builtin / fetch.con commit Merge branch 'jk/cat-file-batch-optim' (c7eb614)
   1/*
   2 * "git fetch"
   3 */
   4#include "cache.h"
   5#include "refs.h"
   6#include "commit.h"
   7#include "builtin.h"
   8#include "string-list.h"
   9#include "remote.h"
  10#include "transport.h"
  11#include "run-command.h"
  12#include "parse-options.h"
  13#include "sigchain.h"
  14#include "transport.h"
  15#include "submodule.h"
  16#include "connected.h"
  17#include "argv-array.h"
  18
  19static const char * const builtin_fetch_usage[] = {
  20        N_("git fetch [<options>] [<repository> [<refspec>...]]"),
  21        N_("git fetch [<options>] <group>"),
  22        N_("git fetch --multiple [<options>] [(<repository> | <group>)...]"),
  23        N_("git fetch --all [<options>]"),
  24        NULL
  25};
  26
  27enum {
  28        TAGS_UNSET = 0,
  29        TAGS_DEFAULT = 1,
  30        TAGS_SET = 2
  31};
  32
  33static int all, append, dry_run, force, keep, multiple, prune, update_head_ok, verbosity;
  34static int progress = -1, recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
  35static int tags = TAGS_DEFAULT, unshallow;
  36static const char *depth;
  37static const char *upload_pack;
  38static struct strbuf default_rla = STRBUF_INIT;
  39static struct transport *transport;
  40static const char *submodule_prefix = "";
  41static const char *recurse_submodules_default;
  42
  43static int option_parse_recurse_submodules(const struct option *opt,
  44                                   const char *arg, int unset)
  45{
  46        if (unset) {
  47                recurse_submodules = RECURSE_SUBMODULES_OFF;
  48        } else {
  49                if (arg)
  50                        recurse_submodules = parse_fetch_recurse_submodules_arg(opt->long_name, arg);
  51                else
  52                        recurse_submodules = RECURSE_SUBMODULES_ON;
  53        }
  54        return 0;
  55}
  56
  57static struct option builtin_fetch_options[] = {
  58        OPT__VERBOSITY(&verbosity),
  59        OPT_BOOLEAN(0, "all", &all,
  60                    N_("fetch from all remotes")),
  61        OPT_BOOLEAN('a', "append", &append,
  62                    N_("append to .git/FETCH_HEAD instead of overwriting")),
  63        OPT_STRING(0, "upload-pack", &upload_pack, N_("path"),
  64                   N_("path to upload pack on remote end")),
  65        OPT__FORCE(&force, N_("force overwrite of local branch")),
  66        OPT_BOOLEAN('m', "multiple", &multiple,
  67                    N_("fetch from multiple remotes")),
  68        OPT_SET_INT('t', "tags", &tags,
  69                    N_("fetch all tags and associated objects"), TAGS_SET),
  70        OPT_SET_INT('n', NULL, &tags,
  71                    N_("do not fetch all tags (--no-tags)"), TAGS_UNSET),
  72        OPT_BOOLEAN('p', "prune", &prune,
  73                    N_("prune remote-tracking branches no longer on remote")),
  74        { OPTION_CALLBACK, 0, "recurse-submodules", NULL, N_("on-demand"),
  75                    N_("control recursive fetching of submodules"),
  76                    PARSE_OPT_OPTARG, option_parse_recurse_submodules },
  77        OPT_BOOLEAN(0, "dry-run", &dry_run,
  78                    N_("dry run")),
  79        OPT_BOOLEAN('k', "keep", &keep, N_("keep downloaded pack")),
  80        OPT_BOOLEAN('u', "update-head-ok", &update_head_ok,
  81                    N_("allow updating of HEAD ref")),
  82        OPT_BOOL(0, "progress", &progress, N_("force progress reporting")),
  83        OPT_STRING(0, "depth", &depth, N_("depth"),
  84                   N_("deepen history of shallow clone")),
  85        { OPTION_SET_INT, 0, "unshallow", &unshallow, NULL,
  86                   N_("convert to a complete repository"),
  87                   PARSE_OPT_NONEG | PARSE_OPT_NOARG, NULL, 1 },
  88        { OPTION_STRING, 0, "submodule-prefix", &submodule_prefix, N_("dir"),
  89                   N_("prepend this to submodule path output"), PARSE_OPT_HIDDEN },
  90        { OPTION_STRING, 0, "recurse-submodules-default",
  91                   &recurse_submodules_default, NULL,
  92                   N_("default mode for recursion"), PARSE_OPT_HIDDEN },
  93        OPT_END()
  94};
  95
  96static void unlock_pack(void)
  97{
  98        if (transport)
  99                transport_unlock_pack(transport);
 100}
 101
 102static void unlock_pack_on_signal(int signo)
 103{
 104        unlock_pack();
 105        sigchain_pop(signo);
 106        raise(signo);
 107}
 108
 109static void add_merge_config(struct ref **head,
 110                           const struct ref *remote_refs,
 111                           struct branch *branch,
 112                           struct ref ***tail)
 113{
 114        int i;
 115
 116        for (i = 0; i < branch->merge_nr; i++) {
 117                struct ref *rm, **old_tail = *tail;
 118                struct refspec refspec;
 119
 120                for (rm = *head; rm; rm = rm->next) {
 121                        if (branch_merge_matches(branch, i, rm->name)) {
 122                                rm->fetch_head_status = FETCH_HEAD_MERGE;
 123                                break;
 124                        }
 125                }
 126                if (rm)
 127                        continue;
 128
 129                /*
 130                 * Not fetched to a remote-tracking branch?  We need to fetch
 131                 * it anyway to allow this branch's "branch.$name.merge"
 132                 * to be honored by 'git pull', but we do not have to
 133                 * fail if branch.$name.merge is misconfigured to point
 134                 * at a nonexisting branch.  If we were indeed called by
 135                 * 'git pull', it will notice the misconfiguration because
 136                 * there is no entry in the resulting FETCH_HEAD marked
 137                 * for merging.
 138                 */
 139                memset(&refspec, 0, sizeof(refspec));
 140                refspec.src = branch->merge[i]->src;
 141                get_fetch_map(remote_refs, &refspec, tail, 1);
 142                for (rm = *old_tail; rm; rm = rm->next)
 143                        rm->fetch_head_status = FETCH_HEAD_MERGE;
 144        }
 145}
 146
 147static void find_non_local_tags(struct transport *transport,
 148                        struct ref **head,
 149                        struct ref ***tail);
 150
 151static struct ref *get_ref_map(struct transport *transport,
 152                               struct refspec *refs, int ref_count, int tags,
 153                               int *autotags)
 154{
 155        int i;
 156        struct ref *rm;
 157        struct ref *ref_map = NULL;
 158        struct ref **tail = &ref_map;
 159
 160        const struct ref *remote_refs = transport_get_remote_refs(transport);
 161
 162        if (ref_count || tags == TAGS_SET) {
 163                struct ref **old_tail;
 164
 165                for (i = 0; i < ref_count; i++) {
 166                        get_fetch_map(remote_refs, &refs[i], &tail, 0);
 167                        if (refs[i].dst && refs[i].dst[0])
 168                                *autotags = 1;
 169                }
 170                /* Merge everything on the command line, but not --tags */
 171                for (rm = ref_map; rm; rm = rm->next)
 172                        rm->fetch_head_status = FETCH_HEAD_MERGE;
 173                if (tags == TAGS_SET)
 174                        get_fetch_map(remote_refs, tag_refspec, &tail, 0);
 175
 176                /*
 177                 * For any refs that we happen to be fetching via command-line
 178                 * arguments, take the opportunity to update their configured
 179                 * counterparts. However, we do not want to mention these
 180                 * entries in FETCH_HEAD at all, as they would simply be
 181                 * duplicates of existing entries.
 182                 */
 183                old_tail = tail;
 184                for (i = 0; i < transport->remote->fetch_refspec_nr; i++)
 185                        get_fetch_map(ref_map, &transport->remote->fetch[i],
 186                                      &tail, 1);
 187                for (rm = *old_tail; rm; rm = rm->next)
 188                        rm->fetch_head_status = FETCH_HEAD_IGNORE;
 189        } else {
 190                /* Use the defaults */
 191                struct remote *remote = transport->remote;
 192                struct branch *branch = branch_get(NULL);
 193                int has_merge = branch_has_merge_config(branch);
 194                if (remote &&
 195                    (remote->fetch_refspec_nr ||
 196                     /* Note: has_merge implies non-NULL branch->remote_name */
 197                     (has_merge && !strcmp(branch->remote_name, remote->name)))) {
 198                        for (i = 0; i < remote->fetch_refspec_nr; i++) {
 199                                get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
 200                                if (remote->fetch[i].dst &&
 201                                    remote->fetch[i].dst[0])
 202                                        *autotags = 1;
 203                                if (!i && !has_merge && ref_map &&
 204                                    !remote->fetch[0].pattern)
 205                                        ref_map->fetch_head_status = FETCH_HEAD_MERGE;
 206                        }
 207                        /*
 208                         * if the remote we're fetching from is the same
 209                         * as given in branch.<name>.remote, we add the
 210                         * ref given in branch.<name>.merge, too.
 211                         *
 212                         * Note: has_merge implies non-NULL branch->remote_name
 213                         */
 214                        if (has_merge &&
 215                            !strcmp(branch->remote_name, remote->name))
 216                                add_merge_config(&ref_map, remote_refs, branch, &tail);
 217                } else {
 218                        ref_map = get_remote_ref(remote_refs, "HEAD");
 219                        if (!ref_map)
 220                                die(_("Couldn't find remote ref HEAD"));
 221                        ref_map->fetch_head_status = FETCH_HEAD_MERGE;
 222                        tail = &ref_map->next;
 223                }
 224        }
 225        if (tags == TAGS_DEFAULT && *autotags)
 226                find_non_local_tags(transport, &ref_map, &tail);
 227        ref_remove_duplicates(ref_map);
 228
 229        return ref_map;
 230}
 231
 232#define STORE_REF_ERROR_OTHER 1
 233#define STORE_REF_ERROR_DF_CONFLICT 2
 234
 235static int s_update_ref(const char *action,
 236                        struct ref *ref,
 237                        int check_old)
 238{
 239        char msg[1024];
 240        char *rla = getenv("GIT_REFLOG_ACTION");
 241        static struct ref_lock *lock;
 242
 243        if (dry_run)
 244                return 0;
 245        if (!rla)
 246                rla = default_rla.buf;
 247        snprintf(msg, sizeof(msg), "%s: %s", rla, action);
 248        lock = lock_any_ref_for_update(ref->name,
 249                                       check_old ? ref->old_sha1 : NULL, 0);
 250        if (!lock)
 251                return errno == ENOTDIR ? STORE_REF_ERROR_DF_CONFLICT :
 252                                          STORE_REF_ERROR_OTHER;
 253        if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
 254                return errno == ENOTDIR ? STORE_REF_ERROR_DF_CONFLICT :
 255                                          STORE_REF_ERROR_OTHER;
 256        return 0;
 257}
 258
 259#define REFCOL_WIDTH  10
 260
 261static int update_local_ref(struct ref *ref,
 262                            const char *remote,
 263                            const struct ref *remote_ref,
 264                            struct strbuf *display)
 265{
 266        struct commit *current = NULL, *updated;
 267        enum object_type type;
 268        struct branch *current_branch = branch_get(NULL);
 269        const char *pretty_ref = prettify_refname(ref->name);
 270
 271        type = sha1_object_info(ref->new_sha1, NULL);
 272        if (type < 0)
 273                die(_("object %s not found"), sha1_to_hex(ref->new_sha1));
 274
 275        if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
 276                if (verbosity > 0)
 277                        strbuf_addf(display, "= %-*s %-*s -> %s",
 278                                    TRANSPORT_SUMMARY(_("[up to date]")),
 279                                    REFCOL_WIDTH, remote, pretty_ref);
 280                return 0;
 281        }
 282
 283        if (current_branch &&
 284            !strcmp(ref->name, current_branch->name) &&
 285            !(update_head_ok || is_bare_repository()) &&
 286            !is_null_sha1(ref->old_sha1)) {
 287                /*
 288                 * If this is the head, and it's not okay to update
 289                 * the head, and the old value of the head isn't empty...
 290                 */
 291                strbuf_addf(display,
 292                            _("! %-*s %-*s -> %s  (can't fetch in current branch)"),
 293                            TRANSPORT_SUMMARY(_("[rejected]")),
 294                            REFCOL_WIDTH, remote, pretty_ref);
 295                return 1;
 296        }
 297
 298        if (!is_null_sha1(ref->old_sha1) &&
 299            !prefixcmp(ref->name, "refs/tags/")) {
 300                int r;
 301                r = s_update_ref("updating tag", ref, 0);
 302                strbuf_addf(display, "%c %-*s %-*s -> %s%s",
 303                            r ? '!' : '-',
 304                            TRANSPORT_SUMMARY(_("[tag update]")),
 305                            REFCOL_WIDTH, remote, pretty_ref,
 306                            r ? _("  (unable to update local ref)") : "");
 307                return r;
 308        }
 309
 310        current = lookup_commit_reference_gently(ref->old_sha1, 1);
 311        updated = lookup_commit_reference_gently(ref->new_sha1, 1);
 312        if (!current || !updated) {
 313                const char *msg;
 314                const char *what;
 315                int r;
 316                /*
 317                 * Nicely describe the new ref we're fetching.
 318                 * Base this on the remote's ref name, as it's
 319                 * more likely to follow a standard layout.
 320                 */
 321                const char *name = remote_ref ? remote_ref->name : "";
 322                if (!prefixcmp(name, "refs/tags/")) {
 323                        msg = "storing tag";
 324                        what = _("[new tag]");
 325                } else if (!prefixcmp(name, "refs/heads/")) {
 326                        msg = "storing head";
 327                        what = _("[new branch]");
 328                } else {
 329                        msg = "storing ref";
 330                        what = _("[new ref]");
 331                }
 332
 333                if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
 334                    (recurse_submodules != RECURSE_SUBMODULES_ON))
 335                        check_for_new_submodule_commits(ref->new_sha1);
 336                r = s_update_ref(msg, ref, 0);
 337                strbuf_addf(display, "%c %-*s %-*s -> %s%s",
 338                            r ? '!' : '*',
 339                            TRANSPORT_SUMMARY(what),
 340                            REFCOL_WIDTH, remote, pretty_ref,
 341                            r ? _("  (unable to update local ref)") : "");
 342                return r;
 343        }
 344
 345        if (in_merge_bases(current, updated)) {
 346                char quickref[83];
 347                int r;
 348                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 349                strcat(quickref, "..");
 350                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 351                if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
 352                    (recurse_submodules != RECURSE_SUBMODULES_ON))
 353                        check_for_new_submodule_commits(ref->new_sha1);
 354                r = s_update_ref("fast-forward", ref, 1);
 355                strbuf_addf(display, "%c %-*s %-*s -> %s%s",
 356                            r ? '!' : ' ',
 357                            TRANSPORT_SUMMARY_WIDTH, quickref,
 358                            REFCOL_WIDTH, remote, pretty_ref,
 359                            r ? _("  (unable to update local ref)") : "");
 360                return r;
 361        } else if (force || ref->force) {
 362                char quickref[84];
 363                int r;
 364                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 365                strcat(quickref, "...");
 366                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 367                if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
 368                    (recurse_submodules != RECURSE_SUBMODULES_ON))
 369                        check_for_new_submodule_commits(ref->new_sha1);
 370                r = s_update_ref("forced-update", ref, 1);
 371                strbuf_addf(display, "%c %-*s %-*s -> %s  (%s)",
 372                            r ? '!' : '+',
 373                            TRANSPORT_SUMMARY_WIDTH, quickref,
 374                            REFCOL_WIDTH, remote, pretty_ref,
 375                            r ? _("unable to update local ref") : _("forced update"));
 376                return r;
 377        } else {
 378                strbuf_addf(display, "! %-*s %-*s -> %s  %s",
 379                            TRANSPORT_SUMMARY(_("[rejected]")),
 380                            REFCOL_WIDTH, remote, pretty_ref,
 381                            _("(non-fast-forward)"));
 382                return 1;
 383        }
 384}
 385
 386static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
 387{
 388        struct ref **rm = cb_data;
 389        struct ref *ref = *rm;
 390
 391        if (!ref)
 392                return -1; /* end of the list */
 393        *rm = ref->next;
 394        hashcpy(sha1, ref->old_sha1);
 395        return 0;
 396}
 397
 398static int store_updated_refs(const char *raw_url, const char *remote_name,
 399                struct ref *ref_map)
 400{
 401        FILE *fp;
 402        struct commit *commit;
 403        int url_len, i, shown_url = 0, rc = 0;
 404        struct strbuf note = STRBUF_INIT;
 405        const char *what, *kind;
 406        struct ref *rm;
 407        char *url, *filename = dry_run ? "/dev/null" : git_path("FETCH_HEAD");
 408        int want_status;
 409
 410        fp = fopen(filename, "a");
 411        if (!fp)
 412                return error(_("cannot open %s: %s\n"), filename, strerror(errno));
 413
 414        if (raw_url)
 415                url = transport_anonymize_url(raw_url);
 416        else
 417                url = xstrdup("foreign");
 418
 419        rm = ref_map;
 420        if (check_everything_connected(iterate_ref_map, 0, &rm)) {
 421                rc = error(_("%s did not send all necessary objects\n"), url);
 422                goto abort;
 423        }
 424
 425        /*
 426         * We do a pass for each fetch_head_status type in their enum order, so
 427         * merged entries are written before not-for-merge. That lets readers
 428         * use FETCH_HEAD as a refname to refer to the ref to be merged.
 429         */
 430        for (want_status = FETCH_HEAD_MERGE;
 431             want_status <= FETCH_HEAD_IGNORE;
 432             want_status++) {
 433                for (rm = ref_map; rm; rm = rm->next) {
 434                        struct ref *ref = NULL;
 435                        const char *merge_status_marker = "";
 436
 437                        commit = lookup_commit_reference_gently(rm->old_sha1, 1);
 438                        if (!commit)
 439                                rm->fetch_head_status = FETCH_HEAD_NOT_FOR_MERGE;
 440
 441                        if (rm->fetch_head_status != want_status)
 442                                continue;
 443
 444                        if (rm->peer_ref) {
 445                                ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
 446                                strcpy(ref->name, rm->peer_ref->name);
 447                                hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
 448                                hashcpy(ref->new_sha1, rm->old_sha1);
 449                                ref->force = rm->peer_ref->force;
 450                        }
 451
 452
 453                        if (!strcmp(rm->name, "HEAD")) {
 454                                kind = "";
 455                                what = "";
 456                        }
 457                        else if (!prefixcmp(rm->name, "refs/heads/")) {
 458                                kind = "branch";
 459                                what = rm->name + 11;
 460                        }
 461                        else if (!prefixcmp(rm->name, "refs/tags/")) {
 462                                kind = "tag";
 463                                what = rm->name + 10;
 464                        }
 465                        else if (!prefixcmp(rm->name, "refs/remotes/")) {
 466                                kind = "remote-tracking branch";
 467                                what = rm->name + 13;
 468                        }
 469                        else {
 470                                kind = "";
 471                                what = rm->name;
 472                        }
 473
 474                        url_len = strlen(url);
 475                        for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
 476                                ;
 477                        url_len = i + 1;
 478                        if (4 < i && !strncmp(".git", url + i - 3, 4))
 479                                url_len = i - 3;
 480
 481                        strbuf_reset(&note);
 482                        if (*what) {
 483                                if (*kind)
 484                                        strbuf_addf(&note, "%s ", kind);
 485                                strbuf_addf(&note, "'%s' of ", what);
 486                        }
 487                        switch (rm->fetch_head_status) {
 488                        case FETCH_HEAD_NOT_FOR_MERGE:
 489                                merge_status_marker = "not-for-merge";
 490                                /* fall-through */
 491                        case FETCH_HEAD_MERGE:
 492                                fprintf(fp, "%s\t%s\t%s",
 493                                        sha1_to_hex(rm->old_sha1),
 494                                        merge_status_marker,
 495                                        note.buf);
 496                                for (i = 0; i < url_len; ++i)
 497                                        if ('\n' == url[i])
 498                                                fputs("\\n", fp);
 499                                        else
 500                                                fputc(url[i], fp);
 501                                fputc('\n', fp);
 502                                break;
 503                        default:
 504                                /* do not write anything to FETCH_HEAD */
 505                                break;
 506                        }
 507
 508                        strbuf_reset(&note);
 509                        if (ref) {
 510                                rc |= update_local_ref(ref, what, rm, &note);
 511                                free(ref);
 512                        } else
 513                                strbuf_addf(&note, "* %-*s %-*s -> FETCH_HEAD",
 514                                            TRANSPORT_SUMMARY_WIDTH,
 515                                            *kind ? kind : "branch",
 516                                            REFCOL_WIDTH,
 517                                            *what ? what : "HEAD");
 518                        if (note.len) {
 519                                if (verbosity >= 0 && !shown_url) {
 520                                        fprintf(stderr, _("From %.*s\n"),
 521                                                        url_len, url);
 522                                        shown_url = 1;
 523                                }
 524                                if (verbosity >= 0)
 525                                        fprintf(stderr, " %s\n", note.buf);
 526                        }
 527                }
 528        }
 529
 530        if (rc & STORE_REF_ERROR_DF_CONFLICT)
 531                error(_("some local refs could not be updated; try running\n"
 532                      " 'git remote prune %s' to remove any old, conflicting "
 533                      "branches"), remote_name);
 534
 535 abort:
 536        strbuf_release(&note);
 537        free(url);
 538        fclose(fp);
 539        return rc;
 540}
 541
 542/*
 543 * We would want to bypass the object transfer altogether if
 544 * everything we are going to fetch already exists and is connected
 545 * locally.
 546 */
 547static int quickfetch(struct ref *ref_map)
 548{
 549        struct ref *rm = ref_map;
 550
 551        /*
 552         * If we are deepening a shallow clone we already have these
 553         * objects reachable.  Running rev-list here will return with
 554         * a good (0) exit status and we'll bypass the fetch that we
 555         * really need to perform.  Claiming failure now will ensure
 556         * we perform the network exchange to deepen our history.
 557         */
 558        if (depth)
 559                return -1;
 560        return check_everything_connected(iterate_ref_map, 1, &rm);
 561}
 562
 563static int fetch_refs(struct transport *transport, struct ref *ref_map)
 564{
 565        int ret = quickfetch(ref_map);
 566        if (ret)
 567                ret = transport_fetch_refs(transport, ref_map);
 568        if (!ret)
 569                ret |= store_updated_refs(transport->url,
 570                                transport->remote->name,
 571                                ref_map);
 572        transport_unlock_pack(transport);
 573        return ret;
 574}
 575
 576static int prune_refs(struct refspec *refs, int ref_count, struct ref *ref_map)
 577{
 578        int result = 0;
 579        struct ref *ref, *stale_refs = get_stale_heads(refs, ref_count, ref_map);
 580        const char *dangling_msg = dry_run
 581                ? _("   (%s will become dangling)")
 582                : _("   (%s has become dangling)");
 583
 584        for (ref = stale_refs; ref; ref = ref->next) {
 585                if (!dry_run)
 586                        result |= delete_ref(ref->name, NULL, 0);
 587                if (verbosity >= 0) {
 588                        fprintf(stderr, " x %-*s %-*s -> %s\n",
 589                                TRANSPORT_SUMMARY(_("[deleted]")),
 590                                REFCOL_WIDTH, _("(none)"), prettify_refname(ref->name));
 591                        warn_dangling_symref(stderr, dangling_msg, ref->name);
 592                }
 593        }
 594        free_refs(stale_refs);
 595        return result;
 596}
 597
 598static int add_existing(const char *refname, const unsigned char *sha1,
 599                        int flag, void *cbdata)
 600{
 601        struct string_list *list = (struct string_list *)cbdata;
 602        struct string_list_item *item = string_list_insert(list, refname);
 603        item->util = xmalloc(20);
 604        hashcpy(item->util, sha1);
 605        return 0;
 606}
 607
 608static int will_fetch(struct ref **head, const unsigned char *sha1)
 609{
 610        struct ref *rm = *head;
 611        while (rm) {
 612                if (!hashcmp(rm->old_sha1, sha1))
 613                        return 1;
 614                rm = rm->next;
 615        }
 616        return 0;
 617}
 618
 619static void find_non_local_tags(struct transport *transport,
 620                        struct ref **head,
 621                        struct ref ***tail)
 622{
 623        struct string_list existing_refs = STRING_LIST_INIT_DUP;
 624        struct string_list remote_refs = STRING_LIST_INIT_NODUP;
 625        const struct ref *ref;
 626        struct string_list_item *item = NULL;
 627
 628        for_each_ref(add_existing, &existing_refs);
 629        for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
 630                if (prefixcmp(ref->name, "refs/tags/"))
 631                        continue;
 632
 633                /*
 634                 * The peeled ref always follows the matching base
 635                 * ref, so if we see a peeled ref that we don't want
 636                 * to fetch then we can mark the ref entry in the list
 637                 * as one to ignore by setting util to NULL.
 638                 */
 639                if (!suffixcmp(ref->name, "^{}")) {
 640                        if (item && !has_sha1_file(ref->old_sha1) &&
 641                            !will_fetch(head, ref->old_sha1) &&
 642                            !has_sha1_file(item->util) &&
 643                            !will_fetch(head, item->util))
 644                                item->util = NULL;
 645                        item = NULL;
 646                        continue;
 647                }
 648
 649                /*
 650                 * If item is non-NULL here, then we previously saw a
 651                 * ref not followed by a peeled reference, so we need
 652                 * to check if it is a lightweight tag that we want to
 653                 * fetch.
 654                 */
 655                if (item && !has_sha1_file(item->util) &&
 656                    !will_fetch(head, item->util))
 657                        item->util = NULL;
 658
 659                item = NULL;
 660
 661                /* skip duplicates and refs that we already have */
 662                if (string_list_has_string(&remote_refs, ref->name) ||
 663                    string_list_has_string(&existing_refs, ref->name))
 664                        continue;
 665
 666                item = string_list_insert(&remote_refs, ref->name);
 667                item->util = (void *)ref->old_sha1;
 668        }
 669        string_list_clear(&existing_refs, 1);
 670
 671        /*
 672         * We may have a final lightweight tag that needs to be
 673         * checked to see if it needs fetching.
 674         */
 675        if (item && !has_sha1_file(item->util) &&
 676            !will_fetch(head, item->util))
 677                item->util = NULL;
 678
 679        /*
 680         * For all the tags in the remote_refs string list,
 681         * add them to the list of refs to be fetched
 682         */
 683        for_each_string_list_item(item, &remote_refs) {
 684                /* Unless we have already decided to ignore this item... */
 685                if (item->util)
 686                {
 687                        struct ref *rm = alloc_ref(item->string);
 688                        rm->peer_ref = alloc_ref(item->string);
 689                        hashcpy(rm->old_sha1, item->util);
 690                        **tail = rm;
 691                        *tail = &rm->next;
 692                }
 693        }
 694
 695        string_list_clear(&remote_refs, 0);
 696}
 697
 698static void check_not_current_branch(struct ref *ref_map)
 699{
 700        struct branch *current_branch = branch_get(NULL);
 701
 702        if (is_bare_repository() || !current_branch)
 703                return;
 704
 705        for (; ref_map; ref_map = ref_map->next)
 706                if (ref_map->peer_ref && !strcmp(current_branch->refname,
 707                                        ref_map->peer_ref->name))
 708                        die(_("Refusing to fetch into current branch %s "
 709                            "of non-bare repository"), current_branch->refname);
 710}
 711
 712static int truncate_fetch_head(void)
 713{
 714        char *filename = git_path("FETCH_HEAD");
 715        FILE *fp = fopen(filename, "w");
 716
 717        if (!fp)
 718                return error(_("cannot open %s: %s\n"), filename, strerror(errno));
 719        fclose(fp);
 720        return 0;
 721}
 722
 723static int do_fetch(struct transport *transport,
 724                    struct refspec *refs, int ref_count)
 725{
 726        struct string_list existing_refs = STRING_LIST_INIT_DUP;
 727        struct ref *ref_map;
 728        struct ref *rm;
 729        int autotags = (transport->remote->fetch_tags == 1);
 730        int retcode = 0;
 731
 732        for_each_ref(add_existing, &existing_refs);
 733
 734        if (tags == TAGS_DEFAULT) {
 735                if (transport->remote->fetch_tags == 2)
 736                        tags = TAGS_SET;
 737                if (transport->remote->fetch_tags == -1)
 738                        tags = TAGS_UNSET;
 739        }
 740
 741        if (!transport->get_refs_list || !transport->fetch)
 742                die(_("Don't know how to fetch from %s"), transport->url);
 743
 744        /* if not appending, truncate FETCH_HEAD */
 745        if (!append && !dry_run) {
 746                retcode = truncate_fetch_head();
 747                if (retcode)
 748                        goto cleanup;
 749        }
 750
 751        ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
 752        if (!update_head_ok)
 753                check_not_current_branch(ref_map);
 754
 755        for (rm = ref_map; rm; rm = rm->next) {
 756                if (rm->peer_ref) {
 757                        struct string_list_item *peer_item =
 758                                string_list_lookup(&existing_refs,
 759                                                   rm->peer_ref->name);
 760                        if (peer_item)
 761                                hashcpy(rm->peer_ref->old_sha1,
 762                                        peer_item->util);
 763                }
 764        }
 765
 766        if (tags == TAGS_DEFAULT && autotags)
 767                transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 768        if (fetch_refs(transport, ref_map)) {
 769                free_refs(ref_map);
 770                retcode = 1;
 771                goto cleanup;
 772        }
 773        if (prune) {
 774                /* If --tags was specified, pretend the user gave us the canonical tags refspec */
 775                if (tags == TAGS_SET) {
 776                        const char *tags_str = "refs/tags/*:refs/tags/*";
 777                        struct refspec *tags_refspec, *refspec;
 778
 779                        /* Copy the refspec and add the tags to it */
 780                        refspec = xcalloc(ref_count + 1, sizeof(struct refspec));
 781                        tags_refspec = parse_fetch_refspec(1, &tags_str);
 782                        memcpy(refspec, refs, ref_count * sizeof(struct refspec));
 783                        memcpy(&refspec[ref_count], tags_refspec, sizeof(struct refspec));
 784                        ref_count++;
 785
 786                        prune_refs(refspec, ref_count, ref_map);
 787
 788                        ref_count--;
 789                        /* The rest of the strings belong to fetch_one */
 790                        free_refspec(1, tags_refspec);
 791                        free(refspec);
 792                } else if (ref_count) {
 793                        prune_refs(refs, ref_count, ref_map);
 794                } else {
 795                        prune_refs(transport->remote->fetch, transport->remote->fetch_refspec_nr, ref_map);
 796                }
 797        }
 798        free_refs(ref_map);
 799
 800        /* if neither --no-tags nor --tags was specified, do automated tag
 801         * following ... */
 802        if (tags == TAGS_DEFAULT && autotags) {
 803                struct ref **tail = &ref_map;
 804                ref_map = NULL;
 805                find_non_local_tags(transport, &ref_map, &tail);
 806                if (ref_map) {
 807                        transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, NULL);
 808                        transport_set_option(transport, TRANS_OPT_DEPTH, "0");
 809                        fetch_refs(transport, ref_map);
 810                }
 811                free_refs(ref_map);
 812        }
 813
 814 cleanup:
 815        string_list_clear(&existing_refs, 1);
 816        return retcode;
 817}
 818
 819static void set_option(const char *name, const char *value)
 820{
 821        int r = transport_set_option(transport, name, value);
 822        if (r < 0)
 823                die(_("Option \"%s\" value \"%s\" is not valid for %s"),
 824                        name, value, transport->url);
 825        if (r > 0)
 826                warning(_("Option \"%s\" is ignored for %s\n"),
 827                        name, transport->url);
 828}
 829
 830static int get_one_remote_for_fetch(struct remote *remote, void *priv)
 831{
 832        struct string_list *list = priv;
 833        if (!remote->skip_default_update)
 834                string_list_append(list, remote->name);
 835        return 0;
 836}
 837
 838struct remote_group_data {
 839        const char *name;
 840        struct string_list *list;
 841};
 842
 843static int get_remote_group(const char *key, const char *value, void *priv)
 844{
 845        struct remote_group_data *g = priv;
 846
 847        if (!prefixcmp(key, "remotes.") &&
 848                        !strcmp(key + 8, g->name)) {
 849                /* split list by white space */
 850                int space = strcspn(value, " \t\n");
 851                while (*value) {
 852                        if (space > 1) {
 853                                string_list_append(g->list,
 854                                                   xstrndup(value, space));
 855                        }
 856                        value += space + (value[space] != '\0');
 857                        space = strcspn(value, " \t\n");
 858                }
 859        }
 860
 861        return 0;
 862}
 863
 864static int add_remote_or_group(const char *name, struct string_list *list)
 865{
 866        int prev_nr = list->nr;
 867        struct remote_group_data g;
 868        g.name = name; g.list = list;
 869
 870        git_config(get_remote_group, &g);
 871        if (list->nr == prev_nr) {
 872                struct remote *remote;
 873                if (!remote_is_configured(name))
 874                        return 0;
 875                remote = remote_get(name);
 876                string_list_append(list, remote->name);
 877        }
 878        return 1;
 879}
 880
 881static void add_options_to_argv(struct argv_array *argv)
 882{
 883        if (dry_run)
 884                argv_array_push(argv, "--dry-run");
 885        if (prune)
 886                argv_array_push(argv, "--prune");
 887        if (update_head_ok)
 888                argv_array_push(argv, "--update-head-ok");
 889        if (force)
 890                argv_array_push(argv, "--force");
 891        if (keep)
 892                argv_array_push(argv, "--keep");
 893        if (recurse_submodules == RECURSE_SUBMODULES_ON)
 894                argv_array_push(argv, "--recurse-submodules");
 895        else if (recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND)
 896                argv_array_push(argv, "--recurse-submodules=on-demand");
 897        if (tags == TAGS_SET)
 898                argv_array_push(argv, "--tags");
 899        else if (tags == TAGS_UNSET)
 900                argv_array_push(argv, "--no-tags");
 901        if (verbosity >= 2)
 902                argv_array_push(argv, "-v");
 903        if (verbosity >= 1)
 904                argv_array_push(argv, "-v");
 905        else if (verbosity < 0)
 906                argv_array_push(argv, "-q");
 907
 908}
 909
 910static int fetch_multiple(struct string_list *list)
 911{
 912        int i, result = 0;
 913        struct argv_array argv = ARGV_ARRAY_INIT;
 914
 915        if (!append && !dry_run) {
 916                int errcode = truncate_fetch_head();
 917                if (errcode)
 918                        return errcode;
 919        }
 920
 921        argv_array_pushl(&argv, "fetch", "--append", NULL);
 922        add_options_to_argv(&argv);
 923
 924        for (i = 0; i < list->nr; i++) {
 925                const char *name = list->items[i].string;
 926                argv_array_push(&argv, name);
 927                if (verbosity >= 0)
 928                        printf(_("Fetching %s\n"), name);
 929                if (run_command_v_opt(argv.argv, RUN_GIT_CMD)) {
 930                        error(_("Could not fetch %s"), name);
 931                        result = 1;
 932                }
 933                argv_array_pop(&argv);
 934        }
 935
 936        argv_array_clear(&argv);
 937        return result;
 938}
 939
 940static int fetch_one(struct remote *remote, int argc, const char **argv)
 941{
 942        int i;
 943        static const char **refs = NULL;
 944        struct refspec *refspec;
 945        int ref_nr = 0;
 946        int exit_code;
 947
 948        if (!remote)
 949                die(_("No remote repository specified.  Please, specify either a URL or a\n"
 950                    "remote name from which new revisions should be fetched."));
 951
 952        transport = transport_get(remote, NULL);
 953        transport_set_verbosity(transport, verbosity, progress);
 954        if (upload_pack)
 955                set_option(TRANS_OPT_UPLOADPACK, upload_pack);
 956        if (keep)
 957                set_option(TRANS_OPT_KEEP, "yes");
 958        if (depth)
 959                set_option(TRANS_OPT_DEPTH, depth);
 960
 961        if (argc > 0) {
 962                int j = 0;
 963                refs = xcalloc(argc + 1, sizeof(const char *));
 964                for (i = 0; i < argc; i++) {
 965                        if (!strcmp(argv[i], "tag")) {
 966                                char *ref;
 967                                i++;
 968                                if (i >= argc)
 969                                        die(_("You need to specify a tag name."));
 970                                ref = xmalloc(strlen(argv[i]) * 2 + 22);
 971                                strcpy(ref, "refs/tags/");
 972                                strcat(ref, argv[i]);
 973                                strcat(ref, ":refs/tags/");
 974                                strcat(ref, argv[i]);
 975                                refs[j++] = ref;
 976                        } else
 977                                refs[j++] = argv[i];
 978                }
 979                refs[j] = NULL;
 980                ref_nr = j;
 981        }
 982
 983        sigchain_push_common(unlock_pack_on_signal);
 984        atexit(unlock_pack);
 985        refspec = parse_fetch_refspec(ref_nr, refs);
 986        exit_code = do_fetch(transport, refspec, ref_nr);
 987        free_refspec(ref_nr, refspec);
 988        transport_disconnect(transport);
 989        transport = NULL;
 990        return exit_code;
 991}
 992
 993int cmd_fetch(int argc, const char **argv, const char *prefix)
 994{
 995        int i;
 996        struct string_list list = STRING_LIST_INIT_NODUP;
 997        struct remote *remote;
 998        int result = 0;
 999        static const char *argv_gc_auto[] = {
1000                "gc", "--auto", NULL,
1001        };
1002
1003        packet_trace_identity("fetch");
1004
1005        /* Record the command line for the reflog */
1006        strbuf_addstr(&default_rla, "fetch");
1007        for (i = 1; i < argc; i++)
1008                strbuf_addf(&default_rla, " %s", argv[i]);
1009
1010        argc = parse_options(argc, argv, prefix,
1011                             builtin_fetch_options, builtin_fetch_usage, 0);
1012
1013        if (unshallow) {
1014                if (depth)
1015                        die(_("--depth and --unshallow cannot be used together"));
1016                else if (!is_repository_shallow())
1017                        die(_("--unshallow on a complete repository does not make sense"));
1018                else {
1019                        static char inf_depth[12];
1020                        sprintf(inf_depth, "%d", INFINITE_DEPTH);
1021                        depth = inf_depth;
1022                }
1023        }
1024
1025        if (recurse_submodules != RECURSE_SUBMODULES_OFF) {
1026                if (recurse_submodules_default) {
1027                        int arg = parse_fetch_recurse_submodules_arg("--recurse-submodules-default", recurse_submodules_default);
1028                        set_config_fetch_recurse_submodules(arg);
1029                }
1030                gitmodules_config();
1031                git_config(submodule_config, NULL);
1032        }
1033
1034        if (all) {
1035                if (argc == 1)
1036                        die(_("fetch --all does not take a repository argument"));
1037                else if (argc > 1)
1038                        die(_("fetch --all does not make sense with refspecs"));
1039                (void) for_each_remote(get_one_remote_for_fetch, &list);
1040                result = fetch_multiple(&list);
1041        } else if (argc == 0) {
1042                /* No arguments -- use default remote */
1043                remote = remote_get(NULL);
1044                result = fetch_one(remote, argc, argv);
1045        } else if (multiple) {
1046                /* All arguments are assumed to be remotes or groups */
1047                for (i = 0; i < argc; i++)
1048                        if (!add_remote_or_group(argv[i], &list))
1049                                die(_("No such remote or remote group: %s"), argv[i]);
1050                result = fetch_multiple(&list);
1051        } else {
1052                /* Single remote or group */
1053                (void) add_remote_or_group(argv[0], &list);
1054                if (list.nr > 1) {
1055                        /* More than one remote */
1056                        if (argc > 1)
1057                                die(_("Fetching a group and specifying refspecs does not make sense"));
1058                        result = fetch_multiple(&list);
1059                } else {
1060                        /* Zero or one remotes */
1061                        remote = remote_get(argv[0]);
1062                        result = fetch_one(remote, argc-1, argv+1);
1063                }
1064        }
1065
1066        if (!result && (recurse_submodules != RECURSE_SUBMODULES_OFF)) {
1067                struct argv_array options = ARGV_ARRAY_INIT;
1068
1069                add_options_to_argv(&options);
1070                result = fetch_populated_submodules(&options,
1071                                                    submodule_prefix,
1072                                                    recurse_submodules,
1073                                                    verbosity < 0);
1074                argv_array_clear(&options);
1075        }
1076
1077        /* All names were strdup()ed or strndup()ed */
1078        list.strdup_strings = 1;
1079        string_list_clear(&list, 0);
1080
1081        run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
1082
1083        return result;
1084}