Commit | Line | Data |
---|---|---|
81b86775 DG |
1 | /* |
2 | * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com> | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify it | |
5 | * under the terms of the GNU General Public License, version 2 only, as | |
6 | * published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
11 | * more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License along with | |
14 | * this program; if not, write to the Free Software Foundation, Inc., 51 | |
15 | * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | |
16 | */ | |
17 | ||
18 | #define _GNU_SOURCE | |
35f90c40 | 19 | #include <assert.h> |
81b86775 DG |
20 | #include <ctype.h> |
21 | #include <fcntl.h> | |
22 | #include <limits.h> | |
23 | #include <stdlib.h> | |
24 | #include <string.h> | |
2d851108 | 25 | #include <sys/stat.h> |
0c7bcad5 | 26 | #include <sys/types.h> |
2d851108 | 27 | #include <unistd.h> |
fe4477ee | 28 | #include <inttypes.h> |
70d0b120 | 29 | #include <regex.h> |
6c71277b | 30 | #include <grp.h> |
81b86775 DG |
31 | |
32 | #include <common/common.h> | |
fe4477ee | 33 | #include <common/runas.h> |
81b86775 DG |
34 | |
35 | #include "utils.h" | |
feb0f3e5 | 36 | #include "defaults.h" |
81b86775 DG |
37 | |
38 | /* | |
39 | * Return the realpath(3) of the path even if the last directory token does not | |
40 | * exist. For example, with /tmp/test1/test2, if test2/ does not exist but the | |
41 | * /tmp/test1 does, the real path is returned. In normal time, realpath(3) | |
42 | * fails if the end point directory does not exist. | |
43 | */ | |
90e535ef | 44 | LTTNG_HIDDEN |
81b86775 DG |
45 | char *utils_expand_path(const char *path) |
46 | { | |
47 | const char *end_path = path; | |
48 | char *next, *cut_path = NULL, *expanded_path = NULL; | |
49 | ||
50 | /* Safety net */ | |
51 | if (path == NULL) { | |
52 | goto error; | |
53 | } | |
54 | ||
55 | /* Find last token delimited by '/' */ | |
56 | while ((next = strpbrk(end_path + 1, "/"))) { | |
57 | end_path = next; | |
58 | } | |
59 | ||
60 | /* Cut last token from original path */ | |
61 | cut_path = strndup(path, end_path - path); | |
62 | ||
63 | expanded_path = zmalloc(PATH_MAX); | |
64 | if (expanded_path == NULL) { | |
65 | PERROR("zmalloc expand path"); | |
66 | goto error; | |
67 | } | |
68 | ||
69 | expanded_path = realpath((char *)cut_path, expanded_path); | |
70 | if (expanded_path == NULL) { | |
71 | switch (errno) { | |
72 | case ENOENT: | |
73 | ERR("%s: No such file or directory", cut_path); | |
74 | break; | |
75 | default: | |
76 | PERROR("realpath utils expand path"); | |
77 | break; | |
78 | } | |
79 | goto error; | |
80 | } | |
81 | ||
82 | /* Add end part to expanded path */ | |
c30ce0b3 | 83 | strncat(expanded_path, end_path, PATH_MAX - strlen(expanded_path) - 1); |
81b86775 DG |
84 | |
85 | free(cut_path); | |
86 | return expanded_path; | |
87 | ||
88 | error: | |
89 | free(expanded_path); | |
90 | free(cut_path); | |
91 | return NULL; | |
92 | } | |
93 | ||
94 | /* | |
95 | * Create a pipe in dst. | |
96 | */ | |
90e535ef | 97 | LTTNG_HIDDEN |
81b86775 DG |
98 | int utils_create_pipe(int *dst) |
99 | { | |
100 | int ret; | |
101 | ||
102 | if (dst == NULL) { | |
103 | return -1; | |
104 | } | |
105 | ||
106 | ret = pipe(dst); | |
107 | if (ret < 0) { | |
108 | PERROR("create pipe"); | |
109 | } | |
110 | ||
111 | return ret; | |
112 | } | |
113 | ||
114 | /* | |
115 | * Create pipe and set CLOEXEC flag to both fd. | |
116 | * | |
117 | * Make sure the pipe opened by this function are closed at some point. Use | |
118 | * utils_close_pipe(). | |
119 | */ | |
90e535ef | 120 | LTTNG_HIDDEN |
81b86775 DG |
121 | int utils_create_pipe_cloexec(int *dst) |
122 | { | |
123 | int ret, i; | |
124 | ||
125 | if (dst == NULL) { | |
126 | return -1; | |
127 | } | |
128 | ||
129 | ret = utils_create_pipe(dst); | |
130 | if (ret < 0) { | |
131 | goto error; | |
132 | } | |
133 | ||
134 | for (i = 0; i < 2; i++) { | |
135 | ret = fcntl(dst[i], F_SETFD, FD_CLOEXEC); | |
136 | if (ret < 0) { | |
137 | PERROR("fcntl pipe cloexec"); | |
138 | goto error; | |
139 | } | |
140 | } | |
141 | ||
142 | error: | |
143 | return ret; | |
144 | } | |
145 | ||
094f381c MD |
146 | /* |
147 | * Create pipe and set fd flags to FD_CLOEXEC and O_NONBLOCK. | |
148 | * | |
149 | * Make sure the pipe opened by this function are closed at some point. Use | |
150 | * utils_close_pipe(). Using pipe() and fcntl rather than pipe2() to | |
151 | * support OSes other than Linux 2.6.23+. | |
152 | */ | |
153 | LTTNG_HIDDEN | |
154 | int utils_create_pipe_cloexec_nonblock(int *dst) | |
155 | { | |
156 | int ret, i; | |
157 | ||
158 | if (dst == NULL) { | |
159 | return -1; | |
160 | } | |
161 | ||
162 | ret = utils_create_pipe(dst); | |
163 | if (ret < 0) { | |
164 | goto error; | |
165 | } | |
166 | ||
167 | for (i = 0; i < 2; i++) { | |
168 | ret = fcntl(dst[i], F_SETFD, FD_CLOEXEC); | |
169 | if (ret < 0) { | |
170 | PERROR("fcntl pipe cloexec"); | |
171 | goto error; | |
172 | } | |
173 | /* | |
174 | * Note: we override any flag that could have been | |
175 | * previously set on the fd. | |
176 | */ | |
177 | ret = fcntl(dst[i], F_SETFL, O_NONBLOCK); | |
178 | if (ret < 0) { | |
179 | PERROR("fcntl pipe nonblock"); | |
180 | goto error; | |
181 | } | |
182 | } | |
183 | ||
184 | error: | |
185 | return ret; | |
186 | } | |
187 | ||
81b86775 DG |
188 | /* |
189 | * Close both read and write side of the pipe. | |
190 | */ | |
90e535ef | 191 | LTTNG_HIDDEN |
81b86775 DG |
192 | void utils_close_pipe(int *src) |
193 | { | |
194 | int i, ret; | |
195 | ||
196 | if (src == NULL) { | |
197 | return; | |
198 | } | |
199 | ||
200 | for (i = 0; i < 2; i++) { | |
201 | /* Safety check */ | |
202 | if (src[i] < 0) { | |
203 | continue; | |
204 | } | |
205 | ||
206 | ret = close(src[i]); | |
207 | if (ret) { | |
208 | PERROR("close pipe"); | |
209 | } | |
210 | } | |
211 | } | |
a4b92340 DG |
212 | |
213 | /* | |
214 | * Create a new string using two strings range. | |
215 | */ | |
90e535ef | 216 | LTTNG_HIDDEN |
a4b92340 DG |
217 | char *utils_strdupdelim(const char *begin, const char *end) |
218 | { | |
219 | char *str; | |
220 | ||
221 | str = zmalloc(end - begin + 1); | |
222 | if (str == NULL) { | |
223 | PERROR("zmalloc strdupdelim"); | |
224 | goto error; | |
225 | } | |
226 | ||
227 | memcpy(str, begin, end - begin); | |
228 | str[end - begin] = '\0'; | |
229 | ||
230 | error: | |
231 | return str; | |
232 | } | |
b662582b DG |
233 | |
234 | /* | |
235 | * Set CLOEXEC flag to the give file descriptor. | |
236 | */ | |
90e535ef | 237 | LTTNG_HIDDEN |
b662582b DG |
238 | int utils_set_fd_cloexec(int fd) |
239 | { | |
240 | int ret; | |
241 | ||
242 | if (fd < 0) { | |
243 | ret = -EINVAL; | |
244 | goto end; | |
245 | } | |
246 | ||
247 | ret = fcntl(fd, F_SETFD, FD_CLOEXEC); | |
248 | if (ret < 0) { | |
249 | PERROR("fcntl cloexec"); | |
250 | ret = -errno; | |
251 | } | |
252 | ||
253 | end: | |
254 | return ret; | |
255 | } | |
35f90c40 DG |
256 | |
257 | /* | |
258 | * Create pid file to the given path and filename. | |
259 | */ | |
90e535ef | 260 | LTTNG_HIDDEN |
35f90c40 DG |
261 | int utils_create_pid_file(pid_t pid, const char *filepath) |
262 | { | |
263 | int ret; | |
264 | FILE *fp; | |
265 | ||
266 | assert(filepath); | |
267 | ||
268 | fp = fopen(filepath, "w"); | |
269 | if (fp == NULL) { | |
270 | PERROR("open pid file %s", filepath); | |
271 | ret = -1; | |
272 | goto error; | |
273 | } | |
274 | ||
275 | ret = fprintf(fp, "%d\n", pid); | |
276 | if (ret < 0) { | |
277 | PERROR("fprintf pid file"); | |
278 | } | |
279 | ||
280 | fclose(fp); | |
281 | DBG("Pid %d written in file %s", pid, filepath); | |
282 | error: | |
283 | return ret; | |
284 | } | |
2d851108 DG |
285 | |
286 | /* | |
287 | * Recursively create directory using the given path and mode. | |
288 | * | |
289 | * On success, return 0 else a negative error code. | |
290 | */ | |
90e535ef | 291 | LTTNG_HIDDEN |
2d851108 DG |
292 | int utils_mkdir_recursive(const char *path, mode_t mode) |
293 | { | |
294 | char *p, tmp[PATH_MAX]; | |
2d851108 DG |
295 | size_t len; |
296 | int ret; | |
297 | ||
298 | assert(path); | |
299 | ||
300 | ret = snprintf(tmp, sizeof(tmp), "%s", path); | |
301 | if (ret < 0) { | |
302 | PERROR("snprintf mkdir"); | |
303 | goto error; | |
304 | } | |
305 | ||
306 | len = ret; | |
307 | if (tmp[len - 1] == '/') { | |
308 | tmp[len - 1] = 0; | |
309 | } | |
310 | ||
311 | for (p = tmp + 1; *p; p++) { | |
312 | if (*p == '/') { | |
313 | *p = 0; | |
314 | if (tmp[strlen(tmp) - 1] == '.' && | |
315 | tmp[strlen(tmp) - 2] == '.' && | |
316 | tmp[strlen(tmp) - 3] == '/') { | |
317 | ERR("Using '/../' is not permitted in the trace path (%s)", | |
318 | tmp); | |
319 | ret = -1; | |
320 | goto error; | |
321 | } | |
0c7bcad5 | 322 | ret = mkdir(tmp, mode); |
2d851108 | 323 | if (ret < 0) { |
0c7bcad5 MD |
324 | if (errno != EEXIST) { |
325 | PERROR("mkdir recursive"); | |
326 | ret = -errno; | |
327 | goto error; | |
2d851108 DG |
328 | } |
329 | } | |
330 | *p = '/'; | |
331 | } | |
332 | } | |
333 | ||
334 | ret = mkdir(tmp, mode); | |
335 | if (ret < 0) { | |
336 | if (errno != EEXIST) { | |
337 | PERROR("mkdir recursive last piece"); | |
338 | ret = -errno; | |
339 | } else { | |
340 | ret = 0; | |
341 | } | |
342 | } | |
343 | ||
344 | error: | |
345 | return ret; | |
346 | } | |
fe4477ee JD |
347 | |
348 | /* | |
349 | * Create the stream tracefile on disk. | |
350 | * | |
351 | * Return 0 on success or else a negative value. | |
352 | */ | |
bc182241 | 353 | LTTNG_HIDDEN |
07b86b52 | 354 | int utils_create_stream_file(const char *path_name, char *file_name, uint64_t size, |
309167d2 | 355 | uint64_t count, int uid, int gid, char *suffix) |
fe4477ee | 356 | { |
be96a7d1 | 357 | int ret, out_fd, flags, mode; |
309167d2 JD |
358 | char full_path[PATH_MAX], *path_name_suffix = NULL, *path; |
359 | char *extra = NULL; | |
fe4477ee JD |
360 | |
361 | assert(path_name); | |
362 | assert(file_name); | |
363 | ||
364 | ret = snprintf(full_path, sizeof(full_path), "%s/%s", | |
365 | path_name, file_name); | |
366 | if (ret < 0) { | |
367 | PERROR("snprintf create output file"); | |
368 | goto error; | |
369 | } | |
370 | ||
309167d2 JD |
371 | /* Setup extra string if suffix or/and a count is needed. */ |
372 | if (size > 0 && suffix) { | |
373 | ret = asprintf(&extra, "_%" PRIu64 "%s", count, suffix); | |
374 | } else if (size > 0) { | |
375 | ret = asprintf(&extra, "_%" PRIu64, count); | |
376 | } else if (suffix) { | |
377 | ret = asprintf(&extra, "%s", suffix); | |
378 | } | |
379 | if (ret < 0) { | |
380 | PERROR("Allocating extra string to name"); | |
381 | goto error; | |
382 | } | |
383 | ||
fe4477ee JD |
384 | /* |
385 | * If we split the trace in multiple files, we have to add the count at the | |
386 | * end of the tracefile name | |
387 | */ | |
309167d2 JD |
388 | if (extra) { |
389 | ret = asprintf(&path_name_suffix, "%s%s", full_path, extra); | |
fe4477ee | 390 | if (ret < 0) { |
309167d2 JD |
391 | PERROR("Allocating path name with extra string"); |
392 | goto error_free_suffix; | |
fe4477ee | 393 | } |
309167d2 | 394 | path = path_name_suffix; |
fe4477ee JD |
395 | } else { |
396 | path = full_path; | |
397 | } | |
398 | ||
be96a7d1 | 399 | flags = O_WRONLY | O_CREAT | O_TRUNC; |
0f907de1 | 400 | /* Open with 660 mode */ |
be96a7d1 DG |
401 | mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP; |
402 | ||
403 | if (uid < 0 || gid < 0) { | |
404 | out_fd = open(path, flags, mode); | |
405 | } else { | |
406 | out_fd = run_as_open(path, flags, mode, uid, gid); | |
407 | } | |
fe4477ee JD |
408 | if (out_fd < 0) { |
409 | PERROR("open stream path %s", path); | |
410 | goto error_open; | |
411 | } | |
412 | ret = out_fd; | |
413 | ||
414 | error_open: | |
309167d2 JD |
415 | free(path_name_suffix); |
416 | error_free_suffix: | |
417 | free(extra); | |
fe4477ee JD |
418 | error: |
419 | return ret; | |
420 | } | |
421 | ||
422 | /* | |
423 | * Change the output tracefile according to the given size and count The | |
424 | * new_count pointer is set during this operation. | |
425 | * | |
426 | * From the consumer, the stream lock MUST be held before calling this function | |
427 | * because we are modifying the stream status. | |
428 | * | |
429 | * Return 0 on success or else a negative value. | |
430 | */ | |
bc182241 | 431 | LTTNG_HIDDEN |
fe4477ee | 432 | int utils_rotate_stream_file(char *path_name, char *file_name, uint64_t size, |
309167d2 JD |
433 | uint64_t count, int uid, int gid, int out_fd, uint64_t *new_count, |
434 | int *stream_fd) | |
fe4477ee JD |
435 | { |
436 | int ret; | |
437 | ||
309167d2 JD |
438 | assert(new_count); |
439 | assert(stream_fd); | |
440 | ||
fe4477ee JD |
441 | ret = close(out_fd); |
442 | if (ret < 0) { | |
443 | PERROR("Closing tracefile"); | |
444 | goto error; | |
445 | } | |
446 | ||
447 | if (count > 0) { | |
448 | *new_count = (*new_count + 1) % count; | |
449 | } else { | |
450 | (*new_count)++; | |
451 | } | |
452 | ||
309167d2 JD |
453 | ret = utils_create_stream_file(path_name, file_name, size, *new_count, |
454 | uid, gid, 0); | |
455 | if (ret < 0) { | |
456 | goto error; | |
457 | } | |
458 | *stream_fd = ret; | |
459 | ||
460 | /* Success. */ | |
461 | ret = 0; | |
462 | ||
fe4477ee JD |
463 | error: |
464 | return ret; | |
465 | } | |
70d0b120 SM |
466 | |
467 | /** | |
468 | * Prints the error message corresponding to a regex error code. | |
469 | * | |
470 | * @param errcode The error code. | |
471 | * @param regex The regex object that produced the error code. | |
472 | */ | |
473 | static void regex_print_error(int errcode, regex_t *regex) | |
474 | { | |
475 | /* Get length of error message and allocate accordingly */ | |
476 | size_t length; | |
477 | char *buffer; | |
478 | ||
479 | assert(regex != NULL); | |
480 | ||
481 | length = regerror(errcode, regex, NULL, 0); | |
482 | if (length == 0) { | |
483 | ERR("regerror returned a length of 0"); | |
484 | return; | |
485 | } | |
486 | ||
487 | buffer = zmalloc(length); | |
488 | if (!buffer) { | |
489 | ERR("regex_print_error: zmalloc failed"); | |
490 | return; | |
491 | } | |
492 | ||
493 | /* Get and print error message */ | |
494 | regerror(errcode, regex, buffer, length); | |
495 | ERR("regex error: %s\n", buffer); | |
496 | free(buffer); | |
497 | ||
498 | } | |
499 | ||
500 | /** | |
501 | * Parse a string that represents a size in human readable format. It | |
502 | * supports decimal integers suffixed by 'k', 'M' or 'G'. | |
503 | * | |
504 | * The suffix multiply the integer by: | |
505 | * 'k': 1024 | |
506 | * 'M': 1024^2 | |
507 | * 'G': 1024^3 | |
508 | * | |
509 | * @param str The string to parse. | |
510 | * @param size Pointer to a size_t that will be filled with the | |
cfa9a5a2 | 511 | * resulting size. |
70d0b120 SM |
512 | * |
513 | * @return 0 on success, -1 on failure. | |
514 | */ | |
00a52467 | 515 | LTTNG_HIDDEN |
70d0b120 SM |
516 | int utils_parse_size_suffix(char *str, uint64_t *size) |
517 | { | |
518 | regex_t regex; | |
519 | int ret; | |
520 | const int nmatch = 3; | |
521 | regmatch_t suffix_match, matches[nmatch]; | |
522 | unsigned long long base_size; | |
523 | long shift = 0; | |
524 | ||
525 | if (!str) { | |
526 | return 0; | |
527 | } | |
528 | ||
529 | /* Compile regex */ | |
530 | ret = regcomp(®ex, "^\\(0x\\)\\{0,1\\}[0-9][0-9]*\\([kKMG]\\{0,1\\}\\)$", 0); | |
531 | if (ret != 0) { | |
532 | regex_print_error(ret, ®ex); | |
533 | ret = -1; | |
534 | goto end; | |
535 | } | |
536 | ||
537 | /* Match regex */ | |
538 | ret = regexec(®ex, str, nmatch, matches, 0); | |
539 | if (ret != 0) { | |
540 | ret = -1; | |
541 | goto free; | |
542 | } | |
543 | ||
544 | /* There is a match ! */ | |
545 | errno = 0; | |
546 | base_size = strtoull(str, NULL, 0); | |
547 | if (errno != 0) { | |
548 | PERROR("strtoull"); | |
549 | ret = -1; | |
550 | goto free; | |
551 | } | |
552 | ||
553 | /* Check if there is a suffix */ | |
554 | suffix_match = matches[2]; | |
555 | if (suffix_match.rm_eo - suffix_match.rm_so == 1) { | |
556 | switch (*(str + suffix_match.rm_so)) { | |
557 | case 'K': | |
558 | case 'k': | |
559 | shift = KIBI_LOG2; | |
560 | break; | |
561 | case 'M': | |
562 | shift = MEBI_LOG2; | |
563 | break; | |
564 | case 'G': | |
565 | shift = GIBI_LOG2; | |
566 | break; | |
567 | default: | |
568 | ERR("parse_human_size: invalid suffix"); | |
569 | ret = -1; | |
570 | goto free; | |
571 | } | |
572 | } | |
573 | ||
574 | *size = base_size << shift; | |
575 | ||
576 | /* Check for overflow */ | |
577 | if ((*size >> shift) != base_size) { | |
578 | ERR("parse_size_suffix: oops, overflow detected."); | |
579 | ret = -1; | |
580 | goto free; | |
581 | } | |
582 | ||
583 | ret = 0; | |
584 | ||
585 | free: | |
586 | regfree(®ex); | |
587 | end: | |
588 | return ret; | |
589 | } | |
cfa9a5a2 DG |
590 | |
591 | /* | |
592 | * fls: returns the position of the most significant bit. | |
593 | * Returns 0 if no bit is set, else returns the position of the most | |
594 | * significant bit (from 1 to 32 on 32-bit, from 1 to 64 on 64-bit). | |
595 | */ | |
596 | #if defined(__i386) || defined(__x86_64) | |
597 | static inline unsigned int fls_u32(uint32_t x) | |
598 | { | |
599 | int r; | |
600 | ||
601 | asm("bsrl %1,%0\n\t" | |
602 | "jnz 1f\n\t" | |
603 | "movl $-1,%0\n\t" | |
604 | "1:\n\t" | |
605 | : "=r" (r) : "rm" (x)); | |
606 | return r + 1; | |
607 | } | |
608 | #define HAS_FLS_U32 | |
609 | #endif | |
610 | ||
611 | #ifndef HAS_FLS_U32 | |
612 | static __attribute__((unused)) unsigned int fls_u32(uint32_t x) | |
613 | { | |
614 | unsigned int r = 32; | |
615 | ||
616 | if (!x) { | |
617 | return 0; | |
618 | } | |
619 | if (!(x & 0xFFFF0000U)) { | |
620 | x <<= 16; | |
621 | r -= 16; | |
622 | } | |
623 | if (!(x & 0xFF000000U)) { | |
624 | x <<= 8; | |
625 | r -= 8; | |
626 | } | |
627 | if (!(x & 0xF0000000U)) { | |
628 | x <<= 4; | |
629 | r -= 4; | |
630 | } | |
631 | if (!(x & 0xC0000000U)) { | |
632 | x <<= 2; | |
633 | r -= 2; | |
634 | } | |
635 | if (!(x & 0x80000000U)) { | |
636 | x <<= 1; | |
637 | r -= 1; | |
638 | } | |
639 | return r; | |
640 | } | |
641 | #endif | |
642 | ||
643 | /* | |
644 | * Return the minimum order for which x <= (1UL << order). | |
645 | * Return -1 if x is 0. | |
646 | */ | |
647 | LTTNG_HIDDEN | |
648 | int utils_get_count_order_u32(uint32_t x) | |
649 | { | |
650 | if (!x) { | |
651 | return -1; | |
652 | } | |
653 | ||
654 | return fls_u32(x - 1); | |
655 | } | |
feb0f3e5 AM |
656 | |
657 | /** | |
658 | * Obtain the value of LTTNG_HOME environment variable, if exists. | |
659 | * Otherwise returns the value of HOME. | |
660 | */ | |
00a52467 | 661 | LTTNG_HIDDEN |
feb0f3e5 AM |
662 | char *utils_get_home_dir(void) |
663 | { | |
664 | char *val = NULL; | |
665 | val = getenv(DEFAULT_LTTNG_HOME_ENV_VAR); | |
666 | if (val != NULL) { | |
667 | return val; | |
668 | } | |
669 | return getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR); | |
670 | } | |
26fe5938 DG |
671 | |
672 | /* | |
673 | * With the given format, fill dst with the time of len maximum siz. | |
674 | * | |
675 | * Return amount of bytes set in the buffer or else 0 on error. | |
676 | */ | |
677 | LTTNG_HIDDEN | |
678 | size_t utils_get_current_time_str(const char *format, char *dst, size_t len) | |
679 | { | |
680 | size_t ret; | |
681 | time_t rawtime; | |
682 | struct tm *timeinfo; | |
683 | ||
684 | assert(format); | |
685 | assert(dst); | |
686 | ||
687 | /* Get date and time for session path */ | |
688 | time(&rawtime); | |
689 | timeinfo = localtime(&rawtime); | |
690 | ret = strftime(dst, len, format, timeinfo); | |
691 | if (ret == 0) { | |
692 | ERR("Unable to strftime with format %s at dst %p of len %lu", format, | |
693 | dst, len); | |
694 | } | |
695 | ||
696 | return ret; | |
697 | } | |
6c71277b MD |
698 | |
699 | /* | |
700 | * Return the group ID matching name, else 0 if it cannot be found. | |
701 | */ | |
702 | LTTNG_HIDDEN | |
703 | gid_t utils_get_group_id(const char *name) | |
704 | { | |
705 | struct group *grp; | |
706 | ||
707 | grp = getgrnam(name); | |
708 | if (!grp) { | |
709 | static volatile int warn_once; | |
710 | ||
711 | if (!warn_once) { | |
712 | WARN("No tracing group detected"); | |
713 | warn_once = 1; | |
714 | } | |
715 | return 0; | |
716 | } | |
717 | return grp->gr_gid; | |
718 | } |