Andrew's git / gitweb.git / remote.c
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remote.con commit Change xdl_merge to generate output even for null merges (5719db9)
   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        /*
 302         * Cogito compatible push: push current HEAD to remote #branch
 303         * (master if missing)
 304         */
 305        strbuf_init(&branch, 0);
 306        strbuf_addstr(&branch, "HEAD");
 307        if (frag)
 308                strbuf_addf(&branch, ":refs/heads/%s", frag);
 309        else
 310                strbuf_addstr(&branch, ":refs/heads/master");
 311        add_push_refspec(remote, strbuf_detach(&branch, 0));
 312        remote->fetch_tags = 1; /* always auto-follow */
 313}
 314
 315static int handle_config(const char *key, const char *value, void *cb)
 316{
 317        const char *name;
 318        const char *subkey;
 319        struct remote *remote;
 320        struct branch *branch;
 321        if (!prefixcmp(key, "branch.")) {
 322                name = key + 7;
 323                subkey = strrchr(name, '.');
 324                if (!subkey)
 325                        return 0;
 326                branch = make_branch(name, subkey - name);
 327                if (!strcmp(subkey, ".remote")) {
 328                        if (!value)
 329                                return config_error_nonbool(key);
 330                        branch->remote_name = xstrdup(value);
 331                        if (branch == current_branch)
 332                                default_remote_name = branch->remote_name;
 333                } else if (!strcmp(subkey, ".merge")) {
 334                        if (!value)
 335                                return config_error_nonbool(key);
 336                        add_merge(branch, xstrdup(value));
 337                }
 338                return 0;
 339        }
 340        if (!prefixcmp(key, "url.")) {
 341                struct rewrite *rewrite;
 342                name = key + 4;
 343                subkey = strrchr(name, '.');
 344                if (!subkey)
 345                        return 0;
 346                rewrite = make_rewrite(name, subkey - name);
 347                if (!strcmp(subkey, ".insteadof")) {
 348                        if (!value)
 349                                return config_error_nonbool(key);
 350                        add_instead_of(rewrite, xstrdup(value));
 351                }
 352        }
 353        if (prefixcmp(key,  "remote."))
 354                return 0;
 355        name = key + 7;
 356        if (*name == '/') {
 357                warning("Config remote shorthand cannot begin with '/': %s",
 358                        name);
 359                return 0;
 360        }
 361        subkey = strrchr(name, '.');
 362        if (!subkey)
 363                return error("Config with no key for remote %s", name);
 364        remote = make_remote(name, subkey - name);
 365        if (!strcmp(subkey, ".mirror"))
 366                remote->mirror = git_config_bool(key, value);
 367        else if (!strcmp(subkey, ".skipdefaultupdate"))
 368                remote->skip_default_update = git_config_bool(key, value);
 369
 370        else if (!strcmp(subkey, ".url")) {
 371                const char *v;
 372                if (git_config_string(&v, key, value))
 373                        return -1;
 374                add_url(remote, v);
 375        } else if (!strcmp(subkey, ".push")) {
 376                const char *v;
 377                if (git_config_string(&v, key, value))
 378                        return -1;
 379                add_push_refspec(remote, v);
 380        } else if (!strcmp(subkey, ".fetch")) {
 381                const char *v;
 382                if (git_config_string(&v, key, value))
 383                        return -1;
 384                add_fetch_refspec(remote, v);
 385        } else if (!strcmp(subkey, ".receivepack")) {
 386                const char *v;
 387                if (git_config_string(&v, key, value))
 388                        return -1;
 389                if (!remote->receivepack)
 390                        remote->receivepack = v;
 391                else
 392                        error("more than one receivepack given, using the first");
 393        } else if (!strcmp(subkey, ".uploadpack")) {
 394                const char *v;
 395                if (git_config_string(&v, key, value))
 396                        return -1;
 397                if (!remote->uploadpack)
 398                        remote->uploadpack = v;
 399                else
 400                        error("more than one uploadpack given, using the first");
 401        } else if (!strcmp(subkey, ".tagopt")) {
 402                if (!strcmp(value, "--no-tags"))
 403                        remote->fetch_tags = -1;
 404        } else if (!strcmp(subkey, ".proxy")) {
 405                return git_config_string((const char **)&remote->http_proxy,
 406                                         key, value);
 407        }
 408        return 0;
 409}
 410
 411static void alias_all_urls(void)
 412{
 413        int i, j;
 414        for (i = 0; i < remotes_nr; i++) {
 415                if (!remotes[i])
 416                        continue;
 417                for (j = 0; j < remotes[i]->url_nr; j++) {
 418                        remotes[i]->url[j] = alias_url(remotes[i]->url[j]);
 419                }
 420        }
 421}
 422
 423static void read_config(void)
 424{
 425        unsigned char sha1[20];
 426        const char *head_ref;
 427        int flag;
 428        if (default_remote_name) // did this already
 429                return;
 430        default_remote_name = xstrdup("origin");
 431        current_branch = NULL;
 432        head_ref = resolve_ref("HEAD", sha1, 0, &flag);
 433        if (head_ref && (flag & REF_ISSYMREF) &&
 434            !prefixcmp(head_ref, "refs/heads/")) {
 435                current_branch =
 436                        make_branch(head_ref + strlen("refs/heads/"), 0);
 437        }
 438        git_config(handle_config, NULL);
 439        alias_all_urls();
 440}
 441
 442/*
 443 * We need to make sure the tracking branches are well formed, but a
 444 * wildcard refspec in "struct refspec" must have a trailing slash. We
 445 * temporarily drop the trailing '/' while calling check_ref_format(),
 446 * and put it back.  The caller knows that a CHECK_REF_FORMAT_ONELEVEL
 447 * error return is Ok for a wildcard refspec.
 448 */
 449static int verify_refname(char *name, int is_glob)
 450{
 451        int result, len = -1;
 452
 453        if (is_glob) {
 454                len = strlen(name);
 455                assert(name[len - 1] == '/');
 456                name[len - 1] = '\0';
 457        }
 458        result = check_ref_format(name);
 459        if (is_glob)
 460                name[len - 1] = '/';
 461        return result;
 462}
 463
 464static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 465{
 466        int i;
 467        int st;
 468        struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 469
 470        for (i = 0; i < nr_refspec; i++) {
 471                size_t llen;
 472                int is_glob;
 473                const char *lhs, *rhs;
 474
 475                llen = is_glob = 0;
 476
 477                lhs = refspec[i];
 478                if (*lhs == '+') {
 479                        rs[i].force = 1;
 480                        lhs++;
 481                }
 482
 483                rhs = strrchr(lhs, ':');
 484
 485                /*
 486                 * Before going on, special case ":" (or "+:") as a refspec
 487                 * for matching refs.
 488                 */
 489                if (!fetch && rhs == lhs && rhs[1] == '\0') {
 490                        rs[i].matching = 1;
 491                        continue;
 492                }
 493
 494                if (rhs) {
 495                        size_t rlen = strlen(++rhs);
 496                        is_glob = (2 <= rlen && !strcmp(rhs + rlen - 2, "/*"));
 497                        rs[i].dst = xstrndup(rhs, rlen - is_glob);
 498                }
 499
 500                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 501                if (2 <= llen && !memcmp(lhs + llen - 2, "/*", 2)) {
 502                        if ((rhs && !is_glob) || (!rhs && fetch))
 503                                goto invalid;
 504                        is_glob = 1;
 505                        llen--;
 506                } else if (rhs && is_glob) {
 507                        goto invalid;
 508                }
 509
 510                rs[i].pattern = is_glob;
 511                rs[i].src = xstrndup(lhs, llen);
 512
 513                if (fetch) {
 514                        /*
 515                         * LHS
 516                         * - empty is allowed; it means HEAD.
 517                         * - otherwise it must be a valid looking ref.
 518                         */
 519                        if (!*rs[i].src)
 520                                ; /* empty is ok */
 521                        else {
 522                                st = verify_refname(rs[i].src, is_glob);
 523                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 524                                        goto invalid;
 525                        }
 526                        /*
 527                         * RHS
 528                         * - missing is ok, and is same as empty.
 529                         * - empty is ok; it means not to store.
 530                         * - otherwise it must be a valid looking ref.
 531                         */
 532                        if (!rs[i].dst) {
 533                                ; /* ok */
 534                        } else if (!*rs[i].dst) {
 535                                ; /* ok */
 536                        } else {
 537                                st = verify_refname(rs[i].dst, is_glob);
 538                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 539                                        goto invalid;
 540                        }
 541                } else {
 542                        /*
 543                         * LHS
 544                         * - empty is allowed; it means delete.
 545                         * - when wildcarded, it must be a valid looking ref.
 546                         * - otherwise, it must be an extended SHA-1, but
 547                         *   there is no existing way to validate this.
 548                         */
 549                        if (!*rs[i].src)
 550                                ; /* empty is ok */
 551                        else if (is_glob) {
 552                                st = verify_refname(rs[i].src, is_glob);
 553                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 554                                        goto invalid;
 555                        }
 556                        else
 557                                ; /* anything goes, for now */
 558                        /*
 559                         * RHS
 560                         * - missing is allowed, but LHS then must be a
 561                         *   valid looking ref.
 562                         * - empty is not allowed.
 563                         * - otherwise it must be a valid looking ref.
 564                         */
 565                        if (!rs[i].dst) {
 566                                st = verify_refname(rs[i].src, is_glob);
 567                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 568                                        goto invalid;
 569                        } else if (!*rs[i].dst) {
 570                                goto invalid;
 571                        } else {
 572                                st = verify_refname(rs[i].dst, is_glob);
 573                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 574                                        goto invalid;
 575                        }
 576                }
 577        }
 578        return rs;
 579
 580 invalid:
 581        if (verify) {
 582                free(rs);
 583                return NULL;
 584        }
 585        die("Invalid refspec '%s'", refspec[i]);
 586}
 587
 588int valid_fetch_refspec(const char *fetch_refspec_str)
 589{
 590        const char *fetch_refspec[] = { fetch_refspec_str };
 591        struct refspec *refspec;
 592
 593        refspec = parse_refspec_internal(1, fetch_refspec, 1, 1);
 594        free(refspec);
 595        return !!refspec;
 596}
 597
 598struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 599{
 600        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 601}
 602
 603struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 604{
 605        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 606}
 607
 608static int valid_remote_nick(const char *name)
 609{
 610        if (!name[0] || /* not empty */
 611            (name[0] == '.' && /* not "." */
 612             (!name[1] || /* not ".." */
 613              (name[1] == '.' && !name[2]))))
 614                return 0;
 615        return !strchr(name, '/'); /* no slash */
 616}
 617
 618struct remote *remote_get(const char *name)
 619{
 620        struct remote *ret;
 621
 622        read_config();
 623        if (!name)
 624                name = default_remote_name;
 625        ret = make_remote(name, 0);
 626        if (valid_remote_nick(name)) {
 627                if (!ret->url)
 628                        read_remotes_file(ret);
 629                if (!ret->url)
 630                        read_branches_file(ret);
 631        }
 632        if (!ret->url)
 633                add_url_alias(ret, name);
 634        if (!ret->url)
 635                return NULL;
 636        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 637        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 638        return ret;
 639}
 640
 641int for_each_remote(each_remote_fn fn, void *priv)
 642{
 643        int i, result = 0;
 644        read_config();
 645        for (i = 0; i < remotes_nr && !result; i++) {
 646                struct remote *r = remotes[i];
 647                if (!r)
 648                        continue;
 649                if (!r->fetch)
 650                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 651                                                       r->fetch_refspec);
 652                if (!r->push)
 653                        r->push = parse_push_refspec(r->push_refspec_nr,
 654                                                     r->push_refspec);
 655                result = fn(r, priv);
 656        }
 657        return result;
 658}
 659
 660void ref_remove_duplicates(struct ref *ref_map)
 661{
 662        struct ref **posn;
 663        struct ref *next;
 664        for (; ref_map; ref_map = ref_map->next) {
 665                if (!ref_map->peer_ref)
 666                        continue;
 667                posn = &ref_map->next;
 668                while (*posn) {
 669                        if ((*posn)->peer_ref &&
 670                            !strcmp((*posn)->peer_ref->name,
 671                                    ref_map->peer_ref->name)) {
 672                                if (strcmp((*posn)->name, ref_map->name))
 673                                        die("%s tracks both %s and %s",
 674                                            ref_map->peer_ref->name,
 675                                            (*posn)->name, ref_map->name);
 676                                next = (*posn)->next;
 677                                free((*posn)->peer_ref);
 678                                free(*posn);
 679                                *posn = next;
 680                        } else {
 681                                posn = &(*posn)->next;
 682                        }
 683                }
 684        }
 685}
 686
 687int remote_has_url(struct remote *remote, const char *url)
 688{
 689        int i;
 690        for (i = 0; i < remote->url_nr; i++) {
 691                if (!strcmp(remote->url[i], url))
 692                        return 1;
 693        }
 694        return 0;
 695}
 696
 697int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 698{
 699        int find_src = refspec->src == NULL;
 700        char *needle, **result;
 701        int i;
 702
 703        if (find_src) {
 704                if (!refspec->dst)
 705                        return error("find_tracking: need either src or dst");
 706                needle = refspec->dst;
 707                result = &refspec->src;
 708        } else {
 709                needle = refspec->src;
 710                result = &refspec->dst;
 711        }
 712
 713        for (i = 0; i < remote->fetch_refspec_nr; i++) {
 714                struct refspec *fetch = &remote->fetch[i];
 715                const char *key = find_src ? fetch->dst : fetch->src;
 716                const char *value = find_src ? fetch->src : fetch->dst;
 717                if (!fetch->dst)
 718                        continue;
 719                if (fetch->pattern) {
 720                        if (!prefixcmp(needle, key)) {
 721                                *result = xmalloc(strlen(value) +
 722                                                  strlen(needle) -
 723                                                  strlen(key) + 1);
 724                                strcpy(*result, value);
 725                                strcpy(*result + strlen(value),
 726                                       needle + strlen(key));
 727                                refspec->force = fetch->force;
 728                                return 0;
 729                        }
 730                } else if (!strcmp(needle, key)) {
 731                        *result = xstrdup(value);
 732                        refspec->force = fetch->force;
 733                        return 0;
 734                }
 735        }
 736        return -1;
 737}
 738
 739struct ref *alloc_ref(unsigned namelen)
 740{
 741        struct ref *ret = xmalloc(sizeof(struct ref) + namelen);
 742        memset(ret, 0, sizeof(struct ref) + namelen);
 743        return ret;
 744}
 745
 746struct ref *alloc_ref_from_str(const char* str)
 747{
 748        struct ref *ret = alloc_ref(strlen(str) + 1);
 749        strcpy(ret->name, str);
 750        return ret;
 751}
 752
 753static struct ref *copy_ref(const struct ref *ref)
 754{
 755        struct ref *ret = xmalloc(sizeof(struct ref) + strlen(ref->name) + 1);
 756        memcpy(ret, ref, sizeof(struct ref) + strlen(ref->name) + 1);
 757        ret->next = NULL;
 758        return ret;
 759}
 760
 761struct ref *copy_ref_list(const struct ref *ref)
 762{
 763        struct ref *ret = NULL;
 764        struct ref **tail = &ret;
 765        while (ref) {
 766                *tail = copy_ref(ref);
 767                ref = ref->next;
 768                tail = &((*tail)->next);
 769        }
 770        return ret;
 771}
 772
 773void free_ref(struct ref *ref)
 774{
 775        if (!ref)
 776                return;
 777        free(ref->remote_status);
 778        free(ref->symref);
 779        free(ref);
 780}
 781
 782void free_refs(struct ref *ref)
 783{
 784        struct ref *next;
 785        while (ref) {
 786                next = ref->next;
 787                free(ref->peer_ref);
 788                free_ref(ref);
 789                ref = next;
 790        }
 791}
 792
 793static int count_refspec_match(const char *pattern,
 794                               struct ref *refs,
 795                               struct ref **matched_ref)
 796{
 797        int patlen = strlen(pattern);
 798        struct ref *matched_weak = NULL;
 799        struct ref *matched = NULL;
 800        int weak_match = 0;
 801        int match = 0;
 802
 803        for (weak_match = match = 0; refs; refs = refs->next) {
 804                char *name = refs->name;
 805                int namelen = strlen(name);
 806
 807                if (!refname_match(pattern, name, ref_rev_parse_rules))
 808                        continue;
 809
 810                /* A match is "weak" if it is with refs outside
 811                 * heads or tags, and did not specify the pattern
 812                 * in full (e.g. "refs/remotes/origin/master") or at
 813                 * least from the toplevel (e.g. "remotes/origin/master");
 814                 * otherwise "git push $URL master" would result in
 815                 * ambiguity between remotes/origin/master and heads/master
 816                 * at the remote site.
 817                 */
 818                if (namelen != patlen &&
 819                    patlen != namelen - 5 &&
 820                    prefixcmp(name, "refs/heads/") &&
 821                    prefixcmp(name, "refs/tags/")) {
 822                        /* We want to catch the case where only weak
 823                         * matches are found and there are multiple
 824                         * matches, and where more than one strong
 825                         * matches are found, as ambiguous.  One
 826                         * strong match with zero or more weak matches
 827                         * are acceptable as a unique match.
 828                         */
 829                        matched_weak = refs;
 830                        weak_match++;
 831                }
 832                else {
 833                        matched = refs;
 834                        match++;
 835                }
 836        }
 837        if (!matched) {
 838                *matched_ref = matched_weak;
 839                return weak_match;
 840        }
 841        else {
 842                *matched_ref = matched;
 843                return match;
 844        }
 845}
 846
 847static void tail_link_ref(struct ref *ref, struct ref ***tail)
 848{
 849        **tail = ref;
 850        while (ref->next)
 851                ref = ref->next;
 852        *tail = &ref->next;
 853}
 854
 855static struct ref *try_explicit_object_name(const char *name)
 856{
 857        unsigned char sha1[20];
 858        struct ref *ref;
 859
 860        if (!*name) {
 861                ref = alloc_ref(20);
 862                strcpy(ref->name, "(delete)");
 863                hashclr(ref->new_sha1);
 864                return ref;
 865        }
 866        if (get_sha1(name, sha1))
 867                return NULL;
 868        ref = alloc_ref_from_str(name);
 869        hashcpy(ref->new_sha1, sha1);
 870        return ref;
 871}
 872
 873static struct ref *make_linked_ref(const char *name, struct ref ***tail)
 874{
 875        struct ref *ret = alloc_ref_from_str(name);
 876        tail_link_ref(ret, tail);
 877        return ret;
 878}
 879
 880static char *guess_ref(const char *name, struct ref *peer)
 881{
 882        struct strbuf buf = STRBUF_INIT;
 883        unsigned char sha1[20];
 884
 885        const char *r = resolve_ref(peer->name, sha1, 1, NULL);
 886        if (!r)
 887                return NULL;
 888
 889        if (!prefixcmp(r, "refs/heads/"))
 890                strbuf_addstr(&buf, "refs/heads/");
 891        else if (!prefixcmp(r, "refs/tags/"))
 892                strbuf_addstr(&buf, "refs/tags/");
 893        else
 894                return NULL;
 895
 896        strbuf_addstr(&buf, name);
 897        return strbuf_detach(&buf, NULL);
 898}
 899
 900static int match_explicit(struct ref *src, struct ref *dst,
 901                          struct ref ***dst_tail,
 902                          struct refspec *rs)
 903{
 904        struct ref *matched_src, *matched_dst;
 905
 906        const char *dst_value = rs->dst;
 907        char *dst_guess;
 908
 909        if (rs->pattern || rs->matching)
 910                return 0;
 911
 912        matched_src = matched_dst = NULL;
 913        switch (count_refspec_match(rs->src, src, &matched_src)) {
 914        case 1:
 915                break;
 916        case 0:
 917                /* The source could be in the get_sha1() format
 918                 * not a reference name.  :refs/other is a
 919                 * way to delete 'other' ref at the remote end.
 920                 */
 921                matched_src = try_explicit_object_name(rs->src);
 922                if (!matched_src)
 923                        return error("src refspec %s does not match any.", rs->src);
 924                break;
 925        default:
 926                return error("src refspec %s matches more than one.", rs->src);
 927        }
 928
 929        if (!dst_value) {
 930                unsigned char sha1[20];
 931                int flag;
 932
 933                dst_value = resolve_ref(matched_src->name, sha1, 1, &flag);
 934                if (!dst_value ||
 935                    ((flag & REF_ISSYMREF) &&
 936                     prefixcmp(dst_value, "refs/heads/")))
 937                        die("%s cannot be resolved to branch.",
 938                            matched_src->name);
 939        }
 940
 941        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
 942        case 1:
 943                break;
 944        case 0:
 945                if (!memcmp(dst_value, "refs/", 5))
 946                        matched_dst = make_linked_ref(dst_value, dst_tail);
 947                else if((dst_guess = guess_ref(dst_value, matched_src)))
 948                        matched_dst = make_linked_ref(dst_guess, dst_tail);
 949                else
 950                        error("unable to push to unqualified destination: %s\n"
 951                              "The destination refspec neither matches an "
 952                              "existing ref on the remote nor\n"
 953                              "begins with refs/, and we are unable to "
 954                              "guess a prefix based on the source ref.",
 955                              dst_value);
 956                break;
 957        default:
 958                matched_dst = NULL;
 959                error("dst refspec %s matches more than one.",
 960                      dst_value);
 961                break;
 962        }
 963        if (!matched_dst)
 964                return -1;
 965        if (matched_dst->peer_ref)
 966                return error("dst ref %s receives from more than one src.",
 967                      matched_dst->name);
 968        else {
 969                matched_dst->peer_ref = matched_src;
 970                matched_dst->force = rs->force;
 971        }
 972        return 0;
 973}
 974
 975static int match_explicit_refs(struct ref *src, struct ref *dst,
 976                               struct ref ***dst_tail, struct refspec *rs,
 977                               int rs_nr)
 978{
 979        int i, errs;
 980        for (i = errs = 0; i < rs_nr; i++)
 981                errs += match_explicit(src, dst, dst_tail, &rs[i]);
 982        return errs;
 983}
 984
 985static const struct refspec *check_pattern_match(const struct refspec *rs,
 986                                                 int rs_nr,
 987                                                 const struct ref *src)
 988{
 989        int i;
 990        int matching_refs = -1;
 991        for (i = 0; i < rs_nr; i++) {
 992                if (rs[i].matching &&
 993                    (matching_refs == -1 || rs[i].force)) {
 994                        matching_refs = i;
 995                        continue;
 996                }
 997
 998                if (rs[i].pattern && !prefixcmp(src->name, rs[i].src))
 999                        return rs + i;
1000        }
1001        if (matching_refs != -1)
1002                return rs + matching_refs;
1003        else
1004                return NULL;
1005}
1006
1007/*
1008 * Note. This is used only by "push"; refspec matching rules for
1009 * push and fetch are subtly different, so do not try to reuse it
1010 * without thinking.
1011 */
1012int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
1013               int nr_refspec, const char **refspec, int flags)
1014{
1015        struct refspec *rs;
1016        int send_all = flags & MATCH_REFS_ALL;
1017        int send_mirror = flags & MATCH_REFS_MIRROR;
1018        static const char *default_refspec[] = { ":", 0 };
1019
1020        if (!nr_refspec) {
1021                nr_refspec = 1;
1022                refspec = default_refspec;
1023        }
1024        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1025        if (match_explicit_refs(src, dst, dst_tail, rs, nr_refspec))
1026                return -1;
1027
1028        /* pick the remainder */
1029        for ( ; src; src = src->next) {
1030                struct ref *dst_peer;
1031                const struct refspec *pat = NULL;
1032                char *dst_name;
1033                if (src->peer_ref)
1034                        continue;
1035
1036                pat = check_pattern_match(rs, nr_refspec, src);
1037                if (!pat)
1038                        continue;
1039
1040                if (pat->matching) {
1041                        /*
1042                         * "matching refs"; traditionally we pushed everything
1043                         * including refs outside refs/heads/ hierarchy, but
1044                         * that does not make much sense these days.
1045                         */
1046                        if (!send_mirror && prefixcmp(src->name, "refs/heads/"))
1047                                continue;
1048                        dst_name = xstrdup(src->name);
1049
1050                } else {
1051                        const char *dst_side = pat->dst ? pat->dst : pat->src;
1052                        dst_name = xmalloc(strlen(dst_side) +
1053                                           strlen(src->name) -
1054                                           strlen(pat->src) + 2);
1055                        strcpy(dst_name, dst_side);
1056                        strcat(dst_name, src->name + strlen(pat->src));
1057                }
1058                dst_peer = find_ref_by_name(dst, dst_name);
1059                if (dst_peer) {
1060                        if (dst_peer->peer_ref)
1061                                /* We're already sending something to this ref. */
1062                                goto free_name;
1063
1064                } else {
1065                        if (pat->matching && !(send_all || send_mirror))
1066                                /*
1067                                 * Remote doesn't have it, and we have no
1068                                 * explicit pattern, and we don't have
1069                                 * --all nor --mirror.
1070                                 */
1071                                goto free_name;
1072
1073                        /* Create a new one and link it */
1074                        dst_peer = make_linked_ref(dst_name, dst_tail);
1075                        hashcpy(dst_peer->new_sha1, src->new_sha1);
1076                }
1077                dst_peer->peer_ref = src;
1078                dst_peer->force = pat->force;
1079        free_name:
1080                free(dst_name);
1081        }
1082        return 0;
1083}
1084
1085struct branch *branch_get(const char *name)
1086{
1087        struct branch *ret;
1088
1089        read_config();
1090        if (!name || !*name || !strcmp(name, "HEAD"))
1091                ret = current_branch;
1092        else
1093                ret = make_branch(name, 0);
1094        if (ret && ret->remote_name) {
1095                ret->remote = remote_get(ret->remote_name);
1096                if (ret->merge_nr) {
1097                        int i;
1098                        ret->merge = xcalloc(sizeof(*ret->merge),
1099                                             ret->merge_nr);
1100                        for (i = 0; i < ret->merge_nr; i++) {
1101                                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1102                                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1103                                remote_find_tracking(ret->remote,
1104                                                     ret->merge[i]);
1105                        }
1106                }
1107        }
1108        return ret;
1109}
1110
1111int branch_has_merge_config(struct branch *branch)
1112{
1113        return branch && !!branch->merge;
1114}
1115
1116int branch_merge_matches(struct branch *branch,
1117                                 int i,
1118                                 const char *refname)
1119{
1120        if (!branch || i < 0 || i >= branch->merge_nr)
1121                return 0;
1122        return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
1123}
1124
1125static struct ref *get_expanded_map(const struct ref *remote_refs,
1126                                    const struct refspec *refspec)
1127{
1128        const struct ref *ref;
1129        struct ref *ret = NULL;
1130        struct ref **tail = &ret;
1131
1132        int remote_prefix_len = strlen(refspec->src);
1133        int local_prefix_len = strlen(refspec->dst);
1134
1135        for (ref = remote_refs; ref; ref = ref->next) {
1136                if (strchr(ref->name, '^'))
1137                        continue; /* a dereference item */
1138                if (!prefixcmp(ref->name, refspec->src)) {
1139                        const char *match;
1140                        struct ref *cpy = copy_ref(ref);
1141                        match = ref->name + remote_prefix_len;
1142
1143                        cpy->peer_ref = alloc_ref(local_prefix_len +
1144                                                  strlen(match) + 1);
1145                        sprintf(cpy->peer_ref->name, "%s%s",
1146                                refspec->dst, match);
1147                        if (refspec->force)
1148                                cpy->peer_ref->force = 1;
1149                        *tail = cpy;
1150                        tail = &cpy->next;
1151                }
1152        }
1153
1154        return ret;
1155}
1156
1157static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1158{
1159        const struct ref *ref;
1160        for (ref = refs; ref; ref = ref->next) {
1161                if (refname_match(name, ref->name, ref_fetch_rules))
1162                        return ref;
1163        }
1164        return NULL;
1165}
1166
1167struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1168{
1169        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1170
1171        if (!ref)
1172                return NULL;
1173
1174        return copy_ref(ref);
1175}
1176
1177static struct ref *get_local_ref(const char *name)
1178{
1179        struct ref *ret;
1180        if (!name)
1181                return NULL;
1182
1183        if (!prefixcmp(name, "refs/")) {
1184                return alloc_ref_from_str(name);
1185        }
1186
1187        if (!prefixcmp(name, "heads/") ||
1188            !prefixcmp(name, "tags/") ||
1189            !prefixcmp(name, "remotes/")) {
1190                ret = alloc_ref(strlen(name) + 6);
1191                sprintf(ret->name, "refs/%s", name);
1192                return ret;
1193        }
1194
1195        ret = alloc_ref(strlen(name) + 12);
1196        sprintf(ret->name, "refs/heads/%s", name);
1197        return ret;
1198}
1199
1200int get_fetch_map(const struct ref *remote_refs,
1201                  const struct refspec *refspec,
1202                  struct ref ***tail,
1203                  int missing_ok)
1204{
1205        struct ref *ref_map, **rmp;
1206
1207        if (refspec->pattern) {
1208                ref_map = get_expanded_map(remote_refs, refspec);
1209        } else {
1210                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1211
1212                ref_map = get_remote_ref(remote_refs, name);
1213                if (!missing_ok && !ref_map)
1214                        die("Couldn't find remote ref %s", name);
1215                if (ref_map) {
1216                        ref_map->peer_ref = get_local_ref(refspec->dst);
1217                        if (ref_map->peer_ref && refspec->force)
1218                                ref_map->peer_ref->force = 1;
1219                }
1220        }
1221
1222        for (rmp = &ref_map; *rmp; ) {
1223                if ((*rmp)->peer_ref) {
1224                        int st = check_ref_format((*rmp)->peer_ref->name + 5);
1225                        if (st && st != CHECK_REF_FORMAT_ONELEVEL) {
1226                                struct ref *ignore = *rmp;
1227                                error("* Ignoring funny ref '%s' locally",
1228                                      (*rmp)->peer_ref->name);
1229                                *rmp = (*rmp)->next;
1230                                free(ignore->peer_ref);
1231                                free(ignore);
1232                                continue;
1233                        }
1234                }
1235                rmp = &((*rmp)->next);
1236        }
1237
1238        if (ref_map)
1239                tail_link_ref(ref_map, tail);
1240
1241        return 0;
1242}
1243
1244int resolve_remote_symref(struct ref *ref, struct ref *list)
1245{
1246        if (!ref->symref)
1247                return 0;
1248        for (; list; list = list->next)
1249                if (!strcmp(ref->symref, list->name)) {
1250                        hashcpy(ref->old_sha1, list->old_sha1);
1251                        return 0;
1252                }
1253        return 1;
1254}
1255
1256/*
1257 * Return true if there is anything to report, otherwise false.
1258 */
1259int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
1260{
1261        unsigned char sha1[20];
1262        struct commit *ours, *theirs;
1263        char symmetric[84];
1264        struct rev_info revs;
1265        const char *rev_argv[10], *base;
1266        int rev_argc;
1267
1268        /*
1269         * Nothing to report unless we are marked to build on top of
1270         * somebody else.
1271         */
1272        if (!branch ||
1273            !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
1274                return 0;
1275
1276        /*
1277         * If what we used to build on no longer exists, there is
1278         * nothing to report.
1279         */
1280        base = branch->merge[0]->dst;
1281        if (!resolve_ref(base, sha1, 1, NULL))
1282                return 0;
1283        theirs = lookup_commit(sha1);
1284        if (!theirs)
1285                return 0;
1286
1287        if (!resolve_ref(branch->refname, sha1, 1, NULL))
1288                return 0;
1289        ours = lookup_commit(sha1);
1290        if (!ours)
1291                return 0;
1292
1293        /* are we the same? */
1294        if (theirs == ours)
1295                return 0;
1296
1297        /* Run "rev-list --left-right ours...theirs" internally... */
1298        rev_argc = 0;
1299        rev_argv[rev_argc++] = NULL;
1300        rev_argv[rev_argc++] = "--left-right";
1301        rev_argv[rev_argc++] = symmetric;
1302        rev_argv[rev_argc++] = "--";
1303        rev_argv[rev_argc] = NULL;
1304
1305        strcpy(symmetric, sha1_to_hex(ours->object.sha1));
1306        strcpy(symmetric + 40, "...");
1307        strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
1308
1309        init_revisions(&revs, NULL);
1310        setup_revisions(rev_argc, rev_argv, &revs, NULL);
1311        prepare_revision_walk(&revs);
1312
1313        /* ... and count the commits on each side. */
1314        *num_ours = 0;
1315        *num_theirs = 0;
1316        while (1) {
1317                struct commit *c = get_revision(&revs);
1318                if (!c)
1319                        break;
1320                if (c->object.flags & SYMMETRIC_LEFT)
1321                        (*num_ours)++;
1322                else
1323                        (*num_theirs)++;
1324        }
1325
1326        /* clear object flags smudged by the above traversal */
1327        clear_commit_marks(ours, ALL_REV_FLAGS);
1328        clear_commit_marks(theirs, ALL_REV_FLAGS);
1329        return 1;
1330}
1331
1332/*
1333 * Return true when there is anything to report, otherwise false.
1334 */
1335int format_tracking_info(struct branch *branch, struct strbuf *sb)
1336{
1337        int num_ours, num_theirs;
1338        const char *base;
1339
1340        if (!stat_tracking_info(branch, &num_ours, &num_theirs))
1341                return 0;
1342
1343        base = branch->merge[0]->dst;
1344        if (!prefixcmp(base, "refs/remotes/")) {
1345                base += strlen("refs/remotes/");
1346        }
1347        if (!num_theirs)
1348                strbuf_addf(sb, "Your branch is ahead of '%s' "
1349                            "by %d commit%s.\n",
1350                            base, num_ours, (num_ours == 1) ? "" : "s");
1351        else if (!num_ours)
1352                strbuf_addf(sb, "Your branch is behind '%s' "
1353                            "by %d commit%s, "
1354                            "and can be fast-forwarded.\n",
1355                            base, num_theirs, (num_theirs == 1) ? "" : "s");
1356        else
1357                strbuf_addf(sb, "Your branch and '%s' have diverged,\n"
1358                            "and have %d and %d different commit(s) each, "
1359                            "respectively.\n",
1360                            base, num_ours, num_theirs);
1361        return 1;
1362}