Added a result system to keep better track of errors

src/entry.c

@@ -20,4 +20,31 @@ bool is_entry_id_valid(const char* entry_id) {
 			return false;
 
 	return true;
-}
+}
+
+Result get_entry_path(const char* entry_id, char** out_path) {
+	*out_path = NULL;
+
+	if (!is_entry_id_valid(entry_id))
+		return FAILURE;
+
+	return format(out_path, "%s/%s", ENTRY_POOL_DIR, entry_id);
+}
+
+Result entry_exists(const char* entry_id, bool* out_exists) {
+	*out_exists = false;
+
+	char* path;
+	Result result = get_entry_path(entry_id, &path);
+	if (result != SUCCESS)
+		return result;
+
+	struct stat st;
+	bool exists = stat(path, &st) == 0 && S_ISDIR(st.st_mode);
+
+	free(path);
+
+	*out_exists = exists;
+
+	return SUCCESS;
+}