ls-remote: pass ref prefixes when requesting a remote's refs
[git] / upload-pack.c
1 #include "cache.h"
2 #include "config.h"
3 #include "refs.h"
4 #include "pkt-line.h"
5 #include "sideband.h"
6 #include "tag.h"
7 #include "object.h"
8 #include "commit.h"
9 #include "diff.h"
10 #include "revision.h"
11 #include "list-objects.h"
12 #include "run-command.h"
13 #include "connect.h"
14 #include "sigchain.h"
15 #include "version.h"
16 #include "string-list.h"
17 #include "argv-array.h"
18 #include "prio-queue.h"
19 #include "protocol.h"
20 #include "upload-pack.h"
21
22 /* Remember to update object flag allocation in object.h */
23 #define THEY_HAVE       (1u << 11)
24 #define OUR_REF         (1u << 12)
25 #define WANTED          (1u << 13)
26 #define COMMON_KNOWN    (1u << 14)
27 #define REACHABLE       (1u << 15)
28
29 #define SHALLOW         (1u << 16)
30 #define NOT_SHALLOW     (1u << 17)
31 #define CLIENT_SHALLOW  (1u << 18)
32 #define HIDDEN_REF      (1u << 19)
33
34 static timestamp_t oldest_have;
35
36 static int deepen_relative;
37 static int multi_ack;
38 static int no_done;
39 static int use_thin_pack, use_ofs_delta, use_include_tag;
40 static int no_progress, daemon_mode;
41 /* Allow specifying sha1 if it is a ref tip. */
42 #define ALLOW_TIP_SHA1  01
43 /* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
44 #define ALLOW_REACHABLE_SHA1    02
45 /* Allow request of any sha1. Implies ALLOW_TIP_SHA1 and ALLOW_REACHABLE_SHA1. */
46 #define ALLOW_ANY_SHA1  07
47 static unsigned int allow_unadvertised_object_request;
48 static int shallow_nr;
49 static struct object_array have_obj;
50 static struct object_array want_obj;
51 static struct object_array extra_edge_obj;
52 static unsigned int timeout;
53 static int keepalive = 5;
54 /* 0 for no sideband,
55  * otherwise maximum packet size (up to 65520 bytes).
56  */
57 static int use_sideband;
58 static int stateless_rpc;
59 static const char *pack_objects_hook;
60
61 static void reset_timeout(void)
62 {
63         alarm(timeout);
64 }
65
66 static void send_client_data(int fd, const char *data, ssize_t sz)
67 {
68         if (use_sideband) {
69                 send_sideband(1, fd, data, sz, use_sideband);
70                 return;
71         }
72         if (fd == 3)
73                 /* emergency quit */
74                 fd = 2;
75         if (fd == 2) {
76                 /* XXX: are we happy to lose stuff here? */
77                 xwrite(fd, data, sz);
78                 return;
79         }
80         write_or_die(fd, data, sz);
81 }
82
83 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
84 {
85         FILE *fp = cb_data;
86         if (graft->nr_parent == -1)
87                 fprintf(fp, "--shallow %s\n", oid_to_hex(&graft->oid));
88         return 0;
89 }
90
91 static void create_pack_file(void)
92 {
93         struct child_process pack_objects = CHILD_PROCESS_INIT;
94         char data[8193], progress[128];
95         char abort_msg[] = "aborting due to possible repository "
96                 "corruption on the remote side.";
97         int buffered = -1;
98         ssize_t sz;
99         int i;
100         FILE *pipe_fd;
101
102         if (!pack_objects_hook)
103                 pack_objects.git_cmd = 1;
104         else {
105                 argv_array_push(&pack_objects.args, pack_objects_hook);
106                 argv_array_push(&pack_objects.args, "git");
107                 pack_objects.use_shell = 1;
108         }
109
110         if (shallow_nr) {
111                 argv_array_push(&pack_objects.args, "--shallow-file");
112                 argv_array_push(&pack_objects.args, "");
113         }
114         argv_array_push(&pack_objects.args, "pack-objects");
115         argv_array_push(&pack_objects.args, "--revs");
116         if (use_thin_pack)
117                 argv_array_push(&pack_objects.args, "--thin");
118
119         argv_array_push(&pack_objects.args, "--stdout");
120         if (shallow_nr)
121                 argv_array_push(&pack_objects.args, "--shallow");
122         if (!no_progress)
123                 argv_array_push(&pack_objects.args, "--progress");
124         if (use_ofs_delta)
125                 argv_array_push(&pack_objects.args, "--delta-base-offset");
126         if (use_include_tag)
127                 argv_array_push(&pack_objects.args, "--include-tag");
128
129         pack_objects.in = -1;
130         pack_objects.out = -1;
131         pack_objects.err = -1;
132
133         if (start_command(&pack_objects))
134                 die("git upload-pack: unable to fork git-pack-objects");
135
136         pipe_fd = xfdopen(pack_objects.in, "w");
137
138         if (shallow_nr)
139                 for_each_commit_graft(write_one_shallow, pipe_fd);
140
141         for (i = 0; i < want_obj.nr; i++)
142                 fprintf(pipe_fd, "%s\n",
143                         oid_to_hex(&want_obj.objects[i].item->oid));
144         fprintf(pipe_fd, "--not\n");
145         for (i = 0; i < have_obj.nr; i++)
146                 fprintf(pipe_fd, "%s\n",
147                         oid_to_hex(&have_obj.objects[i].item->oid));
148         for (i = 0; i < extra_edge_obj.nr; i++)
149                 fprintf(pipe_fd, "%s\n",
150                         oid_to_hex(&extra_edge_obj.objects[i].item->oid));
151         fprintf(pipe_fd, "\n");
152         fflush(pipe_fd);
153         fclose(pipe_fd);
154
155         /* We read from pack_objects.err to capture stderr output for
156          * progress bar, and pack_objects.out to capture the pack data.
157          */
158
159         while (1) {
160                 struct pollfd pfd[2];
161                 int pe, pu, pollsize;
162                 int ret;
163
164                 reset_timeout();
165
166                 pollsize = 0;
167                 pe = pu = -1;
168
169                 if (0 <= pack_objects.out) {
170                         pfd[pollsize].fd = pack_objects.out;
171                         pfd[pollsize].events = POLLIN;
172                         pu = pollsize;
173                         pollsize++;
174                 }
175                 if (0 <= pack_objects.err) {
176                         pfd[pollsize].fd = pack_objects.err;
177                         pfd[pollsize].events = POLLIN;
178                         pe = pollsize;
179                         pollsize++;
180                 }
181
182                 if (!pollsize)
183                         break;
184
185                 ret = poll(pfd, pollsize,
186                         keepalive < 0 ? -1 : 1000 * keepalive);
187
188                 if (ret < 0) {
189                         if (errno != EINTR) {
190                                 error_errno("poll failed, resuming");
191                                 sleep(1);
192                         }
193                         continue;
194                 }
195                 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
196                         /* Status ready; we ship that in the side-band
197                          * or dump to the standard error.
198                          */
199                         sz = xread(pack_objects.err, progress,
200                                   sizeof(progress));
201                         if (0 < sz)
202                                 send_client_data(2, progress, sz);
203                         else if (sz == 0) {
204                                 close(pack_objects.err);
205                                 pack_objects.err = -1;
206                         }
207                         else
208                                 goto fail;
209                         /* give priority to status messages */
210                         continue;
211                 }
212                 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
213                         /* Data ready; we keep the last byte to ourselves
214                          * in case we detect broken rev-list, so that we
215                          * can leave the stream corrupted.  This is
216                          * unfortunate -- unpack-objects would happily
217                          * accept a valid packdata with trailing garbage,
218                          * so appending garbage after we pass all the
219                          * pack data is not good enough to signal
220                          * breakage to downstream.
221                          */
222                         char *cp = data;
223                         ssize_t outsz = 0;
224                         if (0 <= buffered) {
225                                 *cp++ = buffered;
226                                 outsz++;
227                         }
228                         sz = xread(pack_objects.out, cp,
229                                   sizeof(data) - outsz);
230                         if (0 < sz)
231                                 ;
232                         else if (sz == 0) {
233                                 close(pack_objects.out);
234                                 pack_objects.out = -1;
235                         }
236                         else
237                                 goto fail;
238                         sz += outsz;
239                         if (1 < sz) {
240                                 buffered = data[sz-1] & 0xFF;
241                                 sz--;
242                         }
243                         else
244                                 buffered = -1;
245                         send_client_data(1, data, sz);
246                 }
247
248                 /*
249                  * We hit the keepalive timeout without saying anything; send
250                  * an empty message on the data sideband just to let the other
251                  * side know we're still working on it, but don't have any data
252                  * yet.
253                  *
254                  * If we don't have a sideband channel, there's no room in the
255                  * protocol to say anything, so those clients are just out of
256                  * luck.
257                  */
258                 if (!ret && use_sideband) {
259                         static const char buf[] = "0005\1";
260                         write_or_die(1, buf, 5);
261                 }
262         }
263
264         if (finish_command(&pack_objects)) {
265                 error("git upload-pack: git-pack-objects died with error.");
266                 goto fail;
267         }
268
269         /* flush the data */
270         if (0 <= buffered) {
271                 data[0] = buffered;
272                 send_client_data(1, data, 1);
273                 fprintf(stderr, "flushed.\n");
274         }
275         if (use_sideband)
276                 packet_flush(1);
277         return;
278
279  fail:
280         send_client_data(3, abort_msg, sizeof(abort_msg));
281         die("git upload-pack: %s", abort_msg);
282 }
283
284 static int got_oid(const char *hex, struct object_id *oid)
285 {
286         struct object *o;
287         int we_knew_they_have = 0;
288
289         if (get_oid_hex(hex, oid))
290                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
291         if (!has_object_file(oid))
292                 return -1;
293
294         o = parse_object(oid);
295         if (!o)
296                 die("oops (%s)", oid_to_hex(oid));
297         if (o->type == OBJ_COMMIT) {
298                 struct commit_list *parents;
299                 struct commit *commit = (struct commit *)o;
300                 if (o->flags & THEY_HAVE)
301                         we_knew_they_have = 1;
302                 else
303                         o->flags |= THEY_HAVE;
304                 if (!oldest_have || (commit->date < oldest_have))
305                         oldest_have = commit->date;
306                 for (parents = commit->parents;
307                      parents;
308                      parents = parents->next)
309                         parents->item->object.flags |= THEY_HAVE;
310         }
311         if (!we_knew_they_have) {
312                 add_object_array(o, NULL, &have_obj);
313                 return 1;
314         }
315         return 0;
316 }
317
318 static int reachable(struct commit *want)
319 {
320         struct prio_queue work = { compare_commits_by_commit_date };
321
322         prio_queue_put(&work, want);
323         while (work.nr) {
324                 struct commit_list *list;
325                 struct commit *commit = prio_queue_get(&work);
326
327                 if (commit->object.flags & THEY_HAVE) {
328                         want->object.flags |= COMMON_KNOWN;
329                         break;
330                 }
331                 if (!commit->object.parsed)
332                         parse_object(&commit->object.oid);
333                 if (commit->object.flags & REACHABLE)
334                         continue;
335                 commit->object.flags |= REACHABLE;
336                 if (commit->date < oldest_have)
337                         continue;
338                 for (list = commit->parents; list; list = list->next) {
339                         struct commit *parent = list->item;
340                         if (!(parent->object.flags & REACHABLE))
341                                 prio_queue_put(&work, parent);
342                 }
343         }
344         want->object.flags |= REACHABLE;
345         clear_commit_marks(want, REACHABLE);
346         clear_prio_queue(&work);
347         return (want->object.flags & COMMON_KNOWN);
348 }
349
350 static int ok_to_give_up(void)
351 {
352         int i;
353
354         if (!have_obj.nr)
355                 return 0;
356
357         for (i = 0; i < want_obj.nr; i++) {
358                 struct object *want = want_obj.objects[i].item;
359
360                 if (want->flags & COMMON_KNOWN)
361                         continue;
362                 want = deref_tag(want, "a want line", 0);
363                 if (!want || want->type != OBJ_COMMIT) {
364                         /* no way to tell if this is reachable by
365                          * looking at the ancestry chain alone, so
366                          * leave a note to ourselves not to worry about
367                          * this object anymore.
368                          */
369                         want_obj.objects[i].item->flags |= COMMON_KNOWN;
370                         continue;
371                 }
372                 if (!reachable((struct commit *)want))
373                         return 0;
374         }
375         return 1;
376 }
377
378 static int get_common_commits(void)
379 {
380         struct object_id oid;
381         char last_hex[GIT_MAX_HEXSZ + 1];
382         int got_common = 0;
383         int got_other = 0;
384         int sent_ready = 0;
385
386         save_commit_buffer = 0;
387
388         for (;;) {
389                 char *line = packet_read_line(0, NULL);
390                 const char *arg;
391
392                 reset_timeout();
393
394                 if (!line) {
395                         if (multi_ack == 2 && got_common
396                             && !got_other && ok_to_give_up()) {
397                                 sent_ready = 1;
398                                 packet_write_fmt(1, "ACK %s ready\n", last_hex);
399                         }
400                         if (have_obj.nr == 0 || multi_ack)
401                                 packet_write_fmt(1, "NAK\n");
402
403                         if (no_done && sent_ready) {
404                                 packet_write_fmt(1, "ACK %s\n", last_hex);
405                                 return 0;
406                         }
407                         if (stateless_rpc)
408                                 exit(0);
409                         got_common = 0;
410                         got_other = 0;
411                         continue;
412                 }
413                 if (skip_prefix(line, "have ", &arg)) {
414                         switch (got_oid(arg, &oid)) {
415                         case -1: /* they have what we do not */
416                                 got_other = 1;
417                                 if (multi_ack && ok_to_give_up()) {
418                                         const char *hex = oid_to_hex(&oid);
419                                         if (multi_ack == 2) {
420                                                 sent_ready = 1;
421                                                 packet_write_fmt(1, "ACK %s ready\n", hex);
422                                         } else
423                                                 packet_write_fmt(1, "ACK %s continue\n", hex);
424                                 }
425                                 break;
426                         default:
427                                 got_common = 1;
428                                 memcpy(last_hex, oid_to_hex(&oid), 41);
429                                 if (multi_ack == 2)
430                                         packet_write_fmt(1, "ACK %s common\n", last_hex);
431                                 else if (multi_ack)
432                                         packet_write_fmt(1, "ACK %s continue\n", last_hex);
433                                 else if (have_obj.nr == 1)
434                                         packet_write_fmt(1, "ACK %s\n", last_hex);
435                                 break;
436                         }
437                         continue;
438                 }
439                 if (!strcmp(line, "done")) {
440                         if (have_obj.nr > 0) {
441                                 if (multi_ack)
442                                         packet_write_fmt(1, "ACK %s\n", last_hex);
443                                 return 0;
444                         }
445                         packet_write_fmt(1, "NAK\n");
446                         return -1;
447                 }
448                 die("git upload-pack: expected SHA1 list, got '%s'", line);
449         }
450 }
451
452 static int is_our_ref(struct object *o)
453 {
454         int allow_hidden_ref = (allow_unadvertised_object_request &
455                         (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1));
456         return o->flags & ((allow_hidden_ref ? HIDDEN_REF : 0) | OUR_REF);
457 }
458
459 /*
460  * on successful case, it's up to the caller to close cmd->out
461  */
462 static int do_reachable_revlist(struct child_process *cmd,
463                                 struct object_array *src,
464                                 struct object_array *reachable)
465 {
466         static const char *argv[] = {
467                 "rev-list", "--stdin", NULL,
468         };
469         struct object *o;
470         char namebuf[42]; /* ^ + SHA-1 + LF */
471         int i;
472
473         cmd->argv = argv;
474         cmd->git_cmd = 1;
475         cmd->no_stderr = 1;
476         cmd->in = -1;
477         cmd->out = -1;
478
479         /*
480          * If the next rev-list --stdin encounters an unknown commit,
481          * it terminates, which will cause SIGPIPE in the write loop
482          * below.
483          */
484         sigchain_push(SIGPIPE, SIG_IGN);
485
486         if (start_command(cmd))
487                 goto error;
488
489         namebuf[0] = '^';
490         namebuf[GIT_SHA1_HEXSZ + 1] = '\n';
491         for (i = get_max_object_index(); 0 < i; ) {
492                 o = get_indexed_object(--i);
493                 if (!o)
494                         continue;
495                 if (reachable && o->type == OBJ_COMMIT)
496                         o->flags &= ~TMP_MARK;
497                 if (!is_our_ref(o))
498                         continue;
499                 memcpy(namebuf + 1, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
500                 if (write_in_full(cmd->in, namebuf, GIT_SHA1_HEXSZ + 2) < 0)
501                         goto error;
502         }
503         namebuf[GIT_SHA1_HEXSZ] = '\n';
504         for (i = 0; i < src->nr; i++) {
505                 o = src->objects[i].item;
506                 if (is_our_ref(o)) {
507                         if (reachable)
508                                 add_object_array(o, NULL, reachable);
509                         continue;
510                 }
511                 if (reachable && o->type == OBJ_COMMIT)
512                         o->flags |= TMP_MARK;
513                 memcpy(namebuf, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
514                 if (write_in_full(cmd->in, namebuf, GIT_SHA1_HEXSZ + 1) < 0)
515                         goto error;
516         }
517         close(cmd->in);
518         cmd->in = -1;
519         sigchain_pop(SIGPIPE);
520
521         return 0;
522
523 error:
524         sigchain_pop(SIGPIPE);
525
526         if (cmd->in >= 0)
527                 close(cmd->in);
528         if (cmd->out >= 0)
529                 close(cmd->out);
530         return -1;
531 }
532
533 static int get_reachable_list(struct object_array *src,
534                               struct object_array *reachable)
535 {
536         struct child_process cmd = CHILD_PROCESS_INIT;
537         int i;
538         struct object *o;
539         char namebuf[42]; /* ^ + SHA-1 + LF */
540
541         if (do_reachable_revlist(&cmd, src, reachable) < 0)
542                 return -1;
543
544         while ((i = read_in_full(cmd.out, namebuf, 41)) == 41) {
545                 struct object_id sha1;
546
547                 if (namebuf[40] != '\n' || get_oid_hex(namebuf, &sha1))
548                         break;
549
550                 o = lookup_object(sha1.hash);
551                 if (o && o->type == OBJ_COMMIT) {
552                         o->flags &= ~TMP_MARK;
553                 }
554         }
555         for (i = get_max_object_index(); 0 < i; i--) {
556                 o = get_indexed_object(i - 1);
557                 if (o && o->type == OBJ_COMMIT &&
558                     (o->flags & TMP_MARK)) {
559                         add_object_array(o, NULL, reachable);
560                                 o->flags &= ~TMP_MARK;
561                 }
562         }
563         close(cmd.out);
564
565         if (finish_command(&cmd))
566                 return -1;
567
568         return 0;
569 }
570
571 static int has_unreachable(struct object_array *src)
572 {
573         struct child_process cmd = CHILD_PROCESS_INIT;
574         char buf[1];
575         int i;
576
577         if (do_reachable_revlist(&cmd, src, NULL) < 0)
578                 return 1;
579
580         /*
581          * The commits out of the rev-list are not ancestors of
582          * our ref.
583          */
584         i = read_in_full(cmd.out, buf, 1);
585         if (i)
586                 goto error;
587         close(cmd.out);
588         cmd.out = -1;
589
590         /*
591          * rev-list may have died by encountering a bad commit
592          * in the history, in which case we do want to bail out
593          * even when it showed no commit.
594          */
595         if (finish_command(&cmd))
596                 goto error;
597
598         /* All the non-tip ones are ancestors of what we advertised */
599         return 0;
600
601 error:
602         sigchain_pop(SIGPIPE);
603         if (cmd.out >= 0)
604                 close(cmd.out);
605         return 1;
606 }
607
608 static void check_non_tip(void)
609 {
610         int i;
611
612         /*
613          * In the normal in-process case without
614          * uploadpack.allowReachableSHA1InWant,
615          * non-tip requests can never happen.
616          */
617         if (!stateless_rpc && !(allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1))
618                 goto error;
619         if (!has_unreachable(&want_obj))
620                 /* All the non-tip ones are ancestors of what we advertised */
621                 return;
622
623 error:
624         /* Pick one of them (we know there at least is one) */
625         for (i = 0; i < want_obj.nr; i++) {
626                 struct object *o = want_obj.objects[i].item;
627                 if (!is_our_ref(o))
628                         die("git upload-pack: not our ref %s",
629                             oid_to_hex(&o->oid));
630         }
631 }
632
633 static void send_shallow(struct commit_list *result)
634 {
635         while (result) {
636                 struct object *object = &result->item->object;
637                 if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
638                         packet_write_fmt(1, "shallow %s",
639                                          oid_to_hex(&object->oid));
640                         register_shallow(&object->oid);
641                         shallow_nr++;
642                 }
643                 result = result->next;
644         }
645 }
646
647 static void send_unshallow(const struct object_array *shallows)
648 {
649         int i;
650
651         for (i = 0; i < shallows->nr; i++) {
652                 struct object *object = shallows->objects[i].item;
653                 if (object->flags & NOT_SHALLOW) {
654                         struct commit_list *parents;
655                         packet_write_fmt(1, "unshallow %s",
656                                          oid_to_hex(&object->oid));
657                         object->flags &= ~CLIENT_SHALLOW;
658                         /*
659                          * We want to _register_ "object" as shallow, but we
660                          * also need to traverse object's parents to deepen a
661                          * shallow clone. Unregister it for now so we can
662                          * parse and add the parents to the want list, then
663                          * re-register it.
664                          */
665                         unregister_shallow(&object->oid);
666                         object->parsed = 0;
667                         parse_commit_or_die((struct commit *)object);
668                         parents = ((struct commit *)object)->parents;
669                         while (parents) {
670                                 add_object_array(&parents->item->object,
671                                                  NULL, &want_obj);
672                                 parents = parents->next;
673                         }
674                         add_object_array(object, NULL, &extra_edge_obj);
675                 }
676                 /* make sure commit traversal conforms to client */
677                 register_shallow(&object->oid);
678         }
679 }
680
681 static void deepen(int depth, int deepen_relative,
682                    struct object_array *shallows)
683 {
684         if (depth == INFINITE_DEPTH && !is_repository_shallow()) {
685                 int i;
686
687                 for (i = 0; i < shallows->nr; i++) {
688                         struct object *object = shallows->objects[i].item;
689                         object->flags |= NOT_SHALLOW;
690                 }
691         } else if (deepen_relative) {
692                 struct object_array reachable_shallows = OBJECT_ARRAY_INIT;
693                 struct commit_list *result;
694
695                 get_reachable_list(shallows, &reachable_shallows);
696                 result = get_shallow_commits(&reachable_shallows,
697                                              depth + 1,
698                                              SHALLOW, NOT_SHALLOW);
699                 send_shallow(result);
700                 free_commit_list(result);
701                 object_array_clear(&reachable_shallows);
702         } else {
703                 struct commit_list *result;
704
705                 result = get_shallow_commits(&want_obj, depth,
706                                              SHALLOW, NOT_SHALLOW);
707                 send_shallow(result);
708                 free_commit_list(result);
709         }
710
711         send_unshallow(shallows);
712         packet_flush(1);
713 }
714
715 static void deepen_by_rev_list(int ac, const char **av,
716                                struct object_array *shallows)
717 {
718         struct commit_list *result;
719
720         result = get_shallow_commits_by_rev_list(ac, av, SHALLOW, NOT_SHALLOW);
721         send_shallow(result);
722         free_commit_list(result);
723         send_unshallow(shallows);
724         packet_flush(1);
725 }
726
727 static int process_shallow(const char *line, struct object_array *shallows)
728 {
729         const char *arg;
730         if (skip_prefix(line, "shallow ", &arg)) {
731                 struct object_id oid;
732                 struct object *object;
733                 if (get_oid_hex(arg, &oid))
734                         die("invalid shallow line: %s", line);
735                 object = parse_object(&oid);
736                 if (!object)
737                         return 1;
738                 if (object->type != OBJ_COMMIT)
739                         die("invalid shallow object %s", oid_to_hex(&oid));
740                 if (!(object->flags & CLIENT_SHALLOW)) {
741                         object->flags |= CLIENT_SHALLOW;
742                         add_object_array(object, NULL, shallows);
743                 }
744                 return 1;
745         }
746
747         return 0;
748 }
749
750 static int process_deepen(const char *line, int *depth)
751 {
752         const char *arg;
753         if (skip_prefix(line, "deepen ", &arg)) {
754                 char *end = NULL;
755                 *depth = (int)strtol(arg, &end, 0);
756                 if (!end || *end || *depth <= 0)
757                         die("Invalid deepen: %s", line);
758                 return 1;
759         }
760
761         return 0;
762 }
763
764 static int process_deepen_since(const char *line, timestamp_t *deepen_since, int *deepen_rev_list)
765 {
766         const char *arg;
767         if (skip_prefix(line, "deepen-since ", &arg)) {
768                 char *end = NULL;
769                 *deepen_since = parse_timestamp(arg, &end, 0);
770                 if (!end || *end || !deepen_since ||
771                     /* revisions.c's max_age -1 is special */
772                     *deepen_since == -1)
773                         die("Invalid deepen-since: %s", line);
774                 *deepen_rev_list = 1;
775                 return 1;
776         }
777         return 0;
778 }
779
780 static int process_deepen_not(const char *line, struct string_list *deepen_not, int *deepen_rev_list)
781 {
782         const char *arg;
783         if (skip_prefix(line, "deepen-not ", &arg)) {
784                 char *ref = NULL;
785                 struct object_id oid;
786                 if (expand_ref(arg, strlen(arg), &oid, &ref) != 1)
787                         die("git upload-pack: ambiguous deepen-not: %s", line);
788                 string_list_append(deepen_not, ref);
789                 free(ref);
790                 *deepen_rev_list = 1;
791                 return 1;
792         }
793         return 0;
794 }
795
796 static void receive_needs(void)
797 {
798         struct object_array shallows = OBJECT_ARRAY_INIT;
799         struct string_list deepen_not = STRING_LIST_INIT_DUP;
800         int depth = 0;
801         int has_non_tip = 0;
802         timestamp_t deepen_since = 0;
803         int deepen_rev_list = 0;
804
805         shallow_nr = 0;
806         for (;;) {
807                 struct object *o;
808                 const char *features;
809                 struct object_id oid_buf;
810                 char *line = packet_read_line(0, NULL);
811                 const char *arg;
812
813                 reset_timeout();
814                 if (!line)
815                         break;
816
817                 if (process_shallow(line, &shallows))
818                         continue;
819                 if (process_deepen(line, &depth))
820                         continue;
821                 if (process_deepen_since(line, &deepen_since, &deepen_rev_list))
822                         continue;
823                 if (process_deepen_not(line, &deepen_not, &deepen_rev_list))
824                         continue;
825
826                 if (!skip_prefix(line, "want ", &arg) ||
827                     get_oid_hex(arg, &oid_buf))
828                         die("git upload-pack: protocol error, "
829                             "expected to get sha, not '%s'", line);
830
831                 features = arg + 40;
832
833                 if (parse_feature_request(features, "deepen-relative"))
834                         deepen_relative = 1;
835                 if (parse_feature_request(features, "multi_ack_detailed"))
836                         multi_ack = 2;
837                 else if (parse_feature_request(features, "multi_ack"))
838                         multi_ack = 1;
839                 if (parse_feature_request(features, "no-done"))
840                         no_done = 1;
841                 if (parse_feature_request(features, "thin-pack"))
842                         use_thin_pack = 1;
843                 if (parse_feature_request(features, "ofs-delta"))
844                         use_ofs_delta = 1;
845                 if (parse_feature_request(features, "side-band-64k"))
846                         use_sideband = LARGE_PACKET_MAX;
847                 else if (parse_feature_request(features, "side-band"))
848                         use_sideband = DEFAULT_PACKET_MAX;
849                 if (parse_feature_request(features, "no-progress"))
850                         no_progress = 1;
851                 if (parse_feature_request(features, "include-tag"))
852                         use_include_tag = 1;
853
854                 o = parse_object(&oid_buf);
855                 if (!o) {
856                         packet_write_fmt(1,
857                                          "ERR upload-pack: not our ref %s",
858                                          oid_to_hex(&oid_buf));
859                         die("git upload-pack: not our ref %s",
860                             oid_to_hex(&oid_buf));
861                 }
862                 if (!(o->flags & WANTED)) {
863                         o->flags |= WANTED;
864                         if (!((allow_unadvertised_object_request & ALLOW_ANY_SHA1) == ALLOW_ANY_SHA1
865                               || is_our_ref(o)))
866                                 has_non_tip = 1;
867                         add_object_array(o, NULL, &want_obj);
868                 }
869         }
870
871         /*
872          * We have sent all our refs already, and the other end
873          * should have chosen out of them. When we are operating
874          * in the stateless RPC mode, however, their choice may
875          * have been based on the set of older refs advertised
876          * by another process that handled the initial request.
877          */
878         if (has_non_tip)
879                 check_non_tip();
880
881         if (!use_sideband && daemon_mode)
882                 no_progress = 1;
883
884         if (depth == 0 && !deepen_rev_list && shallows.nr == 0)
885                 return;
886         if (depth > 0 && deepen_rev_list)
887                 die("git upload-pack: deepen and deepen-since (or deepen-not) cannot be used together");
888         if (depth > 0)
889                 deepen(depth, deepen_relative, &shallows);
890         else if (deepen_rev_list) {
891                 struct argv_array av = ARGV_ARRAY_INIT;
892                 int i;
893
894                 argv_array_push(&av, "rev-list");
895                 if (deepen_since)
896                         argv_array_pushf(&av, "--max-age=%"PRItime, deepen_since);
897                 if (deepen_not.nr) {
898                         argv_array_push(&av, "--not");
899                         for (i = 0; i < deepen_not.nr; i++) {
900                                 struct string_list_item *s = deepen_not.items + i;
901                                 argv_array_push(&av, s->string);
902                         }
903                         argv_array_push(&av, "--not");
904                 }
905                 for (i = 0; i < want_obj.nr; i++) {
906                         struct object *o = want_obj.objects[i].item;
907                         argv_array_push(&av, oid_to_hex(&o->oid));
908                 }
909                 deepen_by_rev_list(av.argc, av.argv, &shallows);
910                 argv_array_clear(&av);
911         }
912         else
913                 if (shallows.nr > 0) {
914                         int i;
915                         for (i = 0; i < shallows.nr; i++)
916                                 register_shallow(&shallows.objects[i].item->oid);
917                 }
918
919         shallow_nr += shallows.nr;
920         object_array_clear(&shallows);
921 }
922
923 /* return non-zero if the ref is hidden, otherwise 0 */
924 static int mark_our_ref(const char *refname, const char *refname_full,
925                         const struct object_id *oid)
926 {
927         struct object *o = lookup_unknown_object(oid->hash);
928
929         if (ref_is_hidden(refname, refname_full)) {
930                 o->flags |= HIDDEN_REF;
931                 return 1;
932         }
933         o->flags |= OUR_REF;
934         return 0;
935 }
936
937 static int check_ref(const char *refname_full, const struct object_id *oid,
938                      int flag, void *cb_data)
939 {
940         const char *refname = strip_namespace(refname_full);
941
942         mark_our_ref(refname, refname_full, oid);
943         return 0;
944 }
945
946 static void format_symref_info(struct strbuf *buf, struct string_list *symref)
947 {
948         struct string_list_item *item;
949
950         if (!symref->nr)
951                 return;
952         for_each_string_list_item(item, symref)
953                 strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util);
954 }
955
956 static int send_ref(const char *refname, const struct object_id *oid,
957                     int flag, void *cb_data)
958 {
959         static const char *capabilities = "multi_ack thin-pack side-band"
960                 " side-band-64k ofs-delta shallow deepen-since deepen-not"
961                 " deepen-relative no-progress include-tag multi_ack_detailed";
962         const char *refname_nons = strip_namespace(refname);
963         struct object_id peeled;
964
965         if (mark_our_ref(refname_nons, refname, oid))
966                 return 0;
967
968         if (capabilities) {
969                 struct strbuf symref_info = STRBUF_INIT;
970
971                 format_symref_info(&symref_info, cb_data);
972                 packet_write_fmt(1, "%s %s%c%s%s%s%s%s agent=%s\n",
973                              oid_to_hex(oid), refname_nons,
974                              0, capabilities,
975                              (allow_unadvertised_object_request & ALLOW_TIP_SHA1) ?
976                                      " allow-tip-sha1-in-want" : "",
977                              (allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1) ?
978                                      " allow-reachable-sha1-in-want" : "",
979                              stateless_rpc ? " no-done" : "",
980                              symref_info.buf,
981                              git_user_agent_sanitized());
982                 strbuf_release(&symref_info);
983         } else {
984                 packet_write_fmt(1, "%s %s\n", oid_to_hex(oid), refname_nons);
985         }
986         capabilities = NULL;
987         if (!peel_ref(refname, &peeled))
988                 packet_write_fmt(1, "%s %s^{}\n", oid_to_hex(&peeled), refname_nons);
989         return 0;
990 }
991
992 static int find_symref(const char *refname, const struct object_id *oid,
993                        int flag, void *cb_data)
994 {
995         const char *symref_target;
996         struct string_list_item *item;
997
998         if ((flag & REF_ISSYMREF) == 0)
999                 return 0;
1000         symref_target = resolve_ref_unsafe(refname, 0, NULL, &flag);
1001         if (!symref_target || (flag & REF_ISSYMREF) == 0)
1002                 die("'%s' is a symref but it is not?", refname);
1003         item = string_list_append(cb_data, refname);
1004         item->util = xstrdup(symref_target);
1005         return 0;
1006 }
1007
1008 static int upload_pack_config(const char *var, const char *value, void *unused)
1009 {
1010         if (!strcmp("uploadpack.allowtipsha1inwant", var)) {
1011                 if (git_config_bool(var, value))
1012                         allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
1013                 else
1014                         allow_unadvertised_object_request &= ~ALLOW_TIP_SHA1;
1015         } else if (!strcmp("uploadpack.allowreachablesha1inwant", var)) {
1016                 if (git_config_bool(var, value))
1017                         allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1018                 else
1019                         allow_unadvertised_object_request &= ~ALLOW_REACHABLE_SHA1;
1020         } else if (!strcmp("uploadpack.allowanysha1inwant", var)) {
1021                 if (git_config_bool(var, value))
1022                         allow_unadvertised_object_request |= ALLOW_ANY_SHA1;
1023                 else
1024                         allow_unadvertised_object_request &= ~ALLOW_ANY_SHA1;
1025         } else if (!strcmp("uploadpack.keepalive", var)) {
1026                 keepalive = git_config_int(var, value);
1027                 if (!keepalive)
1028                         keepalive = -1;
1029         } else if (current_config_scope() != CONFIG_SCOPE_REPO) {
1030                 if (!strcmp("uploadpack.packobjectshook", var))
1031                         return git_config_string(&pack_objects_hook, var, value);
1032         }
1033         return parse_hide_refs_config(var, value, "uploadpack");
1034 }
1035
1036 void upload_pack(struct upload_pack_options *options)
1037 {
1038         struct string_list symref = STRING_LIST_INIT_DUP;
1039
1040         stateless_rpc = options->stateless_rpc;
1041         timeout = options->timeout;
1042         daemon_mode = options->daemon_mode;
1043
1044         git_config(upload_pack_config, NULL);
1045
1046         head_ref_namespaced(find_symref, &symref);
1047
1048         if (options->advertise_refs || !stateless_rpc) {
1049                 reset_timeout();
1050                 head_ref_namespaced(send_ref, &symref);
1051                 for_each_namespaced_ref(send_ref, &symref);
1052                 advertise_shallow_grafts(1);
1053                 packet_flush(1);
1054         } else {
1055                 head_ref_namespaced(check_ref, NULL);
1056                 for_each_namespaced_ref(check_ref, NULL);
1057         }
1058         string_list_clear(&symref, 1);
1059         if (options->advertise_refs)
1060                 return;
1061
1062         receive_needs();
1063         if (want_obj.nr) {
1064                 get_common_commits();
1065                 create_pack_file();
1066         }
1067 }