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Diffstat (limited to 'gl/stat.c')
-rw-r--r-- | gl/stat.c | 438 |
1 files changed, 438 insertions, 0 deletions
diff --git a/gl/stat.c b/gl/stat.c new file mode 100644 index 0000000..7987e26 --- /dev/null +++ b/gl/stat.c | |||
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1 | /* Work around platform bugs in stat. | ||
2 | Copyright (C) 2009-2023 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 <string.h> | ||
59 | #include "filename.h" | ||
60 | #include "malloca.h" | ||
61 | |||
62 | #ifdef WINDOWS_NATIVE | ||
63 | # define WIN32_LEAN_AND_MEAN | ||
64 | # include <windows.h> | ||
65 | # include "stat-w32.h" | ||
66 | /* Don't assume that UNICODE is not defined. */ | ||
67 | # undef WIN32_FIND_DATA | ||
68 | # define WIN32_FIND_DATA WIN32_FIND_DATAA | ||
69 | # undef CreateFile | ||
70 | # define CreateFile CreateFileA | ||
71 | # undef FindFirstFile | ||
72 | # define FindFirstFile FindFirstFileA | ||
73 | #endif | ||
74 | |||
75 | #ifdef WINDOWS_NATIVE | ||
76 | /* Return TRUE if the given file name denotes an UNC root. */ | ||
77 | static BOOL | ||
78 | is_unc_root (const char *rname) | ||
79 | { | ||
80 | /* Test whether it has the syntax '\\server\share'. */ | ||
81 | if (ISSLASH (rname[0]) && ISSLASH (rname[1])) | ||
82 | { | ||
83 | /* It starts with two slashes. Find the next slash. */ | ||
84 | const char *p = rname + 2; | ||
85 | const char *q = p; | ||
86 | while (*q != '\0' && !ISSLASH (*q)) | ||
87 | q++; | ||
88 | if (q > p && *q != '\0') | ||
89 | { | ||
90 | /* Found the next slash at q. */ | ||
91 | q++; | ||
92 | const char *r = q; | ||
93 | while (*r != '\0' && !ISSLASH (*r)) | ||
94 | r++; | ||
95 | if (r > q && *r == '\0') | ||
96 | return TRUE; | ||
97 | } | ||
98 | } | ||
99 | return FALSE; | ||
100 | } | ||
101 | #endif | ||
102 | |||
103 | /* Store information about NAME into ST. Work around bugs with | ||
104 | trailing slashes. Mingw has other bugs (such as st_ino always | ||
105 | being 0 on success) which this wrapper does not work around. But | ||
106 | at least this implementation provides the ability to emulate fchdir | ||
107 | correctly. */ | ||
108 | |||
109 | int | ||
110 | rpl_stat (char const *name, struct stat *buf) | ||
111 | { | ||
112 | #ifdef WINDOWS_NATIVE | ||
113 | /* Fill the fields ourselves, because the original stat function returns | ||
114 | values for st_atime, st_mtime, st_ctime that depend on the current time | ||
115 | zone. See | ||
116 | <https://lists.gnu.org/r/bug-gnulib/2017-04/msg00134.html> */ | ||
117 | /* XXX Should we convert to wchar_t* and prepend '\\?\', in order to work | ||
118 | around length limitations | ||
119 | <https://docs.microsoft.com/en-us/windows/desktop/FileIO/naming-a-file> ? */ | ||
120 | |||
121 | /* POSIX <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13> | ||
122 | specifies: "More than two leading <slash> characters shall be treated as | ||
123 | a single <slash> character." */ | ||
124 | if (ISSLASH (name[0]) && ISSLASH (name[1]) && ISSLASH (name[2])) | ||
125 | { | ||
126 | name += 2; | ||
127 | while (ISSLASH (name[1])) | ||
128 | name++; | ||
129 | } | ||
130 | |||
131 | size_t len = strlen (name); | ||
132 | size_t drive_prefix_len = (HAS_DEVICE (name) ? 2 : 0); | ||
133 | |||
134 | /* Remove trailing slashes (except the very first one, at position | ||
135 | drive_prefix_len), but remember their presence. */ | ||
136 | size_t rlen; | ||
137 | bool check_dir = false; | ||
138 | |||
139 | rlen = len; | ||
140 | while (rlen > drive_prefix_len && ISSLASH (name[rlen-1])) | ||
141 | { | ||
142 | check_dir = true; | ||
143 | if (rlen == drive_prefix_len + 1) | ||
144 | break; | ||
145 | rlen--; | ||
146 | } | ||
147 | |||
148 | /* Handle '' and 'C:'. */ | ||
149 | if (!check_dir && rlen == drive_prefix_len) | ||
150 | { | ||
151 | errno = ENOENT; | ||
152 | return -1; | ||
153 | } | ||
154 | |||
155 | /* Handle '\\'. */ | ||
156 | if (rlen == 1 && ISSLASH (name[0]) && len >= 2) | ||
157 | { | ||
158 | errno = ENOENT; | ||
159 | return -1; | ||
160 | } | ||
161 | |||
162 | const char *rname; | ||
163 | char *malloca_rname; | ||
164 | if (rlen == len) | ||
165 | { | ||
166 | rname = name; | ||
167 | malloca_rname = NULL; | ||
168 | } | ||
169 | else | ||
170 | { | ||
171 | malloca_rname = malloca (rlen + 1); | ||
172 | if (malloca_rname == NULL) | ||
173 | { | ||
174 | errno = ENOMEM; | ||
175 | return -1; | ||
176 | } | ||
177 | memcpy (malloca_rname, name, rlen); | ||
178 | malloca_rname[rlen] = '\0'; | ||
179 | rname = malloca_rname; | ||
180 | } | ||
181 | |||
182 | /* There are two ways to get at the requested information: | ||
183 | - by scanning the parent directory and examining the relevant | ||
184 | directory entry, | ||
185 | - by opening the file directly. | ||
186 | The first approach fails for root directories (e.g. 'C:\') and | ||
187 | UNC root directories (e.g. '\\server\share'). | ||
188 | The second approach fails for some system files (e.g. 'C:\pagefile.sys' | ||
189 | and 'C:\hiberfil.sys'): ERROR_SHARING_VIOLATION. | ||
190 | The second approach gives more information (in particular, correct | ||
191 | st_dev, st_ino, st_nlink fields). | ||
192 | So we use the second approach and, as a fallback except for root and | ||
193 | UNC root directories, also the first approach. */ | ||
194 | { | ||
195 | int ret; | ||
196 | |||
197 | { | ||
198 | /* Approach based on the file. */ | ||
199 | |||
200 | /* Open a handle to the file. | ||
201 | CreateFile | ||
202 | <https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-createfilea> | ||
203 | <https://docs.microsoft.com/en-us/windows/desktop/FileIO/creating-and-opening-files> */ | ||
204 | HANDLE h = | ||
205 | CreateFile (rname, | ||
206 | FILE_READ_ATTRIBUTES, | ||
207 | FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, | ||
208 | NULL, | ||
209 | OPEN_EXISTING, | ||
210 | /* FILE_FLAG_POSIX_SEMANTICS (treat file names that differ only | ||
211 | in case as different) makes sense only when applied to *all* | ||
212 | filesystem operations. */ | ||
213 | FILE_FLAG_BACKUP_SEMANTICS /* | FILE_FLAG_POSIX_SEMANTICS */, | ||
214 | NULL); | ||
215 | if (h != INVALID_HANDLE_VALUE) | ||
216 | { | ||
217 | ret = _gl_fstat_by_handle (h, rname, buf); | ||
218 | CloseHandle (h); | ||
219 | goto done; | ||
220 | } | ||
221 | } | ||
222 | |||
223 | /* Test for root and UNC root directories. */ | ||
224 | if ((rlen == drive_prefix_len + 1 && ISSLASH (rname[drive_prefix_len])) | ||
225 | || is_unc_root (rname)) | ||
226 | goto failed; | ||
227 | |||
228 | /* Fallback. */ | ||
229 | { | ||
230 | /* Approach based on the directory entry. */ | ||
231 | |||
232 | if (strchr (rname, '?') != NULL || strchr (rname, '*') != NULL) | ||
233 | { | ||
234 | /* Other Windows API functions would fail with error | ||
235 | ERROR_INVALID_NAME. */ | ||
236 | if (malloca_rname != NULL) | ||
237 | freea (malloca_rname); | ||
238 | errno = ENOENT; | ||
239 | return -1; | ||
240 | } | ||
241 | |||
242 | /* Get the details about the directory entry. This can be done through | ||
243 | FindFirstFile | ||
244 | <https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-findfirstfilea> | ||
245 | <https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ns-minwinbase-_win32_find_dataa> | ||
246 | or through | ||
247 | FindFirstFileEx with argument FindExInfoBasic | ||
248 | <https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-findfirstfileexa> | ||
249 | <https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ne-minwinbase-findex_info_levels> | ||
250 | <https://docs.microsoft.com/en-us/windows/desktop/api/minwinbase/ns-minwinbase-_win32_find_dataa> */ | ||
251 | WIN32_FIND_DATA info; | ||
252 | HANDLE h = FindFirstFile (rname, &info); | ||
253 | if (h == INVALID_HANDLE_VALUE) | ||
254 | goto failed; | ||
255 | |||
256 | /* Test for error conditions before starting to fill *buf. */ | ||
257 | if (sizeof (buf->st_size) <= 4 && info.nFileSizeHigh > 0) | ||
258 | { | ||
259 | FindClose (h); | ||
260 | if (malloca_rname != NULL) | ||
261 | freea (malloca_rname); | ||
262 | errno = EOVERFLOW; | ||
263 | return -1; | ||
264 | } | ||
265 | |||
266 | # if _GL_WINDOWS_STAT_INODES | ||
267 | buf->st_dev = 0; | ||
268 | # if _GL_WINDOWS_STAT_INODES == 2 | ||
269 | buf->st_ino._gl_ino[0] = buf->st_ino._gl_ino[1] = 0; | ||
270 | # else /* _GL_WINDOWS_STAT_INODES == 1 */ | ||
271 | buf->st_ino = 0; | ||
272 | # endif | ||
273 | # else | ||
274 | /* st_ino is not wide enough for identifying a file on a device. | ||
275 | Without st_ino, st_dev is pointless. */ | ||
276 | buf->st_dev = 0; | ||
277 | buf->st_ino = 0; | ||
278 | # endif | ||
279 | |||
280 | /* st_mode. */ | ||
281 | unsigned int mode = | ||
282 | /* XXX How to handle FILE_ATTRIBUTE_REPARSE_POINT ? */ | ||
283 | ((info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) ? _S_IFDIR | S_IEXEC_UGO : _S_IFREG) | ||
284 | | S_IREAD_UGO | ||
285 | | ((info.dwFileAttributes & FILE_ATTRIBUTE_READONLY) ? 0 : S_IWRITE_UGO); | ||
286 | if (!(info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)) | ||
287 | { | ||
288 | /* Determine whether the file is executable by looking at the file | ||
289 | name suffix. */ | ||
290 | if (info.nFileSizeHigh > 0 || info.nFileSizeLow > 0) | ||
291 | { | ||
292 | const char *last_dot = NULL; | ||
293 | const char *p; | ||
294 | for (p = info.cFileName; *p != '\0'; p++) | ||
295 | if (*p == '.') | ||
296 | last_dot = p; | ||
297 | if (last_dot != NULL) | ||
298 | { | ||
299 | const char *suffix = last_dot + 1; | ||
300 | if (_stricmp (suffix, "exe") == 0 | ||
301 | || _stricmp (suffix, "bat") == 0 | ||
302 | || _stricmp (suffix, "cmd") == 0 | ||
303 | || _stricmp (suffix, "com") == 0) | ||
304 | mode |= S_IEXEC_UGO; | ||
305 | } | ||
306 | } | ||
307 | } | ||
308 | buf->st_mode = mode; | ||
309 | |||
310 | /* st_nlink. Ignore hard links here. */ | ||
311 | buf->st_nlink = 1; | ||
312 | |||
313 | /* There's no easy way to map the Windows SID concept to an integer. */ | ||
314 | buf->st_uid = 0; | ||
315 | buf->st_gid = 0; | ||
316 | |||
317 | /* st_rdev is irrelevant for normal files and directories. */ | ||
318 | buf->st_rdev = 0; | ||
319 | |||
320 | /* st_size. */ | ||
321 | if (sizeof (buf->st_size) <= 4) | ||
322 | /* Range check already done above. */ | ||
323 | buf->st_size = info.nFileSizeLow; | ||
324 | else | ||
325 | buf->st_size = ((long long) info.nFileSizeHigh << 32) | (long long) info.nFileSizeLow; | ||
326 | |||
327 | /* st_atime, st_mtime, st_ctime. */ | ||
328 | # if _GL_WINDOWS_STAT_TIMESPEC | ||
329 | buf->st_atim = _gl_convert_FILETIME_to_timespec (&info.ftLastAccessTime); | ||
330 | buf->st_mtim = _gl_convert_FILETIME_to_timespec (&info.ftLastWriteTime); | ||
331 | buf->st_ctim = _gl_convert_FILETIME_to_timespec (&info.ftCreationTime); | ||
332 | # else | ||
333 | buf->st_atime = _gl_convert_FILETIME_to_POSIX (&info.ftLastAccessTime); | ||
334 | buf->st_mtime = _gl_convert_FILETIME_to_POSIX (&info.ftLastWriteTime); | ||
335 | buf->st_ctime = _gl_convert_FILETIME_to_POSIX (&info.ftCreationTime); | ||
336 | # endif | ||
337 | |||
338 | FindClose (h); | ||
339 | |||
340 | ret = 0; | ||
341 | } | ||
342 | |||
343 | done: | ||
344 | if (ret >= 0 && check_dir && !S_ISDIR (buf->st_mode)) | ||
345 | { | ||
346 | errno = ENOTDIR; | ||
347 | ret = -1; | ||
348 | } | ||
349 | if (malloca_rname != NULL) | ||
350 | { | ||
351 | int saved_errno = errno; | ||
352 | freea (malloca_rname); | ||
353 | errno = saved_errno; | ||
354 | } | ||
355 | return ret; | ||
356 | } | ||
357 | |||
358 | failed: | ||
359 | { | ||
360 | DWORD error = GetLastError (); | ||
361 | #if 0 | ||
362 | fprintf (stderr, "rpl_stat error 0x%x\n", (unsigned int) error); | ||
363 | #endif | ||
364 | |||
365 | if (malloca_rname != NULL) | ||
366 | freea (malloca_rname); | ||
367 | |||
368 | switch (error) | ||
369 | { | ||
370 | /* Some of these errors probably cannot happen with the specific flags | ||
371 | that we pass to CreateFile. But who knows... */ | ||
372 | case ERROR_FILE_NOT_FOUND: /* The last component of rname does not exist. */ | ||
373 | case ERROR_PATH_NOT_FOUND: /* Some directory component in rname does not exist. */ | ||
374 | case ERROR_BAD_PATHNAME: /* rname is such as '\\server'. */ | ||
375 | case ERROR_BAD_NET_NAME: /* rname is such as '\\server\nonexistentshare'. */ | ||
376 | case ERROR_INVALID_NAME: /* rname contains wildcards, misplaced colon, etc. */ | ||
377 | case ERROR_DIRECTORY: | ||
378 | errno = ENOENT; | ||
379 | break; | ||
380 | |||
381 | case ERROR_ACCESS_DENIED: /* rname is such as 'C:\System Volume Information\foo'. */ | ||
382 | case ERROR_SHARING_VIOLATION: /* rname is such as 'C:\pagefile.sys' (second approach only). */ | ||
383 | /* XXX map to EACCES or EPERM? */ | ||
384 | errno = EACCES; | ||
385 | break; | ||
386 | |||
387 | case ERROR_OUTOFMEMORY: | ||
388 | errno = ENOMEM; | ||
389 | break; | ||
390 | |||
391 | case ERROR_WRITE_PROTECT: | ||
392 | errno = EROFS; | ||
393 | break; | ||
394 | |||
395 | case ERROR_WRITE_FAULT: | ||
396 | case ERROR_READ_FAULT: | ||
397 | case ERROR_GEN_FAILURE: | ||
398 | errno = EIO; | ||
399 | break; | ||
400 | |||
401 | case ERROR_BUFFER_OVERFLOW: | ||
402 | case ERROR_FILENAME_EXCED_RANGE: | ||
403 | errno = ENAMETOOLONG; | ||
404 | break; | ||
405 | |||
406 | case ERROR_DELETE_PENDING: /* XXX map to EACCES or EPERM? */ | ||
407 | errno = EPERM; | ||
408 | break; | ||
409 | |||
410 | default: | ||
411 | errno = EINVAL; | ||
412 | break; | ||
413 | } | ||
414 | |||
415 | return -1; | ||
416 | } | ||
417 | #else | ||
418 | int result = orig_stat (name, buf); | ||
419 | if (result == 0) | ||
420 | { | ||
421 | # if REPLACE_FUNC_STAT_FILE | ||
422 | /* Solaris 9 mistakenly succeeds when given a non-directory with a | ||
423 | trailing slash. */ | ||
424 | if (!S_ISDIR (buf->st_mode)) | ||
425 | { | ||
426 | size_t len = strlen (name); | ||
427 | if (ISSLASH (name[len - 1])) | ||
428 | { | ||
429 | errno = ENOTDIR; | ||
430 | return -1; | ||
431 | } | ||
432 | } | ||
433 | # endif /* REPLACE_FUNC_STAT_FILE */ | ||
434 | result = stat_time_normalize (result, buf); | ||
435 | } | ||
436 | return result; | ||
437 | #endif | ||
438 | } | ||