builtin-fetch.con commit Tidy up git mergetool's backup file behaviour (44c36d1)
   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                }
 161        }
 162        ref_remove_duplicates(ref_map);
 163
 164        return ref_map;
 165}
 166
 167static int s_update_ref(const char *action,
 168                        struct ref *ref,
 169                        int check_old)
 170{
 171        char msg[1024];
 172        char *rla = getenv("GIT_REFLOG_ACTION");
 173        static struct ref_lock *lock;
 174
 175        if (!rla)
 176                rla = default_rla.buf;
 177        snprintf(msg, sizeof(msg), "%s: %s", rla, action);
 178        lock = lock_any_ref_for_update(ref->name,
 179                                       check_old ? ref->old_sha1 : NULL, 0);
 180        if (!lock)
 181                return 1;
 182        if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
 183                return 1;
 184        return 0;
 185}
 186
 187#define SUMMARY_WIDTH (2 * DEFAULT_ABBREV + 3)
 188#define REFCOL_WIDTH  10
 189
 190static int update_local_ref(struct ref *ref,
 191                            const char *remote,
 192                            int verbose,
 193                            char *display)
 194{
 195        struct commit *current = NULL, *updated;
 196        enum object_type type;
 197        struct branch *current_branch = branch_get(NULL);
 198        const char *pretty_ref = ref->name + (
 199                !prefixcmp(ref->name, "refs/heads/") ? 11 :
 200                !prefixcmp(ref->name, "refs/tags/") ? 10 :
 201                !prefixcmp(ref->name, "refs/remotes/") ? 13 :
 202                0);
 203
 204        *display = 0;
 205        type = sha1_object_info(ref->new_sha1, NULL);
 206        if (type < 0)
 207                die("object %s not found", sha1_to_hex(ref->new_sha1));
 208
 209        if (!*ref->name) {
 210                /* Not storing */
 211                if (verbose)
 212                        sprintf(display, "* branch %s -> FETCH_HEAD", remote);
 213                return 0;
 214        }
 215
 216        if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
 217                if (verbose)
 218                        sprintf(display, "= %-*s %-*s -> %s", SUMMARY_WIDTH,
 219                                "[up to date]", REFCOL_WIDTH, remote,
 220                                pretty_ref);
 221                return 0;
 222        }
 223
 224        if (current_branch &&
 225            !strcmp(ref->name, current_branch->name) &&
 226            !(update_head_ok || is_bare_repository()) &&
 227            !is_null_sha1(ref->old_sha1)) {
 228                /*
 229                 * If this is the head, and it's not okay to update
 230                 * the head, and the old value of the head isn't empty...
 231                 */
 232                sprintf(display, "! %-*s %-*s -> %s  (can't fetch in current branch)",
 233                        SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
 234                        pretty_ref);
 235                return 1;
 236        }
 237
 238        if (!is_null_sha1(ref->old_sha1) &&
 239            !prefixcmp(ref->name, "refs/tags/")) {
 240                sprintf(display, "- %-*s %-*s -> %s",
 241                        SUMMARY_WIDTH, "[tag update]", REFCOL_WIDTH, remote,
 242                        pretty_ref);
 243                return s_update_ref("updating tag", ref, 0);
 244        }
 245
 246        current = lookup_commit_reference_gently(ref->old_sha1, 1);
 247        updated = lookup_commit_reference_gently(ref->new_sha1, 1);
 248        if (!current || !updated) {
 249                const char *msg;
 250                const char *what;
 251                if (!strncmp(ref->name, "refs/tags/", 10)) {
 252                        msg = "storing tag";
 253                        what = "[new tag]";
 254                }
 255                else {
 256                        msg = "storing head";
 257                        what = "[new branch]";
 258                }
 259
 260                sprintf(display, "* %-*s %-*s -> %s", SUMMARY_WIDTH, what,
 261                        REFCOL_WIDTH, remote, pretty_ref);
 262                return s_update_ref(msg, ref, 0);
 263        }
 264
 265        if (in_merge_bases(current, &updated, 1)) {
 266                char quickref[83];
 267                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 268                strcat(quickref, "..");
 269                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 270                sprintf(display, "  %-*s %-*s -> %s", SUMMARY_WIDTH, quickref,
 271                        REFCOL_WIDTH, remote, pretty_ref);
 272                return s_update_ref("fast forward", ref, 1);
 273        } else if (force || ref->force) {
 274                char quickref[84];
 275                strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 276                strcat(quickref, "...");
 277                strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 278                sprintf(display, "+ %-*s %-*s -> %s  (forced update)",
 279                        SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote, pretty_ref);
 280                return s_update_ref("forced-update", ref, 1);
 281        } else {
 282                sprintf(display, "! %-*s %-*s -> %s  (non fast forward)",
 283                        SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
 284                        pretty_ref);
 285                return 1;
 286        }
 287}
 288
 289static int store_updated_refs(const char *url, struct ref *ref_map)
 290{
 291        FILE *fp;
 292        struct commit *commit;
 293        int url_len, i, note_len, shown_url = 0;
 294        char note[1024];
 295        const char *what, *kind;
 296        struct ref *rm;
 297        char *filename = git_path("FETCH_HEAD");
 298
 299        fp = fopen(filename, "a");
 300        if (!fp)
 301                return error("cannot open %s: %s\n", filename, strerror(errno));
 302        for (rm = ref_map; rm; rm = rm->next) {
 303                struct ref *ref = NULL;
 304
 305                if (rm->peer_ref) {
 306                        ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
 307                        strcpy(ref->name, rm->peer_ref->name);
 308                        hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
 309                        hashcpy(ref->new_sha1, rm->old_sha1);
 310                        ref->force = rm->peer_ref->force;
 311                }
 312
 313                commit = lookup_commit_reference_gently(rm->old_sha1, 1);
 314                if (!commit)
 315                        rm->merge = 0;
 316
 317                if (!strcmp(rm->name, "HEAD")) {
 318                        kind = "";
 319                        what = "";
 320                }
 321                else if (!prefixcmp(rm->name, "refs/heads/")) {
 322                        kind = "branch";
 323                        what = rm->name + 11;
 324                }
 325                else if (!prefixcmp(rm->name, "refs/tags/")) {
 326                        kind = "tag";
 327                        what = rm->name + 10;
 328                }
 329                else if (!prefixcmp(rm->name, "refs/remotes/")) {
 330                        kind = "remote branch";
 331                        what = rm->name + 13;
 332                }
 333                else {
 334                        kind = "";
 335                        what = rm->name;
 336                }
 337
 338                url_len = strlen(url);
 339                for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
 340                        ;
 341                url_len = i + 1;
 342                if (4 < i && !strncmp(".git", url + i - 3, 4))
 343                        url_len = i - 3;
 344
 345                note_len = 0;
 346                if (*what) {
 347                        if (*kind)
 348                                note_len += sprintf(note + note_len, "%s ",
 349                                                    kind);
 350                        note_len += sprintf(note + note_len, "'%s' of ", what);
 351                }
 352                note_len += sprintf(note + note_len, "%.*s", url_len, url);
 353                fprintf(fp, "%s\t%s\t%s\n",
 354                        sha1_to_hex(commit ? commit->object.sha1 :
 355                                    rm->old_sha1),
 356                        rm->merge ? "" : "not-for-merge",
 357                        note);
 358
 359                if (ref) {
 360                        update_local_ref(ref, what, verbose, note);
 361                        if (*note) {
 362                                if (!shown_url) {
 363                                        fprintf(stderr, "From %.*s\n",
 364                                                        url_len, url);
 365                                        shown_url = 1;
 366                                }
 367                                fprintf(stderr, " %s\n", note);
 368                        }
 369                }
 370        }
 371        fclose(fp);
 372        return 0;
 373}
 374
 375/*
 376 * We would want to bypass the object transfer altogether if
 377 * everything we are going to fetch already exists and connected
 378 * locally.
 379 *
 380 * The refs we are going to fetch are in to_fetch (nr_heads in
 381 * total).  If running
 382 *
 383 *  $ git-rev-list --objects to_fetch[0] to_fetch[1] ... --not --all
 384 *
 385 * does not error out, that means everything reachable from the
 386 * refs we are going to fetch exists and is connected to some of
 387 * our existing refs.
 388 */
 389static int quickfetch(struct ref *ref_map)
 390{
 391        struct child_process revlist;
 392        struct ref *ref;
 393        char **argv;
 394        int i, err;
 395
 396        /*
 397         * If we are deepening a shallow clone we already have these
 398         * objects reachable.  Running rev-list here will return with
 399         * a good (0) exit status and we'll bypass the fetch that we
 400         * really need to perform.  Claiming failure now will ensure
 401         * we perform the network exchange to deepen our history.
 402         */
 403        if (depth)
 404                return -1;
 405
 406        for (i = 0, ref = ref_map; ref; ref = ref->next)
 407                i++;
 408        if (!i)
 409                return 0;
 410
 411        argv = xmalloc(sizeof(*argv) * (i + 6));
 412        i = 0;
 413        argv[i++] = xstrdup("rev-list");
 414        argv[i++] = xstrdup("--quiet");
 415        argv[i++] = xstrdup("--objects");
 416        for (ref = ref_map; ref; ref = ref->next)
 417                argv[i++] = xstrdup(sha1_to_hex(ref->old_sha1));
 418        argv[i++] = xstrdup("--not");
 419        argv[i++] = xstrdup("--all");
 420        argv[i++] = NULL;
 421
 422        memset(&revlist, 0, sizeof(revlist));
 423        revlist.argv = (const char**)argv;
 424        revlist.git_cmd = 1;
 425        revlist.no_stdin = 1;
 426        revlist.no_stdout = 1;
 427        revlist.no_stderr = 1;
 428        err = run_command(&revlist);
 429
 430        for (i = 0; argv[i]; i++)
 431                free(argv[i]);
 432        free(argv);
 433        return err;
 434}
 435
 436static int fetch_refs(struct transport *transport, struct ref *ref_map)
 437{
 438        int ret = quickfetch(ref_map);
 439        if (ret)
 440                ret = transport_fetch_refs(transport, ref_map);
 441        if (!ret)
 442                ret |= store_updated_refs(transport->url, ref_map);
 443        transport_unlock_pack(transport);
 444        return ret;
 445}
 446
 447static int add_existing(const char *refname, const unsigned char *sha1,
 448                        int flag, void *cbdata)
 449{
 450        struct path_list *list = (struct path_list *)cbdata;
 451        path_list_insert(refname, list);
 452        return 0;
 453}
 454
 455static struct ref *find_non_local_tags(struct transport *transport,
 456                                       struct ref *fetch_map)
 457{
 458        static struct path_list existing_refs = { NULL, 0, 0, 0 };
 459        struct path_list new_refs = { NULL, 0, 0, 1 };
 460        char *ref_name;
 461        int ref_name_len;
 462        const unsigned char *ref_sha1;
 463        const struct ref *tag_ref;
 464        struct ref *rm = NULL;
 465        struct ref *ref_map = NULL;
 466        struct ref **tail = &ref_map;
 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        return ref_map;
 508}
 509
 510static int do_fetch(struct transport *transport,
 511                    struct refspec *refs, int ref_count)
 512{
 513        struct ref *ref_map, *fetch_map;
 514        struct ref *rm;
 515        int autotags = (transport->remote->fetch_tags == 1);
 516        if (transport->remote->fetch_tags == 2 && tags != TAGS_UNSET)
 517                tags = TAGS_SET;
 518        if (transport->remote->fetch_tags == -1)
 519                tags = TAGS_UNSET;
 520
 521        if (!transport->get_refs_list || !transport->fetch)
 522                die("Don't know how to fetch from %s", transport->url);
 523
 524        /* if not appending, truncate FETCH_HEAD */
 525        if (!append) {
 526                char *filename = git_path("FETCH_HEAD");
 527                FILE *fp = fopen(filename, "w");
 528                if (!fp)
 529                        return error("cannot open %s: %s\n", filename, strerror(errno));
 530                fclose(fp);
 531        }
 532
 533        ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
 534
 535        for (rm = ref_map; rm; rm = rm->next) {
 536                if (rm->peer_ref)
 537                        read_ref(rm->peer_ref->name, rm->peer_ref->old_sha1);
 538        }
 539
 540        if (fetch_refs(transport, ref_map)) {
 541                free_refs(ref_map);
 542                return 1;
 543        }
 544
 545        fetch_map = ref_map;
 546
 547        /* if neither --no-tags nor --tags was specified, do automated tag
 548         * following ... */
 549        if (tags == TAGS_DEFAULT && autotags) {
 550                ref_map = find_non_local_tags(transport, fetch_map);
 551                if (ref_map) {
 552                        transport_set_option(transport, TRANS_OPT_DEPTH, "0");
 553                        fetch_refs(transport, ref_map);
 554                }
 555                free_refs(ref_map);
 556        }
 557
 558        free_refs(fetch_map);
 559
 560        transport_disconnect(transport);
 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, parse_ref_spec(ref_nr, refs), ref_nr);
 634}