Start 1.7.4 cycle
[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 in, int out, void *user_data)
109 {
110         int i;
111         struct rev_info revs;
112
113         pack_pipe = xfdopen(out, "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         for (i = 0; i < want_obj.nr; i++) {
122                 struct object *o = want_obj.objects[i].item;
123                 /* why??? */
124                 o->flags &= ~UNINTERESTING;
125                 add_pending_object(&revs, o, NULL);
126         }
127         for (i = 0; i < have_obj.nr; i++) {
128                 struct object *o = have_obj.objects[i].item;
129                 o->flags |= UNINTERESTING;
130                 add_pending_object(&revs, o, NULL);
131         }
132         setup_revisions(0, NULL, &revs, NULL);
133         if (prepare_revision_walk(&revs))
134                 die("revision walk setup failed");
135         mark_edges_uninteresting(revs.commits, &revs, show_edge);
136         if (use_thin_pack)
137                 for (i = 0; i < extra_edge_obj.nr; i++)
138                         fprintf(pack_pipe, "-%s\n", sha1_to_hex(
139                                         extra_edge_obj.objects[i].item->sha1));
140         traverse_commit_list(&revs, show_commit, show_object, NULL);
141         fflush(pack_pipe);
142         fclose(pack_pipe);
143         return 0;
144 }
145
146 static void create_pack_file(void)
147 {
148         struct async rev_list;
149         struct child_process pack_objects;
150         int create_full_pack = (nr_our_refs == want_obj.nr && !have_obj.nr);
151         char data[8193], progress[128];
152         char abort_msg[] = "aborting due to possible repository "
153                 "corruption on the remote side.";
154         int buffered = -1;
155         ssize_t sz;
156         const char *argv[10];
157         int arg = 0;
158
159         if (shallow_nr) {
160                 memset(&rev_list, 0, sizeof(rev_list));
161                 rev_list.proc = do_rev_list;
162                 rev_list.out = -1;
163                 if (start_async(&rev_list))
164                         die("git upload-pack: unable to fork git-rev-list");
165                 argv[arg++] = "pack-objects";
166         } else {
167                 argv[arg++] = "pack-objects";
168                 argv[arg++] = "--revs";
169                 if (create_full_pack)
170                         argv[arg++] = "--all";
171                 else if (use_thin_pack)
172                         argv[arg++] = "--thin";
173         }
174
175         argv[arg++] = "--stdout";
176         if (!no_progress)
177                 argv[arg++] = "--progress";
178         if (use_ofs_delta)
179                 argv[arg++] = "--delta-base-offset";
180         if (use_include_tag)
181                 argv[arg++] = "--include-tag";
182         argv[arg++] = NULL;
183
184         memset(&pack_objects, 0, sizeof(pack_objects));
185         pack_objects.in = shallow_nr ? rev_list.out : -1;
186         pack_objects.out = -1;
187         pack_objects.err = -1;
188         pack_objects.git_cmd = 1;
189         pack_objects.argv = argv;
190
191         if (start_command(&pack_objects))
192                 die("git upload-pack: unable to fork git-pack-objects");
193
194         /* pass on revisions we (don't) want */
195         if (!shallow_nr) {
196                 FILE *pipe_fd = xfdopen(pack_objects.in, "w");
197                 if (!create_full_pack) {
198                         int i;
199                         for (i = 0; i < want_obj.nr; i++)
200                                 fprintf(pipe_fd, "%s\n", sha1_to_hex(want_obj.objects[i].item->sha1));
201                         fprintf(pipe_fd, "--not\n");
202                         for (i = 0; i < have_obj.nr; i++)
203                                 fprintf(pipe_fd, "%s\n", sha1_to_hex(have_obj.objects[i].item->sha1));
204                 }
205
206                 fprintf(pipe_fd, "\n");
207                 fflush(pipe_fd);
208                 fclose(pipe_fd);
209         }
210
211
212         /* We read from pack_objects.err to capture stderr output for
213          * progress bar, and pack_objects.out to capture the pack data.
214          */
215
216         while (1) {
217                 struct pollfd pfd[2];
218                 int pe, pu, pollsize;
219
220                 reset_timeout();
221
222                 pollsize = 0;
223                 pe = pu = -1;
224
225                 if (0 <= pack_objects.out) {
226                         pfd[pollsize].fd = pack_objects.out;
227                         pfd[pollsize].events = POLLIN;
228                         pu = pollsize;
229                         pollsize++;
230                 }
231                 if (0 <= pack_objects.err) {
232                         pfd[pollsize].fd = pack_objects.err;
233                         pfd[pollsize].events = POLLIN;
234                         pe = pollsize;
235                         pollsize++;
236                 }
237
238                 if (!pollsize)
239                         break;
240
241                 if (poll(pfd, pollsize, -1) < 0) {
242                         if (errno != EINTR) {
243                                 error("poll failed, resuming: %s",
244                                       strerror(errno));
245                                 sleep(1);
246                         }
247                         continue;
248                 }
249                 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
250                         /* Status ready; we ship that in the side-band
251                          * or dump to the standard error.
252                          */
253                         sz = xread(pack_objects.err, progress,
254                                   sizeof(progress));
255                         if (0 < sz)
256                                 send_client_data(2, progress, sz);
257                         else if (sz == 0) {
258                                 close(pack_objects.err);
259                                 pack_objects.err = -1;
260                         }
261                         else
262                                 goto fail;
263                         /* give priority to status messages */
264                         continue;
265                 }
266                 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
267                         /* Data ready; we keep the last byte to ourselves
268                          * in case we detect broken rev-list, so that we
269                          * can leave the stream corrupted.  This is
270                          * unfortunate -- unpack-objects would happily
271                          * accept a valid packdata with trailing garbage,
272                          * so appending garbage after we pass all the
273                          * pack data is not good enough to signal
274                          * breakage to downstream.
275                          */
276                         char *cp = data;
277                         ssize_t outsz = 0;
278                         if (0 <= buffered) {
279                                 *cp++ = buffered;
280                                 outsz++;
281                         }
282                         sz = xread(pack_objects.out, cp,
283                                   sizeof(data) - outsz);
284                         if (0 < sz)
285                                 ;
286                         else if (sz == 0) {
287                                 close(pack_objects.out);
288                                 pack_objects.out = -1;
289                         }
290                         else
291                                 goto fail;
292                         sz += outsz;
293                         if (1 < sz) {
294                                 buffered = data[sz-1] & 0xFF;
295                                 sz--;
296                         }
297                         else
298                                 buffered = -1;
299                         sz = send_client_data(1, data, sz);
300                         if (sz < 0)
301                                 goto fail;
302                 }
303         }
304
305         if (finish_command(&pack_objects)) {
306                 error("git upload-pack: git-pack-objects died with error.");
307                 goto fail;
308         }
309         if (shallow_nr && finish_async(&rev_list))
310                 goto fail;      /* error was already reported */
311
312         /* flush the data */
313         if (0 <= buffered) {
314                 data[0] = buffered;
315                 sz = send_client_data(1, data, 1);
316                 if (sz < 0)
317                         goto fail;
318                 fprintf(stderr, "flushed.\n");
319         }
320         if (use_sideband)
321                 packet_flush(1);
322         return;
323
324  fail:
325         send_client_data(3, abort_msg, sizeof(abort_msg));
326         die("git upload-pack: %s", abort_msg);
327 }
328
329 static int got_sha1(char *hex, unsigned char *sha1)
330 {
331         struct object *o;
332         int we_knew_they_have = 0;
333
334         if (get_sha1_hex(hex, sha1))
335                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
336         if (!has_sha1_file(sha1))
337                 return -1;
338
339         o = lookup_object(sha1);
340         if (!(o && o->parsed))
341                 o = parse_object(sha1);
342         if (!o)
343                 die("oops (%s)", sha1_to_hex(sha1));
344         if (o->type == OBJ_COMMIT) {
345                 struct commit_list *parents;
346                 struct commit *commit = (struct commit *)o;
347                 if (o->flags & THEY_HAVE)
348                         we_knew_they_have = 1;
349                 else
350                         o->flags |= THEY_HAVE;
351                 if (!oldest_have || (commit->date < oldest_have))
352                         oldest_have = commit->date;
353                 for (parents = commit->parents;
354                      parents;
355                      parents = parents->next)
356                         parents->item->object.flags |= THEY_HAVE;
357         }
358         if (!we_knew_they_have) {
359                 add_object_array(o, NULL, &have_obj);
360                 return 1;
361         }
362         return 0;
363 }
364
365 static int reachable(struct commit *want)
366 {
367         struct commit_list *work = NULL;
368
369         insert_by_date(want, &work);
370         while (work) {
371                 struct commit_list *list = work->next;
372                 struct commit *commit = work->item;
373                 free(work);
374                 work = list;
375
376                 if (commit->object.flags & THEY_HAVE) {
377                         want->object.flags |= COMMON_KNOWN;
378                         break;
379                 }
380                 if (!commit->object.parsed)
381                         parse_object(commit->object.sha1);
382                 if (commit->object.flags & REACHABLE)
383                         continue;
384                 commit->object.flags |= REACHABLE;
385                 if (commit->date < oldest_have)
386                         continue;
387                 for (list = commit->parents; list; list = list->next) {
388                         struct commit *parent = list->item;
389                         if (!(parent->object.flags & REACHABLE))
390                                 insert_by_date(parent, &work);
391                 }
392         }
393         want->object.flags |= REACHABLE;
394         clear_commit_marks(want, REACHABLE);
395         free_commit_list(work);
396         return (want->object.flags & COMMON_KNOWN);
397 }
398
399 static int ok_to_give_up(void)
400 {
401         int i;
402
403         if (!have_obj.nr)
404                 return 0;
405
406         for (i = 0; i < want_obj.nr; i++) {
407                 struct object *want = want_obj.objects[i].item;
408
409                 if (want->flags & COMMON_KNOWN)
410                         continue;
411                 want = deref_tag(want, "a want line", 0);
412                 if (!want || want->type != OBJ_COMMIT) {
413                         /* no way to tell if this is reachable by
414                          * looking at the ancestry chain alone, so
415                          * leave a note to ourselves not to worry about
416                          * this object anymore.
417                          */
418                         want_obj.objects[i].item->flags |= COMMON_KNOWN;
419                         continue;
420                 }
421                 if (!reachable((struct commit *)want))
422                         return 0;
423         }
424         return 1;
425 }
426
427 static int get_common_commits(void)
428 {
429         static char line[1000];
430         unsigned char sha1[20];
431         char last_hex[41];
432
433         save_commit_buffer = 0;
434
435         for (;;) {
436                 int len = packet_read_line(0, line, sizeof(line));
437                 reset_timeout();
438
439                 if (!len) {
440                         if (have_obj.nr == 0 || multi_ack)
441                                 packet_write(1, "NAK\n");
442                         if (stateless_rpc)
443                                 exit(0);
444                         continue;
445                 }
446                 strip(line, len);
447                 if (!prefixcmp(line, "have ")) {
448                         switch (got_sha1(line+5, sha1)) {
449                         case -1: /* they have what we do not */
450                                 if (multi_ack && ok_to_give_up()) {
451                                         const char *hex = sha1_to_hex(sha1);
452                                         if (multi_ack == 2)
453                                                 packet_write(1, "ACK %s ready\n", hex);
454                                         else
455                                                 packet_write(1, "ACK %s continue\n", hex);
456                                 }
457                                 break;
458                         default:
459                                 memcpy(last_hex, sha1_to_hex(sha1), 41);
460                                 if (multi_ack == 2)
461                                         packet_write(1, "ACK %s common\n", last_hex);
462                                 else if (multi_ack)
463                                         packet_write(1, "ACK %s continue\n", last_hex);
464                                 else if (have_obj.nr == 1)
465                                         packet_write(1, "ACK %s\n", last_hex);
466                                 break;
467                         }
468                         continue;
469                 }
470                 if (!strcmp(line, "done")) {
471                         if (have_obj.nr > 0) {
472                                 if (multi_ack)
473                                         packet_write(1, "ACK %s\n", last_hex);
474                                 return 0;
475                         }
476                         packet_write(1, "NAK\n");
477                         return -1;
478                 }
479                 die("git upload-pack: expected SHA1 list, got '%s'", line);
480         }
481 }
482
483 static void receive_needs(void)
484 {
485         struct object_array shallows = OBJECT_ARRAY_INIT;
486         static char line[1000];
487         int len, depth = 0;
488
489         shallow_nr = 0;
490         if (debug_fd)
491                 write_str_in_full(debug_fd, "#S\n");
492         for (;;) {
493                 struct object *o;
494                 unsigned char sha1_buf[20];
495                 len = packet_read_line(0, line, sizeof(line));
496                 reset_timeout();
497                 if (!len)
498                         break;
499                 if (debug_fd)
500                         write_in_full(debug_fd, line, len);
501
502                 if (!prefixcmp(line, "shallow ")) {
503                         unsigned char sha1[20];
504                         struct object *object;
505                         if (get_sha1(line + 8, sha1))
506                                 die("invalid shallow line: %s", line);
507                         object = parse_object(sha1);
508                         if (!object)
509                                 die("did not find object for %s", line);
510                         object->flags |= CLIENT_SHALLOW;
511                         add_object_array(object, NULL, &shallows);
512                         continue;
513                 }
514                 if (!prefixcmp(line, "deepen ")) {
515                         char *end;
516                         depth = strtol(line + 7, &end, 0);
517                         if (end == line + 7 || depth <= 0)
518                                 die("Invalid deepen: %s", line);
519                         continue;
520                 }
521                 if (prefixcmp(line, "want ") ||
522                     get_sha1_hex(line+5, sha1_buf))
523                         die("git upload-pack: protocol error, "
524                             "expected to get sha, not '%s'", line);
525                 if (strstr(line+45, "multi_ack_detailed"))
526                         multi_ack = 2;
527                 else if (strstr(line+45, "multi_ack"))
528                         multi_ack = 1;
529                 if (strstr(line+45, "thin-pack"))
530                         use_thin_pack = 1;
531                 if (strstr(line+45, "ofs-delta"))
532                         use_ofs_delta = 1;
533                 if (strstr(line+45, "side-band-64k"))
534                         use_sideband = LARGE_PACKET_MAX;
535                 else if (strstr(line+45, "side-band"))
536                         use_sideband = DEFAULT_PACKET_MAX;
537                 if (strstr(line+45, "no-progress"))
538                         no_progress = 1;
539                 if (strstr(line+45, "include-tag"))
540                         use_include_tag = 1;
541
542                 /* We have sent all our refs already, and the other end
543                  * should have chosen out of them; otherwise they are
544                  * asking for nonsense.
545                  *
546                  * Hmph.  We may later want to allow "want" line that
547                  * asks for something like "master~10" (symbolic)...
548                  * would it make sense?  I don't know.
549                  */
550                 o = lookup_object(sha1_buf);
551                 if (!o || !(o->flags & OUR_REF))
552                         die("git upload-pack: not our ref %s",
553                             sha1_to_hex(sha1_buf));
554                 if (!(o->flags & WANTED)) {
555                         o->flags |= WANTED;
556                         add_object_array(o, NULL, &want_obj);
557                 }
558         }
559         if (debug_fd)
560                 write_str_in_full(debug_fd, "#E\n");
561
562         if (!use_sideband && daemon_mode)
563                 no_progress = 1;
564
565         if (depth == 0 && shallows.nr == 0)
566                 return;
567         if (depth > 0) {
568                 struct commit_list *result, *backup;
569                 int i;
570                 backup = result = get_shallow_commits(&want_obj, depth,
571                         SHALLOW, NOT_SHALLOW);
572                 while (result) {
573                         struct object *object = &result->item->object;
574                         if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
575                                 packet_write(1, "shallow %s",
576                                                 sha1_to_hex(object->sha1));
577                                 register_shallow(object->sha1);
578                                 shallow_nr++;
579                         }
580                         result = result->next;
581                 }
582                 free_commit_list(backup);
583                 for (i = 0; i < shallows.nr; i++) {
584                         struct object *object = shallows.objects[i].item;
585                         if (object->flags & NOT_SHALLOW) {
586                                 struct commit_list *parents;
587                                 packet_write(1, "unshallow %s",
588                                         sha1_to_hex(object->sha1));
589                                 object->flags &= ~CLIENT_SHALLOW;
590                                 /* make sure the real parents are parsed */
591                                 unregister_shallow(object->sha1);
592                                 object->parsed = 0;
593                                 if (parse_commit((struct commit *)object))
594                                         die("invalid commit");
595                                 parents = ((struct commit *)object)->parents;
596                                 while (parents) {
597                                         add_object_array(&parents->item->object,
598                                                         NULL, &want_obj);
599                                         parents = parents->next;
600                                 }
601                                 add_object_array(object, NULL, &extra_edge_obj);
602                         }
603                         /* make sure commit traversal conforms to client */
604                         register_shallow(object->sha1);
605                 }
606                 packet_flush(1);
607         } else
608                 if (shallows.nr > 0) {
609                         int i;
610                         for (i = 0; i < shallows.nr; i++)
611                                 register_shallow(shallows.objects[i].item->sha1);
612                 }
613
614         shallow_nr += shallows.nr;
615         free(shallows.objects);
616 }
617
618 static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
619 {
620         static const char *capabilities = "multi_ack thin-pack side-band"
621                 " side-band-64k ofs-delta shallow no-progress"
622                 " include-tag multi_ack_detailed";
623         struct object *o = parse_object(sha1);
624
625         if (!o)
626                 die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));
627
628         if (capabilities)
629                 packet_write(1, "%s %s%c%s\n", sha1_to_hex(sha1), refname,
630                         0, capabilities);
631         else
632                 packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
633         capabilities = NULL;
634         if (!(o->flags & OUR_REF)) {
635                 o->flags |= OUR_REF;
636                 nr_our_refs++;
637         }
638         if (o->type == OBJ_TAG) {
639                 o = deref_tag(o, refname, 0);
640                 if (o)
641                         packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
642         }
643         return 0;
644 }
645
646 static int mark_our_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
647 {
648         struct object *o = parse_object(sha1);
649         if (!o)
650                 die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));
651         if (!(o->flags & OUR_REF)) {
652                 o->flags |= OUR_REF;
653                 nr_our_refs++;
654         }
655         return 0;
656 }
657
658 static void upload_pack(void)
659 {
660         if (advertise_refs || !stateless_rpc) {
661                 reset_timeout();
662                 head_ref(send_ref, NULL);
663                 for_each_ref(send_ref, NULL);
664                 packet_flush(1);
665         } else {
666                 head_ref(mark_our_ref, NULL);
667                 for_each_ref(mark_our_ref, NULL);
668         }
669         if (advertise_refs)
670                 return;
671
672         receive_needs();
673         if (want_obj.nr) {
674                 get_common_commits();
675                 create_pack_file();
676         }
677 }
678
679 int main(int argc, char **argv)
680 {
681         char *dir;
682         int i;
683         int strict = 0;
684
685         git_extract_argv0_path(argv[0]);
686         read_replace_refs = 0;
687
688         for (i = 1; i < argc; i++) {
689                 char *arg = argv[i];
690
691                 if (arg[0] != '-')
692                         break;
693                 if (!strcmp(arg, "--advertise-refs")) {
694                         advertise_refs = 1;
695                         continue;
696                 }
697                 if (!strcmp(arg, "--stateless-rpc")) {
698                         stateless_rpc = 1;
699                         continue;
700                 }
701                 if (!strcmp(arg, "--strict")) {
702                         strict = 1;
703                         continue;
704                 }
705                 if (!prefixcmp(arg, "--timeout=")) {
706                         timeout = atoi(arg+10);
707                         daemon_mode = 1;
708                         continue;
709                 }
710                 if (!strcmp(arg, "--")) {
711                         i++;
712                         break;
713                 }
714         }
715
716         if (i != argc-1)
717                 usage(upload_pack_usage);
718
719         setup_path();
720
721         dir = argv[i];
722
723         if (!enter_repo(dir, strict))
724                 die("'%s' does not appear to be a git repository", dir);
725         if (is_repository_shallow())
726                 die("attempt to fetch/clone from a shallow repository");
727         if (getenv("GIT_DEBUG_SEND_PACK"))
728                 debug_fd = atoi(getenv("GIT_DEBUG_SEND_PACK"));
729         upload_pack();
730         return 0;
731 }