doc: describe git svn init --ignore-refs
[git/git-svn.git] / http-walker.c
blobee049cb13df6ed6a64b1980004100a5dd55dde51
1 #include "cache.h"
2 #include "commit.h"
3 #include "walker.h"
4 #include "http.h"
5 #include "list.h"
6 #include "transport.h"
8 struct alt_base {
9 char *base;
10 int got_indices;
11 struct packed_git *packs;
12 struct alt_base *next;
15 enum object_request_state {
16 WAITING,
17 ABORTED,
18 ACTIVE,
19 COMPLETE
22 struct object_request {
23 struct walker *walker;
24 unsigned char sha1[20];
25 struct alt_base *repo;
26 enum object_request_state state;
27 struct http_object_request *req;
28 struct list_head node;
31 struct alternates_request {
32 struct walker *walker;
33 const char *base;
34 struct strbuf *url;
35 struct strbuf *buffer;
36 struct active_request_slot *slot;
37 int http_specific;
40 struct walker_data {
41 const char *url;
42 int got_alternates;
43 struct alt_base *alt;
46 static LIST_HEAD(object_queue_head);
48 static void fetch_alternates(struct walker *walker, const char *base);
50 static void process_object_response(void *callback_data);
52 static void start_object_request(struct walker *walker,
53 struct object_request *obj_req)
55 struct active_request_slot *slot;
56 struct http_object_request *req;
58 req = new_http_object_request(obj_req->repo->base, obj_req->sha1);
59 if (req == NULL) {
60 obj_req->state = ABORTED;
61 return;
63 obj_req->req = req;
65 slot = req->slot;
66 slot->callback_func = process_object_response;
67 slot->callback_data = obj_req;
69 /* Try to get the request started, abort the request on error */
70 obj_req->state = ACTIVE;
71 if (!start_active_slot(slot)) {
72 obj_req->state = ABORTED;
73 release_http_object_request(req);
74 return;
78 static void finish_object_request(struct object_request *obj_req)
80 if (finish_http_object_request(obj_req->req))
81 return;
83 if (obj_req->req->rename == 0)
84 walker_say(obj_req->walker, "got %s\n", sha1_to_hex(obj_req->sha1));
87 static void process_object_response(void *callback_data)
89 struct object_request *obj_req =
90 (struct object_request *)callback_data;
91 struct walker *walker = obj_req->walker;
92 struct walker_data *data = walker->data;
93 struct alt_base *alt = data->alt;
95 process_http_object_request(obj_req->req);
96 obj_req->state = COMPLETE;
98 /* Use alternates if necessary */
99 if (missing_target(obj_req->req)) {
100 fetch_alternates(walker, alt->base);
101 if (obj_req->repo->next != NULL) {
102 obj_req->repo =
103 obj_req->repo->next;
104 release_http_object_request(obj_req->req);
105 start_object_request(walker, obj_req);
106 return;
110 finish_object_request(obj_req);
113 static void release_object_request(struct object_request *obj_req)
115 if (obj_req->req !=NULL && obj_req->req->localfile != -1)
116 error("fd leakage in release: %d", obj_req->req->localfile);
118 list_del(&obj_req->node);
119 free(obj_req);
122 #ifdef USE_CURL_MULTI
123 static int fill_active_slot(struct walker *walker)
125 struct object_request *obj_req;
126 struct list_head *pos, *tmp, *head = &object_queue_head;
128 list_for_each_safe(pos, tmp, head) {
129 obj_req = list_entry(pos, struct object_request, node);
130 if (obj_req->state == WAITING) {
131 if (has_sha1_file(obj_req->sha1))
132 obj_req->state = COMPLETE;
133 else {
134 start_object_request(walker, obj_req);
135 return 1;
139 return 0;
141 #endif
143 static void prefetch(struct walker *walker, unsigned char *sha1)
145 struct object_request *newreq;
146 struct walker_data *data = walker->data;
148 newreq = xmalloc(sizeof(*newreq));
149 newreq->walker = walker;
150 hashcpy(newreq->sha1, sha1);
151 newreq->repo = data->alt;
152 newreq->state = WAITING;
153 newreq->req = NULL;
155 http_is_verbose = walker->get_verbosely;
156 list_add_tail(&newreq->node, &object_queue_head);
158 #ifdef USE_CURL_MULTI
159 fill_active_slots();
160 step_active_slots();
161 #endif
164 static int is_alternate_allowed(const char *url)
166 const char *protocols[] = {
167 "http", "https", "ftp", "ftps"
169 int i;
171 if (http_follow_config != HTTP_FOLLOW_ALWAYS) {
172 warning("alternate disabled by http.followRedirects: %s", url);
173 return 0;
176 for (i = 0; i < ARRAY_SIZE(protocols); i++) {
177 const char *end;
178 if (skip_prefix(url, protocols[i], &end) &&
179 starts_with(end, "://"))
180 break;
183 if (i >= ARRAY_SIZE(protocols)) {
184 warning("ignoring alternate with unknown protocol: %s", url);
185 return 0;
187 if (!is_transport_allowed(protocols[i], 0)) {
188 warning("ignoring alternate with restricted protocol: %s", url);
189 return 0;
192 return 1;
195 static void process_alternates_response(void *callback_data)
197 struct alternates_request *alt_req =
198 (struct alternates_request *)callback_data;
199 struct walker *walker = alt_req->walker;
200 struct walker_data *cdata = walker->data;
201 struct active_request_slot *slot = alt_req->slot;
202 struct alt_base *tail = cdata->alt;
203 const char *base = alt_req->base;
204 const char null_byte = '\0';
205 char *data;
206 int i = 0;
208 if (alt_req->http_specific) {
209 if (slot->curl_result != CURLE_OK ||
210 !alt_req->buffer->len) {
212 /* Try reusing the slot to get non-http alternates */
213 alt_req->http_specific = 0;
214 strbuf_reset(alt_req->url);
215 strbuf_addf(alt_req->url, "%s/objects/info/alternates",
216 base);
217 curl_easy_setopt(slot->curl, CURLOPT_URL,
218 alt_req->url->buf);
219 active_requests++;
220 slot->in_use = 1;
221 if (slot->finished != NULL)
222 (*slot->finished) = 0;
223 if (!start_active_slot(slot)) {
224 cdata->got_alternates = -1;
225 slot->in_use = 0;
226 if (slot->finished != NULL)
227 (*slot->finished) = 1;
229 return;
231 } else if (slot->curl_result != CURLE_OK) {
232 if (!missing_target(slot)) {
233 cdata->got_alternates = -1;
234 return;
238 fwrite_buffer((char *)&null_byte, 1, 1, alt_req->buffer);
239 alt_req->buffer->len--;
240 data = alt_req->buffer->buf;
242 while (i < alt_req->buffer->len) {
243 int posn = i;
244 while (posn < alt_req->buffer->len && data[posn] != '\n')
245 posn++;
246 if (data[posn] == '\n') {
247 int okay = 0;
248 int serverlen = 0;
249 struct alt_base *newalt;
250 if (data[i] == '/') {
252 * This counts
253 * http://git.host/pub/scm/linux.git/
254 * -----------here^
255 * so memcpy(dst, base, serverlen) will
256 * copy up to "...git.host".
258 const char *colon_ss = strstr(base,"://");
259 if (colon_ss) {
260 serverlen = (strchr(colon_ss + 3, '/')
261 - base);
262 okay = 1;
264 } else if (!memcmp(data + i, "../", 3)) {
266 * Relative URL; chop the corresponding
267 * number of subpath from base (and ../
268 * from data), and concatenate the result.
270 * The code first drops ../ from data, and
271 * then drops one ../ from data and one path
272 * from base. IOW, one extra ../ is dropped
273 * from data than path is dropped from base.
275 * This is not wrong. The alternate in
276 * http://git.host/pub/scm/linux.git/
277 * to borrow from
278 * http://git.host/pub/scm/linus.git/
279 * is ../../linus.git/objects/. You need
280 * two ../../ to borrow from your direct
281 * neighbour.
283 i += 3;
284 serverlen = strlen(base);
285 while (i + 2 < posn &&
286 !memcmp(data + i, "../", 3)) {
287 do {
288 serverlen--;
289 } while (serverlen &&
290 base[serverlen - 1] != '/');
291 i += 3;
293 /* If the server got removed, give up. */
294 okay = strchr(base, ':') - base + 3 <
295 serverlen;
296 } else if (alt_req->http_specific) {
297 char *colon = strchr(data + i, ':');
298 char *slash = strchr(data + i, '/');
299 if (colon && slash && colon < data + posn &&
300 slash < data + posn && colon < slash) {
301 okay = 1;
304 if (okay) {
305 struct strbuf target = STRBUF_INIT;
306 strbuf_add(&target, base, serverlen);
307 strbuf_add(&target, data + i, posn - i);
308 if (!strbuf_strip_suffix(&target, "objects")) {
309 warning("ignoring alternate that does"
310 " not end in 'objects': %s",
311 target.buf);
312 strbuf_release(&target);
313 } else if (is_alternate_allowed(target.buf)) {
314 warning("adding alternate object store: %s",
315 target.buf);
316 newalt = xmalloc(sizeof(*newalt));
317 newalt->next = NULL;
318 newalt->base = strbuf_detach(&target, NULL);
319 newalt->got_indices = 0;
320 newalt->packs = NULL;
322 while (tail->next != NULL)
323 tail = tail->next;
324 tail->next = newalt;
325 } else {
326 strbuf_release(&target);
330 i = posn + 1;
333 cdata->got_alternates = 1;
336 static void fetch_alternates(struct walker *walker, const char *base)
338 struct strbuf buffer = STRBUF_INIT;
339 struct strbuf url = STRBUF_INIT;
340 struct active_request_slot *slot;
341 struct alternates_request alt_req;
342 struct walker_data *cdata = walker->data;
345 * If another request has already started fetching alternates,
346 * wait for them to arrive and return to processing this request's
347 * curl message
349 #ifdef USE_CURL_MULTI
350 while (cdata->got_alternates == 0) {
351 step_active_slots();
353 #endif
355 /* Nothing to do if they've already been fetched */
356 if (cdata->got_alternates == 1)
357 return;
359 /* Start the fetch */
360 cdata->got_alternates = 0;
362 if (walker->get_verbosely)
363 fprintf(stderr, "Getting alternates list for %s\n", base);
365 strbuf_addf(&url, "%s/objects/info/http-alternates", base);
368 * Use a callback to process the result, since another request
369 * may fail and need to have alternates loaded before continuing
371 slot = get_active_slot();
372 slot->callback_func = process_alternates_response;
373 alt_req.walker = walker;
374 slot->callback_data = &alt_req;
376 curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
377 curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
378 curl_easy_setopt(slot->curl, CURLOPT_URL, url.buf);
380 alt_req.base = base;
381 alt_req.url = &url;
382 alt_req.buffer = &buffer;
383 alt_req.http_specific = 1;
384 alt_req.slot = slot;
386 if (start_active_slot(slot))
387 run_active_slot(slot);
388 else
389 cdata->got_alternates = -1;
391 strbuf_release(&buffer);
392 strbuf_release(&url);
395 static int fetch_indices(struct walker *walker, struct alt_base *repo)
397 int ret;
399 if (repo->got_indices)
400 return 0;
402 if (walker->get_verbosely)
403 fprintf(stderr, "Getting pack list for %s\n", repo->base);
405 switch (http_get_info_packs(repo->base, &repo->packs)) {
406 case HTTP_OK:
407 case HTTP_MISSING_TARGET:
408 repo->got_indices = 1;
409 ret = 0;
410 break;
411 default:
412 repo->got_indices = 0;
413 ret = -1;
416 return ret;
419 static int http_fetch_pack(struct walker *walker, struct alt_base *repo, unsigned char *sha1)
421 struct packed_git *target;
422 int ret;
423 struct slot_results results;
424 struct http_pack_request *preq;
426 if (fetch_indices(walker, repo))
427 return -1;
428 target = find_sha1_pack(sha1, repo->packs);
429 if (!target)
430 return -1;
432 if (walker->get_verbosely) {
433 fprintf(stderr, "Getting pack %s\n",
434 sha1_to_hex(target->sha1));
435 fprintf(stderr, " which contains %s\n",
436 sha1_to_hex(sha1));
439 preq = new_http_pack_request(target, repo->base);
440 if (preq == NULL)
441 goto abort;
442 preq->lst = &repo->packs;
443 preq->slot->results = &results;
445 if (start_active_slot(preq->slot)) {
446 run_active_slot(preq->slot);
447 if (results.curl_result != CURLE_OK) {
448 error("Unable to get pack file %s\n%s", preq->url,
449 curl_errorstr);
450 goto abort;
452 } else {
453 error("Unable to start request");
454 goto abort;
457 ret = finish_http_pack_request(preq);
458 release_http_pack_request(preq);
459 if (ret)
460 return ret;
462 return 0;
464 abort:
465 return -1;
468 static void abort_object_request(struct object_request *obj_req)
470 release_object_request(obj_req);
473 static int fetch_object(struct walker *walker, unsigned char *sha1)
475 char *hex = sha1_to_hex(sha1);
476 int ret = 0;
477 struct object_request *obj_req = NULL;
478 struct http_object_request *req;
479 struct list_head *pos, *head = &object_queue_head;
481 list_for_each(pos, head) {
482 obj_req = list_entry(pos, struct object_request, node);
483 if (!hashcmp(obj_req->sha1, sha1))
484 break;
486 if (obj_req == NULL)
487 return error("Couldn't find request for %s in the queue", hex);
489 if (has_sha1_file(obj_req->sha1)) {
490 if (obj_req->req != NULL)
491 abort_http_object_request(obj_req->req);
492 abort_object_request(obj_req);
493 return 0;
496 #ifdef USE_CURL_MULTI
497 while (obj_req->state == WAITING)
498 step_active_slots();
499 #else
500 start_object_request(walker, obj_req);
501 #endif
504 * obj_req->req might change when fetching alternates in the callback
505 * process_object_response; therefore, the "shortcut" variable, req,
506 * is used only after we're done with slots.
508 while (obj_req->state == ACTIVE)
509 run_active_slot(obj_req->req->slot);
511 req = obj_req->req;
513 if (req->localfile != -1) {
514 close(req->localfile);
515 req->localfile = -1;
519 * we turned off CURLOPT_FAILONERROR to avoid losing a
520 * persistent connection and got CURLE_OK.
522 if (req->http_code >= 300 && req->curl_result == CURLE_OK &&
523 (starts_with(req->url, "http://") ||
524 starts_with(req->url, "https://"))) {
525 req->curl_result = CURLE_HTTP_RETURNED_ERROR;
526 xsnprintf(req->errorstr, sizeof(req->errorstr),
527 "HTTP request failed");
530 if (obj_req->state == ABORTED) {
531 ret = error("Request for %s aborted", hex);
532 } else if (req->curl_result != CURLE_OK &&
533 req->http_code != 416) {
534 if (missing_target(req))
535 ret = -1; /* Be silent, it is probably in a pack. */
536 else
537 ret = error("%s (curl_result = %d, http_code = %ld, sha1 = %s)",
538 req->errorstr, req->curl_result,
539 req->http_code, hex);
540 } else if (req->zret != Z_STREAM_END) {
541 walker->corrupt_object_found++;
542 ret = error("File %s (%s) corrupt", hex, req->url);
543 } else if (hashcmp(obj_req->sha1, req->real_sha1)) {
544 ret = error("File %s has bad hash", hex);
545 } else if (req->rename < 0) {
546 ret = error("unable to write sha1 filename %s",
547 sha1_file_name(req->sha1));
550 release_http_object_request(req);
551 release_object_request(obj_req);
552 return ret;
555 static int fetch(struct walker *walker, unsigned char *sha1)
557 struct walker_data *data = walker->data;
558 struct alt_base *altbase = data->alt;
560 if (!fetch_object(walker, sha1))
561 return 0;
562 while (altbase) {
563 if (!http_fetch_pack(walker, altbase, sha1))
564 return 0;
565 fetch_alternates(walker, data->alt->base);
566 altbase = altbase->next;
568 return error("Unable to find %s under %s", sha1_to_hex(sha1),
569 data->alt->base);
572 static int fetch_ref(struct walker *walker, struct ref *ref)
574 struct walker_data *data = walker->data;
575 return http_fetch_ref(data->alt->base, ref);
578 static void cleanup(struct walker *walker)
580 struct walker_data *data = walker->data;
581 struct alt_base *alt, *alt_next;
583 if (data) {
584 alt = data->alt;
585 while (alt) {
586 alt_next = alt->next;
588 free(alt->base);
589 free(alt);
591 alt = alt_next;
593 free(data);
594 walker->data = NULL;
598 struct walker *get_http_walker(const char *url)
600 char *s;
601 struct walker_data *data = xmalloc(sizeof(struct walker_data));
602 struct walker *walker = xmalloc(sizeof(struct walker));
604 data->alt = xmalloc(sizeof(*data->alt));
605 data->alt->base = xstrdup(url);
606 for (s = data->alt->base + strlen(data->alt->base) - 1; *s == '/'; --s)
607 *s = 0;
609 data->alt->got_indices = 0;
610 data->alt->packs = NULL;
611 data->alt->next = NULL;
612 data->got_alternates = -1;
614 walker->corrupt_object_found = 0;
615 walker->fetch = fetch;
616 walker->fetch_ref = fetch_ref;
617 walker->prefetch = prefetch;
618 walker->cleanup = cleanup;
619 walker->data = data;
621 #ifdef USE_CURL_MULTI
622 add_fill_function(walker, (int (*)(void *)) fill_active_slot);
623 #endif
625 return walker;