whitespace cleanup.
[git] / http-fetch.c
1 #include "cache.h"
2 #include "commit.h"
3 #include "pack.h"
4 #include "fetch.h"
5 #include "http.h"
6
7 #define PREV_BUF_SIZE 4096
8 #define RANGE_HEADER_SIZE 30
9
10 static int got_alternates = -1;
11
12 static struct curl_slist *no_pragma_header;
13
14 struct alt_base
15 {
16         char *base;
17         int got_indices;
18         struct packed_git *packs;
19         struct alt_base *next;
20 };
21
22 static struct alt_base *alt = NULL;
23
24 enum object_request_state {
25         WAITING,
26         ABORTED,
27         ACTIVE,
28         COMPLETE,
29 };
30
31 struct object_request
32 {
33         unsigned char sha1[20];
34         struct alt_base *repo;
35         char *url;
36         char filename[PATH_MAX];
37         char tmpfile[PATH_MAX];
38         int local;
39         enum object_request_state state;
40         CURLcode curl_result;
41         char errorstr[CURL_ERROR_SIZE];
42         long http_code;
43         unsigned char real_sha1[20];
44         SHA_CTX c;
45         z_stream stream;
46         int zret;
47         int rename;
48         struct active_request_slot *slot;
49         struct object_request *next;
50 };
51
52 struct alternates_request {
53         char *base;
54         char *url;
55         struct buffer *buffer;
56         struct active_request_slot *slot;
57         int http_specific;
58 };
59
60 static struct object_request *object_queue_head = NULL;
61
62 static size_t fwrite_sha1_file(void *ptr, size_t eltsize, size_t nmemb,
63                                void *data)
64 {
65         unsigned char expn[4096];
66         size_t size = eltsize * nmemb;
67         int posn = 0;
68         struct object_request *obj_req = (struct object_request *)data;
69         do {
70                 ssize_t retval = write(obj_req->local,
71                                        ptr + posn, size - posn);
72                 if (retval < 0)
73                         return posn;
74                 posn += retval;
75         } while (posn < size);
76
77         obj_req->stream.avail_in = size;
78         obj_req->stream.next_in = ptr;
79         do {
80                 obj_req->stream.next_out = expn;
81                 obj_req->stream.avail_out = sizeof(expn);
82                 obj_req->zret = inflate(&obj_req->stream, Z_SYNC_FLUSH);
83                 SHA1_Update(&obj_req->c, expn,
84                             sizeof(expn) - obj_req->stream.avail_out);
85         } while (obj_req->stream.avail_in && obj_req->zret == Z_OK);
86         data_received++;
87         return size;
88 }
89
90 static void fetch_alternates(char *base);
91
92 static void process_object_response(void *callback_data);
93
94 static void start_object_request(struct object_request *obj_req)
95 {
96         char *hex = sha1_to_hex(obj_req->sha1);
97         char prevfile[PATH_MAX];
98         char *url;
99         char *posn;
100         int prevlocal;
101         unsigned char prev_buf[PREV_BUF_SIZE];
102         ssize_t prev_read = 0;
103         long prev_posn = 0;
104         char range[RANGE_HEADER_SIZE];
105         struct curl_slist *range_header = NULL;
106         struct active_request_slot *slot;
107
108         snprintf(prevfile, sizeof(prevfile), "%s.prev", obj_req->filename);
109         unlink(prevfile);
110         rename(obj_req->tmpfile, prevfile);
111         unlink(obj_req->tmpfile);
112
113         if (obj_req->local != -1)
114                 error("fd leakage in start: %d", obj_req->local);
115         obj_req->local = open(obj_req->tmpfile,
116                               O_WRONLY | O_CREAT | O_EXCL, 0666);
117         /* This could have failed due to the "lazy directory creation";
118          * try to mkdir the last path component.
119          */
120         if (obj_req->local < 0 && errno == ENOENT) {
121                 char *dir = strrchr(obj_req->tmpfile, '/');
122                 if (dir) {
123                         *dir = 0;
124                         mkdir(obj_req->tmpfile, 0777);
125                         *dir = '/';
126                 }
127                 obj_req->local = open(obj_req->tmpfile,
128                                       O_WRONLY | O_CREAT | O_EXCL, 0666);
129         }
130
131         if (obj_req->local < 0) {
132                 obj_req->state = ABORTED;
133                 error("Couldn't create temporary file %s for %s: %s\n",
134                       obj_req->tmpfile, obj_req->filename, strerror(errno));
135                 return;
136         }
137
138         memset(&obj_req->stream, 0, sizeof(obj_req->stream));
139
140         inflateInit(&obj_req->stream);
141
142         SHA1_Init(&obj_req->c);
143
144         url = xmalloc(strlen(obj_req->repo->base) + 50);
145         obj_req->url = xmalloc(strlen(obj_req->repo->base) + 50);
146         strcpy(url, obj_req->repo->base);
147         posn = url + strlen(obj_req->repo->base);
148         strcpy(posn, "objects/");
149         posn += 8;
150         memcpy(posn, hex, 2);
151         posn += 2;
152         *(posn++) = '/';
153         strcpy(posn, hex + 2);
154         strcpy(obj_req->url, url);
155
156         /* If a previous temp file is present, process what was already
157            fetched. */
158         prevlocal = open(prevfile, O_RDONLY);
159         if (prevlocal != -1) {
160                 do {
161                         prev_read = read(prevlocal, prev_buf, PREV_BUF_SIZE);
162                         if (prev_read>0) {
163                                 if (fwrite_sha1_file(prev_buf,
164                                                      1,
165                                                      prev_read,
166                                                      obj_req) == prev_read) {
167                                         prev_posn += prev_read;
168                                 } else {
169                                         prev_read = -1;
170                                 }
171                         }
172                 } while (prev_read > 0);
173                 close(prevlocal);
174         }
175         unlink(prevfile);
176
177         /* Reset inflate/SHA1 if there was an error reading the previous temp
178            file; also rewind to the beginning of the local file. */
179         if (prev_read == -1) {
180                 memset(&obj_req->stream, 0, sizeof(obj_req->stream));
181                 inflateInit(&obj_req->stream);
182                 SHA1_Init(&obj_req->c);
183                 if (prev_posn>0) {
184                         prev_posn = 0;
185                         lseek(obj_req->local, SEEK_SET, 0);
186                         ftruncate(obj_req->local, 0);
187                 }
188         }
189
190         slot = get_active_slot();
191         slot->callback_func = process_object_response;
192         slot->callback_data = obj_req;
193         obj_req->slot = slot;
194
195         curl_easy_setopt(slot->curl, CURLOPT_FILE, obj_req);
196         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
197         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, obj_req->errorstr);
198         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
199         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
200
201         /* If we have successfully processed data from a previous fetch
202            attempt, only fetch the data we don't already have. */
203         if (prev_posn>0) {
204                 if (get_verbosely)
205                         fprintf(stderr,
206                                 "Resuming fetch of object %s at byte %ld\n",
207                                 hex, prev_posn);
208                 sprintf(range, "Range: bytes=%ld-", prev_posn);
209                 range_header = curl_slist_append(range_header, range);
210                 curl_easy_setopt(slot->curl,
211                                  CURLOPT_HTTPHEADER, range_header);
212         }
213
214         /* Try to get the request started, abort the request on error */
215         obj_req->state = ACTIVE;
216         if (!start_active_slot(slot)) {
217                 obj_req->state = ABORTED;
218                 obj_req->slot = NULL;
219                 close(obj_req->local); obj_req->local = -1;
220                 free(obj_req->url);
221                 return;
222         }
223 }
224
225 static void finish_object_request(struct object_request *obj_req)
226 {
227         struct stat st;
228
229         fchmod(obj_req->local, 0444);
230         close(obj_req->local); obj_req->local = -1;
231
232         if (obj_req->http_code == 416) {
233                 fprintf(stderr, "Warning: requested range invalid; we may already have all the data.\n");
234         } else if (obj_req->curl_result != CURLE_OK) {
235                 if (stat(obj_req->tmpfile, &st) == 0)
236                         if (st.st_size == 0)
237                                 unlink(obj_req->tmpfile);
238                 return;
239         }
240
241         inflateEnd(&obj_req->stream);
242         SHA1_Final(obj_req->real_sha1, &obj_req->c);
243         if (obj_req->zret != Z_STREAM_END) {
244                 unlink(obj_req->tmpfile);
245                 return;
246         }
247         if (memcmp(obj_req->sha1, obj_req->real_sha1, 20)) {
248                 unlink(obj_req->tmpfile);
249                 return;
250         }
251         obj_req->rename =
252                 move_temp_to_file(obj_req->tmpfile, obj_req->filename);
253
254         if (obj_req->rename == 0)
255                 pull_say("got %s\n", sha1_to_hex(obj_req->sha1));
256 }
257
258 static void process_object_response(void *callback_data)
259 {
260         struct object_request *obj_req =
261                 (struct object_request *)callback_data;
262
263         obj_req->curl_result = obj_req->slot->curl_result;
264         obj_req->http_code = obj_req->slot->http_code;
265         obj_req->slot = NULL;
266         obj_req->state = COMPLETE;
267
268         /* Use alternates if necessary */
269         if (obj_req->http_code == 404 ||
270             obj_req->curl_result == CURLE_FILE_COULDNT_READ_FILE) {
271                 fetch_alternates(alt->base);
272                 if (obj_req->repo->next != NULL) {
273                         obj_req->repo =
274                                 obj_req->repo->next;
275                         close(obj_req->local);
276                         obj_req->local = -1;
277                         start_object_request(obj_req);
278                         return;
279                 }
280         }
281
282         finish_object_request(obj_req);
283 }
284
285 static void release_object_request(struct object_request *obj_req)
286 {
287         struct object_request *entry = object_queue_head;
288
289         if (obj_req->local != -1)
290                 error("fd leakage in release: %d", obj_req->local);
291         if (obj_req == object_queue_head) {
292                 object_queue_head = obj_req->next;
293         } else {
294                 while (entry->next != NULL && entry->next != obj_req)
295                         entry = entry->next;
296                 if (entry->next == obj_req)
297                         entry->next = entry->next->next;
298         }
299
300         free(obj_req->url);
301         free(obj_req);
302 }
303
304 #ifdef USE_CURL_MULTI
305 void fill_active_slots(void)
306 {
307         struct object_request *obj_req = object_queue_head;
308         struct active_request_slot *slot = active_queue_head;
309         int num_transfers;
310
311         while (active_requests < max_requests && obj_req != NULL) {
312                 if (obj_req->state == WAITING) {
313                         if (has_sha1_file(obj_req->sha1))
314                                 release_object_request(obj_req);
315                         else
316                                 start_object_request(obj_req);
317                         curl_multi_perform(curlm, &num_transfers);
318                 }
319                 obj_req = obj_req->next;
320         }
321
322         while (slot != NULL) {
323                 if (!slot->in_use && slot->curl != NULL) {
324                         curl_easy_cleanup(slot->curl);
325                         slot->curl = NULL;
326                 }
327                 slot = slot->next;
328         }
329 }
330 #endif
331
332 void prefetch(unsigned char *sha1)
333 {
334         struct object_request *newreq;
335         struct object_request *tail;
336         char *filename = sha1_file_name(sha1);
337
338         newreq = xmalloc(sizeof(*newreq));
339         memcpy(newreq->sha1, sha1, 20);
340         newreq->repo = alt;
341         newreq->url = NULL;
342         newreq->local = -1;
343         newreq->state = WAITING;
344         snprintf(newreq->filename, sizeof(newreq->filename), "%s", filename);
345         snprintf(newreq->tmpfile, sizeof(newreq->tmpfile),
346                  "%s.temp", filename);
347         newreq->next = NULL;
348
349         if (object_queue_head == NULL) {
350                 object_queue_head = newreq;
351         } else {
352                 tail = object_queue_head;
353                 while (tail->next != NULL) {
354                         tail = tail->next;
355                 }
356                 tail->next = newreq;
357         }
358
359 #ifdef USE_CURL_MULTI
360         fill_active_slots();
361         step_active_slots();
362 #endif
363 }
364
365 static int fetch_index(struct alt_base *repo, unsigned char *sha1)
366 {
367         char *hex = sha1_to_hex(sha1);
368         char *filename;
369         char *url;
370         char tmpfile[PATH_MAX];
371         long prev_posn = 0;
372         char range[RANGE_HEADER_SIZE];
373         struct curl_slist *range_header = NULL;
374
375         FILE *indexfile;
376         struct active_request_slot *slot;
377         struct slot_results results;
378
379         if (has_pack_index(sha1))
380                 return 0;
381
382         if (get_verbosely)
383                 fprintf(stderr, "Getting index for pack %s\n", hex);
384
385         url = xmalloc(strlen(repo->base) + 64);
386         sprintf(url, "%s/objects/pack/pack-%s.idx", repo->base, hex);
387
388         filename = sha1_pack_index_name(sha1);
389         snprintf(tmpfile, sizeof(tmpfile), "%s.temp", filename);
390         indexfile = fopen(tmpfile, "a");
391         if (!indexfile)
392                 return error("Unable to open local file %s for pack index",
393                              filename);
394
395         slot = get_active_slot();
396         slot->results = &results;
397         curl_easy_setopt(slot->curl, CURLOPT_FILE, indexfile);
398         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
399         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
400         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
401         slot->local = indexfile;
402
403         /* If there is data present from a previous transfer attempt,
404            resume where it left off */
405         prev_posn = ftell(indexfile);
406         if (prev_posn>0) {
407                 if (get_verbosely)
408                         fprintf(stderr,
409                                 "Resuming fetch of index for pack %s at byte %ld\n",
410                                 hex, prev_posn);
411                 sprintf(range, "Range: bytes=%ld-", prev_posn);
412                 range_header = curl_slist_append(range_header, range);
413                 curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, range_header);
414         }
415
416         if (start_active_slot(slot)) {
417                 run_active_slot(slot);
418                 if (results.curl_result != CURLE_OK) {
419                         fclose(indexfile);
420                         return error("Unable to get pack index %s\n%s", url,
421                                      curl_errorstr);
422                 }
423         } else {
424                 fclose(indexfile);
425                 return error("Unable to start request");
426         }
427
428         fclose(indexfile);
429
430         return move_temp_to_file(tmpfile, filename);
431 }
432
433 static int setup_index(struct alt_base *repo, unsigned char *sha1)
434 {
435         struct packed_git *new_pack;
436         if (has_pack_file(sha1))
437                 return 0; // don't list this as something we can get
438
439         if (fetch_index(repo, sha1))
440                 return -1;
441
442         new_pack = parse_pack_index(sha1);
443         new_pack->next = repo->packs;
444         repo->packs = new_pack;
445         return 0;
446 }
447
448 static void process_alternates_response(void *callback_data)
449 {
450         struct alternates_request *alt_req =
451                 (struct alternates_request *)callback_data;
452         struct active_request_slot *slot = alt_req->slot;
453         struct alt_base *tail = alt;
454         char *base = alt_req->base;
455         static const char null_byte = '\0';
456         char *data;
457         int i = 0;
458
459         if (alt_req->http_specific) {
460                 if (slot->curl_result != CURLE_OK ||
461                     !alt_req->buffer->posn) {
462
463                         /* Try reusing the slot to get non-http alternates */
464                         alt_req->http_specific = 0;
465                         sprintf(alt_req->url, "%s/objects/info/alternates",
466                                 base);
467                         curl_easy_setopt(slot->curl, CURLOPT_URL,
468                                          alt_req->url);
469                         active_requests++;
470                         slot->in_use = 1;
471                         if (start_active_slot(slot)) {
472                                 return;
473                         } else {
474                                 got_alternates = -1;
475                                 slot->in_use = 0;
476                                 return;
477                         }
478                 }
479         } else if (slot->curl_result != CURLE_OK) {
480                 if (slot->http_code != 404 &&
481                     slot->curl_result != CURLE_FILE_COULDNT_READ_FILE) {
482                         got_alternates = -1;
483                         return;
484                 }
485         }
486
487         fwrite_buffer(&null_byte, 1, 1, alt_req->buffer);
488         alt_req->buffer->posn--;
489         data = alt_req->buffer->buffer;
490
491         while (i < alt_req->buffer->posn) {
492                 int posn = i;
493                 while (posn < alt_req->buffer->posn && data[posn] != '\n')
494                         posn++;
495                 if (data[posn] == '\n') {
496                         int okay = 0;
497                         int serverlen = 0;
498                         struct alt_base *newalt;
499                         char *target = NULL;
500                         if (data[i] == '/') {
501                                 serverlen = strchr(base + 8, '/') - base;
502                                 okay = 1;
503                         } else if (!memcmp(data + i, "../", 3)) {
504                                 i += 3;
505                                 serverlen = strlen(base);
506                                 while (i + 2 < posn &&
507                                        !memcmp(data + i, "../", 3)) {
508                                         do {
509                                                 serverlen--;
510                                         } while (serverlen &&
511                                                  base[serverlen - 1] != '/');
512                                         i += 3;
513                                 }
514                                 // If the server got removed, give up.
515                                 okay = strchr(base, ':') - base + 3 <
516                                         serverlen;
517                         } else if (alt_req->http_specific) {
518                                 char *colon = strchr(data + i, ':');
519                                 char *slash = strchr(data + i, '/');
520                                 if (colon && slash && colon < data + posn &&
521                                     slash < data + posn && colon < slash) {
522                                         okay = 1;
523                                 }
524                         }
525                         // skip 'objects' at end
526                         if (okay) {
527                                 target = xmalloc(serverlen + posn - i - 6);
528                                 strncpy(target, base, serverlen);
529                                 strncpy(target + serverlen, data + i,
530                                         posn - i - 7);
531                                 target[serverlen + posn - i - 7] = '\0';
532                                 if (get_verbosely)
533                                         fprintf(stderr,
534                                                 "Also look at %s\n", target);
535                                 newalt = xmalloc(sizeof(*newalt));
536                                 newalt->next = NULL;
537                                 newalt->base = target;
538                                 newalt->got_indices = 0;
539                                 newalt->packs = NULL;
540                                 while (tail->next != NULL)
541                                         tail = tail->next;
542                                 tail->next = newalt;
543                         }
544                 }
545                 i = posn + 1;
546         }
547
548         got_alternates = 1;
549 }
550
551 static void fetch_alternates(char *base)
552 {
553         struct buffer buffer;
554         char *url;
555         char *data;
556         struct active_request_slot *slot;
557         struct alternates_request alt_req;
558
559         /* If another request has already started fetching alternates,
560            wait for them to arrive and return to processing this request's
561            curl message */
562 #ifdef USE_CURL_MULTI
563         while (got_alternates == 0) {
564                 step_active_slots();
565         }
566 #endif
567
568         /* Nothing to do if they've already been fetched */
569         if (got_alternates == 1)
570                 return;
571
572         /* Start the fetch */
573         got_alternates = 0;
574
575         data = xmalloc(4096);
576         buffer.size = 4096;
577         buffer.posn = 0;
578         buffer.buffer = data;
579
580         if (get_verbosely)
581                 fprintf(stderr, "Getting alternates list for %s\n", base);
582
583         url = xmalloc(strlen(base) + 31);
584         sprintf(url, "%s/objects/info/http-alternates", base);
585
586         /* Use a callback to process the result, since another request
587            may fail and need to have alternates loaded before continuing */
588         slot = get_active_slot();
589         slot->callback_func = process_alternates_response;
590         slot->callback_data = &alt_req;
591
592         curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
593         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
594         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
595
596         alt_req.base = base;
597         alt_req.url = url;
598         alt_req.buffer = &buffer;
599         alt_req.http_specific = 1;
600         alt_req.slot = slot;
601
602         if (start_active_slot(slot))
603                 run_active_slot(slot);
604         else
605                 got_alternates = -1;
606
607         free(data);
608         free(url);
609 }
610
611 static int fetch_indices(struct alt_base *repo)
612 {
613         unsigned char sha1[20];
614         char *url;
615         struct buffer buffer;
616         char *data;
617         int i = 0;
618
619         struct active_request_slot *slot;
620         struct slot_results results;
621
622         if (repo->got_indices)
623                 return 0;
624
625         data = xmalloc(4096);
626         buffer.size = 4096;
627         buffer.posn = 0;
628         buffer.buffer = data;
629
630         if (get_verbosely)
631                 fprintf(stderr, "Getting pack list for %s\n", repo->base);
632
633         url = xmalloc(strlen(repo->base) + 21);
634         sprintf(url, "%s/objects/info/packs", repo->base);
635
636         slot = get_active_slot();
637         slot->results = &results;
638         curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
639         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
640         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
641         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
642         if (start_active_slot(slot)) {
643                 run_active_slot(slot);
644                 if (results.curl_result != CURLE_OK) {
645                         if (results.http_code == 404 ||
646                             results.curl_result == CURLE_FILE_COULDNT_READ_FILE) {
647                                 repo->got_indices = 1;
648                                 free(buffer.buffer);
649                                 return 0;
650                         } else {
651                                 repo->got_indices = 0;
652                                 free(buffer.buffer);
653                                 return error("%s", curl_errorstr);
654                         }
655                 }
656         } else {
657                 repo->got_indices = 0;
658                 free(buffer.buffer);
659                 return error("Unable to start request");
660         }
661
662         data = buffer.buffer;
663         while (i < buffer.posn) {
664                 switch (data[i]) {
665                 case 'P':
666                         i++;
667                         if (i + 52 <= buffer.posn &&
668                             !strncmp(data + i, " pack-", 6) &&
669                             !strncmp(data + i + 46, ".pack\n", 6)) {
670                                 get_sha1_hex(data + i + 6, sha1);
671                                 setup_index(repo, sha1);
672                                 i += 51;
673                                 break;
674                         }
675                 default:
676                         while (i < buffer.posn && data[i] != '\n')
677                                 i++;
678                 }
679                 i++;
680         }
681
682         free(buffer.buffer);
683         repo->got_indices = 1;
684         return 0;
685 }
686
687 static int fetch_pack(struct alt_base *repo, unsigned char *sha1)
688 {
689         char *url;
690         struct packed_git *target;
691         struct packed_git **lst;
692         FILE *packfile;
693         char *filename;
694         char tmpfile[PATH_MAX];
695         int ret;
696         long prev_posn = 0;
697         char range[RANGE_HEADER_SIZE];
698         struct curl_slist *range_header = NULL;
699
700         struct active_request_slot *slot;
701         struct slot_results results;
702
703         if (fetch_indices(repo))
704                 return -1;
705         target = find_sha1_pack(sha1, repo->packs);
706         if (!target)
707                 return -1;
708
709         if (get_verbosely) {
710                 fprintf(stderr, "Getting pack %s\n",
711                         sha1_to_hex(target->sha1));
712                 fprintf(stderr, " which contains %s\n",
713                         sha1_to_hex(sha1));
714         }
715
716         url = xmalloc(strlen(repo->base) + 65);
717         sprintf(url, "%s/objects/pack/pack-%s.pack",
718                 repo->base, sha1_to_hex(target->sha1));
719
720         filename = sha1_pack_name(target->sha1);
721         snprintf(tmpfile, sizeof(tmpfile), "%s.temp", filename);
722         packfile = fopen(tmpfile, "a");
723         if (!packfile)
724                 return error("Unable to open local file %s for pack",
725                              filename);
726
727         slot = get_active_slot();
728         slot->results = &results;
729         curl_easy_setopt(slot->curl, CURLOPT_FILE, packfile);
730         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
731         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
732         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
733         slot->local = packfile;
734
735         /* If there is data present from a previous transfer attempt,
736            resume where it left off */
737         prev_posn = ftell(packfile);
738         if (prev_posn>0) {
739                 if (get_verbosely)
740                         fprintf(stderr,
741                                 "Resuming fetch of pack %s at byte %ld\n",
742                                 sha1_to_hex(target->sha1), prev_posn);
743                 sprintf(range, "Range: bytes=%ld-", prev_posn);
744                 range_header = curl_slist_append(range_header, range);
745                 curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, range_header);
746         }
747
748         if (start_active_slot(slot)) {
749                 run_active_slot(slot);
750                 if (results.curl_result != CURLE_OK) {
751                         fclose(packfile);
752                         return error("Unable to get pack file %s\n%s", url,
753                                      curl_errorstr);
754                 }
755         } else {
756                 fclose(packfile);
757                 return error("Unable to start request");
758         }
759
760         fclose(packfile);
761
762         ret = move_temp_to_file(tmpfile, filename);
763         if (ret)
764                 return ret;
765
766         lst = &repo->packs;
767         while (*lst != target)
768                 lst = &((*lst)->next);
769         *lst = (*lst)->next;
770
771         if (verify_pack(target, 0))
772                 return -1;
773         install_packed_git(target);
774
775         return 0;
776 }
777
778 static int fetch_object(struct alt_base *repo, unsigned char *sha1)
779 {
780         char *hex = sha1_to_hex(sha1);
781         int ret = 0;
782         struct object_request *obj_req = object_queue_head;
783
784         while (obj_req != NULL && memcmp(obj_req->sha1, sha1, 20))
785                 obj_req = obj_req->next;
786         if (obj_req == NULL)
787                 return error("Couldn't find request for %s in the queue", hex);
788
789         if (has_sha1_file(obj_req->sha1)) {
790                 release_object_request(obj_req);
791                 return 0;
792         }
793
794 #ifdef USE_CURL_MULTI
795         while (obj_req->state == WAITING) {
796                 step_active_slots();
797         }
798 #else
799         start_object_request(obj_req);
800 #endif
801
802         while (obj_req->state == ACTIVE) {
803                 run_active_slot(obj_req->slot);
804         }
805         if (obj_req->local != -1) {
806                 close(obj_req->local); obj_req->local = -1;
807         }
808
809         if (obj_req->state == ABORTED) {
810                 ret = error("Request for %s aborted", hex);
811         } else if (obj_req->curl_result != CURLE_OK &&
812                    obj_req->http_code != 416) {
813                 if (obj_req->http_code == 404 ||
814                     obj_req->curl_result == CURLE_FILE_COULDNT_READ_FILE)
815                         ret = -1; /* Be silent, it is probably in a pack. */
816                 else
817                         ret = error("%s (curl_result = %d, http_code = %ld, sha1 = %s)",
818                                     obj_req->errorstr, obj_req->curl_result,
819                                     obj_req->http_code, hex);
820         } else if (obj_req->zret != Z_STREAM_END) {
821                 ret = error("File %s (%s) corrupt\n", hex, obj_req->url);
822         } else if (memcmp(obj_req->sha1, obj_req->real_sha1, 20)) {
823                 ret = error("File %s has bad hash\n", hex);
824         } else if (obj_req->rename < 0) {
825                 ret = error("unable to write sha1 filename %s: %s",
826                             obj_req->filename,
827                             strerror(obj_req->rename));
828         }
829
830         release_object_request(obj_req);
831         return ret;
832 }
833
834 int fetch(unsigned char *sha1)
835 {
836         struct alt_base *altbase = alt;
837
838         if (!fetch_object(altbase, sha1))
839                 return 0;
840         while (altbase) {
841                 if (!fetch_pack(altbase, sha1))
842                         return 0;
843                 fetch_alternates(alt->base);
844                 altbase = altbase->next;
845         }
846         return error("Unable to find %s under %s\n", sha1_to_hex(sha1),
847                      alt->base);
848 }
849
850 static inline int needs_quote(int ch)
851 {
852         switch (ch) {
853         case '/': case '-': case '.':
854         case 'A'...'Z': case 'a'...'z': case '0'...'9':
855                 return 0;
856         default:
857                 return 1;
858         }
859 }
860
861 static inline int hex(int v)
862 {
863         if (v < 10) return '0' + v;
864         else return 'A' + v - 10;
865 }
866
867 static char *quote_ref_url(const char *base, const char *ref)
868 {
869         const char *cp;
870         char *dp, *qref;
871         int len, baselen, ch;
872
873         baselen = strlen(base);
874         len = baselen + 6; /* "refs/" + NUL */
875         for (cp = ref; (ch = *cp) != 0; cp++, len++)
876                 if (needs_quote(ch))
877                         len += 2; /* extra two hex plus replacement % */
878         qref = xmalloc(len);
879         memcpy(qref, base, baselen);
880         memcpy(qref + baselen, "refs/", 5);
881         for (cp = ref, dp = qref + baselen + 5; (ch = *cp) != 0; cp++) {
882                 if (needs_quote(ch)) {
883                         *dp++ = '%';
884                         *dp++ = hex((ch >> 4) & 0xF);
885                         *dp++ = hex(ch & 0xF);
886                 }
887                 else
888                         *dp++ = ch;
889         }
890         *dp = 0;
891
892         return qref;
893 }
894
895 int fetch_ref(char *ref, unsigned char *sha1)
896 {
897         char *url;
898         char hex[42];
899         struct buffer buffer;
900         char *base = alt->base;
901         struct active_request_slot *slot;
902         struct slot_results results;
903         buffer.size = 41;
904         buffer.posn = 0;
905         buffer.buffer = hex;
906         hex[41] = '\0';
907
908         url = quote_ref_url(base, ref);
909         slot = get_active_slot();
910         slot->results = &results;
911         curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
912         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
913         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
914         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
915         if (start_active_slot(slot)) {
916                 run_active_slot(slot);
917                 if (results.curl_result != CURLE_OK)
918                         return error("Couldn't get %s for %s\n%s",
919                                      url, ref, curl_errorstr);
920         } else {
921                 return error("Unable to start request");
922         }
923
924         hex[40] = '\0';
925         get_sha1_hex(hex, sha1);
926         return 0;
927 }
928
929 int main(int argc, char **argv)
930 {
931         char *commit_id;
932         char *url;
933         int arg = 1;
934         int rc = 0;
935
936         setup_git_directory();
937
938         while (arg < argc && argv[arg][0] == '-') {
939                 if (argv[arg][1] == 't') {
940                         get_tree = 1;
941                 } else if (argv[arg][1] == 'c') {
942                         get_history = 1;
943                 } else if (argv[arg][1] == 'a') {
944                         get_all = 1;
945                         get_tree = 1;
946                         get_history = 1;
947                 } else if (argv[arg][1] == 'v') {
948                         get_verbosely = 1;
949                 } else if (argv[arg][1] == 'w') {
950                         write_ref = argv[arg + 1];
951                         arg++;
952                 } else if (!strcmp(argv[arg], "--recover")) {
953                         get_recover = 1;
954                 }
955                 arg++;
956         }
957         if (argc < arg + 2) {
958                 usage("git-http-fetch [-c] [-t] [-a] [-d] [-v] [--recover] [-w ref] commit-id url");
959                 return 1;
960         }
961         commit_id = argv[arg];
962         url = argv[arg + 1];
963
964         http_init();
965
966         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
967
968         alt = xmalloc(sizeof(*alt));
969         alt->base = url;
970         alt->got_indices = 0;
971         alt->packs = NULL;
972         alt->next = NULL;
973
974         if (pull(commit_id))
975                 rc = 1;
976
977         curl_slist_free_all(no_pragma_header);
978
979         http_cleanup();
980
981         return rc;
982 }