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Comparing Devel-FindRef/FindRef.pm (file contents):
Revision 1.9 by root, Sat Dec 29 21:04:46 2007 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 = '1.1'; 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(0x676fa0) is 53 SCALAR(0x814ece8) is
54 +- in the global $Test::var.
51 referenced by REF(0x676fb0), which is 55 +- referenced by REF(0x814f9e4), which is
52 in the lexical '$x' in CODE(0x676370), which is 56 | in the lexical '$x' in CODE(0x814ed78), which is
53 not found anywhere I looked :( 57 | the containing scope for CODE(0x820c4b0), which is
58 | in the global &Test::testsub.
54 referenced by REF(0x676360), which is 59 +- referenced by REF(0x814ed6c), which is
55 in the member 'ukukey' of HASH(0x756660), which is 60 | in the member 'ukukey' of HASH(0x81da20c), which is
56 in the global %Test::hash. 61 | in the global %Test::hash.
57 in the global $Test::var.
58 referenced by REF(0x6760e0), which is 62 +- referenced by REF(0x814ec28), which is
63 | not found anywhere I looked :(
64 +- referenced by REF(0x814eb44), which is
59 in the member 'ukukey2' of HASH(0x676f30), which is 65 in the member 'ukukey2' of HASH(0x814f99c), which is
60 referenced by REF(0x77bcf0), which is 66 +- referenced by REF(0x820c450), which is
61 in the lexical '$local' in CODE(0x77bcb0), which is 67 | in the lexical '$local' in CODE(0x820c4b0), which was seen before.
62 in the global &Test::testsub.
63 referenced by REF(0x77bc80), which is 68 +- referenced by REF(0x820c204), which is
64 in the global $Test::hash2. 69 in the global $Test::hash2.
65
66 70
67It is a bit convoluted to read, but basically it says that the value 71It is a bit convoluted to read, but basically it says that the value
68stored in C<$var> can be found: 72stored in C<$var> can be found:
69 73
70=over 4 74=over 4
… …
100 104
101=cut 105=cut
102 106
103sub find($); 107sub find($);
104 108
109sub _f($) {
110 "$_[0] [refcount " . (_refcnt $_[0]) . "]"
111}
112
105sub track { 113sub track {
106 my ($ref, $depth) = @_; 114 my ($ref, $depth) = @_;
107 @_ = (); 115 @_ = ();
108 116
109 my $buf = ""; 117 my $buf = "";
118 my %seen;
110 119
111 Scalar::Util::weaken $ref; 120 Scalar::Util::weaken $ref;
112 121
113 my $track; $track = sub { 122 my $track; $track = sub {
114 my ($refref, $depth, $indent) = @_; 123 my ($refref, $depth, $indent) = @_;
115 124
116 if ($depth) { 125 if ($depth) {
117 my (@about) = find $$refref; 126 my (@about) = find $$refref;
118 if (@about) { 127 if (@about) {
119 for my $about (@about) { 128 for my $about (@about) {
120 $buf .= (" ") x $indent; 129 $buf .= "$indent" . (@about > 1 ? "+- " : " ") . $about->[0];
121 $buf .= $about->[0];
122 if (@$about > 1) { 130 if (@$about > 1) {
131 if ($seen{ref2ptr $about->[1]}++) {
132 $buf .= " " . (_f $about->[1]) . ", which was seen before.\n";
133 } else {
123 $buf .= " $about->[1], which is\n"; 134 $buf .= " " . (_f $about->[1]) . ", which is\n";
124 $track->(\$about->[1], $depth - 1, $indent + 1); 135 $track->(\$about->[1], $depth - 1, $about == $about[-1] ? "$indent " : "$indent| ");
136 }
125 } else { 137 } else {
126 $buf .= ".\n"; 138 $buf .= ".\n";
127 } 139 }
128 } 140 }
129 } else { 141 } else {
130 $buf .= (" ") x $indent;
131 $buf .= "not found anywhere I looked :(\n"; 142 $buf .= "$indent not found anywhere I looked :(\n";
132 } 143 }
133 } else { 144 } else {
134 $buf .= (" ") x $indent;
135 $buf .= "not referenced within the search depth.\n"; 145 $buf .= "$indent not referenced within the search depth.\n";
136 } 146 }
137 }; 147 };
138 148
139 $buf .= "$ref is\n"; 149 $buf .= (_f $ref) . " is\n";
140 $track->(\$ref, $depth || 10, 1); 150 $track->(\$ref, $depth || $ENV{PERL_DEVEL_FINDREF_DEPTH} || 10, "");
141 $buf 151 $buf
142} 152}
143 153
144=item @references = Devel::FindRef::find $ref 154=item @references = Devel::FindRef::find $ref
145 155
… …
154=cut 164=cut
155 165
156sub find($) { 166sub find($) {
157 my ($about, $excl) = &find_; 167 my ($about, $excl) = &find_;
158 my %excl = map +($_ => undef), @$excl; 168 my %excl = map +($_ => undef), @$excl;
159 grep !exists $excl{$_->[1] + 0}, @$about 169 grep !exists $excl{ref2ptr $_->[1]}, @$about
160} 170}
161 171
162=item $ref = Devel::FindRef::ptr2ref $integer 172=item $ref = Devel::FindRef::ptr2ref $integer
163 173
164Sometimes you know (from debugging output) the address of a perl scalar 174Sometimes you know (from debugging output) the address of a perl scalar
… …
167call on valid addresses, but extremely dangerous to call on invalid ones. 177call on valid addresses, but extremely dangerous to call on invalid ones.
168 178
169 # 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:
170 my $ref_to_hash = Devel::FindRef::ptr2ref 0x176ff70; 180 my $ref_to_hash = Devel::FindRef::ptr2ref 0x176ff70;
171 181
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
172=back 188=back
173 189
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
174=head1 AUTHOR 196=head1 AUTHOR
175 197
176Marc Lehmann <pcg@goof.com>. 198Marc Lehmann <pcg@goof.com>.
177 199
178=head1 BUGS
179
180Only code values, arrays, hashes, scalars and magic are being looked at.
181
182This is a quick hack only.
183
184=head1 COPYRIGHT AND LICENSE 200=head1 COPYRIGHT AND LICENSE
185 201
186Copyright (C) 2007 by Marc Lehmann. 202Copyright (C) 2007, 2008 by Marc Lehmann.
187 203
188This library is free software; you can redistribute it and/or modify 204This library is free software; you can redistribute it and/or modify
189it 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,
190at 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.
191 207

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