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Re: [perl #37716] Re: File::Compare broken for filenames with whitespace
[perl5.git] / lib / File / Compare.pm
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1package File::Compare;
2
3b825e41 3use 5.006;
5f05dabc 4use strict;
b395063c 5use warnings;
17f410f9 6our($VERSION, @ISA, @EXPORT, @EXPORT_OK, $Too_Big);
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7
8require Exporter;
5f05dabc 9
d5693696 10$VERSION = '1.1005';
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11@ISA = qw(Exporter);
12@EXPORT = qw(compare);
3724d6f4 13@EXPORT_OK = qw(cmp compare_text);
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14
15$Too_Big = 1024 * 1024 * 2;
16
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17sub croak {
18 require Carp;
19 goto &Carp::croak;
20}
21
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22sub compare {
23 croak("Usage: compare( file1, file2 [, buffersize]) ")
24 unless(@_ == 2 || @_ == 3);
25
3724d6f4 26 my ($from,$to,$size) = @_;
167e09eb 27 my $text_mode = defined($size) && (ref($size) eq 'CODE' || $size < 0);
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28
29 my ($fromsize,$closefrom,$closeto);
30 local (*FROM, *TO);
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31
32 croak("from undefined") unless (defined $from);
33 croak("to undefined") unless (defined $to);
34
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35 if (ref($from) &&
36 (UNIVERSAL::isa($from,'GLOB') || UNIVERSAL::isa($from,'IO::Handle'))) {
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37 *FROM = *$from;
38 } elsif (ref(\$from) eq 'GLOB') {
39 *FROM = $from;
40 } else {
d5693696 41 open(FROM,"<",$from) or goto fail_open1;
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42 unless ($text_mode) {
43 binmode FROM;
44 $fromsize = -s FROM;
45 }
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46 $closefrom = 1;
47 }
48
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49 if (ref($to) &&
50 (UNIVERSAL::isa($to,'GLOB') || UNIVERSAL::isa($to,'IO::Handle'))) {
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51 *TO = *$to;
52 } elsif (ref(\$to) eq 'GLOB') {
53 *TO = $to;
54 } else {
d5693696 55 open(TO,"<",$to) or goto fail_open2;
3724d6f4 56 binmode TO unless $text_mode;
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57 $closeto = 1;
58 }
59
3724d6f4 60 if (!$text_mode && $closefrom && $closeto) {
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61 # If both are opened files we know they differ if their size differ
62 goto fail_inner if $fromsize != -s TO;
63 }
64
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65 if ($text_mode) {
66 local $/ = "\n";
67 my ($fline,$tline);
68 while (defined($fline = <FROM>)) {
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69 goto fail_inner unless defined($tline = <TO>);
70 if (ref $size) {
71 # $size contains ref to comparison function
72 goto fail_inner if &$size($fline, $tline);
73 } else {
74 goto fail_inner if $fline ne $tline;
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75 }
76 }
77 goto fail_inner if defined($tline = <TO>);
5f05dabc 78 }
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79 else {
80 unless (defined($size) && $size > 0) {
5c99b74d 81 $size = $fromsize || -s TO || 0;
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82 $size = 1024 if $size < 512;
83 $size = $Too_Big if $size > $Too_Big;
84 }
5f05dabc 85
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86 my ($fr,$tr,$fbuf,$tbuf);
87 $fbuf = $tbuf = '';
88 while(defined($fr = read(FROM,$fbuf,$size)) && $fr > 0) {
89 unless (defined($tr = read(TO,$tbuf,$fr)) && $tbuf eq $fbuf) {
90 goto fail_inner;
91 }
5f05dabc 92 }
3724d6f4 93 goto fail_inner if defined($tr = read(TO,$tbuf,$size)) && $tr > 0;
5f05dabc 94 }
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95
96 close(TO) || goto fail_open2 if $closeto;
97 close(FROM) || goto fail_open1 if $closefrom;
98
99 return 0;
100
101 # All of these contortions try to preserve error messages...
102 fail_inner:
103 close(TO) || goto fail_open2 if $closeto;
104 close(FROM) || goto fail_open1 if $closefrom;
105
106 return 1;
107
108 fail_open2:
109 if ($closefrom) {
3724d6f4 110 my $status = $!;
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111 $! = 0;
112 close FROM;
113 $! = $status unless $!;
114 }
115 fail_open1:
116 return -1;
117}
118
17f410f9 119sub cmp;
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120*cmp = \&compare;
121
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122sub compare_text {
123 my ($from,$to,$cmp) = @_;
124 croak("Usage: compare_text( file1, file2 [, cmp-function])")
125 unless @_ == 2 || @_ == 3;
126 croak("Third arg to compare_text() function must be a code reference")
127 if @_ == 3 && ref($cmp) ne 'CODE';
128
129 # Using a negative buffer size puts compare into text_mode too
130 $cmp = -1 unless defined $cmp;
131 compare($from, $to, $cmp);
132}
3724d6f4 133
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1341;
135
136__END__
137
138=head1 NAME
139
140File::Compare - Compare files or filehandles
141
142=head1 SYNOPSIS
143
144 use File::Compare;
145
146 if (compare("file1","file2") == 0) {
147 print "They're equal\n";
148 }
149
150=head1 DESCRIPTION
151
152The File::Compare::compare function compares the contents of two
153sources, each of which can be a file or a file handle. It is exported
154from File::Compare by default.
155
156File::Compare::cmp is a synonym for File::Compare::compare. It is
157exported from File::Compare only by request.
158
3724d6f4 159File::Compare::compare_text does a line by line comparison of the two
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160files. It stops as soon as a difference is detected. compare_text()
161accepts an optional third argument: This must be a CODE reference to
162a line comparison function, which returns 0 when both lines are considered
163equal. For example:
164
165 compare_text($file1, $file2)
166
167is basically equivalent to
168
169 compare_text($file1, $file2, sub {$_[0] ne $_[1]} )
3724d6f4 170
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171=head1 RETURN
172
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173File::Compare::compare and its sibling functions return 0 if the files
174are equal, 1 if the files are unequal, or -1 if an error was encountered.
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175
176=head1 AUTHOR
177
178File::Compare was written by Nick Ing-Simmons.
179Its original documentation was written by Chip Salzenberg.
180
181=cut
182