Initial commit of OpenSPARC T2 architecture model.

[OpenSPARC-T2-SAM] / sam-t2 / devtools / v9 / lib / perl5 / 5.8.8 / File / Compare.pm

package File::Compare;

use 5.006;
use strict;
use warnings;
our($VERSION, @ISA, @EXPORT, @EXPORT_OK, $Too_Big);

require Exporter;
use Carp;

$VERSION = '1.1003';
@ISA = qw(Exporter);
@EXPORT = qw(compare);
@EXPORT_OK = qw(cmp compare_text);

$Too_Big = 1024 * 1024 * 2;

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