git.oblomov.eu Git - git/blob - builtin/fetch-pack.c

   1 #include "builtin.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 #include "transport.h"
  13 #include "version.h"
  14
  15 static int transfer_unpack_limit = -1;
  16 static int fetch_unpack_limit = -1;
  17 static int unpack_limit = 100;
  18 static int prefer_ofs_delta = 1;
  19 static int no_done;
  20 static int fetch_fsck_objects = -1;
  21 static int transfer_fsck_objects = -1;
  22 static int agent_supported;
  23 static struct fetch_pack_args args = {
  24         /* .uploadpack = */ "git-upload-pack",
  25 };
  26
  27 static const char fetch_pack_usage[] =
  28 "git fetch-pack [--all] [--stdin] [--quiet|-q] [--keep|-k] [--thin] "
  29 "[--include-tag] [--upload-pack=<git-upload-pack>] [--depth=<n>] "
  30 "[--no-progress] [-v] [<host>:]<directory> [<refs>...]";
  31
  32 #define COMPLETE        (1U << 0)
  33 #define COMMON          (1U << 1)
  34 #define COMMON_REF      (1U << 2)
  35 #define SEEN            (1U << 3)
  36 #define POPPED          (1U << 4)
  37
  38 static int marked;
  39
  40 /*
  41  * After sending this many "have"s if we do not get any new ACK , we
  42  * give up traversing our history.
  43  */
  44 #define MAX_IN_VAIN 256
  45
  46 static struct commit_list *rev_list;
  47 static int non_common_revs, multi_ack, use_sideband;
  48
  49 static void rev_list_push(struct commit *commit, int mark)
  50 {
  51         if (!(commit->object.flags & mark)) {
  52                 commit->object.flags |= mark;
  53
  54                 if (!(commit->object.parsed))
  55                         if (parse_commit(commit))
  56                                 return;
  57
  58                 commit_list_insert_by_date(commit, &rev_list);
  59
  60                 if (!(commit->object.flags & COMMON))
  61                         non_common_revs++;
  62         }
  63 }
  64
  65 static int rev_list_insert_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
  66 {
  67         struct object *o = deref_tag(parse_object(sha1), refname, 0);
  68
  69         if (o && o->type == OBJ_COMMIT)
  70                 rev_list_push((struct commit *)o, SEEN);
  71
  72         return 0;
  73 }
  74
  75 static int clear_marks(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
  76 {
  77         struct object *o = deref_tag(parse_object(sha1), refname, 0);
  78
  79         if (o && o->type == OBJ_COMMIT)
  80                 clear_commit_marks((struct commit *)o,
  81                                    COMMON | COMMON_REF | SEEN | POPPED);
  82         return 0;
  83 }
  84
  85 /*
  86    This function marks a rev and its ancestors as common.
  87    In some cases, it is desirable to mark only the ancestors (for example
  88    when only the server does not yet know that they are common).
  89 */
  90
  91 static void mark_common(struct commit *commit,
  92                 int ancestors_only, int dont_parse)
  93 {
  94         if (commit != NULL && !(commit->object.flags & COMMON)) {
  95                 struct object *o = (struct object *)commit;
  96
  97                 if (!ancestors_only)
  98                         o->flags |= COMMON;
  99
 100                 if (!(o->flags & SEEN))
 101                         rev_list_push(commit, SEEN);
 102                 else {
 103                         struct commit_list *parents;
 104
 105                         if (!ancestors_only && !(o->flags & POPPED))
 106                                 non_common_revs--;
 107                         if (!o->parsed && !dont_parse)
 108                                 if (parse_commit(commit))
 109                                         return;
 110
 111                         for (parents = commit->parents;
 112                                         parents;
 113                                         parents = parents->next)
 114                                 mark_common(parents->item, 0, dont_parse);
 115                 }
 116         }
 117 }
 118
 119 /*
 120   Get the next rev to send, ignoring the common.
 121 */
 122
 123 static const unsigned char *get_rev(void)
 124 {
 125         struct commit *commit = NULL;
 126
 127         while (commit == NULL) {
 128                 unsigned int mark;
 129                 struct commit_list *parents;
 130
 131                 if (rev_list == NULL || non_common_revs == 0)
 132                         return NULL;
 133
 134                 commit = rev_list->item;
 135                 if (!commit->object.parsed)
 136                         parse_commit(commit);
 137                 parents = commit->parents;
 138
 139                 commit->object.flags |= POPPED;
 140                 if (!(commit->object.flags & COMMON))
 141                         non_common_revs--;
 142
 143                 if (commit->object.flags & COMMON) {
 144                         /* do not send "have", and ignore ancestors */
 145                         commit = NULL;
 146                         mark = COMMON | SEEN;
 147                 } else if (commit->object.flags & COMMON_REF)
 148                         /* send "have", and ignore ancestors */
 149                         mark = COMMON | SEEN;
 150                 else
 151                         /* send "have", also for its ancestors */
 152                         mark = SEEN;
 153
 154                 while (parents) {
 155                         if (!(parents->item->object.flags & SEEN))
 156                                 rev_list_push(parents->item, mark);
 157                         if (mark & COMMON)
 158                                 mark_common(parents->item, 1, 0);
 159                         parents = parents->next;
 160                 }
 161
 162                 rev_list = rev_list->next;
 163         }
 164
 165         return commit->object.sha1;
 166 }
 167
 168 enum ack_type {
 169         NAK = 0,
 170         ACK,
 171         ACK_continue,
 172         ACK_common,
 173         ACK_ready
 174 };
 175
 176 static void consume_shallow_list(int fd)
 177 {
 178         if (args.stateless_rpc && args.depth > 0) {
 179                 /* If we sent a depth we will get back "duplicate"
 180                  * shallow and unshallow commands every time there
 181                  * is a block of have lines exchanged.
 182                  */
 183                 char line[1000];
 184                 while (packet_read_line(fd, line, sizeof(line))) {
 185                         if (!prefixcmp(line, "shallow "))
 186                                 continue;
 187                         if (!prefixcmp(line, "unshallow "))
 188                                 continue;
 189                         die("git fetch-pack: expected shallow list");
 190                 }
 191         }
 192 }
 193
 194 struct write_shallow_data {
 195         struct strbuf *out;
 196         int use_pack_protocol;
 197         int count;
 198 };
 199
 200 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
 201 {
 202         struct write_shallow_data *data = cb_data;
 203         const char *hex = sha1_to_hex(graft->sha1);
 204         data->count++;
 205         if (data->use_pack_protocol)
 206                 packet_buf_write(data->out, "shallow %s", hex);
 207         else {
 208                 strbuf_addstr(data->out, hex);
 209                 strbuf_addch(data->out, '\n');
 210         }
 211         return 0;
 212 }
 213
 214 static int write_shallow_commits(struct strbuf *out, int use_pack_protocol)
 215 {
 216         struct write_shallow_data data;
 217         data.out = out;
 218         data.use_pack_protocol = use_pack_protocol;
 219         data.count = 0;
 220         for_each_commit_graft(write_one_shallow, &data);
 221         return data.count;
 222 }
 223
 224 static enum ack_type get_ack(int fd, unsigned char *result_sha1)
 225 {
 226         static char line[1000];
 227         int len = packet_read_line(fd, line, sizeof(line));
 228
 229         if (!len)
 230                 die("git fetch-pack: expected ACK/NAK, got EOF");
 231         if (line[len-1] == '\n')
 232                 line[--len] = 0;
 233         if (!strcmp(line, "NAK"))
 234                 return NAK;
 235         if (!prefixcmp(line, "ACK ")) {
 236                 if (!get_sha1_hex(line+4, result_sha1)) {
 237                         if (strstr(line+45, "continue"))
 238                                 return ACK_continue;
 239                         if (strstr(line+45, "common"))
 240                                 return ACK_common;
 241                         if (strstr(line+45, "ready"))
 242                                 return ACK_ready;
 243                         return ACK;
 244                 }
 245         }
 246         die("git fetch_pack: expected ACK/NAK, got '%s'", line);
 247 }
 248
 249 static void send_request(int fd, struct strbuf *buf)
 250 {
 251         if (args.stateless_rpc) {
 252                 send_sideband(fd, -1, buf->buf, buf->len, LARGE_PACKET_MAX);
 253                 packet_flush(fd);
 254         } else
 255                 safe_write(fd, buf->buf, buf->len);
 256 }
 257
 258 static void insert_one_alternate_ref(const struct ref *ref, void *unused)
 259 {
 260         rev_list_insert_ref(NULL, ref->old_sha1, 0, NULL);
 261 }
 262
 263 #define INITIAL_FLUSH 16
 264 #define PIPESAFE_FLUSH 32
 265 #define LARGE_FLUSH 1024
 266
 267 static int next_flush(int count)
 268 {
 269         int flush_limit = args.stateless_rpc ? LARGE_FLUSH : PIPESAFE_FLUSH;
 270
 271         if (count < flush_limit)
 272                 count <<= 1;
 273         else
 274                 count += flush_limit;
 275         return count;
 276 }
 277
 278 static int find_common(int fd[2], unsigned char *result_sha1,
 279                        struct ref *refs)
 280 {
 281         int fetching;
 282         int count = 0, flushes = 0, flush_at = INITIAL_FLUSH, retval;
 283         const unsigned char *sha1;
 284         unsigned in_vain = 0;
 285         int got_continue = 0;
 286         int got_ready = 0;
 287         struct strbuf req_buf = STRBUF_INIT;
 288         size_t state_len = 0;
 289
 290         if (args.stateless_rpc && multi_ack == 1)
 291                 die("--stateless-rpc requires multi_ack_detailed");
 292         if (marked)
 293                 for_each_ref(clear_marks, NULL);
 294         marked = 1;
 295
 296         for_each_ref(rev_list_insert_ref, NULL);
 297         for_each_alternate_ref(insert_one_alternate_ref, NULL);
 298
 299         fetching = 0;
 300         for ( ; refs ; refs = refs->next) {
 301                 unsigned char *remote = refs->old_sha1;
 302                 const char *remote_hex;
 303                 struct object *o;
 304
 305                 /*
 306                  * If that object is complete (i.e. it is an ancestor of a
 307                  * local ref), we tell them we have it but do not have to
 308                  * tell them about its ancestors, which they already know
 309                  * about.
 310                  *
 311                  * We use lookup_object here because we are only
 312                  * interested in the case we *know* the object is
 313                  * reachable and we have already scanned it.
 314                  */
 315                 if (((o = lookup_object(remote)) != NULL) &&
 316                                 (o->flags & COMPLETE)) {
 317                         continue;
 318                 }
 319
 320                 remote_hex = sha1_to_hex(remote);
 321                 if (!fetching) {
 322                         struct strbuf c = STRBUF_INIT;
 323                         if (multi_ack == 2)     strbuf_addstr(&c, " multi_ack_detailed");
 324                         if (multi_ack == 1)     strbuf_addstr(&c, " multi_ack");
 325                         if (no_done)            strbuf_addstr(&c, " no-done");
 326                         if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
 327                         if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
 328                         if (args.use_thin_pack) strbuf_addstr(&c, " thin-pack");
 329                         if (args.no_progress)   strbuf_addstr(&c, " no-progress");
 330                         if (args.include_tag)   strbuf_addstr(&c, " include-tag");
 331                         if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
 332                         if (agent_supported)    strbuf_addf(&c, " agent=%s",
 333                                                             git_user_agent_sanitized());
 334                         packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
 335                         strbuf_release(&c);
 336                 } else
 337                         packet_buf_write(&req_buf, "want %s\n", remote_hex);
 338                 fetching++;
 339         }
 340
 341         if (!fetching) {
 342                 strbuf_release(&req_buf);
 343                 packet_flush(fd[1]);
 344                 return 1;
 345         }
 346
 347         if (is_repository_shallow())
 348                 write_shallow_commits(&req_buf, 1);
 349         if (args.depth > 0)
 350                 packet_buf_write(&req_buf, "deepen %d", args.depth);
 351         packet_buf_flush(&req_buf);
 352         state_len = req_buf.len;
 353
 354         if (args.depth > 0) {
 355                 char line[1024];
 356                 unsigned char sha1[20];
 357
 358                 send_request(fd[1], &req_buf);
 359                 while (packet_read_line(fd[0], line, sizeof(line))) {
 360                         if (!prefixcmp(line, "shallow ")) {
 361                                 if (get_sha1_hex(line + 8, sha1))
 362                                         die("invalid shallow line: %s", line);
 363                                 register_shallow(sha1);
 364                                 continue;
 365                         }
 366                         if (!prefixcmp(line, "unshallow ")) {
 367                                 if (get_sha1_hex(line + 10, sha1))
 368                                         die("invalid unshallow line: %s", line);
 369                                 if (!lookup_object(sha1))
 370                                         die("object not found: %s", line);
 371                                 /* make sure that it is parsed as shallow */
 372                                 if (!parse_object(sha1))
 373                                         die("error in object: %s", line);
 374                                 if (unregister_shallow(sha1))
 375                                         die("no shallow found: %s", line);
 376                                 continue;
 377                         }
 378                         die("expected shallow/unshallow, got %s", line);
 379                 }
 380         } else if (!args.stateless_rpc)
 381                 send_request(fd[1], &req_buf);
 382
 383         if (!args.stateless_rpc) {
 384                 /* If we aren't using the stateless-rpc interface
 385                  * we don't need to retain the headers.
 386                  */
 387                 strbuf_setlen(&req_buf, 0);
 388                 state_len = 0;
 389         }
 390
 391         flushes = 0;
 392         retval = -1;
 393         while ((sha1 = get_rev())) {
 394                 packet_buf_write(&req_buf, "have %s\n", sha1_to_hex(sha1));
 395                 if (args.verbose)
 396                         fprintf(stderr, "have %s\n", sha1_to_hex(sha1));
 397                 in_vain++;
 398                 if (flush_at <= ++count) {
 399                         int ack;
 400
 401                         packet_buf_flush(&req_buf);
 402                         send_request(fd[1], &req_buf);
 403                         strbuf_setlen(&req_buf, state_len);
 404                         flushes++;
 405                         flush_at = next_flush(count);
 406
 407                         /*
 408                          * We keep one window "ahead" of the other side, and
 409                          * will wait for an ACK only on the next one
 410                          */
 411                         if (!args.stateless_rpc && count == INITIAL_FLUSH)
 412                                 continue;
 413
 414                         consume_shallow_list(fd[0]);
 415                         do {
 416                                 ack = get_ack(fd[0], result_sha1);
 417                                 if (args.verbose && ack)
 418                                         fprintf(stderr, "got ack %d %s\n", ack,
 419                                                         sha1_to_hex(result_sha1));
 420                                 switch (ack) {
 421                                 case ACK:
 422                                         flushes = 0;
 423                                         multi_ack = 0;
 424                                         retval = 0;
 425                                         goto done;
 426                                 case ACK_common:
 427                                 case ACK_ready:
 428                                 case ACK_continue: {
 429                                         struct commit *commit =
 430                                                 lookup_commit(result_sha1);
 431                                         if (!commit)
 432                                                 die("invalid commit %s", sha1_to_hex(result_sha1));
 433                                         if (args.stateless_rpc
 434                                          && ack == ACK_common
 435                                          && !(commit->object.flags & COMMON)) {
 436                                                 /* We need to replay the have for this object
 437                                                  * on the next RPC request so the peer knows
 438                                                  * it is in common with us.
 439                                                  */
 440                                                 const char *hex = sha1_to_hex(result_sha1);
 441                                                 packet_buf_write(&req_buf, "have %s\n", hex);
 442                                                 state_len = req_buf.len;
 443                                         }
 444                                         mark_common(commit, 0, 1);
 445                                         retval = 0;
 446                                         in_vain = 0;
 447                                         got_continue = 1;
 448                                         if (ack == ACK_ready) {
 449                                                 rev_list = NULL;
 450                                                 got_ready = 1;
 451                                         }
 452                                         break;
 453                                         }
 454                                 }
 455                         } while (ack);
 456                         flushes--;
 457                         if (got_continue && MAX_IN_VAIN < in_vain) {
 458                                 if (args.verbose)
 459                                         fprintf(stderr, "giving up\n");
 460                                 break; /* give up */
 461                         }
 462                 }
 463         }
 464 done:
 465         if (!got_ready || !no_done) {
 466                 packet_buf_write(&req_buf, "done\n");
 467                 send_request(fd[1], &req_buf);
 468         }
 469         if (args.verbose)
 470                 fprintf(stderr, "done\n");
 471         if (retval != 0) {
 472                 multi_ack = 0;
 473                 flushes++;
 474         }
 475         strbuf_release(&req_buf);
 476
 477         consume_shallow_list(fd[0]);
 478         while (flushes || multi_ack) {
 479                 int ack = get_ack(fd[0], result_sha1);
 480                 if (ack) {
 481                         if (args.verbose)
 482                                 fprintf(stderr, "got ack (%d) %s\n", ack,
 483                                         sha1_to_hex(result_sha1));
 484                         if (ack == ACK)
 485                                 return 0;
 486                         multi_ack = 1;
 487                         continue;
 488                 }
 489                 flushes--;
 490         }
 491         /* it is no error to fetch into a completely empty repo */
 492         return count ? retval : 0;
 493 }
 494
 495 static struct commit_list *complete;
 496
 497 static int mark_complete(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 498 {
 499         struct object *o = parse_object(sha1);
 500
 501         while (o && o->type == OBJ_TAG) {
 502                 struct tag *t = (struct tag *) o;
 503                 if (!t->tagged)
 504                         break; /* broken repository */
 505                 o->flags |= COMPLETE;
 506                 o = parse_object(t->tagged->sha1);
 507         }
 508         if (o && o->type == OBJ_COMMIT) {
 509                 struct commit *commit = (struct commit *)o;
 510                 if (!(commit->object.flags & COMPLETE)) {
 511                         commit->object.flags |= COMPLETE;
 512                         commit_list_insert_by_date(commit, &complete);
 513                 }
 514         }
 515         return 0;
 516 }
 517
 518 static void mark_recent_complete_commits(unsigned long cutoff)
 519 {
 520         while (complete && cutoff <= complete->item->date) {
 521                 if (args.verbose)
 522                         fprintf(stderr, "Marking %s as complete\n",
 523                                 sha1_to_hex(complete->item->object.sha1));
 524                 pop_most_recent_commit(&complete, COMPLETE);
 525         }
 526 }
 527
 528 static int non_matching_ref(struct string_list_item *item, void *unused)
 529 {
 530         if (item->util) {
 531                 item->util = NULL;
 532                 return 0;
 533         }
 534         else
 535                 return 1;
 536 }
 537
 538 static void filter_refs(struct ref **refs, struct string_list *sought)
 539 {
 540         struct ref *newlist = NULL;
 541         struct ref **newtail = &newlist;
 542         struct ref *ref, *next;
 543         int sought_pos;
 544
 545         sought_pos = 0;
 546         for (ref = *refs; ref; ref = next) {
 547                 next = ref->next;
 548                 if (!memcmp(ref->name, "refs/", 5) &&
 549                     check_refname_format(ref->name + 5, 0))
 550                         ; /* trash */
 551                 else if (args.fetch_all &&
 552                          (!args.depth || prefixcmp(ref->name, "refs/tags/") )) {
 553                         *newtail = ref;
 554                         ref->next = NULL;
 555                         newtail = &ref->next;
 556                         continue;
 557                 }
 558                 else {
 559                         int cmp = -1;
 560                         while (sought_pos < sought->nr) {
 561                                 cmp = strcmp(ref->name, sought->items[sought_pos].string);
 562                                 if (cmp < 0) /* definitely do not have it */
 563                                         break;
 564                                 else if (cmp == 0) { /* definitely have it */
 565                                         sought->items[sought_pos++].util = "matched";
 566                                         *newtail = ref;
 567                                         ref->next = NULL;
 568                                         newtail = &ref->next;
 569                                         break;
 570                                 }
 571                                 else /* might have it; keep looking */
 572                                         sought_pos++;
 573                         }
 574                         if (!cmp)
 575                                 continue; /* we will link it later */
 576                 }
 577                 free(ref);
 578         }
 579
 580         if (!args.fetch_all)
 581                 filter_string_list(sought, 0, non_matching_ref, NULL);
 582         *refs = newlist;
 583 }
 584
 585 static void mark_alternate_complete(const struct ref *ref, void *unused)
 586 {
 587         mark_complete(NULL, ref->old_sha1, 0, NULL);
 588 }
 589
 590 static int everything_local(struct ref **refs, struct string_list *sought)
 591 {
 592         struct ref *ref;
 593         int retval;
 594         unsigned long cutoff = 0;
 595
 596         save_commit_buffer = 0;
 597
 598         for (ref = *refs; ref; ref = ref->next) {
 599                 struct object *o;
 600
 601                 o = parse_object(ref->old_sha1);
 602                 if (!o)
 603                         continue;
 604
 605                 /* We already have it -- which may mean that we were
 606                  * in sync with the other side at some time after
 607                  * that (it is OK if we guess wrong here).
 608                  */
 609                 if (o->type == OBJ_COMMIT) {
 610                         struct commit *commit = (struct commit *)o;
 611                         if (!cutoff || cutoff < commit->date)
 612                                 cutoff = commit->date;
 613                 }
 614         }
 615
 616         if (!args.depth) {
 617                 for_each_ref(mark_complete, NULL);
 618                 for_each_alternate_ref(mark_alternate_complete, NULL);
 619                 if (cutoff)
 620                         mark_recent_complete_commits(cutoff);
 621         }
 622
 623         /*
 624          * Mark all complete remote refs as common refs.
 625          * Don't mark them common yet; the server has to be told so first.
 626          */
 627         for (ref = *refs; ref; ref = ref->next) {
 628                 struct object *o = deref_tag(lookup_object(ref->old_sha1),
 629                                              NULL, 0);
 630
 631                 if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 632                         continue;
 633
 634                 if (!(o->flags & SEEN)) {
 635                         rev_list_push((struct commit *)o, COMMON_REF | SEEN);
 636
 637                         mark_common((struct commit *)o, 1, 1);
 638                 }
 639         }
 640
 641         filter_refs(refs, sought);
 642
 643         for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 644                 const unsigned char *remote = ref->old_sha1;
 645                 unsigned char local[20];
 646                 struct object *o;
 647
 648                 o = lookup_object(remote);
 649                 if (!o || !(o->flags & COMPLETE)) {
 650                         retval = 0;
 651                         if (!args.verbose)
 652                                 continue;
 653                         fprintf(stderr,
 654                                 "want %s (%s)\n", sha1_to_hex(remote),
 655                                 ref->name);
 656                         continue;
 657                 }
 658
 659                 hashcpy(ref->new_sha1, local);
 660                 if (!args.verbose)
 661                         continue;
 662                 fprintf(stderr,
 663                         "already have %s (%s)\n", sha1_to_hex(remote),
 664                         ref->name);
 665         }
 666         return retval;
 667 }
 668
 669 static int sideband_demux(int in, int out, void *data)
 670 {
 671         int *xd = data;
 672
 673         int ret = recv_sideband("fetch-pack", xd[0], out);
 674         close(out);
 675         return ret;
 676 }
 677
 678 static int get_pack(int xd[2], char **pack_lockfile)
 679 {
 680         struct async demux;
 681         const char *argv[20];
 682         char keep_arg[256];
 683         char hdr_arg[256];
 684         const char **av;
 685         int do_keep = args.keep_pack;
 686         struct child_process cmd;
 687
 688         memset(&demux, 0, sizeof(demux));
 689         if (use_sideband) {
 690                 /* xd[] is talking with upload-pack; subprocess reads from
 691                  * xd[0], spits out band#2 to stderr, and feeds us band#1
 692                  * through demux->out.
 693                  */
 694                 demux.proc = sideband_demux;
 695                 demux.data = xd;
 696                 demux.out = -1;
 697                 if (start_async(&demux))
 698                         die("fetch-pack: unable to fork off sideband"
 699                             " demultiplexer");
 700         }
 701         else
 702                 demux.out = xd[0];
 703
 704         memset(&cmd, 0, sizeof(cmd));
 705         cmd.argv = argv;
 706         av = argv;
 707         *hdr_arg = 0;
 708         if (!args.keep_pack && unpack_limit) {
 709                 struct pack_header header;
 710
 711                 if (read_pack_header(demux.out, &header))
 712                         die("protocol error: bad pack header");
 713                 snprintf(hdr_arg, sizeof(hdr_arg),
 714                          "--pack_header=%"PRIu32",%"PRIu32,
 715                          ntohl(header.hdr_version), ntohl(header.hdr_entries));
 716                 if (ntohl(header.hdr_entries) < unpack_limit)
 717                         do_keep = 0;
 718                 else
 719                         do_keep = 1;
 720         }
 721
 722         if (do_keep) {
 723                 if (pack_lockfile)
 724                         cmd.out = -1;
 725                 *av++ = "index-pack";
 726                 *av++ = "--stdin";
 727                 if (!args.quiet && !args.no_progress)
 728                         *av++ = "-v";
 729                 if (args.use_thin_pack)
 730                         *av++ = "--fix-thin";
 731                 if (args.lock_pack || unpack_limit) {
 732                         int s = sprintf(keep_arg,
 733                                         "--keep=fetch-pack %"PRIuMAX " on ", (uintmax_t) getpid());
 734                         if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
 735                                 strcpy(keep_arg + s, "localhost");
 736                         *av++ = keep_arg;
 737                 }
 738         }
 739         else {
 740                 *av++ = "unpack-objects";
 741                 if (args.quiet || args.no_progress)
 742                         *av++ = "-q";
 743         }
 744         if (*hdr_arg)
 745                 *av++ = hdr_arg;
 746         if (fetch_fsck_objects >= 0
 747             ? fetch_fsck_objects
 748             : transfer_fsck_objects >= 0
 749             ? transfer_fsck_objects
 750             : 0)
 751                 *av++ = "--strict";
 752         *av++ = NULL;
 753
 754         cmd.in = demux.out;
 755         cmd.git_cmd = 1;
 756         if (start_command(&cmd))
 757                 die("fetch-pack: unable to fork off %s", argv[0]);
 758         if (do_keep && pack_lockfile) {
 759                 *pack_lockfile = index_pack_lockfile(cmd.out);
 760                 close(cmd.out);
 761         }
 762
 763         if (finish_command(&cmd))
 764                 die("%s failed", argv[0]);
 765         if (use_sideband && finish_async(&demux))
 766                 die("error in sideband demultiplexer");
 767         return 0;
 768 }
 769
 770 static struct ref *do_fetch_pack(int fd[2],
 771                 const struct ref *orig_ref,
 772                 struct string_list *sought,
 773                 char **pack_lockfile)
 774 {
 775         struct ref *ref = copy_ref_list(orig_ref);
 776         unsigned char sha1[20];
 777         const char *agent_feature;
 778         int agent_len;
 779
 780         sort_ref_list(&ref, ref_compare_name);
 781
 782         if (is_repository_shallow() && !server_supports("shallow"))
 783                 die("Server does not support shallow clients");
 784         if (server_supports("multi_ack_detailed")) {
 785                 if (args.verbose)
 786                         fprintf(stderr, "Server supports multi_ack_detailed\n");
 787                 multi_ack = 2;
 788                 if (server_supports("no-done")) {
 789                         if (args.verbose)
 790                                 fprintf(stderr, "Server supports no-done\n");
 791                         if (args.stateless_rpc)
 792                                 no_done = 1;
 793                 }
 794         }
 795         else if (server_supports("multi_ack")) {
 796                 if (args.verbose)
 797                         fprintf(stderr, "Server supports multi_ack\n");
 798                 multi_ack = 1;
 799         }
 800         if (server_supports("side-band-64k")) {
 801                 if (args.verbose)
 802                         fprintf(stderr, "Server supports side-band-64k\n");
 803                 use_sideband = 2;
 804         }
 805         else if (server_supports("side-band")) {
 806                 if (args.verbose)
 807                         fprintf(stderr, "Server supports side-band\n");
 808                 use_sideband = 1;
 809         }
 810         if (!server_supports("thin-pack"))
 811                 args.use_thin_pack = 0;
 812         if (!server_supports("no-progress"))
 813                 args.no_progress = 0;
 814         if (!server_supports("include-tag"))
 815                 args.include_tag = 0;
 816         if (server_supports("ofs-delta")) {
 817                 if (args.verbose)
 818                         fprintf(stderr, "Server supports ofs-delta\n");
 819         } else
 820                 prefer_ofs_delta = 0;
 821
 822         if ((agent_feature = server_feature_value("agent", &agent_len))) {
 823                 agent_supported = 1;
 824                 if (args.verbose && agent_len)
 825                         fprintf(stderr, "Server version is %.*s\n",
 826                                 agent_len, agent_feature);
 827         }
 828
 829         if (everything_local(&ref, sought)) {
 830                 packet_flush(fd[1]);
 831                 goto all_done;
 832         }
 833         if (find_common(fd, sha1, ref) < 0)
 834                 if (!args.keep_pack)
 835                         /* When cloning, it is not unusual to have
 836                          * no common commit.
 837                          */
 838                         warning("no common commits");
 839
 840         if (args.stateless_rpc)
 841                 packet_flush(fd[1]);
 842         if (get_pack(fd, pack_lockfile))
 843                 die("git fetch-pack: fetch failed.");
 844
 845  all_done:
 846         return ref;
 847 }
 848
 849 static int fetch_pack_config(const char *var, const char *value, void *cb)
 850 {
 851         if (strcmp(var, "fetch.unpacklimit") == 0) {
 852                 fetch_unpack_limit = git_config_int(var, value);
 853                 return 0;
 854         }
 855
 856         if (strcmp(var, "transfer.unpacklimit") == 0) {
 857                 transfer_unpack_limit = git_config_int(var, value);
 858                 return 0;
 859         }
 860
 861         if (strcmp(var, "repack.usedeltabaseoffset") == 0) {
 862                 prefer_ofs_delta = git_config_bool(var, value);
 863                 return 0;
 864         }
 865
 866         if (!strcmp(var, "fetch.fsckobjects")) {
 867                 fetch_fsck_objects = git_config_bool(var, value);
 868                 return 0;
 869         }
 870
 871         if (!strcmp(var, "transfer.fsckobjects")) {
 872                 transfer_fsck_objects = git_config_bool(var, value);
 873                 return 0;
 874         }
 875
 876         return git_default_config(var, value, cb);
 877 }
 878
 879 static struct lock_file lock;
 880
 881 static void fetch_pack_setup(void)
 882 {
 883         static int did_setup;
 884         if (did_setup)
 885                 return;
 886         git_config(fetch_pack_config, NULL);
 887         if (0 <= transfer_unpack_limit)
 888                 unpack_limit = transfer_unpack_limit;
 889         else if (0 <= fetch_unpack_limit)
 890                 unpack_limit = fetch_unpack_limit;
 891         did_setup = 1;
 892 }
 893
 894 int cmd_fetch_pack(int argc, const char **argv, const char *prefix)
 895 {
 896         int i, ret;
 897         struct ref *ref = NULL;
 898         const char *dest = NULL;
 899         struct string_list sought = STRING_LIST_INIT_DUP;
 900         int fd[2];
 901         char *pack_lockfile = NULL;
 902         char **pack_lockfile_ptr = NULL;
 903         struct child_process *conn;
 904
 905         packet_trace_identity("fetch-pack");
 906
 907         for (i = 1; i < argc && *argv[i] == '-'; i++) {
 908                 const char *arg = argv[i];
 909
 910                 if (!prefixcmp(arg, "--upload-pack=")) {
 911                         args.uploadpack = arg + 14;
 912                         continue;
 913                 }
 914                 if (!prefixcmp(arg, "--exec=")) {
 915                         args.uploadpack = arg + 7;
 916                         continue;
 917                 }
 918                 if (!strcmp("--quiet", arg) || !strcmp("-q", arg)) {
 919                         args.quiet = 1;
 920                         continue;
 921                 }
 922                 if (!strcmp("--keep", arg) || !strcmp("-k", arg)) {
 923                         args.lock_pack = args.keep_pack;
 924                         args.keep_pack = 1;
 925                         continue;
 926                 }
 927                 if (!strcmp("--thin", arg)) {
 928                         args.use_thin_pack = 1;
 929                         continue;
 930                 }
 931                 if (!strcmp("--include-tag", arg)) {
 932                         args.include_tag = 1;
 933                         continue;
 934                 }
 935                 if (!strcmp("--all", arg)) {
 936                         args.fetch_all = 1;
 937                         continue;
 938                 }
 939                 if (!strcmp("--stdin", arg)) {
 940                         args.stdin_refs = 1;
 941                         continue;
 942                 }
 943                 if (!strcmp("-v", arg)) {
 944                         args.verbose = 1;
 945                         continue;
 946                 }
 947                 if (!prefixcmp(arg, "--depth=")) {
 948                         args.depth = strtol(arg + 8, NULL, 0);
 949                         continue;
 950                 }
 951                 if (!strcmp("--no-progress", arg)) {
 952                         args.no_progress = 1;
 953                         continue;
 954                 }
 955                 if (!strcmp("--stateless-rpc", arg)) {
 956                         args.stateless_rpc = 1;
 957                         continue;
 958                 }
 959                 if (!strcmp("--lock-pack", arg)) {
 960                         args.lock_pack = 1;
 961                         pack_lockfile_ptr = &pack_lockfile;
 962                         continue;
 963                 }
 964                 usage(fetch_pack_usage);
 965         }
 966
 967         if (i < argc)
 968                 dest = argv[i++];
 969         else
 970                 usage(fetch_pack_usage);
 971
 972         /*
 973          * Copy refs from cmdline to growable list, then append any
 974          * refs from the standard input:
 975          */
 976         for (; i < argc; i++)
 977                 string_list_append(&sought, xstrdup(argv[i]));
 978         if (args.stdin_refs) {
 979                 if (args.stateless_rpc) {
 980                         /* in stateless RPC mode we use pkt-line to read
 981                          * from stdin, until we get a flush packet
 982                          */
 983                         static char line[1000];
 984                         for (;;) {
 985                                 int n = packet_read_line(0, line, sizeof(line));
 986                                 if (!n)
 987                                         break;
 988                                 if (line[n-1] == '\n')
 989                                         n--;
 990                                 string_list_append(&sought, xmemdupz(line, n));
 991                         }
 992                 }
 993                 else {
 994                         /* read from stdin one ref per line, until EOF */
 995                         struct strbuf line = STRBUF_INIT;
 996                         while (strbuf_getline(&line, stdin, '\n') != EOF)
 997                                 string_list_append(&sought, strbuf_detach(&line, NULL));
 998                         strbuf_release(&line);
 999                 }
1000         }
1001
1002         if (args.stateless_rpc) {
1003                 conn = NULL;
1004                 fd[0] = 0;
1005                 fd[1] = 1;
1006         } else {
1007                 conn = git_connect(fd, dest, args.uploadpack,
1008                                    args.verbose ? CONNECT_VERBOSE : 0);
1009         }
1010
1011         get_remote_heads(fd[0], &ref, 0, NULL);
1012
1013         ref = fetch_pack(&args, fd, conn, ref, dest,
1014                          &sought, pack_lockfile_ptr);
1015         if (pack_lockfile) {
1016                 printf("lock %s\n", pack_lockfile);
1017                 fflush(stdout);
1018         }
1019         close(fd[0]);
1020         close(fd[1]);
1021         if (finish_connect(conn))
1022                 ref = NULL;
1023         ret = !ref;
1024
1025         if (!ret && sought.nr) {
1026                 /* If the heads to pull were given, we should have
1027                  * consumed all of them by matching the remote.
1028                  * Otherwise, 'git fetch remote no-such-ref' would
1029                  * silently succeed without issuing an error.
1030                  */
1031                 for (i = 0; i < sought.nr; i++)
1032                         error("no such remote ref %s", sought.items[i].string);
1033                 ret = 1;
1034         }
1035         while (ref) {
1036                 printf("%s %s\n",
1037                        sha1_to_hex(ref->old_sha1), ref->name);
1038                 ref = ref->next;
1039         }
1040
1041         return ret;
1042 }
1043
1044 struct ref *fetch_pack(struct fetch_pack_args *my_args,
1045                        int fd[], struct child_process *conn,
1046                        const struct ref *ref,
1047                        const char *dest,
1048                        struct string_list *sought,
1049                        char **pack_lockfile)
1050 {
1051         struct stat st;
1052         struct ref *ref_cpy;
1053
1054         fetch_pack_setup();
1055         if (&args != my_args)
1056                 memcpy(&args, my_args, sizeof(args));
1057         if (args.depth > 0) {
1058                 if (stat(git_path("shallow"), &st))
1059                         st.st_mtime = 0;
1060         }
1061
1062         if (sought->nr) {
1063                 sort_string_list(sought);
1064                 string_list_remove_duplicates(sought, 0);
1065         }
1066
1067         if (!ref) {
1068                 packet_flush(fd[1]);
1069                 die("no matching remote head");
1070         }
1071         ref_cpy = do_fetch_pack(fd, ref, sought, pack_lockfile);
1072
1073         if (args.depth > 0) {
1074                 struct cache_time mtime;
1075                 struct strbuf sb = STRBUF_INIT;
1076                 char *shallow = git_path("shallow");
1077                 int fd;
1078
1079                 mtime.sec = st.st_mtime;
1080                 mtime.nsec = ST_MTIME_NSEC(st);
1081                 if (stat(shallow, &st)) {
1082                         if (mtime.sec)
1083                                 die("shallow file was removed during fetch");
1084                 } else if (st.st_mtime != mtime.sec
1085 #ifdef USE_NSEC
1086                                 || ST_MTIME_NSEC(st) != mtime.nsec
1087 #endif
1088                           )
1089                         die("shallow file was changed during fetch");
1090
1091                 fd = hold_lock_file_for_update(&lock, shallow,
1092                                                LOCK_DIE_ON_ERROR);
1093                 if (!write_shallow_commits(&sb, 0)
1094                  || write_in_full(fd, sb.buf, sb.len) != sb.len) {
1095                         unlink_or_warn(shallow);
1096                         rollback_lock_file(&lock);
1097                 } else {
1098                         commit_lock_file(&lock);
1099                 }
1100                 strbuf_release(&sb);
1101         }
1102
1103         reprepare_packed_git();
1104         return ref_cpy;
1105 }