builtin-notes: Add "append" subcommand for appending to note objects
[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
14 static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=nn] <dir>";
15
16 /* bits #0..7 in revision.h, #8..10 in commit.c */
17 #define THEY_HAVE       (1u << 11)
18 #define OUR_REF         (1u << 12)
19 #define WANTED          (1u << 13)
20 #define COMMON_KNOWN    (1u << 14)
21 #define REACHABLE       (1u << 15)
22
23 #define SHALLOW         (1u << 16)
24 #define NOT_SHALLOW     (1u << 17)
25 #define CLIENT_SHALLOW  (1u << 18)
26
27 static unsigned long oldest_have;
28
29 static int multi_ack, nr_our_refs;
30 static int use_thin_pack, use_ofs_delta, use_include_tag;
31 static int no_progress, daemon_mode;
32 static int shallow_nr;
33 static struct object_array have_obj;
34 static struct object_array want_obj;
35 static struct object_array extra_edge_obj;
36 static unsigned int timeout;
37 /* 0 for no sideband,
38  * otherwise maximum packet size (up to 65520 bytes).
39  */
40 static int use_sideband;
41 static int debug_fd;
42 static int advertise_refs;
43 static int stateless_rpc;
44
45 static void reset_timeout(void)
46 {
47         alarm(timeout);
48 }
49
50 static int strip(char *line, int len)
51 {
52         if (len && line[len-1] == '\n')
53                 line[--len] = 0;
54         return len;
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         return safe_write(fd, data, sz);
70 }
71
72 static FILE *pack_pipe = NULL;
73 static void show_commit(struct commit *commit, void *data)
74 {
75         if (commit->object.flags & BOUNDARY)
76                 fputc('-', pack_pipe);
77         if (fputs(sha1_to_hex(commit->object.sha1), pack_pipe) < 0)
78                 die("broken output pipe");
79         fputc('\n', pack_pipe);
80         fflush(pack_pipe);
81         free(commit->buffer);
82         commit->buffer = NULL;
83 }
84
85 static void show_object(struct object *obj, const struct name_path *path, const char *component)
86 {
87         /* An object with name "foo\n0000000..." can be used to
88          * confuse downstream git-pack-objects very badly.
89          */
90         const char *name = path_name(path, component);
91         const char *ep = strchr(name, '\n');
92         if (ep) {
93                 fprintf(pack_pipe, "%s %.*s\n", sha1_to_hex(obj->sha1),
94                        (int) (ep - name),
95                        name);
96         }
97         else
98                 fprintf(pack_pipe, "%s %s\n",
99                                 sha1_to_hex(obj->sha1), name);
100         free((char *)name);
101 }
102
103 static void show_edge(struct commit *commit)
104 {
105         fprintf(pack_pipe, "-%s\n", sha1_to_hex(commit->object.sha1));
106 }
107
108 static int do_rev_list(int fd, void *create_full_pack)
109 {
110         int i;
111         struct rev_info revs;
112
113         pack_pipe = xfdopen(fd, "w");
114         init_revisions(&revs, NULL);
115         revs.tag_objects = 1;
116         revs.tree_objects = 1;
117         revs.blob_objects = 1;
118         if (use_thin_pack)
119                 revs.edge_hint = 1;
120
121         if (create_full_pack) {
122                 const char *args[] = {"rev-list", "--all", NULL};
123                 setup_revisions(2, args, &revs, NULL);
124         } else {
125                 for (i = 0; i < want_obj.nr; i++) {
126                         struct object *o = want_obj.objects[i].item;
127                         /* why??? */
128                         o->flags &= ~UNINTERESTING;
129                         add_pending_object(&revs, o, NULL);
130                 }
131                 for (i = 0; i < have_obj.nr; i++) {
132                         struct object *o = have_obj.objects[i].item;
133                         o->flags |= UNINTERESTING;
134                         add_pending_object(&revs, o, NULL);
135                 }
136                 setup_revisions(0, NULL, &revs, NULL);
137         }
138         if (prepare_revision_walk(&revs))
139                 die("revision walk setup failed");
140         mark_edges_uninteresting(revs.commits, &revs, show_edge);
141         if (use_thin_pack)
142                 for (i = 0; i < extra_edge_obj.nr; i++)
143                         fprintf(pack_pipe, "-%s\n", sha1_to_hex(
144                                         extra_edge_obj.objects[i].item->sha1));
145         traverse_commit_list(&revs, show_commit, show_object, NULL);
146         fflush(pack_pipe);
147         fclose(pack_pipe);
148         return 0;
149 }
150
151 static void create_pack_file(void)
152 {
153         struct async rev_list;
154         struct child_process pack_objects;
155         int create_full_pack = (nr_our_refs == want_obj.nr && !have_obj.nr);
156         char data[8193], progress[128];
157         char abort_msg[] = "aborting due to possible repository "
158                 "corruption on the remote side.";
159         int buffered = -1;
160         ssize_t sz;
161         const char *argv[10];
162         int arg = 0;
163
164         if (shallow_nr) {
165                 rev_list.proc = do_rev_list;
166                 rev_list.data = 0;
167                 if (start_async(&rev_list))
168                         die("git upload-pack: unable to fork git-rev-list");
169                 argv[arg++] = "pack-objects";
170         } else {
171                 argv[arg++] = "pack-objects";
172                 argv[arg++] = "--revs";
173                 if (create_full_pack)
174                         argv[arg++] = "--all";
175                 else if (use_thin_pack)
176                         argv[arg++] = "--thin";
177         }
178
179         argv[arg++] = "--stdout";
180         if (!no_progress)
181                 argv[arg++] = "--progress";
182         if (use_ofs_delta)
183                 argv[arg++] = "--delta-base-offset";
184         if (use_include_tag)
185                 argv[arg++] = "--include-tag";
186         argv[arg++] = NULL;
187
188         memset(&pack_objects, 0, sizeof(pack_objects));
189         pack_objects.in = shallow_nr ? rev_list.out : -1;
190         pack_objects.out = -1;
191         pack_objects.err = -1;
192         pack_objects.git_cmd = 1;
193         pack_objects.argv = argv;
194
195         if (start_command(&pack_objects))
196                 die("git upload-pack: unable to fork git-pack-objects");
197
198         /* pass on revisions we (don't) want */
199         if (!shallow_nr) {
200                 FILE *pipe_fd = xfdopen(pack_objects.in, "w");
201                 if (!create_full_pack) {
202                         int i;
203                         for (i = 0; i < want_obj.nr; i++)
204                                 fprintf(pipe_fd, "%s\n", sha1_to_hex(want_obj.objects[i].item->sha1));
205                         fprintf(pipe_fd, "--not\n");
206                         for (i = 0; i < have_obj.nr; i++)
207                                 fprintf(pipe_fd, "%s\n", sha1_to_hex(have_obj.objects[i].item->sha1));
208                 }
209
210                 fprintf(pipe_fd, "\n");
211                 fflush(pipe_fd);
212                 fclose(pipe_fd);
213         }
214
215
216         /* We read from pack_objects.err to capture stderr output for
217          * progress bar, and pack_objects.out to capture the pack data.
218          */
219
220         while (1) {
221                 struct pollfd pfd[2];
222                 int pe, pu, pollsize;
223
224                 reset_timeout();
225
226                 pollsize = 0;
227                 pe = pu = -1;
228
229                 if (0 <= pack_objects.out) {
230                         pfd[pollsize].fd = pack_objects.out;
231                         pfd[pollsize].events = POLLIN;
232                         pu = pollsize;
233                         pollsize++;
234                 }
235                 if (0 <= pack_objects.err) {
236                         pfd[pollsize].fd = pack_objects.err;
237                         pfd[pollsize].events = POLLIN;
238                         pe = pollsize;
239                         pollsize++;
240                 }
241
242                 if (!pollsize)
243                         break;
244
245                 if (poll(pfd, pollsize, -1) < 0) {
246                         if (errno != EINTR) {
247                                 error("poll failed, resuming: %s",
248                                       strerror(errno));
249                                 sleep(1);
250                         }
251                         continue;
252                 }
253                 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
254                         /* Status ready; we ship that in the side-band
255                          * or dump to the standard error.
256                          */
257                         sz = xread(pack_objects.err, progress,
258                                   sizeof(progress));
259                         if (0 < sz)
260                                 send_client_data(2, progress, sz);
261                         else if (sz == 0) {
262                                 close(pack_objects.err);
263                                 pack_objects.err = -1;
264                         }
265                         else
266                                 goto fail;
267                         /* give priority to status messages */
268                         continue;
269                 }
270                 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
271                         /* Data ready; we keep the last byte to ourselves
272                          * in case we detect broken rev-list, so that we
273                          * can leave the stream corrupted.  This is
274                          * unfortunate -- unpack-objects would happily
275                          * accept a valid packdata with trailing garbage,
276                          * so appending garbage after we pass all the
277                          * pack data is not good enough to signal
278                          * breakage to downstream.
279                          */
280                         char *cp = data;
281                         ssize_t outsz = 0;
282                         if (0 <= buffered) {
283                                 *cp++ = buffered;
284                                 outsz++;
285                         }
286                         sz = xread(pack_objects.out, cp,
287                                   sizeof(data) - outsz);
288                         if (0 < sz)
289                                 ;
290                         else if (sz == 0) {
291                                 close(pack_objects.out);
292                                 pack_objects.out = -1;
293                         }
294                         else
295                                 goto fail;
296                         sz += outsz;
297                         if (1 < sz) {
298                                 buffered = data[sz-1] & 0xFF;
299                                 sz--;
300                         }
301                         else
302                                 buffered = -1;
303                         sz = send_client_data(1, data, sz);
304                         if (sz < 0)
305                                 goto fail;
306                 }
307         }
308
309         if (finish_command(&pack_objects)) {
310                 error("git upload-pack: git-pack-objects died with error.");
311                 goto fail;
312         }
313         if (shallow_nr && finish_async(&rev_list))
314                 goto fail;      /* error was already reported */
315
316         /* flush the data */
317         if (0 <= buffered) {
318                 data[0] = buffered;
319                 sz = send_client_data(1, data, 1);
320                 if (sz < 0)
321                         goto fail;
322                 fprintf(stderr, "flushed.\n");
323         }
324         if (use_sideband)
325                 packet_flush(1);
326         return;
327
328  fail:
329         send_client_data(3, abort_msg, sizeof(abort_msg));
330         die("git upload-pack: %s", abort_msg);
331 }
332
333 static int got_sha1(char *hex, unsigned char *sha1)
334 {
335         struct object *o;
336         int we_knew_they_have = 0;
337
338         if (get_sha1_hex(hex, sha1))
339                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
340         if (!has_sha1_file(sha1))
341                 return -1;
342
343         o = lookup_object(sha1);
344         if (!(o && o->parsed))
345                 o = parse_object(sha1);
346         if (!o)
347                 die("oops (%s)", sha1_to_hex(sha1));
348         if (o->type == OBJ_COMMIT) {
349                 struct commit_list *parents;
350                 struct commit *commit = (struct commit *)o;
351                 if (o->flags & THEY_HAVE)
352                         we_knew_they_have = 1;
353                 else
354                         o->flags |= THEY_HAVE;
355                 if (!oldest_have || (commit->date < oldest_have))
356                         oldest_have = commit->date;
357                 for (parents = commit->parents;
358                      parents;
359                      parents = parents->next)
360                         parents->item->object.flags |= THEY_HAVE;
361         }
362         if (!we_knew_they_have) {
363                 add_object_array(o, NULL, &have_obj);
364                 return 1;
365         }
366         return 0;
367 }
368
369 static int reachable(struct commit *want)
370 {
371         struct commit_list *work = NULL;
372
373         insert_by_date(want, &work);
374         while (work) {
375                 struct commit_list *list = work->next;
376                 struct commit *commit = work->item;
377                 free(work);
378                 work = list;
379
380                 if (commit->object.flags & THEY_HAVE) {
381                         want->object.flags |= COMMON_KNOWN;
382                         break;
383                 }
384                 if (!commit->object.parsed)
385                         parse_object(commit->object.sha1);
386                 if (commit->object.flags & REACHABLE)
387                         continue;
388                 commit->object.flags |= REACHABLE;
389                 if (commit->date < oldest_have)
390                         continue;
391                 for (list = commit->parents; list; list = list->next) {
392                         struct commit *parent = list->item;
393                         if (!(parent->object.flags & REACHABLE))
394                                 insert_by_date(parent, &work);
395                 }
396         }
397         want->object.flags |= REACHABLE;
398         clear_commit_marks(want, REACHABLE);
399         free_commit_list(work);
400         return (want->object.flags & COMMON_KNOWN);
401 }
402
403 static int ok_to_give_up(void)
404 {
405         int i;
406
407         if (!have_obj.nr)
408                 return 0;
409
410         for (i = 0; i < want_obj.nr; i++) {
411                 struct object *want = want_obj.objects[i].item;
412
413                 if (want->flags & COMMON_KNOWN)
414                         continue;
415                 want = deref_tag(want, "a want line", 0);
416                 if (!want || want->type != OBJ_COMMIT) {
417                         /* no way to tell if this is reachable by
418                          * looking at the ancestry chain alone, so
419                          * leave a note to ourselves not to worry about
420                          * this object anymore.
421                          */
422                         want_obj.objects[i].item->flags |= COMMON_KNOWN;
423                         continue;
424                 }
425                 if (!reachable((struct commit *)want))
426                         return 0;
427         }
428         return 1;
429 }
430
431 static int get_common_commits(void)
432 {
433         static char line[1000];
434         unsigned char sha1[20];
435         char last_hex[41];
436
437         save_commit_buffer = 0;
438
439         for (;;) {
440                 int len = packet_read_line(0, line, sizeof(line));
441                 reset_timeout();
442
443                 if (!len) {
444                         if (have_obj.nr == 0 || multi_ack)
445                                 packet_write(1, "NAK\n");
446                         if (stateless_rpc)
447                                 exit(0);
448                         continue;
449                 }
450                 strip(line, len);
451                 if (!prefixcmp(line, "have ")) {
452                         switch (got_sha1(line+5, sha1)) {
453                         case -1: /* they have what we do not */
454                                 if (multi_ack && ok_to_give_up()) {
455                                         const char *hex = sha1_to_hex(sha1);
456                                         if (multi_ack == 2)
457                                                 packet_write(1, "ACK %s ready\n", hex);
458                                         else
459                                                 packet_write(1, "ACK %s continue\n", hex);
460                                 }
461                                 break;
462                         default:
463                                 memcpy(last_hex, sha1_to_hex(sha1), 41);
464                                 if (multi_ack == 2)
465                                         packet_write(1, "ACK %s common\n", last_hex);
466                                 else if (multi_ack)
467                                         packet_write(1, "ACK %s continue\n", last_hex);
468                                 else if (have_obj.nr == 1)
469                                         packet_write(1, "ACK %s\n", last_hex);
470                                 break;
471                         }
472                         continue;
473                 }
474                 if (!strcmp(line, "done")) {
475                         if (have_obj.nr > 0) {
476                                 if (multi_ack)
477                                         packet_write(1, "ACK %s\n", last_hex);
478                                 return 0;
479                         }
480                         packet_write(1, "NAK\n");
481                         return -1;
482                 }
483                 die("git upload-pack: expected SHA1 list, got '%s'", line);
484         }
485 }
486
487 static void receive_needs(void)
488 {
489         struct object_array shallows = {0, 0, NULL};
490         static char line[1000];
491         int len, depth = 0;
492
493         shallow_nr = 0;
494         if (debug_fd)
495                 write_str_in_full(debug_fd, "#S\n");
496         for (;;) {
497                 struct object *o;
498                 unsigned char sha1_buf[20];
499                 len = packet_read_line(0, line, sizeof(line));
500                 reset_timeout();
501                 if (!len)
502                         break;
503                 if (debug_fd)
504                         write_in_full(debug_fd, line, len);
505
506                 if (!prefixcmp(line, "shallow ")) {
507                         unsigned char sha1[20];
508                         struct object *object;
509                         if (get_sha1(line + 8, sha1))
510                                 die("invalid shallow line: %s", line);
511                         object = parse_object(sha1);
512                         if (!object)
513                                 die("did not find object for %s", line);
514                         object->flags |= CLIENT_SHALLOW;
515                         add_object_array(object, NULL, &shallows);
516                         continue;
517                 }
518                 if (!prefixcmp(line, "deepen ")) {
519                         char *end;
520                         depth = strtol(line + 7, &end, 0);
521                         if (end == line + 7 || depth <= 0)
522                                 die("Invalid deepen: %s", line);
523                         continue;
524                 }
525                 if (prefixcmp(line, "want ") ||
526                     get_sha1_hex(line+5, sha1_buf))
527                         die("git upload-pack: protocol error, "
528                             "expected to get sha, not '%s'", line);
529                 if (strstr(line+45, "multi_ack_detailed"))
530                         multi_ack = 2;
531                 else if (strstr(line+45, "multi_ack"))
532                         multi_ack = 1;
533                 if (strstr(line+45, "thin-pack"))
534                         use_thin_pack = 1;
535                 if (strstr(line+45, "ofs-delta"))
536                         use_ofs_delta = 1;
537                 if (strstr(line+45, "side-band-64k"))
538                         use_sideband = LARGE_PACKET_MAX;
539                 else if (strstr(line+45, "side-band"))
540                         use_sideband = DEFAULT_PACKET_MAX;
541                 if (strstr(line+45, "no-progress"))
542                         no_progress = 1;
543                 if (strstr(line+45, "include-tag"))
544                         use_include_tag = 1;
545
546                 /* We have sent all our refs already, and the other end
547                  * should have chosen out of them; otherwise they are
548                  * asking for nonsense.
549                  *
550                  * Hmph.  We may later want to allow "want" line that
551                  * asks for something like "master~10" (symbolic)...
552                  * would it make sense?  I don't know.
553                  */
554                 o = lookup_object(sha1_buf);
555                 if (!o || !(o->flags & OUR_REF))
556                         die("git upload-pack: not our ref %s", line+5);
557                 if (!(o->flags & WANTED)) {
558                         o->flags |= WANTED;
559                         add_object_array(o, NULL, &want_obj);
560                 }
561         }
562         if (debug_fd)
563                 write_str_in_full(debug_fd, "#E\n");
564
565         if (!use_sideband && daemon_mode)
566                 no_progress = 1;
567
568         if (depth == 0 && shallows.nr == 0)
569                 return;
570         if (depth > 0) {
571                 struct commit_list *result, *backup;
572                 int i;
573                 backup = result = get_shallow_commits(&want_obj, depth,
574                         SHALLOW, NOT_SHALLOW);
575                 while (result) {
576                         struct object *object = &result->item->object;
577                         if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
578                                 packet_write(1, "shallow %s",
579                                                 sha1_to_hex(object->sha1));
580                                 register_shallow(object->sha1);
581                                 shallow_nr++;
582                         }
583                         result = result->next;
584                 }
585                 free_commit_list(backup);
586                 for (i = 0; i < shallows.nr; i++) {
587                         struct object *object = shallows.objects[i].item;
588                         if (object->flags & NOT_SHALLOW) {
589                                 struct commit_list *parents;
590                                 packet_write(1, "unshallow %s",
591                                         sha1_to_hex(object->sha1));
592                                 object->flags &= ~CLIENT_SHALLOW;
593                                 /* make sure the real parents are parsed */
594                                 unregister_shallow(object->sha1);
595                                 object->parsed = 0;
596                                 if (parse_commit((struct commit *)object))
597                                         die("invalid commit");
598                                 parents = ((struct commit *)object)->parents;
599                                 while (parents) {
600                                         add_object_array(&parents->item->object,
601                                                         NULL, &want_obj);
602                                         parents = parents->next;
603                                 }
604                                 add_object_array(object, NULL, &extra_edge_obj);
605                         }
606                         /* make sure commit traversal conforms to client */
607                         register_shallow(object->sha1);
608                 }
609                 packet_flush(1);
610         } else
611                 if (shallows.nr > 0) {
612                         int i;
613                         for (i = 0; i < shallows.nr; i++)
614                                 register_shallow(shallows.objects[i].item->sha1);
615                 }
616
617         shallow_nr += shallows.nr;
618         free(shallows.objects);
619 }
620
621 static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
622 {
623         static const char *capabilities = "multi_ack thin-pack side-band"
624                 " side-band-64k ofs-delta shallow no-progress"
625                 " include-tag multi_ack_detailed";
626         struct object *o = parse_object(sha1);
627
628         if (!o)
629                 die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));
630
631         if (capabilities)
632                 packet_write(1, "%s %s%c%s\n", sha1_to_hex(sha1), refname,
633                         0, capabilities);
634         else
635                 packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
636         capabilities = NULL;
637         if (!(o->flags & OUR_REF)) {
638                 o->flags |= OUR_REF;
639                 nr_our_refs++;
640         }
641         if (o->type == OBJ_TAG) {
642                 o = deref_tag(o, refname, 0);
643                 if (o)
644                         packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
645         }
646         return 0;
647 }
648
649 static int mark_our_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
650 {
651         struct object *o = parse_object(sha1);
652         if (!o)
653                 die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));
654         if (!(o->flags & OUR_REF)) {
655                 o->flags |= OUR_REF;
656                 nr_our_refs++;
657         }
658         return 0;
659 }
660
661 static void upload_pack(void)
662 {
663         if (advertise_refs || !stateless_rpc) {
664                 reset_timeout();
665                 head_ref(send_ref, NULL);
666                 for_each_ref(send_ref, NULL);
667                 packet_flush(1);
668         } else {
669                 head_ref(mark_our_ref, NULL);
670                 for_each_ref(mark_our_ref, NULL);
671         }
672         if (advertise_refs)
673                 return;
674
675         receive_needs();
676         if (want_obj.nr) {
677                 get_common_commits();
678                 create_pack_file();
679         }
680 }
681
682 int main(int argc, char **argv)
683 {
684         char *dir;
685         int i;
686         int strict = 0;
687
688         git_extract_argv0_path(argv[0]);
689         read_replace_refs = 0;
690
691         for (i = 1; i < argc; i++) {
692                 char *arg = argv[i];
693
694                 if (arg[0] != '-')
695                         break;
696                 if (!strcmp(arg, "--advertise-refs")) {
697                         advertise_refs = 1;
698                         continue;
699                 }
700                 if (!strcmp(arg, "--stateless-rpc")) {
701                         stateless_rpc = 1;
702                         continue;
703                 }
704                 if (!strcmp(arg, "--strict")) {
705                         strict = 1;
706                         continue;
707                 }
708                 if (!prefixcmp(arg, "--timeout=")) {
709                         timeout = atoi(arg+10);
710                         daemon_mode = 1;
711                         continue;
712                 }
713                 if (!strcmp(arg, "--")) {
714                         i++;
715                         break;
716                 }
717         }
718
719         if (i != argc-1)
720                 usage(upload_pack_usage);
721
722         setup_path();
723
724         dir = argv[i];
725
726         if (!enter_repo(dir, strict))
727                 die("'%s' does not appear to be a git repository", dir);
728         if (is_repository_shallow())
729                 die("attempt to fetch/clone from a shallow repository");
730         if (getenv("GIT_DEBUG_SEND_PACK"))
731                 debug_fd = atoi(getenv("GIT_DEBUG_SEND_PACK"));
732         upload_pack();
733         return 0;
734 }