Andrew's git / gitweb.git / remote.c
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remote.con commit GIT 1.5.6-rc2 (218bf69)
   1#include "cache.h"
   2#include "remote.h"
   3#include "refs.h"
   4
   5static struct refspec s_tag_refspec = {
   6        0,
   7        1,
   8        0,
   9        "refs/tags/",
  10        "refs/tags/"
  11};
  12
  13const struct refspec *tag_refspec = &s_tag_refspec;
  14
  15struct counted_string {
  16        size_t len;
  17        const char *s;
  18};
  19struct rewrite {
  20        const char *base;
  21        size_t baselen;
  22        struct counted_string *instead_of;
  23        int instead_of_nr;
  24        int instead_of_alloc;
  25};
  26
  27static struct remote **remotes;
  28static int remotes_alloc;
  29static int remotes_nr;
  30
  31static struct branch **branches;
  32static int branches_alloc;
  33static int branches_nr;
  34
  35static struct branch *current_branch;
  36static const char *default_remote_name;
  37
  38static struct rewrite **rewrite;
  39static int rewrite_alloc;
  40static int rewrite_nr;
  41
  42#define BUF_SIZE (2048)
  43static char buffer[BUF_SIZE];
  44
  45static const char *alias_url(const char *url)
  46{
  47        int i, j;
  48        char *ret;
  49        struct counted_string *longest;
  50        int longest_i;
  51
  52        longest = NULL;
  53        longest_i = -1;
  54        for (i = 0; i < rewrite_nr; i++) {
  55                if (!rewrite[i])
  56                        continue;
  57                for (j = 0; j < rewrite[i]->instead_of_nr; j++) {
  58                        if (!prefixcmp(url, rewrite[i]->instead_of[j].s) &&
  59                            (!longest ||
  60                             longest->len < rewrite[i]->instead_of[j].len)) {
  61                                longest = &(rewrite[i]->instead_of[j]);
  62                                longest_i = i;
  63                        }
  64                }
  65        }
  66        if (!longest)
  67                return url;
  68
  69        ret = malloc(rewrite[longest_i]->baselen +
  70                     (strlen(url) - longest->len) + 1);
  71        strcpy(ret, rewrite[longest_i]->base);
  72        strcpy(ret + rewrite[longest_i]->baselen, url + longest->len);
  73        return ret;
  74}
  75
  76static void add_push_refspec(struct remote *remote, const char *ref)
  77{
  78        ALLOC_GROW(remote->push_refspec,
  79                   remote->push_refspec_nr + 1,
  80                   remote->push_refspec_alloc);
  81        remote->push_refspec[remote->push_refspec_nr++] = ref;
  82}
  83
  84static void add_fetch_refspec(struct remote *remote, const char *ref)
  85{
  86        ALLOC_GROW(remote->fetch_refspec,
  87                   remote->fetch_refspec_nr + 1,
  88                   remote->fetch_refspec_alloc);
  89        remote->fetch_refspec[remote->fetch_refspec_nr++] = ref;
  90}
  91
  92static void add_url(struct remote *remote, const char *url)
  93{
  94        ALLOC_GROW(remote->url, remote->url_nr + 1, remote->url_alloc);
  95        remote->url[remote->url_nr++] = url;
  96}
  97
  98static void add_url_alias(struct remote *remote, const char *url)
  99{
 100        add_url(remote, alias_url(url));
 101}
 102
 103static struct remote *make_remote(const char *name, int len)
 104{
 105        struct remote *ret;
 106        int i;
 107
 108        for (i = 0; i < remotes_nr; i++) {
 109                if (len ? (!strncmp(name, remotes[i]->name, len) &&
 110                           !remotes[i]->name[len]) :
 111                    !strcmp(name, remotes[i]->name))
 112                        return remotes[i];
 113        }
 114
 115        ret = xcalloc(1, sizeof(struct remote));
 116        ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 117        remotes[remotes_nr++] = ret;
 118        if (len)
 119                ret->name = xstrndup(name, len);
 120        else
 121                ret->name = xstrdup(name);
 122        return ret;
 123}
 124
 125static void add_merge(struct branch *branch, const char *name)
 126{
 127        ALLOC_GROW(branch->merge_name, branch->merge_nr + 1,
 128                   branch->merge_alloc);
 129        branch->merge_name[branch->merge_nr++] = name;
 130}
 131
 132static struct branch *make_branch(const char *name, int len)
 133{
 134        struct branch *ret;
 135        int i;
 136        char *refname;
 137
 138        for (i = 0; i < branches_nr; i++) {
 139                if (len ? (!strncmp(name, branches[i]->name, len) &&
 140                           !branches[i]->name[len]) :
 141                    !strcmp(name, branches[i]->name))
 142                        return branches[i];
 143        }
 144
 145        ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 146        ret = xcalloc(1, sizeof(struct branch));
 147        branches[branches_nr++] = ret;
 148        if (len)
 149                ret->name = xstrndup(name, len);
 150        else
 151                ret->name = xstrdup(name);
 152        refname = malloc(strlen(name) + strlen("refs/heads/") + 1);
 153        strcpy(refname, "refs/heads/");
 154        strcpy(refname + strlen("refs/heads/"), ret->name);
 155        ret->refname = refname;
 156
 157        return ret;
 158}
 159
 160static struct rewrite *make_rewrite(const char *base, int len)
 161{
 162        struct rewrite *ret;
 163        int i;
 164
 165        for (i = 0; i < rewrite_nr; i++) {
 166                if (len
 167                    ? (len == rewrite[i]->baselen &&
 168                       !strncmp(base, rewrite[i]->base, len))
 169                    : !strcmp(base, rewrite[i]->base))
 170                        return rewrite[i];
 171        }
 172
 173        ALLOC_GROW(rewrite, rewrite_nr + 1, rewrite_alloc);
 174        ret = xcalloc(1, sizeof(struct rewrite));
 175        rewrite[rewrite_nr++] = ret;
 176        if (len) {
 177                ret->base = xstrndup(base, len);
 178                ret->baselen = len;
 179        }
 180        else {
 181                ret->base = xstrdup(base);
 182                ret->baselen = strlen(base);
 183        }
 184        return ret;
 185}
 186
 187static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 188{
 189        ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 190        rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 191        rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 192        rewrite->instead_of_nr++;
 193}
 194
 195static void read_remotes_file(struct remote *remote)
 196{
 197        FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
 198
 199        if (!f)
 200                return;
 201        while (fgets(buffer, BUF_SIZE, f)) {
 202                int value_list;
 203                char *s, *p;
 204
 205                if (!prefixcmp(buffer, "URL:")) {
 206                        value_list = 0;
 207                        s = buffer + 4;
 208                } else if (!prefixcmp(buffer, "Push:")) {
 209                        value_list = 1;
 210                        s = buffer + 5;
 211                } else if (!prefixcmp(buffer, "Pull:")) {
 212                        value_list = 2;
 213                        s = buffer + 5;
 214                } else
 215                        continue;
 216
 217                while (isspace(*s))
 218                        s++;
 219                if (!*s)
 220                        continue;
 221
 222                p = s + strlen(s);
 223                while (isspace(p[-1]))
 224                        *--p = 0;
 225
 226                switch (value_list) {
 227                case 0:
 228                        add_url_alias(remote, xstrdup(s));
 229                        break;
 230                case 1:
 231                        add_push_refspec(remote, xstrdup(s));
 232                        break;
 233                case 2:
 234                        add_fetch_refspec(remote, xstrdup(s));
 235                        break;
 236                }
 237        }
 238        fclose(f);
 239}
 240
 241static void read_branches_file(struct remote *remote)
 242{
 243        const char *slash = strchr(remote->name, '/');
 244        char *frag;
 245        struct strbuf branch;
 246        int n = slash ? slash - remote->name : 1000;
 247        FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 248        char *s, *p;
 249        int len;
 250
 251        if (!f)
 252                return;
 253        s = fgets(buffer, BUF_SIZE, f);
 254        fclose(f);
 255        if (!s)
 256                return;
 257        while (isspace(*s))
 258                s++;
 259        if (!*s)
 260                return;
 261        p = s + strlen(s);
 262        while (isspace(p[-1]))
 263                *--p = 0;
 264        len = p - s;
 265        if (slash)
 266                len += strlen(slash);
 267        p = xmalloc(len + 1);
 268        strcpy(p, s);
 269        if (slash)
 270                strcat(p, slash);
 271
 272        /*
 273         * With "slash", e.g. "git fetch jgarzik/netdev-2.6" when
 274         * reading from $GIT_DIR/branches/jgarzik fetches "HEAD" from
 275         * the partial URL obtained from the branches file plus
 276         * "/netdev-2.6" and does not store it in any tracking ref.
 277         * #branch specifier in the file is ignored.
 278         *
 279         * Otherwise, the branches file would have URL and optionally
 280         * #branch specified.  The "master" (or specified) branch is
 281         * fetched and stored in the local branch of the same name.
 282         */
 283        strbuf_init(&branch, 0);
 284        frag = strchr(p, '#');
 285        if (frag) {
 286                *(frag++) = '\0';
 287                strbuf_addf(&branch, "refs/heads/%s", frag);
 288        } else
 289                strbuf_addstr(&branch, "refs/heads/master");
 290        if (!slash) {
 291                strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 292        } else {
 293                strbuf_reset(&branch);
 294                strbuf_addstr(&branch, "HEAD:");
 295        }
 296        add_url_alias(remote, p);
 297        add_fetch_refspec(remote, strbuf_detach(&branch, 0));
 298        remote->fetch_tags = 1; /* always auto-follow */
 299}
 300
 301static int handle_config(const char *key, const char *value, void *cb)
 302{
 303        const char *name;
 304        const char *subkey;
 305        struct remote *remote;
 306        struct branch *branch;
 307        if (!prefixcmp(key, "branch.")) {
 308                name = key + 7;
 309                subkey = strrchr(name, '.');
 310                if (!subkey)
 311                        return 0;
 312                branch = make_branch(name, subkey - name);
 313                if (!strcmp(subkey, ".remote")) {
 314                        if (!value)
 315                                return config_error_nonbool(key);
 316                        branch->remote_name = xstrdup(value);
 317                        if (branch == current_branch)
 318                                default_remote_name = branch->remote_name;
 319                } else if (!strcmp(subkey, ".merge")) {
 320                        if (!value)
 321                                return config_error_nonbool(key);
 322                        add_merge(branch, xstrdup(value));
 323                }
 324                return 0;
 325        }
 326        if (!prefixcmp(key, "url.")) {
 327                struct rewrite *rewrite;
 328                name = key + 4;
 329                subkey = strrchr(name, '.');
 330                if (!subkey)
 331                        return 0;
 332                rewrite = make_rewrite(name, subkey - name);
 333                if (!strcmp(subkey, ".insteadof")) {
 334                        if (!value)
 335                                return config_error_nonbool(key);
 336                        add_instead_of(rewrite, xstrdup(value));
 337                }
 338        }
 339        if (prefixcmp(key,  "remote."))
 340                return 0;
 341        name = key + 7;
 342        subkey = strrchr(name, '.');
 343        if (!subkey)
 344                return error("Config with no key for remote %s", name);
 345        if (*subkey == '/') {
 346                warning("Config remote shorthand cannot begin with '/': %s", name);
 347                return 0;
 348        }
 349        remote = make_remote(name, subkey - name);
 350        if (!strcmp(subkey, ".mirror"))
 351                remote->mirror = git_config_bool(key, value);
 352        else if (!strcmp(subkey, ".skipdefaultupdate"))
 353                remote->skip_default_update = git_config_bool(key, value);
 354
 355        else if (!strcmp(subkey, ".url")) {
 356                const char *v;
 357                if (git_config_string(&v, key, value))
 358                        return -1;
 359                add_url(remote, v);
 360        } else if (!strcmp(subkey, ".push")) {
 361                const char *v;
 362                if (git_config_string(&v, key, value))
 363                        return -1;
 364                add_push_refspec(remote, v);
 365        } else if (!strcmp(subkey, ".fetch")) {
 366                const char *v;
 367                if (git_config_string(&v, key, value))
 368                        return -1;
 369                add_fetch_refspec(remote, v);
 370        } else if (!strcmp(subkey, ".receivepack")) {
 371                const char *v;
 372                if (git_config_string(&v, key, value))
 373                        return -1;
 374                if (!remote->receivepack)
 375                        remote->receivepack = v;
 376                else
 377                        error("more than one receivepack given, using the first");
 378        } else if (!strcmp(subkey, ".uploadpack")) {
 379                const char *v;
 380                if (git_config_string(&v, key, value))
 381                        return -1;
 382                if (!remote->uploadpack)
 383                        remote->uploadpack = v;
 384                else
 385                        error("more than one uploadpack given, using the first");
 386        } else if (!strcmp(subkey, ".tagopt")) {
 387                if (!strcmp(value, "--no-tags"))
 388                        remote->fetch_tags = -1;
 389        } else if (!strcmp(subkey, ".proxy")) {
 390                return git_config_string((const char **)&remote->http_proxy,
 391                                         key, value);
 392        }
 393        return 0;
 394}
 395
 396static void alias_all_urls(void)
 397{
 398        int i, j;
 399        for (i = 0; i < remotes_nr; i++) {
 400                if (!remotes[i])
 401                        continue;
 402                for (j = 0; j < remotes[i]->url_nr; j++) {
 403                        remotes[i]->url[j] = alias_url(remotes[i]->url[j]);
 404                }
 405        }
 406}
 407
 408static void read_config(void)
 409{
 410        unsigned char sha1[20];
 411        const char *head_ref;
 412        int flag;
 413        if (default_remote_name) // did this already
 414                return;
 415        default_remote_name = xstrdup("origin");
 416        current_branch = NULL;
 417        head_ref = resolve_ref("HEAD", sha1, 0, &flag);
 418        if (head_ref && (flag & REF_ISSYMREF) &&
 419            !prefixcmp(head_ref, "refs/heads/")) {
 420                current_branch =
 421                        make_branch(head_ref + strlen("refs/heads/"), 0);
 422        }
 423        git_config(handle_config, NULL);
 424        alias_all_urls();
 425}
 426
 427static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 428{
 429        int i;
 430        int st;
 431        struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 432
 433        for (i = 0; i < nr_refspec; i++) {
 434                size_t llen, rlen;
 435                int is_glob;
 436                const char *lhs, *rhs;
 437
 438                llen = rlen = is_glob = 0;
 439
 440                lhs = refspec[i];
 441                if (*lhs == '+') {
 442                        rs[i].force = 1;
 443                        lhs++;
 444                }
 445
 446                rhs = strrchr(lhs, ':');
 447
 448                /*
 449                 * Before going on, special case ":" (or "+:") as a refspec
 450                 * for matching refs.
 451                 */
 452                if (!fetch && rhs == lhs && rhs[1] == '\0') {
 453                        rs[i].matching = 1;
 454                        continue;
 455                }
 456
 457                if (rhs) {
 458                        rhs++;
 459                        rlen = strlen(rhs);
 460                        is_glob = (2 <= rlen && !strcmp(rhs + rlen - 2, "/*"));
 461                        if (is_glob)
 462                                rlen -= 2;
 463                        rs[i].dst = xstrndup(rhs, rlen);
 464                }
 465
 466                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 467                if (2 <= llen && !memcmp(lhs + llen - 2, "/*", 2)) {
 468                        if ((rhs && !is_glob) || (!rhs && fetch))
 469                                goto invalid;
 470                        is_glob = 1;
 471                        llen -= 2;
 472                } else if (rhs && is_glob) {
 473                        goto invalid;
 474                }
 475
 476                rs[i].pattern = is_glob;
 477                rs[i].src = xstrndup(lhs, llen);
 478
 479                if (fetch) {
 480                        /*
 481                         * LHS
 482                         * - empty is allowed; it means HEAD.
 483                         * - otherwise it must be a valid looking ref.
 484                         */
 485                        if (!*rs[i].src)
 486                                ; /* empty is ok */
 487                        else {
 488                                st = check_ref_format(rs[i].src);
 489                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 490                                        goto invalid;
 491                        }
 492                        /*
 493                         * RHS
 494                         * - missing is ok, and is same as empty.
 495                         * - empty is ok; it means not to store.
 496                         * - otherwise it must be a valid looking ref.
 497                         */
 498                        if (!rs[i].dst) {
 499                                ; /* ok */
 500                        } else if (!*rs[i].dst) {
 501                                ; /* ok */
 502                        } else {
 503                                st = check_ref_format(rs[i].dst);
 504                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 505                                        goto invalid;
 506                        }
 507                } else {
 508                        /*
 509                         * LHS
 510                         * - empty is allowed; it means delete.
 511                         * - when wildcarded, it must be a valid looking ref.
 512                         * - otherwise, it must be an extended SHA-1, but
 513                         *   there is no existing way to validate this.
 514                         */
 515                        if (!*rs[i].src)
 516                                ; /* empty is ok */
 517                        else if (is_glob) {
 518                                st = check_ref_format(rs[i].src);
 519                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 520                                        goto invalid;
 521                        }
 522                        else
 523                                ; /* anything goes, for now */
 524                        /*
 525                         * RHS
 526                         * - missing is allowed, but LHS then must be a
 527                         *   valid looking ref.
 528                         * - empty is not allowed.
 529                         * - otherwise it must be a valid looking ref.
 530                         */
 531                        if (!rs[i].dst) {
 532                                st = check_ref_format(rs[i].src);
 533                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 534                                        goto invalid;
 535                        } else if (!*rs[i].dst) {
 536                                goto invalid;
 537                        } else {
 538                                st = check_ref_format(rs[i].dst);
 539                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 540                                        goto invalid;
 541                        }
 542                }
 543        }
 544        return rs;
 545
 546 invalid:
 547        if (verify) {
 548                free(rs);
 549                return NULL;
 550        }
 551        die("Invalid refspec '%s'", refspec[i]);
 552}
 553
 554int valid_fetch_refspec(const char *fetch_refspec_str)
 555{
 556        const char *fetch_refspec[] = { fetch_refspec_str };
 557        struct refspec *refspec;
 558
 559        refspec = parse_refspec_internal(1, fetch_refspec, 1, 1);
 560        if (refspec)
 561                free(refspec);
 562        return !!refspec;
 563}
 564
 565struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 566{
 567        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 568}
 569
 570struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 571{
 572        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 573}
 574
 575static int valid_remote_nick(const char *name)
 576{
 577        if (!name[0] || /* not empty */
 578            (name[0] == '.' && /* not "." */
 579             (!name[1] || /* not ".." */
 580              (name[1] == '.' && !name[2]))))
 581                return 0;
 582        return !strchr(name, '/'); /* no slash */
 583}
 584
 585struct remote *remote_get(const char *name)
 586{
 587        struct remote *ret;
 588
 589        read_config();
 590        if (!name)
 591                name = default_remote_name;
 592        ret = make_remote(name, 0);
 593        if (valid_remote_nick(name)) {
 594                if (!ret->url)
 595                        read_remotes_file(ret);
 596                if (!ret->url)
 597                        read_branches_file(ret);
 598        }
 599        if (!ret->url)
 600                add_url_alias(ret, name);
 601        if (!ret->url)
 602                return NULL;
 603        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 604        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 605        return ret;
 606}
 607
 608int for_each_remote(each_remote_fn fn, void *priv)
 609{
 610        int i, result = 0;
 611        read_config();
 612        for (i = 0; i < remotes_nr && !result; i++) {
 613                struct remote *r = remotes[i];
 614                if (!r)
 615                        continue;
 616                if (!r->fetch)
 617                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 618                                                       r->fetch_refspec);
 619                if (!r->push)
 620                        r->push = parse_push_refspec(r->push_refspec_nr,
 621                                                     r->push_refspec);
 622                result = fn(r, priv);
 623        }
 624        return result;
 625}
 626
 627void ref_remove_duplicates(struct ref *ref_map)
 628{
 629        struct ref **posn;
 630        struct ref *next;
 631        for (; ref_map; ref_map = ref_map->next) {
 632                if (!ref_map->peer_ref)
 633                        continue;
 634                posn = &ref_map->next;
 635                while (*posn) {
 636                        if ((*posn)->peer_ref &&
 637                            !strcmp((*posn)->peer_ref->name,
 638                                    ref_map->peer_ref->name)) {
 639                                if (strcmp((*posn)->name, ref_map->name))
 640                                        die("%s tracks both %s and %s",
 641                                            ref_map->peer_ref->name,
 642                                            (*posn)->name, ref_map->name);
 643                                next = (*posn)->next;
 644                                free((*posn)->peer_ref);
 645                                free(*posn);
 646                                *posn = next;
 647                        } else {
 648                                posn = &(*posn)->next;
 649                        }
 650                }
 651        }
 652}
 653
 654int remote_has_url(struct remote *remote, const char *url)
 655{
 656        int i;
 657        for (i = 0; i < remote->url_nr; i++) {
 658                if (!strcmp(remote->url[i], url))
 659                        return 1;
 660        }
 661        return 0;
 662}
 663
 664int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 665{
 666        int find_src = refspec->src == NULL;
 667        char *needle, **result;
 668        int i;
 669
 670        if (find_src) {
 671                if (!refspec->dst)
 672                        return error("find_tracking: need either src or dst");
 673                needle = refspec->dst;
 674                result = &refspec->src;
 675        } else {
 676                needle = refspec->src;
 677                result = &refspec->dst;
 678        }
 679
 680        for (i = 0; i < remote->fetch_refspec_nr; i++) {
 681                struct refspec *fetch = &remote->fetch[i];
 682                const char *key = find_src ? fetch->dst : fetch->src;
 683                const char *value = find_src ? fetch->src : fetch->dst;
 684                if (!fetch->dst)
 685                        continue;
 686                if (fetch->pattern) {
 687                        if (!prefixcmp(needle, key) &&
 688                            needle[strlen(key)] == '/') {
 689                                *result = xmalloc(strlen(value) +
 690                                                  strlen(needle) -
 691                                                  strlen(key) + 1);
 692                                strcpy(*result, value);
 693                                strcpy(*result + strlen(value),
 694                                       needle + strlen(key));
 695                                refspec->force = fetch->force;
 696                                return 0;
 697                        }
 698                } else if (!strcmp(needle, key)) {
 699                        *result = xstrdup(value);
 700                        refspec->force = fetch->force;
 701                        return 0;
 702                }
 703        }
 704        return -1;
 705}
 706
 707struct ref *alloc_ref(unsigned namelen)
 708{
 709        struct ref *ret = xmalloc(sizeof(struct ref) + namelen);
 710        memset(ret, 0, sizeof(struct ref) + namelen);
 711        return ret;
 712}
 713
 714struct ref *alloc_ref_from_str(const char* str)
 715{
 716        struct ref *ret = alloc_ref(strlen(str) + 1);
 717        strcpy(ret->name, str);
 718        return ret;
 719}
 720
 721static struct ref *copy_ref(const struct ref *ref)
 722{
 723        struct ref *ret = xmalloc(sizeof(struct ref) + strlen(ref->name) + 1);
 724        memcpy(ret, ref, sizeof(struct ref) + strlen(ref->name) + 1);
 725        ret->next = NULL;
 726        return ret;
 727}
 728
 729struct ref *copy_ref_list(const struct ref *ref)
 730{
 731        struct ref *ret = NULL;
 732        struct ref **tail = &ret;
 733        while (ref) {
 734                *tail = copy_ref(ref);
 735                ref = ref->next;
 736                tail = &((*tail)->next);
 737        }
 738        return ret;
 739}
 740
 741void free_ref(struct ref *ref)
 742{
 743        if (!ref)
 744                return;
 745        free(ref->remote_status);
 746        free(ref->symref);
 747        free(ref);
 748}
 749
 750void free_refs(struct ref *ref)
 751{
 752        struct ref *next;
 753        while (ref) {
 754                next = ref->next;
 755                free(ref->peer_ref);
 756                free_ref(ref);
 757                ref = next;
 758        }
 759}
 760
 761static int count_refspec_match(const char *pattern,
 762                               struct ref *refs,
 763                               struct ref **matched_ref)
 764{
 765        int patlen = strlen(pattern);
 766        struct ref *matched_weak = NULL;
 767        struct ref *matched = NULL;
 768        int weak_match = 0;
 769        int match = 0;
 770
 771        for (weak_match = match = 0; refs; refs = refs->next) {
 772                char *name = refs->name;
 773                int namelen = strlen(name);
 774
 775                if (!refname_match(pattern, name, ref_rev_parse_rules))
 776                        continue;
 777
 778                /* A match is "weak" if it is with refs outside
 779                 * heads or tags, and did not specify the pattern
 780                 * in full (e.g. "refs/remotes/origin/master") or at
 781                 * least from the toplevel (e.g. "remotes/origin/master");
 782                 * otherwise "git push $URL master" would result in
 783                 * ambiguity between remotes/origin/master and heads/master
 784                 * at the remote site.
 785                 */
 786                if (namelen != patlen &&
 787                    patlen != namelen - 5 &&
 788                    prefixcmp(name, "refs/heads/") &&
 789                    prefixcmp(name, "refs/tags/")) {
 790                        /* We want to catch the case where only weak
 791                         * matches are found and there are multiple
 792                         * matches, and where more than one strong
 793                         * matches are found, as ambiguous.  One
 794                         * strong match with zero or more weak matches
 795                         * are acceptable as a unique match.
 796                         */
 797                        matched_weak = refs;
 798                        weak_match++;
 799                }
 800                else {
 801                        matched = refs;
 802                        match++;
 803                }
 804        }
 805        if (!matched) {
 806                *matched_ref = matched_weak;
 807                return weak_match;
 808        }
 809        else {
 810                *matched_ref = matched;
 811                return match;
 812        }
 813}
 814
 815static void tail_link_ref(struct ref *ref, struct ref ***tail)
 816{
 817        **tail = ref;
 818        while (ref->next)
 819                ref = ref->next;
 820        *tail = &ref->next;
 821}
 822
 823static struct ref *try_explicit_object_name(const char *name)
 824{
 825        unsigned char sha1[20];
 826        struct ref *ref;
 827
 828        if (!*name) {
 829                ref = alloc_ref(20);
 830                strcpy(ref->name, "(delete)");
 831                hashclr(ref->new_sha1);
 832                return ref;
 833        }
 834        if (get_sha1(name, sha1))
 835                return NULL;
 836        ref = alloc_ref_from_str(name);
 837        hashcpy(ref->new_sha1, sha1);
 838        return ref;
 839}
 840
 841static struct ref *make_linked_ref(const char *name, struct ref ***tail)
 842{
 843        struct ref *ret = alloc_ref_from_str(name);
 844        tail_link_ref(ret, tail);
 845        return ret;
 846}
 847
 848static char *guess_ref(const char *name, struct ref *peer)
 849{
 850        struct strbuf buf = STRBUF_INIT;
 851        unsigned char sha1[20];
 852
 853        const char *r = resolve_ref(peer->name, sha1, 1, NULL);
 854        if (!r)
 855                return NULL;
 856
 857        if (!prefixcmp(r, "refs/heads/"))
 858                strbuf_addstr(&buf, "refs/heads/");
 859        else if (!prefixcmp(r, "refs/tags/"))
 860                strbuf_addstr(&buf, "refs/tags/");
 861        else
 862                return NULL;
 863
 864        strbuf_addstr(&buf, name);
 865        return strbuf_detach(&buf, NULL);
 866}
 867
 868static int match_explicit(struct ref *src, struct ref *dst,
 869                          struct ref ***dst_tail,
 870                          struct refspec *rs,
 871                          int errs)
 872{
 873        struct ref *matched_src, *matched_dst;
 874
 875        const char *dst_value = rs->dst;
 876        char *dst_guess;
 877
 878        if (rs->pattern || rs->matching)
 879                return errs;
 880
 881        matched_src = matched_dst = NULL;
 882        switch (count_refspec_match(rs->src, src, &matched_src)) {
 883        case 1:
 884                break;
 885        case 0:
 886                /* The source could be in the get_sha1() format
 887                 * not a reference name.  :refs/other is a
 888                 * way to delete 'other' ref at the remote end.
 889                 */
 890                matched_src = try_explicit_object_name(rs->src);
 891                if (!matched_src)
 892                        error("src refspec %s does not match any.", rs->src);
 893                break;
 894        default:
 895                matched_src = NULL;
 896                error("src refspec %s matches more than one.", rs->src);
 897                break;
 898        }
 899
 900        if (!matched_src)
 901                errs = 1;
 902
 903        if (!dst_value) {
 904                unsigned char sha1[20];
 905                int flag;
 906
 907                if (!matched_src)
 908                        return errs;
 909                dst_value = resolve_ref(matched_src->name, sha1, 1, &flag);
 910                if (!dst_value ||
 911                    ((flag & REF_ISSYMREF) &&
 912                     prefixcmp(dst_value, "refs/heads/")))
 913                        die("%s cannot be resolved to branch.",
 914                            matched_src->name);
 915        }
 916
 917        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
 918        case 1:
 919                break;
 920        case 0:
 921                if (!memcmp(dst_value, "refs/", 5))
 922                        matched_dst = make_linked_ref(dst_value, dst_tail);
 923                else if((dst_guess = guess_ref(dst_value, matched_src)))
 924                        matched_dst = make_linked_ref(dst_guess, dst_tail);
 925                else
 926                        error("unable to push to unqualified destination: %s\n"
 927                              "The destination refspec neither matches an "
 928                              "existing ref on the remote nor\n"
 929                              "begins with refs/, and we are unable to "
 930                              "guess a prefix based on the source ref.",
 931                              dst_value);
 932                break;
 933        default:
 934                matched_dst = NULL;
 935                error("dst refspec %s matches more than one.",
 936                      dst_value);
 937                break;
 938        }
 939        if (errs || !matched_dst)
 940                return 1;
 941        if (matched_dst->peer_ref) {
 942                errs = 1;
 943                error("dst ref %s receives from more than one src.",
 944                      matched_dst->name);
 945        }
 946        else {
 947                matched_dst->peer_ref = matched_src;
 948                matched_dst->force = rs->force;
 949        }
 950        return errs;
 951}
 952
 953static int match_explicit_refs(struct ref *src, struct ref *dst,
 954                               struct ref ***dst_tail, struct refspec *rs,
 955                               int rs_nr)
 956{
 957        int i, errs;
 958        for (i = errs = 0; i < rs_nr; i++)
 959                errs |= match_explicit(src, dst, dst_tail, &rs[i], errs);
 960        return -errs;
 961}
 962
 963static const struct refspec *check_pattern_match(const struct refspec *rs,
 964                                                 int rs_nr,
 965                                                 const struct ref *src)
 966{
 967        int i;
 968        int matching_refs = -1;
 969        for (i = 0; i < rs_nr; i++) {
 970                if (rs[i].matching &&
 971                    (matching_refs == -1 || rs[i].force)) {
 972                        matching_refs = i;
 973                        continue;
 974                }
 975
 976                if (rs[i].pattern &&
 977                    !prefixcmp(src->name, rs[i].src) &&
 978                    src->name[strlen(rs[i].src)] == '/')
 979                        return rs + i;
 980        }
 981        if (matching_refs != -1)
 982                return rs + matching_refs;
 983        else
 984                return NULL;
 985}
 986
 987/*
 988 * Note. This is used only by "push"; refspec matching rules for
 989 * push and fetch are subtly different, so do not try to reuse it
 990 * without thinking.
 991 */
 992int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 993               int nr_refspec, const char **refspec, int flags)
 994{
 995        struct refspec *rs;
 996        int send_all = flags & MATCH_REFS_ALL;
 997        int send_mirror = flags & MATCH_REFS_MIRROR;
 998        static const char *default_refspec[] = { ":", 0 };
 999
1000        if (!nr_refspec) {
1001                nr_refspec = 1;
1002                refspec = default_refspec;
1003        }
1004        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1005        if (match_explicit_refs(src, dst, dst_tail, rs, nr_refspec))
1006                return -1;
1007
1008        /* pick the remainder */
1009        for ( ; src; src = src->next) {
1010                struct ref *dst_peer;
1011                const struct refspec *pat = NULL;
1012                char *dst_name;
1013                if (src->peer_ref)
1014                        continue;
1015
1016                pat = check_pattern_match(rs, nr_refspec, src);
1017                if (!pat)
1018                        continue;
1019
1020                if (pat->matching) {
1021                        /*
1022                         * "matching refs"; traditionally we pushed everything
1023                         * including refs outside refs/heads/ hierarchy, but
1024                         * that does not make much sense these days.
1025                         */
1026                        if (!send_mirror && prefixcmp(src->name, "refs/heads/"))
1027                                continue;
1028                        dst_name = xstrdup(src->name);
1029
1030                } else {
1031                        const char *dst_side = pat->dst ? pat->dst : pat->src;
1032                        dst_name = xmalloc(strlen(dst_side) +
1033                                           strlen(src->name) -
1034                                           strlen(pat->src) + 2);
1035                        strcpy(dst_name, dst_side);
1036                        strcat(dst_name, src->name + strlen(pat->src));
1037                }
1038                dst_peer = find_ref_by_name(dst, dst_name);
1039                if (dst_peer) {
1040                        if (dst_peer->peer_ref)
1041                                /* We're already sending something to this ref. */
1042                                goto free_name;
1043
1044                } else {
1045                        if (pat->matching && !(send_all || send_mirror))
1046                                /*
1047                                 * Remote doesn't have it, and we have no
1048                                 * explicit pattern, and we don't have
1049                                 * --all nor --mirror.
1050                                 */
1051                                goto free_name;
1052
1053                        /* Create a new one and link it */
1054                        dst_peer = make_linked_ref(dst_name, dst_tail);
1055                        hashcpy(dst_peer->new_sha1, src->new_sha1);
1056                }
1057                dst_peer->peer_ref = src;
1058                dst_peer->force = pat->force;
1059        free_name:
1060                free(dst_name);
1061        }
1062        return 0;
1063}
1064
1065struct branch *branch_get(const char *name)
1066{
1067        struct branch *ret;
1068
1069        read_config();
1070        if (!name || !*name || !strcmp(name, "HEAD"))
1071                ret = current_branch;
1072        else
1073                ret = make_branch(name, 0);
1074        if (ret && ret->remote_name) {
1075                ret->remote = remote_get(ret->remote_name);
1076                if (ret->merge_nr) {
1077                        int i;
1078                        ret->merge = xcalloc(sizeof(*ret->merge),
1079                                             ret->merge_nr);
1080                        for (i = 0; i < ret->merge_nr; i++) {
1081                                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1082                                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1083                                remote_find_tracking(ret->remote,
1084                                                     ret->merge[i]);
1085                        }
1086                }
1087        }
1088        return ret;
1089}
1090
1091int branch_has_merge_config(struct branch *branch)
1092{
1093        return branch && !!branch->merge;
1094}
1095
1096int branch_merge_matches(struct branch *branch,
1097                                 int i,
1098                                 const char *refname)
1099{
1100        if (!branch || i < 0 || i >= branch->merge_nr)
1101                return 0;
1102        return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
1103}
1104
1105static struct ref *get_expanded_map(const struct ref *remote_refs,
1106                                    const struct refspec *refspec)
1107{
1108        const struct ref *ref;
1109        struct ref *ret = NULL;
1110        struct ref **tail = &ret;
1111
1112        int remote_prefix_len = strlen(refspec->src);
1113        int local_prefix_len = strlen(refspec->dst);
1114
1115        for (ref = remote_refs; ref; ref = ref->next) {
1116                if (strchr(ref->name, '^'))
1117                        continue; /* a dereference item */
1118                if (!prefixcmp(ref->name, refspec->src)) {
1119                        const char *match;
1120                        struct ref *cpy = copy_ref(ref);
1121                        match = ref->name + remote_prefix_len;
1122
1123                        cpy->peer_ref = alloc_ref(local_prefix_len +
1124                                                  strlen(match) + 1);
1125                        sprintf(cpy->peer_ref->name, "%s%s",
1126                                refspec->dst, match);
1127                        if (refspec->force)
1128                                cpy->peer_ref->force = 1;
1129                        *tail = cpy;
1130                        tail = &cpy->next;
1131                }
1132        }
1133
1134        return ret;
1135}
1136
1137static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1138{
1139        const struct ref *ref;
1140        for (ref = refs; ref; ref = ref->next) {
1141                if (refname_match(name, ref->name, ref_fetch_rules))
1142                        return ref;
1143        }
1144        return NULL;
1145}
1146
1147struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1148{
1149        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1150
1151        if (!ref)
1152                return NULL;
1153
1154        return copy_ref(ref);
1155}
1156
1157static struct ref *get_local_ref(const char *name)
1158{
1159        struct ref *ret;
1160        if (!name)
1161                return NULL;
1162
1163        if (!prefixcmp(name, "refs/")) {
1164                return alloc_ref_from_str(name);
1165        }
1166
1167        if (!prefixcmp(name, "heads/") ||
1168            !prefixcmp(name, "tags/") ||
1169            !prefixcmp(name, "remotes/")) {
1170                ret = alloc_ref(strlen(name) + 6);
1171                sprintf(ret->name, "refs/%s", name);
1172                return ret;
1173        }
1174
1175        ret = alloc_ref(strlen(name) + 12);
1176        sprintf(ret->name, "refs/heads/%s", name);
1177        return ret;
1178}
1179
1180int get_fetch_map(const struct ref *remote_refs,
1181                  const struct refspec *refspec,
1182                  struct ref ***tail,
1183                  int missing_ok)
1184{
1185        struct ref *ref_map, **rmp;
1186
1187        if (refspec->pattern) {
1188                ref_map = get_expanded_map(remote_refs, refspec);
1189        } else {
1190                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1191
1192                ref_map = get_remote_ref(remote_refs, name);
1193                if (!missing_ok && !ref_map)
1194                        die("Couldn't find remote ref %s", name);
1195                if (ref_map) {
1196                        ref_map->peer_ref = get_local_ref(refspec->dst);
1197                        if (ref_map->peer_ref && refspec->force)
1198                                ref_map->peer_ref->force = 1;
1199                }
1200        }
1201
1202        for (rmp = &ref_map; *rmp; ) {
1203                if ((*rmp)->peer_ref) {
1204                        int st = check_ref_format((*rmp)->peer_ref->name + 5);
1205                        if (st && st != CHECK_REF_FORMAT_ONELEVEL) {
1206                                struct ref *ignore = *rmp;
1207                                error("* Ignoring funny ref '%s' locally",
1208                                      (*rmp)->peer_ref->name);
1209                                *rmp = (*rmp)->next;
1210                                free(ignore->peer_ref);
1211                                free(ignore);
1212                                continue;
1213                        }
1214                }
1215                rmp = &((*rmp)->next);
1216        }
1217
1218        if (ref_map)
1219                tail_link_ref(ref_map, tail);
1220
1221        return 0;
1222}
1223
1224int resolve_remote_symref(struct ref *ref, struct ref *list)
1225{
1226        if (!ref->symref)
1227                return 0;
1228        for (; list; list = list->next)
1229                if (!strcmp(ref->symref, list->name)) {
1230                        hashcpy(ref->old_sha1, list->old_sha1);
1231                        return 0;
1232                }
1233        return 1;
1234}