remote.con commit Use the matching function to generate the match results (e928213)
   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#include "dir.h"
   8
   9static struct refspec s_tag_refspec = {
  10        0,
  11        1,
  12        0,
  13        "refs/tags/",
  14        "refs/tags/"
  15};
  16
  17const struct refspec *tag_refspec = &s_tag_refspec;
  18
  19struct counted_string {
  20        size_t len;
  21        const char *s;
  22};
  23struct rewrite {
  24        const char *base;
  25        size_t baselen;
  26        struct counted_string *instead_of;
  27        int instead_of_nr;
  28        int instead_of_alloc;
  29};
  30
  31static struct remote **remotes;
  32static int remotes_alloc;
  33static int remotes_nr;
  34
  35static struct branch **branches;
  36static int branches_alloc;
  37static int branches_nr;
  38
  39static struct branch *current_branch;
  40static const char *default_remote_name;
  41
  42static struct rewrite **rewrite;
  43static int rewrite_alloc;
  44static int rewrite_nr;
  45
  46#define BUF_SIZE (2048)
  47static char buffer[BUF_SIZE];
  48
  49static const char *alias_url(const char *url)
  50{
  51        int i, j;
  52        char *ret;
  53        struct counted_string *longest;
  54        int longest_i;
  55
  56        longest = NULL;
  57        longest_i = -1;
  58        for (i = 0; i < rewrite_nr; i++) {
  59                if (!rewrite[i])
  60                        continue;
  61                for (j = 0; j < rewrite[i]->instead_of_nr; j++) {
  62                        if (!prefixcmp(url, rewrite[i]->instead_of[j].s) &&
  63                            (!longest ||
  64                             longest->len < rewrite[i]->instead_of[j].len)) {
  65                                longest = &(rewrite[i]->instead_of[j]);
  66                                longest_i = i;
  67                        }
  68                }
  69        }
  70        if (!longest)
  71                return url;
  72
  73        ret = xmalloc(rewrite[longest_i]->baselen +
  74                     (strlen(url) - longest->len) + 1);
  75        strcpy(ret, rewrite[longest_i]->base);
  76        strcpy(ret + rewrite[longest_i]->baselen, url + longest->len);
  77        return ret;
  78}
  79
  80static void add_push_refspec(struct remote *remote, const char *ref)
  81{
  82        ALLOC_GROW(remote->push_refspec,
  83                   remote->push_refspec_nr + 1,
  84                   remote->push_refspec_alloc);
  85        remote->push_refspec[remote->push_refspec_nr++] = ref;
  86}
  87
  88static void add_fetch_refspec(struct remote *remote, const char *ref)
  89{
  90        ALLOC_GROW(remote->fetch_refspec,
  91                   remote->fetch_refspec_nr + 1,
  92                   remote->fetch_refspec_alloc);
  93        remote->fetch_refspec[remote->fetch_refspec_nr++] = ref;
  94}
  95
  96static void add_url(struct remote *remote, const char *url)
  97{
  98        ALLOC_GROW(remote->url, remote->url_nr + 1, remote->url_alloc);
  99        remote->url[remote->url_nr++] = url;
 100}
 101
 102static void add_url_alias(struct remote *remote, const char *url)
 103{
 104        add_url(remote, alias_url(url));
 105}
 106
 107static struct remote *make_remote(const char *name, int len)
 108{
 109        struct remote *ret;
 110        int i;
 111
 112        for (i = 0; i < remotes_nr; i++) {
 113                if (len ? (!strncmp(name, remotes[i]->name, len) &&
 114                           !remotes[i]->name[len]) :
 115                    !strcmp(name, remotes[i]->name))
 116                        return remotes[i];
 117        }
 118
 119        ret = xcalloc(1, sizeof(struct remote));
 120        ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 121        remotes[remotes_nr++] = ret;
 122        if (len)
 123                ret->name = xstrndup(name, len);
 124        else
 125                ret->name = xstrdup(name);
 126        return ret;
 127}
 128
 129static void add_merge(struct branch *branch, const char *name)
 130{
 131        ALLOC_GROW(branch->merge_name, branch->merge_nr + 1,
 132                   branch->merge_alloc);
 133        branch->merge_name[branch->merge_nr++] = name;
 134}
 135
 136static struct branch *make_branch(const char *name, int len)
 137{
 138        struct branch *ret;
 139        int i;
 140        char *refname;
 141
 142        for (i = 0; i < branches_nr; i++) {
 143                if (len ? (!strncmp(name, branches[i]->name, len) &&
 144                           !branches[i]->name[len]) :
 145                    !strcmp(name, branches[i]->name))
 146                        return branches[i];
 147        }
 148
 149        ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 150        ret = xcalloc(1, sizeof(struct branch));
 151        branches[branches_nr++] = ret;
 152        if (len)
 153                ret->name = xstrndup(name, len);
 154        else
 155                ret->name = xstrdup(name);
 156        refname = xmalloc(strlen(name) + strlen("refs/heads/") + 1);
 157        strcpy(refname, "refs/heads/");
 158        strcpy(refname + strlen("refs/heads/"), ret->name);
 159        ret->refname = refname;
 160
 161        return ret;
 162}
 163
 164static struct rewrite *make_rewrite(const char *base, int len)
 165{
 166        struct rewrite *ret;
 167        int i;
 168
 169        for (i = 0; i < rewrite_nr; i++) {
 170                if (len
 171                    ? (len == rewrite[i]->baselen &&
 172                       !strncmp(base, rewrite[i]->base, len))
 173                    : !strcmp(base, rewrite[i]->base))
 174                        return rewrite[i];
 175        }
 176
 177        ALLOC_GROW(rewrite, rewrite_nr + 1, rewrite_alloc);
 178        ret = xcalloc(1, sizeof(struct rewrite));
 179        rewrite[rewrite_nr++] = ret;
 180        if (len) {
 181                ret->base = xstrndup(base, len);
 182                ret->baselen = len;
 183        }
 184        else {
 185                ret->base = xstrdup(base);
 186                ret->baselen = strlen(base);
 187        }
 188        return ret;
 189}
 190
 191static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 192{
 193        ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 194        rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 195        rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 196        rewrite->instead_of_nr++;
 197}
 198
 199static void read_remotes_file(struct remote *remote)
 200{
 201        FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
 202
 203        if (!f)
 204                return;
 205        remote->origin = REMOTE_REMOTES;
 206        while (fgets(buffer, BUF_SIZE, f)) {
 207                int value_list;
 208                char *s, *p;
 209
 210                if (!prefixcmp(buffer, "URL:")) {
 211                        value_list = 0;
 212                        s = buffer + 4;
 213                } else if (!prefixcmp(buffer, "Push:")) {
 214                        value_list = 1;
 215                        s = buffer + 5;
 216                } else if (!prefixcmp(buffer, "Pull:")) {
 217                        value_list = 2;
 218                        s = buffer + 5;
 219                } else
 220                        continue;
 221
 222                while (isspace(*s))
 223                        s++;
 224                if (!*s)
 225                        continue;
 226
 227                p = s + strlen(s);
 228                while (isspace(p[-1]))
 229                        *--p = 0;
 230
 231                switch (value_list) {
 232                case 0:
 233                        add_url_alias(remote, xstrdup(s));
 234                        break;
 235                case 1:
 236                        add_push_refspec(remote, xstrdup(s));
 237                        break;
 238                case 2:
 239                        add_fetch_refspec(remote, xstrdup(s));
 240                        break;
 241                }
 242        }
 243        fclose(f);
 244}
 245
 246static void read_branches_file(struct remote *remote)
 247{
 248        const char *slash = strchr(remote->name, '/');
 249        char *frag;
 250        struct strbuf branch = STRBUF_INIT;
 251        int n = slash ? slash - remote->name : 1000;
 252        FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 253        char *s, *p;
 254        int len;
 255
 256        if (!f)
 257                return;
 258        s = fgets(buffer, BUF_SIZE, f);
 259        fclose(f);
 260        if (!s)
 261                return;
 262        while (isspace(*s))
 263                s++;
 264        if (!*s)
 265                return;
 266        remote->origin = REMOTE_BRANCHES;
 267        p = s + strlen(s);
 268        while (isspace(p[-1]))
 269                *--p = 0;
 270        len = p - s;
 271        if (slash)
 272                len += strlen(slash);
 273        p = xmalloc(len + 1);
 274        strcpy(p, s);
 275        if (slash)
 276                strcat(p, slash);
 277
 278        /*
 279         * With "slash", e.g. "git fetch jgarzik/netdev-2.6" when
 280         * reading from $GIT_DIR/branches/jgarzik fetches "HEAD" from
 281         * the partial URL obtained from the branches file plus
 282         * "/netdev-2.6" and does not store it in any tracking ref.
 283         * #branch specifier in the file is ignored.
 284         *
 285         * Otherwise, the branches file would have URL and optionally
 286         * #branch specified.  The "master" (or specified) branch is
 287         * fetched and stored in the local branch of the same name.
 288         */
 289        frag = strchr(p, '#');
 290        if (frag) {
 291                *(frag++) = '\0';
 292                strbuf_addf(&branch, "refs/heads/%s", frag);
 293        } else
 294                strbuf_addstr(&branch, "refs/heads/master");
 295        if (!slash) {
 296                strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 297        } else {
 298                strbuf_reset(&branch);
 299                strbuf_addstr(&branch, "HEAD:");
 300        }
 301        add_url_alias(remote, p);
 302        add_fetch_refspec(remote, strbuf_detach(&branch, 0));
 303        /*
 304         * Cogito compatible push: push current HEAD to remote #branch
 305         * (master if missing)
 306         */
 307        strbuf_init(&branch, 0);
 308        strbuf_addstr(&branch, "HEAD");
 309        if (frag)
 310                strbuf_addf(&branch, ":refs/heads/%s", frag);
 311        else
 312                strbuf_addstr(&branch, ":refs/heads/master");
 313        add_push_refspec(remote, strbuf_detach(&branch, 0));
 314        remote->fetch_tags = 1; /* always auto-follow */
 315}
 316
 317static int handle_config(const char *key, const char *value, void *cb)
 318{
 319        const char *name;
 320        const char *subkey;
 321        struct remote *remote;
 322        struct branch *branch;
 323        if (!prefixcmp(key, "branch.")) {
 324                name = key + 7;
 325                subkey = strrchr(name, '.');
 326                if (!subkey)
 327                        return 0;
 328                branch = make_branch(name, subkey - name);
 329                if (!strcmp(subkey, ".remote")) {
 330                        if (!value)
 331                                return config_error_nonbool(key);
 332                        branch->remote_name = xstrdup(value);
 333                        if (branch == current_branch)
 334                                default_remote_name = branch->remote_name;
 335                } else if (!strcmp(subkey, ".merge")) {
 336                        if (!value)
 337                                return config_error_nonbool(key);
 338                        add_merge(branch, xstrdup(value));
 339                }
 340                return 0;
 341        }
 342        if (!prefixcmp(key, "url.")) {
 343                struct rewrite *rewrite;
 344                name = key + 4;
 345                subkey = strrchr(name, '.');
 346                if (!subkey)
 347                        return 0;
 348                rewrite = make_rewrite(name, subkey - name);
 349                if (!strcmp(subkey, ".insteadof")) {
 350                        if (!value)
 351                                return config_error_nonbool(key);
 352                        add_instead_of(rewrite, xstrdup(value));
 353                }
 354        }
 355        if (prefixcmp(key,  "remote."))
 356                return 0;
 357        name = key + 7;
 358        if (*name == '/') {
 359                warning("Config remote shorthand cannot begin with '/': %s",
 360                        name);
 361                return 0;
 362        }
 363        subkey = strrchr(name, '.');
 364        if (!subkey)
 365                return error("Config with no key for remote %s", name);
 366        remote = make_remote(name, subkey - name);
 367        remote->origin = REMOTE_CONFIG;
 368        if (!strcmp(subkey, ".mirror"))
 369                remote->mirror = git_config_bool(key, value);
 370        else if (!strcmp(subkey, ".skipdefaultupdate"))
 371                remote->skip_default_update = git_config_bool(key, value);
 372
 373        else if (!strcmp(subkey, ".url")) {
 374                const char *v;
 375                if (git_config_string(&v, key, value))
 376                        return -1;
 377                add_url(remote, v);
 378        } else if (!strcmp(subkey, ".push")) {
 379                const char *v;
 380                if (git_config_string(&v, key, value))
 381                        return -1;
 382                add_push_refspec(remote, v);
 383        } else if (!strcmp(subkey, ".fetch")) {
 384                const char *v;
 385                if (git_config_string(&v, key, value))
 386                        return -1;
 387                add_fetch_refspec(remote, v);
 388        } else if (!strcmp(subkey, ".receivepack")) {
 389                const char *v;
 390                if (git_config_string(&v, key, value))
 391                        return -1;
 392                if (!remote->receivepack)
 393                        remote->receivepack = v;
 394                else
 395                        error("more than one receivepack given, using the first");
 396        } else if (!strcmp(subkey, ".uploadpack")) {
 397                const char *v;
 398                if (git_config_string(&v, key, value))
 399                        return -1;
 400                if (!remote->uploadpack)
 401                        remote->uploadpack = v;
 402                else
 403                        error("more than one uploadpack given, using the first");
 404        } else if (!strcmp(subkey, ".tagopt")) {
 405                if (!strcmp(value, "--no-tags"))
 406                        remote->fetch_tags = -1;
 407        } else if (!strcmp(subkey, ".proxy")) {
 408                return git_config_string((const char **)&remote->http_proxy,
 409                                         key, value);
 410        }
 411        return 0;
 412}
 413
 414static void alias_all_urls(void)
 415{
 416        int i, j;
 417        for (i = 0; i < remotes_nr; i++) {
 418                if (!remotes[i])
 419                        continue;
 420                for (j = 0; j < remotes[i]->url_nr; j++) {
 421                        remotes[i]->url[j] = alias_url(remotes[i]->url[j]);
 422                }
 423        }
 424}
 425
 426static void read_config(void)
 427{
 428        unsigned char sha1[20];
 429        const char *head_ref;
 430        int flag;
 431        if (default_remote_name) // did this already
 432                return;
 433        default_remote_name = xstrdup("origin");
 434        current_branch = NULL;
 435        head_ref = resolve_ref("HEAD", sha1, 0, &flag);
 436        if (head_ref && (flag & REF_ISSYMREF) &&
 437            !prefixcmp(head_ref, "refs/heads/")) {
 438                current_branch =
 439                        make_branch(head_ref + strlen("refs/heads/"), 0);
 440        }
 441        git_config(handle_config, NULL);
 442        alias_all_urls();
 443}
 444
 445/*
 446 * We need to make sure the tracking branches are well formed, but a
 447 * wildcard refspec in "struct refspec" must have a trailing slash. We
 448 * temporarily drop the trailing '/' while calling check_ref_format(),
 449 * and put it back.  The caller knows that a CHECK_REF_FORMAT_ONELEVEL
 450 * error return is Ok for a wildcard refspec.
 451 */
 452static int verify_refname(char *name, int is_glob)
 453{
 454        int result, len = -1;
 455
 456        if (is_glob) {
 457                len = strlen(name);
 458                assert(name[len - 1] == '/');
 459                name[len - 1] = '\0';
 460        }
 461        result = check_ref_format(name);
 462        if (is_glob)
 463                name[len - 1] = '/';
 464        return result;
 465}
 466
 467/*
 468 * This function frees a refspec array.
 469 * Warning: code paths should be checked to ensure that the src
 470 *          and dst pointers are always freeable pointers as well
 471 *          as the refspec pointer itself.
 472 */
 473static void free_refspecs(struct refspec *refspec, int nr_refspec)
 474{
 475        int i;
 476
 477        if (!refspec)
 478                return;
 479
 480        for (i = 0; i < nr_refspec; i++) {
 481                free(refspec[i].src);
 482                free(refspec[i].dst);
 483        }
 484        free(refspec);
 485}
 486
 487static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 488{
 489        int i;
 490        int st;
 491        struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 492
 493        for (i = 0; i < nr_refspec; i++) {
 494                size_t llen;
 495                int is_glob;
 496                const char *lhs, *rhs;
 497
 498                llen = is_glob = 0;
 499
 500                lhs = refspec[i];
 501                if (*lhs == '+') {
 502                        rs[i].force = 1;
 503                        lhs++;
 504                }
 505
 506                rhs = strrchr(lhs, ':');
 507
 508                /*
 509                 * Before going on, special case ":" (or "+:") as a refspec
 510                 * for matching refs.
 511                 */
 512                if (!fetch && rhs == lhs && rhs[1] == '\0') {
 513                        rs[i].matching = 1;
 514                        continue;
 515                }
 516
 517                if (rhs) {
 518                        size_t rlen = strlen(++rhs);
 519                        is_glob = (2 <= rlen && !strcmp(rhs + rlen - 2, "/*"));
 520                        rs[i].dst = xstrndup(rhs, rlen - is_glob);
 521                }
 522
 523                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 524                if (2 <= llen && !memcmp(lhs + llen - 2, "/*", 2)) {
 525                        if ((rhs && !is_glob) || (!rhs && fetch))
 526                                goto invalid;
 527                        is_glob = 1;
 528                        llen--;
 529                } else if (rhs && is_glob) {
 530                        goto invalid;
 531                }
 532
 533                rs[i].pattern = is_glob;
 534                rs[i].src = xstrndup(lhs, llen);
 535
 536                if (fetch) {
 537                        /*
 538                         * LHS
 539                         * - empty is allowed; it means HEAD.
 540                         * - otherwise it must be a valid looking ref.
 541                         */
 542                        if (!*rs[i].src)
 543                                ; /* empty is ok */
 544                        else {
 545                                st = verify_refname(rs[i].src, is_glob);
 546                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 547                                        goto invalid;
 548                        }
 549                        /*
 550                         * RHS
 551                         * - missing is ok, and is same as empty.
 552                         * - empty is ok; it means not to store.
 553                         * - otherwise it must be a valid looking ref.
 554                         */
 555                        if (!rs[i].dst) {
 556                                ; /* ok */
 557                        } else if (!*rs[i].dst) {
 558                                ; /* ok */
 559                        } else {
 560                                st = verify_refname(rs[i].dst, is_glob);
 561                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 562                                        goto invalid;
 563                        }
 564                } else {
 565                        /*
 566                         * LHS
 567                         * - empty is allowed; it means delete.
 568                         * - when wildcarded, it must be a valid looking ref.
 569                         * - otherwise, it must be an extended SHA-1, but
 570                         *   there is no existing way to validate this.
 571                         */
 572                        if (!*rs[i].src)
 573                                ; /* empty is ok */
 574                        else if (is_glob) {
 575                                st = verify_refname(rs[i].src, is_glob);
 576                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 577                                        goto invalid;
 578                        }
 579                        else
 580                                ; /* anything goes, for now */
 581                        /*
 582                         * RHS
 583                         * - missing is allowed, but LHS then must be a
 584                         *   valid looking ref.
 585                         * - empty is not allowed.
 586                         * - otherwise it must be a valid looking ref.
 587                         */
 588                        if (!rs[i].dst) {
 589                                st = verify_refname(rs[i].src, is_glob);
 590                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 591                                        goto invalid;
 592                        } else if (!*rs[i].dst) {
 593                                goto invalid;
 594                        } else {
 595                                st = verify_refname(rs[i].dst, is_glob);
 596                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 597                                        goto invalid;
 598                        }
 599                }
 600        }
 601        return rs;
 602
 603 invalid:
 604        if (verify) {
 605                /*
 606                 * nr_refspec must be greater than zero and i must be valid
 607                 * since it is only possible to reach this point from within
 608                 * the for loop above.
 609                 */
 610                free_refspecs(rs, i+1);
 611                return NULL;
 612        }
 613        die("Invalid refspec '%s'", refspec[i]);
 614}
 615
 616int valid_fetch_refspec(const char *fetch_refspec_str)
 617{
 618        const char *fetch_refspec[] = { fetch_refspec_str };
 619        struct refspec *refspec;
 620
 621        refspec = parse_refspec_internal(1, fetch_refspec, 1, 1);
 622        free_refspecs(refspec, 1);
 623        return !!refspec;
 624}
 625
 626struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 627{
 628        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 629}
 630
 631static struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 632{
 633        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 634}
 635
 636static int valid_remote_nick(const char *name)
 637{
 638        if (!name[0] || is_dot_or_dotdot(name))
 639                return 0;
 640        return !strchr(name, '/'); /* no slash */
 641}
 642
 643struct remote *remote_get(const char *name)
 644{
 645        struct remote *ret;
 646
 647        read_config();
 648        if (!name)
 649                name = default_remote_name;
 650        ret = make_remote(name, 0);
 651        if (valid_remote_nick(name)) {
 652                if (!ret->url)
 653                        read_remotes_file(ret);
 654                if (!ret->url)
 655                        read_branches_file(ret);
 656        }
 657        if (!ret->url)
 658                add_url_alias(ret, name);
 659        if (!ret->url)
 660                return NULL;
 661        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 662        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 663        return ret;
 664}
 665
 666int for_each_remote(each_remote_fn fn, void *priv)
 667{
 668        int i, result = 0;
 669        read_config();
 670        for (i = 0; i < remotes_nr && !result; i++) {
 671                struct remote *r = remotes[i];
 672                if (!r)
 673                        continue;
 674                if (!r->fetch)
 675                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 676                                                       r->fetch_refspec);
 677                if (!r->push)
 678                        r->push = parse_push_refspec(r->push_refspec_nr,
 679                                                     r->push_refspec);
 680                result = fn(r, priv);
 681        }
 682        return result;
 683}
 684
 685void ref_remove_duplicates(struct ref *ref_map)
 686{
 687        struct ref **posn;
 688        struct ref *next;
 689        for (; ref_map; ref_map = ref_map->next) {
 690                if (!ref_map->peer_ref)
 691                        continue;
 692                posn = &ref_map->next;
 693                while (*posn) {
 694                        if ((*posn)->peer_ref &&
 695                            !strcmp((*posn)->peer_ref->name,
 696                                    ref_map->peer_ref->name)) {
 697                                if (strcmp((*posn)->name, ref_map->name))
 698                                        die("%s tracks both %s and %s",
 699                                            ref_map->peer_ref->name,
 700                                            (*posn)->name, ref_map->name);
 701                                next = (*posn)->next;
 702                                free((*posn)->peer_ref);
 703                                free(*posn);
 704                                *posn = next;
 705                        } else {
 706                                posn = &(*posn)->next;
 707                        }
 708                }
 709        }
 710}
 711
 712int remote_has_url(struct remote *remote, const char *url)
 713{
 714        int i;
 715        for (i = 0; i < remote->url_nr; i++) {
 716                if (!strcmp(remote->url[i], url))
 717                        return 1;
 718        }
 719        return 0;
 720}
 721
 722static int match_name_with_pattern(const char *key, const char *name,
 723                                   const char *value, char **result)
 724{
 725        size_t klen = strlen(key);
 726        int ret = !strncmp(key, name, klen);
 727        if (ret && value) {
 728                size_t vlen = strlen(value);
 729                *result = xmalloc(vlen +
 730                                  strlen(name) -
 731                                  klen + 1);
 732                strcpy(*result, value);
 733                strcpy(*result + vlen, name + klen);
 734        }
 735        return ret;
 736}
 737
 738int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 739{
 740        int find_src = refspec->src == NULL;
 741        char *needle, **result;
 742        int i;
 743
 744        if (find_src) {
 745                if (!refspec->dst)
 746                        return error("find_tracking: need either src or dst");
 747                needle = refspec->dst;
 748                result = &refspec->src;
 749        } else {
 750                needle = refspec->src;
 751                result = &refspec->dst;
 752        }
 753
 754        for (i = 0; i < remote->fetch_refspec_nr; i++) {
 755                struct refspec *fetch = &remote->fetch[i];
 756                const char *key = find_src ? fetch->dst : fetch->src;
 757                const char *value = find_src ? fetch->src : fetch->dst;
 758                if (!fetch->dst)
 759                        continue;
 760                if (fetch->pattern) {
 761                        if (match_name_with_pattern(key, needle, value, result)) {
 762                                refspec->force = fetch->force;
 763                                return 0;
 764                        }
 765                } else if (!strcmp(needle, key)) {
 766                        *result = xstrdup(value);
 767                        refspec->force = fetch->force;
 768                        return 0;
 769                }
 770        }
 771        return -1;
 772}
 773
 774static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 775                const char *name)
 776{
 777        size_t len = strlen(name);
 778        struct ref *ref = xcalloc(1, sizeof(struct ref) + prefixlen + len + 1);
 779        memcpy(ref->name, prefix, prefixlen);
 780        memcpy(ref->name + prefixlen, name, len);
 781        return ref;
 782}
 783
 784struct ref *alloc_ref(const char *name)
 785{
 786        return alloc_ref_with_prefix("", 0, name);
 787}
 788
 789static struct ref *copy_ref(const struct ref *ref)
 790{
 791        struct ref *ret = xmalloc(sizeof(struct ref) + strlen(ref->name) + 1);
 792        memcpy(ret, ref, sizeof(struct ref) + strlen(ref->name) + 1);
 793        ret->next = NULL;
 794        return ret;
 795}
 796
 797struct ref *copy_ref_list(const struct ref *ref)
 798{
 799        struct ref *ret = NULL;
 800        struct ref **tail = &ret;
 801        while (ref) {
 802                *tail = copy_ref(ref);
 803                ref = ref->next;
 804                tail = &((*tail)->next);
 805        }
 806        return ret;
 807}
 808
 809static void free_ref(struct ref *ref)
 810{
 811        if (!ref)
 812                return;
 813        free(ref->remote_status);
 814        free(ref->symref);
 815        free(ref);
 816}
 817
 818void free_refs(struct ref *ref)
 819{
 820        struct ref *next;
 821        while (ref) {
 822                next = ref->next;
 823                free(ref->peer_ref);
 824                free_ref(ref);
 825                ref = next;
 826        }
 827}
 828
 829static int count_refspec_match(const char *pattern,
 830                               struct ref *refs,
 831                               struct ref **matched_ref)
 832{
 833        int patlen = strlen(pattern);
 834        struct ref *matched_weak = NULL;
 835        struct ref *matched = NULL;
 836        int weak_match = 0;
 837        int match = 0;
 838
 839        for (weak_match = match = 0; refs; refs = refs->next) {
 840                char *name = refs->name;
 841                int namelen = strlen(name);
 842
 843                if (!refname_match(pattern, name, ref_rev_parse_rules))
 844                        continue;
 845
 846                /* A match is "weak" if it is with refs outside
 847                 * heads or tags, and did not specify the pattern
 848                 * in full (e.g. "refs/remotes/origin/master") or at
 849                 * least from the toplevel (e.g. "remotes/origin/master");
 850                 * otherwise "git push $URL master" would result in
 851                 * ambiguity between remotes/origin/master and heads/master
 852                 * at the remote site.
 853                 */
 854                if (namelen != patlen &&
 855                    patlen != namelen - 5 &&
 856                    prefixcmp(name, "refs/heads/") &&
 857                    prefixcmp(name, "refs/tags/")) {
 858                        /* We want to catch the case where only weak
 859                         * matches are found and there are multiple
 860                         * matches, and where more than one strong
 861                         * matches are found, as ambiguous.  One
 862                         * strong match with zero or more weak matches
 863                         * are acceptable as a unique match.
 864                         */
 865                        matched_weak = refs;
 866                        weak_match++;
 867                }
 868                else {
 869                        matched = refs;
 870                        match++;
 871                }
 872        }
 873        if (!matched) {
 874                *matched_ref = matched_weak;
 875                return weak_match;
 876        }
 877        else {
 878                *matched_ref = matched;
 879                return match;
 880        }
 881}
 882
 883static void tail_link_ref(struct ref *ref, struct ref ***tail)
 884{
 885        **tail = ref;
 886        while (ref->next)
 887                ref = ref->next;
 888        *tail = &ref->next;
 889}
 890
 891static struct ref *try_explicit_object_name(const char *name)
 892{
 893        unsigned char sha1[20];
 894        struct ref *ref;
 895
 896        if (!*name) {
 897                ref = alloc_ref("(delete)");
 898                hashclr(ref->new_sha1);
 899                return ref;
 900        }
 901        if (get_sha1(name, sha1))
 902                return NULL;
 903        ref = alloc_ref(name);
 904        hashcpy(ref->new_sha1, sha1);
 905        return ref;
 906}
 907
 908static struct ref *make_linked_ref(const char *name, struct ref ***tail)
 909{
 910        struct ref *ret = alloc_ref(name);
 911        tail_link_ref(ret, tail);
 912        return ret;
 913}
 914
 915static char *guess_ref(const char *name, struct ref *peer)
 916{
 917        struct strbuf buf = STRBUF_INIT;
 918        unsigned char sha1[20];
 919
 920        const char *r = resolve_ref(peer->name, sha1, 1, NULL);
 921        if (!r)
 922                return NULL;
 923
 924        if (!prefixcmp(r, "refs/heads/"))
 925                strbuf_addstr(&buf, "refs/heads/");
 926        else if (!prefixcmp(r, "refs/tags/"))
 927                strbuf_addstr(&buf, "refs/tags/");
 928        else
 929                return NULL;
 930
 931        strbuf_addstr(&buf, name);
 932        return strbuf_detach(&buf, NULL);
 933}
 934
 935static int match_explicit(struct ref *src, struct ref *dst,
 936                          struct ref ***dst_tail,
 937                          struct refspec *rs)
 938{
 939        struct ref *matched_src, *matched_dst;
 940
 941        const char *dst_value = rs->dst;
 942        char *dst_guess;
 943
 944        if (rs->pattern || rs->matching)
 945                return 0;
 946
 947        matched_src = matched_dst = NULL;
 948        switch (count_refspec_match(rs->src, src, &matched_src)) {
 949        case 1:
 950                break;
 951        case 0:
 952                /* The source could be in the get_sha1() format
 953                 * not a reference name.  :refs/other is a
 954                 * way to delete 'other' ref at the remote end.
 955                 */
 956                matched_src = try_explicit_object_name(rs->src);
 957                if (!matched_src)
 958                        return error("src refspec %s does not match any.", rs->src);
 959                break;
 960        default:
 961                return error("src refspec %s matches more than one.", rs->src);
 962        }
 963
 964        if (!dst_value) {
 965                unsigned char sha1[20];
 966                int flag;
 967
 968                dst_value = resolve_ref(matched_src->name, sha1, 1, &flag);
 969                if (!dst_value ||
 970                    ((flag & REF_ISSYMREF) &&
 971                     prefixcmp(dst_value, "refs/heads/")))
 972                        die("%s cannot be resolved to branch.",
 973                            matched_src->name);
 974        }
 975
 976        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
 977        case 1:
 978                break;
 979        case 0:
 980                if (!memcmp(dst_value, "refs/", 5))
 981                        matched_dst = make_linked_ref(dst_value, dst_tail);
 982                else if((dst_guess = guess_ref(dst_value, matched_src)))
 983                        matched_dst = make_linked_ref(dst_guess, dst_tail);
 984                else
 985                        error("unable to push to unqualified destination: %s\n"
 986                              "The destination refspec neither matches an "
 987                              "existing ref on the remote nor\n"
 988                              "begins with refs/, and we are unable to "
 989                              "guess a prefix based on the source ref.",
 990                              dst_value);
 991                break;
 992        default:
 993                matched_dst = NULL;
 994                error("dst refspec %s matches more than one.",
 995                      dst_value);
 996                break;
 997        }
 998        if (!matched_dst)
 999                return -1;
1000        if (matched_dst->peer_ref)
1001                return error("dst ref %s receives from more than one src.",
1002                      matched_dst->name);
1003        else {
1004                matched_dst->peer_ref = matched_src;
1005                matched_dst->force = rs->force;
1006        }
1007        return 0;
1008}
1009
1010static int match_explicit_refs(struct ref *src, struct ref *dst,
1011                               struct ref ***dst_tail, struct refspec *rs,
1012                               int rs_nr)
1013{
1014        int i, errs;
1015        for (i = errs = 0; i < rs_nr; i++)
1016                errs += match_explicit(src, dst, dst_tail, &rs[i]);
1017        return errs;
1018}
1019
1020static const struct refspec *check_pattern_match(const struct refspec *rs,
1021                                                 int rs_nr,
1022                                                 const struct ref *src)
1023{
1024        int i;
1025        int matching_refs = -1;
1026        for (i = 0; i < rs_nr; i++) {
1027                if (rs[i].matching &&
1028                    (matching_refs == -1 || rs[i].force)) {
1029                        matching_refs = i;
1030                        continue;
1031                }
1032
1033                if (rs[i].pattern && match_name_with_pattern(rs[i].src, src->name,
1034                                                             NULL, NULL))
1035                        return rs + i;
1036        }
1037        if (matching_refs != -1)
1038                return rs + matching_refs;
1039        else
1040                return NULL;
1041}
1042
1043/*
1044 * Note. This is used only by "push"; refspec matching rules for
1045 * push and fetch are subtly different, so do not try to reuse it
1046 * without thinking.
1047 */
1048int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
1049               int nr_refspec, const char **refspec, int flags)
1050{
1051        struct refspec *rs;
1052        int send_all = flags & MATCH_REFS_ALL;
1053        int send_mirror = flags & MATCH_REFS_MIRROR;
1054        static const char *default_refspec[] = { ":", 0 };
1055
1056        if (!nr_refspec) {
1057                nr_refspec = 1;
1058                refspec = default_refspec;
1059        }
1060        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1061        if (match_explicit_refs(src, dst, dst_tail, rs, nr_refspec))
1062                return -1;
1063
1064        /* pick the remainder */
1065        for ( ; src; src = src->next) {
1066                struct ref *dst_peer;
1067                const struct refspec *pat = NULL;
1068                char *dst_name;
1069                if (src->peer_ref)
1070                        continue;
1071
1072                pat = check_pattern_match(rs, nr_refspec, src);
1073                if (!pat)
1074                        continue;
1075
1076                if (pat->matching) {
1077                        /*
1078                         * "matching refs"; traditionally we pushed everything
1079                         * including refs outside refs/heads/ hierarchy, but
1080                         * that does not make much sense these days.
1081                         */
1082                        if (!send_mirror && prefixcmp(src->name, "refs/heads/"))
1083                                continue;
1084                        dst_name = xstrdup(src->name);
1085
1086                } else {
1087                        const char *dst_side = pat->dst ? pat->dst : pat->src;
1088                        if (!match_name_with_pattern(pat->src, src->name,
1089                                                     dst_side, &dst_name))
1090                                die("Didn't think it matches any more");
1091                }
1092                dst_peer = find_ref_by_name(dst, dst_name);
1093                if (dst_peer) {
1094                        if (dst_peer->peer_ref)
1095                                /* We're already sending something to this ref. */
1096                                goto free_name;
1097
1098                } else {
1099                        if (pat->matching && !(send_all || send_mirror))
1100                                /*
1101                                 * Remote doesn't have it, and we have no
1102                                 * explicit pattern, and we don't have
1103                                 * --all nor --mirror.
1104                                 */
1105                                goto free_name;
1106
1107                        /* Create a new one and link it */
1108                        dst_peer = make_linked_ref(dst_name, dst_tail);
1109                        hashcpy(dst_peer->new_sha1, src->new_sha1);
1110                }
1111                dst_peer->peer_ref = src;
1112                dst_peer->force = pat->force;
1113        free_name:
1114                free(dst_name);
1115        }
1116        return 0;
1117}
1118
1119struct branch *branch_get(const char *name)
1120{
1121        struct branch *ret;
1122
1123        read_config();
1124        if (!name || !*name || !strcmp(name, "HEAD"))
1125                ret = current_branch;
1126        else
1127                ret = make_branch(name, 0);
1128        if (ret && ret->remote_name) {
1129                ret->remote = remote_get(ret->remote_name);
1130                if (ret->merge_nr) {
1131                        int i;
1132                        ret->merge = xcalloc(sizeof(*ret->merge),
1133                                             ret->merge_nr);
1134                        for (i = 0; i < ret->merge_nr; i++) {
1135                                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1136                                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1137                                remote_find_tracking(ret->remote,
1138                                                     ret->merge[i]);
1139                        }
1140                }
1141        }
1142        return ret;
1143}
1144
1145int branch_has_merge_config(struct branch *branch)
1146{
1147        return branch && !!branch->merge;
1148}
1149
1150int branch_merge_matches(struct branch *branch,
1151                                 int i,
1152                                 const char *refname)
1153{
1154        if (!branch || i < 0 || i >= branch->merge_nr)
1155                return 0;
1156        return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
1157}
1158
1159static struct ref *get_expanded_map(const struct ref *remote_refs,
1160                                    const struct refspec *refspec)
1161{
1162        const struct ref *ref;
1163        struct ref *ret = NULL;
1164        struct ref **tail = &ret;
1165
1166        char *expn_name;
1167
1168        for (ref = remote_refs; ref; ref = ref->next) {
1169                if (strchr(ref->name, '^'))
1170                        continue; /* a dereference item */
1171                if (match_name_with_pattern(refspec->src, ref->name,
1172                                            refspec->dst, &expn_name)) {
1173                        struct ref *cpy = copy_ref(ref);
1174
1175                        cpy->peer_ref = alloc_ref(expn_name);
1176                        free(expn_name);
1177                        if (refspec->force)
1178                                cpy->peer_ref->force = 1;
1179                        *tail = cpy;
1180                        tail = &cpy->next;
1181                }
1182        }
1183
1184        return ret;
1185}
1186
1187static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1188{
1189        const struct ref *ref;
1190        for (ref = refs; ref; ref = ref->next) {
1191                if (refname_match(name, ref->name, ref_fetch_rules))
1192                        return ref;
1193        }
1194        return NULL;
1195}
1196
1197struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1198{
1199        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1200
1201        if (!ref)
1202                return NULL;
1203
1204        return copy_ref(ref);
1205}
1206
1207static struct ref *get_local_ref(const char *name)
1208{
1209        if (!name)
1210                return NULL;
1211
1212        if (!prefixcmp(name, "refs/"))
1213                return alloc_ref(name);
1214
1215        if (!prefixcmp(name, "heads/") ||
1216            !prefixcmp(name, "tags/") ||
1217            !prefixcmp(name, "remotes/"))
1218                return alloc_ref_with_prefix("refs/", 5, name);
1219
1220        return alloc_ref_with_prefix("refs/heads/", 11, name);
1221}
1222
1223int get_fetch_map(const struct ref *remote_refs,
1224                  const struct refspec *refspec,
1225                  struct ref ***tail,
1226                  int missing_ok)
1227{
1228        struct ref *ref_map, **rmp;
1229
1230        if (refspec->pattern) {
1231                ref_map = get_expanded_map(remote_refs, refspec);
1232        } else {
1233                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1234
1235                ref_map = get_remote_ref(remote_refs, name);
1236                if (!missing_ok && !ref_map)
1237                        die("Couldn't find remote ref %s", name);
1238                if (ref_map) {
1239                        ref_map->peer_ref = get_local_ref(refspec->dst);
1240                        if (ref_map->peer_ref && refspec->force)
1241                                ref_map->peer_ref->force = 1;
1242                }
1243        }
1244
1245        for (rmp = &ref_map; *rmp; ) {
1246                if ((*rmp)->peer_ref) {
1247                        int st = check_ref_format((*rmp)->peer_ref->name + 5);
1248                        if (st && st != CHECK_REF_FORMAT_ONELEVEL) {
1249                                struct ref *ignore = *rmp;
1250                                error("* Ignoring funny ref '%s' locally",
1251                                      (*rmp)->peer_ref->name);
1252                                *rmp = (*rmp)->next;
1253                                free(ignore->peer_ref);
1254                                free(ignore);
1255                                continue;
1256                        }
1257                }
1258                rmp = &((*rmp)->next);
1259        }
1260
1261        if (ref_map)
1262                tail_link_ref(ref_map, tail);
1263
1264        return 0;
1265}
1266
1267int resolve_remote_symref(struct ref *ref, struct ref *list)
1268{
1269        if (!ref->symref)
1270                return 0;
1271        for (; list; list = list->next)
1272                if (!strcmp(ref->symref, list->name)) {
1273                        hashcpy(ref->old_sha1, list->old_sha1);
1274                        return 0;
1275                }
1276        return 1;
1277}
1278
1279/*
1280 * Return true if there is anything to report, otherwise false.
1281 */
1282int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
1283{
1284        unsigned char sha1[20];
1285        struct commit *ours, *theirs;
1286        char symmetric[84];
1287        struct rev_info revs;
1288        const char *rev_argv[10], *base;
1289        int rev_argc;
1290
1291        /*
1292         * Nothing to report unless we are marked to build on top of
1293         * somebody else.
1294         */
1295        if (!branch ||
1296            !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
1297                return 0;
1298
1299        /*
1300         * If what we used to build on no longer exists, there is
1301         * nothing to report.
1302         */
1303        base = branch->merge[0]->dst;
1304        if (!resolve_ref(base, sha1, 1, NULL))
1305                return 0;
1306        theirs = lookup_commit(sha1);
1307        if (!theirs)
1308                return 0;
1309
1310        if (!resolve_ref(branch->refname, sha1, 1, NULL))
1311                return 0;
1312        ours = lookup_commit(sha1);
1313        if (!ours)
1314                return 0;
1315
1316        /* are we the same? */
1317        if (theirs == ours)
1318                return 0;
1319
1320        /* Run "rev-list --left-right ours...theirs" internally... */
1321        rev_argc = 0;
1322        rev_argv[rev_argc++] = NULL;
1323        rev_argv[rev_argc++] = "--left-right";
1324        rev_argv[rev_argc++] = symmetric;
1325        rev_argv[rev_argc++] = "--";
1326        rev_argv[rev_argc] = NULL;
1327
1328        strcpy(symmetric, sha1_to_hex(ours->object.sha1));
1329        strcpy(symmetric + 40, "...");
1330        strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
1331
1332        init_revisions(&revs, NULL);
1333        setup_revisions(rev_argc, rev_argv, &revs, NULL);
1334        prepare_revision_walk(&revs);
1335
1336        /* ... and count the commits on each side. */
1337        *num_ours = 0;
1338        *num_theirs = 0;
1339        while (1) {
1340                struct commit *c = get_revision(&revs);
1341                if (!c)
1342                        break;
1343                if (c->object.flags & SYMMETRIC_LEFT)
1344                        (*num_ours)++;
1345                else
1346                        (*num_theirs)++;
1347        }
1348
1349        /* clear object flags smudged by the above traversal */
1350        clear_commit_marks(ours, ALL_REV_FLAGS);
1351        clear_commit_marks(theirs, ALL_REV_FLAGS);
1352        return 1;
1353}
1354
1355/*
1356 * Return true when there is anything to report, otherwise false.
1357 */
1358int format_tracking_info(struct branch *branch, struct strbuf *sb)
1359{
1360        int num_ours, num_theirs;
1361        const char *base;
1362
1363        if (!stat_tracking_info(branch, &num_ours, &num_theirs))
1364                return 0;
1365
1366        base = branch->merge[0]->dst;
1367        if (!prefixcmp(base, "refs/remotes/")) {
1368                base += strlen("refs/remotes/");
1369        }
1370        if (!num_theirs)
1371                strbuf_addf(sb, "Your branch is ahead of '%s' "
1372                            "by %d commit%s.\n",
1373                            base, num_ours, (num_ours == 1) ? "" : "s");
1374        else if (!num_ours)
1375                strbuf_addf(sb, "Your branch is behind '%s' "
1376                            "by %d commit%s, "
1377                            "and can be fast-forwarded.\n",
1378                            base, num_theirs, (num_theirs == 1) ? "" : "s");
1379        else
1380                strbuf_addf(sb, "Your branch and '%s' have diverged,\n"
1381                            "and have %d and %d different commit(s) each, "
1382                            "respectively.\n",
1383                            base, num_ours, num_theirs);
1384        return 1;
1385}