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Comparing Devel-FindRef/FindRef.pm (file contents):
Revision 1.10 by root, Sat Apr 26 03:15:28 2008 UTC vs.
Revision 1.18 by root, Mon Dec 1 13:22:43 2008 UTC

1package Devel::FindRef; 1package Devel::FindRef;
2 2
3no warnings; # I hate warning nazis
3use strict; 4use strict;
4 5
5use XSLoader; 6use XSLoader;
6use Scalar::Util; 7use Scalar::Util;
7 8
8BEGIN { 9BEGIN {
9 our $VERSION = '1.2'; 10 our $VERSION = '1.31';
10 XSLoader::load __PACKAGE__, $VERSION; 11 XSLoader::load __PACKAGE__, $VERSION;
11} 12}
12 13
13=head1 NAME 14=head1 NAME
14 15
15Devel::FindRef - where is that reference to my scalar hiding? 16Devel::FindRef - where is that reference to my variable hiding?
16 17
17=head1 SYNOPSIS 18=head1 SYNOPSIS
18 19
19 use Devel::FindRef; 20 use Devel::FindRef;
21
22 print Devel::FindRef::track \$some_variable;
20 23
21=head1 DESCRIPTION 24=head1 DESCRIPTION
22 25
23Tracking down reference problems (e.g. you expect some object to be 26Tracking down reference problems (e.g. you expect some object to be
24destroyed, but there are still references to it that keep it alive) can be 27destroyed, but there are still references to it that keep it alive) can be
… …
45 testsub; 48 testsub;
46 49
47The output is as follows (or similar to this, in case I forget to update 50The output is as follows (or similar to this, in case I forget to update
48the manpage after some changes): 51the manpage after some changes):
49 52
50 SCALAR(0x7bd2d0) is 53 SCALAR(0x814ece8) is
51 in the global $Test::var. 54 +- in the global $Test::var.
52 referenced by REF(0x7bd240), which is 55 +- referenced by REF(0x814f9e4), which is
53 in the member 'ukukey2' of HASH(0x7bd228), which is
54 referenced by REF(0x81dae8), which is
55 in the lexical '$local' in CODE(0x81da88), which is 56 | in the lexical '$x' in CODE(0x814ed78), which is
57 | the containing scope for CODE(0x820c4b0), which is
56 in the global &Test::testsub. 58 | in the global &Test::testsub.
59 +- referenced by REF(0x814ed6c), which is
60 | in the member 'ukukey' of HASH(0x81da20c), which is
61 | in the global %Test::hash.
62 +- referenced by REF(0x814ec28), which is
63 | not found anywhere I looked :(
64 +- referenced by REF(0x814eb44), which is
65 in the member 'ukukey2' of HASH(0x814f99c), which is
57 referenced by REF(0x81da40), which is 66 +- referenced by REF(0x820c450), which is
67 | in the lexical '$local' in CODE(0x820c4b0), which was seen before.
68 +- referenced by REF(0x820c204), which is
58 in the global $Test::hash2. 69 in the global $Test::hash2.
59 referenced by REF(0x79f3f8), which is
60 in the lexical '$x' in CODE(0x79f518), which is
61 the containing scope for CODE(0x81da88), which is
62 in the global &Test::testsub.
63 referenced by REF(0x79f2f0), which is
64 not found anywhere I looked :(
65 referenced by REF(0x79f140), which is
66 in the member 'ukukey' of HASH(0x81d698), which is
67 in the global %Test::hash.
68 70
69It is a bit convoluted to read, but basically it says that the value 71It is a bit convoluted to read, but basically it says that the value
70stored in C<$var> can be found: 72stored in C<$var> can be found:
71 73
72=over 4 74=over 4
… …
102 104
103=cut 105=cut
104 106
105sub find($); 107sub find($);
106 108
109sub _f($) {
110 "$_[0] [refcount " . (_refcnt $_[0]) . "]"
111}
112
107sub track { 113sub track {
108 my ($ref, $depth) = @_; 114 my ($ref, $depth) = @_;
109 @_ = (); 115 @_ = ();
110 116
111 my $buf = ""; 117 my $buf = "";
118 my %seen;
112 119
113 Scalar::Util::weaken $ref; 120 Scalar::Util::weaken $ref;
114 121
115 my $track; $track = sub { 122 my $track; $track = sub {
116 my ($refref, $depth, $indent) = @_; 123 my ($refref, $depth, $indent) = @_;
117 124
118 if ($depth) { 125 if ($depth) {
119 my (@about) = find $$refref; 126 my (@about) = find $$refref;
120 if (@about) { 127 if (@about) {
121 for my $about (@about) { 128 for my $about (@about) {
122 $buf .= (" ") x $indent; 129 $buf .= "$indent" . (@about > 1 ? "+- " : " ") . $about->[0];
123 $buf .= $about->[0];
124 if (@$about > 1) { 130 if (@$about > 1) {
131 if ($seen{ref2ptr $about->[1]}++) {
132 $buf .= " " . (_f $about->[1]) . ", which was seen before.\n";
133 } else {
125 $buf .= " $about->[1], which is\n"; 134 $buf .= " " . (_f $about->[1]) . ", which is\n";
126 $track->(\$about->[1], $depth - 1, $indent + 1); 135 $track->(\$about->[1], $depth - 1, $about == $about[-1] ? "$indent " : "$indent| ");
136 }
127 } else { 137 } else {
128 $buf .= ".\n"; 138 $buf .= ".\n";
129 } 139 }
130 } 140 }
131 } else { 141 } else {
132 $buf .= (" ") x $indent;
133 $buf .= "not found anywhere I looked :(\n"; 142 $buf .= "$indent not found anywhere I looked :(\n";
134 } 143 }
135 } else { 144 } else {
136 $buf .= (" ") x $indent;
137 $buf .= "not referenced within the search depth.\n"; 145 $buf .= "$indent not referenced within the search depth.\n";
138 } 146 }
139 }; 147 };
140 148
141 $buf .= "$ref is\n"; 149 $buf .= (_f $ref) . " is\n";
142 $track->(\$ref, $depth || 10, 1); 150 $track->(\$ref, $depth || $ENV{PERL_DEVEL_FINDREF_DEPTH} || 10, "");
143 $buf 151 $buf
144} 152}
145 153
146=item @references = Devel::FindRef::find $ref 154=item @references = Devel::FindRef::find $ref
147 155
… …
156=cut 164=cut
157 165
158sub find($) { 166sub find($) {
159 my ($about, $excl) = &find_; 167 my ($about, $excl) = &find_;
160 my %excl = map +($_ => undef), @$excl; 168 my %excl = map +($_ => undef), @$excl;
161 grep !exists $excl{$_->[1] + 0}, @$about 169 grep !exists $excl{ref2ptr $_->[1]}, @$about
162} 170}
163 171
164=item $ref = Devel::FindRef::ptr2ref $integer 172=item $ref = Devel::FindRef::ptr2ref $integer
165 173
166Sometimes you know (from debugging output) the address of a perl scalar 174Sometimes you know (from debugging output) the address of a perl scalar
… …
169call on valid addresses, but extremely dangerous to call on invalid ones. 177call on valid addresses, but extremely dangerous to call on invalid ones.
170 178
171 # we know that HASH(0x176ff70) exists, so turn it into a hashref: 179 # we know that HASH(0x176ff70) exists, so turn it into a hashref:
172 my $ref_to_hash = Devel::FindRef::ptr2ref 0x176ff70; 180 my $ref_to_hash = Devel::FindRef::ptr2ref 0x176ff70;
173 181
182=item $ref = Devel::FindRef::ref2ptr $reference
183
184The opposite of C<ptr2ref>, above: returns the internal address of the
185value pointed to by the passed reference. I<No checks whatsoever will be
186done>, so don't use this.
187
174=back 188=back
175 189
190=head1 ENVIRONMENT VARIABLES
191
192You can set the environment variable C<PERL_DEVEL_FINDREF_DEPTH> to an
193integer to override the default depth in C<track>. If a call explicitly
194specified a depth it is not overridden.
195
176=head1 AUTHOR 196=head1 AUTHOR
177 197
178Marc Lehmann <pcg@goof.com>. 198Marc Lehmann <pcg@goof.com>.
179 199
180=head1 BUGS
181
182Only code values, arrays, hashes, scalars and magic are being looked at.
183
184This is a quick hack only.
185
186=head1 COPYRIGHT AND LICENSE 200=head1 COPYRIGHT AND LICENSE
187 201
188Copyright (C) 2007 by Marc Lehmann. 202Copyright (C) 2007, 2008 by Marc Lehmann.
189 203
190This library is free software; you can redistribute it and/or modify 204This library is free software; you can redistribute it and/or modify
191it under the same terms as Perl itself, either Perl version 5.8.8 or, 205it under the same terms as Perl itself, either Perl version 5.8.8 or,
192at your option, any later version of Perl 5 you may have available. 206at your option, any later version of Perl 5 you may have available.
193 207

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