remote.con commit wincred: add install target (ccfb5bd)
   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        char *refname;
 174
 175        for (i = 0; i < branches_nr; i++) {
 176                if (len ? (!strncmp(name, branches[i]->name, len) &&
 177                           !branches[i]->name[len]) :
 178                    !strcmp(name, branches[i]->name))
 179                        return branches[i];
 180        }
 181
 182        ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 183        ret = xcalloc(1, sizeof(struct branch));
 184        branches[branches_nr++] = ret;
 185        if (len)
 186                ret->name = xstrndup(name, len);
 187        else
 188                ret->name = xstrdup(name);
 189        refname = xmalloc(strlen(name) + strlen("refs/heads/") + 1);
 190        strcpy(refname, "refs/heads/");
 191        strcpy(refname + strlen("refs/heads/"), ret->name);
 192        ret->refname = refname;
 193
 194        return ret;
 195}
 196
 197static struct rewrite *make_rewrite(struct rewrites *r, const char *base, int len)
 198{
 199        struct rewrite *ret;
 200        int i;
 201
 202        for (i = 0; i < r->rewrite_nr; i++) {
 203                if (len
 204                    ? (len == r->rewrite[i]->baselen &&
 205                       !strncmp(base, r->rewrite[i]->base, len))
 206                    : !strcmp(base, r->rewrite[i]->base))
 207                        return r->rewrite[i];
 208        }
 209
 210        ALLOC_GROW(r->rewrite, r->rewrite_nr + 1, r->rewrite_alloc);
 211        ret = xcalloc(1, sizeof(struct rewrite));
 212        r->rewrite[r->rewrite_nr++] = ret;
 213        if (len) {
 214                ret->base = xstrndup(base, len);
 215                ret->baselen = len;
 216        }
 217        else {
 218                ret->base = xstrdup(base);
 219                ret->baselen = strlen(base);
 220        }
 221        return ret;
 222}
 223
 224static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 225{
 226        ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 227        rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 228        rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 229        rewrite->instead_of_nr++;
 230}
 231
 232static void read_remotes_file(struct remote *remote)
 233{
 234        FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
 235
 236        if (!f)
 237                return;
 238        remote->origin = REMOTE_REMOTES;
 239        while (fgets(buffer, BUF_SIZE, f)) {
 240                int value_list;
 241                char *s, *p;
 242
 243                if (starts_with(buffer, "URL:")) {
 244                        value_list = 0;
 245                        s = buffer + 4;
 246                } else if (starts_with(buffer, "Push:")) {
 247                        value_list = 1;
 248                        s = buffer + 5;
 249                } else if (starts_with(buffer, "Pull:")) {
 250                        value_list = 2;
 251                        s = buffer + 5;
 252                } else
 253                        continue;
 254
 255                while (isspace(*s))
 256                        s++;
 257                if (!*s)
 258                        continue;
 259
 260                p = s + strlen(s);
 261                while (isspace(p[-1]))
 262                        *--p = 0;
 263
 264                switch (value_list) {
 265                case 0:
 266                        add_url_alias(remote, xstrdup(s));
 267                        break;
 268                case 1:
 269                        add_push_refspec(remote, xstrdup(s));
 270                        break;
 271                case 2:
 272                        add_fetch_refspec(remote, xstrdup(s));
 273                        break;
 274                }
 275        }
 276        fclose(f);
 277}
 278
 279static void read_branches_file(struct remote *remote)
 280{
 281        char *frag;
 282        struct strbuf branch = STRBUF_INIT;
 283        int n = 1000;
 284        FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 285        char *s, *p;
 286        int len;
 287
 288        if (!f)
 289                return;
 290        s = fgets(buffer, BUF_SIZE, f);
 291        fclose(f);
 292        if (!s)
 293                return;
 294        while (isspace(*s))
 295                s++;
 296        if (!*s)
 297                return;
 298        remote->origin = REMOTE_BRANCHES;
 299        p = s + strlen(s);
 300        while (isspace(p[-1]))
 301                *--p = 0;
 302        len = p - s;
 303        p = xmalloc(len + 1);
 304        strcpy(p, s);
 305
 306        /*
 307         * The branches file would have URL and optionally
 308         * #branch specified.  The "master" (or specified) branch is
 309         * fetched and stored in the local branch of the same name.
 310         */
 311        frag = strchr(p, '#');
 312        if (frag) {
 313                *(frag++) = '\0';
 314                strbuf_addf(&branch, "refs/heads/%s", frag);
 315        } else
 316                strbuf_addstr(&branch, "refs/heads/master");
 317
 318        strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 319        add_url_alias(remote, p);
 320        add_fetch_refspec(remote, strbuf_detach(&branch, NULL));
 321        /*
 322         * Cogito compatible push: push current HEAD to remote #branch
 323         * (master if missing)
 324         */
 325        strbuf_init(&branch, 0);
 326        strbuf_addstr(&branch, "HEAD");
 327        if (frag)
 328                strbuf_addf(&branch, ":refs/heads/%s", frag);
 329        else
 330                strbuf_addstr(&branch, ":refs/heads/master");
 331        add_push_refspec(remote, strbuf_detach(&branch, NULL));
 332        remote->fetch_tags = 1; /* always auto-follow */
 333}
 334
 335static int handle_config(const char *key, const char *value, void *cb)
 336{
 337        const char *name;
 338        const char *subkey;
 339        struct remote *remote;
 340        struct branch *branch;
 341        if (starts_with(key, "branch.")) {
 342                name = key + 7;
 343                subkey = strrchr(name, '.');
 344                if (!subkey)
 345                        return 0;
 346                branch = make_branch(name, subkey - name);
 347                if (!strcmp(subkey, ".remote")) {
 348                        if (git_config_string(&branch->remote_name, key, value))
 349                                return -1;
 350                        if (branch == current_branch) {
 351                                default_remote_name = branch->remote_name;
 352                                explicit_default_remote_name = 1;
 353                        }
 354                } else if (!strcmp(subkey, ".pushremote")) {
 355                        if (branch == current_branch)
 356                                if (git_config_string(&branch_pushremote_name, key, value))
 357                                        return -1;
 358                } else if (!strcmp(subkey, ".merge")) {
 359                        if (!value)
 360                                return config_error_nonbool(key);
 361                        add_merge(branch, xstrdup(value));
 362                }
 363                return 0;
 364        }
 365        if (starts_with(key, "url.")) {
 366                struct rewrite *rewrite;
 367                name = key + 4;
 368                subkey = strrchr(name, '.');
 369                if (!subkey)
 370                        return 0;
 371                if (!strcmp(subkey, ".insteadof")) {
 372                        rewrite = make_rewrite(&rewrites, name, subkey - name);
 373                        if (!value)
 374                                return config_error_nonbool(key);
 375                        add_instead_of(rewrite, xstrdup(value));
 376                } else if (!strcmp(subkey, ".pushinsteadof")) {
 377                        rewrite = make_rewrite(&rewrites_push, name, subkey - name);
 378                        if (!value)
 379                                return config_error_nonbool(key);
 380                        add_instead_of(rewrite, xstrdup(value));
 381                }
 382        }
 383
 384        if (!starts_with(key,  "remote."))
 385                return 0;
 386        name = key + 7;
 387
 388        /* Handle remote.* variables */
 389        if (!strcmp(name, "pushdefault"))
 390                return git_config_string(&pushremote_name, key, value);
 391
 392        /* Handle remote.<name>.* variables */
 393        if (*name == '/') {
 394                warning("Config remote shorthand cannot begin with '/': %s",
 395                        name);
 396                return 0;
 397        }
 398        subkey = strrchr(name, '.');
 399        if (!subkey)
 400                return 0;
 401        remote = make_remote(name, subkey - name);
 402        remote->origin = REMOTE_CONFIG;
 403        if (!strcmp(subkey, ".mirror"))
 404                remote->mirror = git_config_bool(key, value);
 405        else if (!strcmp(subkey, ".skipdefaultupdate"))
 406                remote->skip_default_update = git_config_bool(key, value);
 407        else if (!strcmp(subkey, ".skipfetchall"))
 408                remote->skip_default_update = git_config_bool(key, value);
 409        else if (!strcmp(subkey, ".prune"))
 410                remote->prune = git_config_bool(key, value);
 411        else if (!strcmp(subkey, ".url")) {
 412                const char *v;
 413                if (git_config_string(&v, key, value))
 414                        return -1;
 415                add_url(remote, v);
 416        } else if (!strcmp(subkey, ".pushurl")) {
 417                const char *v;
 418                if (git_config_string(&v, key, value))
 419                        return -1;
 420                add_pushurl(remote, v);
 421        } else if (!strcmp(subkey, ".push")) {
 422                const char *v;
 423                if (git_config_string(&v, key, value))
 424                        return -1;
 425                add_push_refspec(remote, v);
 426        } else if (!strcmp(subkey, ".fetch")) {
 427                const char *v;
 428                if (git_config_string(&v, key, value))
 429                        return -1;
 430                add_fetch_refspec(remote, v);
 431        } else if (!strcmp(subkey, ".receivepack")) {
 432                const char *v;
 433                if (git_config_string(&v, key, value))
 434                        return -1;
 435                if (!remote->receivepack)
 436                        remote->receivepack = v;
 437                else
 438                        error("more than one receivepack given, using the first");
 439        } else if (!strcmp(subkey, ".uploadpack")) {
 440                const char *v;
 441                if (git_config_string(&v, key, value))
 442                        return -1;
 443                if (!remote->uploadpack)
 444                        remote->uploadpack = v;
 445                else
 446                        error("more than one uploadpack given, using the first");
 447        } else if (!strcmp(subkey, ".tagopt")) {
 448                if (!strcmp(value, "--no-tags"))
 449                        remote->fetch_tags = -1;
 450                else if (!strcmp(value, "--tags"))
 451                        remote->fetch_tags = 2;
 452        } else if (!strcmp(subkey, ".proxy")) {
 453                return git_config_string((const char **)&remote->http_proxy,
 454                                         key, value);
 455        } else if (!strcmp(subkey, ".vcs")) {
 456                return git_config_string(&remote->foreign_vcs, key, value);
 457        }
 458        return 0;
 459}
 460
 461static void alias_all_urls(void)
 462{
 463        int i, j;
 464        for (i = 0; i < remotes_nr; i++) {
 465                int add_pushurl_aliases;
 466                if (!remotes[i])
 467                        continue;
 468                for (j = 0; j < remotes[i]->pushurl_nr; j++) {
 469                        remotes[i]->pushurl[j] = alias_url(remotes[i]->pushurl[j], &rewrites);
 470                }
 471                add_pushurl_aliases = remotes[i]->pushurl_nr == 0;
 472                for (j = 0; j < remotes[i]->url_nr; j++) {
 473                        if (add_pushurl_aliases)
 474                                add_pushurl_alias(remotes[i], remotes[i]->url[j]);
 475                        remotes[i]->url[j] = alias_url(remotes[i]->url[j], &rewrites);
 476                }
 477        }
 478}
 479
 480static void read_config(void)
 481{
 482        unsigned char sha1[20];
 483        const char *head_ref;
 484        int flag;
 485        if (default_remote_name) /* did this already */
 486                return;
 487        default_remote_name = "origin";
 488        current_branch = NULL;
 489        head_ref = resolve_ref_unsafe("HEAD", sha1, 0, &flag);
 490        if (head_ref && (flag & REF_ISSYMREF) &&
 491            starts_with(head_ref, "refs/heads/")) {
 492                current_branch =
 493                        make_branch(head_ref + strlen("refs/heads/"), 0);
 494        }
 495        git_config(handle_config, NULL);
 496        if (branch_pushremote_name) {
 497                free((char *)pushremote_name);
 498                pushremote_name = branch_pushremote_name;
 499        }
 500        alias_all_urls();
 501}
 502
 503/*
 504 * This function frees a refspec array.
 505 * Warning: code paths should be checked to ensure that the src
 506 *          and dst pointers are always freeable pointers as well
 507 *          as the refspec pointer itself.
 508 */
 509static void free_refspecs(struct refspec *refspec, int nr_refspec)
 510{
 511        int i;
 512
 513        if (!refspec)
 514                return;
 515
 516        for (i = 0; i < nr_refspec; i++) {
 517                free(refspec[i].src);
 518                free(refspec[i].dst);
 519        }
 520        free(refspec);
 521}
 522
 523static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 524{
 525        int i;
 526        struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 527
 528        for (i = 0; i < nr_refspec; i++) {
 529                size_t llen;
 530                int is_glob;
 531                const char *lhs, *rhs;
 532                int flags;
 533
 534                is_glob = 0;
 535
 536                lhs = refspec[i];
 537                if (*lhs == '+') {
 538                        rs[i].force = 1;
 539                        lhs++;
 540                }
 541
 542                rhs = strrchr(lhs, ':');
 543
 544                /*
 545                 * Before going on, special case ":" (or "+:") as a refspec
 546                 * for pushing matching refs.
 547                 */
 548                if (!fetch && rhs == lhs && rhs[1] == '\0') {
 549                        rs[i].matching = 1;
 550                        continue;
 551                }
 552
 553                if (rhs) {
 554                        size_t rlen = strlen(++rhs);
 555                        is_glob = (1 <= rlen && strchr(rhs, '*'));
 556                        rs[i].dst = xstrndup(rhs, rlen);
 557                }
 558
 559                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 560                if (1 <= llen && memchr(lhs, '*', llen)) {
 561                        if ((rhs && !is_glob) || (!rhs && fetch))
 562                                goto invalid;
 563                        is_glob = 1;
 564                } else if (rhs && is_glob) {
 565                        goto invalid;
 566                }
 567
 568                rs[i].pattern = is_glob;
 569                rs[i].src = xstrndup(lhs, llen);
 570                flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 571
 572                if (fetch) {
 573                        unsigned char unused[40];
 574
 575                        /* LHS */
 576                        if (!*rs[i].src)
 577                                ; /* empty is ok; it means "HEAD" */
 578                        else if (llen == 40 && !get_sha1_hex(rs[i].src, unused))
 579                                rs[i].exact_sha1 = 1; /* ok */
 580                        else if (!check_refname_format(rs[i].src, flags))
 581                                ; /* valid looking ref is ok */
 582                        else
 583                                goto invalid;
 584                        /* RHS */
 585                        if (!rs[i].dst)
 586                                ; /* missing is ok; it is the same as empty */
 587                        else if (!*rs[i].dst)
 588                                ; /* empty is ok; it means "do not store" */
 589                        else if (!check_refname_format(rs[i].dst, flags))
 590                                ; /* valid looking ref is ok */
 591                        else
 592                                goto invalid;
 593                } else {
 594                        /*
 595                         * LHS
 596                         * - empty is allowed; it means delete.
 597                         * - when wildcarded, it must be a valid looking ref.
 598                         * - otherwise, it must be an extended SHA-1, but
 599                         *   there is no existing way to validate this.
 600                         */
 601                        if (!*rs[i].src)
 602                                ; /* empty is ok */
 603                        else if (is_glob) {
 604                                if (check_refname_format(rs[i].src, flags))
 605                                        goto invalid;
 606                        }
 607                        else
 608                                ; /* anything goes, for now */
 609                        /*
 610                         * RHS
 611                         * - missing is allowed, but LHS then must be a
 612                         *   valid looking ref.
 613                         * - empty is not allowed.
 614                         * - otherwise it must be a valid looking ref.
 615                         */
 616                        if (!rs[i].dst) {
 617                                if (check_refname_format(rs[i].src, flags))
 618                                        goto invalid;
 619                        } else if (!*rs[i].dst) {
 620                                goto invalid;
 621                        } else {
 622                                if (check_refname_format(rs[i].dst, flags))
 623                                        goto invalid;
 624                        }
 625                }
 626        }
 627        return rs;
 628
 629 invalid:
 630        if (verify) {
 631                /*
 632                 * nr_refspec must be greater than zero and i must be valid
 633                 * since it is only possible to reach this point from within
 634                 * the for loop above.
 635                 */
 636                free_refspecs(rs, i+1);
 637                return NULL;
 638        }
 639        die("Invalid refspec '%s'", refspec[i]);
 640}
 641
 642int valid_fetch_refspec(const char *fetch_refspec_str)
 643{
 644        struct refspec *refspec;
 645
 646        refspec = parse_refspec_internal(1, &fetch_refspec_str, 1, 1);
 647        free_refspecs(refspec, 1);
 648        return !!refspec;
 649}
 650
 651struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 652{
 653        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 654}
 655
 656static struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 657{
 658        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 659}
 660
 661void free_refspec(int nr_refspec, struct refspec *refspec)
 662{
 663        int i;
 664        for (i = 0; i < nr_refspec; i++) {
 665                free(refspec[i].src);
 666                free(refspec[i].dst);
 667        }
 668        free(refspec);
 669}
 670
 671static int valid_remote_nick(const char *name)
 672{
 673        if (!name[0] || is_dot_or_dotdot(name))
 674                return 0;
 675        return !strchr(name, '/'); /* no slash */
 676}
 677
 678static struct remote *remote_get_1(const char *name, const char *pushremote_name)
 679{
 680        struct remote *ret;
 681        int name_given = 0;
 682
 683        if (name)
 684                name_given = 1;
 685        else {
 686                if (pushremote_name) {
 687                        name = pushremote_name;
 688                        name_given = 1;
 689                } else {
 690                        name = default_remote_name;
 691                        name_given = explicit_default_remote_name;
 692                }
 693        }
 694
 695        ret = make_remote(name, 0);
 696        if (valid_remote_nick(name)) {
 697                if (!valid_remote(ret))
 698                        read_remotes_file(ret);
 699                if (!valid_remote(ret))
 700                        read_branches_file(ret);
 701        }
 702        if (name_given && !valid_remote(ret))
 703                add_url_alias(ret, name);
 704        if (!valid_remote(ret))
 705                return NULL;
 706        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 707        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 708        return ret;
 709}
 710
 711struct remote *remote_get(const char *name)
 712{
 713        read_config();
 714        return remote_get_1(name, NULL);
 715}
 716
 717struct remote *pushremote_get(const char *name)
 718{
 719        read_config();
 720        return remote_get_1(name, pushremote_name);
 721}
 722
 723int remote_is_configured(const char *name)
 724{
 725        int i;
 726        read_config();
 727
 728        for (i = 0; i < remotes_nr; i++)
 729                if (!strcmp(name, remotes[i]->name))
 730                        return 1;
 731        return 0;
 732}
 733
 734int for_each_remote(each_remote_fn fn, void *priv)
 735{
 736        int i, result = 0;
 737        read_config();
 738        for (i = 0; i < remotes_nr && !result; i++) {
 739                struct remote *r = remotes[i];
 740                if (!r)
 741                        continue;
 742                if (!r->fetch)
 743                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 744                                                       r->fetch_refspec);
 745                if (!r->push)
 746                        r->push = parse_push_refspec(r->push_refspec_nr,
 747                                                     r->push_refspec);
 748                result = fn(r, priv);
 749        }
 750        return result;
 751}
 752
 753static void handle_duplicate(struct ref *ref1, struct ref *ref2)
 754{
 755        if (strcmp(ref1->name, ref2->name)) {
 756                if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 757                    ref2->fetch_head_status != FETCH_HEAD_IGNORE) {
 758                        die(_("Cannot fetch both %s and %s to %s"),
 759                            ref1->name, ref2->name, ref2->peer_ref->name);
 760                } else if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 761                           ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 762                        warning(_("%s usually tracks %s, not %s"),
 763                                ref2->peer_ref->name, ref2->name, ref1->name);
 764                } else if (ref1->fetch_head_status == FETCH_HEAD_IGNORE &&
 765                           ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 766                        die(_("%s tracks both %s and %s"),
 767                            ref2->peer_ref->name, ref1->name, ref2->name);
 768                } else {
 769                        /*
 770                         * This last possibility doesn't occur because
 771                         * FETCH_HEAD_IGNORE entries always appear at
 772                         * the end of the list.
 773                         */
 774                        die(_("Internal error"));
 775                }
 776        }
 777        free(ref2->peer_ref);
 778        free(ref2);
 779}
 780
 781struct ref *ref_remove_duplicates(struct ref *ref_map)
 782{
 783        struct string_list refs = STRING_LIST_INIT_NODUP;
 784        struct ref *retval = NULL;
 785        struct ref **p = &retval;
 786
 787        while (ref_map) {
 788                struct ref *ref = ref_map;
 789
 790                ref_map = ref_map->next;
 791                ref->next = NULL;
 792
 793                if (!ref->peer_ref) {
 794                        *p = ref;
 795                        p = &ref->next;
 796                } else {
 797                        struct string_list_item *item =
 798                                string_list_insert(&refs, ref->peer_ref->name);
 799
 800                        if (item->util) {
 801                                /* Entry already existed */
 802                                handle_duplicate((struct ref *)item->util, ref);
 803                        } else {
 804                                *p = ref;
 805                                p = &ref->next;
 806                                item->util = ref;
 807                        }
 808                }
 809        }
 810
 811        string_list_clear(&refs, 0);
 812        return retval;
 813}
 814
 815int remote_has_url(struct remote *remote, const char *url)
 816{
 817        int i;
 818        for (i = 0; i < remote->url_nr; i++) {
 819                if (!strcmp(remote->url[i], url))
 820                        return 1;
 821        }
 822        return 0;
 823}
 824
 825static int match_name_with_pattern(const char *key, const char *name,
 826                                   const char *value, char **result)
 827{
 828        const char *kstar = strchr(key, '*');
 829        size_t klen;
 830        size_t ksuffixlen;
 831        size_t namelen;
 832        int ret;
 833        if (!kstar)
 834                die("Key '%s' of pattern had no '*'", key);
 835        klen = kstar - key;
 836        ksuffixlen = strlen(kstar + 1);
 837        namelen = strlen(name);
 838        ret = !strncmp(name, key, klen) && namelen >= klen + ksuffixlen &&
 839                !memcmp(name + namelen - ksuffixlen, kstar + 1, ksuffixlen);
 840        if (ret && value) {
 841                const char *vstar = strchr(value, '*');
 842                size_t vlen;
 843                size_t vsuffixlen;
 844                if (!vstar)
 845                        die("Value '%s' of pattern has no '*'", value);
 846                vlen = vstar - value;
 847                vsuffixlen = strlen(vstar + 1);
 848                *result = xmalloc(vlen + vsuffixlen +
 849                                  strlen(name) -
 850                                  klen - ksuffixlen + 1);
 851                strncpy(*result, value, vlen);
 852                strncpy(*result + vlen,
 853                        name + klen, namelen - klen - ksuffixlen);
 854                strcpy(*result + vlen + namelen - klen - ksuffixlen,
 855                       vstar + 1);
 856        }
 857        return ret;
 858}
 859
 860static void query_refspecs_multiple(struct refspec *refs, int ref_count, struct refspec *query, struct string_list *results)
 861{
 862        int i;
 863        int find_src = !query->src;
 864
 865        if (find_src && !query->dst)
 866                error("query_refspecs_multiple: need either src or dst");
 867
 868        for (i = 0; i < ref_count; i++) {
 869                struct refspec *refspec = &refs[i];
 870                const char *key = find_src ? refspec->dst : refspec->src;
 871                const char *value = find_src ? refspec->src : refspec->dst;
 872                const char *needle = find_src ? query->dst : query->src;
 873                char **result = find_src ? &query->src : &query->dst;
 874
 875                if (!refspec->dst)
 876                        continue;
 877                if (refspec->pattern) {
 878                        if (match_name_with_pattern(key, needle, value, result))
 879                                string_list_append_nodup(results, *result);
 880                } else if (!strcmp(needle, key)) {
 881                        string_list_append(results, value);
 882                }
 883        }
 884}
 885
 886int query_refspecs(struct refspec *refs, int ref_count, struct refspec *query)
 887{
 888        int i;
 889        int find_src = !query->src;
 890        const char *needle = find_src ? query->dst : query->src;
 891        char **result = find_src ? &query->src : &query->dst;
 892
 893        if (find_src && !query->dst)
 894                return error("query_refspecs: need either src or dst");
 895
 896        for (i = 0; i < ref_count; i++) {
 897                struct refspec *refspec = &refs[i];
 898                const char *key = find_src ? refspec->dst : refspec->src;
 899                const char *value = find_src ? refspec->src : refspec->dst;
 900
 901                if (!refspec->dst)
 902                        continue;
 903                if (refspec->pattern) {
 904                        if (match_name_with_pattern(key, needle, value, result)) {
 905                                query->force = refspec->force;
 906                                return 0;
 907                        }
 908                } else if (!strcmp(needle, key)) {
 909                        *result = xstrdup(value);
 910                        query->force = refspec->force;
 911                        return 0;
 912                }
 913        }
 914        return -1;
 915}
 916
 917char *apply_refspecs(struct refspec *refspecs, int nr_refspec,
 918                     const char *name)
 919{
 920        struct refspec query;
 921
 922        memset(&query, 0, sizeof(struct refspec));
 923        query.src = (char *)name;
 924
 925        if (query_refspecs(refspecs, nr_refspec, &query))
 926                return NULL;
 927
 928        return query.dst;
 929}
 930
 931int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 932{
 933        return query_refspecs(remote->fetch, remote->fetch_refspec_nr, refspec);
 934}
 935
 936static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 937                const char *name)
 938{
 939        size_t len = strlen(name);
 940        struct ref *ref = xcalloc(1, sizeof(struct ref) + prefixlen + len + 1);
 941        memcpy(ref->name, prefix, prefixlen);
 942        memcpy(ref->name + prefixlen, name, len);
 943        return ref;
 944}
 945
 946struct ref *alloc_ref(const char *name)
 947{
 948        return alloc_ref_with_prefix("", 0, name);
 949}
 950
 951struct ref *copy_ref(const struct ref *ref)
 952{
 953        struct ref *cpy;
 954        size_t len;
 955        if (!ref)
 956                return NULL;
 957        len = strlen(ref->name);
 958        cpy = xmalloc(sizeof(struct ref) + len + 1);
 959        memcpy(cpy, ref, sizeof(struct ref) + len + 1);
 960        cpy->next = NULL;
 961        cpy->symref = ref->symref ? xstrdup(ref->symref) : NULL;
 962        cpy->remote_status = ref->remote_status ? xstrdup(ref->remote_status) : NULL;
 963        cpy->peer_ref = copy_ref(ref->peer_ref);
 964        return cpy;
 965}
 966
 967struct ref *copy_ref_list(const struct ref *ref)
 968{
 969        struct ref *ret = NULL;
 970        struct ref **tail = &ret;
 971        while (ref) {
 972                *tail = copy_ref(ref);
 973                ref = ref->next;
 974                tail = &((*tail)->next);
 975        }
 976        return ret;
 977}
 978
 979static void free_ref(struct ref *ref)
 980{
 981        if (!ref)
 982                return;
 983        free_ref(ref->peer_ref);
 984        free(ref->remote_status);
 985        free(ref->symref);
 986        free(ref);
 987}
 988
 989void free_refs(struct ref *ref)
 990{
 991        struct ref *next;
 992        while (ref) {
 993                next = ref->next;
 994                free_ref(ref);
 995                ref = next;
 996        }
 997}
 998
 999int ref_compare_name(const void *va, const void *vb)
1000{
1001        const struct ref *a = va, *b = vb;
1002        return strcmp(a->name, b->name);
1003}
1004
1005static void *ref_list_get_next(const void *a)
1006{
1007        return ((const struct ref *)a)->next;
1008}
1009
1010static void ref_list_set_next(void *a, void *next)
1011{
1012        ((struct ref *)a)->next = next;
1013}
1014
1015void sort_ref_list(struct ref **l, int (*cmp)(const void *, const void *))
1016{
1017        *l = llist_mergesort(*l, ref_list_get_next, ref_list_set_next, cmp);
1018}
1019
1020int count_refspec_match(const char *pattern,
1021                        struct ref *refs,
1022                        struct ref **matched_ref)
1023{
1024        int patlen = strlen(pattern);
1025        struct ref *matched_weak = NULL;
1026        struct ref *matched = NULL;
1027        int weak_match = 0;
1028        int match = 0;
1029
1030        for (weak_match = match = 0; refs; refs = refs->next) {
1031                char *name = refs->name;
1032                int namelen = strlen(name);
1033
1034                if (!refname_match(pattern, name))
1035                        continue;
1036
1037                /* A match is "weak" if it is with refs outside
1038                 * heads or tags, and did not specify the pattern
1039                 * in full (e.g. "refs/remotes/origin/master") or at
1040                 * least from the toplevel (e.g. "remotes/origin/master");
1041                 * otherwise "git push $URL master" would result in
1042                 * ambiguity between remotes/origin/master and heads/master
1043                 * at the remote site.
1044                 */
1045                if (namelen != patlen &&
1046                    patlen != namelen - 5 &&
1047                    !starts_with(name, "refs/heads/") &&
1048                    !starts_with(name, "refs/tags/")) {
1049                        /* We want to catch the case where only weak
1050                         * matches are found and there are multiple
1051                         * matches, and where more than one strong
1052                         * matches are found, as ambiguous.  One
1053                         * strong match with zero or more weak matches
1054                         * are acceptable as a unique match.
1055                         */
1056                        matched_weak = refs;
1057                        weak_match++;
1058                }
1059                else {
1060                        matched = refs;
1061                        match++;
1062                }
1063        }
1064        if (!matched) {
1065                *matched_ref = matched_weak;
1066                return weak_match;
1067        }
1068        else {
1069                *matched_ref = matched;
1070                return match;
1071        }
1072}
1073
1074static void tail_link_ref(struct ref *ref, struct ref ***tail)
1075{
1076        **tail = ref;
1077        while (ref->next)
1078                ref = ref->next;
1079        *tail = &ref->next;
1080}
1081
1082static struct ref *alloc_delete_ref(void)
1083{
1084        struct ref *ref = alloc_ref("(delete)");
1085        hashclr(ref->new_sha1);
1086        return ref;
1087}
1088
1089static struct ref *try_explicit_object_name(const char *name)
1090{
1091        unsigned char sha1[20];
1092        struct ref *ref;
1093
1094        if (!*name)
1095                return alloc_delete_ref();
1096        if (get_sha1(name, sha1))
1097                return NULL;
1098        ref = alloc_ref(name);
1099        hashcpy(ref->new_sha1, sha1);
1100        return ref;
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, sha1, 1, NULL);
1116        if (!r)
1117                return NULL;
1118
1119        if (starts_with(r, "refs/heads/"))
1120                strbuf_addstr(&buf, "refs/heads/");
1121        else if (starts_with(r, "refs/tags/"))
1122                strbuf_addstr(&buf, "refs/tags/");
1123        else
1124                return NULL;
1125
1126        strbuf_addstr(&buf, name);
1127        return strbuf_detach(&buf, NULL);
1128}
1129
1130static int match_explicit(struct ref *src, struct ref *dst,
1131                          struct ref ***dst_tail,
1132                          struct refspec *rs)
1133{
1134        struct ref *matched_src, *matched_dst;
1135        int copy_src;
1136
1137        const char *dst_value = rs->dst;
1138        char *dst_guess;
1139
1140        if (rs->pattern || rs->matching)
1141                return 0;
1142
1143        matched_src = matched_dst = NULL;
1144        switch (count_refspec_match(rs->src, src, &matched_src)) {
1145        case 1:
1146                copy_src = 1;
1147                break;
1148        case 0:
1149                /* The source could be in the get_sha1() format
1150                 * not a reference name.  :refs/other is a
1151                 * way to delete 'other' ref at the remote end.
1152                 */
1153                matched_src = try_explicit_object_name(rs->src);
1154                if (!matched_src)
1155                        return error("src refspec %s does not match any.", rs->src);
1156                copy_src = 0;
1157                break;
1158        default:
1159                return error("src refspec %s matches more than one.", rs->src);
1160        }
1161
1162        if (!dst_value) {
1163                unsigned char sha1[20];
1164                int flag;
1165
1166                dst_value = resolve_ref_unsafe(matched_src->name, sha1, 1, &flag);
1167                if (!dst_value ||
1168                    ((flag & REF_ISSYMREF) &&
1169                     !starts_with(dst_value, "refs/heads/")))
1170                        die("%s cannot be resolved to branch.",
1171                            matched_src->name);
1172        }
1173
1174        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
1175        case 1:
1176                break;
1177        case 0:
1178                if (!memcmp(dst_value, "refs/", 5))
1179                        matched_dst = make_linked_ref(dst_value, dst_tail);
1180                else if (is_null_sha1(matched_src->new_sha1))
1181                        error("unable to delete '%s': remote ref does not exist",
1182                              dst_value);
1183                else if ((dst_guess = guess_ref(dst_value, matched_src)))
1184                        matched_dst = make_linked_ref(dst_guess, dst_tail);
1185                else
1186                        error("unable to push to unqualified destination: %s\n"
1187                              "The destination refspec neither matches an "
1188                              "existing ref on the remote nor\n"
1189                              "begins with refs/, and we are unable to "
1190                              "guess a prefix based on the source ref.",
1191                              dst_value);
1192                break;
1193        default:
1194                matched_dst = NULL;
1195                error("dst refspec %s matches more than one.",
1196                      dst_value);
1197                break;
1198        }
1199        if (!matched_dst)
1200                return -1;
1201        if (matched_dst->peer_ref)
1202                return error("dst ref %s receives from more than one src.",
1203                      matched_dst->name);
1204        else {
1205                matched_dst->peer_ref = copy_src ? copy_ref(matched_src) : matched_src;
1206                matched_dst->force = rs->force;
1207        }
1208        return 0;
1209}
1210
1211static int match_explicit_refs(struct ref *src, struct ref *dst,
1212                               struct ref ***dst_tail, struct refspec *rs,
1213                               int rs_nr)
1214{
1215        int i, errs;
1216        for (i = errs = 0; i < rs_nr; i++)
1217                errs += match_explicit(src, dst, dst_tail, &rs[i]);
1218        return errs;
1219}
1220
1221static char *get_ref_match(const struct refspec *rs, int rs_nr, const struct ref *ref,
1222                int send_mirror, int direction, const struct refspec **ret_pat)
1223{
1224        const struct refspec *pat;
1225        char *name;
1226        int i;
1227        int matching_refs = -1;
1228        for (i = 0; i < rs_nr; i++) {
1229                if (rs[i].matching &&
1230                    (matching_refs == -1 || rs[i].force)) {
1231                        matching_refs = i;
1232                        continue;
1233                }
1234
1235                if (rs[i].pattern) {
1236                        const char *dst_side = rs[i].dst ? rs[i].dst : rs[i].src;
1237                        int match;
1238                        if (direction == FROM_SRC)
1239                                match = match_name_with_pattern(rs[i].src, ref->name, dst_side, &name);
1240                        else
1241                                match = match_name_with_pattern(dst_side, ref->name, rs[i].src, &name);
1242                        if (match) {
1243                                matching_refs = i;
1244                                break;
1245                        }
1246                }
1247        }
1248        if (matching_refs == -1)
1249                return NULL;
1250
1251        pat = rs + matching_refs;
1252        if (pat->matching) {
1253                /*
1254                 * "matching refs"; traditionally we pushed everything
1255                 * including refs outside refs/heads/ hierarchy, but
1256                 * that does not make much sense these days.
1257                 */
1258                if (!send_mirror && !starts_with(ref->name, "refs/heads/"))
1259                        return NULL;
1260                name = xstrdup(ref->name);
1261        }
1262        if (ret_pat)
1263                *ret_pat = pat;
1264        return name;
1265}
1266
1267static struct ref **tail_ref(struct ref **head)
1268{
1269        struct ref **tail = head;
1270        while (*tail)
1271                tail = &((*tail)->next);
1272        return tail;
1273}
1274
1275struct tips {
1276        struct commit **tip;
1277        int nr, alloc;
1278};
1279
1280static void add_to_tips(struct tips *tips, const unsigned char *sha1)
1281{
1282        struct commit *commit;
1283
1284        if (is_null_sha1(sha1))
1285                return;
1286        commit = lookup_commit_reference_gently(sha1, 1);
1287        if (!commit || (commit->object.flags & TMP_MARK))
1288                return;
1289        commit->object.flags |= TMP_MARK;
1290        ALLOC_GROW(tips->tip, tips->nr + 1, tips->alloc);
1291        tips->tip[tips->nr++] = commit;
1292}
1293
1294static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***dst_tail)
1295{
1296        struct string_list dst_tag = STRING_LIST_INIT_NODUP;
1297        struct string_list src_tag = STRING_LIST_INIT_NODUP;
1298        struct string_list_item *item;
1299        struct ref *ref;
1300        struct tips sent_tips;
1301
1302        /*
1303         * Collect everything we know they would have at the end of
1304         * this push, and collect all tags they have.
1305         */
1306        memset(&sent_tips, 0, sizeof(sent_tips));
1307        for (ref = *dst; ref; ref = ref->next) {
1308                if (ref->peer_ref &&
1309                    !is_null_sha1(ref->peer_ref->new_sha1))
1310                        add_to_tips(&sent_tips, ref->peer_ref->new_sha1);
1311                else
1312                        add_to_tips(&sent_tips, ref->old_sha1);
1313                if (starts_with(ref->name, "refs/tags/"))
1314                        string_list_append(&dst_tag, ref->name);
1315        }
1316        clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
1317
1318        sort_string_list(&dst_tag);
1319
1320        /* Collect tags they do not have. */
1321        for (ref = src; ref; ref = ref->next) {
1322                if (!starts_with(ref->name, "refs/tags/"))
1323                        continue; /* not a tag */
1324                if (string_list_has_string(&dst_tag, ref->name))
1325                        continue; /* they already have it */
1326                if (sha1_object_info(ref->new_sha1, NULL) != OBJ_TAG)
1327                        continue; /* be conservative */
1328                item = string_list_append(&src_tag, ref->name);
1329                item->util = ref;
1330        }
1331        string_list_clear(&dst_tag, 0);
1332
1333        /*
1334         * At this point, src_tag lists tags that are missing from
1335         * dst, and sent_tips lists the tips we are pushing or those
1336         * that we know they already have. An element in the src_tag
1337         * that is an ancestor of any of the sent_tips needs to be
1338         * sent to the other side.
1339         */
1340        if (sent_tips.nr) {
1341                for_each_string_list_item(item, &src_tag) {
1342                        struct ref *ref = item->util;
1343                        struct ref *dst_ref;
1344                        struct commit *commit;
1345
1346                        if (is_null_sha1(ref->new_sha1))
1347                                continue;
1348                        commit = lookup_commit_reference_gently(ref->new_sha1, 1);
1349                        if (!commit)
1350                                /* not pushing a commit, which is not an error */
1351                                continue;
1352
1353                        /*
1354                         * Is this tag, which they do not have, reachable from
1355                         * any of the commits we are sending?
1356                         */
1357                        if (!in_merge_bases_many(commit, sent_tips.nr, sent_tips.tip))
1358                                continue;
1359
1360                        /* Add it in */
1361                        dst_ref = make_linked_ref(ref->name, dst_tail);
1362                        hashcpy(dst_ref->new_sha1, ref->new_sha1);
1363                        dst_ref->peer_ref = copy_ref(ref);
1364                }
1365        }
1366        string_list_clear(&src_tag, 0);
1367        free(sent_tips.tip);
1368}
1369
1370struct ref *find_ref_by_name(const struct ref *list, const char *name)
1371{
1372        for ( ; list; list = list->next)
1373                if (!strcmp(list->name, name))
1374                        return (struct ref *)list;
1375        return NULL;
1376}
1377
1378static void prepare_ref_index(struct string_list *ref_index, struct ref *ref)
1379{
1380        for ( ; ref; ref = ref->next)
1381                string_list_append_nodup(ref_index, ref->name)->util = ref;
1382
1383        sort_string_list(ref_index);
1384}
1385
1386/*
1387 * Given the set of refs the local repository has, the set of refs the
1388 * remote repository has, and the refspec used for push, determine
1389 * what remote refs we will update and with what value by setting
1390 * peer_ref (which object is being pushed) and force (if the push is
1391 * forced) in elements of "dst". The function may add new elements to
1392 * dst (e.g. pushing to a new branch, done in match_explicit_refs).
1393 */
1394int match_push_refs(struct ref *src, struct ref **dst,
1395                    int nr_refspec, const char **refspec, int flags)
1396{
1397        struct refspec *rs;
1398        int send_all = flags & MATCH_REFS_ALL;
1399        int send_mirror = flags & MATCH_REFS_MIRROR;
1400        int send_prune = flags & MATCH_REFS_PRUNE;
1401        int errs;
1402        static const char *default_refspec[] = { ":", NULL };
1403        struct ref *ref, **dst_tail = tail_ref(dst);
1404        struct string_list dst_ref_index = STRING_LIST_INIT_NODUP;
1405
1406        if (!nr_refspec) {
1407                nr_refspec = 1;
1408                refspec = default_refspec;
1409        }
1410        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1411        errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
1412
1413        /* pick the remainder */
1414        for (ref = src; ref; ref = ref->next) {
1415                struct string_list_item *dst_item;
1416                struct ref *dst_peer;
1417                const struct refspec *pat = NULL;
1418                char *dst_name;
1419
1420                dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
1421                if (!dst_name)
1422                        continue;
1423
1424                if (!dst_ref_index.nr)
1425                        prepare_ref_index(&dst_ref_index, *dst);
1426
1427                dst_item = string_list_lookup(&dst_ref_index, dst_name);
1428                dst_peer = dst_item ? dst_item->util : NULL;
1429                if (dst_peer) {
1430                        if (dst_peer->peer_ref)
1431                                /* We're already sending something to this ref. */
1432                                goto free_name;
1433                } else {
1434                        if (pat->matching && !(send_all || send_mirror))
1435                                /*
1436                                 * Remote doesn't have it, and we have no
1437                                 * explicit pattern, and we don't have
1438                                 * --all or --mirror.
1439                                 */
1440                                goto free_name;
1441
1442                        /* Create a new one and link it */
1443                        dst_peer = make_linked_ref(dst_name, &dst_tail);
1444                        hashcpy(dst_peer->new_sha1, ref->new_sha1);
1445                        string_list_insert(&dst_ref_index,
1446                                dst_peer->name)->util = dst_peer;
1447                }
1448                dst_peer->peer_ref = copy_ref(ref);
1449                dst_peer->force = pat->force;
1450        free_name:
1451                free(dst_name);
1452        }
1453
1454        string_list_clear(&dst_ref_index, 0);
1455
1456        if (flags & MATCH_REFS_FOLLOW_TAGS)
1457                add_missing_tags(src, dst, &dst_tail);
1458
1459        if (send_prune) {
1460                struct string_list src_ref_index = STRING_LIST_INIT_NODUP;
1461                /* check for missing refs on the remote */
1462                for (ref = *dst; ref; ref = ref->next) {
1463                        char *src_name;
1464
1465                        if (ref->peer_ref)
1466                                /* We're already sending something to this ref. */
1467                                continue;
1468
1469                        src_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_DST, NULL);
1470                        if (src_name) {
1471                                if (!src_ref_index.nr)
1472                                        prepare_ref_index(&src_ref_index, src);
1473                                if (!string_list_has_string(&src_ref_index,
1474                                            src_name))
1475                                        ref->peer_ref = alloc_delete_ref();
1476                                free(src_name);
1477                        }
1478                }
1479                string_list_clear(&src_ref_index, 0);
1480        }
1481        if (errs)
1482                return -1;
1483        return 0;
1484}
1485
1486void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
1487                             int force_update)
1488{
1489        struct ref *ref;
1490
1491        for (ref = remote_refs; ref; ref = ref->next) {
1492                int force_ref_update = ref->force || force_update;
1493                int reject_reason = 0;
1494
1495                if (ref->peer_ref)
1496                        hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
1497                else if (!send_mirror)
1498                        continue;
1499
1500                ref->deletion = is_null_sha1(ref->new_sha1);
1501                if (!ref->deletion &&
1502                        !hashcmp(ref->old_sha1, ref->new_sha1)) {
1503                        ref->status = REF_STATUS_UPTODATE;
1504                        continue;
1505                }
1506
1507                /*
1508                 * Bypass the usual "must fast-forward" check but
1509                 * replace it with a weaker "the old value must be
1510                 * this value we observed".  If the remote ref has
1511                 * moved and is now different from what we expect,
1512                 * reject any push.
1513                 *
1514                 * It also is an error if the user told us to check
1515                 * with the remote-tracking branch to find the value
1516                 * to expect, but we did not have such a tracking
1517                 * branch.
1518                 */
1519                if (ref->expect_old_sha1) {
1520                        if (ref->expect_old_no_trackback ||
1521                            hashcmp(ref->old_sha1, ref->old_sha1_expect))
1522                                reject_reason = REF_STATUS_REJECT_STALE;
1523                }
1524
1525                /*
1526                 * The usual "must fast-forward" rules.
1527                 *
1528                 * Decide whether an individual refspec A:B can be
1529                 * pushed.  The push will succeed if any of the
1530                 * following are true:
1531                 *
1532                 * (1) the remote reference B does not exist
1533                 *
1534                 * (2) the remote reference B is being removed (i.e.,
1535                 *     pushing :B where no source is specified)
1536                 *
1537                 * (3) the destination is not under refs/tags/, and
1538                 *     if the old and new value is a commit, the new
1539                 *     is a descendant of the old.
1540                 *
1541                 * (4) it is forced using the +A:B notation, or by
1542                 *     passing the --force argument
1543                 */
1544
1545                else if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
1546                        if (starts_with(ref->name, "refs/tags/"))
1547                                reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
1548                        else if (!has_sha1_file(ref->old_sha1))
1549                                reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
1550                        else if (!lookup_commit_reference_gently(ref->old_sha1, 1) ||
1551                                 !lookup_commit_reference_gently(ref->new_sha1, 1))
1552                                reject_reason = REF_STATUS_REJECT_NEEDS_FORCE;
1553                        else if (!ref_newer(ref->new_sha1, ref->old_sha1))
1554                                reject_reason = REF_STATUS_REJECT_NONFASTFORWARD;
1555                }
1556
1557                /*
1558                 * "--force" will defeat any rejection implemented
1559                 * by the rules above.
1560                 */
1561                if (!force_ref_update)
1562                        ref->status = reject_reason;
1563                else if (reject_reason)
1564                        ref->forced_update = 1;
1565        }
1566}
1567
1568struct branch *branch_get(const char *name)
1569{
1570        struct branch *ret;
1571
1572        read_config();
1573        if (!name || !*name || !strcmp(name, "HEAD"))
1574                ret = current_branch;
1575        else
1576                ret = make_branch(name, 0);
1577        if (ret && ret->remote_name) {
1578                ret->remote = remote_get(ret->remote_name);
1579                if (ret->merge_nr) {
1580                        int i;
1581                        ret->merge = xcalloc(ret->merge_nr, sizeof(*ret->merge));
1582                        for (i = 0; i < ret->merge_nr; i++) {
1583                                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1584                                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1585                                if (remote_find_tracking(ret->remote, ret->merge[i])
1586                                    && !strcmp(ret->remote_name, "."))
1587                                        ret->merge[i]->dst = xstrdup(ret->merge_name[i]);
1588                        }
1589                }
1590        }
1591        return ret;
1592}
1593
1594int branch_has_merge_config(struct branch *branch)
1595{
1596        return branch && !!branch->merge;
1597}
1598
1599int branch_merge_matches(struct branch *branch,
1600                                 int i,
1601                                 const char *refname)
1602{
1603        if (!branch || i < 0 || i >= branch->merge_nr)
1604                return 0;
1605        return refname_match(branch->merge[i]->src, refname);
1606}
1607
1608static int ignore_symref_update(const char *refname)
1609{
1610        unsigned char sha1[20];
1611        int flag;
1612
1613        if (!resolve_ref_unsafe(refname, sha1, 0, &flag))
1614                return 0; /* non-existing refs are OK */
1615        return (flag & REF_ISSYMREF);
1616}
1617
1618/*
1619 * Create and return a list of (struct ref) consisting of copies of
1620 * each remote_ref that matches refspec.  refspec must be a pattern.
1621 * Fill in the copies' peer_ref to describe the local tracking refs to
1622 * which they map.  Omit any references that would map to an existing
1623 * local symbolic ref.
1624 */
1625static struct ref *get_expanded_map(const struct ref *remote_refs,
1626                                    const struct refspec *refspec)
1627{
1628        const struct ref *ref;
1629        struct ref *ret = NULL;
1630        struct ref **tail = &ret;
1631
1632        for (ref = remote_refs; ref; ref = ref->next) {
1633                char *expn_name = NULL;
1634
1635                if (strchr(ref->name, '^'))
1636                        continue; /* a dereference item */
1637                if (match_name_with_pattern(refspec->src, ref->name,
1638                                            refspec->dst, &expn_name) &&
1639                    !ignore_symref_update(expn_name)) {
1640                        struct ref *cpy = copy_ref(ref);
1641
1642                        cpy->peer_ref = alloc_ref(expn_name);
1643                        if (refspec->force)
1644                                cpy->peer_ref->force = 1;
1645                        *tail = cpy;
1646                        tail = &cpy->next;
1647                }
1648                free(expn_name);
1649        }
1650
1651        return ret;
1652}
1653
1654static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1655{
1656        const struct ref *ref;
1657        for (ref = refs; ref; ref = ref->next) {
1658                if (refname_match(name, ref->name))
1659                        return ref;
1660        }
1661        return NULL;
1662}
1663
1664struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1665{
1666        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1667
1668        if (!ref)
1669                return NULL;
1670
1671        return copy_ref(ref);
1672}
1673
1674static struct ref *get_local_ref(const char *name)
1675{
1676        if (!name || name[0] == '\0')
1677                return NULL;
1678
1679        if (starts_with(name, "refs/"))
1680                return alloc_ref(name);
1681
1682        if (starts_with(name, "heads/") ||
1683            starts_with(name, "tags/") ||
1684            starts_with(name, "remotes/"))
1685                return alloc_ref_with_prefix("refs/", 5, name);
1686
1687        return alloc_ref_with_prefix("refs/heads/", 11, name);
1688}
1689
1690int get_fetch_map(const struct ref *remote_refs,
1691                  const struct refspec *refspec,
1692                  struct ref ***tail,
1693                  int missing_ok)
1694{
1695        struct ref *ref_map, **rmp;
1696
1697        if (refspec->pattern) {
1698                ref_map = get_expanded_map(remote_refs, refspec);
1699        } else {
1700                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1701
1702                if (refspec->exact_sha1) {
1703                        ref_map = alloc_ref(name);
1704                        get_sha1_hex(name, ref_map->old_sha1);
1705                } else {
1706                        ref_map = get_remote_ref(remote_refs, name);
1707                }
1708                if (!missing_ok && !ref_map)
1709                        die("Couldn't find remote ref %s", name);
1710                if (ref_map) {
1711                        ref_map->peer_ref = get_local_ref(refspec->dst);
1712                        if (ref_map->peer_ref && refspec->force)
1713                                ref_map->peer_ref->force = 1;
1714                }
1715        }
1716
1717        for (rmp = &ref_map; *rmp; ) {
1718                if ((*rmp)->peer_ref) {
1719                        if (!starts_with((*rmp)->peer_ref->name, "refs/") ||
1720                            check_refname_format((*rmp)->peer_ref->name, 0)) {
1721                                struct ref *ignore = *rmp;
1722                                error("* Ignoring funny ref '%s' locally",
1723                                      (*rmp)->peer_ref->name);
1724                                *rmp = (*rmp)->next;
1725                                free(ignore->peer_ref);
1726                                free(ignore);
1727                                continue;
1728                        }
1729                }
1730                rmp = &((*rmp)->next);
1731        }
1732
1733        if (ref_map)
1734                tail_link_ref(ref_map, tail);
1735
1736        return 0;
1737}
1738
1739int resolve_remote_symref(struct ref *ref, struct ref *list)
1740{
1741        if (!ref->symref)
1742                return 0;
1743        for (; list; list = list->next)
1744                if (!strcmp(ref->symref, list->name)) {
1745                        hashcpy(ref->old_sha1, list->old_sha1);
1746                        return 0;
1747                }
1748        return 1;
1749}
1750
1751static void unmark_and_free(struct commit_list *list, unsigned int mark)
1752{
1753        while (list) {
1754                struct commit_list *temp = list;
1755                temp->item->object.flags &= ~mark;
1756                list = temp->next;
1757                free(temp);
1758        }
1759}
1760
1761int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
1762{
1763        struct object *o;
1764        struct commit *old, *new;
1765        struct commit_list *list, *used;
1766        int found = 0;
1767
1768        /*
1769         * Both new and old must be commit-ish and new is descendant of
1770         * old.  Otherwise we require --force.
1771         */
1772        o = deref_tag(parse_object(old_sha1), NULL, 0);
1773        if (!o || o->type != OBJ_COMMIT)
1774                return 0;
1775        old = (struct commit *) o;
1776
1777        o = deref_tag(parse_object(new_sha1), NULL, 0);
1778        if (!o || o->type != OBJ_COMMIT)
1779                return 0;
1780        new = (struct commit *) o;
1781
1782        if (parse_commit(new) < 0)
1783                return 0;
1784
1785        used = list = NULL;
1786        commit_list_insert(new, &list);
1787        while (list) {
1788                new = pop_most_recent_commit(&list, TMP_MARK);
1789                commit_list_insert(new, &used);
1790                if (new == old) {
1791                        found = 1;
1792                        break;
1793                }
1794        }
1795        unmark_and_free(list, TMP_MARK);
1796        unmark_and_free(used, TMP_MARK);
1797        return found;
1798}
1799
1800/*
1801 * Compare a branch with its upstream, and save their differences (number
1802 * of commits) in *num_ours and *num_theirs.
1803 *
1804 * Return 0 if branch has no upstream (no base), -1 if upstream is missing
1805 * (with "gone" base), otherwise 1 (with base).
1806 */
1807int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
1808{
1809        unsigned char sha1[20];
1810        struct commit *ours, *theirs;
1811        char symmetric[84];
1812        struct rev_info revs;
1813        const char *rev_argv[10], *base;
1814        int rev_argc;
1815
1816        /* Cannot stat unless we are marked to build on top of somebody else. */
1817        if (!branch ||
1818            !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
1819                return 0;
1820
1821        /* Cannot stat if what we used to build on no longer exists */
1822        base = branch->merge[0]->dst;
1823        if (read_ref(base, sha1))
1824                return -1;
1825        theirs = lookup_commit_reference(sha1);
1826        if (!theirs)
1827                return -1;
1828
1829        if (read_ref(branch->refname, sha1))
1830                return -1;
1831        ours = lookup_commit_reference(sha1);
1832        if (!ours)
1833                return -1;
1834
1835        /* are we the same? */
1836        if (theirs == ours) {
1837                *num_theirs = *num_ours = 0;
1838                return 1;
1839        }
1840
1841        /* Run "rev-list --left-right ours...theirs" internally... */
1842        rev_argc = 0;
1843        rev_argv[rev_argc++] = NULL;
1844        rev_argv[rev_argc++] = "--left-right";
1845        rev_argv[rev_argc++] = symmetric;
1846        rev_argv[rev_argc++] = "--";
1847        rev_argv[rev_argc] = NULL;
1848
1849        strcpy(symmetric, sha1_to_hex(ours->object.sha1));
1850        strcpy(symmetric + 40, "...");
1851        strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
1852
1853        init_revisions(&revs, NULL);
1854        setup_revisions(rev_argc, rev_argv, &revs, NULL);
1855        prepare_revision_walk(&revs);
1856
1857        /* ... and count the commits on each side. */
1858        *num_ours = 0;
1859        *num_theirs = 0;
1860        while (1) {
1861                struct commit *c = get_revision(&revs);
1862                if (!c)
1863                        break;
1864                if (c->object.flags & SYMMETRIC_LEFT)
1865                        (*num_ours)++;
1866                else
1867                        (*num_theirs)++;
1868        }
1869
1870        /* clear object flags smudged by the above traversal */
1871        clear_commit_marks(ours, ALL_REV_FLAGS);
1872        clear_commit_marks(theirs, ALL_REV_FLAGS);
1873        return 1;
1874}
1875
1876/*
1877 * Return true when there is anything to report, otherwise false.
1878 */
1879int format_tracking_info(struct branch *branch, struct strbuf *sb)
1880{
1881        int ours, theirs;
1882        const char *base;
1883        int upstream_is_gone = 0;
1884
1885        switch (stat_tracking_info(branch, &ours, &theirs)) {
1886        case 0:
1887                /* no base */
1888                return 0;
1889        case -1:
1890                /* with "gone" base */
1891                upstream_is_gone = 1;
1892                break;
1893        default:
1894                /* with base */
1895                break;
1896        }
1897
1898        base = branch->merge[0]->dst;
1899        base = shorten_unambiguous_ref(base, 0);
1900        if (upstream_is_gone) {
1901                strbuf_addf(sb,
1902                        _("Your branch is based on '%s', but the upstream is gone.\n"),
1903                        base);
1904                if (advice_status_hints)
1905                        strbuf_addf(sb,
1906                                _("  (use \"git branch --unset-upstream\" to fixup)\n"));
1907        } else if (!ours && !theirs) {
1908                strbuf_addf(sb,
1909                        _("Your branch is up-to-date with '%s'.\n"),
1910                        base);
1911        } else if (!theirs) {
1912                strbuf_addf(sb,
1913                        Q_("Your branch is ahead of '%s' by %d commit.\n",
1914                           "Your branch is ahead of '%s' by %d commits.\n",
1915                           ours),
1916                        base, ours);
1917                if (advice_status_hints)
1918                        strbuf_addf(sb,
1919                                _("  (use \"git push\" to publish your local commits)\n"));
1920        } else if (!ours) {
1921                strbuf_addf(sb,
1922                        Q_("Your branch is behind '%s' by %d commit, "
1923                               "and can be fast-forwarded.\n",
1924                           "Your branch is behind '%s' by %d commits, "
1925                               "and can be fast-forwarded.\n",
1926                           theirs),
1927                        base, theirs);
1928                if (advice_status_hints)
1929                        strbuf_addf(sb,
1930                                _("  (use \"git pull\" to update your local branch)\n"));
1931        } else {
1932                strbuf_addf(sb,
1933                        Q_("Your branch and '%s' have diverged,\n"
1934                               "and have %d and %d different commit each, "
1935                               "respectively.\n",
1936                           "Your branch and '%s' have diverged,\n"
1937                               "and have %d and %d different commits each, "
1938                               "respectively.\n",
1939                           theirs),
1940                        base, ours, theirs);
1941                if (advice_status_hints)
1942                        strbuf_addf(sb,
1943                                _("  (use \"git pull\" to merge the remote branch into yours)\n"));
1944        }
1945        return 1;
1946}
1947
1948static int one_local_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
1949{
1950        struct ref ***local_tail = cb_data;
1951        struct ref *ref;
1952        int len;
1953
1954        /* we already know it starts with refs/ to get here */
1955        if (check_refname_format(refname + 5, 0))
1956                return 0;
1957
1958        len = strlen(refname) + 1;
1959        ref = xcalloc(1, sizeof(*ref) + len);
1960        hashcpy(ref->new_sha1, sha1);
1961        memcpy(ref->name, refname, len);
1962        **local_tail = ref;
1963        *local_tail = &ref->next;
1964        return 0;
1965}
1966
1967struct ref *get_local_heads(void)
1968{
1969        struct ref *local_refs = NULL, **local_tail = &local_refs;
1970        for_each_ref(one_local_ref, &local_tail);
1971        return local_refs;
1972}
1973
1974struct ref *guess_remote_head(const struct ref *head,
1975                              const struct ref *refs,
1976                              int all)
1977{
1978        const struct ref *r;
1979        struct ref *list = NULL;
1980        struct ref **tail = &list;
1981
1982        if (!head)
1983                return NULL;
1984
1985        /*
1986         * Some transports support directly peeking at
1987         * where HEAD points; if that is the case, then
1988         * we don't have to guess.
1989         */
1990        if (head->symref)
1991                return copy_ref(find_ref_by_name(refs, head->symref));
1992
1993        /* If refs/heads/master could be right, it is. */
1994        if (!all) {
1995                r = find_ref_by_name(refs, "refs/heads/master");
1996                if (r && !hashcmp(r->old_sha1, head->old_sha1))
1997                        return copy_ref(r);
1998        }
1999
2000        /* Look for another ref that points there */
2001        for (r = refs; r; r = r->next) {
2002                if (r != head &&
2003                    starts_with(r->name, "refs/heads/") &&
2004                    !hashcmp(r->old_sha1, head->old_sha1)) {
2005                        *tail = copy_ref(r);
2006                        tail = &((*tail)->next);
2007                        if (!all)
2008                                break;
2009                }
2010        }
2011
2012        return list;
2013}
2014
2015struct stale_heads_info {
2016        struct string_list *ref_names;
2017        struct ref **stale_refs_tail;
2018        struct refspec *refs;
2019        int ref_count;
2020};
2021
2022static int get_stale_heads_cb(const char *refname,
2023        const unsigned char *sha1, int flags, void *cb_data)
2024{
2025        struct stale_heads_info *info = cb_data;
2026        struct string_list matches = STRING_LIST_INIT_DUP;
2027        struct refspec query;
2028        int i, stale = 1;
2029        memset(&query, 0, sizeof(struct refspec));
2030        query.dst = (char *)refname;
2031
2032        query_refspecs_multiple(info->refs, info->ref_count, &query, &matches);
2033        if (matches.nr == 0)
2034                goto clean_exit; /* No matches */
2035
2036        /*
2037         * If we did find a suitable refspec and it's not a symref and
2038         * it's not in the list of refs that currently exist in that
2039         * remote, we consider it to be stale. In order to deal with
2040         * overlapping refspecs, we need to go over all of the
2041         * matching refs.
2042         */
2043        if (flags & REF_ISSYMREF)
2044                goto clean_exit;
2045
2046        for (i = 0; stale && i < matches.nr; i++)
2047                if (string_list_has_string(info->ref_names, matches.items[i].string))
2048                        stale = 0;
2049
2050        if (stale) {
2051                struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
2052                hashcpy(ref->new_sha1, sha1);
2053        }
2054
2055clean_exit:
2056        string_list_clear(&matches, 0);
2057        return 0;
2058}
2059
2060struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fetch_map)
2061{
2062        struct ref *ref, *stale_refs = NULL;
2063        struct string_list ref_names = STRING_LIST_INIT_NODUP;
2064        struct stale_heads_info info;
2065        info.ref_names = &ref_names;
2066        info.stale_refs_tail = &stale_refs;
2067        info.refs = refs;
2068        info.ref_count = ref_count;
2069        for (ref = fetch_map; ref; ref = ref->next)
2070                string_list_append(&ref_names, ref->name);
2071        sort_string_list(&ref_names);
2072        for_each_ref(get_stale_heads_cb, &info);
2073        string_list_clear(&ref_names, 0);
2074        return stale_refs;
2075}
2076
2077/*
2078 * Compare-and-swap
2079 */
2080void clear_cas_option(struct push_cas_option *cas)
2081{
2082        int i;
2083
2084        for (i = 0; i < cas->nr; i++)
2085                free(cas->entry[i].refname);
2086        free(cas->entry);
2087        memset(cas, 0, sizeof(*cas));
2088}
2089
2090static struct push_cas *add_cas_entry(struct push_cas_option *cas,
2091                                      const char *refname,
2092                                      size_t refnamelen)
2093{
2094        struct push_cas *entry;
2095        ALLOC_GROW(cas->entry, cas->nr + 1, cas->alloc);
2096        entry = &cas->entry[cas->nr++];
2097        memset(entry, 0, sizeof(*entry));
2098        entry->refname = xmemdupz(refname, refnamelen);
2099        return entry;
2100}
2101
2102int parse_push_cas_option(struct push_cas_option *cas, const char *arg, int unset)
2103{
2104        const char *colon;
2105        struct push_cas *entry;
2106
2107        if (unset) {
2108                /* "--no-<option>" */
2109                clear_cas_option(cas);
2110                return 0;
2111        }
2112
2113        if (!arg) {
2114                /* just "--<option>" */
2115                cas->use_tracking_for_rest = 1;
2116                return 0;
2117        }
2118
2119        /* "--<option>=refname" or "--<option>=refname:value" */
2120        colon = strchrnul(arg, ':');
2121        entry = add_cas_entry(cas, arg, colon - arg);
2122        if (!*colon)
2123                entry->use_tracking = 1;
2124        else if (get_sha1(colon + 1, entry->expect))
2125                return error("cannot parse expected object name '%s'", colon + 1);
2126        return 0;
2127}
2128
2129int parseopt_push_cas_option(const struct option *opt, const char *arg, int unset)
2130{
2131        return parse_push_cas_option(opt->value, arg, unset);
2132}
2133
2134int is_empty_cas(const struct push_cas_option *cas)
2135{
2136        return !cas->use_tracking_for_rest && !cas->nr;
2137}
2138
2139/*
2140 * Look at remote.fetch refspec and see if we have a remote
2141 * tracking branch for the refname there.  Fill its current
2142 * value in sha1[].
2143 * If we cannot do so, return negative to signal an error.
2144 */
2145static int remote_tracking(struct remote *remote, const char *refname,
2146                           unsigned char sha1[20])
2147{
2148        char *dst;
2149
2150        dst = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
2151        if (!dst)
2152                return -1; /* no tracking ref for refname at remote */
2153        if (read_ref(dst, sha1))
2154                return -1; /* we know what the tracking ref is but we cannot read it */
2155        return 0;
2156}
2157
2158static void apply_cas(struct push_cas_option *cas,
2159                      struct remote *remote,
2160                      struct ref *ref)
2161{
2162        int i;
2163
2164        /* Find an explicit --<option>=<name>[:<value>] entry */
2165        for (i = 0; i < cas->nr; i++) {
2166                struct push_cas *entry = &cas->entry[i];
2167                if (!refname_match(entry->refname, ref->name))
2168                        continue;
2169                ref->expect_old_sha1 = 1;
2170                if (!entry->use_tracking)
2171                        hashcpy(ref->old_sha1_expect, cas->entry[i].expect);
2172                else if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2173                        ref->expect_old_no_trackback = 1;
2174                return;
2175        }
2176
2177        /* Are we using "--<option>" to cover all? */
2178        if (!cas->use_tracking_for_rest)
2179                return;
2180
2181        ref->expect_old_sha1 = 1;
2182        if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2183                ref->expect_old_no_trackback = 1;
2184}
2185
2186void apply_push_cas(struct push_cas_option *cas,
2187                    struct remote *remote,
2188                    struct ref *remote_refs)
2189{
2190        struct ref *ref;
2191        for (ref = remote_refs; ref; ref = ref->next)
2192                apply_cas(cas, remote, ref);
2193}