1d3ce775ab48e5f73eaa5cb7977ce3e4c1af1881
   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_BOOLEAN('k', "keep", &keep, "keep downloaded pack"),
  44        OPT_BOOLEAN('u', "update-head-ok", &update_head_ok,
  45                    "allow updating of HEAD ref"),
  46        OPT_STRING(0, "depth", &depth, "DEPTH",
  47                   "deepen history of shallow clone"),
  48        OPT_END()
  49};
  50
  51static void unlock_pack(void)
  52{
  53        if (transport)
  54                transport_unlock_pack(transport);
  55}
  56
  57static void unlock_pack_on_signal(int signo)
  58{
  59        unlock_pack();
  60        signal(SIGINT, SIG_DFL);
  61        raise(signo);
  62}
  63
  64static void add_merge_config(struct ref **head,
  65                           const struct ref *remote_refs,
  66                           struct branch *branch,
  67                           struct ref ***tail)
  68{
  69        int i;
  70
  71        for (i = 0; i < branch->merge_nr; i++) {
  72                struct ref *rm, **old_tail = *tail;
  73                struct refspec refspec;
  74
  75                for (rm = *head; rm; rm = rm->next) {
  76                        if (branch_merge_matches(branch, i, rm->name)) {
  77                                rm->merge = 1;
  78                                break;
  79                        }
  80                }
  81                if (rm)
  82                        continue;
  83
  84                /*
  85                 * Not fetched to a tracking branch?  We need to fetch
  86                 * it anyway to allow this branch's "branch.$name.merge"
  87                 * to be honored by git-pull, but we do not have to
  88                 * fail if branch.$name.merge is misconfigured to point
  89                 * at a nonexisting branch.  If we were indeed called by
  90                 * git-pull, it will notice the misconfiguration because
  91                 * there is no entry in the resulting FETCH_HEAD marked
  92                 * for merging.
  93                 */
  94                refspec.src = branch->merge[i]->src;
  95                refspec.dst = NULL;
  96                refspec.pattern = 0;
  97                refspec.force = 0;
  98                get_fetch_map(remote_refs, &refspec, tail, 1);
  99                for (rm = *old_tail; rm; rm = rm->next)
 100                        rm->merge = 1;
 101        }
 102}
 103
 104static struct ref *get_ref_map(struct transport *transport,
 105                               struct refspec *refs, int ref_count, int tags,
 106                               int *autotags)
 107{
 108        int i;
 109        struct ref *rm;
 110        struct ref *ref_map = NULL;
 111        struct ref **tail = &ref_map;
 112
 113        const struct ref *remote_refs = transport_get_remote_refs(transport);
 114
 115        if (ref_count || tags == TAGS_SET) {
 116                for (i = 0; i < ref_count; i++) {
 117                        get_fetch_map(remote_refs, &refs[i], &tail, 0);
 118                        if (refs[i].dst && refs[i].dst[0])
 119                                *autotags = 1;
 120                }
 121                /* Merge everything on the command line, but not --tags */
 122                for (rm = ref_map; rm; rm = rm->next)
 123                        rm->merge = 1;
 124                if (tags == TAGS_SET) {
 125                        struct refspec refspec;
 126                        refspec.src = "refs/tags/";
 127                        refspec.dst = "refs/tags/";
 128                        refspec.pattern = 1;
 129                        refspec.force = 0;
 130                        get_fetch_map(remote_refs, &refspec, &tail, 0);
 131                }
 132        } else {
 133                /* Use the defaults */
 134                struct remote *remote = transport->remote;
 135                struct branch *branch = branch_get(NULL);
 136                int has_merge = branch_has_merge_config(branch);
 137                if (remote && (remote->fetch_refspec_nr || has_merge)) {
 138                        for (i = 0; i < remote->fetch_refspec_nr; i++) {
 139                                get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
 140                                if (remote->fetch[i].dst &&
 141                                    remote->fetch[i].dst[0])
 142                                        *autotags = 1;
 143                                if (!i && !has_merge && ref_map &&
 144                                    !remote->fetch[0].pattern)
 145                                        ref_map->merge = 1;
 146                        }
 147                        /*
 148                         * if the remote we're fetching from is the same
 149                         * as given in branch.<name>.remote, we add the
 150                         * ref given in branch.<name>.merge, too.
 151                         */
 152                        if (has_merge &&
 153                            !strcmp(branch->remote_name, remote->name))
 154                                add_merge_config(&ref_map, remote_refs, branch, &tail);
 155                } else {
 156                        ref_map = get_remote_ref(remote_refs, "HEAD");
 157                        if (!ref_map)
 158                                die("Couldn't find remote ref HEAD");
 159                        ref_map->merge = 1;
 160                        tail = &ref_map->next;
 161                }
 162        }
 163        ref_remove_duplicates(ref_map);
 164
 165        return ref_map;
 166}
 167
 168static int s_update_ref(const char *action,
 169                        struct ref *ref,
 170                        int check_old)
 171{
 172        char msg[1024];
 173        char *rla = getenv("GIT_REFLOG_ACTION");
 174        static struct ref_lock *lock;
 175
 176        if (!rla)
 177                rla = default_rla.buf;
 178        snprintf(msg, sizeof(msg), "%s: %s", rla, action);
 179        lock = lock_any_ref_for_update(ref->name,
 180                                       check_old ? ref->old_sha1 : NULL, 0);
 181        if (!lock)
 182                return 1;
 183        if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
 184                return 1;
 185        return 0;
 186}
 187
 188#define SUMMARY_WIDTH (2 * DEFAULT_ABBREV + 3)
 189#define REFCOL_WIDTH  10
 190
 191static int update_local_ref(struct ref *ref,
 192                            const char *remote,
 193                            int verbose,
 194                            char *display)
 195{
 196        struct commit *current = NULL, *updated;
 197        enum object_type type;
 198        struct branch *current_branch = branch_get(NULL);
 199        const char *pretty_ref = ref->name + (
 200                !prefixcmp(ref->name, "refs/heads/") ? 11 :
 201                !prefixcmp(ref->name, "refs/tags/") ? 10 :
 202                !prefixcmp(ref->name, "refs/remotes/") ? 13 :
 203                0);
 204
 205        *display = 0;
 206        type = sha1_object_info(ref->new_sha1, NULL);
 207        if (type < 0)
 208                die("object %s not found", sha1_to_hex(ref->new_sha1));
 209
 210        if (!*ref->name) {
 211                /* Not storing */
 212                if (verbose)
 213                        sprintf(display, "* branch %s -> FETCH_HEAD", remote);
 214                return 0;
 215        }
 216
 217        if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
 218                if (verbose)
 219                        sprintf(display, "= %-*s %-*s -> %s", SUMMARY_WIDTH,
 220                                "[up to date]", REFCOL_WIDTH, remote,
 221                                pretty_ref);
 222                return 0;
 223        }
 224
 225        if (current_branch &&
 226            !strcmp(ref->name, current_branch->name) &&
 227            !(update_head_ok || is_bare_repository()) &&
 228            !is_null_sha1(ref->old_sha1)) {
 229                /*
 230                 * If this is the head, and it's not okay to update
 231                 * the head, and the old value of the head isn't empty...
 232                 */
 233                sprintf(display, "! %-*s %-*s -> %s  (can't fetch in current branch)",
 234                        SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
 235                        pretty_ref);
 236                return 1;
 237        }
 238
 239        if (!is_null_sha1(ref->old_sha1) &&
 240            !prefixcmp(ref->name, "refs/tags/")) {
 241                sprintf(display, "- %-*s %-*s -> %s",
 242                        SUMMARY_WIDTH, "[tag update]", REFCOL_WIDTH, remote,
 243                        pretty_ref);
 244                return s_update_ref("updating tag", ref, 0);
 245        }
 246
 247        current = lookup_commit_reference_gently(ref->old_sha1, 1);
 248        updated = lookup_commit_reference_gently(ref->new_sha1, 1);
 249        if (!current || !updated) {
 250                const char *msg;
 251                const char *what;
 252                if (!strncmp(ref->name, "refs/tags/", 10)) {
 253                        msg = "storing tag";
 254                        what = "[new tag]";
 255                }
 256                else {
 257                        msg = "storing head";
 258                        what = "[new branch]";
 259                }
 260
 261                sprintf(display, "* %-*s %-*s -> %s", SUMMARY_WIDTH, what,
 262                        REFCOL_WIDTH, remote, pretty_ref);
 263                return s_update_ref(msg, ref, 0);
 264        }
 265
 266        if (in_merge_bases(current, &updated, 1)) {
 267                char quickref[83];
 268                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 269                strcat(quickref, "..");
 270                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 271                sprintf(display, "  %-*s %-*s -> %s", SUMMARY_WIDTH, quickref,
 272                        REFCOL_WIDTH, remote, pretty_ref);
 273                return s_update_ref("fast forward", ref, 1);
 274        } else if (force || ref->force) {
 275                char quickref[84];
 276                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 277                strcat(quickref, "...");
 278                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 279                sprintf(display, "+ %-*s %-*s -> %s  (forced update)",
 280                        SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote, pretty_ref);
 281                return s_update_ref("forced-update", ref, 1);
 282        } else {
 283                sprintf(display, "! %-*s %-*s -> %s  (non fast forward)",
 284                        SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
 285                        pretty_ref);
 286                return 1;
 287        }
 288}
 289
 290static int store_updated_refs(const char *url, struct ref *ref_map)
 291{
 292        FILE *fp;
 293        struct commit *commit;
 294        int url_len, i, note_len, shown_url = 0;
 295        char note[1024];
 296        const char *what, *kind;
 297        struct ref *rm;
 298        char *filename = git_path("FETCH_HEAD");
 299
 300        fp = fopen(filename, "a");
 301        if (!fp)
 302                return error("cannot open %s: %s\n", filename, strerror(errno));
 303        for (rm = ref_map; rm; rm = rm->next) {
 304                struct ref *ref = NULL;
 305
 306                if (rm->peer_ref) {
 307                        ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
 308                        strcpy(ref->name, rm->peer_ref->name);
 309                        hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
 310                        hashcpy(ref->new_sha1, rm->old_sha1);
 311                        ref->force = rm->peer_ref->force;
 312                }
 313
 314                commit = lookup_commit_reference_gently(rm->old_sha1, 1);
 315                if (!commit)
 316                        rm->merge = 0;
 317
 318                if (!strcmp(rm->name, "HEAD")) {
 319                        kind = "";
 320                        what = "";
 321                }
 322                else if (!prefixcmp(rm->name, "refs/heads/")) {
 323                        kind = "branch";
 324                        what = rm->name + 11;
 325                }
 326                else if (!prefixcmp(rm->name, "refs/tags/")) {
 327                        kind = "tag";
 328                        what = rm->name + 10;
 329                }
 330                else if (!prefixcmp(rm->name, "refs/remotes/")) {
 331                        kind = "remote branch";
 332                        what = rm->name + 13;
 333                }
 334                else {
 335                        kind = "";
 336                        what = rm->name;
 337                }
 338
 339                url_len = strlen(url);
 340                for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
 341                        ;
 342                url_len = i + 1;
 343                if (4 < i && !strncmp(".git", url + i - 3, 4))
 344                        url_len = i - 3;
 345
 346                note_len = 0;
 347                if (*what) {
 348                        if (*kind)
 349                                note_len += sprintf(note + note_len, "%s ",
 350                                                    kind);
 351                        note_len += sprintf(note + note_len, "'%s' of ", what);
 352                }
 353                note_len += sprintf(note + note_len, "%.*s", url_len, url);
 354                fprintf(fp, "%s\t%s\t%s\n",
 355                        sha1_to_hex(commit ? commit->object.sha1 :
 356                                    rm->old_sha1),
 357                        rm->merge ? "" : "not-for-merge",
 358                        note);
 359
 360                if (ref) {
 361                        update_local_ref(ref, what, verbose, note);
 362                        if (*note) {
 363                                if (!shown_url) {
 364                                        fprintf(stderr, "From %.*s\n",
 365                                                        url_len, url);
 366                                        shown_url = 1;
 367                                }
 368                                fprintf(stderr, " %s\n", note);
 369                        }
 370                }
 371        }
 372        fclose(fp);
 373        return 0;
 374}
 375
 376/*
 377 * We would want to bypass the object transfer altogether if
 378 * everything we are going to fetch already exists and connected
 379 * locally.
 380 *
 381 * The refs we are going to fetch are in to_fetch (nr_heads in
 382 * total).  If running
 383 *
 384 *  $ git-rev-list --objects to_fetch[0] to_fetch[1] ... --not --all
 385 *
 386 * does not error out, that means everything reachable from the
 387 * refs we are going to fetch exists and is connected to some of
 388 * our existing refs.
 389 */
 390static int quickfetch(struct ref *ref_map)
 391{
 392        struct child_process revlist;
 393        struct ref *ref;
 394        char **argv;
 395        int i, err;
 396
 397        /*
 398         * If we are deepening a shallow clone we already have these
 399         * objects reachable.  Running rev-list here will return with
 400         * a good (0) exit status and we'll bypass the fetch that we
 401         * really need to perform.  Claiming failure now will ensure
 402         * we perform the network exchange to deepen our history.
 403         */
 404        if (depth)
 405                return -1;
 406
 407        for (i = 0, ref = ref_map; ref; ref = ref->next)
 408                i++;
 409        if (!i)
 410                return 0;
 411
 412        argv = xmalloc(sizeof(*argv) * (i + 6));
 413        i = 0;
 414        argv[i++] = xstrdup("rev-list");
 415        argv[i++] = xstrdup("--quiet");
 416        argv[i++] = xstrdup("--objects");
 417        for (ref = ref_map; ref; ref = ref->next)
 418                argv[i++] = xstrdup(sha1_to_hex(ref->old_sha1));
 419        argv[i++] = xstrdup("--not");
 420        argv[i++] = xstrdup("--all");
 421        argv[i++] = NULL;
 422
 423        memset(&revlist, 0, sizeof(revlist));
 424        revlist.argv = (const char**)argv;
 425        revlist.git_cmd = 1;
 426        revlist.no_stdin = 1;
 427        revlist.no_stdout = 1;
 428        revlist.no_stderr = 1;
 429        err = run_command(&revlist);
 430
 431        for (i = 0; argv[i]; i++)
 432                free(argv[i]);
 433        free(argv);
 434        return err;
 435}
 436
 437static int fetch_refs(struct transport *transport, struct ref *ref_map)
 438{
 439        int ret = quickfetch(ref_map);
 440        if (ret)
 441                ret = transport_fetch_refs(transport, ref_map);
 442        if (!ret)
 443                ret |= store_updated_refs(transport->url, ref_map);
 444        transport_unlock_pack(transport);
 445        return ret;
 446}
 447
 448static int add_existing(const char *refname, const unsigned char *sha1,
 449                        int flag, void *cbdata)
 450{
 451        struct path_list *list = (struct path_list *)cbdata;
 452        path_list_insert(refname, list);
 453        return 0;
 454}
 455
 456static void find_non_local_tags(struct transport *transport,
 457                        struct ref **head,
 458                        struct ref ***tail)
 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        const struct ref *ref;
 468
 469        for_each_ref(add_existing, &existing_refs);
 470        for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
 471                if (prefixcmp(ref->name, "refs/tags"))
 472                        continue;
 473
 474                ref_name = xstrdup(ref->name);
 475                ref_name_len = strlen(ref_name);
 476                ref_sha1 = ref->old_sha1;
 477
 478                if (!strcmp(ref_name + ref_name_len - 3, "^{}")) {
 479                        ref_name[ref_name_len - 3] = 0;
 480                        tag_ref = transport_get_remote_refs(transport);
 481                        while (tag_ref) {
 482                                if (!strcmp(tag_ref->name, ref_name)) {
 483                                        ref_sha1 = tag_ref->old_sha1;
 484                                        break;
 485                                }
 486                                tag_ref = tag_ref->next;
 487                        }
 488                }
 489
 490                if (!path_list_has_path(&existing_refs, ref_name) &&
 491                    !path_list_has_path(&new_refs, ref_name) &&
 492                    has_sha1_file(ref->old_sha1)) {
 493                        path_list_insert(ref_name, &new_refs);
 494
 495                        rm = alloc_ref(strlen(ref_name) + 1);
 496                        strcpy(rm->name, ref_name);
 497                        rm->peer_ref = alloc_ref(strlen(ref_name) + 1);
 498                        strcpy(rm->peer_ref->name, ref_name);
 499                        hashcpy(rm->old_sha1, ref_sha1);
 500
 501                        **tail = rm;
 502                        *tail = &rm->next;
 503                }
 504                free(ref_name);
 505        }
 506}
 507
 508static int do_fetch(struct transport *transport,
 509                    struct refspec *refs, int ref_count)
 510{
 511        struct ref *ref_map;
 512        struct ref *rm;
 513        int autotags = (transport->remote->fetch_tags == 1);
 514        if (transport->remote->fetch_tags == 2 && tags != TAGS_UNSET)
 515                tags = TAGS_SET;
 516        if (transport->remote->fetch_tags == -1)
 517                tags = TAGS_UNSET;
 518
 519        if (!transport->get_refs_list || !transport->fetch)
 520                die("Don't know how to fetch from %s", transport->url);
 521
 522        /* if not appending, truncate FETCH_HEAD */
 523        if (!append) {
 524                char *filename = git_path("FETCH_HEAD");
 525                FILE *fp = fopen(filename, "w");
 526                if (!fp)
 527                        return error("cannot open %s: %s\n", filename, strerror(errno));
 528                fclose(fp);
 529        }
 530
 531        ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
 532
 533        for (rm = ref_map; rm; rm = rm->next) {
 534                if (rm->peer_ref)
 535                        read_ref(rm->peer_ref->name, rm->peer_ref->old_sha1);
 536        }
 537
 538        if (fetch_refs(transport, ref_map)) {
 539                free_refs(ref_map);
 540                return 1;
 541        }
 542        free_refs(ref_map);
 543
 544        /* if neither --no-tags nor --tags was specified, do automated tag
 545         * following ... */
 546        if (tags == TAGS_DEFAULT && autotags) {
 547                struct ref **tail = &ref_map;
 548                ref_map = NULL;
 549                find_non_local_tags(transport, &ref_map, &tail);
 550                if (ref_map) {
 551                        transport_set_option(transport, TRANS_OPT_DEPTH, "0");
 552                        fetch_refs(transport, ref_map);
 553                }
 554                free_refs(ref_map);
 555        }
 556
 557        transport_disconnect(transport);
 558
 559        return 0;
 560}
 561
 562static void set_option(const char *name, const char *value)
 563{
 564        int r = transport_set_option(transport, name, value);
 565        if (r < 0)
 566                die("Option \"%s\" value \"%s\" is not valid for %s\n",
 567                        name, value, transport->url);
 568        if (r > 0)
 569                warning("Option \"%s\" is ignored for %s\n",
 570                        name, transport->url);
 571}
 572
 573int cmd_fetch(int argc, const char **argv, const char *prefix)
 574{
 575        struct remote *remote;
 576        int i;
 577        static const char **refs = NULL;
 578        int ref_nr = 0;
 579
 580        /* Record the command line for the reflog */
 581        strbuf_addstr(&default_rla, "fetch");
 582        for (i = 1; i < argc; i++)
 583                strbuf_addf(&default_rla, " %s", argv[i]);
 584
 585        argc = parse_options(argc, argv,
 586                             builtin_fetch_options, builtin_fetch_usage, 0);
 587
 588        if (argc == 0)
 589                remote = remote_get(NULL);
 590        else
 591                remote = remote_get(argv[0]);
 592
 593        transport = transport_get(remote, remote->url[0]);
 594        if (verbose >= 2)
 595                transport->verbose = 1;
 596        if (quiet)
 597                transport->verbose = -1;
 598        if (upload_pack)
 599                set_option(TRANS_OPT_UPLOADPACK, upload_pack);
 600        if (keep)
 601                set_option(TRANS_OPT_KEEP, "yes");
 602        if (depth)
 603                set_option(TRANS_OPT_DEPTH, depth);
 604
 605        if (!transport->url)
 606                die("Where do you want to fetch from today?");
 607
 608        if (argc > 1) {
 609                int j = 0;
 610                refs = xcalloc(argc + 1, sizeof(const char *));
 611                for (i = 1; i < argc; i++) {
 612                        if (!strcmp(argv[i], "tag")) {
 613                                char *ref;
 614                                i++;
 615                                ref = xmalloc(strlen(argv[i]) * 2 + 22);
 616                                strcpy(ref, "refs/tags/");
 617                                strcat(ref, argv[i]);
 618                                strcat(ref, ":refs/tags/");
 619                                strcat(ref, argv[i]);
 620                                refs[j++] = ref;
 621                        } else
 622                                refs[j++] = argv[i];
 623                }
 624                refs[j] = NULL;
 625                ref_nr = j;
 626        }
 627
 628        signal(SIGINT, unlock_pack_on_signal);
 629        atexit(unlock_pack);
 630        return do_fetch(transport, parse_ref_spec(ref_nr, refs), ref_nr);
 631}