diff options
| -rw-r--r-- | tools/lib/api/fs/cgroup.c | 70 |
1 files changed, 45 insertions, 25 deletions
diff --git a/tools/lib/api/fs/cgroup.c b/tools/lib/api/fs/cgroup.c index 813236d8ca48..262a4229e293 100644 --- a/tools/lib/api/fs/cgroup.c +++ b/tools/lib/api/fs/cgroup.c @@ -11,9 +11,10 @@ int cgroupfs_find_mountpoint(char *buf, size_t maxlen, const char *subsys) { FILE *fp; - char mountpoint[PATH_MAX + 1], tokens[PATH_MAX + 1], type[PATH_MAX + 1]; - char path_v2[PATH_MAX + 1]; - char *token, *saved_ptr = NULL; + char *line = NULL; + size_t len = 0; + char *p, *path; + char mountpoint[PATH_MAX]; fp = fopen("/proc/mounts", "r"); if (!fp) @@ -25,38 +26,57 @@ int cgroupfs_find_mountpoint(char *buf, size_t maxlen, const char *subsys) * the given subsystem. If we found v1, just use it. If not we can * use v2 path as a fallback. */ - path_v2[0] = '\0'; + mountpoint[0] = '\0'; - while (fscanf(fp, "%*s %"__stringify(PATH_MAX)"s %"__stringify(PATH_MAX)"s %" - __stringify(PATH_MAX)"s %*d %*d\n", - mountpoint, type, tokens) == 3) { + /* + * The /proc/mounts has the follow format: + * + * <devname> <mount point> <fs type> <options> ... + * + */ + while (getline(&line, &len, fp) != -1) { + /* skip devname */ + p = strchr(line, ' '); + if (p == NULL) + continue; - if (!strcmp(type, "cgroup")) { + /* save the mount point */ + path = ++p; + p = strchr(p, ' '); + if (p == NULL) + continue; - token = strtok_r(tokens, ",", &saved_ptr); + *p++ = '\0'; - while (token != NULL) { - if (subsys && !strcmp(token, subsys)) { - /* found */ - fclose(fp); + /* check filesystem type */ + if (strncmp(p, "cgroup", 6)) + continue; - if (strlen(mountpoint) < maxlen) { - strcpy(buf, mountpoint); - return 0; - } - return -1; - } - token = strtok_r(NULL, ",", &saved_ptr); - } + if (p[6] == '2') { + /* save cgroup v2 path */ + strcpy(mountpoint, path); + continue; } - if (!strcmp(type, "cgroup2")) - strcpy(path_v2, mountpoint); + /* now we have cgroup v1, check the options for subsystem */ + p += 7; + + p = strstr(p, subsys); + if (p == NULL) + continue; + + /* sanity check: it should be separated by a space or a comma */ + if (!strchr(" ,", p[-1]) || !strchr(" ,", p[strlen(subsys)])) + continue; + + strcpy(mountpoint, path); + break; } + free(line); fclose(fp); - if (path_v2[0] && strlen(path_v2) < maxlen) { - strcpy(buf, path_v2); + if (mountpoint[0] && strlen(mountpoint) < maxlen) { + strcpy(buf, mountpoint); return 0; } return -1; |