Start preparing for 1.8.4.2
[alt-git.git] / http-walker.c
blob1516c5eb290746bad4551515fda7930d2f55d32b
1 #include "cache.h"
2 #include "commit.h"
3 #include "walker.h"
4 #include "http.h"
6 struct alt_base {
7 char *base;
8 int got_indices;
9 struct packed_git *packs;
10 struct alt_base *next;
13 enum object_request_state {
14 WAITING,
15 ABORTED,
16 ACTIVE,
17 COMPLETE
20 struct object_request {
21 struct walker *walker;
22 unsigned char sha1[20];
23 struct alt_base *repo;
24 enum object_request_state state;
25 struct http_object_request *req;
26 struct object_request *next;
29 struct alternates_request {
30 struct walker *walker;
31 const char *base;
32 char *url;
33 struct strbuf *buffer;
34 struct active_request_slot *slot;
35 int http_specific;
38 struct walker_data {
39 const char *url;
40 int got_alternates;
41 struct alt_base *alt;
44 static struct object_request *object_queue_head;
46 static void fetch_alternates(struct walker *walker, const char *base);
48 static void process_object_response(void *callback_data);
50 static void start_object_request(struct walker *walker,
51 struct object_request *obj_req)
53 struct active_request_slot *slot;
54 struct http_object_request *req;
56 req = new_http_object_request(obj_req->repo->base, obj_req->sha1);
57 if (req == NULL) {
58 obj_req->state = ABORTED;
59 return;
61 obj_req->req = req;
63 slot = req->slot;
64 slot->callback_func = process_object_response;
65 slot->callback_data = obj_req;
67 /* Try to get the request started, abort the request on error */
68 obj_req->state = ACTIVE;
69 if (!start_active_slot(slot)) {
70 obj_req->state = ABORTED;
71 release_http_object_request(req);
72 return;
76 static void finish_object_request(struct object_request *obj_req)
78 if (finish_http_object_request(obj_req->req))
79 return;
81 if (obj_req->req->rename == 0)
82 walker_say(obj_req->walker, "got %s\n", sha1_to_hex(obj_req->sha1));
85 static void process_object_response(void *callback_data)
87 struct object_request *obj_req =
88 (struct object_request *)callback_data;
89 struct walker *walker = obj_req->walker;
90 struct walker_data *data = walker->data;
91 struct alt_base *alt = data->alt;
93 process_http_object_request(obj_req->req);
94 obj_req->state = COMPLETE;
96 /* Use alternates if necessary */
97 if (missing_target(obj_req->req)) {
98 fetch_alternates(walker, alt->base);
99 if (obj_req->repo->next != NULL) {
100 obj_req->repo =
101 obj_req->repo->next;
102 release_http_object_request(obj_req->req);
103 start_object_request(walker, obj_req);
104 return;
108 finish_object_request(obj_req);
111 static void release_object_request(struct object_request *obj_req)
113 struct object_request *entry = object_queue_head;
115 if (obj_req->req !=NULL && obj_req->req->localfile != -1)
116 error("fd leakage in release: %d", obj_req->req->localfile);
117 if (obj_req == object_queue_head) {
118 object_queue_head = obj_req->next;
119 } else {
120 while (entry->next != NULL && entry->next != obj_req)
121 entry = entry->next;
122 if (entry->next == obj_req)
123 entry->next = entry->next->next;
126 free(obj_req);
129 #ifdef USE_CURL_MULTI
130 static int fill_active_slot(struct walker *walker)
132 struct object_request *obj_req;
134 for (obj_req = object_queue_head; obj_req; obj_req = obj_req->next) {
135 if (obj_req->state == WAITING) {
136 if (has_sha1_file(obj_req->sha1))
137 obj_req->state = COMPLETE;
138 else {
139 start_object_request(walker, obj_req);
140 return 1;
144 return 0;
146 #endif
148 static void prefetch(struct walker *walker, unsigned char *sha1)
150 struct object_request *newreq;
151 struct object_request *tail;
152 struct walker_data *data = walker->data;
154 newreq = xmalloc(sizeof(*newreq));
155 newreq->walker = walker;
156 hashcpy(newreq->sha1, sha1);
157 newreq->repo = data->alt;
158 newreq->state = WAITING;
159 newreq->req = NULL;
160 newreq->next = NULL;
162 http_is_verbose = walker->get_verbosely;
164 if (object_queue_head == NULL) {
165 object_queue_head = newreq;
166 } else {
167 tail = object_queue_head;
168 while (tail->next != NULL)
169 tail = tail->next;
170 tail->next = newreq;
173 #ifdef USE_CURL_MULTI
174 fill_active_slots();
175 step_active_slots();
176 #endif
179 static void process_alternates_response(void *callback_data)
181 struct alternates_request *alt_req =
182 (struct alternates_request *)callback_data;
183 struct walker *walker = alt_req->walker;
184 struct walker_data *cdata = walker->data;
185 struct active_request_slot *slot = alt_req->slot;
186 struct alt_base *tail = cdata->alt;
187 const char *base = alt_req->base;
188 const char null_byte = '\0';
189 char *data;
190 int i = 0;
192 if (alt_req->http_specific) {
193 if (slot->curl_result != CURLE_OK ||
194 !alt_req->buffer->len) {
196 /* Try reusing the slot to get non-http alternates */
197 alt_req->http_specific = 0;
198 sprintf(alt_req->url, "%s/objects/info/alternates",
199 base);
200 curl_easy_setopt(slot->curl, CURLOPT_URL,
201 alt_req->url);
202 active_requests++;
203 slot->in_use = 1;
204 if (slot->finished != NULL)
205 (*slot->finished) = 0;
206 if (!start_active_slot(slot)) {
207 cdata->got_alternates = -1;
208 slot->in_use = 0;
209 if (slot->finished != NULL)
210 (*slot->finished) = 1;
212 return;
214 } else if (slot->curl_result != CURLE_OK) {
215 if (!missing_target(slot)) {
216 cdata->got_alternates = -1;
217 return;
221 fwrite_buffer((char *)&null_byte, 1, 1, alt_req->buffer);
222 alt_req->buffer->len--;
223 data = alt_req->buffer->buf;
225 while (i < alt_req->buffer->len) {
226 int posn = i;
227 while (posn < alt_req->buffer->len && data[posn] != '\n')
228 posn++;
229 if (data[posn] == '\n') {
230 int okay = 0;
231 int serverlen = 0;
232 struct alt_base *newalt;
233 char *target = NULL;
234 if (data[i] == '/') {
236 * This counts
237 * http://git.host/pub/scm/linux.git/
238 * -----------here^
239 * so memcpy(dst, base, serverlen) will
240 * copy up to "...git.host".
242 const char *colon_ss = strstr(base,"://");
243 if (colon_ss) {
244 serverlen = (strchr(colon_ss + 3, '/')
245 - base);
246 okay = 1;
248 } else if (!memcmp(data + i, "../", 3)) {
250 * Relative URL; chop the corresponding
251 * number of subpath from base (and ../
252 * from data), and concatenate the result.
254 * The code first drops ../ from data, and
255 * then drops one ../ from data and one path
256 * from base. IOW, one extra ../ is dropped
257 * from data than path is dropped from base.
259 * This is not wrong. The alternate in
260 * http://git.host/pub/scm/linux.git/
261 * to borrow from
262 * http://git.host/pub/scm/linus.git/
263 * is ../../linus.git/objects/. You need
264 * two ../../ to borrow from your direct
265 * neighbour.
267 i += 3;
268 serverlen = strlen(base);
269 while (i + 2 < posn &&
270 !memcmp(data + i, "../", 3)) {
271 do {
272 serverlen--;
273 } while (serverlen &&
274 base[serverlen - 1] != '/');
275 i += 3;
277 /* If the server got removed, give up. */
278 okay = strchr(base, ':') - base + 3 <
279 serverlen;
280 } else if (alt_req->http_specific) {
281 char *colon = strchr(data + i, ':');
282 char *slash = strchr(data + i, '/');
283 if (colon && slash && colon < data + posn &&
284 slash < data + posn && colon < slash) {
285 okay = 1;
288 /* skip "objects\n" at end */
289 if (okay) {
290 target = xmalloc(serverlen + posn - i - 6);
291 memcpy(target, base, serverlen);
292 memcpy(target + serverlen, data + i,
293 posn - i - 7);
294 target[serverlen + posn - i - 7] = 0;
295 if (walker->get_verbosely)
296 fprintf(stderr,
297 "Also look at %s\n", target);
298 newalt = xmalloc(sizeof(*newalt));
299 newalt->next = NULL;
300 newalt->base = target;
301 newalt->got_indices = 0;
302 newalt->packs = NULL;
304 while (tail->next != NULL)
305 tail = tail->next;
306 tail->next = newalt;
309 i = posn + 1;
312 cdata->got_alternates = 1;
315 static void fetch_alternates(struct walker *walker, const char *base)
317 struct strbuf buffer = STRBUF_INIT;
318 char *url;
319 struct active_request_slot *slot;
320 struct alternates_request alt_req;
321 struct walker_data *cdata = walker->data;
324 * If another request has already started fetching alternates,
325 * wait for them to arrive and return to processing this request's
326 * curl message
328 #ifdef USE_CURL_MULTI
329 while (cdata->got_alternates == 0) {
330 step_active_slots();
332 #endif
334 /* Nothing to do if they've already been fetched */
335 if (cdata->got_alternates == 1)
336 return;
338 /* Start the fetch */
339 cdata->got_alternates = 0;
341 if (walker->get_verbosely)
342 fprintf(stderr, "Getting alternates list for %s\n", base);
344 url = xmalloc(strlen(base) + 31);
345 sprintf(url, "%s/objects/info/http-alternates", base);
348 * Use a callback to process the result, since another request
349 * may fail and need to have alternates loaded before continuing
351 slot = get_active_slot();
352 slot->callback_func = process_alternates_response;
353 alt_req.walker = walker;
354 slot->callback_data = &alt_req;
356 curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
357 curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
358 curl_easy_setopt(slot->curl, CURLOPT_URL, url);
360 alt_req.base = base;
361 alt_req.url = url;
362 alt_req.buffer = &buffer;
363 alt_req.http_specific = 1;
364 alt_req.slot = slot;
366 if (start_active_slot(slot))
367 run_active_slot(slot);
368 else
369 cdata->got_alternates = -1;
371 strbuf_release(&buffer);
372 free(url);
375 static int fetch_indices(struct walker *walker, struct alt_base *repo)
377 int ret;
379 if (repo->got_indices)
380 return 0;
382 if (walker->get_verbosely)
383 fprintf(stderr, "Getting pack list for %s\n", repo->base);
385 switch (http_get_info_packs(repo->base, &repo->packs)) {
386 case HTTP_OK:
387 case HTTP_MISSING_TARGET:
388 repo->got_indices = 1;
389 ret = 0;
390 break;
391 default:
392 repo->got_indices = 0;
393 ret = -1;
396 return ret;
399 static int http_fetch_pack(struct walker *walker, struct alt_base *repo, unsigned char *sha1)
401 struct packed_git *target;
402 int ret;
403 struct slot_results results;
404 struct http_pack_request *preq;
406 if (fetch_indices(walker, repo))
407 return -1;
408 target = find_sha1_pack(sha1, repo->packs);
409 if (!target)
410 return -1;
412 if (walker->get_verbosely) {
413 fprintf(stderr, "Getting pack %s\n",
414 sha1_to_hex(target->sha1));
415 fprintf(stderr, " which contains %s\n",
416 sha1_to_hex(sha1));
419 preq = new_http_pack_request(target, repo->base);
420 if (preq == NULL)
421 goto abort;
422 preq->lst = &repo->packs;
423 preq->slot->results = &results;
425 if (start_active_slot(preq->slot)) {
426 run_active_slot(preq->slot);
427 if (results.curl_result != CURLE_OK) {
428 error("Unable to get pack file %s\n%s", preq->url,
429 curl_errorstr);
430 goto abort;
432 } else {
433 error("Unable to start request");
434 goto abort;
437 ret = finish_http_pack_request(preq);
438 release_http_pack_request(preq);
439 if (ret)
440 return ret;
442 return 0;
444 abort:
445 return -1;
448 static void abort_object_request(struct object_request *obj_req)
450 release_object_request(obj_req);
453 static int fetch_object(struct walker *walker, struct alt_base *repo, unsigned char *sha1)
455 char *hex = sha1_to_hex(sha1);
456 int ret = 0;
457 struct object_request *obj_req = object_queue_head;
458 struct http_object_request *req;
460 while (obj_req != NULL && hashcmp(obj_req->sha1, sha1))
461 obj_req = obj_req->next;
462 if (obj_req == NULL)
463 return error("Couldn't find request for %s in the queue", hex);
465 if (has_sha1_file(obj_req->sha1)) {
466 if (obj_req->req != NULL)
467 abort_http_object_request(obj_req->req);
468 abort_object_request(obj_req);
469 return 0;
472 #ifdef USE_CURL_MULTI
473 while (obj_req->state == WAITING)
474 step_active_slots();
475 #else
476 start_object_request(walker, obj_req);
477 #endif
480 * obj_req->req might change when fetching alternates in the callback
481 * process_object_response; therefore, the "shortcut" variable, req,
482 * is used only after we're done with slots.
484 while (obj_req->state == ACTIVE)
485 run_active_slot(obj_req->req->slot);
487 req = obj_req->req;
489 if (req->localfile != -1) {
490 close(req->localfile);
491 req->localfile = -1;
494 if (obj_req->state == ABORTED) {
495 ret = error("Request for %s aborted", hex);
496 } else if (req->curl_result != CURLE_OK &&
497 req->http_code != 416) {
498 if (missing_target(req))
499 ret = -1; /* Be silent, it is probably in a pack. */
500 else
501 ret = error("%s (curl_result = %d, http_code = %ld, sha1 = %s)",
502 req->errorstr, req->curl_result,
503 req->http_code, hex);
504 } else if (req->zret != Z_STREAM_END) {
505 walker->corrupt_object_found++;
506 ret = error("File %s (%s) corrupt", hex, req->url);
507 } else if (hashcmp(obj_req->sha1, req->real_sha1)) {
508 ret = error("File %s has bad hash", hex);
509 } else if (req->rename < 0) {
510 ret = error("unable to write sha1 filename %s",
511 sha1_file_name(req->sha1));
514 release_http_object_request(req);
515 release_object_request(obj_req);
516 return ret;
519 static int fetch(struct walker *walker, unsigned char *sha1)
521 struct walker_data *data = walker->data;
522 struct alt_base *altbase = data->alt;
524 if (!fetch_object(walker, altbase, sha1))
525 return 0;
526 while (altbase) {
527 if (!http_fetch_pack(walker, altbase, sha1))
528 return 0;
529 fetch_alternates(walker, data->alt->base);
530 altbase = altbase->next;
532 return error("Unable to find %s under %s", sha1_to_hex(sha1),
533 data->alt->base);
536 static int fetch_ref(struct walker *walker, struct ref *ref)
538 struct walker_data *data = walker->data;
539 return http_fetch_ref(data->alt->base, ref);
542 static void cleanup(struct walker *walker)
544 struct walker_data *data = walker->data;
545 struct alt_base *alt, *alt_next;
547 if (data) {
548 alt = data->alt;
549 while (alt) {
550 alt_next = alt->next;
552 free(alt->base);
553 free(alt);
555 alt = alt_next;
557 free(data);
558 walker->data = NULL;
562 struct walker *get_http_walker(const char *url)
564 char *s;
565 struct walker_data *data = xmalloc(sizeof(struct walker_data));
566 struct walker *walker = xmalloc(sizeof(struct walker));
568 data->alt = xmalloc(sizeof(*data->alt));
569 data->alt->base = xmalloc(strlen(url) + 1);
570 strcpy(data->alt->base, url);
571 for (s = data->alt->base + strlen(data->alt->base) - 1; *s == '/'; --s)
572 *s = 0;
574 data->alt->got_indices = 0;
575 data->alt->packs = NULL;
576 data->alt->next = NULL;
577 data->got_alternates = -1;
579 walker->corrupt_object_found = 0;
580 walker->fetch = fetch;
581 walker->fetch_ref = fetch_ref;
582 walker->prefetch = prefetch;
583 walker->cleanup = cleanup;
584 walker->data = data;
586 #ifdef USE_CURL_MULTI
587 add_fill_function(walker, (int (*)(void *)) fill_active_slot);
588 #endif
590 return walker;