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Diffstat (limited to 'gl/stat.c')
-rw-r--r-- | gl/stat.c | 440 |
1 files changed, 440 insertions, 0 deletions
diff --git a/gl/stat.c b/gl/stat.c new file mode 100644 index 0000000..574489a --- /dev/null +++ b/gl/stat.c | |||
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1 | /* Work around platform bugs in stat. | ||
2 | Copyright (C) 2009-2022 Free Software Foundation, Inc. | ||
3 | |||
4 | This file is free software: you can redistribute it and/or modify | ||
5 | it under the terms of the GNU Lesser General Public License as | ||
6 | published by the Free Software Foundation; either version 2.1 of the | ||
7 | License, or (at your option) any later version. | ||
8 | |||
9 | This file is distributed in the hope that it will be useful, | ||
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
12 | GNU Lesser General Public License for more details. | ||
13 | |||
14 | You should have received a copy of the GNU Lesser General Public License | ||
15 | along with this program. If not, see <https://www.gnu.org/licenses/>. */ | ||
16 | |||
17 | /* Written by Eric Blake and Bruno Haible. */ | ||
18 | |||
19 | /* If the user's config.h happens to include <sys/stat.h>, let it include only | ||
20 | the system's <sys/stat.h> here, so that orig_stat doesn't recurse to | ||
21 | rpl_stat. */ | ||
22 | #define __need_system_sys_stat_h | ||
23 | #include <config.h> | ||
24 | |||
25 | /* Get the original definition of stat. It might be defined as a macro. */ | ||
26 | #include <sys/types.h> | ||
27 | #include <sys/stat.h> | ||
28 | #undef __need_system_sys_stat_h | ||
29 | |||
30 | #if defined _WIN32 && ! defined __CYGWIN__ | ||
31 | # define WINDOWS_NATIVE | ||
32 | #endif | ||
33 | |||
34 | #if !defined WINDOWS_NATIVE | ||
35 | |||
36 | static int | ||
37 | orig_stat (const char *filename, struct stat *buf) | ||
38 | { | ||
39 | return stat (filename, buf); | ||
40 | } | ||
41 | |||
42 | #endif | ||
43 | |||
44 | /* Specification. */ | ||
45 | #ifdef __osf__ | ||
46 | /* Write "sys/stat.h" here, not <sys/stat.h>, otherwise OSF/1 5.1 DTK cc | ||
47 | eliminates this include because of the preliminary #include <sys/stat.h> | ||
48 | above. */ | ||
49 | # include "sys/stat.h" | ||
50 | #else | ||
51 | # include <sys/stat.h> | ||
52 | #endif | ||
53 | |||
54 | #include "stat-time.h" | ||
55 | |||
56 | #include <errno.h> | ||
57 | #include <limits.h> | ||
58 | #include <stdbool.h> | ||
59 | #include <string.h> | ||
60 | #include "filename.h" | ||
61 | #include "malloca.h" | ||
62 | #include "verify.h" | ||
63 | |||
64 | #ifdef WINDOWS_NATIVE | ||
65 | # define WIN32_LEAN_AND_MEAN | ||
66 | # include <windows.h> | ||
67 | # include "stat-w32.h" | ||
68 | /* Don't assume that UNICODE is not defined. */ | ||
69 | # undef WIN32_FIND_DATA | ||
70 | # define WIN32_FIND_DATA WIN32_FIND_DATAA | ||
71 | # undef CreateFile | ||
72 | # define CreateFile CreateFileA | ||
73 | # undef FindFirstFile | ||
74 | # define FindFirstFile FindFirstFileA | ||
75 | #endif | ||
76 | |||
77 | #ifdef WINDOWS_NATIVE | ||
78 | /* Return TRUE if the given file name denotes an UNC root. */ | ||
79 | static BOOL | ||
80 | is_unc_root (const char *rname) | ||
81 | { | ||
82 | /* Test whether it has the syntax '\\server\share'. */ | ||
83 | if (ISSLASH (rname[0]) && ISSLASH (rname[1])) | ||
84 | { | ||
85 | /* It starts with two slashes. Find the next slash. */ | ||
86 | const char *p = rname + 2; | ||
87 | const char *q = p; | ||
88 | while (*q != '\0' && !ISSLASH (*q)) | ||
89 | q++; | ||
90 | if (q > p && *q != '\0') | ||
91 | { | ||
92 | /* Found the next slash at q. */ | ||
93 | q++; | ||
94 | const char *r = q; | ||
95 | while (*r != '\0' && !ISSLASH (*r)) | ||
96 | r++; | ||
97 | if (r > q && *r == '\0') | ||
98 | return TRUE; | ||
99 | } | ||
100 | } | ||
101 | return FALSE; | ||
102 | } | ||
103 | #endif | ||
104 | |||
105 | /* Store information about NAME into ST. Work around bugs with | ||
106 | trailing slashes. Mingw has other bugs (such as st_ino always | ||
107 | being 0 on success) which this wrapper does not work around. But | ||
108 | at least this implementation provides the ability to emulate fchdir | ||
109 | correctly. */ | ||
110 | |||
111 | int | ||
112 | rpl_stat (char const *name, struct stat *buf) | ||
113 | { | ||
114 | #ifdef WINDOWS_NATIVE | ||
115 | /* Fill the fields ourselves, because the original stat function returns | ||
116 | values for st_atime, st_mtime, st_ctime that depend on the current time | ||
117 | zone. See | ||
118 | <https://lists.gnu.org/r/bug-gnulib/2017-04/msg00134.html> */ | ||
119 | /* XXX Should we convert to wchar_t* and prepend '\\?\', in order to work | ||
120 | around length limitations | ||
121 | <https://docs.microsoft.com/en-us/windows/desktop/FileIO/naming-a-file> ? */ | ||
122 | |||
123 | /* POSIX <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13> | ||
124 | specifies: "More than two leading <slash> characters shall be treated as | ||
125 | a single <slash> character." */ | ||
126 | if (ISSLASH (name[0]) && ISSLASH (name[1]) && ISSLASH (name[2])) | ||
127 | { | ||
128 | name += 2; | ||
129 | while (ISSLASH (name[1])) | ||
130 | name++; | ||
131 | } | ||
132 | |||
133 | size_t len = strlen (name); | ||
134 | size_t drive_prefix_len = (HAS_DEVICE (name) ? 2 : 0); | ||
135 | |||
136 | /* Remove trailing slashes (except the very first one, at position | ||
137 | drive_prefix_len), but remember their presence. */ | ||
138 | size_t rlen; | ||
139 | bool check_dir = false; | ||
140 | |||
141 | rlen = len; | ||
142 | while (rlen > drive_prefix_len && ISSLASH (name[rlen-1])) | ||
143 | { | ||
144 | check_dir = true; | ||
145 | if (rlen == drive_prefix_len + 1) | ||
146 | break; | ||
147 | rlen--; | ||
148 | } | ||
149 | |||
150 | /* Handle '' and 'C:'. */ | ||
151 | if (!check_dir && rlen == drive_prefix_len) | ||
152 | { | ||
153 | errno = ENOENT; | ||
154 | return -1; | ||
155 | } | ||
156 | |||
157 | /* Handle '\\'. */ | ||
158 | if (rlen == 1 && ISSLASH (name[0]) && len >= 2) | ||
159 | { | ||
160 | errno = ENOENT; | ||
161 | return -1; | ||
162 | } | ||
163 | |||
164 | const char *rname; | ||
165 | char *malloca_rname; | ||
166 | if (rlen == len) | ||
167 | { | ||
168 | rname = name; | ||
169 | malloca_rname = NULL; | ||
170 | } | ||
171 | else | ||
172 | { | ||
173 | malloca_rname = malloca (rlen + 1); | ||
174 | if (malloca_rname == NULL) | ||
175 | { | ||
176 | errno = ENOMEM; | ||
177 | return -1; | ||
178 | } | ||
179 | memcpy (malloca_rname, name, rlen); | ||
180 | malloca_rname[rlen] = '\0'; | ||
181 | rname = malloca_rname; | ||
182 | } | ||
183 | |||
184 | /* There are two ways to get at the requested information: | ||
185 | - by scanning the parent directory and examining the relevant | ||
186 | directory entry, | ||
187 | - by opening the file directly. | ||
188 | The first approach fails for root directories (e.g. 'C:\') and | ||
189 | UNC root directories (e.g. '\\server\share'). | ||
190 | The second approach fails for some system files (e.g. 'C:\pagefile.sys' | ||
191 | and 'C:\hiberfil.sys'): ERROR_SHARING_VIOLATION. | ||
192 | The second approach gives more information (in particular, correct | ||
193 | st_dev, st_ino, st_nlink fields). | ||
194 | So we use the second approach and, as a fallback except for root and | ||
195 | UNC root directories, also the first approach. */ | ||
196 | { | ||
197 | int ret; | ||
198 | |||
199 | { | ||
200 | /* Approach based on the file. */ | ||
201 | |||
202 | /* Open a handle to the file. | ||
203 | CreateFile | ||
204 | <https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-createfilea> | ||
205 | <https://docs.microsoft.com/en-us/windows/desktop/FileIO/creating-and-opening-files> */ | ||
206 | HANDLE h = | ||
207 | CreateFile (rname, | ||
208 | FILE_READ_ATTRIBUTES, | ||
209 | FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, | ||
210 | NULL, | ||
211 | OPEN_EXISTING, | ||
212 | /* FILE_FLAG_POSIX_SEMANTICS (treat file names that differ only | ||
213 | in case as different) makes sense only when applied to *all* | ||
214 | filesystem operations. */ | ||
215 | FILE_FLAG_BACKUP_SEMANTICS /* | FILE_FLAG_POSIX_SEMANTICS */, | ||
216 | NULL); | ||
217 | if (h != INVALID_HANDLE_VALUE) | ||
218 | { | ||
219 | ret = _gl_fstat_by_handle (h, rname, buf); | ||
220 | CloseHandle (h); | ||
221 | goto done; | ||
222 | } | ||
223 | } | ||
224 | |||
225 | /* Test for root and UNC root directories. */ | ||
226 | if ((rlen == drive_prefix_len + 1 && ISSLASH (rname[drive_prefix_len])) | ||
227 | || is_unc_root (rname)) | ||
228 | goto failed; | ||
229 | |||
230 | /* Fallback. */ | ||
231 | { | ||
232 | /* Approach based on the directory entry. */ | ||
233 | |||
234 | if (strchr (rname, '?') != NULL || strchr (rname, '*') != NULL) | ||
235 | { | ||
236 | /* Other Windows API functions would fail with error | ||
237 | ERROR_INVALID_NAME. */ | ||
238 | if (malloca_rname != NULL) | ||
239 | freea (malloca_rname); | ||
240 | errno = ENOENT; | ||
241 | return -1; | ||
242 | } | ||
243 | |||
244 | /* Get the details about the directory entry. This can be done through | ||
245 | FindFirstFile | ||
246 | <https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-findfirstfilea> | ||
247 | <https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ns-minwinbase-_win32_find_dataa> | ||
248 | or through | ||
249 | FindFirstFileEx with argument FindExInfoBasic | ||
250 | <https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-findfirstfileexa> | ||
251 | <https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ne-minwinbase-findex_info_levels> | ||
252 | <https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ns-minwinbase-_win32_find_dataa> */ | ||
253 | WIN32_FIND_DATA info; | ||
254 | HANDLE h = FindFirstFile (rname, &info); | ||
255 | if (h == INVALID_HANDLE_VALUE) | ||
256 | goto failed; | ||
257 | |||
258 | /* Test for error conditions before starting to fill *buf. */ | ||
259 | if (sizeof (buf->st_size) <= 4 && info.nFileSizeHigh > 0) | ||
260 | { | ||
261 | FindClose (h); | ||
262 | if (malloca_rname != NULL) | ||
263 | freea (malloca_rname); | ||
264 | errno = EOVERFLOW; | ||
265 | return -1; | ||
266 | } | ||
267 | |||
268 | # if _GL_WINDOWS_STAT_INODES | ||
269 | buf->st_dev = 0; | ||
270 | # if _GL_WINDOWS_STAT_INODES == 2 | ||
271 | buf->st_ino._gl_ino[0] = buf->st_ino._gl_ino[1] = 0; | ||
272 | # else /* _GL_WINDOWS_STAT_INODES == 1 */ | ||
273 | buf->st_ino = 0; | ||
274 | # endif | ||
275 | # else | ||
276 | /* st_ino is not wide enough for identifying a file on a device. | ||
277 | Without st_ino, st_dev is pointless. */ | ||
278 | buf->st_dev = 0; | ||
279 | buf->st_ino = 0; | ||
280 | # endif | ||
281 | |||
282 | /* st_mode. */ | ||
283 | unsigned int mode = | ||
284 | /* XXX How to handle FILE_ATTRIBUTE_REPARSE_POINT ? */ | ||
285 | ((info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) ? _S_IFDIR | S_IEXEC_UGO : _S_IFREG) | ||
286 | | S_IREAD_UGO | ||
287 | | ((info.dwFileAttributes & FILE_ATTRIBUTE_READONLY) ? 0 : S_IWRITE_UGO); | ||
288 | if (!(info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)) | ||
289 | { | ||
290 | /* Determine whether the file is executable by looking at the file | ||
291 | name suffix. */ | ||
292 | if (info.nFileSizeHigh > 0 || info.nFileSizeLow > 0) | ||
293 | { | ||
294 | const char *last_dot = NULL; | ||
295 | const char *p; | ||
296 | for (p = info.cFileName; *p != '\0'; p++) | ||
297 | if (*p == '.') | ||
298 | last_dot = p; | ||
299 | if (last_dot != NULL) | ||
300 | { | ||
301 | const char *suffix = last_dot + 1; | ||
302 | if (_stricmp (suffix, "exe") == 0 | ||
303 | || _stricmp (suffix, "bat") == 0 | ||
304 | || _stricmp (suffix, "cmd") == 0 | ||
305 | || _stricmp (suffix, "com") == 0) | ||
306 | mode |= S_IEXEC_UGO; | ||
307 | } | ||
308 | } | ||
309 | } | ||
310 | buf->st_mode = mode; | ||
311 | |||
312 | /* st_nlink. Ignore hard links here. */ | ||
313 | buf->st_nlink = 1; | ||
314 | |||
315 | /* There's no easy way to map the Windows SID concept to an integer. */ | ||
316 | buf->st_uid = 0; | ||
317 | buf->st_gid = 0; | ||
318 | |||
319 | /* st_rdev is irrelevant for normal files and directories. */ | ||
320 | buf->st_rdev = 0; | ||
321 | |||
322 | /* st_size. */ | ||
323 | if (sizeof (buf->st_size) <= 4) | ||
324 | /* Range check already done above. */ | ||
325 | buf->st_size = info.nFileSizeLow; | ||
326 | else | ||
327 | buf->st_size = ((long long) info.nFileSizeHigh << 32) | (long long) info.nFileSizeLow; | ||
328 | |||
329 | /* st_atime, st_mtime, st_ctime. */ | ||
330 | # if _GL_WINDOWS_STAT_TIMESPEC | ||
331 | buf->st_atim = _gl_convert_FILETIME_to_timespec (&info.ftLastAccessTime); | ||
332 | buf->st_mtim = _gl_convert_FILETIME_to_timespec (&info.ftLastWriteTime); | ||
333 | buf->st_ctim = _gl_convert_FILETIME_to_timespec (&info.ftCreationTime); | ||
334 | # else | ||
335 | buf->st_atime = _gl_convert_FILETIME_to_POSIX (&info.ftLastAccessTime); | ||
336 | buf->st_mtime = _gl_convert_FILETIME_to_POSIX (&info.ftLastWriteTime); | ||
337 | buf->st_ctime = _gl_convert_FILETIME_to_POSIX (&info.ftCreationTime); | ||
338 | # endif | ||
339 | |||
340 | FindClose (h); | ||
341 | |||
342 | ret = 0; | ||
343 | } | ||
344 | |||
345 | done: | ||
346 | if (ret >= 0 && check_dir && !S_ISDIR (buf->st_mode)) | ||
347 | { | ||
348 | errno = ENOTDIR; | ||
349 | ret = -1; | ||
350 | } | ||
351 | if (malloca_rname != NULL) | ||
352 | { | ||
353 | int saved_errno = errno; | ||
354 | freea (malloca_rname); | ||
355 | errno = saved_errno; | ||
356 | } | ||
357 | return ret; | ||
358 | } | ||
359 | |||
360 | failed: | ||
361 | { | ||
362 | DWORD error = GetLastError (); | ||
363 | #if 0 | ||
364 | fprintf (stderr, "rpl_stat error 0x%x\n", (unsigned int) error); | ||
365 | #endif | ||
366 | |||
367 | if (malloca_rname != NULL) | ||
368 | freea (malloca_rname); | ||
369 | |||
370 | switch (error) | ||
371 | { | ||
372 | /* Some of these errors probably cannot happen with the specific flags | ||
373 | that we pass to CreateFile. But who knows... */ | ||
374 | case ERROR_FILE_NOT_FOUND: /* The last component of rname does not exist. */ | ||
375 | case ERROR_PATH_NOT_FOUND: /* Some directory component in rname does not exist. */ | ||
376 | case ERROR_BAD_PATHNAME: /* rname is such as '\\server'. */ | ||
377 | case ERROR_BAD_NET_NAME: /* rname is such as '\\server\nonexistentshare'. */ | ||
378 | case ERROR_INVALID_NAME: /* rname contains wildcards, misplaced colon, etc. */ | ||
379 | case ERROR_DIRECTORY: | ||
380 | errno = ENOENT; | ||
381 | break; | ||
382 | |||
383 | case ERROR_ACCESS_DENIED: /* rname is such as 'C:\System Volume Information\foo'. */ | ||
384 | case ERROR_SHARING_VIOLATION: /* rname is such as 'C:\pagefile.sys' (second approach only). */ | ||
385 | /* XXX map to EACCES or EPERM? */ | ||
386 | errno = EACCES; | ||
387 | break; | ||
388 | |||
389 | case ERROR_OUTOFMEMORY: | ||
390 | errno = ENOMEM; | ||
391 | break; | ||
392 | |||
393 | case ERROR_WRITE_PROTECT: | ||
394 | errno = EROFS; | ||
395 | break; | ||
396 | |||
397 | case ERROR_WRITE_FAULT: | ||
398 | case ERROR_READ_FAULT: | ||
399 | case ERROR_GEN_FAILURE: | ||
400 | errno = EIO; | ||
401 | break; | ||
402 | |||
403 | case ERROR_BUFFER_OVERFLOW: | ||
404 | case ERROR_FILENAME_EXCED_RANGE: | ||
405 | errno = ENAMETOOLONG; | ||
406 | break; | ||
407 | |||
408 | case ERROR_DELETE_PENDING: /* XXX map to EACCES or EPERM? */ | ||
409 | errno = EPERM; | ||
410 | break; | ||
411 | |||
412 | default: | ||
413 | errno = EINVAL; | ||
414 | break; | ||
415 | } | ||
416 | |||
417 | return -1; | ||
418 | } | ||
419 | #else | ||
420 | int result = orig_stat (name, buf); | ||
421 | if (result == 0) | ||
422 | { | ||
423 | # if REPLACE_FUNC_STAT_FILE | ||
424 | /* Solaris 9 mistakenly succeeds when given a non-directory with a | ||
425 | trailing slash. */ | ||
426 | if (!S_ISDIR (buf->st_mode)) | ||
427 | { | ||
428 | size_t len = strlen (name); | ||
429 | if (ISSLASH (name[len - 1])) | ||
430 | { | ||
431 | errno = ENOTDIR; | ||
432 | return -1; | ||
433 | } | ||
434 | } | ||
435 | # endif /* REPLACE_FUNC_STAT_FILE */ | ||
436 | result = stat_time_normalize (result, buf); | ||
437 | } | ||
438 | return result; | ||
439 | #endif | ||
440 | } | ||