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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
31bool perf_singlethreaded = true;
32
33void perf_set_singlethreaded(void)
34{
35 perf_singlethreaded = true;
36}
37
38void perf_set_multithreaded(void)
39{
40 perf_singlethreaded = false;
41}
42
43int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
44int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;
45
46int sysctl__max_stack(void)
47{
48 int value;
49
50 if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
51 sysctl_perf_event_max_stack = value;
52
53 if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
54 sysctl_perf_event_max_contexts_per_stack = value;
55
56 return sysctl_perf_event_max_stack;
57}
58
59bool sysctl__nmi_watchdog_enabled(void)
60{
61 static bool cached;
62 static bool nmi_watchdog;
63 int value;
64
65 if (cached)
66 return nmi_watchdog;
67
68 if (sysctl__read_int("kernel/nmi_watchdog", &value) < 0)
69 return false;
70
71 nmi_watchdog = (value > 0) ? true : false;
72 cached = true;
73
74 return nmi_watchdog;
75}
76
77bool test_attr__enabled;
78
79bool perf_host = true;
80bool perf_guest = false;
81
82void event_attr_init(struct perf_event_attr *attr)
83{
84 if (!perf_host)
85 attr->exclude_host = 1;
86 if (!perf_guest)
87 attr->exclude_guest = 1;
88 /* to capture ABI version */
89 attr->size = sizeof(*attr);
90}
91
92int mkdir_p(char *path, mode_t mode)
93{
94 struct stat st;
95 int err;
96 char *d = path;
97
98 if (*d != '/')
99 return -1;
100
101 if (stat(path, &st) == 0)
102 return 0;
103
104 while (*++d == '/');
105
106 while ((d = strchr(d, '/'))) {
107 *d = '\0';
108 err = stat(path, &st) && mkdir(path, mode);
109 *d++ = '/';
110 if (err)
111 return -1;
112 while (*d == '/')
113 ++d;
114 }
115 return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
116}
117
118static bool match_pat(char *file, const char **pat)
119{
120 int i = 0;
121
122 if (!pat)
123 return true;
124
125 while (pat[i]) {
126 if (strglobmatch(file, pat[i]))
127 return true;
128
129 i++;
130 }
131
132 return false;
133}
134
135/*
136 * The depth specify how deep the removal will go.
137 * 0 - will remove only files under the 'path' directory
138 * 1 .. x - will dive in x-level deep under the 'path' directory
139 *
140 * If specified the pat is array of string patterns ended with NULL,
141 * which are checked upon every file/directory found. Only matching
142 * ones are removed.
143 *
144 * The function returns:
145 * 0 on success
146 * -1 on removal failure with errno set
147 * -2 on pattern failure
148 */
149static int rm_rf_depth_pat(const char *path, int depth, const char **pat)
150{
151 DIR *dir;
152 int ret;
153 struct dirent *d;
154 char namebuf[PATH_MAX];
155 struct stat statbuf;
156
157 /* Do not fail if there's no file. */
158 ret = lstat(path, &statbuf);
159 if (ret)
160 return 0;
161
162 /* Try to remove any file we get. */
163 if (!(statbuf.st_mode & S_IFDIR))
164 return unlink(path);
165
166 /* We have directory in path. */
167 dir = opendir(path);
168 if (dir == NULL)
169 return -1;
170
171 while ((d = readdir(dir)) != NULL && !ret) {
172
173 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
174 continue;
175
176 if (!match_pat(d->d_name, pat)) {
177 ret = -2;
178 break;
179 }
180
181 scnprintf(namebuf, sizeof(namebuf), "%s/%s",
182 path, d->d_name);
183
184 /* We have to check symbolic link itself */
185 ret = lstat(namebuf, &statbuf);
186 if (ret < 0) {
187 pr_debug("stat failed: %s\n", namebuf);
188 break;
189 }
190
191 if (S_ISDIR(statbuf.st_mode))
192 ret = depth ? rm_rf_depth_pat(namebuf, depth - 1, pat) : 0;
193 else
194 ret = unlink(namebuf);
195 }
196 closedir(dir);
197
198 if (ret < 0)
199 return ret;
200
201 return rmdir(path);
202}
203
204static int rm_rf_a_kcore_dir(const char *path, const char *name)
205{
206 char kcore_dir_path[PATH_MAX];
207 const char *pat[] = {
208 "kcore",
209 "kallsyms",
210 "modules",
211 NULL,
212 };
213
214 snprintf(kcore_dir_path, sizeof(kcore_dir_path), "%s/%s", path, name);
215
216 return rm_rf_depth_pat(kcore_dir_path, 0, pat);
217}
218
219static bool kcore_dir_filter(const char *name __maybe_unused, struct dirent *d)
220{
221 const char *pat[] = {
222 "kcore_dir",
223 "kcore_dir__[1-9]*",
224 NULL,
225 };
226
227 return match_pat(d->d_name, pat);
228}
229
230static int rm_rf_kcore_dir(const char *path)
231{
232 struct strlist *kcore_dirs;
233 struct str_node *nd;
234 int ret;
235
236 kcore_dirs = lsdir(path, kcore_dir_filter);
237
238 if (!kcore_dirs)
239 return 0;
240
241 strlist__for_each_entry(nd, kcore_dirs) {
242 ret = rm_rf_a_kcore_dir(path, nd->s);
243 if (ret)
244 return ret;
245 }
246
247 strlist__delete(kcore_dirs);
248
249 return 0;
250}
251
252int rm_rf_perf_data(const char *path)
253{
254 const char *pat[] = {
255 "data",
256 "data.*",
257 NULL,
258 };
259
260 rm_rf_kcore_dir(path);
261
262 return rm_rf_depth_pat(path, 0, pat);
263}
264
265int rm_rf(const char *path)
266{
267 return rm_rf_depth_pat(path, INT_MAX, NULL);
268}
269
270/* A filter which removes dot files */
271bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d)
272{
273 return d->d_name[0] != '.';
274}
275
276/* lsdir reads a directory and store it in strlist */
277struct strlist *lsdir(const char *name,
278 bool (*filter)(const char *, struct dirent *))
279{
280 struct strlist *list = NULL;
281 DIR *dir;
282 struct dirent *d;
283
284 dir = opendir(name);
285 if (!dir)
286 return NULL;
287
288 list = strlist__new(NULL, NULL);
289 if (!list) {
290 errno = ENOMEM;
291 goto out;
292 }
293
294 while ((d = readdir(dir)) != NULL) {
295 if (!filter || filter(name, d))
296 strlist__add(list, d->d_name);
297 }
298
299out:
300 closedir(dir);
301 return list;
302}
303
304size_t hex_width(u64 v)
305{
306 size_t n = 1;
307
308 while ((v >>= 4))
309 ++n;
310
311 return n;
312}
313
314int perf_event_paranoid(void)
315{
316 int value;
317
318 if (sysctl__read_int("kernel/perf_event_paranoid", &value))
319 return INT_MAX;
320
321 return value;
322}
323
324bool perf_event_paranoid_check(int max_level)
325{
326 return perf_cap__capable(CAP_SYS_ADMIN) ||
327 perf_cap__capable(CAP_PERFMON) ||
328 perf_event_paranoid() <= max_level;
329}
330
331static int
332fetch_ubuntu_kernel_version(unsigned int *puint)
333{
334 ssize_t len;
335 size_t line_len = 0;
336 char *ptr, *line = NULL;
337 int version, patchlevel, sublevel, err;
338 FILE *vsig;
339
340 if (!puint)
341 return 0;
342
343 vsig = fopen("/proc/version_signature", "r");
344 if (!vsig) {
345 pr_debug("Open /proc/version_signature failed: %s\n",
346 strerror(errno));
347 return -1;
348 }
349
350 len = getline(&line, &line_len, vsig);
351 fclose(vsig);
352 err = -1;
353 if (len <= 0) {
354 pr_debug("Reading from /proc/version_signature failed: %s\n",
355 strerror(errno));
356 goto errout;
357 }
358
359 ptr = strrchr(line, ' ');
360 if (!ptr) {
361 pr_debug("Parsing /proc/version_signature failed: %s\n", line);
362 goto errout;
363 }
364
365 err = sscanf(ptr + 1, "%d.%d.%d",
366 &version, &patchlevel, &sublevel);
367 if (err != 3) {
368 pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
369 line);
370 goto errout;
371 }
372
373 *puint = (version << 16) + (patchlevel << 8) + sublevel;
374 err = 0;
375errout:
376 free(line);
377 return err;
378}
379
380int
381fetch_kernel_version(unsigned int *puint, char *str,
382 size_t str_size)
383{
384 struct utsname utsname;
385 int version, patchlevel, sublevel, err;
386 bool int_ver_ready = false;
387
388 if (access("/proc/version_signature", R_OK) == 0)
389 if (!fetch_ubuntu_kernel_version(puint))
390 int_ver_ready = true;
391
392 if (uname(&utsname))
393 return -1;
394
395 if (str && str_size) {
396 strncpy(str, utsname.release, str_size);
397 str[str_size - 1] = '\0';
398 }
399
400 if (!puint || int_ver_ready)
401 return 0;
402
403 err = sscanf(utsname.release, "%d.%d.%d",
404 &version, &patchlevel, &sublevel);
405
406 if (err != 3) {
407 pr_debug("Unable to get kernel version from uname '%s'\n",
408 utsname.release);
409 return -1;
410 }
411
412 *puint = (version << 16) + (patchlevel << 8) + sublevel;
413 return 0;
414}
415
416int perf_tip(char **strp, const char *dirpath)
417{
418 struct strlist *tips;
419 struct str_node *node;
420 struct strlist_config conf = {
421 .dirname = dirpath,
422 .file_only = true,
423 };
424 int ret = 0;
425
426 *strp = NULL;
427 tips = strlist__new("tips.txt", &conf);
428 if (tips == NULL)
429 return -errno;
430
431 if (strlist__nr_entries(tips) == 0)
432 goto out;
433
434 node = strlist__entry(tips, random() % strlist__nr_entries(tips));
435 if (asprintf(strp, "Tip: %s", node->s) < 0)
436 ret = -ENOMEM;
437
438out:
439 strlist__delete(tips);
440
441 return ret;
442}
443
444char *perf_exe(char *buf, int len)
445{
446 int n = readlink("/proc/self/exe", buf, len);
447 if (n > 0) {
448 buf[n] = 0;
449 return buf;
450 }
451 return strcpy(buf, "perf");
452}
453
454void perf_debuginfod_setup(struct perf_debuginfod *di)
455{
456 /*
457 * By default '!di->set' we clear DEBUGINFOD_URLS, so debuginfod
458 * processing is not triggered, otherwise we set it to 'di->urls'
459 * value. If 'di->urls' is "system" we keep DEBUGINFOD_URLS value.
460 */
461 if (!di->set)
462 setenv("DEBUGINFOD_URLS", "", 1);
463 else if (di->urls && strcmp(di->urls, "system"))
464 setenv("DEBUGINFOD_URLS", di->urls, 1);
465
466 pr_debug("DEBUGINFOD_URLS=%s\n", getenv("DEBUGINFOD_URLS"));
467
468#ifndef HAVE_DEBUGINFOD_SUPPORT
469 if (di->set)
470 pr_warning("WARNING: debuginfod support requested, but perf is not built with it\n");
471#endif
472}
473
474/*
475 * Return a new filename prepended with task's root directory if it's in
476 * a chroot. Callers should free the returned string.
477 */
478char *filename_with_chroot(int pid, const char *filename)
479{
480 char buf[PATH_MAX];
481 char proc_root[32];
482 char *new_name = NULL;
483 int ret;
484
485 scnprintf(proc_root, sizeof(proc_root), "/proc/%d/root", pid);
486 ret = readlink(proc_root, buf, sizeof(buf) - 1);
487 if (ret <= 0)
488 return NULL;
489
490 /* readlink(2) does not append a null byte to buf */
491 buf[ret] = '\0';
492
493 if (!strcmp(buf, "/"))
494 return NULL;
495
496 if (strstr(buf, "(deleted)"))
497 return NULL;
498
499 if (asprintf(&new_name, "%s/%s", buf, filename) < 0)
500 return NULL;
501
502 return new_name;
503}
504
505/*
506 * Reallocate an array *arr of size *arr_sz so that it is big enough to contain
507 * x elements of size msz, initializing new entries to *init_val or zero if
508 * init_val is NULL
509 */
510int do_realloc_array_as_needed(void **arr, size_t *arr_sz, size_t x, size_t msz, const void *init_val)
511{
512 size_t new_sz = *arr_sz;
513 void *new_arr;
514 size_t i;
515
516 if (!new_sz)
517 new_sz = msz >= 64 ? 1 : roundup(64, msz); /* Start with at least 64 bytes */
518 while (x >= new_sz) {
519 if (check_mul_overflow(new_sz, (size_t)2, &new_sz))
520 return -ENOMEM;
521 }
522 if (new_sz == *arr_sz)
523 return 0;
524 new_arr = calloc(new_sz, msz);
525 if (!new_arr)
526 return -ENOMEM;
527 memcpy(new_arr, *arr, *arr_sz * msz);
528 if (init_val) {
529 for (i = *arr_sz; i < new_sz; i++)
530 memcpy(new_arr + (i * msz), init_val, msz);
531 }
532 *arr = new_arr;
533 *arr_sz = new_sz;
534 return 0;
535}
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 <unistd.h>
22#include "cap.h"
23#include "strlist.h"
24#include "string2.h"
25
26/*
27 * XXX We need to find a better place for these things...
28 */
29
30bool perf_singlethreaded = true;
31
32void perf_set_singlethreaded(void)
33{
34 perf_singlethreaded = true;
35}
36
37void perf_set_multithreaded(void)
38{
39 perf_singlethreaded = false;
40}
41
42int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
43int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;
44
45int sysctl__max_stack(void)
46{
47 int value;
48
49 if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
50 sysctl_perf_event_max_stack = value;
51
52 if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
53 sysctl_perf_event_max_contexts_per_stack = value;
54
55 return sysctl_perf_event_max_stack;
56}
57
58bool sysctl__nmi_watchdog_enabled(void)
59{
60 static bool cached;
61 static bool nmi_watchdog;
62 int value;
63
64 if (cached)
65 return nmi_watchdog;
66
67 if (sysctl__read_int("kernel/nmi_watchdog", &value) < 0)
68 return false;
69
70 nmi_watchdog = (value > 0) ? true : false;
71 cached = true;
72
73 return nmi_watchdog;
74}
75
76bool test_attr__enabled;
77
78bool perf_host = true;
79bool perf_guest = false;
80
81void event_attr_init(struct perf_event_attr *attr)
82{
83 if (!perf_host)
84 attr->exclude_host = 1;
85 if (!perf_guest)
86 attr->exclude_guest = 1;
87 /* to capture ABI version */
88 attr->size = sizeof(*attr);
89}
90
91int mkdir_p(char *path, mode_t mode)
92{
93 struct stat st;
94 int err;
95 char *d = path;
96
97 if (*d != '/')
98 return -1;
99
100 if (stat(path, &st) == 0)
101 return 0;
102
103 while (*++d == '/');
104
105 while ((d = strchr(d, '/'))) {
106 *d = '\0';
107 err = stat(path, &st) && mkdir(path, mode);
108 *d++ = '/';
109 if (err)
110 return -1;
111 while (*d == '/')
112 ++d;
113 }
114 return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
115}
116
117static bool match_pat(char *file, const char **pat)
118{
119 int i = 0;
120
121 if (!pat)
122 return true;
123
124 while (pat[i]) {
125 if (strglobmatch(file, pat[i]))
126 return true;
127
128 i++;
129 }
130
131 return false;
132}
133
134/*
135 * The depth specify how deep the removal will go.
136 * 0 - will remove only files under the 'path' directory
137 * 1 .. x - will dive in x-level deep under the 'path' directory
138 *
139 * If specified the pat is array of string patterns ended with NULL,
140 * which are checked upon every file/directory found. Only matching
141 * ones are removed.
142 *
143 * The function returns:
144 * 0 on success
145 * -1 on removal failure with errno set
146 * -2 on pattern failure
147 */
148static int rm_rf_depth_pat(const char *path, int depth, const char **pat)
149{
150 DIR *dir;
151 int ret;
152 struct dirent *d;
153 char namebuf[PATH_MAX];
154 struct stat statbuf;
155
156 /* Do not fail if there's no file. */
157 ret = lstat(path, &statbuf);
158 if (ret)
159 return 0;
160
161 /* Try to remove any file we get. */
162 if (!(statbuf.st_mode & S_IFDIR))
163 return unlink(path);
164
165 /* We have directory in path. */
166 dir = opendir(path);
167 if (dir == NULL)
168 return -1;
169
170 while ((d = readdir(dir)) != NULL && !ret) {
171
172 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
173 continue;
174
175 if (!match_pat(d->d_name, pat)) {
176 ret = -2;
177 break;
178 }
179
180 scnprintf(namebuf, sizeof(namebuf), "%s/%s",
181 path, d->d_name);
182
183 /* We have to check symbolic link itself */
184 ret = lstat(namebuf, &statbuf);
185 if (ret < 0) {
186 pr_debug("stat failed: %s\n", namebuf);
187 break;
188 }
189
190 if (S_ISDIR(statbuf.st_mode))
191 ret = depth ? rm_rf_depth_pat(namebuf, depth - 1, pat) : 0;
192 else
193 ret = unlink(namebuf);
194 }
195 closedir(dir);
196
197 if (ret < 0)
198 return ret;
199
200 return rmdir(path);
201}
202
203static int rm_rf_kcore_dir(const char *path)
204{
205 char kcore_dir_path[PATH_MAX];
206 const char *pat[] = {
207 "kcore",
208 "kallsyms",
209 "modules",
210 NULL,
211 };
212
213 snprintf(kcore_dir_path, sizeof(kcore_dir_path), "%s/kcore_dir", path);
214
215 return rm_rf_depth_pat(kcore_dir_path, 0, pat);
216}
217
218int rm_rf_perf_data(const char *path)
219{
220 const char *pat[] = {
221 "data",
222 "data.*",
223 NULL,
224 };
225
226 rm_rf_kcore_dir(path);
227
228 return rm_rf_depth_pat(path, 0, pat);
229}
230
231int rm_rf(const char *path)
232{
233 return rm_rf_depth_pat(path, INT_MAX, NULL);
234}
235
236/* A filter which removes dot files */
237bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d)
238{
239 return d->d_name[0] != '.';
240}
241
242/* lsdir reads a directory and store it in strlist */
243struct strlist *lsdir(const char *name,
244 bool (*filter)(const char *, struct dirent *))
245{
246 struct strlist *list = NULL;
247 DIR *dir;
248 struct dirent *d;
249
250 dir = opendir(name);
251 if (!dir)
252 return NULL;
253
254 list = strlist__new(NULL, NULL);
255 if (!list) {
256 errno = ENOMEM;
257 goto out;
258 }
259
260 while ((d = readdir(dir)) != NULL) {
261 if (!filter || filter(name, d))
262 strlist__add(list, d->d_name);
263 }
264
265out:
266 closedir(dir);
267 return list;
268}
269
270size_t hex_width(u64 v)
271{
272 size_t n = 1;
273
274 while ((v >>= 4))
275 ++n;
276
277 return n;
278}
279
280int perf_event_paranoid(void)
281{
282 int value;
283
284 if (sysctl__read_int("kernel/perf_event_paranoid", &value))
285 return INT_MAX;
286
287 return value;
288}
289
290bool perf_event_paranoid_check(int max_level)
291{
292 return perf_cap__capable(CAP_SYS_ADMIN) ||
293 perf_cap__capable(CAP_PERFMON) ||
294 perf_event_paranoid() <= max_level;
295}
296
297static int
298fetch_ubuntu_kernel_version(unsigned int *puint)
299{
300 ssize_t len;
301 size_t line_len = 0;
302 char *ptr, *line = NULL;
303 int version, patchlevel, sublevel, err;
304 FILE *vsig;
305
306 if (!puint)
307 return 0;
308
309 vsig = fopen("/proc/version_signature", "r");
310 if (!vsig) {
311 pr_debug("Open /proc/version_signature failed: %s\n",
312 strerror(errno));
313 return -1;
314 }
315
316 len = getline(&line, &line_len, vsig);
317 fclose(vsig);
318 err = -1;
319 if (len <= 0) {
320 pr_debug("Reading from /proc/version_signature failed: %s\n",
321 strerror(errno));
322 goto errout;
323 }
324
325 ptr = strrchr(line, ' ');
326 if (!ptr) {
327 pr_debug("Parsing /proc/version_signature failed: %s\n", line);
328 goto errout;
329 }
330
331 err = sscanf(ptr + 1, "%d.%d.%d",
332 &version, &patchlevel, &sublevel);
333 if (err != 3) {
334 pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
335 line);
336 goto errout;
337 }
338
339 *puint = (version << 16) + (patchlevel << 8) + sublevel;
340 err = 0;
341errout:
342 free(line);
343 return err;
344}
345
346int
347fetch_kernel_version(unsigned int *puint, char *str,
348 size_t str_size)
349{
350 struct utsname utsname;
351 int version, patchlevel, sublevel, err;
352 bool int_ver_ready = false;
353
354 if (access("/proc/version_signature", R_OK) == 0)
355 if (!fetch_ubuntu_kernel_version(puint))
356 int_ver_ready = true;
357
358 if (uname(&utsname))
359 return -1;
360
361 if (str && str_size) {
362 strncpy(str, utsname.release, str_size);
363 str[str_size - 1] = '\0';
364 }
365
366 if (!puint || int_ver_ready)
367 return 0;
368
369 err = sscanf(utsname.release, "%d.%d.%d",
370 &version, &patchlevel, &sublevel);
371
372 if (err != 3) {
373 pr_debug("Unable to get kernel version from uname '%s'\n",
374 utsname.release);
375 return -1;
376 }
377
378 *puint = (version << 16) + (patchlevel << 8) + sublevel;
379 return 0;
380}
381
382const char *perf_tip(const char *dirpath)
383{
384 struct strlist *tips;
385 struct str_node *node;
386 char *tip = NULL;
387 struct strlist_config conf = {
388 .dirname = dirpath,
389 .file_only = true,
390 };
391
392 tips = strlist__new("tips.txt", &conf);
393 if (tips == NULL)
394 return errno == ENOENT ? NULL :
395 "Tip: check path of tips.txt or get more memory! ;-p";
396
397 if (strlist__nr_entries(tips) == 0)
398 goto out;
399
400 node = strlist__entry(tips, random() % strlist__nr_entries(tips));
401 if (asprintf(&tip, "Tip: %s", node->s) < 0)
402 tip = (char *)"Tip: get more memory! ;-)";
403
404out:
405 strlist__delete(tips);
406
407 return tip;
408}
409
410char *perf_exe(char *buf, int len)
411{
412 int n = readlink("/proc/self/exe", buf, len);
413 if (n > 0) {
414 buf[n] = 0;
415 return buf;
416 }
417 return strcpy(buf, "perf");
418}