Commit | Line | Data |
a0d0e21e |
1 | package Cwd; |
2 | require 5.000; |
a0d0e21e |
3 | |
f06db76b |
4 | =head1 NAME |
5 | |
6 | getcwd - get pathname of current working directory |
7 | |
8 | =head1 SYNOPSIS |
9 | |
4633a7c4 |
10 | use Cwd; |
11 | $dir = cwd; |
12 | |
13 | use Cwd; |
14 | $dir = getcwd; |
f06db76b |
15 | |
16 | use Cwd; |
4633a7c4 |
17 | $dir = fastgetcwd; |
f06db76b |
18 | |
19 | use Cwd 'chdir'; |
20 | chdir "/tmp"; |
21 | print $ENV{'PWD'}; |
22 | |
23 | =head1 DESCRIPTION |
24 | |
25 | The getcwd() function re-implements the getcwd(3) (or getwd(3)) functions |
4633a7c4 |
26 | in Perl. |
f06db76b |
27 | |
cb1a09d0 |
28 | The fastcwd() function looks the same as getcwd(), but runs faster. |
fb73857a |
29 | It's also more dangerous because it might conceivably chdir() you out |
30 | of a directory that it can't chdir() you back into. If fastcwd |
31 | encounters a problem it will return undef but will probably leave you |
32 | in a different directory. For a measure of extra security, if |
33 | everything appears to have worked, the fastcwd() function will check |
34 | that it leaves you in the same directory that it started in. If it has |
35 | changed it will C<die> with the message "Unstable directory path, |
36 | current directory changed unexpectedly". That should never happen. |
f06db76b |
37 | |
4633a7c4 |
38 | The cwd() function looks the same as getcwd and fastgetcwd but is |
39 | implemented using the most natural and safe form for the current |
40 | architecture. For most systems it is identical to `pwd` (but without |
fb73857a |
41 | the trailing line terminator). |
42 | |
43 | It is recommended that cwd (or another *cwd() function) is used in |
44 | I<all> code to ensure portability. |
4633a7c4 |
45 | |
46 | If you ask to override your chdir() built-in function, then your PWD |
47 | environment variable will be kept up to date. (See |
55497cff |
48 | L<perlsub/Overriding Builtin Functions>.) Note that it will only be |
1fef88e7 |
49 | kept up to date if all packages which use chdir import it from Cwd. |
4633a7c4 |
50 | |
f06db76b |
51 | =cut |
52 | |
96e4d5b1 |
53 | ## use strict; |
54 | |
55 | use Carp; |
56 | |
07569ed3 |
57 | $VERSION = '2.01'; |
96e4d5b1 |
58 | |
59 | require Exporter; |
a0d0e21e |
60 | @ISA = qw(Exporter); |
e7ae0116 |
61 | @EXPORT = qw(cwd getcwd fastcwd fastgetcwd); |
96e4d5b1 |
62 | @EXPORT_OK = qw(chdir abs_path fast_abs_path); |
a0d0e21e |
63 | |
4633a7c4 |
64 | |
8b88ae92 |
65 | # The 'natural and safe form' for UNIX (pwd may be setuid root) |
96e4d5b1 |
66 | |
8b88ae92 |
67 | sub _backtick_pwd { |
4633a7c4 |
68 | my $cwd; |
69 | chop($cwd = `pwd`); |
70 | $cwd; |
8b88ae92 |
71 | } |
4633a7c4 |
72 | |
73 | # Since some ports may predefine cwd internally (e.g., NT) |
74 | # we take care not to override an existing definition for cwd(). |
75 | |
76 | *cwd = \&_backtick_pwd unless defined &cwd; |
a0d0e21e |
77 | |
748a9306 |
78 | |
a0d0e21e |
79 | # By Brandon S. Allbery |
80 | # |
81 | # Usage: $cwd = getcwd(); |
82 | |
83 | sub getcwd |
84 | { |
07569ed3 |
85 | abs_path('.'); |
a0d0e21e |
86 | } |
87 | |
a0d0e21e |
88 | # By John Bazik |
89 | # |
90 | # Usage: $cwd = &fastcwd; |
91 | # |
92 | # This is a faster version of getcwd. It's also more dangerous because |
93 | # you might chdir out of a directory that you can't chdir back into. |
fb73857a |
94 | |
95 | # List of metachars taken from do_exec() in doio.c |
96 | my $quoted_shell_meta = quotemeta('$&*(){}[]";\\|?<>~`'."'\n"); |
a0d0e21e |
97 | |
98 | sub fastcwd { |
99 | my($odev, $oino, $cdev, $cino, $tdev, $tino); |
100 | my(@path, $path); |
101 | local(*DIR); |
102 | |
fb73857a |
103 | my($orig_cdev, $orig_cino) = stat('.'); |
104 | ($cdev, $cino) = ($orig_cdev, $orig_cino); |
a0d0e21e |
105 | for (;;) { |
40000a8c |
106 | my $direntry; |
a0d0e21e |
107 | ($odev, $oino) = ($cdev, $cino); |
fb73857a |
108 | chdir('..') || return undef; |
a0d0e21e |
109 | ($cdev, $cino) = stat('.'); |
110 | last if $odev == $cdev && $oino == $cino; |
fb73857a |
111 | opendir(DIR, '.') || return undef; |
a0d0e21e |
112 | for (;;) { |
40000a8c |
113 | $direntry = readdir(DIR); |
fb73857a |
114 | last unless defined $direntry; |
40000a8c |
115 | next if $direntry eq '.'; |
116 | next if $direntry eq '..'; |
a0d0e21e |
117 | |
40000a8c |
118 | ($tdev, $tino) = lstat($direntry); |
a0d0e21e |
119 | last unless $tdev != $odev || $tino != $oino; |
120 | } |
121 | closedir(DIR); |
fb73857a |
122 | return undef unless defined $direntry; # should never happen |
40000a8c |
123 | unshift(@path, $direntry); |
a0d0e21e |
124 | } |
fb73857a |
125 | $path = '/' . join('/', @path); |
126 | # At this point $path may be tainted (if tainting) and chdir would fail. |
127 | # To be more useful we untaint it then check that we landed where we started. |
128 | $path = $1 if $path =~ /^(.*)$/; # untaint |
129 | chdir($path) || return undef; |
130 | ($cdev, $cino) = stat('.'); |
131 | die "Unstable directory path, current directory changed unexpectedly" |
132 | if $cdev != $orig_cdev || $cino != $orig_cino; |
a0d0e21e |
133 | $path; |
134 | } |
135 | |
136 | |
4633a7c4 |
137 | # Keeps track of current working directory in PWD environment var |
a0d0e21e |
138 | # Usage: |
139 | # use Cwd 'chdir'; |
140 | # chdir $newdir; |
141 | |
4633a7c4 |
142 | my $chdir_init = 0; |
a0d0e21e |
143 | |
4633a7c4 |
144 | sub chdir_init { |
39e571d4 |
145 | if ($ENV{'PWD'} and $^O ne 'os2' and $^O ne 'dos') { |
a0d0e21e |
146 | my($dd,$di) = stat('.'); |
147 | my($pd,$pi) = stat($ENV{'PWD'}); |
148 | if (!defined $dd or !defined $pd or $di != $pi or $dd != $pd) { |
4633a7c4 |
149 | $ENV{'PWD'} = cwd(); |
a0d0e21e |
150 | } |
151 | } |
152 | else { |
4633a7c4 |
153 | $ENV{'PWD'} = cwd(); |
a0d0e21e |
154 | } |
4633a7c4 |
155 | # Strip an automounter prefix (where /tmp_mnt/foo/bar == /foo/bar) |
a0d0e21e |
156 | if ($ENV{'PWD'} =~ m|(/[^/]+(/[^/]+/[^/]+))(.*)|) { |
157 | my($pd,$pi) = stat($2); |
158 | my($dd,$di) = stat($1); |
159 | if (defined $pd and defined $dd and $di == $pi and $dd == $pd) { |
160 | $ENV{'PWD'}="$2$3"; |
161 | } |
162 | } |
163 | $chdir_init = 1; |
164 | } |
165 | |
166 | sub chdir { |
4633a7c4 |
167 | my $newdir = shift || ''; # allow for no arg (chdir to HOME dir) |
168 | $newdir =~ s|///*|/|g; |
a0d0e21e |
169 | chdir_init() unless $chdir_init; |
4633a7c4 |
170 | return 0 unless CORE::chdir $newdir; |
c6538b72 |
171 | if ($^O eq 'VMS') { return $ENV{'PWD'} = $ENV{'DEFAULT'} } |
748a9306 |
172 | |
a0d0e21e |
173 | if ($newdir =~ m#^/#) { |
174 | $ENV{'PWD'} = $newdir; |
4633a7c4 |
175 | } else { |
176 | my @curdir = split(m#/#,$ENV{'PWD'}); |
177 | @curdir = ('') unless @curdir; |
178 | my $component; |
a0d0e21e |
179 | foreach $component (split(m#/#, $newdir)) { |
180 | next if $component eq '.'; |
181 | pop(@curdir),next if $component eq '..'; |
182 | push(@curdir,$component); |
183 | } |
184 | $ENV{'PWD'} = join('/',@curdir) || '/'; |
185 | } |
4633a7c4 |
186 | 1; |
a0d0e21e |
187 | } |
188 | |
8b88ae92 |
189 | # Taken from Cwd.pm It is really getcwd with an optional |
190 | # parameter instead of '.' |
191 | # |
192 | |
193 | sub abs_path |
194 | { |
07569ed3 |
195 | my $start = @_ ? shift : '.'; |
8b88ae92 |
196 | my($dotdots, $cwd, @pst, @cst, $dir, @tst); |
197 | |
198 | unless (@cst = stat( $start )) |
199 | { |
200 | carp "stat($start): $!"; |
201 | return ''; |
202 | } |
203 | $cwd = ''; |
204 | $dotdots = $start; |
205 | do |
206 | { |
207 | $dotdots .= '/..'; |
208 | @pst = @cst; |
209 | unless (opendir(PARENT, $dotdots)) |
210 | { |
211 | carp "opendir($dotdots): $!"; |
212 | return ''; |
213 | } |
214 | unless (@cst = stat($dotdots)) |
215 | { |
216 | carp "stat($dotdots): $!"; |
217 | closedir(PARENT); |
218 | return ''; |
219 | } |
220 | if ($pst[0] == $cst[0] && $pst[1] == $cst[1]) |
221 | { |
07569ed3 |
222 | $dir = undef; |
8b88ae92 |
223 | } |
224 | else |
225 | { |
226 | do |
227 | { |
228 | unless (defined ($dir = readdir(PARENT))) |
229 | { |
230 | carp "readdir($dotdots): $!"; |
231 | closedir(PARENT); |
232 | return ''; |
233 | } |
234 | $tst[0] = $pst[0]+1 unless (@tst = lstat("$dotdots/$dir")) |
235 | } |
236 | while ($dir eq '.' || $dir eq '..' || $tst[0] != $pst[0] || |
237 | $tst[1] != $pst[1]); |
238 | } |
07569ed3 |
239 | $cwd = (defined $dir ? "$dir" : "" ) . "/$cwd" ; |
8b88ae92 |
240 | closedir(PARENT); |
07569ed3 |
241 | } while (defined $dir); |
242 | chop($cwd) unless $cwd eq '/'; # drop the trailing / |
8b88ae92 |
243 | $cwd; |
244 | } |
245 | |
96e4d5b1 |
246 | sub fast_abs_path { |
247 | my $cwd = getcwd(); |
248 | my $path = shift || '.'; |
249 | chdir($path) || croak "Cannot chdir to $path:$!"; |
250 | my $realpath = getcwd(); |
251 | chdir($cwd) || croak "Cannot chdir back to $cwd:$!"; |
252 | $realpath; |
8b88ae92 |
253 | } |
254 | |
4633a7c4 |
255 | |
256 | # --- PORTING SECTION --- |
257 | |
258 | # VMS: $ENV{'DEFAULT'} points to default directory at all times |
c6538b72 |
259 | # 06-Mar-1996 Charles Bailey bailey@genetics.upenn.edu |
260 | # Note: Use of Cwd::chdir() causes the logical name PWD to be defined |
8b88ae92 |
261 | # in the process logical name table as the default device and directory |
262 | # seen by Perl. This may not be the same as the default device |
4633a7c4 |
263 | # and directory seen by DCL after Perl exits, since the effects |
264 | # the CRTL chdir() function persist only until Perl exits. |
4633a7c4 |
265 | |
266 | sub _vms_cwd { |
96e4d5b1 |
267 | return $ENV{'DEFAULT'}; |
268 | } |
269 | |
270 | sub _vms_abs_path { |
271 | return $ENV{'DEFAULT'} unless @_; |
272 | my $path = VMS::Filespec::pathify($_[0]); |
273 | croak("Invalid path name $_[0]") unless defined $path; |
274 | return VMS::Filespec::rmsexpand($path); |
4633a7c4 |
275 | } |
68dc0745 |
276 | |
4633a7c4 |
277 | sub _os2_cwd { |
278 | $ENV{'PWD'} = `cmd /c cd`; |
279 | chop $ENV{'PWD'}; |
280 | $ENV{'PWD'} =~ s:\\:/:g ; |
281 | return $ENV{'PWD'}; |
282 | } |
283 | |
96e4d5b1 |
284 | sub _win32_cwd { |
2d7a9237 |
285 | $ENV{'PWD'} = Win32::GetCwd(); |
96e4d5b1 |
286 | $ENV{'PWD'} =~ s:\\:/:g ; |
287 | return $ENV{'PWD'}; |
288 | } |
289 | |
290 | *_NT_cwd = \&_win32_cwd if (!defined &_NT_cwd && |
2d7a9237 |
291 | defined &Win32::GetCwd); |
96e4d5b1 |
292 | |
293 | *_NT_cwd = \&_os2_cwd unless defined &_NT_cwd; |
68dc0745 |
294 | |
39e571d4 |
295 | sub _dos_cwd { |
296 | if (!defined &Dos::GetCwd) { |
297 | $ENV{'PWD'} = `command /c cd`; |
298 | chop $ENV{'PWD'}; |
299 | $ENV{'PWD'} =~ s:\\:/:g ; |
300 | } else { |
301 | $ENV{'PWD'} = Dos::GetCwd(); |
302 | } |
55497cff |
303 | return $ENV{'PWD'}; |
304 | } |
305 | |
7fbf1995 |
306 | sub _qnx_cwd { |
307 | $ENV{'PWD'} = `/usr/bin/fullpath -t`; |
308 | chop $ENV{'PWD'}; |
309 | return $ENV{'PWD'}; |
310 | } |
311 | |
312 | sub _qnx_abs_path { |
313 | my $path = shift || '.'; |
314 | my $realpath=`/usr/bin/fullpath -t $path`; |
315 | chop $realpath; |
316 | return $realpath; |
317 | } |
318 | |
ac1ad7f0 |
319 | { |
320 | local $^W = 0; # assignments trigger 'subroutine redefined' warning |
4633a7c4 |
321 | |
ac1ad7f0 |
322 | if ($^O eq 'VMS') { |
96e4d5b1 |
323 | *cwd = \&_vms_cwd; |
324 | *getcwd = \&_vms_cwd; |
325 | *fastcwd = \&_vms_cwd; |
326 | *fastgetcwd = \&_vms_cwd; |
327 | *abs_path = \&_vms_abs_path; |
328 | *fast_abs_path = \&_vms_abs_path; |
ac1ad7f0 |
329 | } |
330 | elsif ($^O eq 'NT' or $^O eq 'MSWin32') { |
331 | # We assume that &_NT_cwd is defined as an XSUB or in the core. |
96e4d5b1 |
332 | *cwd = \&_NT_cwd; |
333 | *getcwd = \&_NT_cwd; |
334 | *fastcwd = \&_NT_cwd; |
335 | *fastgetcwd = \&_NT_cwd; |
336 | *abs_path = \&fast_abs_path; |
ac1ad7f0 |
337 | } |
338 | elsif ($^O eq 'os2') { |
339 | # sys_cwd may keep the builtin command |
96e4d5b1 |
340 | *cwd = defined &sys_cwd ? \&sys_cwd : \&_os2_cwd; |
341 | *getcwd = \&cwd; |
342 | *fastgetcwd = \&cwd; |
343 | *fastcwd = \&cwd; |
344 | *abs_path = \&fast_abs_path; |
ac1ad7f0 |
345 | } |
39e571d4 |
346 | elsif ($^O eq 'dos') { |
347 | *cwd = \&_dos_cwd; |
348 | *getcwd = \&_dos_cwd; |
349 | *fastgetcwd = \&_dos_cwd; |
350 | *fastcwd = \&_dos_cwd; |
96e4d5b1 |
351 | *abs_path = \&fast_abs_path; |
ac1ad7f0 |
352 | } |
7fbf1995 |
353 | elsif ($^O eq 'qnx') { |
354 | *cwd = \&_qnx_cwd; |
355 | *getcwd = \&_qnx_cwd; |
356 | *fastgetcwd = \&_qnx_cwd; |
357 | *fastcwd = \&_qnx_cwd; |
358 | *abs_path = \&_qnx_abs_path; |
359 | *fast_abs_path = \&_qnx_abs_path; |
360 | } |
55497cff |
361 | } |
4633a7c4 |
362 | |
363 | # package main; eval join('',<DATA>) || die $@; # quick test |
364 | |
a0d0e21e |
365 | 1; |
366 | |
4633a7c4 |
367 | __END__ |
368 | BEGIN { import Cwd qw(:DEFAULT chdir); } |
369 | print join("\n", cwd, getcwd, fastcwd, ""); |
370 | chdir('..'); |
371 | print join("\n", cwd, getcwd, fastcwd, ""); |
372 | print "$ENV{PWD}\n"; |