-out:
- *out = '\0';
- *len = out - first;
- return ret;
-}
-
-/*
- * Computes the length of s when encoded with three-digit octal escape sequences
- * for the characters in chars.
- */
-static size_t octal_encoded_length(const char *s, const char *chars)
-{
- size_t len = strlen(s);
- while ((s = strpbrk(s, chars)) != NULL) {
- len += 3;
- s++;
- }
-
- return len;
-}
-
-enum {
- OUTCOME_NOTHING_MOUNTED,
- OUTCOME_TMPFS_MOUNT,
- OUTCOME_NON_TMPFS_MOUNT,
-};
-
-/* Read a line of /proc/mounts data looking for a tmpfs mount at "path". */
-static int read_mount(int fd, char *buf, size_t bufsize, const char *path,
- int *outcome)
-{
- int found;
- int match;
- char *space;
- size_t len;
-
- enum {
- MATCH_NONE,
- MATCH_EXACT,
- MATCH_PARENT,
- };
-
- found = next(fd, buf, bufsize, ' ');
- if (found != 1)
- return found;
-
- /*
- * If there's no following space in the buffer, then this path is
- * truncated, so it can't be the one we're looking for.
- */
- space = strchr(buf, ' ');
- if (space) {
- match = MATCH_NONE;
- if (!decode_path(buf, buf, &len)) {
- if (!strcmp(buf, path))
- match = MATCH_EXACT;
- else if (!strncmp(buf, path, len)
- && (path[len] == '/' || !strcmp(buf, "/")))
- match = MATCH_PARENT;
- }
-
- found = pop(fd, buf, bufsize, space - buf + 1);
- if (found != 1)
- return found;
-
- switch (match) {
- case MATCH_EXACT:
- if (!strncmp(buf, "tmpfs", strlen("tmpfs")))
- *outcome = OUTCOME_TMPFS_MOUNT;
- else
- *outcome = OUTCOME_NON_TMPFS_MOUNT;
- break;
-
- case MATCH_PARENT:
- /* This mount obscures any previous ones. */
- *outcome = OUTCOME_NOTHING_MOUNTED;
- break;
- }