builtin-fetch.con commit remote.c: Fix overtight refspec validation (46220ca)
   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
  14static const char * const builtin_fetch_usage[] = {
  15        "git-fetch [options] [<repository> <refspec>...]",
  16        NULL
  17};
  18
  19enum {
  20        TAGS_UNSET = 0,
  21        TAGS_DEFAULT = 1,
  22        TAGS_SET = 2
  23};
  24
  25static int append, force, keep, update_head_ok, verbose, quiet;
  26static int tags = TAGS_DEFAULT;
  27static const char *depth;
  28static const char *upload_pack;
  29static struct strbuf default_rla = STRBUF_INIT;
  30static struct transport *transport;
  31
  32static 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_SET_INT('n', NULL, &tags,
  44                    "do not fetch all tags (--no-tags)", TAGS_UNSET),
  45        OPT_BOOLEAN('k', "keep", &keep, "keep downloaded pack"),
  46        OPT_BOOLEAN('u', "update-head-ok", &update_head_ok,
  47                    "allow updating of HEAD ref"),
  48        OPT_STRING(0, "depth", &depth, "DEPTH",
  49                   "deepen history of shallow clone"),
  50        OPT_END()
  51};
  52
  53static void unlock_pack(void)
  54{
  55        if (transport)
  56                transport_unlock_pack(transport);
  57}
  58
  59static void unlock_pack_on_signal(int signo)
  60{
  61        unlock_pack();
  62        signal(SIGINT, SIG_DFL);
  63        raise(signo);
  64}
  65
  66static void add_merge_config(struct ref **head,
  67                           const struct ref *remote_refs,
  68                           struct branch *branch,
  69                           struct ref ***tail)
  70{
  71        int i;
  72
  73        for (i = 0; i < branch->merge_nr; i++) {
  74                struct ref *rm, **old_tail = *tail;
  75                struct refspec refspec;
  76
  77                for (rm = *head; rm; rm = rm->next) {
  78                        if (branch_merge_matches(branch, i, rm->name)) {
  79                                rm->merge = 1;
  80                                break;
  81                        }
  82                }
  83                if (rm)
  84                        continue;
  85
  86                /*
  87                 * Not fetched to a tracking branch?  We need to fetch
  88                 * it anyway to allow this branch's "branch.$name.merge"
  89                 * to be honored by git-pull, but we do not have to
  90                 * fail if branch.$name.merge is misconfigured to point
  91                 * at a nonexisting branch.  If we were indeed called by
  92                 * git-pull, it will notice the misconfiguration because
  93                 * there is no entry in the resulting FETCH_HEAD marked
  94                 * for merging.
  95                 */
  96                refspec.src = branch->merge[i]->src;
  97                refspec.dst = NULL;
  98                refspec.pattern = 0;
  99                refspec.force = 0;
 100                get_fetch_map(remote_refs, &refspec, tail, 1);
 101                for (rm = *old_tail; rm; rm = rm->next)
 102                        rm->merge = 1;
 103        }
 104}
 105
 106static void find_non_local_tags(struct transport *transport,
 107                        struct ref **head,
 108                        struct ref ***tail);
 109
 110static struct ref *get_ref_map(struct transport *transport,
 111                               struct refspec *refs, int ref_count, int tags,
 112                               int *autotags)
 113{
 114        int i;
 115        struct ref *rm;
 116        struct ref *ref_map = NULL;
 117        struct ref **tail = &ref_map;
 118
 119        const struct ref *remote_refs = transport_get_remote_refs(transport);
 120
 121        if (ref_count || tags == TAGS_SET) {
 122                for (i = 0; i < ref_count; i++) {
 123                        get_fetch_map(remote_refs, &refs[i], &tail, 0);
 124                        if (refs[i].dst && refs[i].dst[0])
 125                                *autotags = 1;
 126                }
 127                /* Merge everything on the command line, but not --tags */
 128                for (rm = ref_map; rm; rm = rm->next)
 129                        rm->merge = 1;
 130                if (tags == TAGS_SET) {
 131                        struct refspec refspec;
 132                        refspec.src = "refs/tags/";
 133                        refspec.dst = "refs/tags/";
 134                        refspec.pattern = 1;
 135                        refspec.force = 0;
 136                        get_fetch_map(remote_refs, &refspec, &tail, 0);
 137                }
 138        } else {
 139                /* Use the defaults */
 140                struct remote *remote = transport->remote;
 141                struct branch *branch = branch_get(NULL);
 142                int has_merge = branch_has_merge_config(branch);
 143                if (remote && (remote->fetch_refspec_nr || has_merge)) {
 144                        for (i = 0; i < remote->fetch_refspec_nr; i++) {
 145                                get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
 146                                if (remote->fetch[i].dst &&
 147                                    remote->fetch[i].dst[0])
 148                                        *autotags = 1;
 149                                if (!i && !has_merge && ref_map &&
 150                                    !remote->fetch[0].pattern)
 151                                        ref_map->merge = 1;
 152                        }
 153                        /*
 154                         * if the remote we're fetching from is the same
 155                         * as given in branch.<name>.remote, we add the
 156                         * ref given in branch.<name>.merge, too.
 157                         */
 158                        if (has_merge &&
 159                            !strcmp(branch->remote_name, remote->name))
 160                                add_merge_config(&ref_map, remote_refs, branch, &tail);
 161                } else {
 162                        ref_map = get_remote_ref(remote_refs, "HEAD");
 163                        if (!ref_map)
 164                                die("Couldn't find remote ref HEAD");
 165                        ref_map->merge = 1;
 166                        tail = &ref_map->next;
 167                }
 168        }
 169        if (tags == TAGS_DEFAULT && *autotags)
 170                find_non_local_tags(transport, &ref_map, &tail);
 171        ref_remove_duplicates(ref_map);
 172
 173        return ref_map;
 174}
 175
 176static int s_update_ref(const char *action,
 177                        struct ref *ref,
 178                        int check_old)
 179{
 180        char msg[1024];
 181        char *rla = getenv("GIT_REFLOG_ACTION");
 182        static struct ref_lock *lock;
 183
 184        if (!rla)
 185                rla = default_rla.buf;
 186        snprintf(msg, sizeof(msg), "%s: %s", rla, action);
 187        lock = lock_any_ref_for_update(ref->name,
 188                                       check_old ? ref->old_sha1 : NULL, 0);
 189        if (!lock)
 190                return 1;
 191        if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
 192                return 1;
 193        return 0;
 194}
 195
 196#define SUMMARY_WIDTH (2 * DEFAULT_ABBREV + 3)
 197#define REFCOL_WIDTH  10
 198
 199static int update_local_ref(struct ref *ref,
 200                            const char *remote,
 201                            int verbose,
 202                            char *display)
 203{
 204        struct commit *current = NULL, *updated;
 205        enum object_type type;
 206        struct branch *current_branch = branch_get(NULL);
 207        const char *pretty_ref = ref->name + (
 208                !prefixcmp(ref->name, "refs/heads/") ? 11 :
 209                !prefixcmp(ref->name, "refs/tags/") ? 10 :
 210                !prefixcmp(ref->name, "refs/remotes/") ? 13 :
 211                0);
 212
 213        *display = 0;
 214        type = sha1_object_info(ref->new_sha1, NULL);
 215        if (type < 0)
 216                die("object %s not found", sha1_to_hex(ref->new_sha1));
 217
 218        if (!*ref->name) {
 219                /* Not storing */
 220                if (verbose)
 221                        sprintf(display, "* branch %s -> FETCH_HEAD", remote);
 222                return 0;
 223        }
 224
 225        if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
 226                if (verbose)
 227                        sprintf(display, "= %-*s %-*s -> %s", SUMMARY_WIDTH,
 228                                "[up to date]", REFCOL_WIDTH, remote,
 229                                pretty_ref);
 230                return 0;
 231        }
 232
 233        if (current_branch &&
 234            !strcmp(ref->name, current_branch->name) &&
 235            !(update_head_ok || is_bare_repository()) &&
 236            !is_null_sha1(ref->old_sha1)) {
 237                /*
 238                 * If this is the head, and it's not okay to update
 239                 * the head, and the old value of the head isn't empty...
 240                 */
 241                sprintf(display, "! %-*s %-*s -> %s  (can't fetch in current branch)",
 242                        SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
 243                        pretty_ref);
 244                return 1;
 245        }
 246
 247        if (!is_null_sha1(ref->old_sha1) &&
 248            !prefixcmp(ref->name, "refs/tags/")) {
 249                sprintf(display, "- %-*s %-*s -> %s",
 250                        SUMMARY_WIDTH, "[tag update]", REFCOL_WIDTH, remote,
 251                        pretty_ref);
 252                return s_update_ref("updating tag", ref, 0);
 253        }
 254
 255        current = lookup_commit_reference_gently(ref->old_sha1, 1);
 256        updated = lookup_commit_reference_gently(ref->new_sha1, 1);
 257        if (!current || !updated) {
 258                const char *msg;
 259                const char *what;
 260                if (!strncmp(ref->name, "refs/tags/", 10)) {
 261                        msg = "storing tag";
 262                        what = "[new tag]";
 263                }
 264                else {
 265                        msg = "storing head";
 266                        what = "[new branch]";
 267                }
 268
 269                sprintf(display, "* %-*s %-*s -> %s", SUMMARY_WIDTH, what,
 270                        REFCOL_WIDTH, remote, pretty_ref);
 271                return s_update_ref(msg, ref, 0);
 272        }
 273
 274        if (in_merge_bases(current, &updated, 1)) {
 275                char quickref[83];
 276                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 277                strcat(quickref, "..");
 278                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 279                sprintf(display, "  %-*s %-*s -> %s", SUMMARY_WIDTH, quickref,
 280                        REFCOL_WIDTH, remote, pretty_ref);
 281                return s_update_ref("fast forward", ref, 1);
 282        } else if (force || ref->force) {
 283                char quickref[84];
 284                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 285                strcat(quickref, "...");
 286                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 287                sprintf(display, "+ %-*s %-*s -> %s  (forced update)",
 288                        SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote, pretty_ref);
 289                return s_update_ref("forced-update", ref, 1);
 290        } else {
 291                sprintf(display, "! %-*s %-*s -> %s  (non fast forward)",
 292                        SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
 293                        pretty_ref);
 294                return 1;
 295        }
 296}
 297
 298static int store_updated_refs(const char *url, struct ref *ref_map)
 299{
 300        FILE *fp;
 301        struct commit *commit;
 302        int url_len, i, note_len, shown_url = 0;
 303        char note[1024];
 304        const char *what, *kind;
 305        struct ref *rm;
 306        char *filename = git_path("FETCH_HEAD");
 307
 308        fp = fopen(filename, "a");
 309        if (!fp)
 310                return error("cannot open %s: %s\n", filename, strerror(errno));
 311        for (rm = ref_map; rm; rm = rm->next) {
 312                struct ref *ref = NULL;
 313
 314                if (rm->peer_ref) {
 315                        ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
 316                        strcpy(ref->name, rm->peer_ref->name);
 317                        hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
 318                        hashcpy(ref->new_sha1, rm->old_sha1);
 319                        ref->force = rm->peer_ref->force;
 320                }
 321
 322                commit = lookup_commit_reference_gently(rm->old_sha1, 1);
 323                if (!commit)
 324                        rm->merge = 0;
 325
 326                if (!strcmp(rm->name, "HEAD")) {
 327                        kind = "";
 328                        what = "";
 329                }
 330                else if (!prefixcmp(rm->name, "refs/heads/")) {
 331                        kind = "branch";
 332                        what = rm->name + 11;
 333                }
 334                else if (!prefixcmp(rm->name, "refs/tags/")) {
 335                        kind = "tag";
 336                        what = rm->name + 10;
 337                }
 338                else if (!prefixcmp(rm->name, "refs/remotes/")) {
 339                        kind = "remote branch";
 340                        what = rm->name + 13;
 341                }
 342                else {
 343                        kind = "";
 344                        what = rm->name;
 345                }
 346
 347                url_len = strlen(url);
 348                for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
 349                        ;
 350                url_len = i + 1;
 351                if (4 < i && !strncmp(".git", url + i - 3, 4))
 352                        url_len = i - 3;
 353
 354                note_len = 0;
 355                if (*what) {
 356                        if (*kind)
 357                                note_len += sprintf(note + note_len, "%s ",
 358                                                    kind);
 359                        note_len += sprintf(note + note_len, "'%s' of ", what);
 360                }
 361                note_len += sprintf(note + note_len, "%.*s", url_len, url);
 362                fprintf(fp, "%s\t%s\t%s\n",
 363                        sha1_to_hex(commit ? commit->object.sha1 :
 364                                    rm->old_sha1),
 365                        rm->merge ? "" : "not-for-merge",
 366                        note);
 367
 368                if (ref) {
 369                        update_local_ref(ref, what, verbose, note);
 370                        if (*note) {
 371                                if (!shown_url) {
 372                                        fprintf(stderr, "From %.*s\n",
 373                                                        url_len, url);
 374                                        shown_url = 1;
 375                                }
 376                                fprintf(stderr, " %s\n", note);
 377                        }
 378                }
 379        }
 380        fclose(fp);
 381        return 0;
 382}
 383
 384/*
 385 * We would want to bypass the object transfer altogether if
 386 * everything we are going to fetch already exists and connected
 387 * locally.
 388 *
 389 * The refs we are going to fetch are in to_fetch (nr_heads in
 390 * total).  If running
 391 *
 392 *  $ git-rev-list --objects to_fetch[0] to_fetch[1] ... --not --all
 393 *
 394 * does not error out, that means everything reachable from the
 395 * refs we are going to fetch exists and is connected to some of
 396 * our existing refs.
 397 */
 398static int quickfetch(struct ref *ref_map)
 399{
 400        struct child_process revlist;
 401        struct ref *ref;
 402        char **argv;
 403        int i, err;
 404
 405        /*
 406         * If we are deepening a shallow clone we already have these
 407         * objects reachable.  Running rev-list here will return with
 408         * a good (0) exit status and we'll bypass the fetch that we
 409         * really need to perform.  Claiming failure now will ensure
 410         * we perform the network exchange to deepen our history.
 411         */
 412        if (depth)
 413                return -1;
 414
 415        for (i = 0, ref = ref_map; ref; ref = ref->next)
 416                i++;
 417        if (!i)
 418                return 0;
 419
 420        argv = xmalloc(sizeof(*argv) * (i + 6));
 421        i = 0;
 422        argv[i++] = xstrdup("rev-list");
 423        argv[i++] = xstrdup("--quiet");
 424        argv[i++] = xstrdup("--objects");
 425        for (ref = ref_map; ref; ref = ref->next)
 426                argv[i++] = xstrdup(sha1_to_hex(ref->old_sha1));
 427        argv[i++] = xstrdup("--not");
 428        argv[i++] = xstrdup("--all");
 429        argv[i++] = NULL;
 430
 431        memset(&revlist, 0, sizeof(revlist));
 432        revlist.argv = (const char**)argv;
 433        revlist.git_cmd = 1;
 434        revlist.no_stdin = 1;
 435        revlist.no_stdout = 1;
 436        revlist.no_stderr = 1;
 437        err = run_command(&revlist);
 438
 439        for (i = 0; argv[i]; i++)
 440                free(argv[i]);
 441        free(argv);
 442        return err;
 443}
 444
 445static int fetch_refs(struct transport *transport, struct ref *ref_map)
 446{
 447        int ret = quickfetch(ref_map);
 448        if (ret)
 449                ret = transport_fetch_refs(transport, ref_map);
 450        if (!ret)
 451                ret |= store_updated_refs(transport->url, ref_map);
 452        transport_unlock_pack(transport);
 453        return ret;
 454}
 455
 456static int add_existing(const char *refname, const unsigned char *sha1,
 457                        int flag, void *cbdata)
 458{
 459        struct path_list *list = (struct path_list *)cbdata;
 460        path_list_insert(refname, list);
 461        return 0;
 462}
 463
 464static int will_fetch(struct ref **head, const unsigned char *sha1)
 465{
 466        struct ref *rm = *head;
 467        while (rm) {
 468                if (!hashcmp(rm->old_sha1, sha1))
 469                        return 1;
 470                rm = rm->next;
 471        }
 472        return 0;
 473}
 474
 475static void find_non_local_tags(struct transport *transport,
 476                        struct ref **head,
 477                        struct ref ***tail)
 478{
 479        struct path_list existing_refs = { NULL, 0, 0, 0 };
 480        struct path_list new_refs = { NULL, 0, 0, 1 };
 481        char *ref_name;
 482        int ref_name_len;
 483        const unsigned char *ref_sha1;
 484        const struct ref *tag_ref;
 485        struct ref *rm = NULL;
 486        const struct ref *ref;
 487
 488        for_each_ref(add_existing, &existing_refs);
 489        for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
 490                if (prefixcmp(ref->name, "refs/tags"))
 491                        continue;
 492
 493                ref_name = xstrdup(ref->name);
 494                ref_name_len = strlen(ref_name);
 495                ref_sha1 = ref->old_sha1;
 496
 497                if (!strcmp(ref_name + ref_name_len - 3, "^{}")) {
 498                        ref_name[ref_name_len - 3] = 0;
 499                        tag_ref = transport_get_remote_refs(transport);
 500                        while (tag_ref) {
 501                                if (!strcmp(tag_ref->name, ref_name)) {
 502                                        ref_sha1 = tag_ref->old_sha1;
 503                                        break;
 504                                }
 505                                tag_ref = tag_ref->next;
 506                        }
 507                }
 508
 509                if (!path_list_has_path(&existing_refs, ref_name) &&
 510                    !path_list_has_path(&new_refs, ref_name) &&
 511                    (has_sha1_file(ref->old_sha1) ||
 512                     will_fetch(head, ref->old_sha1))) {
 513                        path_list_insert(ref_name, &new_refs);
 514
 515                        rm = alloc_ref(strlen(ref_name) + 1);
 516                        strcpy(rm->name, ref_name);
 517                        rm->peer_ref = alloc_ref(strlen(ref_name) + 1);
 518                        strcpy(rm->peer_ref->name, ref_name);
 519                        hashcpy(rm->old_sha1, ref_sha1);
 520
 521                        **tail = rm;
 522                        *tail = &rm->next;
 523                }
 524                free(ref_name);
 525        }
 526        path_list_clear(&existing_refs, 0);
 527        path_list_clear(&new_refs, 0);
 528}
 529
 530static int do_fetch(struct transport *transport,
 531                    struct refspec *refs, int ref_count)
 532{
 533        struct ref *ref_map;
 534        struct ref *rm;
 535        int autotags = (transport->remote->fetch_tags == 1);
 536        if (transport->remote->fetch_tags == 2 && tags != TAGS_UNSET)
 537                tags = TAGS_SET;
 538        if (transport->remote->fetch_tags == -1)
 539                tags = TAGS_UNSET;
 540
 541        if (!transport->get_refs_list || !transport->fetch)
 542                die("Don't know how to fetch from %s", transport->url);
 543
 544        /* if not appending, truncate FETCH_HEAD */
 545        if (!append) {
 546                char *filename = git_path("FETCH_HEAD");
 547                FILE *fp = fopen(filename, "w");
 548                if (!fp)
 549                        return error("cannot open %s: %s\n", filename, strerror(errno));
 550                fclose(fp);
 551        }
 552
 553        ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
 554
 555        for (rm = ref_map; rm; rm = rm->next) {
 556                if (rm->peer_ref)
 557                        read_ref(rm->peer_ref->name, rm->peer_ref->old_sha1);
 558        }
 559
 560        if (tags == TAGS_DEFAULT && autotags)
 561                transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 562        if (fetch_refs(transport, ref_map)) {
 563                free_refs(ref_map);
 564                return 1;
 565        }
 566        free_refs(ref_map);
 567
 568        /* if neither --no-tags nor --tags was specified, do automated tag
 569         * following ... */
 570        if (tags == TAGS_DEFAULT && autotags) {
 571                struct ref **tail = &ref_map;
 572                ref_map = NULL;
 573                find_non_local_tags(transport, &ref_map, &tail);
 574                if (ref_map) {
 575                        transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, NULL);
 576                        transport_set_option(transport, TRANS_OPT_DEPTH, "0");
 577                        fetch_refs(transport, ref_map);
 578                }
 579                free_refs(ref_map);
 580        }
 581
 582        transport_disconnect(transport);
 583
 584        return 0;
 585}
 586
 587static void set_option(const char *name, const char *value)
 588{
 589        int r = transport_set_option(transport, name, value);
 590        if (r < 0)
 591                die("Option \"%s\" value \"%s\" is not valid for %s\n",
 592                        name, value, transport->url);
 593        if (r > 0)
 594                warning("Option \"%s\" is ignored for %s\n",
 595                        name, transport->url);
 596}
 597
 598int cmd_fetch(int argc, const char **argv, const char *prefix)
 599{
 600        struct remote *remote;
 601        int i;
 602        static const char **refs = NULL;
 603        int ref_nr = 0;
 604
 605        /* Record the command line for the reflog */
 606        strbuf_addstr(&default_rla, "fetch");
 607        for (i = 1; i < argc; i++)
 608                strbuf_addf(&default_rla, " %s", argv[i]);
 609
 610        argc = parse_options(argc, argv,
 611                             builtin_fetch_options, builtin_fetch_usage, 0);
 612
 613        if (argc == 0)
 614                remote = remote_get(NULL);
 615        else
 616                remote = remote_get(argv[0]);
 617
 618        transport = transport_get(remote, remote->url[0]);
 619        if (verbose >= 2)
 620                transport->verbose = 1;
 621        if (quiet)
 622                transport->verbose = -1;
 623        if (upload_pack)
 624                set_option(TRANS_OPT_UPLOADPACK, upload_pack);
 625        if (keep)
 626                set_option(TRANS_OPT_KEEP, "yes");
 627        if (depth)
 628                set_option(TRANS_OPT_DEPTH, depth);
 629
 630        if (!transport->url)
 631                die("Where do you want to fetch from today?");
 632
 633        if (argc > 1) {
 634                int j = 0;
 635                refs = xcalloc(argc + 1, sizeof(const char *));
 636                for (i = 1; i < argc; i++) {
 637                        if (!strcmp(argv[i], "tag")) {
 638                                char *ref;
 639                                i++;
 640                                ref = xmalloc(strlen(argv[i]) * 2 + 22);
 641                                strcpy(ref, "refs/tags/");
 642                                strcat(ref, argv[i]);
 643                                strcat(ref, ":refs/tags/");
 644                                strcat(ref, argv[i]);
 645                                refs[j++] = ref;
 646                        } else
 647                                refs[j++] = argv[i];
 648                }
 649                refs[j] = NULL;
 650                ref_nr = j;
 651        }
 652
 653        signal(SIGINT, unlock_pack_on_signal);
 654        atexit(unlock_pack);
 655        return do_fetch(transport,
 656                        parse_fetch_refspec(ref_nr, refs), ref_nr);
 657}