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1#include "../perf.h"
2#include "util.h"
3#include <api/fs/fs.h>
4#include <sys/mman.h>
5#ifdef HAVE_BACKTRACE_SUPPORT
6#include <execinfo.h>
7#endif
8#include <stdio.h>
9#include <stdlib.h>
10#include <string.h>
11#include <errno.h>
12#include <limits.h>
13#include <byteswap.h>
14#include <linux/kernel.h>
15
16/*
17 * XXX We need to find a better place for these things...
18 */
19unsigned int page_size;
20
21bool test_attr__enabled;
22
23bool perf_host = true;
24bool perf_guest = false;
25
26char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events";
27
28void event_attr_init(struct perf_event_attr *attr)
29{
30 if (!perf_host)
31 attr->exclude_host = 1;
32 if (!perf_guest)
33 attr->exclude_guest = 1;
34 /* to capture ABI version */
35 attr->size = sizeof(*attr);
36}
37
38int mkdir_p(char *path, mode_t mode)
39{
40 struct stat st;
41 int err;
42 char *d = path;
43
44 if (*d != '/')
45 return -1;
46
47 if (stat(path, &st) == 0)
48 return 0;
49
50 while (*++d == '/');
51
52 while ((d = strchr(d, '/'))) {
53 *d = '\0';
54 err = stat(path, &st) && mkdir(path, mode);
55 *d++ = '/';
56 if (err)
57 return -1;
58 while (*d == '/')
59 ++d;
60 }
61 return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
62}
63
64static int slow_copyfile(const char *from, const char *to, mode_t mode)
65{
66 int err = -1;
67 char *line = NULL;
68 size_t n;
69 FILE *from_fp = fopen(from, "r"), *to_fp;
70 mode_t old_umask;
71
72 if (from_fp == NULL)
73 goto out;
74
75 old_umask = umask(mode ^ 0777);
76 to_fp = fopen(to, "w");
77 umask(old_umask);
78 if (to_fp == NULL)
79 goto out_fclose_from;
80
81 while (getline(&line, &n, from_fp) > 0)
82 if (fputs(line, to_fp) == EOF)
83 goto out_fclose_to;
84 err = 0;
85out_fclose_to:
86 fclose(to_fp);
87 free(line);
88out_fclose_from:
89 fclose(from_fp);
90out:
91 return err;
92}
93
94int copyfile_mode(const char *from, const char *to, mode_t mode)
95{
96 int fromfd, tofd;
97 struct stat st;
98 void *addr;
99 int err = -1;
100
101 if (stat(from, &st))
102 goto out;
103
104 if (st.st_size == 0) /* /proc? do it slowly... */
105 return slow_copyfile(from, to, mode);
106
107 fromfd = open(from, O_RDONLY);
108 if (fromfd < 0)
109 goto out;
110
111 tofd = creat(to, mode);
112 if (tofd < 0)
113 goto out_close_from;
114
115 addr = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fromfd, 0);
116 if (addr == MAP_FAILED)
117 goto out_close_to;
118
119 if (write(tofd, addr, st.st_size) == st.st_size)
120 err = 0;
121
122 munmap(addr, st.st_size);
123out_close_to:
124 close(tofd);
125 if (err)
126 unlink(to);
127out_close_from:
128 close(fromfd);
129out:
130 return err;
131}
132
133int copyfile(const char *from, const char *to)
134{
135 return copyfile_mode(from, to, 0755);
136}
137
138unsigned long convert_unit(unsigned long value, char *unit)
139{
140 *unit = ' ';
141
142 if (value > 1000) {
143 value /= 1000;
144 *unit = 'K';
145 }
146
147 if (value > 1000) {
148 value /= 1000;
149 *unit = 'M';
150 }
151
152 if (value > 1000) {
153 value /= 1000;
154 *unit = 'G';
155 }
156
157 return value;
158}
159
160static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
161{
162 void *buf_start = buf;
163 size_t left = n;
164
165 while (left) {
166 ssize_t ret = is_read ? read(fd, buf, left) :
167 write(fd, buf, left);
168
169 if (ret <= 0)
170 return ret;
171
172 left -= ret;
173 buf += ret;
174 }
175
176 BUG_ON((size_t)(buf - buf_start) != n);
177 return n;
178}
179
180/*
181 * Read exactly 'n' bytes or return an error.
182 */
183ssize_t readn(int fd, void *buf, size_t n)
184{
185 return ion(true, fd, buf, n);
186}
187
188/*
189 * Write exactly 'n' bytes or return an error.
190 */
191ssize_t writen(int fd, void *buf, size_t n)
192{
193 return ion(false, fd, buf, n);
194}
195
196size_t hex_width(u64 v)
197{
198 size_t n = 1;
199
200 while ((v >>= 4))
201 ++n;
202
203 return n;
204}
205
206static int hex(char ch)
207{
208 if ((ch >= '0') && (ch <= '9'))
209 return ch - '0';
210 if ((ch >= 'a') && (ch <= 'f'))
211 return ch - 'a' + 10;
212 if ((ch >= 'A') && (ch <= 'F'))
213 return ch - 'A' + 10;
214 return -1;
215}
216
217/*
218 * While we find nice hex chars, build a long_val.
219 * Return number of chars processed.
220 */
221int hex2u64(const char *ptr, u64 *long_val)
222{
223 const char *p = ptr;
224 *long_val = 0;
225
226 while (*p) {
227 const int hex_val = hex(*p);
228
229 if (hex_val < 0)
230 break;
231
232 *long_val = (*long_val << 4) | hex_val;
233 p++;
234 }
235
236 return p - ptr;
237}
238
239/* Obtain a backtrace and print it to stdout. */
240#ifdef HAVE_BACKTRACE_SUPPORT
241void dump_stack(void)
242{
243 void *array[16];
244 size_t size = backtrace(array, ARRAY_SIZE(array));
245 char **strings = backtrace_symbols(array, size);
246 size_t i;
247
248 printf("Obtained %zd stack frames.\n", size);
249
250 for (i = 0; i < size; i++)
251 printf("%s\n", strings[i]);
252
253 free(strings);
254}
255#else
256void dump_stack(void) {}
257#endif
258
259void get_term_dimensions(struct winsize *ws)
260{
261 char *s = getenv("LINES");
262
263 if (s != NULL) {
264 ws->ws_row = atoi(s);
265 s = getenv("COLUMNS");
266 if (s != NULL) {
267 ws->ws_col = atoi(s);
268 if (ws->ws_row && ws->ws_col)
269 return;
270 }
271 }
272#ifdef TIOCGWINSZ
273 if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
274 ws->ws_row && ws->ws_col)
275 return;
276#endif
277 ws->ws_row = 25;
278 ws->ws_col = 80;
279}
280
281static void set_tracing_events_path(const char *mountpoint)
282{
283 snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s",
284 mountpoint, "tracing/events");
285}
286
287const char *perf_debugfs_mount(const char *mountpoint)
288{
289 const char *mnt;
290
291 mnt = debugfs_mount(mountpoint);
292 if (!mnt)
293 return NULL;
294
295 set_tracing_events_path(mnt);
296
297 return mnt;
298}
299
300void perf_debugfs_set_path(const char *mntpt)
301{
302 snprintf(debugfs_mountpoint, strlen(debugfs_mountpoint), "%s", mntpt);
303 set_tracing_events_path(mntpt);
304}
305
306static const char *find_debugfs(void)
307{
308 const char *path = perf_debugfs_mount(NULL);
309
310 if (!path)
311 fprintf(stderr, "Your kernel does not support the debugfs filesystem");
312
313 return path;
314}
315
316/*
317 * Finds the path to the debugfs/tracing
318 * Allocates the string and stores it.
319 */
320const char *find_tracing_dir(void)
321{
322 static char *tracing;
323 static int tracing_found;
324 const char *debugfs;
325
326 if (tracing_found)
327 return tracing;
328
329 debugfs = find_debugfs();
330 if (!debugfs)
331 return NULL;
332
333 tracing = malloc(strlen(debugfs) + 9);
334 if (!tracing)
335 return NULL;
336
337 sprintf(tracing, "%s/tracing", debugfs);
338
339 tracing_found = 1;
340 return tracing;
341}
342
343char *get_tracing_file(const char *name)
344{
345 const char *tracing;
346 char *file;
347
348 tracing = find_tracing_dir();
349 if (!tracing)
350 return NULL;
351
352 file = malloc(strlen(tracing) + strlen(name) + 2);
353 if (!file)
354 return NULL;
355
356 sprintf(file, "%s/%s", tracing, name);
357 return file;
358}
359
360void put_tracing_file(char *file)
361{
362 free(file);
363}
364
365int parse_nsec_time(const char *str, u64 *ptime)
366{
367 u64 time_sec, time_nsec;
368 char *end;
369
370 time_sec = strtoul(str, &end, 10);
371 if (*end != '.' && *end != '\0')
372 return -1;
373
374 if (*end == '.') {
375 int i;
376 char nsec_buf[10];
377
378 if (strlen(++end) > 9)
379 return -1;
380
381 strncpy(nsec_buf, end, 9);
382 nsec_buf[9] = '\0';
383
384 /* make it nsec precision */
385 for (i = strlen(nsec_buf); i < 9; i++)
386 nsec_buf[i] = '0';
387
388 time_nsec = strtoul(nsec_buf, &end, 10);
389 if (*end != '\0')
390 return -1;
391 } else
392 time_nsec = 0;
393
394 *ptime = time_sec * NSEC_PER_SEC + time_nsec;
395 return 0;
396}
397
398unsigned long parse_tag_value(const char *str, struct parse_tag *tags)
399{
400 struct parse_tag *i = tags;
401
402 while (i->tag) {
403 char *s;
404
405 s = strchr(str, i->tag);
406 if (s) {
407 unsigned long int value;
408 char *endptr;
409
410 value = strtoul(str, &endptr, 10);
411 if (s != endptr)
412 break;
413
414 if (value > ULONG_MAX / i->mult)
415 break;
416 value *= i->mult;
417 return value;
418 }
419 i++;
420 }
421
422 return (unsigned long) -1;
423}
424
425int filename__read_int(const char *filename, int *value)
426{
427 char line[64];
428 int fd = open(filename, O_RDONLY), err = -1;
429
430 if (fd < 0)
431 return -1;
432
433 if (read(fd, line, sizeof(line)) > 0) {
434 *value = atoi(line);
435 err = 0;
436 }
437
438 close(fd);
439 return err;
440}
441
442int filename__read_str(const char *filename, char **buf, size_t *sizep)
443{
444 size_t size = 0, alloc_size = 0;
445 void *bf = NULL, *nbf;
446 int fd, n, err = 0;
447
448 fd = open(filename, O_RDONLY);
449 if (fd < 0)
450 return -errno;
451
452 do {
453 if (size == alloc_size) {
454 alloc_size += BUFSIZ;
455 nbf = realloc(bf, alloc_size);
456 if (!nbf) {
457 err = -ENOMEM;
458 break;
459 }
460
461 bf = nbf;
462 }
463
464 n = read(fd, bf + size, alloc_size - size);
465 if (n < 0) {
466 if (size) {
467 pr_warning("read failed %d: %s\n",
468 errno, strerror(errno));
469 err = 0;
470 } else
471 err = -errno;
472
473 break;
474 }
475
476 size += n;
477 } while (n > 0);
478
479 if (!err) {
480 *sizep = size;
481 *buf = bf;
482 } else
483 free(bf);
484
485 close(fd);
486 return err;
487}
488
489const char *get_filename_for_perf_kvm(void)
490{
491 const char *filename;
492
493 if (perf_host && !perf_guest)
494 filename = strdup("perf.data.host");
495 else if (!perf_host && perf_guest)
496 filename = strdup("perf.data.guest");
497 else
498 filename = strdup("perf.data.kvm");
499
500 return filename;
501}
502
503int perf_event_paranoid(void)
504{
505 char path[PATH_MAX];
506 const char *procfs = procfs__mountpoint();
507 int value;
508
509 if (!procfs)
510 return INT_MAX;
511
512 scnprintf(path, PATH_MAX, "%s/sys/kernel/perf_event_paranoid", procfs);
513
514 if (filename__read_int(path, &value))
515 return INT_MAX;
516
517 return value;
518}
519
520void mem_bswap_32(void *src, int byte_size)
521{
522 u32 *m = src;
523 while (byte_size > 0) {
524 *m = bswap_32(*m);
525 byte_size -= sizeof(u32);
526 ++m;
527 }
528}
529
530void mem_bswap_64(void *src, int byte_size)
531{
532 u64 *m = src;
533
534 while (byte_size > 0) {
535 *m = bswap_64(*m);
536 byte_size -= sizeof(u64);
537 ++m;
538 }
539}
1// SPDX-License-Identifier: GPL-2.0
2#include "util.h"
3#include "debug.h"
4#include "event.h"
5#include <api/fs/fs.h>
6#include <sys/stat.h>
7#include <sys/utsname.h>
8#include <dirent.h>
9#include <fcntl.h>
10#include <inttypes.h>
11#include <signal.h>
12#include <stdio.h>
13#include <stdlib.h>
14#include <string.h>
15#include <errno.h>
16#include <limits.h>
17#include <linux/capability.h>
18#include <linux/kernel.h>
19#include <linux/log2.h>
20#include <linux/time64.h>
21#include <linux/overflow.h>
22#include <unistd.h>
23#include "cap.h"
24#include "strlist.h"
25#include "string2.h"
26
27/*
28 * XXX We need to find a better place for these things...
29 */
30
31const char *input_name;
32
33bool perf_singlethreaded = true;
34
35void perf_set_singlethreaded(void)
36{
37 perf_singlethreaded = true;
38}
39
40void perf_set_multithreaded(void)
41{
42 perf_singlethreaded = false;
43}
44
45int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
46int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;
47
48int sysctl__max_stack(void)
49{
50 int value;
51
52 if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
53 sysctl_perf_event_max_stack = value;
54
55 if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
56 sysctl_perf_event_max_contexts_per_stack = value;
57
58 return sysctl_perf_event_max_stack;
59}
60
61bool sysctl__nmi_watchdog_enabled(void)
62{
63 static bool cached;
64 static bool nmi_watchdog;
65 int value;
66
67 if (cached)
68 return nmi_watchdog;
69
70 if (sysctl__read_int("kernel/nmi_watchdog", &value) < 0)
71 return false;
72
73 nmi_watchdog = (value > 0) ? true : false;
74 cached = true;
75
76 return nmi_watchdog;
77}
78
79bool test_attr__enabled;
80
81bool exclude_GH_default;
82
83bool perf_host = true;
84bool perf_guest = false;
85
86void event_attr_init(struct perf_event_attr *attr)
87{
88 /* to capture ABI version */
89 attr->size = sizeof(*attr);
90
91 if (!exclude_GH_default)
92 return;
93
94 if (!perf_host)
95 attr->exclude_host = 1;
96 if (!perf_guest)
97 attr->exclude_guest = 1;
98}
99
100int mkdir_p(char *path, mode_t mode)
101{
102 struct stat st;
103 int err;
104 char *d = path;
105
106 if (*d != '/')
107 return -1;
108
109 if (stat(path, &st) == 0)
110 return 0;
111
112 while (*++d == '/');
113
114 while ((d = strchr(d, '/'))) {
115 *d = '\0';
116 err = stat(path, &st) && mkdir(path, mode);
117 *d++ = '/';
118 if (err)
119 return -1;
120 while (*d == '/')
121 ++d;
122 }
123 return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
124}
125
126static bool match_pat(char *file, const char **pat)
127{
128 int i = 0;
129
130 if (!pat)
131 return true;
132
133 while (pat[i]) {
134 if (strglobmatch(file, pat[i]))
135 return true;
136
137 i++;
138 }
139
140 return false;
141}
142
143/*
144 * The depth specify how deep the removal will go.
145 * 0 - will remove only files under the 'path' directory
146 * 1 .. x - will dive in x-level deep under the 'path' directory
147 *
148 * If specified the pat is array of string patterns ended with NULL,
149 * which are checked upon every file/directory found. Only matching
150 * ones are removed.
151 *
152 * The function returns:
153 * 0 on success
154 * -1 on removal failure with errno set
155 * -2 on pattern failure
156 */
157static int rm_rf_depth_pat(const char *path, int depth, const char **pat)
158{
159 DIR *dir;
160 int ret;
161 struct dirent *d;
162 char namebuf[PATH_MAX];
163 struct stat statbuf;
164
165 /* Do not fail if there's no file. */
166 ret = lstat(path, &statbuf);
167 if (ret)
168 return 0;
169
170 /* Try to remove any file we get. */
171 if (!(statbuf.st_mode & S_IFDIR))
172 return unlink(path);
173
174 /* We have directory in path. */
175 dir = opendir(path);
176 if (dir == NULL)
177 return -1;
178
179 while ((d = readdir(dir)) != NULL && !ret) {
180
181 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
182 continue;
183
184 if (!match_pat(d->d_name, pat)) {
185 ret = -2;
186 break;
187 }
188
189 scnprintf(namebuf, sizeof(namebuf), "%s/%s",
190 path, d->d_name);
191
192 /* We have to check symbolic link itself */
193 ret = lstat(namebuf, &statbuf);
194 if (ret < 0) {
195 pr_debug("stat failed: %s\n", namebuf);
196 break;
197 }
198
199 if (S_ISDIR(statbuf.st_mode))
200 ret = depth ? rm_rf_depth_pat(namebuf, depth - 1, pat) : 0;
201 else
202 ret = unlink(namebuf);
203 }
204 closedir(dir);
205
206 if (ret < 0)
207 return ret;
208
209 return rmdir(path);
210}
211
212static int rm_rf_a_kcore_dir(const char *path, const char *name)
213{
214 char kcore_dir_path[PATH_MAX];
215 const char *pat[] = {
216 "kcore",
217 "kallsyms",
218 "modules",
219 NULL,
220 };
221
222 snprintf(kcore_dir_path, sizeof(kcore_dir_path), "%s/%s", path, name);
223
224 return rm_rf_depth_pat(kcore_dir_path, 0, pat);
225}
226
227static bool kcore_dir_filter(const char *name __maybe_unused, struct dirent *d)
228{
229 const char *pat[] = {
230 "kcore_dir",
231 "kcore_dir__[1-9]*",
232 NULL,
233 };
234
235 return match_pat(d->d_name, pat);
236}
237
238static int rm_rf_kcore_dir(const char *path)
239{
240 struct strlist *kcore_dirs;
241 struct str_node *nd;
242 int ret;
243
244 kcore_dirs = lsdir(path, kcore_dir_filter);
245
246 if (!kcore_dirs)
247 return 0;
248
249 strlist__for_each_entry(nd, kcore_dirs) {
250 ret = rm_rf_a_kcore_dir(path, nd->s);
251 if (ret)
252 return ret;
253 }
254
255 strlist__delete(kcore_dirs);
256
257 return 0;
258}
259
260int rm_rf_perf_data(const char *path)
261{
262 const char *pat[] = {
263 "data",
264 "data.*",
265 NULL,
266 };
267
268 rm_rf_kcore_dir(path);
269
270 return rm_rf_depth_pat(path, 0, pat);
271}
272
273int rm_rf(const char *path)
274{
275 return rm_rf_depth_pat(path, INT_MAX, NULL);
276}
277
278/* A filter which removes dot files */
279bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d)
280{
281 return d->d_name[0] != '.';
282}
283
284/* lsdir reads a directory and store it in strlist */
285struct strlist *lsdir(const char *name,
286 bool (*filter)(const char *, struct dirent *))
287{
288 struct strlist *list = NULL;
289 DIR *dir;
290 struct dirent *d;
291
292 dir = opendir(name);
293 if (!dir)
294 return NULL;
295
296 list = strlist__new(NULL, NULL);
297 if (!list) {
298 errno = ENOMEM;
299 goto out;
300 }
301
302 while ((d = readdir(dir)) != NULL) {
303 if (!filter || filter(name, d))
304 strlist__add(list, d->d_name);
305 }
306
307out:
308 closedir(dir);
309 return list;
310}
311
312size_t hex_width(u64 v)
313{
314 size_t n = 1;
315
316 while ((v >>= 4))
317 ++n;
318
319 return n;
320}
321
322int perf_event_paranoid(void)
323{
324 int value;
325
326 if (sysctl__read_int("kernel/perf_event_paranoid", &value))
327 return INT_MAX;
328
329 return value;
330}
331
332bool perf_event_paranoid_check(int max_level)
333{
334 bool used_root;
335
336 if (perf_cap__capable(CAP_SYS_ADMIN, &used_root))
337 return true;
338
339 if (!used_root && perf_cap__capable(CAP_PERFMON, &used_root))
340 return true;
341
342 return perf_event_paranoid() <= max_level;
343}
344
345int perf_tip(char **strp, const char *dirpath)
346{
347 struct strlist *tips;
348 struct str_node *node;
349 struct strlist_config conf = {
350 .dirname = dirpath,
351 .file_only = true,
352 };
353 int ret = 0;
354
355 *strp = NULL;
356 tips = strlist__new("tips.txt", &conf);
357 if (tips == NULL)
358 return -errno;
359
360 if (strlist__nr_entries(tips) == 0)
361 goto out;
362
363 node = strlist__entry(tips, random() % strlist__nr_entries(tips));
364 if (asprintf(strp, "Tip: %s", node->s) < 0)
365 ret = -ENOMEM;
366
367out:
368 strlist__delete(tips);
369
370 return ret;
371}
372
373char *perf_exe(char *buf, int len)
374{
375 int n = readlink("/proc/self/exe", buf, len);
376 if (n > 0) {
377 buf[n] = 0;
378 return buf;
379 }
380 return strcpy(buf, "perf");
381}
382
383void perf_debuginfod_setup(struct perf_debuginfod *di)
384{
385 /*
386 * By default '!di->set' we clear DEBUGINFOD_URLS, so debuginfod
387 * processing is not triggered, otherwise we set it to 'di->urls'
388 * value. If 'di->urls' is "system" we keep DEBUGINFOD_URLS value.
389 */
390 if (!di->set)
391 setenv("DEBUGINFOD_URLS", "", 1);
392 else if (di->urls && strcmp(di->urls, "system"))
393 setenv("DEBUGINFOD_URLS", di->urls, 1);
394
395 pr_debug("DEBUGINFOD_URLS=%s\n", getenv("DEBUGINFOD_URLS"));
396
397#ifndef HAVE_DEBUGINFOD_SUPPORT
398 if (di->set)
399 pr_warning("WARNING: debuginfod support requested, but perf is not built with it\n");
400#endif
401}
402
403/*
404 * Return a new filename prepended with task's root directory if it's in
405 * a chroot. Callers should free the returned string.
406 */
407char *filename_with_chroot(int pid, const char *filename)
408{
409 char buf[PATH_MAX];
410 char proc_root[32];
411 char *new_name = NULL;
412 int ret;
413
414 scnprintf(proc_root, sizeof(proc_root), "/proc/%d/root", pid);
415 ret = readlink(proc_root, buf, sizeof(buf) - 1);
416 if (ret <= 0)
417 return NULL;
418
419 /* readlink(2) does not append a null byte to buf */
420 buf[ret] = '\0';
421
422 if (!strcmp(buf, "/"))
423 return NULL;
424
425 if (strstr(buf, "(deleted)"))
426 return NULL;
427
428 if (asprintf(&new_name, "%s/%s", buf, filename) < 0)
429 return NULL;
430
431 return new_name;
432}
433
434/*
435 * Reallocate an array *arr of size *arr_sz so that it is big enough to contain
436 * x elements of size msz, initializing new entries to *init_val or zero if
437 * init_val is NULL
438 */
439int do_realloc_array_as_needed(void **arr, size_t *arr_sz, size_t x, size_t msz, const void *init_val)
440{
441 size_t new_sz = *arr_sz;
442 void *new_arr;
443 size_t i;
444
445 if (!new_sz)
446 new_sz = msz >= 64 ? 1 : roundup(64, msz); /* Start with at least 64 bytes */
447 while (x >= new_sz) {
448 if (check_mul_overflow(new_sz, (size_t)2, &new_sz))
449 return -ENOMEM;
450 }
451 if (new_sz == *arr_sz)
452 return 0;
453 new_arr = calloc(new_sz, msz);
454 if (!new_arr)
455 return -ENOMEM;
456 if (*arr_sz)
457 memcpy(new_arr, *arr, *arr_sz * msz);
458 if (init_val) {
459 for (i = *arr_sz; i < new_sz; i++)
460 memcpy(new_arr + (i * msz), init_val, msz);
461 }
462 *arr = new_arr;
463 *arr_sz = new_sz;
464 return 0;
465}
466
467#ifndef HAVE_SCHED_GETCPU_SUPPORT
468int sched_getcpu(void)
469{
470#ifdef __NR_getcpu
471 unsigned int cpu;
472 int err = syscall(__NR_getcpu, &cpu, NULL, NULL);
473
474 if (!err)
475 return cpu;
476#else
477 errno = ENOSYS;
478#endif
479 return -1;
480}
481#endif
482
483#ifndef HAVE_SCANDIRAT_SUPPORT
484int scandirat(int dirfd, const char *dirp,
485 struct dirent ***namelist,
486 int (*filter)(const struct dirent *),
487 int (*compar)(const struct dirent **, const struct dirent **))
488{
489 char path[PATH_MAX];
490 int err, fd = openat(dirfd, dirp, O_PATH);
491
492 if (fd < 0)
493 return fd;
494
495 snprintf(path, sizeof(path), "/proc/%d/fd/%d", getpid(), fd);
496 err = scandir(path, namelist, filter, compar);
497 close(fd);
498 return err;
499}
500#endif