remote.con commit Merge branch 'ab/mediawiki-name-truncation' (fcaba62)
   1#include "cache.h"
   2#include "config.h"
   3#include "remote.h"
   4#include "refs.h"
   5#include "commit.h"
   6#include "diff.h"
   7#include "revision.h"
   8#include "dir.h"
   9#include "tag.h"
  10#include "string-list.h"
  11#include "mergesort.h"
  12#include "argv-array.h"
  13
  14enum map_direction { FROM_SRC, FROM_DST };
  15
  16static struct refspec s_tag_refspec = {
  17        0,
  18        1,
  19        0,
  20        0,
  21        "refs/tags/*",
  22        "refs/tags/*"
  23};
  24
  25const struct refspec *tag_refspec = &s_tag_refspec;
  26
  27struct counted_string {
  28        size_t len;
  29        const char *s;
  30};
  31struct rewrite {
  32        const char *base;
  33        size_t baselen;
  34        struct counted_string *instead_of;
  35        int instead_of_nr;
  36        int instead_of_alloc;
  37};
  38struct rewrites {
  39        struct rewrite **rewrite;
  40        int rewrite_alloc;
  41        int rewrite_nr;
  42};
  43
  44static struct remote **remotes;
  45static int remotes_alloc;
  46static int remotes_nr;
  47static struct hashmap remotes_hash;
  48
  49static struct branch **branches;
  50static int branches_alloc;
  51static int branches_nr;
  52
  53static struct branch *current_branch;
  54static const char *pushremote_name;
  55
  56static struct rewrites rewrites;
  57static struct rewrites rewrites_push;
  58
  59static int valid_remote(const struct remote *remote)
  60{
  61        return (!!remote->url) || (!!remote->foreign_vcs);
  62}
  63
  64static const char *alias_url(const char *url, struct rewrites *r)
  65{
  66        int i, j;
  67        struct counted_string *longest;
  68        int longest_i;
  69
  70        longest = NULL;
  71        longest_i = -1;
  72        for (i = 0; i < r->rewrite_nr; i++) {
  73                if (!r->rewrite[i])
  74                        continue;
  75                for (j = 0; j < r->rewrite[i]->instead_of_nr; j++) {
  76                        if (starts_with(url, r->rewrite[i]->instead_of[j].s) &&
  77                            (!longest ||
  78                             longest->len < r->rewrite[i]->instead_of[j].len)) {
  79                                longest = &(r->rewrite[i]->instead_of[j]);
  80                                longest_i = i;
  81                        }
  82                }
  83        }
  84        if (!longest)
  85                return url;
  86
  87        return xstrfmt("%s%s", r->rewrite[longest_i]->base, url + longest->len);
  88}
  89
  90static void add_push_refspec(struct remote *remote, const char *ref)
  91{
  92        ALLOC_GROW(remote->push_refspec,
  93                   remote->push_refspec_nr + 1,
  94                   remote->push_refspec_alloc);
  95        remote->push_refspec[remote->push_refspec_nr++] = ref;
  96}
  97
  98static void add_fetch_refspec(struct remote *remote, const char *ref)
  99{
 100        ALLOC_GROW(remote->fetch_refspec,
 101                   remote->fetch_refspec_nr + 1,
 102                   remote->fetch_refspec_alloc);
 103        remote->fetch_refspec[remote->fetch_refspec_nr++] = ref;
 104}
 105
 106static void add_url(struct remote *remote, const char *url)
 107{
 108        ALLOC_GROW(remote->url, remote->url_nr + 1, remote->url_alloc);
 109        remote->url[remote->url_nr++] = url;
 110}
 111
 112static void add_pushurl(struct remote *remote, const char *pushurl)
 113{
 114        ALLOC_GROW(remote->pushurl, remote->pushurl_nr + 1, remote->pushurl_alloc);
 115        remote->pushurl[remote->pushurl_nr++] = pushurl;
 116}
 117
 118static void add_pushurl_alias(struct remote *remote, const char *url)
 119{
 120        const char *pushurl = alias_url(url, &rewrites_push);
 121        if (pushurl != url)
 122                add_pushurl(remote, pushurl);
 123}
 124
 125static void add_url_alias(struct remote *remote, const char *url)
 126{
 127        add_url(remote, alias_url(url, &rewrites));
 128        add_pushurl_alias(remote, url);
 129}
 130
 131struct remotes_hash_key {
 132        const char *str;
 133        int len;
 134};
 135
 136static int remotes_hash_cmp(const void *unused_cmp_data,
 137                            const void *entry,
 138                            const void *entry_or_key,
 139                            const void *keydata)
 140{
 141        const struct remote *a = entry;
 142        const struct remote *b = entry_or_key;
 143        const struct remotes_hash_key *key = keydata;
 144
 145        if (key)
 146                return strncmp(a->name, key->str, key->len) || a->name[key->len];
 147        else
 148                return strcmp(a->name, b->name);
 149}
 150
 151static inline void init_remotes_hash(void)
 152{
 153        if (!remotes_hash.cmpfn)
 154                hashmap_init(&remotes_hash, remotes_hash_cmp, NULL, 0);
 155}
 156
 157static struct remote *make_remote(const char *name, int len)
 158{
 159        struct remote *ret, *replaced;
 160        struct remotes_hash_key lookup;
 161        struct hashmap_entry lookup_entry;
 162
 163        if (!len)
 164                len = strlen(name);
 165
 166        init_remotes_hash();
 167        lookup.str = name;
 168        lookup.len = len;
 169        hashmap_entry_init(&lookup_entry, memhash(name, len));
 170
 171        if ((ret = hashmap_get(&remotes_hash, &lookup_entry, &lookup)) != NULL)
 172                return ret;
 173
 174        ret = xcalloc(1, sizeof(struct remote));
 175        ret->prune = -1;  /* unspecified */
 176        ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 177        remotes[remotes_nr++] = ret;
 178        ret->name = xstrndup(name, len);
 179
 180        hashmap_entry_init(ret, lookup_entry.hash);
 181        replaced = hashmap_put(&remotes_hash, ret);
 182        assert(replaced == NULL);  /* no previous entry overwritten */
 183        return ret;
 184}
 185
 186static void add_merge(struct branch *branch, const char *name)
 187{
 188        ALLOC_GROW(branch->merge_name, branch->merge_nr + 1,
 189                   branch->merge_alloc);
 190        branch->merge_name[branch->merge_nr++] = name;
 191}
 192
 193static struct branch *make_branch(const char *name, int len)
 194{
 195        struct branch *ret;
 196        int i;
 197
 198        for (i = 0; i < branches_nr; i++) {
 199                if (len ? (!strncmp(name, branches[i]->name, len) &&
 200                           !branches[i]->name[len]) :
 201                    !strcmp(name, branches[i]->name))
 202                        return branches[i];
 203        }
 204
 205        ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 206        ret = xcalloc(1, sizeof(struct branch));
 207        branches[branches_nr++] = ret;
 208        if (len)
 209                ret->name = xstrndup(name, len);
 210        else
 211                ret->name = xstrdup(name);
 212        ret->refname = xstrfmt("refs/heads/%s", ret->name);
 213
 214        return ret;
 215}
 216
 217static struct rewrite *make_rewrite(struct rewrites *r, const char *base, int len)
 218{
 219        struct rewrite *ret;
 220        int i;
 221
 222        for (i = 0; i < r->rewrite_nr; i++) {
 223                if (len
 224                    ? (len == r->rewrite[i]->baselen &&
 225                       !strncmp(base, r->rewrite[i]->base, len))
 226                    : !strcmp(base, r->rewrite[i]->base))
 227                        return r->rewrite[i];
 228        }
 229
 230        ALLOC_GROW(r->rewrite, r->rewrite_nr + 1, r->rewrite_alloc);
 231        ret = xcalloc(1, sizeof(struct rewrite));
 232        r->rewrite[r->rewrite_nr++] = ret;
 233        if (len) {
 234                ret->base = xstrndup(base, len);
 235                ret->baselen = len;
 236        }
 237        else {
 238                ret->base = xstrdup(base);
 239                ret->baselen = strlen(base);
 240        }
 241        return ret;
 242}
 243
 244static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 245{
 246        ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 247        rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 248        rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 249        rewrite->instead_of_nr++;
 250}
 251
 252static const char *skip_spaces(const char *s)
 253{
 254        while (isspace(*s))
 255                s++;
 256        return s;
 257}
 258
 259static void read_remotes_file(struct remote *remote)
 260{
 261        struct strbuf buf = STRBUF_INIT;
 262        FILE *f = fopen_or_warn(git_path("remotes/%s", remote->name), "r");
 263
 264        if (!f)
 265                return;
 266        remote->configured_in_repo = 1;
 267        remote->origin = REMOTE_REMOTES;
 268        while (strbuf_getline(&buf, f) != EOF) {
 269                const char *v;
 270
 271                strbuf_rtrim(&buf);
 272
 273                if (skip_prefix(buf.buf, "URL:", &v))
 274                        add_url_alias(remote, xstrdup(skip_spaces(v)));
 275                else if (skip_prefix(buf.buf, "Push:", &v))
 276                        add_push_refspec(remote, xstrdup(skip_spaces(v)));
 277                else if (skip_prefix(buf.buf, "Pull:", &v))
 278                        add_fetch_refspec(remote, xstrdup(skip_spaces(v)));
 279        }
 280        strbuf_release(&buf);
 281        fclose(f);
 282}
 283
 284static void read_branches_file(struct remote *remote)
 285{
 286        char *frag;
 287        struct strbuf buf = STRBUF_INIT;
 288        FILE *f = fopen_or_warn(git_path("branches/%s", remote->name), "r");
 289
 290        if (!f)
 291                return;
 292
 293        strbuf_getline_lf(&buf, f);
 294        fclose(f);
 295        strbuf_trim(&buf);
 296        if (!buf.len) {
 297                strbuf_release(&buf);
 298                return;
 299        }
 300
 301        remote->configured_in_repo = 1;
 302        remote->origin = REMOTE_BRANCHES;
 303
 304        /*
 305         * The branches file would have URL and optionally
 306         * #branch specified.  The "master" (or specified) branch is
 307         * fetched and stored in the local branch matching the
 308         * remote name.
 309         */
 310        frag = strchr(buf.buf, '#');
 311        if (frag)
 312                *(frag++) = '\0';
 313        else
 314                frag = "master";
 315
 316        add_url_alias(remote, strbuf_detach(&buf, NULL));
 317        add_fetch_refspec(remote, xstrfmt("refs/heads/%s:refs/heads/%s",
 318                                          frag, remote->name));
 319
 320        /*
 321         * Cogito compatible push: push current HEAD to remote #branch
 322         * (master if missing)
 323         */
 324        add_push_refspec(remote, xstrfmt("HEAD:refs/heads/%s", frag));
 325        remote->fetch_tags = 1; /* always auto-follow */
 326}
 327
 328static int handle_config(const char *key, const char *value, void *cb)
 329{
 330        const char *name;
 331        int namelen;
 332        const char *subkey;
 333        struct remote *remote;
 334        struct branch *branch;
 335        if (parse_config_key(key, "branch", &name, &namelen, &subkey) >= 0) {
 336                if (!name)
 337                        return 0;
 338                branch = make_branch(name, namelen);
 339                if (!strcmp(subkey, "remote")) {
 340                        return git_config_string(&branch->remote_name, key, value);
 341                } else if (!strcmp(subkey, "pushremote")) {
 342                        return git_config_string(&branch->pushremote_name, key, value);
 343                } else if (!strcmp(subkey, "merge")) {
 344                        if (!value)
 345                                return config_error_nonbool(key);
 346                        add_merge(branch, xstrdup(value));
 347                }
 348                return 0;
 349        }
 350        if (parse_config_key(key, "url", &name, &namelen, &subkey) >= 0) {
 351                struct rewrite *rewrite;
 352                if (!name)
 353                        return 0;
 354                if (!strcmp(subkey, "insteadof")) {
 355                        rewrite = make_rewrite(&rewrites, name, namelen);
 356                        if (!value)
 357                                return config_error_nonbool(key);
 358                        add_instead_of(rewrite, xstrdup(value));
 359                } else if (!strcmp(subkey, "pushinsteadof")) {
 360                        rewrite = make_rewrite(&rewrites_push, name, namelen);
 361                        if (!value)
 362                                return config_error_nonbool(key);
 363                        add_instead_of(rewrite, xstrdup(value));
 364                }
 365        }
 366
 367        if (parse_config_key(key, "remote", &name, &namelen, &subkey) < 0)
 368                return 0;
 369
 370        /* Handle remote.* variables */
 371        if (!name && !strcmp(subkey, "pushdefault"))
 372                return git_config_string(&pushremote_name, key, value);
 373
 374        if (!name)
 375                return 0;
 376        /* Handle remote.<name>.* variables */
 377        if (*name == '/') {
 378                warning("Config remote shorthand cannot begin with '/': %s",
 379                        name);
 380                return 0;
 381        }
 382        remote = make_remote(name, namelen);
 383        remote->origin = REMOTE_CONFIG;
 384        if (current_config_scope() == CONFIG_SCOPE_REPO)
 385                remote->configured_in_repo = 1;
 386        if (!strcmp(subkey, "mirror"))
 387                remote->mirror = git_config_bool(key, value);
 388        else if (!strcmp(subkey, "skipdefaultupdate"))
 389                remote->skip_default_update = git_config_bool(key, value);
 390        else if (!strcmp(subkey, "skipfetchall"))
 391                remote->skip_default_update = git_config_bool(key, value);
 392        else if (!strcmp(subkey, "prune"))
 393                remote->prune = git_config_bool(key, value);
 394        else if (!strcmp(subkey, "url")) {
 395                const char *v;
 396                if (git_config_string(&v, key, value))
 397                        return -1;
 398                add_url(remote, v);
 399        } else if (!strcmp(subkey, "pushurl")) {
 400                const char *v;
 401                if (git_config_string(&v, key, value))
 402                        return -1;
 403                add_pushurl(remote, v);
 404        } else if (!strcmp(subkey, "push")) {
 405                const char *v;
 406                if (git_config_string(&v, key, value))
 407                        return -1;
 408                add_push_refspec(remote, v);
 409        } else if (!strcmp(subkey, "fetch")) {
 410                const char *v;
 411                if (git_config_string(&v, key, value))
 412                        return -1;
 413                add_fetch_refspec(remote, v);
 414        } else if (!strcmp(subkey, "receivepack")) {
 415                const char *v;
 416                if (git_config_string(&v, key, value))
 417                        return -1;
 418                if (!remote->receivepack)
 419                        remote->receivepack = v;
 420                else
 421                        error("more than one receivepack given, using the first");
 422        } else if (!strcmp(subkey, "uploadpack")) {
 423                const char *v;
 424                if (git_config_string(&v, key, value))
 425                        return -1;
 426                if (!remote->uploadpack)
 427                        remote->uploadpack = v;
 428                else
 429                        error("more than one uploadpack given, using the first");
 430        } else if (!strcmp(subkey, "tagopt")) {
 431                if (!strcmp(value, "--no-tags"))
 432                        remote->fetch_tags = -1;
 433                else if (!strcmp(value, "--tags"))
 434                        remote->fetch_tags = 2;
 435        } else if (!strcmp(subkey, "proxy")) {
 436                return git_config_string((const char **)&remote->http_proxy,
 437                                         key, value);
 438        } else if (!strcmp(subkey, "proxyauthmethod")) {
 439                return git_config_string((const char **)&remote->http_proxy_authmethod,
 440                                         key, value);
 441        } else if (!strcmp(subkey, "vcs")) {
 442                return git_config_string(&remote->foreign_vcs, key, value);
 443        }
 444        return 0;
 445}
 446
 447static void alias_all_urls(void)
 448{
 449        int i, j;
 450        for (i = 0; i < remotes_nr; i++) {
 451                int add_pushurl_aliases;
 452                if (!remotes[i])
 453                        continue;
 454                for (j = 0; j < remotes[i]->pushurl_nr; j++) {
 455                        remotes[i]->pushurl[j] = alias_url(remotes[i]->pushurl[j], &rewrites);
 456                }
 457                add_pushurl_aliases = remotes[i]->pushurl_nr == 0;
 458                for (j = 0; j < remotes[i]->url_nr; j++) {
 459                        if (add_pushurl_aliases)
 460                                add_pushurl_alias(remotes[i], remotes[i]->url[j]);
 461                        remotes[i]->url[j] = alias_url(remotes[i]->url[j], &rewrites);
 462                }
 463        }
 464}
 465
 466static void read_config(void)
 467{
 468        static int loaded;
 469        int flag;
 470
 471        if (loaded)
 472                return;
 473        loaded = 1;
 474
 475        current_branch = NULL;
 476        if (startup_info->have_repository) {
 477                const char *head_ref = resolve_ref_unsafe("HEAD", 0, NULL, &flag);
 478                if (head_ref && (flag & REF_ISSYMREF) &&
 479                    skip_prefix(head_ref, "refs/heads/", &head_ref)) {
 480                        current_branch = make_branch(head_ref, 0);
 481                }
 482        }
 483        git_config(handle_config, NULL);
 484        alias_all_urls();
 485}
 486
 487static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 488{
 489        int i;
 490        struct refspec *rs = xcalloc(nr_refspec, sizeof(*rs));
 491
 492        for (i = 0; i < nr_refspec; i++) {
 493                size_t llen;
 494                int is_glob;
 495                const char *lhs, *rhs;
 496                int flags;
 497
 498                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 pushing 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 = (1 <= rlen && strchr(rhs, '*'));
 520                        rs[i].dst = xstrndup(rhs, rlen);
 521                }
 522
 523                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 524                if (1 <= llen && memchr(lhs, '*', llen)) {
 525                        if ((rhs && !is_glob) || (!rhs && fetch))
 526                                goto invalid;
 527                        is_glob = 1;
 528                } else if (rhs && is_glob) {
 529                        goto invalid;
 530                }
 531
 532                rs[i].pattern = is_glob;
 533                rs[i].src = xstrndup(lhs, llen);
 534                flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 535
 536                if (fetch) {
 537                        struct object_id unused;
 538
 539                        /* LHS */
 540                        if (!*rs[i].src)
 541                                ; /* empty is ok; it means "HEAD" */
 542                        else if (llen == GIT_SHA1_HEXSZ && !get_oid_hex(rs[i].src, &unused))
 543                                rs[i].exact_sha1 = 1; /* ok */
 544                        else if (!check_refname_format(rs[i].src, flags))
 545                                ; /* valid looking ref is ok */
 546                        else
 547                                goto invalid;
 548                        /* RHS */
 549                        if (!rs[i].dst)
 550                                ; /* missing is ok; it is the same as empty */
 551                        else if (!*rs[i].dst)
 552                                ; /* empty is ok; it means "do not store" */
 553                        else if (!check_refname_format(rs[i].dst, flags))
 554                                ; /* valid looking ref is ok */
 555                        else
 556                                goto invalid;
 557                } else {
 558                        /*
 559                         * LHS
 560                         * - empty is allowed; it means delete.
 561                         * - when wildcarded, it must be a valid looking ref.
 562                         * - otherwise, it must be an extended SHA-1, but
 563                         *   there is no existing way to validate this.
 564                         */
 565                        if (!*rs[i].src)
 566                                ; /* empty is ok */
 567                        else if (is_glob) {
 568                                if (check_refname_format(rs[i].src, flags))
 569                                        goto invalid;
 570                        }
 571                        else
 572                                ; /* anything goes, for now */
 573                        /*
 574                         * RHS
 575                         * - missing is allowed, but LHS then must be a
 576                         *   valid looking ref.
 577                         * - empty is not allowed.
 578                         * - otherwise it must be a valid looking ref.
 579                         */
 580                        if (!rs[i].dst) {
 581                                if (check_refname_format(rs[i].src, flags))
 582                                        goto invalid;
 583                        } else if (!*rs[i].dst) {
 584                                goto invalid;
 585                        } else {
 586                                if (check_refname_format(rs[i].dst, flags))
 587                                        goto invalid;
 588                        }
 589                }
 590        }
 591        return rs;
 592
 593 invalid:
 594        if (verify) {
 595                /*
 596                 * nr_refspec must be greater than zero and i must be valid
 597                 * since it is only possible to reach this point from within
 598                 * the for loop above.
 599                 */
 600                free_refspec(i+1, rs);
 601                return NULL;
 602        }
 603        die("Invalid refspec '%s'", refspec[i]);
 604}
 605
 606int valid_fetch_refspec(const char *fetch_refspec_str)
 607{
 608        struct refspec *refspec;
 609
 610        refspec = parse_refspec_internal(1, &fetch_refspec_str, 1, 1);
 611        free_refspec(1, refspec);
 612        return !!refspec;
 613}
 614
 615struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 616{
 617        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 618}
 619
 620struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 621{
 622        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 623}
 624
 625void free_refspec(int nr_refspec, struct refspec *refspec)
 626{
 627        int i;
 628
 629        if (!refspec)
 630                return;
 631
 632        for (i = 0; i < nr_refspec; i++) {
 633                free(refspec[i].src);
 634                free(refspec[i].dst);
 635        }
 636        free(refspec);
 637}
 638
 639static int valid_remote_nick(const char *name)
 640{
 641        if (!name[0] || is_dot_or_dotdot(name))
 642                return 0;
 643
 644        /* remote nicknames cannot contain slashes */
 645        while (*name)
 646                if (is_dir_sep(*name++))
 647                        return 0;
 648        return 1;
 649}
 650
 651const char *remote_for_branch(struct branch *branch, int *explicit)
 652{
 653        if (branch && branch->remote_name) {
 654                if (explicit)
 655                        *explicit = 1;
 656                return branch->remote_name;
 657        }
 658        if (explicit)
 659                *explicit = 0;
 660        return "origin";
 661}
 662
 663const char *pushremote_for_branch(struct branch *branch, int *explicit)
 664{
 665        if (branch && branch->pushremote_name) {
 666                if (explicit)
 667                        *explicit = 1;
 668                return branch->pushremote_name;
 669        }
 670        if (pushremote_name) {
 671                if (explicit)
 672                        *explicit = 1;
 673                return pushremote_name;
 674        }
 675        return remote_for_branch(branch, explicit);
 676}
 677
 678static struct remote *remote_get_1(const char *name,
 679                                   const char *(*get_default)(struct branch *, int *))
 680{
 681        struct remote *ret;
 682        int name_given = 0;
 683
 684        read_config();
 685
 686        if (name)
 687                name_given = 1;
 688        else
 689                name = get_default(current_branch, &name_given);
 690
 691        ret = make_remote(name, 0);
 692        if (valid_remote_nick(name) && have_git_dir()) {
 693                if (!valid_remote(ret))
 694                        read_remotes_file(ret);
 695                if (!valid_remote(ret))
 696                        read_branches_file(ret);
 697        }
 698        if (name_given && !valid_remote(ret))
 699                add_url_alias(ret, name);
 700        if (!valid_remote(ret))
 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
 707struct remote *remote_get(const char *name)
 708{
 709        return remote_get_1(name, remote_for_branch);
 710}
 711
 712struct remote *pushremote_get(const char *name)
 713{
 714        return remote_get_1(name, pushremote_for_branch);
 715}
 716
 717int remote_is_configured(struct remote *remote, int in_repo)
 718{
 719        if (!remote)
 720                return 0;
 721        if (in_repo)
 722                return remote->configured_in_repo;
 723        return !!remote->origin;
 724}
 725
 726int for_each_remote(each_remote_fn fn, void *priv)
 727{
 728        int i, result = 0;
 729        read_config();
 730        for (i = 0; i < remotes_nr && !result; i++) {
 731                struct remote *r = remotes[i];
 732                if (!r)
 733                        continue;
 734                if (!r->fetch)
 735                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 736                                                       r->fetch_refspec);
 737                if (!r->push)
 738                        r->push = parse_push_refspec(r->push_refspec_nr,
 739                                                     r->push_refspec);
 740                result = fn(r, priv);
 741        }
 742        return result;
 743}
 744
 745static void handle_duplicate(struct ref *ref1, struct ref *ref2)
 746{
 747        if (strcmp(ref1->name, ref2->name)) {
 748                if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 749                    ref2->fetch_head_status != FETCH_HEAD_IGNORE) {
 750                        die(_("Cannot fetch both %s and %s to %s"),
 751                            ref1->name, ref2->name, ref2->peer_ref->name);
 752                } else if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 753                           ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 754                        warning(_("%s usually tracks %s, not %s"),
 755                                ref2->peer_ref->name, ref2->name, ref1->name);
 756                } else if (ref1->fetch_head_status == FETCH_HEAD_IGNORE &&
 757                           ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 758                        die(_("%s tracks both %s and %s"),
 759                            ref2->peer_ref->name, ref1->name, ref2->name);
 760                } else {
 761                        /*
 762                         * This last possibility doesn't occur because
 763                         * FETCH_HEAD_IGNORE entries always appear at
 764                         * the end of the list.
 765                         */
 766                        die(_("Internal error"));
 767                }
 768        }
 769        free(ref2->peer_ref);
 770        free(ref2);
 771}
 772
 773struct ref *ref_remove_duplicates(struct ref *ref_map)
 774{
 775        struct string_list refs = STRING_LIST_INIT_NODUP;
 776        struct ref *retval = NULL;
 777        struct ref **p = &retval;
 778
 779        while (ref_map) {
 780                struct ref *ref = ref_map;
 781
 782                ref_map = ref_map->next;
 783                ref->next = NULL;
 784
 785                if (!ref->peer_ref) {
 786                        *p = ref;
 787                        p = &ref->next;
 788                } else {
 789                        struct string_list_item *item =
 790                                string_list_insert(&refs, ref->peer_ref->name);
 791
 792                        if (item->util) {
 793                                /* Entry already existed */
 794                                handle_duplicate((struct ref *)item->util, ref);
 795                        } else {
 796                                *p = ref;
 797                                p = &ref->next;
 798                                item->util = ref;
 799                        }
 800                }
 801        }
 802
 803        string_list_clear(&refs, 0);
 804        return retval;
 805}
 806
 807int remote_has_url(struct remote *remote, const char *url)
 808{
 809        int i;
 810        for (i = 0; i < remote->url_nr; i++) {
 811                if (!strcmp(remote->url[i], url))
 812                        return 1;
 813        }
 814        return 0;
 815}
 816
 817static int match_name_with_pattern(const char *key, const char *name,
 818                                   const char *value, char **result)
 819{
 820        const char *kstar = strchr(key, '*');
 821        size_t klen;
 822        size_t ksuffixlen;
 823        size_t namelen;
 824        int ret;
 825        if (!kstar)
 826                die("Key '%s' of pattern had no '*'", key);
 827        klen = kstar - key;
 828        ksuffixlen = strlen(kstar + 1);
 829        namelen = strlen(name);
 830        ret = !strncmp(name, key, klen) && namelen >= klen + ksuffixlen &&
 831                !memcmp(name + namelen - ksuffixlen, kstar + 1, ksuffixlen);
 832        if (ret && value) {
 833                struct strbuf sb = STRBUF_INIT;
 834                const char *vstar = strchr(value, '*');
 835                if (!vstar)
 836                        die("Value '%s' of pattern has no '*'", value);
 837                strbuf_add(&sb, value, vstar - value);
 838                strbuf_add(&sb, name + klen, namelen - klen - ksuffixlen);
 839                strbuf_addstr(&sb, vstar + 1);
 840                *result = strbuf_detach(&sb, NULL);
 841        }
 842        return ret;
 843}
 844
 845static void query_refspecs_multiple(struct refspec *refs, int ref_count, struct refspec *query, struct string_list *results)
 846{
 847        int i;
 848        int find_src = !query->src;
 849
 850        if (find_src && !query->dst)
 851                error("query_refspecs_multiple: need either src or dst");
 852
 853        for (i = 0; i < ref_count; i++) {
 854                struct refspec *refspec = &refs[i];
 855                const char *key = find_src ? refspec->dst : refspec->src;
 856                const char *value = find_src ? refspec->src : refspec->dst;
 857                const char *needle = find_src ? query->dst : query->src;
 858                char **result = find_src ? &query->src : &query->dst;
 859
 860                if (!refspec->dst)
 861                        continue;
 862                if (refspec->pattern) {
 863                        if (match_name_with_pattern(key, needle, value, result))
 864                                string_list_append_nodup(results, *result);
 865                } else if (!strcmp(needle, key)) {
 866                        string_list_append(results, value);
 867                }
 868        }
 869}
 870
 871int query_refspecs(struct refspec *refs, int ref_count, struct refspec *query)
 872{
 873        int i;
 874        int find_src = !query->src;
 875        const char *needle = find_src ? query->dst : query->src;
 876        char **result = find_src ? &query->src : &query->dst;
 877
 878        if (find_src && !query->dst)
 879                return error("query_refspecs: need either src or dst");
 880
 881        for (i = 0; i < ref_count; i++) {
 882                struct refspec *refspec = &refs[i];
 883                const char *key = find_src ? refspec->dst : refspec->src;
 884                const char *value = find_src ? refspec->src : refspec->dst;
 885
 886                if (!refspec->dst)
 887                        continue;
 888                if (refspec->pattern) {
 889                        if (match_name_with_pattern(key, needle, value, result)) {
 890                                query->force = refspec->force;
 891                                return 0;
 892                        }
 893                } else if (!strcmp(needle, key)) {
 894                        *result = xstrdup(value);
 895                        query->force = refspec->force;
 896                        return 0;
 897                }
 898        }
 899        return -1;
 900}
 901
 902char *apply_refspecs(struct refspec *refspecs, int nr_refspec,
 903                     const char *name)
 904{
 905        struct refspec query;
 906
 907        memset(&query, 0, sizeof(struct refspec));
 908        query.src = (char *)name;
 909
 910        if (query_refspecs(refspecs, nr_refspec, &query))
 911                return NULL;
 912
 913        return query.dst;
 914}
 915
 916int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 917{
 918        return query_refspecs(remote->fetch, remote->fetch_refspec_nr, refspec);
 919}
 920
 921static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 922                const char *name)
 923{
 924        size_t len = strlen(name);
 925        struct ref *ref = xcalloc(1, st_add4(sizeof(*ref), prefixlen, len, 1));
 926        memcpy(ref->name, prefix, prefixlen);
 927        memcpy(ref->name + prefixlen, name, len);
 928        return ref;
 929}
 930
 931struct ref *alloc_ref(const char *name)
 932{
 933        return alloc_ref_with_prefix("", 0, name);
 934}
 935
 936struct ref *copy_ref(const struct ref *ref)
 937{
 938        struct ref *cpy;
 939        size_t len;
 940        if (!ref)
 941                return NULL;
 942        len = st_add3(sizeof(struct ref), strlen(ref->name), 1);
 943        cpy = xmalloc(len);
 944        memcpy(cpy, ref, len);
 945        cpy->next = NULL;
 946        cpy->symref = xstrdup_or_null(ref->symref);
 947        cpy->remote_status = xstrdup_or_null(ref->remote_status);
 948        cpy->peer_ref = copy_ref(ref->peer_ref);
 949        return cpy;
 950}
 951
 952struct ref *copy_ref_list(const struct ref *ref)
 953{
 954        struct ref *ret = NULL;
 955        struct ref **tail = &ret;
 956        while (ref) {
 957                *tail = copy_ref(ref);
 958                ref = ref->next;
 959                tail = &((*tail)->next);
 960        }
 961        return ret;
 962}
 963
 964static void free_ref(struct ref *ref)
 965{
 966        if (!ref)
 967                return;
 968        free_ref(ref->peer_ref);
 969        free(ref->remote_status);
 970        free(ref->symref);
 971        free(ref);
 972}
 973
 974void free_refs(struct ref *ref)
 975{
 976        struct ref *next;
 977        while (ref) {
 978                next = ref->next;
 979                free_ref(ref);
 980                ref = next;
 981        }
 982}
 983
 984int ref_compare_name(const void *va, const void *vb)
 985{
 986        const struct ref *a = va, *b = vb;
 987        return strcmp(a->name, b->name);
 988}
 989
 990static void *ref_list_get_next(const void *a)
 991{
 992        return ((const struct ref *)a)->next;
 993}
 994
 995static void ref_list_set_next(void *a, void *next)
 996{
 997        ((struct ref *)a)->next = next;
 998}
 999
1000void sort_ref_list(struct ref **l, int (*cmp)(const void *, const void *))
1001{
1002        *l = llist_mergesort(*l, ref_list_get_next, ref_list_set_next, cmp);
1003}
1004
1005int count_refspec_match(const char *pattern,
1006                        struct ref *refs,
1007                        struct ref **matched_ref)
1008{
1009        int patlen = strlen(pattern);
1010        struct ref *matched_weak = NULL;
1011        struct ref *matched = NULL;
1012        int weak_match = 0;
1013        int match = 0;
1014
1015        for (weak_match = match = 0; refs; refs = refs->next) {
1016                char *name = refs->name;
1017                int namelen = strlen(name);
1018
1019                if (!refname_match(pattern, name))
1020                        continue;
1021
1022                /* A match is "weak" if it is with refs outside
1023                 * heads or tags, and did not specify the pattern
1024                 * in full (e.g. "refs/remotes/origin/master") or at
1025                 * least from the toplevel (e.g. "remotes/origin/master");
1026                 * otherwise "git push $URL master" would result in
1027                 * ambiguity between remotes/origin/master and heads/master
1028                 * at the remote site.
1029                 */
1030                if (namelen != patlen &&
1031                    patlen != namelen - 5 &&
1032                    !starts_with(name, "refs/heads/") &&
1033                    !starts_with(name, "refs/tags/")) {
1034                        /* We want to catch the case where only weak
1035                         * matches are found and there are multiple
1036                         * matches, and where more than one strong
1037                         * matches are found, as ambiguous.  One
1038                         * strong match with zero or more weak matches
1039                         * are acceptable as a unique match.
1040                         */
1041                        matched_weak = refs;
1042                        weak_match++;
1043                }
1044                else {
1045                        matched = refs;
1046                        match++;
1047                }
1048        }
1049        if (!matched) {
1050                if (matched_ref)
1051                        *matched_ref = matched_weak;
1052                return weak_match;
1053        }
1054        else {
1055                if (matched_ref)
1056                        *matched_ref = matched;
1057                return match;
1058        }
1059}
1060
1061static void tail_link_ref(struct ref *ref, struct ref ***tail)
1062{
1063        **tail = ref;
1064        while (ref->next)
1065                ref = ref->next;
1066        *tail = &ref->next;
1067}
1068
1069static struct ref *alloc_delete_ref(void)
1070{
1071        struct ref *ref = alloc_ref("(delete)");
1072        oidclr(&ref->new_oid);
1073        return ref;
1074}
1075
1076static int try_explicit_object_name(const char *name,
1077                                    struct ref **match)
1078{
1079        struct object_id oid;
1080
1081        if (!*name) {
1082                if (match)
1083                        *match = alloc_delete_ref();
1084                return 0;
1085        }
1086
1087        if (get_oid(name, &oid))
1088                return -1;
1089
1090        if (match) {
1091                *match = alloc_ref(name);
1092                oidcpy(&(*match)->new_oid, &oid);
1093        }
1094        return 0;
1095}
1096
1097static struct ref *make_linked_ref(const char *name, struct ref ***tail)
1098{
1099        struct ref *ret = alloc_ref(name);
1100        tail_link_ref(ret, tail);
1101        return ret;
1102}
1103
1104static char *guess_ref(const char *name, struct ref *peer)
1105{
1106        struct strbuf buf = STRBUF_INIT;
1107
1108        const char *r = resolve_ref_unsafe(peer->name, RESOLVE_REF_READING,
1109                                           NULL, NULL);
1110        if (!r)
1111                return NULL;
1112
1113        if (starts_with(r, "refs/heads/"))
1114                strbuf_addstr(&buf, "refs/heads/");
1115        else if (starts_with(r, "refs/tags/"))
1116                strbuf_addstr(&buf, "refs/tags/");
1117        else
1118                return NULL;
1119
1120        strbuf_addstr(&buf, name);
1121        return strbuf_detach(&buf, NULL);
1122}
1123
1124static int match_explicit_lhs(struct ref *src,
1125                              struct refspec *rs,
1126                              struct ref **match,
1127                              int *allocated_match)
1128{
1129        switch (count_refspec_match(rs->src, src, match)) {
1130        case 1:
1131                if (allocated_match)
1132                        *allocated_match = 0;
1133                return 0;
1134        case 0:
1135                /* The source could be in the get_sha1() format
1136                 * not a reference name.  :refs/other is a
1137                 * way to delete 'other' ref at the remote end.
1138                 */
1139                if (try_explicit_object_name(rs->src, match) < 0)
1140                        return error("src refspec %s does not match any.", rs->src);
1141                if (allocated_match)
1142                        *allocated_match = 1;
1143                return 0;
1144        default:
1145                return error("src refspec %s matches more than one.", rs->src);
1146        }
1147}
1148
1149static int match_explicit(struct ref *src, struct ref *dst,
1150                          struct ref ***dst_tail,
1151                          struct refspec *rs)
1152{
1153        struct ref *matched_src, *matched_dst;
1154        int allocated_src;
1155
1156        const char *dst_value = rs->dst;
1157        char *dst_guess;
1158
1159        if (rs->pattern || rs->matching)
1160                return 0;
1161
1162        matched_src = matched_dst = NULL;
1163        if (match_explicit_lhs(src, rs, &matched_src, &allocated_src) < 0)
1164                return -1;
1165
1166        if (!dst_value) {
1167                int flag;
1168
1169                dst_value = resolve_ref_unsafe(matched_src->name,
1170                                               RESOLVE_REF_READING,
1171                                               NULL, &flag);
1172                if (!dst_value ||
1173                    ((flag & REF_ISSYMREF) &&
1174                     !starts_with(dst_value, "refs/heads/")))
1175                        die("%s cannot be resolved to branch.",
1176                            matched_src->name);
1177        }
1178
1179        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
1180        case 1:
1181                break;
1182        case 0:
1183                if (starts_with(dst_value, "refs/"))
1184                        matched_dst = make_linked_ref(dst_value, dst_tail);
1185                else if (is_null_oid(&matched_src->new_oid))
1186                        error("unable to delete '%s': remote ref does not exist",
1187                              dst_value);
1188                else if ((dst_guess = guess_ref(dst_value, matched_src))) {
1189                        matched_dst = make_linked_ref(dst_guess, dst_tail);
1190                        free(dst_guess);
1191                } else
1192                        error("unable to push to unqualified destination: %s\n"
1193                              "The destination refspec neither matches an "
1194                              "existing ref on the remote nor\n"
1195                              "begins with refs/, and we are unable to "
1196                              "guess a prefix based on the source ref.",
1197                              dst_value);
1198                break;
1199        default:
1200                matched_dst = NULL;
1201                error("dst refspec %s matches more than one.",
1202                      dst_value);
1203                break;
1204        }
1205        if (!matched_dst)
1206                return -1;
1207        if (matched_dst->peer_ref)
1208                return error("dst ref %s receives from more than one src.",
1209                      matched_dst->name);
1210        else {
1211                matched_dst->peer_ref = allocated_src ?
1212                                        matched_src :
1213                                        copy_ref(matched_src);
1214                matched_dst->force = rs->force;
1215        }
1216        return 0;
1217}
1218
1219static int match_explicit_refs(struct ref *src, struct ref *dst,
1220                               struct ref ***dst_tail, struct refspec *rs,
1221                               int rs_nr)
1222{
1223        int i, errs;
1224        for (i = errs = 0; i < rs_nr; i++)
1225                errs += match_explicit(src, dst, dst_tail, &rs[i]);
1226        return errs;
1227}
1228
1229static char *get_ref_match(const struct refspec *rs, int rs_nr, const struct ref *ref,
1230                int send_mirror, int direction, const struct refspec **ret_pat)
1231{
1232        const struct refspec *pat;
1233        char *name;
1234        int i;
1235        int matching_refs = -1;
1236        for (i = 0; i < rs_nr; i++) {
1237                if (rs[i].matching &&
1238                    (matching_refs == -1 || rs[i].force)) {
1239                        matching_refs = i;
1240                        continue;
1241                }
1242
1243                if (rs[i].pattern) {
1244                        const char *dst_side = rs[i].dst ? rs[i].dst : rs[i].src;
1245                        int match;
1246                        if (direction == FROM_SRC)
1247                                match = match_name_with_pattern(rs[i].src, ref->name, dst_side, &name);
1248                        else
1249                                match = match_name_with_pattern(dst_side, ref->name, rs[i].src, &name);
1250                        if (match) {
1251                                matching_refs = i;
1252                                break;
1253                        }
1254                }
1255        }
1256        if (matching_refs == -1)
1257                return NULL;
1258
1259        pat = rs + matching_refs;
1260        if (pat->matching) {
1261                /*
1262                 * "matching refs"; traditionally we pushed everything
1263                 * including refs outside refs/heads/ hierarchy, but
1264                 * that does not make much sense these days.
1265                 */
1266                if (!send_mirror && !starts_with(ref->name, "refs/heads/"))
1267                        return NULL;
1268                name = xstrdup(ref->name);
1269        }
1270        if (ret_pat)
1271                *ret_pat = pat;
1272        return name;
1273}
1274
1275static struct ref **tail_ref(struct ref **head)
1276{
1277        struct ref **tail = head;
1278        while (*tail)
1279                tail = &((*tail)->next);
1280        return tail;
1281}
1282
1283struct tips {
1284        struct commit **tip;
1285        int nr, alloc;
1286};
1287
1288static void add_to_tips(struct tips *tips, const struct object_id *oid)
1289{
1290        struct commit *commit;
1291
1292        if (is_null_oid(oid))
1293                return;
1294        commit = lookup_commit_reference_gently(oid, 1);
1295        if (!commit || (commit->object.flags & TMP_MARK))
1296                return;
1297        commit->object.flags |= TMP_MARK;
1298        ALLOC_GROW(tips->tip, tips->nr + 1, tips->alloc);
1299        tips->tip[tips->nr++] = commit;
1300}
1301
1302static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***dst_tail)
1303{
1304        struct string_list dst_tag = STRING_LIST_INIT_NODUP;
1305        struct string_list src_tag = STRING_LIST_INIT_NODUP;
1306        struct string_list_item *item;
1307        struct ref *ref;
1308        struct tips sent_tips;
1309
1310        /*
1311         * Collect everything we know they would have at the end of
1312         * this push, and collect all tags they have.
1313         */
1314        memset(&sent_tips, 0, sizeof(sent_tips));
1315        for (ref = *dst; ref; ref = ref->next) {
1316                if (ref->peer_ref &&
1317                    !is_null_oid(&ref->peer_ref->new_oid))
1318                        add_to_tips(&sent_tips, &ref->peer_ref->new_oid);
1319                else
1320                        add_to_tips(&sent_tips, &ref->old_oid);
1321                if (starts_with(ref->name, "refs/tags/"))
1322                        string_list_append(&dst_tag, ref->name);
1323        }
1324        clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
1325
1326        string_list_sort(&dst_tag);
1327
1328        /* Collect tags they do not have. */
1329        for (ref = src; ref; ref = ref->next) {
1330                if (!starts_with(ref->name, "refs/tags/"))
1331                        continue; /* not a tag */
1332                if (string_list_has_string(&dst_tag, ref->name))
1333                        continue; /* they already have it */
1334                if (sha1_object_info(ref->new_oid.hash, NULL) != OBJ_TAG)
1335                        continue; /* be conservative */
1336                item = string_list_append(&src_tag, ref->name);
1337                item->util = ref;
1338        }
1339        string_list_clear(&dst_tag, 0);
1340
1341        /*
1342         * At this point, src_tag lists tags that are missing from
1343         * dst, and sent_tips lists the tips we are pushing or those
1344         * that we know they already have. An element in the src_tag
1345         * that is an ancestor of any of the sent_tips needs to be
1346         * sent to the other side.
1347         */
1348        if (sent_tips.nr) {
1349                for_each_string_list_item(item, &src_tag) {
1350                        struct ref *ref = item->util;
1351                        struct ref *dst_ref;
1352                        struct commit *commit;
1353
1354                        if (is_null_oid(&ref->new_oid))
1355                                continue;
1356                        commit = lookup_commit_reference_gently(&ref->new_oid,
1357                                                                1);
1358                        if (!commit)
1359                                /* not pushing a commit, which is not an error */
1360                                continue;
1361
1362                        /*
1363                         * Is this tag, which they do not have, reachable from
1364                         * any of the commits we are sending?
1365                         */
1366                        if (!in_merge_bases_many(commit, sent_tips.nr, sent_tips.tip))
1367                                continue;
1368
1369                        /* Add it in */
1370                        dst_ref = make_linked_ref(ref->name, dst_tail);
1371                        oidcpy(&dst_ref->new_oid, &ref->new_oid);
1372                        dst_ref->peer_ref = copy_ref(ref);
1373                }
1374        }
1375        string_list_clear(&src_tag, 0);
1376        free(sent_tips.tip);
1377}
1378
1379struct ref *find_ref_by_name(const struct ref *list, const char *name)
1380{
1381        for ( ; list; list = list->next)
1382                if (!strcmp(list->name, name))
1383                        return (struct ref *)list;
1384        return NULL;
1385}
1386
1387static void prepare_ref_index(struct string_list *ref_index, struct ref *ref)
1388{
1389        for ( ; ref; ref = ref->next)
1390                string_list_append_nodup(ref_index, ref->name)->util = ref;
1391
1392        string_list_sort(ref_index);
1393}
1394
1395/*
1396 * Given only the set of local refs, sanity-check the set of push
1397 * refspecs. We can't catch all errors that match_push_refs would,
1398 * but we can catch some errors early before even talking to the
1399 * remote side.
1400 */
1401int check_push_refs(struct ref *src, int nr_refspec, const char **refspec_names)
1402{
1403        struct refspec *refspec = parse_push_refspec(nr_refspec, refspec_names);
1404        int ret = 0;
1405        int i;
1406
1407        for (i = 0; i < nr_refspec; i++) {
1408                struct refspec *rs = refspec + i;
1409
1410                if (rs->pattern || rs->matching)
1411                        continue;
1412
1413                ret |= match_explicit_lhs(src, rs, NULL, NULL);
1414        }
1415
1416        free_refspec(nr_refspec, refspec);
1417        return ret;
1418}
1419
1420/*
1421 * Given the set of refs the local repository has, the set of refs the
1422 * remote repository has, and the refspec used for push, determine
1423 * what remote refs we will update and with what value by setting
1424 * peer_ref (which object is being pushed) and force (if the push is
1425 * forced) in elements of "dst". The function may add new elements to
1426 * dst (e.g. pushing to a new branch, done in match_explicit_refs).
1427 */
1428int match_push_refs(struct ref *src, struct ref **dst,
1429                    int nr_refspec, const char **refspec, int flags)
1430{
1431        struct refspec *rs;
1432        int send_all = flags & MATCH_REFS_ALL;
1433        int send_mirror = flags & MATCH_REFS_MIRROR;
1434        int send_prune = flags & MATCH_REFS_PRUNE;
1435        int errs;
1436        static const char *default_refspec[] = { ":", NULL };
1437        struct ref *ref, **dst_tail = tail_ref(dst);
1438        struct string_list dst_ref_index = STRING_LIST_INIT_NODUP;
1439
1440        if (!nr_refspec) {
1441                nr_refspec = 1;
1442                refspec = default_refspec;
1443        }
1444        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1445        errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
1446
1447        /* pick the remainder */
1448        for (ref = src; ref; ref = ref->next) {
1449                struct string_list_item *dst_item;
1450                struct ref *dst_peer;
1451                const struct refspec *pat = NULL;
1452                char *dst_name;
1453
1454                dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
1455                if (!dst_name)
1456                        continue;
1457
1458                if (!dst_ref_index.nr)
1459                        prepare_ref_index(&dst_ref_index, *dst);
1460
1461                dst_item = string_list_lookup(&dst_ref_index, dst_name);
1462                dst_peer = dst_item ? dst_item->util : NULL;
1463                if (dst_peer) {
1464                        if (dst_peer->peer_ref)
1465                                /* We're already sending something to this ref. */
1466                                goto free_name;
1467                } else {
1468                        if (pat->matching && !(send_all || send_mirror))
1469                                /*
1470                                 * Remote doesn't have it, and we have no
1471                                 * explicit pattern, and we don't have
1472                                 * --all or --mirror.
1473                                 */
1474                                goto free_name;
1475
1476                        /* Create a new one and link it */
1477                        dst_peer = make_linked_ref(dst_name, &dst_tail);
1478                        oidcpy(&dst_peer->new_oid, &ref->new_oid);
1479                        string_list_insert(&dst_ref_index,
1480                                dst_peer->name)->util = dst_peer;
1481                }
1482                dst_peer->peer_ref = copy_ref(ref);
1483                dst_peer->force = pat->force;
1484        free_name:
1485                free(dst_name);
1486        }
1487
1488        string_list_clear(&dst_ref_index, 0);
1489
1490        if (flags & MATCH_REFS_FOLLOW_TAGS)
1491                add_missing_tags(src, dst, &dst_tail);
1492
1493        if (send_prune) {
1494                struct string_list src_ref_index = STRING_LIST_INIT_NODUP;
1495                /* check for missing refs on the remote */
1496                for (ref = *dst; ref; ref = ref->next) {
1497                        char *src_name;
1498
1499                        if (ref->peer_ref)
1500                                /* We're already sending something to this ref. */
1501                                continue;
1502
1503                        src_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_DST, NULL);
1504                        if (src_name) {
1505                                if (!src_ref_index.nr)
1506                                        prepare_ref_index(&src_ref_index, src);
1507                                if (!string_list_has_string(&src_ref_index,
1508                                            src_name))
1509                                        ref->peer_ref = alloc_delete_ref();
1510                                free(src_name);
1511                        }
1512                }
1513                string_list_clear(&src_ref_index, 0);
1514        }
1515        if (errs)
1516                return -1;
1517        return 0;
1518}
1519
1520void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
1521                             int force_update)
1522{
1523        struct ref *ref;
1524
1525        for (ref = remote_refs; ref; ref = ref->next) {
1526                int force_ref_update = ref->force || force_update;
1527                int reject_reason = 0;
1528
1529                if (ref->peer_ref)
1530                        oidcpy(&ref->new_oid, &ref->peer_ref->new_oid);
1531                else if (!send_mirror)
1532                        continue;
1533
1534                ref->deletion = is_null_oid(&ref->new_oid);
1535                if (!ref->deletion &&
1536                        !oidcmp(&ref->old_oid, &ref->new_oid)) {
1537                        ref->status = REF_STATUS_UPTODATE;
1538                        continue;
1539                }
1540
1541                /*
1542                 * If the remote ref has moved and is now different
1543                 * from what we expect, reject any push.
1544                 *
1545                 * It also is an error if the user told us to check
1546                 * with the remote-tracking branch to find the value
1547                 * to expect, but we did not have such a tracking
1548                 * branch.
1549                 */
1550                if (ref->expect_old_sha1) {
1551                        if (oidcmp(&ref->old_oid, &ref->old_oid_expect))
1552                                reject_reason = REF_STATUS_REJECT_STALE;
1553                        else
1554                                /* If the ref isn't stale then force the update. */
1555                                force_ref_update = 1;
1556                }
1557
1558                /*
1559                 * If the update isn't already rejected then check
1560                 * the usual "must fast-forward" rules.
1561                 *
1562                 * Decide whether an individual refspec A:B can be
1563                 * pushed.  The push will succeed if any of the
1564                 * following are true:
1565                 *
1566                 * (1) the remote reference B does not exist
1567                 *
1568                 * (2) the remote reference B is being removed (i.e.,
1569                 *     pushing :B where no source is specified)
1570                 *
1571                 * (3) the destination is not under refs/tags/, and
1572                 *     if the old and new value is a commit, the new
1573                 *     is a descendant of the old.
1574                 *
1575                 * (4) it is forced using the +A:B notation, or by
1576                 *     passing the --force argument
1577                 */
1578
1579                if (!reject_reason && !ref->deletion && !is_null_oid(&ref->old_oid)) {
1580                        if (starts_with(ref->name, "refs/tags/"))
1581                                reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
1582                        else if (!has_object_file(&ref->old_oid))
1583                                reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
1584                        else if (!lookup_commit_reference_gently(&ref->old_oid, 1) ||
1585                                 !lookup_commit_reference_gently(&ref->new_oid, 1))
1586                                reject_reason = REF_STATUS_REJECT_NEEDS_FORCE;
1587                        else if (!ref_newer(&ref->new_oid, &ref->old_oid))
1588                                reject_reason = REF_STATUS_REJECT_NONFASTFORWARD;
1589                }
1590
1591                /*
1592                 * "--force" will defeat any rejection implemented
1593                 * by the rules above.
1594                 */
1595                if (!force_ref_update)
1596                        ref->status = reject_reason;
1597                else if (reject_reason)
1598                        ref->forced_update = 1;
1599        }
1600}
1601
1602static void set_merge(struct branch *ret)
1603{
1604        struct remote *remote;
1605        char *ref;
1606        struct object_id oid;
1607        int i;
1608
1609        if (!ret)
1610                return; /* no branch */
1611        if (ret->merge)
1612                return; /* already run */
1613        if (!ret->remote_name || !ret->merge_nr) {
1614                /*
1615                 * no merge config; let's make sure we don't confuse callers
1616                 * with a non-zero merge_nr but a NULL merge
1617                 */
1618                ret->merge_nr = 0;
1619                return;
1620        }
1621
1622        remote = remote_get(ret->remote_name);
1623
1624        ret->merge = xcalloc(ret->merge_nr, sizeof(*ret->merge));
1625        for (i = 0; i < ret->merge_nr; i++) {
1626                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1627                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1628                if (!remote_find_tracking(remote, ret->merge[i]) ||
1629                    strcmp(ret->remote_name, "."))
1630                        continue;
1631                if (dwim_ref(ret->merge_name[i], strlen(ret->merge_name[i]),
1632                             &oid, &ref) == 1)
1633                        ret->merge[i]->dst = ref;
1634                else
1635                        ret->merge[i]->dst = xstrdup(ret->merge_name[i]);
1636        }
1637}
1638
1639struct branch *branch_get(const char *name)
1640{
1641        struct branch *ret;
1642
1643        read_config();
1644        if (!name || !*name || !strcmp(name, "HEAD"))
1645                ret = current_branch;
1646        else
1647                ret = make_branch(name, 0);
1648        set_merge(ret);
1649        return ret;
1650}
1651
1652int branch_has_merge_config(struct branch *branch)
1653{
1654        return branch && !!branch->merge;
1655}
1656
1657int branch_merge_matches(struct branch *branch,
1658                                 int i,
1659                                 const char *refname)
1660{
1661        if (!branch || i < 0 || i >= branch->merge_nr)
1662                return 0;
1663        return refname_match(branch->merge[i]->src, refname);
1664}
1665
1666__attribute__((format (printf,2,3)))
1667static const char *error_buf(struct strbuf *err, const char *fmt, ...)
1668{
1669        if (err) {
1670                va_list ap;
1671                va_start(ap, fmt);
1672                strbuf_vaddf(err, fmt, ap);
1673                va_end(ap);
1674        }
1675        return NULL;
1676}
1677
1678const char *branch_get_upstream(struct branch *branch, struct strbuf *err)
1679{
1680        if (!branch)
1681                return error_buf(err, _("HEAD does not point to a branch"));
1682
1683        if (!branch->merge || !branch->merge[0]) {
1684                /*
1685                 * no merge config; is it because the user didn't define any,
1686                 * or because it is not a real branch, and get_branch
1687                 * auto-vivified it?
1688                 */
1689                if (!ref_exists(branch->refname))
1690                        return error_buf(err, _("no such branch: '%s'"),
1691                                         branch->name);
1692                return error_buf(err,
1693                                 _("no upstream configured for branch '%s'"),
1694                                 branch->name);
1695        }
1696
1697        if (!branch->merge[0]->dst)
1698                return error_buf(err,
1699                                 _("upstream branch '%s' not stored as a remote-tracking branch"),
1700                                 branch->merge[0]->src);
1701
1702        return branch->merge[0]->dst;
1703}
1704
1705static const char *tracking_for_push_dest(struct remote *remote,
1706                                          const char *refname,
1707                                          struct strbuf *err)
1708{
1709        char *ret;
1710
1711        ret = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
1712        if (!ret)
1713                return error_buf(err,
1714                                 _("push destination '%s' on remote '%s' has no local tracking branch"),
1715                                 refname, remote->name);
1716        return ret;
1717}
1718
1719static const char *branch_get_push_1(struct branch *branch, struct strbuf *err)
1720{
1721        struct remote *remote;
1722
1723        remote = remote_get(pushremote_for_branch(branch, NULL));
1724        if (!remote)
1725                return error_buf(err,
1726                                 _("branch '%s' has no remote for pushing"),
1727                                 branch->name);
1728
1729        if (remote->push_refspec_nr) {
1730                char *dst;
1731                const char *ret;
1732
1733                dst = apply_refspecs(remote->push, remote->push_refspec_nr,
1734                                     branch->refname);
1735                if (!dst)
1736                        return error_buf(err,
1737                                         _("push refspecs for '%s' do not include '%s'"),
1738                                         remote->name, branch->name);
1739
1740                ret = tracking_for_push_dest(remote, dst, err);
1741                free(dst);
1742                return ret;
1743        }
1744
1745        if (remote->mirror)
1746                return tracking_for_push_dest(remote, branch->refname, err);
1747
1748        switch (push_default) {
1749        case PUSH_DEFAULT_NOTHING:
1750                return error_buf(err, _("push has no destination (push.default is 'nothing')"));
1751
1752        case PUSH_DEFAULT_MATCHING:
1753        case PUSH_DEFAULT_CURRENT:
1754                return tracking_for_push_dest(remote, branch->refname, err);
1755
1756        case PUSH_DEFAULT_UPSTREAM:
1757                return branch_get_upstream(branch, err);
1758
1759        case PUSH_DEFAULT_UNSPECIFIED:
1760        case PUSH_DEFAULT_SIMPLE:
1761                {
1762                        const char *up, *cur;
1763
1764                        up = branch_get_upstream(branch, err);
1765                        if (!up)
1766                                return NULL;
1767                        cur = tracking_for_push_dest(remote, branch->refname, err);
1768                        if (!cur)
1769                                return NULL;
1770                        if (strcmp(cur, up))
1771                                return error_buf(err,
1772                                                 _("cannot resolve 'simple' push to a single destination"));
1773                        return cur;
1774                }
1775        }
1776
1777        die("BUG: unhandled push situation");
1778}
1779
1780const char *branch_get_push(struct branch *branch, struct strbuf *err)
1781{
1782        if (!branch)
1783                return error_buf(err, _("HEAD does not point to a branch"));
1784
1785        if (!branch->push_tracking_ref)
1786                branch->push_tracking_ref = branch_get_push_1(branch, err);
1787        return branch->push_tracking_ref;
1788}
1789
1790static int ignore_symref_update(const char *refname)
1791{
1792        int flag;
1793
1794        if (!resolve_ref_unsafe(refname, 0, NULL, &flag))
1795                return 0; /* non-existing refs are OK */
1796        return (flag & REF_ISSYMREF);
1797}
1798
1799/*
1800 * Create and return a list of (struct ref) consisting of copies of
1801 * each remote_ref that matches refspec.  refspec must be a pattern.
1802 * Fill in the copies' peer_ref to describe the local tracking refs to
1803 * which they map.  Omit any references that would map to an existing
1804 * local symbolic ref.
1805 */
1806static struct ref *get_expanded_map(const struct ref *remote_refs,
1807                                    const struct refspec *refspec)
1808{
1809        const struct ref *ref;
1810        struct ref *ret = NULL;
1811        struct ref **tail = &ret;
1812
1813        for (ref = remote_refs; ref; ref = ref->next) {
1814                char *expn_name = NULL;
1815
1816                if (strchr(ref->name, '^'))
1817                        continue; /* a dereference item */
1818                if (match_name_with_pattern(refspec->src, ref->name,
1819                                            refspec->dst, &expn_name) &&
1820                    !ignore_symref_update(expn_name)) {
1821                        struct ref *cpy = copy_ref(ref);
1822
1823                        cpy->peer_ref = alloc_ref(expn_name);
1824                        if (refspec->force)
1825                                cpy->peer_ref->force = 1;
1826                        *tail = cpy;
1827                        tail = &cpy->next;
1828                }
1829                free(expn_name);
1830        }
1831
1832        return ret;
1833}
1834
1835static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1836{
1837        const struct ref *ref;
1838        for (ref = refs; ref; ref = ref->next) {
1839                if (refname_match(name, ref->name))
1840                        return ref;
1841        }
1842        return NULL;
1843}
1844
1845struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1846{
1847        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1848
1849        if (!ref)
1850                return NULL;
1851
1852        return copy_ref(ref);
1853}
1854
1855static struct ref *get_local_ref(const char *name)
1856{
1857        if (!name || name[0] == '\0')
1858                return NULL;
1859
1860        if (starts_with(name, "refs/"))
1861                return alloc_ref(name);
1862
1863        if (starts_with(name, "heads/") ||
1864            starts_with(name, "tags/") ||
1865            starts_with(name, "remotes/"))
1866                return alloc_ref_with_prefix("refs/", 5, name);
1867
1868        return alloc_ref_with_prefix("refs/heads/", 11, name);
1869}
1870
1871int get_fetch_map(const struct ref *remote_refs,
1872                  const struct refspec *refspec,
1873                  struct ref ***tail,
1874                  int missing_ok)
1875{
1876        struct ref *ref_map, **rmp;
1877
1878        if (refspec->pattern) {
1879                ref_map = get_expanded_map(remote_refs, refspec);
1880        } else {
1881                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1882
1883                if (refspec->exact_sha1) {
1884                        ref_map = alloc_ref(name);
1885                        get_oid_hex(name, &ref_map->old_oid);
1886                } else {
1887                        ref_map = get_remote_ref(remote_refs, name);
1888                }
1889                if (!missing_ok && !ref_map)
1890                        die("Couldn't find remote ref %s", name);
1891                if (ref_map) {
1892                        ref_map->peer_ref = get_local_ref(refspec->dst);
1893                        if (ref_map->peer_ref && refspec->force)
1894                                ref_map->peer_ref->force = 1;
1895                }
1896        }
1897
1898        for (rmp = &ref_map; *rmp; ) {
1899                if ((*rmp)->peer_ref) {
1900                        if (!starts_with((*rmp)->peer_ref->name, "refs/") ||
1901                            check_refname_format((*rmp)->peer_ref->name, 0)) {
1902                                struct ref *ignore = *rmp;
1903                                error("* Ignoring funny ref '%s' locally",
1904                                      (*rmp)->peer_ref->name);
1905                                *rmp = (*rmp)->next;
1906                                free(ignore->peer_ref);
1907                                free(ignore);
1908                                continue;
1909                        }
1910                }
1911                rmp = &((*rmp)->next);
1912        }
1913
1914        if (ref_map)
1915                tail_link_ref(ref_map, tail);
1916
1917        return 0;
1918}
1919
1920int resolve_remote_symref(struct ref *ref, struct ref *list)
1921{
1922        if (!ref->symref)
1923                return 0;
1924        for (; list; list = list->next)
1925                if (!strcmp(ref->symref, list->name)) {
1926                        oidcpy(&ref->old_oid, &list->old_oid);
1927                        return 0;
1928                }
1929        return 1;
1930}
1931
1932static void unmark_and_free(struct commit_list *list, unsigned int mark)
1933{
1934        while (list) {
1935                struct commit *commit = pop_commit(&list);
1936                commit->object.flags &= ~mark;
1937        }
1938}
1939
1940int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid)
1941{
1942        struct object *o;
1943        struct commit *old, *new;
1944        struct commit_list *list, *used;
1945        int found = 0;
1946
1947        /*
1948         * Both new and old must be commit-ish and new is descendant of
1949         * old.  Otherwise we require --force.
1950         */
1951        o = deref_tag(parse_object(old_oid), NULL, 0);
1952        if (!o || o->type != OBJ_COMMIT)
1953                return 0;
1954        old = (struct commit *) o;
1955
1956        o = deref_tag(parse_object(new_oid), NULL, 0);
1957        if (!o || o->type != OBJ_COMMIT)
1958                return 0;
1959        new = (struct commit *) o;
1960
1961        if (parse_commit(new) < 0)
1962                return 0;
1963
1964        used = list = NULL;
1965        commit_list_insert(new, &list);
1966        while (list) {
1967                new = pop_most_recent_commit(&list, TMP_MARK);
1968                commit_list_insert(new, &used);
1969                if (new == old) {
1970                        found = 1;
1971                        break;
1972                }
1973        }
1974        unmark_and_free(list, TMP_MARK);
1975        unmark_and_free(used, TMP_MARK);
1976        return found;
1977}
1978
1979/*
1980 * Compare a branch with its upstream, and save their differences (number
1981 * of commits) in *num_ours and *num_theirs. The name of the upstream branch
1982 * (or NULL if no upstream is defined) is returned via *upstream_name, if it
1983 * is not itself NULL.
1984 *
1985 * Returns -1 if num_ours and num_theirs could not be filled in (e.g., no
1986 * upstream defined, or ref does not exist), 0 otherwise.
1987 */
1988int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs,
1989                       const char **upstream_name)
1990{
1991        struct object_id oid;
1992        struct commit *ours, *theirs;
1993        struct rev_info revs;
1994        const char *base;
1995        struct argv_array argv = ARGV_ARRAY_INIT;
1996
1997        /* Cannot stat unless we are marked to build on top of somebody else. */
1998        base = branch_get_upstream(branch, NULL);
1999        if (upstream_name)
2000                *upstream_name = base;
2001        if (!base)
2002                return -1;
2003
2004        /* Cannot stat if what we used to build on no longer exists */
2005        if (read_ref(base, &oid))
2006                return -1;
2007        theirs = lookup_commit_reference(&oid);
2008        if (!theirs)
2009                return -1;
2010
2011        if (read_ref(branch->refname, &oid))
2012                return -1;
2013        ours = lookup_commit_reference(&oid);
2014        if (!ours)
2015                return -1;
2016
2017        /* are we the same? */
2018        if (theirs == ours) {
2019                *num_theirs = *num_ours = 0;
2020                return 0;
2021        }
2022
2023        /* Run "rev-list --left-right ours...theirs" internally... */
2024        argv_array_push(&argv, ""); /* ignored */
2025        argv_array_push(&argv, "--left-right");
2026        argv_array_pushf(&argv, "%s...%s",
2027                         oid_to_hex(&ours->object.oid),
2028                         oid_to_hex(&theirs->object.oid));
2029        argv_array_push(&argv, "--");
2030
2031        init_revisions(&revs, NULL);
2032        setup_revisions(argv.argc, argv.argv, &revs, NULL);
2033        if (prepare_revision_walk(&revs))
2034                die("revision walk setup failed");
2035
2036        /* ... and count the commits on each side. */
2037        *num_ours = 0;
2038        *num_theirs = 0;
2039        while (1) {
2040                struct commit *c = get_revision(&revs);
2041                if (!c)
2042                        break;
2043                if (c->object.flags & SYMMETRIC_LEFT)
2044                        (*num_ours)++;
2045                else
2046                        (*num_theirs)++;
2047        }
2048
2049        /* clear object flags smudged by the above traversal */
2050        clear_commit_marks(ours, ALL_REV_FLAGS);
2051        clear_commit_marks(theirs, ALL_REV_FLAGS);
2052
2053        argv_array_clear(&argv);
2054        return 0;
2055}
2056
2057/*
2058 * Return true when there is anything to report, otherwise false.
2059 */
2060int format_tracking_info(struct branch *branch, struct strbuf *sb)
2061{
2062        int ours, theirs;
2063        const char *full_base;
2064        char *base;
2065        int upstream_is_gone = 0;
2066
2067        if (stat_tracking_info(branch, &ours, &theirs, &full_base) < 0) {
2068                if (!full_base)
2069                        return 0;
2070                upstream_is_gone = 1;
2071        }
2072
2073        base = shorten_unambiguous_ref(full_base, 0);
2074        if (upstream_is_gone) {
2075                strbuf_addf(sb,
2076                        _("Your branch is based on '%s', but the upstream is gone.\n"),
2077                        base);
2078                if (advice_status_hints)
2079                        strbuf_addstr(sb,
2080                                _("  (use \"git branch --unset-upstream\" to fixup)\n"));
2081        } else if (!ours && !theirs) {
2082                strbuf_addf(sb,
2083                        _("Your branch is up to date with '%s'.\n"),
2084                        base);
2085        } else if (!theirs) {
2086                strbuf_addf(sb,
2087                        Q_("Your branch is ahead of '%s' by %d commit.\n",
2088                           "Your branch is ahead of '%s' by %d commits.\n",
2089                           ours),
2090                        base, ours);
2091                if (advice_status_hints)
2092                        strbuf_addstr(sb,
2093                                _("  (use \"git push\" to publish your local commits)\n"));
2094        } else if (!ours) {
2095                strbuf_addf(sb,
2096                        Q_("Your branch is behind '%s' by %d commit, "
2097                               "and can be fast-forwarded.\n",
2098                           "Your branch is behind '%s' by %d commits, "
2099                               "and can be fast-forwarded.\n",
2100                           theirs),
2101                        base, theirs);
2102                if (advice_status_hints)
2103                        strbuf_addstr(sb,
2104                                _("  (use \"git pull\" to update your local branch)\n"));
2105        } else {
2106                strbuf_addf(sb,
2107                        Q_("Your branch and '%s' have diverged,\n"
2108                               "and have %d and %d different commit each, "
2109                               "respectively.\n",
2110                           "Your branch and '%s' have diverged,\n"
2111                               "and have %d and %d different commits each, "
2112                               "respectively.\n",
2113                           ours + theirs),
2114                        base, ours, theirs);
2115                if (advice_status_hints)
2116                        strbuf_addstr(sb,
2117                                _("  (use \"git pull\" to merge the remote branch into yours)\n"));
2118        }
2119        free(base);
2120        return 1;
2121}
2122
2123static int one_local_ref(const char *refname, const struct object_id *oid,
2124                         int flag, void *cb_data)
2125{
2126        struct ref ***local_tail = cb_data;
2127        struct ref *ref;
2128
2129        /* we already know it starts with refs/ to get here */
2130        if (check_refname_format(refname + 5, 0))
2131                return 0;
2132
2133        ref = alloc_ref(refname);
2134        oidcpy(&ref->new_oid, oid);
2135        **local_tail = ref;
2136        *local_tail = &ref->next;
2137        return 0;
2138}
2139
2140struct ref *get_local_heads(void)
2141{
2142        struct ref *local_refs = NULL, **local_tail = &local_refs;
2143
2144        for_each_ref(one_local_ref, &local_tail);
2145        return local_refs;
2146}
2147
2148struct ref *guess_remote_head(const struct ref *head,
2149                              const struct ref *refs,
2150                              int all)
2151{
2152        const struct ref *r;
2153        struct ref *list = NULL;
2154        struct ref **tail = &list;
2155
2156        if (!head)
2157                return NULL;
2158
2159        /*
2160         * Some transports support directly peeking at
2161         * where HEAD points; if that is the case, then
2162         * we don't have to guess.
2163         */
2164        if (head->symref)
2165                return copy_ref(find_ref_by_name(refs, head->symref));
2166
2167        /* If refs/heads/master could be right, it is. */
2168        if (!all) {
2169                r = find_ref_by_name(refs, "refs/heads/master");
2170                if (r && !oidcmp(&r->old_oid, &head->old_oid))
2171                        return copy_ref(r);
2172        }
2173
2174        /* Look for another ref that points there */
2175        for (r = refs; r; r = r->next) {
2176                if (r != head &&
2177                    starts_with(r->name, "refs/heads/") &&
2178                    !oidcmp(&r->old_oid, &head->old_oid)) {
2179                        *tail = copy_ref(r);
2180                        tail = &((*tail)->next);
2181                        if (!all)
2182                                break;
2183                }
2184        }
2185
2186        return list;
2187}
2188
2189struct stale_heads_info {
2190        struct string_list *ref_names;
2191        struct ref **stale_refs_tail;
2192        struct refspec *refs;
2193        int ref_count;
2194};
2195
2196static int get_stale_heads_cb(const char *refname, const struct object_id *oid,
2197                              int flags, void *cb_data)
2198{
2199        struct stale_heads_info *info = cb_data;
2200        struct string_list matches = STRING_LIST_INIT_DUP;
2201        struct refspec query;
2202        int i, stale = 1;
2203        memset(&query, 0, sizeof(struct refspec));
2204        query.dst = (char *)refname;
2205
2206        query_refspecs_multiple(info->refs, info->ref_count, &query, &matches);
2207        if (matches.nr == 0)
2208                goto clean_exit; /* No matches */
2209
2210        /*
2211         * If we did find a suitable refspec and it's not a symref and
2212         * it's not in the list of refs that currently exist in that
2213         * remote, we consider it to be stale. In order to deal with
2214         * overlapping refspecs, we need to go over all of the
2215         * matching refs.
2216         */
2217        if (flags & REF_ISSYMREF)
2218                goto clean_exit;
2219
2220        for (i = 0; stale && i < matches.nr; i++)
2221                if (string_list_has_string(info->ref_names, matches.items[i].string))
2222                        stale = 0;
2223
2224        if (stale) {
2225                struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
2226                oidcpy(&ref->new_oid, oid);
2227        }
2228
2229clean_exit:
2230        string_list_clear(&matches, 0);
2231        return 0;
2232}
2233
2234struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fetch_map)
2235{
2236        struct ref *ref, *stale_refs = NULL;
2237        struct string_list ref_names = STRING_LIST_INIT_NODUP;
2238        struct stale_heads_info info;
2239
2240        info.ref_names = &ref_names;
2241        info.stale_refs_tail = &stale_refs;
2242        info.refs = refs;
2243        info.ref_count = ref_count;
2244        for (ref = fetch_map; ref; ref = ref->next)
2245                string_list_append(&ref_names, ref->name);
2246        string_list_sort(&ref_names);
2247        for_each_ref(get_stale_heads_cb, &info);
2248        string_list_clear(&ref_names, 0);
2249        return stale_refs;
2250}
2251
2252/*
2253 * Compare-and-swap
2254 */
2255static void clear_cas_option(struct push_cas_option *cas)
2256{
2257        int i;
2258
2259        for (i = 0; i < cas->nr; i++)
2260                free(cas->entry[i].refname);
2261        free(cas->entry);
2262        memset(cas, 0, sizeof(*cas));
2263}
2264
2265static struct push_cas *add_cas_entry(struct push_cas_option *cas,
2266                                      const char *refname,
2267                                      size_t refnamelen)
2268{
2269        struct push_cas *entry;
2270        ALLOC_GROW(cas->entry, cas->nr + 1, cas->alloc);
2271        entry = &cas->entry[cas->nr++];
2272        memset(entry, 0, sizeof(*entry));
2273        entry->refname = xmemdupz(refname, refnamelen);
2274        return entry;
2275}
2276
2277static int parse_push_cas_option(struct push_cas_option *cas, const char *arg, int unset)
2278{
2279        const char *colon;
2280        struct push_cas *entry;
2281
2282        if (unset) {
2283                /* "--no-<option>" */
2284                clear_cas_option(cas);
2285                return 0;
2286        }
2287
2288        if (!arg) {
2289                /* just "--<option>" */
2290                cas->use_tracking_for_rest = 1;
2291                return 0;
2292        }
2293
2294        /* "--<option>=refname" or "--<option>=refname:value" */
2295        colon = strchrnul(arg, ':');
2296        entry = add_cas_entry(cas, arg, colon - arg);
2297        if (!*colon)
2298                entry->use_tracking = 1;
2299        else if (!colon[1])
2300                oidclr(&entry->expect);
2301        else if (get_oid(colon + 1, &entry->expect))
2302                return error("cannot parse expected object name '%s'", colon + 1);
2303        return 0;
2304}
2305
2306int parseopt_push_cas_option(const struct option *opt, const char *arg, int unset)
2307{
2308        return parse_push_cas_option(opt->value, arg, unset);
2309}
2310
2311int is_empty_cas(const struct push_cas_option *cas)
2312{
2313        return !cas->use_tracking_for_rest && !cas->nr;
2314}
2315
2316/*
2317 * Look at remote.fetch refspec and see if we have a remote
2318 * tracking branch for the refname there.  Fill its current
2319 * value in sha1[].
2320 * If we cannot do so, return negative to signal an error.
2321 */
2322static int remote_tracking(struct remote *remote, const char *refname,
2323                           struct object_id *oid)
2324{
2325        char *dst;
2326
2327        dst = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
2328        if (!dst)
2329                return -1; /* no tracking ref for refname at remote */
2330        if (read_ref(dst, oid))
2331                return -1; /* we know what the tracking ref is but we cannot read it */
2332        return 0;
2333}
2334
2335static void apply_cas(struct push_cas_option *cas,
2336                      struct remote *remote,
2337                      struct ref *ref)
2338{
2339        int i;
2340
2341        /* Find an explicit --<option>=<name>[:<value>] entry */
2342        for (i = 0; i < cas->nr; i++) {
2343                struct push_cas *entry = &cas->entry[i];
2344                if (!refname_match(entry->refname, ref->name))
2345                        continue;
2346                ref->expect_old_sha1 = 1;
2347                if (!entry->use_tracking)
2348                        oidcpy(&ref->old_oid_expect, &entry->expect);
2349                else if (remote_tracking(remote, ref->name, &ref->old_oid_expect))
2350                        oidclr(&ref->old_oid_expect);
2351                return;
2352        }
2353
2354        /* Are we using "--<option>" to cover all? */
2355        if (!cas->use_tracking_for_rest)
2356                return;
2357
2358        ref->expect_old_sha1 = 1;
2359        if (remote_tracking(remote, ref->name, &ref->old_oid_expect))
2360                oidclr(&ref->old_oid_expect);
2361}
2362
2363void apply_push_cas(struct push_cas_option *cas,
2364                    struct remote *remote,
2365                    struct ref *remote_refs)
2366{
2367        struct ref *ref;
2368        for (ref = remote_refs; ref; ref = ref->next)
2369                apply_cas(cas, remote, ref);
2370}