builtin-fetch-pack.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "pkt-line.h"
   4 #include "commit.h"
   5 #include "tag.h"
   6 #include "exec_cmd.h"
   7 #include "pack.h"
   8 #include "sideband.h"
   9 #include "fetch-pack.h"
  10 #include "remote.h"
  11 #include "run-command.h"
  12
  13 static int transfer_unpack_limit = -1;
  14 static int fetch_unpack_limit = -1;
  15 static int unpack_limit = 100;
  16 static struct fetch_pack_args args = {
  17         /* .uploadpack = */ "git-upload-pack",
  18 };
  19
  20 static const char fetch_pack_usage[] =
  21 "git fetch-pack [--all] [--quiet|-q] [--keep|-k] [--thin] [--include-tag] [--upload-pack=<git-upload-pack>] [--depth=<n>] [--no-progress] [-v] [<host>:]<directory> [<refs>...]";
  22
  23 #define COMPLETE        (1U << 0)
  24 #define COMMON          (1U << 1)
  25 #define COMMON_REF      (1U << 2)
  26 #define SEEN            (1U << 3)
  27 #define POPPED          (1U << 4)
  28
  29 static int marked;
  30
  31 /*
  32  * After sending this many "have"s if we do not get any new ACK , we
  33  * give up traversing our history.
  34  */
  35 #define MAX_IN_VAIN 256
  36
  37 static struct commit_list *rev_list;
  38 static int non_common_revs, multi_ack, use_sideband;
  39
  40 static void rev_list_push(struct commit *commit, int mark)
  41 {
  42         if (!(commit->object.flags & mark)) {
  43                 commit->object.flags |= mark;
  44
  45                 if (!(commit->object.parsed))
  46                         if (parse_commit(commit))
  47                                 return;
  48
  49                 insert_by_date(commit, &rev_list);
  50
  51                 if (!(commit->object.flags & COMMON))
  52                         non_common_revs++;
  53         }
  54 }
  55
  56 static int rev_list_insert_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
  57 {
  58         struct object *o = deref_tag(parse_object(sha1), path, 0);
  59
  60         if (o && o->type == OBJ_COMMIT)
  61                 rev_list_push((struct commit *)o, SEEN);
  62
  63         return 0;
  64 }
  65
  66 static int clear_marks(const char *path, const unsigned char *sha1, int flag, void *cb_data)
  67 {
  68         struct object *o = deref_tag(parse_object(sha1), path, 0);
  69
  70         if (o && o->type == OBJ_COMMIT)
  71                 clear_commit_marks((struct commit *)o,
  72                                    COMMON | COMMON_REF | SEEN | POPPED);
  73         return 0;
  74 }
  75
  76 /*
  77    This function marks a rev and its ancestors as common.
  78    In some cases, it is desirable to mark only the ancestors (for example
  79    when only the server does not yet know that they are common).
  80 */
  81
  82 static void mark_common(struct commit *commit,
  83                 int ancestors_only, int dont_parse)
  84 {
  85         if (commit != NULL && !(commit->object.flags & COMMON)) {
  86                 struct object *o = (struct object *)commit;
  87
  88                 if (!ancestors_only)
  89                         o->flags |= COMMON;
  90
  91                 if (!(o->flags & SEEN))
  92                         rev_list_push(commit, SEEN);
  93                 else {
  94                         struct commit_list *parents;
  95
  96                         if (!ancestors_only && !(o->flags & POPPED))
  97                                 non_common_revs--;
  98                         if (!o->parsed && !dont_parse)
  99                                 if (parse_commit(commit))
 100                                         return;
 101
 102                         for (parents = commit->parents;
 103                                         parents;
 104                                         parents = parents->next)
 105                                 mark_common(parents->item, 0, dont_parse);
 106                 }
 107         }
 108 }
 109
 110 /*
 111   Get the next rev to send, ignoring the common.
 112 */
 113
 114 static const unsigned char* get_rev(void)
 115 {
 116         struct commit *commit = NULL;
 117
 118         while (commit == NULL) {
 119                 unsigned int mark;
 120                 struct commit_list *parents;
 121
 122                 if (rev_list == NULL || non_common_revs == 0)
 123                         return NULL;
 124
 125                 commit = rev_list->item;
 126                 if (!commit->object.parsed)
 127                         parse_commit(commit);
 128                 parents = commit->parents;
 129
 130                 commit->object.flags |= POPPED;
 131                 if (!(commit->object.flags & COMMON))
 132                         non_common_revs--;
 133
 134                 if (commit->object.flags & COMMON) {
 135                         /* do not send "have", and ignore ancestors */
 136                         commit = NULL;
 137                         mark = COMMON | SEEN;
 138                 } else if (commit->object.flags & COMMON_REF)
 139                         /* send "have", and ignore ancestors */
 140                         mark = COMMON | SEEN;
 141                 else
 142                         /* send "have", also for its ancestors */
 143                         mark = SEEN;
 144
 145                 while (parents) {
 146                         if (!(parents->item->object.flags & SEEN))
 147                                 rev_list_push(parents->item, mark);
 148                         if (mark & COMMON)
 149                                 mark_common(parents->item, 1, 0);
 150                         parents = parents->next;
 151                 }
 152
 153                 rev_list = rev_list->next;
 154         }
 155
 156         return commit->object.sha1;
 157 }
 158
 159 static int find_common(int fd[2], unsigned char *result_sha1,
 160                        struct ref *refs)
 161 {
 162         int fetching;
 163         int count = 0, flushes = 0, retval;
 164         const unsigned char *sha1;
 165         unsigned in_vain = 0;
 166         int got_continue = 0;
 167
 168         if (marked)
 169                 for_each_ref(clear_marks, NULL);
 170         marked = 1;
 171
 172         for_each_ref(rev_list_insert_ref, NULL);
 173
 174         fetching = 0;
 175         for ( ; refs ; refs = refs->next) {
 176                 unsigned char *remote = refs->old_sha1;
 177                 struct object *o;
 178
 179                 /*
 180                  * If that object is complete (i.e. it is an ancestor of a
 181                  * local ref), we tell them we have it but do not have to
 182                  * tell them about its ancestors, which they already know
 183                  * about.
 184                  *
 185                  * We use lookup_object here because we are only
 186                  * interested in the case we *know* the object is
 187                  * reachable and we have already scanned it.
 188                  */
 189                 if (((o = lookup_object(remote)) != NULL) &&
 190                                 (o->flags & COMPLETE)) {
 191                         continue;
 192                 }
 193
 194                 if (!fetching)
 195                         packet_write(fd[1], "want %s%s%s%s%s%s%s%s\n",
 196                                      sha1_to_hex(remote),
 197                                      (multi_ack ? " multi_ack" : ""),
 198                                      (use_sideband == 2 ? " side-band-64k" : ""),
 199                                      (use_sideband == 1 ? " side-band" : ""),
 200                                      (args.use_thin_pack ? " thin-pack" : ""),
 201                                      (args.no_progress ? " no-progress" : ""),
 202                                      (args.include_tag ? " include-tag" : ""),
 203                                      " ofs-delta");
 204                 else
 205                         packet_write(fd[1], "want %s\n", sha1_to_hex(remote));
 206                 fetching++;
 207         }
 208         if (is_repository_shallow())
 209                 write_shallow_commits(fd[1], 1);
 210         if (args.depth > 0)
 211                 packet_write(fd[1], "deepen %d", args.depth);
 212         packet_flush(fd[1]);
 213         if (!fetching)
 214                 return 1;
 215
 216         if (args.depth > 0) {
 217                 char line[1024];
 218                 unsigned char sha1[20];
 219
 220                 while (packet_read_line(fd[0], line, sizeof(line))) {
 221                         if (!prefixcmp(line, "shallow ")) {
 222                                 if (get_sha1_hex(line + 8, sha1))
 223                                         die("invalid shallow line: %s", line);
 224                                 register_shallow(sha1);
 225                                 continue;
 226                         }
 227                         if (!prefixcmp(line, "unshallow ")) {
 228                                 if (get_sha1_hex(line + 10, sha1))
 229                                         die("invalid unshallow line: %s", line);
 230                                 if (!lookup_object(sha1))
 231                                         die("object not found: %s", line);
 232                                 /* make sure that it is parsed as shallow */
 233                                 if (!parse_object(sha1))
 234                                         die("error in object: %s", line);
 235                                 if (unregister_shallow(sha1))
 236                                         die("no shallow found: %s", line);
 237                                 continue;
 238                         }
 239                         die("expected shallow/unshallow, got %s", line);
 240                 }
 241         }
 242
 243         flushes = 0;
 244         retval = -1;
 245         while ((sha1 = get_rev())) {
 246                 packet_write(fd[1], "have %s\n", sha1_to_hex(sha1));
 247                 if (args.verbose)
 248                         fprintf(stderr, "have %s\n", sha1_to_hex(sha1));
 249                 in_vain++;
 250                 if (!(31 & ++count)) {
 251                         int ack;
 252
 253                         packet_flush(fd[1]);
 254                         flushes++;
 255
 256                         /*
 257                          * We keep one window "ahead" of the other side, and
 258                          * will wait for an ACK only on the next one
 259                          */
 260                         if (count == 32)
 261                                 continue;
 262
 263                         do {
 264                                 ack = get_ack(fd[0], result_sha1);
 265                                 if (args.verbose && ack)
 266                                         fprintf(stderr, "got ack %d %s\n", ack,
 267                                                         sha1_to_hex(result_sha1));
 268                                 if (ack == 1) {
 269                                         flushes = 0;
 270                                         multi_ack = 0;
 271                                         retval = 0;
 272                                         goto done;
 273                                 } else if (ack == 2) {
 274                                         struct commit *commit =
 275                                                 lookup_commit(result_sha1);
 276                                         mark_common(commit, 0, 1);
 277                                         retval = 0;
 278                                         in_vain = 0;
 279                                         got_continue = 1;
 280                                 }
 281                         } while (ack);
 282                         flushes--;
 283                         if (got_continue && MAX_IN_VAIN < in_vain) {
 284                                 if (args.verbose)
 285                                         fprintf(stderr, "giving up\n");
 286                                 break; /* give up */
 287                         }
 288                 }
 289         }
 290 done:
 291         packet_write(fd[1], "done\n");
 292         if (args.verbose)
 293                 fprintf(stderr, "done\n");
 294         if (retval != 0) {
 295                 multi_ack = 0;
 296                 flushes++;
 297         }
 298         while (flushes || multi_ack) {
 299                 int ack = get_ack(fd[0], result_sha1);
 300                 if (ack) {
 301                         if (args.verbose)
 302                                 fprintf(stderr, "got ack (%d) %s\n", ack,
 303                                         sha1_to_hex(result_sha1));
 304                         if (ack == 1)
 305                                 return 0;
 306                         multi_ack = 1;
 307                         continue;
 308                 }
 309                 flushes--;
 310         }
 311         /* it is no error to fetch into a completely empty repo */
 312         return count ? retval : 0;
 313 }
 314
 315 static struct commit_list *complete;
 316
 317 static int mark_complete(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 318 {
 319         struct object *o = parse_object(sha1);
 320
 321         while (o && o->type == OBJ_TAG) {
 322                 struct tag *t = (struct tag *) o;
 323                 if (!t->tagged)
 324                         break; /* broken repository */
 325                 o->flags |= COMPLETE;
 326                 o = parse_object(t->tagged->sha1);
 327         }
 328         if (o && o->type == OBJ_COMMIT) {
 329                 struct commit *commit = (struct commit *)o;
 330                 commit->object.flags |= COMPLETE;
 331                 insert_by_date(commit, &complete);
 332         }
 333         return 0;
 334 }
 335
 336 static void mark_recent_complete_commits(unsigned long cutoff)
 337 {
 338         while (complete && cutoff <= complete->item->date) {
 339                 if (args.verbose)
 340                         fprintf(stderr, "Marking %s as complete\n",
 341                                 sha1_to_hex(complete->item->object.sha1));
 342                 pop_most_recent_commit(&complete, COMPLETE);
 343         }
 344 }
 345
 346 static void filter_refs(struct ref **refs, int nr_match, char **match)
 347 {
 348         struct ref **return_refs;
 349         struct ref *newlist = NULL;
 350         struct ref **newtail = &newlist;
 351         struct ref *ref, *next;
 352         struct ref *fastarray[32];
 353
 354         if (nr_match && !args.fetch_all) {
 355                 if (ARRAY_SIZE(fastarray) < nr_match)
 356                         return_refs = xcalloc(nr_match, sizeof(struct ref *));
 357                 else {
 358                         return_refs = fastarray;
 359                         memset(return_refs, 0, sizeof(struct ref *) * nr_match);
 360                 }
 361         }
 362         else
 363                 return_refs = NULL;
 364
 365         for (ref = *refs; ref; ref = next) {
 366                 next = ref->next;
 367                 if (!memcmp(ref->name, "refs/", 5) &&
 368                     check_ref_format(ref->name + 5))
 369                         ; /* trash */
 370                 else if (args.fetch_all &&
 371                          (!args.depth || prefixcmp(ref->name, "refs/tags/") )) {
 372                         *newtail = ref;
 373                         ref->next = NULL;
 374                         newtail = &ref->next;
 375                         continue;
 376                 }
 377                 else {
 378                         int order = path_match(ref->name, nr_match, match);
 379                         if (order) {
 380                                 return_refs[order-1] = ref;
 381                                 continue; /* we will link it later */
 382                         }
 383                 }
 384                 free(ref);
 385         }
 386
 387         if (!args.fetch_all) {
 388                 int i;
 389                 for (i = 0; i < nr_match; i++) {
 390                         ref = return_refs[i];
 391                         if (ref) {
 392                                 *newtail = ref;
 393                                 ref->next = NULL;
 394                                 newtail = &ref->next;
 395                         }
 396                 }
 397                 if (return_refs != fastarray)
 398                         free(return_refs);
 399         }
 400         *refs = newlist;
 401 }
 402
 403 static int everything_local(struct ref **refs, int nr_match, char **match)
 404 {
 405         struct ref *ref;
 406         int retval;
 407         unsigned long cutoff = 0;
 408
 409         save_commit_buffer = 0;
 410
 411         for (ref = *refs; ref; ref = ref->next) {
 412                 struct object *o;
 413
 414                 o = parse_object(ref->old_sha1);
 415                 if (!o)
 416                         continue;
 417
 418                 /* We already have it -- which may mean that we were
 419                  * in sync with the other side at some time after
 420                  * that (it is OK if we guess wrong here).
 421                  */
 422                 if (o->type == OBJ_COMMIT) {
 423                         struct commit *commit = (struct commit *)o;
 424                         if (!cutoff || cutoff < commit->date)
 425                                 cutoff = commit->date;
 426                 }
 427         }
 428
 429         if (!args.depth) {
 430                 for_each_ref(mark_complete, NULL);
 431                 if (cutoff)
 432                         mark_recent_complete_commits(cutoff);
 433         }
 434
 435         /*
 436          * Mark all complete remote refs as common refs.
 437          * Don't mark them common yet; the server has to be told so first.
 438          */
 439         for (ref = *refs; ref; ref = ref->next) {
 440                 struct object *o = deref_tag(lookup_object(ref->old_sha1),
 441                                              NULL, 0);
 442
 443                 if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 444                         continue;
 445
 446                 if (!(o->flags & SEEN)) {
 447                         rev_list_push((struct commit *)o, COMMON_REF | SEEN);
 448
 449                         mark_common((struct commit *)o, 1, 1);
 450                 }
 451         }
 452
 453         filter_refs(refs, nr_match, match);
 454
 455         for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 456                 const unsigned char *remote = ref->old_sha1;
 457                 unsigned char local[20];
 458                 struct object *o;
 459
 460                 o = lookup_object(remote);
 461                 if (!o || !(o->flags & COMPLETE)) {
 462                         retval = 0;
 463                         if (!args.verbose)
 464                                 continue;
 465                         fprintf(stderr,
 466                                 "want %s (%s)\n", sha1_to_hex(remote),
 467                                 ref->name);
 468                         continue;
 469                 }
 470
 471                 hashcpy(ref->new_sha1, local);
 472                 if (!args.verbose)
 473                         continue;
 474                 fprintf(stderr,
 475                         "already have %s (%s)\n", sha1_to_hex(remote),
 476                         ref->name);
 477         }
 478         return retval;
 479 }
 480
 481 static int sideband_demux(int fd, void *data)
 482 {
 483         int *xd = data;
 484
 485         return recv_sideband("fetch-pack", xd[0], fd);
 486 }
 487
 488 static int get_pack(int xd[2], char **pack_lockfile)
 489 {
 490         struct async demux;
 491         const char *argv[20];
 492         char keep_arg[256];
 493         char hdr_arg[256];
 494         const char **av;
 495         int do_keep = args.keep_pack;
 496         struct child_process cmd;
 497
 498         memset(&demux, 0, sizeof(demux));
 499         if (use_sideband) {
 500                 /* xd[] is talking with upload-pack; subprocess reads from
 501                  * xd[0], spits out band#2 to stderr, and feeds us band#1
 502                  * through demux->out.
 503                  */
 504                 demux.proc = sideband_demux;
 505                 demux.data = xd;
 506                 if (start_async(&demux))
 507                         die("fetch-pack: unable to fork off sideband"
 508                             " demultiplexer");
 509         }
 510         else
 511                 demux.out = xd[0];
 512
 513         memset(&cmd, 0, sizeof(cmd));
 514         cmd.argv = argv;
 515         av = argv;
 516         *hdr_arg = 0;
 517         if (!args.keep_pack && unpack_limit) {
 518                 struct pack_header header;
 519
 520                 if (read_pack_header(demux.out, &header))
 521                         die("protocol error: bad pack header");
 522                 snprintf(hdr_arg, sizeof(hdr_arg),
 523                          "--pack_header=%"PRIu32",%"PRIu32,
 524                          ntohl(header.hdr_version), ntohl(header.hdr_entries));
 525                 if (ntohl(header.hdr_entries) < unpack_limit)
 526                         do_keep = 0;
 527                 else
 528                         do_keep = 1;
 529         }
 530
 531         if (do_keep) {
 532                 if (pack_lockfile)
 533                         cmd.out = -1;
 534                 *av++ = "index-pack";
 535                 *av++ = "--stdin";
 536                 if (!args.quiet && !args.no_progress)
 537                         *av++ = "-v";
 538                 if (args.use_thin_pack)
 539                         *av++ = "--fix-thin";
 540                 if (args.lock_pack || unpack_limit) {
 541                         int s = sprintf(keep_arg,
 542                                         "--keep=fetch-pack %"PRIuMAX " on ", (uintmax_t) getpid());
 543                         if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
 544                                 strcpy(keep_arg + s, "localhost");
 545                         *av++ = keep_arg;
 546                 }
 547         }
 548         else {
 549                 *av++ = "unpack-objects";
 550                 if (args.quiet)
 551                         *av++ = "-q";
 552         }
 553         if (*hdr_arg)
 554                 *av++ = hdr_arg;
 555         *av++ = NULL;
 556
 557         cmd.in = demux.out;
 558         cmd.git_cmd = 1;
 559         if (start_command(&cmd))
 560                 die("fetch-pack: unable to fork off %s", argv[0]);
 561         if (do_keep && pack_lockfile) {
 562                 *pack_lockfile = index_pack_lockfile(cmd.out);
 563                 close(cmd.out);
 564         }
 565
 566         if (finish_command(&cmd))
 567                 die("%s failed", argv[0]);
 568         if (use_sideband && finish_async(&demux))
 569                 die("error in sideband demultiplexer");
 570         return 0;
 571 }
 572
 573 static struct ref *do_fetch_pack(int fd[2],
 574                 const struct ref *orig_ref,
 575                 int nr_match,
 576                 char **match,
 577                 char **pack_lockfile)
 578 {
 579         struct ref *ref = copy_ref_list(orig_ref);
 580         unsigned char sha1[20];
 581
 582         if (is_repository_shallow() && !server_supports("shallow"))
 583                 die("Server does not support shallow clients");
 584         if (server_supports("multi_ack")) {
 585                 if (args.verbose)
 586                         fprintf(stderr, "Server supports multi_ack\n");
 587                 multi_ack = 1;
 588         }
 589         if (server_supports("side-band-64k")) {
 590                 if (args.verbose)
 591                         fprintf(stderr, "Server supports side-band-64k\n");
 592                 use_sideband = 2;
 593         }
 594         else if (server_supports("side-band")) {
 595                 if (args.verbose)
 596                         fprintf(stderr, "Server supports side-band\n");
 597                 use_sideband = 1;
 598         }
 599         if (everything_local(&ref, nr_match, match)) {
 600                 packet_flush(fd[1]);
 601                 goto all_done;
 602         }
 603         if (find_common(fd, sha1, ref) < 0)
 604                 if (!args.keep_pack)
 605                         /* When cloning, it is not unusual to have
 606                          * no common commit.
 607                          */
 608                         fprintf(stderr, "warning: no common commits\n");
 609
 610         if (get_pack(fd, pack_lockfile))
 611                 die("git fetch-pack: fetch failed.");
 612
 613  all_done:
 614         return ref;
 615 }
 616
 617 static int remove_duplicates(int nr_heads, char **heads)
 618 {
 619         int src, dst;
 620
 621         for (src = dst = 0; src < nr_heads; src++) {
 622                 /* If heads[src] is different from any of
 623                  * heads[0..dst], push it in.
 624                  */
 625                 int i;
 626                 for (i = 0; i < dst; i++) {
 627                         if (!strcmp(heads[i], heads[src]))
 628                                 break;
 629                 }
 630                 if (i < dst)
 631                         continue;
 632                 if (src != dst)
 633                         heads[dst] = heads[src];
 634                 dst++;
 635         }
 636         return dst;
 637 }
 638
 639 static int fetch_pack_config(const char *var, const char *value, void *cb)
 640 {
 641         if (strcmp(var, "fetch.unpacklimit") == 0) {
 642                 fetch_unpack_limit = git_config_int(var, value);
 643                 return 0;
 644         }
 645
 646         if (strcmp(var, "transfer.unpacklimit") == 0) {
 647                 transfer_unpack_limit = git_config_int(var, value);
 648                 return 0;
 649         }
 650
 651         return git_default_config(var, value, cb);
 652 }
 653
 654 static struct lock_file lock;
 655
 656 static void fetch_pack_setup(void)
 657 {
 658         static int did_setup;
 659         if (did_setup)
 660                 return;
 661         git_config(fetch_pack_config, NULL);
 662         if (0 <= transfer_unpack_limit)
 663                 unpack_limit = transfer_unpack_limit;
 664         else if (0 <= fetch_unpack_limit)
 665                 unpack_limit = fetch_unpack_limit;
 666         did_setup = 1;
 667 }
 668
 669 int cmd_fetch_pack(int argc, const char **argv, const char *prefix)
 670 {
 671         int i, ret, nr_heads;
 672         struct ref *ref = NULL;
 673         char *dest = NULL, **heads;
 674         int fd[2];
 675         struct child_process *conn;
 676
 677         nr_heads = 0;
 678         heads = NULL;
 679         for (i = 1; i < argc; i++) {
 680                 const char *arg = argv[i];
 681
 682                 if (*arg == '-') {
 683                         if (!prefixcmp(arg, "--upload-pack=")) {
 684                                 args.uploadpack = arg + 14;
 685                                 continue;
 686                         }
 687                         if (!prefixcmp(arg, "--exec=")) {
 688                                 args.uploadpack = arg + 7;
 689                                 continue;
 690                         }
 691                         if (!strcmp("--quiet", arg) || !strcmp("-q", arg)) {
 692                                 args.quiet = 1;
 693                                 continue;
 694                         }
 695                         if (!strcmp("--keep", arg) || !strcmp("-k", arg)) {
 696                                 args.lock_pack = args.keep_pack;
 697                                 args.keep_pack = 1;
 698                                 continue;
 699                         }
 700                         if (!strcmp("--thin", arg)) {
 701                                 args.use_thin_pack = 1;
 702                                 continue;
 703                         }
 704                         if (!strcmp("--include-tag", arg)) {
 705                                 args.include_tag = 1;
 706                                 continue;
 707                         }
 708                         if (!strcmp("--all", arg)) {
 709                                 args.fetch_all = 1;
 710                                 continue;
 711                         }
 712                         if (!strcmp("-v", arg)) {
 713                                 args.verbose = 1;
 714                                 continue;
 715                         }
 716                         if (!prefixcmp(arg, "--depth=")) {
 717                                 args.depth = strtol(arg + 8, NULL, 0);
 718                                 continue;
 719                         }
 720                         if (!strcmp("--no-progress", arg)) {
 721                                 args.no_progress = 1;
 722                                 continue;
 723                         }
 724                         usage(fetch_pack_usage);
 725                 }
 726                 dest = (char *)arg;
 727                 heads = (char **)(argv + i + 1);
 728                 nr_heads = argc - i - 1;
 729                 break;
 730         }
 731         if (!dest)
 732                 usage(fetch_pack_usage);
 733
 734         conn = git_connect(fd, (char *)dest, args.uploadpack,
 735                            args.verbose ? CONNECT_VERBOSE : 0);
 736         if (conn) {
 737                 get_remote_heads(fd[0], &ref, 0, NULL, 0, NULL);
 738
 739                 ref = fetch_pack(&args, fd, conn, ref, dest, nr_heads, heads, NULL);
 740                 close(fd[0]);
 741                 close(fd[1]);
 742                 if (finish_connect(conn))
 743                         ref = NULL;
 744         } else {
 745                 ref = NULL;
 746         }
 747         ret = !ref;
 748
 749         if (!ret && nr_heads) {
 750                 /* If the heads to pull were given, we should have
 751                  * consumed all of them by matching the remote.
 752                  * Otherwise, 'git fetch remote no-such-ref' would
 753                  * silently succeed without issuing an error.
 754                  */
 755                 for (i = 0; i < nr_heads; i++)
 756                         if (heads[i] && heads[i][0]) {
 757                                 error("no such remote ref %s", heads[i]);
 758                                 ret = 1;
 759                         }
 760         }
 761         while (ref) {
 762                 printf("%s %s\n",
 763                        sha1_to_hex(ref->old_sha1), ref->name);
 764                 ref = ref->next;
 765         }
 766
 767         return ret;
 768 }
 769
 770 struct ref *fetch_pack(struct fetch_pack_args *my_args,
 771                        int fd[], struct child_process *conn,
 772                        const struct ref *ref,
 773                 const char *dest,
 774                 int nr_heads,
 775                 char **heads,
 776                 char **pack_lockfile)
 777 {
 778         struct stat st;
 779         struct ref *ref_cpy;
 780
 781         fetch_pack_setup();
 782         if (&args != my_args)
 783                 memcpy(&args, my_args, sizeof(args));
 784         if (args.depth > 0) {
 785                 if (stat(git_path("shallow"), &st))
 786                         st.st_mtime = 0;
 787         }
 788
 789         if (heads && nr_heads)
 790                 nr_heads = remove_duplicates(nr_heads, heads);
 791         if (!ref) {
 792                 packet_flush(fd[1]);
 793                 die("no matching remote head");
 794         }
 795         ref_cpy = do_fetch_pack(fd, ref, nr_heads, heads, pack_lockfile);
 796
 797         if (args.depth > 0) {
 798                 struct cache_time mtime;
 799                 char *shallow = git_path("shallow");
 800                 int fd;
 801
 802                 mtime.sec = st.st_mtime;
 803                 mtime.nsec = ST_MTIME_NSEC(st);
 804                 if (stat(shallow, &st)) {
 805                         if (mtime.sec)
 806                                 die("shallow file was removed during fetch");
 807                 } else if (st.st_mtime != mtime.sec
 808 #ifdef USE_NSEC
 809                                 || ST_MTIME_NSEC(st) != mtime.nsec
 810 #endif
 811                           )
 812                         die("shallow file was changed during fetch");
 813
 814                 fd = hold_lock_file_for_update(&lock, shallow,
 815                                                LOCK_DIE_ON_ERROR);
 816                 if (!write_shallow_commits(fd, 0)) {
 817                         unlink(shallow);
 818                         rollback_lock_file(&lock);
 819                 } else {
 820                         commit_lock_file(&lock);
 821                 }
 822         }
 823
 824         reprepare_packed_git();
 825         return ref_cpy;
 826 }