt>B<?>] Query options
8377 B<O> [I<opt>B<=>I<val>] [I<opt>=B<\">I<val>B<\">] ...
8378 Set options. Use quotes if spaces in value.
8379 I<recallCommand>, I<ShellBang> chars used to recall command or spawn shell;
8380 I<pager> program for output of \"|cmd\";
8381 I<tkRunning> run Tk while prompting (with ReadLine);
8382 I<signalLevel> I<warnLevel> I<dieLevel> level of verbosity;
8383 I<inhibit_exit> Allows stepping off the end of the script.
8384 I<ImmediateStop> Debugger should stop as early as possible.
8385 I<RemotePort> Remote hostname:port for remote debugging
8386 The following options affect what happens with B<V>, B<X>, and B<x> commands:
8387 I<arrayDepth>, I<hashDepth> print only first N elements ('' for all);
8388 I<compactDump>, I<veryCompact> change style of array and hash dump;
8389 I<globPrint> whether to print contents of globs;
8390 I<DumpDBFiles> dump arrays holding debugged files;
8391 I<DumpPackages> dump symbol tables of packages;
8392 I<DumpReused> dump contents of \"reused\" addresses;
8393 I<quote>, I<HighBit>, I<undefPrint> change style of string dump;
8394 I<bareStringify> Do not print the overload-stringified value;
8395 Other options include:
8396 I<PrintRet> affects printing of return value after B<r> command,
8397 I<frame> affects printing messages on subroutine entry/exit.
8398 I<AutoTrace> affects printing messages on possible breaking points.
8399 I<maxTraceLen> gives max length of evals/args listed in stack trace.
8400 I<ornaments> affects screen appearance of the command line.
8401 I<CreateTTY> bits control attempts to create a new TTY on events:
8402 1: on fork() 2: debugger is started inside debugger
8404 During startup options are initialized from \$ENV{PERLDB_OPTS}.
8405 You can put additional initialization options I<TTY>, I<noTTY>,
8406 I<ReadLine>, I<NonStop>, and I<RemotePort> there (or use
8407 B<R> after you set them).
8409 B<q> or B<^D> Quit. Set B<\$DB::finished = 0> to debug global destruction.
8410 B<h> [I<db_command>] Get help [on a specific debugger command], enter B<|h> to page.
8411 B<h h> Summary of debugger commands.
8412 B<$doccmd> I<manpage> Runs the external doc viewer B<$doccmd> command on the
8413 named Perl I<manpage>, or on B<$doccmd> itself if omitted.
8414 Set B<\$DB::doccmd> to change viewer.
8416 Type '|h' for a paged display if this was too hard to read.
8418 "; # Fix balance of vi % matching: }}}}
8420 # note: tabs in the following section are not-so-helpful
8421 $pre580_summary = <<"END_SUM";
8422 I<List/search source lines:> I<Control script execution:>
8423 B<l> [I<ln>|I<sub>] List source code B<T> Stack trace
8424 B<-> or B<.> List previous/current line B<s> [I<expr>] Single step [in expr]
8425 B<w> [I<line>] List around line B<n> [I<expr>] Next, steps over subs
8426 B<f> I<filename> View source in file <B<CR>/B<Enter>> Repeat last B<n> or B<s>
8427 B</>I<pattern>B</> B<?>I<patt>B<?> Search forw/backw B<r> Return from subroutine
8428 B<v> Show versions of modules B<c> [I<ln>|I<sub>] Continue until position
8429 I<Debugger controls:> B<L> List break/watch/actions
8430 B<O> [...] Set debugger options B<t> [I<expr>] Toggle trace [trace expr]
8431 B<<>[B<<>]|B<{>[B<{>]|B<>>[B<>>] [I<cmd>] Do pre/post-prompt B<b> [I<ln>|I<event>|I<sub>] [I<cnd>] Set breakpoint
8432 B<$prc> [I<N>|I<pat>] Redo a previous command B<d> [I<ln>] or B<D> Delete a/all breakpoints
8433 B<H> [I<-num>] Display last num commands B<a> [I<ln>] I<cmd> Do cmd before line
8434 B<=> [I<a> I<val>] Define/list an alias B<W> I<expr> Add a watch expression
8435 B<h> [I<db_cmd>] Get help on command B<A> or B<W> Delete all actions/watch
8436 B<|>[B<|>]I<db_cmd> Send output to pager B<$psh>\[B<$psh>\] I<syscmd> Run cmd in a subprocess
8437 B<q> or B<^D> Quit B<R> Attempt a restart
8438 I<Data Examination:> B<expr> Execute perl code, also see: B<s>,B<n>,B<t> I<expr>
8439 B<x>|B<m> I<expr> Evals expr in list context, dumps the result or lists methods.
8440 B<p> I<expr> Print expression (uses script's current package).
8441 B<S> [[B<!>]I<pat>] List subroutine names [not] matching pattern
8442 B<V> [I<Pk> [I<Vars>]] List Variables in Package. Vars can be ~pattern or !pattern.
8443 B<X> [I<Vars>] Same as \"B<V> I<current_package> [I<Vars>]\".
8444 B<y> [I<n> [I<Vars>]] List lexicals in higher scope <n>. Vars same as B<V>.
8445 For more help, type B<h> I<cmd_letter>, or run B<$doccmd perldebug> for all docs.
8448 # ')}}; # Fix balance of vi % matching
8450 } ## end sub sethelp
8452 =head2 C<print_help()>
8454 Most of what C<print_help> does is just text formatting. It finds the
8455 C<B> and C<I> ornaments, cleans them off, and substitutes the proper
8456 terminal control characters to simulate them (courtesy of
8457 C<Term::ReadLine::TermCap>).
8462 my $help_str = shift;
8464 # Restore proper alignment destroyed by eeevil I<> and B<>
8465 # ornaments: A pox on both their houses!
8467 # A help command will have everything up to and including
8468 # the first tab sequence padded into a field 16 (or if indented 20)
8469 # wide. If it's wider than that, an extra space will be added.
8471 ^ # only matters at start of line
8472 ( \ {4} | \t )* # some subcommands are indented
8473 ( < ? # so <CR> works
8474 [BI] < [^\t\n] + ) # find an eeevil ornament
8475 ( \t+ ) # original separation, discarded
8476 ( .* ) # this will now start (no earlier) than
8479 my($leadwhite, $command, $midwhite, $text) = ($1, $2, $3, $4);
8480 my $clean = $command;
8481 $clean =~ s/[BI]<([^>]*)>/$1/g;
8483 # replace with this whole string:
8484 ($leadwhite ? " " x 4 : "")
8486 . ((" " x (16 + ($leadwhite ? 4 : 0) - length($clean))) || " ")
8491 $help_str =~ s{ # handle bold ornaments
8492 B < ( [^>] + | > ) >
8494 $Term::ReadLine::TermCap::rl_term_set[2]
8496 . $Term::ReadLine::TermCap::rl_term_set[3]
8499 $help_str =~ s{ # handle italic ornaments
8500 I < ( [^>] + | > ) >
8502 $Term::ReadLine::TermCap::rl_term_set[0]
8504 . $Term::ReadLine::TermCap::rl_term_set[1]
8508 print {$OUT} $help_str;
8511 } ## end sub print_help
8515 This routine does a lot of gyrations to be sure that the pager is C<less>.
8516 It checks for C<less> masquerading as C<more> and records the result in
8517 C<$fixed_less> so we don't have to go through doing the stats again.
8521 use vars qw($fixed_less);
8524 if ($pager =~ /\bless\b/)
8528 elsif ($pager =~ /\bmore\b/)
8530 # Nope, set to more. See what's out there.
8531 my @st_more = stat('/usr/bin/more');
8532 my @st_less = stat('/usr/bin/less');
8534 # is it really less, pretending to be more?
8538 && $st_more[0] == $st_less[0]
8539 && $st_more[1] == $st_less[1]
8549 # We already know if this is set.
8550 return if $fixed_less;
8552 # changes environment!
8553 # 'r' added so we don't do (slow) stats again.
8554 $fixed_less = 1 if _calc_is_less();
8557 } ## end sub fix_less
8559 =head1 DIE AND WARN MANAGEMENT
8563 C<diesignal> is a just-drop-dead C<die> handler. It's most useful when trying
8564 to debug a debugger problem.
8566 It does its best to report the error that occurred, and then forces the
8567 program, debugger, and everything to die.
8573 # No entry/exit messages.
8576 # No return value prints.
8579 # set the abort signal handling to the default (just terminate).
8580 $SIG{'ABRT'} = 'DEFAULT';
8582 # If we enter the signal handler recursively, kill myself with an
8583 # abort signal (so we just terminate).
8584 kill 'ABRT', $$ if $panic++;
8586 # If we can show detailed info, do so.
8587 if ( defined &Carp::longmess ) {
8589 # Don't recursively enter the warn handler, since we're carping.
8590 local $SIG{__WARN__} = '';
8592 # Skip two levels before reporting traceback: we're skipping
8593 # mydie and confess.
8594 local $Carp::CarpLevel = 2; # mydie + confess
8596 # Tell us all about it.
8597 _db_warn( Carp::longmess("Signal @_") );
8600 # No Carp. Tell us about the signal as best we can.
8603 print $DB::OUT "Got signal @_\n";
8608 } ## end sub diesignal
8612 The debugger's own default C<$SIG{__WARN__}> handler. We load C<Carp> to
8613 be able to get a stack trace, and output the warning message vi C<DB::dbwarn()>.
8619 # No entry/exit trace.
8622 # No return value printing.
8625 # Turn off warn and die handling to prevent recursive entries to this
8627 local $SIG{__WARN__} = '';
8628 local $SIG{__DIE__} = '';
8630 # Load Carp if we can. If $^S is false (current thing being compiled isn't
8631 # done yet), we may not be able to do a require.
8632 eval { require Carp }
8633 if defined $^S; # If error/warning during compilation,
8634 # require may be broken.
8636 # Use the core warn() unless Carp loaded OK.
8638 "\nCannot print stack trace, load with -MCarp option to see stack" ),
8640 unless defined &Carp::longmess;
8642 # Save the current values of $single and $trace, and then turn them off.
8643 my ( $mysingle, $mytrace ) = ( $single, $trace );
8647 # We can call Carp::longmess without its being "debugged" (which we
8648 # don't want - we just want to use it!). Capture this for later.
8649 my $mess = Carp::longmess(@_);
8651 # Restore $single and $trace to their original values.
8652 ( $single, $trace ) = ( $mysingle, $mytrace );
8654 # Use the debugger's own special way of printing warnings to print
8655 # the stack trace message.
8661 The debugger's own C<$SIG{__DIE__}> handler. Handles providing a stack trace
8662 by loading C<Carp> and calling C<Carp::longmess()> to get it. We turn off
8663 single stepping and tracing during the call to C<Carp::longmess> to avoid
8664 debugging it - we just want to use it.
8666 If C<dieLevel> is zero, we let the program being debugged handle the
8667 exceptions. If it's 1, you get backtraces for any exception. If it's 2,
8668 the debugger takes over all exception handling, printing a backtrace and
8669 displaying the exception via its C<dbwarn()> routine.
8676 local $SIG{__DIE__} = '';
8677 local $SIG{__WARN__} = '';
8678 if ( $dieLevel > 2 ) {
8679 local $SIG{__WARN__} = \&dbwarn;
8680 _db_warn(@_); # Yell no matter what
8683 if ( $dieLevel < 2 ) {
8684 die @_ if $^S; # in eval propagate
8687 # The code used to check $^S to see if compilation of the current thing
8688 # hadn't finished. We don't do it anymore, figuring eval is pretty stable.
8689 eval { require Carp };
8692 "\nCannot print stack trace, load with -MCarp option to see stack" )
8693 unless defined &Carp::longmess;
8695 # We do not want to debug this chunk (automatic disabling works
8696 # inside DB::DB, but not in Carp). Save $single and $trace, turn them off,
8697 # get the stack trace from Carp::longmess (if possible), restore $signal
8698 # and $trace, and then die with the stack trace.
8699 my ( $mysingle, $mytrace ) = ( $single, $trace );
8705 package Carp; # Do not include us in the list
8706 eval { $mess = Carp::longmess(@_); };
8708 ( $single, $trace ) = ( $mysingle, $mytrace );
8712 =head2 C<warnlevel()>
8714 Set the C<$DB::warnLevel> variable that stores the value of the
8715 C<warnLevel> option. Calling C<warnLevel()> with a positive value
8716 results in the debugger taking over all warning handlers. Setting
8717 C<warnLevel> to zero leaves any warning handlers set up by the program
8718 being debugged in place.
8724 my $prevwarn = $SIG{__WARN__} unless $warnLevel;
8727 $SIG{__WARN__} = \&DB::dbwarn;
8730 $SIG{__WARN__} = $prevwarn;
8732 undef $SIG{__WARN__};
8736 } ## end sub warnLevel
8740 Similar to C<warnLevel>. Non-zero values for C<dieLevel> result in the
8741 C<DB::dbdie()> function overriding any other C<die()> handler. Setting it to
8742 zero lets you use your own C<die()> handler.
8749 my $prevdie = $SIG{__DIE__} unless $dieLevel;
8753 # Always set it to dbdie() for non-zero values.
8754 $SIG{__DIE__} = \&DB::dbdie; # if $dieLevel < 2;
8756 # No longer exists, so don't try to use it.
8757 #$SIG{__DIE__} = \&DB::diehard if $dieLevel >= 2;
8759 # If we've finished initialization, mention that stack dumps
8760 # are enabled, If dieLevel is 1, we won't stack dump if we die
8762 print $OUT "Stack dump during die enabled",
8763 ( $dieLevel == 1 ? " outside of evals" : "" ), ".\n"
8766 # XXX This is probably obsolete, given that diehard() is gone.
8767 print $OUT "Dump printed too.\n" if $dieLevel > 2;
8768 } ## end if ($dieLevel)
8770 # Put the old one back if there was one.
8772 $SIG{__DIE__} = $prevdie;
8773 print $OUT "Default die handler restored.\n";
8775 undef $SIG{__DIE__};
8776 print $OUT "Die handler removed.\n";
8780 } ## end sub dieLevel
8782 =head2 C<signalLevel>
8784 Number three in a series: set C<signalLevel> to zero to keep your own
8785 signal handler for C<SIGSEGV> and/or C<SIGBUS>. Otherwise, the debugger
8786 takes over and handles them with C<DB::diesignal()>.
8792 my $prevsegv = $SIG{SEGV} unless $signalLevel;
8793 my $prevbus = $SIG{BUS} unless $signalLevel;
8794 $signalLevel = shift;
8796 $SIG{SEGV} = \&DB::diesignal;
8797 $SIG{BUS} = \&DB::diesignal;
8800 $SIG{SEGV} = $prevsegv;
8801 $SIG{BUS} = $prevbus;
8805 } ## end sub signalLevel
8807 =head1 SUBROUTINE DECODING SUPPORT
8809 These subroutines are used during the C<x> and C<X> commands to try to
8810 produce as much information as possible about a code reference. They use
8811 L<Devel::Peek> to try to find the glob in which this code reference lives
8812 (if it does) - this allows us to actually code references which correspond
8813 to named subroutines (including those aliased via glob assignment).
8815 =head2 C<CvGV_name()>
8817 Wrapper for C<CvGV_name_or_bust>; tries to get the name of a reference
8818 via that routine. If this fails, return the reference again (when the
8819 reference is stringified, it'll come out as C<SOMETHING(0x...)>).
8825 my $name = CvGV_name_or_bust($in);
8826 defined $name ? $name : $in;
8829 =head2 C<CvGV_name_or_bust> I<coderef>
8831 Calls L<Devel::Peek> to try to find the glob the ref lives in; returns
8832 C<undef> if L<Devel::Peek> can't be loaded, or if C<Devel::Peek::CvGV> can't
8833 find a glob for this ref.
8835 Returns C<< I<package>::I<glob name> >> if the code ref is found in a glob.
8839 use vars qw($skipCvGV);
8841 sub CvGV_name_or_bust {
8843 return if $skipCvGV; # Backdoor to avoid problems if XS broken...
8844 return unless ref $in;
8845 $in = \&$in; # Hard reference...
8846 eval { require Devel::Peek; 1 } or return;
8847 my $gv = Devel::Peek::CvGV($in) or return;
8848 *$gv{PACKAGE} . '::' . *$gv{NAME};
8849 } ## end sub CvGV_name_or_bust
8853 A utility routine used in various places; finds the file where a subroutine
8854 was defined, and returns that filename and a line-number range.
8856 Tries to use C<@sub> first; if it can't find it there, it tries building a
8857 reference to the subroutine and uses C<CvGV_name_or_bust> to locate it,
8858 loading it into C<@sub> as a side effect (XXX I think). If it can't find it
8859 this way, it brute-force searches C<%sub>, checking for identical references.
8863 sub _find_sub_helper {
8866 return unless defined &$subr;
8867 my $name = CvGV_name_or_bust($subr);
8869 $data = $sub{$name} if defined $name;
8870 return $data if defined $data;
8873 $subr = \&$subr; # Hard reference
8876 $s = $_, last if $subr eq \&$_;
8891 return ( $sub{$subr} || _find_sub_helper($subr) );
8892 } ## end sub find_sub
8896 A subroutine that uses the utility function C<methods_via> to find all the
8897 methods in the class corresponding to the current reference and in
8906 # Figure out the class - either this is the class or it's a reference
8907 # to something blessed into that class.
8909 $class = ref $class if ref $class;
8913 # Show the methods that this class has.
8914 methods_via( $class, '', 1 );
8916 # Show the methods that UNIVERSAL has.
8917 methods_via( 'UNIVERSAL', 'UNIVERSAL', 0 );
8918 } ## end sub methods
8920 =head2 C<methods_via($class, $prefix, $crawl_upward)>
8922 C<methods_via> does the work of crawling up the C<@ISA> tree and reporting
8923 all the parent class methods. C<$class> is the name of the next class to
8924 try; C<$prefix> is the message prefix, which gets built up as we go up the
8925 C<@ISA> tree to show parentage; C<$crawl_upward> is 1 if we should try to go
8926 higher in the C<@ISA> tree, 0 if we should stop.
8932 # If we've processed this class already, just quit.
8934 return if $seen{$class}++;
8936 # This is a package that is contributing the methods we're about to print.
8938 my $prepend = $prefix ? "via $prefix: " : '';
8941 # Extract from all the symbols in this class.
8942 my $class_ref = do { no strict "refs"; \%{$class . '::'} };
8943 while (my ($name, $glob) = each %$class_ref) {
8944 # references directly in the symbol table are Proxy Constant
8945 # Subroutines, and are by their very nature defined
8946 # Otherwise, check if the thing is a typeglob, and if it is, it decays
8947 # to a subroutine reference, which can be tested by defined.
8948 # $glob might also be the value -1 (from sub foo;)
8949 # or (say) '$$' (from sub foo ($$);)
8950 # \$glob will be SCALAR in both cases.
8951 if ((ref $glob || ($glob && ref \$glob eq 'GLOB' && defined &$glob))
8952 && !$seen{$name}++) {
8953 push @to_print, "$prepend$name\n";
8960 print $DB::OUT $_ foreach sort @to_print;
8963 # If the $crawl_upward argument is false, just quit here.
8964 return unless shift;
8966 # $crawl_upward true: keep going up the tree.
8967 # Find all the classes this one is a subclass of.
8968 my $class_ISA_ref = do { no strict "refs"; \@{"${class}::ISA"} };
8969 for my $name ( @$class_ISA_ref ) {
8971 # Set up the new prefix.
8972 $prepend = $prefix ? $prefix . " -> $name" : $name;
8974 # Crawl up the tree and keep trying to crawl up.
8975 methods_via( $name, $prepend, 1 );
8977 } ## end sub methods_via
8979 =head2 C<setman> - figure out which command to use to show documentation
8981 Just checks the contents of C<$^O> and sets the C<$doccmd> global accordingly.
8986 $doccmd = $^O !~ /^(?:MSWin32|VMS|os2|amigaos|riscos)\z/s
8987 ? "man" # O Happy Day!
8988 : "perldoc"; # Alas, poor unfortunates
8991 =head2 C<runman> - run the appropriate command to show documentation
8993 Accepts a man page name; runs the appropriate command to display it (set up
8994 during debugger initialization). Uses C<_db_system()> to avoid mucking up the
8995 program's STDIN and STDOUT.
9002 _db_system("$doccmd $doccmd");
9006 # this way user can override, like with $doccmd="man -Mwhatever"
9007 # or even just "man " to disable the path check.
9008 if ( $doccmd ne 'man' ) {
9009 _db_system("$doccmd $page");
9013 $page = 'perl' if lc($page) eq 'help';
9016 my $man1dir = $Config::Config{man1direxp};
9017 my $man3dir = $Config::Config{man3direxp};
9018 for ( $man1dir, $man3dir ) { s#/[^/]*\z## if /\S/ }
9020 $manpath .= "$man1dir:" if $man1dir =~ /\S/;
9021 $manpath .= "$man3dir:" if $man3dir =~ /\S/ && $man1dir ne $man3dir;
9022 chop $manpath if $manpath;
9024 # harmless if missing, I figure
9025 local $ENV{MANPATH} = $manpath if $manpath;
9026 my $nopathopt = $^O =~ /dunno what goes here/;
9031 # I just *know* there are men without -M
9032 ( ( $manpath && !$nopathopt ) ? ( "-M", $manpath ) : () ),
9037 unless ( $page =~ /^perl\w/ ) {
9038 # Previously the debugger contained a list which it slurped in,
9039 # listing the known "perl" manpages. However, it was out of date,
9040 # with errors both of omission and inclusion. This approach is
9041 # considerably less complex. The failure mode on a butchered
9042 # install is simply that the user has to run man or perldoc
9043 # "manually" with the full manpage name.
9045 # There is a list of $^O values in installperl to determine whether
9046 # the directory is 'pods' or 'pod'. However, we can avoid tight
9047 # coupling to that by simply checking the "non-standard" 'pods'
9049 my $pods = "$Config::Config{privlibexp}/pods";
9050 $pods = "$Config::Config{privlibexp}/pod"
9052 if (-f "$pods/perl$page.pod") {
9053 CORE::system( $doccmd,
9054 ( ( $manpath && !$nopathopt ) ? ( "-M", $manpath ) : () ),
9058 } ## end if (CORE::system($doccmd...
9061 #use Carp; # This did break, left for debugging
9063 =head1 DEBUGGER INITIALIZATION - THE SECOND BEGIN BLOCK
9065 Because of the way the debugger interface to the Perl core is designed, any
9066 debugger package globals that C<DB::sub()> requires have to be defined before
9067 any subroutines can be called. These are defined in the second C<BEGIN> block.
9069 This block sets things up so that (basically) the world is sane
9070 before the debugger starts executing. We set up various variables that the
9071 debugger has to have set up before the Perl core starts running:
9077 The debugger's own filehandles (copies of STD and STDOUT for now).
9081 Characters for shell escapes, the recall command, and the history command.
9085 The maximum recursion depth.
9089 The size of a C<w> command's window.
9093 The before-this-line context to be printed in a C<v> (view a window around this line) command.
9097 The fact that we're not in a sub at all right now.
9101 The default SIGINT handler for the debugger.
9105 The appropriate value of the flag in C<$^D> that says the debugger is running
9109 The current debugger recursion level
9113 The list of postponed items and the C<$single> stack (XXX define this)
9117 That we want no return values and no subroutine entry/exit trace.
9123 # The following BEGIN is very handy if debugger goes havoc, debugging debugger?
9125 use vars qw($db_stop);
9127 BEGIN { # This does not compile, alas. (XXX eh?)
9128 $IN = \*STDIN; # For bugs before DB::OUT has been opened
9129 $OUT = \*STDERR; # For errors before DB::OUT has been opened
9131 # Define characters used by command parsing.
9132 $sh = '!'; # Shell escape (does not work)
9133 $rc = ','; # Recall command (does not work)
9134 @hist = ('?'); # Show history (does not work)
9135 @truehist = (); # Can be saved for replay (per session)
9137 # This defines the point at which you get the 'deep recursion'
9138 # warning. It MUST be defined or the debugger will not load.
9141 # Number of lines around the current one that are shown in the
9145 # How much before-the-current-line context the 'v' command should
9146 # use in calculating the start of the window it will display.
9149 # We're not in any sub yet, but we need this to be a defined value.
9152 # Set up the debugger's interrupt handler. It simply sets a flag
9153 # ($signal) that DB::DB() will check before each command is executed.
9154 $SIG{INT} = \&DB::catch;
9156 # The following lines supposedly, if uncommented, allow the debugger to
9157 # debug itself. Perhaps we can try that someday.
9158 # This may be enabled to debug debugger:
9159 #$warnLevel = 1 unless defined $warnLevel;
9160 #$dieLevel = 1 unless defined $dieLevel;
9161 #$signalLevel = 1 unless defined $signalLevel;
9163 # This is the flag that says "a debugger is running, please call
9164 # DB::DB and DB::sub". We will turn it on forcibly before we try to
9165 # execute anything in the user's context, because we always want to
9167 $db_stop = 0; # Compiler warning ...
9168 $db_stop = 1 << 30; # ... because this is only used in an eval() later.
9170 # This variable records how many levels we're nested in debugging.
9171 # Used in the debugger prompt, and in determining whether it's all over or
9173 $level = 0; # Level of recursive debugging
9175 # "Triggers bug (?) in perl if we postpone this until runtime."
9176 # XXX No details on this yet, or whether we should fix the bug instead
9177 # of work around it. Stay tuned.
9180 # Used to track the current stack depth using the auto-stacked-variable
9182 $stack_depth = 0; # Localized repeatedly; simple way to track $#stack
9184 # Don't print return values on exiting a subroutine.
9187 # No extry/exit tracing.
9192 BEGIN { $^W = $ini_warn; } # Switch warnings back
9194 =head1 READLINE SUPPORT - COMPLETION FUNCTION
9198 C<readline> support - adds command completion to basic C<readline>.
9200 Returns a list of possible completions to C<readline> when invoked. C<readline>
9201 will print the longest common substring following the text already entered.
9203 If there is only a single possible completion, C<readline> will use it in full.
9205 This code uses C<map> and C<grep> heavily to create lists of possible
9206 completion. Think LISP in this section.
9212 # Specific code for b c l V m f O, &blah, $blah, @blah, %blah
9213 # $text is the text to be completed.
9214 # $line is the incoming line typed by the user.
9215 # $start is the start of the text to be completed in the incoming line.
9216 my ( $text, $line, $start ) = @_;
9218 # Save the initial text.
9219 # The search pattern is current package, ::, extract the next qualifier
9220 # Prefix and pack are set to undef.
9221 my ( $itext, $search, $prefix, $pack ) =
9222 ( $text, "^\Q${package}::\E([^:]+)\$" );
9224 =head3 C<b postpone|compile>
9230 Find all the subroutines that might match in this package
9234 Add C<postpone>, C<load>, and C<compile> as possibles (we may be completing the keyword itself)
9238 Include all the rest of the subs that are known
9242 C<grep> out the ones that match the text we have so far
9246 Return this as the list of possible completions
9252 return sort grep /^\Q$text/, ( keys %sub ),
9253 qw(postpone load compile), # subroutines
9254 ( map { /$search/ ? ($1) : () } keys %sub )
9255 if ( substr $line, 0, $start ) =~ /^\|*[blc]\s+((postpone|compile)\s+)?$/;
9259 Get all the possible files from C<@INC> as it currently stands and
9260 select the ones that match the text so far.
9264 return sort grep /^\Q$text/, values %INC # files
9265 if ( substr $line, 0, $start ) =~ /^\|*b\s+load\s+$/;
9267 =head3 C<V> (list variable) and C<m> (list modules)
9269 There are two entry points for these commands:
9271 =head4 Unqualified package names
9273 Get the top-level packages and grab everything that matches the text
9274 so far. For each match, recursively complete the partial packages to
9275 get all possible matching packages. Return this sorted list.
9279 return sort map { ( $_, db_complete( $_ . "::", "V ", 2 ) ) }
9280 grep /^\Q$text/, map { /^(.*)::$/ ? ($1) : () } keys %:: # top-packages
9281 if ( substr $line, 0, $start ) =~ /^\|*[Vm]\s+$/ and $text =~ /^\w*$/;
9283 =head4 Qualified package names
9285 Take a partially-qualified package and find all subpackages for it
9286 by getting all the subpackages for the package so far, matching all
9287 the subpackages against the text, and discarding all of them which
9288 start with 'main::'. Return this list.
9292 return sort map { ( $_, db_complete( $_ . "::", "V ", 2 ) ) }
9293 grep !/^main::/, grep /^\Q$text/,
9294 map { /^(.*)::$/ ? ( $prefix . "::$1" ) : () }
9295 do { no strict 'refs'; keys %{ $prefix . '::' } }
9296 if ( substr $line, 0, $start ) =~ /^\|*[Vm]\s+$/
9297 and $text =~ /^(.*[^:])::?(\w*)$/
9300 =head3 C<f> - switch files
9302 Here, we want to get a fully-qualified filename for the C<f> command.
9307 =item 1. The original source file itself
9309 =item 2. A file from C<@INC>
9311 =item 3. An C<eval> (the debugger gets a C<(eval N)> fake file for each C<eval>).
9317 if ( $line =~ /^\|*f\s+(.*)/ ) { # Loaded files
9318 # We might possibly want to switch to an eval (which has a "filename"
9319 # like '(eval 9)'), so we may need to clean up the completion text
9320 # before proceeding.
9321 $prefix = length($1) - length($text);
9326 Under the debugger, source files are represented as C<_E<lt>/fullpath/to/file>
9327 (C<eval>s are C<_E<lt>(eval NNN)>) keys in C<%main::>. We pull all of these
9328 out of C<%main::>, add the initial source file, and extract the ones that
9329 match the completion text so far.
9334 map { substr $_, 2 + $prefix } grep /^_<\Q$text/, ( keys %main:: ),
9336 } ## end if ($line =~ /^\|*f\s+(.*)/)
9338 =head3 Subroutine name completion
9340 We look through all of the defined subs (the keys of C<%sub>) and
9341 return both all the possible matches to the subroutine name plus
9342 all the matches qualified to the current package.
9346 if ( ( substr $text, 0, 1 ) eq '&' ) { # subroutines
9347 $text = substr $text, 1;
9349 return sort map "$prefix$_", grep /^\Q$text/, ( keys %sub ),
9351 map { /$search/ ? ($1) : () }
9354 } ## end if ((substr $text, 0, ...
9356 =head3 Scalar, array, and hash completion: partially qualified package
9358 Much like the above, except we have to do a little more cleanup:
9362 if ( $text =~ /^[\$@%](.*)::(.*)/ ) { # symbols in a package
9370 Determine the package that the symbol is in. Put it in C<::> (effectively C<main::>) if no package is specified.
9374 $pack = ( $1 eq 'main' ? '' : $1 ) . '::';
9380 Figure out the prefix vs. what needs completing.
9384 $prefix = ( substr $text, 0, 1 ) . $1 . '::';
9391 Look through all the symbols in the package. C<grep> out all the possible hashes/arrays/scalars, and then C<grep> the possible matches out of those. C<map> the prefix onto all the possibilities.
9397 map "$prefix$_", grep /^\Q$text/, grep /^_?[a-zA-Z]/,
9405 If there's only one hit, and it's a package qualifier, and it's not equal to the initial text, re-complete it using the symbol we actually found.
9409 if ( @out == 1 and $out[0] =~ /::$/ and $out[0] ne $itext ) {
9410 return db_complete( $out[0], $line, $start );
9413 # Return the list of possibles.
9416 } ## end if ($text =~ /^[\$@%](.*)::(.*)/)
9422 =head3 Symbol completion: current package or package C<main>.
9426 if ( $text =~ /^[\$@%]/ ) { # symbols (in $package + packages in main)
9433 If it's C<main>, delete main to just get C<::> leading.
9437 $pack = ( $package eq 'main' ? '' : $package ) . '::';
9443 We set the prefix to the item's sigil, and trim off the sigil to get the text to be completed.
9447 $prefix = substr $text, 0, 1;
9448 $text = substr $text, 1;
9456 We look for the lexical scope above DB::DB and auto-complete lexical variables
9457 if PadWalker could be loaded.
9461 if (not $text =~ /::/ and eval {
9463 pop @INC if $INC[-1] eq '.';
9464 require PadWalker } ) {
9467 my @info = caller($level);
9471 last if $info[3] eq 'DB::DB';
9474 my $lexicals = PadWalker::peek_my($level);
9475 push @out, grep /^\Q$prefix$text/, keys %$lexicals;
9483 If the package is C<::> (C<main>), create an empty list; if it's something else, create a list of all the packages known. Append whichever list to a list of all the possible symbols in the current package. C<grep> out the matches to the text entered so far, then C<map> the prefix back onto the symbols.
9487 push @out, map "$prefix$_", grep /^\Q$text/,
9488 ( grep /^_?[a-zA-Z]/, do { no strict 'refs'; keys %$pack } ),
9489 ( $pack eq '::' ? () : ( grep /::$/, keys %:: ) );
9493 If there's only one hit, it's a package qualifier, and it's not equal to the initial text, recomplete using this symbol.
9499 if ( @out == 1 and $out[0] =~ /::$/ and $out[0] ne $itext ) {
9500 return db_complete( $out[0], $line, $start );
9503 # Return the list of possibles.
9505 } ## end if ($text =~ /^[\$@%]/)
9509 We use C<option_val()> to look up the current value of the option. If there's
9510 only a single value, we complete the command in such a way that it is a
9511 complete command for setting the option in question. If there are multiple
9512 possible values, we generate a command consisting of the option plus a trailing
9513 question mark, which, if executed, will list the current value of the option.
9517 if ( ( substr $line, 0, $start ) =~ /^\|*[oO]\b.*\s$/ )
9518 { # Options after space
9519 # We look for the text to be matched in the list of possible options,
9520 # and fetch the current value.
9521 my @out = grep /^\Q$text/, @options;
9522 my $val = option_val( $out[0], undef );
9524 # Set up a 'query option's value' command.
9526 if ( not defined $val or $val =~ /[\n\r]/ ) {
9528 # There's really nothing else we can do.
9531 # We have a value. Create a proper option-setting command.
9532 elsif ( $val =~ /\s/ ) {
9534 # XXX This may be an extraneous variable.
9537 # We'll want to quote the string (because of the embedded
9538 # whtespace), but we want to make sure we don't end up with
9539 # mismatched quote characters. We try several possibilities.
9540 foreach my $l ( split //, qq/\"\'\#\|/ ) {
9542 # If we didn't find this quote character in the value,
9543 # quote it using this quote character.
9544 $out = "$l$val$l ", last if ( index $val, $l ) == -1;
9546 } ## end elsif ($val =~ /\s/)
9548 # Don't need any quotes.
9553 # If there were multiple possible values, return '? ', which
9554 # makes the command into a query command. If there was just one,
9555 # have readline append that.
9556 $rl_attribs->{completer_terminator_character} =
9557 ( @out == 1 ? $out : '? ' );
9559 # Return list of possibilities.
9561 } ## end if ((substr $line, 0, ...
9563 =head3 Filename completion
9565 For entering filenames. We simply call C<readline>'s C<filename_list()>
9566 method with the completion text to get the possible completions.
9570 return $term->filename_list($text); # filenames
9572 } ## end sub db_complete
9574 =head1 MISCELLANEOUS SUPPORT FUNCTIONS
9576 Functions that possibly ought to be somewhere else.
9586 print $OUT "Use 'q' to quit or 'R' to restart. 'h q' for details.\n";
9591 If we have $ini_pids, save it in the environment; else remove it from the
9592 environment. Used by the C<R> (restart) command.
9597 if ( defined($ini_pids) ) {
9598 $ENV{PERLDB_PIDS} = $ini_pids;
9601 delete( $ENV{PERLDB_PIDS} );
9603 } ## end sub clean_ENV
9605 # PERLDBf_... flag names from perl.h
9606 our ( %DollarCaretP_flags, %DollarCaretP_flags_r );
9609 %DollarCaretP_flags = (
9610 PERLDBf_SUB => 0x01, # Debug sub enter/exit
9611 PERLDBf_LINE => 0x02, # Keep line #
9612 PERLDBf_NOOPT => 0x04, # Switch off optimizations
9613 PERLDBf_INTER => 0x08, # Preserve more data
9614 PERLDBf_SUBLINE => 0x10, # Keep subr source lines
9615 PERLDBf_SINGLE => 0x20, # Start with single-step on
9616 PERLDBf_NONAME => 0x40, # For _SUB: no name of the subr
9617 PERLDBf_GOTO => 0x80, # Report goto: call DB::goto
9618 PERLDBf_NAMEEVAL => 0x100, # Informative names for evals
9619 PERLDBf_NAMEANON => 0x200, # Informative names for anon subs
9620 PERLDBf_SAVESRC => 0x400, # Save source lines into @{"_<$filename"}
9621 PERLDB_ALL => 0x33f, # No _NONAME, _GOTO
9623 # PERLDBf_LINE also enables the actions of PERLDBf_SAVESRC, so the debugger
9624 # doesn't need to set it. It's provided for the benefit of profilers and
9625 # other code analysers.
9627 %DollarCaretP_flags_r = reverse %DollarCaretP_flags;
9630 sub parse_DollarCaretP_flags {
9635 foreach my $f ( split /\s*\|\s*/, $flags ) {
9637 if ( $f =~ /^0x([[:xdigit:]]+)$/ ) {
9640 elsif ( $f =~ /^(\d+)$/ ) {
9643 elsif ( $f =~ /^DEFAULT$/i ) {
9644 $value = $DollarCaretP_flags{PERLDB_ALL};
9647 $f =~ /^(?:PERLDBf_)?(.*)$/i;
9648 $value = $DollarCaretP_flags{ 'PERLDBf_' . uc($1) };
9649 unless ( defined $value ) {
9651 "Unrecognized \$^P flag '$f'!\n",
9652 "Acceptable flags are: "
9653 . join( ', ', sort keys %DollarCaretP_flags ),
9654 ", and hexadecimal and decimal numbers.\n"
9664 sub expand_DollarCaretP_flags {
9665 my $DollarCaretP = shift;
9668 my $n = ( 1 << $_ );
9669 ( $DollarCaretP & $n )
9670 ? ( $DollarCaretP_flags_r{$n}
9671 || sprintf( '0x%x', $n ) )
9675 return @bits ? join( '|', @bits ) : 0;
9682 Rerun the current session to:
9684 rerun current position
9686 rerun 4 command number 4
9688 rerun -4 current command minus 4 (go back 4 steps)
9690 Whether this always makes sense, in the current context is unknowable, and is
9691 in part left as a useful exercise for the reader. This sub returns the
9692 appropriate arguments to rerun the current session.
9699 pop(@truehist); # strim
9700 unless (defined $truehist[$i]) {
9701 print "Unable to return to non-existent command: $i\n";
9703 $#truehist = ($i < 0 ? $#truehist + $i : $i > 0 ? $i : $#truehist);
9704 my @temp = @truehist; # store
9705 push(@DB::typeahead, @truehist); # saved
9706 @truehist = @hist = (); # flush
9707 @args = restart(); # setup
9708 get_list("PERLDB_HIST"); # clean
9709 set_list("PERLDB_HIST", @temp); # reset
9716 Restarting the debugger is a complex operation that occurs in several phases.
9717 First, we try to reconstruct the command line that was used to invoke Perl
9723 # I may not be able to resurrect you, but here goes ...
9725 "Warning: some settings and command-line options may be lost!\n";
9726 my ( @script, @flags, $cl );
9728 # If warn was on before, turn it on again.
9729 push @flags, '-w' if $ini_warn;
9731 # Rebuild the -I flags that were on the initial
9734 push @flags, '-I', $_;
9737 # Turn on taint if it was on before.
9738 push @flags, '-T' if ${^TAINT};
9740 # Arrange for setting the old INC:
9741 # Save the current @init_INC in the environment.
9742 set_list( "PERLDB_INC", @ini_INC );
9744 # If this was a perl one-liner, go to the "file"
9745 # corresponding to the one-liner read all the lines
9746 # out of it (except for the first one, which is going
9747 # to be added back on again when 'perl -d' runs: that's
9748 # the 'require perl5db.pl;' line), and add them back on
9749 # to the command line to be executed.
9751 my $lines = *{$main::{'_<-e'}}{ARRAY};
9752 for ( 1 .. $#$lines ) { # The first line is PERL5DB
9753 chomp( $cl = $lines->[$_] );
9754 push @script, '-e', $cl;
9756 } ## end if ($0 eq '-e')
9758 # Otherwise we just reuse the original name we had
9766 After the command line has been reconstructed, the next step is to save
9767 the debugger's status in environment variables. The C<DB::set_list> routine
9768 is used to save aggregate variables (both hashes and arrays); scalars are
9769 just popped into environment variables directly.
9773 # If the terminal supported history, grab it and
9774 # save that in the environment.
9775 set_list( "PERLDB_HIST",
9776 $term->Features->{getHistory}
9780 # Find all the files that were visited during this
9781 # session (i.e., the debugger had magic hashes
9782 # corresponding to them) and stick them in the environment.
9783 my @had_breakpoints = keys %had_breakpoints;
9784 set_list( "PERLDB_VISITED", @had_breakpoints );
9786 # Save the debugger options we chose.
9787 set_list( "PERLDB_OPT", %option );
9788 # set_list( "PERLDB_OPT", options2remember() );
9790 # Save the break-on-loads.
9791 set_list( "PERLDB_ON_LOAD", %break_on_load );
9795 The most complex part of this is the saving of all of the breakpoints. They
9796 can live in an awful lot of places, and we have to go through all of them,
9797 find the breakpoints, and then save them in the appropriate environment
9798 variable via C<DB::set_list>.
9802 # Go through all the breakpoints and make sure they're
9805 for ( 0 .. $#had_breakpoints ) {
9807 # We were in this file.
9808 my $file = $had_breakpoints[$_];
9810 # Grab that file's magic line hash.
9811 *dbline = $main::{ '_<' . $file };
9813 # Skip out if it doesn't exist, or if the breakpoint
9814 # is in a postponed file (we'll do postponed ones
9816 next unless %dbline or $postponed_file{$file};
9818 # In an eval. This is a little harder, so we'll
9819 # do more processing on that below.
9820 ( push @hard, $file ), next
9821 if $file =~ /^\(\w*eval/;
9823 # XXX I have no idea what this is doing. Yet.
9825 @add = %{ $postponed_file{$file} }
9826 if $postponed_file{$file};
9828 # Save the list of all the breakpoints for this file.
9829 set_list( "PERLDB_FILE_$_", %dbline, @add );
9831 # Serialize the extra data %breakpoints_data hash.
9833 set_list( "PERLDB_FILE_ENABLED_$_",
9834 map { _is_breakpoint_enabled($file, $_) ? 1 : 0 }
9835 sort { $a <=> $b } keys(%dbline)
9837 } ## end for (0 .. $#had_breakpoints)
9839 # The breakpoint was inside an eval. This is a little
9840 # more difficult. XXX and I don't understand it.
9841 foreach my $hard_file (@hard) {
9842 # Get over to the eval in question.
9843 *dbline = $main::{ '_<' . $hard_file };
9844 my $quoted = quotemeta $hard_file;
9846 for my $sub ( keys %sub ) {
9847 if (my ($n1, $n2) = $sub{$sub} =~ /\A$quoted:(\d+)-(\d+)\z/) {
9848 $subs{$sub} = [ $n1, $n2 ];
9853 "No subroutines in $hard_file, ignoring breakpoints.\n";
9856 LINES: foreach my $line ( keys %dbline ) {
9858 # One breakpoint per sub only:
9859 my ( $offset, $found );
9860 SUBS: foreach my $sub ( keys %subs ) {
9862 $subs{$sub}->[1] >= $line # Not after the subroutine
9864 not defined $offset # Not caught
9870 $offset = $line - $subs{$sub}->[0];
9872 $offset = "+$offset";
9875 } ## end if ($subs{$sub}->[1] >=...
9876 } ## end for $sub (keys %subs)
9877 if ( defined $offset ) {
9878 $postponed{$found} =
9879 "break $offset if $dbline{$line}";
9883 ("Breakpoint in ${hard_file}:$line ignored:"
9884 . " after all the subroutines.\n");
9886 } ## end for $line (keys %dbline)
9887 } ## end for (@hard)
9889 # Save the other things that don't need to be
9891 set_list( "PERLDB_POSTPONE", %postponed );
9892 set_list( "PERLDB_PRETYPE", @$pretype );
9893 set_list( "PERLDB_PRE", @$pre );
9894 set_list( "PERLDB_POST", @$post );
9895 set_list( "PERLDB_TYPEAHEAD", @typeahead );
9897 # We are officially restarting.
9898 $ENV{PERLDB_RESTART} = 1;
9900 # We are junking all child debuggers.
9901 delete $ENV{PERLDB_PIDS}; # Restore ini state
9903 # Set this back to the initial pid.
9904 $ENV{PERLDB_PIDS} = $ini_pids if defined $ini_pids;
9908 After all the debugger status has been saved, we take the command we built up
9909 and then return it, so we can C<exec()> it. The debugger will spot the
9910 C<PERLDB_RESTART> environment variable and realize it needs to reload its state
9911 from the environment.
9915 # And run Perl again. Add the "-d" flag, all the
9916 # flags we built up, the script (whether a one-liner
9917 # or a file), add on the -emacs flag for a client editor,
9918 # and then the old arguments.
9920 return ($^X, '-d', @flags, @script, ($client_editor ? '-emacs' : ()), @ARGS);
9926 =head1 END PROCESSING - THE C<END> BLOCK
9928 Come here at the very end of processing. We want to go into a
9929 loop where we allow the user to enter commands and interact with the
9930 debugger, but we don't want anything else to execute.
9932 First we set the C<$finished> variable, so that some commands that
9933 shouldn't be run after the end of program quit working.
9935 We then figure out whether we're truly done (as in the user entered a C<q>
9936 command, or we finished execution while running nonstop). If we aren't,
9937 we set C<$single> to 1 (causing the debugger to get control again).
9939 We then call C<DB::fake::at_exit()>, which returns the C<Use 'q' to quit ...>
9940 message and returns control to the debugger. Repeat.
9942 When the user finally enters a C<q> command, C<$fall_off_end> is set to
9943 1 and the C<END> block simply exits with C<$single> set to 0 (don't
9944 break, run to completion.).
9949 $finished = 1 if $inhibit_exit; # So that some commands may be disabled.
9950 $fall_off_end = 1 unless $inhibit_exit;
9952 # Do not stop in at_exit() and destructors on exit:
9953 if ($fall_off_end or $runnonstop) {
9957 DB::fake::at_exit();
9961 =head1 PRE-5.8 COMMANDS
9963 Some of the commands changed function quite a bit in the 5.8 command
9964 realignment, so much so that the old code had to be replaced completely.
9965 Because we wanted to retain the option of being able to go back to the
9966 former command set, we moved the old code off to this section.
9968 There's an awful lot of duplicated code here. We've duplicated the
9969 comments to keep things clear.
9973 Does nothing. Used to I<turn off> commands.
9977 sub cmd_pre580_null {
9982 =head2 Old C<a> command.
9984 This version added actions if you supplied them, and deleted them
9993 # Argument supplied. Add the action.
9994 if ( $cmd =~ /^(\d*)\s*(.*)/ ) {
9996 # If the line isn't there, use the current line.
9997 my $i = $1 || $line;
10000 # If there is an action ...
10003 # ... but the line isn't breakable, skip it.
10004 if ( $dbline[$i] == 0 ) {
10005 print $OUT "Line $i may not have an action.\n";
10009 # ... and the line is breakable:
10010 # Mark that there's an action in this file.
10011 $had_breakpoints{$filename} |= 2;
10013 # Delete any current action.
10014 $dbline{$i} =~ s/\0[^\0]*//;
10016 # Add the new action, continuing the line as needed.
10017 $dbline{$i} .= "\0" . action($j);
10019 } ## end if (length $j)
10021 # No action supplied.
10024 # Delete the action.
10025 $dbline{$i} =~ s/\0[^\0]*//;
10027 # Mark as having no break or action if nothing's left.
10028 delete $dbline{$i} if $dbline{$i} eq '';
10030 } ## end if ($cmd =~ /^(\d*)\s*(.*)/)
10031 } ## end sub cmd_pre580_a
10033 =head2 Old C<b> command
10042 my $dbline = shift;
10045 if ( $cmd =~ /^load\b\s*(.*)/ ) {
10051 # b compile|postpone <some sub> [<condition>]
10052 # The interpreter actually traps this one for us; we just put the
10053 # necessary condition in the %postponed hash.
10054 elsif ( $cmd =~ /^(postpone|compile)\b\s*([':A-Za-z_][':\w]*)\s*(.*)/ ) {
10056 # Capture the condition if there is one. Make it true if none.
10057 my $cond = length $3 ? $3 : '1';
10059 # Save the sub name and set $break to 1 if $1 was 'postpone', 0
10060 # if it was 'compile'.
10061 my ( $subname, $break ) = ( $2, $1 eq 'postpone' );
10063 # De-Perl4-ify the name - ' separators to ::.
10064 $subname =~ s/\'/::/g;
10066 # Qualify it into the current package unless it's already qualified.
10067 $subname = "${package}::" . $subname
10068 unless $subname =~ /::/;
10070 # Add main if it starts with ::.
10071 $subname = "main" . $subname if substr( $subname, 0, 2 ) eq "::";
10073 # Save the break type for this sub.
10074 $postponed{$subname} = $break ? "break +0 if $cond" : "compile";
10075 } ## end elsif ($cmd =~ ...
10077 # b <sub name> [<condition>]
10078 elsif ( $cmd =~ /^([':A-Za-z_][':\w]*(?:\[.*\])?)\s*(.*)/ ) {
10080 my $cond = length $2 ? $2 : '1';
10081 cmd_b_sub( $subname, $cond );
10083 # b <line> [<condition>].
10084 elsif ( $cmd =~ /^(\d*)\s*(.*)/ ) {
10085 my $i = $1 || $dbline;
10086 my $cond = length $2 ? $2 : '1';
10087 cmd_b_line( $i, $cond );
10089 } ## end sub cmd_pre580_b
10091 =head2 Old C<D> command.
10093 Delete all breakpoints unconditionally.
10100 if ( $cmd =~ /^\s*$/ ) {
10101 print $OUT "Deleting all breakpoints...\n";
10103 # %had_breakpoints lists every file that had at least one
10104 # breakpoint in it.
10106 for $file ( keys %had_breakpoints ) {
10108 # Switch to the desired file temporarily.
10109 local *dbline = $main::{ '_<' . $file };
10114 # For all lines in this file ...
10115 for my $i (1 .. $max) {
10117 # If there's a breakpoint or action on this line ...
10118 if ( defined $dbline{$i} ) {
10120 # ... remove the breakpoint.
10121 $dbline{$i} =~ s/^[^\0]+//;
10122 if ( $dbline{$i} =~ s/^\0?$// ) {
10124 # Remove the entry altogether if no action is there.
10125 delete $dbline{$i};
10127 } ## end if (defined $dbline{$i...
10128 } ## end for my $i (1 .. $max)
10130 # If, after we turn off the "there were breakpoints in this file"
10131 # bit, the entry in %had_breakpoints for this file is zero,
10132 # we should remove this file from the hash.
10133 if ( not $had_breakpoints{$file} &= ~1 ) {
10134 delete $had_breakpoints{$file};
10136 } ## end for $file (keys %had_breakpoints)
10138 # Kill off all the other breakpoints that are waiting for files that
10139 # haven't been loaded yet.
10141 undef %postponed_file;
10142 undef %break_on_load;
10143 } ## end if ($cmd =~ /^\s*$/)
10144 } ## end sub cmd_pre580_D
10146 =head2 Old C<h> command
10148 Print help. Defaults to printing the long-form help; the 5.8 version
10149 prints the summary by default.
10157 # Print the *right* help, long format.
10158 if ( $cmd =~ /^\s*$/ ) {
10159 print_help($pre580_help);
10162 # 'h h' - explicitly-requested summary.
10163 elsif ( $cmd =~ /^h\s*/ ) {
10164 print_help($pre580_summary);
10167 # Find and print a command's help.
10168 elsif ( $cmd =~ /^h\s+(\S.*)$/ ) {
10169 my $asked = $1; # for proper errmsg
10170 my $qasked = quotemeta($asked); # for searching
10171 # XXX: finds CR but not <CR>
10175 (?:[IB]<) # Optional markup
10176 $qasked # The command name
10183 ( # The command help:
10185 (?:[IB]<) # Optional markup
10186 $qasked # The command name
10187 ([\s\S]*?) # Lines starting with tabs
10191 ) # Line not starting with space
10192 # (Next command's help)
10196 } ## end if ($pre580_help =~ /^<?(?:[IB]<)$qasked/m)
10200 print_help("B<$asked> is not a debugger command.\n");
10202 } ## end elsif ($cmd =~ /^h\s+(\S.*)$/)
10203 } ## end sub cmd_pre580_h
10205 =head2 Old C<W> command
10207 C<W E<lt>exprE<gt>> adds a watch expression, C<W> deletes them all.
10215 # Delete all watch expressions.
10216 if ( $cmd =~ /^$/ ) {
10218 # No watching is going on.
10221 # Kill all the watch expressions and values.
10222 @to_watch = @old_watch = ();
10225 # Add a watch expression.
10226 elsif ( $cmd =~ /^(.*)/s ) {
10228 # add it to the list to be watched.
10229 push @to_watch, $1;
10231 # Get the current value of the expression.
10232 # Doesn't handle expressions returning list values!
10234 # The &-call is here to ascertain the mutability of @_.
10235 my ($val) = &DB::eval;
10236 $val = ( defined $val ) ? "'$val'" : 'undef';
10239 push @old_watch, $val;
10241 # We're watching stuff.
10244 } ## end elsif ($cmd =~ /^(.*)/s)
10245 } ## end sub cmd_pre580_W
10247 =head1 PRE-AND-POST-PROMPT COMMANDS AND ACTIONS
10249 The debugger used to have a bunch of nearly-identical code to handle
10250 the pre-and-post-prompt action commands. C<cmd_pre590_prepost> and
10251 C<cmd_prepost> unify all this into one set of code to handle the
10252 appropriate actions.
10254 =head2 C<cmd_pre590_prepost>
10256 A small wrapper around C<cmd_prepost>; it makes sure that the default doesn't
10257 do something destructive. In pre 5.8 debuggers, the default action was to
10258 delete all the actions.
10262 sub cmd_pre590_prepost {
10264 my $line = shift || '*';
10265 my $dbline = shift;
10267 return cmd_prepost( $cmd, $line, $dbline );
10268 } ## end sub cmd_pre590_prepost
10270 =head2 C<cmd_prepost>
10272 Actually does all the handling for C<E<lt>>, C<E<gt>>, C<{{>, C<{>, etc.
10273 Since the lists of actions are all held in arrays that are pointed to by
10274 references anyway, all we have to do is pick the right array reference and
10275 then use generic code to all, delete, or list actions.
10282 # No action supplied defaults to 'list'.
10283 my $line = shift || '?';
10285 # Figure out what to put in the prompt.
10288 # Make sure we have some array or another to address later.
10289 # This means that if for some reason the tests fail, we won't be
10290 # trying to stash actions or delete them from the wrong place.
10293 # < - Perl code to run before prompt.
10294 if ( $cmd =~ /^\</o ) {
10295 $which = 'pre-perl';
10299 # > - Perl code to run after prompt.
10300 elsif ( $cmd =~ /^\>/o ) {
10301 $which = 'post-perl';
10305 # { - first check for properly-balanced braces.
10306 elsif ( $cmd =~ /^\{/o ) {
10307 if ( $cmd =~ /^\{.*\}$/o && unbalanced( substr( $cmd, 1 ) ) ) {
10309 "$cmd is now a debugger command\nuse ';$cmd' if you mean Perl code\n";
10312 # Properly balanced. Pre-prompt debugger actions.
10314 $which = 'pre-debugger';
10317 } ## end elsif ( $cmd =~ /^\{/o )
10319 # Did we find something that makes sense?
10321 print $OUT "Confused by command: $cmd\n";
10328 if ( $line =~ /^\s*\?\s*$/o ) {
10331 # Nothing there. Complain.
10332 print $OUT "No $which actions.\n";
10336 # List the actions in the selected list.
10337 print $OUT "$which commands:\n";
10338 foreach my $action (@$aref) {
10339 print $OUT "\t$cmd -- $action\n";
10342 } ## end if ( $line =~ /^\s*\?\s*$/o)
10344 # Might be a delete.
10346 if ( length($cmd) == 1 ) {
10347 if ( $line =~ /^\s*\*\s*$/o ) {
10349 # It's a delete. Get rid of the old actions in the
10352 print $OUT "All $cmd actions cleared.\n";
10356 # Replace all the actions. (This is a <, >, or {).
10357 @$aref = action($line);
10359 } ## end if ( length($cmd) == 1)
10360 elsif ( length($cmd) == 2 ) {
10362 # Add the action to the line. (This is a <<, >>, or {{).
10363 push @$aref, action($line);
10367 # <<<, >>>>, {{{{{{ ... something not a command.
10369 "Confused by strange length of $which command($cmd)...\n";
10371 } ## end else [ if ( $line =~ /^\s*\?\s*$/o)
10373 } ## end sub cmd_prepost
10377 Contains the C<at_exit> routine that the debugger uses to issue the
10378 C<Debugged program terminated ...> message after the program completes. See
10379 the L<C<END>|/END PROCESSING - THE END BLOCK> block documentation for more
10387 "Debugged program terminated. Use 'q' to quit or 'R' to restart.";
10390 package DB; # Do not trace this 1; below!