Commit | Line | Data |
---|---|---|
36477c24 | 1 | package File::stat; |
3b825e41 RK |
2 | use 5.006; |
3 | ||
36477c24 | 4 | use strict; |
b395063c | 5 | use warnings; |
b7c4737f | 6 | use warnings::register; |
448e77d7 | 7 | use Carp; |
36477c24 | 8 | |
b7c4737f BM |
9 | BEGIN { *warnif = \&warnings::warnif } |
10 | ||
17f410f9 GS |
11 | our(@EXPORT, @EXPORT_OK, %EXPORT_TAGS); |
12 | ||
4c77591b | 13 | our $VERSION = '1.07'; |
b75c8c73 | 14 | |
4f9e7902 | 15 | my @fields; |
36477c24 | 16 | BEGIN { |
17 | use Exporter (); | |
36477c24 | 18 | @EXPORT = qw(stat lstat); |
4f9e7902 | 19 | @fields = qw( $st_dev $st_ino $st_mode |
36477c24 | 20 | $st_nlink $st_uid $st_gid |
21 | $st_rdev $st_size | |
22 | $st_atime $st_mtime $st_ctime | |
23 | $st_blksize $st_blocks | |
24 | ); | |
4f9e7902 BM |
25 | @EXPORT_OK = ( @fields, "stat_cando" ); |
26 | %EXPORT_TAGS = ( FIELDS => [ @fields, @EXPORT ] ); | |
36477c24 | 27 | } |
4f9e7902 | 28 | use vars @fields; |
36477c24 | 29 | |
448e77d7 BM |
30 | use Fcntl qw(S_IRUSR S_IWUSR S_IXUSR); |
31 | ||
32 | BEGIN { | |
33 | # These constants will croak on use if the platform doesn't define | |
34 | # them. It's important to avoid inflicting that on the user. | |
35 | no strict 'refs'; | |
36 | for (qw(suid sgid svtx)) { | |
37 | my $val = eval { &{"Fcntl::S_I\U$_"} }; | |
38 | *{"_$_"} = defined $val ? sub { $_[0] & $val ? 1 : "" } : sub { "" }; | |
39 | } | |
2b9f61bf | 40 | for (qw(SOCK CHR BLK REG DIR LNK)) { |
448e77d7 BM |
41 | *{"S_IS$_"} = defined eval { &{"Fcntl::S_IF$_"} } |
42 | ? \&{"Fcntl::S_IS$_"} : sub { "" }; | |
43 | } | |
2b9f61bf TC |
44 | # FIFO flag and macro don't quite follow the S_IF/S_IS pattern above |
45 | # RT #111638 | |
46 | *{"S_ISFIFO"} = defined &Fcntl::S_IFIFO | |
47 | ? \&Fcntl::S_ISFIFO : sub { "" }; | |
448e77d7 BM |
48 | } |
49 | ||
50 | # from doio.c | |
51 | sub _ingroup { | |
448e77d7 BM |
52 | my ($gid, $eff) = @_; |
53 | ||
54 | # I am assuming that since VMS doesn't have getgroups(2), $) will | |
55 | # always only contain a single entry. | |
56 | $^O eq "VMS" and return $_[0] == $); | |
57 | ||
58 | my ($egid, @supp) = split " ", $); | |
59 | my ($rgid) = split " ", $(; | |
60 | ||
61 | $gid == ($eff ? $egid : $rgid) and return 1; | |
62 | grep $gid == $_, @supp and return 1; | |
63 | ||
64 | return ""; | |
65 | } | |
66 | ||
67 | # VMS uses the Unix version of the routine, even though this is very | |
68 | # suboptimal. VMS has a permissions structure that doesn't really fit | |
69 | # into struct stat, and unlike on Win32 the normal -X operators respect | |
70 | # that, but unfortunately by the time we get here we've already lost the | |
71 | # information we need. It looks to me as though if we were to preserve | |
72 | # the st_devnam entry of vmsish.h's fake struct stat (which actually | |
73 | # holds the filename) it might be possible to do this right, but both | |
74 | # getting that value out of the struct (perl's stat doesn't return it) | |
75 | # and interpreting it later would require this module to have an XS | |
76 | # component (at which point we might as well just call Perl_cando and | |
77 | # have done with it). | |
78 | ||
79 | if (grep $^O eq $_, qw/os2 MSWin32 dos/) { | |
80 | ||
81 | # from doio.c | |
0e985b6b | 82 | *cando = sub { ($_[0][2] & $_[1]) ? 1 : "" }; |
448e77d7 BM |
83 | } |
84 | else { | |
85 | ||
86 | # from doio.c | |
87 | *cando = sub { | |
88 | my ($s, $mode, $eff) = @_; | |
89 | my $uid = $eff ? $> : $<; | |
4f9e7902 BM |
90 | my ($stmode, $stuid, $stgid) = @$s[2,4,5]; |
91 | ||
448e77d7 BM |
92 | # This code basically assumes that the rwx bits of the mode are |
93 | # the 0777 bits, but so does Perl_cando. | |
4c77591b NC |
94 | |
95 | if ($uid == 0 && $^O ne "VMS") { | |
96 | # If we're root on unix | |
97 | # not testing for executable status => all file tests are true | |
98 | return 1 if !($mode & 0111); | |
99 | # testing for executable status => | |
100 | # for a file, any x bit will do | |
101 | # for a directory, always true | |
102 | return 1 if $stmode & 0111 || S_ISDIR($stmode); | |
103 | return ""; | |
104 | } | |
105 | ||
4f9e7902 BM |
106 | if ($stuid == $uid) { |
107 | $stmode & $mode and return 1; | |
448e77d7 | 108 | } |
4f9e7902 BM |
109 | elsif (_ingroup($stgid, $eff)) { |
110 | $stmode & ($mode >> 3) and return 1; | |
448e77d7 BM |
111 | } |
112 | else { | |
4f9e7902 | 113 | $stmode & ($mode >> 6) and return 1; |
448e77d7 BM |
114 | } |
115 | return ""; | |
116 | }; | |
117 | } | |
118 | ||
4f9e7902 BM |
119 | # alias for those who don't like objects |
120 | *stat_cando = \&cando; | |
121 | ||
448e77d7 BM |
122 | my %op = ( |
123 | r => sub { cando($_[0], S_IRUSR, 1) }, | |
124 | w => sub { cando($_[0], S_IWUSR, 1) }, | |
125 | x => sub { cando($_[0], S_IXUSR, 1) }, | |
4f9e7902 | 126 | o => sub { $_[0][4] == $> }, |
448e77d7 BM |
127 | |
128 | R => sub { cando($_[0], S_IRUSR, 0) }, | |
129 | W => sub { cando($_[0], S_IWUSR, 0) }, | |
130 | X => sub { cando($_[0], S_IXUSR, 0) }, | |
4f9e7902 | 131 | O => sub { $_[0][4] == $< }, |
448e77d7 BM |
132 | |
133 | e => sub { 1 }, | |
4f9e7902 BM |
134 | z => sub { $_[0][7] == 0 }, |
135 | s => sub { $_[0][7] }, | |
136 | ||
137 | f => sub { S_ISREG ($_[0][2]) }, | |
138 | d => sub { S_ISDIR ($_[0][2]) }, | |
139 | l => sub { S_ISLNK ($_[0][2]) }, | |
140 | p => sub { S_ISFIFO($_[0][2]) }, | |
141 | S => sub { S_ISSOCK($_[0][2]) }, | |
142 | b => sub { S_ISBLK ($_[0][2]) }, | |
143 | c => sub { S_ISCHR ($_[0][2]) }, | |
144 | ||
145 | u => sub { _suid($_[0][2]) }, | |
146 | g => sub { _sgid($_[0][2]) }, | |
147 | k => sub { _svtx($_[0][2]) }, | |
148 | ||
149 | M => sub { ($^T - $_[0][9] ) / 86400 }, | |
150 | C => sub { ($^T - $_[0][10]) / 86400 }, | |
151 | A => sub { ($^T - $_[0][8] ) / 86400 }, | |
448e77d7 BM |
152 | ); |
153 | ||
b7c4737f BM |
154 | use constant HINT_FILETEST_ACCESS => 0x00400000; |
155 | ||
4f9e7902 | 156 | # we need fallback=>1 or stringifying breaks |
448e77d7 BM |
157 | use overload |
158 | fallback => 1, | |
159 | -X => sub { | |
160 | my ($s, $op) = @_; | |
b7c4737f | 161 | |
330e7bfa | 162 | if (index("rwxRWX", $op) >= 0) { |
b7c4737f BM |
163 | (caller 0)[8] & HINT_FILETEST_ACCESS |
164 | and warnif("File::stat ignores use filetest 'access'"); | |
165 | ||
166 | $^O eq "VMS" and warnif("File::stat ignores VMS ACLs"); | |
167 | ||
168 | # It would be nice to have a warning about using -l on a | |
169 | # non-lstat, but that would require an extra member in the | |
170 | # object. | |
171 | } | |
4f9e7902 | 172 | |
448e77d7 BM |
173 | if ($op{$op}) { |
174 | return $op{$op}->($_[0]); | |
175 | } | |
176 | else { | |
177 | croak "-$op is not implemented on a File::stat object"; | |
178 | } | |
179 | }; | |
180 | ||
8cc95fdb | 181 | # Class::Struct forbids use of @ISA |
182 | sub import { goto &Exporter::import } | |
183 | ||
ee28235b | 184 | use Class::Struct qw(struct); |
36477c24 | 185 | struct 'File::stat' => [ |
186 | map { $_ => '$' } qw{ | |
187 | dev ino mode nlink uid gid rdev size | |
188 | atime mtime ctime blksize blocks | |
189 | } | |
190 | ]; | |
191 | ||
192 | sub populate (@) { | |
193 | return unless @_; | |
194 | my $stob = new(); | |
195 | @$stob = ( | |
196 | $st_dev, $st_ino, $st_mode, $st_nlink, $st_uid, $st_gid, $st_rdev, | |
197 | $st_size, $st_atime, $st_mtime, $st_ctime, $st_blksize, $st_blocks ) | |
198 | = @_; | |
199 | return $stob; | |
200 | } | |
201 | ||
14d597e2 | 202 | sub lstat ($) { populate(CORE::lstat(shift)) } |
36477c24 | 203 | |
204 | sub stat ($) { | |
205 | my $arg = shift; | |
206 | my $st = populate(CORE::stat $arg); | |
448e77d7 | 207 | return $st if defined $st; |
2f173a71 | 208 | my $fh; |
209 | { | |
210 | local $!; | |
211 | no strict 'refs'; | |
212 | require Symbol; | |
83716b1e | 213 | $fh = \*{ Symbol::qualify( $arg, caller() )}; |
2f173a71 | 214 | return unless defined fileno $fh; |
215 | } | |
216 | return populate(CORE::stat $fh); | |
36477c24 | 217 | } |
218 | ||
219 | 1; | |
220 | __END__ | |
221 | ||
222 | =head1 NAME | |
223 | ||
2ae324a7 | 224 | File::stat - by-name interface to Perl's built-in stat() functions |
36477c24 | 225 | |
226 | =head1 SYNOPSIS | |
227 | ||
228 | use File::stat; | |
229 | $st = stat($file) or die "No $file: $!"; | |
230 | if ( ($st->mode & 0111) && $st->nlink > 1) ) { | |
231 | print "$file is executable with lotsa links\n"; | |
232 | } | |
233 | ||
6cf0ee86 BM |
234 | if ( -x $st ) { |
235 | print "$file is executable\n"; | |
236 | } | |
237 | ||
238 | use Fcntl "S_IRUSR"; | |
239 | if ( $st->cando(S_IRUSR, 1) ) { | |
240 | print "My effective uid can read $file\n"; | |
241 | } | |
242 | ||
36477c24 | 243 | use File::stat qw(:FIELDS); |
244 | stat($file) or die "No $file: $!"; | |
592b6146 | 245 | if ( ($st_mode & 0111) && ($st_nlink > 1) ) { |
36477c24 | 246 | print "$file is executable with lotsa links\n"; |
247 | } | |
248 | ||
249 | =head1 DESCRIPTION | |
250 | ||
251 | This module's default exports override the core stat() | |
252 | and lstat() functions, replacing them with versions that return | |
253 | "File::stat" objects. This object has methods that | |
254 | return the similarly named structure field name from the | |
255 | stat(2) function; namely, | |
256 | dev, | |
257 | ino, | |
258 | mode, | |
259 | nlink, | |
260 | uid, | |
261 | gid, | |
262 | rdev, | |
263 | size, | |
264 | atime, | |
265 | mtime, | |
266 | ctime, | |
267 | blksize, | |
268 | and | |
269 | blocks. | |
270 | ||
6cf0ee86 BM |
271 | As of version 1.02 (provided with perl 5.12) the object provides C<"-X"> |
272 | overloading, so you can call filetest operators (C<-f>, C<-x>, and so | |
273 | on) on it. It also provides a C<< ->cando >> method, called like | |
274 | ||
275 | $st->cando( ACCESS, EFFECTIVE ) | |
276 | ||
277 | where I<ACCESS> is one of C<S_IRUSR>, C<S_IWUSR> or C<S_IXUSR> from the | |
278 | L<Fcntl|Fcntl> module, and I<EFFECTIVE> indicates whether to use | |
279 | effective (true) or real (false) ids. The method interprets the C<mode>, | |
280 | C<uid> and C<gid> fields, and returns whether or not the current process | |
281 | would be allowed the specified access. | |
282 | ||
283 | If you don't want to use the objects, you may import the C<< ->cando >> | |
284 | method into your namespace as a regular function called C<stat_cando>. | |
285 | This takes an arrayref containing the return values of C<stat> or | |
286 | C<lstat> as its first argument, and interprets it for you. | |
287 | ||
36477c24 | 288 | You may also import all the structure fields directly into your namespace |
289 | as regular variables using the :FIELDS import tag. (Note that this still | |
290 | overrides your stat() and lstat() functions.) Access these fields as | |
291 | variables named with a preceding C<st_> in front their method names. | |
292 | Thus, C<$stat_obj-E<gt>dev()> corresponds to $st_dev if you import | |
293 | the fields. | |
294 | ||
295 | To access this functionality without the core overrides, | |
296 | pass the C<use> an empty import list, and then access | |
297 | function functions with their full qualified names. | |
298 | On the other hand, the built-ins are still available | |
299 | via the C<CORE::> pseudo-package. | |
300 | ||
5c4d9947 JH |
301 | =head1 BUGS |
302 | ||
303 | As of Perl 5.8.0 after using this module you cannot use the implicit | |
304 | C<$_> or the special filehandle C<_> with stat() or lstat(), trying | |
305 | to do so leads into strange errors. The workaround is for C<$_> to | |
306 | be explicit | |
307 | ||
308 | my $stat_obj = stat $_; | |
309 | ||
310 | and for C<_> to explicitly populate the object using the unexported | |
311 | and undocumented populate() function with CORE::stat(): | |
312 | ||
313 | my $stat_obj = File::stat::populate(CORE::stat(_)); | |
314 | ||
6cf0ee86 BM |
315 | =head1 ERRORS |
316 | ||
317 | =over 4 | |
318 | ||
319 | =item -%s is not implemented on a File::stat object | |
320 | ||
321 | The filetest operators C<-t>, C<-T> and C<-B> are not implemented, as | |
322 | they require more information than just a stat buffer. | |
323 | ||
324 | =back | |
325 | ||
326 | =head1 WARNINGS | |
327 | ||
328 | These can all be disabled with | |
329 | ||
330 | no warnings "File::stat"; | |
331 | ||
332 | =over 4 | |
333 | ||
334 | =item File::stat ignores use filetest 'access' | |
335 | ||
336 | You have tried to use one of the C<-rwxRWX> filetests with C<use | |
337 | filetest 'access'> in effect. C<File::stat> will ignore the pragma, and | |
338 | just use the information in the C<mode> member as usual. | |
339 | ||
340 | =item File::stat ignores VMS ACLs | |
341 | ||
342 | VMS systems have a permissions structure that cannot be completely | |
343 | represented in a stat buffer, and unlike on other systems the builtin | |
344 | filetest operators respect this. The C<File::stat> overloads, however, | |
345 | do not, since the information required is not available. | |
346 | ||
347 | =back | |
348 | ||
36477c24 | 349 | =head1 NOTE |
350 | ||
8cc95fdb | 351 | While this class is currently implemented using the Class::Struct |
36477c24 | 352 | module to build a struct-like class, you shouldn't rely upon this. |
353 | ||
354 | =head1 AUTHOR | |
355 | ||
356 | Tom Christiansen |