remote.con commit Merge branch 'sg/revision-parser-skip-prefix' into maint (8d7a6b6)
   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#include "mergesort.h"
  11#include "argv-array.h"
  12
  13enum map_direction { FROM_SRC, FROM_DST };
  14
  15static struct refspec s_tag_refspec = {
  16        0,
  17        1,
  18        0,
  19        0,
  20        "refs/tags/*",
  21        "refs/tags/*"
  22};
  23
  24const struct refspec *tag_refspec = &s_tag_refspec;
  25
  26struct counted_string {
  27        size_t len;
  28        const char *s;
  29};
  30struct rewrite {
  31        const char *base;
  32        size_t baselen;
  33        struct counted_string *instead_of;
  34        int instead_of_nr;
  35        int instead_of_alloc;
  36};
  37struct rewrites {
  38        struct rewrite **rewrite;
  39        int rewrite_alloc;
  40        int rewrite_nr;
  41};
  42
  43static struct remote **remotes;
  44static int remotes_alloc;
  45static int remotes_nr;
  46static struct hashmap remotes_hash;
  47
  48static struct branch **branches;
  49static int branches_alloc;
  50static int branches_nr;
  51
  52static struct branch *current_branch;
  53static const char *pushremote_name;
  54
  55static struct rewrites rewrites;
  56static struct rewrites rewrites_push;
  57
  58static int valid_remote(const struct remote *remote)
  59{
  60        return (!!remote->url) || (!!remote->foreign_vcs);
  61}
  62
  63static const char *alias_url(const char *url, struct rewrites *r)
  64{
  65        int i, j;
  66        struct counted_string *longest;
  67        int longest_i;
  68
  69        longest = NULL;
  70        longest_i = -1;
  71        for (i = 0; i < r->rewrite_nr; i++) {
  72                if (!r->rewrite[i])
  73                        continue;
  74                for (j = 0; j < r->rewrite[i]->instead_of_nr; j++) {
  75                        if (starts_with(url, r->rewrite[i]->instead_of[j].s) &&
  76                            (!longest ||
  77                             longest->len < r->rewrite[i]->instead_of[j].len)) {
  78                                longest = &(r->rewrite[i]->instead_of[j]);
  79                                longest_i = i;
  80                        }
  81                }
  82        }
  83        if (!longest)
  84                return url;
  85
  86        return xstrfmt("%s%s", r->rewrite[longest_i]->base, url + longest->len);
  87}
  88
  89static void add_push_refspec(struct remote *remote, const char *ref)
  90{
  91        ALLOC_GROW(remote->push_refspec,
  92                   remote->push_refspec_nr + 1,
  93                   remote->push_refspec_alloc);
  94        remote->push_refspec[remote->push_refspec_nr++] = ref;
  95}
  96
  97static void add_fetch_refspec(struct remote *remote, const char *ref)
  98{
  99        ALLOC_GROW(remote->fetch_refspec,
 100                   remote->fetch_refspec_nr + 1,
 101                   remote->fetch_refspec_alloc);
 102        remote->fetch_refspec[remote->fetch_refspec_nr++] = ref;
 103}
 104
 105static void add_url(struct remote *remote, const char *url)
 106{
 107        ALLOC_GROW(remote->url, remote->url_nr + 1, remote->url_alloc);
 108        remote->url[remote->url_nr++] = url;
 109}
 110
 111static void add_pushurl(struct remote *remote, const char *pushurl)
 112{
 113        ALLOC_GROW(remote->pushurl, remote->pushurl_nr + 1, remote->pushurl_alloc);
 114        remote->pushurl[remote->pushurl_nr++] = pushurl;
 115}
 116
 117static void add_pushurl_alias(struct remote *remote, const char *url)
 118{
 119        const char *pushurl = alias_url(url, &rewrites_push);
 120        if (pushurl != url)
 121                add_pushurl(remote, pushurl);
 122}
 123
 124static void add_url_alias(struct remote *remote, const char *url)
 125{
 126        add_url(remote, alias_url(url, &rewrites));
 127        add_pushurl_alias(remote, url);
 128}
 129
 130struct remotes_hash_key {
 131        const char *str;
 132        int len;
 133};
 134
 135static int remotes_hash_cmp(const struct remote *a, const struct remote *b, const struct remotes_hash_key *key)
 136{
 137        if (key)
 138                return strncmp(a->name, key->str, key->len) || a->name[key->len];
 139        else
 140                return strcmp(a->name, b->name);
 141}
 142
 143static inline void init_remotes_hash(void)
 144{
 145        if (!remotes_hash.cmpfn)
 146                hashmap_init(&remotes_hash, (hashmap_cmp_fn)remotes_hash_cmp, 0);
 147}
 148
 149static struct remote *make_remote(const char *name, int len)
 150{
 151        struct remote *ret, *replaced;
 152        struct remotes_hash_key lookup;
 153        struct hashmap_entry lookup_entry;
 154
 155        if (!len)
 156                len = strlen(name);
 157
 158        init_remotes_hash();
 159        lookup.str = name;
 160        lookup.len = len;
 161        hashmap_entry_init(&lookup_entry, memhash(name, len));
 162
 163        if ((ret = hashmap_get(&remotes_hash, &lookup_entry, &lookup)) != NULL)
 164                return ret;
 165
 166        ret = xcalloc(1, sizeof(struct remote));
 167        ret->prune = -1;  /* unspecified */
 168        ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 169        remotes[remotes_nr++] = ret;
 170        ret->name = xstrndup(name, len);
 171
 172        hashmap_entry_init(ret, lookup_entry.hash);
 173        replaced = hashmap_put(&remotes_hash, ret);
 174        assert(replaced == NULL);  /* no previous entry overwritten */
 175        return ret;
 176}
 177
 178static void add_merge(struct branch *branch, const char *name)
 179{
 180        ALLOC_GROW(branch->merge_name, branch->merge_nr + 1,
 181                   branch->merge_alloc);
 182        branch->merge_name[branch->merge_nr++] = name;
 183}
 184
 185static struct branch *make_branch(const char *name, int len)
 186{
 187        struct branch *ret;
 188        int i;
 189
 190        for (i = 0; i < branches_nr; i++) {
 191                if (len ? (!strncmp(name, branches[i]->name, len) &&
 192                           !branches[i]->name[len]) :
 193                    !strcmp(name, branches[i]->name))
 194                        return branches[i];
 195        }
 196
 197        ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 198        ret = xcalloc(1, sizeof(struct branch));
 199        branches[branches_nr++] = ret;
 200        if (len)
 201                ret->name = xstrndup(name, len);
 202        else
 203                ret->name = xstrdup(name);
 204        ret->refname = xstrfmt("refs/heads/%s", ret->name);
 205
 206        return ret;
 207}
 208
 209static struct rewrite *make_rewrite(struct rewrites *r, const char *base, int len)
 210{
 211        struct rewrite *ret;
 212        int i;
 213
 214        for (i = 0; i < r->rewrite_nr; i++) {
 215                if (len
 216                    ? (len == r->rewrite[i]->baselen &&
 217                       !strncmp(base, r->rewrite[i]->base, len))
 218                    : !strcmp(base, r->rewrite[i]->base))
 219                        return r->rewrite[i];
 220        }
 221
 222        ALLOC_GROW(r->rewrite, r->rewrite_nr + 1, r->rewrite_alloc);
 223        ret = xcalloc(1, sizeof(struct rewrite));
 224        r->rewrite[r->rewrite_nr++] = ret;
 225        if (len) {
 226                ret->base = xstrndup(base, len);
 227                ret->baselen = len;
 228        }
 229        else {
 230                ret->base = xstrdup(base);
 231                ret->baselen = strlen(base);
 232        }
 233        return ret;
 234}
 235
 236static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 237{
 238        ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 239        rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 240        rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 241        rewrite->instead_of_nr++;
 242}
 243
 244static const char *skip_spaces(const char *s)
 245{
 246        while (isspace(*s))
 247                s++;
 248        return s;
 249}
 250
 251static void read_remotes_file(struct remote *remote)
 252{
 253        struct strbuf buf = STRBUF_INIT;
 254        FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
 255
 256        if (!f)
 257                return;
 258        remote->configured_in_repo = 1;
 259        remote->origin = REMOTE_REMOTES;
 260        while (strbuf_getline(&buf, f) != EOF) {
 261                const char *v;
 262
 263                strbuf_rtrim(&buf);
 264
 265                if (skip_prefix(buf.buf, "URL:", &v))
 266                        add_url_alias(remote, xstrdup(skip_spaces(v)));
 267                else if (skip_prefix(buf.buf, "Push:", &v))
 268                        add_push_refspec(remote, xstrdup(skip_spaces(v)));
 269                else if (skip_prefix(buf.buf, "Pull:", &v))
 270                        add_fetch_refspec(remote, xstrdup(skip_spaces(v)));
 271        }
 272        strbuf_release(&buf);
 273        fclose(f);
 274}
 275
 276static void read_branches_file(struct remote *remote)
 277{
 278        char *frag;
 279        struct strbuf buf = STRBUF_INIT;
 280        FILE *f = fopen(git_path("branches/%s", remote->name), "r");
 281
 282        if (!f)
 283                return;
 284
 285        strbuf_getline_lf(&buf, f);
 286        fclose(f);
 287        strbuf_trim(&buf);
 288        if (!buf.len) {
 289                strbuf_release(&buf);
 290                return;
 291        }
 292
 293        remote->configured_in_repo = 1;
 294        remote->origin = REMOTE_BRANCHES;
 295
 296        /*
 297         * The branches file would have URL and optionally
 298         * #branch specified.  The "master" (or specified) branch is
 299         * fetched and stored in the local branch matching the
 300         * remote name.
 301         */
 302        frag = strchr(buf.buf, '#');
 303        if (frag)
 304                *(frag++) = '\0';
 305        else
 306                frag = "master";
 307
 308        add_url_alias(remote, strbuf_detach(&buf, NULL));
 309        add_fetch_refspec(remote, xstrfmt("refs/heads/%s:refs/heads/%s",
 310                                          frag, remote->name));
 311
 312        /*
 313         * Cogito compatible push: push current HEAD to remote #branch
 314         * (master if missing)
 315         */
 316        add_push_refspec(remote, xstrfmt("HEAD:refs/heads/%s", frag));
 317        remote->fetch_tags = 1; /* always auto-follow */
 318}
 319
 320static int handle_config(const char *key, const char *value, void *cb)
 321{
 322        const char *name;
 323        int namelen;
 324        const char *subkey;
 325        struct remote *remote;
 326        struct branch *branch;
 327        if (parse_config_key(key, "branch", &name, &namelen, &subkey) >= 0) {
 328                if (!name)
 329                        return 0;
 330                branch = make_branch(name, namelen);
 331                if (!strcmp(subkey, "remote")) {
 332                        return git_config_string(&branch->remote_name, key, value);
 333                } else if (!strcmp(subkey, "pushremote")) {
 334                        return git_config_string(&branch->pushremote_name, key, value);
 335                } else if (!strcmp(subkey, "merge")) {
 336                        if (!value)
 337                                return config_error_nonbool(key);
 338                        add_merge(branch, xstrdup(value));
 339                }
 340                return 0;
 341        }
 342        if (parse_config_key(key, "url", &name, &namelen, &subkey) >= 0) {
 343                struct rewrite *rewrite;
 344                if (!name)
 345                        return 0;
 346                if (!strcmp(subkey, "insteadof")) {
 347                        rewrite = make_rewrite(&rewrites, name, namelen);
 348                        if (!value)
 349                                return config_error_nonbool(key);
 350                        add_instead_of(rewrite, xstrdup(value));
 351                } else if (!strcmp(subkey, "pushinsteadof")) {
 352                        rewrite = make_rewrite(&rewrites_push, name, namelen);
 353                        if (!value)
 354                                return config_error_nonbool(key);
 355                        add_instead_of(rewrite, xstrdup(value));
 356                }
 357        }
 358
 359        if (parse_config_key(key, "remote", &name, &namelen, &subkey) < 0)
 360                return 0;
 361
 362        /* Handle remote.* variables */
 363        if (!name && !strcmp(subkey, "pushdefault"))
 364                return git_config_string(&pushremote_name, key, value);
 365
 366        if (!name)
 367                return 0;
 368        /* Handle remote.<name>.* variables */
 369        if (*name == '/') {
 370                warning("Config remote shorthand cannot begin with '/': %s",
 371                        name);
 372                return 0;
 373        }
 374        remote = make_remote(name, namelen);
 375        remote->origin = REMOTE_CONFIG;
 376        if (current_config_scope() == CONFIG_SCOPE_REPO)
 377                remote->configured_in_repo = 1;
 378        if (!strcmp(subkey, "mirror"))
 379                remote->mirror = git_config_bool(key, value);
 380        else if (!strcmp(subkey, "skipdefaultupdate"))
 381                remote->skip_default_update = git_config_bool(key, value);
 382        else if (!strcmp(subkey, "skipfetchall"))
 383                remote->skip_default_update = git_config_bool(key, value);
 384        else if (!strcmp(subkey, "prune"))
 385                remote->prune = git_config_bool(key, value);
 386        else if (!strcmp(subkey, "url")) {
 387                const char *v;
 388                if (git_config_string(&v, key, value))
 389                        return -1;
 390                add_url(remote, v);
 391        } else if (!strcmp(subkey, "pushurl")) {
 392                const char *v;
 393                if (git_config_string(&v, key, value))
 394                        return -1;
 395                add_pushurl(remote, v);
 396        } else if (!strcmp(subkey, "push")) {
 397                const char *v;
 398                if (git_config_string(&v, key, value))
 399                        return -1;
 400                add_push_refspec(remote, v);
 401        } else if (!strcmp(subkey, "fetch")) {
 402                const char *v;
 403                if (git_config_string(&v, key, value))
 404                        return -1;
 405                add_fetch_refspec(remote, v);
 406        } else if (!strcmp(subkey, "receivepack")) {
 407                const char *v;
 408                if (git_config_string(&v, key, value))
 409                        return -1;
 410                if (!remote->receivepack)
 411                        remote->receivepack = v;
 412                else
 413                        error("more than one receivepack given, using the first");
 414        } else if (!strcmp(subkey, "uploadpack")) {
 415                const char *v;
 416                if (git_config_string(&v, key, value))
 417                        return -1;
 418                if (!remote->uploadpack)
 419                        remote->uploadpack = v;
 420                else
 421                        error("more than one uploadpack given, using the first");
 422        } else if (!strcmp(subkey, "tagopt")) {
 423                if (!strcmp(value, "--no-tags"))
 424                        remote->fetch_tags = -1;
 425                else if (!strcmp(value, "--tags"))
 426                        remote->fetch_tags = 2;
 427        } else if (!strcmp(subkey, "proxy")) {
 428                return git_config_string((const char **)&remote->http_proxy,
 429                                         key, value);
 430        } else if (!strcmp(subkey, "proxyauthmethod")) {
 431                return git_config_string((const char **)&remote->http_proxy_authmethod,
 432                                         key, value);
 433        } else if (!strcmp(subkey, "vcs")) {
 434                return git_config_string(&remote->foreign_vcs, key, value);
 435        }
 436        return 0;
 437}
 438
 439static void alias_all_urls(void)
 440{
 441        int i, j;
 442        for (i = 0; i < remotes_nr; i++) {
 443                int add_pushurl_aliases;
 444                if (!remotes[i])
 445                        continue;
 446                for (j = 0; j < remotes[i]->pushurl_nr; j++) {
 447                        remotes[i]->pushurl[j] = alias_url(remotes[i]->pushurl[j], &rewrites);
 448                }
 449                add_pushurl_aliases = remotes[i]->pushurl_nr == 0;
 450                for (j = 0; j < remotes[i]->url_nr; j++) {
 451                        if (add_pushurl_aliases)
 452                                add_pushurl_alias(remotes[i], remotes[i]->url[j]);
 453                        remotes[i]->url[j] = alias_url(remotes[i]->url[j], &rewrites);
 454                }
 455        }
 456}
 457
 458static void read_config(void)
 459{
 460        static int loaded;
 461        struct object_id oid;
 462        int flag;
 463
 464        if (loaded)
 465                return;
 466        loaded = 1;
 467
 468        current_branch = NULL;
 469        if (startup_info->have_repository) {
 470                const char *head_ref = resolve_ref_unsafe("HEAD", 0, oid.hash, &flag);
 471                if (head_ref && (flag & REF_ISSYMREF) &&
 472                    skip_prefix(head_ref, "refs/heads/", &head_ref)) {
 473                        current_branch = make_branch(head_ref, 0);
 474                }
 475        }
 476        git_config(handle_config, NULL);
 477        alias_all_urls();
 478}
 479
 480static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 481{
 482        int i;
 483        struct refspec *rs = xcalloc(nr_refspec, sizeof(*rs));
 484
 485        for (i = 0; i < nr_refspec; i++) {
 486                size_t llen;
 487                int is_glob;
 488                const char *lhs, *rhs;
 489                int flags;
 490
 491                is_glob = 0;
 492
 493                lhs = refspec[i];
 494                if (*lhs == '+') {
 495                        rs[i].force = 1;
 496                        lhs++;
 497                }
 498
 499                rhs = strrchr(lhs, ':');
 500
 501                /*
 502                 * Before going on, special case ":" (or "+:") as a refspec
 503                 * for pushing matching refs.
 504                 */
 505                if (!fetch && rhs == lhs && rhs[1] == '\0') {
 506                        rs[i].matching = 1;
 507                        continue;
 508                }
 509
 510                if (rhs) {
 511                        size_t rlen = strlen(++rhs);
 512                        is_glob = (1 <= rlen && strchr(rhs, '*'));
 513                        rs[i].dst = xstrndup(rhs, rlen);
 514                }
 515
 516                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 517                if (1 <= llen && memchr(lhs, '*', llen)) {
 518                        if ((rhs && !is_glob) || (!rhs && fetch))
 519                                goto invalid;
 520                        is_glob = 1;
 521                } else if (rhs && is_glob) {
 522                        goto invalid;
 523                }
 524
 525                rs[i].pattern = is_glob;
 526                rs[i].src = xstrndup(lhs, llen);
 527                flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 528
 529                if (fetch) {
 530                        struct object_id unused;
 531
 532                        /* LHS */
 533                        if (!*rs[i].src)
 534                                ; /* empty is ok; it means "HEAD" */
 535                        else if (llen == GIT_SHA1_HEXSZ && !get_oid_hex(rs[i].src, &unused))
 536                                rs[i].exact_sha1 = 1; /* ok */
 537                        else if (!check_refname_format(rs[i].src, flags))
 538                                ; /* valid looking ref is ok */
 539                        else
 540                                goto invalid;
 541                        /* RHS */
 542                        if (!rs[i].dst)
 543                                ; /* missing is ok; it is the same as empty */
 544                        else if (!*rs[i].dst)
 545                                ; /* empty is ok; it means "do not store" */
 546                        else if (!check_refname_format(rs[i].dst, flags))
 547                                ; /* valid looking ref is ok */
 548                        else
 549                                goto invalid;
 550                } else {
 551                        /*
 552                         * LHS
 553                         * - empty is allowed; it means delete.
 554                         * - when wildcarded, it must be a valid looking ref.
 555                         * - otherwise, it must be an extended SHA-1, but
 556                         *   there is no existing way to validate this.
 557                         */
 558                        if (!*rs[i].src)
 559                                ; /* empty is ok */
 560                        else if (is_glob) {
 561                                if (check_refname_format(rs[i].src, flags))
 562                                        goto invalid;
 563                        }
 564                        else
 565                                ; /* anything goes, for now */
 566                        /*
 567                         * RHS
 568                         * - missing is allowed, but LHS then must be a
 569                         *   valid looking ref.
 570                         * - empty is not allowed.
 571                         * - otherwise it must be a valid looking ref.
 572                         */
 573                        if (!rs[i].dst) {
 574                                if (check_refname_format(rs[i].src, flags))
 575                                        goto invalid;
 576                        } else if (!*rs[i].dst) {
 577                                goto invalid;
 578                        } else {
 579                                if (check_refname_format(rs[i].dst, flags))
 580                                        goto invalid;
 581                        }
 582                }
 583        }
 584        return rs;
 585
 586 invalid:
 587        if (verify) {
 588                /*
 589                 * nr_refspec must be greater than zero and i must be valid
 590                 * since it is only possible to reach this point from within
 591                 * the for loop above.
 592                 */
 593                free_refspec(i+1, rs);
 594                return NULL;
 595        }
 596        die("Invalid refspec '%s'", refspec[i]);
 597}
 598
 599int valid_fetch_refspec(const char *fetch_refspec_str)
 600{
 601        struct refspec *refspec;
 602
 603        refspec = parse_refspec_internal(1, &fetch_refspec_str, 1, 1);
 604        free_refspec(1, refspec);
 605        return !!refspec;
 606}
 607
 608struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 609{
 610        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 611}
 612
 613struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 614{
 615        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 616}
 617
 618void free_refspec(int nr_refspec, struct refspec *refspec)
 619{
 620        int i;
 621
 622        if (!refspec)
 623                return;
 624
 625        for (i = 0; i < nr_refspec; i++) {
 626                free(refspec[i].src);
 627                free(refspec[i].dst);
 628        }
 629        free(refspec);
 630}
 631
 632static int valid_remote_nick(const char *name)
 633{
 634        if (!name[0] || is_dot_or_dotdot(name))
 635                return 0;
 636
 637        /* remote nicknames cannot contain slashes */
 638        while (*name)
 639                if (is_dir_sep(*name++))
 640                        return 0;
 641        return 1;
 642}
 643
 644const char *remote_for_branch(struct branch *branch, int *explicit)
 645{
 646        if (branch && branch->remote_name) {
 647                if (explicit)
 648                        *explicit = 1;
 649                return branch->remote_name;
 650        }
 651        if (explicit)
 652                *explicit = 0;
 653        return "origin";
 654}
 655
 656const char *pushremote_for_branch(struct branch *branch, int *explicit)
 657{
 658        if (branch && branch->pushremote_name) {
 659                if (explicit)
 660                        *explicit = 1;
 661                return branch->pushremote_name;
 662        }
 663        if (pushremote_name) {
 664                if (explicit)
 665                        *explicit = 1;
 666                return pushremote_name;
 667        }
 668        return remote_for_branch(branch, explicit);
 669}
 670
 671static struct remote *remote_get_1(const char *name,
 672                                   const char *(*get_default)(struct branch *, int *))
 673{
 674        struct remote *ret;
 675        int name_given = 0;
 676
 677        read_config();
 678
 679        if (name)
 680                name_given = 1;
 681        else
 682                name = get_default(current_branch, &name_given);
 683
 684        ret = make_remote(name, 0);
 685        if (valid_remote_nick(name) && have_git_dir()) {
 686                if (!valid_remote(ret))
 687                        read_remotes_file(ret);
 688                if (!valid_remote(ret))
 689                        read_branches_file(ret);
 690        }
 691        if (name_given && !valid_remote(ret))
 692                add_url_alias(ret, name);
 693        if (!valid_remote(ret))
 694                return NULL;
 695        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 696        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 697        return ret;
 698}
 699
 700struct remote *remote_get(const char *name)
 701{
 702        return remote_get_1(name, remote_for_branch);
 703}
 704
 705struct remote *pushremote_get(const char *name)
 706{
 707        return remote_get_1(name, pushremote_for_branch);
 708}
 709
 710int remote_is_configured(struct remote *remote, int in_repo)
 711{
 712        if (!remote)
 713                return 0;
 714        if (in_repo)
 715                return remote->configured_in_repo;
 716        return !!remote->origin;
 717}
 718
 719int for_each_remote(each_remote_fn fn, void *priv)
 720{
 721        int i, result = 0;
 722        read_config();
 723        for (i = 0; i < remotes_nr && !result; i++) {
 724                struct remote *r = remotes[i];
 725                if (!r)
 726                        continue;
 727                if (!r->fetch)
 728                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 729                                                       r->fetch_refspec);
 730                if (!r->push)
 731                        r->push = parse_push_refspec(r->push_refspec_nr,
 732                                                     r->push_refspec);
 733                result = fn(r, priv);
 734        }
 735        return result;
 736}
 737
 738static void handle_duplicate(struct ref *ref1, struct ref *ref2)
 739{
 740        if (strcmp(ref1->name, ref2->name)) {
 741                if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 742                    ref2->fetch_head_status != FETCH_HEAD_IGNORE) {
 743                        die(_("Cannot fetch both %s and %s to %s"),
 744                            ref1->name, ref2->name, ref2->peer_ref->name);
 745                } else if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 746                           ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 747                        warning(_("%s usually tracks %s, not %s"),
 748                                ref2->peer_ref->name, ref2->name, ref1->name);
 749                } else if (ref1->fetch_head_status == FETCH_HEAD_IGNORE &&
 750                           ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 751                        die(_("%s tracks both %s and %s"),
 752                            ref2->peer_ref->name, ref1->name, ref2->name);
 753                } else {
 754                        /*
 755                         * This last possibility doesn't occur because
 756                         * FETCH_HEAD_IGNORE entries always appear at
 757                         * the end of the list.
 758                         */
 759                        die(_("Internal error"));
 760                }
 761        }
 762        free(ref2->peer_ref);
 763        free(ref2);
 764}
 765
 766struct ref *ref_remove_duplicates(struct ref *ref_map)
 767{
 768        struct string_list refs = STRING_LIST_INIT_NODUP;
 769        struct ref *retval = NULL;
 770        struct ref **p = &retval;
 771
 772        while (ref_map) {
 773                struct ref *ref = ref_map;
 774
 775                ref_map = ref_map->next;
 776                ref->next = NULL;
 777
 778                if (!ref->peer_ref) {
 779                        *p = ref;
 780                        p = &ref->next;
 781                } else {
 782                        struct string_list_item *item =
 783                                string_list_insert(&refs, ref->peer_ref->name);
 784
 785                        if (item->util) {
 786                                /* Entry already existed */
 787                                handle_duplicate((struct ref *)item->util, ref);
 788                        } else {
 789                                *p = ref;
 790                                p = &ref->next;
 791                                item->util = ref;
 792                        }
 793                }
 794        }
 795
 796        string_list_clear(&refs, 0);
 797        return retval;
 798}
 799
 800int remote_has_url(struct remote *remote, const char *url)
 801{
 802        int i;
 803        for (i = 0; i < remote->url_nr; i++) {
 804                if (!strcmp(remote->url[i], url))
 805                        return 1;
 806        }
 807        return 0;
 808}
 809
 810static int match_name_with_pattern(const char *key, const char *name,
 811                                   const char *value, char **result)
 812{
 813        const char *kstar = strchr(key, '*');
 814        size_t klen;
 815        size_t ksuffixlen;
 816        size_t namelen;
 817        int ret;
 818        if (!kstar)
 819                die("Key '%s' of pattern had no '*'", key);
 820        klen = kstar - key;
 821        ksuffixlen = strlen(kstar + 1);
 822        namelen = strlen(name);
 823        ret = !strncmp(name, key, klen) && namelen >= klen + ksuffixlen &&
 824                !memcmp(name + namelen - ksuffixlen, kstar + 1, ksuffixlen);
 825        if (ret && value) {
 826                struct strbuf sb = STRBUF_INIT;
 827                const char *vstar = strchr(value, '*');
 828                if (!vstar)
 829                        die("Value '%s' of pattern has no '*'", value);
 830                strbuf_add(&sb, value, vstar - value);
 831                strbuf_add(&sb, name + klen, namelen - klen - ksuffixlen);
 832                strbuf_addstr(&sb, vstar + 1);
 833                *result = strbuf_detach(&sb, NULL);
 834        }
 835        return ret;
 836}
 837
 838static void query_refspecs_multiple(struct refspec *refs, int ref_count, struct refspec *query, struct string_list *results)
 839{
 840        int i;
 841        int find_src = !query->src;
 842
 843        if (find_src && !query->dst)
 844                error("query_refspecs_multiple: need either src or dst");
 845
 846        for (i = 0; i < ref_count; i++) {
 847                struct refspec *refspec = &refs[i];
 848                const char *key = find_src ? refspec->dst : refspec->src;
 849                const char *value = find_src ? refspec->src : refspec->dst;
 850                const char *needle = find_src ? query->dst : query->src;
 851                char **result = find_src ? &query->src : &query->dst;
 852
 853                if (!refspec->dst)
 854                        continue;
 855                if (refspec->pattern) {
 856                        if (match_name_with_pattern(key, needle, value, result))
 857                                string_list_append_nodup(results, *result);
 858                } else if (!strcmp(needle, key)) {
 859                        string_list_append(results, value);
 860                }
 861        }
 862}
 863
 864int query_refspecs(struct refspec *refs, int ref_count, struct refspec *query)
 865{
 866        int i;
 867        int find_src = !query->src;
 868        const char *needle = find_src ? query->dst : query->src;
 869        char **result = find_src ? &query->src : &query->dst;
 870
 871        if (find_src && !query->dst)
 872                return error("query_refspecs: need either src or dst");
 873
 874        for (i = 0; i < ref_count; i++) {
 875                struct refspec *refspec = &refs[i];
 876                const char *key = find_src ? refspec->dst : refspec->src;
 877                const char *value = find_src ? refspec->src : refspec->dst;
 878
 879                if (!refspec->dst)
 880                        continue;
 881                if (refspec->pattern) {
 882                        if (match_name_with_pattern(key, needle, value, result)) {
 883                                query->force = refspec->force;
 884                                return 0;
 885                        }
 886                } else if (!strcmp(needle, key)) {
 887                        *result = xstrdup(value);
 888                        query->force = refspec->force;
 889                        return 0;
 890                }
 891        }
 892        return -1;
 893}
 894
 895char *apply_refspecs(struct refspec *refspecs, int nr_refspec,
 896                     const char *name)
 897{
 898        struct refspec query;
 899
 900        memset(&query, 0, sizeof(struct refspec));
 901        query.src = (char *)name;
 902
 903        if (query_refspecs(refspecs, nr_refspec, &query))
 904                return NULL;
 905
 906        return query.dst;
 907}
 908
 909int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 910{
 911        return query_refspecs(remote->fetch, remote->fetch_refspec_nr, refspec);
 912}
 913
 914static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 915                const char *name)
 916{
 917        size_t len = strlen(name);
 918        struct ref *ref = xcalloc(1, st_add4(sizeof(*ref), prefixlen, len, 1));
 919        memcpy(ref->name, prefix, prefixlen);
 920        memcpy(ref->name + prefixlen, name, len);
 921        return ref;
 922}
 923
 924struct ref *alloc_ref(const char *name)
 925{
 926        return alloc_ref_with_prefix("", 0, name);
 927}
 928
 929struct ref *copy_ref(const struct ref *ref)
 930{
 931        struct ref *cpy;
 932        size_t len;
 933        if (!ref)
 934                return NULL;
 935        len = st_add3(sizeof(struct ref), strlen(ref->name), 1);
 936        cpy = xmalloc(len);
 937        memcpy(cpy, ref, len);
 938        cpy->next = NULL;
 939        cpy->symref = xstrdup_or_null(ref->symref);
 940        cpy->remote_status = xstrdup_or_null(ref->remote_status);
 941        cpy->peer_ref = copy_ref(ref->peer_ref);
 942        return cpy;
 943}
 944
 945struct ref *copy_ref_list(const struct ref *ref)
 946{
 947        struct ref *ret = NULL;
 948        struct ref **tail = &ret;
 949        while (ref) {
 950                *tail = copy_ref(ref);
 951                ref = ref->next;
 952                tail = &((*tail)->next);
 953        }
 954        return ret;
 955}
 956
 957static void free_ref(struct ref *ref)
 958{
 959        if (!ref)
 960                return;
 961        free_ref(ref->peer_ref);
 962        free(ref->remote_status);
 963        free(ref->symref);
 964        free(ref);
 965}
 966
 967void free_refs(struct ref *ref)
 968{
 969        struct ref *next;
 970        while (ref) {
 971                next = ref->next;
 972                free_ref(ref);
 973                ref = next;
 974        }
 975}
 976
 977int ref_compare_name(const void *va, const void *vb)
 978{
 979        const struct ref *a = va, *b = vb;
 980        return strcmp(a->name, b->name);
 981}
 982
 983static void *ref_list_get_next(const void *a)
 984{
 985        return ((const struct ref *)a)->next;
 986}
 987
 988static void ref_list_set_next(void *a, void *next)
 989{
 990        ((struct ref *)a)->next = next;
 991}
 992
 993void sort_ref_list(struct ref **l, int (*cmp)(const void *, const void *))
 994{
 995        *l = llist_mergesort(*l, ref_list_get_next, ref_list_set_next, cmp);
 996}
 997
 998int count_refspec_match(const char *pattern,
 999                        struct ref *refs,
1000                        struct ref **matched_ref)
1001{
1002        int patlen = strlen(pattern);
1003        struct ref *matched_weak = NULL;
1004        struct ref *matched = NULL;
1005        int weak_match = 0;
1006        int match = 0;
1007
1008        for (weak_match = match = 0; refs; refs = refs->next) {
1009                char *name = refs->name;
1010                int namelen = strlen(name);
1011
1012                if (!refname_match(pattern, name))
1013                        continue;
1014
1015                /* A match is "weak" if it is with refs outside
1016                 * heads or tags, and did not specify the pattern
1017                 * in full (e.g. "refs/remotes/origin/master") or at
1018                 * least from the toplevel (e.g. "remotes/origin/master");
1019                 * otherwise "git push $URL master" would result in
1020                 * ambiguity between remotes/origin/master and heads/master
1021                 * at the remote site.
1022                 */
1023                if (namelen != patlen &&
1024                    patlen != namelen - 5 &&
1025                    !starts_with(name, "refs/heads/") &&
1026                    !starts_with(name, "refs/tags/")) {
1027                        /* We want to catch the case where only weak
1028                         * matches are found and there are multiple
1029                         * matches, and where more than one strong
1030                         * matches are found, as ambiguous.  One
1031                         * strong match with zero or more weak matches
1032                         * are acceptable as a unique match.
1033                         */
1034                        matched_weak = refs;
1035                        weak_match++;
1036                }
1037                else {
1038                        matched = refs;
1039                        match++;
1040                }
1041        }
1042        if (!matched) {
1043                if (matched_ref)
1044                        *matched_ref = matched_weak;
1045                return weak_match;
1046        }
1047        else {
1048                if (matched_ref)
1049                        *matched_ref = matched;
1050                return match;
1051        }
1052}
1053
1054static void tail_link_ref(struct ref *ref, struct ref ***tail)
1055{
1056        **tail = ref;
1057        while (ref->next)
1058                ref = ref->next;
1059        *tail = &ref->next;
1060}
1061
1062static struct ref *alloc_delete_ref(void)
1063{
1064        struct ref *ref = alloc_ref("(delete)");
1065        oidclr(&ref->new_oid);
1066        return ref;
1067}
1068
1069static int try_explicit_object_name(const char *name,
1070                                    struct ref **match)
1071{
1072        struct object_id oid;
1073
1074        if (!*name) {
1075                if (match)
1076                        *match = alloc_delete_ref();
1077                return 0;
1078        }
1079
1080        if (get_sha1(name, oid.hash))
1081                return -1;
1082
1083        if (match) {
1084                *match = alloc_ref(name);
1085                oidcpy(&(*match)->new_oid, &oid);
1086        }
1087        return 0;
1088}
1089
1090static struct ref *make_linked_ref(const char *name, struct ref ***tail)
1091{
1092        struct ref *ret = alloc_ref(name);
1093        tail_link_ref(ret, tail);
1094        return ret;
1095}
1096
1097static char *guess_ref(const char *name, struct ref *peer)
1098{
1099        struct strbuf buf = STRBUF_INIT;
1100        struct object_id oid;
1101
1102        const char *r = resolve_ref_unsafe(peer->name, RESOLVE_REF_READING,
1103                                           oid.hash, NULL);
1104        if (!r)
1105                return NULL;
1106
1107        if (starts_with(r, "refs/heads/"))
1108                strbuf_addstr(&buf, "refs/heads/");
1109        else if (starts_with(r, "refs/tags/"))
1110                strbuf_addstr(&buf, "refs/tags/");
1111        else
1112                return NULL;
1113
1114        strbuf_addstr(&buf, name);
1115        return strbuf_detach(&buf, NULL);
1116}
1117
1118static int match_explicit_lhs(struct ref *src,
1119                              struct refspec *rs,
1120                              struct ref **match,
1121                              int *allocated_match)
1122{
1123        switch (count_refspec_match(rs->src, src, match)) {
1124        case 1:
1125                if (allocated_match)
1126                        *allocated_match = 0;
1127                return 0;
1128        case 0:
1129                /* The source could be in the get_sha1() format
1130                 * not a reference name.  :refs/other is a
1131                 * way to delete 'other' ref at the remote end.
1132                 */
1133                if (try_explicit_object_name(rs->src, match) < 0)
1134                        return error("src refspec %s does not match any.", rs->src);
1135                if (allocated_match)
1136                        *allocated_match = 1;
1137                return 0;
1138        default:
1139                return error("src refspec %s matches more than one.", rs->src);
1140        }
1141}
1142
1143static int match_explicit(struct ref *src, struct ref *dst,
1144                          struct ref ***dst_tail,
1145                          struct refspec *rs)
1146{
1147        struct ref *matched_src, *matched_dst;
1148        int allocated_src;
1149
1150        const char *dst_value = rs->dst;
1151        char *dst_guess;
1152
1153        if (rs->pattern || rs->matching)
1154                return 0;
1155
1156        matched_src = matched_dst = NULL;
1157        if (match_explicit_lhs(src, rs, &matched_src, &allocated_src) < 0)
1158                return -1;
1159
1160        if (!dst_value) {
1161                struct object_id oid;
1162                int flag;
1163
1164                dst_value = resolve_ref_unsafe(matched_src->name,
1165                                               RESOLVE_REF_READING,
1166                                               oid.hash, &flag);
1167                if (!dst_value ||
1168                    ((flag & REF_ISSYMREF) &&
1169                     !starts_with(dst_value, "refs/heads/")))
1170                        die("%s cannot be resolved to branch.",
1171                            matched_src->name);
1172        }
1173
1174        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
1175        case 1:
1176                break;
1177        case 0:
1178                if (starts_with(dst_value, "refs/"))
1179                        matched_dst = make_linked_ref(dst_value, dst_tail);
1180                else if (is_null_oid(&matched_src->new_oid))
1181                        error("unable to delete '%s': remote ref does not exist",
1182                              dst_value);
1183                else if ((dst_guess = guess_ref(dst_value, matched_src))) {
1184                        matched_dst = make_linked_ref(dst_guess, dst_tail);
1185                        free(dst_guess);
1186                } else
1187                        error("unable to push to unqualified destination: %s\n"
1188                              "The destination refspec neither matches an "
1189                              "existing ref on the remote nor\n"
1190                              "begins with refs/, and we are unable to "
1191                              "guess a prefix based on the source ref.",
1192                              dst_value);
1193                break;
1194        default:
1195                matched_dst = NULL;
1196                error("dst refspec %s matches more than one.",
1197                      dst_value);
1198                break;
1199        }
1200        if (!matched_dst)
1201                return -1;
1202        if (matched_dst->peer_ref)
1203                return error("dst ref %s receives from more than one src.",
1204                      matched_dst->name);
1205        else {
1206                matched_dst->peer_ref = allocated_src ?
1207                                        matched_src :
1208                                        copy_ref(matched_src);
1209                matched_dst->force = rs->force;
1210        }
1211        return 0;
1212}
1213
1214static int match_explicit_refs(struct ref *src, struct ref *dst,
1215                               struct ref ***dst_tail, struct refspec *rs,
1216                               int rs_nr)
1217{
1218        int i, errs;
1219        for (i = errs = 0; i < rs_nr; i++)
1220                errs += match_explicit(src, dst, dst_tail, &rs[i]);
1221        return errs;
1222}
1223
1224static char *get_ref_match(const struct refspec *rs, int rs_nr, const struct ref *ref,
1225                int send_mirror, int direction, const struct refspec **ret_pat)
1226{
1227        const struct refspec *pat;
1228        char *name;
1229        int i;
1230        int matching_refs = -1;
1231        for (i = 0; i < rs_nr; i++) {
1232                if (rs[i].matching &&
1233                    (matching_refs == -1 || rs[i].force)) {
1234                        matching_refs = i;
1235                        continue;
1236                }
1237
1238                if (rs[i].pattern) {
1239                        const char *dst_side = rs[i].dst ? rs[i].dst : rs[i].src;
1240                        int match;
1241                        if (direction == FROM_SRC)
1242                                match = match_name_with_pattern(rs[i].src, ref->name, dst_side, &name);
1243                        else
1244                                match = match_name_with_pattern(dst_side, ref->name, rs[i].src, &name);
1245                        if (match) {
1246                                matching_refs = i;
1247                                break;
1248                        }
1249                }
1250        }
1251        if (matching_refs == -1)
1252                return NULL;
1253
1254        pat = rs + matching_refs;
1255        if (pat->matching) {
1256                /*
1257                 * "matching refs"; traditionally we pushed everything
1258                 * including refs outside refs/heads/ hierarchy, but
1259                 * that does not make much sense these days.
1260                 */
1261                if (!send_mirror && !starts_with(ref->name, "refs/heads/"))
1262                        return NULL;
1263                name = xstrdup(ref->name);
1264        }
1265        if (ret_pat)
1266                *ret_pat = pat;
1267        return name;
1268}
1269
1270static struct ref **tail_ref(struct ref **head)
1271{
1272        struct ref **tail = head;
1273        while (*tail)
1274                tail = &((*tail)->next);
1275        return tail;
1276}
1277
1278struct tips {
1279        struct commit **tip;
1280        int nr, alloc;
1281};
1282
1283static void add_to_tips(struct tips *tips, const struct object_id *oid)
1284{
1285        struct commit *commit;
1286
1287        if (is_null_oid(oid))
1288                return;
1289        commit = lookup_commit_reference_gently(oid->hash, 1);
1290        if (!commit || (commit->object.flags & TMP_MARK))
1291                return;
1292        commit->object.flags |= TMP_MARK;
1293        ALLOC_GROW(tips->tip, tips->nr + 1, tips->alloc);
1294        tips->tip[tips->nr++] = commit;
1295}
1296
1297static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***dst_tail)
1298{
1299        struct string_list dst_tag = STRING_LIST_INIT_NODUP;
1300        struct string_list src_tag = STRING_LIST_INIT_NODUP;
1301        struct string_list_item *item;
1302        struct ref *ref;
1303        struct tips sent_tips;
1304
1305        /*
1306         * Collect everything we know they would have at the end of
1307         * this push, and collect all tags they have.
1308         */
1309        memset(&sent_tips, 0, sizeof(sent_tips));
1310        for (ref = *dst; ref; ref = ref->next) {
1311                if (ref->peer_ref &&
1312                    !is_null_oid(&ref->peer_ref->new_oid))
1313                        add_to_tips(&sent_tips, &ref->peer_ref->new_oid);
1314                else
1315                        add_to_tips(&sent_tips, &ref->old_oid);
1316                if (starts_with(ref->name, "refs/tags/"))
1317                        string_list_append(&dst_tag, ref->name);
1318        }
1319        clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
1320
1321        string_list_sort(&dst_tag);
1322
1323        /* Collect tags they do not have. */
1324        for (ref = src; ref; ref = ref->next) {
1325                if (!starts_with(ref->name, "refs/tags/"))
1326                        continue; /* not a tag */
1327                if (string_list_has_string(&dst_tag, ref->name))
1328                        continue; /* they already have it */
1329                if (sha1_object_info(ref->new_oid.hash, NULL) != OBJ_TAG)
1330                        continue; /* be conservative */
1331                item = string_list_append(&src_tag, ref->name);
1332                item->util = ref;
1333        }
1334        string_list_clear(&dst_tag, 0);
1335
1336        /*
1337         * At this point, src_tag lists tags that are missing from
1338         * dst, and sent_tips lists the tips we are pushing or those
1339         * that we know they already have. An element in the src_tag
1340         * that is an ancestor of any of the sent_tips needs to be
1341         * sent to the other side.
1342         */
1343        if (sent_tips.nr) {
1344                for_each_string_list_item(item, &src_tag) {
1345                        struct ref *ref = item->util;
1346                        struct ref *dst_ref;
1347                        struct commit *commit;
1348
1349                        if (is_null_oid(&ref->new_oid))
1350                                continue;
1351                        commit = lookup_commit_reference_gently(ref->new_oid.hash, 1);
1352                        if (!commit)
1353                                /* not pushing a commit, which is not an error */
1354                                continue;
1355
1356                        /*
1357                         * Is this tag, which they do not have, reachable from
1358                         * any of the commits we are sending?
1359                         */
1360                        if (!in_merge_bases_many(commit, sent_tips.nr, sent_tips.tip))
1361                                continue;
1362
1363                        /* Add it in */
1364                        dst_ref = make_linked_ref(ref->name, dst_tail);
1365                        oidcpy(&dst_ref->new_oid, &ref->new_oid);
1366                        dst_ref->peer_ref = copy_ref(ref);
1367                }
1368        }
1369        string_list_clear(&src_tag, 0);
1370        free(sent_tips.tip);
1371}
1372
1373struct ref *find_ref_by_name(const struct ref *list, const char *name)
1374{
1375        for ( ; list; list = list->next)
1376                if (!strcmp(list->name, name))
1377                        return (struct ref *)list;
1378        return NULL;
1379}
1380
1381static void prepare_ref_index(struct string_list *ref_index, struct ref *ref)
1382{
1383        for ( ; ref; ref = ref->next)
1384                string_list_append_nodup(ref_index, ref->name)->util = ref;
1385
1386        string_list_sort(ref_index);
1387}
1388
1389/*
1390 * Given only the set of local refs, sanity-check the set of push
1391 * refspecs. We can't catch all errors that match_push_refs would,
1392 * but we can catch some errors early before even talking to the
1393 * remote side.
1394 */
1395int check_push_refs(struct ref *src, int nr_refspec, const char **refspec_names)
1396{
1397        struct refspec *refspec = parse_push_refspec(nr_refspec, refspec_names);
1398        int ret = 0;
1399        int i;
1400
1401        for (i = 0; i < nr_refspec; i++) {
1402                struct refspec *rs = refspec + i;
1403
1404                if (rs->pattern || rs->matching)
1405                        continue;
1406
1407                ret |= match_explicit_lhs(src, rs, NULL, NULL);
1408        }
1409
1410        free_refspec(nr_refspec, refspec);
1411        return ret;
1412}
1413
1414/*
1415 * Given the set of refs the local repository has, the set of refs the
1416 * remote repository has, and the refspec used for push, determine
1417 * what remote refs we will update and with what value by setting
1418 * peer_ref (which object is being pushed) and force (if the push is
1419 * forced) in elements of "dst". The function may add new elements to
1420 * dst (e.g. pushing to a new branch, done in match_explicit_refs).
1421 */
1422int match_push_refs(struct ref *src, struct ref **dst,
1423                    int nr_refspec, const char **refspec, int flags)
1424{
1425        struct refspec *rs;
1426        int send_all = flags & MATCH_REFS_ALL;
1427        int send_mirror = flags & MATCH_REFS_MIRROR;
1428        int send_prune = flags & MATCH_REFS_PRUNE;
1429        int errs;
1430        static const char *default_refspec[] = { ":", NULL };
1431        struct ref *ref, **dst_tail = tail_ref(dst);
1432        struct string_list dst_ref_index = STRING_LIST_INIT_NODUP;
1433
1434        if (!nr_refspec) {
1435                nr_refspec = 1;
1436                refspec = default_refspec;
1437        }
1438        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1439        errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
1440
1441        /* pick the remainder */
1442        for (ref = src; ref; ref = ref->next) {
1443                struct string_list_item *dst_item;
1444                struct ref *dst_peer;
1445                const struct refspec *pat = NULL;
1446                char *dst_name;
1447
1448                dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
1449                if (!dst_name)
1450                        continue;
1451
1452                if (!dst_ref_index.nr)
1453                        prepare_ref_index(&dst_ref_index, *dst);
1454
1455                dst_item = string_list_lookup(&dst_ref_index, dst_name);
1456                dst_peer = dst_item ? dst_item->util : NULL;
1457                if (dst_peer) {
1458                        if (dst_peer->peer_ref)
1459                                /* We're already sending something to this ref. */
1460                                goto free_name;
1461                } else {
1462                        if (pat->matching && !(send_all || send_mirror))
1463                                /*
1464                                 * Remote doesn't have it, and we have no
1465                                 * explicit pattern, and we don't have
1466                                 * --all or --mirror.
1467                                 */
1468                                goto free_name;
1469
1470                        /* Create a new one and link it */
1471                        dst_peer = make_linked_ref(dst_name, &dst_tail);
1472                        oidcpy(&dst_peer->new_oid, &ref->new_oid);
1473                        string_list_insert(&dst_ref_index,
1474                                dst_peer->name)->util = dst_peer;
1475                }
1476                dst_peer->peer_ref = copy_ref(ref);
1477                dst_peer->force = pat->force;
1478        free_name:
1479                free(dst_name);
1480        }
1481
1482        string_list_clear(&dst_ref_index, 0);
1483
1484        if (flags & MATCH_REFS_FOLLOW_TAGS)
1485                add_missing_tags(src, dst, &dst_tail);
1486
1487        if (send_prune) {
1488                struct string_list src_ref_index = STRING_LIST_INIT_NODUP;
1489                /* check for missing refs on the remote */
1490                for (ref = *dst; ref; ref = ref->next) {
1491                        char *src_name;
1492
1493                        if (ref->peer_ref)
1494                                /* We're already sending something to this ref. */
1495                                continue;
1496
1497                        src_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_DST, NULL);
1498                        if (src_name) {
1499                                if (!src_ref_index.nr)
1500                                        prepare_ref_index(&src_ref_index, src);
1501                                if (!string_list_has_string(&src_ref_index,
1502                                            src_name))
1503                                        ref->peer_ref = alloc_delete_ref();
1504                                free(src_name);
1505                        }
1506                }
1507                string_list_clear(&src_ref_index, 0);
1508        }
1509        if (errs)
1510                return -1;
1511        return 0;
1512}
1513
1514void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
1515                             int force_update)
1516{
1517        struct ref *ref;
1518
1519        for (ref = remote_refs; ref; ref = ref->next) {
1520                int force_ref_update = ref->force || force_update;
1521                int reject_reason = 0;
1522
1523                if (ref->peer_ref)
1524                        oidcpy(&ref->new_oid, &ref->peer_ref->new_oid);
1525                else if (!send_mirror)
1526                        continue;
1527
1528                ref->deletion = is_null_oid(&ref->new_oid);
1529                if (!ref->deletion &&
1530                        !oidcmp(&ref->old_oid, &ref->new_oid)) {
1531                        ref->status = REF_STATUS_UPTODATE;
1532                        continue;
1533                }
1534
1535                /*
1536                 * If the remote ref has moved and is now different
1537                 * from what we expect, reject any push.
1538                 *
1539                 * It also is an error if the user told us to check
1540                 * with the remote-tracking branch to find the value
1541                 * to expect, but we did not have such a tracking
1542                 * branch.
1543                 */
1544                if (ref->expect_old_sha1) {
1545                        if (oidcmp(&ref->old_oid, &ref->old_oid_expect))
1546                                reject_reason = REF_STATUS_REJECT_STALE;
1547                        else
1548                                /* If the ref isn't stale then force the update. */
1549                                force_ref_update = 1;
1550                }
1551
1552                /*
1553                 * If the update isn't already rejected then check
1554                 * the usual "must fast-forward" rules.
1555                 *
1556                 * Decide whether an individual refspec A:B can be
1557                 * pushed.  The push will succeed if any of the
1558                 * following are true:
1559                 *
1560                 * (1) the remote reference B does not exist
1561                 *
1562                 * (2) the remote reference B is being removed (i.e.,
1563                 *     pushing :B where no source is specified)
1564                 *
1565                 * (3) the destination is not under refs/tags/, and
1566                 *     if the old and new value is a commit, the new
1567                 *     is a descendant of the old.
1568                 *
1569                 * (4) it is forced using the +A:B notation, or by
1570                 *     passing the --force argument
1571                 */
1572
1573                if (!reject_reason && !ref->deletion && !is_null_oid(&ref->old_oid)) {
1574                        if (starts_with(ref->name, "refs/tags/"))
1575                                reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
1576                        else if (!has_object_file(&ref->old_oid))
1577                                reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
1578                        else if (!lookup_commit_reference_gently(ref->old_oid.hash, 1) ||
1579                                 !lookup_commit_reference_gently(ref->new_oid.hash, 1))
1580                                reject_reason = REF_STATUS_REJECT_NEEDS_FORCE;
1581                        else if (!ref_newer(&ref->new_oid, &ref->old_oid))
1582                                reject_reason = REF_STATUS_REJECT_NONFASTFORWARD;
1583                }
1584
1585                /*
1586                 * "--force" will defeat any rejection implemented
1587                 * by the rules above.
1588                 */
1589                if (!force_ref_update)
1590                        ref->status = reject_reason;
1591                else if (reject_reason)
1592                        ref->forced_update = 1;
1593        }
1594}
1595
1596static void set_merge(struct branch *ret)
1597{
1598        struct remote *remote;
1599        char *ref;
1600        struct object_id oid;
1601        int i;
1602
1603        if (!ret)
1604                return; /* no branch */
1605        if (ret->merge)
1606                return; /* already run */
1607        if (!ret->remote_name || !ret->merge_nr) {
1608                /*
1609                 * no merge config; let's make sure we don't confuse callers
1610                 * with a non-zero merge_nr but a NULL merge
1611                 */
1612                ret->merge_nr = 0;
1613                return;
1614        }
1615
1616        remote = remote_get(ret->remote_name);
1617
1618        ret->merge = xcalloc(ret->merge_nr, sizeof(*ret->merge));
1619        for (i = 0; i < ret->merge_nr; i++) {
1620                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1621                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1622                if (!remote_find_tracking(remote, ret->merge[i]) ||
1623                    strcmp(ret->remote_name, "."))
1624                        continue;
1625                if (dwim_ref(ret->merge_name[i], strlen(ret->merge_name[i]),
1626                             oid.hash, &ref) == 1)
1627                        ret->merge[i]->dst = ref;
1628                else
1629                        ret->merge[i]->dst = xstrdup(ret->merge_name[i]);
1630        }
1631}
1632
1633struct branch *branch_get(const char *name)
1634{
1635        struct branch *ret;
1636
1637        read_config();
1638        if (!name || !*name || !strcmp(name, "HEAD"))
1639                ret = current_branch;
1640        else
1641                ret = make_branch(name, 0);
1642        set_merge(ret);
1643        return ret;
1644}
1645
1646int branch_has_merge_config(struct branch *branch)
1647{
1648        return branch && !!branch->merge;
1649}
1650
1651int branch_merge_matches(struct branch *branch,
1652                                 int i,
1653                                 const char *refname)
1654{
1655        if (!branch || i < 0 || i >= branch->merge_nr)
1656                return 0;
1657        return refname_match(branch->merge[i]->src, refname);
1658}
1659
1660__attribute__((format (printf,2,3)))
1661static const char *error_buf(struct strbuf *err, const char *fmt, ...)
1662{
1663        if (err) {
1664                va_list ap;
1665                va_start(ap, fmt);
1666                strbuf_vaddf(err, fmt, ap);
1667                va_end(ap);
1668        }
1669        return NULL;
1670}
1671
1672const char *branch_get_upstream(struct branch *branch, struct strbuf *err)
1673{
1674        if (!branch)
1675                return error_buf(err, _("HEAD does not point to a branch"));
1676
1677        if (!branch->merge || !branch->merge[0]) {
1678                /*
1679                 * no merge config; is it because the user didn't define any,
1680                 * or because it is not a real branch, and get_branch
1681                 * auto-vivified it?
1682                 */
1683                if (!ref_exists(branch->refname))
1684                        return error_buf(err, _("no such branch: '%s'"),
1685                                         branch->name);
1686                return error_buf(err,
1687                                 _("no upstream configured for branch '%s'"),
1688                                 branch->name);
1689        }
1690
1691        if (!branch->merge[0]->dst)
1692                return error_buf(err,
1693                                 _("upstream branch '%s' not stored as a remote-tracking branch"),
1694                                 branch->merge[0]->src);
1695
1696        return branch->merge[0]->dst;
1697}
1698
1699static const char *tracking_for_push_dest(struct remote *remote,
1700                                          const char *refname,
1701                                          struct strbuf *err)
1702{
1703        char *ret;
1704
1705        ret = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
1706        if (!ret)
1707                return error_buf(err,
1708                                 _("push destination '%s' on remote '%s' has no local tracking branch"),
1709                                 refname, remote->name);
1710        return ret;
1711}
1712
1713static const char *branch_get_push_1(struct branch *branch, struct strbuf *err)
1714{
1715        struct remote *remote;
1716
1717        remote = remote_get(pushremote_for_branch(branch, NULL));
1718        if (!remote)
1719                return error_buf(err,
1720                                 _("branch '%s' has no remote for pushing"),
1721                                 branch->name);
1722
1723        if (remote->push_refspec_nr) {
1724                char *dst;
1725                const char *ret;
1726
1727                dst = apply_refspecs(remote->push, remote->push_refspec_nr,
1728                                     branch->refname);
1729                if (!dst)
1730                        return error_buf(err,
1731                                         _("push refspecs for '%s' do not include '%s'"),
1732                                         remote->name, branch->name);
1733
1734                ret = tracking_for_push_dest(remote, dst, err);
1735                free(dst);
1736                return ret;
1737        }
1738
1739        if (remote->mirror)
1740                return tracking_for_push_dest(remote, branch->refname, err);
1741
1742        switch (push_default) {
1743        case PUSH_DEFAULT_NOTHING:
1744                return error_buf(err, _("push has no destination (push.default is 'nothing')"));
1745
1746        case PUSH_DEFAULT_MATCHING:
1747        case PUSH_DEFAULT_CURRENT:
1748                return tracking_for_push_dest(remote, branch->refname, err);
1749
1750        case PUSH_DEFAULT_UPSTREAM:
1751                return branch_get_upstream(branch, err);
1752
1753        case PUSH_DEFAULT_UNSPECIFIED:
1754        case PUSH_DEFAULT_SIMPLE:
1755                {
1756                        const char *up, *cur;
1757
1758                        up = branch_get_upstream(branch, err);
1759                        if (!up)
1760                                return NULL;
1761                        cur = tracking_for_push_dest(remote, branch->refname, err);
1762                        if (!cur)
1763                                return NULL;
1764                        if (strcmp(cur, up))
1765                                return error_buf(err,
1766                                                 _("cannot resolve 'simple' push to a single destination"));
1767                        return cur;
1768                }
1769        }
1770
1771        die("BUG: unhandled push situation");
1772}
1773
1774const char *branch_get_push(struct branch *branch, struct strbuf *err)
1775{
1776        if (!branch)
1777                return error_buf(err, _("HEAD does not point to a branch"));
1778
1779        if (!branch->push_tracking_ref)
1780                branch->push_tracking_ref = branch_get_push_1(branch, err);
1781        return branch->push_tracking_ref;
1782}
1783
1784static int ignore_symref_update(const char *refname)
1785{
1786        struct object_id oid;
1787        int flag;
1788
1789        if (!resolve_ref_unsafe(refname, 0, oid.hash, &flag))
1790                return 0; /* non-existing refs are OK */
1791        return (flag & REF_ISSYMREF);
1792}
1793
1794/*
1795 * Create and return a list of (struct ref) consisting of copies of
1796 * each remote_ref that matches refspec.  refspec must be a pattern.
1797 * Fill in the copies' peer_ref to describe the local tracking refs to
1798 * which they map.  Omit any references that would map to an existing
1799 * local symbolic ref.
1800 */
1801static struct ref *get_expanded_map(const struct ref *remote_refs,
1802                                    const struct refspec *refspec)
1803{
1804        const struct ref *ref;
1805        struct ref *ret = NULL;
1806        struct ref **tail = &ret;
1807
1808        for (ref = remote_refs; ref; ref = ref->next) {
1809                char *expn_name = NULL;
1810
1811                if (strchr(ref->name, '^'))
1812                        continue; /* a dereference item */
1813                if (match_name_with_pattern(refspec->src, ref->name,
1814                                            refspec->dst, &expn_name) &&
1815                    !ignore_symref_update(expn_name)) {
1816                        struct ref *cpy = copy_ref(ref);
1817
1818                        cpy->peer_ref = alloc_ref(expn_name);
1819                        if (refspec->force)
1820                                cpy->peer_ref->force = 1;
1821                        *tail = cpy;
1822                        tail = &cpy->next;
1823                }
1824                free(expn_name);
1825        }
1826
1827        return ret;
1828}
1829
1830static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1831{
1832        const struct ref *ref;
1833        for (ref = refs; ref; ref = ref->next) {
1834                if (refname_match(name, ref->name))
1835                        return ref;
1836        }
1837        return NULL;
1838}
1839
1840struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1841{
1842        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1843
1844        if (!ref)
1845                return NULL;
1846
1847        return copy_ref(ref);
1848}
1849
1850static struct ref *get_local_ref(const char *name)
1851{
1852        if (!name || name[0] == '\0')
1853                return NULL;
1854
1855        if (starts_with(name, "refs/"))
1856                return alloc_ref(name);
1857
1858        if (starts_with(name, "heads/") ||
1859            starts_with(name, "tags/") ||
1860            starts_with(name, "remotes/"))
1861                return alloc_ref_with_prefix("refs/", 5, name);
1862
1863        return alloc_ref_with_prefix("refs/heads/", 11, name);
1864}
1865
1866int get_fetch_map(const struct ref *remote_refs,
1867                  const struct refspec *refspec,
1868                  struct ref ***tail,
1869                  int missing_ok)
1870{
1871        struct ref *ref_map, **rmp;
1872
1873        if (refspec->pattern) {
1874                ref_map = get_expanded_map(remote_refs, refspec);
1875        } else {
1876                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1877
1878                if (refspec->exact_sha1) {
1879                        ref_map = alloc_ref(name);
1880                        get_oid_hex(name, &ref_map->old_oid);
1881                } else {
1882                        ref_map = get_remote_ref(remote_refs, name);
1883                }
1884                if (!missing_ok && !ref_map)
1885                        die("Couldn't find remote ref %s", name);
1886                if (ref_map) {
1887                        ref_map->peer_ref = get_local_ref(refspec->dst);
1888                        if (ref_map->peer_ref && refspec->force)
1889                                ref_map->peer_ref->force = 1;
1890                }
1891        }
1892
1893        for (rmp = &ref_map; *rmp; ) {
1894                if ((*rmp)->peer_ref) {
1895                        if (!starts_with((*rmp)->peer_ref->name, "refs/") ||
1896                            check_refname_format((*rmp)->peer_ref->name, 0)) {
1897                                struct ref *ignore = *rmp;
1898                                error("* Ignoring funny ref '%s' locally",
1899                                      (*rmp)->peer_ref->name);
1900                                *rmp = (*rmp)->next;
1901                                free(ignore->peer_ref);
1902                                free(ignore);
1903                                continue;
1904                        }
1905                }
1906                rmp = &((*rmp)->next);
1907        }
1908
1909        if (ref_map)
1910                tail_link_ref(ref_map, tail);
1911
1912        return 0;
1913}
1914
1915int resolve_remote_symref(struct ref *ref, struct ref *list)
1916{
1917        if (!ref->symref)
1918                return 0;
1919        for (; list; list = list->next)
1920                if (!strcmp(ref->symref, list->name)) {
1921                        oidcpy(&ref->old_oid, &list->old_oid);
1922                        return 0;
1923                }
1924        return 1;
1925}
1926
1927static void unmark_and_free(struct commit_list *list, unsigned int mark)
1928{
1929        while (list) {
1930                struct commit *commit = pop_commit(&list);
1931                commit->object.flags &= ~mark;
1932        }
1933}
1934
1935int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid)
1936{
1937        struct object *o;
1938        struct commit *old, *new;
1939        struct commit_list *list, *used;
1940        int found = 0;
1941
1942        /*
1943         * Both new and old must be commit-ish and new is descendant of
1944         * old.  Otherwise we require --force.
1945         */
1946        o = deref_tag(parse_object(old_oid->hash), NULL, 0);
1947        if (!o || o->type != OBJ_COMMIT)
1948                return 0;
1949        old = (struct commit *) o;
1950
1951        o = deref_tag(parse_object(new_oid->hash), NULL, 0);
1952        if (!o || o->type != OBJ_COMMIT)
1953                return 0;
1954        new = (struct commit *) o;
1955
1956        if (parse_commit(new) < 0)
1957                return 0;
1958
1959        used = list = NULL;
1960        commit_list_insert(new, &list);
1961        while (list) {
1962                new = pop_most_recent_commit(&list, TMP_MARK);
1963                commit_list_insert(new, &used);
1964                if (new == old) {
1965                        found = 1;
1966                        break;
1967                }
1968        }
1969        unmark_and_free(list, TMP_MARK);
1970        unmark_and_free(used, TMP_MARK);
1971        return found;
1972}
1973
1974/*
1975 * Compare a branch with its upstream, and save their differences (number
1976 * of commits) in *num_ours and *num_theirs. The name of the upstream branch
1977 * (or NULL if no upstream is defined) is returned via *upstream_name, if it
1978 * is not itself NULL.
1979 *
1980 * Returns -1 if num_ours and num_theirs could not be filled in (e.g., no
1981 * upstream defined, or ref does not exist), 0 otherwise.
1982 */
1983int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs,
1984                       const char **upstream_name)
1985{
1986        struct object_id oid;
1987        struct commit *ours, *theirs;
1988        struct rev_info revs;
1989        const char *base;
1990        struct argv_array argv = ARGV_ARRAY_INIT;
1991
1992        /* Cannot stat unless we are marked to build on top of somebody else. */
1993        base = branch_get_upstream(branch, NULL);
1994        if (upstream_name)
1995                *upstream_name = base;
1996        if (!base)
1997                return -1;
1998
1999        /* Cannot stat if what we used to build on no longer exists */
2000        if (read_ref(base, oid.hash))
2001                return -1;
2002        theirs = lookup_commit_reference(oid.hash);
2003        if (!theirs)
2004                return -1;
2005
2006        if (read_ref(branch->refname, oid.hash))
2007                return -1;
2008        ours = lookup_commit_reference(oid.hash);
2009        if (!ours)
2010                return -1;
2011
2012        /* are we the same? */
2013        if (theirs == ours) {
2014                *num_theirs = *num_ours = 0;
2015                return 0;
2016        }
2017
2018        /* Run "rev-list --left-right ours...theirs" internally... */
2019        argv_array_push(&argv, ""); /* ignored */
2020        argv_array_push(&argv, "--left-right");
2021        argv_array_pushf(&argv, "%s...%s",
2022                         oid_to_hex(&ours->object.oid),
2023                         oid_to_hex(&theirs->object.oid));
2024        argv_array_push(&argv, "--");
2025
2026        init_revisions(&revs, NULL);
2027        setup_revisions(argv.argc, argv.argv, &revs, NULL);
2028        if (prepare_revision_walk(&revs))
2029                die("revision walk setup failed");
2030
2031        /* ... and count the commits on each side. */
2032        *num_ours = 0;
2033        *num_theirs = 0;
2034        while (1) {
2035                struct commit *c = get_revision(&revs);
2036                if (!c)
2037                        break;
2038                if (c->object.flags & SYMMETRIC_LEFT)
2039                        (*num_ours)++;
2040                else
2041                        (*num_theirs)++;
2042        }
2043
2044        /* clear object flags smudged by the above traversal */
2045        clear_commit_marks(ours, ALL_REV_FLAGS);
2046        clear_commit_marks(theirs, ALL_REV_FLAGS);
2047
2048        argv_array_clear(&argv);
2049        return 0;
2050}
2051
2052/*
2053 * Return true when there is anything to report, otherwise false.
2054 */
2055int format_tracking_info(struct branch *branch, struct strbuf *sb)
2056{
2057        int ours, theirs;
2058        const char *full_base;
2059        char *base;
2060        int upstream_is_gone = 0;
2061
2062        if (stat_tracking_info(branch, &ours, &theirs, &full_base) < 0) {
2063                if (!full_base)
2064                        return 0;
2065                upstream_is_gone = 1;
2066        }
2067
2068        base = shorten_unambiguous_ref(full_base, 0);
2069        if (upstream_is_gone) {
2070                strbuf_addf(sb,
2071                        _("Your branch is based on '%s', but the upstream is gone.\n"),
2072                        base);
2073                if (advice_status_hints)
2074                        strbuf_addstr(sb,
2075                                _("  (use \"git branch --unset-upstream\" to fixup)\n"));
2076        } else if (!ours && !theirs) {
2077                strbuf_addf(sb,
2078                        _("Your branch is up-to-date with '%s'.\n"),
2079                        base);
2080        } else if (!theirs) {
2081                strbuf_addf(sb,
2082                        Q_("Your branch is ahead of '%s' by %d commit.\n",
2083                           "Your branch is ahead of '%s' by %d commits.\n",
2084                           ours),
2085                        base, ours);
2086                if (advice_status_hints)
2087                        strbuf_addstr(sb,
2088                                _("  (use \"git push\" to publish your local commits)\n"));
2089        } else if (!ours) {
2090                strbuf_addf(sb,
2091                        Q_("Your branch is behind '%s' by %d commit, "
2092                               "and can be fast-forwarded.\n",
2093                           "Your branch is behind '%s' by %d commits, "
2094                               "and can be fast-forwarded.\n",
2095                           theirs),
2096                        base, theirs);
2097                if (advice_status_hints)
2098                        strbuf_addstr(sb,
2099                                _("  (use \"git pull\" to update your local branch)\n"));
2100        } else {
2101                strbuf_addf(sb,
2102                        Q_("Your branch and '%s' have diverged,\n"
2103                               "and have %d and %d different commit each, "
2104                               "respectively.\n",
2105                           "Your branch and '%s' have diverged,\n"
2106                               "and have %d and %d different commits each, "
2107                               "respectively.\n",
2108                           ours + theirs),
2109                        base, ours, theirs);
2110                if (advice_status_hints)
2111                        strbuf_addstr(sb,
2112                                _("  (use \"git pull\" to merge the remote branch into yours)\n"));
2113        }
2114        free(base);
2115        return 1;
2116}
2117
2118static int one_local_ref(const char *refname, const struct object_id *oid,
2119                         int flag, void *cb_data)
2120{
2121        struct ref ***local_tail = cb_data;
2122        struct ref *ref;
2123
2124        /* we already know it starts with refs/ to get here */
2125        if (check_refname_format(refname + 5, 0))
2126                return 0;
2127
2128        ref = alloc_ref(refname);
2129        oidcpy(&ref->new_oid, oid);
2130        **local_tail = ref;
2131        *local_tail = &ref->next;
2132        return 0;
2133}
2134
2135struct ref *get_local_heads(void)
2136{
2137        struct ref *local_refs = NULL, **local_tail = &local_refs;
2138
2139        for_each_ref(one_local_ref, &local_tail);
2140        return local_refs;
2141}
2142
2143struct ref *guess_remote_head(const struct ref *head,
2144                              const struct ref *refs,
2145                              int all)
2146{
2147        const struct ref *r;
2148        struct ref *list = NULL;
2149        struct ref **tail = &list;
2150
2151        if (!head)
2152                return NULL;
2153
2154        /*
2155         * Some transports support directly peeking at
2156         * where HEAD points; if that is the case, then
2157         * we don't have to guess.
2158         */
2159        if (head->symref)
2160                return copy_ref(find_ref_by_name(refs, head->symref));
2161
2162        /* If refs/heads/master could be right, it is. */
2163        if (!all) {
2164                r = find_ref_by_name(refs, "refs/heads/master");
2165                if (r && !oidcmp(&r->old_oid, &head->old_oid))
2166                        return copy_ref(r);
2167        }
2168
2169        /* Look for another ref that points there */
2170        for (r = refs; r; r = r->next) {
2171                if (r != head &&
2172                    starts_with(r->name, "refs/heads/") &&
2173                    !oidcmp(&r->old_oid, &head->old_oid)) {
2174                        *tail = copy_ref(r);
2175                        tail = &((*tail)->next);
2176                        if (!all)
2177                                break;
2178                }
2179        }
2180
2181        return list;
2182}
2183
2184struct stale_heads_info {
2185        struct string_list *ref_names;
2186        struct ref **stale_refs_tail;
2187        struct refspec *refs;
2188        int ref_count;
2189};
2190
2191static int get_stale_heads_cb(const char *refname, const struct object_id *oid,
2192                              int flags, void *cb_data)
2193{
2194        struct stale_heads_info *info = cb_data;
2195        struct string_list matches = STRING_LIST_INIT_DUP;
2196        struct refspec query;
2197        int i, stale = 1;
2198        memset(&query, 0, sizeof(struct refspec));
2199        query.dst = (char *)refname;
2200
2201        query_refspecs_multiple(info->refs, info->ref_count, &query, &matches);
2202        if (matches.nr == 0)
2203                goto clean_exit; /* No matches */
2204
2205        /*
2206         * If we did find a suitable refspec and it's not a symref and
2207         * it's not in the list of refs that currently exist in that
2208         * remote, we consider it to be stale. In order to deal with
2209         * overlapping refspecs, we need to go over all of the
2210         * matching refs.
2211         */
2212        if (flags & REF_ISSYMREF)
2213                goto clean_exit;
2214
2215        for (i = 0; stale && i < matches.nr; i++)
2216                if (string_list_has_string(info->ref_names, matches.items[i].string))
2217                        stale = 0;
2218
2219        if (stale) {
2220                struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
2221                oidcpy(&ref->new_oid, oid);
2222        }
2223
2224clean_exit:
2225        string_list_clear(&matches, 0);
2226        return 0;
2227}
2228
2229struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fetch_map)
2230{
2231        struct ref *ref, *stale_refs = NULL;
2232        struct string_list ref_names = STRING_LIST_INIT_NODUP;
2233        struct stale_heads_info info;
2234
2235        info.ref_names = &ref_names;
2236        info.stale_refs_tail = &stale_refs;
2237        info.refs = refs;
2238        info.ref_count = ref_count;
2239        for (ref = fetch_map; ref; ref = ref->next)
2240                string_list_append(&ref_names, ref->name);
2241        string_list_sort(&ref_names);
2242        for_each_ref(get_stale_heads_cb, &info);
2243        string_list_clear(&ref_names, 0);
2244        return stale_refs;
2245}
2246
2247/*
2248 * Compare-and-swap
2249 */
2250static void clear_cas_option(struct push_cas_option *cas)
2251{
2252        int i;
2253
2254        for (i = 0; i < cas->nr; i++)
2255                free(cas->entry[i].refname);
2256        free(cas->entry);
2257        memset(cas, 0, sizeof(*cas));
2258}
2259
2260static struct push_cas *add_cas_entry(struct push_cas_option *cas,
2261                                      const char *refname,
2262                                      size_t refnamelen)
2263{
2264        struct push_cas *entry;
2265        ALLOC_GROW(cas->entry, cas->nr + 1, cas->alloc);
2266        entry = &cas->entry[cas->nr++];
2267        memset(entry, 0, sizeof(*entry));
2268        entry->refname = xmemdupz(refname, refnamelen);
2269        return entry;
2270}
2271
2272static int parse_push_cas_option(struct push_cas_option *cas, const char *arg, int unset)
2273{
2274        const char *colon;
2275        struct push_cas *entry;
2276
2277        if (unset) {
2278                /* "--no-<option>" */
2279                clear_cas_option(cas);
2280                return 0;
2281        }
2282
2283        if (!arg) {
2284                /* just "--<option>" */
2285                cas->use_tracking_for_rest = 1;
2286                return 0;
2287        }
2288
2289        /* "--<option>=refname" or "--<option>=refname:value" */
2290        colon = strchrnul(arg, ':');
2291        entry = add_cas_entry(cas, arg, colon - arg);
2292        if (!*colon)
2293                entry->use_tracking = 1;
2294        else if (!colon[1])
2295                hashclr(entry->expect);
2296        else if (get_sha1(colon + 1, entry->expect))
2297                return error("cannot parse expected object name '%s'", colon + 1);
2298        return 0;
2299}
2300
2301int parseopt_push_cas_option(const struct option *opt, const char *arg, int unset)
2302{
2303        return parse_push_cas_option(opt->value, arg, unset);
2304}
2305
2306int is_empty_cas(const struct push_cas_option *cas)
2307{
2308        return !cas->use_tracking_for_rest && !cas->nr;
2309}
2310
2311/*
2312 * Look at remote.fetch refspec and see if we have a remote
2313 * tracking branch for the refname there.  Fill its current
2314 * value in sha1[].
2315 * If we cannot do so, return negative to signal an error.
2316 */
2317static int remote_tracking(struct remote *remote, const char *refname,
2318                           struct object_id *oid)
2319{
2320        char *dst;
2321
2322        dst = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
2323        if (!dst)
2324                return -1; /* no tracking ref for refname at remote */
2325        if (read_ref(dst, oid->hash))
2326                return -1; /* we know what the tracking ref is but we cannot read it */
2327        return 0;
2328}
2329
2330static void apply_cas(struct push_cas_option *cas,
2331                      struct remote *remote,
2332                      struct ref *ref)
2333{
2334        int i;
2335
2336        /* Find an explicit --<option>=<name>[:<value>] entry */
2337        for (i = 0; i < cas->nr; i++) {
2338                struct push_cas *entry = &cas->entry[i];
2339                if (!refname_match(entry->refname, ref->name))
2340                        continue;
2341                ref->expect_old_sha1 = 1;
2342                if (!entry->use_tracking)
2343                        hashcpy(ref->old_oid_expect.hash, cas->entry[i].expect);
2344                else if (remote_tracking(remote, ref->name, &ref->old_oid_expect))
2345                        oidclr(&ref->old_oid_expect);
2346                return;
2347        }
2348
2349        /* Are we using "--<option>" to cover all? */
2350        if (!cas->use_tracking_for_rest)
2351                return;
2352
2353        ref->expect_old_sha1 = 1;
2354        if (remote_tracking(remote, ref->name, &ref->old_oid_expect))
2355                oidclr(&ref->old_oid_expect);
2356}
2357
2358void apply_push_cas(struct push_cas_option *cas,
2359                    struct remote *remote,
2360                    struct ref *remote_refs)
2361{
2362        struct ref *ref;
2363        for (ref = remote_refs; ref; ref = ref->next)
2364                apply_cas(cas, remote, ref);
2365}