GNU Linux-libre 4.19.211-gnu1
[releases.git] / tools / perf / util / find-vdso-map.c
1 // SPDX-License-Identifier: GPL-2.0
2 static int find_vdso_map(void **start, void **end)
3 {
4         FILE *maps;
5         char line[128];
6         int found = 0;
7
8         maps = fopen("/proc/self/maps", "r");
9         if (!maps) {
10                 fprintf(stderr, "vdso: cannot open maps\n");
11                 return -1;
12         }
13
14         while (!found && fgets(line, sizeof(line), maps)) {
15                 int m = -1;
16
17                 /* We care only about private r-x mappings. */
18                 if (2 != sscanf(line, "%p-%p r-xp %*x %*x:%*x %*u %n",
19                                 start, end, &m))
20                         continue;
21                 if (m < 0)
22                         continue;
23
24                 if (!strncmp(&line[m], VDSO__MAP_NAME,
25                              sizeof(VDSO__MAP_NAME) - 1))
26                         found = 1;
27         }
28
29         fclose(maps);
30         return !found;
31 }