builtin-fetch.con commit Tighten refspec processing (c091b3d)
   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 struct ref *get_ref_map(struct transport *transport,
 107                               struct refspec *refs, int ref_count, int tags,
 108                               int *autotags)
 109{
 110        int i;
 111        struct ref *rm;
 112        struct ref *ref_map = NULL;
 113        struct ref **tail = &ref_map;
 114
 115        const struct ref *remote_refs = transport_get_remote_refs(transport);
 116
 117        if (ref_count || tags == TAGS_SET) {
 118                for (i = 0; i < ref_count; i++) {
 119                        get_fetch_map(remote_refs, &refs[i], &tail, 0);
 120                        if (refs[i].dst && refs[i].dst[0])
 121                                *autotags = 1;
 122                }
 123                /* Merge everything on the command line, but not --tags */
 124                for (rm = ref_map; rm; rm = rm->next)
 125                        rm->merge = 1;
 126                if (tags == TAGS_SET) {
 127                        struct refspec refspec;
 128                        refspec.src = "refs/tags/";
 129                        refspec.dst = "refs/tags/";
 130                        refspec.pattern = 1;
 131                        refspec.force = 0;
 132                        get_fetch_map(remote_refs, &refspec, &tail, 0);
 133                }
 134        } else {
 135                /* Use the defaults */
 136                struct remote *remote = transport->remote;
 137                struct branch *branch = branch_get(NULL);
 138                int has_merge = branch_has_merge_config(branch);
 139                if (remote && (remote->fetch_refspec_nr || has_merge)) {
 140                        for (i = 0; i < remote->fetch_refspec_nr; i++) {
 141                                get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
 142                                if (remote->fetch[i].dst &&
 143                                    remote->fetch[i].dst[0])
 144                                        *autotags = 1;
 145                                if (!i && !has_merge && ref_map &&
 146                                    !remote->fetch[0].pattern)
 147                                        ref_map->merge = 1;
 148                        }
 149                        /*
 150                         * if the remote we're fetching from is the same
 151                         * as given in branch.<name>.remote, we add the
 152                         * ref given in branch.<name>.merge, too.
 153                         */
 154                        if (has_merge &&
 155                            !strcmp(branch->remote_name, remote->name))
 156                                add_merge_config(&ref_map, remote_refs, branch, &tail);
 157                } else {
 158                        ref_map = get_remote_ref(remote_refs, "HEAD");
 159                        if (!ref_map)
 160                                die("Couldn't find remote ref HEAD");
 161                        ref_map->merge = 1;
 162                }
 163        }
 164        ref_remove_duplicates(ref_map);
 165
 166        return ref_map;
 167}
 168
 169static int s_update_ref(const char *action,
 170                        struct ref *ref,
 171                        int check_old)
 172{
 173        char msg[1024];
 174        char *rla = getenv("GIT_REFLOG_ACTION");
 175        static struct ref_lock *lock;
 176
 177        if (!rla)
 178                rla = default_rla.buf;
 179        snprintf(msg, sizeof(msg), "%s: %s", rla, action);
 180        lock = lock_any_ref_for_update(ref->name,
 181                                       check_old ? ref->old_sha1 : NULL, 0);
 182        if (!lock)
 183                return 1;
 184        if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
 185                return 1;
 186        return 0;
 187}
 188
 189#define SUMMARY_WIDTH (2 * DEFAULT_ABBREV + 3)
 190#define REFCOL_WIDTH  10
 191
 192static int update_local_ref(struct ref *ref,
 193                            const char *remote,
 194                            int verbose,
 195                            char *display)
 196{
 197        struct commit *current = NULL, *updated;
 198        enum object_type type;
 199        struct branch *current_branch = branch_get(NULL);
 200        const char *pretty_ref = ref->name + (
 201                !prefixcmp(ref->name, "refs/heads/") ? 11 :
 202                !prefixcmp(ref->name, "refs/tags/") ? 10 :
 203                !prefixcmp(ref->name, "refs/remotes/") ? 13 :
 204                0);
 205
 206        *display = 0;
 207        type = sha1_object_info(ref->new_sha1, NULL);
 208        if (type < 0)
 209                die("object %s not found", sha1_to_hex(ref->new_sha1));
 210
 211        if (!*ref->name) {
 212                /* Not storing */
 213                if (verbose)
 214                        sprintf(display, "* branch %s -> FETCH_HEAD", remote);
 215                return 0;
 216        }
 217
 218        if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
 219                if (verbose)
 220                        sprintf(display, "= %-*s %-*s -> %s", SUMMARY_WIDTH,
 221                                "[up to date]", REFCOL_WIDTH, remote,
 222                                pretty_ref);
 223                return 0;
 224        }
 225
 226        if (current_branch &&
 227            !strcmp(ref->name, current_branch->name) &&
 228            !(update_head_ok || is_bare_repository()) &&
 229            !is_null_sha1(ref->old_sha1)) {
 230                /*
 231                 * If this is the head, and it's not okay to update
 232                 * the head, and the old value of the head isn't empty...
 233                 */
 234                sprintf(display, "! %-*s %-*s -> %s  (can't fetch in current branch)",
 235                        SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
 236                        pretty_ref);
 237                return 1;
 238        }
 239
 240        if (!is_null_sha1(ref->old_sha1) &&
 241            !prefixcmp(ref->name, "refs/tags/")) {
 242                sprintf(display, "- %-*s %-*s -> %s",
 243                        SUMMARY_WIDTH, "[tag update]", REFCOL_WIDTH, remote,
 244                        pretty_ref);
 245                return s_update_ref("updating tag", ref, 0);
 246        }
 247
 248        current = lookup_commit_reference_gently(ref->old_sha1, 1);
 249        updated = lookup_commit_reference_gently(ref->new_sha1, 1);
 250        if (!current || !updated) {
 251                const char *msg;
 252                const char *what;
 253                if (!strncmp(ref->name, "refs/tags/", 10)) {
 254                        msg = "storing tag";
 255                        what = "[new tag]";
 256                }
 257                else {
 258                        msg = "storing head";
 259                        what = "[new branch]";
 260                }
 261
 262                sprintf(display, "* %-*s %-*s -> %s", SUMMARY_WIDTH, what,
 263                        REFCOL_WIDTH, remote, pretty_ref);
 264                return s_update_ref(msg, ref, 0);
 265        }
 266
 267        if (in_merge_bases(current, &updated, 1)) {
 268                char quickref[83];
 269                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 270                strcat(quickref, "..");
 271                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 272                sprintf(display, "  %-*s %-*s -> %s", SUMMARY_WIDTH, quickref,
 273                        REFCOL_WIDTH, remote, pretty_ref);
 274                return s_update_ref("fast forward", ref, 1);
 275        } else if (force || ref->force) {
 276                char quickref[84];
 277                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 278                strcat(quickref, "...");
 279                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 280                sprintf(display, "+ %-*s %-*s -> %s  (forced update)",
 281                        SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote, pretty_ref);
 282                return s_update_ref("forced-update", ref, 1);
 283        } else {
 284                sprintf(display, "! %-*s %-*s -> %s  (non fast forward)",
 285                        SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
 286                        pretty_ref);
 287                return 1;
 288        }
 289}
 290
 291static int store_updated_refs(const char *url, struct ref *ref_map)
 292{
 293        FILE *fp;
 294        struct commit *commit;
 295        int url_len, i, note_len, shown_url = 0;
 296        char note[1024];
 297        const char *what, *kind;
 298        struct ref *rm;
 299        char *filename = git_path("FETCH_HEAD");
 300
 301        fp = fopen(filename, "a");
 302        if (!fp)
 303                return error("cannot open %s: %s\n", filename, strerror(errno));
 304        for (rm = ref_map; rm; rm = rm->next) {
 305                struct ref *ref = NULL;
 306
 307                if (rm->peer_ref) {
 308                        ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
 309                        strcpy(ref->name, rm->peer_ref->name);
 310                        hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
 311                        hashcpy(ref->new_sha1, rm->old_sha1);
 312                        ref->force = rm->peer_ref->force;
 313                }
 314
 315                commit = lookup_commit_reference_gently(rm->old_sha1, 1);
 316                if (!commit)
 317                        rm->merge = 0;
 318
 319                if (!strcmp(rm->name, "HEAD")) {
 320                        kind = "";
 321                        what = "";
 322                }
 323                else if (!prefixcmp(rm->name, "refs/heads/")) {
 324                        kind = "branch";
 325                        what = rm->name + 11;
 326                }
 327                else if (!prefixcmp(rm->name, "refs/tags/")) {
 328                        kind = "tag";
 329                        what = rm->name + 10;
 330                }
 331                else if (!prefixcmp(rm->name, "refs/remotes/")) {
 332                        kind = "remote branch";
 333                        what = rm->name + 13;
 334                }
 335                else {
 336                        kind = "";
 337                        what = rm->name;
 338                }
 339
 340                url_len = strlen(url);
 341                for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
 342                        ;
 343                url_len = i + 1;
 344                if (4 < i && !strncmp(".git", url + i - 3, 4))
 345                        url_len = i - 3;
 346
 347                note_len = 0;
 348                if (*what) {
 349                        if (*kind)
 350                                note_len += sprintf(note + note_len, "%s ",
 351                                                    kind);
 352                        note_len += sprintf(note + note_len, "'%s' of ", what);
 353                }
 354                note_len += sprintf(note + note_len, "%.*s", url_len, url);
 355                fprintf(fp, "%s\t%s\t%s\n",
 356                        sha1_to_hex(commit ? commit->object.sha1 :
 357                                    rm->old_sha1),
 358                        rm->merge ? "" : "not-for-merge",
 359                        note);
 360
 361                if (ref) {
 362                        update_local_ref(ref, what, verbose, note);
 363                        if (*note) {
 364                                if (!shown_url) {
 365                                        fprintf(stderr, "From %.*s\n",
 366                                                        url_len, url);
 367                                        shown_url = 1;
 368                                }
 369                                fprintf(stderr, " %s\n", note);
 370                        }
 371                }
 372        }
 373        fclose(fp);
 374        return 0;
 375}
 376
 377/*
 378 * We would want to bypass the object transfer altogether if
 379 * everything we are going to fetch already exists and connected
 380 * locally.
 381 *
 382 * The refs we are going to fetch are in to_fetch (nr_heads in
 383 * total).  If running
 384 *
 385 *  $ git-rev-list --objects to_fetch[0] to_fetch[1] ... --not --all
 386 *
 387 * does not error out, that means everything reachable from the
 388 * refs we are going to fetch exists and is connected to some of
 389 * our existing refs.
 390 */
 391static int quickfetch(struct ref *ref_map)
 392{
 393        struct child_process revlist;
 394        struct ref *ref;
 395        char **argv;
 396        int i, err;
 397
 398        /*
 399         * If we are deepening a shallow clone we already have these
 400         * objects reachable.  Running rev-list here will return with
 401         * a good (0) exit status and we'll bypass the fetch that we
 402         * really need to perform.  Claiming failure now will ensure
 403         * we perform the network exchange to deepen our history.
 404         */
 405        if (depth)
 406                return -1;
 407
 408        for (i = 0, ref = ref_map; ref; ref = ref->next)
 409                i++;
 410        if (!i)
 411                return 0;
 412
 413        argv = xmalloc(sizeof(*argv) * (i + 6));
 414        i = 0;
 415        argv[i++] = xstrdup("rev-list");
 416        argv[i++] = xstrdup("--quiet");
 417        argv[i++] = xstrdup("--objects");
 418        for (ref = ref_map; ref; ref = ref->next)
 419                argv[i++] = xstrdup(sha1_to_hex(ref->old_sha1));
 420        argv[i++] = xstrdup("--not");
 421        argv[i++] = xstrdup("--all");
 422        argv[i++] = NULL;
 423
 424        memset(&revlist, 0, sizeof(revlist));
 425        revlist.argv = (const char**)argv;
 426        revlist.git_cmd = 1;
 427        revlist.no_stdin = 1;
 428        revlist.no_stdout = 1;
 429        revlist.no_stderr = 1;
 430        err = run_command(&revlist);
 431
 432        for (i = 0; argv[i]; i++)
 433                free(argv[i]);
 434        free(argv);
 435        return err;
 436}
 437
 438static int fetch_refs(struct transport *transport, struct ref *ref_map)
 439{
 440        int ret = quickfetch(ref_map);
 441        if (ret)
 442                ret = transport_fetch_refs(transport, ref_map);
 443        if (!ret)
 444                ret |= store_updated_refs(transport->url, ref_map);
 445        transport_unlock_pack(transport);
 446        return ret;
 447}
 448
 449static int add_existing(const char *refname, const unsigned char *sha1,
 450                        int flag, void *cbdata)
 451{
 452        struct path_list *list = (struct path_list *)cbdata;
 453        path_list_insert(refname, list);
 454        return 0;
 455}
 456
 457static struct ref *find_non_local_tags(struct transport *transport,
 458                                       struct ref *fetch_map)
 459{
 460        static struct path_list existing_refs = { NULL, 0, 0, 0 };
 461        struct path_list new_refs = { NULL, 0, 0, 1 };
 462        char *ref_name;
 463        int ref_name_len;
 464        const unsigned char *ref_sha1;
 465        const struct ref *tag_ref;
 466        struct ref *rm = NULL;
 467        struct ref *ref_map = NULL;
 468        struct ref **tail = &ref_map;
 469        const struct ref *ref;
 470
 471        for_each_ref(add_existing, &existing_refs);
 472        for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
 473                if (prefixcmp(ref->name, "refs/tags"))
 474                        continue;
 475
 476                ref_name = xstrdup(ref->name);
 477                ref_name_len = strlen(ref_name);
 478                ref_sha1 = ref->old_sha1;
 479
 480                if (!strcmp(ref_name + ref_name_len - 3, "^{}")) {
 481                        ref_name[ref_name_len - 3] = 0;
 482                        tag_ref = transport_get_remote_refs(transport);
 483                        while (tag_ref) {
 484                                if (!strcmp(tag_ref->name, ref_name)) {
 485                                        ref_sha1 = tag_ref->old_sha1;
 486                                        break;
 487                                }
 488                                tag_ref = tag_ref->next;
 489                        }
 490                }
 491
 492                if (!path_list_has_path(&existing_refs, ref_name) &&
 493                    !path_list_has_path(&new_refs, ref_name) &&
 494                    has_sha1_file(ref->old_sha1)) {
 495                        path_list_insert(ref_name, &new_refs);
 496
 497                        rm = alloc_ref(strlen(ref_name) + 1);
 498                        strcpy(rm->name, ref_name);
 499                        rm->peer_ref = alloc_ref(strlen(ref_name) + 1);
 500                        strcpy(rm->peer_ref->name, ref_name);
 501                        hashcpy(rm->old_sha1, ref_sha1);
 502
 503                        *tail = rm;
 504                        tail = &rm->next;
 505                }
 506                free(ref_name);
 507        }
 508
 509        return ref_map;
 510}
 511
 512static int do_fetch(struct transport *transport,
 513                    struct refspec *refs, int ref_count)
 514{
 515        struct ref *ref_map, *fetch_map;
 516        struct ref *rm;
 517        int autotags = (transport->remote->fetch_tags == 1);
 518        if (transport->remote->fetch_tags == 2 && tags != TAGS_UNSET)
 519                tags = TAGS_SET;
 520        if (transport->remote->fetch_tags == -1)
 521                tags = TAGS_UNSET;
 522
 523        if (!transport->get_refs_list || !transport->fetch)
 524                die("Don't know how to fetch from %s", transport->url);
 525
 526        /* if not appending, truncate FETCH_HEAD */
 527        if (!append) {
 528                char *filename = git_path("FETCH_HEAD");
 529                FILE *fp = fopen(filename, "w");
 530                if (!fp)
 531                        return error("cannot open %s: %s\n", filename, strerror(errno));
 532                fclose(fp);
 533        }
 534
 535        ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
 536
 537        for (rm = ref_map; rm; rm = rm->next) {
 538                if (rm->peer_ref)
 539                        read_ref(rm->peer_ref->name, rm->peer_ref->old_sha1);
 540        }
 541
 542        if (fetch_refs(transport, ref_map)) {
 543                free_refs(ref_map);
 544                return 1;
 545        }
 546
 547        fetch_map = ref_map;
 548
 549        /* if neither --no-tags nor --tags was specified, do automated tag
 550         * following ... */
 551        if (tags == TAGS_DEFAULT && autotags) {
 552                ref_map = find_non_local_tags(transport, fetch_map);
 553                if (ref_map) {
 554                        transport_set_option(transport, TRANS_OPT_DEPTH, "0");
 555                        fetch_refs(transport, ref_map);
 556                }
 557                free_refs(ref_map);
 558        }
 559
 560        free_refs(fetch_map);
 561
 562        return 0;
 563}
 564
 565static void set_option(const char *name, const char *value)
 566{
 567        int r = transport_set_option(transport, name, value);
 568        if (r < 0)
 569                die("Option \"%s\" value \"%s\" is not valid for %s\n",
 570                        name, value, transport->url);
 571        if (r > 0)
 572                warning("Option \"%s\" is ignored for %s\n",
 573                        name, transport->url);
 574}
 575
 576int cmd_fetch(int argc, const char **argv, const char *prefix)
 577{
 578        struct remote *remote;
 579        int i;
 580        static const char **refs = NULL;
 581        int ref_nr = 0;
 582
 583        /* Record the command line for the reflog */
 584        strbuf_addstr(&default_rla, "fetch");
 585        for (i = 1; i < argc; i++)
 586                strbuf_addf(&default_rla, " %s", argv[i]);
 587
 588        argc = parse_options(argc, argv,
 589                             builtin_fetch_options, builtin_fetch_usage, 0);
 590
 591        if (argc == 0)
 592                remote = remote_get(NULL);
 593        else
 594                remote = remote_get(argv[0]);
 595
 596        transport = transport_get(remote, remote->url[0]);
 597        if (verbose >= 2)
 598                transport->verbose = 1;
 599        if (quiet)
 600                transport->verbose = -1;
 601        if (upload_pack)
 602                set_option(TRANS_OPT_UPLOADPACK, upload_pack);
 603        if (keep)
 604                set_option(TRANS_OPT_KEEP, "yes");
 605        if (depth)
 606                set_option(TRANS_OPT_DEPTH, depth);
 607
 608        if (!transport->url)
 609                die("Where do you want to fetch from today?");
 610
 611        if (argc > 1) {
 612                int j = 0;
 613                refs = xcalloc(argc + 1, sizeof(const char *));
 614                for (i = 1; i < argc; i++) {
 615                        if (!strcmp(argv[i], "tag")) {
 616                                char *ref;
 617                                i++;
 618                                ref = xmalloc(strlen(argv[i]) * 2 + 22);
 619                                strcpy(ref, "refs/tags/");
 620                                strcat(ref, argv[i]);
 621                                strcat(ref, ":refs/tags/");
 622                                strcat(ref, argv[i]);
 623                                refs[j++] = ref;
 624                        } else
 625                                refs[j++] = argv[i];
 626                }
 627                refs[j] = NULL;
 628                ref_nr = j;
 629        }
 630
 631        signal(SIGINT, unlock_pack_on_signal);
 632        atexit(unlock_pack);
 633        return do_fetch(transport,
 634                        parse_fetch_refspec(ref_nr, refs), ref_nr);
 635}