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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 1.17 by root, Wed Nov 19 07:36:40 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
… …
107sub track { 109sub track {
108 my ($ref, $depth) = @_; 110 my ($ref, $depth) = @_;
109 @_ = (); 111 @_ = ();
110 112
111 my $buf = ""; 113 my $buf = "";
114 my %seen;
112 115
113 Scalar::Util::weaken $ref; 116 Scalar::Util::weaken $ref;
114 117
115 my $track; $track = sub { 118 my $track; $track = sub {
116 my ($refref, $depth, $indent) = @_; 119 my ($refref, $depth, $indent) = @_;
117 120
118 if ($depth) { 121 if ($depth) {
119 my (@about) = find $$refref; 122 my (@about) = find $$refref;
120 if (@about) { 123 if (@about) {
121 for my $about (@about) { 124 for my $about (@about) {
122 $buf .= (" ") x $indent; 125 $buf .= "$indent" . (@about > 1 ? "+- " : " ") . $about->[0];
123 $buf .= $about->[0];
124 if (@$about > 1) { 126 if (@$about > 1) {
127 if ($seen{ref2ptr $about->[1]}++) {
128 $buf .= " $about->[1], which was seen before.\n";
129 } else {
125 $buf .= " $about->[1], which is\n"; 130 $buf .= " $about->[1], which is\n";
126 $track->(\$about->[1], $depth - 1, $indent + 1); 131 $track->(\$about->[1], $depth - 1, $about == $about[-1] ? "$indent " : "$indent| ");
132 }
127 } else { 133 } else {
128 $buf .= ".\n"; 134 $buf .= ".\n";
129 } 135 }
130 } 136 }
131 } else { 137 } else {
132 $buf .= (" ") x $indent;
133 $buf .= "not found anywhere I looked :(\n"; 138 $buf .= "$indent not found anywhere I looked :(\n";
134 } 139 }
135 } else { 140 } else {
136 $buf .= (" ") x $indent;
137 $buf .= "not referenced within the search depth.\n"; 141 $buf .= "$indent not referenced within the search depth.\n";
138 } 142 }
139 }; 143 };
140 144
141 $buf .= "$ref is\n"; 145 $buf .= "$ref is\n";
142 $track->(\$ref, $depth || 10, 1); 146 $track->(\$ref, $depth || $ENV{PERL_DEVEL_FINDREF_DEPTH} || 10, "");
143 $buf 147 $buf
144} 148}
145 149
146=item @references = Devel::FindRef::find $ref 150=item @references = Devel::FindRef::find $ref
147 151
… …
156=cut 160=cut
157 161
158sub find($) { 162sub find($) {
159 my ($about, $excl) = &find_; 163 my ($about, $excl) = &find_;
160 my %excl = map +($_ => undef), @$excl; 164 my %excl = map +($_ => undef), @$excl;
161 grep !exists $excl{$_->[1] + 0}, @$about 165 grep !exists $excl{ref2ptr $_->[1]}, @$about
162} 166}
163 167
164=item $ref = Devel::FindRef::ptr2ref $integer 168=item $ref = Devel::FindRef::ptr2ref $integer
165 169
166Sometimes you know (from debugging output) the address of a perl scalar 170Sometimes you know (from debugging output) the address of a perl scalar
… …
169call on valid addresses, but extremely dangerous to call on invalid ones. 173call on valid addresses, but extremely dangerous to call on invalid ones.
170 174
171 # we know that HASH(0x176ff70) exists, so turn it into a hashref: 175 # we know that HASH(0x176ff70) exists, so turn it into a hashref:
172 my $ref_to_hash = Devel::FindRef::ptr2ref 0x176ff70; 176 my $ref_to_hash = Devel::FindRef::ptr2ref 0x176ff70;
173 177
178=item $ref = Devel::FindRef::ref2ptr $reference
179
180The opposite of C<ptr2ref>, above: returns the internal address of the
181value pointed to by the passed reference. I<No checks whatsoever will be
182done>, so don't use this.
183
174=back 184=back
175 185
186=head1 ENVIRONMENT VARIABLES
187
188You can set the environment variable C<PERL_DEVEL_FINDREF_DEPTH> to an
189integer to override the default depth in C<track>. If a call explicitly
190specified a depth it is not overridden.
191
176=head1 AUTHOR 192=head1 AUTHOR
177 193
178Marc Lehmann <pcg@goof.com>. 194Marc Lehmann <pcg@goof.com>.
179 195
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 196=head1 COPYRIGHT AND LICENSE
187 197
188Copyright (C) 2007 by Marc Lehmann. 198Copyright (C) 2007, 2008 by Marc Lehmann.
189 199
190This library is free software; you can redistribute it and/or modify 200This 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, 201it 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. 202at your option, any later version of Perl 5 you may have available.
193 203

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