builtin-fetch.c

   1 /*
   2  * "git fetch"
   3  */
   4 #include "cache.h"
   5 #include "refs.h"
   6 #include "commit.h"
   7 #include "builtin.h"
   8 #include "path-list.h"
   9 #include "remote.h"
  10 #include "transport.h"
  11 #include "run-command.h"
  12 #include "parse-options.h"
  13
  14 static const char * const builtin_fetch_usage[] = {
  15         "git-fetch [options] [<repository> <refspec>...]",
  16         NULL
  17 };
  18
  19 enum {
  20         TAGS_UNSET = 0,
  21         TAGS_DEFAULT = 1,
  22         TAGS_SET = 2
  23 };
  24
  25 static int append, force, keep, update_head_ok, verbose, quiet;
  26 static int tags = TAGS_DEFAULT;
  27 static const char *depth;
  28 static const char *upload_pack;
  29 static struct strbuf default_rla = STRBUF_INIT;
  30 static struct transport *transport;
  31
  32 static struct option builtin_fetch_options[] = {
  33         OPT__QUIET(&quiet),
  34         OPT__VERBOSE(&verbose),
  35         OPT_BOOLEAN('a', "append", &append,
  36                     "append to .git/FETCH_HEAD instead of overwriting"),
  37         OPT_STRING(0, "upload-pack", &upload_pack, "PATH",
  38                    "path to upload pack on remote end"),
  39         OPT_BOOLEAN('f', "force", &force,
  40                     "force overwrite of local branch"),
  41         OPT_SET_INT('t', "tags", &tags,
  42                     "fetch all tags and associated objects", TAGS_SET),
  43         OPT_BOOLEAN('k', "keep", &keep, "keep downloaded pack"),
  44         OPT_BOOLEAN('u', "update-head-ok", &update_head_ok,
  45                     "allow updating of HEAD ref"),
  46         OPT_STRING(0, "depth", &depth, "DEPTH",
  47                    "deepen history of shallow clone"),
  48         OPT_END()
  49 };
  50
  51 static void unlock_pack(void)
  52 {
  53         if (transport)
  54                 transport_unlock_pack(transport);
  55 }
  56
  57 static void unlock_pack_on_signal(int signo)
  58 {
  59         unlock_pack();
  60         signal(SIGINT, SIG_DFL);
  61         raise(signo);
  62 }
  63
  64 static void add_merge_config(struct ref **head,
  65                            const struct ref *remote_refs,
  66                            struct branch *branch,
  67                            struct ref ***tail)
  68 {
  69         int i;
  70
  71         for (i = 0; i < branch->merge_nr; i++) {
  72                 struct ref *rm, **old_tail = *tail;
  73                 struct refspec refspec;
  74
  75                 for (rm = *head; rm; rm = rm->next) {
  76                         if (branch_merge_matches(branch, i, rm->name)) {
  77                                 rm->merge = 1;
  78                                 break;
  79                         }
  80                 }
  81                 if (rm)
  82                         continue;
  83
  84                 /*
  85                  * Not fetched to a tracking branch?  We need to fetch
  86                  * it anyway to allow this branch's "branch.$name.merge"
  87                  * to be honored by git-pull, but we do not have to
  88                  * fail if branch.$name.merge is misconfigured to point
  89                  * at a nonexisting branch.  If we were indeed called by
  90                  * git-pull, it will notice the misconfiguration because
  91                  * there is no entry in the resulting FETCH_HEAD marked
  92                  * for merging.
  93                  */
  94                 refspec.src = branch->merge[i]->src;
  95                 refspec.dst = NULL;
  96                 refspec.pattern = 0;
  97                 refspec.force = 0;
  98                 get_fetch_map(remote_refs, &refspec, tail, 1);
  99                 for (rm = *old_tail; rm; rm = rm->next)
 100                         rm->merge = 1;
 101         }
 102 }
 103
 104 static void find_non_local_tags(struct transport *transport,
 105                         struct ref **head,
 106                         struct ref ***tail);
 107
 108 static struct ref *get_ref_map(struct transport *transport,
 109                                struct refspec *refs, int ref_count, int tags,
 110                                int *autotags)
 111 {
 112         int i;
 113         struct ref *rm;
 114         struct ref *ref_map = NULL;
 115         struct ref **tail = &ref_map;
 116
 117         const struct ref *remote_refs = transport_get_remote_refs(transport);
 118
 119         if (ref_count || tags == TAGS_SET) {
 120                 for (i = 0; i < ref_count; i++) {
 121                         get_fetch_map(remote_refs, &refs[i], &tail, 0);
 122                         if (refs[i].dst && refs[i].dst[0])
 123                                 *autotags = 1;
 124                 }
 125                 /* Merge everything on the command line, but not --tags */
 126                 for (rm = ref_map; rm; rm = rm->next)
 127                         rm->merge = 1;
 128                 if (tags == TAGS_SET) {
 129                         struct refspec refspec;
 130                         refspec.src = "refs/tags/";
 131                         refspec.dst = "refs/tags/";
 132                         refspec.pattern = 1;
 133                         refspec.force = 0;
 134                         get_fetch_map(remote_refs, &refspec, &tail, 0);
 135                 }
 136         } else {
 137                 /* Use the defaults */
 138                 struct remote *remote = transport->remote;
 139                 struct branch *branch = branch_get(NULL);
 140                 int has_merge = branch_has_merge_config(branch);
 141                 if (remote && (remote->fetch_refspec_nr || has_merge)) {
 142                         for (i = 0; i < remote->fetch_refspec_nr; i++) {
 143                                 get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
 144                                 if (remote->fetch[i].dst &&
 145                                     remote->fetch[i].dst[0])
 146                                         *autotags = 1;
 147                                 if (!i && !has_merge && ref_map &&
 148                                     !remote->fetch[0].pattern)
 149                                         ref_map->merge = 1;
 150                         }
 151                         /*
 152                          * if the remote we're fetching from is the same
 153                          * as given in branch.<name>.remote, we add the
 154                          * ref given in branch.<name>.merge, too.
 155                          */
 156                         if (has_merge &&
 157                             !strcmp(branch->remote_name, remote->name))
 158                                 add_merge_config(&ref_map, remote_refs, branch, &tail);
 159                 } else {
 160                         ref_map = get_remote_ref(remote_refs, "HEAD");
 161                         if (!ref_map)
 162                                 die("Couldn't find remote ref HEAD");
 163                         ref_map->merge = 1;
 164                         tail = &ref_map->next;
 165                 }
 166         }
 167         if (tags == TAGS_DEFAULT && *autotags)
 168                 find_non_local_tags(transport, &ref_map, &tail);
 169         ref_remove_duplicates(ref_map);
 170
 171         return ref_map;
 172 }
 173
 174 static int s_update_ref(const char *action,
 175                         struct ref *ref,
 176                         int check_old)
 177 {
 178         char msg[1024];
 179         char *rla = getenv("GIT_REFLOG_ACTION");
 180         static struct ref_lock *lock;
 181
 182         if (!rla)
 183                 rla = default_rla.buf;
 184         snprintf(msg, sizeof(msg), "%s: %s", rla, action);
 185         lock = lock_any_ref_for_update(ref->name,
 186                                        check_old ? ref->old_sha1 : NULL, 0);
 187         if (!lock)
 188                 return 1;
 189         if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
 190                 return 1;
 191         return 0;
 192 }
 193
 194 #define SUMMARY_WIDTH (2 * DEFAULT_ABBREV + 3)
 195 #define REFCOL_WIDTH  10
 196
 197 static int update_local_ref(struct ref *ref,
 198                             const char *remote,
 199                             int verbose,
 200                             char *display)
 201 {
 202         struct commit *current = NULL, *updated;
 203         enum object_type type;
 204         struct branch *current_branch = branch_get(NULL);
 205         const char *pretty_ref = ref->name + (
 206                 !prefixcmp(ref->name, "refs/heads/") ? 11 :
 207                 !prefixcmp(ref->name, "refs/tags/") ? 10 :
 208                 !prefixcmp(ref->name, "refs/remotes/") ? 13 :
 209                 0);
 210
 211         *display = 0;
 212         type = sha1_object_info(ref->new_sha1, NULL);
 213         if (type < 0)
 214                 die("object %s not found", sha1_to_hex(ref->new_sha1));
 215
 216         if (!*ref->name) {
 217                 /* Not storing */
 218                 if (verbose)
 219                         sprintf(display, "* branch %s -> FETCH_HEAD", remote);
 220                 return 0;
 221         }
 222
 223         if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
 224                 if (verbose)
 225                         sprintf(display, "= %-*s %-*s -> %s", SUMMARY_WIDTH,
 226                                 "[up to date]", REFCOL_WIDTH, remote,
 227                                 pretty_ref);
 228                 return 0;
 229         }
 230
 231         if (current_branch &&
 232             !strcmp(ref->name, current_branch->name) &&
 233             !(update_head_ok || is_bare_repository()) &&
 234             !is_null_sha1(ref->old_sha1)) {
 235                 /*
 236                  * If this is the head, and it's not okay to update
 237                  * the head, and the old value of the head isn't empty...
 238                  */
 239                 sprintf(display, "! %-*s %-*s -> %s  (can't fetch in current branch)",
 240                         SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
 241                         pretty_ref);
 242                 return 1;
 243         }
 244
 245         if (!is_null_sha1(ref->old_sha1) &&
 246             !prefixcmp(ref->name, "refs/tags/")) {
 247                 sprintf(display, "- %-*s %-*s -> %s",
 248                         SUMMARY_WIDTH, "[tag update]", REFCOL_WIDTH, remote,
 249                         pretty_ref);
 250                 return s_update_ref("updating tag", ref, 0);
 251         }
 252
 253         current = lookup_commit_reference_gently(ref->old_sha1, 1);
 254         updated = lookup_commit_reference_gently(ref->new_sha1, 1);
 255         if (!current || !updated) {
 256                 const char *msg;
 257                 const char *what;
 258                 if (!strncmp(ref->name, "refs/tags/", 10)) {
 259                         msg = "storing tag";
 260                         what = "[new tag]";
 261                 }
 262                 else {
 263                         msg = "storing head";
 264                         what = "[new branch]";
 265                 }
 266
 267                 sprintf(display, "* %-*s %-*s -> %s", SUMMARY_WIDTH, what,
 268                         REFCOL_WIDTH, remote, pretty_ref);
 269                 return s_update_ref(msg, ref, 0);
 270         }
 271
 272         if (in_merge_bases(current, &updated, 1)) {
 273                 char quickref[83];
 274                 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 275                 strcat(quickref, "..");
 276                 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 277                 sprintf(display, "  %-*s %-*s -> %s", SUMMARY_WIDTH, quickref,
 278                         REFCOL_WIDTH, remote, pretty_ref);
 279                 return s_update_ref("fast forward", ref, 1);
 280         } else if (force || ref->force) {
 281                 char quickref[84];
 282                 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 283                 strcat(quickref, "...");
 284                 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 285                 sprintf(display, "+ %-*s %-*s -> %s  (forced update)",
 286                         SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote, pretty_ref);
 287                 return s_update_ref("forced-update", ref, 1);
 288         } else {
 289                 sprintf(display, "! %-*s %-*s -> %s  (non fast forward)",
 290                         SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
 291                         pretty_ref);
 292                 return 1;
 293         }
 294 }
 295
 296 static int store_updated_refs(const char *url, struct ref *ref_map)
 297 {
 298         FILE *fp;
 299         struct commit *commit;
 300         int url_len, i, note_len, shown_url = 0;
 301         char note[1024];
 302         const char *what, *kind;
 303         struct ref *rm;
 304         char *filename = git_path("FETCH_HEAD");
 305
 306         fp = fopen(filename, "a");
 307         if (!fp)
 308                 return error("cannot open %s: %s\n", filename, strerror(errno));
 309         for (rm = ref_map; rm; rm = rm->next) {
 310                 struct ref *ref = NULL;
 311
 312                 if (rm->peer_ref) {
 313                         ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
 314                         strcpy(ref->name, rm->peer_ref->name);
 315                         hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
 316                         hashcpy(ref->new_sha1, rm->old_sha1);
 317                         ref->force = rm->peer_ref->force;
 318                 }
 319
 320                 commit = lookup_commit_reference_gently(rm->old_sha1, 1);
 321                 if (!commit)
 322                         rm->merge = 0;
 323
 324                 if (!strcmp(rm->name, "HEAD")) {
 325                         kind = "";
 326                         what = "";
 327                 }
 328                 else if (!prefixcmp(rm->name, "refs/heads/")) {
 329                         kind = "branch";
 330                         what = rm->name + 11;
 331                 }
 332                 else if (!prefixcmp(rm->name, "refs/tags/")) {
 333                         kind = "tag";
 334                         what = rm->name + 10;
 335                 }
 336                 else if (!prefixcmp(rm->name, "refs/remotes/")) {
 337                         kind = "remote branch";
 338                         what = rm->name + 13;
 339                 }
 340                 else {
 341                         kind = "";
 342                         what = rm->name;
 343                 }
 344
 345                 url_len = strlen(url);
 346                 for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
 347                         ;
 348                 url_len = i + 1;
 349                 if (4 < i && !strncmp(".git", url + i - 3, 4))
 350                         url_len = i - 3;
 351
 352                 note_len = 0;
 353                 if (*what) {
 354                         if (*kind)
 355                                 note_len += sprintf(note + note_len, "%s ",
 356                                                     kind);
 357                         note_len += sprintf(note + note_len, "'%s' of ", what);
 358                 }
 359                 note_len += sprintf(note + note_len, "%.*s", url_len, url);
 360                 fprintf(fp, "%s\t%s\t%s\n",
 361                         sha1_to_hex(commit ? commit->object.sha1 :
 362                                     rm->old_sha1),
 363                         rm->merge ? "" : "not-for-merge",
 364                         note);
 365
 366                 if (ref) {
 367                         update_local_ref(ref, what, verbose, note);
 368                         if (*note) {
 369                                 if (!shown_url) {
 370                                         fprintf(stderr, "From %.*s\n",
 371                                                         url_len, url);
 372                                         shown_url = 1;
 373                                 }
 374                                 fprintf(stderr, " %s\n", note);
 375                         }
 376                 }
 377         }
 378         fclose(fp);
 379         return 0;
 380 }
 381
 382 /*
 383  * We would want to bypass the object transfer altogether if
 384  * everything we are going to fetch already exists and connected
 385  * locally.
 386  *
 387  * The refs we are going to fetch are in to_fetch (nr_heads in
 388  * total).  If running
 389  *
 390  *  $ git-rev-list --objects to_fetch[0] to_fetch[1] ... --not --all
 391  *
 392  * does not error out, that means everything reachable from the
 393  * refs we are going to fetch exists and is connected to some of
 394  * our existing refs.
 395  */
 396 static int quickfetch(struct ref *ref_map)
 397 {
 398         struct child_process revlist;
 399         struct ref *ref;
 400         char **argv;
 401         int i, err;
 402
 403         /*
 404          * If we are deepening a shallow clone we already have these
 405          * objects reachable.  Running rev-list here will return with
 406          * a good (0) exit status and we'll bypass the fetch that we
 407          * really need to perform.  Claiming failure now will ensure
 408          * we perform the network exchange to deepen our history.
 409          */
 410         if (depth)
 411                 return -1;
 412
 413         for (i = 0, ref = ref_map; ref; ref = ref->next)
 414                 i++;
 415         if (!i)
 416                 return 0;
 417
 418         argv = xmalloc(sizeof(*argv) * (i + 6));
 419         i = 0;
 420         argv[i++] = xstrdup("rev-list");
 421         argv[i++] = xstrdup("--quiet");
 422         argv[i++] = xstrdup("--objects");
 423         for (ref = ref_map; ref; ref = ref->next)
 424                 argv[i++] = xstrdup(sha1_to_hex(ref->old_sha1));
 425         argv[i++] = xstrdup("--not");
 426         argv[i++] = xstrdup("--all");
 427         argv[i++] = NULL;
 428
 429         memset(&revlist, 0, sizeof(revlist));
 430         revlist.argv = (const char**)argv;
 431         revlist.git_cmd = 1;
 432         revlist.no_stdin = 1;
 433         revlist.no_stdout = 1;
 434         revlist.no_stderr = 1;
 435         err = run_command(&revlist);
 436
 437         for (i = 0; argv[i]; i++)
 438                 free(argv[i]);
 439         free(argv);
 440         return err;
 441 }
 442
 443 static int fetch_refs(struct transport *transport, struct ref *ref_map)
 444 {
 445         int ret = quickfetch(ref_map);
 446         if (ret)
 447                 ret = transport_fetch_refs(transport, ref_map);
 448         if (!ret)
 449                 ret |= store_updated_refs(transport->url, ref_map);
 450         transport_unlock_pack(transport);
 451         return ret;
 452 }
 453
 454 static int add_existing(const char *refname, const unsigned char *sha1,
 455                         int flag, void *cbdata)
 456 {
 457         struct path_list *list = (struct path_list *)cbdata;
 458         path_list_insert(refname, list);
 459         return 0;
 460 }
 461
 462 static void find_non_local_tags(struct transport *transport,
 463                         struct ref **head,
 464                         struct ref ***tail)
 465 {
 466         struct path_list existing_refs = { NULL, 0, 0, 0 };
 467         struct path_list new_refs = { NULL, 0, 0, 1 };
 468         char *ref_name;
 469         int ref_name_len;
 470         const unsigned char *ref_sha1;
 471         const struct ref *tag_ref;
 472         struct ref *rm = NULL;
 473         const struct ref *ref;
 474
 475         for_each_ref(add_existing, &existing_refs);
 476         for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
 477                 if (prefixcmp(ref->name, "refs/tags"))
 478                         continue;
 479
 480                 ref_name = xstrdup(ref->name);
 481                 ref_name_len = strlen(ref_name);
 482                 ref_sha1 = ref->old_sha1;
 483
 484                 if (!strcmp(ref_name + ref_name_len - 3, "^{}")) {
 485                         ref_name[ref_name_len - 3] = 0;
 486                         tag_ref = transport_get_remote_refs(transport);
 487                         while (tag_ref) {
 488                                 if (!strcmp(tag_ref->name, ref_name)) {
 489                                         ref_sha1 = tag_ref->old_sha1;
 490                                         break;
 491                                 }
 492                                 tag_ref = tag_ref->next;
 493                         }
 494                 }
 495
 496                 if (!path_list_has_path(&existing_refs, ref_name) &&
 497                     !path_list_has_path(&new_refs, ref_name) &&
 498                     has_sha1_file(ref->old_sha1)) {
 499                         path_list_insert(ref_name, &new_refs);
 500
 501                         rm = alloc_ref(strlen(ref_name) + 1);
 502                         strcpy(rm->name, ref_name);
 503                         rm->peer_ref = alloc_ref(strlen(ref_name) + 1);
 504                         strcpy(rm->peer_ref->name, ref_name);
 505                         hashcpy(rm->old_sha1, ref_sha1);
 506
 507                         **tail = rm;
 508                         *tail = &rm->next;
 509                 }
 510                 free(ref_name);
 511         }
 512         path_list_clear(&existing_refs, 0);
 513         path_list_clear(&new_refs, 0);
 514 }
 515
 516 static int do_fetch(struct transport *transport,
 517                     struct refspec *refs, int ref_count)
 518 {
 519         struct ref *ref_map;
 520         struct ref *rm;
 521         int autotags = (transport->remote->fetch_tags == 1);
 522         if (transport->remote->fetch_tags == 2 && tags != TAGS_UNSET)
 523                 tags = TAGS_SET;
 524         if (transport->remote->fetch_tags == -1)
 525                 tags = TAGS_UNSET;
 526
 527         if (!transport->get_refs_list || !transport->fetch)
 528                 die("Don't know how to fetch from %s", transport->url);
 529
 530         /* if not appending, truncate FETCH_HEAD */
 531         if (!append) {
 532                 char *filename = git_path("FETCH_HEAD");
 533                 FILE *fp = fopen(filename, "w");
 534                 if (!fp)
 535                         return error("cannot open %s: %s\n", filename, strerror(errno));
 536                 fclose(fp);
 537         }
 538
 539         ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
 540
 541         for (rm = ref_map; rm; rm = rm->next) {
 542                 if (rm->peer_ref)
 543                         read_ref(rm->peer_ref->name, rm->peer_ref->old_sha1);
 544         }
 545
 546         if (fetch_refs(transport, ref_map)) {
 547                 free_refs(ref_map);
 548                 return 1;
 549         }
 550         free_refs(ref_map);
 551
 552         /* if neither --no-tags nor --tags was specified, do automated tag
 553          * following ... */
 554         if (tags == TAGS_DEFAULT && autotags) {
 555                 struct ref **tail = &ref_map;
 556                 ref_map = NULL;
 557                 find_non_local_tags(transport, &ref_map, &tail);
 558                 if (ref_map) {
 559                         transport_set_option(transport, TRANS_OPT_DEPTH, "0");
 560                         fetch_refs(transport, ref_map);
 561                 }
 562                 free_refs(ref_map);
 563         }
 564
 565         transport_disconnect(transport);
 566
 567         return 0;
 568 }
 569
 570 static void set_option(const char *name, const char *value)
 571 {
 572         int r = transport_set_option(transport, name, value);
 573         if (r < 0)
 574                 die("Option \"%s\" value \"%s\" is not valid for %s\n",
 575                         name, value, transport->url);
 576         if (r > 0)
 577                 warning("Option \"%s\" is ignored for %s\n",
 578                         name, transport->url);
 579 }
 580
 581 int cmd_fetch(int argc, const char **argv, const char *prefix)
 582 {
 583         struct remote *remote;
 584         int i;
 585         static const char **refs = NULL;
 586         int ref_nr = 0;
 587
 588         /* Record the command line for the reflog */
 589         strbuf_addstr(&default_rla, "fetch");
 590         for (i = 1; i < argc; i++)
 591                 strbuf_addf(&default_rla, " %s", argv[i]);
 592
 593         argc = parse_options(argc, argv,
 594                              builtin_fetch_options, builtin_fetch_usage, 0);
 595
 596         if (argc == 0)
 597                 remote = remote_get(NULL);
 598         else
 599                 remote = remote_get(argv[0]);
 600
 601         transport = transport_get(remote, remote->url[0]);
 602         if (verbose >= 2)
 603                 transport->verbose = 1;
 604         if (quiet)
 605                 transport->verbose = -1;
 606         if (upload_pack)
 607                 set_option(TRANS_OPT_UPLOADPACK, upload_pack);
 608         if (keep)
 609                 set_option(TRANS_OPT_KEEP, "yes");
 610         if (depth)
 611                 set_option(TRANS_OPT_DEPTH, depth);
 612
 613         if (!transport->url)
 614                 die("Where do you want to fetch from today?");
 615
 616         if (argc > 1) {
 617                 int j = 0;
 618                 refs = xcalloc(argc + 1, sizeof(const char *));
 619                 for (i = 1; i < argc; i++) {
 620                         if (!strcmp(argv[i], "tag")) {
 621                                 char *ref;
 622                                 i++;
 623                                 ref = xmalloc(strlen(argv[i]) * 2 + 22);
 624                                 strcpy(ref, "refs/tags/");
 625                                 strcat(ref, argv[i]);
 626                                 strcat(ref, ":refs/tags/");
 627                                 strcat(ref, argv[i]);
 628                                 refs[j++] = ref;
 629                         } else
 630                                 refs[j++] = argv[i];
 631                 }
 632                 refs[j] = NULL;
 633                 ref_nr = j;
 634         }
 635
 636         signal(SIGINT, unlock_pack_on_signal);
 637         atexit(unlock_pack);
 638         return do_fetch(transport, parse_ref_spec(ref_nr, refs), ref_nr);
 639 }