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Unwrap the del_Xfoo() macros by explicitly noting the arena to free
[perl5.git] / lib / File / Compare.pm
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5f05dabc
PP
1package File::Compare;
2
3b825e41 3use 5.006;
5f05dabc 4use strict;
b395063c 5use warnings;
17f410f9 6our($VERSION, @ISA, @EXPORT, @EXPORT_OK, $Too_Big);
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7
8require Exporter;
9use Carp;
5f05dabc 10
d6a466d7 11$VERSION = '1.1003';
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12@ISA = qw(Exporter);
13@EXPORT = qw(compare);
3724d6f4 14@EXPORT_OK = qw(cmp compare_text);
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15
16$Too_Big = 1024 * 1024 * 2;
17
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18sub compare {
19 croak("Usage: compare( file1, file2 [, buffersize]) ")
20 unless(@_ == 2 || @_ == 3);
21
3724d6f4 22 my ($from,$to,$size) = @_;
167e09eb 23 my $text_mode = defined($size) && (ref($size) eq 'CODE' || $size < 0);
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JD
24
25 my ($fromsize,$closefrom,$closeto);
26 local (*FROM, *TO);
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27
28 croak("from undefined") unless (defined $from);
29 croak("to undefined") unless (defined $to);
30
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G
31 if (ref($from) &&
32 (UNIVERSAL::isa($from,'GLOB') || UNIVERSAL::isa($from,'IO::Handle'))) {
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33 *FROM = *$from;
34 } elsif (ref(\$from) eq 'GLOB') {
35 *FROM = $from;
36 } else {
37 open(FROM,"<$from") or goto fail_open1;
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38 unless ($text_mode) {
39 binmode FROM;
40 $fromsize = -s FROM;
41 }
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42 $closefrom = 1;
43 }
44
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45 if (ref($to) &&
46 (UNIVERSAL::isa($to,'GLOB') || UNIVERSAL::isa($to,'IO::Handle'))) {
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47 *TO = *$to;
48 } elsif (ref(\$to) eq 'GLOB') {
49 *TO = $to;
50 } else {
51 open(TO,"<$to") or goto fail_open2;
3724d6f4 52 binmode TO unless $text_mode;
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53 $closeto = 1;
54 }
55
3724d6f4 56 if (!$text_mode && $closefrom && $closeto) {
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57 # If both are opened files we know they differ if their size differ
58 goto fail_inner if $fromsize != -s TO;
59 }
60
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61 if ($text_mode) {
62 local $/ = "\n";
63 my ($fline,$tline);
64 while (defined($fline = <FROM>)) {
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65 goto fail_inner unless defined($tline = <TO>);
66 if (ref $size) {
67 # $size contains ref to comparison function
68 goto fail_inner if &$size($fline, $tline);
69 } else {
70 goto fail_inner if $fline ne $tline;
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71 }
72 }
73 goto fail_inner if defined($tline = <TO>);
5f05dabc 74 }
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75 else {
76 unless (defined($size) && $size > 0) {
5c99b74d 77 $size = $fromsize || -s TO || 0;
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78 $size = 1024 if $size < 512;
79 $size = $Too_Big if $size > $Too_Big;
80 }
5f05dabc 81
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82 my ($fr,$tr,$fbuf,$tbuf);
83 $fbuf = $tbuf = '';
84 while(defined($fr = read(FROM,$fbuf,$size)) && $fr > 0) {
85 unless (defined($tr = read(TO,$tbuf,$fr)) && $tbuf eq $fbuf) {
86 goto fail_inner;
87 }
5f05dabc 88 }
3724d6f4 89 goto fail_inner if defined($tr = read(TO,$tbuf,$size)) && $tr > 0;
5f05dabc 90 }
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91
92 close(TO) || goto fail_open2 if $closeto;
93 close(FROM) || goto fail_open1 if $closefrom;
94
95 return 0;
96
97 # All of these contortions try to preserve error messages...
98 fail_inner:
99 close(TO) || goto fail_open2 if $closeto;
100 close(FROM) || goto fail_open1 if $closefrom;
101
102 return 1;
103
104 fail_open2:
105 if ($closefrom) {
3724d6f4 106 my $status = $!;
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107 $! = 0;
108 close FROM;
109 $! = $status unless $!;
110 }
111 fail_open1:
112 return -1;
113}
114
17f410f9 115sub cmp;
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116*cmp = \&compare;
117
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118sub compare_text {
119 my ($from,$to,$cmp) = @_;
120 croak("Usage: compare_text( file1, file2 [, cmp-function])")
121 unless @_ == 2 || @_ == 3;
122 croak("Third arg to compare_text() function must be a code reference")
123 if @_ == 3 && ref($cmp) ne 'CODE';
124
125 # Using a negative buffer size puts compare into text_mode too
126 $cmp = -1 unless defined $cmp;
127 compare($from, $to, $cmp);
128}
3724d6f4 129
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1301;
131
132__END__
133
134=head1 NAME
135
136File::Compare - Compare files or filehandles
137
138=head1 SYNOPSIS
139
140 use File::Compare;
141
142 if (compare("file1","file2") == 0) {
143 print "They're equal\n";
144 }
145
146=head1 DESCRIPTION
147
148The File::Compare::compare function compares the contents of two
149sources, each of which can be a file or a file handle. It is exported
150from File::Compare by default.
151
152File::Compare::cmp is a synonym for File::Compare::compare. It is
153exported from File::Compare only by request.
154
3724d6f4 155File::Compare::compare_text does a line by line comparison of the two
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156files. It stops as soon as a difference is detected. compare_text()
157accepts an optional third argument: This must be a CODE reference to
158a line comparison function, which returns 0 when both lines are considered
159equal. For example:
160
161 compare_text($file1, $file2)
162
163is basically equivalent to
164
165 compare_text($file1, $file2, sub {$_[0] ne $_[1]} )
3724d6f4 166
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167=head1 RETURN
168
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169File::Compare::compare and its sibling functions return 0 if the files
170are equal, 1 if the files are unequal, or -1 if an error was encountered.
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171
172=head1 AUTHOR
173
174File::Compare was written by Nick Ing-Simmons.
175Its original documentation was written by Chip Salzenberg.
176
177=cut
178