X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FCwd.pm;h=8b00543e1e9801a51f34472b36cad6f4c3dbfcea;hb=db28185901bfe308f53f975f7d61e927a5f806b5;hp=048842b4ac4cedffa892db532fb1e4f8a492ad41;hpb=2d7a92375815264badaef23c612657cbd4799f31;p=p5sagit%2Fp5-mst-13.2.git diff --git a/lib/Cwd.pm b/lib/Cwd.pm index 048842b..8b00543 100644 --- a/lib/Cwd.pm +++ b/lib/Cwd.pm @@ -1,80 +1,228 @@ package Cwd; -require 5.000; +use 5.006; =head1 NAME -getcwd - get pathname of current working directory +Cwd - get pathname of current working directory =head1 SYNOPSIS use Cwd; - $dir = cwd; + my $dir = getcwd; - use Cwd; - $dir = getcwd; + use Cwd 'abs_path'; + my $abs_path = abs_path($file); - use Cwd; - $dir = fastgetcwd; +=head1 DESCRIPTION - use Cwd 'chdir'; - chdir "/tmp"; - print $ENV{'PWD'}; +This module provides functions for determining the pathname of the +current working directory. It is recommended that getcwd (or another +*cwd() function) be used in I code to ensure portability. -=head1 DESCRIPTION +By default, it exports the functions cwd(), getcwd(), fastcwd(), and +fastgetcwd() into the caller's namespace. + + +=head2 getcwd and friends + +Each of these functions are called without arguments and return the +absolute path of the current working directory. + +=over 4 + +=item getcwd + + my $cwd = getcwd(); + +Returns the current working directory. + +Re-implements the getcwd(3) (or getwd(3)) functions in Perl. + +Taint-safe. + +=item cwd + + my $cwd = cwd(); + +The cwd() is the most natural form for the current architecture. For +most systems it is identical to `pwd` (but without the trailing line +terminator). + +Taint-safe. + +=item fastcwd + + my $cwd = fastcwd(); + +A more dangerous version of getcwd(), but potentially faster. + +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. + +=item fastgetcwd + + my $cwd = fastgetcwd(); + +The fastgetcwd() function is provided as a synonym for cwd(). + +=back + + +=head2 abs_path and friends + +These functions are exported only on request. They each take a single +argument and return the absolute pathname for it. + +=over 4 + +=item abs_path + + my $abs_path = abs_path($file); + +Uses the same algorithm as getcwd(). Symbolic links and relative-path +components ("." and "..") are resolved to return the canonical +pathname, just like realpath(3). + +Taint-safe. + +=item realpath -The getcwd() function re-implements the getcwd(3) (or getwd(3)) functions -in Perl. + my $abs_path = realpath($file); -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. +A synonym for abs_path(). -The cwd() function looks the same as getcwd and fastgetcwd but is -implemented using the most natural and safe form for the current -architecture. For most systems it is identical to `pwd` (but without -the trailing line terminator). +Taint-safe. -It is recommended that cwd (or another *cwd() function) is used in -I code to ensure portability. +=item fast_abs_path -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. + my $abs_path = fast_abs_path($file); + +A more dangerous, but potentially faster version of abs_path. + +This function is B taint-safe : you can't use it in programs +that work under taint mode. + +=back + +=head2 $ENV{PWD} + +If you ask to override your chdir() built-in function, + + use Cwd qw(chdir); + +then your PWD environment variable will be kept up to date. Note that +it will only be kept up to date if all packages which use chdir import +it from Cwd. + + +=head1 NOTES + +=over 4 + +=item * + +Since the path seperators are different on some operating systems ('/' +on Unix, ':' on MacPerl, etc...) we recommend you use the File::Spec +modules wherever portability is a concern. + +=item * + +Actually, on Mac OS, the C, C and C +functions are all aliases for the C function, which, on Mac OS, +calls `pwd`. Likewise, the C function is an alias for +C. + +=back + +=head1 SEE ALSO + +L =cut -## use strict; +use strict; use Carp; -$VERSION = '2.00'; - -require Exporter; -@ISA = qw(Exporter); -@EXPORT = qw(cwd getcwd fastcwd fastgetcwd); -@EXPORT_OK = qw(chdir abs_path fast_abs_path); +our $VERSION = '2.06'; + +use base qw/ Exporter /; +our @EXPORT = qw(cwd getcwd fastcwd fastgetcwd); +our @EXPORT_OK = qw(chdir abs_path fast_abs_path realpath fast_realpath); + +# sys_cwd may keep the builtin command + +# All the functionality of this module may provided by builtins, +# there is no sense to process the rest of the file. +# The best choice may be to have this in BEGIN, but how to return from BEGIN? + +if ($^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; + undef *Cwd::fastcwd; # avoid redefinition warning + XSLoader::load('Cwd'); +}; + + +# Find the pwd command in the expected locations. We assume these +# are safe. This prevents _backtick_pwd() consulting $ENV{PATH} +# so everything works under taint mode. +my $pwd_cmd; +foreach my $try (qw(/bin/pwd /usr/bin/pwd)) { + if( -x $try ) { + $pwd_cmd = $try; + last; + } +} +$pwd_cmd ||= 'pwd'; # The 'natural and safe form' for UNIX (pwd may be setuid root) - sub _backtick_pwd { - my $cwd; - chop($cwd = `pwd`); + local @ENV{qw(PATH IFS CDPATH ENV BASH_ENV)}; + my $cwd = `$pwd_cmd`; + # Belt-and-suspenders in case someone said "undef $/". + local $/ = "\n"; + # `pwd` may fail e.g. if the disk is full + chomp($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(). -*cwd = \&_backtick_pwd unless defined &cwd; +unless(defined &cwd) { + # The pwd command is not available in some chroot(2)'ed environments + if( $^O eq 'MacOS' || (defined $ENV{PATH} && + grep { -x "$_/pwd" } split(':', $ENV{PATH})) ) + { + *cwd = \&_backtick_pwd; + } + else { + *cwd = \&getcwd; + } +} +# set a reasonable (and very safe) default for fastgetcwd, in case it +# isn't redefined later (20001212 rspier) +*fastgetcwd = \&cwd; # By Brandon S. Allbery # @@ -82,66 +230,10 @@ sub _backtick_pwd { sub getcwd { - my($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]) - { - $dir = undef; - } - else - { - do - { - unless (defined ($dir = readdir(PARENT))) - { - warn "readdir($dotdots): $!"; - closedir(PARENT); - return ''; - } - unless (@tst = lstat("$dotdots/$dir")) - { - # warn "lstat($dotdots/$dir): $!"; - # Just because you can't lstat this directory - # doesn't mean you'll never find the right one. - # closedir(PARENT); - # return ''; - } - } - while ($dir eq '.' || $dir eq '..' || $tst[0] != $pst[0] || - $tst[1] != $pst[1]); - } - $cwd = (defined $dir ? "$dir" : "" ) . "/$cwd" ; - closedir(PARENT); - } while (defined $dir); - chop($cwd) unless $cwd eq '/'; # drop the trailing / - $cwd; + abs_path('.'); } - # By John Bazik # # Usage: $cwd = &fastcwd; @@ -149,9 +241,6 @@ sub getcwd # 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. -# List of metachars taken from do_exec() in doio.c -my $quoted_shell_meta = quotemeta('$&*(){}[]";\\|?<>~`'."'\n"); - sub fastcwd { my($odev, $oino, $cdev, $cino, $tdev, $tino); my(@path, $path); @@ -162,7 +251,7 @@ sub fastcwd { for (;;) { my $direntry; ($odev, $oino) = ($cdev, $cino); - chdir('..') || return undef; + CORE::chdir('..') || return undef; ($cdev, $cino) = stat('.'); last if $odev == $cdev && $oino == $cino; opendir(DIR, '.') || return undef; @@ -180,10 +269,11 @@ sub fastcwd { unshift(@path, $direntry); } $path = '/' . join('/', @path); + if ($^O eq 'apollo') { $path = "/".$path; } # At this point $path may be tainted (if tainting) and chdir would fail. - # To be more useful we untaint it then check that we landed where we started. - $path = $1 if $path =~ /^(.*)$/; # untaint - chdir($path) || return undef; + # Untaint it then check that we landed where we started. + $path =~ /^(.*)\z/s # untaint + && CORE::chdir($1) or return undef; ($cdev, $cino) = stat('.'); die "Unstable directory path, current directory changed unexpectedly" if $cdev != $orig_cdev || $cino != $orig_cino; @@ -199,7 +289,7 @@ sub fastcwd { my $chdir_init = 0; sub chdir_init { - if ($ENV{'PWD'} and $^O ne 'os2' and $^O ne 'dos') { + if ($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) { @@ -207,10 +297,12 @@ sub chdir_init { } } else { - $ENV{'PWD'} = cwd(); + my $wd = cwd(); + $wd = Win32::GetFullPathName($wd) if $^O eq 'MSWin32'; + $ENV{'PWD'} = $wd; } # Strip an automounter prefix (where /tmp_mnt/foo/bar == /foo/bar) - if ($ENV{'PWD'} =~ m|(/[^/]+(/[^/]+/[^/]+))(.*)|) { + 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) { @@ -221,13 +313,29 @@ sub chdir_init { } sub chdir { - my $newdir = shift || ''; # allow for no arg (chdir to HOME dir) - $newdir =~ s|///*|/|g; + my $newdir = @_ ? shift : ''; # allow for no arg (chdir to HOME dir) + $newdir =~ s|///*|/|g unless $^O eq 'MSWin32'; chdir_init() unless $chdir_init; + my $newpwd; + if ($^O eq 'MSWin32') { + # get the full path name *before* the chdir() + $newpwd = Win32::GetFullPathName($newdir); + } + return 0 unless CORE::chdir $newdir; - if ($^O eq 'VMS') { return $ENV{'PWD'} = $ENV{'DEFAULT'} } - if ($newdir =~ m#^/#) { + 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'}); @@ -243,13 +351,12 @@ sub chdir { 1; } -# Taken from Cwd.pm It is really getcwd with an optional -# parameter instead of '.' -# -sub abs_path +# In case the XS version doesn't load. +*abs_path = \&_perl_abs_path unless defined &abs_path; +sub _perl_abs_path { - my $start = shift || '.'; + my $start = @_ ? shift : '.'; my($dotdots, $cwd, @pst, @cst, $dir, @tst); unless (@cst = stat( $start )) @@ -276,7 +383,7 @@ sub abs_path } if ($pst[0] == $cst[0] && $pst[1] == $cst[1]) { - $dir = ''; + $dir = undef; } else { @@ -293,27 +400,38 @@ sub abs_path while ($dir eq '.' || $dir eq '..' || $tst[0] != $pst[0] || $tst[1] != $pst[1]); } - $cwd = "$dir/$cwd"; + $cwd = (defined $dir ? "$dir" : "" ) . "/$cwd" ; closedir(PARENT); - } while ($dir); - chop($cwd); # drop the trailing / + } while (defined $dir); + chop($cwd) unless $cwd eq '/'; # drop the trailing / $cwd; } + +# 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(); - my $path = shift || '.'; - chdir($path) || croak "Cannot chdir to $path:$!"; + require File::Spec; + my $path = @_ ? shift : File::Spec->curdir; + CORE::chdir($path) || croak "Cannot chdir to $path: $!"; my $realpath = getcwd(); - chdir($cwd) || croak "Cannot chdir back to $cwd:$!"; + -d $cwd && CORE::chdir($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@genetics.upenn.edu +# 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 @@ -360,8 +478,32 @@ sub _dos_cwd { return $ENV{'PWD'}; } +sub _qnx_cwd { + local $ENV{PATH} = ''; + local $ENV{CDPATH} = ''; + local $ENV{ENV} = ''; + $ENV{'PWD'} = `/usr/bin/fullpath -t`; + chop $ENV{'PWD'}; + return $ENV{'PWD'}; +} + +sub _qnx_abs_path { + local $ENV{PATH} = ''; + local $ENV{CDPATH} = ''; + local $ENV{ENV} = ''; + my $path = @_ ? shift : '.'; + my $realpath=`/usr/bin/fullpath -t $path`; + chop $realpath; + return $realpath; +} + +sub _epoc_cwd { + $ENV{'PWD'} = EPOC::getcwd(); + return $ENV{'PWD'}; +} + { - local $^W = 0; # assignments trigger 'subroutine redefined' warning + no warnings; # assignments trigger 'subroutine redefined' warning if ($^O eq 'VMS') { *cwd = \&_vms_cwd; @@ -378,6 +520,7 @@ sub _dos_cwd { *fastcwd = \&_NT_cwd; *fastgetcwd = \&_NT_cwd; *abs_path = \&fast_abs_path; + *realpath = \&fast_abs_path; } elsif ($^O eq 'os2') { # sys_cwd may keep the builtin command @@ -394,15 +537,34 @@ sub _dos_cwd { *fastcwd = \&_dos_cwd; *abs_path = \&fast_abs_path; } + elsif ($^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";