remote.con commit Merge branch 'maint-2.0' into maint (3c2dc76)
   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
  12enum map_direction { FROM_SRC, FROM_DST };
  13
  14static struct refspec s_tag_refspec = {
  15        0,
  16        1,
  17        0,
  18        0,
  19        "refs/tags/*",
  20        "refs/tags/*"
  21};
  22
  23const struct refspec *tag_refspec = &s_tag_refspec;
  24
  25struct counted_string {
  26        size_t len;
  27        const char *s;
  28};
  29struct rewrite {
  30        const char *base;
  31        size_t baselen;
  32        struct counted_string *instead_of;
  33        int instead_of_nr;
  34        int instead_of_alloc;
  35};
  36struct rewrites {
  37        struct rewrite **rewrite;
  38        int rewrite_alloc;
  39        int rewrite_nr;
  40};
  41
  42static struct remote **remotes;
  43static int remotes_alloc;
  44static int remotes_nr;
  45
  46static struct branch **branches;
  47static int branches_alloc;
  48static int branches_nr;
  49
  50static struct branch *current_branch;
  51static const char *default_remote_name;
  52static const char *branch_pushremote_name;
  53static const char *pushremote_name;
  54static int explicit_default_remote_name;
  55
  56static struct rewrites rewrites;
  57static struct rewrites rewrites_push;
  58
  59#define BUF_SIZE (2048)
  60static char buffer[BUF_SIZE];
  61
  62static int valid_remote(const struct remote *remote)
  63{
  64        return (!!remote->url) || (!!remote->foreign_vcs);
  65}
  66
  67static const char *alias_url(const char *url, struct rewrites *r)
  68{
  69        int i, j;
  70        char *ret;
  71        struct counted_string *longest;
  72        int longest_i;
  73
  74        longest = NULL;
  75        longest_i = -1;
  76        for (i = 0; i < r->rewrite_nr; i++) {
  77                if (!r->rewrite[i])
  78                        continue;
  79                for (j = 0; j < r->rewrite[i]->instead_of_nr; j++) {
  80                        if (starts_with(url, r->rewrite[i]->instead_of[j].s) &&
  81                            (!longest ||
  82                             longest->len < r->rewrite[i]->instead_of[j].len)) {
  83                                longest = &(r->rewrite[i]->instead_of[j]);
  84                                longest_i = i;
  85                        }
  86                }
  87        }
  88        if (!longest)
  89                return url;
  90
  91        ret = xmalloc(r->rewrite[longest_i]->baselen +
  92                     (strlen(url) - longest->len) + 1);
  93        strcpy(ret, r->rewrite[longest_i]->base);
  94        strcpy(ret + r->rewrite[longest_i]->baselen, url + longest->len);
  95        return ret;
  96}
  97
  98static void add_push_refspec(struct remote *remote, const char *ref)
  99{
 100        ALLOC_GROW(remote->push_refspec,
 101                   remote->push_refspec_nr + 1,
 102                   remote->push_refspec_alloc);
 103        remote->push_refspec[remote->push_refspec_nr++] = ref;
 104}
 105
 106static void add_fetch_refspec(struct remote *remote, const char *ref)
 107{
 108        ALLOC_GROW(remote->fetch_refspec,
 109                   remote->fetch_refspec_nr + 1,
 110                   remote->fetch_refspec_alloc);
 111        remote->fetch_refspec[remote->fetch_refspec_nr++] = ref;
 112}
 113
 114static void add_url(struct remote *remote, const char *url)
 115{
 116        ALLOC_GROW(remote->url, remote->url_nr + 1, remote->url_alloc);
 117        remote->url[remote->url_nr++] = url;
 118}
 119
 120static void add_pushurl(struct remote *remote, const char *pushurl)
 121{
 122        ALLOC_GROW(remote->pushurl, remote->pushurl_nr + 1, remote->pushurl_alloc);
 123        remote->pushurl[remote->pushurl_nr++] = pushurl;
 124}
 125
 126static void add_pushurl_alias(struct remote *remote, const char *url)
 127{
 128        const char *pushurl = alias_url(url, &rewrites_push);
 129        if (pushurl != url)
 130                add_pushurl(remote, pushurl);
 131}
 132
 133static void add_url_alias(struct remote *remote, const char *url)
 134{
 135        add_url(remote, alias_url(url, &rewrites));
 136        add_pushurl_alias(remote, url);
 137}
 138
 139static struct remote *make_remote(const char *name, int len)
 140{
 141        struct remote *ret;
 142        int i;
 143
 144        for (i = 0; i < remotes_nr; i++) {
 145                if (len ? (!strncmp(name, remotes[i]->name, len) &&
 146                           !remotes[i]->name[len]) :
 147                    !strcmp(name, remotes[i]->name))
 148                        return remotes[i];
 149        }
 150
 151        ret = xcalloc(1, sizeof(struct remote));
 152        ret->prune = -1;  /* unspecified */
 153        ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 154        remotes[remotes_nr++] = ret;
 155        if (len)
 156                ret->name = xstrndup(name, len);
 157        else
 158                ret->name = xstrdup(name);
 159        return ret;
 160}
 161
 162static void add_merge(struct branch *branch, const char *name)
 163{
 164        ALLOC_GROW(branch->merge_name, branch->merge_nr + 1,
 165                   branch->merge_alloc);
 166        branch->merge_name[branch->merge_nr++] = name;
 167}
 168
 169static struct branch *make_branch(const char *name, int len)
 170{
 171        struct branch *ret;
 172        int i;
 173
 174        for (i = 0; i < branches_nr; i++) {
 175                if (len ? (!strncmp(name, branches[i]->name, len) &&
 176                           !branches[i]->name[len]) :
 177                    !strcmp(name, branches[i]->name))
 178                        return branches[i];
 179        }
 180
 181        ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 182        ret = xcalloc(1, sizeof(struct branch));
 183        branches[branches_nr++] = ret;
 184        if (len)
 185                ret->name = xstrndup(name, len);
 186        else
 187                ret->name = xstrdup(name);
 188        ret->refname = xstrfmt("refs/heads/%s", ret->name);
 189
 190        return ret;
 191}
 192
 193static struct rewrite *make_rewrite(struct rewrites *r, const char *base, int len)
 194{
 195        struct rewrite *ret;
 196        int i;
 197
 198        for (i = 0; i < r->rewrite_nr; i++) {
 199                if (len
 200                    ? (len == r->rewrite[i]->baselen &&
 201                       !strncmp(base, r->rewrite[i]->base, len))
 202                    : !strcmp(base, r->rewrite[i]->base))
 203                        return r->rewrite[i];
 204        }
 205
 206        ALLOC_GROW(r->rewrite, r->rewrite_nr + 1, r->rewrite_alloc);
 207        ret = xcalloc(1, sizeof(struct rewrite));
 208        r->rewrite[r->rewrite_nr++] = ret;
 209        if (len) {
 210                ret->base = xstrndup(base, len);
 211                ret->baselen = len;
 212        }
 213        else {
 214                ret->base = xstrdup(base);
 215                ret->baselen = strlen(base);
 216        }
 217        return ret;
 218}
 219
 220static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 221{
 222        ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 223        rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 224        rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 225        rewrite->instead_of_nr++;
 226}
 227
 228static void read_remotes_file(struct remote *remote)
 229{
 230        FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
 231
 232        if (!f)
 233                return;
 234        remote->origin = REMOTE_REMOTES;
 235        while (fgets(buffer, BUF_SIZE, f)) {
 236                int value_list;
 237                char *s, *p;
 238
 239                if (starts_with(buffer, "URL:")) {
 240                        value_list = 0;
 241                        s = buffer + 4;
 242                } else if (starts_with(buffer, "Push:")) {
 243                        value_list = 1;
 244                        s = buffer + 5;
 245                } else if (starts_with(buffer, "Pull:")) {
 246                        value_list = 2;
 247                        s = buffer + 5;
 248                } else
 249                        continue;
 250
 251                while (isspace(*s))
 252                        s++;
 253                if (!*s)
 254                        continue;
 255
 256                p = s + strlen(s);
 257                while (isspace(p[-1]))
 258                        *--p = 0;
 259
 260                switch (value_list) {
 261                case 0:
 262                        add_url_alias(remote, xstrdup(s));
 263                        break;
 264                case 1:
 265                        add_push_refspec(remote, xstrdup(s));
 266                        break;
 267                case 2:
 268                        add_fetch_refspec(remote, xstrdup(s));
 269                        break;
 270                }
 271        }
 272        fclose(f);
 273}
 274
 275static void read_branches_file(struct remote *remote)
 276{
 277        char *frag;
 278        struct strbuf branch = STRBUF_INIT;
 279        int n = 1000;
 280        FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 281        char *s, *p;
 282        int len;
 283
 284        if (!f)
 285                return;
 286        s = fgets(buffer, BUF_SIZE, f);
 287        fclose(f);
 288        if (!s)
 289                return;
 290        while (isspace(*s))
 291                s++;
 292        if (!*s)
 293                return;
 294        remote->origin = REMOTE_BRANCHES;
 295        p = s + strlen(s);
 296        while (isspace(p[-1]))
 297                *--p = 0;
 298        len = p - s;
 299        p = xmalloc(len + 1);
 300        strcpy(p, s);
 301
 302        /*
 303         * The branches file would have URL and optionally
 304         * #branch specified.  The "master" (or specified) branch is
 305         * fetched and stored in the local branch of the same name.
 306         */
 307        frag = strchr(p, '#');
 308        if (frag) {
 309                *(frag++) = '\0';
 310                strbuf_addf(&branch, "refs/heads/%s", frag);
 311        } else
 312                strbuf_addstr(&branch, "refs/heads/master");
 313
 314        strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 315        add_url_alias(remote, p);
 316        add_fetch_refspec(remote, strbuf_detach(&branch, NULL));
 317        /*
 318         * Cogito compatible push: push current HEAD to remote #branch
 319         * (master if missing)
 320         */
 321        strbuf_init(&branch, 0);
 322        strbuf_addstr(&branch, "HEAD");
 323        if (frag)
 324                strbuf_addf(&branch, ":refs/heads/%s", frag);
 325        else
 326                strbuf_addstr(&branch, ":refs/heads/master");
 327        add_push_refspec(remote, strbuf_detach(&branch, NULL));
 328        remote->fetch_tags = 1; /* always auto-follow */
 329}
 330
 331static int handle_config(const char *key, const char *value, void *cb)
 332{
 333        const char *name;
 334        const char *subkey;
 335        struct remote *remote;
 336        struct branch *branch;
 337        if (starts_with(key, "branch.")) {
 338                name = key + 7;
 339                subkey = strrchr(name, '.');
 340                if (!subkey)
 341                        return 0;
 342                branch = make_branch(name, subkey - name);
 343                if (!strcmp(subkey, ".remote")) {
 344                        if (git_config_string(&branch->remote_name, key, value))
 345                                return -1;
 346                        if (branch == current_branch) {
 347                                default_remote_name = branch->remote_name;
 348                                explicit_default_remote_name = 1;
 349                        }
 350                } else if (!strcmp(subkey, ".pushremote")) {
 351                        if (branch == current_branch)
 352                                if (git_config_string(&branch_pushremote_name, key, value))
 353                                        return -1;
 354                } else if (!strcmp(subkey, ".merge")) {
 355                        if (!value)
 356                                return config_error_nonbool(key);
 357                        add_merge(branch, xstrdup(value));
 358                }
 359                return 0;
 360        }
 361        if (starts_with(key, "url.")) {
 362                struct rewrite *rewrite;
 363                name = key + 4;
 364                subkey = strrchr(name, '.');
 365                if (!subkey)
 366                        return 0;
 367                if (!strcmp(subkey, ".insteadof")) {
 368                        rewrite = make_rewrite(&rewrites, name, subkey - name);
 369                        if (!value)
 370                                return config_error_nonbool(key);
 371                        add_instead_of(rewrite, xstrdup(value));
 372                } else if (!strcmp(subkey, ".pushinsteadof")) {
 373                        rewrite = make_rewrite(&rewrites_push, name, subkey - name);
 374                        if (!value)
 375                                return config_error_nonbool(key);
 376                        add_instead_of(rewrite, xstrdup(value));
 377                }
 378        }
 379
 380        if (!starts_with(key,  "remote."))
 381                return 0;
 382        name = key + 7;
 383
 384        /* Handle remote.* variables */
 385        if (!strcmp(name, "pushdefault"))
 386                return git_config_string(&pushremote_name, key, value);
 387
 388        /* Handle remote.<name>.* variables */
 389        if (*name == '/') {
 390                warning("Config remote shorthand cannot begin with '/': %s",
 391                        name);
 392                return 0;
 393        }
 394        subkey = strrchr(name, '.');
 395        if (!subkey)
 396                return 0;
 397        remote = make_remote(name, subkey - name);
 398        remote->origin = REMOTE_CONFIG;
 399        if (!strcmp(subkey, ".mirror"))
 400                remote->mirror = git_config_bool(key, value);
 401        else if (!strcmp(subkey, ".skipdefaultupdate"))
 402                remote->skip_default_update = git_config_bool(key, value);
 403        else if (!strcmp(subkey, ".skipfetchall"))
 404                remote->skip_default_update = git_config_bool(key, value);
 405        else if (!strcmp(subkey, ".prune"))
 406                remote->prune = git_config_bool(key, value);
 407        else if (!strcmp(subkey, ".url")) {
 408                const char *v;
 409                if (git_config_string(&v, key, value))
 410                        return -1;
 411                add_url(remote, v);
 412        } else if (!strcmp(subkey, ".pushurl")) {
 413                const char *v;
 414                if (git_config_string(&v, key, value))
 415                        return -1;
 416                add_pushurl(remote, v);
 417        } else if (!strcmp(subkey, ".push")) {
 418                const char *v;
 419                if (git_config_string(&v, key, value))
 420                        return -1;
 421                add_push_refspec(remote, v);
 422        } else if (!strcmp(subkey, ".fetch")) {
 423                const char *v;
 424                if (git_config_string(&v, key, value))
 425                        return -1;
 426                add_fetch_refspec(remote, v);
 427        } else if (!strcmp(subkey, ".receivepack")) {
 428                const char *v;
 429                if (git_config_string(&v, key, value))
 430                        return -1;
 431                if (!remote->receivepack)
 432                        remote->receivepack = v;
 433                else
 434                        error("more than one receivepack given, using the first");
 435        } else if (!strcmp(subkey, ".uploadpack")) {
 436                const char *v;
 437                if (git_config_string(&v, key, value))
 438                        return -1;
 439                if (!remote->uploadpack)
 440                        remote->uploadpack = v;
 441                else
 442                        error("more than one uploadpack given, using the first");
 443        } else if (!strcmp(subkey, ".tagopt")) {
 444                if (!strcmp(value, "--no-tags"))
 445                        remote->fetch_tags = -1;
 446                else if (!strcmp(value, "--tags"))
 447                        remote->fetch_tags = 2;
 448        } else if (!strcmp(subkey, ".proxy")) {
 449                return git_config_string((const char **)&remote->http_proxy,
 450                                         key, value);
 451        } else if (!strcmp(subkey, ".vcs")) {
 452                return git_config_string(&remote->foreign_vcs, key, value);
 453        }
 454        return 0;
 455}
 456
 457static void alias_all_urls(void)
 458{
 459        int i, j;
 460        for (i = 0; i < remotes_nr; i++) {
 461                int add_pushurl_aliases;
 462                if (!remotes[i])
 463                        continue;
 464                for (j = 0; j < remotes[i]->pushurl_nr; j++) {
 465                        remotes[i]->pushurl[j] = alias_url(remotes[i]->pushurl[j], &rewrites);
 466                }
 467                add_pushurl_aliases = remotes[i]->pushurl_nr == 0;
 468                for (j = 0; j < remotes[i]->url_nr; j++) {
 469                        if (add_pushurl_aliases)
 470                                add_pushurl_alias(remotes[i], remotes[i]->url[j]);
 471                        remotes[i]->url[j] = alias_url(remotes[i]->url[j], &rewrites);
 472                }
 473        }
 474}
 475
 476static void read_config(void)
 477{
 478        unsigned char sha1[20];
 479        const char *head_ref;
 480        int flag;
 481        if (default_remote_name) /* did this already */
 482                return;
 483        default_remote_name = "origin";
 484        current_branch = NULL;
 485        head_ref = resolve_ref_unsafe("HEAD", sha1, 0, &flag);
 486        if (head_ref && (flag & REF_ISSYMREF) &&
 487            skip_prefix(head_ref, "refs/heads/", &head_ref)) {
 488                current_branch = make_branch(head_ref, 0);
 489        }
 490        git_config(handle_config, NULL);
 491        if (branch_pushremote_name) {
 492                free((char *)pushremote_name);
 493                pushremote_name = branch_pushremote_name;
 494        }
 495        alias_all_urls();
 496}
 497
 498/*
 499 * This function frees a refspec array.
 500 * Warning: code paths should be checked to ensure that the src
 501 *          and dst pointers are always freeable pointers as well
 502 *          as the refspec pointer itself.
 503 */
 504static void free_refspecs(struct refspec *refspec, int nr_refspec)
 505{
 506        int i;
 507
 508        if (!refspec)
 509                return;
 510
 511        for (i = 0; i < nr_refspec; i++) {
 512                free(refspec[i].src);
 513                free(refspec[i].dst);
 514        }
 515        free(refspec);
 516}
 517
 518static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 519{
 520        int i;
 521        struct refspec *rs = xcalloc(nr_refspec, sizeof(*rs));
 522
 523        for (i = 0; i < nr_refspec; i++) {
 524                size_t llen;
 525                int is_glob;
 526                const char *lhs, *rhs;
 527                int flags;
 528
 529                is_glob = 0;
 530
 531                lhs = refspec[i];
 532                if (*lhs == '+') {
 533                        rs[i].force = 1;
 534                        lhs++;
 535                }
 536
 537                rhs = strrchr(lhs, ':');
 538
 539                /*
 540                 * Before going on, special case ":" (or "+:") as a refspec
 541                 * for pushing matching refs.
 542                 */
 543                if (!fetch && rhs == lhs && rhs[1] == '\0') {
 544                        rs[i].matching = 1;
 545                        continue;
 546                }
 547
 548                if (rhs) {
 549                        size_t rlen = strlen(++rhs);
 550                        is_glob = (1 <= rlen && strchr(rhs, '*'));
 551                        rs[i].dst = xstrndup(rhs, rlen);
 552                }
 553
 554                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 555                if (1 <= llen && memchr(lhs, '*', llen)) {
 556                        if ((rhs && !is_glob) || (!rhs && fetch))
 557                                goto invalid;
 558                        is_glob = 1;
 559                } else if (rhs && is_glob) {
 560                        goto invalid;
 561                }
 562
 563                rs[i].pattern = is_glob;
 564                rs[i].src = xstrndup(lhs, llen);
 565                flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 566
 567                if (fetch) {
 568                        unsigned char unused[40];
 569
 570                        /* LHS */
 571                        if (!*rs[i].src)
 572                                ; /* empty is ok; it means "HEAD" */
 573                        else if (llen == 40 && !get_sha1_hex(rs[i].src, unused))
 574                                rs[i].exact_sha1 = 1; /* ok */
 575                        else if (!check_refname_format(rs[i].src, flags))
 576                                ; /* valid looking ref is ok */
 577                        else
 578                                goto invalid;
 579                        /* RHS */
 580                        if (!rs[i].dst)
 581                                ; /* missing is ok; it is the same as empty */
 582                        else if (!*rs[i].dst)
 583                                ; /* empty is ok; it means "do not store" */
 584                        else if (!check_refname_format(rs[i].dst, flags))
 585                                ; /* valid looking ref is ok */
 586                        else
 587                                goto invalid;
 588                } else {
 589                        /*
 590                         * LHS
 591                         * - empty is allowed; it means delete.
 592                         * - when wildcarded, it must be a valid looking ref.
 593                         * - otherwise, it must be an extended SHA-1, but
 594                         *   there is no existing way to validate this.
 595                         */
 596                        if (!*rs[i].src)
 597                                ; /* empty is ok */
 598                        else if (is_glob) {
 599                                if (check_refname_format(rs[i].src, flags))
 600                                        goto invalid;
 601                        }
 602                        else
 603                                ; /* anything goes, for now */
 604                        /*
 605                         * RHS
 606                         * - missing is allowed, but LHS then must be a
 607                         *   valid looking ref.
 608                         * - empty is not allowed.
 609                         * - otherwise it must be a valid looking ref.
 610                         */
 611                        if (!rs[i].dst) {
 612                                if (check_refname_format(rs[i].src, flags))
 613                                        goto invalid;
 614                        } else if (!*rs[i].dst) {
 615                                goto invalid;
 616                        } else {
 617                                if (check_refname_format(rs[i].dst, flags))
 618                                        goto invalid;
 619                        }
 620                }
 621        }
 622        return rs;
 623
 624 invalid:
 625        if (verify) {
 626                /*
 627                 * nr_refspec must be greater than zero and i must be valid
 628                 * since it is only possible to reach this point from within
 629                 * the for loop above.
 630                 */
 631                free_refspecs(rs, i+1);
 632                return NULL;
 633        }
 634        die("Invalid refspec '%s'", refspec[i]);
 635}
 636
 637int valid_fetch_refspec(const char *fetch_refspec_str)
 638{
 639        struct refspec *refspec;
 640
 641        refspec = parse_refspec_internal(1, &fetch_refspec_str, 1, 1);
 642        free_refspecs(refspec, 1);
 643        return !!refspec;
 644}
 645
 646struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 647{
 648        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 649}
 650
 651static struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 652{
 653        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 654}
 655
 656void free_refspec(int nr_refspec, struct refspec *refspec)
 657{
 658        int i;
 659        for (i = 0; i < nr_refspec; i++) {
 660                free(refspec[i].src);
 661                free(refspec[i].dst);
 662        }
 663        free(refspec);
 664}
 665
 666static int valid_remote_nick(const char *name)
 667{
 668        if (!name[0] || is_dot_or_dotdot(name))
 669                return 0;
 670        return !strchr(name, '/'); /* no slash */
 671}
 672
 673static struct remote *remote_get_1(const char *name, const char *pushremote_name)
 674{
 675        struct remote *ret;
 676        int name_given = 0;
 677
 678        if (name)
 679                name_given = 1;
 680        else {
 681                if (pushremote_name) {
 682                        name = pushremote_name;
 683                        name_given = 1;
 684                } else {
 685                        name = default_remote_name;
 686                        name_given = explicit_default_remote_name;
 687                }
 688        }
 689
 690        ret = make_remote(name, 0);
 691        if (valid_remote_nick(name)) {
 692                if (!valid_remote(ret))
 693                        read_remotes_file(ret);
 694                if (!valid_remote(ret))
 695                        read_branches_file(ret);
 696        }
 697        if (name_given && !valid_remote(ret))
 698                add_url_alias(ret, name);
 699        if (!valid_remote(ret))
 700                return NULL;
 701        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 702        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 703        return ret;
 704}
 705
 706struct remote *remote_get(const char *name)
 707{
 708        read_config();
 709        return remote_get_1(name, NULL);
 710}
 711
 712struct remote *pushremote_get(const char *name)
 713{
 714        read_config();
 715        return remote_get_1(name, pushremote_name);
 716}
 717
 718int remote_is_configured(const char *name)
 719{
 720        int i;
 721        read_config();
 722
 723        for (i = 0; i < remotes_nr; i++)
 724                if (!strcmp(name, remotes[i]->name))
 725                        return 1;
 726        return 0;
 727}
 728
 729int for_each_remote(each_remote_fn fn, void *priv)
 730{
 731        int i, result = 0;
 732        read_config();
 733        for (i = 0; i < remotes_nr && !result; i++) {
 734                struct remote *r = remotes[i];
 735                if (!r)
 736                        continue;
 737                if (!r->fetch)
 738                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 739                                                       r->fetch_refspec);
 740                if (!r->push)
 741                        r->push = parse_push_refspec(r->push_refspec_nr,
 742                                                     r->push_refspec);
 743                result = fn(r, priv);
 744        }
 745        return result;
 746}
 747
 748static void handle_duplicate(struct ref *ref1, struct ref *ref2)
 749{
 750        if (strcmp(ref1->name, ref2->name)) {
 751                if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 752                    ref2->fetch_head_status != FETCH_HEAD_IGNORE) {
 753                        die(_("Cannot fetch both %s and %s to %s"),
 754                            ref1->name, ref2->name, ref2->peer_ref->name);
 755                } else if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 756                           ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 757                        warning(_("%s usually tracks %s, not %s"),
 758                                ref2->peer_ref->name, ref2->name, ref1->name);
 759                } else if (ref1->fetch_head_status == FETCH_HEAD_IGNORE &&
 760                           ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 761                        die(_("%s tracks both %s and %s"),
 762                            ref2->peer_ref->name, ref1->name, ref2->name);
 763                } else {
 764                        /*
 765                         * This last possibility doesn't occur because
 766                         * FETCH_HEAD_IGNORE entries always appear at
 767                         * the end of the list.
 768                         */
 769                        die(_("Internal error"));
 770                }
 771        }
 772        free(ref2->peer_ref);
 773        free(ref2);
 774}
 775
 776struct ref *ref_remove_duplicates(struct ref *ref_map)
 777{
 778        struct string_list refs = STRING_LIST_INIT_NODUP;
 779        struct ref *retval = NULL;
 780        struct ref **p = &retval;
 781
 782        while (ref_map) {
 783                struct ref *ref = ref_map;
 784
 785                ref_map = ref_map->next;
 786                ref->next = NULL;
 787
 788                if (!ref->peer_ref) {
 789                        *p = ref;
 790                        p = &ref->next;
 791                } else {
 792                        struct string_list_item *item =
 793                                string_list_insert(&refs, ref->peer_ref->name);
 794
 795                        if (item->util) {
 796                                /* Entry already existed */
 797                                handle_duplicate((struct ref *)item->util, ref);
 798                        } else {
 799                                *p = ref;
 800                                p = &ref->next;
 801                                item->util = ref;
 802                        }
 803                }
 804        }
 805
 806        string_list_clear(&refs, 0);
 807        return retval;
 808}
 809
 810int remote_has_url(struct remote *remote, const char *url)
 811{
 812        int i;
 813        for (i = 0; i < remote->url_nr; i++) {
 814                if (!strcmp(remote->url[i], url))
 815                        return 1;
 816        }
 817        return 0;
 818}
 819
 820static int match_name_with_pattern(const char *key, const char *name,
 821                                   const char *value, char **result)
 822{
 823        const char *kstar = strchr(key, '*');
 824        size_t klen;
 825        size_t ksuffixlen;
 826        size_t namelen;
 827        int ret;
 828        if (!kstar)
 829                die("Key '%s' of pattern had no '*'", key);
 830        klen = kstar - key;
 831        ksuffixlen = strlen(kstar + 1);
 832        namelen = strlen(name);
 833        ret = !strncmp(name, key, klen) && namelen >= klen + ksuffixlen &&
 834                !memcmp(name + namelen - ksuffixlen, kstar + 1, ksuffixlen);
 835        if (ret && value) {
 836                const char *vstar = strchr(value, '*');
 837                size_t vlen;
 838                size_t vsuffixlen;
 839                if (!vstar)
 840                        die("Value '%s' of pattern has no '*'", value);
 841                vlen = vstar - value;
 842                vsuffixlen = strlen(vstar + 1);
 843                *result = xmalloc(vlen + vsuffixlen +
 844                                  strlen(name) -
 845                                  klen - ksuffixlen + 1);
 846                strncpy(*result, value, vlen);
 847                strncpy(*result + vlen,
 848                        name + klen, namelen - klen - ksuffixlen);
 849                strcpy(*result + vlen + namelen - klen - ksuffixlen,
 850                       vstar + 1);
 851        }
 852        return ret;
 853}
 854
 855static void query_refspecs_multiple(struct refspec *refs, int ref_count, struct refspec *query, struct string_list *results)
 856{
 857        int i;
 858        int find_src = !query->src;
 859
 860        if (find_src && !query->dst)
 861                error("query_refspecs_multiple: need either src or dst");
 862
 863        for (i = 0; i < ref_count; i++) {
 864                struct refspec *refspec = &refs[i];
 865                const char *key = find_src ? refspec->dst : refspec->src;
 866                const char *value = find_src ? refspec->src : refspec->dst;
 867                const char *needle = find_src ? query->dst : query->src;
 868                char **result = find_src ? &query->src : &query->dst;
 869
 870                if (!refspec->dst)
 871                        continue;
 872                if (refspec->pattern) {
 873                        if (match_name_with_pattern(key, needle, value, result))
 874                                string_list_append_nodup(results, *result);
 875                } else if (!strcmp(needle, key)) {
 876                        string_list_append(results, value);
 877                }
 878        }
 879}
 880
 881int query_refspecs(struct refspec *refs, int ref_count, struct refspec *query)
 882{
 883        int i;
 884        int find_src = !query->src;
 885        const char *needle = find_src ? query->dst : query->src;
 886        char **result = find_src ? &query->src : &query->dst;
 887
 888        if (find_src && !query->dst)
 889                return error("query_refspecs: need either src or dst");
 890
 891        for (i = 0; i < ref_count; i++) {
 892                struct refspec *refspec = &refs[i];
 893                const char *key = find_src ? refspec->dst : refspec->src;
 894                const char *value = find_src ? refspec->src : refspec->dst;
 895
 896                if (!refspec->dst)
 897                        continue;
 898                if (refspec->pattern) {
 899                        if (match_name_with_pattern(key, needle, value, result)) {
 900                                query->force = refspec->force;
 901                                return 0;
 902                        }
 903                } else if (!strcmp(needle, key)) {
 904                        *result = xstrdup(value);
 905                        query->force = refspec->force;
 906                        return 0;
 907                }
 908        }
 909        return -1;
 910}
 911
 912char *apply_refspecs(struct refspec *refspecs, int nr_refspec,
 913                     const char *name)
 914{
 915        struct refspec query;
 916
 917        memset(&query, 0, sizeof(struct refspec));
 918        query.src = (char *)name;
 919
 920        if (query_refspecs(refspecs, nr_refspec, &query))
 921                return NULL;
 922
 923        return query.dst;
 924}
 925
 926int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 927{
 928        return query_refspecs(remote->fetch, remote->fetch_refspec_nr, refspec);
 929}
 930
 931static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 932                const char *name)
 933{
 934        size_t len = strlen(name);
 935        struct ref *ref = xcalloc(1, sizeof(struct ref) + prefixlen + len + 1);
 936        memcpy(ref->name, prefix, prefixlen);
 937        memcpy(ref->name + prefixlen, name, len);
 938        return ref;
 939}
 940
 941struct ref *alloc_ref(const char *name)
 942{
 943        return alloc_ref_with_prefix("", 0, name);
 944}
 945
 946struct ref *copy_ref(const struct ref *ref)
 947{
 948        struct ref *cpy;
 949        size_t len;
 950        if (!ref)
 951                return NULL;
 952        len = strlen(ref->name);
 953        cpy = xmalloc(sizeof(struct ref) + len + 1);
 954        memcpy(cpy, ref, sizeof(struct ref) + len + 1);
 955        cpy->next = NULL;
 956        cpy->symref = ref->symref ? xstrdup(ref->symref) : NULL;
 957        cpy->remote_status = ref->remote_status ? xstrdup(ref->remote_status) : NULL;
 958        cpy->peer_ref = copy_ref(ref->peer_ref);
 959        return cpy;
 960}
 961
 962struct ref *copy_ref_list(const struct ref *ref)
 963{
 964        struct ref *ret = NULL;
 965        struct ref **tail = &ret;
 966        while (ref) {
 967                *tail = copy_ref(ref);
 968                ref = ref->next;
 969                tail = &((*tail)->next);
 970        }
 971        return ret;
 972}
 973
 974static void free_ref(struct ref *ref)
 975{
 976        if (!ref)
 977                return;
 978        free_ref(ref->peer_ref);
 979        free(ref->remote_status);
 980        free(ref->symref);
 981        free(ref);
 982}
 983
 984void free_refs(struct ref *ref)
 985{
 986        struct ref *next;
 987        while (ref) {
 988                next = ref->next;
 989                free_ref(ref);
 990                ref = next;
 991        }
 992}
 993
 994int ref_compare_name(const void *va, const void *vb)
 995{
 996        const struct ref *a = va, *b = vb;
 997        return strcmp(a->name, b->name);
 998}
 999
1000static void *ref_list_get_next(const void *a)
1001{
1002        return ((const struct ref *)a)->next;
1003}
1004
1005static void ref_list_set_next(void *a, void *next)
1006{
1007        ((struct ref *)a)->next = next;
1008}
1009
1010void sort_ref_list(struct ref **l, int (*cmp)(const void *, const void *))
1011{
1012        *l = llist_mergesort(*l, ref_list_get_next, ref_list_set_next, cmp);
1013}
1014
1015int count_refspec_match(const char *pattern,
1016                        struct ref *refs,
1017                        struct ref **matched_ref)
1018{
1019        int patlen = strlen(pattern);
1020        struct ref *matched_weak = NULL;
1021        struct ref *matched = NULL;
1022        int weak_match = 0;
1023        int match = 0;
1024
1025        for (weak_match = match = 0; refs; refs = refs->next) {
1026                char *name = refs->name;
1027                int namelen = strlen(name);
1028
1029                if (!refname_match(pattern, name))
1030                        continue;
1031
1032                /* A match is "weak" if it is with refs outside
1033                 * heads or tags, and did not specify the pattern
1034                 * in full (e.g. "refs/remotes/origin/master") or at
1035                 * least from the toplevel (e.g. "remotes/origin/master");
1036                 * otherwise "git push $URL master" would result in
1037                 * ambiguity between remotes/origin/master and heads/master
1038                 * at the remote site.
1039                 */
1040                if (namelen != patlen &&
1041                    patlen != namelen - 5 &&
1042                    !starts_with(name, "refs/heads/") &&
1043                    !starts_with(name, "refs/tags/")) {
1044                        /* We want to catch the case where only weak
1045                         * matches are found and there are multiple
1046                         * matches, and where more than one strong
1047                         * matches are found, as ambiguous.  One
1048                         * strong match with zero or more weak matches
1049                         * are acceptable as a unique match.
1050                         */
1051                        matched_weak = refs;
1052                        weak_match++;
1053                }
1054                else {
1055                        matched = refs;
1056                        match++;
1057                }
1058        }
1059        if (!matched) {
1060                if (matched_ref)
1061                        *matched_ref = matched_weak;
1062                return weak_match;
1063        }
1064        else {
1065                if (matched_ref)
1066                        *matched_ref = matched;
1067                return match;
1068        }
1069}
1070
1071static void tail_link_ref(struct ref *ref, struct ref ***tail)
1072{
1073        **tail = ref;
1074        while (ref->next)
1075                ref = ref->next;
1076        *tail = &ref->next;
1077}
1078
1079static struct ref *alloc_delete_ref(void)
1080{
1081        struct ref *ref = alloc_ref("(delete)");
1082        hashclr(ref->new_sha1);
1083        return ref;
1084}
1085
1086static int try_explicit_object_name(const char *name,
1087                                    struct ref **match)
1088{
1089        unsigned char sha1[20];
1090
1091        if (!*name) {
1092                if (match)
1093                        *match = alloc_delete_ref();
1094                return 0;
1095        }
1096
1097        if (get_sha1(name, sha1))
1098                return -1;
1099
1100        if (match) {
1101                *match = alloc_ref(name);
1102                hashcpy((*match)->new_sha1, sha1);
1103        }
1104        return 0;
1105}
1106
1107static struct ref *make_linked_ref(const char *name, struct ref ***tail)
1108{
1109        struct ref *ret = alloc_ref(name);
1110        tail_link_ref(ret, tail);
1111        return ret;
1112}
1113
1114static char *guess_ref(const char *name, struct ref *peer)
1115{
1116        struct strbuf buf = STRBUF_INIT;
1117        unsigned char sha1[20];
1118
1119        const char *r = resolve_ref_unsafe(peer->name, sha1, 1, NULL);
1120        if (!r)
1121                return NULL;
1122
1123        if (starts_with(r, "refs/heads/"))
1124                strbuf_addstr(&buf, "refs/heads/");
1125        else if (starts_with(r, "refs/tags/"))
1126                strbuf_addstr(&buf, "refs/tags/");
1127        else
1128                return NULL;
1129
1130        strbuf_addstr(&buf, name);
1131        return strbuf_detach(&buf, NULL);
1132}
1133
1134static int match_explicit_lhs(struct ref *src,
1135                              struct refspec *rs,
1136                              struct ref **match,
1137                              int *allocated_match)
1138{
1139        switch (count_refspec_match(rs->src, src, match)) {
1140        case 1:
1141                if (allocated_match)
1142                        *allocated_match = 0;
1143                return 0;
1144        case 0:
1145                /* The source could be in the get_sha1() format
1146                 * not a reference name.  :refs/other is a
1147                 * way to delete 'other' ref at the remote end.
1148                 */
1149                if (try_explicit_object_name(rs->src, match) < 0)
1150                        return error("src refspec %s does not match any.", rs->src);
1151                if (allocated_match)
1152                        *allocated_match = 1;
1153                return 0;
1154        default:
1155                return error("src refspec %s matches more than one.", rs->src);
1156        }
1157}
1158
1159static int match_explicit(struct ref *src, struct ref *dst,
1160                          struct ref ***dst_tail,
1161                          struct refspec *rs)
1162{
1163        struct ref *matched_src, *matched_dst;
1164        int allocated_src;
1165
1166        const char *dst_value = rs->dst;
1167        char *dst_guess;
1168
1169        if (rs->pattern || rs->matching)
1170                return 0;
1171
1172        matched_src = matched_dst = NULL;
1173        if (match_explicit_lhs(src, rs, &matched_src, &allocated_src) < 0)
1174                return -1;
1175
1176        if (!dst_value) {
1177                unsigned char sha1[20];
1178                int flag;
1179
1180                dst_value = resolve_ref_unsafe(matched_src->name, sha1, 1, &flag);
1181                if (!dst_value ||
1182                    ((flag & REF_ISSYMREF) &&
1183                     !starts_with(dst_value, "refs/heads/")))
1184                        die("%s cannot be resolved to branch.",
1185                            matched_src->name);
1186        }
1187
1188        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
1189        case 1:
1190                break;
1191        case 0:
1192                if (starts_with(dst_value, "refs/"))
1193                        matched_dst = make_linked_ref(dst_value, dst_tail);
1194                else if (is_null_sha1(matched_src->new_sha1))
1195                        error("unable to delete '%s': remote ref does not exist",
1196                              dst_value);
1197                else if ((dst_guess = guess_ref(dst_value, matched_src)))
1198                        matched_dst = make_linked_ref(dst_guess, dst_tail);
1199                else
1200                        error("unable to push to unqualified destination: %s\n"
1201                              "The destination refspec neither matches an "
1202                              "existing ref on the remote nor\n"
1203                              "begins with refs/, and we are unable to "
1204                              "guess a prefix based on the source ref.",
1205                              dst_value);
1206                break;
1207        default:
1208                matched_dst = NULL;
1209                error("dst refspec %s matches more than one.",
1210                      dst_value);
1211                break;
1212        }
1213        if (!matched_dst)
1214                return -1;
1215        if (matched_dst->peer_ref)
1216                return error("dst ref %s receives from more than one src.",
1217                      matched_dst->name);
1218        else {
1219                matched_dst->peer_ref = allocated_src ?
1220                                        matched_src :
1221                                        copy_ref(matched_src);
1222                matched_dst->force = rs->force;
1223        }
1224        return 0;
1225}
1226
1227static int match_explicit_refs(struct ref *src, struct ref *dst,
1228                               struct ref ***dst_tail, struct refspec *rs,
1229                               int rs_nr)
1230{
1231        int i, errs;
1232        for (i = errs = 0; i < rs_nr; i++)
1233                errs += match_explicit(src, dst, dst_tail, &rs[i]);
1234        return errs;
1235}
1236
1237static char *get_ref_match(const struct refspec *rs, int rs_nr, const struct ref *ref,
1238                int send_mirror, int direction, const struct refspec **ret_pat)
1239{
1240        const struct refspec *pat;
1241        char *name;
1242        int i;
1243        int matching_refs = -1;
1244        for (i = 0; i < rs_nr; i++) {
1245                if (rs[i].matching &&
1246                    (matching_refs == -1 || rs[i].force)) {
1247                        matching_refs = i;
1248                        continue;
1249                }
1250
1251                if (rs[i].pattern) {
1252                        const char *dst_side = rs[i].dst ? rs[i].dst : rs[i].src;
1253                        int match;
1254                        if (direction == FROM_SRC)
1255                                match = match_name_with_pattern(rs[i].src, ref->name, dst_side, &name);
1256                        else
1257                                match = match_name_with_pattern(dst_side, ref->name, rs[i].src, &name);
1258                        if (match) {
1259                                matching_refs = i;
1260                                break;
1261                        }
1262                }
1263        }
1264        if (matching_refs == -1)
1265                return NULL;
1266
1267        pat = rs + matching_refs;
1268        if (pat->matching) {
1269                /*
1270                 * "matching refs"; traditionally we pushed everything
1271                 * including refs outside refs/heads/ hierarchy, but
1272                 * that does not make much sense these days.
1273                 */
1274                if (!send_mirror && !starts_with(ref->name, "refs/heads/"))
1275                        return NULL;
1276                name = xstrdup(ref->name);
1277        }
1278        if (ret_pat)
1279                *ret_pat = pat;
1280        return name;
1281}
1282
1283static struct ref **tail_ref(struct ref **head)
1284{
1285        struct ref **tail = head;
1286        while (*tail)
1287                tail = &((*tail)->next);
1288        return tail;
1289}
1290
1291struct tips {
1292        struct commit **tip;
1293        int nr, alloc;
1294};
1295
1296static void add_to_tips(struct tips *tips, const unsigned char *sha1)
1297{
1298        struct commit *commit;
1299
1300        if (is_null_sha1(sha1))
1301                return;
1302        commit = lookup_commit_reference_gently(sha1, 1);
1303        if (!commit || (commit->object.flags & TMP_MARK))
1304                return;
1305        commit->object.flags |= TMP_MARK;
1306        ALLOC_GROW(tips->tip, tips->nr + 1, tips->alloc);
1307        tips->tip[tips->nr++] = commit;
1308}
1309
1310static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***dst_tail)
1311{
1312        struct string_list dst_tag = STRING_LIST_INIT_NODUP;
1313        struct string_list src_tag = STRING_LIST_INIT_NODUP;
1314        struct string_list_item *item;
1315        struct ref *ref;
1316        struct tips sent_tips;
1317
1318        /*
1319         * Collect everything we know they would have at the end of
1320         * this push, and collect all tags they have.
1321         */
1322        memset(&sent_tips, 0, sizeof(sent_tips));
1323        for (ref = *dst; ref; ref = ref->next) {
1324                if (ref->peer_ref &&
1325                    !is_null_sha1(ref->peer_ref->new_sha1))
1326                        add_to_tips(&sent_tips, ref->peer_ref->new_sha1);
1327                else
1328                        add_to_tips(&sent_tips, ref->old_sha1);
1329                if (starts_with(ref->name, "refs/tags/"))
1330                        string_list_append(&dst_tag, ref->name);
1331        }
1332        clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
1333
1334        sort_string_list(&dst_tag);
1335
1336        /* Collect tags they do not have. */
1337        for (ref = src; ref; ref = ref->next) {
1338                if (!starts_with(ref->name, "refs/tags/"))
1339                        continue; /* not a tag */
1340                if (string_list_has_string(&dst_tag, ref->name))
1341                        continue; /* they already have it */
1342                if (sha1_object_info(ref->new_sha1, NULL) != OBJ_TAG)
1343                        continue; /* be conservative */
1344                item = string_list_append(&src_tag, ref->name);
1345                item->util = ref;
1346        }
1347        string_list_clear(&dst_tag, 0);
1348
1349        /*
1350         * At this point, src_tag lists tags that are missing from
1351         * dst, and sent_tips lists the tips we are pushing or those
1352         * that we know they already have. An element in the src_tag
1353         * that is an ancestor of any of the sent_tips needs to be
1354         * sent to the other side.
1355         */
1356        if (sent_tips.nr) {
1357                for_each_string_list_item(item, &src_tag) {
1358                        struct ref *ref = item->util;
1359                        struct ref *dst_ref;
1360                        struct commit *commit;
1361
1362                        if (is_null_sha1(ref->new_sha1))
1363                                continue;
1364                        commit = lookup_commit_reference_gently(ref->new_sha1, 1);
1365                        if (!commit)
1366                                /* not pushing a commit, which is not an error */
1367                                continue;
1368
1369                        /*
1370                         * Is this tag, which they do not have, reachable from
1371                         * any of the commits we are sending?
1372                         */
1373                        if (!in_merge_bases_many(commit, sent_tips.nr, sent_tips.tip))
1374                                continue;
1375
1376                        /* Add it in */
1377                        dst_ref = make_linked_ref(ref->name, dst_tail);
1378                        hashcpy(dst_ref->new_sha1, ref->new_sha1);
1379                        dst_ref->peer_ref = copy_ref(ref);
1380                }
1381        }
1382        string_list_clear(&src_tag, 0);
1383        free(sent_tips.tip);
1384}
1385
1386struct ref *find_ref_by_name(const struct ref *list, const char *name)
1387{
1388        for ( ; list; list = list->next)
1389                if (!strcmp(list->name, name))
1390                        return (struct ref *)list;
1391        return NULL;
1392}
1393
1394static void prepare_ref_index(struct string_list *ref_index, struct ref *ref)
1395{
1396        for ( ; ref; ref = ref->next)
1397                string_list_append_nodup(ref_index, ref->name)->util = ref;
1398
1399        sort_string_list(ref_index);
1400}
1401
1402/*
1403 * Given only the set of local refs, sanity-check the set of push
1404 * refspecs. We can't catch all errors that match_push_refs would,
1405 * but we can catch some errors early before even talking to the
1406 * remote side.
1407 */
1408int check_push_refs(struct ref *src, int nr_refspec, const char **refspec_names)
1409{
1410        struct refspec *refspec = parse_push_refspec(nr_refspec, refspec_names);
1411        int ret = 0;
1412        int i;
1413
1414        for (i = 0; i < nr_refspec; i++) {
1415                struct refspec *rs = refspec + i;
1416
1417                if (rs->pattern || rs->matching)
1418                        continue;
1419
1420                ret |= match_explicit_lhs(src, rs, NULL, NULL);
1421        }
1422
1423        free_refspec(nr_refspec, refspec);
1424        return ret;
1425}
1426
1427/*
1428 * Given the set of refs the local repository has, the set of refs the
1429 * remote repository has, and the refspec used for push, determine
1430 * what remote refs we will update and with what value by setting
1431 * peer_ref (which object is being pushed) and force (if the push is
1432 * forced) in elements of "dst". The function may add new elements to
1433 * dst (e.g. pushing to a new branch, done in match_explicit_refs).
1434 */
1435int match_push_refs(struct ref *src, struct ref **dst,
1436                    int nr_refspec, const char **refspec, int flags)
1437{
1438        struct refspec *rs;
1439        int send_all = flags & MATCH_REFS_ALL;
1440        int send_mirror = flags & MATCH_REFS_MIRROR;
1441        int send_prune = flags & MATCH_REFS_PRUNE;
1442        int errs;
1443        static const char *default_refspec[] = { ":", NULL };
1444        struct ref *ref, **dst_tail = tail_ref(dst);
1445        struct string_list dst_ref_index = STRING_LIST_INIT_NODUP;
1446
1447        if (!nr_refspec) {
1448                nr_refspec = 1;
1449                refspec = default_refspec;
1450        }
1451        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1452        errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
1453
1454        /* pick the remainder */
1455        for (ref = src; ref; ref = ref->next) {
1456                struct string_list_item *dst_item;
1457                struct ref *dst_peer;
1458                const struct refspec *pat = NULL;
1459                char *dst_name;
1460
1461                dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
1462                if (!dst_name)
1463                        continue;
1464
1465                if (!dst_ref_index.nr)
1466                        prepare_ref_index(&dst_ref_index, *dst);
1467
1468                dst_item = string_list_lookup(&dst_ref_index, dst_name);
1469                dst_peer = dst_item ? dst_item->util : NULL;
1470                if (dst_peer) {
1471                        if (dst_peer->peer_ref)
1472                                /* We're already sending something to this ref. */
1473                                goto free_name;
1474                } else {
1475                        if (pat->matching && !(send_all || send_mirror))
1476                                /*
1477                                 * Remote doesn't have it, and we have no
1478                                 * explicit pattern, and we don't have
1479                                 * --all or --mirror.
1480                                 */
1481                                goto free_name;
1482
1483                        /* Create a new one and link it */
1484                        dst_peer = make_linked_ref(dst_name, &dst_tail);
1485                        hashcpy(dst_peer->new_sha1, ref->new_sha1);
1486                        string_list_insert(&dst_ref_index,
1487                                dst_peer->name)->util = dst_peer;
1488                }
1489                dst_peer->peer_ref = copy_ref(ref);
1490                dst_peer->force = pat->force;
1491        free_name:
1492                free(dst_name);
1493        }
1494
1495        string_list_clear(&dst_ref_index, 0);
1496
1497        if (flags & MATCH_REFS_FOLLOW_TAGS)
1498                add_missing_tags(src, dst, &dst_tail);
1499
1500        if (send_prune) {
1501                struct string_list src_ref_index = STRING_LIST_INIT_NODUP;
1502                /* check for missing refs on the remote */
1503                for (ref = *dst; ref; ref = ref->next) {
1504                        char *src_name;
1505
1506                        if (ref->peer_ref)
1507                                /* We're already sending something to this ref. */
1508                                continue;
1509
1510                        src_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_DST, NULL);
1511                        if (src_name) {
1512                                if (!src_ref_index.nr)
1513                                        prepare_ref_index(&src_ref_index, src);
1514                                if (!string_list_has_string(&src_ref_index,
1515                                            src_name))
1516                                        ref->peer_ref = alloc_delete_ref();
1517                                free(src_name);
1518                        }
1519                }
1520                string_list_clear(&src_ref_index, 0);
1521        }
1522        if (errs)
1523                return -1;
1524        return 0;
1525}
1526
1527void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
1528                             int force_update)
1529{
1530        struct ref *ref;
1531
1532        for (ref = remote_refs; ref; ref = ref->next) {
1533                int force_ref_update = ref->force || force_update;
1534                int reject_reason = 0;
1535
1536                if (ref->peer_ref)
1537                        hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
1538                else if (!send_mirror)
1539                        continue;
1540
1541                ref->deletion = is_null_sha1(ref->new_sha1);
1542                if (!ref->deletion &&
1543                        !hashcmp(ref->old_sha1, ref->new_sha1)) {
1544                        ref->status = REF_STATUS_UPTODATE;
1545                        continue;
1546                }
1547
1548                /*
1549                 * Bypass the usual "must fast-forward" check but
1550                 * replace it with a weaker "the old value must be
1551                 * this value we observed".  If the remote ref has
1552                 * moved and is now different from what we expect,
1553                 * reject any push.
1554                 *
1555                 * It also is an error if the user told us to check
1556                 * with the remote-tracking branch to find the value
1557                 * to expect, but we did not have such a tracking
1558                 * branch.
1559                 */
1560                if (ref->expect_old_sha1) {
1561                        if (ref->expect_old_no_trackback ||
1562                            hashcmp(ref->old_sha1, ref->old_sha1_expect))
1563                                reject_reason = REF_STATUS_REJECT_STALE;
1564                }
1565
1566                /*
1567                 * The usual "must fast-forward" rules.
1568                 *
1569                 * Decide whether an individual refspec A:B can be
1570                 * pushed.  The push will succeed if any of the
1571                 * following are true:
1572                 *
1573                 * (1) the remote reference B does not exist
1574                 *
1575                 * (2) the remote reference B is being removed (i.e.,
1576                 *     pushing :B where no source is specified)
1577                 *
1578                 * (3) the destination is not under refs/tags/, and
1579                 *     if the old and new value is a commit, the new
1580                 *     is a descendant of the old.
1581                 *
1582                 * (4) it is forced using the +A:B notation, or by
1583                 *     passing the --force argument
1584                 */
1585
1586                else if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
1587                        if (starts_with(ref->name, "refs/tags/"))
1588                                reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
1589                        else if (!has_sha1_file(ref->old_sha1))
1590                                reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
1591                        else if (!lookup_commit_reference_gently(ref->old_sha1, 1) ||
1592                                 !lookup_commit_reference_gently(ref->new_sha1, 1))
1593                                reject_reason = REF_STATUS_REJECT_NEEDS_FORCE;
1594                        else if (!ref_newer(ref->new_sha1, ref->old_sha1))
1595                                reject_reason = REF_STATUS_REJECT_NONFASTFORWARD;
1596                }
1597
1598                /*
1599                 * "--force" will defeat any rejection implemented
1600                 * by the rules above.
1601                 */
1602                if (!force_ref_update)
1603                        ref->status = reject_reason;
1604                else if (reject_reason)
1605                        ref->forced_update = 1;
1606        }
1607}
1608
1609struct branch *branch_get(const char *name)
1610{
1611        struct branch *ret;
1612
1613        read_config();
1614        if (!name || !*name || !strcmp(name, "HEAD"))
1615                ret = current_branch;
1616        else
1617                ret = make_branch(name, 0);
1618        if (ret && ret->remote_name) {
1619                ret->remote = remote_get(ret->remote_name);
1620                if (ret->merge_nr) {
1621                        int i;
1622                        ret->merge = xcalloc(ret->merge_nr, sizeof(*ret->merge));
1623                        for (i = 0; i < ret->merge_nr; i++) {
1624                                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1625                                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1626                                if (remote_find_tracking(ret->remote, ret->merge[i])
1627                                    && !strcmp(ret->remote_name, "."))
1628                                        ret->merge[i]->dst = xstrdup(ret->merge_name[i]);
1629                        }
1630                }
1631        }
1632        return ret;
1633}
1634
1635int branch_has_merge_config(struct branch *branch)
1636{
1637        return branch && !!branch->merge;
1638}
1639
1640int branch_merge_matches(struct branch *branch,
1641                                 int i,
1642                                 const char *refname)
1643{
1644        if (!branch || i < 0 || i >= branch->merge_nr)
1645                return 0;
1646        return refname_match(branch->merge[i]->src, refname);
1647}
1648
1649static int ignore_symref_update(const char *refname)
1650{
1651        unsigned char sha1[20];
1652        int flag;
1653
1654        if (!resolve_ref_unsafe(refname, sha1, 0, &flag))
1655                return 0; /* non-existing refs are OK */
1656        return (flag & REF_ISSYMREF);
1657}
1658
1659/*
1660 * Create and return a list of (struct ref) consisting of copies of
1661 * each remote_ref that matches refspec.  refspec must be a pattern.
1662 * Fill in the copies' peer_ref to describe the local tracking refs to
1663 * which they map.  Omit any references that would map to an existing
1664 * local symbolic ref.
1665 */
1666static struct ref *get_expanded_map(const struct ref *remote_refs,
1667                                    const struct refspec *refspec)
1668{
1669        const struct ref *ref;
1670        struct ref *ret = NULL;
1671        struct ref **tail = &ret;
1672
1673        for (ref = remote_refs; ref; ref = ref->next) {
1674                char *expn_name = NULL;
1675
1676                if (strchr(ref->name, '^'))
1677                        continue; /* a dereference item */
1678                if (match_name_with_pattern(refspec->src, ref->name,
1679                                            refspec->dst, &expn_name) &&
1680                    !ignore_symref_update(expn_name)) {
1681                        struct ref *cpy = copy_ref(ref);
1682
1683                        cpy->peer_ref = alloc_ref(expn_name);
1684                        if (refspec->force)
1685                                cpy->peer_ref->force = 1;
1686                        *tail = cpy;
1687                        tail = &cpy->next;
1688                }
1689                free(expn_name);
1690        }
1691
1692        return ret;
1693}
1694
1695static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1696{
1697        const struct ref *ref;
1698        for (ref = refs; ref; ref = ref->next) {
1699                if (refname_match(name, ref->name))
1700                        return ref;
1701        }
1702        return NULL;
1703}
1704
1705struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1706{
1707        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1708
1709        if (!ref)
1710                return NULL;
1711
1712        return copy_ref(ref);
1713}
1714
1715static struct ref *get_local_ref(const char *name)
1716{
1717        if (!name || name[0] == '\0')
1718                return NULL;
1719
1720        if (starts_with(name, "refs/"))
1721                return alloc_ref(name);
1722
1723        if (starts_with(name, "heads/") ||
1724            starts_with(name, "tags/") ||
1725            starts_with(name, "remotes/"))
1726                return alloc_ref_with_prefix("refs/", 5, name);
1727
1728        return alloc_ref_with_prefix("refs/heads/", 11, name);
1729}
1730
1731int get_fetch_map(const struct ref *remote_refs,
1732                  const struct refspec *refspec,
1733                  struct ref ***tail,
1734                  int missing_ok)
1735{
1736        struct ref *ref_map, **rmp;
1737
1738        if (refspec->pattern) {
1739                ref_map = get_expanded_map(remote_refs, refspec);
1740        } else {
1741                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1742
1743                if (refspec->exact_sha1) {
1744                        ref_map = alloc_ref(name);
1745                        get_sha1_hex(name, ref_map->old_sha1);
1746                } else {
1747                        ref_map = get_remote_ref(remote_refs, name);
1748                }
1749                if (!missing_ok && !ref_map)
1750                        die("Couldn't find remote ref %s", name);
1751                if (ref_map) {
1752                        ref_map->peer_ref = get_local_ref(refspec->dst);
1753                        if (ref_map->peer_ref && refspec->force)
1754                                ref_map->peer_ref->force = 1;
1755                }
1756        }
1757
1758        for (rmp = &ref_map; *rmp; ) {
1759                if ((*rmp)->peer_ref) {
1760                        if (!starts_with((*rmp)->peer_ref->name, "refs/") ||
1761                            check_refname_format((*rmp)->peer_ref->name, 0)) {
1762                                struct ref *ignore = *rmp;
1763                                error("* Ignoring funny ref '%s' locally",
1764                                      (*rmp)->peer_ref->name);
1765                                *rmp = (*rmp)->next;
1766                                free(ignore->peer_ref);
1767                                free(ignore);
1768                                continue;
1769                        }
1770                }
1771                rmp = &((*rmp)->next);
1772        }
1773
1774        if (ref_map)
1775                tail_link_ref(ref_map, tail);
1776
1777        return 0;
1778}
1779
1780int resolve_remote_symref(struct ref *ref, struct ref *list)
1781{
1782        if (!ref->symref)
1783                return 0;
1784        for (; list; list = list->next)
1785                if (!strcmp(ref->symref, list->name)) {
1786                        hashcpy(ref->old_sha1, list->old_sha1);
1787                        return 0;
1788                }
1789        return 1;
1790}
1791
1792static void unmark_and_free(struct commit_list *list, unsigned int mark)
1793{
1794        while (list) {
1795                struct commit_list *temp = list;
1796                temp->item->object.flags &= ~mark;
1797                list = temp->next;
1798                free(temp);
1799        }
1800}
1801
1802int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
1803{
1804        struct object *o;
1805        struct commit *old, *new;
1806        struct commit_list *list, *used;
1807        int found = 0;
1808
1809        /*
1810         * Both new and old must be commit-ish and new is descendant of
1811         * old.  Otherwise we require --force.
1812         */
1813        o = deref_tag(parse_object(old_sha1), NULL, 0);
1814        if (!o || o->type != OBJ_COMMIT)
1815                return 0;
1816        old = (struct commit *) o;
1817
1818        o = deref_tag(parse_object(new_sha1), NULL, 0);
1819        if (!o || o->type != OBJ_COMMIT)
1820                return 0;
1821        new = (struct commit *) o;
1822
1823        if (parse_commit(new) < 0)
1824                return 0;
1825
1826        used = list = NULL;
1827        commit_list_insert(new, &list);
1828        while (list) {
1829                new = pop_most_recent_commit(&list, TMP_MARK);
1830                commit_list_insert(new, &used);
1831                if (new == old) {
1832                        found = 1;
1833                        break;
1834                }
1835        }
1836        unmark_and_free(list, TMP_MARK);
1837        unmark_and_free(used, TMP_MARK);
1838        return found;
1839}
1840
1841/*
1842 * Compare a branch with its upstream, and save their differences (number
1843 * of commits) in *num_ours and *num_theirs.
1844 *
1845 * Return 0 if branch has no upstream (no base), -1 if upstream is missing
1846 * (with "gone" base), otherwise 1 (with base).
1847 */
1848int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
1849{
1850        unsigned char sha1[20];
1851        struct commit *ours, *theirs;
1852        char symmetric[84];
1853        struct rev_info revs;
1854        const char *rev_argv[10], *base;
1855        int rev_argc;
1856
1857        /* Cannot stat unless we are marked to build on top of somebody else. */
1858        if (!branch ||
1859            !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
1860                return 0;
1861
1862        /* Cannot stat if what we used to build on no longer exists */
1863        base = branch->merge[0]->dst;
1864        if (read_ref(base, sha1))
1865                return -1;
1866        theirs = lookup_commit_reference(sha1);
1867        if (!theirs)
1868                return -1;
1869
1870        if (read_ref(branch->refname, sha1))
1871                return -1;
1872        ours = lookup_commit_reference(sha1);
1873        if (!ours)
1874                return -1;
1875
1876        /* are we the same? */
1877        if (theirs == ours) {
1878                *num_theirs = *num_ours = 0;
1879                return 1;
1880        }
1881
1882        /* Run "rev-list --left-right ours...theirs" internally... */
1883        rev_argc = 0;
1884        rev_argv[rev_argc++] = NULL;
1885        rev_argv[rev_argc++] = "--left-right";
1886        rev_argv[rev_argc++] = symmetric;
1887        rev_argv[rev_argc++] = "--";
1888        rev_argv[rev_argc] = NULL;
1889
1890        strcpy(symmetric, sha1_to_hex(ours->object.sha1));
1891        strcpy(symmetric + 40, "...");
1892        strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
1893
1894        init_revisions(&revs, NULL);
1895        setup_revisions(rev_argc, rev_argv, &revs, NULL);
1896        prepare_revision_walk(&revs);
1897
1898        /* ... and count the commits on each side. */
1899        *num_ours = 0;
1900        *num_theirs = 0;
1901        while (1) {
1902                struct commit *c = get_revision(&revs);
1903                if (!c)
1904                        break;
1905                if (c->object.flags & SYMMETRIC_LEFT)
1906                        (*num_ours)++;
1907                else
1908                        (*num_theirs)++;
1909        }
1910
1911        /* clear object flags smudged by the above traversal */
1912        clear_commit_marks(ours, ALL_REV_FLAGS);
1913        clear_commit_marks(theirs, ALL_REV_FLAGS);
1914        return 1;
1915}
1916
1917/*
1918 * Return true when there is anything to report, otherwise false.
1919 */
1920int format_tracking_info(struct branch *branch, struct strbuf *sb)
1921{
1922        int ours, theirs;
1923        const char *base;
1924        int upstream_is_gone = 0;
1925
1926        switch (stat_tracking_info(branch, &ours, &theirs)) {
1927        case 0:
1928                /* no base */
1929                return 0;
1930        case -1:
1931                /* with "gone" base */
1932                upstream_is_gone = 1;
1933                break;
1934        default:
1935                /* with base */
1936                break;
1937        }
1938
1939        base = branch->merge[0]->dst;
1940        base = shorten_unambiguous_ref(base, 0);
1941        if (upstream_is_gone) {
1942                strbuf_addf(sb,
1943                        _("Your branch is based on '%s', but the upstream is gone.\n"),
1944                        base);
1945                if (advice_status_hints)
1946                        strbuf_addf(sb,
1947                                _("  (use \"git branch --unset-upstream\" to fixup)\n"));
1948        } else if (!ours && !theirs) {
1949                strbuf_addf(sb,
1950                        _("Your branch is up-to-date with '%s'.\n"),
1951                        base);
1952        } else if (!theirs) {
1953                strbuf_addf(sb,
1954                        Q_("Your branch is ahead of '%s' by %d commit.\n",
1955                           "Your branch is ahead of '%s' by %d commits.\n",
1956                           ours),
1957                        base, ours);
1958                if (advice_status_hints)
1959                        strbuf_addf(sb,
1960                                _("  (use \"git push\" to publish your local commits)\n"));
1961        } else if (!ours) {
1962                strbuf_addf(sb,
1963                        Q_("Your branch is behind '%s' by %d commit, "
1964                               "and can be fast-forwarded.\n",
1965                           "Your branch is behind '%s' by %d commits, "
1966                               "and can be fast-forwarded.\n",
1967                           theirs),
1968                        base, theirs);
1969                if (advice_status_hints)
1970                        strbuf_addf(sb,
1971                                _("  (use \"git pull\" to update your local branch)\n"));
1972        } else {
1973                strbuf_addf(sb,
1974                        Q_("Your branch and '%s' have diverged,\n"
1975                               "and have %d and %d different commit each, "
1976                               "respectively.\n",
1977                           "Your branch and '%s' have diverged,\n"
1978                               "and have %d and %d different commits each, "
1979                               "respectively.\n",
1980                           theirs),
1981                        base, ours, theirs);
1982                if (advice_status_hints)
1983                        strbuf_addf(sb,
1984                                _("  (use \"git pull\" to merge the remote branch into yours)\n"));
1985        }
1986        return 1;
1987}
1988
1989static int one_local_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
1990{
1991        struct ref ***local_tail = cb_data;
1992        struct ref *ref;
1993        int len;
1994
1995        /* we already know it starts with refs/ to get here */
1996        if (check_refname_format(refname + 5, 0))
1997                return 0;
1998
1999        len = strlen(refname) + 1;
2000        ref = xcalloc(1, sizeof(*ref) + len);
2001        hashcpy(ref->new_sha1, sha1);
2002        memcpy(ref->name, refname, len);
2003        **local_tail = ref;
2004        *local_tail = &ref->next;
2005        return 0;
2006}
2007
2008struct ref *get_local_heads(void)
2009{
2010        struct ref *local_refs = NULL, **local_tail = &local_refs;
2011        for_each_ref(one_local_ref, &local_tail);
2012        return local_refs;
2013}
2014
2015struct ref *guess_remote_head(const struct ref *head,
2016                              const struct ref *refs,
2017                              int all)
2018{
2019        const struct ref *r;
2020        struct ref *list = NULL;
2021        struct ref **tail = &list;
2022
2023        if (!head)
2024                return NULL;
2025
2026        /*
2027         * Some transports support directly peeking at
2028         * where HEAD points; if that is the case, then
2029         * we don't have to guess.
2030         */
2031        if (head->symref)
2032                return copy_ref(find_ref_by_name(refs, head->symref));
2033
2034        /* If refs/heads/master could be right, it is. */
2035        if (!all) {
2036                r = find_ref_by_name(refs, "refs/heads/master");
2037                if (r && !hashcmp(r->old_sha1, head->old_sha1))
2038                        return copy_ref(r);
2039        }
2040
2041        /* Look for another ref that points there */
2042        for (r = refs; r; r = r->next) {
2043                if (r != head &&
2044                    starts_with(r->name, "refs/heads/") &&
2045                    !hashcmp(r->old_sha1, head->old_sha1)) {
2046                        *tail = copy_ref(r);
2047                        tail = &((*tail)->next);
2048                        if (!all)
2049                                break;
2050                }
2051        }
2052
2053        return list;
2054}
2055
2056struct stale_heads_info {
2057        struct string_list *ref_names;
2058        struct ref **stale_refs_tail;
2059        struct refspec *refs;
2060        int ref_count;
2061};
2062
2063static int get_stale_heads_cb(const char *refname,
2064        const unsigned char *sha1, int flags, void *cb_data)
2065{
2066        struct stale_heads_info *info = cb_data;
2067        struct string_list matches = STRING_LIST_INIT_DUP;
2068        struct refspec query;
2069        int i, stale = 1;
2070        memset(&query, 0, sizeof(struct refspec));
2071        query.dst = (char *)refname;
2072
2073        query_refspecs_multiple(info->refs, info->ref_count, &query, &matches);
2074        if (matches.nr == 0)
2075                goto clean_exit; /* No matches */
2076
2077        /*
2078         * If we did find a suitable refspec and it's not a symref and
2079         * it's not in the list of refs that currently exist in that
2080         * remote, we consider it to be stale. In order to deal with
2081         * overlapping refspecs, we need to go over all of the
2082         * matching refs.
2083         */
2084        if (flags & REF_ISSYMREF)
2085                goto clean_exit;
2086
2087        for (i = 0; stale && i < matches.nr; i++)
2088                if (string_list_has_string(info->ref_names, matches.items[i].string))
2089                        stale = 0;
2090
2091        if (stale) {
2092                struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
2093                hashcpy(ref->new_sha1, sha1);
2094        }
2095
2096clean_exit:
2097        string_list_clear(&matches, 0);
2098        return 0;
2099}
2100
2101struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fetch_map)
2102{
2103        struct ref *ref, *stale_refs = NULL;
2104        struct string_list ref_names = STRING_LIST_INIT_NODUP;
2105        struct stale_heads_info info;
2106        info.ref_names = &ref_names;
2107        info.stale_refs_tail = &stale_refs;
2108        info.refs = refs;
2109        info.ref_count = ref_count;
2110        for (ref = fetch_map; ref; ref = ref->next)
2111                string_list_append(&ref_names, ref->name);
2112        sort_string_list(&ref_names);
2113        for_each_ref(get_stale_heads_cb, &info);
2114        string_list_clear(&ref_names, 0);
2115        return stale_refs;
2116}
2117
2118/*
2119 * Compare-and-swap
2120 */
2121void clear_cas_option(struct push_cas_option *cas)
2122{
2123        int i;
2124
2125        for (i = 0; i < cas->nr; i++)
2126                free(cas->entry[i].refname);
2127        free(cas->entry);
2128        memset(cas, 0, sizeof(*cas));
2129}
2130
2131static struct push_cas *add_cas_entry(struct push_cas_option *cas,
2132                                      const char *refname,
2133                                      size_t refnamelen)
2134{
2135        struct push_cas *entry;
2136        ALLOC_GROW(cas->entry, cas->nr + 1, cas->alloc);
2137        entry = &cas->entry[cas->nr++];
2138        memset(entry, 0, sizeof(*entry));
2139        entry->refname = xmemdupz(refname, refnamelen);
2140        return entry;
2141}
2142
2143int parse_push_cas_option(struct push_cas_option *cas, const char *arg, int unset)
2144{
2145        const char *colon;
2146        struct push_cas *entry;
2147
2148        if (unset) {
2149                /* "--no-<option>" */
2150                clear_cas_option(cas);
2151                return 0;
2152        }
2153
2154        if (!arg) {
2155                /* just "--<option>" */
2156                cas->use_tracking_for_rest = 1;
2157                return 0;
2158        }
2159
2160        /* "--<option>=refname" or "--<option>=refname:value" */
2161        colon = strchrnul(arg, ':');
2162        entry = add_cas_entry(cas, arg, colon - arg);
2163        if (!*colon)
2164                entry->use_tracking = 1;
2165        else if (get_sha1(colon + 1, entry->expect))
2166                return error("cannot parse expected object name '%s'", colon + 1);
2167        return 0;
2168}
2169
2170int parseopt_push_cas_option(const struct option *opt, const char *arg, int unset)
2171{
2172        return parse_push_cas_option(opt->value, arg, unset);
2173}
2174
2175int is_empty_cas(const struct push_cas_option *cas)
2176{
2177        return !cas->use_tracking_for_rest && !cas->nr;
2178}
2179
2180/*
2181 * Look at remote.fetch refspec and see if we have a remote
2182 * tracking branch for the refname there.  Fill its current
2183 * value in sha1[].
2184 * If we cannot do so, return negative to signal an error.
2185 */
2186static int remote_tracking(struct remote *remote, const char *refname,
2187                           unsigned char sha1[20])
2188{
2189        char *dst;
2190
2191        dst = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
2192        if (!dst)
2193                return -1; /* no tracking ref for refname at remote */
2194        if (read_ref(dst, sha1))
2195                return -1; /* we know what the tracking ref is but we cannot read it */
2196        return 0;
2197}
2198
2199static void apply_cas(struct push_cas_option *cas,
2200                      struct remote *remote,
2201                      struct ref *ref)
2202{
2203        int i;
2204
2205        /* Find an explicit --<option>=<name>[:<value>] entry */
2206        for (i = 0; i < cas->nr; i++) {
2207                struct push_cas *entry = &cas->entry[i];
2208                if (!refname_match(entry->refname, ref->name))
2209                        continue;
2210                ref->expect_old_sha1 = 1;
2211                if (!entry->use_tracking)
2212                        hashcpy(ref->old_sha1_expect, cas->entry[i].expect);
2213                else if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2214                        ref->expect_old_no_trackback = 1;
2215                return;
2216        }
2217
2218        /* Are we using "--<option>" to cover all? */
2219        if (!cas->use_tracking_for_rest)
2220                return;
2221
2222        ref->expect_old_sha1 = 1;
2223        if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2224                ref->expect_old_no_trackback = 1;
2225}
2226
2227void apply_push_cas(struct push_cas_option *cas,
2228                    struct remote *remote,
2229                    struct ref *remote_refs)
2230{
2231        struct ref *ref;
2232        for (ref = remote_refs; ref; ref = ref->next)
2233                apply_cas(cas, remote, ref);
2234}