+/*
+ * Make sure the output path is valid for a single trace: either it does
+ * not exists or it is empty.
+ *
+ * Return 0 if the path is valid, -1 otherwise.
+ */
+static
+bool valid_single_trace_path(const char *path)
+{
+ GError *error = NULL;
+ GDir *dir = NULL;
+ int ret = 0;
+
+ dir = g_dir_open(path, 0, &error);
+
+ /* Non-existent directory. */
+ if (!dir) {
+ /* For any other error, return an error */
+ if (error->code != G_FILE_ERROR_NOENT) {
+ ret = -1;
+ }
+ goto end;
+ }
+
+ /* g_dir_read_name skips "." and "..", error out on first result */
+ while (g_dir_read_name(dir) != NULL) {
+ ret = -1;
+ break;
+ }
+
+end:
+ if (dir) {
+ g_dir_close(dir);
+ }
+ if (error) {
+ g_error_free(error);
+ }
+
+ return ret;
+}
+
+static
+int make_trace_path(struct writer_component *writer_component,
+ const bt_trace *trace, char *trace_path)
+{
+ int ret;
+ const char *trace_name;
+
+ if (writer_component->single_trace) {
+ trace_name = "\0";
+ } else {
+ trace_name = bt_trace_get_name(trace);
+ if (!trace_name) {
+ trace_name = writer_component->trace_name_base->str;
+ }
+ }
+
+ /* Sanitize the trace name. */
+ if (strlen(trace_name) == 2 && !strcmp(trace_name, "..")) {
+ BT_LOGE_STR("Trace name cannot be \"..\".");
+ goto error;
+ }
+
+ if (strstr(trace_name, "../")) {
+ BT_LOGE_STR("Trace name cannot contain \"../\".");
+ goto error;
+
+ }
+
+ snprintf(trace_path, PATH_MAX, "%s" G_DIR_SEPARATOR_S "%s",
+ writer_component->base_path->str,
+ trace_name);
+ /*
+ * Append a suffix if the trace_path exists and we are not in
+ * single-trace mode.
+ */
+ if (writer_component->single_trace) {
+ if (valid_single_trace_path(trace_path) != 0) {
+ BT_LOGE_STR("Invalid output directory.");
+ goto error;
+ }
+ } else {
+ if (g_file_test(trace_path, G_FILE_TEST_EXISTS)) {
+ int i = 0;
+
+ do {
+ snprintf(trace_path, PATH_MAX, "%s" G_DIR_SEPARATOR_S "%s-%d",
+ writer_component->base_path->str,
+ trace_name, ++i);
+ } while (g_file_test(trace_path, G_FILE_TEST_EXISTS) && i < INT_MAX);
+ if (i == INT_MAX) {
+ BT_LOGE_STR("Unable to find a unique trace path.");
+ goto error;
+ }
+ }
+ }
+
+ ret = 0;
+ goto end;
+
+error:
+ ret = -1;
+end:
+ return ret;
+}
+