| 1 | package Devel::FindRef; |
1 | package Devel::FindRef; |
| 2 | |
2 | |
| 3 | no warnings; # I hate warning nazis |
3 | use common::sense; |
| 4 | use strict; |
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| 5 | |
4 | |
| 6 | use XSLoader; |
5 | use XSLoader; |
| 7 | use Scalar::Util; |
6 | use Scalar::Util; |
| 8 | |
7 | |
| 9 | BEGIN { |
8 | BEGIN { |
| 10 | our $VERSION = '1.31'; |
9 | our $VERSION = '1.422'; |
| 11 | XSLoader::load __PACKAGE__, $VERSION; |
10 | XSLoader::load __PACKAGE__, $VERSION; |
| 12 | } |
11 | } |
| 13 | |
12 | |
| 14 | =head1 NAME |
13 | =head1 NAME |
| 15 | |
14 | |
| … | |
… | |
| 32 | the variables containing them. |
31 | the variables containing them. |
| 33 | |
32 | |
| 34 | For example, for this fragment: |
33 | For example, for this fragment: |
| 35 | |
34 | |
| 36 | package Test; |
35 | package Test; |
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36 | |
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37 | use Devel::FindRef; |
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38 | use Scalar::Util; |
| 37 | |
39 | |
| 38 | our $var = "hi\n"; |
40 | our $var = "hi\n"; |
| 39 | my $x = \$var; |
41 | my $global_my = \$var; |
| 40 | our %hash = (ukukey => \$var); |
42 | our %global_hash = (ukukey => \$var); |
| 41 | our $hash2 = {ukukey2 => \$var}; |
43 | our $global_hashref = { ukukey2 => \$var }; |
| 42 | |
44 | |
| 43 | sub testsub { |
45 | sub testsub { |
| 44 | my $local = $hash2; |
46 | my $testsub_local = $global_hashref; |
| 45 | print Devel::FindRef::track \$var; |
47 | print Devel::FindRef::track \$var; |
| 46 | } |
48 | } |
| 47 | |
49 | |
| 48 | testsub; |
50 | |
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51 | my $closure = sub { |
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52 | my $closure_var = \$_[0]; |
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53 | Scalar::Util::weaken (my $weak_ref = \$var); |
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54 | testsub; |
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55 | }; |
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56 | |
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57 | $closure->($var); |
| 49 | |
58 | |
| 50 | The output is as follows (or similar to this, in case I forget to update |
59 | The output is as follows (or similar to this, in case I forget to update |
| 51 | the manpage after some changes): |
60 | the manpage after some changes): |
| 52 | |
61 | |
| 53 | SCALAR(0x814ece8) is |
62 | SCALAR(0x7cc888) [refcount 6] is |
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63 | +- referenced by REF(0x8abcc8) [refcount 1], which is |
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64 | | the lexical '$closure_var' in CODE(0x8abc50) [refcount 4], which is |
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65 | | +- the closure created at tst:18. |
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66 | | +- referenced by REF(0x7d3c58) [refcount 1], which is |
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67 | | | the lexical '$closure' in CODE(0x7ae530) [refcount 2], which is |
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68 | | | +- the containing scope for CODE(0x8ab430) [refcount 3], which is |
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69 | | | | the global &Test::testsub. |
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70 | | | +- the main body of the program. |
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71 | | +- the lexical '&' in CODE(0x7ae530) [refcount 2], which was seen before. |
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72 | +- referenced by REF(0x7cc7c8) [refcount 1], which is |
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73 | | the lexical '$global_my' in CODE(0x7ae530) [refcount 2], which was seen before. |
| 54 | +- in the global $Test::var. |
74 | +- the global $Test::var. |
| 55 | +- referenced by REF(0x814f9e4), which is |
75 | +- referenced by REF(0x7cc558) [refcount 1], which is |
| 56 | | in the lexical '$x' in CODE(0x814ed78), which is |
76 | | the member 'ukukey2' of HASH(0x7ae140) [refcount 2], which is |
| 57 | | the containing scope for CODE(0x820c4b0), which is |
77 | | +- referenced by REF(0x8abad0) [refcount 1], which is |
| 58 | | in the global &Test::testsub. |
78 | | | the lexical '$testsub_local' in CODE(0x8ab430) [refcount 3], which was seen before. |
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79 | | +- referenced by REF(0x8ab4f0) [refcount 1], which is |
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80 | | the global $Test::global_hashref. |
| 59 | +- referenced by REF(0x814ed6c), which is |
81 | +- referenced by REF(0x7ae518) [refcount 1], which is |
| 60 | | in the member 'ukukey' of HASH(0x81da20c), which is |
82 | | the member 'ukukey' of HASH(0x7d3bb0) [refcount 1], which is |
| 61 | | in the global %Test::hash. |
83 | | the global %Test::global_hash. |
| 62 | +- referenced by REF(0x814ec28), which is |
84 | +- referenced by REF(0x7ae2f0) [refcount 1], which is |
| 63 | | not found anywhere I looked :( |
85 | a temporary on the stack. |
| 64 | +- referenced by REF(0x814eb44), which is |
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| 65 | in the member 'ukukey2' of HASH(0x814f99c), which is |
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| 66 | +- referenced by REF(0x820c450), which is |
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| 67 | | in the lexical '$local' in CODE(0x820c4b0), which was seen before. |
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| 68 | +- referenced by REF(0x820c204), which is |
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| 69 | in the global $Test::hash2. |
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| 70 | |
86 | |
| 71 | It is a bit convoluted to read, but basically it says that the value |
87 | It is a bit convoluted to read, but basically it says that the value |
| 72 | stored in C<$var> can be found: |
88 | stored in C<$var> is referenced by: |
| 73 | |
89 | |
| 74 | =over 4 |
90 | =over 4 |
| 75 | |
91 | |
| 76 | =item - in some variable C<$x> whose origin is not known (I frankly have no |
92 | =item - the lexical C<$closure_var> (0x8abcc8), which is inside an instantiated |
| 77 | idea why, hints accepted). |
93 | closure, which in turn is used quite a bit. |
| 78 | |
94 | |
| 79 | =item - in the hash element with key C<ukukey> in the hash stored in C<%Test::hash>. |
95 | =item - the package-level lexical C<$global_my>. |
| 80 | |
96 | |
| 81 | =item - in the global variable named C<$Test::var>. |
97 | =item - the global package variable named C<$Test::var>. |
| 82 | |
98 | |
| 83 | =item - in the hash element C<ukukey2>, in the hash in the my variable |
99 | =item - the hash element C<ukukey2>, in the hash in the my variable |
| 84 | C<$local> in the sub C<Test::testsub> and also in the hash referenced by |
100 | C<$testsub_local> in the sub C<Test::testsub> and also in the hash |
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101 | C<$referenced by Test::hash2>. |
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102 | |
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103 | =item - the hash element with key C<ukukey> in the hash stored in |
| 85 | C<$Test::hash2>. |
104 | C<%Test::hash>. |
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105 | |
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106 | =item - some anonymous mortalised reference on the stack (which is caused |
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107 | by calling C<track> with the expression C<\$var>, which creates the |
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108 | reference). |
| 86 | |
109 | |
| 87 | =back |
110 | =back |
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111 | |
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112 | And all these account for six reference counts. |
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113 | |
| 88 | |
114 | |
| 89 | =head1 EXPORTS |
115 | =head1 EXPORTS |
| 90 | |
116 | |
| 91 | None. |
117 | None. |
| 92 | |
118 | |
| … | |
… | |
| 124 | |
150 | |
| 125 | if ($depth) { |
151 | if ($depth) { |
| 126 | my (@about) = find $$refref; |
152 | my (@about) = find $$refref; |
| 127 | if (@about) { |
153 | if (@about) { |
| 128 | for my $about (@about) { |
154 | for my $about (@about) { |
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155 | $about->[0] =~ s/([^\x20-\x7e])/sprintf "\\{%02x}", ord $1/ge; |
| 129 | $buf .= "$indent" . (@about > 1 ? "+- " : " ") . $about->[0]; |
156 | $buf .= "$indent" . (@about > 1 ? "+- " : "") . $about->[0]; |
| 130 | if (@$about > 1) { |
157 | if (@$about > 1) { |
| 131 | if ($seen{ref2ptr $about->[1]}++) { |
158 | if ($seen{ref2ptr $about->[1]}++) { |
| 132 | $buf .= " " . (_f $about->[1]) . ", which was seen before.\n"; |
159 | $buf .= " " . (_f $about->[1]) . ", which was seen before.\n"; |
| 133 | } else { |
160 | } else { |
| 134 | $buf .= " " . (_f $about->[1]) . ", which is\n"; |
161 | $buf .= " " . (_f $about->[1]) . ", which is\n"; |
| … | |
… | |
| 145 | $buf .= "$indent not referenced within the search depth.\n"; |
172 | $buf .= "$indent not referenced within the search depth.\n"; |
| 146 | } |
173 | } |
| 147 | }; |
174 | }; |
| 148 | |
175 | |
| 149 | $buf .= (_f $ref) . " is\n"; |
176 | $buf .= (_f $ref) . " is\n"; |
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177 | |
| 150 | $track->(\$ref, $depth || $ENV{PERL_DEVEL_FINDREF_DEPTH} || 10, ""); |
178 | $track->(\$ref, $depth || $ENV{PERL_DEVEL_FINDREF_DEPTH} || 10, ""); |
| 151 | $buf |
179 | $buf |
| 152 | } |
180 | } |
| 153 | |
181 | |
| 154 | =item @references = Devel::FindRef::find $ref |
182 | =item @references = Devel::FindRef::find $ref |
| … | |
… | |
| 164 | =cut |
192 | =cut |
| 165 | |
193 | |
| 166 | sub find($) { |
194 | sub find($) { |
| 167 | my ($about, $excl) = &find_; |
195 | my ($about, $excl) = &find_; |
| 168 | my %excl = map +($_ => undef), @$excl; |
196 | my %excl = map +($_ => undef), @$excl; |
| 169 | grep !exists $excl{ref2ptr $_->[1]}, @$about |
197 | grep !($#$_ && exists $excl{ref2ptr $_->[1]}), @$about |
| 170 | } |
198 | } |
| 171 | |
199 | |
| 172 | =item $ref = Devel::FindRef::ptr2ref $integer |
200 | =item $ref = Devel::FindRef::ptr2ref $integer |
| 173 | |
201 | |
| 174 | Sometimes you know (from debugging output) the address of a perl scalar |
202 | Sometimes you know (from debugging output) the address of a perl value you |
| 175 | you are interested in (e.g. C<HASH(0x176ff70)>). This function can be used |
203 | are interested in (e.g. C<HASH(0x176ff70)>). This function can be used to |
| 176 | to turn the address into a reference to that scalar. It is quite safe to |
204 | turn the address into a reference to that value. It is quite safe to call |
| 177 | call on valid addresses, but extremely dangerous to call on invalid ones. |
205 | on valid addresses, but extremely dangerous to call on invalid ones. I<No |
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206 | checks whatsoever will be done>, so don't use this unless you really know |
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207 | the value is the address of a valid perl value. |
| 178 | |
208 | |
| 179 | # we know that HASH(0x176ff70) exists, so turn it into a hashref: |
209 | # we know that HASH(0x176ff70) exists, so turn it into a hashref: |
| 180 | my $ref_to_hash = Devel::FindRef::ptr2ref 0x176ff70; |
210 | my $ref_to_hash = Devel::FindRef::ptr2ref 0x176ff70; |
| 181 | |
211 | |
| 182 | =item $ref = Devel::FindRef::ref2ptr $reference |
212 | =item $ptr = Devel::FindRef::ref2ptr $reference |
| 183 | |
213 | |
| 184 | The opposite of C<ptr2ref>, above: returns the internal address of the |
214 | The opposite of C<ptr2ref>, above: returns the internal address of the |
| 185 | value pointed to by the passed reference. I<No checks whatsoever will be |
215 | value pointed to by the passed reference. This function is safe to call on |
| 186 | done>, so don't use this. |
216 | anything, and returns the same value taht a normal reference would if used |
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217 | in a numeric context. |
| 187 | |
218 | |
| 188 | =back |
219 | =back |
| 189 | |
220 | |
| 190 | =head1 ENVIRONMENT VARIABLES |
221 | =head1 ENVIRONMENT VARIABLES |
| 191 | |
222 | |
