package re;
-$VERSION = 0.02;
+our $VERSION = 0.06_03;
=head1 NAME
/foo${pat}bar/; # disallowed (with or without -T switch)
}
- use re 'debug'; # NOT lexically scoped (as others are)
- /^(.*)$/s; # output debugging info during
- # compile and run time
+ use re 'debug'; # output debugging info during
+ /^(.*)$/s; # compile and run time
+
+
+ use re 'debugcolor'; # same as 'debug', but with colored output
+ ...
+
+ use re qw(Debug All); # Finer tuned debugging options.
+ use re qw(Debug More);
+ no re qw(Debug ALL); # Turn of all re debugging in this scope
(We use $^X in these examples because it's tainted by default.)
When C<use re 'eval'> is in effect, a regex is allowed to contain
C<(?{ ... })> zero-width assertions even if regular expression contains
-variable interpolation. That is normally disallowed, since it is a
+variable interpolation. That is normally disallowed, since it is a
potential security risk. Note that this pragma is ignored when the regular
expression is obtained from tainted data, i.e. evaluation is always
-disallowed with tainted regular expresssions. See L<perlre/(?{ code })>.
+disallowed with tainted regular expressions. See L<perlre/(?{ code })>.
-For the purpose of this pragma, interpolation of precompiled regular
+For the purpose of this pragma, interpolation of precompiled regular
expressions (i.e., the result of C<qr//>) is I<not> considered variable
interpolation. Thus:
/foo${pat}bar/
-I<is> allowed if $pat is a precompiled regular expression, even
+I<is> allowed if $pat is a precompiled regular expression, even
if $pat contains C<(?{ ... })> assertions.
-When C<use re 'debug'> is in effect, perl emits debugging messages when
+When C<use re 'debug'> is in effect, perl emits debugging messages when
compiling and using regular expressions. The output is the same as that
obtained by running a C<-DDEBUGGING>-enabled perl interpreter with the
B<-Dr> switch. It may be quite voluminous depending on the complexity
-of the match.
+of the match. Using C<debugcolor> instead of C<debug> enables a
+form of output that can be used to get a colorful display on terminals
+that understand termcap color sequences. Set C<$ENV{PERL_RE_TC}> to a
+comma-separated list of C<termcap> properties to use for highlighting
+strings on/off, pre-point part on/off.
See L<perldebug/"Debugging regular expressions"> for additional info.
-The directive C<use re 'debug'> is I<not lexically scoped>, as the
-other directives are. It has both compile-time and run-time effects.
+Similarly C<use re 'Debug'> produces debugging output, the difference
+being that it allows the fine tuning of what debugging output will be
+emitted. Options are divided into three groups, those related to
+compilation, those related to execution and those related to special
+purposes. The options are as follows:
+
+=over 4
+
+=item Compile related options
+
+=over 4
+
+=item COMPILE
+
+Turns on all compile related debug options.
+
+=item PARSE
+
+Turns on debug output related to the process of parsing the pattern.
+
+=item OPTIMISE
+
+Enables output related to the optimisation phase of compilation.
+
+=item TRIEC
+
+Detailed info about trie compilation.
+
+=item DUMP
+
+Dump the final program out after it is compiled and optimised.
+
+
+=back
+
+=item Execute related options
+
+=over 4
+
+=item EXECUTE
+
+Turns on all execute related debug options.
+
+=item MATCH
+
+Turns on debugging of the main matching loop.
+
+=item TRIEE
+
+Extra debugging of how tries execute.
+
+=item INTUIT
+
+Enable debugging of start point optimisations.
+
+=back
+
+=item Extra debugging options
+
+=over 4
+
+=item EXTRA
+
+Turns on all "extra" debugging options.
+
+=item TRIEM
+
+Enable enhanced TRIE debugging. Enhances both TRIEE
+and TRIEC.
+
+=item STATE
+
+Enable debugging of states in the engine.
+
+=item STACK
+
+Enable debugging of the recursion stack in the engine. Enabling
+or disabling this option automatically does the same for debugging
+states as well. This output from this can be quite large.
+
+=item OPTIMISEM
+
+Enable enhanced optimisation debugging and start point optimisations.
+Probably not useful except when debugging the regex engine itself.
+
+=item OFFSETS
+
+Dump offset information. This can be used to see how regops correlate
+to the pattern. Output format is
+
+ NODENUM:POSITION[LENGTH]
+
+Where 1 is the position of the first char in the string. Note that position
+can be 0, or larger than the actual length of the pattern, likewise length
+can be zero.
+
+=item OFFSETSDBG
+
+Enable debugging of offsets information. This emits copious
+amounts of trace information and doesn't mesh well with other
+debug options.
+
+Almost definitely only useful to people hacking
+on the offsets part of the debug engine.
+
+=back
+
+=item Other useful flags
+
+These are useful shortcuts to save on the typing.
+
+=over 4
+
+=item ALL
+
+Enable all compile and execute options at once.
+
+=item All
+
+Enable DUMP and all execute options. Equivalent to:
+
+ use re 'debug';
+
+=item MORE
+
+=item More
+
+Enable TRIEM and all execute compile and execute options.
+
+=back
+
+=back
+
+As of 5.9.5 the directive C<use re 'debug'> and its equivalents are
+lexically scoped, as the other directives are. However they have both
+compile-time and run-time effects.
See L<perlmodlib/Pragmatic Modules>.
=cut
+# N.B. File::Basename contains a literal for 'taint' as a fallback. If
+# taint is changed here, File::Basename must be updated as well.
my %bitmask = (
-taint => 0x00100000,
-eval => 0x00200000,
+taint => 0x00100000, # HINT_RE_TAINT
+eval => 0x00200000, # HINT_RE_EVAL
);
+sub setcolor {
+ eval { # Ignore errors
+ require Term::Cap;
+
+ my $terminal = Tgetent Term::Cap ({OSPEED => 9600}); # Avoid warning.
+ my $props = $ENV{PERL_RE_TC} || 'md,me,so,se,us,ue';
+ my @props = split /,/, $props;
+ my $colors = join "\t", map {$terminal->Tputs($_,1)} @props;
+
+ $colors =~ s/\0//g;
+ $ENV{PERL_RE_COLORS} = $colors;
+ };
+ if ($@) {
+ $ENV{PERL_RE_COLORS}||=qq'\t\t> <\t> <\t\t'
+ }
+
+}
+
+my %flags = (
+ COMPILE => 0x0000FF,
+ PARSE => 0x000001,
+ OPTIMISE => 0x000002,
+ TRIEC => 0x000004,
+ DUMP => 0x000008,
+
+ EXECUTE => 0x00FF00,
+ INTUIT => 0x000100,
+ MATCH => 0x000200,
+ TRIEE => 0x000400,
+
+ EXTRA => 0xFF0000,
+ TRIEM => 0x010000,
+ OFFSETS => 0x020000,
+ OFFSETSDBG => 0x040000,
+ STATE => 0x080000,
+ OPTIMISEM => 0x100000,
+ STACK => 0x280000,
+);
+$flags{ALL} = -1;
+$flags{All} = $flags{all} = $flags{DUMP} | $flags{EXECUTE};
+$flags{Extra} = $flags{EXECUTE} | $flags{COMPILE};
+$flags{More} = $flags{MORE} = $flags{All} | $flags{TRIEC} | $flags{TRIEM} | $flags{STATE};
+$flags{State} = $flags{DUMP} | $flags{EXECUTE} | $flags{STATE};
+$flags{TRIE} = $flags{DUMP} | $flags{EXECUTE} | $flags{TRIEC};
+
+my $installed;
+my $installed_error;
+
+sub _load_unload {
+ my ($on)= @_;
+ if ($on) {
+ if ( ! defined($installed) ) {
+ require XSLoader;
+ $installed = eval { XSLoader::load('re') } || 0;
+ $installed_error = $@;
+ }
+ if ( ! $installed ) {
+ die "'re' not installed!? ($installed_error)";
+ } else {
+ # We call install() every time, as if we didn't, we wouldn't
+ # "see" any changes to the color environment var since
+ # the last time it was called.
+
+ # install() returns an integer, which if casted properly
+ # in C resolves to a structure containing the regex
+ # hooks. Setting it to a random integer will guarantee
+ # segfaults.
+ $^H{regcomp} = install();
+ }
+ } else {
+ delete $^H{regcomp};
+ }
+}
+
sub bits {
my $on = shift;
my $bits = 0;
- unless(@_) {
+ unless (@_) {
require Carp;
Carp::carp("Useless use of \"re\" pragma");
}
- foreach my $s (@_){
- if ($s eq 'debug') {
- eval <<'EOE';
- use DynaLoader;
- @ISA = ('DynaLoader');
- bootstrap re;
-EOE
- install() if $on;
- uninstall() unless $on;
- next;
- }
- $bits |= $bitmask{$s} || 0;
+ foreach my $idx (0..$#_){
+ my $s=$_[$idx];
+ if ($s eq 'Debug' or $s eq 'Debugcolor') {
+ setcolor() if $s =~/color/i;
+ ${^RE_DEBUG_FLAGS} = 0 unless defined ${^RE_DEBUG_FLAGS};
+ for my $idx ($idx+1..$#_) {
+ if ($flags{$_[$idx]}) {
+ if ($on) {
+ ${^RE_DEBUG_FLAGS} |= $flags{$_[$idx]};
+ } else {
+ ${^RE_DEBUG_FLAGS} &= ~ $flags{$_[$idx]};
+ }
+ } else {
+ require Carp;
+ Carp::carp("Unknown \"re\" Debug flag '$_[$idx]', possible flags: ",
+ join(", ",sort keys %flags ) );
+ }
+ }
+ _load_unload($on ? 1 : ${^RE_DEBUG_FLAGS});
+ last;
+ } elsif ($s eq 'debug' or $s eq 'debugcolor') {
+ setcolor() if $s =~/color/i;
+ _load_unload($on);
+ } elsif (exists $bitmask{$s}) {
+ $bits |= $bitmask{$s};
+ } else {
+ require Carp;
+ Carp::carp("Unknown \"re\" subpragma '$s' (known ones are: ",
+ join(', ', map {qq('$_')} 'debug', 'debugcolor', sort keys %bitmask),
+ ")");
+ }
}
$bits;
}
sub import {
shift;
- $^H |= bits(1,@_);
+ $^H |= bits(1, @_);
}
sub unimport {
shift;
- $^H &= ~ bits(0,@_);
+ $^H &= ~ bits(0, @_);
}
1;