Merge branch 'mg/status-porcelain-no-i18n' into maint
[git] / http-walker.c
1 #include "cache.h"
2 #include "commit.h"
3 #include "walker.h"
4 #include "http.h"
5 #include "list.h"
6 #include "transport.h"
7
8 struct alt_base {
9         char *base;
10         int got_indices;
11         struct packed_git *packs;
12         struct alt_base *next;
13 };
14
15 enum object_request_state {
16         WAITING,
17         ABORTED,
18         ACTIVE,
19         COMPLETE
20 };
21
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;
29 };
30
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;
38 };
39
40 struct walker_data {
41         const char *url;
42         int got_alternates;
43         struct alt_base *alt;
44 };
45
46 static LIST_HEAD(object_queue_head);
47
48 static void fetch_alternates(struct walker *walker, const char *base);
49
50 static void process_object_response(void *callback_data);
51
52 static void start_object_request(struct walker *walker,
53                                  struct object_request *obj_req)
54 {
55         struct active_request_slot *slot;
56         struct http_object_request *req;
57
58         req = new_http_object_request(obj_req->repo->base, obj_req->sha1);
59         if (req == NULL) {
60                 obj_req->state = ABORTED;
61                 return;
62         }
63         obj_req->req = req;
64
65         slot = req->slot;
66         slot->callback_func = process_object_response;
67         slot->callback_data = obj_req;
68
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;
75         }
76 }
77
78 static void finish_object_request(struct object_request *obj_req)
79 {
80         if (finish_http_object_request(obj_req->req))
81                 return;
82
83         if (obj_req->req->rename == 0)
84                 walker_say(obj_req->walker, "got %s\n", sha1_to_hex(obj_req->sha1));
85 }
86
87 static void process_object_response(void *callback_data)
88 {
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;
94
95         process_http_object_request(obj_req->req);
96         obj_req->state = COMPLETE;
97
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;
107                 }
108         }
109
110         finish_object_request(obj_req);
111 }
112
113 static void release_object_request(struct object_request *obj_req)
114 {
115         if (obj_req->req !=NULL && obj_req->req->localfile != -1)
116                 error("fd leakage in release: %d", obj_req->req->localfile);
117
118         list_del(&obj_req->node);
119         free(obj_req);
120 }
121
122 #ifdef USE_CURL_MULTI
123 static int fill_active_slot(struct walker *walker)
124 {
125         struct object_request *obj_req;
126         struct list_head *pos, *tmp, *head = &object_queue_head;
127
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;
136                         }
137                 }
138         }
139         return 0;
140 }
141 #endif
142
143 static void prefetch(struct walker *walker, unsigned char *sha1)
144 {
145         struct object_request *newreq;
146         struct walker_data *data = walker->data;
147
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;
154
155         http_is_verbose = walker->get_verbosely;
156         list_add_tail(&newreq->node, &object_queue_head);
157
158 #ifdef USE_CURL_MULTI
159         fill_active_slots();
160         step_active_slots();
161 #endif
162 }
163
164 static int is_alternate_allowed(const char *url)
165 {
166         const char *protocols[] = {
167                 "http", "https", "ftp", "ftps"
168         };
169         int i;
170
171         for (i = 0; i < ARRAY_SIZE(protocols); i++) {
172                 const char *end;
173                 if (skip_prefix(url, protocols[i], &end) &&
174                     starts_with(end, "://"))
175                         break;
176         }
177
178         if (i >= ARRAY_SIZE(protocols)) {
179                 warning("ignoring alternate with unknown protocol: %s", url);
180                 return 0;
181         }
182         if (!is_transport_allowed(protocols[i], 0)) {
183                 warning("ignoring alternate with restricted protocol: %s", url);
184                 return 0;
185         }
186
187         return 1;
188 }
189
190 static void process_alternates_response(void *callback_data)
191 {
192         struct alternates_request *alt_req =
193                 (struct alternates_request *)callback_data;
194         struct walker *walker = alt_req->walker;
195         struct walker_data *cdata = walker->data;
196         struct active_request_slot *slot = alt_req->slot;
197         struct alt_base *tail = cdata->alt;
198         const char *base = alt_req->base;
199         const char null_byte = '\0';
200         char *data;
201         int i = 0;
202
203         if (alt_req->http_specific) {
204                 if (slot->curl_result != CURLE_OK ||
205                     !alt_req->buffer->len) {
206
207                         /* Try reusing the slot to get non-http alternates */
208                         alt_req->http_specific = 0;
209                         strbuf_reset(alt_req->url);
210                         strbuf_addf(alt_req->url, "%s/objects/info/alternates",
211                                     base);
212                         curl_easy_setopt(slot->curl, CURLOPT_URL,
213                                          alt_req->url->buf);
214                         active_requests++;
215                         slot->in_use = 1;
216                         if (slot->finished != NULL)
217                                 (*slot->finished) = 0;
218                         if (!start_active_slot(slot)) {
219                                 cdata->got_alternates = -1;
220                                 slot->in_use = 0;
221                                 if (slot->finished != NULL)
222                                         (*slot->finished) = 1;
223                         }
224                         return;
225                 }
226         } else if (slot->curl_result != CURLE_OK) {
227                 if (!missing_target(slot)) {
228                         cdata->got_alternates = -1;
229                         return;
230                 }
231         }
232
233         fwrite_buffer((char *)&null_byte, 1, 1, alt_req->buffer);
234         alt_req->buffer->len--;
235         data = alt_req->buffer->buf;
236
237         while (i < alt_req->buffer->len) {
238                 int posn = i;
239                 while (posn < alt_req->buffer->len && data[posn] != '\n')
240                         posn++;
241                 if (data[posn] == '\n') {
242                         int okay = 0;
243                         int serverlen = 0;
244                         struct alt_base *newalt;
245                         if (data[i] == '/') {
246                                 /*
247                                  * This counts
248                                  * http://git.host/pub/scm/linux.git/
249                                  * -----------here^
250                                  * so memcpy(dst, base, serverlen) will
251                                  * copy up to "...git.host".
252                                  */
253                                 const char *colon_ss = strstr(base,"://");
254                                 if (colon_ss) {
255                                         serverlen = (strchr(colon_ss + 3, '/')
256                                                      - base);
257                                         okay = 1;
258                                 }
259                         } else if (!memcmp(data + i, "../", 3)) {
260                                 /*
261                                  * Relative URL; chop the corresponding
262                                  * number of subpath from base (and ../
263                                  * from data), and concatenate the result.
264                                  *
265                                  * The code first drops ../ from data, and
266                                  * then drops one ../ from data and one path
267                                  * from base.  IOW, one extra ../ is dropped
268                                  * from data than path is dropped from base.
269                                  *
270                                  * This is not wrong.  The alternate in
271                                  *     http://git.host/pub/scm/linux.git/
272                                  * to borrow from
273                                  *     http://git.host/pub/scm/linus.git/
274                                  * is ../../linus.git/objects/.  You need
275                                  * two ../../ to borrow from your direct
276                                  * neighbour.
277                                  */
278                                 i += 3;
279                                 serverlen = strlen(base);
280                                 while (i + 2 < posn &&
281                                        !memcmp(data + i, "../", 3)) {
282                                         do {
283                                                 serverlen--;
284                                         } while (serverlen &&
285                                                  base[serverlen - 1] != '/');
286                                         i += 3;
287                                 }
288                                 /* If the server got removed, give up. */
289                                 okay = strchr(base, ':') - base + 3 <
290                                        serverlen;
291                         } else if (alt_req->http_specific) {
292                                 char *colon = strchr(data + i, ':');
293                                 char *slash = strchr(data + i, '/');
294                                 if (colon && slash && colon < data + posn &&
295                                     slash < data + posn && colon < slash) {
296                                         okay = 1;
297                                 }
298                         }
299                         /* skip "objects\n" at end */
300                         if (okay) {
301                                 struct strbuf target = STRBUF_INIT;
302                                 strbuf_add(&target, base, serverlen);
303                                 strbuf_add(&target, data + i, posn - i - 7);
304
305                                 if (is_alternate_allowed(target.buf)) {
306                                         warning("adding alternate object store: %s",
307                                                 target.buf);
308                                         newalt = xmalloc(sizeof(*newalt));
309                                         newalt->next = NULL;
310                                         newalt->base = strbuf_detach(&target, NULL);
311                                         newalt->got_indices = 0;
312                                         newalt->packs = NULL;
313
314                                         while (tail->next != NULL)
315                                                 tail = tail->next;
316                                         tail->next = newalt;
317                                 }
318                         }
319                 }
320                 i = posn + 1;
321         }
322
323         cdata->got_alternates = 1;
324 }
325
326 static void fetch_alternates(struct walker *walker, const char *base)
327 {
328         struct strbuf buffer = STRBUF_INIT;
329         struct strbuf url = STRBUF_INIT;
330         struct active_request_slot *slot;
331         struct alternates_request alt_req;
332         struct walker_data *cdata = walker->data;
333
334         if (http_follow_config != HTTP_FOLLOW_ALWAYS)
335                 return;
336
337         /*
338          * If another request has already started fetching alternates,
339          * wait for them to arrive and return to processing this request's
340          * curl message
341          */
342 #ifdef USE_CURL_MULTI
343         while (cdata->got_alternates == 0) {
344                 step_active_slots();
345         }
346 #endif
347
348         /* Nothing to do if they've already been fetched */
349         if (cdata->got_alternates == 1)
350                 return;
351
352         /* Start the fetch */
353         cdata->got_alternates = 0;
354
355         if (walker->get_verbosely)
356                 fprintf(stderr, "Getting alternates list for %s\n", base);
357
358         strbuf_addf(&url, "%s/objects/info/http-alternates", base);
359
360         /*
361          * Use a callback to process the result, since another request
362          * may fail and need to have alternates loaded before continuing
363          */
364         slot = get_active_slot();
365         slot->callback_func = process_alternates_response;
366         alt_req.walker = walker;
367         slot->callback_data = &alt_req;
368
369         curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
370         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
371         curl_easy_setopt(slot->curl, CURLOPT_URL, url.buf);
372
373         alt_req.base = base;
374         alt_req.url = &url;
375         alt_req.buffer = &buffer;
376         alt_req.http_specific = 1;
377         alt_req.slot = slot;
378
379         if (start_active_slot(slot))
380                 run_active_slot(slot);
381         else
382                 cdata->got_alternates = -1;
383
384         strbuf_release(&buffer);
385         strbuf_release(&url);
386 }
387
388 static int fetch_indices(struct walker *walker, struct alt_base *repo)
389 {
390         int ret;
391
392         if (repo->got_indices)
393                 return 0;
394
395         if (walker->get_verbosely)
396                 fprintf(stderr, "Getting pack list for %s\n", repo->base);
397
398         switch (http_get_info_packs(repo->base, &repo->packs)) {
399         case HTTP_OK:
400         case HTTP_MISSING_TARGET:
401                 repo->got_indices = 1;
402                 ret = 0;
403                 break;
404         default:
405                 repo->got_indices = 0;
406                 ret = -1;
407         }
408
409         return ret;
410 }
411
412 static int http_fetch_pack(struct walker *walker, struct alt_base *repo, unsigned char *sha1)
413 {
414         struct packed_git *target;
415         int ret;
416         struct slot_results results;
417         struct http_pack_request *preq;
418
419         if (fetch_indices(walker, repo))
420                 return -1;
421         target = find_sha1_pack(sha1, repo->packs);
422         if (!target)
423                 return -1;
424
425         if (walker->get_verbosely) {
426                 fprintf(stderr, "Getting pack %s\n",
427                         sha1_to_hex(target->sha1));
428                 fprintf(stderr, " which contains %s\n",
429                         sha1_to_hex(sha1));
430         }
431
432         preq = new_http_pack_request(target, repo->base);
433         if (preq == NULL)
434                 goto abort;
435         preq->lst = &repo->packs;
436         preq->slot->results = &results;
437
438         if (start_active_slot(preq->slot)) {
439                 run_active_slot(preq->slot);
440                 if (results.curl_result != CURLE_OK) {
441                         error("Unable to get pack file %s\n%s", preq->url,
442                               curl_errorstr);
443                         goto abort;
444                 }
445         } else {
446                 error("Unable to start request");
447                 goto abort;
448         }
449
450         ret = finish_http_pack_request(preq);
451         release_http_pack_request(preq);
452         if (ret)
453                 return ret;
454
455         return 0;
456
457 abort:
458         return -1;
459 }
460
461 static void abort_object_request(struct object_request *obj_req)
462 {
463         release_object_request(obj_req);
464 }
465
466 static int fetch_object(struct walker *walker, unsigned char *sha1)
467 {
468         char *hex = sha1_to_hex(sha1);
469         int ret = 0;
470         struct object_request *obj_req = NULL;
471         struct http_object_request *req;
472         struct list_head *pos, *head = &object_queue_head;
473
474         list_for_each(pos, head) {
475                 obj_req = list_entry(pos, struct object_request, node);
476                 if (!hashcmp(obj_req->sha1, sha1))
477                         break;
478         }
479         if (obj_req == NULL)
480                 return error("Couldn't find request for %s in the queue", hex);
481
482         if (has_sha1_file(obj_req->sha1)) {
483                 if (obj_req->req != NULL)
484                         abort_http_object_request(obj_req->req);
485                 abort_object_request(obj_req);
486                 return 0;
487         }
488
489 #ifdef USE_CURL_MULTI
490         while (obj_req->state == WAITING)
491                 step_active_slots();
492 #else
493         start_object_request(walker, obj_req);
494 #endif
495
496         /*
497          * obj_req->req might change when fetching alternates in the callback
498          * process_object_response; therefore, the "shortcut" variable, req,
499          * is used only after we're done with slots.
500          */
501         while (obj_req->state == ACTIVE)
502                 run_active_slot(obj_req->req->slot);
503
504         req = obj_req->req;
505
506         if (req->localfile != -1) {
507                 close(req->localfile);
508                 req->localfile = -1;
509         }
510
511         /*
512          * we turned off CURLOPT_FAILONERROR to avoid losing a
513          * persistent connection and got CURLE_OK.
514          */
515         if (req->http_code >= 300 && req->curl_result == CURLE_OK &&
516                         (starts_with(req->url, "http://") ||
517                          starts_with(req->url, "https://"))) {
518                 req->curl_result = CURLE_HTTP_RETURNED_ERROR;
519                 xsnprintf(req->errorstr, sizeof(req->errorstr),
520                           "HTTP request failed");
521         }
522
523         if (obj_req->state == ABORTED) {
524                 ret = error("Request for %s aborted", hex);
525         } else if (req->curl_result != CURLE_OK &&
526                    req->http_code != 416) {
527                 if (missing_target(req))
528                         ret = -1; /* Be silent, it is probably in a pack. */
529                 else
530                         ret = error("%s (curl_result = %d, http_code = %ld, sha1 = %s)",
531                                     req->errorstr, req->curl_result,
532                                     req->http_code, hex);
533         } else if (req->zret != Z_STREAM_END) {
534                 walker->corrupt_object_found++;
535                 ret = error("File %s (%s) corrupt", hex, req->url);
536         } else if (hashcmp(obj_req->sha1, req->real_sha1)) {
537                 ret = error("File %s has bad hash", hex);
538         } else if (req->rename < 0) {
539                 ret = error("unable to write sha1 filename %s",
540                             sha1_file_name(req->sha1));
541         }
542
543         release_http_object_request(req);
544         release_object_request(obj_req);
545         return ret;
546 }
547
548 static int fetch(struct walker *walker, unsigned char *sha1)
549 {
550         struct walker_data *data = walker->data;
551         struct alt_base *altbase = data->alt;
552
553         if (!fetch_object(walker, sha1))
554                 return 0;
555         while (altbase) {
556                 if (!http_fetch_pack(walker, altbase, sha1))
557                         return 0;
558                 fetch_alternates(walker, data->alt->base);
559                 altbase = altbase->next;
560         }
561         return error("Unable to find %s under %s", sha1_to_hex(sha1),
562                      data->alt->base);
563 }
564
565 static int fetch_ref(struct walker *walker, struct ref *ref)
566 {
567         struct walker_data *data = walker->data;
568         return http_fetch_ref(data->alt->base, ref);
569 }
570
571 static void cleanup(struct walker *walker)
572 {
573         struct walker_data *data = walker->data;
574         struct alt_base *alt, *alt_next;
575
576         if (data) {
577                 alt = data->alt;
578                 while (alt) {
579                         alt_next = alt->next;
580
581                         free(alt->base);
582                         free(alt);
583
584                         alt = alt_next;
585                 }
586                 free(data);
587                 walker->data = NULL;
588         }
589 }
590
591 struct walker *get_http_walker(const char *url)
592 {
593         char *s;
594         struct walker_data *data = xmalloc(sizeof(struct walker_data));
595         struct walker *walker = xmalloc(sizeof(struct walker));
596
597         data->alt = xmalloc(sizeof(*data->alt));
598         data->alt->base = xstrdup(url);
599         for (s = data->alt->base + strlen(data->alt->base) - 1; *s == '/'; --s)
600                 *s = 0;
601
602         data->alt->got_indices = 0;
603         data->alt->packs = NULL;
604         data->alt->next = NULL;
605         data->got_alternates = -1;
606
607         walker->corrupt_object_found = 0;
608         walker->fetch = fetch;
609         walker->fetch_ref = fetch_ref;
610         walker->prefetch = prefetch;
611         walker->cleanup = cleanup;
612         walker->data = data;
613
614 #ifdef USE_CURL_MULTI
615         add_fill_function(walker, (int (*)(void *)) fill_active_slot);
616 #endif
617
618         return walker;
619 }