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 | 37 | |
a2e78ff0 RB |
38 | /* |
39 | * Resolve the './' and '../' strings in the middle of a path using | |
40 | * our very own way to do it, so that it works even if the directory | |
41 | * does not exist | |
42 | */ | |
43 | LTTNG_HIDDEN | |
44 | char *utils_resolve_relative(const char *path) | |
45 | { | |
46 | char *next, *previous, *slash, *start_path, *absolute_path = NULL; | |
47 | ||
48 | /* Safety net */ | |
49 | if (path == NULL) { | |
50 | goto error; | |
51 | } | |
52 | ||
53 | /* Allocate memory for the absolute path */ | |
54 | absolute_path = zmalloc(PATH_MAX); | |
55 | if (absolute_path == NULL) { | |
56 | PERROR("zmalloc expand path"); | |
57 | goto error; | |
58 | } | |
59 | ||
60 | /* Copy the path in the absolute path */ | |
61 | strncpy(absolute_path, path, PATH_MAX); | |
62 | ||
63 | /* As long as we find '/./' in the path string */ | |
64 | while ((next = strstr(absolute_path, "/./"))) { | |
65 | ||
66 | /* We prepare the start_path not containing it */ | |
67 | start_path = strndup(absolute_path, next - absolute_path); | |
68 | ||
69 | /* And we concatenate it with the part after this string */ | |
70 | snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 2); | |
71 | ||
72 | free(start_path); | |
73 | } | |
74 | ||
75 | /* As long as we find '/../' in the path string */ | |
76 | while ((next = strstr(absolute_path, "/../"))) { | |
77 | /* If the path starts with '/../', there's a problem */ | |
78 | if (next == absolute_path) { | |
79 | ERR("%s: Path cannot be resolved", path); | |
80 | goto error; | |
81 | } | |
82 | ||
83 | /* We find the last level of directory */ | |
84 | previous = absolute_path; | |
85 | while ((slash = strpbrk(previous + 1, "/")) && slash != next) { | |
86 | previous = slash; | |
87 | } | |
88 | ||
89 | /* Then we prepare the start_path not containing it */ | |
90 | start_path = strndup(absolute_path, previous - absolute_path); | |
91 | ||
92 | /* And we concatenate it with the part after the '/../' */ | |
93 | snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 3); | |
94 | ||
95 | free(start_path); | |
96 | } | |
97 | ||
98 | return absolute_path; | |
99 | ||
100 | error: | |
101 | free(absolute_path); | |
102 | return NULL; | |
103 | } | |
104 | ||
105 | ||
81b86775 DG |
106 | /* |
107 | * Return the realpath(3) of the path even if the last directory token does not | |
108 | * exist. For example, with /tmp/test1/test2, if test2/ does not exist but the | |
109 | * /tmp/test1 does, the real path is returned. In normal time, realpath(3) | |
110 | * fails if the end point directory does not exist. | |
111 | */ | |
90e535ef | 112 | LTTNG_HIDDEN |
81b86775 DG |
113 | char *utils_expand_path(const char *path) |
114 | { | |
115 | const char *end_path = path; | |
116 | char *next, *cut_path = NULL, *expanded_path = NULL; | |
117 | ||
118 | /* Safety net */ | |
119 | if (path == NULL) { | |
120 | goto error; | |
121 | } | |
122 | ||
123 | /* Find last token delimited by '/' */ | |
124 | while ((next = strpbrk(end_path + 1, "/"))) { | |
125 | end_path = next; | |
126 | } | |
127 | ||
128 | /* Cut last token from original path */ | |
129 | cut_path = strndup(path, end_path - path); | |
130 | ||
131 | expanded_path = zmalloc(PATH_MAX); | |
132 | if (expanded_path == NULL) { | |
133 | PERROR("zmalloc expand path"); | |
134 | goto error; | |
135 | } | |
136 | ||
137 | expanded_path = realpath((char *)cut_path, expanded_path); | |
138 | if (expanded_path == NULL) { | |
139 | switch (errno) { | |
140 | case ENOENT: | |
141 | ERR("%s: No such file or directory", cut_path); | |
142 | break; | |
143 | default: | |
144 | PERROR("realpath utils expand path"); | |
145 | break; | |
146 | } | |
147 | goto error; | |
148 | } | |
149 | ||
150 | /* Add end part to expanded path */ | |
c30ce0b3 | 151 | strncat(expanded_path, end_path, PATH_MAX - strlen(expanded_path) - 1); |
81b86775 DG |
152 | |
153 | free(cut_path); | |
154 | return expanded_path; | |
155 | ||
156 | error: | |
157 | free(expanded_path); | |
158 | free(cut_path); | |
159 | return NULL; | |
160 | } | |
161 | ||
162 | /* | |
163 | * Create a pipe in dst. | |
164 | */ | |
90e535ef | 165 | LTTNG_HIDDEN |
81b86775 DG |
166 | int utils_create_pipe(int *dst) |
167 | { | |
168 | int ret; | |
169 | ||
170 | if (dst == NULL) { | |
171 | return -1; | |
172 | } | |
173 | ||
174 | ret = pipe(dst); | |
175 | if (ret < 0) { | |
176 | PERROR("create pipe"); | |
177 | } | |
178 | ||
179 | return ret; | |
180 | } | |
181 | ||
182 | /* | |
183 | * Create pipe and set CLOEXEC flag to both fd. | |
184 | * | |
185 | * Make sure the pipe opened by this function are closed at some point. Use | |
186 | * utils_close_pipe(). | |
187 | */ | |
90e535ef | 188 | LTTNG_HIDDEN |
81b86775 DG |
189 | int utils_create_pipe_cloexec(int *dst) |
190 | { | |
191 | int ret, i; | |
192 | ||
193 | if (dst == NULL) { | |
194 | return -1; | |
195 | } | |
196 | ||
197 | ret = utils_create_pipe(dst); | |
198 | if (ret < 0) { | |
199 | goto error; | |
200 | } | |
201 | ||
202 | for (i = 0; i < 2; i++) { | |
203 | ret = fcntl(dst[i], F_SETFD, FD_CLOEXEC); | |
204 | if (ret < 0) { | |
205 | PERROR("fcntl pipe cloexec"); | |
206 | goto error; | |
207 | } | |
208 | } | |
209 | ||
210 | error: | |
211 | return ret; | |
212 | } | |
213 | ||
094f381c MD |
214 | /* |
215 | * Create pipe and set fd flags to FD_CLOEXEC and O_NONBLOCK. | |
216 | * | |
217 | * Make sure the pipe opened by this function are closed at some point. Use | |
218 | * utils_close_pipe(). Using pipe() and fcntl rather than pipe2() to | |
219 | * support OSes other than Linux 2.6.23+. | |
220 | */ | |
221 | LTTNG_HIDDEN | |
222 | int utils_create_pipe_cloexec_nonblock(int *dst) | |
223 | { | |
224 | int ret, i; | |
225 | ||
226 | if (dst == NULL) { | |
227 | return -1; | |
228 | } | |
229 | ||
230 | ret = utils_create_pipe(dst); | |
231 | if (ret < 0) { | |
232 | goto error; | |
233 | } | |
234 | ||
235 | for (i = 0; i < 2; i++) { | |
236 | ret = fcntl(dst[i], F_SETFD, FD_CLOEXEC); | |
237 | if (ret < 0) { | |
238 | PERROR("fcntl pipe cloexec"); | |
239 | goto error; | |
240 | } | |
241 | /* | |
242 | * Note: we override any flag that could have been | |
243 | * previously set on the fd. | |
244 | */ | |
245 | ret = fcntl(dst[i], F_SETFL, O_NONBLOCK); | |
246 | if (ret < 0) { | |
247 | PERROR("fcntl pipe nonblock"); | |
248 | goto error; | |
249 | } | |
250 | } | |
251 | ||
252 | error: | |
253 | return ret; | |
254 | } | |
255 | ||
81b86775 DG |
256 | /* |
257 | * Close both read and write side of the pipe. | |
258 | */ | |
90e535ef | 259 | LTTNG_HIDDEN |
81b86775 DG |
260 | void utils_close_pipe(int *src) |
261 | { | |
262 | int i, ret; | |
263 | ||
264 | if (src == NULL) { | |
265 | return; | |
266 | } | |
267 | ||
268 | for (i = 0; i < 2; i++) { | |
269 | /* Safety check */ | |
270 | if (src[i] < 0) { | |
271 | continue; | |
272 | } | |
273 | ||
274 | ret = close(src[i]); | |
275 | if (ret) { | |
276 | PERROR("close pipe"); | |
277 | } | |
278 | } | |
279 | } | |
a4b92340 DG |
280 | |
281 | /* | |
282 | * Create a new string using two strings range. | |
283 | */ | |
90e535ef | 284 | LTTNG_HIDDEN |
a4b92340 DG |
285 | char *utils_strdupdelim(const char *begin, const char *end) |
286 | { | |
287 | char *str; | |
288 | ||
289 | str = zmalloc(end - begin + 1); | |
290 | if (str == NULL) { | |
291 | PERROR("zmalloc strdupdelim"); | |
292 | goto error; | |
293 | } | |
294 | ||
295 | memcpy(str, begin, end - begin); | |
296 | str[end - begin] = '\0'; | |
297 | ||
298 | error: | |
299 | return str; | |
300 | } | |
b662582b DG |
301 | |
302 | /* | |
303 | * Set CLOEXEC flag to the give file descriptor. | |
304 | */ | |
90e535ef | 305 | LTTNG_HIDDEN |
b662582b DG |
306 | int utils_set_fd_cloexec(int fd) |
307 | { | |
308 | int ret; | |
309 | ||
310 | if (fd < 0) { | |
311 | ret = -EINVAL; | |
312 | goto end; | |
313 | } | |
314 | ||
315 | ret = fcntl(fd, F_SETFD, FD_CLOEXEC); | |
316 | if (ret < 0) { | |
317 | PERROR("fcntl cloexec"); | |
318 | ret = -errno; | |
319 | } | |
320 | ||
321 | end: | |
322 | return ret; | |
323 | } | |
35f90c40 DG |
324 | |
325 | /* | |
326 | * Create pid file to the given path and filename. | |
327 | */ | |
90e535ef | 328 | LTTNG_HIDDEN |
35f90c40 DG |
329 | int utils_create_pid_file(pid_t pid, const char *filepath) |
330 | { | |
331 | int ret; | |
332 | FILE *fp; | |
333 | ||
334 | assert(filepath); | |
335 | ||
336 | fp = fopen(filepath, "w"); | |
337 | if (fp == NULL) { | |
338 | PERROR("open pid file %s", filepath); | |
339 | ret = -1; | |
340 | goto error; | |
341 | } | |
342 | ||
343 | ret = fprintf(fp, "%d\n", pid); | |
344 | if (ret < 0) { | |
345 | PERROR("fprintf pid file"); | |
346 | } | |
347 | ||
348 | fclose(fp); | |
349 | DBG("Pid %d written in file %s", pid, filepath); | |
350 | error: | |
351 | return ret; | |
352 | } | |
2d851108 DG |
353 | |
354 | /* | |
355 | * Recursively create directory using the given path and mode. | |
356 | * | |
357 | * On success, return 0 else a negative error code. | |
358 | */ | |
90e535ef | 359 | LTTNG_HIDDEN |
2d851108 DG |
360 | int utils_mkdir_recursive(const char *path, mode_t mode) |
361 | { | |
362 | char *p, tmp[PATH_MAX]; | |
2d851108 DG |
363 | size_t len; |
364 | int ret; | |
365 | ||
366 | assert(path); | |
367 | ||
368 | ret = snprintf(tmp, sizeof(tmp), "%s", path); | |
369 | if (ret < 0) { | |
370 | PERROR("snprintf mkdir"); | |
371 | goto error; | |
372 | } | |
373 | ||
374 | len = ret; | |
375 | if (tmp[len - 1] == '/') { | |
376 | tmp[len - 1] = 0; | |
377 | } | |
378 | ||
379 | for (p = tmp + 1; *p; p++) { | |
380 | if (*p == '/') { | |
381 | *p = 0; | |
382 | if (tmp[strlen(tmp) - 1] == '.' && | |
383 | tmp[strlen(tmp) - 2] == '.' && | |
384 | tmp[strlen(tmp) - 3] == '/') { | |
385 | ERR("Using '/../' is not permitted in the trace path (%s)", | |
386 | tmp); | |
387 | ret = -1; | |
388 | goto error; | |
389 | } | |
0c7bcad5 | 390 | ret = mkdir(tmp, mode); |
2d851108 | 391 | if (ret < 0) { |
0c7bcad5 MD |
392 | if (errno != EEXIST) { |
393 | PERROR("mkdir recursive"); | |
394 | ret = -errno; | |
395 | goto error; | |
2d851108 DG |
396 | } |
397 | } | |
398 | *p = '/'; | |
399 | } | |
400 | } | |
401 | ||
402 | ret = mkdir(tmp, mode); | |
403 | if (ret < 0) { | |
404 | if (errno != EEXIST) { | |
405 | PERROR("mkdir recursive last piece"); | |
406 | ret = -errno; | |
407 | } else { | |
408 | ret = 0; | |
409 | } | |
410 | } | |
411 | ||
412 | error: | |
413 | return ret; | |
414 | } | |
fe4477ee JD |
415 | |
416 | /* | |
417 | * Create the stream tracefile on disk. | |
418 | * | |
419 | * Return 0 on success or else a negative value. | |
420 | */ | |
bc182241 | 421 | LTTNG_HIDDEN |
07b86b52 | 422 | int utils_create_stream_file(const char *path_name, char *file_name, uint64_t size, |
309167d2 | 423 | uint64_t count, int uid, int gid, char *suffix) |
fe4477ee | 424 | { |
be96a7d1 | 425 | int ret, out_fd, flags, mode; |
309167d2 JD |
426 | char full_path[PATH_MAX], *path_name_suffix = NULL, *path; |
427 | char *extra = NULL; | |
fe4477ee JD |
428 | |
429 | assert(path_name); | |
430 | assert(file_name); | |
431 | ||
432 | ret = snprintf(full_path, sizeof(full_path), "%s/%s", | |
433 | path_name, file_name); | |
434 | if (ret < 0) { | |
435 | PERROR("snprintf create output file"); | |
436 | goto error; | |
437 | } | |
438 | ||
309167d2 JD |
439 | /* Setup extra string if suffix or/and a count is needed. */ |
440 | if (size > 0 && suffix) { | |
441 | ret = asprintf(&extra, "_%" PRIu64 "%s", count, suffix); | |
442 | } else if (size > 0) { | |
443 | ret = asprintf(&extra, "_%" PRIu64, count); | |
444 | } else if (suffix) { | |
445 | ret = asprintf(&extra, "%s", suffix); | |
446 | } | |
447 | if (ret < 0) { | |
448 | PERROR("Allocating extra string to name"); | |
449 | goto error; | |
450 | } | |
451 | ||
fe4477ee JD |
452 | /* |
453 | * If we split the trace in multiple files, we have to add the count at the | |
454 | * end of the tracefile name | |
455 | */ | |
309167d2 JD |
456 | if (extra) { |
457 | ret = asprintf(&path_name_suffix, "%s%s", full_path, extra); | |
fe4477ee | 458 | if (ret < 0) { |
309167d2 JD |
459 | PERROR("Allocating path name with extra string"); |
460 | goto error_free_suffix; | |
fe4477ee | 461 | } |
309167d2 | 462 | path = path_name_suffix; |
fe4477ee JD |
463 | } else { |
464 | path = full_path; | |
465 | } | |
466 | ||
be96a7d1 | 467 | flags = O_WRONLY | O_CREAT | O_TRUNC; |
0f907de1 | 468 | /* Open with 660 mode */ |
be96a7d1 DG |
469 | mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP; |
470 | ||
471 | if (uid < 0 || gid < 0) { | |
472 | out_fd = open(path, flags, mode); | |
473 | } else { | |
474 | out_fd = run_as_open(path, flags, mode, uid, gid); | |
475 | } | |
fe4477ee JD |
476 | if (out_fd < 0) { |
477 | PERROR("open stream path %s", path); | |
478 | goto error_open; | |
479 | } | |
480 | ret = out_fd; | |
481 | ||
482 | error_open: | |
309167d2 JD |
483 | free(path_name_suffix); |
484 | error_free_suffix: | |
485 | free(extra); | |
fe4477ee JD |
486 | error: |
487 | return ret; | |
488 | } | |
489 | ||
490 | /* | |
491 | * Change the output tracefile according to the given size and count The | |
492 | * new_count pointer is set during this operation. | |
493 | * | |
494 | * From the consumer, the stream lock MUST be held before calling this function | |
495 | * because we are modifying the stream status. | |
496 | * | |
497 | * Return 0 on success or else a negative value. | |
498 | */ | |
bc182241 | 499 | LTTNG_HIDDEN |
fe4477ee | 500 | int utils_rotate_stream_file(char *path_name, char *file_name, uint64_t size, |
309167d2 JD |
501 | uint64_t count, int uid, int gid, int out_fd, uint64_t *new_count, |
502 | int *stream_fd) | |
fe4477ee JD |
503 | { |
504 | int ret; | |
505 | ||
309167d2 JD |
506 | assert(new_count); |
507 | assert(stream_fd); | |
508 | ||
fe4477ee JD |
509 | ret = close(out_fd); |
510 | if (ret < 0) { | |
511 | PERROR("Closing tracefile"); | |
512 | goto error; | |
513 | } | |
514 | ||
515 | if (count > 0) { | |
516 | *new_count = (*new_count + 1) % count; | |
517 | } else { | |
518 | (*new_count)++; | |
519 | } | |
520 | ||
309167d2 JD |
521 | ret = utils_create_stream_file(path_name, file_name, size, *new_count, |
522 | uid, gid, 0); | |
523 | if (ret < 0) { | |
524 | goto error; | |
525 | } | |
526 | *stream_fd = ret; | |
527 | ||
528 | /* Success. */ | |
529 | ret = 0; | |
530 | ||
fe4477ee JD |
531 | error: |
532 | return ret; | |
533 | } | |
70d0b120 SM |
534 | |
535 | /** | |
536 | * Prints the error message corresponding to a regex error code. | |
537 | * | |
538 | * @param errcode The error code. | |
539 | * @param regex The regex object that produced the error code. | |
540 | */ | |
541 | static void regex_print_error(int errcode, regex_t *regex) | |
542 | { | |
543 | /* Get length of error message and allocate accordingly */ | |
544 | size_t length; | |
545 | char *buffer; | |
546 | ||
547 | assert(regex != NULL); | |
548 | ||
549 | length = regerror(errcode, regex, NULL, 0); | |
550 | if (length == 0) { | |
551 | ERR("regerror returned a length of 0"); | |
552 | return; | |
553 | } | |
554 | ||
555 | buffer = zmalloc(length); | |
556 | if (!buffer) { | |
557 | ERR("regex_print_error: zmalloc failed"); | |
558 | return; | |
559 | } | |
560 | ||
561 | /* Get and print error message */ | |
562 | regerror(errcode, regex, buffer, length); | |
563 | ERR("regex error: %s\n", buffer); | |
564 | free(buffer); | |
565 | ||
566 | } | |
567 | ||
568 | /** | |
569 | * Parse a string that represents a size in human readable format. It | |
570 | * supports decimal integers suffixed by 'k', 'M' or 'G'. | |
571 | * | |
572 | * The suffix multiply the integer by: | |
573 | * 'k': 1024 | |
574 | * 'M': 1024^2 | |
575 | * 'G': 1024^3 | |
576 | * | |
577 | * @param str The string to parse. | |
578 | * @param size Pointer to a size_t that will be filled with the | |
cfa9a5a2 | 579 | * resulting size. |
70d0b120 SM |
580 | * |
581 | * @return 0 on success, -1 on failure. | |
582 | */ | |
00a52467 | 583 | LTTNG_HIDDEN |
70d0b120 SM |
584 | int utils_parse_size_suffix(char *str, uint64_t *size) |
585 | { | |
586 | regex_t regex; | |
587 | int ret; | |
588 | const int nmatch = 3; | |
589 | regmatch_t suffix_match, matches[nmatch]; | |
590 | unsigned long long base_size; | |
591 | long shift = 0; | |
592 | ||
593 | if (!str) { | |
594 | return 0; | |
595 | } | |
596 | ||
597 | /* Compile regex */ | |
598 | ret = regcomp(®ex, "^\\(0x\\)\\{0,1\\}[0-9][0-9]*\\([kKMG]\\{0,1\\}\\)$", 0); | |
599 | if (ret != 0) { | |
600 | regex_print_error(ret, ®ex); | |
601 | ret = -1; | |
602 | goto end; | |
603 | } | |
604 | ||
605 | /* Match regex */ | |
606 | ret = regexec(®ex, str, nmatch, matches, 0); | |
607 | if (ret != 0) { | |
608 | ret = -1; | |
609 | goto free; | |
610 | } | |
611 | ||
612 | /* There is a match ! */ | |
613 | errno = 0; | |
614 | base_size = strtoull(str, NULL, 0); | |
615 | if (errno != 0) { | |
616 | PERROR("strtoull"); | |
617 | ret = -1; | |
618 | goto free; | |
619 | } | |
620 | ||
621 | /* Check if there is a suffix */ | |
622 | suffix_match = matches[2]; | |
623 | if (suffix_match.rm_eo - suffix_match.rm_so == 1) { | |
624 | switch (*(str + suffix_match.rm_so)) { | |
625 | case 'K': | |
626 | case 'k': | |
627 | shift = KIBI_LOG2; | |
628 | break; | |
629 | case 'M': | |
630 | shift = MEBI_LOG2; | |
631 | break; | |
632 | case 'G': | |
633 | shift = GIBI_LOG2; | |
634 | break; | |
635 | default: | |
636 | ERR("parse_human_size: invalid suffix"); | |
637 | ret = -1; | |
638 | goto free; | |
639 | } | |
640 | } | |
641 | ||
642 | *size = base_size << shift; | |
643 | ||
644 | /* Check for overflow */ | |
645 | if ((*size >> shift) != base_size) { | |
646 | ERR("parse_size_suffix: oops, overflow detected."); | |
647 | ret = -1; | |
648 | goto free; | |
649 | } | |
650 | ||
651 | ret = 0; | |
652 | ||
653 | free: | |
654 | regfree(®ex); | |
655 | end: | |
656 | return ret; | |
657 | } | |
cfa9a5a2 DG |
658 | |
659 | /* | |
660 | * fls: returns the position of the most significant bit. | |
661 | * Returns 0 if no bit is set, else returns the position of the most | |
662 | * significant bit (from 1 to 32 on 32-bit, from 1 to 64 on 64-bit). | |
663 | */ | |
664 | #if defined(__i386) || defined(__x86_64) | |
665 | static inline unsigned int fls_u32(uint32_t x) | |
666 | { | |
667 | int r; | |
668 | ||
669 | asm("bsrl %1,%0\n\t" | |
670 | "jnz 1f\n\t" | |
671 | "movl $-1,%0\n\t" | |
672 | "1:\n\t" | |
673 | : "=r" (r) : "rm" (x)); | |
674 | return r + 1; | |
675 | } | |
676 | #define HAS_FLS_U32 | |
677 | #endif | |
678 | ||
679 | #ifndef HAS_FLS_U32 | |
680 | static __attribute__((unused)) unsigned int fls_u32(uint32_t x) | |
681 | { | |
682 | unsigned int r = 32; | |
683 | ||
684 | if (!x) { | |
685 | return 0; | |
686 | } | |
687 | if (!(x & 0xFFFF0000U)) { | |
688 | x <<= 16; | |
689 | r -= 16; | |
690 | } | |
691 | if (!(x & 0xFF000000U)) { | |
692 | x <<= 8; | |
693 | r -= 8; | |
694 | } | |
695 | if (!(x & 0xF0000000U)) { | |
696 | x <<= 4; | |
697 | r -= 4; | |
698 | } | |
699 | if (!(x & 0xC0000000U)) { | |
700 | x <<= 2; | |
701 | r -= 2; | |
702 | } | |
703 | if (!(x & 0x80000000U)) { | |
704 | x <<= 1; | |
705 | r -= 1; | |
706 | } | |
707 | return r; | |
708 | } | |
709 | #endif | |
710 | ||
711 | /* | |
712 | * Return the minimum order for which x <= (1UL << order). | |
713 | * Return -1 if x is 0. | |
714 | */ | |
715 | LTTNG_HIDDEN | |
716 | int utils_get_count_order_u32(uint32_t x) | |
717 | { | |
718 | if (!x) { | |
719 | return -1; | |
720 | } | |
721 | ||
722 | return fls_u32(x - 1); | |
723 | } | |
feb0f3e5 AM |
724 | |
725 | /** | |
726 | * Obtain the value of LTTNG_HOME environment variable, if exists. | |
727 | * Otherwise returns the value of HOME. | |
728 | */ | |
00a52467 | 729 | LTTNG_HIDDEN |
feb0f3e5 AM |
730 | char *utils_get_home_dir(void) |
731 | { | |
732 | char *val = NULL; | |
733 | val = getenv(DEFAULT_LTTNG_HOME_ENV_VAR); | |
734 | if (val != NULL) { | |
735 | return val; | |
736 | } | |
737 | return getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR); | |
738 | } | |
26fe5938 DG |
739 | |
740 | /* | |
741 | * With the given format, fill dst with the time of len maximum siz. | |
742 | * | |
743 | * Return amount of bytes set in the buffer or else 0 on error. | |
744 | */ | |
745 | LTTNG_HIDDEN | |
746 | size_t utils_get_current_time_str(const char *format, char *dst, size_t len) | |
747 | { | |
748 | size_t ret; | |
749 | time_t rawtime; | |
750 | struct tm *timeinfo; | |
751 | ||
752 | assert(format); | |
753 | assert(dst); | |
754 | ||
755 | /* Get date and time for session path */ | |
756 | time(&rawtime); | |
757 | timeinfo = localtime(&rawtime); | |
758 | ret = strftime(dst, len, format, timeinfo); | |
759 | if (ret == 0) { | |
760 | ERR("Unable to strftime with format %s at dst %p of len %lu", format, | |
761 | dst, len); | |
762 | } | |
763 | ||
764 | return ret; | |
765 | } | |
6c71277b MD |
766 | |
767 | /* | |
768 | * Return the group ID matching name, else 0 if it cannot be found. | |
769 | */ | |
770 | LTTNG_HIDDEN | |
771 | gid_t utils_get_group_id(const char *name) | |
772 | { | |
773 | struct group *grp; | |
774 | ||
775 | grp = getgrnam(name); | |
776 | if (!grp) { | |
777 | static volatile int warn_once; | |
778 | ||
779 | if (!warn_once) { | |
780 | WARN("No tracing group detected"); | |
781 | warn_once = 1; | |
782 | } | |
783 | return 0; | |
784 | } | |
785 | return grp->gr_gid; | |
786 | } |