Andrew's git / gitweb.git / remote.c
?
remote.con commit Allow the built-in exec path to be relative to the command invocation path (49fa65a)
   1#include "cache.h"
   2#include "remote.h"
   3#include "refs.h"
   4#include "commit.h"
   5#include "diff.h"
   6#include "revision.h"
   7
   8static struct refspec s_tag_refspec = {
   9        0,
  10        1,
  11        0,
  12        "refs/tags/",
  13        "refs/tags/"
  14};
  15
  16const struct refspec *tag_refspec = &s_tag_refspec;
  17
  18struct counted_string {
  19        size_t len;
  20        const char *s;
  21};
  22struct rewrite {
  23        const char *base;
  24        size_t baselen;
  25        struct counted_string *instead_of;
  26        int instead_of_nr;
  27        int instead_of_alloc;
  28};
  29
  30static struct remote **remotes;
  31static int remotes_alloc;
  32static int remotes_nr;
  33
  34static struct branch **branches;
  35static int branches_alloc;
  36static int branches_nr;
  37
  38static struct branch *current_branch;
  39static const char *default_remote_name;
  40
  41static struct rewrite **rewrite;
  42static int rewrite_alloc;
  43static int rewrite_nr;
  44
  45#define BUF_SIZE (2048)
  46static char buffer[BUF_SIZE];
  47
  48static const char *alias_url(const char *url)
  49{
  50        int i, j;
  51        char *ret;
  52        struct counted_string *longest;
  53        int longest_i;
  54
  55        longest = NULL;
  56        longest_i = -1;
  57        for (i = 0; i < rewrite_nr; i++) {
  58                if (!rewrite[i])
  59                        continue;
  60                for (j = 0; j < rewrite[i]->instead_of_nr; j++) {
  61                        if (!prefixcmp(url, rewrite[i]->instead_of[j].s) &&
  62                            (!longest ||
  63                             longest->len < rewrite[i]->instead_of[j].len)) {
  64                                longest = &(rewrite[i]->instead_of[j]);
  65                                longest_i = i;
  66                        }
  67                }
  68        }
  69        if (!longest)
  70                return url;
  71
  72        ret = malloc(rewrite[longest_i]->baselen +
  73                     (strlen(url) - longest->len) + 1);
  74        strcpy(ret, rewrite[longest_i]->base);
  75        strcpy(ret + rewrite[longest_i]->baselen, url + longest->len);
  76        return ret;
  77}
  78
  79static void add_push_refspec(struct remote *remote, const char *ref)
  80{
  81        ALLOC_GROW(remote->push_refspec,
  82                   remote->push_refspec_nr + 1,
  83                   remote->push_refspec_alloc);
  84        remote->push_refspec[remote->push_refspec_nr++] = ref;
  85}
  86
  87static void add_fetch_refspec(struct remote *remote, const char *ref)
  88{
  89        ALLOC_GROW(remote->fetch_refspec,
  90                   remote->fetch_refspec_nr + 1,
  91                   remote->fetch_refspec_alloc);
  92        remote->fetch_refspec[remote->fetch_refspec_nr++] = ref;
  93}
  94
  95static void add_url(struct remote *remote, const char *url)
  96{
  97        ALLOC_GROW(remote->url, remote->url_nr + 1, remote->url_alloc);
  98        remote->url[remote->url_nr++] = url;
  99}
 100
 101static void add_url_alias(struct remote *remote, const char *url)
 102{
 103        add_url(remote, alias_url(url));
 104}
 105
 106static struct remote *make_remote(const char *name, int len)
 107{
 108        struct remote *ret;
 109        int i;
 110
 111        for (i = 0; i < remotes_nr; i++) {
 112                if (len ? (!strncmp(name, remotes[i]->name, len) &&
 113                           !remotes[i]->name[len]) :
 114                    !strcmp(name, remotes[i]->name))
 115                        return remotes[i];
 116        }
 117
 118        ret = xcalloc(1, sizeof(struct remote));
 119        ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 120        remotes[remotes_nr++] = ret;
 121        if (len)
 122                ret->name = xstrndup(name, len);
 123        else
 124                ret->name = xstrdup(name);
 125        return ret;
 126}
 127
 128static void add_merge(struct branch *branch, const char *name)
 129{
 130        ALLOC_GROW(branch->merge_name, branch->merge_nr + 1,
 131                   branch->merge_alloc);
 132        branch->merge_name[branch->merge_nr++] = name;
 133}
 134
 135static struct branch *make_branch(const char *name, int len)
 136{
 137        struct branch *ret;
 138        int i;
 139        char *refname;
 140
 141        for (i = 0; i < branches_nr; i++) {
 142                if (len ? (!strncmp(name, branches[i]->name, len) &&
 143                           !branches[i]->name[len]) :
 144                    !strcmp(name, branches[i]->name))
 145                        return branches[i];
 146        }
 147
 148        ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 149        ret = xcalloc(1, sizeof(struct branch));
 150        branches[branches_nr++] = ret;
 151        if (len)
 152                ret->name = xstrndup(name, len);
 153        else
 154                ret->name = xstrdup(name);
 155        refname = malloc(strlen(name) + strlen("refs/heads/") + 1);
 156        strcpy(refname, "refs/heads/");
 157        strcpy(refname + strlen("refs/heads/"), ret->name);
 158        ret->refname = refname;
 159
 160        return ret;
 161}
 162
 163static struct rewrite *make_rewrite(const char *base, int len)
 164{
 165        struct rewrite *ret;
 166        int i;
 167
 168        for (i = 0; i < rewrite_nr; i++) {
 169                if (len
 170                    ? (len == rewrite[i]->baselen &&
 171                       !strncmp(base, rewrite[i]->base, len))
 172                    : !strcmp(base, rewrite[i]->base))
 173                        return rewrite[i];
 174        }
 175
 176        ALLOC_GROW(rewrite, rewrite_nr + 1, rewrite_alloc);
 177        ret = xcalloc(1, sizeof(struct rewrite));
 178        rewrite[rewrite_nr++] = ret;
 179        if (len) {
 180                ret->base = xstrndup(base, len);
 181                ret->baselen = len;
 182        }
 183        else {
 184                ret->base = xstrdup(base);
 185                ret->baselen = strlen(base);
 186        }
 187        return ret;
 188}
 189
 190static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 191{
 192        ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 193        rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 194        rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 195        rewrite->instead_of_nr++;
 196}
 197
 198static void read_remotes_file(struct remote *remote)
 199{
 200        FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
 201
 202        if (!f)
 203                return;
 204        while (fgets(buffer, BUF_SIZE, f)) {
 205                int value_list;
 206                char *s, *p;
 207
 208                if (!prefixcmp(buffer, "URL:")) {
 209                        value_list = 0;
 210                        s = buffer + 4;
 211                } else if (!prefixcmp(buffer, "Push:")) {
 212                        value_list = 1;
 213                        s = buffer + 5;
 214                } else if (!prefixcmp(buffer, "Pull:")) {
 215                        value_list = 2;
 216                        s = buffer + 5;
 217                } else
 218                        continue;
 219
 220                while (isspace(*s))
 221                        s++;
 222                if (!*s)
 223                        continue;
 224
 225                p = s + strlen(s);
 226                while (isspace(p[-1]))
 227                        *--p = 0;
 228
 229                switch (value_list) {
 230                case 0:
 231                        add_url_alias(remote, xstrdup(s));
 232                        break;
 233                case 1:
 234                        add_push_refspec(remote, xstrdup(s));
 235                        break;
 236                case 2:
 237                        add_fetch_refspec(remote, xstrdup(s));
 238                        break;
 239                }
 240        }
 241        fclose(f);
 242}
 243
 244static void read_branches_file(struct remote *remote)
 245{
 246        const char *slash = strchr(remote->name, '/');
 247        char *frag;
 248        struct strbuf branch;
 249        int n = slash ? slash - remote->name : 1000;
 250        FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 251        char *s, *p;
 252        int len;
 253
 254        if (!f)
 255                return;
 256        s = fgets(buffer, BUF_SIZE, f);
 257        fclose(f);
 258        if (!s)
 259                return;
 260        while (isspace(*s))
 261                s++;
 262        if (!*s)
 263                return;
 264        p = s + strlen(s);
 265        while (isspace(p[-1]))
 266                *--p = 0;
 267        len = p - s;
 268        if (slash)
 269                len += strlen(slash);
 270        p = xmalloc(len + 1);
 271        strcpy(p, s);
 272        if (slash)
 273                strcat(p, slash);
 274
 275        /*
 276         * With "slash", e.g. "git fetch jgarzik/netdev-2.6" when
 277         * reading from $GIT_DIR/branches/jgarzik fetches "HEAD" from
 278         * the partial URL obtained from the branches file plus
 279         * "/netdev-2.6" and does not store it in any tracking ref.
 280         * #branch specifier in the file is ignored.
 281         *
 282         * Otherwise, the branches file would have URL and optionally
 283         * #branch specified.  The "master" (or specified) branch is
 284         * fetched and stored in the local branch of the same name.
 285         */
 286        strbuf_init(&branch, 0);
 287        frag = strchr(p, '#');
 288        if (frag) {
 289                *(frag++) = '\0';
 290                strbuf_addf(&branch, "refs/heads/%s", frag);
 291        } else
 292                strbuf_addstr(&branch, "refs/heads/master");
 293        if (!slash) {
 294                strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 295        } else {
 296                strbuf_reset(&branch);
 297                strbuf_addstr(&branch, "HEAD:");
 298        }
 299        add_url_alias(remote, p);
 300        add_fetch_refspec(remote, strbuf_detach(&branch, 0));
 301        remote->fetch_tags = 1; /* always auto-follow */
 302}
 303
 304static int handle_config(const char *key, const char *value, void *cb)
 305{
 306        const char *name;
 307        const char *subkey;
 308        struct remote *remote;
 309        struct branch *branch;
 310        if (!prefixcmp(key, "branch.")) {
 311                name = key + 7;
 312                subkey = strrchr(name, '.');
 313                if (!subkey)
 314                        return 0;
 315                branch = make_branch(name, subkey - name);
 316                if (!strcmp(subkey, ".remote")) {
 317                        if (!value)
 318                                return config_error_nonbool(key);
 319                        branch->remote_name = xstrdup(value);
 320                        if (branch == current_branch)
 321                                default_remote_name = branch->remote_name;
 322                } else if (!strcmp(subkey, ".merge")) {
 323                        if (!value)
 324                                return config_error_nonbool(key);
 325                        add_merge(branch, xstrdup(value));
 326                }
 327                return 0;
 328        }
 329        if (!prefixcmp(key, "url.")) {
 330                struct rewrite *rewrite;
 331                name = key + 4;
 332                subkey = strrchr(name, '.');
 333                if (!subkey)
 334                        return 0;
 335                rewrite = make_rewrite(name, subkey - name);
 336                if (!strcmp(subkey, ".insteadof")) {
 337                        if (!value)
 338                                return config_error_nonbool(key);
 339                        add_instead_of(rewrite, xstrdup(value));
 340                }
 341        }
 342        if (prefixcmp(key,  "remote."))
 343                return 0;
 344        name = key + 7;
 345        subkey = strrchr(name, '.');
 346        if (!subkey)
 347                return error("Config with no key for remote %s", name);
 348        if (*subkey == '/') {
 349                warning("Config remote shorthand cannot begin with '/': %s", name);
 350                return 0;
 351        }
 352        remote = make_remote(name, subkey - name);
 353        if (!strcmp(subkey, ".mirror"))
 354                remote->mirror = git_config_bool(key, value);
 355        else if (!strcmp(subkey, ".skipdefaultupdate"))
 356                remote->skip_default_update = git_config_bool(key, value);
 357
 358        else if (!strcmp(subkey, ".url")) {
 359                const char *v;
 360                if (git_config_string(&v, key, value))
 361                        return -1;
 362                add_url(remote, v);
 363        } else if (!strcmp(subkey, ".push")) {
 364                const char *v;
 365                if (git_config_string(&v, key, value))
 366                        return -1;
 367                add_push_refspec(remote, v);
 368        } else if (!strcmp(subkey, ".fetch")) {
 369                const char *v;
 370                if (git_config_string(&v, key, value))
 371                        return -1;
 372                add_fetch_refspec(remote, v);
 373        } else if (!strcmp(subkey, ".receivepack")) {
 374                const char *v;
 375                if (git_config_string(&v, key, value))
 376                        return -1;
 377                if (!remote->receivepack)
 378                        remote->receivepack = v;
 379                else
 380                        error("more than one receivepack given, using the first");
 381        } else if (!strcmp(subkey, ".uploadpack")) {
 382                const char *v;
 383                if (git_config_string(&v, key, value))
 384                        return -1;
 385                if (!remote->uploadpack)
 386                        remote->uploadpack = v;
 387                else
 388                        error("more than one uploadpack given, using the first");
 389        } else if (!strcmp(subkey, ".tagopt")) {
 390                if (!strcmp(value, "--no-tags"))
 391                        remote->fetch_tags = -1;
 392        } else if (!strcmp(subkey, ".proxy")) {
 393                return git_config_string((const char **)&remote->http_proxy,
 394                                         key, value);
 395        }
 396        return 0;
 397}
 398
 399static void alias_all_urls(void)
 400{
 401        int i, j;
 402        for (i = 0; i < remotes_nr; i++) {
 403                if (!remotes[i])
 404                        continue;
 405                for (j = 0; j < remotes[i]->url_nr; j++) {
 406                        remotes[i]->url[j] = alias_url(remotes[i]->url[j]);
 407                }
 408        }
 409}
 410
 411static void read_config(void)
 412{
 413        unsigned char sha1[20];
 414        const char *head_ref;
 415        int flag;
 416        if (default_remote_name) // did this already
 417                return;
 418        default_remote_name = xstrdup("origin");
 419        current_branch = NULL;
 420        head_ref = resolve_ref("HEAD", sha1, 0, &flag);
 421        if (head_ref && (flag & REF_ISSYMREF) &&
 422            !prefixcmp(head_ref, "refs/heads/")) {
 423                current_branch =
 424                        make_branch(head_ref + strlen("refs/heads/"), 0);
 425        }
 426        git_config(handle_config, NULL);
 427        alias_all_urls();
 428}
 429
 430static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 431{
 432        int i;
 433        int st;
 434        struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 435
 436        for (i = 0; i < nr_refspec; i++) {
 437                size_t llen, rlen;
 438                int is_glob;
 439                const char *lhs, *rhs;
 440
 441                llen = rlen = is_glob = 0;
 442
 443                lhs = refspec[i];
 444                if (*lhs == '+') {
 445                        rs[i].force = 1;
 446                        lhs++;
 447                }
 448
 449                rhs = strrchr(lhs, ':');
 450
 451                /*
 452                 * Before going on, special case ":" (or "+:") as a refspec
 453                 * for matching refs.
 454                 */
 455                if (!fetch && rhs == lhs && rhs[1] == '\0') {
 456                        rs[i].matching = 1;
 457                        continue;
 458                }
 459
 460                if (rhs) {
 461                        rhs++;
 462                        rlen = strlen(rhs);
 463                        is_glob = (2 <= rlen && !strcmp(rhs + rlen - 2, "/*"));
 464                        if (is_glob)
 465                                rlen -= 2;
 466                        rs[i].dst = xstrndup(rhs, rlen);
 467                }
 468
 469                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 470                if (2 <= llen && !memcmp(lhs + llen - 2, "/*", 2)) {
 471                        if ((rhs && !is_glob) || (!rhs && fetch))
 472                                goto invalid;
 473                        is_glob = 1;
 474                        llen -= 2;
 475                } else if (rhs && is_glob) {
 476                        goto invalid;
 477                }
 478
 479                rs[i].pattern = is_glob;
 480                rs[i].src = xstrndup(lhs, llen);
 481
 482                if (fetch) {
 483                        /*
 484                         * LHS
 485                         * - empty is allowed; it means HEAD.
 486                         * - otherwise it must be a valid looking ref.
 487                         */
 488                        if (!*rs[i].src)
 489                                ; /* empty is ok */
 490                        else {
 491                                st = check_ref_format(rs[i].src);
 492                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 493                                        goto invalid;
 494                        }
 495                        /*
 496                         * RHS
 497                         * - missing is ok, and is same as empty.
 498                         * - empty is ok; it means not to store.
 499                         * - otherwise it must be a valid looking ref.
 500                         */
 501                        if (!rs[i].dst) {
 502                                ; /* ok */
 503                        } else if (!*rs[i].dst) {
 504                                ; /* ok */
 505                        } else {
 506                                st = check_ref_format(rs[i].dst);
 507                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 508                                        goto invalid;
 509                        }
 510                } else {
 511                        /*
 512                         * LHS
 513                         * - empty is allowed; it means delete.
 514                         * - when wildcarded, it must be a valid looking ref.
 515                         * - otherwise, it must be an extended SHA-1, but
 516                         *   there is no existing way to validate this.
 517                         */
 518                        if (!*rs[i].src)
 519                                ; /* empty is ok */
 520                        else if (is_glob) {
 521                                st = check_ref_format(rs[i].src);
 522                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 523                                        goto invalid;
 524                        }
 525                        else
 526                                ; /* anything goes, for now */
 527                        /*
 528                         * RHS
 529                         * - missing is allowed, but LHS then must be a
 530                         *   valid looking ref.
 531                         * - empty is not allowed.
 532                         * - otherwise it must be a valid looking ref.
 533                         */
 534                        if (!rs[i].dst) {
 535                                st = check_ref_format(rs[i].src);
 536                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 537                                        goto invalid;
 538                        } else if (!*rs[i].dst) {
 539                                goto invalid;
 540                        } else {
 541                                st = check_ref_format(rs[i].dst);
 542                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 543                                        goto invalid;
 544                        }
 545                }
 546        }
 547        return rs;
 548
 549 invalid:
 550        if (verify) {
 551                free(rs);
 552                return NULL;
 553        }
 554        die("Invalid refspec '%s'", refspec[i]);
 555}
 556
 557int valid_fetch_refspec(const char *fetch_refspec_str)
 558{
 559        const char *fetch_refspec[] = { fetch_refspec_str };
 560        struct refspec *refspec;
 561
 562        refspec = parse_refspec_internal(1, fetch_refspec, 1, 1);
 563        if (refspec)
 564                free(refspec);
 565        return !!refspec;
 566}
 567
 568struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 569{
 570        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 571}
 572
 573struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 574{
 575        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 576}
 577
 578static int valid_remote_nick(const char *name)
 579{
 580        if (!name[0] || /* not empty */
 581            (name[0] == '.' && /* not "." */
 582             (!name[1] || /* not ".." */
 583              (name[1] == '.' && !name[2]))))
 584                return 0;
 585        return !strchr(name, '/'); /* no slash */
 586}
 587
 588struct remote *remote_get(const char *name)
 589{
 590        struct remote *ret;
 591
 592        read_config();
 593        if (!name)
 594                name = default_remote_name;
 595        ret = make_remote(name, 0);
 596        if (valid_remote_nick(name)) {
 597                if (!ret->url)
 598                        read_remotes_file(ret);
 599                if (!ret->url)
 600                        read_branches_file(ret);
 601        }
 602        if (!ret->url)
 603                add_url_alias(ret, name);
 604        if (!ret->url)
 605                return NULL;
 606        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 607        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 608        return ret;
 609}
 610
 611int for_each_remote(each_remote_fn fn, void *priv)
 612{
 613        int i, result = 0;
 614        read_config();
 615        for (i = 0; i < remotes_nr && !result; i++) {
 616                struct remote *r = remotes[i];
 617                if (!r)
 618                        continue;
 619                if (!r->fetch)
 620                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 621                                                       r->fetch_refspec);
 622                if (!r->push)
 623                        r->push = parse_push_refspec(r->push_refspec_nr,
 624                                                     r->push_refspec);
 625                result = fn(r, priv);
 626        }
 627        return result;
 628}
 629
 630void ref_remove_duplicates(struct ref *ref_map)
 631{
 632        struct ref **posn;
 633        struct ref *next;
 634        for (; ref_map; ref_map = ref_map->next) {
 635                if (!ref_map->peer_ref)
 636                        continue;
 637                posn = &ref_map->next;
 638                while (*posn) {
 639                        if ((*posn)->peer_ref &&
 640                            !strcmp((*posn)->peer_ref->name,
 641                                    ref_map->peer_ref->name)) {
 642                                if (strcmp((*posn)->name, ref_map->name))
 643                                        die("%s tracks both %s and %s",
 644                                            ref_map->peer_ref->name,
 645                                            (*posn)->name, ref_map->name);
 646                                next = (*posn)->next;
 647                                free((*posn)->peer_ref);
 648                                free(*posn);
 649                                *posn = next;
 650                        } else {
 651                                posn = &(*posn)->next;
 652                        }
 653                }
 654        }
 655}
 656
 657int remote_has_url(struct remote *remote, const char *url)
 658{
 659        int i;
 660        for (i = 0; i < remote->url_nr; i++) {
 661                if (!strcmp(remote->url[i], url))
 662                        return 1;
 663        }
 664        return 0;
 665}
 666
 667int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 668{
 669        int find_src = refspec->src == NULL;
 670        char *needle, **result;
 671        int i;
 672
 673        if (find_src) {
 674                if (!refspec->dst)
 675                        return error("find_tracking: need either src or dst");
 676                needle = refspec->dst;
 677                result = &refspec->src;
 678        } else {
 679                needle = refspec->src;
 680                result = &refspec->dst;
 681        }
 682
 683        for (i = 0; i < remote->fetch_refspec_nr; i++) {
 684                struct refspec *fetch = &remote->fetch[i];
 685                const char *key = find_src ? fetch->dst : fetch->src;
 686                const char *value = find_src ? fetch->src : fetch->dst;
 687                if (!fetch->dst)
 688                        continue;
 689                if (fetch->pattern) {
 690                        if (!prefixcmp(needle, key) &&
 691                            needle[strlen(key)] == '/') {
 692                                *result = xmalloc(strlen(value) +
 693                                                  strlen(needle) -
 694                                                  strlen(key) + 1);
 695                                strcpy(*result, value);
 696                                strcpy(*result + strlen(value),
 697                                       needle + strlen(key));
 698                                refspec->force = fetch->force;
 699                                return 0;
 700                        }
 701                } else if (!strcmp(needle, key)) {
 702                        *result = xstrdup(value);
 703                        refspec->force = fetch->force;
 704                        return 0;
 705                }
 706        }
 707        return -1;
 708}
 709
 710struct ref *alloc_ref(unsigned namelen)
 711{
 712        struct ref *ret = xmalloc(sizeof(struct ref) + namelen);
 713        memset(ret, 0, sizeof(struct ref) + namelen);
 714        return ret;
 715}
 716
 717struct ref *alloc_ref_from_str(const char* str)
 718{
 719        struct ref *ret = alloc_ref(strlen(str) + 1);
 720        strcpy(ret->name, str);
 721        return ret;
 722}
 723
 724static struct ref *copy_ref(const struct ref *ref)
 725{
 726        struct ref *ret = xmalloc(sizeof(struct ref) + strlen(ref->name) + 1);
 727        memcpy(ret, ref, sizeof(struct ref) + strlen(ref->name) + 1);
 728        ret->next = NULL;
 729        return ret;
 730}
 731
 732struct ref *copy_ref_list(const struct ref *ref)
 733{
 734        struct ref *ret = NULL;
 735        struct ref **tail = &ret;
 736        while (ref) {
 737                *tail = copy_ref(ref);
 738                ref = ref->next;
 739                tail = &((*tail)->next);
 740        }
 741        return ret;
 742}
 743
 744void free_ref(struct ref *ref)
 745{
 746        if (!ref)
 747                return;
 748        free(ref->remote_status);
 749        free(ref->symref);
 750        free(ref);
 751}
 752
 753void free_refs(struct ref *ref)
 754{
 755        struct ref *next;
 756        while (ref) {
 757                next = ref->next;
 758                free(ref->peer_ref);
 759                free_ref(ref);
 760                ref = next;
 761        }
 762}
 763
 764static int count_refspec_match(const char *pattern,
 765                               struct ref *refs,
 766                               struct ref **matched_ref)
 767{
 768        int patlen = strlen(pattern);
 769        struct ref *matched_weak = NULL;
 770        struct ref *matched = NULL;
 771        int weak_match = 0;
 772        int match = 0;
 773
 774        for (weak_match = match = 0; refs; refs = refs->next) {
 775                char *name = refs->name;
 776                int namelen = strlen(name);
 777
 778                if (!refname_match(pattern, name, ref_rev_parse_rules))
 779                        continue;
 780
 781                /* A match is "weak" if it is with refs outside
 782                 * heads or tags, and did not specify the pattern
 783                 * in full (e.g. "refs/remotes/origin/master") or at
 784                 * least from the toplevel (e.g. "remotes/origin/master");
 785                 * otherwise "git push $URL master" would result in
 786                 * ambiguity between remotes/origin/master and heads/master
 787                 * at the remote site.
 788                 */
 789                if (namelen != patlen &&
 790                    patlen != namelen - 5 &&
 791                    prefixcmp(name, "refs/heads/") &&
 792                    prefixcmp(name, "refs/tags/")) {
 793                        /* We want to catch the case where only weak
 794                         * matches are found and there are multiple
 795                         * matches, and where more than one strong
 796                         * matches are found, as ambiguous.  One
 797                         * strong match with zero or more weak matches
 798                         * are acceptable as a unique match.
 799                         */
 800                        matched_weak = refs;
 801                        weak_match++;
 802                }
 803                else {
 804                        matched = refs;
 805                        match++;
 806                }
 807        }
 808        if (!matched) {
 809                *matched_ref = matched_weak;
 810                return weak_match;
 811        }
 812        else {
 813                *matched_ref = matched;
 814                return match;
 815        }
 816}
 817
 818static void tail_link_ref(struct ref *ref, struct ref ***tail)
 819{
 820        **tail = ref;
 821        while (ref->next)
 822                ref = ref->next;
 823        *tail = &ref->next;
 824}
 825
 826static struct ref *try_explicit_object_name(const char *name)
 827{
 828        unsigned char sha1[20];
 829        struct ref *ref;
 830
 831        if (!*name) {
 832                ref = alloc_ref(20);
 833                strcpy(ref->name, "(delete)");
 834                hashclr(ref->new_sha1);
 835                return ref;
 836        }
 837        if (get_sha1(name, sha1))
 838                return NULL;
 839        ref = alloc_ref_from_str(name);
 840        hashcpy(ref->new_sha1, sha1);
 841        return ref;
 842}
 843
 844static struct ref *make_linked_ref(const char *name, struct ref ***tail)
 845{
 846        struct ref *ret = alloc_ref_from_str(name);
 847        tail_link_ref(ret, tail);
 848        return ret;
 849}
 850
 851static char *guess_ref(const char *name, struct ref *peer)
 852{
 853        struct strbuf buf = STRBUF_INIT;
 854        unsigned char sha1[20];
 855
 856        const char *r = resolve_ref(peer->name, sha1, 1, NULL);
 857        if (!r)
 858                return NULL;
 859
 860        if (!prefixcmp(r, "refs/heads/"))
 861                strbuf_addstr(&buf, "refs/heads/");
 862        else if (!prefixcmp(r, "refs/tags/"))
 863                strbuf_addstr(&buf, "refs/tags/");
 864        else
 865                return NULL;
 866
 867        strbuf_addstr(&buf, name);
 868        return strbuf_detach(&buf, NULL);
 869}
 870
 871static int match_explicit(struct ref *src, struct ref *dst,
 872                          struct ref ***dst_tail,
 873                          struct refspec *rs)
 874{
 875        struct ref *matched_src, *matched_dst;
 876
 877        const char *dst_value = rs->dst;
 878        char *dst_guess;
 879
 880        if (rs->pattern || rs->matching)
 881                return 0;
 882
 883        matched_src = matched_dst = NULL;
 884        switch (count_refspec_match(rs->src, src, &matched_src)) {
 885        case 1:
 886                break;
 887        case 0:
 888                /* The source could be in the get_sha1() format
 889                 * not a reference name.  :refs/other is a
 890                 * way to delete 'other' ref at the remote end.
 891                 */
 892                matched_src = try_explicit_object_name(rs->src);
 893                if (!matched_src)
 894                        return error("src refspec %s does not match any.", rs->src);
 895                break;
 896        default:
 897                return error("src refspec %s matches more than one.", rs->src);
 898        }
 899
 900        if (!dst_value) {
 901                unsigned char sha1[20];
 902                int flag;
 903
 904                dst_value = resolve_ref(matched_src->name, sha1, 1, &flag);
 905                if (!dst_value ||
 906                    ((flag & REF_ISSYMREF) &&
 907                     prefixcmp(dst_value, "refs/heads/")))
 908                        die("%s cannot be resolved to branch.",
 909                            matched_src->name);
 910        }
 911
 912        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
 913        case 1:
 914                break;
 915        case 0:
 916                if (!memcmp(dst_value, "refs/", 5))
 917                        matched_dst = make_linked_ref(dst_value, dst_tail);
 918                else if((dst_guess = guess_ref(dst_value, matched_src)))
 919                        matched_dst = make_linked_ref(dst_guess, dst_tail);
 920                else
 921                        error("unable to push to unqualified destination: %s\n"
 922                              "The destination refspec neither matches an "
 923                              "existing ref on the remote nor\n"
 924                              "begins with refs/, and we are unable to "
 925                              "guess a prefix based on the source ref.",
 926                              dst_value);
 927                break;
 928        default:
 929                matched_dst = NULL;
 930                error("dst refspec %s matches more than one.",
 931                      dst_value);
 932                break;
 933        }
 934        if (!matched_dst)
 935                return -1;
 936        if (matched_dst->peer_ref)
 937                return error("dst ref %s receives from more than one src.",
 938                      matched_dst->name);
 939        else {
 940                matched_dst->peer_ref = matched_src;
 941                matched_dst->force = rs->force;
 942        }
 943        return 0;
 944}
 945
 946static int match_explicit_refs(struct ref *src, struct ref *dst,
 947                               struct ref ***dst_tail, struct refspec *rs,
 948                               int rs_nr)
 949{
 950        int i, errs;
 951        for (i = errs = 0; i < rs_nr; i++)
 952                errs += match_explicit(src, dst, dst_tail, &rs[i]);
 953        return errs;
 954}
 955
 956static const struct refspec *check_pattern_match(const struct refspec *rs,
 957                                                 int rs_nr,
 958                                                 const struct ref *src)
 959{
 960        int i;
 961        int matching_refs = -1;
 962        for (i = 0; i < rs_nr; i++) {
 963                if (rs[i].matching &&
 964                    (matching_refs == -1 || rs[i].force)) {
 965                        matching_refs = i;
 966                        continue;
 967                }
 968
 969                if (rs[i].pattern &&
 970                    !prefixcmp(src->name, rs[i].src) &&
 971                    src->name[strlen(rs[i].src)] == '/')
 972                        return rs + i;
 973        }
 974        if (matching_refs != -1)
 975                return rs + matching_refs;
 976        else
 977                return NULL;
 978}
 979
 980/*
 981 * Note. This is used only by "push"; refspec matching rules for
 982 * push and fetch are subtly different, so do not try to reuse it
 983 * without thinking.
 984 */
 985int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 986               int nr_refspec, const char **refspec, int flags)
 987{
 988        struct refspec *rs;
 989        int send_all = flags & MATCH_REFS_ALL;
 990        int send_mirror = flags & MATCH_REFS_MIRROR;
 991        static const char *default_refspec[] = { ":", 0 };
 992
 993        if (!nr_refspec) {
 994                nr_refspec = 1;
 995                refspec = default_refspec;
 996        }
 997        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
 998        if (match_explicit_refs(src, dst, dst_tail, rs, nr_refspec))
 999                return -1;
1000
1001        /* pick the remainder */
1002        for ( ; src; src = src->next) {
1003                struct ref *dst_peer;
1004                const struct refspec *pat = NULL;
1005                char *dst_name;
1006                if (src->peer_ref)
1007                        continue;
1008
1009                pat = check_pattern_match(rs, nr_refspec, src);
1010                if (!pat)
1011                        continue;
1012
1013                if (pat->matching) {
1014                        /*
1015                         * "matching refs"; traditionally we pushed everything
1016                         * including refs outside refs/heads/ hierarchy, but
1017                         * that does not make much sense these days.
1018                         */
1019                        if (!send_mirror && prefixcmp(src->name, "refs/heads/"))
1020                                continue;
1021                        dst_name = xstrdup(src->name);
1022
1023                } else {
1024                        const char *dst_side = pat->dst ? pat->dst : pat->src;
1025                        dst_name = xmalloc(strlen(dst_side) +
1026                                           strlen(src->name) -
1027                                           strlen(pat->src) + 2);
1028                        strcpy(dst_name, dst_side);
1029                        strcat(dst_name, src->name + strlen(pat->src));
1030                }
1031                dst_peer = find_ref_by_name(dst, dst_name);
1032                if (dst_peer) {
1033                        if (dst_peer->peer_ref)
1034                                /* We're already sending something to this ref. */
1035                                goto free_name;
1036
1037                } else {
1038                        if (pat->matching && !(send_all || send_mirror))
1039                                /*
1040                                 * Remote doesn't have it, and we have no
1041                                 * explicit pattern, and we don't have
1042                                 * --all nor --mirror.
1043                                 */
1044                                goto free_name;
1045
1046                        /* Create a new one and link it */
1047                        dst_peer = make_linked_ref(dst_name, dst_tail);
1048                        hashcpy(dst_peer->new_sha1, src->new_sha1);
1049                }
1050                dst_peer->peer_ref = src;
1051                dst_peer->force = pat->force;
1052        free_name:
1053                free(dst_name);
1054        }
1055        return 0;
1056}
1057
1058struct branch *branch_get(const char *name)
1059{
1060        struct branch *ret;
1061
1062        read_config();
1063        if (!name || !*name || !strcmp(name, "HEAD"))
1064                ret = current_branch;
1065        else
1066                ret = make_branch(name, 0);
1067        if (ret && ret->remote_name) {
1068                ret->remote = remote_get(ret->remote_name);
1069                if (ret->merge_nr) {
1070                        int i;
1071                        ret->merge = xcalloc(sizeof(*ret->merge),
1072                                             ret->merge_nr);
1073                        for (i = 0; i < ret->merge_nr; i++) {
1074                                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1075                                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1076                                remote_find_tracking(ret->remote,
1077                                                     ret->merge[i]);
1078                        }
1079                }
1080        }
1081        return ret;
1082}
1083
1084int branch_has_merge_config(struct branch *branch)
1085{
1086        return branch && !!branch->merge;
1087}
1088
1089int branch_merge_matches(struct branch *branch,
1090                                 int i,
1091                                 const char *refname)
1092{
1093        if (!branch || i < 0 || i >= branch->merge_nr)
1094                return 0;
1095        return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
1096}
1097
1098static struct ref *get_expanded_map(const struct ref *remote_refs,
1099                                    const struct refspec *refspec)
1100{
1101        const struct ref *ref;
1102        struct ref *ret = NULL;
1103        struct ref **tail = &ret;
1104
1105        int remote_prefix_len = strlen(refspec->src);
1106        int local_prefix_len = strlen(refspec->dst);
1107
1108        for (ref = remote_refs; ref; ref = ref->next) {
1109                if (strchr(ref->name, '^'))
1110                        continue; /* a dereference item */
1111                if (!prefixcmp(ref->name, refspec->src)) {
1112                        const char *match;
1113                        struct ref *cpy = copy_ref(ref);
1114                        match = ref->name + remote_prefix_len;
1115
1116                        cpy->peer_ref = alloc_ref(local_prefix_len +
1117                                                  strlen(match) + 1);
1118                        sprintf(cpy->peer_ref->name, "%s%s",
1119                                refspec->dst, match);
1120                        if (refspec->force)
1121                                cpy->peer_ref->force = 1;
1122                        *tail = cpy;
1123                        tail = &cpy->next;
1124                }
1125        }
1126
1127        return ret;
1128}
1129
1130static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1131{
1132        const struct ref *ref;
1133        for (ref = refs; ref; ref = ref->next) {
1134                if (refname_match(name, ref->name, ref_fetch_rules))
1135                        return ref;
1136        }
1137        return NULL;
1138}
1139
1140struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1141{
1142        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1143
1144        if (!ref)
1145                return NULL;
1146
1147        return copy_ref(ref);
1148}
1149
1150static struct ref *get_local_ref(const char *name)
1151{
1152        struct ref *ret;
1153        if (!name)
1154                return NULL;
1155
1156        if (!prefixcmp(name, "refs/")) {
1157                return alloc_ref_from_str(name);
1158        }
1159
1160        if (!prefixcmp(name, "heads/") ||
1161            !prefixcmp(name, "tags/") ||
1162            !prefixcmp(name, "remotes/")) {
1163                ret = alloc_ref(strlen(name) + 6);
1164                sprintf(ret->name, "refs/%s", name);
1165                return ret;
1166        }
1167
1168        ret = alloc_ref(strlen(name) + 12);
1169        sprintf(ret->name, "refs/heads/%s", name);
1170        return ret;
1171}
1172
1173int get_fetch_map(const struct ref *remote_refs,
1174                  const struct refspec *refspec,
1175                  struct ref ***tail,
1176                  int missing_ok)
1177{
1178        struct ref *ref_map, **rmp;
1179
1180        if (refspec->pattern) {
1181                ref_map = get_expanded_map(remote_refs, refspec);
1182        } else {
1183                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1184
1185                ref_map = get_remote_ref(remote_refs, name);
1186                if (!missing_ok && !ref_map)
1187                        die("Couldn't find remote ref %s", name);
1188                if (ref_map) {
1189                        ref_map->peer_ref = get_local_ref(refspec->dst);
1190                        if (ref_map->peer_ref && refspec->force)
1191                                ref_map->peer_ref->force = 1;
1192                }
1193        }
1194
1195        for (rmp = &ref_map; *rmp; ) {
1196                if ((*rmp)->peer_ref) {
1197                        int st = check_ref_format((*rmp)->peer_ref->name + 5);
1198                        if (st && st != CHECK_REF_FORMAT_ONELEVEL) {
1199                                struct ref *ignore = *rmp;
1200                                error("* Ignoring funny ref '%s' locally",
1201                                      (*rmp)->peer_ref->name);
1202                                *rmp = (*rmp)->next;
1203                                free(ignore->peer_ref);
1204                                free(ignore);
1205                                continue;
1206                        }
1207                }
1208                rmp = &((*rmp)->next);
1209        }
1210
1211        if (ref_map)
1212                tail_link_ref(ref_map, tail);
1213
1214        return 0;
1215}
1216
1217int resolve_remote_symref(struct ref *ref, struct ref *list)
1218{
1219        if (!ref->symref)
1220                return 0;
1221        for (; list; list = list->next)
1222                if (!strcmp(ref->symref, list->name)) {
1223                        hashcpy(ref->old_sha1, list->old_sha1);
1224                        return 0;
1225                }
1226        return 1;
1227}
1228
1229/*
1230 * Return true if there is anything to report, otherwise false.
1231 */
1232int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
1233{
1234        unsigned char sha1[20];
1235        struct commit *ours, *theirs;
1236        char symmetric[84];
1237        struct rev_info revs;
1238        const char *rev_argv[10], *base;
1239        int rev_argc;
1240
1241        /*
1242         * Nothing to report unless we are marked to build on top of
1243         * somebody else.
1244         */
1245        if (!branch ||
1246            !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
1247                return 0;
1248
1249        /*
1250         * If what we used to build on no longer exists, there is
1251         * nothing to report.
1252         */
1253        base = branch->merge[0]->dst;
1254        if (!resolve_ref(base, sha1, 1, NULL))
1255                return 0;
1256        theirs = lookup_commit(sha1);
1257        if (!theirs)
1258                return 0;
1259
1260        if (!resolve_ref(branch->refname, sha1, 1, NULL))
1261                return 0;
1262        ours = lookup_commit(sha1);
1263        if (!ours)
1264                return 0;
1265
1266        /* are we the same? */
1267        if (theirs == ours)
1268                return 0;
1269
1270        /* Run "rev-list --left-right ours...theirs" internally... */
1271        rev_argc = 0;
1272        rev_argv[rev_argc++] = NULL;
1273        rev_argv[rev_argc++] = "--left-right";
1274        rev_argv[rev_argc++] = symmetric;
1275        rev_argv[rev_argc++] = "--";
1276        rev_argv[rev_argc] = NULL;
1277
1278        strcpy(symmetric, sha1_to_hex(ours->object.sha1));
1279        strcpy(symmetric + 40, "...");
1280        strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
1281
1282        init_revisions(&revs, NULL);
1283        setup_revisions(rev_argc, rev_argv, &revs, NULL);
1284        prepare_revision_walk(&revs);
1285
1286        /* ... and count the commits on each side. */
1287        *num_ours = 0;
1288        *num_theirs = 0;
1289        while (1) {
1290                struct commit *c = get_revision(&revs);
1291                if (!c)
1292                        break;
1293                if (c->object.flags & SYMMETRIC_LEFT)
1294                        (*num_ours)++;
1295                else
1296                        (*num_theirs)++;
1297        }
1298
1299        /* clear object flags smudged by the above traversal */
1300        clear_commit_marks(ours, ALL_REV_FLAGS);
1301        clear_commit_marks(theirs, ALL_REV_FLAGS);
1302        return 1;
1303}
1304
1305/*
1306 * Return true when there is anything to report, otherwise false.
1307 */
1308int format_tracking_info(struct branch *branch, struct strbuf *sb)
1309{
1310        int num_ours, num_theirs;
1311        const char *base;
1312
1313        if (!stat_tracking_info(branch, &num_ours, &num_theirs))
1314                return 0;
1315
1316        base = branch->merge[0]->dst;
1317        if (!prefixcmp(base, "refs/remotes/")) {
1318                base += strlen("refs/remotes/");
1319        }
1320        if (!num_theirs)
1321                strbuf_addf(sb, "Your branch is ahead of '%s' "
1322                            "by %d commit%s.\n",
1323                            base, num_ours, (num_ours == 1) ? "" : "s");
1324        else if (!num_ours)
1325                strbuf_addf(sb, "Your branch is behind '%s' "
1326                            "by %d commit%s, "
1327                            "and can be fast-forwarded.\n",
1328                            base, num_theirs, (num_theirs == 1) ? "" : "s");
1329        else
1330                strbuf_addf(sb, "Your branch and '%s' have diverged,\n"
1331                            "and have %d and %d different commit(s) each, "
1332                            "respectively.\n",
1333                            base, num_ours, num_theirs);
1334        return 1;
1335}