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 }