remote.con commit git-p4: add trap to kill p4d on test exit (dfe90e8)
   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->origin = REMOTE_REMOTES;
 259        while (strbuf_getline(&buf, f, '\n') != EOF) {
 260                const char *v;
 261
 262                strbuf_rtrim(&buf);
 263
 264                if (skip_prefix(buf.buf, "URL:", &v))
 265                        add_url_alias(remote, xstrdup(skip_spaces(v)));
 266                else if (skip_prefix(buf.buf, "Push:", &v))
 267                        add_push_refspec(remote, xstrdup(skip_spaces(v)));
 268                else if (skip_prefix(buf.buf, "Pull:", &v))
 269                        add_fetch_refspec(remote, xstrdup(skip_spaces(v)));
 270        }
 271        strbuf_release(&buf);
 272        fclose(f);
 273}
 274
 275static void read_branches_file(struct remote *remote)
 276{
 277        char *frag;
 278        struct strbuf buf = STRBUF_INIT;
 279        FILE *f = fopen(git_path("branches/%s", remote->name), "r");
 280
 281        if (!f)
 282                return;
 283
 284        strbuf_getline(&buf, f, '\n');
 285        fclose(f);
 286        strbuf_trim(&buf);
 287        if (!buf.len) {
 288                strbuf_release(&buf);
 289                return;
 290        }
 291
 292        remote->origin = REMOTE_BRANCHES;
 293
 294        /*
 295         * The branches file would have URL and optionally
 296         * #branch specified.  The "master" (or specified) branch is
 297         * fetched and stored in the local branch matching the
 298         * remote name.
 299         */
 300        frag = strchr(buf.buf, '#');
 301        if (frag)
 302                *(frag++) = '\0';
 303        else
 304                frag = "master";
 305
 306        add_url_alias(remote, strbuf_detach(&buf, NULL));
 307        add_fetch_refspec(remote, xstrfmt("refs/heads/%s:refs/heads/%s",
 308                                          frag, remote->name));
 309
 310        /*
 311         * Cogito compatible push: push current HEAD to remote #branch
 312         * (master if missing)
 313         */
 314        add_push_refspec(remote, xstrfmt("HEAD:refs/heads/%s", frag));
 315        remote->fetch_tags = 1; /* always auto-follow */
 316}
 317
 318static int handle_config(const char *key, const char *value, void *cb)
 319{
 320        const char *name;
 321        const char *subkey;
 322        struct remote *remote;
 323        struct branch *branch;
 324        if (starts_with(key, "branch.")) {
 325                name = key + 7;
 326                subkey = strrchr(name, '.');
 327                if (!subkey)
 328                        return 0;
 329                branch = make_branch(name, subkey - name);
 330                if (!strcmp(subkey, ".remote")) {
 331                        return git_config_string(&branch->remote_name, key, value);
 332                } else if (!strcmp(subkey, ".pushremote")) {
 333                        return git_config_string(&branch->pushremote_name, key, value);
 334                } else if (!strcmp(subkey, ".merge")) {
 335                        if (!value)
 336                                return config_error_nonbool(key);
 337                        add_merge(branch, xstrdup(value));
 338                }
 339                return 0;
 340        }
 341        if (starts_with(key, "url.")) {
 342                struct rewrite *rewrite;
 343                name = key + 4;
 344                subkey = strrchr(name, '.');
 345                if (!subkey)
 346                        return 0;
 347                if (!strcmp(subkey, ".insteadof")) {
 348                        rewrite = make_rewrite(&rewrites, name, subkey - name);
 349                        if (!value)
 350                                return config_error_nonbool(key);
 351                        add_instead_of(rewrite, xstrdup(value));
 352                } else if (!strcmp(subkey, ".pushinsteadof")) {
 353                        rewrite = make_rewrite(&rewrites_push, name, subkey - name);
 354                        if (!value)
 355                                return config_error_nonbool(key);
 356                        add_instead_of(rewrite, xstrdup(value));
 357                }
 358        }
 359
 360        if (!starts_with(key,  "remote."))
 361                return 0;
 362        name = key + 7;
 363
 364        /* Handle remote.* variables */
 365        if (!strcmp(name, "pushdefault"))
 366                return git_config_string(&pushremote_name, key, value);
 367
 368        /* Handle remote.<name>.* variables */
 369        if (*name == '/') {
 370                warning("Config remote shorthand cannot begin with '/': %s",
 371                        name);
 372                return 0;
 373        }
 374        subkey = strrchr(name, '.');
 375        if (!subkey)
 376                return 0;
 377        remote = make_remote(name, subkey - name);
 378        remote->origin = REMOTE_CONFIG;
 379        if (!strcmp(subkey, ".mirror"))
 380                remote->mirror = git_config_bool(key, value);
 381        else if (!strcmp(subkey, ".skipdefaultupdate"))
 382                remote->skip_default_update = git_config_bool(key, value);
 383        else if (!strcmp(subkey, ".skipfetchall"))
 384                remote->skip_default_update = git_config_bool(key, value);
 385        else if (!strcmp(subkey, ".prune"))
 386                remote->prune = git_config_bool(key, value);
 387        else if (!strcmp(subkey, ".url")) {
 388                const char *v;
 389                if (git_config_string(&v, key, value))
 390                        return -1;
 391                add_url(remote, v);
 392        } else if (!strcmp(subkey, ".pushurl")) {
 393                const char *v;
 394                if (git_config_string(&v, key, value))
 395                        return -1;
 396                add_pushurl(remote, v);
 397        } else if (!strcmp(subkey, ".push")) {
 398                const char *v;
 399                if (git_config_string(&v, key, value))
 400                        return -1;
 401                add_push_refspec(remote, v);
 402        } else if (!strcmp(subkey, ".fetch")) {
 403                const char *v;
 404                if (git_config_string(&v, key, value))
 405                        return -1;
 406                add_fetch_refspec(remote, v);
 407        } else if (!strcmp(subkey, ".receivepack")) {
 408                const char *v;
 409                if (git_config_string(&v, key, value))
 410                        return -1;
 411                if (!remote->receivepack)
 412                        remote->receivepack = v;
 413                else
 414                        error("more than one receivepack given, using the first");
 415        } else if (!strcmp(subkey, ".uploadpack")) {
 416                const char *v;
 417                if (git_config_string(&v, key, value))
 418                        return -1;
 419                if (!remote->uploadpack)
 420                        remote->uploadpack = v;
 421                else
 422                        error("more than one uploadpack given, using the first");
 423        } else if (!strcmp(subkey, ".tagopt")) {
 424                if (!strcmp(value, "--no-tags"))
 425                        remote->fetch_tags = -1;
 426                else if (!strcmp(value, "--tags"))
 427                        remote->fetch_tags = 2;
 428        } else if (!strcmp(subkey, ".proxy")) {
 429                return git_config_string((const char **)&remote->http_proxy,
 430                                         key, value);
 431        } else if (!strcmp(subkey, ".vcs")) {
 432                return git_config_string(&remote->foreign_vcs, key, value);
 433        }
 434        return 0;
 435}
 436
 437static void alias_all_urls(void)
 438{
 439        int i, j;
 440        for (i = 0; i < remotes_nr; i++) {
 441                int add_pushurl_aliases;
 442                if (!remotes[i])
 443                        continue;
 444                for (j = 0; j < remotes[i]->pushurl_nr; j++) {
 445                        remotes[i]->pushurl[j] = alias_url(remotes[i]->pushurl[j], &rewrites);
 446                }
 447                add_pushurl_aliases = remotes[i]->pushurl_nr == 0;
 448                for (j = 0; j < remotes[i]->url_nr; j++) {
 449                        if (add_pushurl_aliases)
 450                                add_pushurl_alias(remotes[i], remotes[i]->url[j]);
 451                        remotes[i]->url[j] = alias_url(remotes[i]->url[j], &rewrites);
 452                }
 453        }
 454}
 455
 456static void read_config(void)
 457{
 458        static int loaded;
 459        unsigned char sha1[20];
 460        const char *head_ref;
 461        int flag;
 462
 463        if (loaded)
 464                return;
 465        loaded = 1;
 466
 467        current_branch = NULL;
 468        head_ref = resolve_ref_unsafe("HEAD", 0, sha1, &flag);
 469        if (head_ref && (flag & REF_ISSYMREF) &&
 470            skip_prefix(head_ref, "refs/heads/", &head_ref)) {
 471                current_branch = make_branch(head_ref, 0);
 472        }
 473        git_config(handle_config, NULL);
 474        alias_all_urls();
 475}
 476
 477/*
 478 * This function frees a refspec array.
 479 * Warning: code paths should be checked to ensure that the src
 480 *          and dst pointers are always freeable pointers as well
 481 *          as the refspec pointer itself.
 482 */
 483static void free_refspecs(struct refspec *refspec, int nr_refspec)
 484{
 485        int i;
 486
 487        if (!refspec)
 488                return;
 489
 490        for (i = 0; i < nr_refspec; i++) {
 491                free(refspec[i].src);
 492                free(refspec[i].dst);
 493        }
 494        free(refspec);
 495}
 496
 497static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 498{
 499        int i;
 500        struct refspec *rs = xcalloc(nr_refspec, sizeof(*rs));
 501
 502        for (i = 0; i < nr_refspec; i++) {
 503                size_t llen;
 504                int is_glob;
 505                const char *lhs, *rhs;
 506                int flags;
 507
 508                is_glob = 0;
 509
 510                lhs = refspec[i];
 511                if (*lhs == '+') {
 512                        rs[i].force = 1;
 513                        lhs++;
 514                }
 515
 516                rhs = strrchr(lhs, ':');
 517
 518                /*
 519                 * Before going on, special case ":" (or "+:") as a refspec
 520                 * for pushing matching refs.
 521                 */
 522                if (!fetch && rhs == lhs && rhs[1] == '\0') {
 523                        rs[i].matching = 1;
 524                        continue;
 525                }
 526
 527                if (rhs) {
 528                        size_t rlen = strlen(++rhs);
 529                        is_glob = (1 <= rlen && strchr(rhs, '*'));
 530                        rs[i].dst = xstrndup(rhs, rlen);
 531                }
 532
 533                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 534                if (1 <= llen && memchr(lhs, '*', llen)) {
 535                        if ((rhs && !is_glob) || (!rhs && fetch))
 536                                goto invalid;
 537                        is_glob = 1;
 538                } else if (rhs && is_glob) {
 539                        goto invalid;
 540                }
 541
 542                rs[i].pattern = is_glob;
 543                rs[i].src = xstrndup(lhs, llen);
 544                flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 545
 546                if (fetch) {
 547                        unsigned char unused[40];
 548
 549                        /* LHS */
 550                        if (!*rs[i].src)
 551                                ; /* empty is ok; it means "HEAD" */
 552                        else if (llen == 40 && !get_sha1_hex(rs[i].src, unused))
 553                                rs[i].exact_sha1 = 1; /* ok */
 554                        else if (!check_refname_format(rs[i].src, flags))
 555                                ; /* valid looking ref is ok */
 556                        else
 557                                goto invalid;
 558                        /* RHS */
 559                        if (!rs[i].dst)
 560                                ; /* missing is ok; it is the same as empty */
 561                        else if (!*rs[i].dst)
 562                                ; /* empty is ok; it means "do not store" */
 563                        else if (!check_refname_format(rs[i].dst, flags))
 564                                ; /* valid looking ref is ok */
 565                        else
 566                                goto invalid;
 567                } else {
 568                        /*
 569                         * LHS
 570                         * - empty is allowed; it means delete.
 571                         * - when wildcarded, it must be a valid looking ref.
 572                         * - otherwise, it must be an extended SHA-1, but
 573                         *   there is no existing way to validate this.
 574                         */
 575                        if (!*rs[i].src)
 576                                ; /* empty is ok */
 577                        else if (is_glob) {
 578                                if (check_refname_format(rs[i].src, flags))
 579                                        goto invalid;
 580                        }
 581                        else
 582                                ; /* anything goes, for now */
 583                        /*
 584                         * RHS
 585                         * - missing is allowed, but LHS then must be a
 586                         *   valid looking ref.
 587                         * - empty is not allowed.
 588                         * - otherwise it must be a valid looking ref.
 589                         */
 590                        if (!rs[i].dst) {
 591                                if (check_refname_format(rs[i].src, flags))
 592                                        goto invalid;
 593                        } else if (!*rs[i].dst) {
 594                                goto invalid;
 595                        } else {
 596                                if (check_refname_format(rs[i].dst, flags))
 597                                        goto invalid;
 598                        }
 599                }
 600        }
 601        return rs;
 602
 603 invalid:
 604        if (verify) {
 605                /*
 606                 * nr_refspec must be greater than zero and i must be valid
 607                 * since it is only possible to reach this point from within
 608                 * the for loop above.
 609                 */
 610                free_refspecs(rs, i+1);
 611                return NULL;
 612        }
 613        die("Invalid refspec '%s'", refspec[i]);
 614}
 615
 616int valid_fetch_refspec(const char *fetch_refspec_str)
 617{
 618        struct refspec *refspec;
 619
 620        refspec = parse_refspec_internal(1, &fetch_refspec_str, 1, 1);
 621        free_refspecs(refspec, 1);
 622        return !!refspec;
 623}
 624
 625struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 626{
 627        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 628}
 629
 630static struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 631{
 632        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 633}
 634
 635void free_refspec(int nr_refspec, struct refspec *refspec)
 636{
 637        int i;
 638        for (i = 0; i < nr_refspec; i++) {
 639                free(refspec[i].src);
 640                free(refspec[i].dst);
 641        }
 642        free(refspec);
 643}
 644
 645static int valid_remote_nick(const char *name)
 646{
 647        if (!name[0] || is_dot_or_dotdot(name))
 648                return 0;
 649        return !strchr(name, '/'); /* no slash */
 650}
 651
 652const char *remote_for_branch(struct branch *branch, int *explicit)
 653{
 654        if (branch && branch->remote_name) {
 655                if (explicit)
 656                        *explicit = 1;
 657                return branch->remote_name;
 658        }
 659        if (explicit)
 660                *explicit = 0;
 661        return "origin";
 662}
 663
 664const char *pushremote_for_branch(struct branch *branch, int *explicit)
 665{
 666        if (branch && branch->pushremote_name) {
 667                if (explicit)
 668                        *explicit = 1;
 669                return branch->pushremote_name;
 670        }
 671        if (pushremote_name) {
 672                if (explicit)
 673                        *explicit = 1;
 674                return pushremote_name;
 675        }
 676        return remote_for_branch(branch, explicit);
 677}
 678
 679static struct remote *remote_get_1(const char *name,
 680                                   const char *(*get_default)(struct branch *, int *))
 681{
 682        struct remote *ret;
 683        int name_given = 0;
 684
 685        read_config();
 686
 687        if (name)
 688                name_given = 1;
 689        else
 690                name = get_default(current_branch, &name_given);
 691
 692        ret = make_remote(name, 0);
 693        if (valid_remote_nick(name)) {
 694                if (!valid_remote(ret))
 695                        read_remotes_file(ret);
 696                if (!valid_remote(ret))
 697                        read_branches_file(ret);
 698        }
 699        if (name_given && !valid_remote(ret))
 700                add_url_alias(ret, name);
 701        if (!valid_remote(ret))
 702                return NULL;
 703        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 704        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 705        return ret;
 706}
 707
 708struct remote *remote_get(const char *name)
 709{
 710        return remote_get_1(name, remote_for_branch);
 711}
 712
 713struct remote *pushremote_get(const char *name)
 714{
 715        return remote_get_1(name, pushremote_for_branch);
 716}
 717
 718int remote_is_configured(const char *name)
 719{
 720        struct remotes_hash_key lookup;
 721        struct hashmap_entry lookup_entry;
 722        read_config();
 723
 724        init_remotes_hash();
 725        lookup.str = name;
 726        lookup.len = strlen(name);
 727        hashmap_entry_init(&lookup_entry, memhash(name, lookup.len));
 728
 729        return hashmap_get(&remotes_hash, &lookup_entry, &lookup) != NULL;
 730}
 731
 732int for_each_remote(each_remote_fn fn, void *priv)
 733{
 734        int i, result = 0;
 735        read_config();
 736        for (i = 0; i < remotes_nr && !result; i++) {
 737                struct remote *r = remotes[i];
 738                if (!r)
 739                        continue;
 740                if (!r->fetch)
 741                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 742                                                       r->fetch_refspec);
 743                if (!r->push)
 744                        r->push = parse_push_refspec(r->push_refspec_nr,
 745                                                     r->push_refspec);
 746                result = fn(r, priv);
 747        }
 748        return result;
 749}
 750
 751static void handle_duplicate(struct ref *ref1, struct ref *ref2)
 752{
 753        if (strcmp(ref1->name, ref2->name)) {
 754                if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 755                    ref2->fetch_head_status != FETCH_HEAD_IGNORE) {
 756                        die(_("Cannot fetch both %s and %s to %s"),
 757                            ref1->name, ref2->name, ref2->peer_ref->name);
 758                } else if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 759                           ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 760                        warning(_("%s usually tracks %s, not %s"),
 761                                ref2->peer_ref->name, ref2->name, ref1->name);
 762                } else if (ref1->fetch_head_status == FETCH_HEAD_IGNORE &&
 763                           ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 764                        die(_("%s tracks both %s and %s"),
 765                            ref2->peer_ref->name, ref1->name, ref2->name);
 766                } else {
 767                        /*
 768                         * This last possibility doesn't occur because
 769                         * FETCH_HEAD_IGNORE entries always appear at
 770                         * the end of the list.
 771                         */
 772                        die(_("Internal error"));
 773                }
 774        }
 775        free(ref2->peer_ref);
 776        free(ref2);
 777}
 778
 779struct ref *ref_remove_duplicates(struct ref *ref_map)
 780{
 781        struct string_list refs = STRING_LIST_INIT_NODUP;
 782        struct ref *retval = NULL;
 783        struct ref **p = &retval;
 784
 785        while (ref_map) {
 786                struct ref *ref = ref_map;
 787
 788                ref_map = ref_map->next;
 789                ref->next = NULL;
 790
 791                if (!ref->peer_ref) {
 792                        *p = ref;
 793                        p = &ref->next;
 794                } else {
 795                        struct string_list_item *item =
 796                                string_list_insert(&refs, ref->peer_ref->name);
 797
 798                        if (item->util) {
 799                                /* Entry already existed */
 800                                handle_duplicate((struct ref *)item->util, ref);
 801                        } else {
 802                                *p = ref;
 803                                p = &ref->next;
 804                                item->util = ref;
 805                        }
 806                }
 807        }
 808
 809        string_list_clear(&refs, 0);
 810        return retval;
 811}
 812
 813int remote_has_url(struct remote *remote, const char *url)
 814{
 815        int i;
 816        for (i = 0; i < remote->url_nr; i++) {
 817                if (!strcmp(remote->url[i], url))
 818                        return 1;
 819        }
 820        return 0;
 821}
 822
 823static int match_name_with_pattern(const char *key, const char *name,
 824                                   const char *value, char **result)
 825{
 826        const char *kstar = strchr(key, '*');
 827        size_t klen;
 828        size_t ksuffixlen;
 829        size_t namelen;
 830        int ret;
 831        if (!kstar)
 832                die("Key '%s' of pattern had no '*'", key);
 833        klen = kstar - key;
 834        ksuffixlen = strlen(kstar + 1);
 835        namelen = strlen(name);
 836        ret = !strncmp(name, key, klen) && namelen >= klen + ksuffixlen &&
 837                !memcmp(name + namelen - ksuffixlen, kstar + 1, ksuffixlen);
 838        if (ret && value) {
 839                struct strbuf sb = STRBUF_INIT;
 840                const char *vstar = strchr(value, '*');
 841                if (!vstar)
 842                        die("Value '%s' of pattern has no '*'", value);
 843                strbuf_add(&sb, value, vstar - value);
 844                strbuf_add(&sb, name + klen, namelen - klen - ksuffixlen);
 845                strbuf_addstr(&sb, vstar + 1);
 846                *result = strbuf_detach(&sb, NULL);
 847        }
 848        return ret;
 849}
 850
 851static void query_refspecs_multiple(struct refspec *refs, int ref_count, struct refspec *query, struct string_list *results)
 852{
 853        int i;
 854        int find_src = !query->src;
 855
 856        if (find_src && !query->dst)
 857                error("query_refspecs_multiple: need either src or dst");
 858
 859        for (i = 0; i < ref_count; i++) {
 860                struct refspec *refspec = &refs[i];
 861                const char *key = find_src ? refspec->dst : refspec->src;
 862                const char *value = find_src ? refspec->src : refspec->dst;
 863                const char *needle = find_src ? query->dst : query->src;
 864                char **result = find_src ? &query->src : &query->dst;
 865
 866                if (!refspec->dst)
 867                        continue;
 868                if (refspec->pattern) {
 869                        if (match_name_with_pattern(key, needle, value, result))
 870                                string_list_append_nodup(results, *result);
 871                } else if (!strcmp(needle, key)) {
 872                        string_list_append(results, value);
 873                }
 874        }
 875}
 876
 877int query_refspecs(struct refspec *refs, int ref_count, struct refspec *query)
 878{
 879        int i;
 880        int find_src = !query->src;
 881        const char *needle = find_src ? query->dst : query->src;
 882        char **result = find_src ? &query->src : &query->dst;
 883
 884        if (find_src && !query->dst)
 885                return error("query_refspecs: need either src or dst");
 886
 887        for (i = 0; i < ref_count; i++) {
 888                struct refspec *refspec = &refs[i];
 889                const char *key = find_src ? refspec->dst : refspec->src;
 890                const char *value = find_src ? refspec->src : refspec->dst;
 891
 892                if (!refspec->dst)
 893                        continue;
 894                if (refspec->pattern) {
 895                        if (match_name_with_pattern(key, needle, value, result)) {
 896                                query->force = refspec->force;
 897                                return 0;
 898                        }
 899                } else if (!strcmp(needle, key)) {
 900                        *result = xstrdup(value);
 901                        query->force = refspec->force;
 902                        return 0;
 903                }
 904        }
 905        return -1;
 906}
 907
 908char *apply_refspecs(struct refspec *refspecs, int nr_refspec,
 909                     const char *name)
 910{
 911        struct refspec query;
 912
 913        memset(&query, 0, sizeof(struct refspec));
 914        query.src = (char *)name;
 915
 916        if (query_refspecs(refspecs, nr_refspec, &query))
 917                return NULL;
 918
 919        return query.dst;
 920}
 921
 922int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 923{
 924        return query_refspecs(remote->fetch, remote->fetch_refspec_nr, refspec);
 925}
 926
 927static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 928                const char *name)
 929{
 930        size_t len = strlen(name);
 931        struct ref *ref = xcalloc(1, sizeof(struct ref) + prefixlen + len + 1);
 932        memcpy(ref->name, prefix, prefixlen);
 933        memcpy(ref->name + prefixlen, name, len);
 934        return ref;
 935}
 936
 937struct ref *alloc_ref(const char *name)
 938{
 939        return alloc_ref_with_prefix("", 0, name);
 940}
 941
 942struct ref *copy_ref(const struct ref *ref)
 943{
 944        struct ref *cpy;
 945        size_t len;
 946        if (!ref)
 947                return NULL;
 948        len = strlen(ref->name);
 949        cpy = xmalloc(sizeof(struct ref) + len + 1);
 950        memcpy(cpy, ref, sizeof(struct ref) + len + 1);
 951        cpy->next = NULL;
 952        cpy->symref = xstrdup_or_null(ref->symref);
 953        cpy->remote_status = xstrdup_or_null(ref->remote_status);
 954        cpy->peer_ref = copy_ref(ref->peer_ref);
 955        return cpy;
 956}
 957
 958struct ref *copy_ref_list(const struct ref *ref)
 959{
 960        struct ref *ret = NULL;
 961        struct ref **tail = &ret;
 962        while (ref) {
 963                *tail = copy_ref(ref);
 964                ref = ref->next;
 965                tail = &((*tail)->next);
 966        }
 967        return ret;
 968}
 969
 970static void free_ref(struct ref *ref)
 971{
 972        if (!ref)
 973                return;
 974        free_ref(ref->peer_ref);
 975        free(ref->remote_status);
 976        free(ref->symref);
 977        free(ref);
 978}
 979
 980void free_refs(struct ref *ref)
 981{
 982        struct ref *next;
 983        while (ref) {
 984                next = ref->next;
 985                free_ref(ref);
 986                ref = next;
 987        }
 988}
 989
 990int ref_compare_name(const void *va, const void *vb)
 991{
 992        const struct ref *a = va, *b = vb;
 993        return strcmp(a->name, b->name);
 994}
 995
 996static void *ref_list_get_next(const void *a)
 997{
 998        return ((const struct ref *)a)->next;
 999}
1000
1001static void ref_list_set_next(void *a, void *next)
1002{
1003        ((struct ref *)a)->next = next;
1004}
1005
1006void sort_ref_list(struct ref **l, int (*cmp)(const void *, const void *))
1007{
1008        *l = llist_mergesort(*l, ref_list_get_next, ref_list_set_next, cmp);
1009}
1010
1011int count_refspec_match(const char *pattern,
1012                        struct ref *refs,
1013                        struct ref **matched_ref)
1014{
1015        int patlen = strlen(pattern);
1016        struct ref *matched_weak = NULL;
1017        struct ref *matched = NULL;
1018        int weak_match = 0;
1019        int match = 0;
1020
1021        for (weak_match = match = 0; refs; refs = refs->next) {
1022                char *name = refs->name;
1023                int namelen = strlen(name);
1024
1025                if (!refname_match(pattern, name))
1026                        continue;
1027
1028                /* A match is "weak" if it is with refs outside
1029                 * heads or tags, and did not specify the pattern
1030                 * in full (e.g. "refs/remotes/origin/master") or at
1031                 * least from the toplevel (e.g. "remotes/origin/master");
1032                 * otherwise "git push $URL master" would result in
1033                 * ambiguity between remotes/origin/master and heads/master
1034                 * at the remote site.
1035                 */
1036                if (namelen != patlen &&
1037                    patlen != namelen - 5 &&
1038                    !starts_with(name, "refs/heads/") &&
1039                    !starts_with(name, "refs/tags/")) {
1040                        /* We want to catch the case where only weak
1041                         * matches are found and there are multiple
1042                         * matches, and where more than one strong
1043                         * matches are found, as ambiguous.  One
1044                         * strong match with zero or more weak matches
1045                         * are acceptable as a unique match.
1046                         */
1047                        matched_weak = refs;
1048                        weak_match++;
1049                }
1050                else {
1051                        matched = refs;
1052                        match++;
1053                }
1054        }
1055        if (!matched) {
1056                if (matched_ref)
1057                        *matched_ref = matched_weak;
1058                return weak_match;
1059        }
1060        else {
1061                if (matched_ref)
1062                        *matched_ref = matched;
1063                return match;
1064        }
1065}
1066
1067static void tail_link_ref(struct ref *ref, struct ref ***tail)
1068{
1069        **tail = ref;
1070        while (ref->next)
1071                ref = ref->next;
1072        *tail = &ref->next;
1073}
1074
1075static struct ref *alloc_delete_ref(void)
1076{
1077        struct ref *ref = alloc_ref("(delete)");
1078        hashclr(ref->new_sha1);
1079        return ref;
1080}
1081
1082static int try_explicit_object_name(const char *name,
1083                                    struct ref **match)
1084{
1085        unsigned char sha1[20];
1086
1087        if (!*name) {
1088                if (match)
1089                        *match = alloc_delete_ref();
1090                return 0;
1091        }
1092
1093        if (get_sha1(name, sha1))
1094                return -1;
1095
1096        if (match) {
1097                *match = alloc_ref(name);
1098                hashcpy((*match)->new_sha1, sha1);
1099        }
1100        return 0;
1101}
1102
1103static struct ref *make_linked_ref(const char *name, struct ref ***tail)
1104{
1105        struct ref *ret = alloc_ref(name);
1106        tail_link_ref(ret, tail);
1107        return ret;
1108}
1109
1110static char *guess_ref(const char *name, struct ref *peer)
1111{
1112        struct strbuf buf = STRBUF_INIT;
1113        unsigned char sha1[20];
1114
1115        const char *r = resolve_ref_unsafe(peer->name, RESOLVE_REF_READING,
1116                                           sha1, NULL);
1117        if (!r)
1118                return NULL;
1119
1120        if (starts_with(r, "refs/heads/"))
1121                strbuf_addstr(&buf, "refs/heads/");
1122        else if (starts_with(r, "refs/tags/"))
1123                strbuf_addstr(&buf, "refs/tags/");
1124        else
1125                return NULL;
1126
1127        strbuf_addstr(&buf, name);
1128        return strbuf_detach(&buf, NULL);
1129}
1130
1131static int match_explicit_lhs(struct ref *src,
1132                              struct refspec *rs,
1133                              struct ref **match,
1134                              int *allocated_match)
1135{
1136        switch (count_refspec_match(rs->src, src, match)) {
1137        case 1:
1138                if (allocated_match)
1139                        *allocated_match = 0;
1140                return 0;
1141        case 0:
1142                /* The source could be in the get_sha1() format
1143                 * not a reference name.  :refs/other is a
1144                 * way to delete 'other' ref at the remote end.
1145                 */
1146                if (try_explicit_object_name(rs->src, match) < 0)
1147                        return error("src refspec %s does not match any.", rs->src);
1148                if (allocated_match)
1149                        *allocated_match = 1;
1150                return 0;
1151        default:
1152                return error("src refspec %s matches more than one.", rs->src);
1153        }
1154}
1155
1156static int match_explicit(struct ref *src, struct ref *dst,
1157                          struct ref ***dst_tail,
1158                          struct refspec *rs)
1159{
1160        struct ref *matched_src, *matched_dst;
1161        int allocated_src;
1162
1163        const char *dst_value = rs->dst;
1164        char *dst_guess;
1165
1166        if (rs->pattern || rs->matching)
1167                return 0;
1168
1169        matched_src = matched_dst = NULL;
1170        if (match_explicit_lhs(src, rs, &matched_src, &allocated_src) < 0)
1171                return -1;
1172
1173        if (!dst_value) {
1174                unsigned char sha1[20];
1175                int flag;
1176
1177                dst_value = resolve_ref_unsafe(matched_src->name,
1178                                               RESOLVE_REF_READING,
1179                                               sha1, &flag);
1180                if (!dst_value ||
1181                    ((flag & REF_ISSYMREF) &&
1182                     !starts_with(dst_value, "refs/heads/")))
1183                        die("%s cannot be resolved to branch.",
1184                            matched_src->name);
1185        }
1186
1187        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
1188        case 1:
1189                break;
1190        case 0:
1191                if (starts_with(dst_value, "refs/"))
1192                        matched_dst = make_linked_ref(dst_value, dst_tail);
1193                else if (is_null_sha1(matched_src->new_sha1))
1194                        error("unable to delete '%s': remote ref does not exist",
1195                              dst_value);
1196                else if ((dst_guess = guess_ref(dst_value, matched_src)))
1197                        matched_dst = make_linked_ref(dst_guess, dst_tail);
1198                else
1199                        error("unable to push to unqualified destination: %s\n"
1200                              "The destination refspec neither matches an "
1201                              "existing ref on the remote nor\n"
1202                              "begins with refs/, and we are unable to "
1203                              "guess a prefix based on the source ref.",
1204                              dst_value);
1205                break;
1206        default:
1207                matched_dst = NULL;
1208                error("dst refspec %s matches more than one.",
1209                      dst_value);
1210                break;
1211        }
1212        if (!matched_dst)
1213                return -1;
1214        if (matched_dst->peer_ref)
1215                return error("dst ref %s receives from more than one src.",
1216                      matched_dst->name);
1217        else {
1218                matched_dst->peer_ref = allocated_src ?
1219                                        matched_src :
1220                                        copy_ref(matched_src);
1221                matched_dst->force = rs->force;
1222        }
1223        return 0;
1224}
1225
1226static int match_explicit_refs(struct ref *src, struct ref *dst,
1227                               struct ref ***dst_tail, struct refspec *rs,
1228                               int rs_nr)
1229{
1230        int i, errs;
1231        for (i = errs = 0; i < rs_nr; i++)
1232                errs += match_explicit(src, dst, dst_tail, &rs[i]);
1233        return errs;
1234}
1235
1236static char *get_ref_match(const struct refspec *rs, int rs_nr, const struct ref *ref,
1237                int send_mirror, int direction, const struct refspec **ret_pat)
1238{
1239        const struct refspec *pat;
1240        char *name;
1241        int i;
1242        int matching_refs = -1;
1243        for (i = 0; i < rs_nr; i++) {
1244                if (rs[i].matching &&
1245                    (matching_refs == -1 || rs[i].force)) {
1246                        matching_refs = i;
1247                        continue;
1248                }
1249
1250                if (rs[i].pattern) {
1251                        const char *dst_side = rs[i].dst ? rs[i].dst : rs[i].src;
1252                        int match;
1253                        if (direction == FROM_SRC)
1254                                match = match_name_with_pattern(rs[i].src, ref->name, dst_side, &name);
1255                        else
1256                                match = match_name_with_pattern(dst_side, ref->name, rs[i].src, &name);
1257                        if (match) {
1258                                matching_refs = i;
1259                                break;
1260                        }
1261                }
1262        }
1263        if (matching_refs == -1)
1264                return NULL;
1265
1266        pat = rs + matching_refs;
1267        if (pat->matching) {
1268                /*
1269                 * "matching refs"; traditionally we pushed everything
1270                 * including refs outside refs/heads/ hierarchy, but
1271                 * that does not make much sense these days.
1272                 */
1273                if (!send_mirror && !starts_with(ref->name, "refs/heads/"))
1274                        return NULL;
1275                name = xstrdup(ref->name);
1276        }
1277        if (ret_pat)
1278                *ret_pat = pat;
1279        return name;
1280}
1281
1282static struct ref **tail_ref(struct ref **head)
1283{
1284        struct ref **tail = head;
1285        while (*tail)
1286                tail = &((*tail)->next);
1287        return tail;
1288}
1289
1290struct tips {
1291        struct commit **tip;
1292        int nr, alloc;
1293};
1294
1295static void add_to_tips(struct tips *tips, const unsigned char *sha1)
1296{
1297        struct commit *commit;
1298
1299        if (is_null_sha1(sha1))
1300                return;
1301        commit = lookup_commit_reference_gently(sha1, 1);
1302        if (!commit || (commit->object.flags & TMP_MARK))
1303                return;
1304        commit->object.flags |= TMP_MARK;
1305        ALLOC_GROW(tips->tip, tips->nr + 1, tips->alloc);
1306        tips->tip[tips->nr++] = commit;
1307}
1308
1309static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***dst_tail)
1310{
1311        struct string_list dst_tag = STRING_LIST_INIT_NODUP;
1312        struct string_list src_tag = STRING_LIST_INIT_NODUP;
1313        struct string_list_item *item;
1314        struct ref *ref;
1315        struct tips sent_tips;
1316
1317        /*
1318         * Collect everything we know they would have at the end of
1319         * this push, and collect all tags they have.
1320         */
1321        memset(&sent_tips, 0, sizeof(sent_tips));
1322        for (ref = *dst; ref; ref = ref->next) {
1323                if (ref->peer_ref &&
1324                    !is_null_sha1(ref->peer_ref->new_sha1))
1325                        add_to_tips(&sent_tips, ref->peer_ref->new_sha1);
1326                else
1327                        add_to_tips(&sent_tips, ref->old_sha1);
1328                if (starts_with(ref->name, "refs/tags/"))
1329                        string_list_append(&dst_tag, ref->name);
1330        }
1331        clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
1332
1333        string_list_sort(&dst_tag);
1334
1335        /* Collect tags they do not have. */
1336        for (ref = src; ref; ref = ref->next) {
1337                if (!starts_with(ref->name, "refs/tags/"))
1338                        continue; /* not a tag */
1339                if (string_list_has_string(&dst_tag, ref->name))
1340                        continue; /* they already have it */
1341                if (sha1_object_info(ref->new_sha1, NULL) != OBJ_TAG)
1342                        continue; /* be conservative */
1343                item = string_list_append(&src_tag, ref->name);
1344                item->util = ref;
1345        }
1346        string_list_clear(&dst_tag, 0);
1347
1348        /*
1349         * At this point, src_tag lists tags that are missing from
1350         * dst, and sent_tips lists the tips we are pushing or those
1351         * that we know they already have. An element in the src_tag
1352         * that is an ancestor of any of the sent_tips needs to be
1353         * sent to the other side.
1354         */
1355        if (sent_tips.nr) {
1356                for_each_string_list_item(item, &src_tag) {
1357                        struct ref *ref = item->util;
1358                        struct ref *dst_ref;
1359                        struct commit *commit;
1360
1361                        if (is_null_sha1(ref->new_sha1))
1362                                continue;
1363                        commit = lookup_commit_reference_gently(ref->new_sha1, 1);
1364                        if (!commit)
1365                                /* not pushing a commit, which is not an error */
1366                                continue;
1367
1368                        /*
1369                         * Is this tag, which they do not have, reachable from
1370                         * any of the commits we are sending?
1371                         */
1372                        if (!in_merge_bases_many(commit, sent_tips.nr, sent_tips.tip))
1373                                continue;
1374
1375                        /* Add it in */
1376                        dst_ref = make_linked_ref(ref->name, dst_tail);
1377                        hashcpy(dst_ref->new_sha1, ref->new_sha1);
1378                        dst_ref->peer_ref = copy_ref(ref);
1379                }
1380        }
1381        string_list_clear(&src_tag, 0);
1382        free(sent_tips.tip);
1383}
1384
1385struct ref *find_ref_by_name(const struct ref *list, const char *name)
1386{
1387        for ( ; list; list = list->next)
1388                if (!strcmp(list->name, name))
1389                        return (struct ref *)list;
1390        return NULL;
1391}
1392
1393static void prepare_ref_index(struct string_list *ref_index, struct ref *ref)
1394{
1395        for ( ; ref; ref = ref->next)
1396                string_list_append_nodup(ref_index, ref->name)->util = ref;
1397
1398        string_list_sort(ref_index);
1399}
1400
1401/*
1402 * Given only the set of local refs, sanity-check the set of push
1403 * refspecs. We can't catch all errors that match_push_refs would,
1404 * but we can catch some errors early before even talking to the
1405 * remote side.
1406 */
1407int check_push_refs(struct ref *src, int nr_refspec, const char **refspec_names)
1408{
1409        struct refspec *refspec = parse_push_refspec(nr_refspec, refspec_names);
1410        int ret = 0;
1411        int i;
1412
1413        for (i = 0; i < nr_refspec; i++) {
1414                struct refspec *rs = refspec + i;
1415
1416                if (rs->pattern || rs->matching)
1417                        continue;
1418
1419                ret |= match_explicit_lhs(src, rs, NULL, NULL);
1420        }
1421
1422        free_refspec(nr_refspec, refspec);
1423        return ret;
1424}
1425
1426/*
1427 * Given the set of refs the local repository has, the set of refs the
1428 * remote repository has, and the refspec used for push, determine
1429 * what remote refs we will update and with what value by setting
1430 * peer_ref (which object is being pushed) and force (if the push is
1431 * forced) in elements of "dst". The function may add new elements to
1432 * dst (e.g. pushing to a new branch, done in match_explicit_refs).
1433 */
1434int match_push_refs(struct ref *src, struct ref **dst,
1435                    int nr_refspec, const char **refspec, int flags)
1436{
1437        struct refspec *rs;
1438        int send_all = flags & MATCH_REFS_ALL;
1439        int send_mirror = flags & MATCH_REFS_MIRROR;
1440        int send_prune = flags & MATCH_REFS_PRUNE;
1441        int errs;
1442        static const char *default_refspec[] = { ":", NULL };
1443        struct ref *ref, **dst_tail = tail_ref(dst);
1444        struct string_list dst_ref_index = STRING_LIST_INIT_NODUP;
1445
1446        if (!nr_refspec) {
1447                nr_refspec = 1;
1448                refspec = default_refspec;
1449        }
1450        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1451        errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
1452
1453        /* pick the remainder */
1454        for (ref = src; ref; ref = ref->next) {
1455                struct string_list_item *dst_item;
1456                struct ref *dst_peer;
1457                const struct refspec *pat = NULL;
1458                char *dst_name;
1459
1460                dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
1461                if (!dst_name)
1462                        continue;
1463
1464                if (!dst_ref_index.nr)
1465                        prepare_ref_index(&dst_ref_index, *dst);
1466
1467                dst_item = string_list_lookup(&dst_ref_index, dst_name);
1468                dst_peer = dst_item ? dst_item->util : NULL;
1469                if (dst_peer) {
1470                        if (dst_peer->peer_ref)
1471                                /* We're already sending something to this ref. */
1472                                goto free_name;
1473                } else {
1474                        if (pat->matching && !(send_all || send_mirror))
1475                                /*
1476                                 * Remote doesn't have it, and we have no
1477                                 * explicit pattern, and we don't have
1478                                 * --all or --mirror.
1479                                 */
1480                                goto free_name;
1481
1482                        /* Create a new one and link it */
1483                        dst_peer = make_linked_ref(dst_name, &dst_tail);
1484                        hashcpy(dst_peer->new_sha1, ref->new_sha1);
1485                        string_list_insert(&dst_ref_index,
1486                                dst_peer->name)->util = dst_peer;
1487                }
1488                dst_peer->peer_ref = copy_ref(ref);
1489                dst_peer->force = pat->force;
1490        free_name:
1491                free(dst_name);
1492        }
1493
1494        string_list_clear(&dst_ref_index, 0);
1495
1496        if (flags & MATCH_REFS_FOLLOW_TAGS)
1497                add_missing_tags(src, dst, &dst_tail);
1498
1499        if (send_prune) {
1500                struct string_list src_ref_index = STRING_LIST_INIT_NODUP;
1501                /* check for missing refs on the remote */
1502                for (ref = *dst; ref; ref = ref->next) {
1503                        char *src_name;
1504
1505                        if (ref->peer_ref)
1506                                /* We're already sending something to this ref. */
1507                                continue;
1508
1509                        src_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_DST, NULL);
1510                        if (src_name) {
1511                                if (!src_ref_index.nr)
1512                                        prepare_ref_index(&src_ref_index, src);
1513                                if (!string_list_has_string(&src_ref_index,
1514                                            src_name))
1515                                        ref->peer_ref = alloc_delete_ref();
1516                                free(src_name);
1517                        }
1518                }
1519                string_list_clear(&src_ref_index, 0);
1520        }
1521        if (errs)
1522                return -1;
1523        return 0;
1524}
1525
1526void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
1527                             int force_update)
1528{
1529        struct ref *ref;
1530
1531        for (ref = remote_refs; ref; ref = ref->next) {
1532                int force_ref_update = ref->force || force_update;
1533                int reject_reason = 0;
1534
1535                if (ref->peer_ref)
1536                        hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
1537                else if (!send_mirror)
1538                        continue;
1539
1540                ref->deletion = is_null_sha1(ref->new_sha1);
1541                if (!ref->deletion &&
1542                        !hashcmp(ref->old_sha1, ref->new_sha1)) {
1543                        ref->status = REF_STATUS_UPTODATE;
1544                        continue;
1545                }
1546
1547                /*
1548                 * Bypass the usual "must fast-forward" check but
1549                 * replace it with a weaker "the old value must be
1550                 * this value we observed".  If the remote ref has
1551                 * moved and is now different from what we expect,
1552                 * reject any push.
1553                 *
1554                 * It also is an error if the user told us to check
1555                 * with the remote-tracking branch to find the value
1556                 * to expect, but we did not have such a tracking
1557                 * branch.
1558                 */
1559                if (ref->expect_old_sha1) {
1560                        if (ref->expect_old_no_trackback ||
1561                            hashcmp(ref->old_sha1, ref->old_sha1_expect))
1562                                reject_reason = REF_STATUS_REJECT_STALE;
1563                }
1564
1565                /*
1566                 * The usual "must fast-forward" rules.
1567                 *
1568                 * Decide whether an individual refspec A:B can be
1569                 * pushed.  The push will succeed if any of the
1570                 * following are true:
1571                 *
1572                 * (1) the remote reference B does not exist
1573                 *
1574                 * (2) the remote reference B is being removed (i.e.,
1575                 *     pushing :B where no source is specified)
1576                 *
1577                 * (3) the destination is not under refs/tags/, and
1578                 *     if the old and new value is a commit, the new
1579                 *     is a descendant of the old.
1580                 *
1581                 * (4) it is forced using the +A:B notation, or by
1582                 *     passing the --force argument
1583                 */
1584
1585                else if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
1586                        if (starts_with(ref->name, "refs/tags/"))
1587                                reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
1588                        else if (!has_sha1_file(ref->old_sha1))
1589                                reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
1590                        else if (!lookup_commit_reference_gently(ref->old_sha1, 1) ||
1591                                 !lookup_commit_reference_gently(ref->new_sha1, 1))
1592                                reject_reason = REF_STATUS_REJECT_NEEDS_FORCE;
1593                        else if (!ref_newer(ref->new_sha1, ref->old_sha1))
1594                                reject_reason = REF_STATUS_REJECT_NONFASTFORWARD;
1595                }
1596
1597                /*
1598                 * "--force" will defeat any rejection implemented
1599                 * by the rules above.
1600                 */
1601                if (!force_ref_update)
1602                        ref->status = reject_reason;
1603                else if (reject_reason)
1604                        ref->forced_update = 1;
1605        }
1606}
1607
1608static void set_merge(struct branch *ret)
1609{
1610        struct remote *remote;
1611        char *ref;
1612        unsigned char sha1[20];
1613        int i;
1614
1615        if (!ret)
1616                return; /* no branch */
1617        if (ret->merge)
1618                return; /* already run */
1619        if (!ret->remote_name || !ret->merge_nr) {
1620                /*
1621                 * no merge config; let's make sure we don't confuse callers
1622                 * with a non-zero merge_nr but a NULL merge
1623                 */
1624                ret->merge_nr = 0;
1625                return;
1626        }
1627
1628        remote = remote_get(ret->remote_name);
1629
1630        ret->merge = xcalloc(ret->merge_nr, sizeof(*ret->merge));
1631        for (i = 0; i < ret->merge_nr; i++) {
1632                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1633                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1634                if (!remote_find_tracking(remote, ret->merge[i]) ||
1635                    strcmp(ret->remote_name, "."))
1636                        continue;
1637                if (dwim_ref(ret->merge_name[i], strlen(ret->merge_name[i]),
1638                             sha1, &ref) == 1)
1639                        ret->merge[i]->dst = ref;
1640                else
1641                        ret->merge[i]->dst = xstrdup(ret->merge_name[i]);
1642        }
1643}
1644
1645struct branch *branch_get(const char *name)
1646{
1647        struct branch *ret;
1648
1649        read_config();
1650        if (!name || !*name || !strcmp(name, "HEAD"))
1651                ret = current_branch;
1652        else
1653                ret = make_branch(name, 0);
1654        set_merge(ret);
1655        return ret;
1656}
1657
1658int branch_has_merge_config(struct branch *branch)
1659{
1660        return branch && !!branch->merge;
1661}
1662
1663int branch_merge_matches(struct branch *branch,
1664                                 int i,
1665                                 const char *refname)
1666{
1667        if (!branch || i < 0 || i >= branch->merge_nr)
1668                return 0;
1669        return refname_match(branch->merge[i]->src, refname);
1670}
1671
1672__attribute((format (printf,2,3)))
1673static const char *error_buf(struct strbuf *err, const char *fmt, ...)
1674{
1675        if (err) {
1676                va_list ap;
1677                va_start(ap, fmt);
1678                strbuf_vaddf(err, fmt, ap);
1679                va_end(ap);
1680        }
1681        return NULL;
1682}
1683
1684const char *branch_get_upstream(struct branch *branch, struct strbuf *err)
1685{
1686        if (!branch)
1687                return error_buf(err, _("HEAD does not point to a branch"));
1688
1689        if (!branch->merge || !branch->merge[0]) {
1690                /*
1691                 * no merge config; is it because the user didn't define any,
1692                 * or because it is not a real branch, and get_branch
1693                 * auto-vivified it?
1694                 */
1695                if (!ref_exists(branch->refname))
1696                        return error_buf(err, _("no such branch: '%s'"),
1697                                         branch->name);
1698                return error_buf(err,
1699                                 _("no upstream configured for branch '%s'"),
1700                                 branch->name);
1701        }
1702
1703        if (!branch->merge[0]->dst)
1704                return error_buf(err,
1705                                 _("upstream branch '%s' not stored as a remote-tracking branch"),
1706                                 branch->merge[0]->src);
1707
1708        return branch->merge[0]->dst;
1709}
1710
1711static const char *tracking_for_push_dest(struct remote *remote,
1712                                          const char *refname,
1713                                          struct strbuf *err)
1714{
1715        char *ret;
1716
1717        ret = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
1718        if (!ret)
1719                return error_buf(err,
1720                                 _("push destination '%s' on remote '%s' has no local tracking branch"),
1721                                 refname, remote->name);
1722        return ret;
1723}
1724
1725static const char *branch_get_push_1(struct branch *branch, struct strbuf *err)
1726{
1727        struct remote *remote;
1728
1729        if (!branch)
1730                return error_buf(err, _("HEAD does not point to a branch"));
1731
1732        remote = remote_get(pushremote_for_branch(branch, NULL));
1733        if (!remote)
1734                return error_buf(err,
1735                                 _("branch '%s' has no remote for pushing"),
1736                                 branch->name);
1737
1738        if (remote->push_refspec_nr) {
1739                char *dst;
1740                const char *ret;
1741
1742                dst = apply_refspecs(remote->push, remote->push_refspec_nr,
1743                                     branch->refname);
1744                if (!dst)
1745                        return error_buf(err,
1746                                         _("push refspecs for '%s' do not include '%s'"),
1747                                         remote->name, branch->name);
1748
1749                ret = tracking_for_push_dest(remote, dst, err);
1750                free(dst);
1751                return ret;
1752        }
1753
1754        if (remote->mirror)
1755                return tracking_for_push_dest(remote, branch->refname, err);
1756
1757        switch (push_default) {
1758        case PUSH_DEFAULT_NOTHING:
1759                return error_buf(err, _("push has no destination (push.default is 'nothing')"));
1760
1761        case PUSH_DEFAULT_MATCHING:
1762        case PUSH_DEFAULT_CURRENT:
1763                return tracking_for_push_dest(remote, branch->refname, err);
1764
1765        case PUSH_DEFAULT_UPSTREAM:
1766                return branch_get_upstream(branch, err);
1767
1768        case PUSH_DEFAULT_UNSPECIFIED:
1769        case PUSH_DEFAULT_SIMPLE:
1770                {
1771                        const char *up, *cur;
1772
1773                        up = branch_get_upstream(branch, err);
1774                        if (!up)
1775                                return NULL;
1776                        cur = tracking_for_push_dest(remote, branch->refname, err);
1777                        if (!cur)
1778                                return NULL;
1779                        if (strcmp(cur, up))
1780                                return error_buf(err,
1781                                                 _("cannot resolve 'simple' push to a single destination"));
1782                        return cur;
1783                }
1784        }
1785
1786        die("BUG: unhandled push situation");
1787}
1788
1789const char *branch_get_push(struct branch *branch, struct strbuf *err)
1790{
1791        if (!branch->push_tracking_ref)
1792                branch->push_tracking_ref = branch_get_push_1(branch, err);
1793        return branch->push_tracking_ref;
1794}
1795
1796static int ignore_symref_update(const char *refname)
1797{
1798        unsigned char sha1[20];
1799        int flag;
1800
1801        if (!resolve_ref_unsafe(refname, 0, sha1, &flag))
1802                return 0; /* non-existing refs are OK */
1803        return (flag & REF_ISSYMREF);
1804}
1805
1806/*
1807 * Create and return a list of (struct ref) consisting of copies of
1808 * each remote_ref that matches refspec.  refspec must be a pattern.
1809 * Fill in the copies' peer_ref to describe the local tracking refs to
1810 * which they map.  Omit any references that would map to an existing
1811 * local symbolic ref.
1812 */
1813static struct ref *get_expanded_map(const struct ref *remote_refs,
1814                                    const struct refspec *refspec)
1815{
1816        const struct ref *ref;
1817        struct ref *ret = NULL;
1818        struct ref **tail = &ret;
1819
1820        for (ref = remote_refs; ref; ref = ref->next) {
1821                char *expn_name = NULL;
1822
1823                if (strchr(ref->name, '^'))
1824                        continue; /* a dereference item */
1825                if (match_name_with_pattern(refspec->src, ref->name,
1826                                            refspec->dst, &expn_name) &&
1827                    !ignore_symref_update(expn_name)) {
1828                        struct ref *cpy = copy_ref(ref);
1829
1830                        cpy->peer_ref = alloc_ref(expn_name);
1831                        if (refspec->force)
1832                                cpy->peer_ref->force = 1;
1833                        *tail = cpy;
1834                        tail = &cpy->next;
1835                }
1836                free(expn_name);
1837        }
1838
1839        return ret;
1840}
1841
1842static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1843{
1844        const struct ref *ref;
1845        for (ref = refs; ref; ref = ref->next) {
1846                if (refname_match(name, ref->name))
1847                        return ref;
1848        }
1849        return NULL;
1850}
1851
1852struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1853{
1854        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1855
1856        if (!ref)
1857                return NULL;
1858
1859        return copy_ref(ref);
1860}
1861
1862static struct ref *get_local_ref(const char *name)
1863{
1864        if (!name || name[0] == '\0')
1865                return NULL;
1866
1867        if (starts_with(name, "refs/"))
1868                return alloc_ref(name);
1869
1870        if (starts_with(name, "heads/") ||
1871            starts_with(name, "tags/") ||
1872            starts_with(name, "remotes/"))
1873                return alloc_ref_with_prefix("refs/", 5, name);
1874
1875        return alloc_ref_with_prefix("refs/heads/", 11, name);
1876}
1877
1878int get_fetch_map(const struct ref *remote_refs,
1879                  const struct refspec *refspec,
1880                  struct ref ***tail,
1881                  int missing_ok)
1882{
1883        struct ref *ref_map, **rmp;
1884
1885        if (refspec->pattern) {
1886                ref_map = get_expanded_map(remote_refs, refspec);
1887        } else {
1888                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1889
1890                if (refspec->exact_sha1) {
1891                        ref_map = alloc_ref(name);
1892                        get_sha1_hex(name, ref_map->old_sha1);
1893                } else {
1894                        ref_map = get_remote_ref(remote_refs, name);
1895                }
1896                if (!missing_ok && !ref_map)
1897                        die("Couldn't find remote ref %s", name);
1898                if (ref_map) {
1899                        ref_map->peer_ref = get_local_ref(refspec->dst);
1900                        if (ref_map->peer_ref && refspec->force)
1901                                ref_map->peer_ref->force = 1;
1902                }
1903        }
1904
1905        for (rmp = &ref_map; *rmp; ) {
1906                if ((*rmp)->peer_ref) {
1907                        if (!starts_with((*rmp)->peer_ref->name, "refs/") ||
1908                            check_refname_format((*rmp)->peer_ref->name, 0)) {
1909                                struct ref *ignore = *rmp;
1910                                error("* Ignoring funny ref '%s' locally",
1911                                      (*rmp)->peer_ref->name);
1912                                *rmp = (*rmp)->next;
1913                                free(ignore->peer_ref);
1914                                free(ignore);
1915                                continue;
1916                        }
1917                }
1918                rmp = &((*rmp)->next);
1919        }
1920
1921        if (ref_map)
1922                tail_link_ref(ref_map, tail);
1923
1924        return 0;
1925}
1926
1927int resolve_remote_symref(struct ref *ref, struct ref *list)
1928{
1929        if (!ref->symref)
1930                return 0;
1931        for (; list; list = list->next)
1932                if (!strcmp(ref->symref, list->name)) {
1933                        hashcpy(ref->old_sha1, list->old_sha1);
1934                        return 0;
1935                }
1936        return 1;
1937}
1938
1939static void unmark_and_free(struct commit_list *list, unsigned int mark)
1940{
1941        while (list) {
1942                struct commit *commit = pop_commit(&list);
1943                commit->object.flags &= ~mark;
1944        }
1945}
1946
1947int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
1948{
1949        struct object *o;
1950        struct commit *old, *new;
1951        struct commit_list *list, *used;
1952        int found = 0;
1953
1954        /*
1955         * Both new and old must be commit-ish and new is descendant of
1956         * old.  Otherwise we require --force.
1957         */
1958        o = deref_tag(parse_object(old_sha1), NULL, 0);
1959        if (!o || o->type != OBJ_COMMIT)
1960                return 0;
1961        old = (struct commit *) o;
1962
1963        o = deref_tag(parse_object(new_sha1), NULL, 0);
1964        if (!o || o->type != OBJ_COMMIT)
1965                return 0;
1966        new = (struct commit *) o;
1967
1968        if (parse_commit(new) < 0)
1969                return 0;
1970
1971        used = list = NULL;
1972        commit_list_insert(new, &list);
1973        while (list) {
1974                new = pop_most_recent_commit(&list, TMP_MARK);
1975                commit_list_insert(new, &used);
1976                if (new == old) {
1977                        found = 1;
1978                        break;
1979                }
1980        }
1981        unmark_and_free(list, TMP_MARK);
1982        unmark_and_free(used, TMP_MARK);
1983        return found;
1984}
1985
1986/*
1987 * Compare a branch with its upstream, and save their differences (number
1988 * of commits) in *num_ours and *num_theirs. The name of the upstream branch
1989 * (or NULL if no upstream is defined) is returned via *upstream_name, if it
1990 * is not itself NULL.
1991 *
1992 * Returns -1 if num_ours and num_theirs could not be filled in (e.g., no
1993 * upstream defined, or ref does not exist), 0 otherwise.
1994 */
1995int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs,
1996                       const char **upstream_name)
1997{
1998        unsigned char sha1[20];
1999        struct commit *ours, *theirs;
2000        struct rev_info revs;
2001        const char *base;
2002        struct argv_array argv = ARGV_ARRAY_INIT;
2003
2004        /* Cannot stat unless we are marked to build on top of somebody else. */
2005        base = branch_get_upstream(branch, NULL);
2006        if (upstream_name)
2007                *upstream_name = base;
2008        if (!base)
2009                return -1;
2010
2011        /* Cannot stat if what we used to build on no longer exists */
2012        if (read_ref(base, sha1))
2013                return -1;
2014        theirs = lookup_commit_reference(sha1);
2015        if (!theirs)
2016                return -1;
2017
2018        if (read_ref(branch->refname, sha1))
2019                return -1;
2020        ours = lookup_commit_reference(sha1);
2021        if (!ours)
2022                return -1;
2023
2024        /* are we the same? */
2025        if (theirs == ours) {
2026                *num_theirs = *num_ours = 0;
2027                return 0;
2028        }
2029
2030        /* Run "rev-list --left-right ours...theirs" internally... */
2031        argv_array_push(&argv, ""); /* ignored */
2032        argv_array_push(&argv, "--left-right");
2033        argv_array_pushf(&argv, "%s...%s",
2034                         sha1_to_hex(ours->object.sha1),
2035                         sha1_to_hex(theirs->object.sha1));
2036        argv_array_push(&argv, "--");
2037
2038        init_revisions(&revs, NULL);
2039        setup_revisions(argv.argc, argv.argv, &revs, NULL);
2040        if (prepare_revision_walk(&revs))
2041                die("revision walk setup failed");
2042
2043        /* ... and count the commits on each side. */
2044        *num_ours = 0;
2045        *num_theirs = 0;
2046        while (1) {
2047                struct commit *c = get_revision(&revs);
2048                if (!c)
2049                        break;
2050                if (c->object.flags & SYMMETRIC_LEFT)
2051                        (*num_ours)++;
2052                else
2053                        (*num_theirs)++;
2054        }
2055
2056        /* clear object flags smudged by the above traversal */
2057        clear_commit_marks(ours, ALL_REV_FLAGS);
2058        clear_commit_marks(theirs, ALL_REV_FLAGS);
2059
2060        argv_array_clear(&argv);
2061        return 0;
2062}
2063
2064/*
2065 * Return true when there is anything to report, otherwise false.
2066 */
2067int format_tracking_info(struct branch *branch, struct strbuf *sb)
2068{
2069        int ours, theirs;
2070        const char *full_base;
2071        char *base;
2072        int upstream_is_gone = 0;
2073
2074        if (stat_tracking_info(branch, &ours, &theirs, &full_base) < 0) {
2075                if (!full_base)
2076                        return 0;
2077                upstream_is_gone = 1;
2078        }
2079
2080        base = shorten_unambiguous_ref(full_base, 0);
2081        if (upstream_is_gone) {
2082                strbuf_addf(sb,
2083                        _("Your branch is based on '%s', but the upstream is gone.\n"),
2084                        base);
2085                if (advice_status_hints)
2086                        strbuf_addf(sb,
2087                                _("  (use \"git branch --unset-upstream\" to fixup)\n"));
2088        } else if (!ours && !theirs) {
2089                strbuf_addf(sb,
2090                        _("Your branch is up-to-date with '%s'.\n"),
2091                        base);
2092        } else if (!theirs) {
2093                strbuf_addf(sb,
2094                        Q_("Your branch is ahead of '%s' by %d commit.\n",
2095                           "Your branch is ahead of '%s' by %d commits.\n",
2096                           ours),
2097                        base, ours);
2098                if (advice_status_hints)
2099                        strbuf_addf(sb,
2100                                _("  (use \"git push\" to publish your local commits)\n"));
2101        } else if (!ours) {
2102                strbuf_addf(sb,
2103                        Q_("Your branch is behind '%s' by %d commit, "
2104                               "and can be fast-forwarded.\n",
2105                           "Your branch is behind '%s' by %d commits, "
2106                               "and can be fast-forwarded.\n",
2107                           theirs),
2108                        base, theirs);
2109                if (advice_status_hints)
2110                        strbuf_addf(sb,
2111                                _("  (use \"git pull\" to update your local branch)\n"));
2112        } else {
2113                strbuf_addf(sb,
2114                        Q_("Your branch and '%s' have diverged,\n"
2115                               "and have %d and %d different commit each, "
2116                               "respectively.\n",
2117                           "Your branch and '%s' have diverged,\n"
2118                               "and have %d and %d different commits each, "
2119                               "respectively.\n",
2120                           theirs),
2121                        base, ours, theirs);
2122                if (advice_status_hints)
2123                        strbuf_addf(sb,
2124                                _("  (use \"git pull\" to merge the remote branch into yours)\n"));
2125        }
2126        free(base);
2127        return 1;
2128}
2129
2130static int one_local_ref(const char *refname, const struct object_id *oid,
2131                         int flag, void *cb_data)
2132{
2133        struct ref ***local_tail = cb_data;
2134        struct ref *ref;
2135        int len;
2136
2137        /* we already know it starts with refs/ to get here */
2138        if (check_refname_format(refname + 5, 0))
2139                return 0;
2140
2141        len = strlen(refname) + 1;
2142        ref = xcalloc(1, sizeof(*ref) + len);
2143        hashcpy(ref->new_sha1, oid->hash);
2144        memcpy(ref->name, refname, len);
2145        **local_tail = ref;
2146        *local_tail = &ref->next;
2147        return 0;
2148}
2149
2150struct ref *get_local_heads(void)
2151{
2152        struct ref *local_refs = NULL, **local_tail = &local_refs;
2153
2154        for_each_ref(one_local_ref, &local_tail);
2155        return local_refs;
2156}
2157
2158struct ref *guess_remote_head(const struct ref *head,
2159                              const struct ref *refs,
2160                              int all)
2161{
2162        const struct ref *r;
2163        struct ref *list = NULL;
2164        struct ref **tail = &list;
2165
2166        if (!head)
2167                return NULL;
2168
2169        /*
2170         * Some transports support directly peeking at
2171         * where HEAD points; if that is the case, then
2172         * we don't have to guess.
2173         */
2174        if (head->symref)
2175                return copy_ref(find_ref_by_name(refs, head->symref));
2176
2177        /* If refs/heads/master could be right, it is. */
2178        if (!all) {
2179                r = find_ref_by_name(refs, "refs/heads/master");
2180                if (r && !hashcmp(r->old_sha1, head->old_sha1))
2181                        return copy_ref(r);
2182        }
2183
2184        /* Look for another ref that points there */
2185        for (r = refs; r; r = r->next) {
2186                if (r != head &&
2187                    starts_with(r->name, "refs/heads/") &&
2188                    !hashcmp(r->old_sha1, head->old_sha1)) {
2189                        *tail = copy_ref(r);
2190                        tail = &((*tail)->next);
2191                        if (!all)
2192                                break;
2193                }
2194        }
2195
2196        return list;
2197}
2198
2199struct stale_heads_info {
2200        struct string_list *ref_names;
2201        struct ref **stale_refs_tail;
2202        struct refspec *refs;
2203        int ref_count;
2204};
2205
2206static int get_stale_heads_cb(const char *refname, const struct object_id *oid,
2207                              int flags, void *cb_data)
2208{
2209        struct stale_heads_info *info = cb_data;
2210        struct string_list matches = STRING_LIST_INIT_DUP;
2211        struct refspec query;
2212        int i, stale = 1;
2213        memset(&query, 0, sizeof(struct refspec));
2214        query.dst = (char *)refname;
2215
2216        query_refspecs_multiple(info->refs, info->ref_count, &query, &matches);
2217        if (matches.nr == 0)
2218                goto clean_exit; /* No matches */
2219
2220        /*
2221         * If we did find a suitable refspec and it's not a symref and
2222         * it's not in the list of refs that currently exist in that
2223         * remote, we consider it to be stale. In order to deal with
2224         * overlapping refspecs, we need to go over all of the
2225         * matching refs.
2226         */
2227        if (flags & REF_ISSYMREF)
2228                goto clean_exit;
2229
2230        for (i = 0; stale && i < matches.nr; i++)
2231                if (string_list_has_string(info->ref_names, matches.items[i].string))
2232                        stale = 0;
2233
2234        if (stale) {
2235                struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
2236                hashcpy(ref->new_sha1, oid->hash);
2237        }
2238
2239clean_exit:
2240        string_list_clear(&matches, 0);
2241        return 0;
2242}
2243
2244struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fetch_map)
2245{
2246        struct ref *ref, *stale_refs = NULL;
2247        struct string_list ref_names = STRING_LIST_INIT_NODUP;
2248        struct stale_heads_info info;
2249
2250        info.ref_names = &ref_names;
2251        info.stale_refs_tail = &stale_refs;
2252        info.refs = refs;
2253        info.ref_count = ref_count;
2254        for (ref = fetch_map; ref; ref = ref->next)
2255                string_list_append(&ref_names, ref->name);
2256        string_list_sort(&ref_names);
2257        for_each_ref(get_stale_heads_cb, &info);
2258        string_list_clear(&ref_names, 0);
2259        return stale_refs;
2260}
2261
2262/*
2263 * Compare-and-swap
2264 */
2265static void clear_cas_option(struct push_cas_option *cas)
2266{
2267        int i;
2268
2269        for (i = 0; i < cas->nr; i++)
2270                free(cas->entry[i].refname);
2271        free(cas->entry);
2272        memset(cas, 0, sizeof(*cas));
2273}
2274
2275static struct push_cas *add_cas_entry(struct push_cas_option *cas,
2276                                      const char *refname,
2277                                      size_t refnamelen)
2278{
2279        struct push_cas *entry;
2280        ALLOC_GROW(cas->entry, cas->nr + 1, cas->alloc);
2281        entry = &cas->entry[cas->nr++];
2282        memset(entry, 0, sizeof(*entry));
2283        entry->refname = xmemdupz(refname, refnamelen);
2284        return entry;
2285}
2286
2287int parse_push_cas_option(struct push_cas_option *cas, const char *arg, int unset)
2288{
2289        const char *colon;
2290        struct push_cas *entry;
2291
2292        if (unset) {
2293                /* "--no-<option>" */
2294                clear_cas_option(cas);
2295                return 0;
2296        }
2297
2298        if (!arg) {
2299                /* just "--<option>" */
2300                cas->use_tracking_for_rest = 1;
2301                return 0;
2302        }
2303
2304        /* "--<option>=refname" or "--<option>=refname:value" */
2305        colon = strchrnul(arg, ':');
2306        entry = add_cas_entry(cas, arg, colon - arg);
2307        if (!*colon)
2308                entry->use_tracking = 1;
2309        else if (get_sha1(colon + 1, entry->expect))
2310                return error("cannot parse expected object name '%s'", colon + 1);
2311        return 0;
2312}
2313
2314int parseopt_push_cas_option(const struct option *opt, const char *arg, int unset)
2315{
2316        return parse_push_cas_option(opt->value, arg, unset);
2317}
2318
2319int is_empty_cas(const struct push_cas_option *cas)
2320{
2321        return !cas->use_tracking_for_rest && !cas->nr;
2322}
2323
2324/*
2325 * Look at remote.fetch refspec and see if we have a remote
2326 * tracking branch for the refname there.  Fill its current
2327 * value in sha1[].
2328 * If we cannot do so, return negative to signal an error.
2329 */
2330static int remote_tracking(struct remote *remote, const char *refname,
2331                           unsigned char sha1[20])
2332{
2333        char *dst;
2334
2335        dst = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
2336        if (!dst)
2337                return -1; /* no tracking ref for refname at remote */
2338        if (read_ref(dst, sha1))
2339                return -1; /* we know what the tracking ref is but we cannot read it */
2340        return 0;
2341}
2342
2343static void apply_cas(struct push_cas_option *cas,
2344                      struct remote *remote,
2345                      struct ref *ref)
2346{
2347        int i;
2348
2349        /* Find an explicit --<option>=<name>[:<value>] entry */
2350        for (i = 0; i < cas->nr; i++) {
2351                struct push_cas *entry = &cas->entry[i];
2352                if (!refname_match(entry->refname, ref->name))
2353                        continue;
2354                ref->expect_old_sha1 = 1;
2355                if (!entry->use_tracking)
2356                        hashcpy(ref->old_sha1_expect, cas->entry[i].expect);
2357                else if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2358                        ref->expect_old_no_trackback = 1;
2359                return;
2360        }
2361
2362        /* Are we using "--<option>" to cover all? */
2363        if (!cas->use_tracking_for_rest)
2364                return;
2365
2366        ref->expect_old_sha1 = 1;
2367        if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2368                ref->expect_old_no_trackback = 1;
2369}
2370
2371void apply_push_cas(struct push_cas_option *cas,
2372                    struct remote *remote,
2373                    struct ref *remote_refs)
2374{
2375        struct ref *ref;
2376        for (ref = remote_refs; ref; ref = ref->next)
2377                apply_cas(cas, remote, ref);
2378}