config_set_store: rename some fields for consistency
[git] / fetch-pack.c
1 #include "cache.h"
2 #include "config.h"
3 #include "lockfile.h"
4 #include "refs.h"
5 #include "pkt-line.h"
6 #include "commit.h"
7 #include "tag.h"
8 #include "exec_cmd.h"
9 #include "pack.h"
10 #include "sideband.h"
11 #include "fetch-pack.h"
12 #include "remote.h"
13 #include "run-command.h"
14 #include "connect.h"
15 #include "transport.h"
16 #include "version.h"
17 #include "prio-queue.h"
18 #include "sha1-array.h"
19 #include "oidset.h"
20 #include "packfile.h"
21
22 static int transfer_unpack_limit = -1;
23 static int fetch_unpack_limit = -1;
24 static int unpack_limit = 100;
25 static int prefer_ofs_delta = 1;
26 static int no_done;
27 static int deepen_since_ok;
28 static int deepen_not_ok;
29 static int fetch_fsck_objects = -1;
30 static int transfer_fsck_objects = -1;
31 static int agent_supported;
32 static struct lock_file shallow_lock;
33 static const char *alternate_shallow_file;
34
35 /* Remember to update object flag allocation in object.h */
36 #define COMPLETE        (1U << 0)
37 #define COMMON          (1U << 1)
38 #define COMMON_REF      (1U << 2)
39 #define SEEN            (1U << 3)
40 #define POPPED          (1U << 4)
41 #define ALTERNATE       (1U << 5)
42
43 static int marked;
44
45 /*
46  * After sending this many "have"s if we do not get any new ACK , we
47  * give up traversing our history.
48  */
49 #define MAX_IN_VAIN 256
50
51 static struct prio_queue rev_list = { compare_commits_by_commit_date };
52 static int non_common_revs, multi_ack, use_sideband;
53 /* Allow specifying sha1 if it is a ref tip. */
54 #define ALLOW_TIP_SHA1  01
55 /* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
56 #define ALLOW_REACHABLE_SHA1    02
57 static unsigned int allow_unadvertised_object_request;
58
59 __attribute__((format (printf, 2, 3)))
60 static inline void print_verbose(const struct fetch_pack_args *args,
61                                  const char *fmt, ...)
62 {
63         va_list params;
64
65         if (!args->verbose)
66                 return;
67
68         va_start(params, fmt);
69         vfprintf(stderr, fmt, params);
70         va_end(params);
71         fputc('\n', stderr);
72 }
73
74 struct alternate_object_cache {
75         struct object **items;
76         size_t nr, alloc;
77 };
78
79 static void cache_one_alternate(const char *refname,
80                                 const struct object_id *oid,
81                                 void *vcache)
82 {
83         struct alternate_object_cache *cache = vcache;
84         struct object *obj = parse_object(oid);
85
86         if (!obj || (obj->flags & ALTERNATE))
87                 return;
88
89         obj->flags |= ALTERNATE;
90         ALLOC_GROW(cache->items, cache->nr + 1, cache->alloc);
91         cache->items[cache->nr++] = obj;
92 }
93
94 static void for_each_cached_alternate(void (*cb)(struct object *))
95 {
96         static int initialized;
97         static struct alternate_object_cache cache;
98         size_t i;
99
100         if (!initialized) {
101                 for_each_alternate_ref(cache_one_alternate, &cache);
102                 initialized = 1;
103         }
104
105         for (i = 0; i < cache.nr; i++)
106                 cb(cache.items[i]);
107 }
108
109 static void rev_list_push(struct commit *commit, int mark)
110 {
111         if (!(commit->object.flags & mark)) {
112                 commit->object.flags |= mark;
113
114                 if (parse_commit(commit))
115                         return;
116
117                 prio_queue_put(&rev_list, commit);
118
119                 if (!(commit->object.flags & COMMON))
120                         non_common_revs++;
121         }
122 }
123
124 static int rev_list_insert_ref(const char *refname, const struct object_id *oid)
125 {
126         struct object *o = deref_tag(parse_object(oid), refname, 0);
127
128         if (o && o->type == OBJ_COMMIT)
129                 rev_list_push((struct commit *)o, SEEN);
130
131         return 0;
132 }
133
134 static int rev_list_insert_ref_oid(const char *refname, const struct object_id *oid,
135                                    int flag, void *cb_data)
136 {
137         return rev_list_insert_ref(refname, oid);
138 }
139
140 static int clear_marks(const char *refname, const struct object_id *oid,
141                        int flag, void *cb_data)
142 {
143         struct object *o = deref_tag(parse_object(oid), refname, 0);
144
145         if (o && o->type == OBJ_COMMIT)
146                 clear_commit_marks((struct commit *)o,
147                                    COMMON | COMMON_REF | SEEN | POPPED);
148         return 0;
149 }
150
151 /*
152    This function marks a rev and its ancestors as common.
153    In some cases, it is desirable to mark only the ancestors (for example
154    when only the server does not yet know that they are common).
155 */
156
157 static void mark_common(struct commit *commit,
158                 int ancestors_only, int dont_parse)
159 {
160         if (commit != NULL && !(commit->object.flags & COMMON)) {
161                 struct object *o = (struct object *)commit;
162
163                 if (!ancestors_only)
164                         o->flags |= COMMON;
165
166                 if (!(o->flags & SEEN))
167                         rev_list_push(commit, SEEN);
168                 else {
169                         struct commit_list *parents;
170
171                         if (!ancestors_only && !(o->flags & POPPED))
172                                 non_common_revs--;
173                         if (!o->parsed && !dont_parse)
174                                 if (parse_commit(commit))
175                                         return;
176
177                         for (parents = commit->parents;
178                                         parents;
179                                         parents = parents->next)
180                                 mark_common(parents->item, 0, dont_parse);
181                 }
182         }
183 }
184
185 /*
186   Get the next rev to send, ignoring the common.
187 */
188
189 static const struct object_id *get_rev(void)
190 {
191         struct commit *commit = NULL;
192
193         while (commit == NULL) {
194                 unsigned int mark;
195                 struct commit_list *parents;
196
197                 if (rev_list.nr == 0 || non_common_revs == 0)
198                         return NULL;
199
200                 commit = prio_queue_get(&rev_list);
201                 parse_commit(commit);
202                 parents = commit->parents;
203
204                 commit->object.flags |= POPPED;
205                 if (!(commit->object.flags & COMMON))
206                         non_common_revs--;
207
208                 if (commit->object.flags & COMMON) {
209                         /* do not send "have", and ignore ancestors */
210                         commit = NULL;
211                         mark = COMMON | SEEN;
212                 } else if (commit->object.flags & COMMON_REF)
213                         /* send "have", and ignore ancestors */
214                         mark = COMMON | SEEN;
215                 else
216                         /* send "have", also for its ancestors */
217                         mark = SEEN;
218
219                 while (parents) {
220                         if (!(parents->item->object.flags & SEEN))
221                                 rev_list_push(parents->item, mark);
222                         if (mark & COMMON)
223                                 mark_common(parents->item, 1, 0);
224                         parents = parents->next;
225                 }
226         }
227
228         return &commit->object.oid;
229 }
230
231 enum ack_type {
232         NAK = 0,
233         ACK,
234         ACK_continue,
235         ACK_common,
236         ACK_ready
237 };
238
239 static void consume_shallow_list(struct fetch_pack_args *args, int fd)
240 {
241         if (args->stateless_rpc && args->deepen) {
242                 /* If we sent a depth we will get back "duplicate"
243                  * shallow and unshallow commands every time there
244                  * is a block of have lines exchanged.
245                  */
246                 char *line;
247                 while ((line = packet_read_line(fd, NULL))) {
248                         if (starts_with(line, "shallow "))
249                                 continue;
250                         if (starts_with(line, "unshallow "))
251                                 continue;
252                         die(_("git fetch-pack: expected shallow list"));
253                 }
254         }
255 }
256
257 static enum ack_type get_ack(int fd, struct object_id *result_oid)
258 {
259         int len;
260         char *line = packet_read_line(fd, &len);
261         const char *arg;
262
263         if (!len)
264                 die(_("git fetch-pack: expected ACK/NAK, got EOF"));
265         if (!strcmp(line, "NAK"))
266                 return NAK;
267         if (skip_prefix(line, "ACK ", &arg)) {
268                 if (!get_oid_hex(arg, result_oid)) {
269                         arg += 40;
270                         len -= arg - line;
271                         if (len < 1)
272                                 return ACK;
273                         if (strstr(arg, "continue"))
274                                 return ACK_continue;
275                         if (strstr(arg, "common"))
276                                 return ACK_common;
277                         if (strstr(arg, "ready"))
278                                 return ACK_ready;
279                         return ACK;
280                 }
281         }
282         if (skip_prefix(line, "ERR ", &arg))
283                 die(_("remote error: %s"), arg);
284         die(_("git fetch-pack: expected ACK/NAK, got '%s'"), line);
285 }
286
287 static void send_request(struct fetch_pack_args *args,
288                          int fd, struct strbuf *buf)
289 {
290         if (args->stateless_rpc) {
291                 send_sideband(fd, -1, buf->buf, buf->len, LARGE_PACKET_MAX);
292                 packet_flush(fd);
293         } else
294                 write_or_die(fd, buf->buf, buf->len);
295 }
296
297 static void insert_one_alternate_object(struct object *obj)
298 {
299         rev_list_insert_ref(NULL, &obj->oid);
300 }
301
302 #define INITIAL_FLUSH 16
303 #define PIPESAFE_FLUSH 32
304 #define LARGE_FLUSH 16384
305
306 static int next_flush(struct fetch_pack_args *args, int count)
307 {
308         if (args->stateless_rpc) {
309                 if (count < LARGE_FLUSH)
310                         count <<= 1;
311                 else
312                         count = count * 11 / 10;
313         } else {
314                 if (count < PIPESAFE_FLUSH)
315                         count <<= 1;
316                 else
317                         count += PIPESAFE_FLUSH;
318         }
319         return count;
320 }
321
322 static int find_common(struct fetch_pack_args *args,
323                        int fd[2], struct object_id *result_oid,
324                        struct ref *refs)
325 {
326         int fetching;
327         int count = 0, flushes = 0, flush_at = INITIAL_FLUSH, retval;
328         const struct object_id *oid;
329         unsigned in_vain = 0;
330         int got_continue = 0;
331         int got_ready = 0;
332         struct strbuf req_buf = STRBUF_INIT;
333         size_t state_len = 0;
334
335         if (args->stateless_rpc && multi_ack == 1)
336                 die(_("--stateless-rpc requires multi_ack_detailed"));
337         if (marked)
338                 for_each_ref(clear_marks, NULL);
339         marked = 1;
340
341         for_each_ref(rev_list_insert_ref_oid, NULL);
342         for_each_cached_alternate(insert_one_alternate_object);
343
344         fetching = 0;
345         for ( ; refs ; refs = refs->next) {
346                 struct object_id *remote = &refs->old_oid;
347                 const char *remote_hex;
348                 struct object *o;
349
350                 /*
351                  * If that object is complete (i.e. it is an ancestor of a
352                  * local ref), we tell them we have it but do not have to
353                  * tell them about its ancestors, which they already know
354                  * about.
355                  *
356                  * We use lookup_object here because we are only
357                  * interested in the case we *know* the object is
358                  * reachable and we have already scanned it.
359                  */
360                 if (((o = lookup_object(remote->hash)) != NULL) &&
361                                 (o->flags & COMPLETE)) {
362                         continue;
363                 }
364
365                 remote_hex = oid_to_hex(remote);
366                 if (!fetching) {
367                         struct strbuf c = STRBUF_INIT;
368                         if (multi_ack == 2)     strbuf_addstr(&c, " multi_ack_detailed");
369                         if (multi_ack == 1)     strbuf_addstr(&c, " multi_ack");
370                         if (no_done)            strbuf_addstr(&c, " no-done");
371                         if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
372                         if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
373                         if (args->deepen_relative) strbuf_addstr(&c, " deepen-relative");
374                         if (args->use_thin_pack) strbuf_addstr(&c, " thin-pack");
375                         if (args->no_progress)   strbuf_addstr(&c, " no-progress");
376                         if (args->include_tag)   strbuf_addstr(&c, " include-tag");
377                         if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
378                         if (deepen_since_ok)    strbuf_addstr(&c, " deepen-since");
379                         if (deepen_not_ok)      strbuf_addstr(&c, " deepen-not");
380                         if (agent_supported)    strbuf_addf(&c, " agent=%s",
381                                                             git_user_agent_sanitized());
382                         packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
383                         strbuf_release(&c);
384                 } else
385                         packet_buf_write(&req_buf, "want %s\n", remote_hex);
386                 fetching++;
387         }
388
389         if (!fetching) {
390                 strbuf_release(&req_buf);
391                 packet_flush(fd[1]);
392                 return 1;
393         }
394
395         if (is_repository_shallow())
396                 write_shallow_commits(&req_buf, 1, NULL);
397         if (args->depth > 0)
398                 packet_buf_write(&req_buf, "deepen %d", args->depth);
399         if (args->deepen_since) {
400                 timestamp_t max_age = approxidate(args->deepen_since);
401                 packet_buf_write(&req_buf, "deepen-since %"PRItime, max_age);
402         }
403         if (args->deepen_not) {
404                 int i;
405                 for (i = 0; i < args->deepen_not->nr; i++) {
406                         struct string_list_item *s = args->deepen_not->items + i;
407                         packet_buf_write(&req_buf, "deepen-not %s", s->string);
408                 }
409         }
410         packet_buf_flush(&req_buf);
411         state_len = req_buf.len;
412
413         if (args->deepen) {
414                 char *line;
415                 const char *arg;
416                 struct object_id oid;
417
418                 send_request(args, fd[1], &req_buf);
419                 while ((line = packet_read_line(fd[0], NULL))) {
420                         if (skip_prefix(line, "shallow ", &arg)) {
421                                 if (get_oid_hex(arg, &oid))
422                                         die(_("invalid shallow line: %s"), line);
423                                 register_shallow(&oid);
424                                 continue;
425                         }
426                         if (skip_prefix(line, "unshallow ", &arg)) {
427                                 if (get_oid_hex(arg, &oid))
428                                         die(_("invalid unshallow line: %s"), line);
429                                 if (!lookup_object(oid.hash))
430                                         die(_("object not found: %s"), line);
431                                 /* make sure that it is parsed as shallow */
432                                 if (!parse_object(&oid))
433                                         die(_("error in object: %s"), line);
434                                 if (unregister_shallow(&oid))
435                                         die(_("no shallow found: %s"), line);
436                                 continue;
437                         }
438                         die(_("expected shallow/unshallow, got %s"), line);
439                 }
440         } else if (!args->stateless_rpc)
441                 send_request(args, fd[1], &req_buf);
442
443         if (!args->stateless_rpc) {
444                 /* If we aren't using the stateless-rpc interface
445                  * we don't need to retain the headers.
446                  */
447                 strbuf_setlen(&req_buf, 0);
448                 state_len = 0;
449         }
450
451         flushes = 0;
452         retval = -1;
453         while ((oid = get_rev())) {
454                 packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid));
455                 print_verbose(args, "have %s", oid_to_hex(oid));
456                 in_vain++;
457                 if (flush_at <= ++count) {
458                         int ack;
459
460                         packet_buf_flush(&req_buf);
461                         send_request(args, fd[1], &req_buf);
462                         strbuf_setlen(&req_buf, state_len);
463                         flushes++;
464                         flush_at = next_flush(args, count);
465
466                         /*
467                          * We keep one window "ahead" of the other side, and
468                          * will wait for an ACK only on the next one
469                          */
470                         if (!args->stateless_rpc && count == INITIAL_FLUSH)
471                                 continue;
472
473                         consume_shallow_list(args, fd[0]);
474                         do {
475                                 ack = get_ack(fd[0], result_oid);
476                                 if (ack)
477                                         print_verbose(args, _("got %s %d %s"), "ack",
478                                                       ack, oid_to_hex(result_oid));
479                                 switch (ack) {
480                                 case ACK:
481                                         flushes = 0;
482                                         multi_ack = 0;
483                                         retval = 0;
484                                         goto done;
485                                 case ACK_common:
486                                 case ACK_ready:
487                                 case ACK_continue: {
488                                         struct commit *commit =
489                                                 lookup_commit(result_oid);
490                                         if (!commit)
491                                                 die(_("invalid commit %s"), oid_to_hex(result_oid));
492                                         if (args->stateless_rpc
493                                          && ack == ACK_common
494                                          && !(commit->object.flags & COMMON)) {
495                                                 /* We need to replay the have for this object
496                                                  * on the next RPC request so the peer knows
497                                                  * it is in common with us.
498                                                  */
499                                                 const char *hex = oid_to_hex(result_oid);
500                                                 packet_buf_write(&req_buf, "have %s\n", hex);
501                                                 state_len = req_buf.len;
502                                                 /*
503                                                  * Reset in_vain because an ack
504                                                  * for this commit has not been
505                                                  * seen.
506                                                  */
507                                                 in_vain = 0;
508                                         } else if (!args->stateless_rpc
509                                                    || ack != ACK_common)
510                                                 in_vain = 0;
511                                         mark_common(commit, 0, 1);
512                                         retval = 0;
513                                         got_continue = 1;
514                                         if (ack == ACK_ready) {
515                                                 clear_prio_queue(&rev_list);
516                                                 got_ready = 1;
517                                         }
518                                         break;
519                                         }
520                                 }
521                         } while (ack);
522                         flushes--;
523                         if (got_continue && MAX_IN_VAIN < in_vain) {
524                                 print_verbose(args, _("giving up"));
525                                 break; /* give up */
526                         }
527                 }
528         }
529 done:
530         if (!got_ready || !no_done) {
531                 packet_buf_write(&req_buf, "done\n");
532                 send_request(args, fd[1], &req_buf);
533         }
534         print_verbose(args, _("done"));
535         if (retval != 0) {
536                 multi_ack = 0;
537                 flushes++;
538         }
539         strbuf_release(&req_buf);
540
541         if (!got_ready || !no_done)
542                 consume_shallow_list(args, fd[0]);
543         while (flushes || multi_ack) {
544                 int ack = get_ack(fd[0], result_oid);
545                 if (ack) {
546                         print_verbose(args, _("got %s (%d) %s"), "ack",
547                                       ack, oid_to_hex(result_oid));
548                         if (ack == ACK)
549                                 return 0;
550                         multi_ack = 1;
551                         continue;
552                 }
553                 flushes--;
554         }
555         /* it is no error to fetch into a completely empty repo */
556         return count ? retval : 0;
557 }
558
559 static struct commit_list *complete;
560
561 static int mark_complete(const struct object_id *oid)
562 {
563         struct object *o = parse_object(oid);
564
565         while (o && o->type == OBJ_TAG) {
566                 struct tag *t = (struct tag *) o;
567                 if (!t->tagged)
568                         break; /* broken repository */
569                 o->flags |= COMPLETE;
570                 o = parse_object(&t->tagged->oid);
571         }
572         if (o && o->type == OBJ_COMMIT) {
573                 struct commit *commit = (struct commit *)o;
574                 if (!(commit->object.flags & COMPLETE)) {
575                         commit->object.flags |= COMPLETE;
576                         commit_list_insert(commit, &complete);
577                 }
578         }
579         return 0;
580 }
581
582 static int mark_complete_oid(const char *refname, const struct object_id *oid,
583                              int flag, void *cb_data)
584 {
585         return mark_complete(oid);
586 }
587
588 static void mark_recent_complete_commits(struct fetch_pack_args *args,
589                                          timestamp_t cutoff)
590 {
591         while (complete && cutoff <= complete->item->date) {
592                 print_verbose(args, _("Marking %s as complete"),
593                               oid_to_hex(&complete->item->object.oid));
594                 pop_most_recent_commit(&complete, COMPLETE);
595         }
596 }
597
598 static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
599 {
600         for (; refs; refs = refs->next)
601                 oidset_insert(oids, &refs->old_oid);
602 }
603
604 static int tip_oids_contain(struct oidset *tip_oids,
605                             struct ref *unmatched, struct ref *newlist,
606                             const struct object_id *id)
607 {
608         /*
609          * Note that this only looks at the ref lists the first time it's
610          * called. This works out in filter_refs() because even though it may
611          * add to "newlist" between calls, the additions will always be for
612          * oids that are already in the set.
613          */
614         if (!tip_oids->map.map.tablesize) {
615                 add_refs_to_oidset(tip_oids, unmatched);
616                 add_refs_to_oidset(tip_oids, newlist);
617         }
618         return oidset_contains(tip_oids, id);
619 }
620
621 static void filter_refs(struct fetch_pack_args *args,
622                         struct ref **refs,
623                         struct ref **sought, int nr_sought)
624 {
625         struct ref *newlist = NULL;
626         struct ref **newtail = &newlist;
627         struct ref *unmatched = NULL;
628         struct ref *ref, *next;
629         struct oidset tip_oids = OIDSET_INIT;
630         int i;
631
632         i = 0;
633         for (ref = *refs; ref; ref = next) {
634                 int keep = 0;
635                 next = ref->next;
636
637                 if (starts_with(ref->name, "refs/") &&
638                     check_refname_format(ref->name, 0))
639                         ; /* trash */
640                 else {
641                         while (i < nr_sought) {
642                                 int cmp = strcmp(ref->name, sought[i]->name);
643                                 if (cmp < 0)
644                                         break; /* definitely do not have it */
645                                 else if (cmp == 0) {
646                                         keep = 1; /* definitely have it */
647                                         sought[i]->match_status = REF_MATCHED;
648                                 }
649                                 i++;
650                         }
651                 }
652
653                 if (!keep && args->fetch_all &&
654                     (!args->deepen || !starts_with(ref->name, "refs/tags/")))
655                         keep = 1;
656
657                 if (keep) {
658                         *newtail = ref;
659                         ref->next = NULL;
660                         newtail = &ref->next;
661                 } else {
662                         ref->next = unmatched;
663                         unmatched = ref;
664                 }
665         }
666
667         /* Append unmatched requests to the list */
668         for (i = 0; i < nr_sought; i++) {
669                 struct object_id oid;
670                 const char *p;
671
672                 ref = sought[i];
673                 if (ref->match_status != REF_NOT_MATCHED)
674                         continue;
675                 if (parse_oid_hex(ref->name, &oid, &p) ||
676                     *p != '\0' ||
677                     oidcmp(&oid, &ref->old_oid))
678                         continue;
679
680                 if ((allow_unadvertised_object_request &
681                      (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1)) ||
682                     tip_oids_contain(&tip_oids, unmatched, newlist,
683                                      &ref->old_oid)) {
684                         ref->match_status = REF_MATCHED;
685                         *newtail = copy_ref(ref);
686                         newtail = &(*newtail)->next;
687                 } else {
688                         ref->match_status = REF_UNADVERTISED_NOT_ALLOWED;
689                 }
690         }
691
692         oidset_clear(&tip_oids);
693         for (ref = unmatched; ref; ref = next) {
694                 next = ref->next;
695                 free(ref);
696         }
697
698         *refs = newlist;
699 }
700
701 static void mark_alternate_complete(struct object *obj)
702 {
703         mark_complete(&obj->oid);
704 }
705
706 static int everything_local(struct fetch_pack_args *args,
707                             struct ref **refs,
708                             struct ref **sought, int nr_sought)
709 {
710         struct ref *ref;
711         int retval;
712         timestamp_t cutoff = 0;
713
714         save_commit_buffer = 0;
715
716         for (ref = *refs; ref; ref = ref->next) {
717                 struct object *o;
718
719                 if (!has_object_file_with_flags(&ref->old_oid,
720                                                 OBJECT_INFO_QUICK))
721                         continue;
722
723                 o = parse_object(&ref->old_oid);
724                 if (!o)
725                         continue;
726
727                 /* We already have it -- which may mean that we were
728                  * in sync with the other side at some time after
729                  * that (it is OK if we guess wrong here).
730                  */
731                 if (o->type == OBJ_COMMIT) {
732                         struct commit *commit = (struct commit *)o;
733                         if (!cutoff || cutoff < commit->date)
734                                 cutoff = commit->date;
735                 }
736         }
737
738         if (!args->deepen) {
739                 for_each_ref(mark_complete_oid, NULL);
740                 for_each_cached_alternate(mark_alternate_complete);
741                 commit_list_sort_by_date(&complete);
742                 if (cutoff)
743                         mark_recent_complete_commits(args, cutoff);
744         }
745
746         /*
747          * Mark all complete remote refs as common refs.
748          * Don't mark them common yet; the server has to be told so first.
749          */
750         for (ref = *refs; ref; ref = ref->next) {
751                 struct object *o = deref_tag(lookup_object(ref->old_oid.hash),
752                                              NULL, 0);
753
754                 if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
755                         continue;
756
757                 if (!(o->flags & SEEN)) {
758                         rev_list_push((struct commit *)o, COMMON_REF | SEEN);
759
760                         mark_common((struct commit *)o, 1, 1);
761                 }
762         }
763
764         filter_refs(args, refs, sought, nr_sought);
765
766         for (retval = 1, ref = *refs; ref ; ref = ref->next) {
767                 const struct object_id *remote = &ref->old_oid;
768                 struct object *o;
769
770                 o = lookup_object(remote->hash);
771                 if (!o || !(o->flags & COMPLETE)) {
772                         retval = 0;
773                         print_verbose(args, "want %s (%s)", oid_to_hex(remote),
774                                       ref->name);
775                         continue;
776                 }
777                 print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
778                               ref->name);
779         }
780         return retval;
781 }
782
783 static int sideband_demux(int in, int out, void *data)
784 {
785         int *xd = data;
786         int ret;
787
788         ret = recv_sideband("fetch-pack", xd[0], out);
789         close(out);
790         return ret;
791 }
792
793 static int get_pack(struct fetch_pack_args *args,
794                     int xd[2], char **pack_lockfile)
795 {
796         struct async demux;
797         int do_keep = args->keep_pack;
798         const char *cmd_name;
799         struct pack_header header;
800         int pass_header = 0;
801         struct child_process cmd = CHILD_PROCESS_INIT;
802         int ret;
803
804         memset(&demux, 0, sizeof(demux));
805         if (use_sideband) {
806                 /* xd[] is talking with upload-pack; subprocess reads from
807                  * xd[0], spits out band#2 to stderr, and feeds us band#1
808                  * through demux->out.
809                  */
810                 demux.proc = sideband_demux;
811                 demux.data = xd;
812                 demux.out = -1;
813                 demux.isolate_sigpipe = 1;
814                 if (start_async(&demux))
815                         die(_("fetch-pack: unable to fork off sideband demultiplexer"));
816         }
817         else
818                 demux.out = xd[0];
819
820         if (!args->keep_pack && unpack_limit) {
821
822                 if (read_pack_header(demux.out, &header))
823                         die(_("protocol error: bad pack header"));
824                 pass_header = 1;
825                 if (ntohl(header.hdr_entries) < unpack_limit)
826                         do_keep = 0;
827                 else
828                         do_keep = 1;
829         }
830
831         if (alternate_shallow_file) {
832                 argv_array_push(&cmd.args, "--shallow-file");
833                 argv_array_push(&cmd.args, alternate_shallow_file);
834         }
835
836         if (do_keep) {
837                 if (pack_lockfile)
838                         cmd.out = -1;
839                 cmd_name = "index-pack";
840                 argv_array_push(&cmd.args, cmd_name);
841                 argv_array_push(&cmd.args, "--stdin");
842                 if (!args->quiet && !args->no_progress)
843                         argv_array_push(&cmd.args, "-v");
844                 if (args->use_thin_pack)
845                         argv_array_push(&cmd.args, "--fix-thin");
846                 if (args->lock_pack || unpack_limit) {
847                         char hostname[HOST_NAME_MAX + 1];
848                         if (xgethostname(hostname, sizeof(hostname)))
849                                 xsnprintf(hostname, sizeof(hostname), "localhost");
850                         argv_array_pushf(&cmd.args,
851                                         "--keep=fetch-pack %"PRIuMAX " on %s",
852                                         (uintmax_t)getpid(), hostname);
853                 }
854                 if (args->check_self_contained_and_connected)
855                         argv_array_push(&cmd.args, "--check-self-contained-and-connected");
856         }
857         else {
858                 cmd_name = "unpack-objects";
859                 argv_array_push(&cmd.args, cmd_name);
860                 if (args->quiet || args->no_progress)
861                         argv_array_push(&cmd.args, "-q");
862                 args->check_self_contained_and_connected = 0;
863         }
864
865         if (pass_header)
866                 argv_array_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32,
867                                  ntohl(header.hdr_version),
868                                  ntohl(header.hdr_entries));
869         if (fetch_fsck_objects >= 0
870             ? fetch_fsck_objects
871             : transfer_fsck_objects >= 0
872             ? transfer_fsck_objects
873             : 0)
874                 argv_array_push(&cmd.args, "--strict");
875
876         cmd.in = demux.out;
877         cmd.git_cmd = 1;
878         if (start_command(&cmd))
879                 die(_("fetch-pack: unable to fork off %s"), cmd_name);
880         if (do_keep && pack_lockfile) {
881                 *pack_lockfile = index_pack_lockfile(cmd.out);
882                 close(cmd.out);
883         }
884
885         if (!use_sideband)
886                 /* Closed by start_command() */
887                 xd[0] = -1;
888
889         ret = finish_command(&cmd);
890         if (!ret || (args->check_self_contained_and_connected && ret == 1))
891                 args->self_contained_and_connected =
892                         args->check_self_contained_and_connected &&
893                         ret == 0;
894         else
895                 die(_("%s failed"), cmd_name);
896         if (use_sideband && finish_async(&demux))
897                 die(_("error in sideband demultiplexer"));
898         return 0;
899 }
900
901 static int cmp_ref_by_name(const void *a_, const void *b_)
902 {
903         const struct ref *a = *((const struct ref **)a_);
904         const struct ref *b = *((const struct ref **)b_);
905         return strcmp(a->name, b->name);
906 }
907
908 static struct ref *do_fetch_pack(struct fetch_pack_args *args,
909                                  int fd[2],
910                                  const struct ref *orig_ref,
911                                  struct ref **sought, int nr_sought,
912                                  struct shallow_info *si,
913                                  char **pack_lockfile)
914 {
915         struct ref *ref = copy_ref_list(orig_ref);
916         struct object_id oid;
917         const char *agent_feature;
918         int agent_len;
919
920         sort_ref_list(&ref, ref_compare_name);
921         QSORT(sought, nr_sought, cmp_ref_by_name);
922
923         if ((args->depth > 0 || is_repository_shallow()) && !server_supports("shallow"))
924                 die(_("Server does not support shallow clients"));
925         if (args->depth > 0 || args->deepen_since || args->deepen_not)
926                 args->deepen = 1;
927         if (server_supports("multi_ack_detailed")) {
928                 print_verbose(args, _("Server supports multi_ack_detailed"));
929                 multi_ack = 2;
930                 if (server_supports("no-done")) {
931                         print_verbose(args, _("Server supports no-done"));
932                         if (args->stateless_rpc)
933                                 no_done = 1;
934                 }
935         }
936         else if (server_supports("multi_ack")) {
937                 print_verbose(args, _("Server supports multi_ack"));
938                 multi_ack = 1;
939         }
940         if (server_supports("side-band-64k")) {
941                 print_verbose(args, _("Server supports side-band-64k"));
942                 use_sideband = 2;
943         }
944         else if (server_supports("side-band")) {
945                 print_verbose(args, _("Server supports side-band"));
946                 use_sideband = 1;
947         }
948         if (server_supports("allow-tip-sha1-in-want")) {
949                 print_verbose(args, _("Server supports allow-tip-sha1-in-want"));
950                 allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
951         }
952         if (server_supports("allow-reachable-sha1-in-want")) {
953                 print_verbose(args, _("Server supports allow-reachable-sha1-in-want"));
954                 allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
955         }
956         if (!server_supports("thin-pack"))
957                 args->use_thin_pack = 0;
958         if (!server_supports("no-progress"))
959                 args->no_progress = 0;
960         if (!server_supports("include-tag"))
961                 args->include_tag = 0;
962         if (server_supports("ofs-delta"))
963                 print_verbose(args, _("Server supports ofs-delta"));
964         else
965                 prefer_ofs_delta = 0;
966
967         if ((agent_feature = server_feature_value("agent", &agent_len))) {
968                 agent_supported = 1;
969                 if (agent_len)
970                         print_verbose(args, _("Server version is %.*s"),
971                                       agent_len, agent_feature);
972         }
973         if (server_supports("deepen-since"))
974                 deepen_since_ok = 1;
975         else if (args->deepen_since)
976                 die(_("Server does not support --shallow-since"));
977         if (server_supports("deepen-not"))
978                 deepen_not_ok = 1;
979         else if (args->deepen_not)
980                 die(_("Server does not support --shallow-exclude"));
981         if (!server_supports("deepen-relative") && args->deepen_relative)
982                 die(_("Server does not support --deepen"));
983
984         if (everything_local(args, &ref, sought, nr_sought)) {
985                 packet_flush(fd[1]);
986                 goto all_done;
987         }
988         if (find_common(args, fd, &oid, ref) < 0)
989                 if (!args->keep_pack)
990                         /* When cloning, it is not unusual to have
991                          * no common commit.
992                          */
993                         warning(_("no common commits"));
994
995         if (args->stateless_rpc)
996                 packet_flush(fd[1]);
997         if (args->deepen)
998                 setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
999                                         NULL);
1000         else if (si->nr_ours || si->nr_theirs)
1001                 alternate_shallow_file = setup_temporary_shallow(si->shallow);
1002         else
1003                 alternate_shallow_file = NULL;
1004         if (get_pack(args, fd, pack_lockfile))
1005                 die(_("git fetch-pack: fetch failed."));
1006
1007  all_done:
1008         return ref;
1009 }
1010
1011 static void fetch_pack_config(void)
1012 {
1013         git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
1014         git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit);
1015         git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta);
1016         git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects);
1017         git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects);
1018
1019         git_config(git_default_config, NULL);
1020 }
1021
1022 static void fetch_pack_setup(void)
1023 {
1024         static int did_setup;
1025         if (did_setup)
1026                 return;
1027         fetch_pack_config();
1028         if (0 <= transfer_unpack_limit)
1029                 unpack_limit = transfer_unpack_limit;
1030         else if (0 <= fetch_unpack_limit)
1031                 unpack_limit = fetch_unpack_limit;
1032         did_setup = 1;
1033 }
1034
1035 static int remove_duplicates_in_refs(struct ref **ref, int nr)
1036 {
1037         struct string_list names = STRING_LIST_INIT_NODUP;
1038         int src, dst;
1039
1040         for (src = dst = 0; src < nr; src++) {
1041                 struct string_list_item *item;
1042                 item = string_list_insert(&names, ref[src]->name);
1043                 if (item->util)
1044                         continue; /* already have it */
1045                 item->util = ref[src];
1046                 if (src != dst)
1047                         ref[dst] = ref[src];
1048                 dst++;
1049         }
1050         for (src = dst; src < nr; src++)
1051                 ref[src] = NULL;
1052         string_list_clear(&names, 0);
1053         return dst;
1054 }
1055
1056 static void update_shallow(struct fetch_pack_args *args,
1057                            struct ref **sought, int nr_sought,
1058                            struct shallow_info *si)
1059 {
1060         struct oid_array ref = OID_ARRAY_INIT;
1061         int *status;
1062         int i;
1063
1064         if (args->deepen && alternate_shallow_file) {
1065                 if (*alternate_shallow_file == '\0') { /* --unshallow */
1066                         unlink_or_warn(git_path_shallow());
1067                         rollback_lock_file(&shallow_lock);
1068                 } else
1069                         commit_lock_file(&shallow_lock);
1070                 return;
1071         }
1072
1073         if (!si->shallow || !si->shallow->nr)
1074                 return;
1075
1076         if (args->cloning) {
1077                 /*
1078                  * remote is shallow, but this is a clone, there are
1079                  * no objects in repo to worry about. Accept any
1080                  * shallow points that exist in the pack (iow in repo
1081                  * after get_pack() and reprepare_packed_git())
1082                  */
1083                 struct oid_array extra = OID_ARRAY_INIT;
1084                 struct object_id *oid = si->shallow->oid;
1085                 for (i = 0; i < si->shallow->nr; i++)
1086                         if (has_object_file(&oid[i]))
1087                                 oid_array_append(&extra, &oid[i]);
1088                 if (extra.nr) {
1089                         setup_alternate_shallow(&shallow_lock,
1090                                                 &alternate_shallow_file,
1091                                                 &extra);
1092                         commit_lock_file(&shallow_lock);
1093                 }
1094                 oid_array_clear(&extra);
1095                 return;
1096         }
1097
1098         if (!si->nr_ours && !si->nr_theirs)
1099                 return;
1100
1101         remove_nonexistent_theirs_shallow(si);
1102         if (!si->nr_ours && !si->nr_theirs)
1103                 return;
1104         for (i = 0; i < nr_sought; i++)
1105                 oid_array_append(&ref, &sought[i]->old_oid);
1106         si->ref = &ref;
1107
1108         if (args->update_shallow) {
1109                 /*
1110                  * remote is also shallow, .git/shallow may be updated
1111                  * so all refs can be accepted. Make sure we only add
1112                  * shallow roots that are actually reachable from new
1113                  * refs.
1114                  */
1115                 struct oid_array extra = OID_ARRAY_INIT;
1116                 struct object_id *oid = si->shallow->oid;
1117                 assign_shallow_commits_to_refs(si, NULL, NULL);
1118                 if (!si->nr_ours && !si->nr_theirs) {
1119                         oid_array_clear(&ref);
1120                         return;
1121                 }
1122                 for (i = 0; i < si->nr_ours; i++)
1123                         oid_array_append(&extra, &oid[si->ours[i]]);
1124                 for (i = 0; i < si->nr_theirs; i++)
1125                         oid_array_append(&extra, &oid[si->theirs[i]]);
1126                 setup_alternate_shallow(&shallow_lock,
1127                                         &alternate_shallow_file,
1128                                         &extra);
1129                 commit_lock_file(&shallow_lock);
1130                 oid_array_clear(&extra);
1131                 oid_array_clear(&ref);
1132                 return;
1133         }
1134
1135         /*
1136          * remote is also shallow, check what ref is safe to update
1137          * without updating .git/shallow
1138          */
1139         status = xcalloc(nr_sought, sizeof(*status));
1140         assign_shallow_commits_to_refs(si, NULL, status);
1141         if (si->nr_ours || si->nr_theirs) {
1142                 for (i = 0; i < nr_sought; i++)
1143                         if (status[i])
1144                                 sought[i]->status = REF_STATUS_REJECT_SHALLOW;
1145         }
1146         free(status);
1147         oid_array_clear(&ref);
1148 }
1149
1150 struct ref *fetch_pack(struct fetch_pack_args *args,
1151                        int fd[], struct child_process *conn,
1152                        const struct ref *ref,
1153                        const char *dest,
1154                        struct ref **sought, int nr_sought,
1155                        struct oid_array *shallow,
1156                        char **pack_lockfile)
1157 {
1158         struct ref *ref_cpy;
1159         struct shallow_info si;
1160
1161         fetch_pack_setup();
1162         if (nr_sought)
1163                 nr_sought = remove_duplicates_in_refs(sought, nr_sought);
1164
1165         if (!ref) {
1166                 packet_flush(fd[1]);
1167                 die(_("no matching remote head"));
1168         }
1169         prepare_shallow_info(&si, shallow);
1170         ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
1171                                 &si, pack_lockfile);
1172         reprepare_packed_git();
1173         update_shallow(args, sought, nr_sought, &si);
1174         clear_shallow_info(&si);
1175         return ref_cpy;
1176 }
1177
1178 int report_unmatched_refs(struct ref **sought, int nr_sought)
1179 {
1180         int i, ret = 0;
1181
1182         for (i = 0; i < nr_sought; i++) {
1183                 if (!sought[i])
1184                         continue;
1185                 switch (sought[i]->match_status) {
1186                 case REF_MATCHED:
1187                         continue;
1188                 case REF_NOT_MATCHED:
1189                         error(_("no such remote ref %s"), sought[i]->name);
1190                         break;
1191                 case REF_UNADVERTISED_NOT_ALLOWED:
1192                         error(_("Server does not allow request for unadvertised object %s"),
1193                               sought[i]->name);
1194                         break;
1195                 }
1196                 ret = 1;
1197         }
1198         return ret;
1199 }