kernel/tools/perf/util/find-vdso-map.c

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