1 | package Devel::FindRef; |
1 | package Devel::FindRef; |
2 | |
2 | |
|
|
3 | no warnings; # I hate warning nazis |
3 | use strict; |
4 | use strict; |
4 | |
5 | |
5 | use XSLoader; |
6 | use XSLoader; |
6 | |
7 | use Scalar::Util; |
7 | |
8 | |
8 | BEGIN { |
9 | BEGIN { |
9 | our $VERSION = '0.1'; |
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 | |
15 | Devel::FindRef - where is that reference to my scalar hiding? |
16 | Devel::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; |
20 | |
21 | |
… | |
… | |
45 | testsub; |
46 | testsub; |
46 | |
47 | |
47 | The output is as follows (or similar to this, in case I forget to update |
48 | The output is as follows (or similar to this, in case I forget to update |
48 | the manpage after some changes): |
49 | the manpage after some changes): |
49 | |
50 | |
50 | SCALAR(0x676fa0) is |
51 | SCALAR(0x814ece8) is |
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52 | +- in the global $Test::var. |
51 | referenced by REF(0x676fb0), which is |
53 | +- referenced by REF(0x814f9e4), which is |
52 | in the lexical '$x' in CODE(0x676370), which is |
54 | | in the lexical '$x' in CODE(0x814ed78), which is |
53 | not found anywhere I looked :( |
55 | | the containing scope for CODE(0x820c4b0), which is |
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56 | | in the global &Test::testsub. |
54 | referenced by REF(0x676360), which is |
57 | +- referenced by REF(0x814ed6c), which is |
55 | in the member 'ukukey' of HASH(0x756660), which is |
58 | | in the member 'ukukey' of HASH(0x81da20c), which is |
56 | in the global %Test::hash. |
59 | | in the global %Test::hash. |
57 | in the global $Test::var. |
|
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58 | referenced by REF(0x6760e0), which is |
60 | +- referenced by REF(0x814ec28), which is |
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61 | | not found anywhere I looked :( |
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62 | +- referenced by REF(0x814eb44), which is |
59 | in the member 'ukukey2' of HASH(0x676f30), which is |
63 | in the member 'ukukey2' of HASH(0x814f99c), which is |
60 | referenced by REF(0x77bcf0), which is |
64 | +- referenced by REF(0x820c450), which is |
61 | in the lexical '$local' in CODE(0x77bcb0), which is |
65 | | in the lexical '$local' in CODE(0x820c4b0), which was seen before. |
62 | in the global &Test::testsub. |
|
|
63 | referenced by REF(0x77bc80), which is |
66 | +- referenced by REF(0x820c204), which is |
64 | in the global $Test::hash2. |
67 | in the global $Test::hash2. |
65 | |
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66 | |
68 | |
67 | It is a bit convoluted to read, but basically it says that the value |
69 | It is a bit convoluted to read, but basically it says that the value |
68 | stored in C<$var> can be found: |
70 | stored in C<$var> can be found: |
69 | |
71 | |
70 | =over 4 |
72 | =over 4 |
… | |
… | |
78 | |
80 | |
79 | =item - in the hash element C<ukukey2>, in the hash in the my variable |
81 | =item - in the hash element C<ukukey2>, in the hash in the my variable |
80 | C<$local> in the sub C<Test::testsub> and also in the hash referenced by |
82 | C<$local> in the sub C<Test::testsub> and also in the hash referenced by |
81 | C<$Test::hash2>. |
83 | C<$Test::hash2>. |
82 | |
84 | |
|
|
85 | =back |
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86 | |
83 | =head1 EXPORTS |
87 | =head1 EXPORTS |
84 | |
88 | |
85 | None. |
89 | None. |
86 | |
90 | |
87 | =head1 FUNCTIONS |
91 | =head1 FUNCTIONS |
… | |
… | |
99 | =cut |
103 | =cut |
100 | |
104 | |
101 | sub find($); |
105 | sub find($); |
102 | |
106 | |
103 | sub track { |
107 | sub track { |
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108 | my ($ref, $depth) = @_; |
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109 | @_ = (); |
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110 | |
104 | my $buf = ""; |
111 | my $buf = ""; |
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112 | my %seen; |
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113 | |
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114 | Scalar::Util::weaken $ref; |
105 | |
115 | |
106 | my $track; $track = sub { |
116 | my $track; $track = sub { |
107 | my (undef, $depth, $indent) = @_; |
117 | my ($refref, $depth, $indent) = @_; |
108 | |
118 | |
109 | if ($depth) { |
119 | if ($depth) { |
110 | my (@about) = find $_[0]; |
120 | my (@about) = find $$refref; |
111 | if (@about) { |
121 | if (@about) { |
112 | for my $about (@about) { |
122 | for my $about (@about) { |
113 | $buf .= (" ") x $indent; |
123 | $buf .= "$indent" . (@about > 1 ? "+- " : " ") . $about->[0]; |
114 | $buf .= $about->[0]; |
|
|
115 | if (@$about > 1) { |
124 | if (@$about > 1) { |
|
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125 | if ($seen{ref2ptr $about->[1]}++) { |
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126 | $buf .= " $about->[1], which was seen before.\n"; |
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127 | } else { |
116 | $buf .= " $about->[1], which is\n"; |
128 | $buf .= " $about->[1], which is\n"; |
117 | $track->($about->[1], $depth - 1, $indent + 1); |
129 | $track->(\$about->[1], $depth - 1, $about == $about[-1] ? "$indent " : "$indent| "); |
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130 | } |
118 | } else { |
131 | } else { |
119 | $buf .= ".\n"; |
132 | $buf .= ".\n"; |
120 | } |
133 | } |
121 | } |
134 | } |
122 | } else { |
135 | } else { |
123 | $buf .= (" ") x $indent; |
|
|
124 | $buf .= "not found anywhere I looked :(\n"; |
136 | $buf .= "$indent not found anywhere I looked :(\n"; |
125 | } |
137 | } |
126 | } else { |
138 | } else { |
127 | $buf .= (" ") x $indent; |
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|
128 | $buf .= "not referenced within the search depth.\n"; |
139 | $buf .= "$indent not referenced within the search depth.\n"; |
129 | } |
140 | } |
130 | }; |
141 | }; |
131 | |
142 | |
132 | $buf .= "$_[0] is\n"; |
143 | $buf .= "$ref is\n"; |
133 | $track->($_[0], $_[1] || 10, 1); |
144 | $track->(\$ref, $depth || $ENV{PERL_DEVEL_FINDREF_DEPTH} || 10, ""); |
134 | $buf |
145 | $buf |
135 | } |
146 | } |
136 | |
147 | |
137 | =item @references = Devel::FindRef::find $ref |
148 | =item @references = Devel::FindRef::find $ref |
138 | |
149 | |
139 | Return arrayrefs that contain [$message, $ref] pairs. The message |
150 | Return arrayrefs that contain [$message, $ref] pairs. The message |
140 | describes what kind of reference was found and the C<$ref> is the |
151 | describes what kind of reference was found and the C<$ref> is the |
141 | reference itself, which cna be omitted if C<find> decided to end the |
152 | reference itself, which can be omitted if C<find> decided to end the |
142 | search. |
153 | search. The returned references are all weak references. |
143 | |
154 | |
144 | The C<track> function uses this to find references to the value you are |
155 | The C<track> function uses this to find references to the value you are |
145 | interested in and recurses on the returned references. |
156 | interested in and recurses on the returned references. |
146 | |
157 | |
147 | =cut |
158 | =cut |
148 | |
159 | |
149 | sub find($) { |
160 | sub find($) { |
150 | my ($about, $excl) = &find_; |
161 | my ($about, $excl) = &find_; |
151 | my %excl = map +($_ => 1), @$excl; |
162 | my %excl = map +($_ => undef), @$excl; |
152 | grep !$excl{$_->[1] + 0}, @$about |
163 | grep !exists $excl{ref2ptr $_->[1]}, @$about |
153 | } |
164 | } |
154 | |
165 | |
155 | =item $ref = Devel::FindRef::ref2ptr $ptr |
166 | =item $ref = Devel::FindRef::ptr2ref $integer |
156 | |
167 | |
157 | Sometimes you know (from debugging output) the address of a perl scalar |
168 | Sometimes you know (from debugging output) the address of a perl scalar |
158 | you are interested in. This function can be used to turn the address into |
169 | you are interested in (e.g. C<HASH(0x176ff70)>). This function can be used |
159 | a reference to that scalar. It is quite safe to call on valid addresses, |
170 | to turn the address into a reference to that scalar. It is quite safe to |
160 | but extremely dangerous to call on invalid ones. |
171 | call on valid addresses, but extremely dangerous to call on invalid ones. |
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172 | |
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173 | # we know that HASH(0x176ff70) exists, so turn it into a hashref: |
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174 | my $ref_to_hash = Devel::FindRef::ptr2ref 0x176ff70; |
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175 | |
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176 | =item $ref = Devel::FindRef::ref2ptr $reference |
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177 | |
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178 | The opposite of C<ptr2ref>, above: returns the internal address of the |
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179 | value pointed to by the passed reference. I<No checks whatsoever will be |
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180 | done>, so don't use this. |
161 | |
181 | |
162 | =back |
182 | =back |
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183 | |
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184 | =head1 ENVIRONMENT VARIABLES |
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185 | |
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186 | You can set the environment variable C<PERL_DEVEL_FINDREF_DEPTH> to an |
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187 | integer to override the default depth in C<track>. If a call explicitly |
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188 | specified a depth it is not overridden. |
163 | |
189 | |
164 | =head1 AUTHOR |
190 | =head1 AUTHOR |
165 | |
191 | |
166 | Marc Lehmann <pcg@goof.com>. |
192 | Marc Lehmann <pcg@goof.com>. |
167 | |
193 | |