copy.pm

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# File/Copy.pm. Written in 1994 by Aaron Sherman <[e-mail]>. This
# source code has been placed in the public domain by the author.
# Please be kind and preserve the documentation.
#
# Additions copyright 1996 by Charles Bailey.  Permission is granted
# to distribute the revised code under the same terms as Perl itself.

package File::Copy;

use 5.006;
use strict;
use warnings;
use File::Spec;
use Config;
our(@ISA, @EXPORT, @EXPORT_OK, $VERSION, $Too_Big, $Syscopy_is_copy);
sub copy;
sub syscopy;
sub cp;
sub mv;

# Note that this module implements only *part* of the API defined by
# the File/Copy.pm module of the File-Tools-2.0 package.  However, that
# package has not yet been updated to work with Perl 5.004, and so it
# would be a Bad Thing for the CPAN module to grab it and replace this
# module.  Therefore, we set this module's version higher than 2.0.
$VERSION = '2.11';

require Exporter;
@ISA = qw(Exporter);
@EXPORT = qw(copy move);
@EXPORT_OK = qw(cp mv);

$Too_Big = 1024 * 1024 * 2;

sub croak {
    require Carp;
    goto &Carp::croak;
}

sub carp {
    require Carp;
    goto &Carp::carp;
}

my $macfiles;
if ($^O eq 'MacOS') {
	$macfiles = eval { require Mac::MoreFiles };
	warn 'Mac::MoreFiles could not be loaded; using non-native syscopy'
		if $@ && $^W;
}

sub _catname {
    my($from, $to) = @_;
    if (not defined &basename) {
	require File::Basename;
	import  File::Basename 'basename';
    }

    if ($^O eq 'MacOS') {
	# a partial dir name that's valid only in the cwd (e.g. 'tmp')
	$to = ':' . $to if $to !~ /:/;
    }

    return File::Spec->catfile($to, basename($from));
}

# _eq($from, $to) tells whether $from and $to are identical
# works for strings and references
sub _eq {
    return $_[0] == $_[1] if ref $_[0] && ref $_[1];
    return $_[0] eq $_[1] if !ref $_[0] && !ref $_[1];
    return "";
}

sub copy {
    croak("Usage: copy(FROM, TO [, BUFFERSIZE]) ")
      unless(@_ == 2 || @_ == 3);

    my $from = shift;
    my $to = shift;

    my $from_a_handle = (ref($from)
			 ? (ref($from) eq 'GLOB'
			    || UNIVERSAL::isa($from, 'GLOB')
                            || UNIVERSAL::isa($from, 'IO::Handle'))
			 : (ref(\$from) eq 'GLOB'));
    my $to_a_handle =   (ref($to)
			 ? (ref($to) eq 'GLOB'
			    || UNIVERSAL::isa($to, 'GLOB')
                            || UNIVERSAL::isa($to, 'IO::Handle'))
			 : (ref(\$to) eq 'GLOB'));

    if (_eq($from, $to)) { # works for references, too
	carp("'$from' and '$to' are identical (not copied)");
        # The "copy" was a success as the source and destination contain
        # the same data.
        return 1;
    }

    if ((($Config{d_symlink} && $Config{d_readlink}) || $Config{d_link}) &&
	!($^O eq 'MSWin32' || $^O eq 'os2')) {
	my @fs = stat($from);
	if (@fs) {
	    my @ts = stat($to);
	    if (@ts && $fs[0] == $ts[0] && $fs[1] == $ts[1]) {
		carp("'$from' and '$to' are identical (not copied)");
                return 0;
	    }
	}
    }

    if (!$from_a_handle && !$to_a_handle && -d $to && ! -d $from) {
	$to = _catname($from, $to);
    }

    if (defined &syscopy && !$Syscopy_is_copy
	&& !$to_a_handle
	&& !($from_a_handle && $^O eq 'os2' )	# OS/2 cannot handle handles
	&& !($from_a_handle && $^O eq 'mpeix')	# and neither can MPE/iX.
	&& !($from_a_handle && $^O eq 'MSWin32')
	&& !($from_a_handle && $^O eq 'MacOS')
	&& !($from_a_handle && $^O eq 'NetWare')
       )
    {
	my $copy_to = $to;

        if ($^O eq 'VMS' && -e $from) {

            if (! -d $to && ! -d $from) {

                # VMS has sticky defaults on extensions, which means that
                # if there is a null extension on the destination file, it
                # will inherit the extension of the source file
                # So add a '.' for a null extension.

                $copy_to = VMS::Filespec::vmsify($to);
                my ($vol, $dirs, $file) = File::Spec->splitpath($copy_to);
                $file = $file . '.' unless ($file =~ /(?<!\^)\./);
                $copy_to = File::Spec->catpath($vol, $dirs, $file);

                # Get rid of the old versions to be like UNIX
                1 while unlink $copy_to;
            }
        }

        return syscopy($from, $copy_to);
    }

    my $closefrom = 0;
    my $closeto = 0;
    my ($size, $status, $r, $buf);
    local($\) = '';

    my $from_h;
    if ($from_a_handle) {
       $from_h = $from;
    } else {
	$from = _protect($from) if $from =~ /^\s/s;
       $from_h = \do { local *FH };
       open($from_h, "< $from\0") or goto fail_open1;
       binmode $from_h or die "($!,$^E)";
	$closefrom = 1;
    }

    my $to_h;
    if ($to_a_handle) {
       $to_h = $to;
    } else {
	$to = _protect($to) if $to =~ /^\s/s;
       $to_h = \do { local *FH };
       open($to_h,"> $to\0") or goto fail_open2;
       binmode $to_h or die "($!,$^E)";
	$closeto = 1;
    }

    if (@_) {
	$size = shift(@_) + 0;
	croak("Bad buffer size for copy: $size\n") unless ($size > 0);
    } else {
	$size = tied(*$from_h) ? 0 : -s $from_h || 0;
	$size = 1024 if ($size < 512);
	$size = $Too_Big if ($size > $Too_Big);
    }

    $! = 0;
    for (;;) {
	my ($r, $w, $t);
       defined($r = sysread($from_h, $buf, $size))
	    or goto fail_inner;
	last unless $r;
	for ($w = 0; $w < $r; $w += $t) {
           $t = syswrite($to_h, $buf, $r - $w, $w)
		or goto fail_inner;
	}
    }

    close($to_h) || goto fail_open2 if $closeto;
    close($from_h) || goto fail_open1 if $closefrom;

    # Use this idiom to avoid uninitialized value warning.
    return 1;

    # All of these contortions try to preserve error messages...
  fail_inner:
    if ($closeto) {
	$status = $!;
	$! = 0;
       close $to_h;
	$! = $status unless $!;
    }
  fail_open2:
    if ($closefrom) {
	$status = $!;
	$! = 0;
       close $from_h;
	$! = $status unless $!;
    }
  fail_open1:
    return 0;
}

sub move {
    croak("Usage: move(FROM, TO) ") unless @_ == 2;

    my($from,$to) = @_;

    my($fromsz,$tosz1,$tomt1,$tosz2,$tomt2,$sts,$ossts);

    if (-d $to && ! -d $from) {
	$to = _catname($from, $to);
    }

    ($tosz1,$tomt1) = (stat($to))[7,9];
    $fromsz = -s $from;
    if ($^O eq 'os2' and defined $tosz1 and defined $fromsz) {
      # will not rename with overwrite
      unlink $to;
    }

    my $rename_to = $to;
    if (-$^O eq 'VMS' && -e $from) {

        if (! -d $to && ! -d $from) {
            # VMS has sticky defaults on extensions, which means that
            # if there is a null extension on the destination file, it
            # will inherit the extension of the source file
            # So add a '.' for a null extension.

            $rename_to = VMS::Filespec::vmsify($to);
            my ($vol, $dirs, $file) = File::Spec->splitpath($rename_to);
            $file = $file . '.' unless ($file =~ /(?<!\^)\./);
            $rename_to = File::Spec->catpath($vol, $dirs, $file);

            # Get rid of the old versions to be like UNIX
            1 while unlink $rename_to;
        }
    }

    return 1 if rename $from, $rename_to;

    # Did rename return an error even though it succeeded, because $to