compat/bswap.h: detect endianness on more platforms that don't use BYTE_ORDER
[git] / upload-pack.c
1 #include "cache.h"
2 #include "refs.h"
3 #include "pkt-line.h"
4 #include "sideband.h"
5 #include "tag.h"
6 #include "object.h"
7 #include "commit.h"
8 #include "exec_cmd.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
18 static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=<n>] <dir>";
19
20 /* Remember to update object flag allocation in object.h */
21 #define THEY_HAVE       (1u << 11)
22 #define OUR_REF         (1u << 12)
23 #define WANTED          (1u << 13)
24 #define COMMON_KNOWN    (1u << 14)
25 #define REACHABLE       (1u << 15)
26
27 #define SHALLOW         (1u << 16)
28 #define NOT_SHALLOW     (1u << 17)
29 #define CLIENT_SHALLOW  (1u << 18)
30 #define HIDDEN_REF      (1u << 19)
31
32 static unsigned long oldest_have;
33
34 static int multi_ack;
35 static int no_done;
36 static int use_thin_pack, use_ofs_delta, use_include_tag;
37 static int no_progress, daemon_mode;
38 static int allow_tip_sha1_in_want;
39 static int shallow_nr;
40 static struct object_array have_obj;
41 static struct object_array want_obj;
42 static struct object_array extra_edge_obj;
43 static unsigned int timeout;
44 static int keepalive = 5;
45 /* 0 for no sideband,
46  * otherwise maximum packet size (up to 65520 bytes).
47  */
48 static int use_sideband;
49 static int advertise_refs;
50 static int stateless_rpc;
51
52 static void reset_timeout(void)
53 {
54         alarm(timeout);
55 }
56
57 static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
58 {
59         if (use_sideband)
60                 return send_sideband(1, fd, data, sz, use_sideband);
61         if (fd == 3)
62                 /* emergency quit */
63                 fd = 2;
64         if (fd == 2) {
65                 /* XXX: are we happy to lose stuff here? */
66                 xwrite(fd, data, sz);
67                 return sz;
68         }
69         write_or_die(fd, data, sz);
70         return sz;
71 }
72
73 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
74 {
75         FILE *fp = cb_data;
76         if (graft->nr_parent == -1)
77                 fprintf(fp, "--shallow %s\n", sha1_to_hex(graft->sha1));
78         return 0;
79 }
80
81 static void create_pack_file(void)
82 {
83         struct child_process pack_objects;
84         char data[8193], progress[128];
85         char abort_msg[] = "aborting due to possible repository "
86                 "corruption on the remote side.";
87         int buffered = -1;
88         ssize_t sz;
89         const char *argv[12];
90         int i, arg = 0;
91         FILE *pipe_fd;
92
93         if (shallow_nr) {
94                 argv[arg++] = "--shallow-file";
95                 argv[arg++] = "";
96         }
97         argv[arg++] = "pack-objects";
98         argv[arg++] = "--revs";
99         if (use_thin_pack)
100                 argv[arg++] = "--thin";
101
102         argv[arg++] = "--stdout";
103         if (!no_progress)
104                 argv[arg++] = "--progress";
105         if (use_ofs_delta)
106                 argv[arg++] = "--delta-base-offset";
107         if (use_include_tag)
108                 argv[arg++] = "--include-tag";
109         argv[arg++] = NULL;
110
111         memset(&pack_objects, 0, sizeof(pack_objects));
112         pack_objects.in = -1;
113         pack_objects.out = -1;
114         pack_objects.err = -1;
115         pack_objects.git_cmd = 1;
116         pack_objects.argv = argv;
117
118         if (start_command(&pack_objects))
119                 die("git upload-pack: unable to fork git-pack-objects");
120
121         pipe_fd = xfdopen(pack_objects.in, "w");
122
123         if (shallow_nr)
124                 for_each_commit_graft(write_one_shallow, pipe_fd);
125
126         for (i = 0; i < want_obj.nr; i++)
127                 fprintf(pipe_fd, "%s\n",
128                         sha1_to_hex(want_obj.objects[i].item->sha1));
129         fprintf(pipe_fd, "--not\n");
130         for (i = 0; i < have_obj.nr; i++)
131                 fprintf(pipe_fd, "%s\n",
132                         sha1_to_hex(have_obj.objects[i].item->sha1));
133         for (i = 0; i < extra_edge_obj.nr; i++)
134                 fprintf(pipe_fd, "%s\n",
135                         sha1_to_hex(extra_edge_obj.objects[i].item->sha1));
136         fprintf(pipe_fd, "\n");
137         fflush(pipe_fd);
138         fclose(pipe_fd);
139
140         /* We read from pack_objects.err to capture stderr output for
141          * progress bar, and pack_objects.out to capture the pack data.
142          */
143
144         while (1) {
145                 struct pollfd pfd[2];
146                 int pe, pu, pollsize;
147                 int ret;
148
149                 reset_timeout();
150
151                 pollsize = 0;
152                 pe = pu = -1;
153
154                 if (0 <= pack_objects.out) {
155                         pfd[pollsize].fd = pack_objects.out;
156                         pfd[pollsize].events = POLLIN;
157                         pu = pollsize;
158                         pollsize++;
159                 }
160                 if (0 <= pack_objects.err) {
161                         pfd[pollsize].fd = pack_objects.err;
162                         pfd[pollsize].events = POLLIN;
163                         pe = pollsize;
164                         pollsize++;
165                 }
166
167                 if (!pollsize)
168                         break;
169
170                 ret = poll(pfd, pollsize, 1000 * keepalive);
171                 if (ret < 0) {
172                         if (errno != EINTR) {
173                                 error("poll failed, resuming: %s",
174                                       strerror(errno));
175                                 sleep(1);
176                         }
177                         continue;
178                 }
179                 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
180                         /* Status ready; we ship that in the side-band
181                          * or dump to the standard error.
182                          */
183                         sz = xread(pack_objects.err, progress,
184                                   sizeof(progress));
185                         if (0 < sz)
186                                 send_client_data(2, progress, sz);
187                         else if (sz == 0) {
188                                 close(pack_objects.err);
189                                 pack_objects.err = -1;
190                         }
191                         else
192                                 goto fail;
193                         /* give priority to status messages */
194                         continue;
195                 }
196                 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
197                         /* Data ready; we keep the last byte to ourselves
198                          * in case we detect broken rev-list, so that we
199                          * can leave the stream corrupted.  This is
200                          * unfortunate -- unpack-objects would happily
201                          * accept a valid packdata with trailing garbage,
202                          * so appending garbage after we pass all the
203                          * pack data is not good enough to signal
204                          * breakage to downstream.
205                          */
206                         char *cp = data;
207                         ssize_t outsz = 0;
208                         if (0 <= buffered) {
209                                 *cp++ = buffered;
210                                 outsz++;
211                         }
212                         sz = xread(pack_objects.out, cp,
213                                   sizeof(data) - outsz);
214                         if (0 < sz)
215                                 ;
216                         else if (sz == 0) {
217                                 close(pack_objects.out);
218                                 pack_objects.out = -1;
219                         }
220                         else
221                                 goto fail;
222                         sz += outsz;
223                         if (1 < sz) {
224                                 buffered = data[sz-1] & 0xFF;
225                                 sz--;
226                         }
227                         else
228                                 buffered = -1;
229                         sz = send_client_data(1, data, sz);
230                         if (sz < 0)
231                                 goto fail;
232                 }
233
234                 /*
235                  * We hit the keepalive timeout without saying anything; send
236                  * an empty message on the data sideband just to let the other
237                  * side know we're still working on it, but don't have any data
238                  * yet.
239                  *
240                  * If we don't have a sideband channel, there's no room in the
241                  * protocol to say anything, so those clients are just out of
242                  * luck.
243                  */
244                 if (!ret && use_sideband) {
245                         static const char buf[] = "0005\1";
246                         write_or_die(1, buf, 5);
247                 }
248         }
249
250         if (finish_command(&pack_objects)) {
251                 error("git upload-pack: git-pack-objects died with error.");
252                 goto fail;
253         }
254
255         /* flush the data */
256         if (0 <= buffered) {
257                 data[0] = buffered;
258                 sz = send_client_data(1, data, 1);
259                 if (sz < 0)
260                         goto fail;
261                 fprintf(stderr, "flushed.\n");
262         }
263         if (use_sideband)
264                 packet_flush(1);
265         return;
266
267  fail:
268         send_client_data(3, abort_msg, sizeof(abort_msg));
269         die("git upload-pack: %s", abort_msg);
270 }
271
272 static int got_sha1(char *hex, unsigned char *sha1)
273 {
274         struct object *o;
275         int we_knew_they_have = 0;
276
277         if (get_sha1_hex(hex, sha1))
278                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
279         if (!has_sha1_file(sha1))
280                 return -1;
281
282         o = parse_object(sha1);
283         if (!o)
284                 die("oops (%s)", sha1_to_hex(sha1));
285         if (o->type == OBJ_COMMIT) {
286                 struct commit_list *parents;
287                 struct commit *commit = (struct commit *)o;
288                 if (o->flags & THEY_HAVE)
289                         we_knew_they_have = 1;
290                 else
291                         o->flags |= THEY_HAVE;
292                 if (!oldest_have || (commit->date < oldest_have))
293                         oldest_have = commit->date;
294                 for (parents = commit->parents;
295                      parents;
296                      parents = parents->next)
297                         parents->item->object.flags |= THEY_HAVE;
298         }
299         if (!we_knew_they_have) {
300                 add_object_array(o, NULL, &have_obj);
301                 return 1;
302         }
303         return 0;
304 }
305
306 static int reachable(struct commit *want)
307 {
308         struct commit_list *work = NULL;
309
310         commit_list_insert_by_date(want, &work);
311         while (work) {
312                 struct commit_list *list = work->next;
313                 struct commit *commit = work->item;
314                 free(work);
315                 work = list;
316
317                 if (commit->object.flags & THEY_HAVE) {
318                         want->object.flags |= COMMON_KNOWN;
319                         break;
320                 }
321                 if (!commit->object.parsed)
322                         parse_object(commit->object.sha1);
323                 if (commit->object.flags & REACHABLE)
324                         continue;
325                 commit->object.flags |= REACHABLE;
326                 if (commit->date < oldest_have)
327                         continue;
328                 for (list = commit->parents; list; list = list->next) {
329                         struct commit *parent = list->item;
330                         if (!(parent->object.flags & REACHABLE))
331                                 commit_list_insert_by_date(parent, &work);
332                 }
333         }
334         want->object.flags |= REACHABLE;
335         clear_commit_marks(want, REACHABLE);
336         free_commit_list(work);
337         return (want->object.flags & COMMON_KNOWN);
338 }
339
340 static int ok_to_give_up(void)
341 {
342         int i;
343
344         if (!have_obj.nr)
345                 return 0;
346
347         for (i = 0; i < want_obj.nr; i++) {
348                 struct object *want = want_obj.objects[i].item;
349
350                 if (want->flags & COMMON_KNOWN)
351                         continue;
352                 want = deref_tag(want, "a want line", 0);
353                 if (!want || want->type != OBJ_COMMIT) {
354                         /* no way to tell if this is reachable by
355                          * looking at the ancestry chain alone, so
356                          * leave a note to ourselves not to worry about
357                          * this object anymore.
358                          */
359                         want_obj.objects[i].item->flags |= COMMON_KNOWN;
360                         continue;
361                 }
362                 if (!reachable((struct commit *)want))
363                         return 0;
364         }
365         return 1;
366 }
367
368 static int get_common_commits(void)
369 {
370         unsigned char sha1[20];
371         char last_hex[41];
372         int got_common = 0;
373         int got_other = 0;
374         int sent_ready = 0;
375
376         save_commit_buffer = 0;
377
378         for (;;) {
379                 char *line = packet_read_line(0, NULL);
380                 reset_timeout();
381
382                 if (!line) {
383                         if (multi_ack == 2 && got_common
384                             && !got_other && ok_to_give_up()) {
385                                 sent_ready = 1;
386                                 packet_write(1, "ACK %s ready\n", last_hex);
387                         }
388                         if (have_obj.nr == 0 || multi_ack)
389                                 packet_write(1, "NAK\n");
390
391                         if (no_done && sent_ready) {
392                                 packet_write(1, "ACK %s\n", last_hex);
393                                 return 0;
394                         }
395                         if (stateless_rpc)
396                                 exit(0);
397                         got_common = 0;
398                         got_other = 0;
399                         continue;
400                 }
401                 if (starts_with(line, "have ")) {
402                         switch (got_sha1(line+5, sha1)) {
403                         case -1: /* they have what we do not */
404                                 got_other = 1;
405                                 if (multi_ack && ok_to_give_up()) {
406                                         const char *hex = sha1_to_hex(sha1);
407                                         if (multi_ack == 2) {
408                                                 sent_ready = 1;
409                                                 packet_write(1, "ACK %s ready\n", hex);
410                                         } else
411                                                 packet_write(1, "ACK %s continue\n", hex);
412                                 }
413                                 break;
414                         default:
415                                 got_common = 1;
416                                 memcpy(last_hex, sha1_to_hex(sha1), 41);
417                                 if (multi_ack == 2)
418                                         packet_write(1, "ACK %s common\n", last_hex);
419                                 else if (multi_ack)
420                                         packet_write(1, "ACK %s continue\n", last_hex);
421                                 else if (have_obj.nr == 1)
422                                         packet_write(1, "ACK %s\n", last_hex);
423                                 break;
424                         }
425                         continue;
426                 }
427                 if (!strcmp(line, "done")) {
428                         if (have_obj.nr > 0) {
429                                 if (multi_ack)
430                                         packet_write(1, "ACK %s\n", last_hex);
431                                 return 0;
432                         }
433                         packet_write(1, "NAK\n");
434                         return -1;
435                 }
436                 die("git upload-pack: expected SHA1 list, got '%s'", line);
437         }
438 }
439
440 static int is_our_ref(struct object *o)
441 {
442         return o->flags &
443                 ((allow_tip_sha1_in_want ? HIDDEN_REF : 0) | OUR_REF);
444 }
445
446 static void check_non_tip(void)
447 {
448         static const char *argv[] = {
449                 "rev-list", "--stdin", NULL,
450         };
451         static struct child_process cmd;
452         struct object *o;
453         char namebuf[42]; /* ^ + SHA-1 + LF */
454         int i;
455
456         /* In the normal in-process case non-tip request can never happen */
457         if (!stateless_rpc)
458                 goto error;
459
460         cmd.argv = argv;
461         cmd.git_cmd = 1;
462         cmd.no_stderr = 1;
463         cmd.in = -1;
464         cmd.out = -1;
465
466         if (start_command(&cmd))
467                 goto error;
468
469         /*
470          * If rev-list --stdin encounters an unknown commit, it
471          * terminates, which will cause SIGPIPE in the write loop
472          * below.
473          */
474         sigchain_push(SIGPIPE, SIG_IGN);
475
476         namebuf[0] = '^';
477         namebuf[41] = '\n';
478         for (i = get_max_object_index(); 0 < i; ) {
479                 o = get_indexed_object(--i);
480                 if (!o)
481                         continue;
482                 if (!is_our_ref(o))
483                         continue;
484                 memcpy(namebuf + 1, sha1_to_hex(o->sha1), 40);
485                 if (write_in_full(cmd.in, namebuf, 42) < 0)
486                         goto error;
487         }
488         namebuf[40] = '\n';
489         for (i = 0; i < want_obj.nr; i++) {
490                 o = want_obj.objects[i].item;
491                 if (is_our_ref(o))
492                         continue;
493                 memcpy(namebuf, sha1_to_hex(o->sha1), 40);
494                 if (write_in_full(cmd.in, namebuf, 41) < 0)
495                         goto error;
496         }
497         close(cmd.in);
498
499         sigchain_pop(SIGPIPE);
500
501         /*
502          * The commits out of the rev-list are not ancestors of
503          * our ref.
504          */
505         i = read_in_full(cmd.out, namebuf, 1);
506         if (i)
507                 goto error;
508         close(cmd.out);
509
510         /*
511          * rev-list may have died by encountering a bad commit
512          * in the history, in which case we do want to bail out
513          * even when it showed no commit.
514          */
515         if (finish_command(&cmd))
516                 goto error;
517
518         /* All the non-tip ones are ancestors of what we advertised */
519         return;
520
521 error:
522         /* Pick one of them (we know there at least is one) */
523         for (i = 0; i < want_obj.nr; i++) {
524                 o = want_obj.objects[i].item;
525                 if (!is_our_ref(o))
526                         die("git upload-pack: not our ref %s",
527                             sha1_to_hex(o->sha1));
528         }
529 }
530
531 static void receive_needs(void)
532 {
533         struct object_array shallows = OBJECT_ARRAY_INIT;
534         int depth = 0;
535         int has_non_tip = 0;
536
537         shallow_nr = 0;
538         for (;;) {
539                 struct object *o;
540                 const char *features;
541                 unsigned char sha1_buf[20];
542                 char *line = packet_read_line(0, NULL);
543                 reset_timeout();
544                 if (!line)
545                         break;
546
547                 if (starts_with(line, "shallow ")) {
548                         unsigned char sha1[20];
549                         struct object *object;
550                         if (get_sha1_hex(line + 8, sha1))
551                                 die("invalid shallow line: %s", line);
552                         object = parse_object(sha1);
553                         if (!object)
554                                 continue;
555                         if (object->type != OBJ_COMMIT)
556                                 die("invalid shallow object %s", sha1_to_hex(sha1));
557                         if (!(object->flags & CLIENT_SHALLOW)) {
558                                 object->flags |= CLIENT_SHALLOW;
559                                 add_object_array(object, NULL, &shallows);
560                         }
561                         continue;
562                 }
563                 if (starts_with(line, "deepen ")) {
564                         char *end;
565                         depth = strtol(line + 7, &end, 0);
566                         if (end == line + 7 || depth <= 0)
567                                 die("Invalid deepen: %s", line);
568                         continue;
569                 }
570                 if (!starts_with(line, "want ") ||
571                     get_sha1_hex(line+5, sha1_buf))
572                         die("git upload-pack: protocol error, "
573                             "expected to get sha, not '%s'", line);
574
575                 features = line + 45;
576
577                 if (parse_feature_request(features, "multi_ack_detailed"))
578                         multi_ack = 2;
579                 else if (parse_feature_request(features, "multi_ack"))
580                         multi_ack = 1;
581                 if (parse_feature_request(features, "no-done"))
582                         no_done = 1;
583                 if (parse_feature_request(features, "thin-pack"))
584                         use_thin_pack = 1;
585                 if (parse_feature_request(features, "ofs-delta"))
586                         use_ofs_delta = 1;
587                 if (parse_feature_request(features, "side-band-64k"))
588                         use_sideband = LARGE_PACKET_MAX;
589                 else if (parse_feature_request(features, "side-band"))
590                         use_sideband = DEFAULT_PACKET_MAX;
591                 if (parse_feature_request(features, "no-progress"))
592                         no_progress = 1;
593                 if (parse_feature_request(features, "include-tag"))
594                         use_include_tag = 1;
595
596                 o = parse_object(sha1_buf);
597                 if (!o)
598                         die("git upload-pack: not our ref %s",
599                             sha1_to_hex(sha1_buf));
600                 if (!(o->flags & WANTED)) {
601                         o->flags |= WANTED;
602                         if (!is_our_ref(o))
603                                 has_non_tip = 1;
604                         add_object_array(o, NULL, &want_obj);
605                 }
606         }
607
608         /*
609          * We have sent all our refs already, and the other end
610          * should have chosen out of them. When we are operating
611          * in the stateless RPC mode, however, their choice may
612          * have been based on the set of older refs advertised
613          * by another process that handled the initial request.
614          */
615         if (has_non_tip)
616                 check_non_tip();
617
618         if (!use_sideband && daemon_mode)
619                 no_progress = 1;
620
621         if (depth == 0 && shallows.nr == 0)
622                 return;
623         if (depth > 0) {
624                 struct commit_list *result = NULL, *backup = NULL;
625                 int i;
626                 if (depth == INFINITE_DEPTH && !is_repository_shallow())
627                         for (i = 0; i < shallows.nr; i++) {
628                                 struct object *object = shallows.objects[i].item;
629                                 object->flags |= NOT_SHALLOW;
630                         }
631                 else
632                         backup = result =
633                                 get_shallow_commits(&want_obj, depth,
634                                                     SHALLOW, NOT_SHALLOW);
635                 while (result) {
636                         struct object *object = &result->item->object;
637                         if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
638                                 packet_write(1, "shallow %s",
639                                                 sha1_to_hex(object->sha1));
640                                 register_shallow(object->sha1);
641                                 shallow_nr++;
642                         }
643                         result = result->next;
644                 }
645                 free_commit_list(backup);
646                 for (i = 0; i < shallows.nr; i++) {
647                         struct object *object = shallows.objects[i].item;
648                         if (object->flags & NOT_SHALLOW) {
649                                 struct commit_list *parents;
650                                 packet_write(1, "unshallow %s",
651                                         sha1_to_hex(object->sha1));
652                                 object->flags &= ~CLIENT_SHALLOW;
653                                 /* make sure the real parents are parsed */
654                                 unregister_shallow(object->sha1);
655                                 object->parsed = 0;
656                                 parse_commit_or_die((struct commit *)object);
657                                 parents = ((struct commit *)object)->parents;
658                                 while (parents) {
659                                         add_object_array(&parents->item->object,
660                                                         NULL, &want_obj);
661                                         parents = parents->next;
662                                 }
663                                 add_object_array(object, NULL, &extra_edge_obj);
664                         }
665                         /* make sure commit traversal conforms to client */
666                         register_shallow(object->sha1);
667                 }
668                 packet_flush(1);
669         } else
670                 if (shallows.nr > 0) {
671                         int i;
672                         for (i = 0; i < shallows.nr; i++)
673                                 register_shallow(shallows.objects[i].item->sha1);
674                 }
675
676         shallow_nr += shallows.nr;
677         free(shallows.objects);
678 }
679
680 /* return non-zero if the ref is hidden, otherwise 0 */
681 static int mark_our_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
682 {
683         struct object *o = lookup_unknown_object(sha1);
684
685         if (ref_is_hidden(refname)) {
686                 o->flags |= HIDDEN_REF;
687                 return 1;
688         }
689         if (!o)
690                 die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));
691         o->flags |= OUR_REF;
692         return 0;
693 }
694
695 static void format_symref_info(struct strbuf *buf, struct string_list *symref)
696 {
697         struct string_list_item *item;
698
699         if (!symref->nr)
700                 return;
701         for_each_string_list_item(item, symref)
702                 strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util);
703 }
704
705 static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
706 {
707         static const char *capabilities = "multi_ack thin-pack side-band"
708                 " side-band-64k ofs-delta shallow no-progress"
709                 " include-tag multi_ack_detailed";
710         const char *refname_nons = strip_namespace(refname);
711         unsigned char peeled[20];
712
713         if (mark_our_ref(refname, sha1, flag, NULL))
714                 return 0;
715
716         if (capabilities) {
717                 struct strbuf symref_info = STRBUF_INIT;
718
719                 format_symref_info(&symref_info, cb_data);
720                 packet_write(1, "%s %s%c%s%s%s%s agent=%s\n",
721                              sha1_to_hex(sha1), refname_nons,
722                              0, capabilities,
723                              allow_tip_sha1_in_want ? " allow-tip-sha1-in-want" : "",
724                              stateless_rpc ? " no-done" : "",
725                              symref_info.buf,
726                              git_user_agent_sanitized());
727                 strbuf_release(&symref_info);
728         } else {
729                 packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname_nons);
730         }
731         capabilities = NULL;
732         if (!peel_ref(refname, peeled))
733                 packet_write(1, "%s %s^{}\n", sha1_to_hex(peeled), refname_nons);
734         return 0;
735 }
736
737 static int find_symref(const char *refname, const unsigned char *sha1, int flag,
738                        void *cb_data)
739 {
740         const char *symref_target;
741         struct string_list_item *item;
742         unsigned char unused[20];
743
744         if ((flag & REF_ISSYMREF) == 0)
745                 return 0;
746         symref_target = resolve_ref_unsafe(refname, unused, 0, &flag);
747         if (!symref_target || (flag & REF_ISSYMREF) == 0)
748                 die("'%s' is a symref but it is not?", refname);
749         item = string_list_append(cb_data, refname);
750         item->util = xstrdup(symref_target);
751         return 0;
752 }
753
754 static void upload_pack(void)
755 {
756         struct string_list symref = STRING_LIST_INIT_DUP;
757
758         head_ref_namespaced(find_symref, &symref);
759
760         if (advertise_refs || !stateless_rpc) {
761                 reset_timeout();
762                 head_ref_namespaced(send_ref, &symref);
763                 for_each_namespaced_ref(send_ref, &symref);
764                 advertise_shallow_grafts(1);
765                 packet_flush(1);
766         } else {
767                 head_ref_namespaced(mark_our_ref, NULL);
768                 for_each_namespaced_ref(mark_our_ref, NULL);
769         }
770         string_list_clear(&symref, 1);
771         if (advertise_refs)
772                 return;
773
774         receive_needs();
775         if (want_obj.nr) {
776                 get_common_commits();
777                 create_pack_file();
778         }
779 }
780
781 static int upload_pack_config(const char *var, const char *value, void *unused)
782 {
783         if (!strcmp("uploadpack.allowtipsha1inwant", var))
784                 allow_tip_sha1_in_want = git_config_bool(var, value);
785         else if (!strcmp("uploadpack.keepalive", var)) {
786                 keepalive = git_config_int(var, value);
787                 if (!keepalive)
788                         keepalive = -1;
789         }
790         return parse_hide_refs_config(var, value, "uploadpack");
791 }
792
793 int main(int argc, char **argv)
794 {
795         char *dir;
796         int i;
797         int strict = 0;
798
799         git_setup_gettext();
800
801         packet_trace_identity("upload-pack");
802         git_extract_argv0_path(argv[0]);
803         check_replace_refs = 0;
804
805         for (i = 1; i < argc; i++) {
806                 char *arg = argv[i];
807
808                 if (arg[0] != '-')
809                         break;
810                 if (!strcmp(arg, "--advertise-refs")) {
811                         advertise_refs = 1;
812                         continue;
813                 }
814                 if (!strcmp(arg, "--stateless-rpc")) {
815                         stateless_rpc = 1;
816                         continue;
817                 }
818                 if (!strcmp(arg, "--strict")) {
819                         strict = 1;
820                         continue;
821                 }
822                 if (starts_with(arg, "--timeout=")) {
823                         timeout = atoi(arg+10);
824                         daemon_mode = 1;
825                         continue;
826                 }
827                 if (!strcmp(arg, "--")) {
828                         i++;
829                         break;
830                 }
831         }
832
833         if (i != argc-1)
834                 usage(upload_pack_usage);
835
836         setup_path();
837
838         dir = argv[i];
839
840         if (!enter_repo(dir, strict))
841                 die("'%s' does not appear to be a git repository", dir);
842
843         git_config(upload_pack_config, NULL);
844         upload_pack();
845         return 0;
846 }