]> git.ipfire.org Git - thirdparty/git.git/blob - http-walker.c
Merge branch 'ab/gc-reflog'
[thirdparty/git.git] / http-walker.c
1 #include "cache.h"
2 #include "repository.h"
3 #include "commit.h"
4 #include "walker.h"
5 #include "http.h"
6 #include "list.h"
7 #include "transport.h"
8 #include "packfile.h"
9 #include "object-store.h"
10
11 struct alt_base {
12 char *base;
13 int got_indices;
14 struct packed_git *packs;
15 struct alt_base *next;
16 };
17
18 enum object_request_state {
19 WAITING,
20 ABORTED,
21 ACTIVE,
22 COMPLETE
23 };
24
25 struct object_request {
26 struct walker *walker;
27 struct object_id oid;
28 struct alt_base *repo;
29 enum object_request_state state;
30 struct http_object_request *req;
31 struct list_head node;
32 };
33
34 struct alternates_request {
35 struct walker *walker;
36 const char *base;
37 struct strbuf *url;
38 struct strbuf *buffer;
39 struct active_request_slot *slot;
40 int http_specific;
41 };
42
43 struct walker_data {
44 const char *url;
45 int got_alternates;
46 struct alt_base *alt;
47 };
48
49 static LIST_HEAD(object_queue_head);
50
51 static void fetch_alternates(struct walker *walker, const char *base);
52
53 static void process_object_response(void *callback_data);
54
55 static void start_object_request(struct walker *walker,
56 struct object_request *obj_req)
57 {
58 struct active_request_slot *slot;
59 struct http_object_request *req;
60
61 req = new_http_object_request(obj_req->repo->base, &obj_req->oid);
62 if (req == NULL) {
63 obj_req->state = ABORTED;
64 return;
65 }
66 obj_req->req = req;
67
68 slot = req->slot;
69 slot->callback_func = process_object_response;
70 slot->callback_data = obj_req;
71
72 /* Try to get the request started, abort the request on error */
73 obj_req->state = ACTIVE;
74 if (!start_active_slot(slot)) {
75 obj_req->state = ABORTED;
76 release_http_object_request(req);
77 return;
78 }
79 }
80
81 static void finish_object_request(struct object_request *obj_req)
82 {
83 if (finish_http_object_request(obj_req->req))
84 return;
85
86 if (obj_req->req->rename == 0)
87 walker_say(obj_req->walker, "got %s\n", oid_to_hex(&obj_req->oid));
88 }
89
90 static void process_object_response(void *callback_data)
91 {
92 struct object_request *obj_req =
93 (struct object_request *)callback_data;
94 struct walker *walker = obj_req->walker;
95 struct walker_data *data = walker->data;
96 struct alt_base *alt = data->alt;
97
98 process_http_object_request(obj_req->req);
99 obj_req->state = COMPLETE;
100
101 normalize_curl_result(&obj_req->req->curl_result,
102 obj_req->req->http_code,
103 obj_req->req->errorstr,
104 sizeof(obj_req->req->errorstr));
105
106 /* Use alternates if necessary */
107 if (missing_target(obj_req->req)) {
108 fetch_alternates(walker, alt->base);
109 if (obj_req->repo->next != NULL) {
110 obj_req->repo =
111 obj_req->repo->next;
112 release_http_object_request(obj_req->req);
113 start_object_request(walker, obj_req);
114 return;
115 }
116 }
117
118 finish_object_request(obj_req);
119 }
120
121 static void release_object_request(struct object_request *obj_req)
122 {
123 if (obj_req->req !=NULL && obj_req->req->localfile != -1)
124 error("fd leakage in release: %d", obj_req->req->localfile);
125
126 list_del(&obj_req->node);
127 free(obj_req);
128 }
129
130 #ifdef USE_CURL_MULTI
131 static int fill_active_slot(struct walker *walker)
132 {
133 struct object_request *obj_req;
134 struct list_head *pos, *tmp, *head = &object_queue_head;
135
136 list_for_each_safe(pos, tmp, head) {
137 obj_req = list_entry(pos, struct object_request, node);
138 if (obj_req->state == WAITING) {
139 if (has_object_file(&obj_req->oid))
140 obj_req->state = COMPLETE;
141 else {
142 start_object_request(walker, obj_req);
143 return 1;
144 }
145 }
146 }
147 return 0;
148 }
149 #endif
150
151 static void prefetch(struct walker *walker, unsigned char *sha1)
152 {
153 struct object_request *newreq;
154 struct walker_data *data = walker->data;
155
156 newreq = xmalloc(sizeof(*newreq));
157 newreq->walker = walker;
158 hashcpy(newreq->oid.hash, sha1);
159 newreq->repo = data->alt;
160 newreq->state = WAITING;
161 newreq->req = NULL;
162
163 http_is_verbose = walker->get_verbosely;
164 list_add_tail(&newreq->node, &object_queue_head);
165
166 #ifdef USE_CURL_MULTI
167 fill_active_slots();
168 step_active_slots();
169 #endif
170 }
171
172 static int is_alternate_allowed(const char *url)
173 {
174 const char *protocols[] = {
175 "http", "https", "ftp", "ftps"
176 };
177 int i;
178
179 if (http_follow_config != HTTP_FOLLOW_ALWAYS) {
180 warning("alternate disabled by http.followRedirects: %s", url);
181 return 0;
182 }
183
184 for (i = 0; i < ARRAY_SIZE(protocols); i++) {
185 const char *end;
186 if (skip_prefix(url, protocols[i], &end) &&
187 starts_with(end, "://"))
188 break;
189 }
190
191 if (i >= ARRAY_SIZE(protocols)) {
192 warning("ignoring alternate with unknown protocol: %s", url);
193 return 0;
194 }
195 if (!is_transport_allowed(protocols[i], 0)) {
196 warning("ignoring alternate with restricted protocol: %s", url);
197 return 0;
198 }
199
200 return 1;
201 }
202
203 static void process_alternates_response(void *callback_data)
204 {
205 struct alternates_request *alt_req =
206 (struct alternates_request *)callback_data;
207 struct walker *walker = alt_req->walker;
208 struct walker_data *cdata = walker->data;
209 struct active_request_slot *slot = alt_req->slot;
210 struct alt_base *tail = cdata->alt;
211 const char *base = alt_req->base;
212 const char null_byte = '\0';
213 char *data;
214 int i = 0;
215
216 normalize_curl_result(&slot->curl_result, slot->http_code,
217 curl_errorstr, sizeof(curl_errorstr));
218
219 if (alt_req->http_specific) {
220 if (slot->curl_result != CURLE_OK ||
221 !alt_req->buffer->len) {
222
223 /* Try reusing the slot to get non-http alternates */
224 alt_req->http_specific = 0;
225 strbuf_reset(alt_req->url);
226 strbuf_addf(alt_req->url, "%s/objects/info/alternates",
227 base);
228 curl_easy_setopt(slot->curl, CURLOPT_URL,
229 alt_req->url->buf);
230 active_requests++;
231 slot->in_use = 1;
232 if (slot->finished != NULL)
233 (*slot->finished) = 0;
234 if (!start_active_slot(slot)) {
235 cdata->got_alternates = -1;
236 slot->in_use = 0;
237 if (slot->finished != NULL)
238 (*slot->finished) = 1;
239 }
240 return;
241 }
242 } else if (slot->curl_result != CURLE_OK) {
243 if (!missing_target(slot)) {
244 cdata->got_alternates = -1;
245 return;
246 }
247 }
248
249 fwrite_buffer((char *)&null_byte, 1, 1, alt_req->buffer);
250 alt_req->buffer->len--;
251 data = alt_req->buffer->buf;
252
253 while (i < alt_req->buffer->len) {
254 int posn = i;
255 while (posn < alt_req->buffer->len && data[posn] != '\n')
256 posn++;
257 if (data[posn] == '\n') {
258 int okay = 0;
259 int serverlen = 0;
260 struct alt_base *newalt;
261 if (data[i] == '/') {
262 /*
263 * This counts
264 * http://git.host/pub/scm/linux.git/
265 * -----------here^
266 * so memcpy(dst, base, serverlen) will
267 * copy up to "...git.host".
268 */
269 const char *colon_ss = strstr(base,"://");
270 if (colon_ss) {
271 serverlen = (strchr(colon_ss + 3, '/')
272 - base);
273 okay = 1;
274 }
275 } else if (!memcmp(data + i, "../", 3)) {
276 /*
277 * Relative URL; chop the corresponding
278 * number of subpath from base (and ../
279 * from data), and concatenate the result.
280 *
281 * The code first drops ../ from data, and
282 * then drops one ../ from data and one path
283 * from base. IOW, one extra ../ is dropped
284 * from data than path is dropped from base.
285 *
286 * This is not wrong. The alternate in
287 * http://git.host/pub/scm/linux.git/
288 * to borrow from
289 * http://git.host/pub/scm/linus.git/
290 * is ../../linus.git/objects/. You need
291 * two ../../ to borrow from your direct
292 * neighbour.
293 */
294 i += 3;
295 serverlen = strlen(base);
296 while (i + 2 < posn &&
297 !memcmp(data + i, "../", 3)) {
298 do {
299 serverlen--;
300 } while (serverlen &&
301 base[serverlen - 1] != '/');
302 i += 3;
303 }
304 /* If the server got removed, give up. */
305 okay = strchr(base, ':') - base + 3 <
306 serverlen;
307 } else if (alt_req->http_specific) {
308 char *colon = strchr(data + i, ':');
309 char *slash = strchr(data + i, '/');
310 if (colon && slash && colon < data + posn &&
311 slash < data + posn && colon < slash) {
312 okay = 1;
313 }
314 }
315 if (okay) {
316 struct strbuf target = STRBUF_INIT;
317 strbuf_add(&target, base, serverlen);
318 strbuf_add(&target, data + i, posn - i);
319 if (!strbuf_strip_suffix(&target, "objects")) {
320 warning("ignoring alternate that does"
321 " not end in 'objects': %s",
322 target.buf);
323 strbuf_release(&target);
324 } else if (is_alternate_allowed(target.buf)) {
325 warning("adding alternate object store: %s",
326 target.buf);
327 newalt = xmalloc(sizeof(*newalt));
328 newalt->next = NULL;
329 newalt->base = strbuf_detach(&target, NULL);
330 newalt->got_indices = 0;
331 newalt->packs = NULL;
332
333 while (tail->next != NULL)
334 tail = tail->next;
335 tail->next = newalt;
336 } else {
337 strbuf_release(&target);
338 }
339 }
340 }
341 i = posn + 1;
342 }
343
344 cdata->got_alternates = 1;
345 }
346
347 static void fetch_alternates(struct walker *walker, const char *base)
348 {
349 struct strbuf buffer = STRBUF_INIT;
350 struct strbuf url = STRBUF_INIT;
351 struct active_request_slot *slot;
352 struct alternates_request alt_req;
353 struct walker_data *cdata = walker->data;
354
355 /*
356 * If another request has already started fetching alternates,
357 * wait for them to arrive and return to processing this request's
358 * curl message
359 */
360 #ifdef USE_CURL_MULTI
361 while (cdata->got_alternates == 0) {
362 step_active_slots();
363 }
364 #endif
365
366 /* Nothing to do if they've already been fetched */
367 if (cdata->got_alternates == 1)
368 return;
369
370 /* Start the fetch */
371 cdata->got_alternates = 0;
372
373 if (walker->get_verbosely)
374 fprintf(stderr, "Getting alternates list for %s\n", base);
375
376 strbuf_addf(&url, "%s/objects/info/http-alternates", base);
377
378 /*
379 * Use a callback to process the result, since another request
380 * may fail and need to have alternates loaded before continuing
381 */
382 slot = get_active_slot();
383 slot->callback_func = process_alternates_response;
384 alt_req.walker = walker;
385 slot->callback_data = &alt_req;
386
387 curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
388 curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
389 curl_easy_setopt(slot->curl, CURLOPT_URL, url.buf);
390
391 alt_req.base = base;
392 alt_req.url = &url;
393 alt_req.buffer = &buffer;
394 alt_req.http_specific = 1;
395 alt_req.slot = slot;
396
397 if (start_active_slot(slot))
398 run_active_slot(slot);
399 else
400 cdata->got_alternates = -1;
401
402 strbuf_release(&buffer);
403 strbuf_release(&url);
404 }
405
406 static int fetch_indices(struct walker *walker, struct alt_base *repo)
407 {
408 int ret;
409
410 if (repo->got_indices)
411 return 0;
412
413 if (walker->get_verbosely)
414 fprintf(stderr, "Getting pack list for %s\n", repo->base);
415
416 switch (http_get_info_packs(repo->base, &repo->packs)) {
417 case HTTP_OK:
418 case HTTP_MISSING_TARGET:
419 repo->got_indices = 1;
420 ret = 0;
421 break;
422 default:
423 repo->got_indices = 0;
424 ret = -1;
425 }
426
427 return ret;
428 }
429
430 static int http_fetch_pack(struct walker *walker, struct alt_base *repo, unsigned char *sha1)
431 {
432 struct packed_git *target;
433 int ret;
434 struct slot_results results;
435 struct http_pack_request *preq;
436
437 if (fetch_indices(walker, repo))
438 return -1;
439 target = find_sha1_pack(sha1, repo->packs);
440 if (!target)
441 return -1;
442
443 if (walker->get_verbosely) {
444 fprintf(stderr, "Getting pack %s\n",
445 sha1_to_hex(target->sha1));
446 fprintf(stderr, " which contains %s\n",
447 sha1_to_hex(sha1));
448 }
449
450 preq = new_http_pack_request(target, repo->base);
451 if (preq == NULL)
452 goto abort;
453 preq->lst = &repo->packs;
454 preq->slot->results = &results;
455
456 if (start_active_slot(preq->slot)) {
457 run_active_slot(preq->slot);
458 if (results.curl_result != CURLE_OK) {
459 error("Unable to get pack file %s\n%s", preq->url,
460 curl_errorstr);
461 goto abort;
462 }
463 } else {
464 error("Unable to start request");
465 goto abort;
466 }
467
468 ret = finish_http_pack_request(preq);
469 release_http_pack_request(preq);
470 if (ret)
471 return ret;
472
473 return 0;
474
475 abort:
476 return -1;
477 }
478
479 static void abort_object_request(struct object_request *obj_req)
480 {
481 release_object_request(obj_req);
482 }
483
484 static int fetch_object(struct walker *walker, unsigned char *sha1)
485 {
486 char *hex = sha1_to_hex(sha1);
487 int ret = 0;
488 struct object_request *obj_req = NULL;
489 struct http_object_request *req;
490 struct list_head *pos, *head = &object_queue_head;
491
492 list_for_each(pos, head) {
493 obj_req = list_entry(pos, struct object_request, node);
494 if (hasheq(obj_req->oid.hash, sha1))
495 break;
496 }
497 if (obj_req == NULL)
498 return error("Couldn't find request for %s in the queue", hex);
499
500 if (has_object_file(&obj_req->oid)) {
501 if (obj_req->req != NULL)
502 abort_http_object_request(obj_req->req);
503 abort_object_request(obj_req);
504 return 0;
505 }
506
507 #ifdef USE_CURL_MULTI
508 while (obj_req->state == WAITING)
509 step_active_slots();
510 #else
511 start_object_request(walker, obj_req);
512 #endif
513
514 /*
515 * obj_req->req might change when fetching alternates in the callback
516 * process_object_response; therefore, the "shortcut" variable, req,
517 * is used only after we're done with slots.
518 */
519 while (obj_req->state == ACTIVE)
520 run_active_slot(obj_req->req->slot);
521
522 req = obj_req->req;
523
524 if (req->localfile != -1) {
525 close(req->localfile);
526 req->localfile = -1;
527 }
528
529 normalize_curl_result(&req->curl_result, req->http_code,
530 req->errorstr, sizeof(req->errorstr));
531
532 if (obj_req->state == ABORTED) {
533 ret = error("Request for %s aborted", hex);
534 } else if (req->curl_result != CURLE_OK &&
535 req->http_code != 416) {
536 if (missing_target(req))
537 ret = -1; /* Be silent, it is probably in a pack. */
538 else
539 ret = error("%s (curl_result = %d, http_code = %ld, sha1 = %s)",
540 req->errorstr, req->curl_result,
541 req->http_code, hex);
542 } else if (req->zret != Z_STREAM_END) {
543 walker->corrupt_object_found++;
544 ret = error("File %s (%s) corrupt", hex, req->url);
545 } else if (!oideq(&obj_req->oid, &req->real_oid)) {
546 ret = error("File %s has bad hash", hex);
547 } else if (req->rename < 0) {
548 struct strbuf buf = STRBUF_INIT;
549 loose_object_path(the_repository, &buf, &req->oid);
550 ret = error("unable to write sha1 filename %s", buf.buf);
551 strbuf_release(&buf);
552 }
553
554 release_http_object_request(req);
555 release_object_request(obj_req);
556 return ret;
557 }
558
559 static int fetch(struct walker *walker, unsigned char *sha1)
560 {
561 struct walker_data *data = walker->data;
562 struct alt_base *altbase = data->alt;
563
564 if (!fetch_object(walker, sha1))
565 return 0;
566 while (altbase) {
567 if (!http_fetch_pack(walker, altbase, sha1))
568 return 0;
569 fetch_alternates(walker, data->alt->base);
570 altbase = altbase->next;
571 }
572 return error("Unable to find %s under %s", sha1_to_hex(sha1),
573 data->alt->base);
574 }
575
576 static int fetch_ref(struct walker *walker, struct ref *ref)
577 {
578 struct walker_data *data = walker->data;
579 return http_fetch_ref(data->alt->base, ref);
580 }
581
582 static void cleanup(struct walker *walker)
583 {
584 struct walker_data *data = walker->data;
585 struct alt_base *alt, *alt_next;
586
587 if (data) {
588 alt = data->alt;
589 while (alt) {
590 alt_next = alt->next;
591
592 free(alt->base);
593 free(alt);
594
595 alt = alt_next;
596 }
597 free(data);
598 walker->data = NULL;
599 }
600 }
601
602 struct walker *get_http_walker(const char *url)
603 {
604 char *s;
605 struct walker_data *data = xmalloc(sizeof(struct walker_data));
606 struct walker *walker = xmalloc(sizeof(struct walker));
607
608 data->alt = xmalloc(sizeof(*data->alt));
609 data->alt->base = xstrdup(url);
610 for (s = data->alt->base + strlen(data->alt->base) - 1; *s == '/'; --s)
611 *s = 0;
612
613 data->alt->got_indices = 0;
614 data->alt->packs = NULL;
615 data->alt->next = NULL;
616 data->got_alternates = -1;
617
618 walker->corrupt_object_found = 0;
619 walker->fetch = fetch;
620 walker->fetch_ref = fetch_ref;
621 walker->prefetch = prefetch;
622 walker->cleanup = cleanup;
623 walker->data = data;
624
625 #ifdef USE_CURL_MULTI
626 add_fill_function(walker, (int (*)(void *)) fill_active_slot);
627 #endif
628
629 return walker;
630 }