Andrew's git / gitweb.git / builtin-fetch.c
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builtin-fetch.con commit git-fetch: avoid local fetching from alternate (again) (4191c35)
   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
  13static const char fetch_usage[] = "git-fetch [-a | --append] [--upload-pack <upload-pack>] [-f | --force] [--no-tags] [-t | --tags] [-k | --keep] [-u | --update-head-ok] [--depth <depth>] [-v | --verbose] [<repository> <refspec>...]";
  14
  15static int append, force, tags, no_tags, update_head_ok, verbose, quiet;
  16static const char *depth;
  17static char *default_rla = NULL;
  18static struct transport *transport;
  19
  20static void unlock_pack(void)
  21{
  22        if (transport)
  23                transport_unlock_pack(transport);
  24}
  25
  26static void unlock_pack_on_signal(int signo)
  27{
  28        unlock_pack();
  29        signal(SIGINT, SIG_DFL);
  30        raise(signo);
  31}
  32
  33static void add_merge_config(struct ref **head,
  34                           struct ref *remote_refs,
  35                           struct branch *branch,
  36                           struct ref ***tail)
  37{
  38        int i;
  39
  40        for (i = 0; i < branch->merge_nr; i++) {
  41                struct ref *rm, **old_tail = *tail;
  42                struct refspec refspec;
  43
  44                for (rm = *head; rm; rm = rm->next) {
  45                        if (branch_merge_matches(branch, i, rm->name)) {
  46                                rm->merge = 1;
  47                                break;
  48                        }
  49                }
  50                if (rm)
  51                        continue;
  52
  53                /*
  54                 * Not fetched to a tracking branch?  We need to fetch
  55                 * it anyway to allow this branch's "branch.$name.merge"
  56                 * to be honored by git-pull, but we do not have to
  57                 * fail if branch.$name.merge is misconfigured to point
  58                 * at a nonexisting branch.  If we were indeed called by
  59                 * git-pull, it will notice the misconfiguration because
  60                 * there is no entry in the resulting FETCH_HEAD marked
  61                 * for merging.
  62                 */
  63                refspec.src = branch->merge[i]->src;
  64                refspec.dst = NULL;
  65                refspec.pattern = 0;
  66                refspec.force = 0;
  67                get_fetch_map(remote_refs, &refspec, tail, 1);
  68                for (rm = *old_tail; rm; rm = rm->next)
  69                        rm->merge = 1;
  70        }
  71}
  72
  73static struct ref *get_ref_map(struct transport *transport,
  74                               struct refspec *refs, int ref_count, int tags,
  75                               int *autotags)
  76{
  77        int i;
  78        struct ref *rm;
  79        struct ref *ref_map = NULL;
  80        struct ref **tail = &ref_map;
  81
  82        struct ref *remote_refs = transport_get_remote_refs(transport);
  83
  84        if (ref_count || tags) {
  85                for (i = 0; i < ref_count; i++) {
  86                        get_fetch_map(remote_refs, &refs[i], &tail, 0);
  87                        if (refs[i].dst && refs[i].dst[0])
  88                                *autotags = 1;
  89                }
  90                /* Merge everything on the command line, but not --tags */
  91                for (rm = ref_map; rm; rm = rm->next)
  92                        rm->merge = 1;
  93                if (tags) {
  94                        struct refspec refspec;
  95                        refspec.src = "refs/tags/";
  96                        refspec.dst = "refs/tags/";
  97                        refspec.pattern = 1;
  98                        refspec.force = 0;
  99                        get_fetch_map(remote_refs, &refspec, &tail, 0);
 100                }
 101        } else {
 102                /* Use the defaults */
 103                struct remote *remote = transport->remote;
 104                struct branch *branch = branch_get(NULL);
 105                int has_merge = branch_has_merge_config(branch);
 106                if (remote && (remote->fetch_refspec_nr || has_merge)) {
 107                        for (i = 0; i < remote->fetch_refspec_nr; i++) {
 108                                get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
 109                                if (remote->fetch[i].dst &&
 110                                    remote->fetch[i].dst[0])
 111                                        *autotags = 1;
 112                                if (!i && !has_merge && ref_map &&
 113                                    !remote->fetch[0].pattern)
 114                                        ref_map->merge = 1;
 115                        }
 116                        /*
 117                         * if the remote we're fetching from is the same
 118                         * as given in branch.<name>.remote, we add the
 119                         * ref given in branch.<name>.merge, too.
 120                         */
 121                        if (has_merge &&
 122                            !strcmp(branch->remote_name, remote->name))
 123                                add_merge_config(&ref_map, remote_refs, branch, &tail);
 124                } else {
 125                        ref_map = get_remote_ref(remote_refs, "HEAD");
 126                        if (!ref_map)
 127                                die("Couldn't find remote ref HEAD");
 128                        ref_map->merge = 1;
 129                }
 130        }
 131        ref_remove_duplicates(ref_map);
 132
 133        return ref_map;
 134}
 135
 136static int s_update_ref(const char *action,
 137                        struct ref *ref,
 138                        int check_old)
 139{
 140        char msg[1024];
 141        char *rla = getenv("GIT_REFLOG_ACTION");
 142        static struct ref_lock *lock;
 143
 144        if (!rla)
 145                rla = default_rla;
 146        snprintf(msg, sizeof(msg), "%s: %s", rla, action);
 147        lock = lock_any_ref_for_update(ref->name,
 148                                       check_old ? ref->old_sha1 : NULL, 0);
 149        if (!lock)
 150                return 1;
 151        if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
 152                return 1;
 153        return 0;
 154}
 155
 156#define SUMMARY_WIDTH (2 * DEFAULT_ABBREV + 3)
 157
 158static int update_local_ref(struct ref *ref,
 159                            const char *remote,
 160                            int verbose,
 161                            char *display)
 162{
 163        struct commit *current = NULL, *updated;
 164        enum object_type type;
 165        struct branch *current_branch = branch_get(NULL);
 166        const char *pretty_ref = ref->name + (
 167                !prefixcmp(ref->name, "refs/heads/") ? 11 :
 168                !prefixcmp(ref->name, "refs/tags/") ? 10 :
 169                !prefixcmp(ref->name, "refs/remotes/") ? 13 :
 170                0);
 171
 172        *display = 0;
 173        type = sha1_object_info(ref->new_sha1, NULL);
 174        if (type < 0)
 175                die("object %s not found", sha1_to_hex(ref->new_sha1));
 176
 177        if (!*ref->name) {
 178                /* Not storing */
 179                if (verbose)
 180                        sprintf(display, "* branch %s -> FETCH_HEAD", remote);
 181                return 0;
 182        }
 183
 184        if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
 185                if (verbose)
 186                        sprintf(display, "= %-*s %s -> %s", SUMMARY_WIDTH,
 187                                "[up to date]", remote, pretty_ref);
 188                return 0;
 189        }
 190
 191        if (current_branch &&
 192            !strcmp(ref->name, current_branch->name) &&
 193            !(update_head_ok || is_bare_repository()) &&
 194            !is_null_sha1(ref->old_sha1)) {
 195                /*
 196                 * If this is the head, and it's not okay to update
 197                 * the head, and the old value of the head isn't empty...
 198                 */
 199                sprintf(display, "! %-*s %s -> %s  (can't  fetch in current branch)",
 200                        SUMMARY_WIDTH, "[rejected]", remote, pretty_ref);
 201                return 1;
 202        }
 203
 204        if (!is_null_sha1(ref->old_sha1) &&
 205            !prefixcmp(ref->name, "refs/tags/")) {
 206                sprintf(display, "- %-*s %s -> %s",
 207                        SUMMARY_WIDTH, "[tag update]", remote, pretty_ref);
 208                return s_update_ref("updating tag", ref, 0);
 209        }
 210
 211        current = lookup_commit_reference_gently(ref->old_sha1, 1);
 212        updated = lookup_commit_reference_gently(ref->new_sha1, 1);
 213        if (!current || !updated) {
 214                const char *msg;
 215                const char *what;
 216                if (!strncmp(ref->name, "refs/tags/", 10)) {
 217                        msg = "storing tag";
 218                        what = "[new tag]";
 219                }
 220                else {
 221                        msg = "storing head";
 222                        what = "[new branch]";
 223                }
 224
 225                sprintf(display, "* %-*s %s -> %s",
 226                        SUMMARY_WIDTH, what, remote, pretty_ref);
 227                return s_update_ref(msg, ref, 0);
 228        }
 229
 230        if (in_merge_bases(current, &updated, 1)) {
 231                char quickref[83];
 232                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 233                strcat(quickref, "..");
 234                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 235                sprintf(display, "  %-*s %s -> %s  (fast forward)",
 236                        SUMMARY_WIDTH, quickref, remote, pretty_ref);
 237                return s_update_ref("fast forward", ref, 1);
 238        } else if (force || ref->force) {
 239                char quickref[84];
 240                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 241                strcat(quickref, "...");
 242                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 243                sprintf(display, "+ %-*s %s -> %s  (forced update)",
 244                        SUMMARY_WIDTH, quickref, remote, pretty_ref);
 245                return s_update_ref("forced-update", ref, 1);
 246        } else {
 247                sprintf(display, "! %-*s %s -> %s  (non fast forward)",
 248                        SUMMARY_WIDTH, "[rejected]", remote, pretty_ref);
 249                return 1;
 250        }
 251}
 252
 253static void store_updated_refs(const char *url, struct ref *ref_map)
 254{
 255        FILE *fp;
 256        struct commit *commit;
 257        int url_len, i, note_len, shown_url = 0;
 258        char note[1024];
 259        const char *what, *kind;
 260        struct ref *rm;
 261
 262        fp = fopen(git_path("FETCH_HEAD"), "a");
 263        for (rm = ref_map; rm; rm = rm->next) {
 264                struct ref *ref = NULL;
 265
 266                if (rm->peer_ref) {
 267                        ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
 268                        strcpy(ref->name, rm->peer_ref->name);
 269                        hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
 270                        hashcpy(ref->new_sha1, rm->old_sha1);
 271                        ref->force = rm->peer_ref->force;
 272                }
 273
 274                commit = lookup_commit_reference_gently(rm->old_sha1, 1);
 275                if (!commit)
 276                        rm->merge = 0;
 277
 278                if (!strcmp(rm->name, "HEAD")) {
 279                        kind = "";
 280                        what = "";
 281                }
 282                else if (!prefixcmp(rm->name, "refs/heads/")) {
 283                        kind = "branch";
 284                        what = rm->name + 11;
 285                }
 286                else if (!prefixcmp(rm->name, "refs/tags/")) {
 287                        kind = "tag";
 288                        what = rm->name + 10;
 289                }
 290                else if (!prefixcmp(rm->name, "refs/remotes/")) {
 291                        kind = "remote branch";
 292                        what = rm->name + 13;
 293                }
 294                else {
 295                        kind = "";
 296                        what = rm->name;
 297                }
 298
 299                url_len = strlen(url);
 300                for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
 301                        ;
 302                url_len = i + 1;
 303                if (4 < i && !strncmp(".git", url + i - 3, 4))
 304                        url_len = i - 3;
 305
 306                note_len = 0;
 307                if (*what) {
 308                        if (*kind)
 309                                note_len += sprintf(note + note_len, "%s ",
 310                                                    kind);
 311                        note_len += sprintf(note + note_len, "'%s' of ", what);
 312                }
 313                note_len += sprintf(note + note_len, "%.*s", url_len, url);
 314                fprintf(fp, "%s\t%s\t%s\n",
 315                        sha1_to_hex(commit ? commit->object.sha1 :
 316                                    rm->old_sha1),
 317                        rm->merge ? "" : "not-for-merge",
 318                        note);
 319
 320                if (ref) {
 321                        update_local_ref(ref, what, verbose, note);
 322                        if (*note) {
 323                                if (!shown_url) {
 324                                        fprintf(stderr, "From %.*s\n",
 325                                                        url_len, url);
 326                                        shown_url = 1;
 327                                }
 328                                fprintf(stderr, " %s\n", note);
 329                        }
 330                }
 331        }
 332        fclose(fp);
 333}
 334
 335/*
 336 * We would want to bypass the object transfer altogether if
 337 * everything we are going to fetch already exists and connected
 338 * locally.
 339 *
 340 * The refs we are going to fetch are in to_fetch (nr_heads in
 341 * total).  If running
 342 *
 343 *  $ git-rev-list --objects to_fetch[0] to_fetch[1] ... --not --all
 344 *
 345 * does not error out, that means everything reachable from the
 346 * refs we are going to fetch exists and is connected to some of
 347 * our existing refs.
 348 */
 349static int quickfetch(struct ref *ref_map)
 350{
 351        struct child_process revlist;
 352        struct ref *ref;
 353        char **argv;
 354        int i, err;
 355
 356        /*
 357         * If we are deepening a shallow clone we already have these
 358         * objects reachable.  Running rev-list here will return with
 359         * a good (0) exit status and we'll bypass the fetch that we
 360         * really need to perform.  Claiming failure now will ensure
 361         * we perform the network exchange to deepen our history.
 362         */
 363        if (depth)
 364                return -1;
 365
 366        for (i = 0, ref = ref_map; ref; ref = ref->next)
 367                i++;
 368        if (!i)
 369                return 0;
 370
 371        argv = xmalloc(sizeof(*argv) * (i + 6));
 372        i = 0;
 373        argv[i++] = xstrdup("rev-list");
 374        argv[i++] = xstrdup("--quiet");
 375        argv[i++] = xstrdup("--objects");
 376        for (ref = ref_map; ref; ref = ref->next)
 377                argv[i++] = xstrdup(sha1_to_hex(ref->old_sha1));
 378        argv[i++] = xstrdup("--not");
 379        argv[i++] = xstrdup("--all");
 380        argv[i++] = NULL;
 381
 382        memset(&revlist, 0, sizeof(revlist));
 383        revlist.argv = (const char**)argv;
 384        revlist.git_cmd = 1;
 385        revlist.no_stdin = 1;
 386        revlist.no_stdout = 1;
 387        revlist.no_stderr = 1;
 388        err = run_command(&revlist);
 389
 390        for (i = 0; argv[i]; i++)
 391                free(argv[i]);
 392        free(argv);
 393        return err;
 394}
 395
 396static int fetch_refs(struct transport *transport, struct ref *ref_map)
 397{
 398        int ret = quickfetch(ref_map);
 399        if (ret)
 400                ret = transport_fetch_refs(transport, ref_map);
 401        if (!ret)
 402                store_updated_refs(transport->url, ref_map);
 403        transport_unlock_pack(transport);
 404        return ret;
 405}
 406
 407static int add_existing(const char *refname, const unsigned char *sha1,
 408                        int flag, void *cbdata)
 409{
 410        struct path_list *list = (struct path_list *)cbdata;
 411        path_list_insert(refname, list);
 412        return 0;
 413}
 414
 415static struct ref *find_non_local_tags(struct transport *transport,
 416                                       struct ref *fetch_map)
 417{
 418        static struct path_list existing_refs = { NULL, 0, 0, 0 };
 419        struct path_list new_refs = { NULL, 0, 0, 1 };
 420        char *ref_name;
 421        int ref_name_len;
 422        unsigned char *ref_sha1;
 423        struct ref *tag_ref;
 424        struct ref *rm = NULL;
 425        struct ref *ref_map = NULL;
 426        struct ref **tail = &ref_map;
 427        struct ref *ref;
 428
 429        for_each_ref(add_existing, &existing_refs);
 430        for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
 431                if (prefixcmp(ref->name, "refs/tags"))
 432                        continue;
 433
 434                ref_name = xstrdup(ref->name);
 435                ref_name_len = strlen(ref_name);
 436                ref_sha1 = ref->old_sha1;
 437
 438                if (!strcmp(ref_name + ref_name_len - 3, "^{}")) {
 439                        ref_name[ref_name_len - 3] = 0;
 440                        tag_ref = transport_get_remote_refs(transport);
 441                        while (tag_ref) {
 442                                if (!strcmp(tag_ref->name, ref_name)) {
 443                                        ref_sha1 = tag_ref->old_sha1;
 444                                        break;
 445                                }
 446                                tag_ref = tag_ref->next;
 447                        }
 448                }
 449
 450                if (!path_list_has_path(&existing_refs, ref_name) &&
 451                    !path_list_has_path(&new_refs, ref_name) &&
 452                    has_sha1_file(ref->old_sha1)) {
 453                        path_list_insert(ref_name, &new_refs);
 454
 455                        rm = alloc_ref(strlen(ref_name) + 1);
 456                        strcpy(rm->name, ref_name);
 457                        rm->peer_ref = alloc_ref(strlen(ref_name) + 1);
 458                        strcpy(rm->peer_ref->name, ref_name);
 459                        hashcpy(rm->old_sha1, ref_sha1);
 460
 461                        *tail = rm;
 462                        tail = &rm->next;
 463                }
 464                free(ref_name);
 465        }
 466
 467        return ref_map;
 468}
 469
 470static int do_fetch(struct transport *transport,
 471                    struct refspec *refs, int ref_count)
 472{
 473        struct ref *ref_map, *fetch_map;
 474        struct ref *rm;
 475        int autotags = (transport->remote->fetch_tags == 1);
 476        if (transport->remote->fetch_tags == 2 && !no_tags)
 477                tags = 1;
 478        if (transport->remote->fetch_tags == -1)
 479                no_tags = 1;
 480
 481        if (!transport->get_refs_list || !transport->fetch)
 482                die("Don't know how to fetch from %s", transport->url);
 483
 484        /* if not appending, truncate FETCH_HEAD */
 485        if (!append)
 486                fclose(fopen(git_path("FETCH_HEAD"), "w"));
 487
 488        ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
 489
 490        for (rm = ref_map; rm; rm = rm->next) {
 491                if (rm->peer_ref)
 492                        read_ref(rm->peer_ref->name, rm->peer_ref->old_sha1);
 493        }
 494
 495        if (fetch_refs(transport, ref_map)) {
 496                free_refs(ref_map);
 497                return 1;
 498        }
 499
 500        fetch_map = ref_map;
 501
 502        /* if neither --no-tags nor --tags was specified, do automated tag
 503         * following ... */
 504        if (!(tags || no_tags) && autotags) {
 505                ref_map = find_non_local_tags(transport, fetch_map);
 506                if (ref_map) {
 507                        transport_set_option(transport, TRANS_OPT_DEPTH, "0");
 508                        fetch_refs(transport, ref_map);
 509                }
 510                free_refs(ref_map);
 511        }
 512
 513        free_refs(fetch_map);
 514
 515        return 0;
 516}
 517
 518static void set_option(const char *name, const char *value)
 519{
 520        int r = transport_set_option(transport, name, value);
 521        if (r < 0)
 522                die("Option \"%s\" value \"%s\" is not valid for %s\n",
 523                        name, value, transport->url);
 524        if (r > 0)
 525                warning("Option \"%s\" is ignored for %s\n",
 526                        name, transport->url);
 527}
 528
 529int cmd_fetch(int argc, const char **argv, const char *prefix)
 530{
 531        struct remote *remote;
 532        int i, j, rla_offset;
 533        static const char **refs = NULL;
 534        int ref_nr = 0;
 535        int cmd_len = 0;
 536        const char *upload_pack = NULL;
 537        int keep = 0;
 538
 539        for (i = 1; i < argc; i++) {
 540                const char *arg = argv[i];
 541                cmd_len += strlen(arg);
 542
 543                if (arg[0] != '-')
 544                        break;
 545                if (!strcmp(arg, "--append") || !strcmp(arg, "-a")) {
 546                        append = 1;
 547                        continue;
 548                }
 549                if (!prefixcmp(arg, "--upload-pack=")) {
 550                        upload_pack = arg + 14;
 551                        continue;
 552                }
 553                if (!strcmp(arg, "--upload-pack")) {
 554                        i++;
 555                        if (i == argc)
 556                                usage(fetch_usage);
 557                        upload_pack = argv[i];
 558                        continue;
 559                }
 560                if (!strcmp(arg, "--force") || !strcmp(arg, "-f")) {
 561                        force = 1;
 562                        continue;
 563                }
 564                if (!strcmp(arg, "--no-tags")) {
 565                        no_tags = 1;
 566                        continue;
 567                }
 568                if (!strcmp(arg, "--tags") || !strcmp(arg, "-t")) {
 569                        tags = 1;
 570                        continue;
 571                }
 572                if (!strcmp(arg, "--keep") || !strcmp(arg, "-k")) {
 573                        keep = 1;
 574                        continue;
 575                }
 576                if (!strcmp(arg, "--update-head-ok") || !strcmp(arg, "-u")) {
 577                        update_head_ok = 1;
 578                        continue;
 579                }
 580                if (!prefixcmp(arg, "--depth=")) {
 581                        depth = arg + 8;
 582                        continue;
 583                }
 584                if (!strcmp(arg, "--depth")) {
 585                        i++;
 586                        if (i == argc)
 587                                usage(fetch_usage);
 588                        depth = argv[i];
 589                        continue;
 590                }
 591                if (!strcmp(arg, "--quiet") || !strcmp(arg, "-q")) {
 592                        quiet = 1;
 593                        continue;
 594                }
 595                if (!strcmp(arg, "--verbose") || !strcmp(arg, "-v")) {
 596                        verbose++;
 597                        continue;
 598                }
 599                usage(fetch_usage);
 600        }
 601
 602        for (j = i; j < argc; j++)
 603                cmd_len += strlen(argv[j]);
 604
 605        default_rla = xmalloc(cmd_len + 5 + argc + 1);
 606        sprintf(default_rla, "fetch");
 607        rla_offset = strlen(default_rla);
 608        for (j = 1; j < argc; j++) {
 609                sprintf(default_rla + rla_offset, " %s", argv[j]);
 610                rla_offset += strlen(argv[j]) + 1;
 611        }
 612
 613        if (i == argc)
 614                remote = remote_get(NULL);
 615        else
 616                remote = remote_get(argv[i++]);
 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 (i < argc) {
 634                int j = 0;
 635                refs = xcalloc(argc - i + 1, sizeof(const char *));
 636                while (i < argc) {
 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                        i++;
 649                }
 650                refs[j] = NULL;
 651                ref_nr = j;
 652        }
 653
 654        signal(SIGINT, unlock_pack_on_signal);
 655        atexit(unlock_pack);
 656        return do_fetch(transport, parse_ref_spec(ref_nr, refs), ref_nr);
 657}