File Content: Compare.pm package File::Compare; use 5.006; use strict; use warnings; our($VERSION, @ISA, @EXPORT, @EXPORT_OK, $Too_Big); require Exporter; $VERSION = '1.1006'; @ISA = qw(Exporter); @EXPORT = qw(compare); @EXPORT_OK = qw(cmp compare_text); $Too_Big = 1024 * 1024 * 2; sub croak { require Carp; goto &Carp::croak; } sub compare { croak("Usage: compare( file1, file2 [, buffersize]) ") unless(@_ == 2 || @_ == 3); my ($from,$to,$size) = @_; my $text_mode = defined($size) && (ref($size) eq 'CODE' || $size < 0); my ($fromsize,$closefrom,$closeto); local (*FROM, *TO); croak("from undefined") unless (defined $from); croak("to undefined") unless (defined $to); if (ref($from) && (UNIVERSAL::isa($from,'GLOB') || UNIVERSAL::isa($from,'IO::Handle'))) { *FROM = *$from; } elsif (ref(\$from) eq 'GLOB') { *FROM = $from; } else { open(FROM,"<",$from) or goto fail_open1; unless ($text_mode) { binmode FROM; $fromsize = -s FROM; } $closefrom = 1; } if (ref($to) && (UNIVERSAL::isa($to,'GLOB') || UNIVERSAL::isa($to,'IO::Handle'))) { *TO = *$to; } elsif (ref(\$to) eq 'GLOB') { *TO = $to; } else { open(TO,"<",$to) or goto fail_open2; binmode TO unless $text_mode; $closeto = 1; } if (!$text_mode && $closefrom && $closeto) { # If both are opened files we know they differ if their size differ goto fail_inner if $fromsize != -s TO; } if ($text_mode) { local $/ = "\n"; my ($fline,$tline); while (defined($fline = <FROM>)) { goto fail_inner unless defined($tline = <TO>); if (ref $size) { # $size contains ref to comparison function goto fail_inner if &$size($fline, $tline); } else { goto fail_inner if $fline ne $tline; } } goto fail_inner if defined($tline = <TO>); } else { unless (defined($size) && $size > 0) { $size = $fromsize || -s TO || 0; $size = 1024 if $size < 512; $size = $Too_Big if $size > $Too_Big; } my ($fr,$tr,$fbuf,$tbuf); $fbuf = $tbuf = ''; while(defined($fr = read(FROM,$fbuf,$size)) && $fr > 0) { unless (defined($tr = read(TO,$tbuf,$fr)) && $tbuf eq $fbuf) { goto fail_inner; } } goto fail_inner if defined($tr = read(TO,$tbuf,$size)) && $tr > 0; } close(TO) || goto fail_open2 if $closeto; close(FROM) || goto fail_open1 if $closefrom; return 0; # All of these contortions try to preserve error messages... fail_inner: close(TO) || goto fail_open2 if $closeto; close(FROM) || goto fail_open1 if $closefrom; return 1; fail_open2: if ($closefrom) { my $status = $!; $! = 0; close FROM; $! = $status unless $!; } fail_open1: return -1; } sub cmp; *cmp = \&compare; sub compare_text { my ($from,$to,$cmp) = @_; croak("Usage: compare_text( file1, file2 [, cmp-function])") unless @_ == 2 || @_ == 3; croak("Third arg to compare_text() function must be a code reference") if @_ == 3 && ref($cmp) ne 'CODE'; # Using a negative buffer size puts compare into text_mode too $cmp = -1 unless defined $cmp; compare($from, $to, $cmp); } 1; __END__ =head1 NAME File::Compare - Compare files or filehandles =head1 SYNOPSIS use File::Compare; if (compare("file1","file2") == 0) { print "They're equal\n"; } =head1 DESCRIPTION The File::Compare::compare function compares the contents of two sources, each of which can be a file or a file handle. It is exported from File::Compare by default. File::Compare::cmp is a synonym for File::Compare::compare. It is exported from File::Compare only by request. File::Compare::compare_text does a line by line comparison of the two files. It stops as soon as a difference is detected. compare_text() accepts an optional third argument: This must be a CODE reference to a line comparison function, which returns 0 when both lines are considered equal. For example: compare_text($file1, $file2) is basically equivalent to compare_text($file1, $file2, sub {$_[0] ne $_[1]} ) =head1 RETURN File::Compare::compare and its sibling functions return 0 if the files are equal, 1 if the files are unequal, or -1 if an error was encountered. =head1 AUTHOR File::Compare was written by Nick Ing-Simmons. Its original documentation was written by Chip Salzenberg. =cut Submit