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 C<perl -d>. This documentation tries to outline the
14 structure and services provided by C<perl5db.pl>, and to describe how you
19 The debugger can look pretty forbidding to many Perl programmers. There are
20 a number of reasons for this, many stemming out of the debugger's history.
22 When the debugger was first written, Perl didn't have a lot of its nicer
23 features - no references, no lexical variables, no closures, no object-oriented
24 programming. So a lot of the things one would normally have done using such
25 features was done using global variables, globs and the C<local()> operator
28 Some of these have survived into the current debugger; a few of the more
29 interesting and still-useful idioms are noted in this section, along with notes
30 on the comments themselves.
32 =head2 Why not use more lexicals?
34 Experienced Perl programmers will note that the debugger code tends to use
35 mostly package globals rather than lexically-scoped variables. This is done
36 to allow a significant amount of control of the debugger from outside the
39 Unfortunately, though the variables are accessible, they're not well
40 documented, so it's generally been a decision that hasn't made a lot of
41 difference to most users. Where appropriate, comments have been added to
42 make variables more accessible and usable, with the understanding that these
43 I<are> debugger internals, and are therefore subject to change. Future
44 development should probably attempt to replace the globals with a well-defined
45 API, but for now, the variables are what we've got.
47 =head2 Automated variable stacking via C<local()>
49 As you may recall from reading C<perlfunc>, the C<local()> operator makes a
50 temporary copy of a variable in the current scope. When the scope ends, the
51 old copy is restored. This is often used in the debugger to handle the
52 automatic stacking of variables during recursive calls:
57 # Do some stuff, then ...
61 What happens is that on entry to the subroutine, C<$some_global> is localized,
62 then altered. When the subroutine returns, Perl automatically undoes the
63 localization, restoring the previous value. Voila, automatic stack management.
65 The debugger uses this trick a I<lot>. Of particular note is C<DB::eval>,
66 which lets the debugger get control inside of C<eval>'ed code. The debugger
67 localizes a saved copy of C<$@> inside the subroutine, which allows it to
68 keep C<$@> safe until it C<DB::eval> returns, at which point the previous
69 value of C<$@> is restored. This makes it simple (well, I<simpler>) to keep
70 track of C<$@> inside C<eval>s which C<eval> other C<eval's>.
72 In any case, watch for this pattern. It occurs fairly often.
76 This is used to cleverly reverse the sense of a logical test depending on
77 the value of an auxiliary variable. For instance, the debugger's C<S>
78 (search for subroutines by pattern) allows you to negate the pattern
81 # Find all non-'foo' subs:
84 Boolean algebra states that the truth table for XOR looks like this:
90 (! not present and no match) --> false, don't print
94 (! not present and matches) --> true, print
98 (! present and no match) --> true, print
102 (! present and matches) --> false, don't print
106 As you can see, the first pair applies when C<!> isn't supplied, and
107 the second pair applies when it is. The XOR simply allows us to
108 compact a more complicated if-then-elseif-else into a more elegant
109 (but perhaps overly clever) single test. After all, it needed this
112 =head2 FLAGS, FLAGS, FLAGS
114 There is a certain C programming legacy in the debugger. Some variables,
115 such as C<$single>, C<$trace>, and C<$frame>, have I<magical> values composed
116 of 1, 2, 4, etc. (powers of 2) OR'ed together. This allows several pieces
117 of state to be stored independently in a single scalar.
123 is checking to see if the appropriate bit is on. Since each bit can be
124 "addressed" independently in this way, C<$scalar> is acting sort of like
125 an array of bits. Obviously, since the contents of C<$scalar> are just a
126 bit-pattern, we can save and restore it easily (it will just look like
129 The problem, is of course, that this tends to leave magic numbers scattered
130 all over your program whenever a bit is set, cleared, or checked. So why do
137 First, doing an arithmetical or bitwise operation on a scalar is
138 just about the fastest thing you can do in Perl: C<use constant> actually
139 creates a subroutine call, and array and hash lookups are much slower. Is
140 this over-optimization at the expense of readability? Possibly, but the
141 debugger accesses these variables a I<lot>. Any rewrite of the code will
142 probably have to benchmark alternate implementations and see which is the
143 best balance of readability and speed, and then document how it actually
148 Second, it's very easy to serialize a scalar number. This is done in
149 the restart code; the debugger state variables are saved in C<%ENV> and then
150 restored when the debugger is restarted. Having them be just numbers makes
155 Third, some of these variables are being shared with the Perl core
156 smack in the middle of the interpreter's execution loop. It's much faster for
157 a C program (like the interpreter) to check a bit in a scalar than to access
158 several different variables (or a Perl array).
162 =head2 What are those C<XXX> comments for?
164 Any comment containing C<XXX> means that the comment is either somewhat
165 speculative - it's not exactly clear what a given variable or chunk of
166 code is doing, or that it is incomplete - the basics may be clear, but the
167 subtleties are not completely documented.
169 Send in a patch if you can clear up, fill out, or clarify an C<XXX>.
171 =head1 DATA STRUCTURES MAINTAINED BY CORE
173 There are a number of special data structures provided to the debugger by
174 the Perl interpreter.
176 The array C<@{$main::{'_<'.$filename}}> (aliased locally to C<@dbline>
177 via glob assignment) contains the text from C<$filename>, with each
178 element corresponding to a single line of C<$filename>. Additionally,
179 breakable lines will be dualvars with the numeric component being the
180 memory address of a COP node. Non-breakable lines are dualvar to 0.
182 The hash C<%{'_<'.$filename}> (aliased locally to C<%dbline> via glob
183 assignment) contains breakpoints and actions. The keys are line numbers;
184 you can set individual values, but not the whole hash. The Perl interpreter
185 uses this hash to determine where breakpoints have been set. Any true value is
186 considered to be a breakpoint; C<perl5db.pl> uses C<$break_condition\0$action>.
187 Values are magical in numeric context: 1 if the line is breakable, 0 if not.
189 The scalar C<${"_<$filename"}> simply contains the string C<$filename>.
190 This is also the case for evaluated strings that contain subroutines, or
191 which are currently being executed. The $filename for C<eval>ed strings looks
194 =head1 DEBUGGER STARTUP
196 When C<perl5db.pl> starts, it reads an rcfile (C<perl5db.ini> for
197 non-interactive sessions, C<.perldb> for interactive ones) that can set a number
198 of options. In addition, this file may define a subroutine C<&afterinit>
199 that will be executed (in the debugger's context) after the debugger has
202 Next, it checks the C<PERLDB_OPTS> environment variable and treats its
203 contents as the argument of a C<o> command in the debugger.
205 =head2 STARTUP-ONLY OPTIONS
207 The following options can only be specified at startup.
208 To set them in your rcfile, add a call to
209 C<&parse_options("optionName=new_value")>.
215 the TTY to use for debugging i/o.
219 if set, goes in NonStop mode. On interrupt, if TTY is not set,
220 uses the value of noTTY or F<$HOME/.perldbtty$$> to find TTY using
221 Term::Rendezvous. Current variant is to have the name of TTY in this
226 if false, a dummy ReadLine is used, so you can debug
227 ReadLine applications.
231 if true, no i/o is performed until interrupt.
235 file or pipe to print line number info to. If it is a
236 pipe, a short "emacs like" message is used.
240 host:port to connect to on remote host for remote debugging.
244 file to store session history to. There is no default and so no
245 history file is written unless this variable is explicitly set.
249 number of commands to store to the file specified in C<HistFile>.
256 &parse_options("NonStop=1 LineInfo=db.out");
257 sub afterinit { $trace = 1; }
259 The script will run without human intervention, putting trace
260 information into C<db.out>. (If you interrupt it, you had better
261 reset C<LineInfo> to something I<interactive>!)
263 =head1 INTERNALS DESCRIPTION
265 =head2 DEBUGGER INTERFACE VARIABLES
267 Perl supplies the values for C<%sub>. It effectively inserts
268 a C<&DB::DB();> in front of each place that can have a
269 breakpoint. At each subroutine call, it calls C<&DB::sub> with
270 C<$DB::sub> set to the called subroutine. It also inserts a C<BEGIN
271 {require 'perl5db.pl'}> before the first line.
273 After each C<require>d file is compiled, but before it is executed, a
274 call to C<&DB::postponed($main::{'_<'.$filename})> is done. C<$filename>
275 is the expanded name of the C<require>d file (as found via C<%INC>).
277 =head3 IMPORTANT INTERNAL VARIABLES
281 Used to control when the debugger will attempt to acquire another TTY to be
286 =item * 1 - on C<fork()>
288 =item * 2 - debugger is started inside debugger
290 =item * 4 - on startup
296 The value -2 indicates that no return value should be printed.
297 Any other positive value causes C<DB::sub> to print return values.
301 The item to be eval'ed by C<DB::eval>. Used to prevent messing with the current
302 contents of C<@_> when C<DB::eval> is called.
306 Determines what messages (if any) will get printed when a subroutine (or eval)
307 is entered or exited.
311 =item * 0 - No enter/exit messages
313 =item * 1 - Print I<entering> messages on subroutine entry
315 =item * 2 - Adds exit messages on subroutine exit. If no other flag is on, acts like 1+2.
317 =item * 4 - Extended messages: C<< <in|out> I<context>=I<fully-qualified sub name> from I<file>:I<line> >>. If no other flag is on, acts like 1+4.
319 =item * 8 - Adds parameter information to messages, and overloaded stringify and tied FETCH is enabled on the printed arguments. Ignored if C<4> is not on.
321 =item * 16 - Adds C<I<context> return from I<subname>: I<value>> messages on subroutine/eval exit. Ignored if C<4> is not on.
325 To get everything, use C<$frame=30> (or C<o f=30> as a debugger command).
326 The debugger internally juggles the value of C<$frame> during execution to
327 protect external modules that the debugger uses from getting traced.
331 Tracks current debugger nesting level. Used to figure out how many
332 C<E<lt>E<gt>> pairs to surround the line number with when the debugger
333 outputs a prompt. Also used to help determine if the program has finished
334 during command parsing.
336 =head4 C<$onetimeDump>
338 Controls what (if anything) C<DB::eval()> will print after evaluating an
343 =item * C<undef> - don't print anything
345 =item * C<dump> - use C<dumpvar.pl> to display the value returned
347 =item * C<methods> - print the methods callable on the first item returned
351 =head4 C<$onetimeDumpDepth>
353 Controls how far down C<dumpvar.pl> will go before printing C<...> while
354 dumping a structure. Numeric. If C<undef>, print all levels.
358 Used to track whether or not an C<INT> signal has been detected. C<DB::DB()>,
359 which is called before every statement, checks this and puts the user into
360 command mode if it finds C<$signal> set to a true value.
364 Controls behavior during single-stepping. Stacked in C<@stack> on entry to
365 each subroutine; popped again at the end of each subroutine.
369 =item * 0 - run continuously.
371 =item * 1 - single-step, go into subs. The C<s> command.
373 =item * 2 - single-step, don't go into subs. The C<n> command.
375 =item * 4 - print current sub depth (turned on to force this when C<too much
382 Controls the output of trace information.
386 =item * 1 - The C<t> command was entered to turn on tracing (every line executed is printed)
388 =item * 2 - watch expressions are active
390 =item * 4 - user defined a C<watchfunction()> in C<afterinit()>
394 =head4 C<$slave_editor>
396 1 if C<LINEINFO> was directed to a pipe; 0 otherwise.
400 Stack of filehandles that C<DB::readline()> will read commands from.
401 Manipulated by the debugger's C<source> command and C<DB::readline()> itself.
405 Local alias to the magical line array, C<@{$main::{'_<'.$filename}}> ,
406 supplied by the Perl interpreter to the debugger. Contains the source.
410 Previous values of watch expressions. First set when the expression is
411 entered; reset whenever the watch expression changes.
415 Saves important globals (C<$@>, C<$!>, C<$^E>, C<$,>, C<$/>, C<$\>, C<$^W>)
416 so that the debugger can substitute safe values while it's running, and
417 restore them when it returns control.
421 Saves the current value of C<$single> on entry to a subroutine.
422 Manipulated by the C<c> command to turn off tracing in all subs above the
427 The 'watch' expressions: to be evaluated before each line is executed.
431 The typeahead buffer, used by C<DB::readline>.
435 Command aliases. Stored as character strings to be substituted for a command
438 =head4 C<%break_on_load>
440 Keys are file names, values are 1 (break when this file is loaded) or undef
441 (don't break when it is loaded).
445 Keys are line numbers, values are C<condition\0action>. If used in numeric
446 context, values are 0 if not breakable, 1 if breakable, no matter what is
447 in the actual hash entry.
449 =head4 C<%had_breakpoints>
451 Keys are file names; values are bitfields:
455 =item * 1 - file has a breakpoint in it.
457 =item * 2 - file has an action in it.
461 A zero or undefined value means this file has neither.
465 Stores the debugger options. These are character string values.
469 Saves breakpoints for code that hasn't been compiled yet.
470 Keys are subroutine names, values are:
474 =item * C<compile> - break when this sub is compiled
476 =item * C<< break +0 if <condition> >> - break (conditionally) at the start of this routine. The condition will be '1' if no condition was specified.
480 =head4 C<%postponed_file>
482 This hash keeps track of breakpoints that need to be set for files that have
483 not yet been compiled. Keys are filenames; values are references to hashes.
484 Each of these hashes is keyed by line number, and its values are breakpoint
485 definitions (C<condition\0action>).
487 =head1 DEBUGGER INITIALIZATION
489 The debugger's initialization actually jumps all over the place inside this
490 package. This is because there are several BEGIN blocks (which of course
491 execute immediately) spread through the code. Why is that?
493 The debugger needs to be able to change some things and set some things up
494 before the debugger code is compiled; most notably, the C<$deep> variable that
495 C<DB::sub> uses to tell when a program has recursed deeply. In addition, the
496 debugger has to turn off warnings while the debugger code is compiled, but then
497 restore them to their original setting before the program being debugged begins
500 The first C<BEGIN> block simply turns off warnings by saving the current
501 setting of C<$^W> and then setting it to zero. The second one initializes
502 the debugger variables that are needed before the debugger begins executing.
503 The third one puts C<$^X> back to its former value.
505 We'll detail the second C<BEGIN> block later; just remember that if you need
506 to initialize something before the debugger starts really executing, that's
519 BEGIN {eval 'use IO::Handle'}; # Needed for flush only? breaks under miniperl
523 $^V =~ /^v(\d+\.\d+)/;
524 feature->import(":$1");
525 $_initial_cwd = Cwd::getcwd();
528 # Debugger for Perl 5.00x; perl5db.pl patch level:
529 use vars qw($VERSION $header);
531 # bump to X.XX in blead, only use X.XX_XX in maint
534 $header = "perl5db.pl version $VERSION";
536 =head1 DEBUGGER ROUTINES
540 This function replaces straight C<eval()> inside the debugger; it simplifies
541 the process of evaluating code in the user's context.
543 The code to be evaluated is passed via the package global variable
544 C<$DB::evalarg>; this is done to avoid fiddling with the contents of C<@_>.
546 Before we do the C<eval()>, we preserve the current settings of C<$trace>,
547 C<$single>, C<$^D> and C<$usercontext>. The latter contains the
548 preserved values of C<$@>, C<$!>, C<$^E>, C<$,>, C<$/>, C<$\>, C<$^W> and the
549 user's current package, grabbed when C<DB::DB> got control. This causes the
550 proper context to be used when the eval is actually done. Afterward, we
551 restore C<$trace>, C<$single>, and C<$^D>.
553 Next we need to handle C<$@> without getting confused. We save C<$@> in a
554 local lexical, localize C<$saved[0]> (which is where C<save()> will put
555 C<$@>), and then call C<save()> to capture C<$@>, C<$!>, C<$^E>, C<$,>,
556 C<$/>, C<$\>, and C<$^W>) and set C<$,>, C<$/>, C<$\>, and C<$^W> to values
557 considered sane by the debugger. If there was an C<eval()> error, we print
558 it on the debugger's output. If C<$onetimedump> is defined, we call
559 C<dumpit> if it's set to 'dump', or C<methods> if it's set to
560 'methods'. Setting it to something else causes the debugger to do the eval
561 but not print the result - handy if you want to do something else with it
562 (the "watch expressions" code does this to get the value of the watch
563 expression but not show it unless it matters).
565 In any case, we then return the list of output from C<eval> to the caller,
566 and unwinding restores the former version of C<$@> in C<@saved> as well
567 (the localization of C<$saved[0]> goes away at the end of this scope).
569 =head3 Parameters and variables influencing execution of DB::eval()
571 C<DB::eval> isn't parameterized in the standard way; this is to keep the
572 debugger's calls to C<DB::eval()> from mucking with C<@_>, among other things.
573 The variables listed below influence C<DB::eval()>'s execution directly.
577 =item C<$evalarg> - the thing to actually be eval'ed
579 =item C<$trace> - Current state of execution tracing
581 =item C<$single> - Current state of single-stepping
583 =item C<$onetimeDump> - what is to be displayed after the evaluation
585 =item C<$onetimeDumpDepth> - how deep C<dumpit()> should go when dumping results
589 The following variables are altered by C<DB::eval()> during its execution. They
590 are "stacked" via C<local()>, enabling recursive calls to C<DB::eval()>.
594 =item C<@res> - used to capture output from actual C<eval>.
596 =item C<$otrace> - saved value of C<$trace>.
598 =item C<$osingle> - saved value of C<$single>.
600 =item C<$od> - saved value of C<$^D>.
602 =item C<$saved[0]> - saved value of C<$@>.
604 =item $\ - for output of C<$@> if there is an evaluation error.
608 =head3 The problem of lexicals
610 The context of C<DB::eval()> presents us with some problems. Obviously,
611 we want to be 'sandboxed' away from the debugger's internals when we do
612 the eval, but we need some way to control how punctuation variables and
613 debugger globals are used.
615 We can't use local, because the code inside C<DB::eval> can see localized
616 variables; and we can't use C<my> either for the same reason. The code
617 in this routine compromises and uses C<my>.
619 After this routine is over, we don't have user code executing in the debugger's
620 context, so we can use C<my> freely.
624 ############################################## Begin lexical danger zone
626 # 'my' variables used here could leak into (that is, be visible in)
627 # the context that the code being evaluated is executing in. This means that
628 # the code could modify the debugger's variables.
630 # Fiddling with the debugger's context could be Bad. We insulate things as
695 # Used to save @ARGV and extract any debugger-related flags.
698 # Used to prevent multiple entries to diesignal()
699 # (if for instance diesignal() itself dies)
702 # Used to prevent the debugger from running nonstop
706 sub _calc_usercontext {
709 # Cancel strict completely for the evaluated code, so the code
710 # the user evaluates won't be affected by it. (Shlomi Fish)
711 return 'no strict; ($@, $!, $^E, $,, $/, $\, $^W) = @DB::saved;'
712 . "package $package;"; # this won't let them modify, alas
717 # 'my' would make it visible from user code
718 # but so does local! --tchrist
719 # Remember: this localizes @DB::res, not @main::res.
723 # Try to keep the user code from messing with us. Save these so that
724 # even if the eval'ed code changes them, we can put them back again.
725 # Needed because the user could refer directly to the debugger's
726 # package globals (and any 'my' variables in this containing scope)
727 # inside the eval(), and we want to try to stay safe.
728 local $otrace = $trace;
729 local $osingle = $single;
732 # Untaint the incoming eval() argument.
733 { ($evalarg) = $evalarg =~ /(.*)/s; }
735 # $usercontext built in DB::DB near the comment
736 # "set up the context for DB::eval ..."
737 # Evaluate and save any results.
738 @res = eval "$usercontext $evalarg;\n"; # '\n' for nice recursive debug
740 # Restore those old values.
746 # Save the current value of $@, and preserve it in the debugger's copy
747 # of the saved precious globals.
750 # Since we're only saving $@, we only have to localize the array element
751 # that it will be stored in.
752 local $saved[0]; # Preserve the old value of $@
755 # Now see whether we need to report an error back to the user.
761 # Display as required by the caller. $onetimeDump and $onetimedumpDepth
762 # are package globals.
763 elsif ($onetimeDump) {
764 if ( $onetimeDump eq 'dump' ) {
765 local $option{dumpDepth} = $onetimedumpDepth
766 if defined $onetimedumpDepth;
767 dumpit( $OUT, \@res );
769 elsif ( $onetimeDump eq 'methods' ) {
772 } ## end elsif ($onetimeDump)
776 ############################################## End lexical danger zone
778 # After this point it is safe to introduce lexicals.
779 # The code being debugged will be executing in its own context, and
780 # can't see the inside of the debugger.
782 # However, one should not overdo it: leave as much control from outside as
783 # possible. If you make something a lexical, it's not going to be addressable
784 # from outside the debugger even if you know its name.
786 # This file is automatically included if you do perl -d.
787 # It's probably not useful to include this yourself.
789 # Before venturing further into these twisty passages, it is
790 # wise to read the perldebguts man page or risk the ire of dragons.
792 # (It should be noted that perldebguts will tell you a lot about
793 # the underlying mechanics of how the debugger interfaces into the
794 # Perl interpreter, but not a lot about the debugger itself. The new
795 # comments in this code try to address this problem.)
797 # Note that no subroutine call is possible until &DB::sub is defined
798 # (for subroutines defined outside of the package DB). In fact the same is
799 # true if $deep is not defined.
801 # Enhanced by ilya@math.ohio-state.edu (Ilya Zakharevich)
803 # modified Perl debugger, to be run from Emacs in perldb-mode
804 # Ray Lischner (uunet!mntgfx!lisch) as of 5 Nov 1990
805 # Johan Vromans -- upgrade to 4.0 pl 10
806 # Ilya Zakharevich -- patches after 5.001 (and some before ;-)
807 ########################################################################
809 =head1 DEBUGGER INITIALIZATION
811 The debugger starts up in phases.
815 First, it initializes the environment it wants to run in: turning off
816 warnings during its own compilation, defining variables which it will need
817 to avoid warnings later, setting itself up to not exit when the program
818 terminates, and defaulting to printing return values for the C<r> command.
822 # Needed for the statement after exec():
824 # This BEGIN block is simply used to switch off warnings during debugger
825 # compilation. Probably it would be better practice to fix the warnings,
826 # but this is how it's done at the moment.
831 } # Switch compilation warnings off until another BEGIN.
833 local ($^W) = 0; # Switch run-time warnings off during init.
835 =head2 THREADS SUPPORT
837 If we are running under a threaded Perl, we require threads and threads::shared
838 if the environment variable C<PERL5DB_THREADED> is set, to enable proper
839 threaded debugger control. C<-dt> can also be used to set this.
841 Each new thread will be announced and the debugger prompt will always inform
842 you of each new thread created. It will also indicate the thread id in which
843 we are currently running within the prompt like this:
847 Where C<[tid]> is an integer thread id and C<$i> is the familiar debugger
848 command prompt. The prompt will show: C<[0]> when running under threads, but
849 not actually in a thread. C<[tid]> is consistent with C<gdb> usage.
851 While running under threads, when you set or delete a breakpoint (etc.), this
852 will apply to all threads, not just the currently running one. When you are
853 in a currently executing thread, you will stay there until it completes. With
854 the current implementation it is not currently possible to hop from one thread
857 The C<e> and C<E> commands are currently fairly minimal - see C<h e> and C<h E>.
859 Note that threading support was built into the debugger as of Perl version
860 C<5.8.6> and debugger version C<1.2.8>.
865 # ensure we can share our non-threaded variables or no-op
866 if ($ENV{PERL5DB_THREADED}) {
868 require threads::shared;
869 import threads::shared qw(share);
873 print "Threads support enabled\n";
876 *share = sub(\[$@%]) {};
880 # These variables control the execution of 'dumpvar.pl'.
895 # used to control die() reporting in diesignal()
898 use vars qw($CarpLevel);
901 # without threads, $filename is not defined until DB::DB is called
902 share($main::{'_<'.$filename}) if defined $filename;
904 # Command-line + PERLLIB:
905 # Save the contents of @INC before they are modified elsewhere.
908 # This was an attempt to clear out the previous values of various
909 # trapped errors. Apparently it didn't help. XXX More info needed!
910 # $prevwarn = $prevdie = $prevbus = $prevsegv = ''; # Does not help?!
912 # We set these variables to safe values. We don't want to blindly turn
913 # off warnings, because other packages may still want them.
914 $trace = $signal = $single = 0; # Uninitialized warning suppression
915 # (local $^W cannot help - other packages!).
917 # Default to not exiting when program finishes; print the return
918 # value when the 'r' command is used to return from a subroutine.
919 $inhibit_exit = $option{PrintRet} = 1;
921 use vars qw($trace_to_depth);
923 # Default to 1E9 so it won't be limited to a certain recursion depth.
924 $trace_to_depth = 1E9;
926 =head1 OPTION PROCESSING
928 The debugger's options are actually spread out over the debugger itself and
929 C<dumpvar.pl>; some of these are variables to be set, while others are
930 subs to be called with a value. To try to make this a little easier to
931 manage, the debugger uses a few data structures to define what options
932 are legal and how they are to be processed.
934 First, the C<@options> array defines the I<names> of all the options that
940 CommandSet HistFile HistSize
941 hashDepth arrayDepth dumpDepth
942 DumpDBFiles DumpPackages DumpReused
943 compactDump veryCompact quote
944 HighBit undefPrint globPrint
945 PrintRet UsageOnly frame
947 ReadLine NonStop LineInfo
948 maxTraceLen recallCommand ShellBang
949 pager tkRunning ornaments
950 signalLevel warnLevel dieLevel
951 inhibit_exit ImmediateStop bareStringify
952 CreateTTY RemotePort windowSize
956 @RememberOnROptions = qw(DollarCaretP);
960 Second, C<optionVars> lists the variables that each option uses to save its
965 use vars qw(%optionVars);
968 hashDepth => \$dumpvar::hashDepth,
969 arrayDepth => \$dumpvar::arrayDepth,
970 CommandSet => \$CommandSet,
971 DumpDBFiles => \$dumpvar::dumpDBFiles,
972 DumpPackages => \$dumpvar::dumpPackages,
973 DumpReused => \$dumpvar::dumpReused,
974 HighBit => \$dumpvar::quoteHighBit,
975 undefPrint => \$dumpvar::printUndef,
976 globPrint => \$dumpvar::globPrint,
977 UsageOnly => \$dumpvar::usageOnly,
978 CreateTTY => \$CreateTTY,
979 bareStringify => \$dumpvar::bareStringify,
981 AutoTrace => \$trace,
982 inhibit_exit => \$inhibit_exit,
983 maxTraceLen => \$maxtrace,
984 ImmediateStop => \$ImmediateStop,
985 RemotePort => \$remoteport,
986 windowSize => \$window,
987 HistFile => \$histfile,
988 HistSize => \$histsize,
993 Third, C<%optionAction> defines the subroutine to be called to process each
998 use vars qw(%optionAction);
1001 compactDump => \&dumpvar::compactDump,
1002 veryCompact => \&dumpvar::veryCompact,
1003 quote => \&dumpvar::quote,
1006 ReadLine => \&ReadLine,
1007 NonStop => \&NonStop,
1008 LineInfo => \&LineInfo,
1009 recallCommand => \&recallCommand,
1010 ShellBang => \&shellBang,
1012 signalLevel => \&signalLevel,
1013 warnLevel => \&warnLevel,
1014 dieLevel => \&dieLevel,
1015 tkRunning => \&tkRunning,
1016 ornaments => \&ornaments,
1017 RemotePort => \&RemotePort,
1018 DollarCaretP => \&DollarCaretP,
1023 Last, the C<%optionRequire> notes modules that must be C<require>d if an
1028 # Note that this list is not complete: several options not listed here
1029 # actually require that dumpvar.pl be loaded for them to work, but are
1030 # not in the table. A subsequent patch will correct this problem; for
1031 # the moment, we're just recommenting, and we are NOT going to change
1033 use vars qw(%optionRequire);
1036 compactDump => 'dumpvar.pl',
1037 veryCompact => 'dumpvar.pl',
1038 quote => 'dumpvar.pl',
1043 There are a number of initialization-related variables which can be set
1044 by putting code to set them in a BEGIN block in the C<PERL5DB> environment
1045 variable. These are:
1049 =item C<$rl> - readline control XXX needs more explanation
1051 =item C<$warnLevel> - whether or not debugger takes over warning handling
1053 =item C<$dieLevel> - whether or not debugger takes over die handling
1055 =item C<$signalLevel> - whether or not debugger takes over signal handling
1057 =item C<$pre> - preprompt actions (array reference)
1059 =item C<$post> - postprompt actions (array reference)
1063 =item C<$CreateTTY> - whether or not to create a new TTY for this debugger
1065 =item C<$CommandSet> - which command set to use (defaults to new, documented set)
1071 # These guys may be defined in $ENV{PERL5DB} :
1072 $rl = 1 unless defined $rl;
1073 $warnLevel = 1 unless defined $warnLevel;
1074 $dieLevel = 1 unless defined $dieLevel;
1075 $signalLevel = 1 unless defined $signalLevel;
1076 $pre = [] unless defined $pre;
1077 $post = [] unless defined $post;
1078 $pretype = [] unless defined $pretype;
1079 $CreateTTY = 3 unless defined $CreateTTY;
1080 $CommandSet = '580' unless defined $CommandSet;
1085 share($signalLevel);
1095 The default C<die>, C<warn>, and C<signal> handlers are set up.
1099 warnLevel($warnLevel);
1100 dieLevel($dieLevel);
1101 signalLevel($signalLevel);
1105 The pager to be used is needed next. We try to get it from the
1106 environment first. If it's not defined there, we try to find it in
1107 the Perl C<Config.pm>. If it's not there, we default to C<more>. We
1108 then call the C<pager()> function to save the pager name.
1112 # This routine makes sure $pager is set up so that '|' can use it.
1115 # If PAGER is defined in the environment, use it.
1119 # If not, see if Config.pm defines it.
1120 : eval { require Config }
1121 && defined $Config::Config{pager}
1122 ? $Config::Config{pager}
1124 # If not, fall back to 'more'.
1127 unless defined $pager;
1131 We set up the command to be used to access the man pages, the command
1132 recall character (C<!> unless otherwise defined) and the shell escape
1133 character (C<!> unless otherwise defined). Yes, these do conflict, and
1134 neither works in the debugger at the moment.
1140 # Set up defaults for command recall and shell escape (note:
1141 # these currently don't work in linemode debugging).
1142 recallCommand("!") unless defined $prc;
1143 shellBang("!") unless defined $psh;
1147 We then set up the gigantic string containing the debugger help.
1148 We also set the limit on the number of arguments we'll display during a
1155 # If we didn't get a default for the length of eval/stack trace args,
1157 $maxtrace = 400 unless defined $maxtrace;
1159 =head2 SETTING UP THE DEBUGGER GREETING
1161 The debugger I<greeting> helps to inform the user how many debuggers are
1162 running, and whether the current debugger is the primary or a child.
1164 If we are the primary, we just hang onto our pid so we'll have it when
1165 or if we start a child debugger. If we are a child, we'll set things up
1166 so we'll have a unique greeting and so the parent will give us our own
1169 We save the current contents of the C<PERLDB_PIDS> environment variable
1170 because we mess around with it. We'll also need to hang onto it because
1171 we'll need it if we restart.
1173 Child debuggers make a label out of the current PID structure recorded in
1174 PERLDB_PIDS plus the new PID. They also mark themselves as not having a TTY
1175 yet so the parent will give them one later via C<resetterm()>.
1179 # Save the current contents of the environment; we're about to
1180 # much with it. We'll need this if we have to restart.
1181 use vars qw($ini_pids);
1182 $ini_pids = $ENV{PERLDB_PIDS};
1184 use vars qw ($pids $term_pid);
1186 if ( defined $ENV{PERLDB_PIDS} ) {
1188 # We're a child. Make us a label out of the current PID structure
1189 # recorded in PERLDB_PIDS plus our (new) PID. Mark us as not having
1190 # a term yet so the parent will give us one later via resetterm().
1192 my $env_pids = $ENV{PERLDB_PIDS};
1193 $pids = "[$env_pids]";
1195 # Unless we are on OpenVMS, all programs under the DCL shell run under
1198 if (($^O eq 'VMS') && ($env_pids =~ /\b$$\b/)) {
1202 $ENV{PERLDB_PIDS} .= "->$$";
1206 } ## end if (defined $ENV{PERLDB_PIDS...
1209 # We're the parent PID. Initialize PERLDB_PID in case we end up with a
1210 # child debugger, and mark us as the parent, so we'll know to set up
1211 # more TTY's is we have to.
1212 $ENV{PERLDB_PIDS} = "$$";
1217 use vars qw($pidprompt);
1220 # Sets up $emacs as a synonym for $slave_editor.
1221 our ($slave_editor);
1222 *emacs = $slave_editor if $slave_editor; # May be used in afterinit()...
1224 =head2 READING THE RC FILE
1226 The debugger will read a file of initialization options if supplied. If
1227 running interactively, this is C<.perldb>; if not, it's C<perldb.ini>.
1231 # As noted, this test really doesn't check accurately that the debugger
1232 # is running at a terminal or not.
1234 use vars qw($rcfile);
1236 my $dev_tty = (($^O eq 'VMS') ? 'TT:' : '/dev/tty');
1237 # this is the wrong metric!
1238 $rcfile = ((-e $dev_tty) ? ".perldb" : "perldb.ini");
1243 The debugger does a safety test of the file to be read. It must be owned
1244 either by the current user or root, and must only be writable by the owner.
1248 # This wraps a safety test around "do" to read and evaluate the init file.
1250 # This isn't really safe, because there's a race
1251 # between checking and opening. The solution is to
1252 # open and fstat the handle, but then you have to read and
1253 # eval the contents. But then the silly thing gets
1254 # your lexical scope, which is unfortunate at best.
1258 # Just exactly what part of the word "CORE::" don't you understand?
1259 local $SIG{__WARN__};
1260 local $SIG{__DIE__};
1262 unless ( is_safe_file($file) ) {
1263 CORE::warn <<EO_GRIPE;
1264 perldb: Must not source insecure rcfile $file.
1265 You or the superuser must be the owner, and it must not
1266 be writable by anyone but its owner.
1269 } ## end unless (is_safe_file($file...
1272 CORE::warn("perldb: couldn't parse $file: $@") if $@;
1273 } ## end sub safe_do
1275 # This is the safety test itself.
1277 # Verifies that owner is either real user or superuser and that no
1278 # one but owner may write to it. This function is of limited use
1279 # when called on a path instead of upon a handle, because there are
1280 # no guarantees that filename (by dirent) whose file (by ino) is
1281 # eventually accessed is the same as the one tested.
1282 # Assumes that the file's existence is not in doubt.
1285 stat($path) || return; # mysteriously vaporized
1286 my ( $dev, $ino, $mode, $nlink, $uid, $gid ) = stat(_);
1288 return 0 if $uid != 0 && $uid != $<;
1289 return 0 if $mode & 022;
1291 } ## end sub is_safe_file
1293 # If the rcfile (whichever one we decided was the right one to read)
1294 # exists, we safely do it.
1296 safe_do("./$rcfile");
1299 # If there isn't one here, try the user's home directory.
1300 elsif ( defined $ENV{HOME} && -f "$ENV{HOME}/$rcfile" ) {
1301 safe_do("$ENV{HOME}/$rcfile");
1304 # Else try the login directory.
1305 elsif ( defined $ENV{LOGDIR} && -f "$ENV{LOGDIR}/$rcfile" ) {
1306 safe_do("$ENV{LOGDIR}/$rcfile");
1309 # If the PERLDB_OPTS variable has options in it, parse those out next.
1310 if ( defined $ENV{PERLDB_OPTS} ) {
1311 parse_options( $ENV{PERLDB_OPTS} );
1316 The last thing we do during initialization is determine which subroutine is
1317 to be used to obtain a new terminal when a new debugger is started. Right now,
1318 the debugger only handles TCP sockets, X11, OS/2, amd Mac OS X
1323 # Set up the get_fork_TTY subroutine to be aliased to the proper routine.
1324 # Works if you're running an xterm or xterm-like window, or you're on
1325 # OS/2, or on Mac OS X. This may need some expansion.
1327 if (not defined &get_fork_TTY) # only if no routine exists
1329 if ( defined $remoteport ) {
1330 # Expect an inetd-like server
1331 *get_fork_TTY = \&socket_get_fork_TTY; # to listen to us
1333 elsif (defined $ENV{TERM} # If we know what kind
1334 # of terminal this is,
1335 and $ENV{TERM} eq 'xterm' # and it's an xterm,
1336 and defined $ENV{DISPLAY} # and what display it's on,
1339 *get_fork_TTY = \&xterm_get_fork_TTY; # use the xterm version
1341 elsif ( $ENV{TMUX} ) {
1342 *get_fork_TTY = \&tmux_get_fork_TTY;
1344 elsif ( $^O eq 'os2' ) { # If this is OS/2,
1345 *get_fork_TTY = \&os2_get_fork_TTY; # use the OS/2 version
1347 elsif ( $^O eq 'darwin' # If this is Mac OS X
1348 and defined $ENV{TERM_PROGRAM} # and we're running inside
1349 and $ENV{TERM_PROGRAM}
1350 eq 'Apple_Terminal' # Terminal.app
1353 *get_fork_TTY = \&macosx_get_fork_TTY; # use the Mac OS X version
1355 } ## end if (not defined &get_fork_TTY...
1357 # untaint $^O, which may have been tainted by the last statement.
1358 # see bug [perl #24674]
1362 # Here begin the unreadable code. It needs fixing.
1364 =head2 RESTART PROCESSING
1366 This section handles the restart command. When the C<R> command is invoked, it
1367 tries to capture all of the state it can into environment variables, and
1368 then sets C<PERLDB_RESTART>. When we start executing again, we check to see
1369 if C<PERLDB_RESTART> is there; if so, we reload all the information that
1370 the R command stuffed into the environment variables.
1372 PERLDB_RESTART - flag only, contains no restart data itself.
1373 PERLDB_HIST - command history, if it's available
1374 PERLDB_ON_LOAD - breakpoints set by the rc file
1375 PERLDB_POSTPONE - subs that have been loaded/not executed,
1377 PERLDB_VISITED - files that had breakpoints
1378 PERLDB_FILE_... - breakpoints for a file
1379 PERLDB_OPT - active options
1380 PERLDB_INC - the original @INC
1381 PERLDB_PRETYPE - preprompt debugger actions
1382 PERLDB_PRE - preprompt Perl code
1383 PERLDB_POST - post-prompt Perl code
1384 PERLDB_TYPEAHEAD - typeahead captured by readline()
1386 We chug through all these variables and plug the values saved in them
1387 back into the appropriate spots in the debugger.
1391 use vars qw(%postponed_file @typeahead);
1393 our (@hist, @truehist);
1395 sub _restore_shared_globals_after_restart
1397 @hist = get_list('PERLDB_HIST');
1398 %break_on_load = get_list("PERLDB_ON_LOAD");
1399 %postponed = get_list("PERLDB_POSTPONE");
1403 share(%break_on_load);
1407 sub _restore_breakpoints_and_actions {
1409 my @had_breakpoints = get_list("PERLDB_VISITED");
1411 for my $file_idx ( 0 .. $#had_breakpoints ) {
1412 my $filename = $had_breakpoints[$file_idx];
1413 my %pf = get_list("PERLDB_FILE_$file_idx");
1414 $postponed_file{ $filename } = \%pf if %pf;
1415 my @lines = sort {$a <=> $b} keys(%pf);
1416 my @enabled_statuses = get_list("PERLDB_FILE_ENABLED_$file_idx");
1417 for my $line_idx (0 .. $#lines) {
1418 _set_breakpoint_enabled_status(
1421 ($enabled_statuses[$line_idx] ? 1 : ''),
1429 sub _restore_options_after_restart
1431 my %options_map = get_list("PERLDB_OPT");
1433 while ( my ( $opt, $val ) = each %options_map ) {
1434 $val =~ s/[\\\']/\\$1/g;
1435 parse_options("$opt'$val'");
1441 sub _restore_globals_after_restart
1443 # restore original @INC
1444 @INC = get_list("PERLDB_INC");
1447 # return pre/postprompt actions and typeahead buffer
1448 $pretype = [ get_list("PERLDB_PRETYPE") ];
1449 $pre = [ get_list("PERLDB_PRE") ];
1450 $post = [ get_list("PERLDB_POST") ];
1451 @typeahead = get_list( "PERLDB_TYPEAHEAD", @typeahead );
1457 if ( exists $ENV{PERLDB_RESTART} ) {
1459 # We're restarting, so we don't need the flag that says to restart anymore.
1460 delete $ENV{PERLDB_RESTART};
1463 _restore_shared_globals_after_restart();
1465 _restore_breakpoints_and_actions();
1468 _restore_options_after_restart();
1470 _restore_globals_after_restart();
1471 } ## end if (exists $ENV{PERLDB_RESTART...
1473 =head2 SETTING UP THE TERMINAL
1475 Now, we'll decide how the debugger is going to interact with the user.
1476 If there's no TTY, we set the debugger to run non-stop; there's not going
1477 to be anyone there to enter commands.
1481 use vars qw($notty $console $tty $LINEINFO);
1482 use vars qw($lineinfo $doccmd);
1486 # Local autoflush to avoid rt#116769,
1487 # as calling IO::File methods causes an unresolvable loop
1488 # that results in debugger failure.
1490 my $o = select($_[0]);
1502 If there is a TTY, we have to determine who it belongs to before we can
1503 proceed. If this is a slave editor or graphical debugger (denoted by
1504 the first command-line switch being '-emacs'), we shift this off and
1505 set C<$rl> to 0 (XXX ostensibly to do straight reads).
1511 # Is Perl being run from a slave editor or graphical debugger?
1512 # If so, don't use readline, and set $slave_editor = 1.
1513 if ($slave_editor = ( @main::ARGV && ( $main::ARGV[0] eq '-emacs' ) )) {
1518 #require Term::ReadLine;
1522 We then determine what the console should be on various systems:
1526 =item * Cygwin - We use C<stdin> instead of a separate device.
1530 if ( $^O eq 'cygwin' ) {
1532 # /dev/tty is binary. use stdin for textmode
1536 =item * Windows or MSDOS - use C<con>.
1540 elsif ( $^O eq 'dos' or -e "con" or $^O eq 'MSWin32' ) {
1544 =item * AmigaOS - use C<CONSOLE:>.
1548 elsif ( $^O eq 'amigaos' ) {
1549 $console = "CONSOLE:";
1552 =item * VMS - use C<sys$command>.
1556 elsif ($^O eq 'VMS') {
1557 $console = 'sys$command';
1560 # Keep this penultimate, on the grounds that it satisfies a wide variety of
1561 # Unix-like systems that would otherwise need to be identified individually.
1563 =item * Unix - use F</dev/tty>.
1567 elsif ( -e "/dev/tty" ) {
1568 $console = "/dev/tty";
1574 _db_warn("Can't figure out your console, using stdin");
1582 Several other systems don't use a specific console. We C<undef $console>
1583 for those (Windows using a slave editor/graphical debugger, NetWare, OS/2
1584 with a slave editor).
1588 if ( ( $^O eq 'MSWin32' ) and ( $slave_editor or defined $ENV{EMACS} ) ) {
1590 # /dev/tty is binary. use stdin for textmode
1594 if ( $^O eq 'NetWare' ) {
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 ( $slave_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 slave 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 $slave_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 .. $stack_depth) {
2120 sub _DB__handle_forward_slash_command {
2123 # The pattern as a string.
2124 use vars qw($inpat);
2126 if (($inpat) = $cmd =~ m#\A/(.*)\z#) {
2128 # Remove the final slash.
2129 $inpat =~ s:([^\\])/$:$1:;
2131 # If the pattern isn't null ...
2132 if ( $inpat ne "" ) {
2134 # Turn off warn and die processing for a bit.
2135 local $SIG{__DIE__};
2136 local $SIG{__WARN__};
2138 # Create the pattern.
2139 eval 'no strict q/vars/; $inpat =~ m' . "\a$inpat\a";
2142 # Oops. Bad pattern. No biscuit.
2143 # Print the eval error and go back for more
2149 } ## end if ($inpat ne "")
2151 # Set up to stop on wrap-around.
2154 # Don't move off the current line.
2157 my $pat = $obj->pat;
2159 # Done in eval so nothing breaks if the pattern
2160 # does something weird.
2165 # Move ahead one line.
2168 # Wrap if we pass the last line.
2169 if ($start > $max) {
2173 # Stop if we have gotten back to this line again,
2174 last if ($start == $end);
2176 # A hit! (Note, though, that we are doing
2177 # case-insensitive matching. Maybe a qr//
2178 # expression would be better, so the user could
2179 # do case-sensitive matching if desired.
2180 if ($dbline[$start] =~ m/$pat/i) {
2181 if ($slave_editor) {
2182 # Handle proper escaping in the slave.
2183 print {$OUT} "\032\032$filename:$start:0\n";
2186 # Just print the line normally.
2187 print {$OUT} "$start:\t",$dbline[$start],"\n";
2189 # And quit since we found something.
2199 # If we wrapped, there never was a match.
2200 if ( $start == $end ) {
2201 print {$OUT} "/$pat/: not found\n";
2209 sub _DB__handle_question_mark_command {
2212 # ? - backward pattern search.
2213 if (my ($inpat) = $cmd =~ m#\A\?(.*)\z#) {
2215 # Get the pattern, remove trailing question mark.
2216 $inpat =~ s:([^\\])\?$:$1:;
2218 # If we've got one ...
2219 if ( $inpat ne "" ) {
2221 # Turn off die & warn handlers.
2222 local $SIG{__DIE__};
2223 local $SIG{__WARN__};
2224 eval '$inpat =~ m' . "\a$inpat\a";
2228 # Ouch. Not good. Print the error.
2233 } ## end if ($inpat ne "")
2235 # Where we are now is where to stop after wraparound.
2238 # Don't move away from this line.
2241 my $pat = $obj->pat;
2242 # Search inside the eval to prevent pattern badness
2250 # Wrap if we pass the first line.
2252 $start = $max if ($start <= 0);
2254 # Quit if we get back where we started,
2255 last if ($start == $end);
2258 if ($dbline[$start] =~ m/$pat/i) {
2259 if ($slave_editor) {
2260 # Yep, follow slave editor requirements.
2261 print $OUT "\032\032$filename:$start:0\n";
2264 # Yep, just print normally.
2265 print $OUT "$start:\t",$dbline[$start],"\n";
2274 # Say we failed if the loop never found anything,
2275 if ( $start == $end ) {
2276 print {$OUT} "?$pat?: not found\n";
2284 sub _DB__handle_restart_and_rerun_commands {
2287 my $cmd_cmd = $obj->cmd_verb;
2288 my $cmd_params = $obj->cmd_args;
2289 # R - restart execution.
2290 # rerun - controlled restart execution.
2291 if ($cmd_cmd eq 'rerun' or $cmd_params eq '') {
2293 # Change directory to the initial current working directory on
2294 # the script startup, so if the debugged program changed the
2295 # directory, then we will still be able to find the path to the
2296 # the program. (perl 5 RT #121509 ).
2297 chdir ($_initial_cwd);
2299 my @args = ($cmd_cmd eq 'R' ? restart() : rerun($cmd_params));
2301 # Close all non-system fds for a clean restart. A more
2302 # correct method would be to close all fds that were not
2303 # open when the process started, but this seems to be
2304 # hard. See "debugger 'R'estart and open database
2305 # connections" on p5p.
2307 my $max_fd = 1024; # default if POSIX can't be loaded
2308 if (eval { require POSIX }) {
2309 eval { $max_fd = POSIX::sysconf(POSIX::_SC_OPEN_MAX()) };
2312 if (defined $max_fd) {
2313 foreach ($^F+1 .. $max_fd-1) {
2314 next unless open FD_TO_CLOSE, "<&=$_";
2319 # And run Perl again. We use exec() to keep the
2320 # PID stable (and that way $ini_pids is still valid).
2321 exec(@args) or print {$OUT} "exec failed: $!\n";
2329 sub _DB__handle_run_command_in_pager_command {
2332 if ($cmd =~ m#\A\|\|?\s*[^|]#) {
2333 if ( $pager =~ /^\|/ ) {
2335 # Default pager is into a pipe. Redirect I/O.
2336 open( SAVEOUT, ">&STDOUT" )
2337 || _db_warn("Can't save STDOUT");
2338 open( STDOUT, ">&OUT" )
2339 || _db_warn("Can't redirect STDOUT");
2340 } ## end if ($pager =~ /^\|/)
2343 # Not into a pipe. STDOUT is safe.
2344 open( SAVEOUT, ">&OUT" ) || _db_warn("Can't save DB::OUT");
2347 # Fix up environment to record we have less if so.
2350 unless ( $obj->piped(scalar ( open( OUT, $pager ) ) ) ) {
2352 # Couldn't open pipe to pager.
2353 _db_warn("Can't pipe output to '$pager'");
2354 if ( $pager =~ /^\|/ ) {
2356 # Redirect I/O back again.
2357 open( OUT, ">&STDOUT" ) # XXX: lost message
2358 || _db_warn("Can't restore DB::OUT");
2359 open( STDOUT, ">&SAVEOUT" )
2360 || _db_warn("Can't restore STDOUT");
2362 } ## end if ($pager =~ /^\|/)
2365 # Redirect I/O. STDOUT already safe.
2366 open( OUT, ">&STDOUT" ) # XXX: lost message
2367 || _db_warn("Can't restore DB::OUT");
2370 } ## end unless ($piped = open(OUT,...
2372 # Set up broken-pipe handler if necessary.
2373 $SIG{PIPE} = \&DB::catch
2375 && ( "" eq $SIG{PIPE} || "DEFAULT" eq $SIG{PIPE} );
2378 # Save current filehandle, and put it back.
2379 $obj->selected(scalar( select(OUT) ));
2380 # Don't put it back if pager was a pipe.
2381 if ($cmd !~ /\A\|\|/)
2383 select($obj->selected());
2387 # Trim off the pipe symbols and run the command now.
2388 $cmd =~ s#\A\|+\s*##;
2395 sub _DB__handle_m_command {
2398 if ($cmd =~ s#\Am\s+([\w:]+)\s*\z# #) {
2403 # m expr - set up DB::eval to do the work
2404 if ($cmd =~ s#\Am\b# #) { # Rest gets done by DB::eval()
2405 $onetimeDump = 'methods'; # method output gets used there
2411 sub _DB__at_end_of_every_command {
2414 # At the end of every command:
2417 # Unhook the pipe mechanism now.
2418 if ( $pager =~ /^\|/ ) {
2420 # No error from the child.
2423 # we cannot warn here: the handle is missing --tchrist
2424 close(OUT) || print SAVEOUT "\nCan't close DB::OUT\n";
2426 # most of the $? crud was coping with broken cshisms
2427 # $? is explicitly set to 0, so this never runs.
2429 print SAVEOUT "Pager '$pager' failed: ";
2431 print SAVEOUT "shell returned -1\n";
2434 print SAVEOUT ( $? & 127 )
2435 ? " (SIG#" . ( $? & 127 ) . ")"
2436 : "", ( $? & 128 ) ? " -- core dumped" : "", "\n";
2439 print SAVEOUT "status ", ( $? >> 8 ), "\n";
2443 # Reopen filehandle for our output (if we can) and
2444 # restore STDOUT (if we can).
2445 open( OUT, ">&STDOUT" ) || _db_warn("Can't restore DB::OUT");
2446 open( STDOUT, ">&SAVEOUT" )
2447 || _db_warn("Can't restore STDOUT");
2449 # Turn off pipe exception handler if necessary.
2450 $SIG{PIPE} = "DEFAULT" if $SIG{PIPE} eq \&DB::catch;
2452 # Will stop ignoring SIGPIPE if done like nohup(1)
2453 # does SIGINT but Perl doesn't give us a choice.
2454 } ## end if ($pager =~ /^\|/)
2457 # Non-piped "pager". Just restore STDOUT.
2458 open( OUT, ">&SAVEOUT" ) || _db_warn("Can't restore DB::OUT");
2461 # Let Readline know about the new filehandles.
2462 reset_IN_OUT( \*IN, \*OUT );
2464 # Close filehandle pager was using, restore the normal one
2468 if ($obj->selected() ne "") {
2469 select($obj->selected);
2475 } ## end if ($piped)
2480 sub _DB__handle_watch_expressions
2484 if ( $DB::trace & 2 ) {
2485 for my $n (0 .. $#DB::to_watch) {
2486 $DB::evalarg = $DB::to_watch[$n];
2487 local $DB::onetimeDump; # Tell DB::eval() to not output results
2489 # Fix context DB::eval() wants to return an array, but
2490 # we need a scalar here.
2491 my ($val) = join( "', '", DB::eval(@_) );
2492 $val = ( ( defined $val ) ? "'$val'" : 'undef' );
2495 if ( $val ne $DB::old_watch[$n] ) {
2497 # Yep! Show the difference, and fake an interrupt.
2499 print {$DB::OUT} <<EOP;
2500 Watchpoint $n:\t$DB::to_watch[$n] changed:
2501 old value:\t$DB::old_watch[$n]
2504 $DB::old_watch[$n] = $val;
2505 } ## end if ($val ne $old_watch...
2506 } ## end for my $n (0 ..
2507 } ## end if ($trace & 2)
2514 # 'v' is the value (i.e: method name or subroutine ref).
2515 # 's' is subroutine.
2522 '-' => { t => 'm', v => '_handle_dash_command', },
2523 '.' => { t => 's', v => \&_DB__handle_dot_command, },
2524 '=' => { t => 'm', v => '_handle_equal_sign_command', },
2525 'H' => { t => 'm', v => '_handle_H_command', },
2526 'S' => { t => 'm', v => '_handle_S_command', },
2527 'T' => { t => 'm', v => '_handle_T_command', },
2528 'W' => { t => 'm', v => '_handle_W_command', },
2529 'c' => { t => 's', v => \&_DB__handle_c_command, },
2530 'f' => { t => 's', v => \&_DB__handle_f_command, },
2531 'm' => { t => 's', v => \&_DB__handle_m_command, },
2532 'n' => { t => 'm', v => '_handle_n_command', },
2533 'p' => { t => 'm', v => '_handle_p_command', },
2534 'q' => { t => 'm', v => '_handle_q_command', },
2535 'r' => { t => 'm', v => '_handle_r_command', },
2536 's' => { t => 'm', v => '_handle_s_command', },
2537 'save' => { t => 'm', v => '_handle_save_command', },
2538 'source' => { t => 'm', v => '_handle_source_command', },
2539 't' => { t => 'm', v => '_handle_t_command', },
2540 'w' => { t => 'm', v => '_handle_w_command', },
2541 'x' => { t => 'm', v => '_handle_x_command', },
2542 'y' => { t => 's', v => \&_DB__handle_y_command, },
2543 (map { $_ => { t => 'm', v => '_handle_V_command_and_X_command', }, }
2545 (map { $_ => { t => 'm', v => '_handle_enable_disable_commands', }, }
2546 qw(enable disable)),
2548 { t => 's', v => \&_DB__handle_restart_and_rerun_commands, },
2550 (map { $_ => {t => 'm', v => '_handle_cmd_wrapper_commands' }, }
2551 qw(a A b B e E h i l L M o O v w W)),
2557 # lock the debugger and get the thread id for the prompt
2561 my ($prefix, $after, $infix);
2567 if ($ENV{PERL5DB_THREADED}) {
2568 $tid = eval { "[".threads->tid."]" };
2574 my $obj = DB::Obj->new(
2576 position => \$position,
2579 explicit_stop => \$explicit_stop,
2581 cmd_args => \$cmd_args,
2582 cmd_verb => \$cmd_verb,
2585 selected => \$selected,
2589 $obj->_DB_on_init__initialize_globals(@_);
2591 # Preserve current values of $@, $!, $^E, $,, $/, $\, $^W.
2592 # The code being debugged may have altered them.
2595 # Since DB::DB gets called after every line, we can use caller() to
2596 # figure out where we last were executing. Sneaky, eh? This works because
2597 # caller is returning all the extra information when called from the
2599 local ( $package, $filename, $line ) = caller;
2600 $filename_ini = $filename;
2602 # set up the context for DB::eval, so it can properly execute
2603 # code on behalf of the user. We add the package in so that the
2604 # code is eval'ed in the proper package (not in the debugger!).
2605 local $usercontext = _calc_usercontext($package);
2607 # Create an alias to the active file magical array to simplify
2609 local (*dbline) = $main::{ '_<' . $filename };
2611 # Last line in the program.
2614 # The &-call is here to ascertain the mutability of @_.
2615 &_DB__determine_if_we_should_break;
2617 # Preserve the current stop-or-not, and see if any of the W
2618 # (watch expressions) has changed.
2619 my $was_signal = $signal;
2621 # If we have any watch expressions ...
2622 _DB__handle_watch_expressions($obj);
2624 =head2 C<watchfunction()>
2626 C<watchfunction()> is a function that can be defined by the user; it is a
2627 function which will be run on each entry to C<DB::DB>; it gets the
2628 current package, filename, and line as its parameters.
2630 The watchfunction can do anything it likes; it is executing in the
2631 debugger's context, so it has access to all of the debugger's internal
2632 data structures and functions.
2634 C<watchfunction()> can control the debugger's actions. Any of the following
2635 will cause the debugger to return control to the user's program after
2636 C<watchfunction()> executes:
2642 Returning a false value from the C<watchfunction()> itself.
2646 Altering C<$single> to a false value.
2650 Altering C<$signal> to a false value.
2654 Turning off the C<4> bit in C<$trace> (this also disables the
2655 check for C<watchfunction()>. This can be done with
2663 # If there's a user-defined DB::watchfunction, call it with the
2664 # current package, filename, and line. The function executes in
2666 if ( $trace & 4 ) { # User-installed watch
2668 if watchfunction( $package, $filename, $line )
2671 and not( $trace & ~4 );
2672 } ## end if ($trace & 4)
2674 # Pick up any alteration to $signal in the watchfunction, and
2675 # turn off the signal now.
2676 $was_signal = $signal;
2679 =head2 GETTING READY TO EXECUTE COMMANDS
2681 The debugger decides to take control if single-step mode is on, the
2682 C<t> command was entered, or the user generated a signal. If the program
2683 has fallen off the end, we set things up so that entering further commands
2684 won't cause trouble, and we say that the program is over.
2688 # Make sure that we always print if asked for explicitly regardless
2689 # of $trace_to_depth .
2690 $explicit_stop = ($single || $was_signal);
2692 # Check to see if we should grab control ($single true,
2693 # trace set appropriately, or we got a signal).
2694 if ( $explicit_stop || ( $trace & 1 ) ) {
2695 $obj->_DB__grab_control(@_);
2696 } ## end if ($single || ($trace...
2700 If there's an action to be executed for the line we stopped at, execute it.
2701 If there are any preprompt actions, execute those as well.
2705 # If there's an action, do it now.
2708 # The &-call is here to ascertain the mutability of @_.
2712 # Are we nested another level (e.g., did we evaluate a function
2713 # that had a breakpoint in it at the debugger prompt)?
2714 if ( $single || $was_signal ) {
2716 # Yes, go down a level.
2717 local $level = $level + 1;
2719 # Do any pre-prompt actions.
2720 foreach $evalarg (@$pre) {
2721 # The &-call is here to ascertain the mutability of @_.
2725 # Complain about too much recursion if we passed the limit.
2727 print $OUT $stack_depth . " levels deep in subroutine calls!\n";
2730 # The line we're currently on. Set $incr to -1 to stay here
2731 # until we get a command that tells us to advance.
2733 $incr = -1; # for backward motion.
2735 # Tack preprompt debugger actions ahead of any actual input.
2736 @typeahead = ( @$pretype, @typeahead );
2738 =head2 WHERE ARE WE?
2740 XXX Relocate this section?
2742 The debugger normally shows the line corresponding to the current line of
2743 execution. Sometimes, though, we want to see the next line, or to move elsewhere
2744 in the file. This is done via the C<$incr>, C<$start>, and C<$max> variables.
2746 C<$incr> controls by how many lines the I<current> line should move forward
2747 after a command is executed. If set to -1, this indicates that the I<current>
2748 line shouldn't change.
2750 C<$start> is the I<current> line. It is used for things like knowing where to
2751 move forwards or backwards from when doing an C<L> or C<-> command.
2753 C<$max> tells the debugger where the last line of the current file is. It's
2754 used to terminate loops most often.
2756 =head2 THE COMMAND LOOP
2758 Most of C<DB::DB> is actually a command parsing and dispatch loop. It comes
2765 The outer part of the loop, starting at the C<CMD> label. This loop
2766 reads a command and then executes it.
2770 The inner part of the loop, starting at the C<PIPE> label. This part
2771 is wholly contained inside the C<CMD> block and only executes a command.
2772 Used to handle commands running inside a pager.
2776 So why have two labels to restart the loop? Because sometimes, it's easier to
2777 have a command I<generate> another command and then re-execute the loop to do
2778 the new command. This is faster, but perhaps a bit more convoluted.
2782 # The big command dispatch loop. It keeps running until the
2783 # user yields up control again.
2785 # If we have a terminal for input, and we get something back
2786 # from readline(), keep on processing.
2789 while (_DB__read_next_cmd($tid))
2793 # ... try to execute the input as debugger commands.
2795 # Don't stop running.
2798 # No signal is active.
2801 # Handle continued commands (ending with \):
2802 if ($cmd =~ s/\\\z/\n/) {
2803 $cmd .= DB::readline(" cont: ");
2807 =head4 The null command
2809 A newline entered by itself means I<re-execute the last command>. We grab the
2810 command out of C<$laststep> (where it was recorded previously), and copy it
2811 back into C<$cmd> to be executed below. If there wasn't any previous command,
2812 we'll do nothing below (no command will match). If there was, we also save it
2813 in the command history and fall through to allow the command parsing to pick
2818 # Empty input means repeat the last command.
2822 chomp($cmd); # get rid of the annoying extra newline
2823 if (length($cmd) >= 2) {
2824 push( @hist, $cmd );
2826 push( @truehist, $cmd );
2830 # This is a restart point for commands that didn't arrive
2831 # via direct user input. It allows us to 'redo PIPE' to
2832 # re-execute command processing without reading a new command.
2834 _DB__trim_command_and_return_first_component($obj);
2836 =head3 COMMAND ALIASES
2838 The debugger can create aliases for commands (these are stored in the
2839 C<%alias> hash). Before a command is executed, the command loop looks it up
2840 in the alias hash and substitutes the contents of the alias for the command,
2841 completely replacing it.
2845 # See if there's an alias for the command, and set it up if so.
2846 if ( $alias{$cmd_verb} ) {
2848 # Squelch signal handling; we want to keep control here
2849 # if something goes loco during the alias eval.
2850 local $SIG{__DIE__};
2851 local $SIG{__WARN__};
2853 # This is a command, so we eval it in the DEBUGGER's
2854 # scope! Otherwise, we can't see the special debugger
2855 # variables, or get to the debugger's subs. (Well, we
2856 # _could_, but why make it even more complicated?)
2857 eval "\$cmd =~ $alias{$cmd_verb}";
2860 print $OUT "Couldn't evaluate '$cmd_verb' alias: $@";
2863 _DB__trim_command_and_return_first_component($obj);
2864 } ## end if ($alias{$cmd_verb})
2866 =head3 MAIN-LINE COMMANDS
2868 All of these commands work up to and after the program being debugged has
2873 Quit the debugger. This entails setting the C<$fall_off_end> flag, so we don't
2874 try to execute further, cleaning any restart-related stuff out of the
2875 environment, and executing with the last value of C<$?>.
2879 # All of these commands were remapped in perl 5.8.0;
2880 # we send them off to the secondary dispatcher (see below).
2881 $obj->_handle_special_char_cmd_wrapper_commands;
2882 _DB__trim_command_and_return_first_component($obj);
2884 if (my $cmd_rec = $cmd_lookup{$cmd_verb}) {
2885 my $type = $cmd_rec->{t};
2886 my $val = $cmd_rec->{v};
2890 elsif ($type eq 's') {
2895 =head4 C<t> - trace [n]
2897 Turn tracing on or off. Inverts the appropriate bit in C<$trace> (q.v.).
2898 If level is specified, set C<$trace_to_depth>.
2900 =head4 C<S> - list subroutines matching/not matching a pattern
2902 Walks through C<%sub>, checking to see whether or not to print the name.
2904 =head4 C<X> - list variables in current package
2906 Since the C<V> command actually processes this, just change this to the
2907 appropriate C<V> command and fall through.
2909 =head4 C<V> - list variables
2911 Uses C<dumpvar.pl> to dump out the current values for selected variables.
2913 =head4 C<x> - evaluate and print an expression
2915 Hands the expression off to C<DB::eval>, setting it up to print the value
2916 via C<dumpvar.pl> instead of just printing it directly.
2918 =head4 C<m> - print methods
2920 Just uses C<DB::methods> to determine what methods are available.
2922 =head4 C<f> - switch files
2924 Switch to a different filename.
2926 =head4 C<.> - return to last-executed line.
2928 We set C<$incr> to -1 to indicate that the debugger shouldn't move ahead,
2929 and then we look up the line in the magical C<%dbline> hash.
2931 =head4 C<-> - back one window
2933 We change C<$start> to be one window back; if we go back past the first line,
2934 we set it to be the first line. We set C<$incr> to put us back at the
2935 currently-executing line, and then put a C<l $start +> (list one window from
2936 C<$start>) in C<$cmd> to be executed later.
2938 =head3 PRE-580 COMMANDS VS. NEW COMMANDS: C<a, A, b, B, h, l, L, M, o, O, P, v, w, W, E<lt>, E<lt>E<lt>, E<0x7B>, E<0x7B>E<0x7B>>
2940 In Perl 5.8.0, a realignment of the commands was done to fix up a number of
2941 problems, most notably that the default case of several commands destroying
2942 the user's work in setting watchpoints, actions, etc. We wanted, however, to
2943 retain the old commands for those who were used to using them or who preferred
2944 them. At this point, we check for the new commands and call C<cmd_wrapper> to
2945 deal with them instead of processing them in-line.
2947 =head4 C<y> - List lexicals in higher scope
2949 Uses C<PadWalker> to find the lexicals supplied as arguments in a scope
2950 above the current one and then displays then using C<dumpvar.pl>.
2952 =head3 COMMANDS NOT WORKING AFTER PROGRAM ENDS
2954 All of the commands below this point don't work after the program being
2955 debugged has ended. All of them check to see if the program has ended; this
2956 allows the commands to be relocated without worrying about a 'line of
2957 demarcation' above which commands can be entered anytime, and below which
2960 =head4 C<n> - single step, but don't trace down into subs
2962 Done by setting C<$single> to 2, which forces subs to execute straight through
2963 when entered (see C<DB::sub>). We also save the C<n> command in C<$laststep>,
2964 so a null command knows what to re-execute.
2966 =head4 C<s> - single-step, entering subs
2968 Sets C<$single> to 1, which causes C<DB::sub> to continue tracing inside
2969 subs. Also saves C<s> as C<$lastcmd>.
2971 =head4 C<c> - run continuously, setting an optional breakpoint
2973 Most of the code for this command is taken up with locating the optional
2974 breakpoint, which is either a subroutine name or a line number. We set
2975 the appropriate one-time-break in C<@dbline> and then turn off single-stepping
2976 in this and all call levels above this one.
2978 =head4 C<r> - return from a subroutine
2980 For C<r> to work properly, the debugger has to stop execution again
2981 immediately after the return is executed. This is done by forcing
2982 single-stepping to be on in the call level above the current one. If
2983 we are printing return values when a C<r> is executed, set C<$doret>
2984 appropriately, and force us out of the command loop.
2986 =head4 C<T> - stack trace
2988 Just calls C<DB::print_trace>.
2990 =head4 C<w> - List window around current line.
2992 Just calls C<DB::cmd_w>.
2994 =head4 C<W> - watch-expression processing.
2996 Just calls C<DB::cmd_W>.
2998 =head4 C</> - search forward for a string in the source
3000 We take the argument and treat it as a pattern. If it turns out to be a
3001 bad one, we return the error we got from trying to C<eval> it and exit.
3002 If not, we create some code to do the search and C<eval> it so it can't
3007 _DB__handle_forward_slash_command($obj);
3009 =head4 C<?> - search backward for a string in the source
3011 Same as for C</>, except the loop runs backwards.
3015 _DB__handle_question_mark_command($obj);
3017 =head4 C<$rc> - Recall command
3019 Manages the commands in C<@hist> (which is created if C<Term::ReadLine> reports
3020 that the terminal supports history). It finds the command required, puts it
3021 into C<$cmd>, and redoes the loop to execute it.
3025 # $rc - recall command.
3026 $obj->_handle_rc_recall_command;
3028 =head4 C<$sh$sh> - C<system()> command
3030 Calls the C<_db_system()> to handle the command. This keeps the C<STDIN> and
3031 C<STDOUT> from getting messed up.
3035 $obj->_handle_sh_command;
3037 =head4 C<$rc I<pattern> $rc> - Search command history
3039 Another command to manipulate C<@hist>: this one searches it with a pattern.
3040 If a command is found, it is placed in C<$cmd> and executed via C<redo>.
3044 $obj->_handle_rc_search_history_command;
3046 =head4 C<$sh> - Invoke a shell
3048 Uses C<_db_system()> to invoke a shell.
3052 =head4 C<$sh I<command>> - Force execution of a command in a shell
3054 Like the above, but the command is passed to the shell. Again, we use
3055 C<_db_system()> to avoid problems with C<STDIN> and C<STDOUT>.
3057 =head4 C<H> - display commands in history
3059 Prints the contents of C<@hist> (if any).
3061 =head4 C<man, doc, perldoc> - look up documentation
3063 Just calls C<runman()> to print the appropriate document.
3067 $obj->_handle_doc_command;
3071 Builds a C<print EXPR> expression in the C<$cmd>; this will get executed at
3072 the bottom of the loop.
3074 =head4 C<=> - define command alias
3076 Manipulates C<%alias> to add or list command aliases.
3078 =head4 C<source> - read commands from a file.
3080 Opens a lexical filehandle and stacks it on C<@cmdfhs>; C<DB::readline> will
3083 =head4 C<enable> C<disable> - enable or disable breakpoints
3085 This enables or disables breakpoints.
3087 =head4 C<save> - send current history to a file
3089 Takes the complete history, (not the shrunken version you see with C<H>),
3090 and saves it to the given filename, so it can be replayed using C<source>.
3092 Note that all C<^(save|source)>'s are commented out with a view to minimise recursion.
3094 =head4 C<R> - restart
3096 Restart the debugger session.
3098 =head4 C<rerun> - rerun the current session
3100 Return to any given position in the B<true>-history list
3102 =head4 C<|, ||> - pipe output through the pager.
3104 For C<|>, we save C<OUT> (the debugger's output filehandle) and C<STDOUT>
3105 (the program's standard output). For C<||>, we only save C<OUT>. We open a
3106 pipe to the pager (restoring the output filehandles if this fails). If this
3107 is the C<|> command, we also set up a C<SIGPIPE> handler which will simply
3108 set C<$signal>, sending us back into the debugger.
3110 We then trim off the pipe symbols and C<redo> the command loop at the
3111 C<PIPE> label, causing us to evaluate the command in C<$cmd> without
3116 # || - run command in the pager, with output to DB::OUT.
3117 _DB__handle_run_command_in_pager_command($obj);
3119 =head3 END OF COMMAND PARSING
3121 Anything left in C<$cmd> at this point is a Perl expression that we want to
3122 evaluate. We'll always evaluate in the user's context, and fully qualify
3123 any variables we might want to address in the C<DB> package.
3129 # trace an expression
3130 $cmd =~ s/^t\s/\$DB::trace |= 1;\n/;
3132 # Make sure the flag that says "the debugger's running" is
3133 # still on, to make sure we get control again.
3134 $evalarg = "\$^D = \$^D | \$DB::db_stop;\n$cmd";
3136 # Run *our* eval that executes in the caller's context.
3137 # The &-call is here to ascertain the mutability of @_.
3140 # Turn off the one-time-dump stuff now.
3142 $onetimeDump = undef;
3143 $onetimedumpDepth = undef;
3145 elsif ( $term_pid == $$ ) {
3146 eval { # May run under miniperl, when not available...
3151 # XXX If this is the master pid, print a newline.
3154 } ## end while (($term || &setterm...
3156 =head3 POST-COMMAND PROCESSING
3158 After each command, we check to see if the command output was piped anywhere.
3159 If so, we go through the necessary code to unhook the pipe and go back to
3160 our standard filehandles for input and output.
3165 _DB__at_end_of_every_command($obj);
3168 =head3 COMMAND LOOP TERMINATION
3170 When commands have finished executing, we come here. If the user closed the
3171 input filehandle, we turn on C<$fall_off_end> to emulate a C<q> command. We
3172 evaluate any post-prompt items. We restore C<$@>, C<$!>, C<$^E>, C<$,>, C<$/>,
3173 C<$\>, and C<$^W>, and return a null list as expected by the Perl interpreter.
3174 The interpreter will then execute the next line and then return control to us
3179 # No more commands? Quit.
3180 $fall_off_end = 1 unless defined $cmd; # Emulate 'q' on EOF
3182 # Evaluate post-prompt commands.
3183 foreach $evalarg (@$post) {
3184 # The &-call is here to ascertain the mutability of @_.
3187 } # if ($single || $signal)
3189 # Put the user's globals back where you found them.
3190 ( $@, $!, $^E, $,, $/, $\, $^W ) = @saved;
3194 # Because DB::Obj is used above,
3196 # my $obj = DB::Obj->new(
3198 # The following package declaration must come before that,
3199 # or else runtime errors will occur with
3201 # PERLDB_OPTS="autotrace nonstop"
3211 my $self = bless {}, $class;
3219 my ($self, $args) = @_;
3221 %{$self} = (%$self, %$args);
3228 foreach my $slot_name (qw(
3229 after explicit_stop infix pat piped position prefix selected cmd_verb
3232 my $slot = $slot_name;
3237 ${ $self->{$slot} } = shift;
3240 return ${ $self->{$slot} };
3243 *{"append_to_$slot"} = sub {
3247 return $self->$slot($self->$slot . $s);
3252 sub _DB_on_init__initialize_globals
3256 # Check for whether we should be running continuously or not.
3257 # _After_ the perl program is compiled, $single is set to 1:
3258 if ( $single and not $second_time++ ) {
3260 # Options say run non-stop. Run until we get an interrupt.
3261 if ($runnonstop) { # Disable until signal
3262 # If there's any call stack in place, turn off single
3263 # stepping into subs throughout the stack.
3264 for my $i (0 .. $stack_depth) {
3268 # And we are now no longer in single-step mode.
3271 # If we simply returned at this point, we wouldn't get
3272 # the trace info. Fall on through.
3274 } ## end if ($runnonstop)
3276 elsif ($ImmediateStop) {
3278 # We are supposed to stop here; XXX probably a break.
3279 $ImmediateStop = 0; # We've processed it; turn it off
3280 $signal = 1; # Simulate an interrupt to force
3281 # us into the command loop
3283 } ## end if ($single and not $second_time...
3285 # If we're in single-step mode, or an interrupt (real or fake)
3286 # has occurred, turn off non-stop mode.
3287 $runnonstop = 0 if $single or $signal;
3292 sub _my_print_lineinfo
3294 my ($self, $i, $incr_pos) = @_;
3297 # Print it indented if tracing is on.
3298 DB::print_lineinfo( ' ' x $stack_depth,
3299 "$i:\t$DB::dbline[$i]" . $self->after );
3302 DB::depth_print_lineinfo($self->explicit_stop, $incr_pos);
3307 return $DB::dbline[$line];
3311 my ($self, $letter) = @_;
3313 return ($DB::cmd eq $letter);
3316 sub _DB__grab_control
3320 # Yes, grab control.
3321 if ($slave_editor) {
3323 # Tell the editor to update its position.
3324 $self->position("\032\032${DB::filename}:$line:0\n");
3325 DB::print_lineinfo($self->position());
3330 Special check: if we're in package C<DB::fake>, we've gone through the
3331 C<END> block at least once. We set up everything so that we can continue
3332 to enter commands and have a valid context to be in.
3336 elsif ( $DB::package eq 'DB::fake' ) {
3338 # Fallen off the end already.
3343 DB::print_help(<<EOP);
3344 Debugged program terminated. Use B<q> to quit or B<R> to restart,
3345 use B<o> I<inhibit_exit> to avoid stopping after program termination,
3346 B<h q>, B<h R> or B<h o> to get additional info.
3349 # Set the DB::eval context appropriately.
3350 # At program termination disable any user actions.
3351 $DB::action = undef;
3353 $DB::package = 'main';
3354 $DB::usercontext = DB::_calc_usercontext($DB::package);
3355 } ## end elsif ($package eq 'DB::fake')
3359 If the program hasn't finished executing, we scan forward to the
3360 next executable line, print that out, build the prompt from the file and line
3361 number information, and print that.
3368 # Still somewhere in the midst of execution. Set up the
3370 $DB::sub =~ s/\'/::/; # Swap Perl 4 package separators (') to
3371 # Perl 5 ones (sorry, we don't print Klingon
3374 $self->prefix($DB::sub =~ /::/ ? "" : ($DB::package . '::'));
3375 $self->append_to_prefix( "$DB::sub(${DB::filename}:" );
3376 $self->after( $self->_curr_line =~ /\n$/ ? '' : "\n" );
3378 # Break up the prompt if it's really long.
3379 if ( length($self->prefix()) > 30 ) {
3380 $self->position($self->prefix . "$line):\n$line:\t" . $self->_curr_line . $self->after);
3382 $self->infix(":\t");
3385 $self->infix("):\t");
3387 $self->prefix . $line. $self->infix
3388 . $self->_curr_line . $self->after
3392 # Print current line info, indenting if necessary.
3393 $self->_my_print_lineinfo($line, $self->position);
3396 my $line_i = sub { return $DB::dbline[$i]; };
3398 # Scan forward, stopping at either the end or the next
3400 for ( $i = $line + 1 ; $i <= $DB::max && $line_i->() == 0 ; ++$i )
3403 # Drop out on null statements, block closers, and comments.
3404 last if $line_i->() =~ /^\s*[\;\}\#\n]/;
3406 # Drop out if the user interrupted us.
3409 # Append a newline if the line doesn't have one. Can happen
3410 # in eval'ed text, for instance.
3411 $self->after( $line_i->() =~ /\n$/ ? '' : "\n" );
3413 # Next executable line.
3414 my $incr_pos = $self->prefix . $i . $self->infix . $line_i->()
3416 $self->append_to_position($incr_pos);
3417 $self->_my_print_lineinfo($i, $incr_pos);
3418 } ## end for ($i = $line + 1 ; $i...
3419 } ## end else [ if ($slave_editor)
3424 sub _handle_t_command {
3427 my $levels = $self->cmd_args();
3429 if ((!length($levels)) or ($levels !~ /\D/)) {
3432 $DB::trace_to_depth = $levels ? $stack_depth + $levels : 1E9;
3433 print {$OUT} "Trace = "
3435 ? ( $levels ? "on (to level $DB::trace_to_depth)" : "on" )
3444 sub _handle_S_command {
3447 if (my ($print_all_subs, $should_reverse, $Spatt)
3448 = $self->cmd_args =~ /\A((!)?(.+))?\z/) {
3449 # $Spatt is the pattern (if any) to use.
3451 my $Srev = defined $should_reverse;
3452 # No args - print all subs.
3453 my $Snocheck = !defined $print_all_subs;
3455 # Need to make these sane here.
3459 # Search through the debugger's magical hash of subs.
3460 # If $nocheck is true, just print the sub name.
3461 # Otherwise, check it against the pattern. We then use
3462 # the XOR trick to reverse the condition as required.
3463 foreach $subname ( sort( keys %sub ) ) {
3464 if ( $Snocheck or $Srev ^ ( $subname =~ /$Spatt/ ) ) {
3465 print $OUT $subname, "\n";
3474 sub _handle_V_command_and_X_command {
3477 $DB::cmd =~ s/^X\b/V $DB::package/;
3479 # Bare V commands get the currently-being-debugged package
3481 if ($self->_is_full('V')) {
3482 $DB::cmd = "V $DB::package";
3485 # V - show variables in package.
3486 if (my ($new_packname, $new_vars_str) =
3487 $DB::cmd =~ /\AV\b\s*(\S+)\s*(.*)/) {
3489 # Save the currently selected filehandle and
3490 # force output to debugger's filehandle (dumpvar
3491 # just does "print" for output).
3492 my $savout = select($OUT);
3494 # Grab package name and variables to dump.
3495 $packname = $new_packname;
3496 my @vars = split( ' ', $new_vars_str );
3498 # If main::dumpvar isn't here, get it.
3499 do 'dumpvar.pl' || die $@ unless defined &main::dumpvar;
3500 if ( defined &main::dumpvar ) {
3502 # We got it. Turn off subroutine entry/exit messages
3503 # for the moment, along with return values.
3507 # must detect sigpipe failures - not catching
3508 # then will cause the debugger to die.
3512 defined $option{dumpDepth}
3513 ? $option{dumpDepth}
3514 : -1, # assume -1 unless specified
3519 # The die doesn't need to include the $@, because
3520 # it will automatically get propagated for us.
3522 die unless $@ =~ /dumpvar print failed/;
3524 } ## end if (defined &main::dumpvar)
3527 # Couldn't load dumpvar.
3528 print $OUT "dumpvar.pl not available.\n";
3531 # Restore the output filehandle, and go round again.
3539 sub _handle_dash_command {
3542 if ($self->_is_full('-')) {
3544 # back up by a window; go to 1 if back too far.
3545 $start -= $incr + $window + 1;
3546 $start = 1 if $start <= 0;
3547 $incr = $window - 1;
3549 # Generate and execute a "l +" command (handled below).
3550 $DB::cmd = 'l ' . ($start) . '+';
3556 sub _n_or_s_commands_generic {
3557 my ($self, $new_val) = @_;
3559 next CMD if DB::_DB__is_finished();
3561 # Single step, but don't enter subs.
3564 # Save for empty command (repeat last).
3565 $laststep = $DB::cmd;
3570 my ($self, $letter, $new_val) = @_;
3572 if ($self->_is_full($letter)) {
3573 $self->_n_or_s_commands_generic($new_val);
3576 $self->_n_or_s_and_arg_commands_generic($letter, $new_val);
3582 sub _handle_n_command {
3585 return $self->_n_or_s('n', 2);
3588 sub _handle_s_command {
3591 return $self->_n_or_s('s', 1);
3594 sub _handle_r_command {
3597 # r - return from the current subroutine.
3598 if ($self->_is_full('r')) {
3600 # Can't do anything if the program's over.
3601 next CMD if DB::_DB__is_finished();
3603 # Turn on stack trace.
3604 $stack[$stack_depth] |= 1;
3606 # Print return value unless the stack is empty.
3607 $doret = $option{PrintRet} ? $stack_depth - 1 : -2;
3614 sub _handle_T_command {
3617 if ($self->_is_full('T')) {
3618 DB::print_trace( $OUT, 1 ); # skip DB
3625 sub _handle_w_command {
3628 DB::cmd_w( 'w', $self->cmd_args() );
3634 sub _handle_W_command {
3637 if (my $arg = $self->cmd_args) {
3638 DB::cmd_W( 'W', $arg );
3645 sub _handle_rc_recall_command {
3648 # $rc - recall command.
3649 if (my ($minus, $arg) = $DB::cmd =~ m#\A$rc+\s*(-)?(\d+)?\z#) {
3651 # No arguments, take one thing off history.
3652 pop(@hist) if length($DB::cmd) > 1;
3654 # Relative (- found)?
3655 # Y - index back from most recent (by 1 if bare minus)
3656 # N - go to that particular command slot or the last
3657 # thing if nothing following.
3660 scalar($minus ? ( $#hist - ( $arg || 1 ) ) : ( $arg || $#hist ))
3663 # Pick out the command desired.
3664 $DB::cmd = $hist[$self->cmd_verb];
3666 # Print the command to be executed and restart the loop
3667 # with that command in the buffer.
3668 print {$OUT} $DB::cmd, "\n";
3675 sub _handle_rc_search_history_command {
3678 # $rc pattern $rc - find a command in the history.
3679 if (my ($arg) = $DB::cmd =~ /\A$rc([^$rc].*)\z/) {
3681 # Create the pattern to use.
3685 # Toss off last entry if length is >1 (and it always is).
3686 pop(@hist) if length($DB::cmd) > 1;
3690 # Look backward through the history.
3692 for ( $i = $#hist ; $i ; --$i ) {
3693 # Stop if we find it.
3694 last SEARCH_HIST if $hist[$i] =~ /$pat/;
3700 print $OUT "No such command!\n\n";
3704 # Found it. Put it in the buffer, print it, and process it.
3705 $DB::cmd = $hist[$i];
3706 print $OUT $DB::cmd, "\n";
3713 sub _handle_H_command {
3716 if ($self->cmd_args =~ m#\A\*#) {
3717 @hist = @truehist = ();
3718 print $OUT "History cleansed\n";
3722 if (my ($num) = $self->cmd_args =~ /\A(?:-(\d+))?/) {
3724 # Anything other than negative numbers is ignored by
3725 # the (incorrect) pattern, so this test does nothing.
3726 $end = $num ? ( $#hist - $num ) : 0;
3728 # Set to the minimum if less than zero.
3729 $hist = 0 if $hist < 0;
3731 # Start at the end of the array.
3732 # Stay in while we're still above the ending value.
3733 # Tick back by one each time around the loop.
3736 for ( $i = $#hist ; $i > $end ; $i-- ) {
3738 # Print the command unless it has no arguments.
3739 print $OUT "$i: ", $hist[$i], "\n"
3740 unless $hist[$i] =~ /^.?$/;
3749 sub _handle_doc_command {
3752 # man, perldoc, doc - show manual pages.
3754 = $DB::cmd =~ /\A(?:man|(?:perl)?doc)\b(?:\s+([^(]*))?\z/) {
3755 DB::runman($man_page);
3762 sub _handle_p_command {
3765 my $print_cmd = 'print {$DB::OUT} ';
3766 # p - print (no args): print $_.
3767 if ($self->_is_full('p')) {
3768 $DB::cmd = $print_cmd . '$_';
3771 # p - print the given expression.
3772 $DB::cmd =~ s/\Ap\b/$print_cmd /;
3778 sub _handle_equal_sign_command {
3781 if ($DB::cmd =~ s/\A=\s*//) {
3783 if ( length $DB::cmd == 0 ) {
3785 # No args, get current aliases.
3786 @keys = sort keys %alias;
3788 elsif ( my ( $k, $v ) = ( $DB::cmd =~ /^(\S+)\s+(\S.*)/ ) ) {
3790 # Creating a new alias. $k is alias name, $v is
3793 # can't use $_ or kill //g state
3794 for my $x ( $k, $v ) {
3796 # Escape "alarm" characters.
3800 # Substitute key for value, using alarm chars
3801 # as separators (which is why we escaped them in
3803 $alias{$k} = "s\a$k\a$v\a";
3805 # Turn off standard warn and die behavior.
3806 local $SIG{__DIE__};
3807 local $SIG{__WARN__};
3810 unless ( eval "sub { s\a$k\a$v\a }; 1" ) {
3812 # Nope. Bad alias. Say so and get out.
3813 print $OUT "Can't alias $k to $v: $@\n";
3818 # We'll only list the new one.
3820 } ## end elsif (my ($k, $v) = ($DB::cmd...
3822 # The argument is the alias to list.
3830 # Messy metaquoting: Trim the substitution code off.
3831 # We use control-G as the delimiter because it's not
3832 # likely to appear in the alias.
3833 if ( ( my $v = $alias{$k} ) =~ s
\as\a$k\a(.*)\a$
\a1
\a ) {
3836 print $OUT "$k\t= $1\n";
3838 elsif ( defined $alias{$k} ) {
3840 # Couldn't trim it off; just print the alias code.
3841 print $OUT "$k\t$alias{$k}\n";
3846 print "No alias for $k\n";
3848 } ## end for my $k (@keys)
3855 sub _handle_source_command {
3858 # source - read commands from a file (or pipe!) and execute.
3859 if (my $sourced_fn = $self->cmd_args) {
3860 if ( open my $fh, $sourced_fn ) {
3862 # Opened OK; stick it in the list of file handles.
3868 DB::_db_warn("Can't execute '$sourced_fn': $!\n");
3876 sub _handle_enable_disable_commands {
3879 my $which_cmd = $self->cmd_verb;
3880 my $position = $self->cmd_args;
3882 if ($position !~ /\s/) {
3883 my ($fn, $line_num);
3884 if ($position =~ m{\A\d+\z})
3886 $fn = $DB::filename;
3887 $line_num = $position;
3889 elsif (my ($new_fn, $new_line_num)
3890 = $position =~ m{\A(.*):(\d+)\z}) {
3891 ($fn, $line_num) = ($new_fn, $new_line_num);
3895 DB::_db_warn("Wrong spec for enable/disable argument.\n");
3899 if (DB::_has_breakpoint_data_ref($fn, $line_num)) {
3900 DB::_set_breakpoint_enabled_status($fn, $line_num,
3901 ($which_cmd eq 'enable' ? 1 : '')
3905 DB::_db_warn("No breakpoint set at ${fn}:${line_num}\n");
3915 sub _handle_save_command {
3918 if (my $new_fn = $self->cmd_args) {
3919 my $filename = $new_fn || '.perl5dbrc'; # default?
3920 if ( open my $fh, '>', $filename ) {
3922 # chomp to remove extraneous newlines from source'd files
3923 chomp( my @truelist =
3924 map { m/\A\s*(save|source)/ ? "#$_" : $_ }
3926 print {$fh} join( "\n", @truelist );
3927 print "commands saved in $filename\n";
3930 DB::_db_warn("Can't save debugger commands in '$new_fn': $!\n");
3938 sub _n_or_s_and_arg_commands_generic {
3939 my ($self, $letter, $new_val) = @_;
3941 # s - single-step. Remember the last command was 's'.
3942 if ($DB::cmd =~ s#\A\Q$letter\E\s#\$DB::single = $new_val;\n#) {
3943 $laststep = $letter;
3949 sub _handle_sh_command {
3952 # $sh$sh - run a shell command (if it's all ASCII).
3953 # Can't run shell commands with Unicode in the debugger, hmm.
3954 my $my_cmd = $DB::cmd;
3955 if ($my_cmd =~ m#\A$sh#gms) {
3957 if ($my_cmd =~ m#\G\z#cgms) {
3958 # Run the user's shell. If none defined, run Bourne.
3959 # We resume execution when the shell terminates.
3960 DB::_db_system( $ENV{SHELL} || "/bin/sh" );
3963 elsif ($my_cmd =~ m#\G$sh\s*(.*)#cgms) {
3968 elsif ($my_cmd =~ m#\G\s*(.*)#cgms) {
3969 DB::_db_system( $ENV{SHELL} || "/bin/sh", "-c", $1 );
3975 sub _handle_x_command {
3978 if ($DB::cmd =~ s#\Ax\b# #) { # Remainder gets done by DB::eval()
3979 $onetimeDump = 'dump'; # main::dumpvar shows the output
3981 # handle special "x 3 blah" syntax XXX propagate
3982 # doc back to special variables.
3983 if ( $DB::cmd =~ s#\A\s*(\d+)(?=\s)# #) {
3984 $onetimedumpDepth = $1;
3991 sub _handle_q_command {
3994 if ($self->_is_full('q')) {
4003 sub _handle_cmd_wrapper_commands {
4006 DB::cmd_wrapper( $self->cmd_verb, $self->cmd_args, $line );
4010 sub _handle_special_char_cmd_wrapper_commands {
4013 # All of these commands were remapped in perl 5.8.0;
4014 # we send them off to the secondary dispatcher (see below).
4015 if (my ($cmd_letter, $my_arg) = $DB::cmd =~ /\A([<>\{]{1,2})\s*(.*)/so) {
4016 DB::cmd_wrapper( $cmd_letter, $my_arg, $line );
4027 # The following code may be executed now:
4032 C<sub> is called whenever a subroutine call happens in the program being
4033 debugged. The variable C<$DB::sub> contains the name of the subroutine
4036 The core function of this subroutine is to actually call the sub in the proper
4037 context, capturing its output. This of course causes C<DB::DB> to get called
4038 again, repeating until the subroutine ends and returns control to C<DB::sub>
4039 again. Once control returns, C<DB::sub> figures out whether or not to dump the
4040 return value, and returns its captured copy of the return value as its own
4041 return value. The value then feeds back into the program being debugged as if
4042 C<DB::sub> hadn't been there at all.
4044 C<sub> does all the work of printing the subroutine entry and exit messages
4045 enabled by setting C<$frame>. It notes what sub the autoloader got called for,
4046 and also prints the return value if needed (for the C<r> command and if
4047 the 16 bit is set in C<$frame>).
4049 It also tracks the subroutine call depth by saving the current setting of
4050 C<$single> in the C<@stack> package global; if this exceeds the value in
4051 C<$deep>, C<sub> automatically turns on printing of the current depth by
4052 setting the C<4> bit in C<$single>. In any case, it keeps the current setting
4053 of stop/don't stop on entry to subs set as it currently is set.
4055 =head3 C<caller()> support
4057 If C<caller()> is called from the package C<DB>, it provides some
4058 additional data, in the following order:
4064 The package name the sub was in
4066 =item * C<$filename>
4068 The filename it was defined in
4072 The line number it was defined on
4074 =item * C<$subroutine>
4076 The subroutine name; C<(eval)> if an C<eval>().
4080 1 if it has arguments, 0 if not
4082 =item * C<$wantarray>
4084 1 if array context, 0 if scalar context
4086 =item * C<$evaltext>
4088 The C<eval>() text, if any (undefined for C<eval BLOCK>)
4090 =item * C<$is_require>
4092 frame was created by a C<use> or C<require> statement
4096 pragma information; subject to change between versions
4100 pragma information; subject to change between versions
4102 =item * C<@DB::args>
4104 arguments with which the subroutine was invoked
4112 # We need to fully qualify the name ("DB::sub") to make "use strict;"
4113 # happy. -- Shlomi Fish
4115 sub _indent_print_line_info {
4116 my ($offset, $str) = @_;
4118 print_lineinfo( ' ' x ($stack_depth - $offset), $str);
4123 sub _print_frame_message {
4127 if ($frame & 4) { # Extended frame entry message
4128 _indent_print_line_info(-1, "in ");
4130 # Why -1? But it works! :-(
4131 # Because print_trace will call add 1 to it and then call
4132 # dump_trace; this results in our skipping -1+1 = 0 stack frames
4135 # Now it's 0 because we extracted a function.
4136 print_trace( $LINEINFO, 0, 1, 1, "$sub$al" );
4139 _indent_print_line_info(-1, "entering $sub$al\n" );
4147 # lock ourselves under threads
4150 # Whether or not the autoloader was running, a scalar to put the
4151 # sub's return value in (if needed), and an array to put the sub's
4152 # return value in (if needed).
4153 my ( $al, $ret, @ret ) = "";
4154 if ($sub eq 'threads::new' && $ENV{PERL5DB_THREADED}) {
4155 print "creating new thread\n";
4158 # If the last ten characters are '::AUTOLOAD', note we've traced
4159 # into AUTOLOAD for $sub.
4160 if ( length($sub) > 10 && substr( $sub, -10, 10 ) eq '::AUTOLOAD' ) {
4162 $al = " for $$sub" if defined $$sub;
4165 # We stack the stack pointer and then increment it to protect us
4166 # from a situation that might unwind a whole bunch of call frames
4167 # at once. Localizing the stack pointer means that it will automatically
4168 # unwind the same amount when multiple stack frames are unwound.
4169 local $stack_depth = $stack_depth + 1; # Protect from non-local exits
4172 $#stack = $stack_depth;
4174 # Save current single-step setting.
4175 $stack[-1] = $single;
4177 # Turn off all flags except single-stepping.
4180 # If we've gotten really deeply recursed, turn on the flag that will
4181 # make us stop with the 'deep recursion' message.
4182 $single |= 4 if $stack_depth == $deep;
4184 # If frame messages are on ...
4186 _print_frame_message($al);
4187 # standard frame entry message
4189 my $print_exit_msg = sub {
4190 # Check for exit trace messages...
4193 if ($frame & 4) # Extended exit message
4195 _indent_print_line_info(0, "out ");
4196 print_trace( $LINEINFO, 0, 1, 1, "$sub$al" );
4200 _indent_print_line_info(0, "exited $sub$al\n" );
4206 # Determine the sub's return type, and capture appropriately.
4209 # Called in array context. call sub and capture output.
4210 # DB::DB will recursively get control again if appropriate; we'll come
4211 # back here when the sub is finished.
4217 # Pop the single-step value back off the stack.
4218 $single |= $stack[ $stack_depth-- ];
4220 $print_exit_msg->();
4222 # Print the return info if we need to.
4223 if ( $doret eq $stack_depth or $frame & 16 ) {
4225 # Turn off output record separator.
4227 my $fh = ( $doret eq $stack_depth ? $OUT : $LINEINFO );
4229 # Indent if we're printing because of $frame tracing.
4232 print {$fh} ' ' x $stack_depth;
4235 # Print the return value.
4236 print {$fh} "list context return from $sub:\n";
4237 dumpit( $fh, \@ret );
4239 # And don't print it again.
4241 } ## end if ($doret eq $stack_depth...
4242 # And we have to return the return value now.
4244 } ## end if (wantarray)
4248 if ( defined wantarray ) {
4250 # Save the value if it's wanted at all.
4255 # Void return, explicitly.
4260 # Pop the single-step value off the stack.
4261 $single |= $stack[ $stack_depth-- ];
4263 # If we're doing exit messages...
4264 $print_exit_msg->();
4266 # If we are supposed to show the return value... same as before.
4267 if ( $doret eq $stack_depth or $frame & 16 and defined wantarray ) {
4269 my $fh = ( $doret eq $stack_depth ? $OUT : $LINEINFO );
4270 print $fh ( ' ' x $stack_depth ) if $frame & 16;
4273 ? "scalar context return from $sub: "
4274 : "void context return from $sub\n"
4276 dumpit( $fh, $ret ) if defined wantarray;
4278 } ## end if ($doret eq $stack_depth...
4280 # Return the appropriate scalar value.
4282 } ## end else [ if (wantarray)
4289 # lock ourselves under threads
4292 # Whether or not the autoloader was running, a scalar to put the
4293 # sub's return value in (if needed), and an array to put the sub's
4294 # return value in (if needed).
4295 my ( $al, $ret, @ret ) = "";
4296 if ($sub =~ /^threads::new$/ && $ENV{PERL5DB_THREADED}) {
4297 print "creating new thread\n";
4300 # If the last ten characters are C'::AUTOLOAD', note we've traced
4301 # into AUTOLOAD for $sub.
4302 if ( length($sub) > 10 && substr( $sub, -10, 10 ) eq '::AUTOLOAD' ) {
4306 # We stack the stack pointer and then increment it to protect us
4307 # from a situation that might unwind a whole bunch of call frames
4308 # at once. Localizing the stack pointer means that it will automatically
4309 # unwind the same amount when multiple stack frames are unwound.
4310 local $stack_depth = $stack_depth + 1; # Protect from non-local exits
4313 $#stack = $stack_depth;
4315 # Save current single-step setting.
4316 $stack[-1] = $single;
4318 # Turn off all flags except single-stepping.
4319 # Use local so the single-step value is popped back off the
4321 local $single = $single & 1;
4323 # If we've gotten really deeply recursed, turn on the flag that will
4324 # make us stop with the 'deep recursion' message.
4325 $single |= 4 if $stack_depth == $deep;
4327 # If frame messages are on ...
4328 _print_frame_message($al);
4330 # call the original lvalue sub.
4334 # Abstracting common code from multiple places elsewhere:
4335 sub depth_print_lineinfo {
4336 my $always_print = shift;
4338 print_lineinfo( @_ ) if ($always_print or $stack_depth < $trace_to_depth);
4341 =head1 EXTENDED COMMAND HANDLING AND THE COMMAND API
4343 In Perl 5.8.0, there was a major realignment of the commands and what they did,
4344 Most of the changes were to systematize the command structure and to eliminate
4345 commands that threw away user input without checking.
4347 The following sections describe the code added to make it easy to support
4348 multiple command sets with conflicting command names. This section is a start
4349 at unifying all command processing to make it simpler to develop commands.
4351 Note that all the cmd_[a-zA-Z] subroutines require the command name, a line
4352 number, and C<$dbline> (the current line) as arguments.
4354 Support functions in this section which have multiple modes of failure C<die>
4355 on error; the rest simply return a false value.
4357 The user-interface functions (all of the C<cmd_*> functions) just output
4362 The C<%set> hash defines the mapping from command letter to subroutine
4365 C<%set> is a two-level hash, indexed by set name and then by command name.
4366 Note that trying to set the CommandSet to C<foobar> simply results in the
4367 5.8.0 command set being used, since there's no top-level entry for C<foobar>.
4376 'A' => 'pre580_null',
4378 'B' => 'pre580_null',
4379 'd' => 'pre580_null',
4382 'M' => 'pre580_null',
4384 'o' => 'pre580_null',
4390 '<' => 'pre590_prepost',
4391 '<<' => 'pre590_prepost',
4392 '>' => 'pre590_prepost',
4393 '>>' => 'pre590_prepost',
4394 '{' => 'pre590_prepost',
4395 '{{' => 'pre590_prepost',
4399 my %breakpoints_data;
4401 sub _has_breakpoint_data_ref {
4402 my ($filename, $line) = @_;
4405 exists( $breakpoints_data{$filename} )
4407 exists( $breakpoints_data{$filename}{$line} )
4411 sub _get_breakpoint_data_ref {
4412 my ($filename, $line) = @_;
4414 return ($breakpoints_data{$filename}{$line} ||= +{});
4417 sub _delete_breakpoint_data_ref {
4418 my ($filename, $line) = @_;
4420 delete($breakpoints_data{$filename}{$line});
4421 if (! scalar(keys( %{$breakpoints_data{$filename}} )) ) {
4422 delete($breakpoints_data{$filename});
4428 sub _set_breakpoint_enabled_status {
4429 my ($filename, $line, $status) = @_;
4431 _get_breakpoint_data_ref($filename, $line)->{'enabled'} =
4438 sub _enable_breakpoint_temp_enabled_status {
4439 my ($filename, $line) = @_;
4441 _get_breakpoint_data_ref($filename, $line)->{'temp_enabled'} = 1;
4446 sub _cancel_breakpoint_temp_enabled_status {
4447 my ($filename, $line) = @_;
4449 my $ref = _get_breakpoint_data_ref($filename, $line);
4451 delete ($ref->{'temp_enabled'});
4454 _delete_breakpoint_data_ref($filename, $line);
4460 sub _is_breakpoint_enabled {
4461 my ($filename, $line) = @_;
4463 my $data_ref = _get_breakpoint_data_ref($filename, $line);
4464 return ($data_ref->{'enabled'} || $data_ref->{'temp_enabled'});
4467 =head2 C<cmd_wrapper()> (API)
4469 C<cmd_wrapper()> allows the debugger to switch command sets
4470 depending on the value of the C<CommandSet> option.
4472 It tries to look up the command in the C<%set> package-level I<lexical>
4473 (which means external entities can't fiddle with it) and create the name of
4474 the sub to call based on the value found in the hash (if it's there). I<All>
4475 of the commands to be handled in a set have to be added to C<%set>; if they
4476 aren't found, the 5.8.0 equivalent is called (if there is one).
4478 This code uses symbolic references.
4485 my $dblineno = shift;
4487 # Assemble the command subroutine's name by looking up the
4488 # command set and command name in %set. If we can't find it,
4489 # default to the older version of the command.
4491 . ( $set{$CommandSet}{$cmd}
4492 || ( $cmd =~ /\A[<>{]+/o ? 'prepost' : $cmd ) );
4494 # Call the command subroutine, call it by name.
4495 return __PACKAGE__->can($call)->( $cmd, $line, $dblineno );
4496 } ## end sub cmd_wrapper
4498 =head3 C<cmd_a> (command)
4500 The C<a> command handles pre-execution actions. These are associated with a
4501 particular line, so they're stored in C<%dbline>. We default to the current
4502 line if none is specified.
4508 my $line = shift || ''; # [.|line] expr
4511 # If it's dot (here), or not all digits, use the current line.
4512 $line =~ s/\A\./$dbline/;
4514 # Should be a line number followed by an expression.
4515 if ( my ($lineno, $expr) = $line =~ /^\s*(\d*)\s*(\S.+)/ ) {
4517 if (! length($lineno)) {
4521 # If we have an expression ...
4522 if ( length $expr ) {
4524 # ... but the line isn't breakable, complain.
4525 if ( $dbline[$lineno] == 0 ) {
4527 "Line $lineno($dbline[$lineno]) does not have an action?\n";
4531 # It's executable. Record that the line has an action.
4532 $had_breakpoints{$filename} |= 2;
4534 # Remove any action, temp breakpoint, etc.
4535 $dbline{$lineno} =~ s/\0[^\0]*//;
4537 # Add the action to the line.
4538 $dbline{$lineno} .= "\0" . action($expr);
4540 _set_breakpoint_enabled_status($filename, $lineno, 1);
4542 } ## end if (length $expr)
4543 } ## end if ($line =~ /^\s*(\d*)\s*(\S.+)/)
4548 "Adding an action requires an optional lineno and an expression\n"
4553 =head3 C<cmd_A> (command)
4555 Delete actions. Similar to above, except the delete code is in a separate
4556 subroutine, C<delete_action>.
4562 my $line = shift || '';
4566 $line =~ s/^\./$dbline/;
4568 # Call delete_action with a null param to delete them all.
4569 # The '1' forces the eval to be true. It'll be false only
4570 # if delete_action blows up for some reason, in which case
4571 # we print $@ and get out.
4572 if ( $line eq '*' ) {
4573 if (! eval { _delete_all_actions(); 1 }) {
4579 # There's a real line number. Pass it to delete_action.
4580 # Error trapping is as above.
4581 elsif ( $line =~ /^(\S.*)/ ) {
4582 if (! eval { delete_action($1); 1 }) {
4588 # Swing and a miss. Bad syntax.
4591 "Deleting an action requires a line number, or '*' for all\n" ; # hint
4595 =head3 C<delete_action> (API)
4597 C<delete_action> accepts either a line number or C<undef>. If a line number
4598 is specified, we check for the line being executable (if it's not, it
4599 couldn't have had an action). If it is, we just take the action off (this
4600 will get any kind of an action, including breakpoints).
4604 sub _remove_action_from_dbline {
4607 $dbline{$i} =~ s/\0[^\0]*//; # \^a
4608 delete $dbline{$i} if $dbline{$i} eq '';
4613 sub _delete_all_actions {
4614 print {$OUT} "Deleting all actions...\n";
4616 for my $file ( keys %had_breakpoints ) {
4617 local *dbline = $main::{ '_<' . $file };
4620 for my $i (1 .. $max) {
4621 if ( defined $dbline{$i} ) {
4622 _remove_action_from_dbline($i);
4626 unless ( $had_breakpoints{$file} &= ~2 ) {
4627 delete $had_breakpoints{$file};
4637 if ( defined($i) ) {
4639 die "Line $i has no action .\n" if $dbline[$i] == 0;
4641 # Nuke whatever's there.
4642 _remove_action_from_dbline($i);
4645 _delete_all_actions();
4649 =head3 C<cmd_b> (command)
4651 Set breakpoints. Since breakpoints can be set in so many places, in so many
4652 ways, conditionally or not, the breakpoint code is kind of complex. Mostly,
4653 we try to parse the command type, and then shuttle it off to an appropriate
4654 subroutine to actually do the work of setting the breakpoint in the right
4661 my $line = shift; # [.|line] [cond]
4664 my $default_cond = sub {
4666 return length($cond) ? $cond : '1';
4669 # Make . the current line number if it's there..
4670 $line =~ s/^\.(\s|\z)/$dbline$1/;
4672 # No line number, no condition. Simple break on current line.
4673 if ( $line =~ /^\s*$/ ) {
4674 cmd_b_line( $dbline, 1 );
4677 # Break on load for a file.
4678 elsif ( my ($file) = $line =~ /^load\b\s*(.*)/ ) {
4683 # b compile|postpone <some sub> [<condition>]
4684 # The interpreter actually traps this one for us; we just put the
4685 # necessary condition in the %postponed hash.
4686 elsif ( my ($action, $subname, $cond)
4687 = $line =~ /^(postpone|compile)\b\s*([':A-Za-z_][':\w]*)\s*(.*)/ ) {
4689 # De-Perl4-ify the name - ' separators to ::.
4690 $subname =~ s/'/::/g;
4692 # Qualify it into the current package unless it's already qualified.
4693 $subname = "${package}::" . $subname unless $subname =~ /::/;
4695 # Add main if it starts with ::.
4696 $subname = "main" . $subname if substr( $subname, 0, 2 ) eq "::";
4698 # Save the break type for this sub.
4699 $postponed{$subname} = (($action eq 'postpone')
4700 ? ( "break +0 if " . $default_cond->($cond) )
4702 } ## end elsif ($line =~ ...
4703 # b <filename>:<line> [<condition>]
4704 elsif (my ($filename, $line_num, $cond)
4705 = $line =~ /\A(\S+[^:]):(\d+)\s*(.*)/ms) {
4706 cmd_b_filename_line(
4709 (length($cond) ? $cond : '1'),
4712 # b <sub name> [<condition>]
4713 elsif ( my ($new_subname, $new_cond) =
4714 $line =~ /^([':A-Za-z_][':\w]*(?:\[.*\])?)\s*(.*)/ ) {
4717 $subname = $new_subname;
4718 cmd_b_sub( $subname, $default_cond->($new_cond) );
4721 # b <line> [<condition>].
4722 elsif ( my ($line_n, $cond) = $line =~ /^(\d*)\s*(.*)/ ) {
4724 # Capture the line. If none, it's the current line.
4725 $line = $line_n || $dbline;
4728 cmd_b_line( $line, $default_cond->($cond) );
4731 # Line didn't make sense.
4733 print "confused by line($line)?\n";
4739 =head3 C<break_on_load> (API)
4741 We want to break when this file is loaded. Mark this file in the
4742 C<%break_on_load> hash, and note that it has a breakpoint in
4743 C<%had_breakpoints>.
4749 $break_on_load{$file} = 1;
4750 $had_breakpoints{$file} |= 1;
4753 =head3 C<report_break_on_load> (API)
4755 Gives us an array of filenames that are set to break on load. Note that
4756 only files with break-on-load are in here, so simply showing the keys
4761 sub report_break_on_load {
4762 sort keys %break_on_load;
4765 =head3 C<cmd_b_load> (command)
4767 We take the file passed in and try to find it in C<%INC> (which maps modules
4768 to files they came from). We mark those files for break-on-load via
4769 C<break_on_load> and then report that it was done.
4777 # This is a block because that way we can use a redo inside it
4778 # even without there being any looping structure at all outside it.
4781 # Save short name and full path if found.
4783 push @files, $::INC{$file} if $::INC{$file};
4785 # Tack on .pm and do it again unless there was a '.' in the name
4787 $file .= '.pm', redo unless $file =~ /\./;
4790 # Do the real work here.
4791 break_on_load($_) for @files;
4793 # All the files that have break-on-load breakpoints.
4794 @files = report_break_on_load;
4796 # Normalize for the purposes of our printing this.
4799 print $OUT "Will stop on load of '@files'.\n";
4800 } ## end sub cmd_b_load
4802 =head3 C<$filename_error> (API package global)
4804 Several of the functions we need to implement in the API need to work both
4805 on the current file and on other files. We don't want to duplicate code, so
4806 C<$filename_error> is used to contain the name of the file that's being
4807 worked on (if it's not the current one).
4809 We can now build functions in pairs: the basic function works on the current
4810 file, and uses C<$filename_error> as part of its error message. Since this is
4811 initialized to C<"">, no filename will appear when we are working on the
4814 The second function is a wrapper which does the following:
4820 Localizes C<$filename_error> and sets it to the name of the file to be processed.
4824 Localizes the C<*dbline> glob and reassigns it to point to the file we want to process.
4828 Calls the first function.
4830 The first function works on the I<current> file (i.e., the one we changed to),
4831 and prints C<$filename_error> in the error message (the name of the other file)
4832 if it needs to. When the functions return, C<*dbline> is restored to point
4833 to the actual current file (the one we're executing in) and
4834 C<$filename_error> is restored to C<"">. This restores everything to
4835 the way it was before the second function was called at all.
4837 See the comments in C<breakable_line> and C<breakable_line_in_file> for more
4844 use vars qw($filename_error);
4845 $filename_error = '';
4847 =head3 breakable_line(from, to) (API)
4849 The subroutine decides whether or not a line in the current file is breakable.
4850 It walks through C<@dbline> within the range of lines specified, looking for
4851 the first line that is breakable.
4853 If C<$to> is greater than C<$from>, the search moves forwards, finding the
4854 first line I<after> C<$to> that's breakable, if there is one.
4856 If C<$from> is greater than C<$to>, the search goes I<backwards>, finding the
4857 first line I<before> C<$to> that's breakable, if there is one.
4861 sub breakable_line {
4863 my ( $from, $to ) = @_;
4865 # $i is the start point. (Where are the FORTRAN programs of yesteryear?)
4868 # If there are at least 2 arguments, we're trying to search a range.
4871 # $delta is positive for a forward search, negative for a backward one.
4872 my $delta = $from < $to ? +1 : -1;
4874 # Keep us from running off the ends of the file.
4875 my $limit = $delta > 0 ? $#dbline : 1;
4877 # Clever test. If you're a mathematician, it's obvious why this
4878 # test works. If not:
4879 # If $delta is positive (going forward), $limit will be $#dbline.
4880 # If $to is less than $limit, ($limit - $to) will be positive, times
4881 # $delta of 1 (positive), so the result is > 0 and we should use $to
4882 # as the stopping point.
4884 # If $to is greater than $limit, ($limit - $to) is negative,
4885 # times $delta of 1 (positive), so the result is < 0 and we should
4886 # use $limit ($#dbline) as the stopping point.
4888 # If $delta is negative (going backward), $limit will be 1.
4889 # If $to is zero, ($limit - $to) will be 1, times $delta of -1
4890 # (negative) so the result is > 0, and we use $to as the stopping
4893 # If $to is less than zero, ($limit - $to) will be positive,
4894 # times $delta of -1 (negative), so the result is not > 0, and
4895 # we use $limit (1) as the stopping point.
4897 # If $to is 1, ($limit - $to) will zero, times $delta of -1
4898 # (negative), still giving zero; the result is not > 0, and
4899 # we use $limit (1) as the stopping point.
4901 # if $to is >1, ($limit - $to) will be negative, times $delta of -1
4902 # (negative), giving a positive (>0) value, so we'll set $limit to
4905 $limit = $to if ( $limit - $to ) * $delta > 0;
4907 # The real search loop.
4908 # $i starts at $from (the point we want to start searching from).
4909 # We move through @dbline in the appropriate direction (determined
4910 # by $delta: either -1 (back) or +1 (ahead).
4911 # We stay in as long as we haven't hit an executable line
4912 # ($dbline[$i] == 0 means not executable) and we haven't reached
4913 # the limit yet (test similar to the above).
4914 $i += $delta while $dbline[$i] == 0 and ( $limit - $i ) * $delta > 0;
4916 } ## end if (@_ >= 2)
4918 # If $i points to a line that is executable, return that.
4919 return $i unless $dbline[$i] == 0;
4921 # Format the message and print it: no breakable lines in range.
4922 my ( $pl, $upto ) = ( '', '' );
4923 ( $pl, $upto ) = ( 's', "..$to" ) if @_ >= 2 and $from != $to;
4925 # If there's a filename in filename_error, we'll see it.
4927 die "Line$pl $from$upto$filename_error not breakable\n";
4928 } ## end sub breakable_line
4930 =head3 breakable_line_in_filename(file, from, to) (API)
4932 Like C<breakable_line>, but look in another file.
4936 sub breakable_line_in_filename {
4938 # Capture the file name.
4941 # Swap the magic line array over there temporarily.
4942 local *dbline = $main::{ '_<' . $f };
4944 # If there's an error, it's in this other file.
4945 local $filename_error = " of '$f'";
4947 # Find the breakable line.
4950 # *dbline and $filename_error get restored when this block ends.
4952 } ## end sub breakable_line_in_filename
4954 =head3 break_on_line(lineno, [condition]) (API)
4956 Adds a breakpoint with the specified condition (or 1 if no condition was
4957 specified) to the specified line. Dies if it can't.
4963 my $cond = @_ ? shift(@_) : 1;
4969 # Woops, not a breakable line. $filename_error allows us to say
4970 # if it was in a different file.
4971 die "Line $i$filename_error not breakable.\n" if $dbline[$i] == 0;
4973 # Mark this file as having breakpoints in it.
4974 $had_breakpoints{$filename} |= 1;
4976 # If there is an action or condition here already ...
4977 if ( $dbline{$i} ) {
4979 # ... swap this condition for the existing one.
4980 $dbline{$i} =~ s/^[^\0]*/$cond/;
4984 # Nothing here - just add the condition.
4985 $dbline{$i} = $cond;
4987 _set_breakpoint_enabled_status($filename, $i, 1);
4991 } ## end sub break_on_line
4993 =head3 cmd_b_line(line, [condition]) (command)
4995 Wrapper for C<break_on_line>. Prints the failure message if it
5001 if (not eval { break_on_line(@_); 1 }) {
5003 print $OUT $@ and return;
5007 } ## end sub cmd_b_line
5009 =head3 cmd_b_filename_line(line, [condition]) (command)
5011 Wrapper for C<break_on_filename_line>. Prints the failure message if it
5016 sub cmd_b_filename_line {
5017 if (not eval { break_on_filename_line(@_); 1 }) {
5019 print $OUT $@ and return;
5025 =head3 break_on_filename_line(file, line, [condition]) (API)
5027 Switches to the file specified and then calls C<break_on_line> to set
5032 sub break_on_filename_line {
5035 my $cond = @_ ? shift(@_) : 1;
5037 # Switch the magical hash temporarily.
5038 local *dbline = $main::{ '_<' . $f };
5040 # Localize the variables that break_on_line uses to make its message.
5041 local $filename_error = " of '$f'";
5042 local $filename = $f;
5044 # Add the breakpoint.
5045 break_on_line( $i, $cond );
5048 } ## end sub break_on_filename_line
5050 =head3 break_on_filename_line_range(file, from, to, [condition]) (API)
5052 Switch to another file, search the range of lines specified for an
5053 executable one, and put a breakpoint on the first one you find.
5057 sub break_on_filename_line_range {
5061 my $cond = @_ ? shift(@_) : 1;
5063 # Find a breakable line if there is one.
5064 my $i = breakable_line_in_filename( $f, $from, $to );
5066 # Add the breakpoint.
5067 break_on_filename_line( $f, $i, $cond );
5070 } ## end sub break_on_filename_line_range
5072 =head3 subroutine_filename_lines(subname, [condition]) (API)
5074 Search for a subroutine within a given file. The condition is ignored.
5075 Uses C<find_sub> to locate the desired subroutine.
5079 sub subroutine_filename_lines {
5080 my ( $subname ) = @_;
5082 # Returned value from find_sub() is fullpathname:startline-endline.
5083 # The match creates the list (fullpathname, start, end).
5084 return (find_sub($subname) =~ /^(.*):(\d+)-(\d+)$/);
5085 } ## end sub subroutine_filename_lines
5087 =head3 break_subroutine(subname) (API)
5089 Places a break on the first line possible in the specified subroutine. Uses
5090 C<subroutine_filename_lines> to find the subroutine, and
5091 C<break_on_filename_line_range> to place the break.
5095 sub break_subroutine {
5096 my $subname = shift;
5098 # Get filename, start, and end.
5099 my ( $file, $s, $e ) = subroutine_filename_lines($subname)
5100 or die "Subroutine $subname not found.\n";
5103 # Null condition changes to '1' (always true).
5104 my $cond = @_ ? shift(@_) : 1;
5106 # Put a break the first place possible in the range of lines
5107 # that make up this subroutine.
5108 break_on_filename_line_range( $file, $s, $e, $cond );
5111 } ## end sub break_subroutine
5113 =head3 cmd_b_sub(subname, [condition]) (command)
5115 We take the incoming subroutine name and fully-qualify it as best we can.
5119 =item 1. If it's already fully-qualified, leave it alone.
5121 =item 2. Try putting it in the current package.
5123 =item 3. If it's not there, try putting it in CORE::GLOBAL if it exists there.
5125 =item 4. If it starts with '::', put it in 'main::'.
5129 After all this cleanup, we call C<break_subroutine> to try to set the
5135 my $subname = shift;
5136 my $cond = @_ ? shift : 1;
5138 # If the subname isn't a code reference, qualify it so that
5139 # break_subroutine() will work right.
5140 if ( ref($subname) ne 'CODE' ) {
5143 $subname =~ s/'/::/g;
5146 # Put it in this package unless it's already qualified.
5147 if ($subname !~ /::/)
5149 $subname = $package . '::' . $subname;
5152 # Requalify it into CORE::GLOBAL if qualifying it into this
5153 # package resulted in its not being defined, but only do so
5154 # if it really is in CORE::GLOBAL.
5155 my $core_name = "CORE::GLOBAL::$s";
5156 if ((!defined(&$subname))
5158 and (defined &{$core_name}))
5160 $subname = $core_name;
5163 # Put it in package 'main' if it has a leading ::.
5164 if ($subname =~ /\A::/)
5166 $subname = "main" . $subname;
5168 } ## end if ( ref($subname) ne 'CODE' ) {
5170 # Try to set the breakpoint.
5171 if (not eval { break_subroutine( $subname, $cond ); 1 }) {
5178 } ## end sub cmd_b_sub
5180 =head3 C<cmd_B> - delete breakpoint(s) (command)
5182 The command mostly parses the command line and tries to turn the argument
5183 into a line spec. If it can't, it uses the current line. It then calls
5184 C<delete_breakpoint> to actually do the work.
5186 If C<*> is specified, C<cmd_B> calls C<delete_breakpoint> with no arguments,
5187 thereby deleting all the breakpoints.
5194 # No line spec? Use dbline.
5195 # If there is one, use it if it's non-zero, or wipe it out if it is.
5196 my $line = ( $_[0] =~ /\A\./ ) ? $dbline : (shift || '');
5199 # If the line was dot, make the line the current one.
5200 $line =~ s/^\./$dbline/;
5202 # If it's * we're deleting all the breakpoints.
5203 if ( $line eq '*' ) {
5204 if (not eval { delete_breakpoint(); 1 }) {
5209 # If there is a line spec, delete the breakpoint on that line.
5210 elsif ( $line =~ /\A(\S.*)/ ) {
5211 if (not eval { delete_breakpoint( $line || $dbline ); 1 }) {
5215 } ## end elsif ($line =~ /^(\S.*)/)
5220 "Deleting a breakpoint requires a line number, or '*' for all\n"
5227 =head3 delete_breakpoint([line]) (API)
5229 This actually does the work of deleting either a single breakpoint, or all
5232 For a single line, we look for it in C<@dbline>. If it's nonbreakable, we
5233 just drop out with a message saying so. If it is, we remove the condition
5234 part of the 'condition\0action' that says there's a breakpoint here. If,
5235 after we've done that, there's nothing left, we delete the corresponding
5236 line in C<%dbline> to signal that no action needs to be taken for this line.
5238 For all breakpoints, we iterate through the keys of C<%had_breakpoints>,
5239 which lists all currently-loaded files which have breakpoints. We then look
5240 at each line in each of these files, temporarily switching the C<%dbline>
5241 and C<@dbline> structures to point to the files in question, and do what
5242 we did in the single line case: delete the condition in C<@dbline>, and
5243 delete the key in C<%dbline> if nothing's left.
5245 We then wholesale delete C<%postponed>, C<%postponed_file>, and
5246 C<%break_on_load>, because these structures contain breakpoints for files
5247 and code that haven't been loaded yet. We can just kill these off because there
5248 are no magical debugger structures associated with them.
5252 sub _remove_breakpoint_entry {
5256 _delete_breakpoint_data_ref($fn, $i);
5261 sub _delete_all_breakpoints {
5262 print {$OUT} "Deleting all breakpoints...\n";
5264 # %had_breakpoints lists every file that had at least one
5266 for my $fn ( keys %had_breakpoints ) {
5268 # Switch to the desired file temporarily.
5269 local *dbline = $main::{ '_<' . $fn };
5273 # For all lines in this file ...
5274 for my $i (1 .. $max) {
5276 # If there's a breakpoint or action on this line ...
5277 if ( defined $dbline{$i} ) {
5279 # ... remove the breakpoint.
5280 $dbline{$i} =~ s/\A[^\0]+//;
5281 if ( $dbline{$i} =~ s/\A\0?\z// ) {
5282 # Remove the entry altogether if no action is there.
5283 _remove_breakpoint_entry($fn, $i);
5285 } ## end if (defined $dbline{$i...
5286 } ## end for $i (1 .. $max)
5288 # If, after we turn off the "there were breakpoints in this file"
5289 # bit, the entry in %had_breakpoints for this file is zero,
5290 # we should remove this file from the hash.
5291 if ( not $had_breakpoints{$fn} &= (~1) ) {
5292 delete $had_breakpoints{$fn};
5294 } ## end for my $fn (keys %had_breakpoints)
5296 # Kill off all the other breakpoints that are waiting for files that
5297 # haven't been loaded yet.
5299 undef %postponed_file;
5300 undef %break_on_load;
5305 sub _delete_breakpoint_from_line {
5308 # Woops. This line wasn't breakable at all.
5309 die "Line $i not breakable.\n" if $dbline[$i] == 0;
5311 # Kill the condition, but leave any action.
5312 $dbline{$i} =~ s/\A[^\0]*//;
5314 # Remove the entry entirely if there's no action left.
5315 if ($dbline{$i} eq '') {
5316 _remove_breakpoint_entry($filename, $i);
5322 sub delete_breakpoint {
5325 # If we got a line, delete just that one.
5326 if ( defined($i) ) {
5327 _delete_breakpoint_from_line($i);
5329 # No line; delete them all.
5331 _delete_all_breakpoints();
5337 =head3 cmd_stop (command)
5339 This is meant to be part of the new command API, but it isn't called or used
5340 anywhere else in the debugger. XXX It is probably meant for use in development
5345 sub cmd_stop { # As on ^C, but not signal-safy.
5349 =head3 C<cmd_e> - threads
5351 Display the current thread id:
5355 This could be how (when implemented) to send commands to this thread id (e cmd)
5356 or that thread id (e tid cmd).
5363 unless (exists($INC{'threads.pm'})) {
5364 print "threads not loaded($ENV{PERL5DB_THREADED})
5365 please run the debugger with PERL5DB_THREADED=1 set in the environment\n";
5367 my $tid = threads->tid;
5368 print "thread id: $tid\n";
5372 =head3 C<cmd_E> - list of thread ids
5374 Display the list of available thread ids:
5378 This could be used (when implemented) to send commands to all threads (E cmd).
5385 unless (exists($INC{'threads.pm'})) {
5386 print "threads not loaded($ENV{PERL5DB_THREADED})
5387 please run the debugger with PERL5DB_THREADED=1 set in the environment\n";
5389 my $tid = threads->tid;
5390 print "thread ids: ".join(', ',
5391 map { ($tid == $_->tid ? '<'.$_->tid.'>' : $_->tid) } threads->list
5396 =head3 C<cmd_h> - help command (command)
5398 Does the work of either
5404 Showing all the debugger help
5408 Showing help for a specific command
5415 use vars qw($summary);
5420 # If we have no operand, assume null.
5421 my $line = shift || '';
5423 # 'h h'. Print the long-format help.
5424 if ( $line =~ /\Ah\s*\z/ ) {
5428 # 'h <something>'. Search for the command and print only its help.
5429 elsif ( my ($asked) = $line =~ /\A(\S.*)\z/ ) {
5431 # support long commands; otherwise bogus errors
5432 # happen when you ask for h on <CR> for example
5433 my $qasked = quotemeta($asked); # for searching; we don't
5434 # want to use it as a pattern.
5435 # XXX: finds CR but not <CR>
5437 # Search the help string for the command.
5439 $help =~ /^ # Start of a line
5441 (?:[IB]<) # Optional markup
5442 $qasked # The requested command
5447 # It's there; pull it out and print it.
5451 (?:[IB]<) # Optional markup
5452 $qasked # The command
5453 ([\s\S]*?) # Description line(s)
5454 \n) # End of last description line
5455 (?!\s) # Next line not starting with
5464 # Not found; not a debugger command.
5466 print_help("B<$asked> is not a debugger command.\n");
5468 } ## end elsif ($line =~ /^(\S.*)$/)
5470 # 'h' - print the summary help.
5472 print_help($summary);
5476 =head3 C<cmd_i> - inheritance display
5478 Display the (nested) parentage of the module or object given.
5485 foreach my $isa ( split( /\s+/, $line ) ) {
5487 # The &-call is here to ascertain the mutability of @_.
5495 defined( ${"$_\::VERSION"} )
5496 ? ' ' . ${"$_\::VERSION"}
5498 } @{mro::get_linear_isa(ref($isa) || $isa)}
5504 =head3 C<cmd_l> - list lines (command)
5506 Most of the command is taken up with transforming all the different line
5507 specification syntaxes into 'start-stop'. After that is done, the command
5508 runs a loop over C<@dbline> for the specified range of lines. It handles
5509 the printing of each line and any markers (C<==E<gt>> for current line,
5510 C<b> for break on this line, C<a> for action on this line, C<:> for this
5513 We save the last line listed in the C<$start> global for further listing
5520 foreach my $v (@_) {
5530 foreach my $v (@_) {
5538 sub _minify_to_max {
5541 $$ref = _min($$ref, $max);
5546 sub _cmd_l_handle_var_name {
5547 my $var_name = shift;
5549 $evalarg = $var_name;
5551 my ($s) = DB::eval();
5553 # Ooops. Bad scalar.
5555 print {$OUT} "Error: $@\n";
5559 # Good scalar. If it's a reference, find what it points to.
5561 print {$OUT} "Interpreted as: $1 $s\n";
5564 # Call self recursively to really do the command.
5565 return _cmd_l_main( $s );
5568 sub _cmd_l_handle_subname {
5573 $subname =~ s/\'/::/;
5575 # Put it in this package unless it starts with ::.
5576 $subname = $package . "::" . $subname unless $subname =~ /::/;
5578 # Put it in CORE::GLOBAL if t doesn't start with :: and
5579 # it doesn't live in this package and it lives in CORE::GLOBAL.
5580 $subname = "CORE::GLOBAL::$s"
5581 if not defined &$subname
5583 and defined &{"CORE::GLOBAL::$s"};
5585 # Put leading '::' names into 'main::'.
5586 $subname = "main" . $subname if substr( $subname, 0, 2 ) eq "::";
5588 # Get name:start-stop from find_sub, and break this up at
5590 my @pieces = split( /:/, find_sub($subname) || $sub{$subname} );
5592 # Pull off start-stop.
5593 my $subrange = pop @pieces;
5595 # If the name contained colons, the split broke it up.
5596 # Put it back together.
5597 $file = join( ':', @pieces );
5599 # If we're not in that file, switch over to it.
5600 if ( $file ne $filename ) {
5601 if (! $slave_editor) {
5602 print {$OUT} "Switching to file '$file'.\n";
5605 # Switch debugger's magic structures.
5606 *dbline = $main::{ '_<' . $file };
5609 } ## end if ($file ne $filename)
5611 # Subrange is 'start-stop'. If this is less than a window full,
5612 # swap it to 'start+', which will list a window from the start point.
5614 if ( eval($subrange) < -$window ) {
5615 $subrange =~ s/-.*/+/;
5618 # Call self recursively to list the range.
5619 return _cmd_l_main( $subrange );
5620 } ## end if ($subrange)
5624 print {$OUT} "Subroutine $subname not found.\n";
5630 # Compute new range to list.
5631 $incr = $window - 1;
5634 return _cmd_l_main( $start . '-' . ( $start + $incr ) );
5638 my ($new_start, $new_incr) = @_;
5640 # Don't reset start for 'l +nnn'.
5641 $start = $new_start if $new_start;
5643 # Increment for list. Use window size if not specified.
5644 # (Allows 'l +' to work.)
5645 $incr = $new_incr || ($window - 1);
5647 # Create a line range we'll understand, and recurse to do it.
5648 return _cmd_l_main( $start . '-' . ( $start + $incr ) );
5651 sub _cmd_l_calc_initial_end_and_i {
5652 my ($spec, $start_match, $end_match) = @_;
5654 # Determine end point; use end of file if not specified.
5655 my $end = ( !defined $start_match ) ? $max :
5656 ( $end_match ? $end_match : $start_match );
5658 # Go on to the end, and then stop.
5659 _minify_to_max(\$end);
5661 # Determine start line.
5662 my $i = $start_match;
5676 my ($spec, $current_line, $start_match, $end_match) = @_;
5679 _cmd_l_calc_initial_end_and_i($spec, $start_match, $end_match);
5681 # If we're running under a slave editor, force it to show the lines.
5682 if ($slave_editor) {
5683 print {$OUT} "\032\032$filename:$i:0\n";
5686 # We're doing it ourselves. We want to show the line and special
5688 # - the current line in execution
5689 # - whether a line is breakable or not
5690 # - whether a line has a break or not
5691 # - whether a line has an action or not
5694 for ( ; $i <= $end ; $i++ ) {
5696 # Check for breakpoints and actions.
5697 my ( $stop, $action );
5699 ( $stop, $action ) = split( /\0/, $dbline{$i} );
5702 # ==> if this is the current line in execution,
5703 # : if it's breakable.
5705 ( $i == $current_line and $filename eq $filename_ini )
5707 : ( $dbline[$i] + 0 ? ':' : ' ' );
5709 # Add break and action indicators.
5710 $arrow .= 'b' if $stop;
5711 $arrow .= 'a' if $action;
5714 print {$OUT} "$i$arrow\t", $dbline[$i];
5716 # Move on to the next line. Drop out on an interrupt.
5721 } ## end for (; $i <= $end ; $i++)
5723 # Line the prompt up; print a newline if the last line listed
5724 # didn't have a newline.
5725 if ($dbline[ $i - 1 ] !~ /\n\z/) {
5728 } ## end else [ if ($slave_editor)
5730 # Save the point we last listed to in case another relative 'l'
5731 # command is desired. Don't let it run off the end.
5733 _minify_to_max(\$start);
5741 # If this is '-something', delete any spaces after the dash.
5742 $spec =~ s/\A-\s*\z/-/;
5744 # If the line is '$something', assume this is a scalar containing a
5746 # Set up for DB::eval() - evaluate in *user* context.
5747 if ( my ($var_name) = $spec =~ /\A(\$.*)/s ) {
5748 return _cmd_l_handle_var_name($var_name);
5750 # l name. Try to find a sub by that name.
5751 elsif ( ($subname) = $spec =~ /\A([\':A-Za-z_][\':\w]*(?:\[.*\])?)/s ) {
5752 return _cmd_l_handle_subname();
5755 elsif ( $spec !~ /\S/ ) {
5756 return _cmd_l_empty();
5758 # l [start]+number_of_lines
5759 elsif ( my ($new_start, $new_incr) = $spec =~ /\A(\d*)\+(\d*)\z/ ) {
5760 return _cmd_l_plus($new_start, $new_incr);
5762 # l start-stop or l start,stop
5763 elsif (my ($s, $e) = $spec =~ /^(?:(-?[\d\$\.]+)(?:[-,]([\d\$\.]+))?)?/ ) {
5764 return _cmd_l_range($spec, $line, $s, $e);
5771 my (undef, $line) = @_;
5773 return _cmd_l_main($line);
5776 =head3 C<cmd_L> - list breakpoints, actions, and watch expressions (command)
5778 To list breakpoints, the command has to look determine where all of them are
5779 first. It starts a C<%had_breakpoints>, which tells us what all files have
5780 breakpoints and/or actions. For each file, we switch the C<*dbline> glob (the
5781 magic source and breakpoint data structures) to the file, and then look
5782 through C<%dbline> for lines with breakpoints and/or actions, listing them
5783 out. We look through C<%postponed> not-yet-compiled subroutines that have
5784 breakpoints, and through C<%postponed_file> for not-yet-C<require>'d files
5785 that have breakpoints.
5787 Watchpoints are simpler: we just list the entries in C<@to_watch>.
5791 sub _cmd_L_calc_arg {
5792 # If no argument, list everything. Pre-5.8.0 version always lists
5794 my $arg = shift || 'abw';
5795 if ($CommandSet ne '580')
5803 sub _cmd_L_calc_wanted_flags {
5804 my $arg = _cmd_L_calc_arg(shift);
5806 return (map { index($arg, $_) >= 0 ? 1 : 0 } qw(a b w));
5810 sub _cmd_L_handle_breakpoints {
5811 my ($handle_db_line) = @_;
5814 # Look in all the files with breakpoints...
5815 for my $file ( keys %had_breakpoints ) {
5817 # Temporary switch to this file.
5818 local *dbline = $main::{ '_<' . $file };
5820 # Set up to look through the whole file.
5822 my $was; # Flag: did we print something
5825 # For each line in the file ...
5826 for my $i (1 .. $max) {
5828 # We've got something on this line.
5829 if ( defined $dbline{$i} ) {
5831 # Print the header if we haven't.
5833 print {$OUT} "$file:\n";
5837 print {$OUT} " $i:\t", $dbline[$i];
5839 $handle_db_line->($dbline{$i});
5841 # Quit if the user hit interrupt.
5843 last BREAKPOINTS_SCAN;
5845 } ## end if (defined $dbline{$i...
5846 } ## end for my $i (1 .. $max)
5847 } ## end for my $file (keys %had_breakpoints)
5852 sub _cmd_L_handle_postponed_breakpoints {
5853 my ($handle_db_line) = @_;
5855 print {$OUT} "Postponed breakpoints in files:\n";
5858 for my $file ( keys %postponed_file ) {
5859 my $db = $postponed_file{$file};
5860 print {$OUT} " $file:\n";
5861 for my $line ( sort { $a <=> $b } keys %$db ) {
5862 print {$OUT} " $line:\n";
5864 $handle_db_line->($db->{$line});
5867 last POSTPONED_SCANS;
5871 last POSTPONED_SCANS;
5882 my ($action_wanted, $break_wanted, $watch_wanted) =
5883 _cmd_L_calc_wanted_flags(shift);
5885 my $handle_db_line = sub {
5888 my ( $stop, $action ) = split( /\0/, $l );
5890 if ($stop and $break_wanted) {
5891 print {$OUT} " break if (", $stop, ")\n"
5894 if ($action && $action_wanted) {
5895 print {$OUT} " action: ", $action, "\n"
5901 # Breaks and actions are found together, so we look in the same place
5903 if ( $break_wanted or $action_wanted ) {
5904 _cmd_L_handle_breakpoints($handle_db_line);
5907 # Look for breaks in not-yet-compiled subs:
5908 if ( %postponed and $break_wanted ) {
5909 print {$OUT} "Postponed breakpoints in subroutines:\n";
5912 for $subname ( keys %postponed ) {
5913 print {$OUT} " $subname\t$postponed{$subname}\n";
5918 } ## end if (%postponed and $break_wanted)
5920 # Find files that have not-yet-loaded breaks:
5921 my @have = map { # Combined keys
5922 keys %{ $postponed_file{$_} }
5923 } keys %postponed_file;
5925 # If there are any, list them.
5926 if ( @have and ( $break_wanted or $action_wanted ) ) {
5927 _cmd_L_handle_postponed_breakpoints($handle_db_line);
5928 } ## end if (@have and ($break_wanted...
5930 if ( %break_on_load and $break_wanted ) {
5931 print {$OUT} "Breakpoints on load:\n";
5932 BREAK_ON_LOAD: for my $filename ( keys %break_on_load ) {
5933 print {$OUT} " $filename\n";
5934 last BREAK_ON_LOAD if $signal;
5936 } ## end if (%break_on_load and...
5938 if ($watch_wanted and ( $trace & 2 )) {
5939 print {$OUT} "Watch-expressions:\n" if @to_watch;
5940 TO_WATCH: for my $expr (@to_watch) {
5941 print {$OUT} " $expr\n";
5942 last TO_WATCH if $signal;
5949 =head3 C<cmd_M> - list modules (command)
5951 Just call C<list_modules>.
5961 =head3 C<cmd_o> - options (command)
5963 If this is just C<o> by itself, we list the current settings via
5964 C<dump_option>. If there's a nonblank value following it, we pass that on to
5965 C<parse_options> for processing.
5971 my $opt = shift || ''; # opt[=val]
5973 # Nonblank. Try to parse and process.
5974 if ( $opt =~ /^(\S.*)/ ) {
5978 # Blank. List the current option settings.
5986 =head3 C<cmd_O> - nonexistent in 5.8.x (command)
5988 Advises the user that the O command has been renamed.
5993 print $OUT "The old O command is now the o command.\n"; # hint
5994 print $OUT "Use 'h' to get current command help synopsis or\n"; #
5995 print $OUT "use 'o CommandSet=pre580' to revert to old usage\n"; #
5998 =head3 C<cmd_v> - view window (command)
6000 Uses the C<$preview> variable set in the second C<BEGIN> block (q.v.) to
6001 move back a few lines to list the selected line in context. Uses C<cmd_l>
6002 to do the actual listing after figuring out the range of line to request.
6006 use vars qw($preview);
6012 # Extract the line to list around. (Astute readers will have noted that
6013 # this pattern will match whether or not a numeric line is specified,
6014 # which means that we'll always enter this loop (though a non-numeric
6015 # argument results in no action at all)).
6016 if ( $line =~ /^(\d*)$/ ) {
6018 # Total number of lines to list (a windowful).
6019 $incr = $window - 1;
6021 # Set the start to the argument given (if there was one).
6024 # Back up by the context amount.
6027 # Put together a linespec that cmd_l will like.
6028 $line = $start . '-' . ( $start + $incr );
6031 cmd_l( 'l', $line );
6032 } ## end if ($line =~ /^(\d*)$/)
6035 =head3 C<cmd_w> - add a watch expression (command)
6037 The 5.8 version of this command adds a watch expression if one is specified;
6038 it does nothing if entered with no operands.
6040 We extract the expression, save it, evaluate it in the user's context, and
6041 save the value. We'll re-evaluate it each time the debugger passes a line,
6042 and will stop (see the code at the top of the command loop) if the value
6043 of any of the expressions changes.
6047 sub _add_watch_expr {
6051 push @to_watch, $expr;
6053 # Parameterize DB::eval and call it to get the expression's value
6054 # in the user's context. This version can handle expressions which
6055 # return a list value.
6057 # The &-call is here to ascertain the mutability of @_.
6058 my ($val) = join( ' ', &DB::eval);
6059 $val = ( defined $val ) ? "'$val'" : 'undef';
6061 # Save the current value of the expression.
6062 push @old_watch, $val;
6064 # We are now watching expressions.
6073 # Null expression if no arguments.
6074 my $expr = shift || '';
6076 # If expression is not null ...
6077 if ( $expr =~ /\A\S/ ) {
6078 _add_watch_expr($expr);
6079 } ## end if ($expr =~ /^(\S.*)/)
6081 # You have to give one to get one.
6083 print $OUT "Adding a watch-expression requires an expression\n"; # hint
6089 =head3 C<cmd_W> - delete watch expressions (command)
6091 This command accepts either a watch expression to be removed from the list
6092 of watch expressions, or C<*> to delete them all.
6094 If C<*> is specified, we simply empty the watch expression list and the
6095 watch expression value list. We also turn off the bit that says we've got
6098 If an expression (or partial expression) is specified, we pattern-match
6099 through the expressions and remove the ones that match. We also discard
6100 the corresponding values. If no watch expressions are left, we turn off
6101 the I<watching expressions> bit.
6107 my $expr = shift || '';
6110 if ( $expr eq '*' ) {
6115 print $OUT "Deleting all watch expressions ...\n";
6118 @to_watch = @old_watch = ();
6121 # Delete one of them.
6122 elsif ( $expr =~ /^(\S.*)/ ) {
6124 # Where we are in the list.
6127 # For each expression ...
6128 foreach (@to_watch) {
6129 my $val = $to_watch[$i_cnt];
6131 # Does this one match the command argument?
6132 if ( $val eq $expr ) { # =~ m/^\Q$i$/) {
6133 # Yes. Turn it off, and its value too.
6134 splice( @to_watch, $i_cnt, 1 );
6135 splice( @old_watch, $i_cnt, 1 );
6138 } ## end foreach (@to_watch)
6140 # We don't bother to turn watching off because
6141 # a) we don't want to stop calling watchfunction() if it exists
6142 # b) foreach over a null list doesn't do anything anyway
6144 } ## end elsif ($expr =~ /^(\S.*)/)
6146 # No command arguments entered.
6149 "Deleting a watch-expression requires an expression, or '*' for all\n"
6154 ### END of the API section
6156 =head1 SUPPORT ROUTINES
6158 These are general support routines that are used in a number of places
6159 throughout the debugger.
6163 save() saves the user's versions of globals that would mess us up in C<@saved>,
6164 and installs the versions we like better.
6170 # Save eval failure, command failure, extended OS error, output field
6171 # separator, input record separator, output record separator and
6172 # the warning setting.
6173 @saved = ( $@, $!, $^E, $,, $/, $\, $^W );
6175 $, = ""; # output field separator is null string
6176 $/ = "\n"; # input record separator is newline
6177 $\ = ""; # output record separator is null string
6178 $^W = 0; # warnings are off
6181 =head2 C<print_lineinfo> - show where we are now
6183 print_lineinfo prints whatever it is that it is handed; it prints it to the
6184 C<$LINEINFO> filehandle instead of just printing it to STDOUT. This allows
6185 us to feed line information to a slave editor without messing up the
6190 sub print_lineinfo {
6192 # Make the terminal sensible if we're not the primary debugger.
6193 resetterm(1) if $LINEINFO eq $OUT and $term_pid != $$;
6196 # $LINEINFO may be undef if $noTTY is set or some other issue.
6199 print {$LINEINFO} @_;
6201 } ## end sub print_lineinfo
6203 =head2 C<postponed_sub>
6205 Handles setting postponed breakpoints in subroutines once they're compiled.
6206 For breakpoints, we use C<DB::find_sub> to locate the source file and line
6207 range for the subroutine, then mark the file as having a breakpoint,
6208 temporarily switch the C<*dbline> glob over to the source file, and then
6209 search the given range of lines to find a breakable line. If we find one,
6210 we set the breakpoint on it, deleting the breakpoint from C<%postponed>.
6214 # The following takes its argument via $evalarg to preserve current @_
6218 # Get the subroutine name.
6219 my $subname = shift;
6221 # If this is a 'break +<n> if <condition>' ...
6222 if ( $postponed{$subname} =~ s/^break\s([+-]?\d+)\s+if\s// ) {
6224 # If there's no offset, use '+0'.
6225 my $offset = $1 || 0;
6227 # find_sub's value is 'fullpath-filename:start-stop'. It's
6228 # possible that the filename might have colons in it too.
6229 my ( $file, $i ) = ( find_sub($subname) =~ /^(.*):(\d+)-.*$/ );
6232 # We got the start line. Add the offset '+<n>' from
6233 # $postponed{subname}.
6236 # Switch to the file this sub is in, temporarily.
6237 local *dbline = $main::{ '_<' . $file };
6239 # No warnings, please.
6240 local $^W = 0; # != 0 is magical below
6242 # This file's got a breakpoint in it.
6243 $had_breakpoints{$file} |= 1;
6245 # Last line in file.
6248 # Search forward until we hit a breakable line or get to
6249 # the end of the file.
6250 ++$i until $dbline[$i] != 0 or $i >= $max;
6252 # Copy the breakpoint in and delete it from %postponed.
6253 $dbline{$i} = delete $postponed{$subname};
6256 # find_sub didn't find the sub.
6259 print $OUT "Subroutine $subname not found.\n";
6262 } ## end if ($postponed{$subname...
6263 elsif ( $postponed{$subname} eq 'compile' ) { $signal = 1 }
6265 #print $OUT "In postponed_sub for '$subname'.\n";
6266 } ## end sub postponed_sub
6270 Called after each required file is compiled, but before it is executed;
6271 also called if the name of a just-compiled subroutine is a key of
6272 C<%postponed>. Propagates saved breakpoints (from C<b compile>, C<b load>,
6273 etc.) into the just-compiled code.
6275 If this is a C<require>'d file, the incoming parameter is the glob
6276 C<*{"_<$filename"}>, with C<$filename> the name of the C<require>'d file.
6278 If it's a subroutine, the incoming parameter is the subroutine name.
6284 # If there's a break, process it.
6285 if ($ImmediateStop) {
6287 # Right, we've stopped. Turn it off.
6290 # Enter the command loop when DB::DB gets called.
6294 # If this is a subroutine, let postponed_sub() deal with it.
6295 if (ref(\$_[0]) ne 'GLOB') {
6296 return postponed_sub(@_);
6299 # Not a subroutine. Deal with the file.
6300 local *dbline = shift;
6301 my $filename = $dbline;
6302 $filename =~ s/^_<//;
6304 $signal = 1, print $OUT "'$filename' loaded...\n"
6305 if $break_on_load{$filename};
6306 print_lineinfo( ' ' x $stack_depth, "Package $filename.\n" ) if $frame;
6308 # Do we have any breakpoints to put in this file?
6309 return unless $postponed_file{$filename};
6311 # Yes. Mark this file as having breakpoints.
6312 $had_breakpoints{$filename} |= 1;
6314 # "Cannot be done: insufficient magic" - we can't just put the
6315 # breakpoints saved in %postponed_file into %dbline by assigning
6316 # the whole hash; we have to do it one item at a time for the
6317 # breakpoints to be set properly.
6318 #%dbline = %{$postponed_file{$filename}};
6320 # Set the breakpoints, one at a time.
6323 for $key ( keys %{ $postponed_file{$filename} } ) {
6325 # Stash the saved breakpoint into the current file's magic line array.
6326 $dbline{$key} = ${ $postponed_file{$filename} }{$key};
6329 # This file's been compiled; discard the stored breakpoints.
6330 delete $postponed_file{$filename};
6332 } ## end sub postponed
6336 C<dumpit> is the debugger's wrapper around dumpvar.pl.
6338 It gets a filehandle (to which C<dumpvar.pl>'s output will be directed) and
6339 a reference to a variable (the thing to be dumped) as its input.
6341 The incoming filehandle is selected for output (C<dumpvar.pl> is printing to
6342 the currently-selected filehandle, thank you very much). The current
6343 values of the package globals C<$single> and C<$trace> are backed up in
6344 lexicals, and they are turned off (this keeps the debugger from trying
6345 to single-step through C<dumpvar.pl> (I think.)). C<$frame> is localized to
6346 preserve its current value and it is set to zero to prevent entry/exit
6347 messages from printing, and C<$doret> is localized as well and set to -2 to
6348 prevent return values from being shown.
6350 C<dumpit()> then checks to see if it needs to load C<dumpvar.pl> and
6351 tries to load it (note: if you have a C<dumpvar.pl> ahead of the
6352 installed version in C<@INC>, yours will be used instead. Possible security
6355 It then checks to see if the subroutine C<main::dumpValue> is now defined
6356 it should have been defined by C<dumpvar.pl>). If it has, C<dumpit()>
6357 localizes the globals necessary for things to be sane when C<main::dumpValue()>
6358 is called, and picks up the variable to be dumped from the parameter list.
6360 It checks the package global C<%options> to see if there's a C<dumpDepth>
6361 specified. If not, -1 is assumed; if so, the supplied value gets passed on to
6362 C<dumpvar.pl>. This tells C<dumpvar.pl> where to leave off when dumping a
6363 structure: -1 means dump everything.
6365 C<dumpValue()> is then called if possible; if not, C<dumpit()>just prints a
6368 In either case, C<$single>, C<$trace>, C<$frame>, and C<$doret> are restored
6369 and we then return to the caller.
6375 # Save the current output filehandle and switch to the one
6376 # passed in as the first parameter.
6377 my $savout = select(shift);
6379 # Save current settings of $single and $trace, and then turn them off.
6380 my $osingle = $single;
6381 my $otrace = $trace;
6382 $single = $trace = 0;
6384 # XXX Okay, what do $frame and $doret do, again?
6388 # Load dumpvar.pl unless we've already got the sub we need from it.
6389 unless ( defined &main::dumpValue ) {
6390 do 'dumpvar.pl' or die $@;
6393 # If the load succeeded (or we already had dumpvalue()), go ahead
6395 if ( defined &main::dumpValue ) {
6400 my $maxdepth = shift || $option{dumpDepth};
6401 $maxdepth = -1 unless defined $maxdepth; # -1 means infinite depth
6402 main::dumpValue( $v, $maxdepth );
6403 } ## end if (defined &main::dumpValue)
6405 # Oops, couldn't load dumpvar.pl.
6408 print $OUT "dumpvar.pl not available.\n";
6411 # Reset $single and $trace to their old values.
6415 # Restore the old filehandle.
6419 =head2 C<print_trace>
6421 C<print_trace>'s job is to print a stack trace. It does this via the
6422 C<dump_trace> routine, which actually does all the ferreting-out of the
6423 stack trace data. C<print_trace> takes care of formatting it nicely and
6424 printing it to the proper filehandle.
6432 The filehandle to print to.
6436 How many frames to skip before starting trace.
6440 How many frames to print.
6444 A flag: if true, print a I<short> trace without filenames, line numbers, or arguments
6448 The original comment below seems to be noting that the traceback may not be
6449 correct if this routine is called in a tied method.
6453 # Tied method do not create a context, so may get wrong message:
6459 # If this is going to a slave editor, but we're not the primary
6460 # debugger, reset it first.
6462 if $fh eq $LINEINFO # slave editor
6463 and $LINEINFO eq $OUT # normal output
6464 and $term_pid != $$; # not the primary
6466 # Collect the actual trace information to be formatted.
6467 # This is an array of hashes of subroutine call info.
6468 my @sub = dump_trace( $_[0] + 1, $_[1] );
6470 # Grab the "short report" flag from @_.
6471 my $short = $_[2]; # Print short report, next one for sub name
6473 # Run through the traceback info, format it, and print it.
6475 for my $i (0 .. $#sub) {
6477 # Drop out if the user has lost interest and hit control-C.
6480 # Set the separator so arrays print nice.
6483 # Grab and stringify the arguments if they are there.
6485 defined $sub[$i]{args}
6486 ? "(@{ $sub[$i]{args} })"
6489 # Shorten them up if $maxtrace says they're too long.
6490 $args = ( substr $args, 0, $maxtrace - 3 ) . '...'
6491 if length $args > $maxtrace;
6493 # Get the file name.
6494 my $file = $sub[$i]{file};
6496 # Put in a filename header if short is off.
6497 $file = $file eq '-e' ? $file : "file '$file'" unless $short;
6499 # Get the actual sub's name, and shorten to $maxtrace's requirement.
6500 $s = $sub[$i]{'sub'};
6501 $s = ( substr $s, 0, $maxtrace - 3 ) . '...' if length $s > $maxtrace;
6503 # Short report uses trimmed file and sub names.
6505 my $sub = @_ >= 4 ? $_[3] : $s;
6506 print $fh "$sub[$i]{context}=$sub$args from $file:$sub[$i]{line}\n";
6507 } ## end if ($short)
6509 # Non-short report includes full names.
6511 print $fh "$sub[$i]{context} = $s$args"
6512 . " called from $file"
6513 . " line $sub[$i]{line}\n";
6515 } ## end for my $i (0 .. $#sub)
6516 } ## end sub print_trace
6518 =head2 dump_trace(skip[,count])
6520 Actually collect the traceback information available via C<caller()>. It does
6521 some filtering and cleanup of the data, but mostly it just collects it to
6522 make C<print_trace()>'s job easier.
6524 C<skip> defines the number of stack frames to be skipped, working backwards
6525 from the most current. C<count> determines the total number of frames to
6526 be returned; all of them (well, the first 10^9) are returned if C<count>
6529 This routine returns a list of hashes, from most-recent to least-recent
6530 stack frame. Each has the following keys and values:
6534 =item * C<context> - C<.> (null), C<$> (scalar), or C<@> (array)
6536 =item * C<sub> - subroutine name, or C<eval> information
6538 =item * C<args> - undef, or a reference to an array of arguments
6540 =item * C<file> - the file in which this item was defined (if any)
6542 =item * C<line> - the line on which it was defined
6548 sub _dump_trace_calc_saved_single_arg
6550 my ($nothard, $arg) = @_;
6553 if ( not defined $arg ) { # undefined parameter
6557 elsif ( $nothard and tied $arg ) { # tied parameter
6560 elsif ( $nothard and $type = ref $arg ) { # reference
6561 return "ref($type)";
6563 else { # can be stringified
6565 "$arg"; # Safe to stringify now - should not call f().
6567 # Backslash any single-quotes or backslashes.
6570 # Single-quote it unless it's a number or a colon-separated
6573 unless /^(?: -?[\d.]+ | \*[\w:]* )$/x;
6575 # Turn high-bit characters into meta-whatever, and controls into like
6577 require 'meta_notation.pm';
6578 $_ = _meta_notation($_) if /[[:^print:]]/a;
6584 sub _dump_trace_calc_save_args {
6588 map { _dump_trace_calc_saved_single_arg($nothard, $_) } @args
6594 # How many levels to skip.
6597 # How many levels to show. (1e9 is a cheap way of saying "all of them";
6598 # it's unlikely that we'll have more than a billion stack frames. If you
6599 # do, you've got an awfully big machine...)
6600 my $count = shift || 1e9;
6602 # We increment skip because caller(1) is the first level *back* from
6603 # the current one. Add $skip to the count of frames so we have a
6604 # simple stop criterion, counting from $skip to $count+$skip.
6608 # These variables are used to capture output from caller();
6609 my ( $p, $file, $line, $sub, $h, $context );
6611 my ( $e, $r, @sub, $args );
6613 # XXX Okay... why'd we do that?
6614 my $nothard = not $frame & 8;
6617 # Do not want to trace this.
6618 my $otrace = $trace;
6621 # Start out at the skip count.
6622 # If we haven't reached the number of frames requested, and caller() is
6623 # still returning something, stay in the loop. (If we pass the requested
6624 # number of stack frames, or we run out - caller() returns nothing - we
6626 # Up the stack frame index to go back one more level each time.
6630 and ( $p, $file, $line, $sub, $h, $context, $e, $r ) = caller($i) ;
6634 # if the sub has args ($h true), make an anonymous array of the
6636 my $args = $h ? _dump_trace_calc_save_args($nothard) : undef;
6638 # If context is true, this is array (@)context.
6639 # If context is false, this is scalar ($) context.
6640 # If neither, context isn't defined. (This is apparently a 'can't
6642 $context = $context ? '@' : ( defined $context ? "\$" : '.' );
6644 # remove trailing newline-whitespace-semicolon-end of line sequence
6645 # from the eval text, if any.
6646 $e =~ s/\n\s*\;\s*\Z// if $e;
6648 # Escape backslashed single-quotes again if necessary.
6649 $e =~ s/([\\\'])/\\$1/g if $e;
6651 # if the require flag is true, the eval text is from a require.
6653 $sub = "require '$e'";
6656 # if it's false, the eval text is really from an eval.
6657 elsif ( defined $r ) {
6661 # If the sub is '(eval)', this is a block eval, meaning we don't
6662 # know what the eval'ed text actually was.
6663 elsif ( $sub eq '(eval)' ) {
6664 $sub = "eval {...}";
6667 # Stick the collected information into @sub as an anonymous hash.
6671 context => $context,
6679 # Stop processing frames if the user hit control-C.
6681 } ## end for ($i = $skip ; $i < ...
6683 # Restore the trace value again.
6686 } ## end sub dump_trace
6690 C<action()> takes input provided as the argument to an add-action command,
6691 either pre- or post-, and makes sure it's a complete command. It doesn't do
6692 any fancy parsing; it just keeps reading input until it gets a string
6693 without a trailing backslash.
6700 while ( $action =~ s/\\$// ) {
6702 # We have a backslash on the end. Read more.
6704 } ## end while ($action =~ s/\\$//)
6706 # Return the assembled action.
6712 This routine mostly just packages up a regular expression to be used
6713 to check that the thing it's being matched against has properly-matched
6716 Of note is the definition of the C<$balanced_brace_re> global via C<||=>, which
6717 speeds things up by only creating the qr//'ed expression once; if it's
6718 already defined, we don't try to define it again. A speed hack.
6722 use vars qw($balanced_brace_re);
6726 # I hate using globals!
6727 $balanced_brace_re ||= qr{
6730 (?> [^{}] + ) # Non-parens without backtracking
6732 (??{ $balanced_brace_re }) # Group with matching parens
6736 return $_[0] !~ m/$balanced_brace_re/;
6737 } ## end sub unbalanced
6741 C<gets()> is a primitive (very primitive) routine to read continuations.
6742 It was devised for reading continuations for actions.
6743 it just reads more input with C<readline()> and returns it.
6748 return DB::readline("cont: ");
6751 =head2 C<_db_system()> - handle calls to<system()> without messing up the debugger
6753 The C<system()> function assumes that it can just go ahead and use STDIN and
6754 STDOUT, but under the debugger, we want it to use the debugger's input and
6757 C<_db_system()> socks away the program's STDIN and STDOUT, and then substitutes
6758 the debugger's IN and OUT filehandles for them. It does the C<system()> call,
6759 and then puts everything back again.
6765 # We save, change, then restore STDIN and STDOUT to avoid fork() since
6766 # some non-Unix systems can do system() but have problems with fork().
6767 open( SAVEIN, "<&STDIN" ) || _db_warn("Can't save STDIN");
6768 open( SAVEOUT, ">&STDOUT" ) || _db_warn("Can't save STDOUT");
6769 open( STDIN, "<&IN" ) || _db_warn("Can't redirect STDIN");
6770 open( STDOUT, ">&OUT" ) || _db_warn("Can't redirect STDOUT");
6772 # XXX: using csh or tcsh destroys sigint retvals!
6774 open( STDIN, "<&SAVEIN" ) || _db_warn("Can't restore STDIN");
6775 open( STDOUT, ">&SAVEOUT" ) || _db_warn("Can't restore STDOUT");
6779 # most of the $? crud was coping with broken cshisms
6781 _db_warn( "(Command exited ", ( $? >> 8 ), ")\n" );
6785 "(Command died of SIG#",
6787 ( ( $? & 128 ) ? " -- core dumped" : "" ),
6796 *system = \&_db_system;
6798 =head1 TTY MANAGEMENT
6800 The subs here do some of the terminal management for multiple debuggers.
6804 Top-level function called when we want to set up a new terminal for use
6807 If the C<noTTY> debugger option was set, we'll either use the terminal
6808 supplied (the value of the C<noTTY> option), or we'll use C<Term::Rendezvous>
6809 to find one. If we're a forked debugger, we call C<resetterm> to try to
6810 get a whole new terminal if we can.
6812 In either case, we set up the terminal next. If the C<ReadLine> option was
6813 true, we'll get a C<Term::ReadLine> object for the current terminal and save
6814 the appropriate attributes. We then
6818 use vars qw($ornaments);
6819 use vars qw($rl_attribs);
6823 # Load Term::Readline, but quietly; don't debug it and don't trace it.
6826 require Term::ReadLine;
6828 # If noTTY is set, but we have a TTY name, go ahead and hook up to it.
6831 my ( $i, $o ) = split $tty, /,/;
6832 $o = $i unless defined $o;
6833 open( IN, '<', $i ) or die "Cannot open TTY '$i' for read: $!";
6834 open( OUT, '>', $o ) or die "Cannot open TTY '$o' for write: $!";
6840 # We don't have a TTY - try to find one via Term::Rendezvous.
6842 require Term::Rendezvous;
6844 # See if we have anything to pass to Term::Rendezvous.
6845 # Use $HOME/.perldbtty$$ if not.
6846 my $rv = $ENV{PERLDB_NOTTY} || "$ENV{HOME}/.perldbtty$$";
6848 # Rendezvous and get the filehandles.
6849 my $term_rv = Term::Rendezvous->new( $rv );
6851 $OUT = $term_rv->OUT;
6852 } ## end else [ if ($tty)
6853 } ## end if ($notty)
6855 # We're a daughter debugger. Try to fork off another TTY.
6856 if ( $term_pid eq '-1' ) { # In a TTY with another debugger
6860 # If we shouldn't use Term::ReadLine, don't.
6862 $term = Term::ReadLine::Stub->new( 'perldb', $IN, $OUT );
6865 # We're using Term::ReadLine. Get all the attributes for this terminal.
6867 $term = Term::ReadLine->new( 'perldb', $IN, $OUT );
6869 $rl_attribs = $term->Attribs;
6870 $rl_attribs->{basic_word_break_characters} .= '-:+/*,[])}'
6871 if defined $rl_attribs->{basic_word_break_characters}
6872 and index( $rl_attribs->{basic_word_break_characters}, ":" ) == -1;
6873 $rl_attribs->{special_prefixes} = '$@&%';
6874 $rl_attribs->{completer_word_break_characters} .= '$@&%';
6875 $rl_attribs->{completion_function} = \&db_complete;
6876 } ## end else [ if (!$rl)
6878 # Set up the LINEINFO filehandle.
6879 $LINEINFO = $OUT unless defined $LINEINFO;
6880 $lineinfo = $console unless defined $lineinfo;
6886 if ( $term->Features->{setHistory} and "@hist" ne "?" ) {
6887 $term->SetHistory(@hist);
6890 # XXX Ornaments are turned on unconditionally, which is not
6891 # always a good thing.
6892 ornaments($ornaments) if defined $ornaments;
6894 } ## end sub setterm
6897 $histfile //= option_val("HistFile", undef);
6898 return unless defined $histfile;
6899 open my $fh, "<", $histfile or return;
6910 return unless defined $histfile;
6911 eval { require File::Path } or return;
6912 eval { require File::Basename } or return;
6913 File::Path::mkpath(File::Basename::dirname($histfile));
6914 open my $fh, ">", $histfile or die "Could not open '$histfile': $!";
6915 $histsize //= option_val("HistSize",100);
6916 my @copy = grep { $_ ne '?' } @hist;
6917 my $start = scalar(@copy) > $histsize ? scalar(@copy)-$histsize : 0;
6918 for ($start .. $#copy) {
6919 print $fh "$copy[$_]\n";
6921 close $fh or die "Could not write '$histfile': $!";
6924 =head1 GET_FORK_TTY EXAMPLE FUNCTIONS
6926 When the process being debugged forks, or the process invokes a command
6927 via C<system()> which starts a new debugger, we need to be able to get a new
6928 C<IN> and C<OUT> filehandle for the new debugger. Otherwise, the two processes
6929 fight over the terminal, and you can never quite be sure who's going to get the
6930 input you're typing.
6932 C<get_fork_TTY> is a glob-aliased function which calls the real function that
6933 is tasked with doing all the necessary operating system mojo to get a new
6934 TTY (and probably another window) and to direct the new debugger to read and
6937 The debugger provides C<get_fork_TTY> functions which work for TCP
6938 socket servers, X11, OS/2, and Mac OS X. Other systems are not
6939 supported. You are encouraged to write C<get_fork_TTY> functions which
6940 work for I<your> platform and contribute them.
6942 =head3 C<socket_get_fork_TTY>
6946 sub connect_remoteport {
6949 my $socket = IO::Socket::INET->new(
6951 PeerAddr => $remoteport,
6955 die "Unable to connect to remote host: $remoteport\n";
6960 sub socket_get_fork_TTY {
6961 $tty = $LINEINFO = $IN = $OUT = connect_remoteport();
6963 # Do I need to worry about setting $term?
6965 reset_IN_OUT( $IN, $OUT );
6969 =head3 C<xterm_get_fork_TTY>
6971 This function provides the C<get_fork_TTY> function for X11. If a
6972 program running under the debugger forks, a new <xterm> window is opened and
6973 the subsidiary debugger is directed there.
6975 The C<open()> call is of particular note here. We have the new C<xterm>
6976 we're spawning route file number 3 to STDOUT, and then execute the C<tty>
6977 command (which prints the device name of the TTY we'll want to use for input
6978 and output to STDOUT, then C<sleep> for a very long time, routing this output
6979 to file number 3. This way we can simply read from the <XT> filehandle (which
6980 is STDOUT from the I<commands> we ran) to get the TTY we want to use.
6982 Only works if C<xterm> is in your path and C<$ENV{DISPLAY}>, etc. are
6987 sub xterm_get_fork_TTY {
6988 ( my $name = $0 ) =~ s,^.*[/\\],,s;
6990 qq[3>&1 xterm -title "Daughter Perl debugger $pids $name" -e sh -c 'tty 1>&3;\
6993 # Get the output from 'tty' and clean it up a little.
6997 $pidprompt = ''; # Shown anyway in titlebar
6999 # We need $term defined or we can not switch to the newly created xterm
7000 if ($tty ne '' && !defined $term) {
7001 require Term::ReadLine;
7003 $term = Term::ReadLine::Stub->new( 'perldb', $IN, $OUT );
7006 $term = Term::ReadLine->new( 'perldb', $IN, $OUT );
7009 # There's our new TTY.
7011 } ## end sub xterm_get_fork_TTY
7013 =head3 C<os2_get_fork_TTY>
7015 XXX It behooves an OS/2 expert to write the necessary documentation for this!
7019 # This example function resets $IN, $OUT itself
7021 sub os2_get_fork_TTY { # A simplification of the following (and works without):
7023 ( my $name = $0 ) =~ s,^.*[/\\],,s;
7024 my %opt = ( title => "Daughter Perl debugger $pids $name",
7025 ($rl ? (read_by_key => 1) : ()) );
7026 require OS2::Process;
7027 my ($in, $out, $pid) = eval { OS2::Process::io_term(related => 0, %opt) }
7029 $pidprompt = ''; # Shown anyway in titlebar
7030 reset_IN_OUT($in, $out);
7032 return ''; # Indicate that reset_IN_OUT is called
7033 } ## end sub os2_get_fork_TTY
7035 =head3 C<macosx_get_fork_TTY>
7037 The Mac OS X version uses AppleScript to tell Terminal.app to create
7042 # Notes about Terminal.app's AppleScript support,
7043 # (aka things that might break in future OS versions).
7045 # The "do script" command doesn't return a reference to the new window
7046 # it creates, but since it appears frontmost and windows are enumerated
7047 # front to back, we can use "first window" === "window 1".
7049 # Since "do script" is implemented by supplying the argument (plus a
7050 # return character) as terminal input, there's a potential race condition
7051 # where the debugger could beat the shell to reading the command.
7052 # To prevent this, we wait for the screen to clear before proceeding.
7055 # There's no direct accessor for the tty device name, so we fiddle
7056 # with the window title options until it says what we want.
7059 # There _is_ a direct accessor for the tty device name, _and_ there's
7060 # a new possible component of the window title (the name of the settings
7061 # set). A separate version is needed.
7063 my @script_versions=
7065 ([237, <<'__LEOPARD__'],
7066 tell application "Terminal"
7067 do script "clear;exec sleep 100000"
7068 tell first tab of first window
7070 set custom title to "forked perl debugger"
7071 set title displays custom title to true
7072 repeat while (length of first paragraph of (get contents)) > 0
7080 [100, <<'__JAGUAR_TIGER__'],
7081 tell application "Terminal"
7082 do script "clear;exec sleep 100000"
7084 set title displays shell path to false
7085 set title displays window size to false
7086 set title displays file name to false
7087 set title displays device name to true
7088 set title displays custom title to true
7089 set custom title to ""
7090 copy "/dev/" & name to thetty
7091 set custom title to "forked perl debugger"
7092 repeat while (length of first paragraph of (get contents)) > 0
7102 sub macosx_get_fork_TTY
7104 my($version,$script,$pipe,$tty);
7106 return unless $version=$ENV{TERM_PROGRAM_VERSION};
7107 foreach my $entry (@script_versions) {
7108 if ($version>=$entry->[0]) {
7109 $script=$entry->[1];
7113 return unless defined($script);
7114 return unless open($pipe,'-|','/usr/bin/osascript','-e',$script);
7115 $tty=readline($pipe);
7117 return unless defined($tty) && $tty =~ m(^/dev/);
7122 =head3 C<tmux_get_fork_TTY>
7124 Creates a split window for subprocesses when a process running under the
7125 perl debugger in Tmux forks.
7129 sub tmux_get_fork_TTY {
7130 return unless $ENV{TMUX};
7134 my $status = open $pipe, '-|', 'tmux', 'split-window',
7135 '-P', '-F', '#{pane_tty}', 'sleep 100000';
7147 if ( !defined $term ) {
7148 require Term::ReadLine;
7150 $term = Term::ReadLine::Stub->new( 'perldb', $IN, $OUT );
7153 $term = Term::ReadLine->new( 'perldb', $IN, $OUT );
7161 =head2 C<create_IN_OUT($flags)>
7163 Create a new pair of filehandles, pointing to a new TTY. If impossible,
7164 try to diagnose why.
7170 =item * 1 - Don't know how to create a new TTY.
7172 =item * 2 - Debugger has forked, but we can't get a new TTY.
7174 =item * 4 - standard debugger startup is happening.
7180 use vars qw($fork_TTY);
7182 sub create_IN_OUT { # Create a window with IN/OUT handles redirected there
7184 # If we know how to get a new TTY, do it! $in will have
7185 # the TTY name if get_fork_TTY works.
7186 my $in = get_fork_TTY(@_) if defined &get_fork_TTY;
7188 # It used to be that
7189 $in = $fork_TTY if defined $fork_TTY; # Backward compatibility
7191 if ( not defined $in ) {
7194 # We don't know how.
7195 print_help(<<EOP) if $why == 1;
7196 I<#########> Forked, but do not know how to create a new B<TTY>. I<#########>
7200 print_help(<<EOP) if $why == 2;
7201 I<#########> Daughter session, do not know how to change a B<TTY>. I<#########>
7202 This may be an asynchronous session, so the parent debugger may be active.
7205 # Note that both debuggers are fighting over the same input.
7206 print_help(<<EOP) if $why != 4;
7207 Since two debuggers fight for the same TTY, input is severely entangled.
7211 I know how to switch the output to a different window in xterms, OS/2
7212 consoles, and Mac OS X Terminal.app only. For a manual switch, put the name
7213 of the created I<TTY> in B<\$DB::fork_TTY>, or define a function
7214 B<DB::get_fork_TTY()> returning this.
7216 On I<UNIX>-like systems one can get the name of a I<TTY> for the given window
7217 by typing B<tty>, and disconnect the I<shell> from I<TTY> by B<sleep 1000000>.
7220 } ## end if (not defined $in)
7221 elsif ( $in ne '' ) {
7225 $console = ''; # Indicate no need to open-from-the-console
7228 } ## end sub create_IN_OUT
7232 Handles rejiggering the prompt when we've forked off a new debugger.
7234 If the new debugger happened because of a C<system()> that invoked a
7235 program under the debugger, the arrow between the old pid and the new
7236 in the prompt has I<two> dashes instead of one.
7238 We take the current list of pids and add this one to the end. If there
7239 isn't any list yet, we make one up out of the initial pid associated with
7240 the terminal and our new pid, sticking an arrow (either one-dashed or
7241 two dashed) in between them.
7243 If C<CreateTTY> is off, or C<resetterm> was called with no arguments,
7244 we don't try to create a new IN and OUT filehandle. Otherwise, we go ahead
7249 sub resetterm { # We forked, so we need a different TTY
7251 # Needs to be passed to create_IN_OUT() as well.
7254 # resetterm(2): got in here because of a system() starting a debugger.
7255 # resetterm(1): just forked.
7256 my $systemed = $in > 1 ? '-' : '';
7258 # If there's already a list of pids, add this to the end.
7260 $pids =~ s/\]/$systemed->$$]/;
7263 # No pid list. Time to make one.
7265 $pids = "[$term_pid->$$]";
7268 # The prompt we're going to be using for this debugger.
7271 # We now 0wnz this terminal.
7274 # Just return if we're not supposed to try to create a new TTY.
7275 return unless $CreateTTY & $in;
7277 # Try to create a new IN/OUT pair.
7279 } ## end sub resetterm
7283 First, we handle stuff in the typeahead buffer. If there is any, we shift off
7284 the next line, print a message saying we got it, add it to the terminal
7285 history (if possible), and return it.
7287 If there's nothing in the typeahead buffer, check the command filehandle stack.
7288 If there are any filehandles there, read from the last one, and return the line
7289 if we got one. If not, we pop the filehandle off and close it, and try the
7290 next one up the stack.
7292 If we've emptied the filehandle stack, we check to see if we've got a socket
7293 open, and we read that and return it if we do. If we don't, we just call the
7294 core C<readline()> and return its value.
7300 # Localize to prevent it from being smashed in the program being debugged.
7303 # If there are stacked filehandles to read from ...
7304 # (Handle it before the typeahead, because we may call source/etc. from
7308 # Read from the last one in the stack.
7309 my $line = CORE::readline( $cmdfhs[-1] );
7311 # If we got a line ...
7313 ? ( print $OUT ">> $line" and return $line ) # Echo and return
7314 : close pop @cmdfhs; # Pop and close
7315 } ## end while (@cmdfhs)
7317 # Pull a line out of the typeahead if there's stuff there.
7320 # How many lines left.
7321 my $left = @typeahead;
7323 # Get the next line.
7324 my $got = shift @typeahead;
7326 # Print a message saying we got input from the typeahead.
7328 print $OUT "auto(-$left)", shift, $got, "\n";
7330 # Add it to the terminal history (if possible).
7331 $term->AddHistory($got)
7333 and defined $term->Features->{addHistory};
7335 } ## end if (@typeahead)
7337 # We really need to read some input. Turn off entry/exit trace and
7338 # return value printing.
7342 # Nothing on the filehandle stack. Socket?
7343 if ( ref $OUT and UNIVERSAL::isa( $OUT, 'IO::Socket::INET' ) ) {
7345 # Send anything we have to send.
7346 $OUT->write( join( '', @_ ) );
7348 # Receive anything there is to receive.
7353 while ($first_time or (length($buf) && ($stuff .= $buf) !~ /\n/))
7356 $IN->recv( $buf = '', 2048 ); # XXX "what's wrong with sysread?"
7357 # XXX Don't know. You tell me.
7362 } ## end if (ref $OUT and UNIVERSAL::isa...
7364 # No socket. Just read from the terminal.
7366 return $term->readline(@_);
7368 } ## end sub readline
7370 =head1 OPTIONS SUPPORT ROUTINES
7372 These routines handle listing and setting option values.
7374 =head2 C<dump_option> - list the current value of an option setting
7376 This routine uses C<option_val> to look up the value for an option.
7377 It cleans up escaped single-quotes and then displays the option and
7383 my ( $opt, $val ) = @_;
7384 $val = option_val( $opt, 'N/A' );
7385 $val =~ s/([\\\'])/\\$1/g;
7386 printf $OUT "%20s = '%s'\n", $opt, $val;
7387 } ## end sub dump_option
7389 sub options2remember {
7390 foreach my $k (@RememberOnROptions) {
7391 $option{$k} = option_val( $k, 'N/A' );
7396 =head2 C<option_val> - find the current value of an option
7398 This can't just be a simple hash lookup because of the indirect way that
7399 the option values are stored. Some are retrieved by calling a subroutine,
7400 some are just variables.
7402 You must supply a default value to be used in case the option isn't set.
7407 my ( $opt, $default ) = @_;
7410 # Does this option exist, and is it a variable?
7411 # If so, retrieve the value via the value in %optionVars.
7412 if ( defined $optionVars{$opt}
7413 and defined ${ $optionVars{$opt} } )
7415 $val = ${ $optionVars{$opt} };
7418 # Does this option exist, and it's a subroutine?
7419 # If so, call the subroutine via the ref in %optionAction
7420 # and capture the value.
7421 elsif ( defined $optionAction{$opt}
7422 and defined &{ $optionAction{$opt} } )
7424 $val = &{ $optionAction{$opt} }();
7427 # If there's an action or variable for the supplied option,
7428 # but no value was set, use the default.
7429 elsif (defined $optionAction{$opt} and not defined $option{$opt}
7430 or defined $optionVars{$opt} and not defined ${ $optionVars{$opt} } )
7435 # Otherwise, do the simple hash lookup.
7437 $val = $option{$opt};
7440 # If the value isn't defined, use the default.
7441 # Then return whatever the value is.
7442 $val = $default unless defined $val;
7444 } ## end sub option_val
7446 =head2 C<parse_options>
7448 Handles the parsing and execution of option setting/displaying commands.
7450 An option entered by itself is assumed to be I<set me to 1> (the default value)
7451 if the option is a boolean one. If not, the user is prompted to enter a valid
7452 value or to query the current value (via C<option? >).
7454 If C<option=value> is entered, we try to extract a quoted string from the
7455 value (if it is quoted). If it's not, we just use the whole value as-is.
7457 We load any modules required to service this option, and then we set it: if
7458 it just gets stuck in a variable, we do that; if there's a subroutine to
7459 handle setting the option, we call that.
7461 Finally, if we're running in interactive mode, we display the effect of the
7462 user's command back to the terminal, skipping this if we're setting things
7463 during initialization.
7473 # These options need a value. Don't allow them to be clobbered by accident.
7474 my %opt_needs_val = map { ( $_ => 1 ) } qw{
7475 dumpDepth arrayDepth hashDepth LineInfo maxTraceLen ornaments windowSize
7476 pager quote ReadLine recallCommand RemotePort ShellBang TTY CommandSet
7479 while (length($s)) {
7482 # Clean off excess leading whitespace.
7483 $s =~ s/^\s+// && next;
7485 # Options are always all word characters, followed by a non-word
7487 if ($s !~ s/^(\w+)(\W?)//) {
7488 print {$OUT} "Invalid option '$s'\n";
7491 my ( $opt, $sep ) = ( $1, $2 );
7493 # Make sure that such an option exists.
7494 my $matches = ( grep { /^\Q$opt/ && ( $option = $_ ) } @options )
7495 || ( grep { /^\Q$opt/i && ( $option = $_ ) } @options );
7498 print {$OUT} "Unknown option '$opt'\n";
7502 print {$OUT} "Ambiguous option '$opt'\n";
7507 # '?' as separator means query, but must have whitespace after it.
7508 if ( "?" eq $sep ) {
7510 print {$OUT} "Option query '$opt?' followed by non-space '$s'\n" ;
7515 #&dump_option($opt);
7516 } ## end if ("?" eq $sep)
7518 # Separator is whitespace (or just a carriage return).
7519 # They're going for a default, which we assume is 1.
7520 elsif ( $sep !~ /\S/ ) {
7522 $val = "1"; # this is an evil default; make 'em set it!
7525 # Separator is =. Trying to set a value.
7526 elsif ( $sep eq "=" ) {
7528 # If quoted, extract a quoted string.
7529 if ($s =~ s/ (["']) ( (?: \\. | (?! \1 ) [^\\] )* ) \1 //x) {
7531 ( $val = $2 ) =~ s/\\([$quote\\])/$1/g;
7534 # Not quoted. Use the whole thing. Warn about 'option='.
7538 print OUT qq(Option better cleared using $opt=""\n)
7540 } ## end else [ if (s/ (["']) ( (?: \\. | (?! \1 ) [^\\] )* ) \1 //x)
7542 } ## end elsif ($sep eq "=")
7544 # "Quoted" with [], <>, or {}.
7545 else { #{ to "let some poor schmuck bounce on the % key in B<vi>."
7547 "\\" . substr( ")]>}$sep", index( "([<{", $sep ), 1 ); #}
7548 $s =~ s/^(([^\\$end]|\\[\\$end])*)$end($|\s+)//
7549 or print( $OUT "Unclosed option value '$opt$sep$_'\n" ), last;
7550 ( $val = $1 ) =~ s/\\([\\$end])/$1/g;
7551 } ## end else [ if ("?" eq $sep)
7553 # Exclude non-booleans from getting set to 1 by default.
7554 if ( $opt_needs_val{$option} && $val_defaulted ) {
7555 my $cmd = ( $CommandSet eq '580' ) ? 'o' : 'O';
7557 "Option '$opt' is non-boolean. Use '$cmd $option=VAL' to set, '$cmd $option?' to query\n";
7559 } ## end if ($opt_needs_val{$option...
7561 # Save the option value.
7562 $option{$option} = $val if defined $val;
7564 # Load any module that this option requires.
7565 if ( defined($optionRequire{$option}) && defined($val) ) {
7569 require '$optionRequire{$option}';
7571 } || die $@ # XXX: shouldn't happen
7575 # Stick it in the proper variable if it goes in a variable.
7576 if (defined($optionVars{$option}) && defined($val)) {
7577 ${ $optionVars{$option} } = $val;
7580 # Call the appropriate sub if it gets set via sub.
7581 if (defined($optionAction{$option})
7582 && defined (&{ $optionAction{$option} })
7585 &{ $optionAction{$option} }($val);
7588 # Not initialization - echo the value we set it to.
7589 dump_option($option) if ($OUT ne \*STDERR);
7590 } ## end while (length)
7591 } ## end sub parse_options
7593 =head1 RESTART SUPPORT
7595 These routines are used to store (and restore) lists of items in environment
7596 variables during a restart.
7600 Set_list packages up items to be stored in a set of environment variables
7601 (VAR_n, containing the number of items, and VAR_0, VAR_1, etc., containing
7602 the values). Values outside the standard ASCII charset are stored by encoding
7603 them as hexadecimal values.
7608 my ( $stem, @list ) = @_;
7611 # VAR_n: how many we have. Scalar assignment gets the number of items.
7612 $ENV{"${stem}_n"} = @list;
7614 # Grab each item in the list, escape the backslashes, encode the non-ASCII
7615 # as hex, and then save in the appropriate VAR_0, VAR_1, etc.
7616 for my $i ( 0 .. $#list ) {
7618 $val =~ s/\\/\\\\/g;
7619 no warnings 'experimental::regex_sets';
7620 $val =~ s/ ( (?[ [\000-\xFF] & [:^print:] ]) ) /
7621 "\\0x" . unpack('H2',$1)/xaeg;
7622 $ENV{"${stem}_$i"} = $val;
7623 } ## end for $i (0 .. $#list)
7624 } ## end sub set_list
7628 Reverse the set_list operation: grab VAR_n to see how many we should be getting
7629 back, and then pull VAR_0, VAR_1. etc. back out.
7636 my $n = delete $ENV{"${stem}_n"};
7638 for my $i ( 0 .. $n - 1 ) {
7639 $val = delete $ENV{"${stem}_$i"};
7640 $val =~ s/\\((\\)|0x(..))/ $2 ? $2 : pack('H2', $3) /ge;
7644 } ## end sub get_list
7646 =head1 MISCELLANEOUS SIGNAL AND I/O MANAGEMENT
7650 The C<catch()> subroutine is the essence of fast and low-impact. We simply
7651 set an already-existing global scalar variable to a constant value. This
7652 avoids allocating any memory possibly in the middle of something that will
7653 get all confused if we do, particularly under I<unsafe signals>.
7659 return; # Put nothing on the stack - malloc/free land!
7664 C<warn> emits a warning, by joining together its arguments and printing
7665 them, with couple of fillips.
7667 If the composited message I<doesn't> end with a newline, we automatically
7668 add C<$!> and a newline to the end of the message. The subroutine expects $OUT
7669 to be set to the filehandle to be used to output warnings; it makes no
7670 assumptions about what filehandles are available.
7675 my ($msg) = join( "", @_ );
7676 $msg .= ": $!\n" unless $msg =~ /\n$/;
7683 =head1 INITIALIZATION TTY SUPPORT
7685 =head2 C<reset_IN_OUT>
7687 This routine handles restoring the debugger's input and output filehandles
7688 after we've tried and failed to move them elsewhere. In addition, it assigns
7689 the debugger's output filehandle to $LINEINFO if it was already open there.
7694 my $switch_li = $LINEINFO eq $OUT;
7696 # If there's a term and it's able to get a new tty, try to get one.
7697 if ( $term and $term->Features->{newTTY} ) {
7698 ( $IN, $OUT ) = ( shift, shift );
7699 $term->newTTY( $IN, $OUT );
7702 # This term can't get a new tty now. Better luck later.
7704 _db_warn("Too late to set IN/OUT filehandles, enabled on next 'R'!\n");
7707 # Set the filehndles up as they were.
7709 ( $IN, $OUT ) = ( shift, shift );
7712 # Unbuffer the output filehandle.
7715 # Point LINEINFO to the same output filehandle if it was there before.
7716 $LINEINFO = $OUT if $switch_li;
7717 } ## end sub reset_IN_OUT
7719 =head1 OPTION SUPPORT ROUTINES
7721 The following routines are used to process some of the more complicated
7726 Sets the input and output filehandles to the specified files or pipes.
7727 If the terminal supports switching, we go ahead and do it. If not, and
7728 there's already a terminal in place, we save the information to take effect
7731 If there's no terminal yet (for instance, during debugger initialization),
7732 we go ahead and set C<$console> and C<$tty> to the file indicated.
7738 if ( @_ and $term and $term->Features->{newTTY} ) {
7740 # This terminal supports switching to a new TTY.
7741 # Can be a list of two files, or on string containing both names,
7743 # XXX Should this perhaps be an assignment from @_?
7744 my ( $in, $out ) = shift;
7747 # Split list apart if supplied.
7748 ( $in, $out ) = split /,/, $in, 2;
7752 # Use the same file for both input and output.
7756 # Open file onto the debugger's filehandles, if you can.
7757 open IN, '<', $in or die "cannot open '$in' for read: $!";
7758 open OUT, '>', $out or die "cannot open '$out' for write: $!";
7760 # Swap to the new filehandles.
7761 reset_IN_OUT( \*IN, \*OUT );
7763 # Save the setting for later.
7765 } ## end if (@_ and $term and $term...
7767 # Terminal doesn't support new TTY, or doesn't support readline.
7768 # Can't do it now, try restarting.
7770 _db_warn("Too late to set TTY, enabled on next 'R'!\n");
7773 # Useful if done through PERLDB_OPTS:
7774 $console = $tty = shift if @_;
7776 # Return whatever the TTY is.
7782 Sets the C<$notty> global, controlling whether or not the debugger tries to
7783 get a terminal to read from. If called after a terminal is already in place,
7784 we save the value to use it if we're restarted.
7790 _db_warn("Too late to set noTTY, enabled on next 'R'!\n") if @_;
7792 $notty = shift if @_;
7798 Sets the C<$rl> option variable. If 0, we use C<Term::ReadLine::Stub>
7799 (essentially, no C<readline> processing on this I<terminal>). Otherwise, we
7800 use C<Term::ReadLine>. Can't be changed after a terminal's in place; we save
7801 the value in case a restart is done so we can change it then.
7807 _db_warn("Too late to set ReadLine, enabled on next 'R'!\n") if @_;
7811 } ## end sub ReadLine
7813 =head2 C<RemotePort>
7815 Sets the port that the debugger will try to connect to when starting up.
7816 If the terminal's already been set up, we can't do it, but we remember the
7817 setting in case the user does a restart.
7823 _db_warn("Too late to set RemotePort, enabled on next 'R'!\n") if @_;
7825 $remoteport = shift if @_;
7827 } ## end sub RemotePort
7831 Checks with the terminal to see if C<Tk> is running, and returns true or
7832 false. Returns false if the current terminal doesn't support C<readline>.
7837 if ( ${ $term->Features }{tkRunning} ) {
7838 return $term->tkRunning(@_);
7842 print $OUT "tkRunning not supported by current ReadLine package.\n";
7845 } ## end sub tkRunning
7849 Sets nonstop mode. If a terminal's already been set up, it's too late; the
7850 debugger remembers the setting in case you restart, though.
7856 _db_warn("Too late to set up NonStop mode, enabled on next 'R'!\n")
7859 $runnonstop = shift if @_;
7861 } ## end sub NonStop
7865 _db_warn("Some flag changes could not take effect until next 'R'!\n")
7868 $^P = parse_DollarCaretP_flags(shift) if @_;
7869 expand_DollarCaretP_flags($^P);
7874 Set up the C<$pager> variable. Adds a pipe to the front unless there's one
7882 $pager = "|" . $pager unless $pager =~ /^(\+?\>|\|)/;
7889 Sets the shell escape command, and generates a printable copy to be used
7896 # If we got an argument, meta-quote it, and add '\b' if it
7897 # ends in a word character.
7899 $sh = quotemeta shift;
7900 $sh .= "\\b" if $sh =~ /\w$/;
7903 # Generate the printable version for the help:
7904 $psh = $sh; # copy it
7905 $psh =~ s/\\b$//; # Take off trailing \b if any
7906 $psh =~ s/\\(.)/$1/g; # De-escape
7907 $psh; # return the printable version
7908 } ## end sub shellBang
7912 If the terminal has its own ornaments, fetch them. Otherwise accept whatever
7913 was passed as the argument. (This means you can't override the terminal's
7919 if ( defined $term ) {
7921 # We don't want to show warning backtraces, but we do want die() ones.
7922 local $warnLevel = 0;
7923 local $dieLevel = 1;
7925 # No ornaments if the terminal doesn't support them.
7926 if (not $term->Features->{ornaments}) {
7930 return (eval { $term->ornaments(@_) } || '');
7933 # Use what was passed in if we can't determine it ourselves.
7940 } ## end sub ornaments
7942 =head2 C<recallCommand>
7944 Sets the recall command, and builds a printable version which will appear in
7951 # If there is input, metaquote it. Add '\b' if it ends with a word
7954 $rc = quotemeta shift;
7955 $rc .= "\\b" if $rc =~ /\w$/;
7958 # Build it into a printable version.
7959 $prc = $rc; # Copy it
7960 $prc =~ s/\\b$//; # Remove trailing \b
7961 $prc =~ s/\\(.)/$1/g; # Remove escapes
7962 return $prc; # Return the printable version
7963 } ## end sub recallCommand
7965 =head2 C<LineInfo> - where the line number information goes
7967 Called with no arguments, returns the file or pipe that line info should go to.
7969 Called with an argument (a file or a pipe), it opens that onto the
7970 C<LINEINFO> filehandle, unbuffers the filehandle, and then returns the
7971 file or pipe again to the caller.
7979 # If this is a valid "thing to be opened for output", tack a
7980 # '>' onto the front.
7981 my $stream = ( $lineinfo =~ /^(\+?\>|\|)/ ) ? $lineinfo : ">$lineinfo";
7983 # If this is a pipe, the stream points to a slave editor.
7984 $slave_editor = ( $stream =~ /^\|/ );
7986 my $new_lineinfo_fh;
7987 # Open it up and unbuffer it.
7988 open ($new_lineinfo_fh , $stream )
7989 or _db_warn("Cannot open '$stream' for write");
7990 $LINEINFO = $new_lineinfo_fh;
7991 _autoflush($LINEINFO);
7995 } ## end sub LineInfo
7997 =head1 COMMAND SUPPORT ROUTINES
7999 These subroutines provide functionality for various commands.
8001 =head2 C<list_modules>
8003 For the C<M> command: list modules loaded and their versions.
8004 Essentially just runs through the keys in %INC, picks each package's
8005 C<$VERSION> variable, gets the file name, and formats the information
8010 sub list_modules { # versions
8014 # keys are the "as-loaded" name, values are the fully-qualified path
8015 # to the file itself.
8017 $file = $_; # get the module name
8018 s,\.p[lm]$,,i; # remove '.pl' or '.pm'
8019 s,/,::,g; # change '/' to '::'
8020 s/^perl5db$/DB/; # Special case: debugger
8021 # moves to package DB
8022 s/^Term::ReadLine::readline$/readline/; # simplify readline
8024 # If the package has a $VERSION package global (as all good packages
8025 # should!) decode it and save as partial message.
8026 my $pkg_version = do { no strict 'refs'; ${ $_ . '::VERSION' } };
8027 if ( defined $pkg_version ) {
8028 $version{$file} = "$pkg_version from ";
8031 # Finish up the message with the file the package came from.
8032 $version{$file} .= $INC{$file};
8033 } ## end for (keys %INC)
8035 # Hey, dumpit() formats a hash nicely, so why not use it?
8036 dumpit( $OUT, \%version );
8037 } ## end sub list_modules
8041 Sets up the monster string used to format and print the help.
8043 =head3 HELP MESSAGE FORMAT
8045 The help message is a peculiar format unto itself; it mixes C<pod> I<ornaments>
8046 (C<< B<> >> C<< I<> >>) with tabs to come up with a format that's fairly
8047 easy to parse and portable, but which still allows the help to be a little
8048 nicer than just plain text.
8050 Essentially, you define the command name (usually marked up with C<< B<> >>
8051 and C<< I<> >>), followed by a tab, and then the descriptive text, ending in a
8052 newline. The descriptive text can also be marked up in the same way. If you
8053 need to continue the descriptive text to another line, start that line with
8054 just tabs and then enter the marked-up text.
8056 If you are modifying the help text, I<be careful>. The help-string parser is
8057 not very sophisticated, and if you don't follow these rules it will mangle the
8058 help beyond hope until you fix the string.
8062 use vars qw($pre580_help);
8063 use vars qw($pre580_summary);
8067 # XXX: make sure there are tabs between the command and explanation,
8068 # or print_help will screw up your formatting if you have
8069 # eeevil ornaments enabled. This is an insane mess.
8072 Help is currently only available for the new 5.8 command set.
8073 No help is available for the old command set.
8074 We assume you know what you're doing if you switch to it.
8077 B<s> [I<expr>] Single step [in I<expr>].
8078 B<n> [I<expr>] Next, steps over subroutine calls [in I<expr>].
8079 <B<CR>> Repeat last B<n> or B<s> command.
8080 B<r> Return from current subroutine.
8081 B<c> [I<line>|I<sub>] Continue; optionally inserts a one-time-only breakpoint
8082 at the specified position.
8083 B<l> I<min>B<+>I<incr> List I<incr>+1 lines starting at I<min>.
8084 B<l> I<min>B<->I<max> List lines I<min> through I<max>.
8085 B<l> I<line> List single I<line>.
8086 B<l> I<subname> List first window of lines from subroutine.
8087 B<l> I<\$var> List first window of lines from subroutine referenced by I<\$var>.
8088 B<l> List next window of lines.
8089 B<-> List previous window of lines.
8090 B<v> [I<line>] View window around I<line>.
8091 B<.> Return to the executed line.
8092 B<f> I<filename> Switch to viewing I<filename>. File must be already loaded.
8093 I<filename> may be either the full name of the file, or a regular
8094 expression matching the full file name:
8095 B<f> I</home/me/foo.pl> and B<f> I<oo\\.> may access the same file.
8096 Evals (with saved bodies) are considered to be filenames:
8097 B<f> I<(eval 7)> and B<f> I<eval 7\\b> access the body of the 7th eval
8098 (in the order of execution).
8099 B</>I<pattern>B</> Search forwards for I<pattern>; final B</> is optional.
8100 B<?>I<pattern>B<?> Search backwards for I<pattern>; final B<?> is optional.
8101 B<L> [I<a|b|w>] List actions and or breakpoints and or watch-expressions.
8102 B<S> [[B<!>]I<pattern>] List subroutine names [not] matching I<pattern>.
8103 B<t> [I<n>] Toggle trace mode (to max I<n> levels below current stack depth).
8104 B<t> [I<n>] I<expr> Trace through execution of I<expr>.
8105 B<b> Sets breakpoint on current line)
8106 B<b> [I<line>] [I<condition>]
8107 Set breakpoint; I<line> defaults to the current execution line;
8108 I<condition> breaks if it evaluates to true, defaults to '1'.
8109 B<b> I<subname> [I<condition>]
8110 Set breakpoint at first line of subroutine.
8111 B<b> I<\$var> Set breakpoint at first line of subroutine referenced by I<\$var>.
8112 B<b> B<load> I<filename> Set breakpoint on 'require'ing the given file.
8113 B<b> B<postpone> I<subname> [I<condition>]
8114 Set breakpoint at first line of subroutine after
8116 B<b> B<compile> I<subname>
8117 Stop after the subroutine is compiled.
8118 B<B> [I<line>] Delete the breakpoint for I<line>.
8119 B<B> I<*> Delete all breakpoints.
8120 B<a> [I<line>] I<command>
8121 Set an action to be done before the I<line> is executed;
8122 I<line> defaults to the current execution line.
8123 Sequence is: check for breakpoint/watchpoint, print line
8124 if necessary, do action, prompt user if necessary,
8127 B<A> [I<line>] Delete the action for I<line>.
8128 B<A> I<*> Delete all actions.
8129 B<w> I<expr> Add a global watch-expression.
8131 B<W> I<expr> Delete a global watch-expression.
8132 B<W> I<*> Delete all watch-expressions.
8133 B<V> [I<pkg> [I<vars>]] List some (default all) variables in package (default current).
8134 Use B<~>I<pattern> and B<!>I<pattern> for positive and negative regexps.
8135 B<X> [I<vars>] Same as \"B<V> I<currentpackage> [I<vars>]\".
8136 B<x> I<expr> Evals expression in list context, dumps the result.
8137 B<m> I<expr> Evals expression in list context, prints methods callable
8138 on the first element of the result.
8139 B<m> I<class> Prints methods callable via the given class.
8140 B<M> Show versions of loaded modules.
8141 B<i> I<class> Prints nested parents of given class.
8142 B<e> Display current thread id.
8143 B<E> Display all thread ids the current one will be identified: <n>.
8144 B<y> [I<n> [I<Vars>]] List lexicals in higher scope <n>. Vars same as B<V>.
8146 B<<> ? List Perl commands to run before each prompt.
8147 B<<> I<expr> Define Perl command to run before each prompt.
8148 B<<<> I<expr> Add to the list of Perl commands to run before each prompt.
8149 B<< *> Delete the list of perl commands to run before each prompt.
8150 B<>> ? List Perl commands to run after each prompt.
8151 B<>> I<expr> Define Perl command to run after each prompt.
8152 B<>>B<>> I<expr> Add to the list of Perl commands to run after each prompt.
8153 B<>>B< *> Delete the list of Perl commands to run after each prompt.
8154 B<{> I<db_command> Define debugger command to run before each prompt.
8155 B<{> ? List debugger commands to run before each prompt.
8156 B<{{> I<db_command> Add to the list of debugger commands to run before each prompt.
8157 B<{ *> Delete the list of debugger commands to run before each prompt.
8158 B<$prc> I<number> Redo a previous command (default previous command).
8159 B<$prc> I<-number> Redo number'th-to-last command.
8160 B<$prc> I<pattern> Redo last command that started with I<pattern>.
8161 See 'B<O> I<recallCommand>' too.
8162 B<$psh$psh> I<cmd> Run cmd in a subprocess (reads from DB::IN, writes to DB::OUT)"
8167 B<$psh> [I<cmd>] Run I<cmd> in subshell (forces \"\$SHELL -c 'cmd'\")."
8169 See 'B<O> I<shellBang>' too.
8170 B<source> I<file> Execute I<file> containing debugger commands (may nest).
8171 B<save> I<file> Save current debugger session (actual history) to I<file>.
8172 B<rerun> Rerun session to current position.
8173 B<rerun> I<n> Rerun session to numbered command.
8174 B<rerun> I<-n> Rerun session to number'th-to-last command.
8175 B<H> I<-number> Display last number commands (default all).
8176 B<H> I<*> Delete complete history.
8177 B<p> I<expr> Same as \"I<print {DB::OUT} expr>\" in current package.
8178 B<|>I<dbcmd> Run debugger command, piping DB::OUT to current pager.
8179 B<||>I<dbcmd> Same as B<|>I<dbcmd> but DB::OUT is temporarily select()ed as well.
8180 B<\=> [I<alias> I<value>] Define a command alias, or list current aliases.
8181 I<command> Execute as a perl statement in current package.
8182 B<R> Pure-man-restart of debugger, some of debugger state
8183 and command-line options may be lost.
8184 Currently the following settings are preserved:
8185 history, breakpoints and actions, debugger B<O>ptions
8186 and the following command-line options: I<-w>, I<-I>, I<-e>.
8188 B<o> [I<opt>] ... Set boolean option to true
8189 B<o> [I<opt>B<?>] Query options
8190 B<o> [I<opt>B<=>I<val>] [I<opt>=B<\">I<val>B<\">] ...
8191 Set options. Use quotes if spaces in value.
8192 I<recallCommand>, I<ShellBang> chars used to recall command or spawn shell;
8193 I<pager> program for output of \"|cmd\";
8194 I<tkRunning> run Tk while prompting (with ReadLine);
8195 I<signalLevel> I<warnLevel> I<dieLevel> level of verbosity;
8196 I<inhibit_exit> Allows stepping off the end of the script.
8197 I<ImmediateStop> Debugger should stop as early as possible.
8198 I<RemotePort> Remote hostname:port for remote debugging
8199 The following options affect what happens with B<V>, B<X>, and B<x> commands:
8200 I<arrayDepth>, I<hashDepth> print only first N elements ('' for all);
8201 I<compactDump>, I<veryCompact> change style of array and hash dump;
8202 I<globPrint> whether to print contents of globs;
8203 I<DumpDBFiles> dump arrays holding debugged files;
8204 I<DumpPackages> dump symbol tables of packages;
8205 I<DumpReused> dump contents of \"reused\" addresses;
8206 I<quote>, I<HighBit>, I<undefPrint> change style of string dump;
8207 I<bareStringify> Do not print the overload-stringified value;
8208 Other options include:
8209 I<PrintRet> affects printing of return value after B<r> command,
8210 I<frame> affects printing messages on subroutine entry/exit.
8211 I<AutoTrace> affects printing messages on possible breaking points.
8212 I<maxTraceLen> gives max length of evals/args listed in stack trace.
8213 I<ornaments> affects screen appearance of the command line.
8214 I<CreateTTY> bits control attempts to create a new TTY on events:
8215 1: on fork() 2: debugger is started inside debugger
8217 During startup options are initialized from \$ENV{PERLDB_OPTS}.
8218 You can put additional initialization options I<TTY>, I<noTTY>,
8219 I<ReadLine>, I<NonStop>, and I<RemotePort> there (or use
8220 B<R> after you set them).
8222 B<q> or B<^D> Quit. Set B<\$DB::finished = 0> to debug global destruction.
8223 B<h> Summary of debugger commands.
8224 B<h> [I<db_command>] Get help [on a specific debugger command], enter B<|h> to page.
8225 B<h h> Long help for debugger commands
8226 B<$doccmd> I<manpage> Runs the external doc viewer B<$doccmd> command on the
8227 named Perl I<manpage>, or on B<$doccmd> itself if omitted.
8228 Set B<\$DB::doccmd> to change viewer.
8230 Type '|h h' for a paged display if this was too hard to read.
8232 "; # Fix balance of vi % matching: }}}}
8234 # note: tabs in the following section are not-so-helpful
8235 $summary = <<"END_SUM";
8236 I<List/search source lines:> I<Control script execution:>
8237 B<l> [I<ln>|I<sub>] List source code B<T> Stack trace
8238 B<-> or B<.> List previous/current line B<s> [I<expr>] Single step [in expr]
8239 B<v> [I<line>] View around line B<n> [I<expr>] Next, steps over subs
8240 B<f> I<filename> View source in file <B<CR>/B<Enter>> Repeat last B<n> or B<s>
8241 B</>I<pattern>B</> B<?>I<patt>B<?> Search forw/backw B<r> Return from subroutine
8242 B<M> Show module versions B<c> [I<ln>|I<sub>] Continue until position
8243 I<Debugger controls:> B<L> List break/watch/actions
8244 B<o> [...] Set debugger options B<t> [I<n>] [I<expr>] Toggle trace [max depth] ][trace expr]
8245 B<<>[B<<>]|B<{>[B<{>]|B<>>[B<>>] [I<cmd>] Do pre/post-prompt B<b> [I<ln>|I<event>|I<sub>] [I<cnd>] Set breakpoint
8246 B<$prc> [I<N>|I<pat>] Redo a previous command B<B> I<ln|*> Delete a/all breakpoints
8247 B<H> [I<-num>] Display last num commands B<a> [I<ln>] I<cmd> Do cmd before line
8248 B<=> [I<a> I<val>] Define/list an alias B<A> I<ln|*> Delete a/all actions
8249 B<h> [I<db_cmd>] Get help on command B<w> I<expr> Add a watch expression
8250 B<h h> Complete help page B<W> I<expr|*> Delete a/all watch exprs
8251 B<|>[B<|>]I<db_cmd> Send output to pager B<$psh>\[B<$psh>\] I<syscmd> Run cmd in a subprocess
8252 B<q> or B<^D> Quit B<R> Attempt a restart
8253 I<Data Examination:> B<expr> Execute perl code, also see: B<s>,B<n>,B<t> I<expr>
8254 B<x>|B<m> I<expr> Evals expr in list context, dumps the result or lists methods.
8255 B<p> I<expr> Print expression (uses script's current package).
8256 B<S> [[B<!>]I<pat>] List subroutine names [not] matching pattern
8257 B<V> [I<Pk> [I<Vars>]] List Variables in Package. Vars can be ~pattern or !pattern.
8258 B<X> [I<Vars>] Same as \"B<V> I<current_package> [I<Vars>]\". B<i> I<class> inheritance tree.
8259 B<y> [I<n> [I<Vars>]] List lexicals in higher scope <n>. Vars same as B<V>.
8260 B<e> Display thread id B<E> Display all thread ids.
8261 For more help, type B<h> I<cmd_letter>, or run B<$doccmd perldebug> for all docs.
8264 # ')}}; # Fix balance of vi % matching
8266 # and this is really numb...
8269 B<s> [I<expr>] Single step [in I<expr>].
8270 B<n> [I<expr>] Next, steps over subroutine calls [in I<expr>].
8271 B<CR>> Repeat last B<n> or B<s> command.
8272 B<r> Return from current subroutine.
8273 B<c> [I<line>|I<sub>] Continue; optionally inserts a one-time-only breakpoint
8274 at the specified position.
8275 B<l> I<min>B<+>I<incr> List I<incr>+1 lines starting at I<min>.
8276 B<l> I<min>B<->I<max> List lines I<min> through I<max>.
8277 B<l> I<line> List single I<line>.
8278 B<l> I<subname> List first window of lines from subroutine.
8279 B<l> I<\$var> List first window of lines from subroutine referenced by I<\$var>.
8280 B<l> List next window of lines.
8281 B<-> List previous window of lines.
8282 B<w> [I<line>] List window around I<line>.
8283 B<.> Return to the executed line.
8284 B<f> I<filename> Switch to viewing I<filename>. File must be already loaded.
8285 I<filename> may be either the full name of the file, or a regular
8286 expression matching the full file name:
8287 B<f> I</home/me/foo.pl> and B<f> I<oo\\.> may access the same file.
8288 Evals (with saved bodies) are considered to be filenames:
8289 B<f> I<(eval 7)> and B<f> I<eval 7\\b> access the body of the 7th eval
8290 (in the order of execution).
8291 B</>I<pattern>B</> Search forwards for I<pattern>; final B</> is optional.
8292 B<?>I<pattern>B<?> Search backwards for I<pattern>; final B<?> is optional.
8293 B<L> List all breakpoints and actions.
8294 B<S> [[B<!>]I<pattern>] List subroutine names [not] matching I<pattern>.
8295 B<t> [I<n>] Toggle trace mode (to max I<n> levels below current stack depth) .
8296 B<t> [I<n>] I<expr> Trace through execution of I<expr>.
8297 B<b> [I<line>] [I<condition>]
8298 Set breakpoint; I<line> defaults to the current execution line;
8299 I<condition> breaks if it evaluates to true, defaults to '1'.
8300 B<b> I<subname> [I<condition>]
8301 Set breakpoint at first line of subroutine.
8302 B<b> I<\$var> Set breakpoint at first line of subroutine referenced by I<\$var>.
8303 B<b> B<load> I<filename> Set breakpoint on 'require'ing the given file.
8304 B<b> B<postpone> I<subname> [I<condition>]
8305 Set breakpoint at first line of subroutine after
8307 B<b> B<compile> I<subname>
8308 Stop after the subroutine is compiled.
8309 B<d> [I<line>] Delete the breakpoint for I<line>.
8310 B<D> Delete all breakpoints.
8311 B<a> [I<line>] I<command>
8312 Set an action to be done before the I<line> is executed;
8313 I<line> defaults to the current execution line.
8314 Sequence is: check for breakpoint/watchpoint, print line
8315 if necessary, do action, prompt user if necessary,
8317 B<a> [I<line>] Delete the action for I<line>.
8318 B<A> Delete all actions.
8319 B<W> I<expr> Add a global watch-expression.
8320 B<W> Delete all watch-expressions.
8321 B<V> [I<pkg> [I<vars>]] List some (default all) variables in package (default current).
8322 Use B<~>I<pattern> and B<!>I<pattern> for positive and negative regexps.
8323 B<X> [I<vars>] Same as \"B<V> I<currentpackage> [I<vars>]\".
8324 B<x> I<expr> Evals expression in list context, dumps the result.
8325 B<m> I<expr> Evals expression in list context, prints methods callable
8326 on the first element of the result.
8327 B<m> I<class> Prints methods callable via the given class.
8329 B<<> ? List Perl commands to run before each prompt.
8330 B<<> I<expr> Define Perl command to run before each prompt.
8331 B<<<> I<expr> Add to the list of Perl commands to run before each prompt.
8332 B<>> ? List Perl commands to run after each prompt.
8333 B<>> I<expr> Define Perl command to run after each prompt.
8334 B<>>B<>> I<expr> Add to the list of Perl commands to run after each prompt.
8335 B<{> I<db_command> Define debugger command to run before each prompt.
8336 B<{> ? List debugger commands to run before each prompt.
8337 B<{{> I<db_command> Add to the list of debugger commands to run before each prompt.
8338 B<$prc> I<number> Redo a previous command (default previous command).
8339 B<$prc> I<-number> Redo number'th-to-last command.
8340 B<$prc> I<pattern> Redo last command that started with I<pattern>.
8341 See 'B<O> I<recallCommand>' too.
8342 B<$psh$psh> I<cmd> Run cmd in a subprocess (reads from DB::IN, writes to DB::OUT)"
8347 B<$psh> [I<cmd>] Run I<cmd> in subshell (forces \"\$SHELL -c 'cmd'\")."
8349 See 'B<O> I<shellBang>' too.
8350 B<source> I<file> Execute I<file> containing debugger commands (may nest).
8351 B<H> I<-number> Display last number commands (default all).
8352 B<p> I<expr> Same as \"I<print {DB::OUT} expr>\" in current package.
8353 B<|>I<dbcmd> Run debugger command, piping DB::OUT to current pager.
8354 B<||>I<dbcmd> Same as B<|>I<dbcmd> but DB::OUT is temporarilly select()ed as well.
8355 B<\=> [I<alias> I<value>] Define a command alias, or list current aliases.
8356 I<command> Execute as a perl statement in current package.
8357 B<v> Show versions of loaded modules.
8358 B<R> Pure-man-restart of debugger, some of debugger state
8359 and command-line options may be lost.
8360 Currently the following settings are preserved:
8361 history, breakpoints and actions, debugger B<O>ptions
8362 and the following command-line options: I<-w>, I<-I>, I<-e>.
8364 B<O> [I<opt>] ... Set boolean option to true
8365 B<O> [I<opt>B<?>] Query options
8366 B<O> [I<opt>B<=>I<val>] [I<opt>=B<\">I<val>B<\">] ...
8367 Set options. Use quotes if spaces in value.
8368 I<recallCommand>, I<ShellBang> chars used to recall command or spawn shell;
8369 I<pager> program for output of \"|cmd\";
8370 I<tkRunning> run Tk while prompting (with ReadLine);
8371 I<signalLevel> I<warnLevel> I<dieLevel> level of verbosity;
8372 I<inhibit_exit> Allows stepping off the end of the script.
8373 I<ImmediateStop> Debugger should stop as early as possible.
8374 I<RemotePort> Remote hostname:port for remote debugging
8375 The following options affect what happens with B<V>, B<X>, and B<x> commands:
8376 I<arrayDepth>, I<hashDepth> print only first N elements ('' for all);
8377 I<compactDump>, I<veryCompact> change style of array and hash dump;
8378 I<globPrint> whether to print contents of globs;
8379 I<DumpDBFiles> dump arrays holding debugged files;
8380 I<DumpPackages> dump symbol tables of packages;
8381 I<DumpReused> dump contents of \"reused\" addresses;
8382 I<quote>, I<HighBit>, I<undefPrint> change style of string dump;
8383 I<bareStringify> Do not print the overload-stringified value;
8384 Other options include:
8385 I<PrintRet> affects printing of return value after B<r> command,
8386 I<frame> affects printing messages on subroutine entry/exit.
8387 I<AutoTrace> affects printing messages on possible breaking points.
8388 I<maxTraceLen> gives max length of evals/args listed in stack trace.
8389 I<ornaments> affects screen appearance of the command line.
8390 I<CreateTTY> bits control attempts to create a new TTY on events:
8391 1: on fork() 2: debugger is started inside debugger
8393 During startup options are initialized from \$ENV{PERLDB_OPTS}.
8394 You can put additional initialization options I<TTY>, I<noTTY>,
8395 I<ReadLine>, I<NonStop>, and I<RemotePort> there (or use
8396 B<R> after you set them).
8398 B<q> or B<^D> Quit. Set B<\$DB::finished = 0> to debug global destruction.
8399 B<h> [I<db_command>] Get help [on a specific debugger command], enter B<|h> to page.
8400 B<h h> Summary of debugger commands.
8401 B<$doccmd> I<manpage> Runs the external doc viewer B<$doccmd> command on the
8402 named Perl I<manpage>, or on B<$doccmd> itself if omitted.
8403 Set B<\$DB::doccmd> to change viewer.
8405 Type '|h' for a paged display if this was too hard to read.
8407 "; # Fix balance of vi % matching: }}}}
8409 # note: tabs in the following section are not-so-helpful
8410 $pre580_summary = <<"END_SUM";
8411 I<List/search source lines:> I<Control script execution:>
8412 B<l> [I<ln>|I<sub>] List source code B<T> Stack trace
8413 B<-> or B<.> List previous/current line B<s> [I<expr>] Single step [in expr]
8414 B<w> [I<line>] List around line B<n> [I<expr>] Next, steps over subs
8415 B<f> I<filename> View source in file <B<CR>/B<Enter>> Repeat last B<n> or B<s>
8416 B</>I<pattern>B</> B<?>I<patt>B<?> Search forw/backw B<r> Return from subroutine
8417 B<v> Show versions of modules B<c> [I<ln>|I<sub>] Continue until position
8418 I<Debugger controls:> B<L> List break/watch/actions
8419 B<O> [...] Set debugger options B<t> [I<expr>] Toggle trace [trace expr]
8420 B<<>[B<<>]|B<{>[B<{>]|B<>>[B<>>] [I<cmd>] Do pre/post-prompt B<b> [I<ln>|I<event>|I<sub>] [I<cnd>] Set breakpoint
8421 B<$prc> [I<N>|I<pat>] Redo a previous command B<d> [I<ln>] or B<D> Delete a/all breakpoints
8422 B<H> [I<-num>] Display last num commands B<a> [I<ln>] I<cmd> Do cmd before line
8423 B<=> [I<a> I<val>] Define/list an alias B<W> I<expr> Add a watch expression
8424 B<h> [I<db_cmd>] Get help on command B<A> or B<W> Delete all actions/watch
8425 B<|>[B<|>]I<db_cmd> Send output to pager B<$psh>\[B<$psh>\] I<syscmd> Run cmd in a subprocess
8426 B<q> or B<^D> Quit B<R> Attempt a restart
8427 I<Data Examination:> B<expr> Execute perl code, also see: B<s>,B<n>,B<t> I<expr>
8428 B<x>|B<m> I<expr> Evals expr in list context, dumps the result or lists methods.
8429 B<p> I<expr> Print expression (uses script's current package).
8430 B<S> [[B<!>]I<pat>] List subroutine names [not] matching pattern
8431 B<V> [I<Pk> [I<Vars>]] List Variables in Package. Vars can be ~pattern or !pattern.
8432 B<X> [I<Vars>] Same as \"B<V> I<current_package> [I<Vars>]\".
8433 B<y> [I<n> [I<Vars>]] List lexicals in higher scope <n>. Vars same as B<V>.
8434 For more help, type B<h> I<cmd_letter>, or run B<$doccmd perldebug> for all docs.
8437 # ')}}; # Fix balance of vi % matching
8439 } ## end sub sethelp
8441 =head2 C<print_help()>
8443 Most of what C<print_help> does is just text formatting. It finds the
8444 C<B> and C<I> ornaments, cleans them off, and substitutes the proper
8445 terminal control characters to simulate them (courtesy of
8446 C<Term::ReadLine::TermCap>).
8451 my $help_str = shift;
8453 # Restore proper alignment destroyed by eeevil I<> and B<>
8454 # ornaments: A pox on both their houses!
8456 # A help command will have everything up to and including
8457 # the first tab sequence padded into a field 16 (or if indented 20)
8458 # wide. If it's wider than that, an extra space will be added.
8460 ^ # only matters at start of line
8461 ( \ {4} | \t )* # some subcommands are indented
8462 ( < ? # so <CR> works
8463 [BI] < [^\t\n] + ) # find an eeevil ornament
8464 ( \t+ ) # original separation, discarded
8465 ( .* ) # this will now start (no earlier) than
8468 my($leadwhite, $command, $midwhite, $text) = ($1, $2, $3, $4);
8469 my $clean = $command;
8470 $clean =~ s/[BI]<([^>]*)>/$1/g;
8472 # replace with this whole string:
8473 ($leadwhite ? " " x 4 : "")
8475 . ((" " x (16 + ($leadwhite ? 4 : 0) - length($clean))) || " ")
8480 $help_str =~ s{ # handle bold ornaments
8481 B < ( [^>] + | > ) >
8483 $Term::ReadLine::TermCap::rl_term_set[2]
8485 . $Term::ReadLine::TermCap::rl_term_set[3]
8488 $help_str =~ s{ # handle italic ornaments
8489 I < ( [^>] + | > ) >
8491 $Term::ReadLine::TermCap::rl_term_set[0]
8493 . $Term::ReadLine::TermCap::rl_term_set[1]
8497 print {$OUT} $help_str;
8500 } ## end sub print_help
8504 This routine does a lot of gyrations to be sure that the pager is C<less>.
8505 It checks for C<less> masquerading as C<more> and records the result in
8506 C<$fixed_less> so we don't have to go through doing the stats again.
8510 use vars qw($fixed_less);
8513 if ($pager =~ /\bless\b/)
8517 elsif ($pager =~ /\bmore\b/)
8519 # Nope, set to more. See what's out there.
8520 my @st_more = stat('/usr/bin/more');
8521 my @st_less = stat('/usr/bin/less');
8523 # is it really less, pretending to be more?
8527 && $st_more[0] == $st_less[0]
8528 && $st_more[1] == $st_less[1]
8538 # We already know if this is set.
8539 return if $fixed_less;
8541 # changes environment!
8542 # 'r' added so we don't do (slow) stats again.
8543 $fixed_less = 1 if _calc_is_less();
8546 } ## end sub fix_less
8548 =head1 DIE AND WARN MANAGEMENT
8552 C<diesignal> is a just-drop-dead C<die> handler. It's most useful when trying
8553 to debug a debugger problem.
8555 It does its best to report the error that occurred, and then forces the
8556 program, debugger, and everything to die.
8562 # No entry/exit messages.
8565 # No return value prints.
8568 # set the abort signal handling to the default (just terminate).
8569 $SIG{'ABRT'} = 'DEFAULT';
8571 # If we enter the signal handler recursively, kill myself with an
8572 # abort signal (so we just terminate).
8573 kill 'ABRT', $$ if $panic++;
8575 # If we can show detailed info, do so.
8576 if ( defined &Carp::longmess ) {
8578 # Don't recursively enter the warn handler, since we're carping.
8579 local $SIG{__WARN__} = '';
8581 # Skip two levels before reporting traceback: we're skipping
8582 # mydie and confess.
8583 local $Carp::CarpLevel = 2; # mydie + confess
8585 # Tell us all about it.
8586 _db_warn( Carp::longmess("Signal @_") );
8589 # No Carp. Tell us about the signal as best we can.
8592 print $DB::OUT "Got signal @_\n";
8597 } ## end sub diesignal
8601 The debugger's own default C<$SIG{__WARN__}> handler. We load C<Carp> to
8602 be able to get a stack trace, and output the warning message vi C<DB::dbwarn()>.
8608 # No entry/exit trace.
8611 # No return value printing.
8614 # Turn off warn and die handling to prevent recursive entries to this
8616 local $SIG{__WARN__} = '';
8617 local $SIG{__DIE__} = '';
8619 # Load Carp if we can. If $^S is false (current thing being compiled isn't
8620 # done yet), we may not be able to do a require.
8621 eval { require Carp }
8622 if defined $^S; # If error/warning during compilation,
8623 # require may be broken.
8625 # Use the core warn() unless Carp loaded OK.
8627 "\nCannot print stack trace, load with -MCarp option to see stack" ),
8629 unless defined &Carp::longmess;
8631 # Save the current values of $single and $trace, and then turn them off.
8632 my ( $mysingle, $mytrace ) = ( $single, $trace );
8636 # We can call Carp::longmess without its being "debugged" (which we
8637 # don't want - we just want to use it!). Capture this for later.
8638 my $mess = Carp::longmess(@_);
8640 # Restore $single and $trace to their original values.
8641 ( $single, $trace ) = ( $mysingle, $mytrace );
8643 # Use the debugger's own special way of printing warnings to print
8644 # the stack trace message.
8650 The debugger's own C<$SIG{__DIE__}> handler. Handles providing a stack trace
8651 by loading C<Carp> and calling C<Carp::longmess()> to get it. We turn off
8652 single stepping and tracing during the call to C<Carp::longmess> to avoid
8653 debugging it - we just want to use it.
8655 If C<dieLevel> is zero, we let the program being debugged handle the
8656 exceptions. If it's 1, you get backtraces for any exception. If it's 2,
8657 the debugger takes over all exception handling, printing a backtrace and
8658 displaying the exception via its C<dbwarn()> routine.
8665 local $SIG{__DIE__} = '';
8666 local $SIG{__WARN__} = '';
8667 if ( $dieLevel > 2 ) {
8668 local $SIG{__WARN__} = \&dbwarn;
8669 _db_warn(@_); # Yell no matter what
8672 if ( $dieLevel < 2 ) {
8673 die @_ if $^S; # in eval propagate
8676 # The code used to check $^S to see if compilation of the current thing
8677 # hadn't finished. We don't do it anymore, figuring eval is pretty stable.
8678 eval { require Carp };
8681 "\nCannot print stack trace, load with -MCarp option to see stack" )
8682 unless defined &Carp::longmess;
8684 # We do not want to debug this chunk (automatic disabling works
8685 # inside DB::DB, but not in Carp). Save $single and $trace, turn them off,
8686 # get the stack trace from Carp::longmess (if possible), restore $signal
8687 # and $trace, and then die with the stack trace.
8688 my ( $mysingle, $mytrace ) = ( $single, $trace );
8694 package Carp; # Do not include us in the list
8695 eval { $mess = Carp::longmess(@_); };
8697 ( $single, $trace ) = ( $mysingle, $mytrace );
8701 =head2 C<warnlevel()>
8703 Set the C<$DB::warnLevel> variable that stores the value of the
8704 C<warnLevel> option. Calling C<warnLevel()> with a positive value
8705 results in the debugger taking over all warning handlers. Setting
8706 C<warnLevel> to zero leaves any warning handlers set up by the program
8707 being debugged in place.
8713 my $prevwarn = $SIG{__WARN__} unless $warnLevel;
8716 $SIG{__WARN__} = \&DB::dbwarn;
8719 $SIG{__WARN__} = $prevwarn;
8721 undef $SIG{__WARN__};
8725 } ## end sub warnLevel
8729 Similar to C<warnLevel>. Non-zero values for C<dieLevel> result in the
8730 C<DB::dbdie()> function overriding any other C<die()> handler. Setting it to
8731 zero lets you use your own C<die()> handler.
8738 my $prevdie = $SIG{__DIE__} unless $dieLevel;
8742 # Always set it to dbdie() for non-zero values.
8743 $SIG{__DIE__} = \&DB::dbdie; # if $dieLevel < 2;
8745 # No longer exists, so don't try to use it.
8746 #$SIG{__DIE__} = \&DB::diehard if $dieLevel >= 2;
8748 # If we've finished initialization, mention that stack dumps
8749 # are enabled, If dieLevel is 1, we won't stack dump if we die
8751 print $OUT "Stack dump during die enabled",
8752 ( $dieLevel == 1 ? " outside of evals" : "" ), ".\n"
8755 # XXX This is probably obsolete, given that diehard() is gone.
8756 print $OUT "Dump printed too.\n" if $dieLevel > 2;
8757 } ## end if ($dieLevel)
8759 # Put the old one back if there was one.
8761 $SIG{__DIE__} = $prevdie;
8762 print $OUT "Default die handler restored.\n";
8764 undef $SIG{__DIE__};
8765 print $OUT "Die handler removed.\n";
8769 } ## end sub dieLevel
8771 =head2 C<signalLevel>
8773 Number three in a series: set C<signalLevel> to zero to keep your own
8774 signal handler for C<SIGSEGV> and/or C<SIGBUS>. Otherwise, the debugger
8775 takes over and handles them with C<DB::diesignal()>.
8781 my $prevsegv = $SIG{SEGV} unless $signalLevel;
8782 my $prevbus = $SIG{BUS} unless $signalLevel;
8783 $signalLevel = shift;
8785 $SIG{SEGV} = \&DB::diesignal;
8786 $SIG{BUS} = \&DB::diesignal;
8789 $SIG{SEGV} = $prevsegv;
8790 $SIG{BUS} = $prevbus;
8794 } ## end sub signalLevel
8796 =head1 SUBROUTINE DECODING SUPPORT
8798 These subroutines are used during the C<x> and C<X> commands to try to
8799 produce as much information as possible about a code reference. They use
8800 L<Devel::Peek> to try to find the glob in which this code reference lives
8801 (if it does) - this allows us to actually code references which correspond
8802 to named subroutines (including those aliased via glob assignment).
8804 =head2 C<CvGV_name()>
8806 Wrapper for C<CvGV_name_or_bust>; tries to get the name of a reference
8807 via that routine. If this fails, return the reference again (when the
8808 reference is stringified, it'll come out as C<SOMETHING(0x...)>).
8814 my $name = CvGV_name_or_bust($in);
8815 defined $name ? $name : $in;
8818 =head2 C<CvGV_name_or_bust> I<coderef>
8820 Calls L<Devel::Peek> to try to find the glob the ref lives in; returns
8821 C<undef> if L<Devel::Peek> can't be loaded, or if C<Devel::Peek::CvGV> can't
8822 find a glob for this ref.
8824 Returns C<< I<package>::I<glob name> >> if the code ref is found in a glob.
8828 use vars qw($skipCvGV);
8830 sub CvGV_name_or_bust {
8832 return if $skipCvGV; # Backdoor to avoid problems if XS broken...
8833 return unless ref $in;
8834 $in = \&$in; # Hard reference...
8835 eval { require Devel::Peek; 1 } or return;
8836 my $gv = Devel::Peek::CvGV($in) or return;
8837 *$gv{PACKAGE} . '::' . *$gv{NAME};
8838 } ## end sub CvGV_name_or_bust
8842 A utility routine used in various places; finds the file where a subroutine
8843 was defined, and returns that filename and a line-number range.
8845 Tries to use C<@sub> first; if it can't find it there, it tries building a
8846 reference to the subroutine and uses C<CvGV_name_or_bust> to locate it,
8847 loading it into C<@sub> as a side effect (XXX I think). If it can't find it
8848 this way, it brute-force searches C<%sub>, checking for identical references.
8852 sub _find_sub_helper {
8855 return unless defined &$subr;
8856 my $name = CvGV_name_or_bust($subr);
8858 $data = $sub{$name} if defined $name;
8859 return $data if defined $data;
8862 $subr = \&$subr; # Hard reference
8865 $s = $_, last if $subr eq \&$_;
8880 return ( $sub{$subr} || _find_sub_helper($subr) );
8881 } ## end sub find_sub
8885 A subroutine that uses the utility function C<methods_via> to find all the
8886 methods in the class corresponding to the current reference and in
8895 # Figure out the class - either this is the class or it's a reference
8896 # to something blessed into that class.
8898 $class = ref $class if ref $class;
8902 # Show the methods that this class has.
8903 methods_via( $class, '', 1 );
8905 # Show the methods that UNIVERSAL has.
8906 methods_via( 'UNIVERSAL', 'UNIVERSAL', 0 );
8907 } ## end sub methods
8909 =head2 C<methods_via($class, $prefix, $crawl_upward)>
8911 C<methods_via> does the work of crawling up the C<@ISA> tree and reporting
8912 all the parent class methods. C<$class> is the name of the next class to
8913 try; C<$prefix> is the message prefix, which gets built up as we go up the
8914 C<@ISA> tree to show parentage; C<$crawl_upward> is 1 if we should try to go
8915 higher in the C<@ISA> tree, 0 if we should stop.
8921 # If we've processed this class already, just quit.
8923 return if $seen{$class}++;
8925 # This is a package that is contributing the methods we're about to print.
8927 my $prepend = $prefix ? "via $prefix: " : '';
8930 # Extract from all the symbols in this class.
8931 my $class_ref = do { no strict "refs"; \%{$class . '::'} };
8932 while (my ($name, $glob) = each %$class_ref) {
8933 # references directly in the symbol table are Proxy Constant
8934 # Subroutines, and are by their very nature defined
8935 # Otherwise, check if the thing is a typeglob, and if it is, it decays
8936 # to a subroutine reference, which can be tested by defined.
8937 # $glob might also be the value -1 (from sub foo;)
8938 # or (say) '$$' (from sub foo ($$);)
8939 # \$glob will be SCALAR in both cases.
8940 if ((ref $glob || ($glob && ref \$glob eq 'GLOB' && defined &$glob))
8941 && !$seen{$name}++) {
8942 push @to_print, "$prepend$name\n";
8949 print $DB::OUT $_ foreach sort @to_print;
8952 # If the $crawl_upward argument is false, just quit here.
8953 return unless shift;
8955 # $crawl_upward true: keep going up the tree.
8956 # Find all the classes this one is a subclass of.
8957 my $class_ISA_ref = do { no strict "refs"; \@{"${class}::ISA"} };
8958 for my $name ( @$class_ISA_ref ) {
8960 # Set up the new prefix.
8961 $prepend = $prefix ? $prefix . " -> $name" : $name;
8963 # Crawl up the tree and keep trying to crawl up.
8964 methods_via( $name, $prepend, 1 );
8966 } ## end sub methods_via
8968 =head2 C<setman> - figure out which command to use to show documentation
8970 Just checks the contents of C<$^O> and sets the C<$doccmd> global accordingly.
8975 $doccmd = $^O !~ /^(?:MSWin32|VMS|os2|dos|amigaos|riscos|NetWare)\z/s
8976 ? "man" # O Happy Day!
8977 : "perldoc"; # Alas, poor unfortunates
8980 =head2 C<runman> - run the appropriate command to show documentation
8982 Accepts a man page name; runs the appropriate command to display it (set up
8983 during debugger initialization). Uses C<_db_system()> to avoid mucking up the
8984 program's STDIN and STDOUT.
8991 _db_system("$doccmd $doccmd");
8995 # this way user can override, like with $doccmd="man -Mwhatever"
8996 # or even just "man " to disable the path check.
8997 if ( $doccmd ne 'man' ) {
8998 _db_system("$doccmd $page");
9002 $page = 'perl' if lc($page) eq 'help';
9005 my $man1dir = $Config::Config{man1direxp};
9006 my $man3dir = $Config::Config{man3direxp};
9007 for ( $man1dir, $man3dir ) { s#/[^/]*\z## if /\S/ }
9009 $manpath .= "$man1dir:" if $man1dir =~ /\S/;
9010 $manpath .= "$man3dir:" if $man3dir =~ /\S/ && $man1dir ne $man3dir;
9011 chop $manpath if $manpath;
9013 # harmless if missing, I figure
9014 local $ENV{MANPATH} = $manpath if $manpath;
9015 my $nopathopt = $^O =~ /dunno what goes here/;
9020 # I just *know* there are men without -M
9021 ( ( $manpath && !$nopathopt ) ? ( "-M", $manpath ) : () ),
9026 unless ( $page =~ /^perl\w/ ) {
9027 # Previously the debugger contained a list which it slurped in,
9028 # listing the known "perl" manpages. However, it was out of date,
9029 # with errors both of omission and inclusion. This approach is
9030 # considerably less complex. The failure mode on a butchered
9031 # install is simply that the user has to run man or perldoc
9032 # "manually" with the full manpage name.
9034 # There is a list of $^O values in installperl to determine whether
9035 # the directory is 'pods' or 'pod'. However, we can avoid tight
9036 # coupling to that by simply checking the "non-standard" 'pods'
9038 my $pods = "$Config::Config{privlibexp}/pods";
9039 $pods = "$Config::Config{privlibexp}/pod"
9041 if (-f "$pods/perl$page.pod") {
9042 CORE::system( $doccmd,
9043 ( ( $manpath && !$nopathopt ) ? ( "-M", $manpath ) : () ),
9047 } ## end if (CORE::system($doccmd...
9050 #use Carp; # This did break, left for debugging
9052 =head1 DEBUGGER INITIALIZATION - THE SECOND BEGIN BLOCK
9054 Because of the way the debugger interface to the Perl core is designed, any
9055 debugger package globals that C<DB::sub()> requires have to be defined before
9056 any subroutines can be called. These are defined in the second C<BEGIN> block.
9058 This block sets things up so that (basically) the world is sane
9059 before the debugger starts executing. We set up various variables that the
9060 debugger has to have set up before the Perl core starts running:
9066 The debugger's own filehandles (copies of STD and STDOUT for now).
9070 Characters for shell escapes, the recall command, and the history command.
9074 The maximum recursion depth.
9078 The size of a C<w> command's window.
9082 The before-this-line context to be printed in a C<v> (view a window around this line) command.
9086 The fact that we're not in a sub at all right now.
9090 The default SIGINT handler for the debugger.
9094 The appropriate value of the flag in C<$^D> that says the debugger is running
9098 The current debugger recursion level
9102 The list of postponed items and the C<$single> stack (XXX define this)
9106 That we want no return values and no subroutine entry/exit trace.
9112 # The following BEGIN is very handy if debugger goes havoc, debugging debugger?
9114 use vars qw($db_stop);
9116 BEGIN { # This does not compile, alas. (XXX eh?)
9117 $IN = \*STDIN; # For bugs before DB::OUT has been opened
9118 $OUT = \*STDERR; # For errors before DB::OUT has been opened
9120 # Define characters used by command parsing.
9121 $sh = '!'; # Shell escape (does not work)
9122 $rc = ','; # Recall command (does not work)
9123 @hist = ('?'); # Show history (does not work)
9124 @truehist = (); # Can be saved for replay (per session)
9126 # This defines the point at which you get the 'deep recursion'
9127 # warning. It MUST be defined or the debugger will not load.
9130 # Number of lines around the current one that are shown in the
9134 # How much before-the-current-line context the 'v' command should
9135 # use in calculating the start of the window it will display.
9138 # We're not in any sub yet, but we need this to be a defined value.
9141 # Set up the debugger's interrupt handler. It simply sets a flag
9142 # ($signal) that DB::DB() will check before each command is executed.
9143 $SIG{INT} = \&DB::catch;
9145 # The following lines supposedly, if uncommented, allow the debugger to
9146 # debug itself. Perhaps we can try that someday.
9147 # This may be enabled to debug debugger:
9148 #$warnLevel = 1 unless defined $warnLevel;
9149 #$dieLevel = 1 unless defined $dieLevel;
9150 #$signalLevel = 1 unless defined $signalLevel;
9152 # This is the flag that says "a debugger is running, please call
9153 # DB::DB and DB::sub". We will turn it on forcibly before we try to
9154 # execute anything in the user's context, because we always want to
9156 $db_stop = 0; # Compiler warning ...
9157 $db_stop = 1 << 30; # ... because this is only used in an eval() later.
9159 # This variable records how many levels we're nested in debugging. Used
9160 # Used in the debugger prompt, and in determining whether it's all over or
9162 $level = 0; # Level of recursive debugging
9164 # "Triggers bug (?) in perl if we postpone this until runtime."
9165 # XXX No details on this yet, or whether we should fix the bug instead
9166 # of work around it. Stay tuned.
9169 # Used to track the current stack depth using the auto-stacked-variable
9171 $stack_depth = 0; # Localized repeatedly; simple way to track $#stack
9173 # Don't print return values on exiting a subroutine.
9176 # No extry/exit tracing.
9181 BEGIN { $^W = $ini_warn; } # Switch warnings back
9183 =head1 READLINE SUPPORT - COMPLETION FUNCTION
9187 C<readline> support - adds command completion to basic C<readline>.
9189 Returns a list of possible completions to C<readline> when invoked. C<readline>
9190 will print the longest common substring following the text already entered.
9192 If there is only a single possible completion, C<readline> will use it in full.
9194 This code uses C<map> and C<grep> heavily to create lists of possible
9195 completion. Think LISP in this section.
9201 # Specific code for b c l V m f O, &blah, $blah, @blah, %blah
9202 # $text is the text to be completed.
9203 # $line is the incoming line typed by the user.
9204 # $start is the start of the text to be completed in the incoming line.
9205 my ( $text, $line, $start ) = @_;
9207 # Save the initial text.
9208 # The search pattern is current package, ::, extract the next qualifier
9209 # Prefix and pack are set to undef.
9210 my ( $itext, $search, $prefix, $pack ) =
9211 ( $text, "^\Q${package}::\E([^:]+)\$" );
9213 =head3 C<b postpone|compile>
9219 Find all the subroutines that might match in this package
9223 Add C<postpone>, C<load>, and C<compile> as possibles (we may be completing the keyword itself)
9227 Include all the rest of the subs that are known
9231 C<grep> out the ones that match the text we have so far
9235 Return this as the list of possible completions
9241 return sort grep /^\Q$text/, ( keys %sub ),
9242 qw(postpone load compile), # subroutines
9243 ( map { /$search/ ? ($1) : () } keys %sub )
9244 if ( substr $line, 0, $start ) =~ /^\|*[blc]\s+((postpone|compile)\s+)?$/;
9248 Get all the possible files from C<@INC> as it currently stands and
9249 select the ones that match the text so far.
9253 return sort grep /^\Q$text/, values %INC # files
9254 if ( substr $line, 0, $start ) =~ /^\|*b\s+load\s+$/;
9256 =head3 C<V> (list variable) and C<m> (list modules)
9258 There are two entry points for these commands:
9260 =head4 Unqualified package names
9262 Get the top-level packages and grab everything that matches the text
9263 so far. For each match, recursively complete the partial packages to
9264 get all possible matching packages. Return this sorted list.
9268 return sort map { ( $_, db_complete( $_ . "::", "V ", 2 ) ) }
9269 grep /^\Q$text/, map { /^(.*)::$/ ? ($1) : () } keys %:: # top-packages
9270 if ( substr $line, 0, $start ) =~ /^\|*[Vm]\s+$/ and $text =~ /^\w*$/;
9272 =head4 Qualified package names
9274 Take a partially-qualified package and find all subpackages for it
9275 by getting all the subpackages for the package so far, matching all
9276 the subpackages against the text, and discarding all of them which
9277 start with 'main::'. Return this list.
9281 return sort map { ( $_, db_complete( $_ . "::", "V ", 2 ) ) }
9282 grep !/^main::/, grep /^\Q$text/,
9283 map { /^(.*)::$/ ? ( $prefix . "::$1" ) : () }
9284 do { no strict 'refs'; keys %{ $prefix . '::' } }
9285 if ( substr $line, 0, $start ) =~ /^\|*[Vm]\s+$/
9286 and $text =~ /^(.*[^:])::?(\w*)$/
9289 =head3 C<f> - switch files
9291 Here, we want to get a fully-qualified filename for the C<f> command.
9296 =item 1. The original source file itself
9298 =item 2. A file from C<@INC>
9300 =item 3. An C<eval> (the debugger gets a C<(eval N)> fake file for each C<eval>).
9306 if ( $line =~ /^\|*f\s+(.*)/ ) { # Loaded files
9307 # We might possibly want to switch to an eval (which has a "filename"
9308 # like '(eval 9)'), so we may need to clean up the completion text
9309 # before proceeding.
9310 $prefix = length($1) - length($text);
9315 Under the debugger, source files are represented as C<_E<lt>/fullpath/to/file>
9316 (C<eval>s are C<_E<lt>(eval NNN)>) keys in C<%main::>. We pull all of these
9317 out of C<%main::>, add the initial source file, and extract the ones that
9318 match the completion text so far.
9323 map { substr $_, 2 + $prefix } grep /^_<\Q$text/, ( keys %main:: ),
9325 } ## end if ($line =~ /^\|*f\s+(.*)/)
9327 =head3 Subroutine name completion
9329 We look through all of the defined subs (the keys of C<%sub>) and
9330 return both all the possible matches to the subroutine name plus
9331 all the matches qualified to the current package.
9335 if ( ( substr $text, 0, 1 ) eq '&' ) { # subroutines
9336 $text = substr $text, 1;
9338 return sort map "$prefix$_", grep /^\Q$text/, ( keys %sub ),
9340 map { /$search/ ? ($1) : () }
9343 } ## end if ((substr $text, 0, ...
9345 =head3 Scalar, array, and hash completion: partially qualified package
9347 Much like the above, except we have to do a little more cleanup:
9351 if ( $text =~ /^[\$@%](.*)::(.*)/ ) { # symbols in a package
9359 Determine the package that the symbol is in. Put it in C<::> (effectively C<main::>) if no package is specified.
9363 $pack = ( $1 eq 'main' ? '' : $1 ) . '::';
9369 Figure out the prefix vs. what needs completing.
9373 $prefix = ( substr $text, 0, 1 ) . $1 . '::';
9380 Look through all the symbols in the package. C<grep> out all the possible hashes/arrays/scalars, and then C<grep> the possible matches out of those. C<map> the prefix onto all the possibilities.
9386 map "$prefix$_", grep /^\Q$text/, grep /^_?[a-zA-Z]/,
9394 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.
9398 if ( @out == 1 and $out[0] =~ /::$/ and $out[0] ne $itext ) {
9399 return db_complete( $out[0], $line, $start );
9402 # Return the list of possibles.
9405 } ## end if ($text =~ /^[\$@%](.*)::(.*)/)
9411 =head3 Symbol completion: current package or package C<main>.
9415 if ( $text =~ /^[\$@%]/ ) { # symbols (in $package + packages in main)
9422 If it's C<main>, delete main to just get C<::> leading.
9426 $pack = ( $package eq 'main' ? '' : $package ) . '::';
9432 We set the prefix to the item's sigil, and trim off the sigil to get the text to be completed.
9436 $prefix = substr $text, 0, 1;
9437 $text = substr $text, 1;
9445 We look for the lexical scope above DB::DB and auto-complete lexical variables
9446 if PadWalker could be loaded.
9450 if (not $text =~ /::/ and eval {
9452 pop @INC if $INC[-1] eq '.';
9453 require PadWalker } ) {
9456 my @info = caller($level);
9460 last if $info[3] eq 'DB::DB';
9463 my $lexicals = PadWalker::peek_my($level);
9464 push @out, grep /^\Q$prefix$text/, keys %$lexicals;
9472 If the package is C<::> (C<main>), create an empty list; if it's something else, create a list of all the packages known. Append whichever list to a list of all the possible symbols in the current package. C<grep> out the matches to the text entered so far, then C<map> the prefix back onto the symbols.
9476 push @out, map "$prefix$_", grep /^\Q$text/,
9477 ( grep /^_?[a-zA-Z]/, do { no strict 'refs'; keys %$pack } ),
9478 ( $pack eq '::' ? () : ( grep /::$/, keys %:: ) );
9482 If there's only one hit, it's a package qualifier, and it's not equal to the initial text, recomplete using this symbol.
9488 if ( @out == 1 and $out[0] =~ /::$/ and $out[0] ne $itext ) {
9489 return db_complete( $out[0], $line, $start );
9492 # Return the list of possibles.
9494 } ## end if ($text =~ /^[\$@%]/)
9498 We use C<option_val()> to look up the current value of the option. If there's
9499 only a single value, we complete the command in such a way that it is a
9500 complete command for setting the option in question. If there are multiple
9501 possible values, we generate a command consisting of the option plus a trailing
9502 question mark, which, if executed, will list the current value of the option.
9506 if ( ( substr $line, 0, $start ) =~ /^\|*[oO]\b.*\s$/ )
9507 { # Options after space
9508 # We look for the text to be matched in the list of possible options,
9509 # and fetch the current value.
9510 my @out = grep /^\Q$text/, @options;
9511 my $val = option_val( $out[0], undef );
9513 # Set up a 'query option's value' command.
9515 if ( not defined $val or $val =~ /[\n\r]/ ) {
9517 # There's really nothing else we can do.
9520 # We have a value. Create a proper option-setting command.
9521 elsif ( $val =~ /\s/ ) {
9523 # XXX This may be an extraneous variable.
9526 # We'll want to quote the string (because of the embedded
9527 # whtespace), but we want to make sure we don't end up with
9528 # mismatched quote characters. We try several possibilities.
9529 foreach my $l ( split //, qq/\"\'\#\|/ ) {
9531 # If we didn't find this quote character in the value,
9532 # quote it using this quote character.
9533 $out = "$l$val$l ", last if ( index $val, $l ) == -1;
9535 } ## end elsif ($val =~ /\s/)
9537 # Don't need any quotes.
9542 # If there were multiple possible values, return '? ', which
9543 # makes the command into a query command. If there was just one,
9544 # have readline append that.
9545 $rl_attribs->{completer_terminator_character} =
9546 ( @out == 1 ? $out : '? ' );
9548 # Return list of possibilities.
9550 } ## end if ((substr $line, 0, ...
9552 =head3 Filename completion
9554 For entering filenames. We simply call C<readline>'s C<filename_list()>
9555 method with the completion text to get the possible completions.
9559 return $term->filename_list($text); # filenames
9561 } ## end sub db_complete
9563 =head1 MISCELLANEOUS SUPPORT FUNCTIONS
9565 Functions that possibly ought to be somewhere else.
9575 print $OUT "Use 'q' to quit or 'R' to restart. 'h q' for details.\n";
9580 If we have $ini_pids, save it in the environment; else remove it from the
9581 environment. Used by the C<R> (restart) command.
9586 if ( defined($ini_pids) ) {
9587 $ENV{PERLDB_PIDS} = $ini_pids;
9590 delete( $ENV{PERLDB_PIDS} );
9592 } ## end sub clean_ENV
9594 # PERLDBf_... flag names from perl.h
9595 our ( %DollarCaretP_flags, %DollarCaretP_flags_r );
9598 %DollarCaretP_flags = (
9599 PERLDBf_SUB => 0x01, # Debug sub enter/exit
9600 PERLDBf_LINE => 0x02, # Keep line #
9601 PERLDBf_NOOPT => 0x04, # Switch off optimizations
9602 PERLDBf_INTER => 0x08, # Preserve more data
9603 PERLDBf_SUBLINE => 0x10, # Keep subr source lines
9604 PERLDBf_SINGLE => 0x20, # Start with single-step on
9605 PERLDBf_NONAME => 0x40, # For _SUB: no name of the subr
9606 PERLDBf_GOTO => 0x80, # Report goto: call DB::goto
9607 PERLDBf_NAMEEVAL => 0x100, # Informative names for evals
9608 PERLDBf_NAMEANON => 0x200, # Informative names for anon subs
9609 PERLDBf_SAVESRC => 0x400, # Save source lines into @{"_<$filename"}
9610 PERLDB_ALL => 0x33f, # No _NONAME, _GOTO
9612 # PERLDBf_LINE also enables the actions of PERLDBf_SAVESRC, so the debugger
9613 # doesn't need to set it. It's provided for the benefit of profilers and
9614 # other code analysers.
9616 %DollarCaretP_flags_r = reverse %DollarCaretP_flags;
9619 sub parse_DollarCaretP_flags {
9624 foreach my $f ( split /\s*\|\s*/, $flags ) {
9626 if ( $f =~ /^0x([[:xdigit:]]+)$/ ) {
9629 elsif ( $f =~ /^(\d+)$/ ) {
9632 elsif ( $f =~ /^DEFAULT$/i ) {
9633 $value = $DollarCaretP_flags{PERLDB_ALL};
9636 $f =~ /^(?:PERLDBf_)?(.*)$/i;
9637 $value = $DollarCaretP_flags{ 'PERLDBf_' . uc($1) };
9638 unless ( defined $value ) {
9640 "Unrecognized \$^P flag '$f'!\n",
9641 "Acceptable flags are: "
9642 . join( ', ', sort keys %DollarCaretP_flags ),
9643 ", and hexadecimal and decimal numbers.\n"
9653 sub expand_DollarCaretP_flags {
9654 my $DollarCaretP = shift;
9657 my $n = ( 1 << $_ );
9658 ( $DollarCaretP & $n )
9659 ? ( $DollarCaretP_flags_r{$n}
9660 || sprintf( '0x%x', $n ) )
9664 return @bits ? join( '|', @bits ) : 0;
9671 Rerun the current session to:
9673 rerun current position
9675 rerun 4 command number 4
9677 rerun -4 current command minus 4 (go back 4 steps)
9679 Whether this always makes sense, in the current context is unknowable, and is
9680 in part left as a useful exercise for the reader. This sub returns the
9681 appropriate arguments to rerun the current session.
9688 pop(@truehist); # strim
9689 unless (defined $truehist[$i]) {
9690 print "Unable to return to non-existent command: $i\n";
9692 $#truehist = ($i < 0 ? $#truehist + $i : $i > 0 ? $i : $#truehist);
9693 my @temp = @truehist; # store
9694 push(@DB::typeahead, @truehist); # saved
9695 @truehist = @hist = (); # flush
9696 @args = restart(); # setup
9697 get_list("PERLDB_HIST"); # clean
9698 set_list("PERLDB_HIST", @temp); # reset
9705 Restarting the debugger is a complex operation that occurs in several phases.
9706 First, we try to reconstruct the command line that was used to invoke Perl
9712 # I may not be able to resurrect you, but here goes ...
9714 "Warning: some settings and command-line options may be lost!\n";
9715 my ( @script, @flags, $cl );
9717 # If warn was on before, turn it on again.
9718 push @flags, '-w' if $ini_warn;
9720 # Rebuild the -I flags that were on the initial
9723 push @flags, '-I', $_;
9726 # Turn on taint if it was on before.
9727 push @flags, '-T' if ${^TAINT};
9729 # Arrange for setting the old INC:
9730 # Save the current @init_INC in the environment.
9731 set_list( "PERLDB_INC", @ini_INC );
9733 # If this was a perl one-liner, go to the "file"
9734 # corresponding to the one-liner read all the lines
9735 # out of it (except for the first one, which is going
9736 # to be added back on again when 'perl -d' runs: that's
9737 # the 'require perl5db.pl;' line), and add them back on
9738 # to the command line to be executed.
9740 my $lines = *{$main::{'_<-e'}}{ARRAY};
9741 for ( 1 .. $#$lines ) { # The first line is PERL5DB
9742 chomp( $cl = $lines->[$_] );
9743 push @script, '-e', $cl;
9745 } ## end if ($0 eq '-e')
9747 # Otherwise we just reuse the original name we had
9755 After the command line has been reconstructed, the next step is to save
9756 the debugger's status in environment variables. The C<DB::set_list> routine
9757 is used to save aggregate variables (both hashes and arrays); scalars are
9758 just popped into environment variables directly.
9762 # If the terminal supported history, grab it and
9763 # save that in the environment.
9764 set_list( "PERLDB_HIST",
9765 $term->Features->{getHistory}
9769 # Find all the files that were visited during this
9770 # session (i.e., the debugger had magic hashes
9771 # corresponding to them) and stick them in the environment.
9772 my @had_breakpoints = keys %had_breakpoints;
9773 set_list( "PERLDB_VISITED", @had_breakpoints );
9775 # Save the debugger options we chose.
9776 set_list( "PERLDB_OPT", %option );
9777 # set_list( "PERLDB_OPT", options2remember() );
9779 # Save the break-on-loads.
9780 set_list( "PERLDB_ON_LOAD", %break_on_load );
9784 The most complex part of this is the saving of all of the breakpoints. They
9785 can live in an awful lot of places, and we have to go through all of them,
9786 find the breakpoints, and then save them in the appropriate environment
9787 variable via C<DB::set_list>.
9791 # Go through all the breakpoints and make sure they're
9794 for ( 0 .. $#had_breakpoints ) {
9796 # We were in this file.
9797 my $file = $had_breakpoints[$_];
9799 # Grab that file's magic line hash.
9800 *dbline = $main::{ '_<' . $file };
9802 # Skip out if it doesn't exist, or if the breakpoint
9803 # is in a postponed file (we'll do postponed ones
9805 next unless %dbline or $postponed_file{$file};
9807 # In an eval. This is a little harder, so we'll
9808 # do more processing on that below.
9809 ( push @hard, $file ), next
9810 if $file =~ /^\(\w*eval/;
9812 # XXX I have no idea what this is doing. Yet.
9814 @add = %{ $postponed_file{$file} }
9815 if $postponed_file{$file};
9817 # Save the list of all the breakpoints for this file.
9818 set_list( "PERLDB_FILE_$_", %dbline, @add );
9820 # Serialize the extra data %breakpoints_data hash.
9822 set_list( "PERLDB_FILE_ENABLED_$_",
9823 map { _is_breakpoint_enabled($file, $_) ? 1 : 0 }
9824 sort { $a <=> $b } keys(%dbline)
9826 } ## end for (0 .. $#had_breakpoints)
9828 # The breakpoint was inside an eval. This is a little
9829 # more difficult. XXX and I don't understand it.
9830 foreach my $hard_file (@hard) {
9831 # Get over to the eval in question.
9832 *dbline = $main::{ '_<' . $hard_file };
9833 my $quoted = quotemeta $hard_file;
9835 for my $sub ( keys %sub ) {
9836 if (my ($n1, $n2) = $sub{$sub} =~ /\A$quoted:(\d+)-(\d+)\z/) {
9837 $subs{$sub} = [ $n1, $n2 ];
9842 "No subroutines in $hard_file, ignoring breakpoints.\n";
9845 LINES: foreach my $line ( keys %dbline ) {
9847 # One breakpoint per sub only:
9848 my ( $offset, $found );
9849 SUBS: foreach my $sub ( keys %subs ) {
9851 $subs{$sub}->[1] >= $line # Not after the subroutine
9853 not defined $offset # Not caught
9859 $offset = $line - $subs{$sub}->[0];
9861 $offset = "+$offset";
9864 } ## end if ($subs{$sub}->[1] >=...
9865 } ## end for $sub (keys %subs)
9866 if ( defined $offset ) {
9867 $postponed{$found} =
9868 "break $offset if $dbline{$line}";
9872 ("Breakpoint in ${hard_file}:$line ignored:"
9873 . " after all the subroutines.\n");
9875 } ## end for $line (keys %dbline)
9876 } ## end for (@hard)
9878 # Save the other things that don't need to be
9880 set_list( "PERLDB_POSTPONE", %postponed );
9881 set_list( "PERLDB_PRETYPE", @$pretype );
9882 set_list( "PERLDB_PRE", @$pre );
9883 set_list( "PERLDB_POST", @$post );
9884 set_list( "PERLDB_TYPEAHEAD", @typeahead );
9886 # We are officially restarting.
9887 $ENV{PERLDB_RESTART} = 1;
9889 # We are junking all child debuggers.
9890 delete $ENV{PERLDB_PIDS}; # Restore ini state
9892 # Set this back to the initial pid.
9893 $ENV{PERLDB_PIDS} = $ini_pids if defined $ini_pids;
9897 After all the debugger status has been saved, we take the command we built up
9898 and then return it, so we can C<exec()> it. The debugger will spot the
9899 C<PERLDB_RESTART> environment variable and realize it needs to reload its state
9900 from the environment.
9904 # And run Perl again. Add the "-d" flag, all the
9905 # flags we built up, the script (whether a one-liner
9906 # or a file), add on the -emacs flag for a slave editor,
9907 # and then the old arguments.
9909 return ($^X, '-d', @flags, @script, ($slave_editor ? '-emacs' : ()), @ARGS);
9915 =head1 END PROCESSING - THE C<END> BLOCK
9917 Come here at the very end of processing. We want to go into a
9918 loop where we allow the user to enter commands and interact with the
9919 debugger, but we don't want anything else to execute.
9921 First we set the C<$finished> variable, so that some commands that
9922 shouldn't be run after the end of program quit working.
9924 We then figure out whether we're truly done (as in the user entered a C<q>
9925 command, or we finished execution while running nonstop). If we aren't,
9926 we set C<$single> to 1 (causing the debugger to get control again).
9928 We then call C<DB::fake::at_exit()>, which returns the C<Use 'q' to quit ...>
9929 message and returns control to the debugger. Repeat.
9931 When the user finally enters a C<q> command, C<$fall_off_end> is set to
9932 1 and the C<END> block simply exits with C<$single> set to 0 (don't
9933 break, run to completion.).
9938 $finished = 1 if $inhibit_exit; # So that some commands may be disabled.
9939 $fall_off_end = 1 unless $inhibit_exit;
9941 # Do not stop in at_exit() and destructors on exit:
9942 if ($fall_off_end or $runnonstop) {
9946 DB::fake::at_exit();
9950 =head1 PRE-5.8 COMMANDS
9952 Some of the commands changed function quite a bit in the 5.8 command
9953 realignment, so much so that the old code had to be replaced completely.
9954 Because we wanted to retain the option of being able to go back to the
9955 former command set, we moved the old code off to this section.
9957 There's an awful lot of duplicated code here. We've duplicated the
9958 comments to keep things clear.
9962 Does nothing. Used to I<turn off> commands.
9966 sub cmd_pre580_null {
9971 =head2 Old C<a> command.
9973 This version added actions if you supplied them, and deleted them
9982 # Argument supplied. Add the action.
9983 if ( $cmd =~ /^(\d*)\s*(.*)/ ) {
9985 # If the line isn't there, use the current line.
9986 my $i = $1 || $line;
9989 # If there is an action ...
9992 # ... but the line isn't breakable, skip it.
9993 if ( $dbline[$i] == 0 ) {
9994 print $OUT "Line $i may not have an action.\n";
9998 # ... and the line is breakable:
9999 # Mark that there's an action in this file.
10000 $had_breakpoints{$filename} |= 2;
10002 # Delete any current action.
10003 $dbline{$i} =~ s/\0[^\0]*//;
10005 # Add the new action, continuing the line as needed.
10006 $dbline{$i} .= "\0" . action($j);
10008 } ## end if (length $j)
10010 # No action supplied.
10013 # Delete the action.
10014 $dbline{$i} =~ s/\0[^\0]*//;
10016 # Mark as having no break or action if nothing's left.
10017 delete $dbline{$i} if $dbline{$i} eq '';
10019 } ## end if ($cmd =~ /^(\d*)\s*(.*)/)
10020 } ## end sub cmd_pre580_a
10022 =head2 Old C<b> command
10031 my $dbline = shift;
10034 if ( $cmd =~ /^load\b\s*(.*)/ ) {
10040 # b compile|postpone <some sub> [<condition>]
10041 # The interpreter actually traps this one for us; we just put the
10042 # necessary condition in the %postponed hash.
10043 elsif ( $cmd =~ /^(postpone|compile)\b\s*([':A-Za-z_][':\w]*)\s*(.*)/ ) {
10045 # Capture the condition if there is one. Make it true if none.
10046 my $cond = length $3 ? $3 : '1';
10048 # Save the sub name and set $break to 1 if $1 was 'postpone', 0
10049 # if it was 'compile'.
10050 my ( $subname, $break ) = ( $2, $1 eq 'postpone' );
10052 # De-Perl4-ify the name - ' separators to ::.
10053 $subname =~ s/\'/::/g;
10055 # Qualify it into the current package unless it's already qualified.
10056 $subname = "${package}::" . $subname
10057 unless $subname =~ /::/;
10059 # Add main if it starts with ::.
10060 $subname = "main" . $subname if substr( $subname, 0, 2 ) eq "::";
10062 # Save the break type for this sub.
10063 $postponed{$subname} = $break ? "break +0 if $cond" : "compile";
10064 } ## end elsif ($cmd =~ ...
10066 # b <sub name> [<condition>]
10067 elsif ( $cmd =~ /^([':A-Za-z_][':\w]*(?:\[.*\])?)\s*(.*)/ ) {
10069 my $cond = length $2 ? $2 : '1';
10070 cmd_b_sub( $subname, $cond );
10072 # b <line> [<condition>].
10073 elsif ( $cmd =~ /^(\d*)\s*(.*)/ ) {
10074 my $i = $1 || $dbline;
10075 my $cond = length $2 ? $2 : '1';
10076 cmd_b_line( $i, $cond );
10078 } ## end sub cmd_pre580_b
10080 =head2 Old C<D> command.
10082 Delete all breakpoints unconditionally.
10089 if ( $cmd =~ /^\s*$/ ) {
10090 print $OUT "Deleting all breakpoints...\n";
10092 # %had_breakpoints lists every file that had at least one
10093 # breakpoint in it.
10095 for $file ( keys %had_breakpoints ) {
10097 # Switch to the desired file temporarily.
10098 local *dbline = $main::{ '_<' . $file };
10103 # For all lines in this file ...
10104 for my $i (1 .. $max) {
10106 # If there's a breakpoint or action on this line ...
10107 if ( defined $dbline{$i} ) {
10109 # ... remove the breakpoint.
10110 $dbline{$i} =~ s/^[^\0]+//;
10111 if ( $dbline{$i} =~ s/^\0?$// ) {
10113 # Remove the entry altogether if no action is there.
10114 delete $dbline{$i};
10116 } ## end if (defined $dbline{$i...
10117 } ## end for my $i (1 .. $max)
10119 # If, after we turn off the "there were breakpoints in this file"
10120 # bit, the entry in %had_breakpoints for this file is zero,
10121 # we should remove this file from the hash.
10122 if ( not $had_breakpoints{$file} &= ~1 ) {
10123 delete $had_breakpoints{$file};
10125 } ## end for $file (keys %had_breakpoints)
10127 # Kill off all the other breakpoints that are waiting for files that
10128 # haven't been loaded yet.
10130 undef %postponed_file;
10131 undef %break_on_load;
10132 } ## end if ($cmd =~ /^\s*$/)
10133 } ## end sub cmd_pre580_D
10135 =head2 Old C<h> command
10137 Print help. Defaults to printing the long-form help; the 5.8 version
10138 prints the summary by default.
10146 # Print the *right* help, long format.
10147 if ( $cmd =~ /^\s*$/ ) {
10148 print_help($pre580_help);
10151 # 'h h' - explicitly-requested summary.
10152 elsif ( $cmd =~ /^h\s*/ ) {
10153 print_help($pre580_summary);
10156 # Find and print a command's help.
10157 elsif ( $cmd =~ /^h\s+(\S.*)$/ ) {
10158 my $asked = $1; # for proper errmsg
10159 my $qasked = quotemeta($asked); # for searching
10160 # XXX: finds CR but not <CR>
10164 (?:[IB]<) # Optional markup
10165 $qasked # The command name
10172 ( # The command help:
10174 (?:[IB]<) # Optional markup
10175 $qasked # The command name
10176 ([\s\S]*?) # Lines starting with tabs
10180 ) # Line not starting with space
10181 # (Next command's help)
10185 } ## end if ($pre580_help =~ /^<?(?:[IB]<)$qasked/m)
10189 print_help("B<$asked> is not a debugger command.\n");
10191 } ## end elsif ($cmd =~ /^h\s+(\S.*)$/)
10192 } ## end sub cmd_pre580_h
10194 =head2 Old C<W> command
10196 C<W E<lt>exprE<gt>> adds a watch expression, C<W> deletes them all.
10204 # Delete all watch expressions.
10205 if ( $cmd =~ /^$/ ) {
10207 # No watching is going on.
10210 # Kill all the watch expressions and values.
10211 @to_watch = @old_watch = ();
10214 # Add a watch expression.
10215 elsif ( $cmd =~ /^(.*)/s ) {
10217 # add it to the list to be watched.
10218 push @to_watch, $1;
10220 # Get the current value of the expression.
10221 # Doesn't handle expressions returning list values!
10223 # The &-call is here to ascertain the mutability of @_.
10224 my ($val) = &DB::eval;
10225 $val = ( defined $val ) ? "'$val'" : 'undef';
10228 push @old_watch, $val;
10230 # We're watching stuff.
10233 } ## end elsif ($cmd =~ /^(.*)/s)
10234 } ## end sub cmd_pre580_W
10236 =head1 PRE-AND-POST-PROMPT COMMANDS AND ACTIONS
10238 The debugger used to have a bunch of nearly-identical code to handle
10239 the pre-and-post-prompt action commands. C<cmd_pre590_prepost> and
10240 C<cmd_prepost> unify all this into one set of code to handle the
10241 appropriate actions.
10243 =head2 C<cmd_pre590_prepost>
10245 A small wrapper around C<cmd_prepost>; it makes sure that the default doesn't
10246 do something destructive. In pre 5.8 debuggers, the default action was to
10247 delete all the actions.
10251 sub cmd_pre590_prepost {
10253 my $line = shift || '*';
10254 my $dbline = shift;
10256 return cmd_prepost( $cmd, $line, $dbline );
10257 } ## end sub cmd_pre590_prepost
10259 =head2 C<cmd_prepost>
10261 Actually does all the handling for C<E<lt>>, C<E<gt>>, C<{{>, C<{>, etc.
10262 Since the lists of actions are all held in arrays that are pointed to by
10263 references anyway, all we have to do is pick the right array reference and
10264 then use generic code to all, delete, or list actions.
10271 # No action supplied defaults to 'list'.
10272 my $line = shift || '?';
10274 # Figure out what to put in the prompt.
10277 # Make sure we have some array or another to address later.
10278 # This means that if for some reason the tests fail, we won't be
10279 # trying to stash actions or delete them from the wrong place.
10282 # < - Perl code to run before prompt.
10283 if ( $cmd =~ /^\</o ) {
10284 $which = 'pre-perl';
10288 # > - Perl code to run after prompt.
10289 elsif ( $cmd =~ /^\>/o ) {
10290 $which = 'post-perl';
10294 # { - first check for properly-balanced braces.
10295 elsif ( $cmd =~ /^\{/o ) {
10296 if ( $cmd =~ /^\{.*\}$/o && unbalanced( substr( $cmd, 1 ) ) ) {
10298 "$cmd is now a debugger command\nuse ';$cmd' if you mean Perl code\n";
10301 # Properly balanced. Pre-prompt debugger actions.
10303 $which = 'pre-debugger';
10306 } ## end elsif ( $cmd =~ /^\{/o )
10308 # Did we find something that makes sense?
10310 print $OUT "Confused by command: $cmd\n";
10317 if ( $line =~ /^\s*\?\s*$/o ) {
10320 # Nothing there. Complain.
10321 print $OUT "No $which actions.\n";
10325 # List the actions in the selected list.
10326 print $OUT "$which commands:\n";
10327 foreach my $action (@$aref) {
10328 print $OUT "\t$cmd -- $action\n";
10331 } ## end if ( $line =~ /^\s*\?\s*$/o)
10333 # Might be a delete.
10335 if ( length($cmd) == 1 ) {
10336 if ( $line =~ /^\s*\*\s*$/o ) {
10338 # It's a delete. Get rid of the old actions in the
10341 print $OUT "All $cmd actions cleared.\n";
10345 # Replace all the actions. (This is a <, >, or {).
10346 @$aref = action($line);
10348 } ## end if ( length($cmd) == 1)
10349 elsif ( length($cmd) == 2 ) {
10351 # Add the action to the line. (This is a <<, >>, or {{).
10352 push @$aref, action($line);
10356 # <<<, >>>>, {{{{{{ ... something not a command.
10358 "Confused by strange length of $which command($cmd)...\n";
10360 } ## end else [ if ( $line =~ /^\s*\?\s*$/o)
10362 } ## end sub cmd_prepost
10366 Contains the C<at_exit> routine that the debugger uses to issue the
10367 C<Debugged program terminated ...> message after the program completes. See
10368 the C<END> block documentation for more details.
10375 "Debugged program terminated. Use 'q' to quit or 'R' to restart.";
10378 package DB; # Do not trace this 1; below!