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authorDaniel Barkalow <barkalow@iabervon.org>2007-09-11 03:02:45 (GMT)
committerJunio C Hamano <gitster@pobox.com>2007-09-19 10:22:30 (GMT)
commit30ae764b1e11f10b5fca723a876a0f3de3ca11ab (patch)
treeb947d1e54e9bb87327e45395f28d4356821988c9 /http-walker.c
parentfbdeef948bbc085124f9634d5108940dce5fc688 (diff)
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Modularize commit-walker
This turns the extern functions to be provided by the backend into a struct of pointers, renames the functions to be more namespace-friendly, and updates http-fetch to this interface. It removes the unused include from http-push.c. It makes git-http-fetch a builtin (with the implementation a separate file, accessible directly). Signed-off-by: Daniel Barkalow <barkalow@iabervon.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'http-walker.c')
-rw-r--r--http-walker.c1035
1 files changed, 1035 insertions, 0 deletions
diff --git a/http-walker.c b/http-walker.c
new file mode 100644
index 0000000..444aebf
--- /dev/null
+++ b/http-walker.c
@@ -0,0 +1,1035 @@
+#include "cache.h"
+#include "commit.h"
+#include "pack.h"
+#include "walker.h"
+#include "http.h"
+
+#define PREV_BUF_SIZE 4096
+#define RANGE_HEADER_SIZE 30
+
+struct alt_base
+{
+ char *base;
+ int got_indices;
+ struct packed_git *packs;
+ struct alt_base *next;
+};
+
+enum object_request_state {
+ WAITING,
+ ABORTED,
+ ACTIVE,
+ COMPLETE,
+};
+
+struct object_request
+{
+ struct walker *walker;
+ unsigned char sha1[20];
+ struct alt_base *repo;
+ char *url;
+ char filename[PATH_MAX];
+ char tmpfile[PATH_MAX];
+ int local;
+ enum object_request_state state;
+ CURLcode curl_result;
+ char errorstr[CURL_ERROR_SIZE];
+ long http_code;
+ unsigned char real_sha1[20];
+ SHA_CTX c;
+ z_stream stream;
+ int zret;
+ int rename;
+ struct active_request_slot *slot;
+ struct object_request *next;
+};
+
+struct alternates_request {
+ struct walker *walker;
+ const char *base;
+ char *url;
+ struct buffer *buffer;
+ struct active_request_slot *slot;
+ int http_specific;
+};
+
+struct walker_data {
+ const char *url;
+ int got_alternates;
+ struct alt_base *alt;
+ struct curl_slist *no_pragma_header;
+};
+
+static struct object_request *object_queue_head;
+
+static size_t fwrite_sha1_file(void *ptr, size_t eltsize, size_t nmemb,
+ void *data)
+{
+ unsigned char expn[4096];
+ size_t size = eltsize * nmemb;
+ int posn = 0;
+ struct object_request *obj_req = (struct object_request *)data;
+ do {
+ ssize_t retval = xwrite(obj_req->local,
+ (char *) ptr + posn, size - posn);
+ if (retval < 0)
+ return posn;
+ posn += retval;
+ } while (posn < size);
+
+ obj_req->stream.avail_in = size;
+ obj_req->stream.next_in = ptr;
+ do {
+ obj_req->stream.next_out = expn;
+ obj_req->stream.avail_out = sizeof(expn);
+ obj_req->zret = inflate(&obj_req->stream, Z_SYNC_FLUSH);
+ SHA1_Update(&obj_req->c, expn,
+ sizeof(expn) - obj_req->stream.avail_out);
+ } while (obj_req->stream.avail_in && obj_req->zret == Z_OK);
+ data_received++;
+ return size;
+}
+
+static int missing__target(int code, int result)
+{
+ return /* file:// URL -- do we ever use one??? */
+ (result == CURLE_FILE_COULDNT_READ_FILE) ||
+ /* http:// and https:// URL */
+ (code == 404 && result == CURLE_HTTP_RETURNED_ERROR) ||
+ /* ftp:// URL */
+ (code == 550 && result == CURLE_FTP_COULDNT_RETR_FILE)
+ ;
+}
+
+#define missing_target(a) missing__target((a)->http_code, (a)->curl_result)
+
+static void fetch_alternates(struct walker *walker, const char *base);
+
+static void process_object_response(void *callback_data);
+
+static void start_object_request(struct walker *walker,
+ 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;
+ struct walker_data *data = walker->data;
+
+ 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) + 51);
+ obj_req->url = xmalloc(strlen(obj_req->repo->base) + 51);
+ strcpy(url, obj_req->repo->base);
+ posn = url + strlen(obj_req->repo->base);
+ strcpy(posn, "/objects/");
+ posn += 9;
+ 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 = xread(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, 0, SEEK_SET);
+ 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, data->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 (walker->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 (hashcmp(obj_req->sha1, obj_req->real_sha1)) {
+ unlink(obj_req->tmpfile);
+ return;
+ }
+ obj_req->rename =
+ move_temp_to_file(obj_req->tmpfile, obj_req->filename);
+
+ if (obj_req->rename == 0)
+ walker_say(obj_req->walker, "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;
+ struct walker *walker = obj_req->walker;
+ struct walker_data *data = walker->data;
+ struct alt_base *alt = data->alt;
+
+ 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 (missing_target(obj_req)) {
+ fetch_alternates(walker, 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(walker, obj_req);
+ return;
+ }
+ }
+
+ finish_object_request(obj_req);
+}
+
+static void release_object_request(struct object_request *obj_req)
+{
+ struct object_request *entry = object_queue_head;
+
+ if (obj_req->local != -1)
+ error("fd leakage in release: %d", obj_req->local);
+ if (obj_req == object_queue_head) {
+ object_queue_head = obj_req->next;
+ } else {
+ while (entry->next != NULL && entry->next != obj_req)
+ entry = entry->next;
+ if (entry->next == obj_req)
+ entry->next = entry->next->next;
+ }
+
+ free(obj_req->url);
+ free(obj_req);
+}
+
+#ifdef USE_CURL_MULTI
+static int fill_active_slot(struct walker *walker)
+{
+ struct object_request *obj_req;
+
+ for (obj_req = object_queue_head; obj_req; obj_req = obj_req->next) {
+ if (obj_req->state == WAITING) {
+ if (has_sha1_file(obj_req->sha1))
+ obj_req->state = COMPLETE;
+ else {
+ start_object_request(walker, obj_req);
+ return 1;
+ }
+ }
+ }
+ return 0;
+}
+#endif
+
+static void prefetch(struct walker *walker, unsigned char *sha1)
+{
+ struct object_request *newreq;
+ struct object_request *tail;
+ struct walker_data *data = walker->data;
+ char *filename = sha1_file_name(sha1);
+
+ newreq = xmalloc(sizeof(*newreq));
+ newreq->walker = walker;
+ hashcpy(newreq->sha1, sha1);
+ newreq->repo = data->alt;
+ newreq->url = NULL;
+ newreq->local = -1;
+ newreq->state = WAITING;
+ snprintf(newreq->filename, sizeof(newreq->filename), "%s", filename);
+ snprintf(newreq->tmpfile, sizeof(newreq->tmpfile),
+ "%s.temp", filename);
+ newreq->slot = NULL;
+ newreq->next = NULL;
+
+ if (object_queue_head == NULL) {
+ object_queue_head = newreq;
+ } else {
+ tail = object_queue_head;
+ while (tail->next != NULL) {
+ tail = tail->next;
+ }
+ tail->next = newreq;
+ }
+
+#ifdef USE_CURL_MULTI
+ fill_active_slots();
+ step_active_slots();
+#endif
+}
+
+static int fetch_index(struct walker *walker, struct alt_base *repo, unsigned char *sha1)
+{
+ char *hex = sha1_to_hex(sha1);
+ char *filename;
+ char *url;
+ char tmpfile[PATH_MAX];
+ long prev_posn = 0;
+ char range[RANGE_HEADER_SIZE];
+ struct curl_slist *range_header = NULL;
+ struct walker_data *data = walker->data;
+
+ FILE *indexfile;
+ struct active_request_slot *slot;
+ struct slot_results results;
+
+ if (has_pack_index(sha1))
+ return 0;
+
+ if (walker->get_verbosely)
+ fprintf(stderr, "Getting index for pack %s\n", hex);
+
+ url = xmalloc(strlen(repo->base) + 64);
+ sprintf(url, "%s/objects/pack/pack-%s.idx", repo->base, hex);
+
+ filename = sha1_pack_index_name(sha1);
+ snprintf(tmpfile, sizeof(tmpfile), "%s.temp", filename);
+ indexfile = fopen(tmpfile, "a");
+ if (!indexfile)
+ return error("Unable to open local file %s for pack index",
+ filename);
+
+ slot = get_active_slot();
+ slot->results = &results;
+ curl_easy_setopt(slot->curl, CURLOPT_FILE, indexfile);
+ curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
+ curl_easy_setopt(slot->curl, CURLOPT_URL, url);
+ curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, data->no_pragma_header);
+ slot->local = indexfile;
+
+ /* If there is data present from a previous transfer attempt,
+ resume where it left off */
+ prev_posn = ftell(indexfile);
+ if (prev_posn>0) {
+ if (walker->get_verbosely)
+ fprintf(stderr,
+ "Resuming fetch of index for pack %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);
+ }
+
+ if (start_active_slot(slot)) {
+ run_active_slot(slot);
+ if (results.curl_result != CURLE_OK) {
+ fclose(indexfile);
+ return error("Unable to get pack index %s\n%s", url,
+ curl_errorstr);
+ }
+ } else {
+ fclose(indexfile);
+ return error("Unable to start request");
+ }
+
+ fclose(indexfile);
+
+ return move_temp_to_file(tmpfile, filename);
+}
+
+static int setup_index(struct walker *walker, struct alt_base *repo, unsigned char *sha1)
+{
+ struct packed_git *new_pack;
+ if (has_pack_file(sha1))
+ return 0; /* don't list this as something we can get */
+
+ if (fetch_index(walker, repo, sha1))
+ return -1;
+
+ new_pack = parse_pack_index(sha1);
+ new_pack->next = repo->packs;
+ repo->packs = new_pack;
+ return 0;
+}
+
+static void process_alternates_response(void *callback_data)
+{
+ struct alternates_request *alt_req =
+ (struct alternates_request *)callback_data;
+ struct walker *walker = alt_req->walker;
+ struct walker_data *cdata = walker->data;
+ struct active_request_slot *slot = alt_req->slot;
+ struct alt_base *tail = cdata->alt;
+ const char *base = alt_req->base;
+ static const char null_byte = '\0';
+ char *data;
+ int i = 0;
+
+ if (alt_req->http_specific) {
+ if (slot->curl_result != CURLE_OK ||
+ !alt_req->buffer->posn) {
+
+ /* Try reusing the slot to get non-http alternates */
+ alt_req->http_specific = 0;
+ sprintf(alt_req->url, "%s/objects/info/alternates",
+ base);
+ curl_easy_setopt(slot->curl, CURLOPT_URL,
+ alt_req->url);
+ active_requests++;
+ slot->in_use = 1;
+ if (slot->finished != NULL)
+ (*slot->finished) = 0;
+ if (!start_active_slot(slot)) {
+ cdata->got_alternates = -1;
+ slot->in_use = 0;
+ if (slot->finished != NULL)
+ (*slot->finished) = 1;
+ }
+ return;
+ }
+ } else if (slot->curl_result != CURLE_OK) {
+ if (!missing_target(slot)) {
+ cdata->got_alternates = -1;
+ return;
+ }
+ }
+
+ fwrite_buffer(&null_byte, 1, 1, alt_req->buffer);
+ alt_req->buffer->posn--;
+ data = alt_req->buffer->buffer;
+
+ while (i < alt_req->buffer->posn) {
+ int posn = i;
+ while (posn < alt_req->buffer->posn && data[posn] != '\n')
+ posn++;
+ if (data[posn] == '\n') {
+ int okay = 0;
+ int serverlen = 0;
+ struct alt_base *newalt;
+ char *target = NULL;
+ if (data[i] == '/') {
+ /* This counts
+ * http://git.host/pub/scm/linux.git/
+ * -----------here^
+ * so memcpy(dst, base, serverlen) will
+ * copy up to "...git.host".
+ */
+ const char *colon_ss = strstr(base,"://");
+ if (colon_ss) {
+ serverlen = (strchr(colon_ss + 3, '/')
+ - base);
+ okay = 1;
+ }
+ } else if (!memcmp(data + i, "../", 3)) {
+ /* Relative URL; chop the corresponding
+ * number of subpath from base (and ../
+ * from data), and concatenate the result.
+ *
+ * The code first drops ../ from data, and
+ * then drops one ../ from data and one path
+ * from base. IOW, one extra ../ is dropped
+ * from data than path is dropped from base.
+ *
+ * This is not wrong. The alternate in
+ * http://git.host/pub/scm/linux.git/
+ * to borrow from
+ * http://git.host/pub/scm/linus.git/
+ * is ../../linus.git/objects/. You need
+ * two ../../ to borrow from your direct
+ * neighbour.
+ */
+ i += 3;
+ serverlen = strlen(base);
+ while (i + 2 < posn &&
+ !memcmp(data + i, "../", 3)) {
+ do {
+ serverlen--;
+ } while (serverlen &&
+ base[serverlen - 1] != '/');
+ i += 3;
+ }
+ /* If the server got removed, give up. */
+ okay = strchr(base, ':') - base + 3 <
+ serverlen;
+ } else if (alt_req->http_specific) {
+ char *colon = strchr(data + i, ':');
+ char *slash = strchr(data + i, '/');
+ if (colon && slash && colon < data + posn &&
+ slash < data + posn && colon < slash) {
+ okay = 1;
+ }
+ }
+ /* skip "objects\n" at end */
+ if (okay) {
+ target = xmalloc(serverlen + posn - i - 6);
+ memcpy(target, base, serverlen);
+ memcpy(target + serverlen, data + i,
+ posn - i - 7);
+ target[serverlen + posn - i - 7] = 0;
+ if (walker->get_verbosely)
+ fprintf(stderr,
+ "Also look at %s\n", target);
+ newalt = xmalloc(sizeof(*newalt));
+ newalt->next = NULL;
+ newalt->base = target;
+ newalt->got_indices = 0;
+ newalt->packs = NULL;
+
+ while (tail->next != NULL)
+ tail = tail->next;
+ tail->next = newalt;
+ }
+ }
+ i = posn + 1;
+ }
+
+ cdata->got_alternates = 1;
+}
+
+static void fetch_alternates(struct walker *walker, const char *base)
+{
+ struct buffer buffer;
+ char *url;
+ char *data;
+ struct active_request_slot *slot;
+ struct alternates_request alt_req;
+ struct walker_data *cdata = walker->data;
+
+ /* If another request has already started fetching alternates,
+ wait for them to arrive and return to processing this request's
+ curl message */
+#ifdef USE_CURL_MULTI
+ while (cdata->got_alternates == 0) {
+ step_active_slots();
+ }
+#endif
+
+ /* Nothing to do if they've already been fetched */
+ if (cdata->got_alternates == 1)
+ return;
+
+ /* Start the fetch */
+ cdata->got_alternates = 0;
+
+ data = xmalloc(4096);
+ buffer.size = 4096;
+ buffer.posn = 0;
+ buffer.buffer = data;
+
+ if (walker->get_verbosely)
+ fprintf(stderr, "Getting alternates list for %s\n", base);
+
+ url = xmalloc(strlen(base) + 31);
+ sprintf(url, "%s/objects/info/http-alternates", base);
+
+ /* Use a callback to process the result, since another request
+ may fail and need to have alternates loaded before continuing */
+ slot = get_active_slot();
+ slot->callback_func = process_alternates_response;
+ alt_req.walker = walker;
+ slot->callback_data = &alt_req;
+
+ curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
+ curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
+ curl_easy_setopt(slot->curl, CURLOPT_URL, url);
+
+ alt_req.base = base;
+ alt_req.url = url;
+ alt_req.buffer = &buffer;
+ alt_req.http_specific = 1;
+ alt_req.slot = slot;
+
+ if (start_active_slot(slot))
+ run_active_slot(slot);
+ else
+ cdata->got_alternates = -1;
+
+ free(data);
+ free(url);
+}
+
+static int fetch_indices(struct walker *walker, struct alt_base *repo)
+{
+ unsigned char sha1[20];
+ char *url;
+ struct buffer buffer;
+ char *data;
+ int i = 0;
+
+ struct active_request_slot *slot;
+ struct slot_results results;
+
+ if (repo->got_indices)
+ return 0;
+
+ data = xmalloc(4096);
+ buffer.size = 4096;
+ buffer.posn = 0;
+ buffer.buffer = data;
+
+ if (walker->get_verbosely)
+ fprintf(stderr, "Getting pack list for %s\n", repo->base);
+
+ url = xmalloc(strlen(repo->base) + 21);
+ sprintf(url, "%s/objects/info/packs", repo->base);
+
+ slot = get_active_slot();
+ slot->results = &results;
+ curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
+ curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
+ curl_easy_setopt(slot->curl, CURLOPT_URL, url);
+ curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
+ if (start_active_slot(slot)) {
+ run_active_slot(slot);
+ if (results.curl_result != CURLE_OK) {
+ if (missing_target(&results)) {
+ repo->got_indices = 1;
+ free(buffer.buffer);
+ return 0;
+ } else {
+ repo->got_indices = 0;
+ free(buffer.buffer);
+ return error("%s", curl_errorstr);
+ }
+ }
+ } else {
+ repo->got_indices = 0;
+ free(buffer.buffer);
+ return error("Unable to start request");
+ }
+
+ data = buffer.buffer;
+ while (i < buffer.posn) {
+ switch (data[i]) {
+ case 'P':
+ i++;
+ if (i + 52 <= buffer.posn &&
+ !prefixcmp(data + i, " pack-") &&
+ !prefixcmp(data + i + 46, ".pack\n")) {
+ get_sha1_hex(data + i + 6, sha1);
+ setup_index(walker, repo, sha1);
+ i += 51;
+ break;
+ }
+ default:
+ while (i < buffer.posn && data[i] != '\n')
+ i++;
+ }
+ i++;
+ }
+
+ free(buffer.buffer);
+ repo->got_indices = 1;
+ return 0;
+}
+
+static int fetch_pack(struct walker *walker, struct alt_base *repo, unsigned char *sha1)
+{
+ char *url;
+ struct packed_git *target;
+ struct packed_git **lst;
+ FILE *packfile;
+ char *filename;
+ char tmpfile[PATH_MAX];
+ int ret;
+ long prev_posn = 0;
+ char range[RANGE_HEADER_SIZE];
+ struct curl_slist *range_header = NULL;
+ struct walker_data *data = walker->data;
+
+ struct active_request_slot *slot;
+ struct slot_results results;
+
+ if (fetch_indices(walker, repo))
+ return -1;
+ target = find_sha1_pack(sha1, repo->packs);
+ if (!target)
+ return -1;
+
+ if (walker->get_verbosely) {
+ fprintf(stderr, "Getting pack %s\n",
+ sha1_to_hex(target->sha1));
+ fprintf(stderr, " which contains %s\n",
+ sha1_to_hex(sha1));
+ }
+
+ url = xmalloc(strlen(repo->base) + 65);
+ sprintf(url, "%s/objects/pack/pack-%s.pack",
+ repo->base, sha1_to_hex(target->sha1));
+
+ filename = sha1_pack_name(target->sha1);
+ snprintf(tmpfile, sizeof(tmpfile), "%s.temp", filename);
+ packfile = fopen(tmpfile, "a");
+ if (!packfile)
+ return error("Unable to open local file %s for pack",
+ filename);
+
+ slot = get_active_slot();
+ slot->results = &results;
+ curl_easy_setopt(slot->curl, CURLOPT_FILE, packfile);
+ curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
+ curl_easy_setopt(slot->curl, CURLOPT_URL, url);
+ curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, data->no_pragma_header);
+ slot->local = packfile;
+
+ /* If there is data present from a previous transfer attempt,
+ resume where it left off */
+ prev_posn = ftell(packfile);
+ if (prev_posn>0) {
+ if (walker->get_verbosely)
+ fprintf(stderr,
+ "Resuming fetch of pack %s at byte %ld\n",
+ sha1_to_hex(target->sha1), 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);
+ }
+
+ if (start_active_slot(slot)) {
+ run_active_slot(slot);
+ if (results.curl_result != CURLE_OK) {
+ fclose(packfile);
+ return error("Unable to get pack file %s\n%s", url,
+ curl_errorstr);
+ }
+ } else {
+ fclose(packfile);
+ return error("Unable to start request");
+ }
+
+ target->pack_size = ftell(packfile);
+ fclose(packfile);
+
+ ret = move_temp_to_file(tmpfile, filename);
+ if (ret)
+ return ret;
+
+ lst = &repo->packs;
+ while (*lst != target)
+ lst = &((*lst)->next);
+ *lst = (*lst)->next;
+
+ if (verify_pack(target, 0))
+ return -1;
+ install_packed_git(target);
+
+ return 0;
+}
+
+static void abort_object_request(struct object_request *obj_req)
+{
+ if (obj_req->local >= 0) {
+ close(obj_req->local);
+ obj_req->local = -1;
+ }
+ unlink(obj_req->tmpfile);
+ if (obj_req->slot) {
+ release_active_slot(obj_req->slot);
+ obj_req->slot = NULL;
+ }
+ release_object_request(obj_req);
+}
+
+static int fetch_object(struct walker *walker, struct alt_base *repo, unsigned char *sha1)
+{
+ char *hex = sha1_to_hex(sha1);
+ int ret = 0;
+ struct object_request *obj_req = object_queue_head;
+
+ while (obj_req != NULL && hashcmp(obj_req->sha1, sha1))
+ obj_req = obj_req->next;
+ if (obj_req == NULL)
+ return error("Couldn't find request for %s in the queue", hex);
+
+ if (has_sha1_file(obj_req->sha1)) {
+ abort_object_request(obj_req);
+ return 0;
+ }
+
+#ifdef USE_CURL_MULTI
+ while (obj_req->state == WAITING) {
+ step_active_slots();
+ }
+#else
+ start_object_request(walker, obj_req);
+#endif
+
+ while (obj_req->state == ACTIVE) {
+ run_active_slot(obj_req->slot);
+ }
+ if (obj_req->local != -1) {
+ close(obj_req->local); obj_req->local = -1;
+ }
+
+ if (obj_req->state == ABORTED) {
+ ret = error("Request for %s aborted", hex);
+ } else if (obj_req->curl_result != CURLE_OK &&
+ obj_req->http_code != 416) {
+ if (missing_target(obj_req))
+ ret = -1; /* Be silent, it is probably in a pack. */
+ else
+ ret = error("%s (curl_result = %d, http_code = %ld, sha1 = %s)",
+ obj_req->errorstr, obj_req->curl_result,
+ obj_req->http_code, hex);
+ } else if (obj_req->zret != Z_STREAM_END) {
+ walker->corrupt_object_found++;
+ ret = error("File %s (%s) corrupt", hex, obj_req->url);
+ } else if (hashcmp(obj_req->sha1, obj_req->real_sha1)) {
+ ret = error("File %s has bad hash", hex);
+ } else if (obj_req->rename < 0) {
+ ret = error("unable to write sha1 filename %s",
+ obj_req->filename);
+ }
+
+ release_object_request(obj_req);
+ return ret;
+}
+
+static int fetch(struct walker *walker, unsigned char *sha1)
+{
+ struct walker_data *data = walker->data;
+ struct alt_base *altbase = data->alt;
+
+ if (!fetch_object(walker, altbase, sha1))
+ return 0;
+ while (altbase) {
+ if (!fetch_pack(walker, altbase, sha1))
+ return 0;
+ fetch_alternates(walker, data->alt->base);
+ altbase = altbase->next;
+ }
+ return error("Unable to find %s under %s", sha1_to_hex(sha1),
+ data->alt->base);
+}
+
+static inline int needs_quote(int ch)
+{
+ if (((ch >= 'A') && (ch <= 'Z'))
+ || ((ch >= 'a') && (ch <= 'z'))
+ || ((ch >= '0') && (ch <= '9'))
+ || (ch == '/')
+ || (ch == '-')
+ || (ch == '.'))
+ return 0;
+ return 1;
+}
+
+static inline int hex(int v)
+{
+ if (v < 10) return '0' + v;
+ else return 'A' + v - 10;
+}
+
+static char *quote_ref_url(const char *base, const char *ref)
+{
+ const char *cp;
+ char *dp, *qref;
+ int len, baselen, ch;
+
+ baselen = strlen(base);
+ len = baselen + 7; /* "/refs/" + NUL */
+ for (cp = ref; (ch = *cp) != 0; cp++, len++)
+ if (needs_quote(ch))
+ len += 2; /* extra two hex plus replacement % */
+ qref = xmalloc(len);
+ memcpy(qref, base, baselen);
+ memcpy(qref + baselen, "/refs/", 6);
+ for (cp = ref, dp = qref + baselen + 6; (ch = *cp) != 0; cp++) {
+ if (needs_quote(ch)) {
+ *dp++ = '%';
+ *dp++ = hex((ch >> 4) & 0xF);
+ *dp++ = hex(ch & 0xF);
+ }
+ else
+ *dp++ = ch;
+ }
+ *dp = 0;
+
+ return qref;
+}
+
+static int fetch_ref(struct walker *walker, char *ref, unsigned char *sha1)
+{
+ char *url;
+ char hex[42];
+ struct buffer buffer;
+ struct walker_data *data = walker->data;
+ const char *base = data->alt->base;
+ struct active_request_slot *slot;
+ struct slot_results results;
+ buffer.size = 41;
+ buffer.posn = 0;
+ buffer.buffer = hex;
+ hex[41] = '\0';
+
+ url = quote_ref_url(base, ref);
+ slot = get_active_slot();
+ slot->results = &results;
+ curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
+ curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
+ curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
+ curl_easy_setopt(slot->curl, CURLOPT_URL, url);
+ if (start_active_slot(slot)) {
+ run_active_slot(slot);
+ if (results.curl_result != CURLE_OK)
+ return error("Couldn't get %s for %s\n%s",
+ url, ref, curl_errorstr);
+ } else {
+ return error("Unable to start request");
+ }
+
+ hex[40] = '\0';
+ get_sha1_hex(hex, sha1);
+ return 0;
+}
+
+static void cleanup(struct walker *walker)
+{
+ struct walker_data *data = walker->data;
+ http_cleanup();
+
+ curl_slist_free_all(data->no_pragma_header);
+}
+
+struct walker *get_http_walker(const char *url)
+{
+ char *s;
+ struct walker_data *data = xmalloc(sizeof(struct walker_data));
+ struct walker *walker = xmalloc(sizeof(struct walker));
+
+ http_init();
+
+ data->no_pragma_header = curl_slist_append(NULL, "Pragma:");
+
+ data->alt = xmalloc(sizeof(*data->alt));
+ data->alt->base = xmalloc(strlen(url) + 1);
+ strcpy(data->alt->base, url);
+ for (s = data->alt->base + strlen(data->alt->base) - 1; *s == '/'; --s)
+ *s = 0;
+
+ data->alt->got_indices = 0;
+ data->alt->packs = NULL;
+ data->alt->next = NULL;
+ data->got_alternates = -1;
+
+ walker->corrupt_object_found = 0;
+ walker->fetch = fetch;
+ walker->fetch_ref = fetch_ref;
+ walker->prefetch = prefetch;
+ walker->cleanup = cleanup;
+ walker->data = data;
+
+#ifdef USE_CURL_MULTI
+ add_fill_function(walker, (int (*)(void *)) fill_active_slot);
+#endif
+
+ return walker;
+}