Andrew's git / gitweb.git / remote.c
?
remote.con commit Merge branch 'hm/maint-imap-send-crlf' into maint-1.6.6 (47b333f)
   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#include "tag.h"
   9#include "string-list.h"
  10
  11static struct refspec s_tag_refspec = {
  12        0,
  13        1,
  14        0,
  15        "refs/tags/*",
  16        "refs/tags/*"
  17};
  18
  19const struct refspec *tag_refspec = &s_tag_refspec;
  20
  21struct counted_string {
  22        size_t len;
  23        const char *s;
  24};
  25struct rewrite {
  26        const char *base;
  27        size_t baselen;
  28        struct counted_string *instead_of;
  29        int instead_of_nr;
  30        int instead_of_alloc;
  31};
  32struct rewrites {
  33        struct rewrite **rewrite;
  34        int rewrite_alloc;
  35        int rewrite_nr;
  36};
  37
  38static struct remote **remotes;
  39static int remotes_alloc;
  40static int remotes_nr;
  41
  42static struct branch **branches;
  43static int branches_alloc;
  44static int branches_nr;
  45
  46static struct branch *current_branch;
  47static const char *default_remote_name;
  48static int explicit_default_remote_name;
  49
  50static struct rewrites rewrites;
  51static struct rewrites rewrites_push;
  52
  53#define BUF_SIZE (2048)
  54static char buffer[BUF_SIZE];
  55
  56static const char *alias_url(const char *url, struct rewrites *r)
  57{
  58        int i, j;
  59        char *ret;
  60        struct counted_string *longest;
  61        int longest_i;
  62
  63        longest = NULL;
  64        longest_i = -1;
  65        for (i = 0; i < r->rewrite_nr; i++) {
  66                if (!r->rewrite[i])
  67                        continue;
  68                for (j = 0; j < r->rewrite[i]->instead_of_nr; j++) {
  69                        if (!prefixcmp(url, r->rewrite[i]->instead_of[j].s) &&
  70                            (!longest ||
  71                             longest->len < r->rewrite[i]->instead_of[j].len)) {
  72                                longest = &(r->rewrite[i]->instead_of[j]);
  73                                longest_i = i;
  74                        }
  75                }
  76        }
  77        if (!longest)
  78                return url;
  79
  80        ret = xmalloc(r->rewrite[longest_i]->baselen +
  81                     (strlen(url) - longest->len) + 1);
  82        strcpy(ret, r->rewrite[longest_i]->base);
  83        strcpy(ret + r->rewrite[longest_i]->baselen, url + longest->len);
  84        return ret;
  85}
  86
  87static void add_push_refspec(struct remote *remote, const char *ref)
  88{
  89        ALLOC_GROW(remote->push_refspec,
  90                   remote->push_refspec_nr + 1,
  91                   remote->push_refspec_alloc);
  92        remote->push_refspec[remote->push_refspec_nr++] = ref;
  93}
  94
  95static void add_fetch_refspec(struct remote *remote, const char *ref)
  96{
  97        ALLOC_GROW(remote->fetch_refspec,
  98                   remote->fetch_refspec_nr + 1,
  99                   remote->fetch_refspec_alloc);
 100        remote->fetch_refspec[remote->fetch_refspec_nr++] = ref;
 101}
 102
 103static void add_url(struct remote *remote, const char *url)
 104{
 105        ALLOC_GROW(remote->url, remote->url_nr + 1, remote->url_alloc);
 106        remote->url[remote->url_nr++] = url;
 107}
 108
 109static void add_pushurl(struct remote *remote, const char *pushurl)
 110{
 111        ALLOC_GROW(remote->pushurl, remote->pushurl_nr + 1, remote->pushurl_alloc);
 112        remote->pushurl[remote->pushurl_nr++] = pushurl;
 113}
 114
 115static void add_pushurl_alias(struct remote *remote, const char *url)
 116{
 117        const char *pushurl = alias_url(url, &rewrites_push);
 118        if (pushurl != url)
 119                add_pushurl(remote, pushurl);
 120}
 121
 122static void add_url_alias(struct remote *remote, const char *url)
 123{
 124        add_url(remote, alias_url(url, &rewrites));
 125        add_pushurl_alias(remote, url);
 126}
 127
 128static struct remote *make_remote(const char *name, int len)
 129{
 130        struct remote *ret;
 131        int i;
 132
 133        for (i = 0; i < remotes_nr; i++) {
 134                if (len ? (!strncmp(name, remotes[i]->name, len) &&
 135                           !remotes[i]->name[len]) :
 136                    !strcmp(name, remotes[i]->name))
 137                        return remotes[i];
 138        }
 139
 140        ret = xcalloc(1, sizeof(struct remote));
 141        ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 142        remotes[remotes_nr++] = ret;
 143        if (len)
 144                ret->name = xstrndup(name, len);
 145        else
 146                ret->name = xstrdup(name);
 147        return ret;
 148}
 149
 150static void add_merge(struct branch *branch, const char *name)
 151{
 152        ALLOC_GROW(branch->merge_name, branch->merge_nr + 1,
 153                   branch->merge_alloc);
 154        branch->merge_name[branch->merge_nr++] = name;
 155}
 156
 157static struct branch *make_branch(const char *name, int len)
 158{
 159        struct branch *ret;
 160        int i;
 161        char *refname;
 162
 163        for (i = 0; i < branches_nr; i++) {
 164                if (len ? (!strncmp(name, branches[i]->name, len) &&
 165                           !branches[i]->name[len]) :
 166                    !strcmp(name, branches[i]->name))
 167                        return branches[i];
 168        }
 169
 170        ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 171        ret = xcalloc(1, sizeof(struct branch));
 172        branches[branches_nr++] = ret;
 173        if (len)
 174                ret->name = xstrndup(name, len);
 175        else
 176                ret->name = xstrdup(name);
 177        refname = xmalloc(strlen(name) + strlen("refs/heads/") + 1);
 178        strcpy(refname, "refs/heads/");
 179        strcpy(refname + strlen("refs/heads/"), ret->name);
 180        ret->refname = refname;
 181
 182        return ret;
 183}
 184
 185static struct rewrite *make_rewrite(struct rewrites *r, const char *base, int len)
 186{
 187        struct rewrite *ret;
 188        int i;
 189
 190        for (i = 0; i < r->rewrite_nr; i++) {
 191                if (len
 192                    ? (len == r->rewrite[i]->baselen &&
 193                       !strncmp(base, r->rewrite[i]->base, len))
 194                    : !strcmp(base, r->rewrite[i]->base))
 195                        return r->rewrite[i];
 196        }
 197
 198        ALLOC_GROW(r->rewrite, r->rewrite_nr + 1, r->rewrite_alloc);
 199        ret = xcalloc(1, sizeof(struct rewrite));
 200        r->rewrite[r->rewrite_nr++] = ret;
 201        if (len) {
 202                ret->base = xstrndup(base, len);
 203                ret->baselen = len;
 204        }
 205        else {
 206                ret->base = xstrdup(base);
 207                ret->baselen = strlen(base);
 208        }
 209        return ret;
 210}
 211
 212static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 213{
 214        ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 215        rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 216        rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 217        rewrite->instead_of_nr++;
 218}
 219
 220static void read_remotes_file(struct remote *remote)
 221{
 222        FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
 223
 224        if (!f)
 225                return;
 226        remote->origin = REMOTE_REMOTES;
 227        while (fgets(buffer, BUF_SIZE, f)) {
 228                int value_list;
 229                char *s, *p;
 230
 231                if (!prefixcmp(buffer, "URL:")) {
 232                        value_list = 0;
 233                        s = buffer + 4;
 234                } else if (!prefixcmp(buffer, "Push:")) {
 235                        value_list = 1;
 236                        s = buffer + 5;
 237                } else if (!prefixcmp(buffer, "Pull:")) {
 238                        value_list = 2;
 239                        s = buffer + 5;
 240                } else
 241                        continue;
 242
 243                while (isspace(*s))
 244                        s++;
 245                if (!*s)
 246                        continue;
 247
 248                p = s + strlen(s);
 249                while (isspace(p[-1]))
 250                        *--p = 0;
 251
 252                switch (value_list) {
 253                case 0:
 254                        add_url_alias(remote, xstrdup(s));
 255                        break;
 256                case 1:
 257                        add_push_refspec(remote, xstrdup(s));
 258                        break;
 259                case 2:
 260                        add_fetch_refspec(remote, xstrdup(s));
 261                        break;
 262                }
 263        }
 264        fclose(f);
 265}
 266
 267static void read_branches_file(struct remote *remote)
 268{
 269        const char *slash = strchr(remote->name, '/');
 270        char *frag;
 271        struct strbuf branch = STRBUF_INIT;
 272        int n = slash ? slash - remote->name : 1000;
 273        FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 274        char *s, *p;
 275        int len;
 276
 277        if (!f)
 278                return;
 279        s = fgets(buffer, BUF_SIZE, f);
 280        fclose(f);
 281        if (!s)
 282                return;
 283        while (isspace(*s))
 284                s++;
 285        if (!*s)
 286                return;
 287        remote->origin = REMOTE_BRANCHES;
 288        p = s + strlen(s);
 289        while (isspace(p[-1]))
 290                *--p = 0;
 291        len = p - s;
 292        if (slash)
 293                len += strlen(slash);
 294        p = xmalloc(len + 1);
 295        strcpy(p, s);
 296        if (slash)
 297                strcat(p, slash);
 298
 299        /*
 300         * With "slash", e.g. "git fetch jgarzik/netdev-2.6" when
 301         * reading from $GIT_DIR/branches/jgarzik fetches "HEAD" from
 302         * the partial URL obtained from the branches file plus
 303         * "/netdev-2.6" and does not store it in any tracking ref.
 304         * #branch specifier in the file is ignored.
 305         *
 306         * Otherwise, the branches file would have URL and optionally
 307         * #branch specified.  The "master" (or specified) branch is
 308         * fetched and stored in the local branch of the same name.
 309         */
 310        frag = strchr(p, '#');
 311        if (frag) {
 312                *(frag++) = '\0';
 313                strbuf_addf(&branch, "refs/heads/%s", frag);
 314        } else
 315                strbuf_addstr(&branch, "refs/heads/master");
 316        if (!slash) {
 317                strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 318        } else {
 319                strbuf_reset(&branch);
 320                strbuf_addstr(&branch, "HEAD:");
 321        }
 322        add_url_alias(remote, p);
 323        add_fetch_refspec(remote, strbuf_detach(&branch, NULL));
 324        /*
 325         * Cogito compatible push: push current HEAD to remote #branch
 326         * (master if missing)
 327         */
 328        strbuf_init(&branch, 0);
 329        strbuf_addstr(&branch, "HEAD");
 330        if (frag)
 331                strbuf_addf(&branch, ":refs/heads/%s", frag);
 332        else
 333                strbuf_addstr(&branch, ":refs/heads/master");
 334        add_push_refspec(remote, strbuf_detach(&branch, NULL));
 335        remote->fetch_tags = 1; /* always auto-follow */
 336}
 337
 338static int handle_config(const char *key, const char *value, void *cb)
 339{
 340        const char *name;
 341        const char *subkey;
 342        struct remote *remote;
 343        struct branch *branch;
 344        if (!prefixcmp(key, "branch.")) {
 345                name = key + 7;
 346                subkey = strrchr(name, '.');
 347                if (!subkey)
 348                        return 0;
 349                branch = make_branch(name, subkey - name);
 350                if (!strcmp(subkey, ".remote")) {
 351                        if (!value)
 352                                return config_error_nonbool(key);
 353                        branch->remote_name = xstrdup(value);
 354                        if (branch == current_branch) {
 355                                default_remote_name = branch->remote_name;
 356                                explicit_default_remote_name = 1;
 357                        }
 358                } else if (!strcmp(subkey, ".merge")) {
 359                        if (!value)
 360                                return config_error_nonbool(key);
 361                        add_merge(branch, xstrdup(value));
 362                }
 363                return 0;
 364        }
 365        if (!prefixcmp(key, "url.")) {
 366                struct rewrite *rewrite;
 367                name = key + 4;
 368                subkey = strrchr(name, '.');
 369                if (!subkey)
 370                        return 0;
 371                if (!strcmp(subkey, ".insteadof")) {
 372                        rewrite = make_rewrite(&rewrites, name, subkey - name);
 373                        if (!value)
 374                                return config_error_nonbool(key);
 375                        add_instead_of(rewrite, xstrdup(value));
 376                } else if (!strcmp(subkey, ".pushinsteadof")) {
 377                        rewrite = make_rewrite(&rewrites_push, name, subkey - name);
 378                        if (!value)
 379                                return config_error_nonbool(key);
 380                        add_instead_of(rewrite, xstrdup(value));
 381                }
 382        }
 383        if (prefixcmp(key,  "remote."))
 384                return 0;
 385        name = key + 7;
 386        if (*name == '/') {
 387                warning("Config remote shorthand cannot begin with '/': %s",
 388                        name);
 389                return 0;
 390        }
 391        subkey = strrchr(name, '.');
 392        if (!subkey)
 393                return 0;
 394        remote = make_remote(name, subkey - name);
 395        remote->origin = REMOTE_CONFIG;
 396        if (!strcmp(subkey, ".mirror"))
 397                remote->mirror = git_config_bool(key, value);
 398        else if (!strcmp(subkey, ".skipdefaultupdate"))
 399                remote->skip_default_update = git_config_bool(key, value);
 400        else if (!strcmp(subkey, ".skipfetchall"))
 401                remote->skip_default_update = git_config_bool(key, value);
 402        else if (!strcmp(subkey, ".url")) {
 403                const char *v;
 404                if (git_config_string(&v, key, value))
 405                        return -1;
 406                add_url(remote, v);
 407        } else if (!strcmp(subkey, ".pushurl")) {
 408                const char *v;
 409                if (git_config_string(&v, key, value))
 410                        return -1;
 411                add_pushurl(remote, v);
 412        } else if (!strcmp(subkey, ".push")) {
 413                const char *v;
 414                if (git_config_string(&v, key, value))
 415                        return -1;
 416                add_push_refspec(remote, v);
 417        } else if (!strcmp(subkey, ".fetch")) {
 418                const char *v;
 419                if (git_config_string(&v, key, value))
 420                        return -1;
 421                add_fetch_refspec(remote, v);
 422        } else if (!strcmp(subkey, ".receivepack")) {
 423                const char *v;
 424                if (git_config_string(&v, key, value))
 425                        return -1;
 426                if (!remote->receivepack)
 427                        remote->receivepack = v;
 428                else
 429                        error("more than one receivepack given, using the first");
 430        } else if (!strcmp(subkey, ".uploadpack")) {
 431                const char *v;
 432                if (git_config_string(&v, key, value))
 433                        return -1;
 434                if (!remote->uploadpack)
 435                        remote->uploadpack = v;
 436                else
 437                        error("more than one uploadpack given, using the first");
 438        } else if (!strcmp(subkey, ".tagopt")) {
 439                if (!strcmp(value, "--no-tags"))
 440                        remote->fetch_tags = -1;
 441        } else if (!strcmp(subkey, ".proxy")) {
 442                return git_config_string((const char **)&remote->http_proxy,
 443                                         key, value);
 444        }
 445        return 0;
 446}
 447
 448static void alias_all_urls(void)
 449{
 450        int i, j;
 451        for (i = 0; i < remotes_nr; i++) {
 452                int add_pushurl_aliases;
 453                if (!remotes[i])
 454                        continue;
 455                for (j = 0; j < remotes[i]->pushurl_nr; j++) {
 456                        remotes[i]->pushurl[j] = alias_url(remotes[i]->pushurl[j], &rewrites);
 457                }
 458                add_pushurl_aliases = remotes[i]->pushurl_nr == 0;
 459                for (j = 0; j < remotes[i]->url_nr; j++) {
 460                        if (add_pushurl_aliases)
 461                                add_pushurl_alias(remotes[i], remotes[i]->url[j]);
 462                        remotes[i]->url[j] = alias_url(remotes[i]->url[j], &rewrites);
 463                }
 464        }
 465}
 466
 467static void read_config(void)
 468{
 469        unsigned char sha1[20];
 470        const char *head_ref;
 471        int flag;
 472        if (default_remote_name) // did this already
 473                return;
 474        default_remote_name = xstrdup("origin");
 475        current_branch = NULL;
 476        head_ref = resolve_ref("HEAD", sha1, 0, &flag);
 477        if (head_ref && (flag & REF_ISSYMREF) &&
 478            !prefixcmp(head_ref, "refs/heads/")) {
 479                current_branch =
 480                        make_branch(head_ref + strlen("refs/heads/"), 0);
 481        }
 482        git_config(handle_config, NULL);
 483        alias_all_urls();
 484}
 485
 486/*
 487 * We need to make sure the tracking branches are well formed, but a
 488 * wildcard refspec in "struct refspec" must have a trailing slash. We
 489 * temporarily drop the trailing '/' while calling check_ref_format(),
 490 * and put it back.  The caller knows that a CHECK_REF_FORMAT_ONELEVEL
 491 * error return is Ok for a wildcard refspec.
 492 */
 493static int verify_refname(char *name, int is_glob)
 494{
 495        int result;
 496
 497        result = check_ref_format(name);
 498        if (is_glob && result == CHECK_REF_FORMAT_WILDCARD)
 499                result = CHECK_REF_FORMAT_OK;
 500        return result;
 501}
 502
 503/*
 504 * This function frees a refspec array.
 505 * Warning: code paths should be checked to ensure that the src
 506 *          and dst pointers are always freeable pointers as well
 507 *          as the refspec pointer itself.
 508 */
 509static void free_refspecs(struct refspec *refspec, int nr_refspec)
 510{
 511        int i;
 512
 513        if (!refspec)
 514                return;
 515
 516        for (i = 0; i < nr_refspec; i++) {
 517                free(refspec[i].src);
 518                free(refspec[i].dst);
 519        }
 520        free(refspec);
 521}
 522
 523static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 524{
 525        int i;
 526        int st;
 527        struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 528
 529        for (i = 0; i < nr_refspec; i++) {
 530                size_t llen;
 531                int is_glob;
 532                const char *lhs, *rhs;
 533
 534                is_glob = 0;
 535
 536                lhs = refspec[i];
 537                if (*lhs == '+') {
 538                        rs[i].force = 1;
 539                        lhs++;
 540                }
 541
 542                rhs = strrchr(lhs, ':');
 543
 544                /*
 545                 * Before going on, special case ":" (or "+:") as a refspec
 546                 * for matching refs.
 547                 */
 548                if (!fetch && rhs == lhs && rhs[1] == '\0') {
 549                        rs[i].matching = 1;
 550                        continue;
 551                }
 552
 553                if (rhs) {
 554                        size_t rlen = strlen(++rhs);
 555                        is_glob = (1 <= rlen && strchr(rhs, '*'));
 556                        rs[i].dst = xstrndup(rhs, rlen);
 557                }
 558
 559                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 560                if (1 <= llen && memchr(lhs, '*', llen)) {
 561                        if ((rhs && !is_glob) || (!rhs && fetch))
 562                                goto invalid;
 563                        is_glob = 1;
 564                } else if (rhs && is_glob) {
 565                        goto invalid;
 566                }
 567
 568                rs[i].pattern = is_glob;
 569                rs[i].src = xstrndup(lhs, llen);
 570
 571                if (fetch) {
 572                        /*
 573                         * LHS
 574                         * - empty is allowed; it means HEAD.
 575                         * - otherwise it must be a valid looking ref.
 576                         */
 577                        if (!*rs[i].src)
 578                                ; /* empty is ok */
 579                        else {
 580                                st = verify_refname(rs[i].src, is_glob);
 581                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 582                                        goto invalid;
 583                        }
 584                        /*
 585                         * RHS
 586                         * - missing is ok, and is same as empty.
 587                         * - empty is ok; it means not to store.
 588                         * - otherwise it must be a valid looking ref.
 589                         */
 590                        if (!rs[i].dst) {
 591                                ; /* ok */
 592                        } else if (!*rs[i].dst) {
 593                                ; /* ok */
 594                        } else {
 595                                st = verify_refname(rs[i].dst, is_glob);
 596                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 597                                        goto invalid;
 598                        }
 599                } else {
 600                        /*
 601                         * LHS
 602                         * - empty is allowed; it means delete.
 603                         * - when wildcarded, it must be a valid looking ref.
 604                         * - otherwise, it must be an extended SHA-1, but
 605                         *   there is no existing way to validate this.
 606                         */
 607                        if (!*rs[i].src)
 608                                ; /* empty is ok */
 609                        else if (is_glob) {
 610                                st = verify_refname(rs[i].src, is_glob);
 611                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 612                                        goto invalid;
 613                        }
 614                        else
 615                                ; /* anything goes, for now */
 616                        /*
 617                         * RHS
 618                         * - missing is allowed, but LHS then must be a
 619                         *   valid looking ref.
 620                         * - empty is not allowed.
 621                         * - otherwise it must be a valid looking ref.
 622                         */
 623                        if (!rs[i].dst) {
 624                                st = verify_refname(rs[i].src, is_glob);
 625                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 626                                        goto invalid;
 627                        } else if (!*rs[i].dst) {
 628                                goto invalid;
 629                        } else {
 630                                st = verify_refname(rs[i].dst, is_glob);
 631                                if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 632                                        goto invalid;
 633                        }
 634                }
 635        }
 636        return rs;
 637
 638 invalid:
 639        if (verify) {
 640                /*
 641                 * nr_refspec must be greater than zero and i must be valid
 642                 * since it is only possible to reach this point from within
 643                 * the for loop above.
 644                 */
 645                free_refspecs(rs, i+1);
 646                return NULL;
 647        }
 648        die("Invalid refspec '%s'", refspec[i]);
 649}
 650
 651int valid_fetch_refspec(const char *fetch_refspec_str)
 652{
 653        const char *fetch_refspec[] = { fetch_refspec_str };
 654        struct refspec *refspec;
 655
 656        refspec = parse_refspec_internal(1, fetch_refspec, 1, 1);
 657        free_refspecs(refspec, 1);
 658        return !!refspec;
 659}
 660
 661struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 662{
 663        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 664}
 665
 666static struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 667{
 668        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 669}
 670
 671static int valid_remote_nick(const char *name)
 672{
 673        if (!name[0] || is_dot_or_dotdot(name))
 674                return 0;
 675        return !strchr(name, '/'); /* no slash */
 676}
 677
 678struct remote *remote_get(const char *name)
 679{
 680        struct remote *ret;
 681        int name_given = 0;
 682
 683        read_config();
 684        if (name)
 685                name_given = 1;
 686        else {
 687                name = default_remote_name;
 688                name_given = explicit_default_remote_name;
 689        }
 690
 691        ret = make_remote(name, 0);
 692        if (valid_remote_nick(name)) {
 693                if (!ret->url)
 694                        read_remotes_file(ret);
 695                if (!ret->url)
 696                        read_branches_file(ret);
 697        }
 698        if (name_given && !ret->url)
 699                add_url_alias(ret, name);
 700        if (!ret->url)
 701                return NULL;
 702        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 703        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 704        return ret;
 705}
 706
 707int remote_is_configured(const char *name)
 708{
 709        int i;
 710        read_config();
 711
 712        for (i = 0; i < remotes_nr; i++)
 713                if (!strcmp(name, remotes[i]->name))
 714                        return 1;
 715        return 0;
 716}
 717
 718int for_each_remote(each_remote_fn fn, void *priv)
 719{
 720        int i, result = 0;
 721        read_config();
 722        for (i = 0; i < remotes_nr && !result; i++) {
 723                struct remote *r = remotes[i];
 724                if (!r)
 725                        continue;
 726                if (!r->fetch)
 727                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 728                                                       r->fetch_refspec);
 729                if (!r->push)
 730                        r->push = parse_push_refspec(r->push_refspec_nr,
 731                                                     r->push_refspec);
 732                result = fn(r, priv);
 733        }
 734        return result;
 735}
 736
 737void ref_remove_duplicates(struct ref *ref_map)
 738{
 739        struct string_list refs = { NULL, 0, 0, 0 };
 740        struct string_list_item *item = NULL;
 741        struct ref *prev = NULL, *next = NULL;
 742        for (; ref_map; prev = ref_map, ref_map = next) {
 743                next = ref_map->next;
 744                if (!ref_map->peer_ref)
 745                        continue;
 746
 747                item = string_list_lookup(ref_map->peer_ref->name, &refs);
 748                if (item) {
 749                        if (strcmp(((struct ref *)item->util)->name,
 750                                   ref_map->name))
 751                                die("%s tracks both %s and %s",
 752                                    ref_map->peer_ref->name,
 753                                    ((struct ref *)item->util)->name,
 754                                    ref_map->name);
 755                        prev->next = ref_map->next;
 756                        free(ref_map->peer_ref);
 757                        free(ref_map);
 758                        ref_map = prev; /* skip this; we freed it */
 759                        continue;
 760                }
 761
 762                item = string_list_insert(ref_map->peer_ref->name, &refs);
 763                item->util = ref_map;
 764        }
 765        string_list_clear(&refs, 0);
 766}
 767
 768int remote_has_url(struct remote *remote, const char *url)
 769{
 770        int i;
 771        for (i = 0; i < remote->url_nr; i++) {
 772                if (!strcmp(remote->url[i], url))
 773                        return 1;
 774        }
 775        return 0;
 776}
 777
 778static int match_name_with_pattern(const char *key, const char *name,
 779                                   const char *value, char **result)
 780{
 781        const char *kstar = strchr(key, '*');
 782        size_t klen;
 783        size_t ksuffixlen;
 784        size_t namelen;
 785        int ret;
 786        if (!kstar)
 787                die("Key '%s' of pattern had no '*'", key);
 788        klen = kstar - key;
 789        ksuffixlen = strlen(kstar + 1);
 790        namelen = strlen(name);
 791        ret = !strncmp(name, key, klen) && namelen >= klen + ksuffixlen &&
 792                !memcmp(name + namelen - ksuffixlen, kstar + 1, ksuffixlen);
 793        if (ret && value) {
 794                const char *vstar = strchr(value, '*');
 795                size_t vlen;
 796                size_t vsuffixlen;
 797                if (!vstar)
 798                        die("Value '%s' of pattern has no '*'", value);
 799                vlen = vstar - value;
 800                vsuffixlen = strlen(vstar + 1);
 801                *result = xmalloc(vlen + vsuffixlen +
 802                                  strlen(name) -
 803                                  klen - ksuffixlen + 1);
 804                strncpy(*result, value, vlen);
 805                strncpy(*result + vlen,
 806                        name + klen, namelen - klen - ksuffixlen);
 807                strcpy(*result + vlen + namelen - klen - ksuffixlen,
 808                       vstar + 1);
 809        }
 810        return ret;
 811}
 812
 813int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 814{
 815        int find_src = refspec->src == NULL;
 816        char *needle, **result;
 817        int i;
 818
 819        if (find_src) {
 820                if (!refspec->dst)
 821                        return error("find_tracking: need either src or dst");
 822                needle = refspec->dst;
 823                result = &refspec->src;
 824        } else {
 825                needle = refspec->src;
 826                result = &refspec->dst;
 827        }
 828
 829        for (i = 0; i < remote->fetch_refspec_nr; i++) {
 830                struct refspec *fetch = &remote->fetch[i];
 831                const char *key = find_src ? fetch->dst : fetch->src;
 832                const char *value = find_src ? fetch->src : fetch->dst;
 833                if (!fetch->dst)
 834                        continue;
 835                if (fetch->pattern) {
 836                        if (match_name_with_pattern(key, needle, value, result)) {
 837                                refspec->force = fetch->force;
 838                                return 0;
 839                        }
 840                } else if (!strcmp(needle, key)) {
 841                        *result = xstrdup(value);
 842                        refspec->force = fetch->force;
 843                        return 0;
 844                }
 845        }
 846        return -1;
 847}
 848
 849static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 850                const char *name)
 851{
 852        size_t len = strlen(name);
 853        struct ref *ref = xcalloc(1, sizeof(struct ref) + prefixlen + len + 1);
 854        memcpy(ref->name, prefix, prefixlen);
 855        memcpy(ref->name + prefixlen, name, len);
 856        return ref;
 857}
 858
 859struct ref *alloc_ref(const char *name)
 860{
 861        return alloc_ref_with_prefix("", 0, name);
 862}
 863
 864static struct ref *copy_ref(const struct ref *ref)
 865{
 866        struct ref *cpy;
 867        size_t len;
 868        if (!ref)
 869                return NULL;
 870        len = strlen(ref->name);
 871        cpy = xmalloc(sizeof(struct ref) + len + 1);
 872        memcpy(cpy, ref, sizeof(struct ref) + len + 1);
 873        cpy->next = NULL;
 874        cpy->symref = ref->symref ? xstrdup(ref->symref) : NULL;
 875        cpy->remote_status = ref->remote_status ? xstrdup(ref->remote_status) : NULL;
 876        cpy->peer_ref = copy_ref(ref->peer_ref);
 877        return cpy;
 878}
 879
 880struct ref *copy_ref_list(const struct ref *ref)
 881{
 882        struct ref *ret = NULL;
 883        struct ref **tail = &ret;
 884        while (ref) {
 885                *tail = copy_ref(ref);
 886                ref = ref->next;
 887                tail = &((*tail)->next);
 888        }
 889        return ret;
 890}
 891
 892static void free_ref(struct ref *ref)
 893{
 894        if (!ref)
 895                return;
 896        free_ref(ref->peer_ref);
 897        free(ref->remote_status);
 898        free(ref->symref);
 899        free(ref);
 900}
 901
 902void free_refs(struct ref *ref)
 903{
 904        struct ref *next;
 905        while (ref) {
 906                next = ref->next;
 907                free_ref(ref);
 908                ref = next;
 909        }
 910}
 911
 912static int count_refspec_match(const char *pattern,
 913                               struct ref *refs,
 914                               struct ref **matched_ref)
 915{
 916        int patlen = strlen(pattern);
 917        struct ref *matched_weak = NULL;
 918        struct ref *matched = NULL;
 919        int weak_match = 0;
 920        int match = 0;
 921
 922        for (weak_match = match = 0; refs; refs = refs->next) {
 923                char *name = refs->name;
 924                int namelen = strlen(name);
 925
 926                if (!refname_match(pattern, name, ref_rev_parse_rules))
 927                        continue;
 928
 929                /* A match is "weak" if it is with refs outside
 930                 * heads or tags, and did not specify the pattern
 931                 * in full (e.g. "refs/remotes/origin/master") or at
 932                 * least from the toplevel (e.g. "remotes/origin/master");
 933                 * otherwise "git push $URL master" would result in
 934                 * ambiguity between remotes/origin/master and heads/master
 935                 * at the remote site.
 936                 */
 937                if (namelen != patlen &&
 938                    patlen != namelen - 5 &&
 939                    prefixcmp(name, "refs/heads/") &&
 940                    prefixcmp(name, "refs/tags/")) {
 941                        /* We want to catch the case where only weak
 942                         * matches are found and there are multiple
 943                         * matches, and where more than one strong
 944                         * matches are found, as ambiguous.  One
 945                         * strong match with zero or more weak matches
 946                         * are acceptable as a unique match.
 947                         */
 948                        matched_weak = refs;
 949                        weak_match++;
 950                }
 951                else {
 952                        matched = refs;
 953                        match++;
 954                }
 955        }
 956        if (!matched) {
 957                *matched_ref = matched_weak;
 958                return weak_match;
 959        }
 960        else {
 961                *matched_ref = matched;
 962                return match;
 963        }
 964}
 965
 966static void tail_link_ref(struct ref *ref, struct ref ***tail)
 967{
 968        **tail = ref;
 969        while (ref->next)
 970                ref = ref->next;
 971        *tail = &ref->next;
 972}
 973
 974static struct ref *try_explicit_object_name(const char *name)
 975{
 976        unsigned char sha1[20];
 977        struct ref *ref;
 978
 979        if (!*name) {
 980                ref = alloc_ref("(delete)");
 981                hashclr(ref->new_sha1);
 982                return ref;
 983        }
 984        if (get_sha1(name, sha1))
 985                return NULL;
 986        ref = alloc_ref(name);
 987        hashcpy(ref->new_sha1, sha1);
 988        return ref;
 989}
 990
 991static struct ref *make_linked_ref(const char *name, struct ref ***tail)
 992{
 993        struct ref *ret = alloc_ref(name);
 994        tail_link_ref(ret, tail);
 995        return ret;
 996}
 997
 998static char *guess_ref(const char *name, struct ref *peer)
 999{
1000        struct strbuf buf = STRBUF_INIT;
1001        unsigned char sha1[20];
1002
1003        const char *r = resolve_ref(peer->name, sha1, 1, NULL);
1004        if (!r)
1005                return NULL;
1006
1007        if (!prefixcmp(r, "refs/heads/"))
1008                strbuf_addstr(&buf, "refs/heads/");
1009        else if (!prefixcmp(r, "refs/tags/"))
1010                strbuf_addstr(&buf, "refs/tags/");
1011        else
1012                return NULL;
1013
1014        strbuf_addstr(&buf, name);
1015        return strbuf_detach(&buf, NULL);
1016}
1017
1018static int match_explicit(struct ref *src, struct ref *dst,
1019                          struct ref ***dst_tail,
1020                          struct refspec *rs)
1021{
1022        struct ref *matched_src, *matched_dst;
1023        int copy_src;
1024
1025        const char *dst_value = rs->dst;
1026        char *dst_guess;
1027
1028        if (rs->pattern || rs->matching)
1029                return 0;
1030
1031        matched_src = matched_dst = NULL;
1032        switch (count_refspec_match(rs->src, src, &matched_src)) {
1033        case 1:
1034                copy_src = 1;
1035                break;
1036        case 0:
1037                /* The source could be in the get_sha1() format
1038                 * not a reference name.  :refs/other is a
1039                 * way to delete 'other' ref at the remote end.
1040                 */
1041                matched_src = try_explicit_object_name(rs->src);
1042                if (!matched_src)
1043                        return error("src refspec %s does not match any.", rs->src);
1044                copy_src = 0;
1045                break;
1046        default:
1047                return error("src refspec %s matches more than one.", rs->src);
1048        }
1049
1050        if (!dst_value) {
1051                unsigned char sha1[20];
1052                int flag;
1053
1054                dst_value = resolve_ref(matched_src->name, sha1, 1, &flag);
1055                if (!dst_value ||
1056                    ((flag & REF_ISSYMREF) &&
1057                     prefixcmp(dst_value, "refs/heads/")))
1058                        die("%s cannot be resolved to branch.",
1059                            matched_src->name);
1060        }
1061
1062        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
1063        case 1:
1064                break;
1065        case 0:
1066                if (!memcmp(dst_value, "refs/", 5))
1067                        matched_dst = make_linked_ref(dst_value, dst_tail);
1068                else if ((dst_guess = guess_ref(dst_value, matched_src)))
1069                        matched_dst = make_linked_ref(dst_guess, dst_tail);
1070                else
1071                        error("unable to push to unqualified destination: %s\n"
1072                              "The destination refspec neither matches an "
1073                              "existing ref on the remote nor\n"
1074                              "begins with refs/, and we are unable to "
1075                              "guess a prefix based on the source ref.",
1076                              dst_value);
1077                break;
1078        default:
1079                matched_dst = NULL;
1080                error("dst refspec %s matches more than one.",
1081                      dst_value);
1082                break;
1083        }
1084        if (!matched_dst)
1085                return -1;
1086        if (matched_dst->peer_ref)
1087                return error("dst ref %s receives from more than one src.",
1088                      matched_dst->name);
1089        else {
1090                matched_dst->peer_ref = copy_src ? copy_ref(matched_src) : matched_src;
1091                matched_dst->force = rs->force;
1092        }
1093        return 0;
1094}
1095
1096static int match_explicit_refs(struct ref *src, struct ref *dst,
1097                               struct ref ***dst_tail, struct refspec *rs,
1098                               int rs_nr)
1099{
1100        int i, errs;
1101        for (i = errs = 0; i < rs_nr; i++)
1102                errs += match_explicit(src, dst, dst_tail, &rs[i]);
1103        return errs;
1104}
1105
1106static const struct refspec *check_pattern_match(const struct refspec *rs,
1107                                                 int rs_nr,
1108                                                 const struct ref *src)
1109{
1110        int i;
1111        int matching_refs = -1;
1112        for (i = 0; i < rs_nr; i++) {
1113                if (rs[i].matching &&
1114                    (matching_refs == -1 || rs[i].force)) {
1115                        matching_refs = i;
1116                        continue;
1117                }
1118
1119                if (rs[i].pattern && match_name_with_pattern(rs[i].src, src->name,
1120                                                             NULL, NULL))
1121                        return rs + i;
1122        }
1123        if (matching_refs != -1)
1124                return rs + matching_refs;
1125        else
1126                return NULL;
1127}
1128
1129static struct ref **tail_ref(struct ref **head)
1130{
1131        struct ref **tail = head;
1132        while (*tail)
1133                tail = &((*tail)->next);
1134        return tail;
1135}
1136
1137/*
1138 * Note. This is used only by "push"; refspec matching rules for
1139 * push and fetch are subtly different, so do not try to reuse it
1140 * without thinking.
1141 */
1142int match_refs(struct ref *src, struct ref **dst,
1143               int nr_refspec, const char **refspec, int flags)
1144{
1145        struct refspec *rs;
1146        int send_all = flags & MATCH_REFS_ALL;
1147        int send_mirror = flags & MATCH_REFS_MIRROR;
1148        int errs;
1149        static const char *default_refspec[] = { ":", NULL };
1150        struct ref **dst_tail = tail_ref(dst);
1151
1152        if (!nr_refspec) {
1153                nr_refspec = 1;
1154                refspec = default_refspec;
1155        }
1156        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1157        errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
1158
1159        /* pick the remainder */
1160        for ( ; src; src = src->next) {
1161                struct ref *dst_peer;
1162                const struct refspec *pat = NULL;
1163                char *dst_name;
1164                if (src->peer_ref)
1165                        continue;
1166
1167                pat = check_pattern_match(rs, nr_refspec, src);
1168                if (!pat)
1169                        continue;
1170
1171                if (pat->matching) {
1172                        /*
1173                         * "matching refs"; traditionally we pushed everything
1174                         * including refs outside refs/heads/ hierarchy, but
1175                         * that does not make much sense these days.
1176                         */
1177                        if (!send_mirror && prefixcmp(src->name, "refs/heads/"))
1178                                continue;
1179                        dst_name = xstrdup(src->name);
1180
1181                } else {
1182                        const char *dst_side = pat->dst ? pat->dst : pat->src;
1183                        if (!match_name_with_pattern(pat->src, src->name,
1184                                                     dst_side, &dst_name))
1185                                die("Didn't think it matches any more");
1186                }
1187                dst_peer = find_ref_by_name(*dst, dst_name);
1188                if (dst_peer) {
1189                        if (dst_peer->peer_ref)
1190                                /* We're already sending something to this ref. */
1191                                goto free_name;
1192
1193                } else {
1194                        if (pat->matching && !(send_all || send_mirror))
1195                                /*
1196                                 * Remote doesn't have it, and we have no
1197                                 * explicit pattern, and we don't have
1198                                 * --all nor --mirror.
1199                                 */
1200                                goto free_name;
1201
1202                        /* Create a new one and link it */
1203                        dst_peer = make_linked_ref(dst_name, &dst_tail);
1204                        hashcpy(dst_peer->new_sha1, src->new_sha1);
1205                }
1206                dst_peer->peer_ref = copy_ref(src);
1207                dst_peer->force = pat->force;
1208        free_name:
1209                free(dst_name);
1210        }
1211        if (errs)
1212                return -1;
1213        return 0;
1214}
1215
1216struct branch *branch_get(const char *name)
1217{
1218        struct branch *ret;
1219
1220        read_config();
1221        if (!name || !*name || !strcmp(name, "HEAD"))
1222                ret = current_branch;
1223        else
1224                ret = make_branch(name, 0);
1225        if (ret && ret->remote_name) {
1226                ret->remote = remote_get(ret->remote_name);
1227                if (ret->merge_nr) {
1228                        int i;
1229                        ret->merge = xcalloc(sizeof(*ret->merge),
1230                                             ret->merge_nr);
1231                        for (i = 0; i < ret->merge_nr; i++) {
1232                                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1233                                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1234                                if (remote_find_tracking(ret->remote, ret->merge[i])
1235                                    && !strcmp(ret->remote_name, "."))
1236                                        ret->merge[i]->dst = xstrdup(ret->merge_name[i]);
1237                        }
1238                }
1239        }
1240        return ret;
1241}
1242
1243int branch_has_merge_config(struct branch *branch)
1244{
1245        return branch && !!branch->merge;
1246}
1247
1248int branch_merge_matches(struct branch *branch,
1249                                 int i,
1250                                 const char *refname)
1251{
1252        if (!branch || i < 0 || i >= branch->merge_nr)
1253                return 0;
1254        return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
1255}
1256
1257static struct ref *get_expanded_map(const struct ref *remote_refs,
1258                                    const struct refspec *refspec)
1259{
1260        const struct ref *ref;
1261        struct ref *ret = NULL;
1262        struct ref **tail = &ret;
1263
1264        char *expn_name;
1265
1266        for (ref = remote_refs; ref; ref = ref->next) {
1267                if (strchr(ref->name, '^'))
1268                        continue; /* a dereference item */
1269                if (match_name_with_pattern(refspec->src, ref->name,
1270                                            refspec->dst, &expn_name)) {
1271                        struct ref *cpy = copy_ref(ref);
1272
1273                        cpy->peer_ref = alloc_ref(expn_name);
1274                        free(expn_name);
1275                        if (refspec->force)
1276                                cpy->peer_ref->force = 1;
1277                        *tail = cpy;
1278                        tail = &cpy->next;
1279                }
1280        }
1281
1282        return ret;
1283}
1284
1285static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1286{
1287        const struct ref *ref;
1288        for (ref = refs; ref; ref = ref->next) {
1289                if (refname_match(name, ref->name, ref_fetch_rules))
1290                        return ref;
1291        }
1292        return NULL;
1293}
1294
1295struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1296{
1297        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1298
1299        if (!ref)
1300                return NULL;
1301
1302        return copy_ref(ref);
1303}
1304
1305static struct ref *get_local_ref(const char *name)
1306{
1307        if (!name || name[0] == '\0')
1308                return NULL;
1309
1310        if (!prefixcmp(name, "refs/"))
1311                return alloc_ref(name);
1312
1313        if (!prefixcmp(name, "heads/") ||
1314            !prefixcmp(name, "tags/") ||
1315            !prefixcmp(name, "remotes/"))
1316                return alloc_ref_with_prefix("refs/", 5, name);
1317
1318        return alloc_ref_with_prefix("refs/heads/", 11, name);
1319}
1320
1321int get_fetch_map(const struct ref *remote_refs,
1322                  const struct refspec *refspec,
1323                  struct ref ***tail,
1324                  int missing_ok)
1325{
1326        struct ref *ref_map, **rmp;
1327
1328        if (refspec->pattern) {
1329                ref_map = get_expanded_map(remote_refs, refspec);
1330        } else {
1331                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1332
1333                ref_map = get_remote_ref(remote_refs, name);
1334                if (!missing_ok && !ref_map)
1335                        die("Couldn't find remote ref %s", name);
1336                if (ref_map) {
1337                        ref_map->peer_ref = get_local_ref(refspec->dst);
1338                        if (ref_map->peer_ref && refspec->force)
1339                                ref_map->peer_ref->force = 1;
1340                }
1341        }
1342
1343        for (rmp = &ref_map; *rmp; ) {
1344                if ((*rmp)->peer_ref) {
1345                        int st = check_ref_format((*rmp)->peer_ref->name + 5);
1346                        if (st && st != CHECK_REF_FORMAT_ONELEVEL) {
1347                                struct ref *ignore = *rmp;
1348                                error("* Ignoring funny ref '%s' locally",
1349                                      (*rmp)->peer_ref->name);
1350                                *rmp = (*rmp)->next;
1351                                free(ignore->peer_ref);
1352                                free(ignore);
1353                                continue;
1354                        }
1355                }
1356                rmp = &((*rmp)->next);
1357        }
1358
1359        if (ref_map)
1360                tail_link_ref(ref_map, tail);
1361
1362        return 0;
1363}
1364
1365int resolve_remote_symref(struct ref *ref, struct ref *list)
1366{
1367        if (!ref->symref)
1368                return 0;
1369        for (; list; list = list->next)
1370                if (!strcmp(ref->symref, list->name)) {
1371                        hashcpy(ref->old_sha1, list->old_sha1);
1372                        return 0;
1373                }
1374        return 1;
1375}
1376
1377static void unmark_and_free(struct commit_list *list, unsigned int mark)
1378{
1379        while (list) {
1380                struct commit_list *temp = list;
1381                temp->item->object.flags &= ~mark;
1382                list = temp->next;
1383                free(temp);
1384        }
1385}
1386
1387int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
1388{
1389        struct object *o;
1390        struct commit *old, *new;
1391        struct commit_list *list, *used;
1392        int found = 0;
1393
1394        /* Both new and old must be commit-ish and new is descendant of
1395         * old.  Otherwise we require --force.
1396         */
1397        o = deref_tag(parse_object(old_sha1), NULL, 0);
1398        if (!o || o->type != OBJ_COMMIT)
1399                return 0;
1400        old = (struct commit *) o;
1401
1402        o = deref_tag(parse_object(new_sha1), NULL, 0);
1403        if (!o || o->type != OBJ_COMMIT)
1404                return 0;
1405        new = (struct commit *) o;
1406
1407        if (parse_commit(new) < 0)
1408                return 0;
1409
1410        used = list = NULL;
1411        commit_list_insert(new, &list);
1412        while (list) {
1413                new = pop_most_recent_commit(&list, TMP_MARK);
1414                commit_list_insert(new, &used);
1415                if (new == old) {
1416                        found = 1;
1417                        break;
1418                }
1419        }
1420        unmark_and_free(list, TMP_MARK);
1421        unmark_and_free(used, TMP_MARK);
1422        return found;
1423}
1424
1425/*
1426 * Return true if there is anything to report, otherwise false.
1427 */
1428int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
1429{
1430        unsigned char sha1[20];
1431        struct commit *ours, *theirs;
1432        char symmetric[84];
1433        struct rev_info revs;
1434        const char *rev_argv[10], *base;
1435        int rev_argc;
1436
1437        /*
1438         * Nothing to report unless we are marked to build on top of
1439         * somebody else.
1440         */
1441        if (!branch ||
1442            !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
1443                return 0;
1444
1445        /*
1446         * If what we used to build on no longer exists, there is
1447         * nothing to report.
1448         */
1449        base = branch->merge[0]->dst;
1450        if (!resolve_ref(base, sha1, 1, NULL))
1451                return 0;
1452        theirs = lookup_commit_reference(sha1);
1453        if (!theirs)
1454                return 0;
1455
1456        if (!resolve_ref(branch->refname, sha1, 1, NULL))
1457                return 0;
1458        ours = lookup_commit_reference(sha1);
1459        if (!ours)
1460                return 0;
1461
1462        /* are we the same? */
1463        if (theirs == ours)
1464                return 0;
1465
1466        /* Run "rev-list --left-right ours...theirs" internally... */
1467        rev_argc = 0;
1468        rev_argv[rev_argc++] = NULL;
1469        rev_argv[rev_argc++] = "--left-right";
1470        rev_argv[rev_argc++] = symmetric;
1471        rev_argv[rev_argc++] = "--";
1472        rev_argv[rev_argc] = NULL;
1473
1474        strcpy(symmetric, sha1_to_hex(ours->object.sha1));
1475        strcpy(symmetric + 40, "...");
1476        strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
1477
1478        init_revisions(&revs, NULL);
1479        setup_revisions(rev_argc, rev_argv, &revs, NULL);
1480        prepare_revision_walk(&revs);
1481
1482        /* ... and count the commits on each side. */
1483        *num_ours = 0;
1484        *num_theirs = 0;
1485        while (1) {
1486                struct commit *c = get_revision(&revs);
1487                if (!c)
1488                        break;
1489                if (c->object.flags & SYMMETRIC_LEFT)
1490                        (*num_ours)++;
1491                else
1492                        (*num_theirs)++;
1493        }
1494
1495        /* clear object flags smudged by the above traversal */
1496        clear_commit_marks(ours, ALL_REV_FLAGS);
1497        clear_commit_marks(theirs, ALL_REV_FLAGS);
1498        return 1;
1499}
1500
1501/*
1502 * Return true when there is anything to report, otherwise false.
1503 */
1504int format_tracking_info(struct branch *branch, struct strbuf *sb)
1505{
1506        int num_ours, num_theirs;
1507        const char *base;
1508
1509        if (!stat_tracking_info(branch, &num_ours, &num_theirs))
1510                return 0;
1511
1512        base = branch->merge[0]->dst;
1513        base = shorten_unambiguous_ref(base, 0);
1514        if (!num_theirs)
1515                strbuf_addf(sb, "Your branch is ahead of '%s' "
1516                            "by %d commit%s.\n",
1517                            base, num_ours, (num_ours == 1) ? "" : "s");
1518        else if (!num_ours)
1519                strbuf_addf(sb, "Your branch is behind '%s' "
1520                            "by %d commit%s, "
1521                            "and can be fast-forwarded.\n",
1522                            base, num_theirs, (num_theirs == 1) ? "" : "s");
1523        else
1524                strbuf_addf(sb, "Your branch and '%s' have diverged,\n"
1525                            "and have %d and %d different commit(s) each, "
1526                            "respectively.\n",
1527                            base, num_ours, num_theirs);
1528        return 1;
1529}
1530
1531static int one_local_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
1532{
1533        struct ref ***local_tail = cb_data;
1534        struct ref *ref;
1535        int len;
1536
1537        /* we already know it starts with refs/ to get here */
1538        if (check_ref_format(refname + 5))
1539                return 0;
1540
1541        len = strlen(refname) + 1;
1542        ref = xcalloc(1, sizeof(*ref) + len);
1543        hashcpy(ref->new_sha1, sha1);
1544        memcpy(ref->name, refname, len);
1545        **local_tail = ref;
1546        *local_tail = &ref->next;
1547        return 0;
1548}
1549
1550struct ref *get_local_heads(void)
1551{
1552        struct ref *local_refs = NULL, **local_tail = &local_refs;
1553        for_each_ref(one_local_ref, &local_tail);
1554        return local_refs;
1555}
1556
1557struct ref *guess_remote_head(const struct ref *head,
1558                              const struct ref *refs,
1559                              int all)
1560{
1561        const struct ref *r;
1562        struct ref *list = NULL;
1563        struct ref **tail = &list;
1564
1565        if (!head)
1566                return NULL;
1567
1568        /*
1569         * Some transports support directly peeking at
1570         * where HEAD points; if that is the case, then
1571         * we don't have to guess.
1572         */
1573        if (head->symref)
1574                return copy_ref(find_ref_by_name(refs, head->symref));
1575
1576        /* If refs/heads/master could be right, it is. */
1577        if (!all) {
1578                r = find_ref_by_name(refs, "refs/heads/master");
1579                if (r && !hashcmp(r->old_sha1, head->old_sha1))
1580                        return copy_ref(r);
1581        }
1582
1583        /* Look for another ref that points there */
1584        for (r = refs; r; r = r->next) {
1585                if (r != head && !hashcmp(r->old_sha1, head->old_sha1)) {
1586                        *tail = copy_ref(r);
1587                        tail = &((*tail)->next);
1588                        if (!all)
1589                                break;
1590                }
1591        }
1592
1593        return list;
1594}
1595
1596struct stale_heads_info {
1597        struct remote *remote;
1598        struct string_list *ref_names;
1599        struct ref **stale_refs_tail;
1600};
1601
1602static int get_stale_heads_cb(const char *refname,
1603        const unsigned char *sha1, int flags, void *cb_data)
1604{
1605        struct stale_heads_info *info = cb_data;
1606        struct refspec refspec;
1607        memset(&refspec, 0, sizeof(refspec));
1608        refspec.dst = (char *)refname;
1609        if (!remote_find_tracking(info->remote, &refspec)) {
1610                if (!((flags & REF_ISSYMREF) ||
1611                    string_list_has_string(info->ref_names, refspec.src))) {
1612                        struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
1613                        hashcpy(ref->new_sha1, sha1);
1614                }
1615        }
1616        return 0;
1617}
1618
1619struct ref *get_stale_heads(struct remote *remote, struct ref *fetch_map)
1620{
1621        struct ref *ref, *stale_refs = NULL;
1622        struct string_list ref_names = { NULL, 0, 0, 0 };
1623        struct stale_heads_info info;
1624        info.remote = remote;
1625        info.ref_names = &ref_names;
1626        info.stale_refs_tail = &stale_refs;
1627        for (ref = fetch_map; ref; ref = ref->next)
1628                string_list_append(ref->name, &ref_names);
1629        sort_string_list(&ref_names);
1630        for_each_ref(get_stale_heads_cb, &info);
1631        string_list_clear(&ref_names, 0);
1632        return stale_refs;
1633}