X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FCwd.pm;h=3c5c50a35cebfb6d76f79ad8d96f16ecb9ae2176;hb=67597c89125e7e144f9ba60f5b1fe23b951286d8;hp=af1167dfc81f8b871c13fdc7bffa33cfadd8f44f;hpb=f06db76b9e41859439aeadb79feb6c603ee741ff;p=p5sagit%2Fp5-mst-13.2.git diff --git a/lib/Cwd.pm b/lib/Cwd.pm index af1167d..3c5c50a 100644 --- a/lib/Cwd.pm +++ b/lib/Cwd.pm @@ -1,180 +1,193 @@ package Cwd; -require 5.000; -require Exporter; -use Config; +require 5.6.0; =head1 NAME -getcwd - get pathname of current working directory +Cwd - get pathname of current working directory =head1 SYNOPSIS - require Cwd; - $dir = Cwd::getcwd(); + use Cwd; + $dir = cwd; + + use Cwd; + $dir = getcwd; use Cwd; - $dir = getcwd(); + $dir = fastcwd; + + use Cwd; + $dir = fastgetcwd; use Cwd 'chdir'; chdir "/tmp"; print $ENV{'PWD'}; + use Cwd 'abs_path'; # aka realpath() + print abs_path($ENV{'PWD'}); + + use Cwd 'fast_abs_path'; + print fast_abs_path($ENV{'PWD'}); + =head1 DESCRIPTION +This module provides functions for determining the pathname of the +current working directory. By default, it exports the functions +cwd(), getcwd(), fastcwd(), and fastgetcwd() into the caller's +namespace. Each of these functions are called without arguments and +return the absolute path of the current working directory. It is +recommended that cwd (or another *cwd() function) be used in I +code to ensure portability. + +The cwd() is the most natural and safe form for the current +architecture. For most systems it is identical to `pwd` (but without +the trailing line terminator). + The getcwd() function re-implements the getcwd(3) (or getwd(3)) functions -in Perl. If you ask to override your chdir() built-in function, then your -PWD environment variable will be kept up to date. (See -L.) +in Perl. + +The fastcwd() function looks the same as getcwd(), but runs faster. +It's also more dangerous because it might conceivably chdir() you out +of a directory that it can't chdir() you back into. If fastcwd +encounters a problem it will return undef but will probably leave you +in a different directory. For a measure of extra security, if +everything appears to have worked, the fastcwd() function will check +that it leaves you in the same directory that it started in. If it has +changed it will C with the message "Unstable directory path, +current directory changed unexpectedly". That should never happen. + +The fastgetcwd() function is provided as a synonym for cwd(). + +The abs_path() function takes a single argument and returns the +absolute pathname for that argument. It uses the same algorithm as +getcwd(). (Actually, getcwd() is abs_path(".")) Symbolic links and +relative-path components ("." and "..") are resolved to return the +canonical pathname, just like realpath(3). This function is also +callable as realpath(). + +The fast_abs_path() function looks the same as abs_path() but runs +faster and, like fastcwd(), is more dangerous. -The fastgetcwd() function looks the same as getcwd(), but runs faster. -It's also more dangerous because you might conceivably chdir() out of a -directory that you can't chdir() back into. +If you ask to override your chdir() built-in function, then your PWD +environment variable will be kept up to date. (See +L.) Note that it will only be +kept up to date if all packages which use chdir import it from Cwd. + +=head1 NOTES + +=over 4 + +=item * + +On Mac OS (Classic), the path separator is ':', not '/', and the +current directory is denoted as ':', not '.'. To move up the directory +tree, you will use '::' to move up one level, but ':::' and so on to +move up the tree two or more levels (i.e. the equivalent to '../../..' +is '::::'). Generally, you should be careful about specifying relative pathnames. +While a full path always begins with a volume name, a relative pathname +should always begin with a ':'. If specifying a volume name only, a +trailing ':' is required. + +Actually, on Mac OS, the C, C and C +functions are all aliases for the C function, which, on Mac OS, +calls `pwd`. Likewise, the C function is an alias for +C. + +=back =cut -@ISA = qw(Exporter); -@EXPORT = qw(getcwd fastcwd); -@EXPORT_OK = qw(chdir); +use strict; +use Carp; -# VMS: $ENV{'DEFAULT'} points to default directory at all times -# 08-Dec-1994 Charles Bailey bailey@genetics.upenn.edu -# Note: Use of Cwd::getcwd() or Cwd::chdir() (but not Cwd::fastcwd()) -# causes the logical name PWD to be defined in the process -# logical name table as the default device and directory -# seen by Perl. This may not be the same as the default device -# and directory seen by DCL after Perl exits, since the effects -# the CRTL chdir() function persist only until Perl exits. +our $VERSION = '2.05'; -# By Brandon S. Allbery -# -# Usage: $cwd = getcwd(); +use base qw/ Exporter /; +our @EXPORT = qw(cwd getcwd fastcwd fastgetcwd); +our @EXPORT_OK = qw(chdir abs_path fast_abs_path realpath fast_realpath); -sub getcwd -{ - if($Config{'osname'} eq 'VMS') { return $ENV{'PWD'} = $ENV{'DEFAULT'} } - - my($dotdots, $cwd, @pst, @cst, $dir, @tst); - - unless (@cst = stat('.')) - { - warn "stat(.): $!"; - return ''; - } - $cwd = ''; - $dotdots = ''; - do - { - $dotdots .= '/' if $dotdots; - $dotdots .= '..'; - @pst = @cst; - unless (opendir(PARENT, $dotdots)) - { - warn "opendir($dotdots): $!"; - return ''; - } - unless (@cst = stat($dotdots)) - { - warn "stat($dotdots): $!"; - closedir(PARENT); - return ''; - } - if ($pst[0] == $cst[0] && $pst[1] == $cst[1]) - { - $dir = ''; - } - else - { - do - { - unless (defined ($dir = readdir(PARENT))) - { - warn "readdir($dotdots): $!"; - closedir(PARENT); - return ''; - } - unless (@tst = lstat("$dotdots/$dir")) - { - warn "lstat($dotdots/$dir): $!"; - closedir(PARENT); - return ''; - } - } - while ($dir eq '.' || $dir eq '..' || $tst[0] != $pst[0] || - $tst[1] != $pst[1]); - } - $cwd = "$dir/$cwd"; - closedir(PARENT); - } while ($dir); - chop($cwd); # drop the trailing / - $cwd; +# sys_cwd may keep the builtin command + +# All the functionality of this module may provided by builtins, +# there is no sense to process the rest of the file. +# The best choice may be to have this in BEGIN, but how to return from BEGIN? + +if ($^O eq 'os2' && defined &sys_cwd && defined &sys_abspath) { + local $^W = 0; + *cwd = \&sys_cwd; + *getcwd = \&cwd; + *fastgetcwd = \&cwd; + *fastcwd = \&cwd; + *abs_path = \&sys_abspath; + *fast_abs_path = \&abs_path; + *realpath = \&abs_path; + *fast_realpath = \&abs_path; + return 1; } +eval { + require XSLoader; + XSLoader::load('Cwd'); +}; +# The 'natural and safe form' for UNIX (pwd may be setuid root) -# By John Bazik -# -# Usage: $cwd = &fastcwd; -# -# This is a faster version of getcwd. It's also more dangerous because -# you might chdir out of a directory that you can't chdir back into. - -sub fastcwd { - if($Config{'osname'} eq 'VMS') { return $ENV{'DEFAULT'} } - - my($odev, $oino, $cdev, $cino, $tdev, $tino); - my(@path, $path); - local(*DIR); - - ($cdev, $cino) = stat('.'); - for (;;) { - my $direntry; - ($odev, $oino) = ($cdev, $cino); - chdir('..'); - ($cdev, $cino) = stat('.'); - last if $odev == $cdev && $oino == $cino; - opendir(DIR, '.'); - for (;;) { - $direntry = readdir(DIR); - next if $direntry eq '.'; - next if $direntry eq '..'; - - last unless defined $direntry; - ($tdev, $tino) = lstat($direntry); - last unless $tdev != $odev || $tino != $oino; - } - closedir(DIR); - unshift(@path, $direntry); +sub _backtick_pwd { + my $cwd = `pwd`; + # `pwd` may fail e.g. if the disk is full + chomp($cwd) if defined $cwd; + $cwd; +} + +# Since some ports may predefine cwd internally (e.g., NT) +# we take care not to override an existing definition for cwd(). + +unless(defined &cwd) { + # The pwd command is not available in some chroot(2)'ed environments + if($^O eq 'MacOS' || grep { -x "$_/pwd" } split(':', $ENV{PATH})) { + *cwd = \&_backtick_pwd; + } + else { + *cwd = \&getcwd; } - chdir($path = '/' . join('/', @path)); - $path; } +# set a reasonable (and very safe) default for fastgetcwd, in case it +# isn't redefined later (20001212 rspier) +*fastgetcwd = \&cwd; -# keeps track of current working directory in PWD environment var -# -# $RCSfile: pwd.pl,v $$Revision: 4.1 $$Date: 92/08/07 18:24:11 $ -# -# $Log: pwd.pl,v $ +# By Brandon S. Allbery # +# Usage: $cwd = getcwd(); + +sub getcwd +{ + abs_path('.'); +} + +# Keeps track of current working directory in PWD environment var # Usage: # use Cwd 'chdir'; # chdir $newdir; -$chdir_init = 0; +my $chdir_init = 0; -sub chdir_init{ - if ($ENV{'PWD'}) { +sub chdir_init { + if ($ENV{'PWD'} and $^O ne 'os2' and $^O ne 'dos' and $^O ne 'MSWin32') { my($dd,$di) = stat('.'); my($pd,$pi) = stat($ENV{'PWD'}); if (!defined $dd or !defined $pd or $di != $pi or $dd != $pd) { - chop($ENV{'PWD'} = `pwd`); + $ENV{'PWD'} = cwd(); } } else { - chop($ENV{'PWD'} = `pwd`); + my $wd = cwd(); + $wd = Win32::GetFullPathName($wd) if $^O eq 'MSWin32'; + $ENV{'PWD'} = $wd; } - if ($ENV{'PWD'} =~ m|(/[^/]+(/[^/]+/[^/]+))(.*)|) { + # Strip an automounter prefix (where /tmp_mnt/foo/bar == /foo/bar) + if ($^O ne 'MSWin32' and $ENV{'PWD'} =~ m|(/[^/]+(/[^/]+/[^/]+))(.*)|s) { my($pd,$pi) = stat($2); my($dd,$di) = stat($1); if (defined $pd and defined $dd and $di == $pi and $dd == $pd) { @@ -185,17 +198,34 @@ sub chdir_init{ } sub chdir { - my($newdir) = shift; - $newdir =~ s|/{2,}|/|g; + my $newdir = @_ ? shift : ''; # allow for no arg (chdir to HOME dir) + $newdir =~ s|///*|/|g unless $^O eq 'MSWin32'; chdir_init() unless $chdir_init; - return 0 unless (CORE::chdir $newdir); - if ($Config{'osname'} eq 'VMS') { return $ENV{PWD} = $ENV{DEFAULT} } + my $newpwd; + if ($^O eq 'MSWin32') { + # get the full path name *before* the chdir() + $newpwd = Win32::GetFullPathName($newdir); + } - if ($newdir =~ m#^/#) { + return 0 unless CORE::chdir $newdir; + + if ($^O eq 'VMS') { + return $ENV{'PWD'} = $ENV{'DEFAULT'} + } + elsif ($^O eq 'MacOS') { + return $ENV{'PWD'} = cwd(); + } + elsif ($^O eq 'MSWin32') { + $ENV{'PWD'} = $newpwd; + return 1; + } + + if ($newdir =~ m#^/#s) { $ENV{'PWD'} = $newdir; - }else{ - my(@curdir) = split(m#/#,$ENV{'PWD'}); - @curdir = '' unless @curdir; + } else { + my @curdir = split(m#/#,$ENV{'PWD'}); + @curdir = ('') unless @curdir; + my $component; foreach $component (split(m#/#, $newdir)) { next if $component eq '.'; pop(@curdir),next if $component eq '..'; @@ -203,7 +233,166 @@ sub chdir { } $ENV{'PWD'} = join('/',@curdir) || '/'; } + 1; +} + +# added function alias for those of us more +# used to the libc function. --tchrist 27-Jan-00 +*realpath = \&abs_path; + +sub fast_abs_path { + my $cwd = getcwd(); + require File::Spec; + my $path = @_ ? shift : File::Spec->curdir; + CORE::chdir($path) || croak "Cannot chdir to $path:$!"; + my $realpath = getcwd(); + CORE::chdir($cwd) || croak "Cannot chdir back to $cwd:$!"; + $realpath; } +# added function alias to follow principle of least surprise +# based on previous aliasing. --tchrist 27-Jan-00 +*fast_realpath = \&fast_abs_path; + + +# --- PORTING SECTION --- + +# VMS: $ENV{'DEFAULT'} points to default directory at all times +# 06-Mar-1996 Charles Bailey bailey@newman.upenn.edu +# Note: Use of Cwd::chdir() causes the logical name PWD to be defined +# in the process logical name table as the default device and directory +# seen by Perl. This may not be the same as the default device +# and directory seen by DCL after Perl exits, since the effects +# the CRTL chdir() function persist only until Perl exits. + +sub _vms_cwd { + return $ENV{'DEFAULT'}; +} + +sub _vms_abs_path { + return $ENV{'DEFAULT'} unless @_; + my $path = VMS::Filespec::pathify($_[0]); + croak("Invalid path name $_[0]") unless defined $path; + return VMS::Filespec::rmsexpand($path); +} + +sub _os2_cwd { + $ENV{'PWD'} = `cmd /c cd`; + chop $ENV{'PWD'}; + $ENV{'PWD'} =~ s:\\:/:g ; + return $ENV{'PWD'}; +} + +sub _win32_cwd { + $ENV{'PWD'} = Win32::GetCwd(); + $ENV{'PWD'} =~ s:\\:/:g ; + return $ENV{'PWD'}; +} + +*_NT_cwd = \&_win32_cwd if (!defined &_NT_cwd && + defined &Win32::GetCwd); + +*_NT_cwd = \&_os2_cwd unless defined &_NT_cwd; + +sub _dos_cwd { + if (!defined &Dos::GetCwd) { + $ENV{'PWD'} = `command /c cd`; + chop $ENV{'PWD'}; + $ENV{'PWD'} =~ s:\\:/:g ; + } else { + $ENV{'PWD'} = Dos::GetCwd(); + } + return $ENV{'PWD'}; +} + +sub _qnx_cwd { + $ENV{'PWD'} = `/usr/bin/fullpath -t`; + chop $ENV{'PWD'}; + return $ENV{'PWD'}; +} + +sub _qnx_abs_path { + my $path = @_ ? shift : '.'; + my $realpath=`/usr/bin/fullpath -t $path`; + chop $realpath; + return $realpath; +} + +sub _epoc_cwd { + $ENV{'PWD'} = EPOC::getcwd(); + return $ENV{'PWD'}; +} + +{ + no warnings; # assignments trigger 'subroutine redefined' warning + + if ($^O eq 'VMS') { + *cwd = \&_vms_cwd; + *getcwd = \&_vms_cwd; + *fastcwd = \&_vms_cwd; + *fastgetcwd = \&_vms_cwd; + *abs_path = \&_vms_abs_path; + *fast_abs_path = \&_vms_abs_path; + } + elsif ($^O eq 'NT' or $^O eq 'MSWin32') { + # We assume that &_NT_cwd is defined as an XSUB or in the core. + *cwd = \&_NT_cwd; + *getcwd = \&_NT_cwd; + *fastcwd = \&_NT_cwd; + *fastgetcwd = \&_NT_cwd; + *abs_path = \&fast_abs_path; + } + elsif ($^O eq 'os2') { + # sys_cwd may keep the builtin command + *cwd = defined &sys_cwd ? \&sys_cwd : \&_os2_cwd; + *getcwd = \&cwd; + *fastgetcwd = \&cwd; + *fastcwd = \&cwd; + *abs_path = \&fast_abs_path; + } + elsif ($^O eq 'dos') { + *cwd = \&_dos_cwd; + *getcwd = \&_dos_cwd; + *fastgetcwd = \&_dos_cwd; + *fastcwd = \&_dos_cwd; + *abs_path = \&fast_abs_path; + } + elsif ($^O =~ m/^(?:qnx|nto)$/ ) { + *cwd = \&_qnx_cwd; + *getcwd = \&_qnx_cwd; + *fastgetcwd = \&_qnx_cwd; + *fastcwd = \&_qnx_cwd; + *abs_path = \&_qnx_abs_path; + *fast_abs_path = \&_qnx_abs_path; + } + elsif ($^O eq 'cygwin') { + *getcwd = \&cwd; + *fastgetcwd = \&cwd; + *fastcwd = \&cwd; + *abs_path = \&fast_abs_path; + } + elsif ($^O eq 'epoc') { + *cwd = \&_epoc_cwd; + *getcwd = \&_epoc_cwd; + *fastgetcwd = \&_epoc_cwd; + *fastcwd = \&_epoc_cwd; + *abs_path = \&fast_abs_path; + } + elsif ($^O eq 'MacOS') { + *getcwd = \&cwd; + *fastgetcwd = \&cwd; + *fastcwd = \&cwd; + *abs_path = \&fast_abs_path; + } +} + +# package main; eval join('',) || die $@; # quick test + 1; +__END__ +BEGIN { import Cwd qw(:DEFAULT chdir); } +print join("\n", cwd, getcwd, fastcwd, ""); +chdir('..'); +print join("\n", cwd, getcwd, fastcwd, ""); +print "$ENV{PWD}\n";