+int refresh_lock(struct active_lock *lock)
+{
+ struct active_request_slot *slot;
+ char *if_header;
+ char timeout_header[25];
+ struct curl_slist *dav_headers = NULL;
+ int rc = 0;
+
+ lock->refreshing = 1;
+
+ if_header = xmalloc(strlen(lock->token) + 25);
+ sprintf(if_header, "If: (<opaquelocktoken:%s>)", lock->token);
+ sprintf(timeout_header, "Timeout: Second-%ld", lock->timeout);
+ dav_headers = curl_slist_append(dav_headers, if_header);
+ dav_headers = curl_slist_append(dav_headers, timeout_header);
+
+ slot = get_active_slot();
+ curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
+ curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_null);
+ curl_easy_setopt(slot->curl, CURLOPT_URL, lock->url);
+ curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, DAV_LOCK);
+ curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, dav_headers);
+
+ if (start_active_slot(slot)) {
+ run_active_slot(slot);
+ if (slot->curl_result != CURLE_OK) {
+ fprintf(stderr, "Got HTTP error %ld\n", slot->http_code);
+ } else {
+ lock->start_time = time(NULL);
+ rc = 1;
+ }
+ }
+
+ lock->refreshing = 0;
+ curl_slist_free_all(dav_headers);
+ free(if_header);
+
+ return rc;
+}
+