-
-/*
- * Return the realpath(3) of the path even if the last directory token does not
- * exist. For example, with /tmp/test1/test2, if test2/ does not exist but the
- * /tmp/test1 does, the real path is returned. In normal time, realpath(3)
- * fails if the end point directory does not exist.
- */
-LTTNG_HIDDEN
-char *utils_expand_path(const char *path)
-{
- const char *end_path = NULL;
- char *next, *cut_path = NULL, *expanded_path = NULL;
-
- /* Safety net */
- if (path == NULL) {
- goto error;
- }
-
- /* Allocate memory for the expanded path */
- expanded_path = zmalloc(PATH_MAX);
- if (expanded_path == NULL) {
- PERROR("zmalloc expand path");
- goto error;
- }
-
- /* If given path is already absolute */
- if (*path == '/') {
- strncpy(expanded_path, path, PATH_MAX);
- /* Else, we have some work to do */
- } else {
- /* Pointer to the last char of the path */
- const char *last_char = path + strlen(path) - 1;
-
- end_path = path;
-
- /* Split part that will be resolved by realpath (relative path from
- * current directory using ./ or ../ only) and part that could not
- * (directory names)
- */
- while ((next = strpbrk(end_path, "/")) && (next != last_char)) {
- end_path = next + 1;
- if (strncmp(end_path, "./", 2) != 0 &&
- strncmp(end_path, "../", 3) != 0) {
- break;
- }
- }
-
- /* If this is the end of the string, and we still can resolve it */
- if (strncmp(end_path, "..\0", 3) == 0 ||
- strncmp(end_path, ".\0", 2) == 0) {
- end_path += strlen(end_path);
- }
-
- /* If the end part is the whole path, we are in the current dir */
- if (end_path == path) {
- cut_path = strdup(".");
- /* Else, cut the resolvable part from original path */
- } else {
- cut_path = strndup(path, end_path - path);
- }
-
- /* Resolve the canonical path of the first part of the path */
- expanded_path = realpath((char *)cut_path, expanded_path);
- if (expanded_path == NULL) {
- switch (errno) {
- case ENOENT:
- ERR("%s: No such file or directory", cut_path);
- break;
- default:
- PERROR("realpath utils expand path");
- break;
- }
- goto error;
- }
-
- /* Add end part to expanded path if not empty */
- if (*end_path != 0) {
- strncat(expanded_path, "/", PATH_MAX - strlen(expanded_path) - 1);
- strncat(expanded_path, end_path,
- PATH_MAX - strlen(expanded_path) - 1);
- }
- }
-
- /* Resolve the internal './' and '../' strings */
- next = utils_resolve_relative(expanded_path);
- if (next == NULL) {
- goto error;
- }
-
- free(expanded_path);
- free(cut_path);
- return next;
-
-error:
- free(expanded_path);
- free(cut_path);
- return NULL;
-}
-