tools/perf/util/tracepoint.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include "tracepoint.h"
   3
   4 #include <errno.h>
   5 #include <fcntl.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <sys/param.h>
   9 #include <unistd.h>
  10
  11 #include <api/fs/tracing_path.h>
  12 #include "fncache.h"
  13
  14 int tp_event_has_id(const char *dir_path, struct dirent *evt_dir)
  15 {
  16         char evt_path[MAXPATHLEN];
  17         int fd;
  18
  19         snprintf(evt_path, MAXPATHLEN, "%s/%s/id", dir_path, evt_dir->d_name);
  20         fd = open(evt_path, O_RDONLY);
  21         if (fd < 0)
  22                 return -EINVAL;
  23         close(fd);
  24
  25         return 0;
  26 }
  27
  28 /*
  29  * Check whether event is in <debugfs_mount_point>/tracing/events
  30  */
  31 bool is_valid_tracepoint(const char *event_string)
  32 {
  33         char *dst, *path = malloc(strlen(event_string) + 4); /* Space for "/id\0". */
  34         bool have_file = false; /* Conservatively return false if memory allocation failed. */
  35         const char *src;
  36
  37         if (!path)
  38                 return false;
  39
  40         /* Copy event_string replacing the ':' with '/'. */
  41         for (src = event_string, dst = path; *src; src++, dst++)
  42                 *dst = (*src == ':') ? '/' : *src;
  43         /* Add "/id\0". */
  44         memcpy(dst, "/id", 4);
  45
  46         dst = get_events_file(path);
  47         if (dst)
  48                 have_file = file_available(dst);
  49         free(dst);
  50         free(path);
  51         return have_file;
  52 }