remote.con commit Merge branch 'ib/rev-parse-parseopt-argh' (24b9cb1)
   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
 860int query_refspecs(struct refspec *refs, int ref_count, struct refspec *query)
 861{
 862        int i;
 863        int find_src = !query->src;
 864        const char *needle = find_src ? query->dst : query->src;
 865        char **result = find_src ? &query->src : &query->dst;
 866
 867        if (find_src && !query->dst)
 868                return error("query_refspecs: need either src or dst");
 869
 870        for (i = 0; i < ref_count; i++) {
 871                struct refspec *refspec = &refs[i];
 872                const char *key = find_src ? refspec->dst : refspec->src;
 873                const char *value = find_src ? refspec->src : refspec->dst;
 874
 875                if (!refspec->dst)
 876                        continue;
 877                if (refspec->pattern) {
 878                        if (match_name_with_pattern(key, needle, value, result)) {
 879                                query->force = refspec->force;
 880                                return 0;
 881                        }
 882                } else if (!strcmp(needle, key)) {
 883                        *result = xstrdup(value);
 884                        query->force = refspec->force;
 885                        return 0;
 886                }
 887        }
 888        return -1;
 889}
 890
 891char *apply_refspecs(struct refspec *refspecs, int nr_refspec,
 892                     const char *name)
 893{
 894        struct refspec query;
 895
 896        memset(&query, 0, sizeof(struct refspec));
 897        query.src = (char *)name;
 898
 899        if (query_refspecs(refspecs, nr_refspec, &query))
 900                return NULL;
 901
 902        return query.dst;
 903}
 904
 905int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 906{
 907        return query_refspecs(remote->fetch, remote->fetch_refspec_nr, refspec);
 908}
 909
 910static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 911                const char *name)
 912{
 913        size_t len = strlen(name);
 914        struct ref *ref = xcalloc(1, sizeof(struct ref) + prefixlen + len + 1);
 915        memcpy(ref->name, prefix, prefixlen);
 916        memcpy(ref->name + prefixlen, name, len);
 917        return ref;
 918}
 919
 920struct ref *alloc_ref(const char *name)
 921{
 922        return alloc_ref_with_prefix("", 0, name);
 923}
 924
 925struct ref *copy_ref(const struct ref *ref)
 926{
 927        struct ref *cpy;
 928        size_t len;
 929        if (!ref)
 930                return NULL;
 931        len = strlen(ref->name);
 932        cpy = xmalloc(sizeof(struct ref) + len + 1);
 933        memcpy(cpy, ref, sizeof(struct ref) + len + 1);
 934        cpy->next = NULL;
 935        cpy->symref = ref->symref ? xstrdup(ref->symref) : NULL;
 936        cpy->remote_status = ref->remote_status ? xstrdup(ref->remote_status) : NULL;
 937        cpy->peer_ref = copy_ref(ref->peer_ref);
 938        return cpy;
 939}
 940
 941struct ref *copy_ref_list(const struct ref *ref)
 942{
 943        struct ref *ret = NULL;
 944        struct ref **tail = &ret;
 945        while (ref) {
 946                *tail = copy_ref(ref);
 947                ref = ref->next;
 948                tail = &((*tail)->next);
 949        }
 950        return ret;
 951}
 952
 953static void free_ref(struct ref *ref)
 954{
 955        if (!ref)
 956                return;
 957        free_ref(ref->peer_ref);
 958        free(ref->remote_status);
 959        free(ref->symref);
 960        free(ref);
 961}
 962
 963void free_refs(struct ref *ref)
 964{
 965        struct ref *next;
 966        while (ref) {
 967                next = ref->next;
 968                free_ref(ref);
 969                ref = next;
 970        }
 971}
 972
 973int ref_compare_name(const void *va, const void *vb)
 974{
 975        const struct ref *a = va, *b = vb;
 976        return strcmp(a->name, b->name);
 977}
 978
 979static void *ref_list_get_next(const void *a)
 980{
 981        return ((const struct ref *)a)->next;
 982}
 983
 984static void ref_list_set_next(void *a, void *next)
 985{
 986        ((struct ref *)a)->next = next;
 987}
 988
 989void sort_ref_list(struct ref **l, int (*cmp)(const void *, const void *))
 990{
 991        *l = llist_mergesort(*l, ref_list_get_next, ref_list_set_next, cmp);
 992}
 993
 994int count_refspec_match(const char *pattern,
 995                        struct ref *refs,
 996                        struct ref **matched_ref)
 997{
 998        int patlen = strlen(pattern);
 999        struct ref *matched_weak = NULL;
1000        struct ref *matched = NULL;
1001        int weak_match = 0;
1002        int match = 0;
1003
1004        for (weak_match = match = 0; refs; refs = refs->next) {
1005                char *name = refs->name;
1006                int namelen = strlen(name);
1007
1008                if (!refname_match(pattern, name))
1009                        continue;
1010
1011                /* A match is "weak" if it is with refs outside
1012                 * heads or tags, and did not specify the pattern
1013                 * in full (e.g. "refs/remotes/origin/master") or at
1014                 * least from the toplevel (e.g. "remotes/origin/master");
1015                 * otherwise "git push $URL master" would result in
1016                 * ambiguity between remotes/origin/master and heads/master
1017                 * at the remote site.
1018                 */
1019                if (namelen != patlen &&
1020                    patlen != namelen - 5 &&
1021                    !starts_with(name, "refs/heads/") &&
1022                    !starts_with(name, "refs/tags/")) {
1023                        /* We want to catch the case where only weak
1024                         * matches are found and there are multiple
1025                         * matches, and where more than one strong
1026                         * matches are found, as ambiguous.  One
1027                         * strong match with zero or more weak matches
1028                         * are acceptable as a unique match.
1029                         */
1030                        matched_weak = refs;
1031                        weak_match++;
1032                }
1033                else {
1034                        matched = refs;
1035                        match++;
1036                }
1037        }
1038        if (!matched) {
1039                if (matched_ref)
1040                        *matched_ref = matched_weak;
1041                return weak_match;
1042        }
1043        else {
1044                if (matched_ref)
1045                        *matched_ref = matched;
1046                return match;
1047        }
1048}
1049
1050static void tail_link_ref(struct ref *ref, struct ref ***tail)
1051{
1052        **tail = ref;
1053        while (ref->next)
1054                ref = ref->next;
1055        *tail = &ref->next;
1056}
1057
1058static struct ref *alloc_delete_ref(void)
1059{
1060        struct ref *ref = alloc_ref("(delete)");
1061        hashclr(ref->new_sha1);
1062        return ref;
1063}
1064
1065static int try_explicit_object_name(const char *name,
1066                                    struct ref **match)
1067{
1068        unsigned char sha1[20];
1069
1070        if (!*name) {
1071                if (match)
1072                        *match = alloc_delete_ref();
1073                return 0;
1074        }
1075
1076        if (get_sha1(name, sha1))
1077                return -1;
1078
1079        if (match) {
1080                *match = alloc_ref(name);
1081                hashcpy((*match)->new_sha1, sha1);
1082        }
1083        return 0;
1084}
1085
1086static struct ref *make_linked_ref(const char *name, struct ref ***tail)
1087{
1088        struct ref *ret = alloc_ref(name);
1089        tail_link_ref(ret, tail);
1090        return ret;
1091}
1092
1093static char *guess_ref(const char *name, struct ref *peer)
1094{
1095        struct strbuf buf = STRBUF_INIT;
1096        unsigned char sha1[20];
1097
1098        const char *r = resolve_ref_unsafe(peer->name, sha1, 1, NULL);
1099        if (!r)
1100                return NULL;
1101
1102        if (starts_with(r, "refs/heads/"))
1103                strbuf_addstr(&buf, "refs/heads/");
1104        else if (starts_with(r, "refs/tags/"))
1105                strbuf_addstr(&buf, "refs/tags/");
1106        else
1107                return NULL;
1108
1109        strbuf_addstr(&buf, name);
1110        return strbuf_detach(&buf, NULL);
1111}
1112
1113static int match_explicit_lhs(struct ref *src,
1114                              struct refspec *rs,
1115                              struct ref **match,
1116                              int *allocated_match)
1117{
1118        switch (count_refspec_match(rs->src, src, match)) {
1119        case 1:
1120                if (allocated_match)
1121                        *allocated_match = 0;
1122                return 0;
1123        case 0:
1124                /* The source could be in the get_sha1() format
1125                 * not a reference name.  :refs/other is a
1126                 * way to delete 'other' ref at the remote end.
1127                 */
1128                if (try_explicit_object_name(rs->src, match) < 0)
1129                        return error("src refspec %s does not match any.", rs->src);
1130                if (allocated_match)
1131                        *allocated_match = 1;
1132                return 0;
1133        default:
1134                return error("src refspec %s matches more than one.", rs->src);
1135        }
1136}
1137
1138static int match_explicit(struct ref *src, struct ref *dst,
1139                          struct ref ***dst_tail,
1140                          struct refspec *rs)
1141{
1142        struct ref *matched_src, *matched_dst;
1143        int allocated_src;
1144
1145        const char *dst_value = rs->dst;
1146        char *dst_guess;
1147
1148        if (rs->pattern || rs->matching)
1149                return 0;
1150
1151        matched_src = matched_dst = NULL;
1152        if (match_explicit_lhs(src, rs, &matched_src, &allocated_src) < 0)
1153                return -1;
1154
1155        if (!dst_value) {
1156                unsigned char sha1[20];
1157                int flag;
1158
1159                dst_value = resolve_ref_unsafe(matched_src->name, sha1, 1, &flag);
1160                if (!dst_value ||
1161                    ((flag & REF_ISSYMREF) &&
1162                     !starts_with(dst_value, "refs/heads/")))
1163                        die("%s cannot be resolved to branch.",
1164                            matched_src->name);
1165        }
1166
1167        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
1168        case 1:
1169                break;
1170        case 0:
1171                if (!memcmp(dst_value, "refs/", 5))
1172                        matched_dst = make_linked_ref(dst_value, dst_tail);
1173                else if (is_null_sha1(matched_src->new_sha1))
1174                        error("unable to delete '%s': remote ref does not exist",
1175                              dst_value);
1176                else if ((dst_guess = guess_ref(dst_value, matched_src)))
1177                        matched_dst = make_linked_ref(dst_guess, dst_tail);
1178                else
1179                        error("unable to push to unqualified destination: %s\n"
1180                              "The destination refspec neither matches an "
1181                              "existing ref on the remote nor\n"
1182                              "begins with refs/, and we are unable to "
1183                              "guess a prefix based on the source ref.",
1184                              dst_value);
1185                break;
1186        default:
1187                matched_dst = NULL;
1188                error("dst refspec %s matches more than one.",
1189                      dst_value);
1190                break;
1191        }
1192        if (!matched_dst)
1193                return -1;
1194        if (matched_dst->peer_ref)
1195                return error("dst ref %s receives from more than one src.",
1196                      matched_dst->name);
1197        else {
1198                matched_dst->peer_ref = allocated_src ?
1199                                        matched_src :
1200                                        copy_ref(matched_src);
1201                matched_dst->force = rs->force;
1202        }
1203        return 0;
1204}
1205
1206static int match_explicit_refs(struct ref *src, struct ref *dst,
1207                               struct ref ***dst_tail, struct refspec *rs,
1208                               int rs_nr)
1209{
1210        int i, errs;
1211        for (i = errs = 0; i < rs_nr; i++)
1212                errs += match_explicit(src, dst, dst_tail, &rs[i]);
1213        return errs;
1214}
1215
1216static char *get_ref_match(const struct refspec *rs, int rs_nr, const struct ref *ref,
1217                int send_mirror, int direction, const struct refspec **ret_pat)
1218{
1219        const struct refspec *pat;
1220        char *name;
1221        int i;
1222        int matching_refs = -1;
1223        for (i = 0; i < rs_nr; i++) {
1224                if (rs[i].matching &&
1225                    (matching_refs == -1 || rs[i].force)) {
1226                        matching_refs = i;
1227                        continue;
1228                }
1229
1230                if (rs[i].pattern) {
1231                        const char *dst_side = rs[i].dst ? rs[i].dst : rs[i].src;
1232                        int match;
1233                        if (direction == FROM_SRC)
1234                                match = match_name_with_pattern(rs[i].src, ref->name, dst_side, &name);
1235                        else
1236                                match = match_name_with_pattern(dst_side, ref->name, rs[i].src, &name);
1237                        if (match) {
1238                                matching_refs = i;
1239                                break;
1240                        }
1241                }
1242        }
1243        if (matching_refs == -1)
1244                return NULL;
1245
1246        pat = rs + matching_refs;
1247        if (pat->matching) {
1248                /*
1249                 * "matching refs"; traditionally we pushed everything
1250                 * including refs outside refs/heads/ hierarchy, but
1251                 * that does not make much sense these days.
1252                 */
1253                if (!send_mirror && !starts_with(ref->name, "refs/heads/"))
1254                        return NULL;
1255                name = xstrdup(ref->name);
1256        }
1257        if (ret_pat)
1258                *ret_pat = pat;
1259        return name;
1260}
1261
1262static struct ref **tail_ref(struct ref **head)
1263{
1264        struct ref **tail = head;
1265        while (*tail)
1266                tail = &((*tail)->next);
1267        return tail;
1268}
1269
1270struct tips {
1271        struct commit **tip;
1272        int nr, alloc;
1273};
1274
1275static void add_to_tips(struct tips *tips, const unsigned char *sha1)
1276{
1277        struct commit *commit;
1278
1279        if (is_null_sha1(sha1))
1280                return;
1281        commit = lookup_commit_reference_gently(sha1, 1);
1282        if (!commit || (commit->object.flags & TMP_MARK))
1283                return;
1284        commit->object.flags |= TMP_MARK;
1285        ALLOC_GROW(tips->tip, tips->nr + 1, tips->alloc);
1286        tips->tip[tips->nr++] = commit;
1287}
1288
1289static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***dst_tail)
1290{
1291        struct string_list dst_tag = STRING_LIST_INIT_NODUP;
1292        struct string_list src_tag = STRING_LIST_INIT_NODUP;
1293        struct string_list_item *item;
1294        struct ref *ref;
1295        struct tips sent_tips;
1296
1297        /*
1298         * Collect everything we know they would have at the end of
1299         * this push, and collect all tags they have.
1300         */
1301        memset(&sent_tips, 0, sizeof(sent_tips));
1302        for (ref = *dst; ref; ref = ref->next) {
1303                if (ref->peer_ref &&
1304                    !is_null_sha1(ref->peer_ref->new_sha1))
1305                        add_to_tips(&sent_tips, ref->peer_ref->new_sha1);
1306                else
1307                        add_to_tips(&sent_tips, ref->old_sha1);
1308                if (starts_with(ref->name, "refs/tags/"))
1309                        string_list_append(&dst_tag, ref->name);
1310        }
1311        clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
1312
1313        sort_string_list(&dst_tag);
1314
1315        /* Collect tags they do not have. */
1316        for (ref = src; ref; ref = ref->next) {
1317                if (!starts_with(ref->name, "refs/tags/"))
1318                        continue; /* not a tag */
1319                if (string_list_has_string(&dst_tag, ref->name))
1320                        continue; /* they already have it */
1321                if (sha1_object_info(ref->new_sha1, NULL) != OBJ_TAG)
1322                        continue; /* be conservative */
1323                item = string_list_append(&src_tag, ref->name);
1324                item->util = ref;
1325        }
1326        string_list_clear(&dst_tag, 0);
1327
1328        /*
1329         * At this point, src_tag lists tags that are missing from
1330         * dst, and sent_tips lists the tips we are pushing or those
1331         * that we know they already have. An element in the src_tag
1332         * that is an ancestor of any of the sent_tips needs to be
1333         * sent to the other side.
1334         */
1335        if (sent_tips.nr) {
1336                for_each_string_list_item(item, &src_tag) {
1337                        struct ref *ref = item->util;
1338                        struct ref *dst_ref;
1339                        struct commit *commit;
1340
1341                        if (is_null_sha1(ref->new_sha1))
1342                                continue;
1343                        commit = lookup_commit_reference_gently(ref->new_sha1, 1);
1344                        if (!commit)
1345                                /* not pushing a commit, which is not an error */
1346                                continue;
1347
1348                        /*
1349                         * Is this tag, which they do not have, reachable from
1350                         * any of the commits we are sending?
1351                         */
1352                        if (!in_merge_bases_many(commit, sent_tips.nr, sent_tips.tip))
1353                                continue;
1354
1355                        /* Add it in */
1356                        dst_ref = make_linked_ref(ref->name, dst_tail);
1357                        hashcpy(dst_ref->new_sha1, ref->new_sha1);
1358                        dst_ref->peer_ref = copy_ref(ref);
1359                }
1360        }
1361        string_list_clear(&src_tag, 0);
1362        free(sent_tips.tip);
1363}
1364
1365struct ref *find_ref_by_name(const struct ref *list, const char *name)
1366{
1367        for ( ; list; list = list->next)
1368                if (!strcmp(list->name, name))
1369                        return (struct ref *)list;
1370        return NULL;
1371}
1372
1373static void prepare_ref_index(struct string_list *ref_index, struct ref *ref)
1374{
1375        for ( ; ref; ref = ref->next)
1376                string_list_append_nodup(ref_index, ref->name)->util = ref;
1377
1378        sort_string_list(ref_index);
1379}
1380
1381/*
1382 * Given only the set of local refs, sanity-check the set of push
1383 * refspecs. We can't catch all errors that match_push_refs would,
1384 * but we can catch some errors early before even talking to the
1385 * remote side.
1386 */
1387int check_push_refs(struct ref *src, int nr_refspec, const char **refspec_names)
1388{
1389        struct refspec *refspec = parse_push_refspec(nr_refspec, refspec_names);
1390        int ret = 0;
1391        int i;
1392
1393        for (i = 0; i < nr_refspec; i++) {
1394                struct refspec *rs = refspec + i;
1395
1396                if (rs->pattern || rs->matching)
1397                        continue;
1398
1399                ret |= match_explicit_lhs(src, rs, NULL, NULL);
1400        }
1401
1402        free_refspec(nr_refspec, refspec);
1403        return ret;
1404}
1405
1406/*
1407 * Given the set of refs the local repository has, the set of refs the
1408 * remote repository has, and the refspec used for push, determine
1409 * what remote refs we will update and with what value by setting
1410 * peer_ref (which object is being pushed) and force (if the push is
1411 * forced) in elements of "dst". The function may add new elements to
1412 * dst (e.g. pushing to a new branch, done in match_explicit_refs).
1413 */
1414int match_push_refs(struct ref *src, struct ref **dst,
1415                    int nr_refspec, const char **refspec, int flags)
1416{
1417        struct refspec *rs;
1418        int send_all = flags & MATCH_REFS_ALL;
1419        int send_mirror = flags & MATCH_REFS_MIRROR;
1420        int send_prune = flags & MATCH_REFS_PRUNE;
1421        int errs;
1422        static const char *default_refspec[] = { ":", NULL };
1423        struct ref *ref, **dst_tail = tail_ref(dst);
1424        struct string_list dst_ref_index = STRING_LIST_INIT_NODUP;
1425
1426        if (!nr_refspec) {
1427                nr_refspec = 1;
1428                refspec = default_refspec;
1429        }
1430        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1431        errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
1432
1433        /* pick the remainder */
1434        for (ref = src; ref; ref = ref->next) {
1435                struct string_list_item *dst_item;
1436                struct ref *dst_peer;
1437                const struct refspec *pat = NULL;
1438                char *dst_name;
1439
1440                dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
1441                if (!dst_name)
1442                        continue;
1443
1444                if (!dst_ref_index.nr)
1445                        prepare_ref_index(&dst_ref_index, *dst);
1446
1447                dst_item = string_list_lookup(&dst_ref_index, dst_name);
1448                dst_peer = dst_item ? dst_item->util : NULL;
1449                if (dst_peer) {
1450                        if (dst_peer->peer_ref)
1451                                /* We're already sending something to this ref. */
1452                                goto free_name;
1453                } else {
1454                        if (pat->matching && !(send_all || send_mirror))
1455                                /*
1456                                 * Remote doesn't have it, and we have no
1457                                 * explicit pattern, and we don't have
1458                                 * --all nor --mirror.
1459                                 */
1460                                goto free_name;
1461
1462                        /* Create a new one and link it */
1463                        dst_peer = make_linked_ref(dst_name, &dst_tail);
1464                        hashcpy(dst_peer->new_sha1, ref->new_sha1);
1465                        string_list_insert(&dst_ref_index,
1466                                dst_peer->name)->util = dst_peer;
1467                }
1468                dst_peer->peer_ref = copy_ref(ref);
1469                dst_peer->force = pat->force;
1470        free_name:
1471                free(dst_name);
1472        }
1473
1474        string_list_clear(&dst_ref_index, 0);
1475
1476        if (flags & MATCH_REFS_FOLLOW_TAGS)
1477                add_missing_tags(src, dst, &dst_tail);
1478
1479        if (send_prune) {
1480                struct string_list src_ref_index = STRING_LIST_INIT_NODUP;
1481                /* check for missing refs on the remote */
1482                for (ref = *dst; ref; ref = ref->next) {
1483                        char *src_name;
1484
1485                        if (ref->peer_ref)
1486                                /* We're already sending something to this ref. */
1487                                continue;
1488
1489                        src_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_DST, NULL);
1490                        if (src_name) {
1491                                if (!src_ref_index.nr)
1492                                        prepare_ref_index(&src_ref_index, src);
1493                                if (!string_list_has_string(&src_ref_index,
1494                                            src_name))
1495                                        ref->peer_ref = alloc_delete_ref();
1496                                free(src_name);
1497                        }
1498                }
1499                string_list_clear(&src_ref_index, 0);
1500        }
1501        if (errs)
1502                return -1;
1503        return 0;
1504}
1505
1506void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
1507                             int force_update)
1508{
1509        struct ref *ref;
1510
1511        for (ref = remote_refs; ref; ref = ref->next) {
1512                int force_ref_update = ref->force || force_update;
1513                int reject_reason = 0;
1514
1515                if (ref->peer_ref)
1516                        hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
1517                else if (!send_mirror)
1518                        continue;
1519
1520                ref->deletion = is_null_sha1(ref->new_sha1);
1521                if (!ref->deletion &&
1522                        !hashcmp(ref->old_sha1, ref->new_sha1)) {
1523                        ref->status = REF_STATUS_UPTODATE;
1524                        continue;
1525                }
1526
1527                /*
1528                 * Bypass the usual "must fast-forward" check but
1529                 * replace it with a weaker "the old value must be
1530                 * this value we observed".  If the remote ref has
1531                 * moved and is now different from what we expect,
1532                 * reject any push.
1533                 *
1534                 * It also is an error if the user told us to check
1535                 * with the remote-tracking branch to find the value
1536                 * to expect, but we did not have such a tracking
1537                 * branch.
1538                 */
1539                if (ref->expect_old_sha1) {
1540                        if (ref->expect_old_no_trackback ||
1541                            hashcmp(ref->old_sha1, ref->old_sha1_expect))
1542                                reject_reason = REF_STATUS_REJECT_STALE;
1543                }
1544
1545                /*
1546                 * The usual "must fast-forward" rules.
1547                 *
1548                 * Decide whether an individual refspec A:B can be
1549                 * pushed.  The push will succeed if any of the
1550                 * following are true:
1551                 *
1552                 * (1) the remote reference B does not exist
1553                 *
1554                 * (2) the remote reference B is being removed (i.e.,
1555                 *     pushing :B where no source is specified)
1556                 *
1557                 * (3) the destination is not under refs/tags/, and
1558                 *     if the old and new value is a commit, the new
1559                 *     is a descendant of the old.
1560                 *
1561                 * (4) it is forced using the +A:B notation, or by
1562                 *     passing the --force argument
1563                 */
1564
1565                else if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
1566                        if (starts_with(ref->name, "refs/tags/"))
1567                                reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
1568                        else if (!has_sha1_file(ref->old_sha1))
1569                                reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
1570                        else if (!lookup_commit_reference_gently(ref->old_sha1, 1) ||
1571                                 !lookup_commit_reference_gently(ref->new_sha1, 1))
1572                                reject_reason = REF_STATUS_REJECT_NEEDS_FORCE;
1573                        else if (!ref_newer(ref->new_sha1, ref->old_sha1))
1574                                reject_reason = REF_STATUS_REJECT_NONFASTFORWARD;
1575                }
1576
1577                /*
1578                 * "--force" will defeat any rejection implemented
1579                 * by the rules above.
1580                 */
1581                if (!force_ref_update)
1582                        ref->status = reject_reason;
1583                else if (reject_reason)
1584                        ref->forced_update = 1;
1585        }
1586}
1587
1588struct branch *branch_get(const char *name)
1589{
1590        struct branch *ret;
1591
1592        read_config();
1593        if (!name || !*name || !strcmp(name, "HEAD"))
1594                ret = current_branch;
1595        else
1596                ret = make_branch(name, 0);
1597        if (ret && ret->remote_name) {
1598                ret->remote = remote_get(ret->remote_name);
1599                if (ret->merge_nr) {
1600                        int i;
1601                        ret->merge = xcalloc(ret->merge_nr, sizeof(*ret->merge));
1602                        for (i = 0; i < ret->merge_nr; i++) {
1603                                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1604                                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1605                                if (remote_find_tracking(ret->remote, ret->merge[i])
1606                                    && !strcmp(ret->remote_name, "."))
1607                                        ret->merge[i]->dst = xstrdup(ret->merge_name[i]);
1608                        }
1609                }
1610        }
1611        return ret;
1612}
1613
1614int branch_has_merge_config(struct branch *branch)
1615{
1616        return branch && !!branch->merge;
1617}
1618
1619int branch_merge_matches(struct branch *branch,
1620                                 int i,
1621                                 const char *refname)
1622{
1623        if (!branch || i < 0 || i >= branch->merge_nr)
1624                return 0;
1625        return refname_match(branch->merge[i]->src, refname);
1626}
1627
1628static int ignore_symref_update(const char *refname)
1629{
1630        unsigned char sha1[20];
1631        int flag;
1632
1633        if (!resolve_ref_unsafe(refname, sha1, 0, &flag))
1634                return 0; /* non-existing refs are OK */
1635        return (flag & REF_ISSYMREF);
1636}
1637
1638/*
1639 * Create and return a list of (struct ref) consisting of copies of
1640 * each remote_ref that matches refspec.  refspec must be a pattern.
1641 * Fill in the copies' peer_ref to describe the local tracking refs to
1642 * which they map.  Omit any references that would map to an existing
1643 * local symbolic ref.
1644 */
1645static struct ref *get_expanded_map(const struct ref *remote_refs,
1646                                    const struct refspec *refspec)
1647{
1648        const struct ref *ref;
1649        struct ref *ret = NULL;
1650        struct ref **tail = &ret;
1651
1652        for (ref = remote_refs; ref; ref = ref->next) {
1653                char *expn_name = NULL;
1654
1655                if (strchr(ref->name, '^'))
1656                        continue; /* a dereference item */
1657                if (match_name_with_pattern(refspec->src, ref->name,
1658                                            refspec->dst, &expn_name) &&
1659                    !ignore_symref_update(expn_name)) {
1660                        struct ref *cpy = copy_ref(ref);
1661
1662                        cpy->peer_ref = alloc_ref(expn_name);
1663                        if (refspec->force)
1664                                cpy->peer_ref->force = 1;
1665                        *tail = cpy;
1666                        tail = &cpy->next;
1667                }
1668                free(expn_name);
1669        }
1670
1671        return ret;
1672}
1673
1674static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1675{
1676        const struct ref *ref;
1677        for (ref = refs; ref; ref = ref->next) {
1678                if (refname_match(name, ref->name))
1679                        return ref;
1680        }
1681        return NULL;
1682}
1683
1684struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1685{
1686        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1687
1688        if (!ref)
1689                return NULL;
1690
1691        return copy_ref(ref);
1692}
1693
1694static struct ref *get_local_ref(const char *name)
1695{
1696        if (!name || name[0] == '\0')
1697                return NULL;
1698
1699        if (starts_with(name, "refs/"))
1700                return alloc_ref(name);
1701
1702        if (starts_with(name, "heads/") ||
1703            starts_with(name, "tags/") ||
1704            starts_with(name, "remotes/"))
1705                return alloc_ref_with_prefix("refs/", 5, name);
1706
1707        return alloc_ref_with_prefix("refs/heads/", 11, name);
1708}
1709
1710int get_fetch_map(const struct ref *remote_refs,
1711                  const struct refspec *refspec,
1712                  struct ref ***tail,
1713                  int missing_ok)
1714{
1715        struct ref *ref_map, **rmp;
1716
1717        if (refspec->pattern) {
1718                ref_map = get_expanded_map(remote_refs, refspec);
1719        } else {
1720                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1721
1722                if (refspec->exact_sha1) {
1723                        ref_map = alloc_ref(name);
1724                        get_sha1_hex(name, ref_map->old_sha1);
1725                } else {
1726                        ref_map = get_remote_ref(remote_refs, name);
1727                }
1728                if (!missing_ok && !ref_map)
1729                        die("Couldn't find remote ref %s", name);
1730                if (ref_map) {
1731                        ref_map->peer_ref = get_local_ref(refspec->dst);
1732                        if (ref_map->peer_ref && refspec->force)
1733                                ref_map->peer_ref->force = 1;
1734                }
1735        }
1736
1737        for (rmp = &ref_map; *rmp; ) {
1738                if ((*rmp)->peer_ref) {
1739                        if (!starts_with((*rmp)->peer_ref->name, "refs/") ||
1740                            check_refname_format((*rmp)->peer_ref->name, 0)) {
1741                                struct ref *ignore = *rmp;
1742                                error("* Ignoring funny ref '%s' locally",
1743                                      (*rmp)->peer_ref->name);
1744                                *rmp = (*rmp)->next;
1745                                free(ignore->peer_ref);
1746                                free(ignore);
1747                                continue;
1748                        }
1749                }
1750                rmp = &((*rmp)->next);
1751        }
1752
1753        if (ref_map)
1754                tail_link_ref(ref_map, tail);
1755
1756        return 0;
1757}
1758
1759int resolve_remote_symref(struct ref *ref, struct ref *list)
1760{
1761        if (!ref->symref)
1762                return 0;
1763        for (; list; list = list->next)
1764                if (!strcmp(ref->symref, list->name)) {
1765                        hashcpy(ref->old_sha1, list->old_sha1);
1766                        return 0;
1767                }
1768        return 1;
1769}
1770
1771static void unmark_and_free(struct commit_list *list, unsigned int mark)
1772{
1773        while (list) {
1774                struct commit_list *temp = list;
1775                temp->item->object.flags &= ~mark;
1776                list = temp->next;
1777                free(temp);
1778        }
1779}
1780
1781int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
1782{
1783        struct object *o;
1784        struct commit *old, *new;
1785        struct commit_list *list, *used;
1786        int found = 0;
1787
1788        /*
1789         * Both new and old must be commit-ish and new is descendant of
1790         * old.  Otherwise we require --force.
1791         */
1792        o = deref_tag(parse_object(old_sha1), NULL, 0);
1793        if (!o || o->type != OBJ_COMMIT)
1794                return 0;
1795        old = (struct commit *) o;
1796
1797        o = deref_tag(parse_object(new_sha1), NULL, 0);
1798        if (!o || o->type != OBJ_COMMIT)
1799                return 0;
1800        new = (struct commit *) o;
1801
1802        if (parse_commit(new) < 0)
1803                return 0;
1804
1805        used = list = NULL;
1806        commit_list_insert(new, &list);
1807        while (list) {
1808                new = pop_most_recent_commit(&list, TMP_MARK);
1809                commit_list_insert(new, &used);
1810                if (new == old) {
1811                        found = 1;
1812                        break;
1813                }
1814        }
1815        unmark_and_free(list, TMP_MARK);
1816        unmark_and_free(used, TMP_MARK);
1817        return found;
1818}
1819
1820/*
1821 * Compare a branch with its upstream, and save their differences (number
1822 * of commits) in *num_ours and *num_theirs.
1823 *
1824 * Return 0 if branch has no upstream (no base), -1 if upstream is missing
1825 * (with "gone" base), otherwise 1 (with base).
1826 */
1827int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
1828{
1829        unsigned char sha1[20];
1830        struct commit *ours, *theirs;
1831        char symmetric[84];
1832        struct rev_info revs;
1833        const char *rev_argv[10], *base;
1834        int rev_argc;
1835
1836        /* Cannot stat unless we are marked to build on top of somebody else. */
1837        if (!branch ||
1838            !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
1839                return 0;
1840
1841        /* Cannot stat if what we used to build on no longer exists */
1842        base = branch->merge[0]->dst;
1843        if (read_ref(base, sha1))
1844                return -1;
1845        theirs = lookup_commit_reference(sha1);
1846        if (!theirs)
1847                return -1;
1848
1849        if (read_ref(branch->refname, sha1))
1850                return -1;
1851        ours = lookup_commit_reference(sha1);
1852        if (!ours)
1853                return -1;
1854
1855        /* are we the same? */
1856        if (theirs == ours) {
1857                *num_theirs = *num_ours = 0;
1858                return 1;
1859        }
1860
1861        /* Run "rev-list --left-right ours...theirs" internally... */
1862        rev_argc = 0;
1863        rev_argv[rev_argc++] = NULL;
1864        rev_argv[rev_argc++] = "--left-right";
1865        rev_argv[rev_argc++] = symmetric;
1866        rev_argv[rev_argc++] = "--";
1867        rev_argv[rev_argc] = NULL;
1868
1869        strcpy(symmetric, sha1_to_hex(ours->object.sha1));
1870        strcpy(symmetric + 40, "...");
1871        strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
1872
1873        init_revisions(&revs, NULL);
1874        setup_revisions(rev_argc, rev_argv, &revs, NULL);
1875        prepare_revision_walk(&revs);
1876
1877        /* ... and count the commits on each side. */
1878        *num_ours = 0;
1879        *num_theirs = 0;
1880        while (1) {
1881                struct commit *c = get_revision(&revs);
1882                if (!c)
1883                        break;
1884                if (c->object.flags & SYMMETRIC_LEFT)
1885                        (*num_ours)++;
1886                else
1887                        (*num_theirs)++;
1888        }
1889
1890        /* clear object flags smudged by the above traversal */
1891        clear_commit_marks(ours, ALL_REV_FLAGS);
1892        clear_commit_marks(theirs, ALL_REV_FLAGS);
1893        return 1;
1894}
1895
1896/*
1897 * Return true when there is anything to report, otherwise false.
1898 */
1899int format_tracking_info(struct branch *branch, struct strbuf *sb)
1900{
1901        int ours, theirs;
1902        const char *base;
1903        int upstream_is_gone = 0;
1904
1905        switch (stat_tracking_info(branch, &ours, &theirs)) {
1906        case 0:
1907                /* no base */
1908                return 0;
1909        case -1:
1910                /* with "gone" base */
1911                upstream_is_gone = 1;
1912                break;
1913        default:
1914                /* with base */
1915                break;
1916        }
1917
1918        base = branch->merge[0]->dst;
1919        base = shorten_unambiguous_ref(base, 0);
1920        if (upstream_is_gone) {
1921                strbuf_addf(sb,
1922                        _("Your branch is based on '%s', but the upstream is gone.\n"),
1923                        base);
1924                if (advice_status_hints)
1925                        strbuf_addf(sb,
1926                                _("  (use \"git branch --unset-upstream\" to fixup)\n"));
1927        } else if (!ours && !theirs) {
1928                strbuf_addf(sb,
1929                        _("Your branch is up-to-date with '%s'.\n"),
1930                        base);
1931        } else if (!theirs) {
1932                strbuf_addf(sb,
1933                        Q_("Your branch is ahead of '%s' by %d commit.\n",
1934                           "Your branch is ahead of '%s' by %d commits.\n",
1935                           ours),
1936                        base, ours);
1937                if (advice_status_hints)
1938                        strbuf_addf(sb,
1939                                _("  (use \"git push\" to publish your local commits)\n"));
1940        } else if (!ours) {
1941                strbuf_addf(sb,
1942                        Q_("Your branch is behind '%s' by %d commit, "
1943                               "and can be fast-forwarded.\n",
1944                           "Your branch is behind '%s' by %d commits, "
1945                               "and can be fast-forwarded.\n",
1946                           theirs),
1947                        base, theirs);
1948                if (advice_status_hints)
1949                        strbuf_addf(sb,
1950                                _("  (use \"git pull\" to update your local branch)\n"));
1951        } else {
1952                strbuf_addf(sb,
1953                        Q_("Your branch and '%s' have diverged,\n"
1954                               "and have %d and %d different commit each, "
1955                               "respectively.\n",
1956                           "Your branch and '%s' have diverged,\n"
1957                               "and have %d and %d different commits each, "
1958                               "respectively.\n",
1959                           theirs),
1960                        base, ours, theirs);
1961                if (advice_status_hints)
1962                        strbuf_addf(sb,
1963                                _("  (use \"git pull\" to merge the remote branch into yours)\n"));
1964        }
1965        return 1;
1966}
1967
1968static int one_local_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
1969{
1970        struct ref ***local_tail = cb_data;
1971        struct ref *ref;
1972        int len;
1973
1974        /* we already know it starts with refs/ to get here */
1975        if (check_refname_format(refname + 5, 0))
1976                return 0;
1977
1978        len = strlen(refname) + 1;
1979        ref = xcalloc(1, sizeof(*ref) + len);
1980        hashcpy(ref->new_sha1, sha1);
1981        memcpy(ref->name, refname, len);
1982        **local_tail = ref;
1983        *local_tail = &ref->next;
1984        return 0;
1985}
1986
1987struct ref *get_local_heads(void)
1988{
1989        struct ref *local_refs = NULL, **local_tail = &local_refs;
1990        for_each_ref(one_local_ref, &local_tail);
1991        return local_refs;
1992}
1993
1994struct ref *guess_remote_head(const struct ref *head,
1995                              const struct ref *refs,
1996                              int all)
1997{
1998        const struct ref *r;
1999        struct ref *list = NULL;
2000        struct ref **tail = &list;
2001
2002        if (!head)
2003                return NULL;
2004
2005        /*
2006         * Some transports support directly peeking at
2007         * where HEAD points; if that is the case, then
2008         * we don't have to guess.
2009         */
2010        if (head->symref)
2011                return copy_ref(find_ref_by_name(refs, head->symref));
2012
2013        /* If refs/heads/master could be right, it is. */
2014        if (!all) {
2015                r = find_ref_by_name(refs, "refs/heads/master");
2016                if (r && !hashcmp(r->old_sha1, head->old_sha1))
2017                        return copy_ref(r);
2018        }
2019
2020        /* Look for another ref that points there */
2021        for (r = refs; r; r = r->next) {
2022                if (r != head &&
2023                    starts_with(r->name, "refs/heads/") &&
2024                    !hashcmp(r->old_sha1, head->old_sha1)) {
2025                        *tail = copy_ref(r);
2026                        tail = &((*tail)->next);
2027                        if (!all)
2028                                break;
2029                }
2030        }
2031
2032        return list;
2033}
2034
2035struct stale_heads_info {
2036        struct string_list *ref_names;
2037        struct ref **stale_refs_tail;
2038        struct refspec *refs;
2039        int ref_count;
2040};
2041
2042static int get_stale_heads_cb(const char *refname,
2043        const unsigned char *sha1, int flags, void *cb_data)
2044{
2045        struct stale_heads_info *info = cb_data;
2046        struct refspec query;
2047        memset(&query, 0, sizeof(struct refspec));
2048        query.dst = (char *)refname;
2049
2050        if (query_refspecs(info->refs, info->ref_count, &query))
2051                return 0; /* No matches */
2052
2053        /*
2054         * If we did find a suitable refspec and it's not a symref and
2055         * it's not in the list of refs that currently exist in that
2056         * remote we consider it to be stale.
2057         */
2058        if (!((flags & REF_ISSYMREF) ||
2059              string_list_has_string(info->ref_names, query.src))) {
2060                struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
2061                hashcpy(ref->new_sha1, sha1);
2062        }
2063
2064        free(query.src);
2065        return 0;
2066}
2067
2068struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fetch_map)
2069{
2070        struct ref *ref, *stale_refs = NULL;
2071        struct string_list ref_names = STRING_LIST_INIT_NODUP;
2072        struct stale_heads_info info;
2073        info.ref_names = &ref_names;
2074        info.stale_refs_tail = &stale_refs;
2075        info.refs = refs;
2076        info.ref_count = ref_count;
2077        for (ref = fetch_map; ref; ref = ref->next)
2078                string_list_append(&ref_names, ref->name);
2079        sort_string_list(&ref_names);
2080        for_each_ref(get_stale_heads_cb, &info);
2081        string_list_clear(&ref_names, 0);
2082        return stale_refs;
2083}
2084
2085/*
2086 * Compare-and-swap
2087 */
2088void clear_cas_option(struct push_cas_option *cas)
2089{
2090        int i;
2091
2092        for (i = 0; i < cas->nr; i++)
2093                free(cas->entry[i].refname);
2094        free(cas->entry);
2095        memset(cas, 0, sizeof(*cas));
2096}
2097
2098static struct push_cas *add_cas_entry(struct push_cas_option *cas,
2099                                      const char *refname,
2100                                      size_t refnamelen)
2101{
2102        struct push_cas *entry;
2103        ALLOC_GROW(cas->entry, cas->nr + 1, cas->alloc);
2104        entry = &cas->entry[cas->nr++];
2105        memset(entry, 0, sizeof(*entry));
2106        entry->refname = xmemdupz(refname, refnamelen);
2107        return entry;
2108}
2109
2110int parse_push_cas_option(struct push_cas_option *cas, const char *arg, int unset)
2111{
2112        const char *colon;
2113        struct push_cas *entry;
2114
2115        if (unset) {
2116                /* "--no-<option>" */
2117                clear_cas_option(cas);
2118                return 0;
2119        }
2120
2121        if (!arg) {
2122                /* just "--<option>" */
2123                cas->use_tracking_for_rest = 1;
2124                return 0;
2125        }
2126
2127        /* "--<option>=refname" or "--<option>=refname:value" */
2128        colon = strchrnul(arg, ':');
2129        entry = add_cas_entry(cas, arg, colon - arg);
2130        if (!*colon)
2131                entry->use_tracking = 1;
2132        else if (get_sha1(colon + 1, entry->expect))
2133                return error("cannot parse expected object name '%s'", colon + 1);
2134        return 0;
2135}
2136
2137int parseopt_push_cas_option(const struct option *opt, const char *arg, int unset)
2138{
2139        return parse_push_cas_option(opt->value, arg, unset);
2140}
2141
2142int is_empty_cas(const struct push_cas_option *cas)
2143{
2144        return !cas->use_tracking_for_rest && !cas->nr;
2145}
2146
2147/*
2148 * Look at remote.fetch refspec and see if we have a remote
2149 * tracking branch for the refname there.  Fill its current
2150 * value in sha1[].
2151 * If we cannot do so, return negative to signal an error.
2152 */
2153static int remote_tracking(struct remote *remote, const char *refname,
2154                           unsigned char sha1[20])
2155{
2156        char *dst;
2157
2158        dst = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
2159        if (!dst)
2160                return -1; /* no tracking ref for refname at remote */
2161        if (read_ref(dst, sha1))
2162                return -1; /* we know what the tracking ref is but we cannot read it */
2163        return 0;
2164}
2165
2166static void apply_cas(struct push_cas_option *cas,
2167                      struct remote *remote,
2168                      struct ref *ref)
2169{
2170        int i;
2171
2172        /* Find an explicit --<option>=<name>[:<value>] entry */
2173        for (i = 0; i < cas->nr; i++) {
2174                struct push_cas *entry = &cas->entry[i];
2175                if (!refname_match(entry->refname, ref->name))
2176                        continue;
2177                ref->expect_old_sha1 = 1;
2178                if (!entry->use_tracking)
2179                        hashcpy(ref->old_sha1_expect, cas->entry[i].expect);
2180                else if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2181                        ref->expect_old_no_trackback = 1;
2182                return;
2183        }
2184
2185        /* Are we using "--<option>" to cover all? */
2186        if (!cas->use_tracking_for_rest)
2187                return;
2188
2189        ref->expect_old_sha1 = 1;
2190        if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2191                ref->expect_old_no_trackback = 1;
2192}
2193
2194void apply_push_cas(struct push_cas_option *cas,
2195                    struct remote *remote,
2196                    struct ref *remote_refs)
2197{
2198        struct ref *ref;
2199        for (ref = remote_refs; ref; ref = ref->next)
2200                apply_cas(cas, remote, ref);
2201}