+static void fetch_alternates(char *base);
+
+static void process_object_response(void *callback_data);
+
+static void start_object_request(struct object_request *obj_req)
+{
+ char *hex = sha1_to_hex(obj_req->sha1);
+ char prevfile[PATH_MAX];
+ char *url;
+ char *posn;
+ int prevlocal;
+ unsigned char prev_buf[PREV_BUF_SIZE];
+ ssize_t prev_read = 0;
+ long prev_posn = 0;
+ char range[RANGE_HEADER_SIZE];
+ struct curl_slist *range_header = NULL;
+ struct active_request_slot *slot;
+
+ snprintf(prevfile, sizeof(prevfile), "%s.prev", obj_req->filename);
+ unlink(prevfile);
+ rename(obj_req->tmpfile, prevfile);
+ unlink(obj_req->tmpfile);
+
+ if (obj_req->local != -1)
+ error("fd leakage in start: %d", obj_req->local);
+ obj_req->local = open(obj_req->tmpfile,
+ O_WRONLY | O_CREAT | O_EXCL, 0666);
+ /* This could have failed due to the "lazy directory creation";
+ * try to mkdir the last path component.
+ */
+ if (obj_req->local < 0 && errno == ENOENT) {
+ char *dir = strrchr(obj_req->tmpfile, '/');
+ if (dir) {
+ *dir = 0;
+ mkdir(obj_req->tmpfile, 0777);
+ *dir = '/';
+ }
+ obj_req->local = open(obj_req->tmpfile,
+ O_WRONLY | O_CREAT | O_EXCL, 0666);
+ }
+
+ if (obj_req->local < 0) {
+ obj_req->state = ABORTED;
+ error("Couldn't create temporary file %s for %s: %s",
+ obj_req->tmpfile, obj_req->filename, strerror(errno));
+ return;
+ }
+
+ memset(&obj_req->stream, 0, sizeof(obj_req->stream));
+
+ inflateInit(&obj_req->stream);
+
+ SHA1_Init(&obj_req->c);
+
+ url = xmalloc(strlen(obj_req->repo->base) + 50);
+ obj_req->url = xmalloc(strlen(obj_req->repo->base) + 50);
+ strcpy(url, obj_req->repo->base);
+ posn = url + strlen(obj_req->repo->base);
+ strcpy(posn, "objects/");
+ posn += 8;
+ memcpy(posn, hex, 2);
+ posn += 2;
+ *(posn++) = '/';
+ strcpy(posn, hex + 2);
+ strcpy(obj_req->url, url);
+
+ /* If a previous temp file is present, process what was already
+ fetched. */
+ prevlocal = open(prevfile, O_RDONLY);
+ if (prevlocal != -1) {
+ do {
+ prev_read = read(prevlocal, prev_buf, PREV_BUF_SIZE);
+ if (prev_read>0) {
+ if (fwrite_sha1_file(prev_buf,
+ 1,
+ prev_read,
+ obj_req) == prev_read) {
+ prev_posn += prev_read;
+ } else {
+ prev_read = -1;
+ }
+ }
+ } while (prev_read > 0);
+ close(prevlocal);
+ }
+ unlink(prevfile);
+
+ /* Reset inflate/SHA1 if there was an error reading the previous temp
+ file; also rewind to the beginning of the local file. */
+ if (prev_read == -1) {
+ memset(&obj_req->stream, 0, sizeof(obj_req->stream));
+ inflateInit(&obj_req->stream);
+ SHA1_Init(&obj_req->c);
+ if (prev_posn>0) {
+ prev_posn = 0;
+ lseek(obj_req->local, SEEK_SET, 0);
+ ftruncate(obj_req->local, 0);
+ }
+ }
+
+ slot = get_active_slot();
+ slot->callback_func = process_object_response;
+ slot->callback_data = obj_req;
+ obj_req->slot = slot;
+
+ curl_easy_setopt(slot->curl, CURLOPT_FILE, obj_req);
+ curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
+ curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, obj_req->errorstr);
+ curl_easy_setopt(slot->curl, CURLOPT_URL, url);
+ curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
+
+ /* If we have successfully processed data from a previous fetch
+ attempt, only fetch the data we don't already have. */
+ if (prev_posn>0) {
+ if (get_verbosely)
+ fprintf(stderr,
+ "Resuming fetch of object %s at byte %ld\n",
+ hex, prev_posn);
+ sprintf(range, "Range: bytes=%ld-", prev_posn);
+ range_header = curl_slist_append(range_header, range);
+ curl_easy_setopt(slot->curl,
+ CURLOPT_HTTPHEADER, range_header);
+ }
+
+ /* Try to get the request started, abort the request on error */
+ obj_req->state = ACTIVE;
+ if (!start_active_slot(slot)) {
+ obj_req->state = ABORTED;
+ obj_req->slot = NULL;
+ close(obj_req->local); obj_req->local = -1;
+ free(obj_req->url);
+ return;
+ }
+}
+
+static void finish_object_request(struct object_request *obj_req)
+{
+ struct stat st;
+
+ fchmod(obj_req->local, 0444);
+ close(obj_req->local); obj_req->local = -1;
+
+ if (obj_req->http_code == 416) {
+ fprintf(stderr, "Warning: requested range invalid; we may already have all the data.\n");
+ } else if (obj_req->curl_result != CURLE_OK) {
+ if (stat(obj_req->tmpfile, &st) == 0)
+ if (st.st_size == 0)
+ unlink(obj_req->tmpfile);
+ return;
+ }
+
+ inflateEnd(&obj_req->stream);
+ SHA1_Final(obj_req->real_sha1, &obj_req->c);
+ if (obj_req->zret != Z_STREAM_END) {
+ unlink(obj_req->tmpfile);
+ return;
+ }
+ if (memcmp(obj_req->sha1, obj_req->real_sha1, 20)) {
+ unlink(obj_req->tmpfile);
+ return;
+ }
+ obj_req->rename =
+ move_temp_to_file(obj_req->tmpfile, obj_req->filename);
+
+ if (obj_req->rename == 0)
+ pull_say("got %s\n", sha1_to_hex(obj_req->sha1));
+}
+
+static void process_object_response(void *callback_data)
+{
+ struct object_request *obj_req =
+ (struct object_request *)callback_data;
+
+ obj_req->curl_result = obj_req->slot->curl_result;
+ obj_req->http_code = obj_req->slot->http_code;
+ obj_req->slot = NULL;
+ obj_req->state = COMPLETE;
+
+ /* Use alternates if necessary */
+ if (obj_req->http_code == 404 ||
+ obj_req->curl_result == CURLE_FILE_COULDNT_READ_FILE) {
+ fetch_alternates(alt->base);
+ if (obj_req->repo->next != NULL) {
+ obj_req->repo =
+ obj_req->repo->next;
+ close(obj_req->local);
+ obj_req->local = -1;
+ start_object_request(obj_req);
+ return;
+ }
+ }
+
+ finish_object_request(obj_req);
+}
+
+static void release_object_request(struct object_request *obj_req)