Function join_path_components

src/port/path.c:217–241

* join_path_components - join two path components, inserting a slash * * We omit the slash if either given component is empty. * * ret_path is the output area (must be of size MAXPGPATH) * * ret_path can be the same as head, but not the same as tail. */

 * ret_path can be the same as head, but not the same as tail.
 */
void
join_path_components(char *ret_path,
					 const char *head, const char *tail)
{
	if (ret_path != head)
		strlcpy(ret_path, head, MAXPGPATH);

	/*
	 * Remove any leading "." in the tail component.
	 *
	 * Note: we used to try to remove ".." as well, but that's tricky to get
	 * right; now we just leave it to be done by canonicalize_path() later.
	 */
	while (tail[0] == '.' && IS_DIR_SEP(tail[1]))
		tail += 2;

	if (*tail)
	{
		/* only separate with slash if head wasn't empty */
		snprintf(ret_path + strlen(ret_path), MAXPGPATH - strlen(ret_path),
				 "%s%s",
				 (*(skip_drive(head)) != '\0') ? "/" : "",
				 tail);
	}
}


/*