package File::Spec::Unix;
use strict;
our($VERSION);
$VERSION = '1.4';
use Cwd;
=head1 NAME
File::Spec::Unix - File::Spec for Unix, base for other File::Spec modules
=head1 SYNOPSIS
require File::Spec::Unix; # Done automatically by File::Spec
=head1 DESCRIPTION
Methods for manipulating file specifications. Other File::Spec
modules, such as File::Spec::Mac, inherit from File::Spec::Unix and
override specific methods.
=head1 METHODS
=over 2
=item canonpath()
No physical check on the filesystem, but a logical cleanup of a
path. On UNIX eliminates successive slashes and successive "/.".
$cpath = File::Spec->canonpath( $path ) ;
=cut
sub canonpath {
my ($self,$path) = @_;
# Handle POSIX-style node names beginning with double slash
my $node = '';
if ( $^O =~ m/^(?:qnx|nto)$/ && $path =~ s:^(//[^/]+)(/|\z):/:s ) {
$node = $1;
}
# This used to be
# $path =~ s|/+|/|g unless($^O eq 'cygwin');
# but that made tests 29, 30, 35, 46, and 213 (as of #13272) to fail
# (Mainly because trailing "" directories didn't get stripped).
# Why would cygwin avoid collapsing multiple slashes into one? --jhi
$path =~ s|/+|/|g; # xx////xx -> xx/xx
$path =~ s@(/\.)+(/|\Z(?!\n))@/@g; # xx/././xx -> xx/xx
$path =~ s|^(\./)+||s unless $path eq "./"; # ./xx -> xx
$path =~ s|^/(\.\./)+|/|s; # /../../xx -> xx
$path =~ s|/\Z(?!\n)|| unless $path eq "/"; # xx/ -> xx
return "$node$path";
}
=item catdir()
Concatenate two or more directory names to form a complete path ending
with a directory. But remove the trailing slash from the resulting
string, because it doesn't look good, isn't necessary and confuses
OS2. Of course, if this is the root directory, don't cut off the
trailing slash :-)
=cut
sub catdir {
my $self = shift;
my @args = @_;
foreach (@args) {
# append a slash to each argument unless it has one there
$_ .= "/" if $_ eq '' || substr($_,-1) ne "/";
}
return $self->canonpath(join('', @args));
}
=item catfile
Concatenate one or more directory names and a filename to form a
complete path ending with a filename
=cut
sub catfile {
my $self = shift;
my $file = pop @_;
return $file unless @_;
my $dir = $self->catdir(@_);
$dir .= "/" unless substr($dir,-1) eq "/";
return $dir.$file;
}
=item curdir
Returns a string representation of the current directory. "." on UNIX.
=cut
sub curdir {
return ".";
}
=item devnull
Returns a string representation of the null device. "/dev/null" on UNIX.
=cut
sub devnull {
return "/dev/null";
}
=item rootdir
Returns a string representation of the root directory. "/" on UNIX.
=cut
sub rootdir {
return "/";
}
=item tmpdir
Returns a string representation of the first writable directory
from the following list or "" if none are writable:
$ENV{TMPDIR}
/tmp
Since perl 5.8.0, if running under taint mode, and if $ENV{TMPDIR}
is tainted, it is not used.
=cut
my $tmpdir;
sub tmpdir {
return $tmpdir if defined $tmpdir;
my @dirlist = ($ENV{TMPDIR}, "/tmp");
{
no strict 'refs';
if (${"\cTAINT"}) { # Check for taint mode on perl >= 5.8.0
require Scalar::Util;
shift @dirlist if Scalar::Util::tainted($ENV{TMPDIR});
}
}
foreach (@dirlist) {
next unless defined && -d && -w _;
$tmpdir = $_;
last;
}
$tmpdir = '' unless defined $tmpdir;
return $tmpdir;
}
=item updir
Returns a string representation of the parent directory. ".." on UNIX.
=cut
sub updir {
return "..";
}
=item no_upwards
Given a list of file names, strip out those that refer to a parent
directory. (Does not strip symlinks, only '.', '..', and equivalents.)
=cut
sub no_upwards {
my $self = shift;
return grep(!/^\.{1,2}\Z(?!\n)/s, @_);
}
=item case_tolerant
Returns a true or false value indicating, respectively, that alphabetic
is not or is significant when comparing file specifications.
=cut
sub case_tolerant {
return 0;
}
=item file_name_is_absolute
Takes as argument a path and returns true if it is an absolute path.
This does not consult the local filesystem on Unix, Win32, OS/2 or Mac
OS (Classic). It does consult the working environment for VMS (see
L<File::Spec::VMS/file_name_is_absolute>).
=cut
sub file_name_is_absolute {
my ($self,$file) = @_;
return scalar($file =~ m:^/:s);
}
=item path
Takes no argument, returns the environment variable PATH as an array.
=cut
sub path {
my @path = split(':', $ENV{PATH});
foreach (@path) { $_ = '.' if $_ eq '' }
return @path;
}
=item join
join is the same as catfile.
=cut
sub join {
my $self = shift;
return $self->catfile(@_);
}
=item splitpath
($volume,$directories,$file) = File::Spec->splitpath( $path );
($volume,$directories,$file) = File::Spec->splitpath( $path, $no_file );
Splits a path in to volume, directory, and filename portions. On systems
with no concept of volume, returns undef for volume.
For systems with no syntax differentiating filenames from directories,
assumes that the last file is a path unless $no_file is true or a
trailing separator or /. or /.. is present. On Unix this means that $no_file
true makes this return ( '', $path, '' ).
The directory portion may or may not be returned with a trailing '/'.
The results can be passed to L</catpath()> to get back a path equivalent to
(usually identical to) the original path.
=cut
sub splitpath {
my ($self,$path, $nofile) = @_;
my ($volume,$directory,$file) = ('','','');
if ( $nofile ) {
$directory = $path;
}
else {
$path =~ m|^ ( (?: .* / (?: \.\.?\Z(?!\n) )? )? ) ([^/]*) |xs;
$directory = $1;
$file = $2;
}
return ($volume,$directory,$file);
}
=item splitdir
The opposite of L</catdir()>.
@dirs = File::Spec->splitdir( $directories );
$directories must be only the directory portion of the path on systems
that have the concept of a volume or that have path syntax that differentiates
files from directories.
Unlike just splitting the directories on the separator, empty
directory names (C<''>) can be returned, because these are significant
on some OSs.
On Unix,
File::Spec->splitdir( "/a/b//c/" );
Yields:
( '', 'a', 'b', '', 'c', '' )
=cut
sub splitdir {
my ($self,$directories) = @_ ;
#
# split() likes to forget about trailing null fields, so here we
# check to be sure that there will not be any before handling the
# simple case.
#
if ( $directories !~ m|/\Z(?!\n)| ) {
return split( m|/|, $directories );
}
else {
#
# since there was a trailing separator, add a file name to the end,
# then do the split, then replace it with ''.
#
my( @directories )= split( m|/|, "${directories}dummy" ) ;
$directories[ $#directories ]= '' ;
return @directories ;
}
}
=item catpath()
Takes volume, directory and file portions and returns an entire path. Under
Unix, $volume is ignored, and directory and file are catenated. A '/' is
inserted if need be. On other OSs, $volume is significant.
=cut
sub catpath {
my ($self,$volume,$directory,$file) = @_;
if ( $directory ne '' &&
$file ne '' &&
substr( $directory, -1 ) ne '/' &&
substr( $file, 0, 1 ) ne '/'
) {
$directory .= "/$file" ;
}
else {
$directory .= $file ;
}
return $directory ;
}
=item abs2rel
Takes a destination path and an optional base path returns a relative path
from the base path to the destination path:
$rel_path = File::Spec->abs2rel( $path ) ;
$rel_path = File::Spec->abs2rel( $path, $base ) ;
If $base is not present or '', then L<cwd()|Cwd> is used. If $base is relative,
then it is converted to absolute form using L</rel2abs()>. This means that it
is taken to be relative to L<cwd()|Cwd>.
On systems with the concept of a volume, this assumes that both paths
are on the $destination volume, and ignores the $base volume.
On systems that have a grammar that indicates filenames, this ignores the
$base filename as well. Otherwise all path components are assumed to be
directories.
If $path is relative, it is converted to absolute form using L</rel2abs()>.
This means that it is taken to be relative to L<cwd()|Cwd>.
No checks against the filesystem are made. On VMS, there is
interaction with the working environment, as logicals and
macros are expanded.
Based on code written by Shigio Yamaguchi.
=cut
sub abs2rel {
my($self,$path,$base) = @_;
# Clean up $path
if ( ! $self->file_name_is_absolute( $path ) ) {
$path = $self->rel2abs( $path ) ;
}
else {
$path = $self->canonpath( $path ) ;
}
# Figure out the effective $base and clean it up.
if ( !defined( $base ) || $base eq '' ) {
$base = cwd() ;
}
elsif ( ! $self->file_name_is_absolute( $base ) ) {
$base = $self->rel2abs( $base ) ;
}
else {
$base = $self->canonpath( $base ) ;
}
# Now, remove all leading components that are the same
my @pathchunks = $self->splitdir( $path);
my @basechunks = $self->splitdir( $base);
while (@pathchunks && @basechunks && $pathchunks[0] eq $basechunks[0]) {
shift @pathchunks ;
shift @basechunks ;
}
$path = CORE::join( '/', @pathchunks );
$base = CORE::join( '/', @basechunks );
# $base now contains the directories the resulting relative path
# must ascend out of before it can descend to $path_directory. So,
# replace all names with $parentDir
$base =~ s|[^/]+|..|g ;
# Glue the two together, using a separator if necessary, and preventing an
# empty result.
if ( $path ne '' && $base ne '' ) {
$path = "$base/$path" ;
} else {
$path = "$base$path" ;
}
return $self->canonpath( $path ) ;
}
=item rel2abs()
Converts a relative path to an absolute path.
$abs_path = File::Spec->rel2abs( $path ) ;
$abs_path = File::Spec->rel2abs( $path, $base ) ;
If $base is not present or '', then L<cwd()|Cwd> is used. If $base is relative,
then it is converted to absolute form using L</rel2abs()>. This means that it
is taken to be relative to L<cwd()|Cwd>.
On systems with the concept of a volume, this assumes that both paths
are on the $base volume, and ignores the $path volume.
On systems that have a grammar that indicates filenames, this ignores the
$base filename as well. Otherwise all path components are assumed to be
directories.
If $path is absolute, it is cleaned up and returned using L</canonpath()>.
No checks against the filesystem are made. On VMS, there is
interaction with the working environment, as logicals and
macros are expanded.
Based on code written by Shigio Yamaguchi.
=cut
sub rel2abs {
my ($self,$path,$base ) = @_;
# Clean up $path
if ( ! $self->file_name_is_absolute( $path ) ) {
# Figure out the effective $base and clean it up.
if ( !defined( $base ) || $base eq '' ) {
$base = cwd() ;
}
elsif ( ! $self->file_name_is_absolute( $base ) ) {
$base = $self->rel2abs( $base ) ;
}
else {
$base = $self->canonpath( $base ) ;
}
# Glom them together
$path = $self->catdir( $base, $path ) ;
}
return $self->canonpath( $path ) ;
}
=back
=head1 SEE ALSO
L<File::Spec>
=cut
1;