remote.con commit t5533: test "push --force-with-lease" (d887cc1)
   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 *pushremote_name;
  53static int explicit_default_remote_name;
  54
  55static struct rewrites rewrites;
  56static struct rewrites rewrites_push;
  57
  58#define BUF_SIZE (2048)
  59static char buffer[BUF_SIZE];
  60
  61static int valid_remote(const struct remote *remote)
  62{
  63        return (!!remote->url) || (!!remote->foreign_vcs);
  64}
  65
  66static const char *alias_url(const char *url, struct rewrites *r)
  67{
  68        int i, j;
  69        char *ret;
  70        struct counted_string *longest;
  71        int longest_i;
  72
  73        longest = NULL;
  74        longest_i = -1;
  75        for (i = 0; i < r->rewrite_nr; i++) {
  76                if (!r->rewrite[i])
  77                        continue;
  78                for (j = 0; j < r->rewrite[i]->instead_of_nr; j++) {
  79                        if (!prefixcmp(url, r->rewrite[i]->instead_of[j].s) &&
  80                            (!longest ||
  81                             longest->len < r->rewrite[i]->instead_of[j].len)) {
  82                                longest = &(r->rewrite[i]->instead_of[j]);
  83                                longest_i = i;
  84                        }
  85                }
  86        }
  87        if (!longest)
  88                return url;
  89
  90        ret = xmalloc(r->rewrite[longest_i]->baselen +
  91                     (strlen(url) - longest->len) + 1);
  92        strcpy(ret, r->rewrite[longest_i]->base);
  93        strcpy(ret + r->rewrite[longest_i]->baselen, url + longest->len);
  94        return ret;
  95}
  96
  97static void add_push_refspec(struct remote *remote, const char *ref)
  98{
  99        ALLOC_GROW(remote->push_refspec,
 100                   remote->push_refspec_nr + 1,
 101                   remote->push_refspec_alloc);
 102        remote->push_refspec[remote->push_refspec_nr++] = ref;
 103}
 104
 105static void add_fetch_refspec(struct remote *remote, const char *ref)
 106{
 107        ALLOC_GROW(remote->fetch_refspec,
 108                   remote->fetch_refspec_nr + 1,
 109                   remote->fetch_refspec_alloc);
 110        remote->fetch_refspec[remote->fetch_refspec_nr++] = ref;
 111}
 112
 113static void add_url(struct remote *remote, const char *url)
 114{
 115        ALLOC_GROW(remote->url, remote->url_nr + 1, remote->url_alloc);
 116        remote->url[remote->url_nr++] = url;
 117}
 118
 119static void add_pushurl(struct remote *remote, const char *pushurl)
 120{
 121        ALLOC_GROW(remote->pushurl, remote->pushurl_nr + 1, remote->pushurl_alloc);
 122        remote->pushurl[remote->pushurl_nr++] = pushurl;
 123}
 124
 125static void add_pushurl_alias(struct remote *remote, const char *url)
 126{
 127        const char *pushurl = alias_url(url, &rewrites_push);
 128        if (pushurl != url)
 129                add_pushurl(remote, pushurl);
 130}
 131
 132static void add_url_alias(struct remote *remote, const char *url)
 133{
 134        add_url(remote, alias_url(url, &rewrites));
 135        add_pushurl_alias(remote, url);
 136}
 137
 138static struct remote *make_remote(const char *name, int len)
 139{
 140        struct remote *ret;
 141        int i;
 142
 143        for (i = 0; i < remotes_nr; i++) {
 144                if (len ? (!strncmp(name, remotes[i]->name, len) &&
 145                           !remotes[i]->name[len]) :
 146                    !strcmp(name, remotes[i]->name))
 147                        return remotes[i];
 148        }
 149
 150        ret = xcalloc(1, sizeof(struct remote));
 151        ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 152        remotes[remotes_nr++] = ret;
 153        if (len)
 154                ret->name = xstrndup(name, len);
 155        else
 156                ret->name = xstrdup(name);
 157        return ret;
 158}
 159
 160static void add_merge(struct branch *branch, const char *name)
 161{
 162        ALLOC_GROW(branch->merge_name, branch->merge_nr + 1,
 163                   branch->merge_alloc);
 164        branch->merge_name[branch->merge_nr++] = name;
 165}
 166
 167static struct branch *make_branch(const char *name, int len)
 168{
 169        struct branch *ret;
 170        int i;
 171        char *refname;
 172
 173        for (i = 0; i < branches_nr; i++) {
 174                if (len ? (!strncmp(name, branches[i]->name, len) &&
 175                           !branches[i]->name[len]) :
 176                    !strcmp(name, branches[i]->name))
 177                        return branches[i];
 178        }
 179
 180        ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 181        ret = xcalloc(1, sizeof(struct branch));
 182        branches[branches_nr++] = ret;
 183        if (len)
 184                ret->name = xstrndup(name, len);
 185        else
 186                ret->name = xstrdup(name);
 187        refname = xmalloc(strlen(name) + strlen("refs/heads/") + 1);
 188        strcpy(refname, "refs/heads/");
 189        strcpy(refname + strlen("refs/heads/"), ret->name);
 190        ret->refname = refname;
 191
 192        return ret;
 193}
 194
 195static struct rewrite *make_rewrite(struct rewrites *r, const char *base, int len)
 196{
 197        struct rewrite *ret;
 198        int i;
 199
 200        for (i = 0; i < r->rewrite_nr; i++) {
 201                if (len
 202                    ? (len == r->rewrite[i]->baselen &&
 203                       !strncmp(base, r->rewrite[i]->base, len))
 204                    : !strcmp(base, r->rewrite[i]->base))
 205                        return r->rewrite[i];
 206        }
 207
 208        ALLOC_GROW(r->rewrite, r->rewrite_nr + 1, r->rewrite_alloc);
 209        ret = xcalloc(1, sizeof(struct rewrite));
 210        r->rewrite[r->rewrite_nr++] = ret;
 211        if (len) {
 212                ret->base = xstrndup(base, len);
 213                ret->baselen = len;
 214        }
 215        else {
 216                ret->base = xstrdup(base);
 217                ret->baselen = strlen(base);
 218        }
 219        return ret;
 220}
 221
 222static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 223{
 224        ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 225        rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 226        rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 227        rewrite->instead_of_nr++;
 228}
 229
 230static void read_remotes_file(struct remote *remote)
 231{
 232        FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
 233
 234        if (!f)
 235                return;
 236        remote->origin = REMOTE_REMOTES;
 237        while (fgets(buffer, BUF_SIZE, f)) {
 238                int value_list;
 239                char *s, *p;
 240
 241                if (!prefixcmp(buffer, "URL:")) {
 242                        value_list = 0;
 243                        s = buffer + 4;
 244                } else if (!prefixcmp(buffer, "Push:")) {
 245                        value_list = 1;
 246                        s = buffer + 5;
 247                } else if (!prefixcmp(buffer, "Pull:")) {
 248                        value_list = 2;
 249                        s = buffer + 5;
 250                } else
 251                        continue;
 252
 253                while (isspace(*s))
 254                        s++;
 255                if (!*s)
 256                        continue;
 257
 258                p = s + strlen(s);
 259                while (isspace(p[-1]))
 260                        *--p = 0;
 261
 262                switch (value_list) {
 263                case 0:
 264                        add_url_alias(remote, xstrdup(s));
 265                        break;
 266                case 1:
 267                        add_push_refspec(remote, xstrdup(s));
 268                        break;
 269                case 2:
 270                        add_fetch_refspec(remote, xstrdup(s));
 271                        break;
 272                }
 273        }
 274        fclose(f);
 275}
 276
 277static void read_branches_file(struct remote *remote)
 278{
 279        char *frag;
 280        struct strbuf branch = STRBUF_INIT;
 281        int n = 1000;
 282        FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 283        char *s, *p;
 284        int len;
 285
 286        if (!f)
 287                return;
 288        s = fgets(buffer, BUF_SIZE, f);
 289        fclose(f);
 290        if (!s)
 291                return;
 292        while (isspace(*s))
 293                s++;
 294        if (!*s)
 295                return;
 296        remote->origin = REMOTE_BRANCHES;
 297        p = s + strlen(s);
 298        while (isspace(p[-1]))
 299                *--p = 0;
 300        len = p - s;
 301        p = xmalloc(len + 1);
 302        strcpy(p, s);
 303
 304        /*
 305         * The branches file would have URL and optionally
 306         * #branch specified.  The "master" (or specified) branch is
 307         * fetched and stored in the local branch of the same name.
 308         */
 309        frag = strchr(p, '#');
 310        if (frag) {
 311                *(frag++) = '\0';
 312                strbuf_addf(&branch, "refs/heads/%s", frag);
 313        } else
 314                strbuf_addstr(&branch, "refs/heads/master");
 315
 316        strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 317        add_url_alias(remote, p);
 318        add_fetch_refspec(remote, strbuf_detach(&branch, NULL));
 319        /*
 320         * Cogito compatible push: push current HEAD to remote #branch
 321         * (master if missing)
 322         */
 323        strbuf_init(&branch, 0);
 324        strbuf_addstr(&branch, "HEAD");
 325        if (frag)
 326                strbuf_addf(&branch, ":refs/heads/%s", frag);
 327        else
 328                strbuf_addstr(&branch, ":refs/heads/master");
 329        add_push_refspec(remote, strbuf_detach(&branch, NULL));
 330        remote->fetch_tags = 1; /* always auto-follow */
 331}
 332
 333static int handle_config(const char *key, const char *value, void *cb)
 334{
 335        const char *name;
 336        const char *subkey;
 337        struct remote *remote;
 338        struct branch *branch;
 339        if (!prefixcmp(key, "branch.")) {
 340                name = key + 7;
 341                subkey = strrchr(name, '.');
 342                if (!subkey)
 343                        return 0;
 344                branch = make_branch(name, subkey - name);
 345                if (!strcmp(subkey, ".remote")) {
 346                        if (git_config_string(&branch->remote_name, key, value))
 347                                return -1;
 348                        if (branch == current_branch) {
 349                                default_remote_name = branch->remote_name;
 350                                explicit_default_remote_name = 1;
 351                        }
 352                } else if (!strcmp(subkey, ".pushremote")) {
 353                        if (branch == current_branch)
 354                                if (git_config_string(&pushremote_name, key, value))
 355                                        return -1;
 356                } else if (!strcmp(subkey, ".merge")) {
 357                        if (!value)
 358                                return config_error_nonbool(key);
 359                        add_merge(branch, xstrdup(value));
 360                }
 361                return 0;
 362        }
 363        if (!prefixcmp(key, "url.")) {
 364                struct rewrite *rewrite;
 365                name = key + 4;
 366                subkey = strrchr(name, '.');
 367                if (!subkey)
 368                        return 0;
 369                if (!strcmp(subkey, ".insteadof")) {
 370                        rewrite = make_rewrite(&rewrites, name, subkey - name);
 371                        if (!value)
 372                                return config_error_nonbool(key);
 373                        add_instead_of(rewrite, xstrdup(value));
 374                } else if (!strcmp(subkey, ".pushinsteadof")) {
 375                        rewrite = make_rewrite(&rewrites_push, name, subkey - name);
 376                        if (!value)
 377                                return config_error_nonbool(key);
 378                        add_instead_of(rewrite, xstrdup(value));
 379                }
 380        }
 381
 382        if (prefixcmp(key,  "remote."))
 383                return 0;
 384        name = key + 7;
 385
 386        /* Handle remote.* variables */
 387        if (!strcmp(name, "pushdefault"))
 388                return git_config_string(&pushremote_name, key, value);
 389
 390        /* Handle remote.<name>.* variables */
 391        if (*name == '/') {
 392                warning("Config remote shorthand cannot begin with '/': %s",
 393                        name);
 394                return 0;
 395        }
 396        subkey = strrchr(name, '.');
 397        if (!subkey)
 398                return 0;
 399        remote = make_remote(name, subkey - name);
 400        remote->origin = REMOTE_CONFIG;
 401        if (!strcmp(subkey, ".mirror"))
 402                remote->mirror = git_config_bool(key, value);
 403        else if (!strcmp(subkey, ".skipdefaultupdate"))
 404                remote->skip_default_update = git_config_bool(key, value);
 405        else if (!strcmp(subkey, ".skipfetchall"))
 406                remote->skip_default_update = git_config_bool(key, value);
 407        else if (!strcmp(subkey, ".url")) {
 408                const char *v;
 409                if (git_config_string(&v, key, value))
 410                        return -1;
 411                add_url(remote, v);
 412        } else if (!strcmp(subkey, ".pushurl")) {
 413                const char *v;
 414                if (git_config_string(&v, key, value))
 415                        return -1;
 416                add_pushurl(remote, v);
 417        } else if (!strcmp(subkey, ".push")) {
 418                const char *v;
 419                if (git_config_string(&v, key, value))
 420                        return -1;
 421                add_push_refspec(remote, v);
 422        } else if (!strcmp(subkey, ".fetch")) {
 423                const char *v;
 424                if (git_config_string(&v, key, value))
 425                        return -1;
 426                add_fetch_refspec(remote, v);
 427        } else if (!strcmp(subkey, ".receivepack")) {
 428                const char *v;
 429                if (git_config_string(&v, key, value))
 430                        return -1;
 431                if (!remote->receivepack)
 432                        remote->receivepack = v;
 433                else
 434                        error("more than one receivepack given, using the first");
 435        } else if (!strcmp(subkey, ".uploadpack")) {
 436                const char *v;
 437                if (git_config_string(&v, key, value))
 438                        return -1;
 439                if (!remote->uploadpack)
 440                        remote->uploadpack = v;
 441                else
 442                        error("more than one uploadpack given, using the first");
 443        } else if (!strcmp(subkey, ".tagopt")) {
 444                if (!strcmp(value, "--no-tags"))
 445                        remote->fetch_tags = -1;
 446                else if (!strcmp(value, "--tags"))
 447                        remote->fetch_tags = 2;
 448        } else if (!strcmp(subkey, ".proxy")) {
 449                return git_config_string((const char **)&remote->http_proxy,
 450                                         key, value);
 451        } else if (!strcmp(subkey, ".vcs")) {
 452                return git_config_string(&remote->foreign_vcs, key, value);
 453        }
 454        return 0;
 455}
 456
 457static void alias_all_urls(void)
 458{
 459        int i, j;
 460        for (i = 0; i < remotes_nr; i++) {
 461                int add_pushurl_aliases;
 462                if (!remotes[i])
 463                        continue;
 464                for (j = 0; j < remotes[i]->pushurl_nr; j++) {
 465                        remotes[i]->pushurl[j] = alias_url(remotes[i]->pushurl[j], &rewrites);
 466                }
 467                add_pushurl_aliases = remotes[i]->pushurl_nr == 0;
 468                for (j = 0; j < remotes[i]->url_nr; j++) {
 469                        if (add_pushurl_aliases)
 470                                add_pushurl_alias(remotes[i], remotes[i]->url[j]);
 471                        remotes[i]->url[j] = alias_url(remotes[i]->url[j], &rewrites);
 472                }
 473        }
 474}
 475
 476static void read_config(void)
 477{
 478        unsigned char sha1[20];
 479        const char *head_ref;
 480        int flag;
 481        if (default_remote_name) /* did this already */
 482                return;
 483        default_remote_name = xstrdup("origin");
 484        current_branch = NULL;
 485        head_ref = resolve_ref_unsafe("HEAD", sha1, 0, &flag);
 486        if (head_ref && (flag & REF_ISSYMREF) &&
 487            !prefixcmp(head_ref, "refs/heads/")) {
 488                current_branch =
 489                        make_branch(head_ref + strlen("refs/heads/"), 0);
 490        }
 491        git_config(handle_config, NULL);
 492        alias_all_urls();
 493}
 494
 495/*
 496 * This function frees a refspec array.
 497 * Warning: code paths should be checked to ensure that the src
 498 *          and dst pointers are always freeable pointers as well
 499 *          as the refspec pointer itself.
 500 */
 501static void free_refspecs(struct refspec *refspec, int nr_refspec)
 502{
 503        int i;
 504
 505        if (!refspec)
 506                return;
 507
 508        for (i = 0; i < nr_refspec; i++) {
 509                free(refspec[i].src);
 510                free(refspec[i].dst);
 511        }
 512        free(refspec);
 513}
 514
 515static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 516{
 517        int i;
 518        struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 519
 520        for (i = 0; i < nr_refspec; i++) {
 521                size_t llen;
 522                int is_glob;
 523                const char *lhs, *rhs;
 524                int flags;
 525
 526                is_glob = 0;
 527
 528                lhs = refspec[i];
 529                if (*lhs == '+') {
 530                        rs[i].force = 1;
 531                        lhs++;
 532                }
 533
 534                rhs = strrchr(lhs, ':');
 535
 536                /*
 537                 * Before going on, special case ":" (or "+:") as a refspec
 538                 * for pushing matching refs.
 539                 */
 540                if (!fetch && rhs == lhs && rhs[1] == '\0') {
 541                        rs[i].matching = 1;
 542                        continue;
 543                }
 544
 545                if (rhs) {
 546                        size_t rlen = strlen(++rhs);
 547                        is_glob = (1 <= rlen && strchr(rhs, '*'));
 548                        rs[i].dst = xstrndup(rhs, rlen);
 549                }
 550
 551                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 552                if (1 <= llen && memchr(lhs, '*', llen)) {
 553                        if ((rhs && !is_glob) || (!rhs && fetch))
 554                                goto invalid;
 555                        is_glob = 1;
 556                } else if (rhs && is_glob) {
 557                        goto invalid;
 558                }
 559
 560                rs[i].pattern = is_glob;
 561                rs[i].src = xstrndup(lhs, llen);
 562                flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 563
 564                if (fetch) {
 565                        unsigned char unused[40];
 566
 567                        /* LHS */
 568                        if (!*rs[i].src)
 569                                ; /* empty is ok; it means "HEAD" */
 570                        else if (llen == 40 && !get_sha1_hex(rs[i].src, unused))
 571                                rs[i].exact_sha1 = 1; /* ok */
 572                        else if (!check_refname_format(rs[i].src, flags))
 573                                ; /* valid looking ref is ok */
 574                        else
 575                                goto invalid;
 576                        /* RHS */
 577                        if (!rs[i].dst)
 578                                ; /* missing is ok; it is the same as empty */
 579                        else if (!*rs[i].dst)
 580                                ; /* empty is ok; it means "do not store" */
 581                        else if (!check_refname_format(rs[i].dst, flags))
 582                                ; /* valid looking ref is ok */
 583                        else
 584                                goto invalid;
 585                } else {
 586                        /*
 587                         * LHS
 588                         * - empty is allowed; it means delete.
 589                         * - when wildcarded, it must be a valid looking ref.
 590                         * - otherwise, it must be an extended SHA-1, but
 591                         *   there is no existing way to validate this.
 592                         */
 593                        if (!*rs[i].src)
 594                                ; /* empty is ok */
 595                        else if (is_glob) {
 596                                if (check_refname_format(rs[i].src, flags))
 597                                        goto invalid;
 598                        }
 599                        else
 600                                ; /* anything goes, for now */
 601                        /*
 602                         * RHS
 603                         * - missing is allowed, but LHS then must be a
 604                         *   valid looking ref.
 605                         * - empty is not allowed.
 606                         * - otherwise it must be a valid looking ref.
 607                         */
 608                        if (!rs[i].dst) {
 609                                if (check_refname_format(rs[i].src, flags))
 610                                        goto invalid;
 611                        } else if (!*rs[i].dst) {
 612                                goto invalid;
 613                        } else {
 614                                if (check_refname_format(rs[i].dst, flags))
 615                                        goto invalid;
 616                        }
 617                }
 618        }
 619        return rs;
 620
 621 invalid:
 622        if (verify) {
 623                /*
 624                 * nr_refspec must be greater than zero and i must be valid
 625                 * since it is only possible to reach this point from within
 626                 * the for loop above.
 627                 */
 628                free_refspecs(rs, i+1);
 629                return NULL;
 630        }
 631        die("Invalid refspec '%s'", refspec[i]);
 632}
 633
 634int valid_fetch_refspec(const char *fetch_refspec_str)
 635{
 636        struct refspec *refspec;
 637
 638        refspec = parse_refspec_internal(1, &fetch_refspec_str, 1, 1);
 639        free_refspecs(refspec, 1);
 640        return !!refspec;
 641}
 642
 643struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 644{
 645        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 646}
 647
 648static struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 649{
 650        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 651}
 652
 653void free_refspec(int nr_refspec, struct refspec *refspec)
 654{
 655        int i;
 656        for (i = 0; i < nr_refspec; i++) {
 657                free(refspec[i].src);
 658                free(refspec[i].dst);
 659        }
 660        free(refspec);
 661}
 662
 663static int valid_remote_nick(const char *name)
 664{
 665        if (!name[0] || is_dot_or_dotdot(name))
 666                return 0;
 667        return !strchr(name, '/'); /* no slash */
 668}
 669
 670static struct remote *remote_get_1(const char *name, const char *pushremote_name)
 671{
 672        struct remote *ret;
 673        int name_given = 0;
 674
 675        if (name)
 676                name_given = 1;
 677        else {
 678                if (pushremote_name) {
 679                        name = pushremote_name;
 680                        name_given = 1;
 681                } else {
 682                        name = default_remote_name;
 683                        name_given = explicit_default_remote_name;
 684                }
 685        }
 686
 687        ret = make_remote(name, 0);
 688        if (valid_remote_nick(name)) {
 689                if (!valid_remote(ret))
 690                        read_remotes_file(ret);
 691                if (!valid_remote(ret))
 692                        read_branches_file(ret);
 693        }
 694        if (name_given && !valid_remote(ret))
 695                add_url_alias(ret, name);
 696        if (!valid_remote(ret))
 697                return NULL;
 698        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 699        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 700        return ret;
 701}
 702
 703struct remote *remote_get(const char *name)
 704{
 705        read_config();
 706        return remote_get_1(name, NULL);
 707}
 708
 709struct remote *pushremote_get(const char *name)
 710{
 711        read_config();
 712        return remote_get_1(name, pushremote_name);
 713}
 714
 715int remote_is_configured(const char *name)
 716{
 717        int i;
 718        read_config();
 719
 720        for (i = 0; i < remotes_nr; i++)
 721                if (!strcmp(name, remotes[i]->name))
 722                        return 1;
 723        return 0;
 724}
 725
 726int for_each_remote(each_remote_fn fn, void *priv)
 727{
 728        int i, result = 0;
 729        read_config();
 730        for (i = 0; i < remotes_nr && !result; i++) {
 731                struct remote *r = remotes[i];
 732                if (!r)
 733                        continue;
 734                if (!r->fetch)
 735                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 736                                                       r->fetch_refspec);
 737                if (!r->push)
 738                        r->push = parse_push_refspec(r->push_refspec_nr,
 739                                                     r->push_refspec);
 740                result = fn(r, priv);
 741        }
 742        return result;
 743}
 744
 745void ref_remove_duplicates(struct ref *ref_map)
 746{
 747        struct string_list refs = STRING_LIST_INIT_NODUP;
 748        struct string_list_item *item = NULL;
 749        struct ref *prev = NULL, *next = NULL;
 750        for (; ref_map; prev = ref_map, ref_map = next) {
 751                next = ref_map->next;
 752                if (!ref_map->peer_ref)
 753                        continue;
 754
 755                item = string_list_lookup(&refs, ref_map->peer_ref->name);
 756                if (item) {
 757                        if (strcmp(((struct ref *)item->util)->name,
 758                                   ref_map->name))
 759                                die("%s tracks both %s and %s",
 760                                    ref_map->peer_ref->name,
 761                                    ((struct ref *)item->util)->name,
 762                                    ref_map->name);
 763                        prev->next = ref_map->next;
 764                        free(ref_map->peer_ref);
 765                        free(ref_map);
 766                        ref_map = prev; /* skip this; we freed it */
 767                        continue;
 768                }
 769
 770                item = string_list_insert(&refs, ref_map->peer_ref->name);
 771                item->util = ref_map;
 772        }
 773        string_list_clear(&refs, 0);
 774}
 775
 776int remote_has_url(struct remote *remote, const char *url)
 777{
 778        int i;
 779        for (i = 0; i < remote->url_nr; i++) {
 780                if (!strcmp(remote->url[i], url))
 781                        return 1;
 782        }
 783        return 0;
 784}
 785
 786static int match_name_with_pattern(const char *key, const char *name,
 787                                   const char *value, char **result)
 788{
 789        const char *kstar = strchr(key, '*');
 790        size_t klen;
 791        size_t ksuffixlen;
 792        size_t namelen;
 793        int ret;
 794        if (!kstar)
 795                die("Key '%s' of pattern had no '*'", key);
 796        klen = kstar - key;
 797        ksuffixlen = strlen(kstar + 1);
 798        namelen = strlen(name);
 799        ret = !strncmp(name, key, klen) && namelen >= klen + ksuffixlen &&
 800                !memcmp(name + namelen - ksuffixlen, kstar + 1, ksuffixlen);
 801        if (ret && value) {
 802                const char *vstar = strchr(value, '*');
 803                size_t vlen;
 804                size_t vsuffixlen;
 805                if (!vstar)
 806                        die("Value '%s' of pattern has no '*'", value);
 807                vlen = vstar - value;
 808                vsuffixlen = strlen(vstar + 1);
 809                *result = xmalloc(vlen + vsuffixlen +
 810                                  strlen(name) -
 811                                  klen - ksuffixlen + 1);
 812                strncpy(*result, value, vlen);
 813                strncpy(*result + vlen,
 814                        name + klen, namelen - klen - ksuffixlen);
 815                strcpy(*result + vlen + namelen - klen - ksuffixlen,
 816                       vstar + 1);
 817        }
 818        return ret;
 819}
 820
 821static int query_refspecs(struct refspec *refs, int ref_count, struct refspec *query)
 822{
 823        int i;
 824        int find_src = !query->src;
 825
 826        if (find_src && !query->dst)
 827                return error("query_refspecs: need either src or dst");
 828
 829        for (i = 0; i < ref_count; i++) {
 830                struct refspec *refspec = &refs[i];
 831                const char *key = find_src ? refspec->dst : refspec->src;
 832                const char *value = find_src ? refspec->src : refspec->dst;
 833                const char *needle = find_src ? query->dst : query->src;
 834                char **result = find_src ? &query->src : &query->dst;
 835
 836                if (!refspec->dst)
 837                        continue;
 838                if (refspec->pattern) {
 839                        if (match_name_with_pattern(key, needle, value, result)) {
 840                                query->force = refspec->force;
 841                                return 0;
 842                        }
 843                } else if (!strcmp(needle, key)) {
 844                        *result = xstrdup(value);
 845                        query->force = refspec->force;
 846                        return 0;
 847                }
 848        }
 849        return -1;
 850}
 851
 852char *apply_refspecs(struct refspec *refspecs, int nr_refspec,
 853                     const char *name)
 854{
 855        struct refspec query;
 856
 857        memset(&query, 0, sizeof(struct refspec));
 858        query.src = (char *)name;
 859
 860        if (query_refspecs(refspecs, nr_refspec, &query))
 861                return NULL;
 862
 863        return query.dst;
 864}
 865
 866int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 867{
 868        return query_refspecs(remote->fetch, remote->fetch_refspec_nr, refspec);
 869}
 870
 871static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 872                const char *name)
 873{
 874        size_t len = strlen(name);
 875        struct ref *ref = xcalloc(1, sizeof(struct ref) + prefixlen + len + 1);
 876        memcpy(ref->name, prefix, prefixlen);
 877        memcpy(ref->name + prefixlen, name, len);
 878        return ref;
 879}
 880
 881struct ref *alloc_ref(const char *name)
 882{
 883        return alloc_ref_with_prefix("", 0, name);
 884}
 885
 886struct ref *copy_ref(const struct ref *ref)
 887{
 888        struct ref *cpy;
 889        size_t len;
 890        if (!ref)
 891                return NULL;
 892        len = strlen(ref->name);
 893        cpy = xmalloc(sizeof(struct ref) + len + 1);
 894        memcpy(cpy, ref, sizeof(struct ref) + len + 1);
 895        cpy->next = NULL;
 896        cpy->symref = ref->symref ? xstrdup(ref->symref) : NULL;
 897        cpy->remote_status = ref->remote_status ? xstrdup(ref->remote_status) : NULL;
 898        cpy->peer_ref = copy_ref(ref->peer_ref);
 899        return cpy;
 900}
 901
 902struct ref *copy_ref_list(const struct ref *ref)
 903{
 904        struct ref *ret = NULL;
 905        struct ref **tail = &ret;
 906        while (ref) {
 907                *tail = copy_ref(ref);
 908                ref = ref->next;
 909                tail = &((*tail)->next);
 910        }
 911        return ret;
 912}
 913
 914static void free_ref(struct ref *ref)
 915{
 916        if (!ref)
 917                return;
 918        free_ref(ref->peer_ref);
 919        free(ref->remote_status);
 920        free(ref->symref);
 921        free(ref);
 922}
 923
 924void free_refs(struct ref *ref)
 925{
 926        struct ref *next;
 927        while (ref) {
 928                next = ref->next;
 929                free_ref(ref);
 930                ref = next;
 931        }
 932}
 933
 934int ref_compare_name(const void *va, const void *vb)
 935{
 936        const struct ref *a = va, *b = vb;
 937        return strcmp(a->name, b->name);
 938}
 939
 940static void *ref_list_get_next(const void *a)
 941{
 942        return ((const struct ref *)a)->next;
 943}
 944
 945static void ref_list_set_next(void *a, void *next)
 946{
 947        ((struct ref *)a)->next = next;
 948}
 949
 950void sort_ref_list(struct ref **l, int (*cmp)(const void *, const void *))
 951{
 952        *l = llist_mergesort(*l, ref_list_get_next, ref_list_set_next, cmp);
 953}
 954
 955static int count_refspec_match(const char *pattern,
 956                               struct ref *refs,
 957                               struct ref **matched_ref)
 958{
 959        int patlen = strlen(pattern);
 960        struct ref *matched_weak = NULL;
 961        struct ref *matched = NULL;
 962        int weak_match = 0;
 963        int match = 0;
 964
 965        for (weak_match = match = 0; refs; refs = refs->next) {
 966                char *name = refs->name;
 967                int namelen = strlen(name);
 968
 969                if (!refname_match(pattern, name, ref_rev_parse_rules))
 970                        continue;
 971
 972                /* A match is "weak" if it is with refs outside
 973                 * heads or tags, and did not specify the pattern
 974                 * in full (e.g. "refs/remotes/origin/master") or at
 975                 * least from the toplevel (e.g. "remotes/origin/master");
 976                 * otherwise "git push $URL master" would result in
 977                 * ambiguity between remotes/origin/master and heads/master
 978                 * at the remote site.
 979                 */
 980                if (namelen != patlen &&
 981                    patlen != namelen - 5 &&
 982                    prefixcmp(name, "refs/heads/") &&
 983                    prefixcmp(name, "refs/tags/")) {
 984                        /* We want to catch the case where only weak
 985                         * matches are found and there are multiple
 986                         * matches, and where more than one strong
 987                         * matches are found, as ambiguous.  One
 988                         * strong match with zero or more weak matches
 989                         * are acceptable as a unique match.
 990                         */
 991                        matched_weak = refs;
 992                        weak_match++;
 993                }
 994                else {
 995                        matched = refs;
 996                        match++;
 997                }
 998        }
 999        if (!matched) {
1000                *matched_ref = matched_weak;
1001                return weak_match;
1002        }
1003        else {
1004                *matched_ref = matched;
1005                return match;
1006        }
1007}
1008
1009static void tail_link_ref(struct ref *ref, struct ref ***tail)
1010{
1011        **tail = ref;
1012        while (ref->next)
1013                ref = ref->next;
1014        *tail = &ref->next;
1015}
1016
1017static struct ref *alloc_delete_ref(void)
1018{
1019        struct ref *ref = alloc_ref("(delete)");
1020        hashclr(ref->new_sha1);
1021        return ref;
1022}
1023
1024static struct ref *try_explicit_object_name(const char *name)
1025{
1026        unsigned char sha1[20];
1027        struct ref *ref;
1028
1029        if (!*name)
1030                return alloc_delete_ref();
1031        if (get_sha1(name, sha1))
1032                return NULL;
1033        ref = alloc_ref(name);
1034        hashcpy(ref->new_sha1, sha1);
1035        return ref;
1036}
1037
1038static struct ref *make_linked_ref(const char *name, struct ref ***tail)
1039{
1040        struct ref *ret = alloc_ref(name);
1041        tail_link_ref(ret, tail);
1042        return ret;
1043}
1044
1045static char *guess_ref(const char *name, struct ref *peer)
1046{
1047        struct strbuf buf = STRBUF_INIT;
1048        unsigned char sha1[20];
1049
1050        const char *r = resolve_ref_unsafe(peer->name, sha1, 1, NULL);
1051        if (!r)
1052                return NULL;
1053
1054        if (!prefixcmp(r, "refs/heads/"))
1055                strbuf_addstr(&buf, "refs/heads/");
1056        else if (!prefixcmp(r, "refs/tags/"))
1057                strbuf_addstr(&buf, "refs/tags/");
1058        else
1059                return NULL;
1060
1061        strbuf_addstr(&buf, name);
1062        return strbuf_detach(&buf, NULL);
1063}
1064
1065static int match_explicit(struct ref *src, struct ref *dst,
1066                          struct ref ***dst_tail,
1067                          struct refspec *rs)
1068{
1069        struct ref *matched_src, *matched_dst;
1070        int copy_src;
1071
1072        const char *dst_value = rs->dst;
1073        char *dst_guess;
1074
1075        if (rs->pattern || rs->matching)
1076                return 0;
1077
1078        matched_src = matched_dst = NULL;
1079        switch (count_refspec_match(rs->src, src, &matched_src)) {
1080        case 1:
1081                copy_src = 1;
1082                break;
1083        case 0:
1084                /* The source could be in the get_sha1() format
1085                 * not a reference name.  :refs/other is a
1086                 * way to delete 'other' ref at the remote end.
1087                 */
1088                matched_src = try_explicit_object_name(rs->src);
1089                if (!matched_src)
1090                        return error("src refspec %s does not match any.", rs->src);
1091                copy_src = 0;
1092                break;
1093        default:
1094                return error("src refspec %s matches more than one.", rs->src);
1095        }
1096
1097        if (!dst_value) {
1098                unsigned char sha1[20];
1099                int flag;
1100
1101                dst_value = resolve_ref_unsafe(matched_src->name, sha1, 1, &flag);
1102                if (!dst_value ||
1103                    ((flag & REF_ISSYMREF) &&
1104                     prefixcmp(dst_value, "refs/heads/")))
1105                        die("%s cannot be resolved to branch.",
1106                            matched_src->name);
1107        }
1108
1109        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
1110        case 1:
1111                break;
1112        case 0:
1113                if (!memcmp(dst_value, "refs/", 5))
1114                        matched_dst = make_linked_ref(dst_value, dst_tail);
1115                else if (is_null_sha1(matched_src->new_sha1))
1116                        error("unable to delete '%s': remote ref does not exist",
1117                              dst_value);
1118                else if ((dst_guess = guess_ref(dst_value, matched_src)))
1119                        matched_dst = make_linked_ref(dst_guess, dst_tail);
1120                else
1121                        error("unable to push to unqualified destination: %s\n"
1122                              "The destination refspec neither matches an "
1123                              "existing ref on the remote nor\n"
1124                              "begins with refs/, and we are unable to "
1125                              "guess a prefix based on the source ref.",
1126                              dst_value);
1127                break;
1128        default:
1129                matched_dst = NULL;
1130                error("dst refspec %s matches more than one.",
1131                      dst_value);
1132                break;
1133        }
1134        if (!matched_dst)
1135                return -1;
1136        if (matched_dst->peer_ref)
1137                return error("dst ref %s receives from more than one src.",
1138                      matched_dst->name);
1139        else {
1140                matched_dst->peer_ref = copy_src ? copy_ref(matched_src) : matched_src;
1141                matched_dst->force = rs->force;
1142        }
1143        return 0;
1144}
1145
1146static int match_explicit_refs(struct ref *src, struct ref *dst,
1147                               struct ref ***dst_tail, struct refspec *rs,
1148                               int rs_nr)
1149{
1150        int i, errs;
1151        for (i = errs = 0; i < rs_nr; i++)
1152                errs += match_explicit(src, dst, dst_tail, &rs[i]);
1153        return errs;
1154}
1155
1156static char *get_ref_match(const struct refspec *rs, int rs_nr, const struct ref *ref,
1157                int send_mirror, int direction, const struct refspec **ret_pat)
1158{
1159        const struct refspec *pat;
1160        char *name;
1161        int i;
1162        int matching_refs = -1;
1163        for (i = 0; i < rs_nr; i++) {
1164                if (rs[i].matching &&
1165                    (matching_refs == -1 || rs[i].force)) {
1166                        matching_refs = i;
1167                        continue;
1168                }
1169
1170                if (rs[i].pattern) {
1171                        const char *dst_side = rs[i].dst ? rs[i].dst : rs[i].src;
1172                        int match;
1173                        if (direction == FROM_SRC)
1174                                match = match_name_with_pattern(rs[i].src, ref->name, dst_side, &name);
1175                        else
1176                                match = match_name_with_pattern(dst_side, ref->name, rs[i].src, &name);
1177                        if (match) {
1178                                matching_refs = i;
1179                                break;
1180                        }
1181                }
1182        }
1183        if (matching_refs == -1)
1184                return NULL;
1185
1186        pat = rs + matching_refs;
1187        if (pat->matching) {
1188                /*
1189                 * "matching refs"; traditionally we pushed everything
1190                 * including refs outside refs/heads/ hierarchy, but
1191                 * that does not make much sense these days.
1192                 */
1193                if (!send_mirror && prefixcmp(ref->name, "refs/heads/"))
1194                        return NULL;
1195                name = xstrdup(ref->name);
1196        }
1197        if (ret_pat)
1198                *ret_pat = pat;
1199        return name;
1200}
1201
1202static struct ref **tail_ref(struct ref **head)
1203{
1204        struct ref **tail = head;
1205        while (*tail)
1206                tail = &((*tail)->next);
1207        return tail;
1208}
1209
1210struct tips {
1211        struct commit **tip;
1212        int nr, alloc;
1213};
1214
1215static void add_to_tips(struct tips *tips, const unsigned char *sha1)
1216{
1217        struct commit *commit;
1218
1219        if (is_null_sha1(sha1))
1220                return;
1221        commit = lookup_commit_reference_gently(sha1, 1);
1222        if (!commit || (commit->object.flags & TMP_MARK))
1223                return;
1224        commit->object.flags |= TMP_MARK;
1225        ALLOC_GROW(tips->tip, tips->nr + 1, tips->alloc);
1226        tips->tip[tips->nr++] = commit;
1227}
1228
1229static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***dst_tail)
1230{
1231        struct string_list dst_tag = STRING_LIST_INIT_NODUP;
1232        struct string_list src_tag = STRING_LIST_INIT_NODUP;
1233        struct string_list_item *item;
1234        struct ref *ref;
1235        struct tips sent_tips;
1236
1237        /*
1238         * Collect everything we know they would have at the end of
1239         * this push, and collect all tags they have.
1240         */
1241        memset(&sent_tips, 0, sizeof(sent_tips));
1242        for (ref = *dst; ref; ref = ref->next) {
1243                if (ref->peer_ref &&
1244                    !is_null_sha1(ref->peer_ref->new_sha1))
1245                        add_to_tips(&sent_tips, ref->peer_ref->new_sha1);
1246                else
1247                        add_to_tips(&sent_tips, ref->old_sha1);
1248                if (!prefixcmp(ref->name, "refs/tags/"))
1249                        string_list_append(&dst_tag, ref->name);
1250        }
1251        clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
1252
1253        sort_string_list(&dst_tag);
1254
1255        /* Collect tags they do not have. */
1256        for (ref = src; ref; ref = ref->next) {
1257                if (prefixcmp(ref->name, "refs/tags/"))
1258                        continue; /* not a tag */
1259                if (string_list_has_string(&dst_tag, ref->name))
1260                        continue; /* they already have it */
1261                if (sha1_object_info(ref->new_sha1, NULL) != OBJ_TAG)
1262                        continue; /* be conservative */
1263                item = string_list_append(&src_tag, ref->name);
1264                item->util = ref;
1265        }
1266        string_list_clear(&dst_tag, 0);
1267
1268        /*
1269         * At this point, src_tag lists tags that are missing from
1270         * dst, and sent_tips lists the tips we are pushing or those
1271         * that we know they already have. An element in the src_tag
1272         * that is an ancestor of any of the sent_tips needs to be
1273         * sent to the other side.
1274         */
1275        if (sent_tips.nr) {
1276                for_each_string_list_item(item, &src_tag) {
1277                        struct ref *ref = item->util;
1278                        struct ref *dst_ref;
1279                        struct commit *commit;
1280
1281                        if (is_null_sha1(ref->new_sha1))
1282                                continue;
1283                        commit = lookup_commit_reference_gently(ref->new_sha1, 1);
1284                        if (!commit)
1285                                /* not pushing a commit, which is not an error */
1286                                continue;
1287
1288                        /*
1289                         * Is this tag, which they do not have, reachable from
1290                         * any of the commits we are sending?
1291                         */
1292                        if (!in_merge_bases_many(commit, sent_tips.nr, sent_tips.tip))
1293                                continue;
1294
1295                        /* Add it in */
1296                        dst_ref = make_linked_ref(ref->name, dst_tail);
1297                        hashcpy(dst_ref->new_sha1, ref->new_sha1);
1298                        dst_ref->peer_ref = copy_ref(ref);
1299                }
1300        }
1301        string_list_clear(&src_tag, 0);
1302        free(sent_tips.tip);
1303}
1304
1305struct ref *find_ref_by_name(const struct ref *list, const char *name)
1306{
1307        for ( ; list; list = list->next)
1308                if (!strcmp(list->name, name))
1309                        return (struct ref *)list;
1310        return NULL;
1311}
1312
1313/*
1314 * Given the set of refs the local repository has, the set of refs the
1315 * remote repository has, and the refspec used for push, determine
1316 * what remote refs we will update and with what value by setting
1317 * peer_ref (which object is being pushed) and force (if the push is
1318 * forced) in elements of "dst". The function may add new elements to
1319 * dst (e.g. pushing to a new branch, done in match_explicit_refs).
1320 */
1321int match_push_refs(struct ref *src, struct ref **dst,
1322                    int nr_refspec, const char **refspec, int flags)
1323{
1324        struct refspec *rs;
1325        int send_all = flags & MATCH_REFS_ALL;
1326        int send_mirror = flags & MATCH_REFS_MIRROR;
1327        int send_prune = flags & MATCH_REFS_PRUNE;
1328        int errs;
1329        static const char *default_refspec[] = { ":", NULL };
1330        struct ref *ref, **dst_tail = tail_ref(dst);
1331
1332        if (!nr_refspec) {
1333                nr_refspec = 1;
1334                refspec = default_refspec;
1335        }
1336        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1337        errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
1338
1339        /* pick the remainder */
1340        for (ref = src; ref; ref = ref->next) {
1341                struct ref *dst_peer;
1342                const struct refspec *pat = NULL;
1343                char *dst_name;
1344
1345                dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
1346                if (!dst_name)
1347                        continue;
1348
1349                dst_peer = find_ref_by_name(*dst, dst_name);
1350                if (dst_peer) {
1351                        if (dst_peer->peer_ref)
1352                                /* We're already sending something to this ref. */
1353                                goto free_name;
1354                } else {
1355                        if (pat->matching && !(send_all || send_mirror))
1356                                /*
1357                                 * Remote doesn't have it, and we have no
1358                                 * explicit pattern, and we don't have
1359                                 * --all nor --mirror.
1360                                 */
1361                                goto free_name;
1362
1363                        /* Create a new one and link it */
1364                        dst_peer = make_linked_ref(dst_name, &dst_tail);
1365                        hashcpy(dst_peer->new_sha1, ref->new_sha1);
1366                }
1367                dst_peer->peer_ref = copy_ref(ref);
1368                dst_peer->force = pat->force;
1369        free_name:
1370                free(dst_name);
1371        }
1372
1373        if (flags & MATCH_REFS_FOLLOW_TAGS)
1374                add_missing_tags(src, dst, &dst_tail);
1375
1376        if (send_prune) {
1377                /* check for missing refs on the remote */
1378                for (ref = *dst; ref; ref = ref->next) {
1379                        char *src_name;
1380
1381                        if (ref->peer_ref)
1382                                /* We're already sending something to this ref. */
1383                                continue;
1384
1385                        src_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_DST, NULL);
1386                        if (src_name) {
1387                                if (!find_ref_by_name(src, src_name))
1388                                        ref->peer_ref = alloc_delete_ref();
1389                                free(src_name);
1390                        }
1391                }
1392        }
1393        if (errs)
1394                return -1;
1395        return 0;
1396}
1397
1398void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
1399                             int force_update)
1400{
1401        struct ref *ref;
1402
1403        for (ref = remote_refs; ref; ref = ref->next) {
1404                int force_ref_update = ref->force || force_update;
1405                int reject_reason = 0;
1406
1407                if (ref->peer_ref)
1408                        hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
1409                else if (!send_mirror)
1410                        continue;
1411
1412                ref->deletion = is_null_sha1(ref->new_sha1);
1413                if (!ref->deletion &&
1414                        !hashcmp(ref->old_sha1, ref->new_sha1)) {
1415                        ref->status = REF_STATUS_UPTODATE;
1416                        continue;
1417                }
1418
1419                /*
1420                 * Bypass the usual "must fast-forward" check but
1421                 * replace it with a weaker "the old value must be
1422                 * this value we observed".  If the remote ref has
1423                 * moved and is now different from what we expect,
1424                 * reject any push.
1425                 *
1426                 * It also is an error if the user told us to check
1427                 * with the remote-tracking branch to find the value
1428                 * to expect, but we did not have such a tracking
1429                 * branch.
1430                 */
1431                if (ref->expect_old_sha1) {
1432                        if (ref->expect_old_no_trackback ||
1433                            hashcmp(ref->old_sha1, ref->old_sha1_expect))
1434                                reject_reason = REF_STATUS_REJECT_STALE;
1435                }
1436
1437                /*
1438                 * The usual "must fast-forward" rules.
1439                 *
1440                 * Decide whether an individual refspec A:B can be
1441                 * pushed.  The push will succeed if any of the
1442                 * following are true:
1443                 *
1444                 * (1) the remote reference B does not exist
1445                 *
1446                 * (2) the remote reference B is being removed (i.e.,
1447                 *     pushing :B where no source is specified)
1448                 *
1449                 * (3) the destination is not under refs/tags/, and
1450                 *     if the old and new value is a commit, the new
1451                 *     is a descendant of the old.
1452                 *
1453                 * (4) it is forced using the +A:B notation, or by
1454                 *     passing the --force argument
1455                 */
1456
1457                else if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
1458                        if (!prefixcmp(ref->name, "refs/tags/"))
1459                                reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
1460                        else if (!has_sha1_file(ref->old_sha1))
1461                                reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
1462                        else if (!lookup_commit_reference_gently(ref->old_sha1, 1) ||
1463                                 !lookup_commit_reference_gently(ref->new_sha1, 1))
1464                                reject_reason = REF_STATUS_REJECT_NEEDS_FORCE;
1465                        else if (!ref_newer(ref->new_sha1, ref->old_sha1))
1466                                reject_reason = REF_STATUS_REJECT_NONFASTFORWARD;
1467                }
1468
1469                /*
1470                 * "--force" will defeat any rejection implemented
1471                 * by the rules above.
1472                 */
1473                if (!force_ref_update)
1474                        ref->status = reject_reason;
1475                else if (reject_reason)
1476                        ref->forced_update = 1;
1477        }
1478}
1479
1480struct branch *branch_get(const char *name)
1481{
1482        struct branch *ret;
1483
1484        read_config();
1485        if (!name || !*name || !strcmp(name, "HEAD"))
1486                ret = current_branch;
1487        else
1488                ret = make_branch(name, 0);
1489        if (ret && ret->remote_name) {
1490                ret->remote = remote_get(ret->remote_name);
1491                if (ret->merge_nr) {
1492                        int i;
1493                        ret->merge = xcalloc(ret->merge_nr, sizeof(*ret->merge));
1494                        for (i = 0; i < ret->merge_nr; i++) {
1495                                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1496                                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1497                                if (remote_find_tracking(ret->remote, ret->merge[i])
1498                                    && !strcmp(ret->remote_name, "."))
1499                                        ret->merge[i]->dst = xstrdup(ret->merge_name[i]);
1500                        }
1501                }
1502        }
1503        return ret;
1504}
1505
1506int branch_has_merge_config(struct branch *branch)
1507{
1508        return branch && !!branch->merge;
1509}
1510
1511int branch_merge_matches(struct branch *branch,
1512                                 int i,
1513                                 const char *refname)
1514{
1515        if (!branch || i < 0 || i >= branch->merge_nr)
1516                return 0;
1517        return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
1518}
1519
1520static int ignore_symref_update(const char *refname)
1521{
1522        unsigned char sha1[20];
1523        int flag;
1524
1525        if (!resolve_ref_unsafe(refname, sha1, 0, &flag))
1526                return 0; /* non-existing refs are OK */
1527        return (flag & REF_ISSYMREF);
1528}
1529
1530static struct ref *get_expanded_map(const struct ref *remote_refs,
1531                                    const struct refspec *refspec)
1532{
1533        const struct ref *ref;
1534        struct ref *ret = NULL;
1535        struct ref **tail = &ret;
1536
1537        char *expn_name;
1538
1539        for (ref = remote_refs; ref; ref = ref->next) {
1540                if (strchr(ref->name, '^'))
1541                        continue; /* a dereference item */
1542                if (match_name_with_pattern(refspec->src, ref->name,
1543                                            refspec->dst, &expn_name) &&
1544                    !ignore_symref_update(expn_name)) {
1545                        struct ref *cpy = copy_ref(ref);
1546
1547                        cpy->peer_ref = alloc_ref(expn_name);
1548                        free(expn_name);
1549                        if (refspec->force)
1550                                cpy->peer_ref->force = 1;
1551                        *tail = cpy;
1552                        tail = &cpy->next;
1553                }
1554        }
1555
1556        return ret;
1557}
1558
1559static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1560{
1561        const struct ref *ref;
1562        for (ref = refs; ref; ref = ref->next) {
1563                if (refname_match(name, ref->name, ref_fetch_rules))
1564                        return ref;
1565        }
1566        return NULL;
1567}
1568
1569struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1570{
1571        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1572
1573        if (!ref)
1574                return NULL;
1575
1576        return copy_ref(ref);
1577}
1578
1579static struct ref *get_local_ref(const char *name)
1580{
1581        if (!name || name[0] == '\0')
1582                return NULL;
1583
1584        if (!prefixcmp(name, "refs/"))
1585                return alloc_ref(name);
1586
1587        if (!prefixcmp(name, "heads/") ||
1588            !prefixcmp(name, "tags/") ||
1589            !prefixcmp(name, "remotes/"))
1590                return alloc_ref_with_prefix("refs/", 5, name);
1591
1592        return alloc_ref_with_prefix("refs/heads/", 11, name);
1593}
1594
1595int get_fetch_map(const struct ref *remote_refs,
1596                  const struct refspec *refspec,
1597                  struct ref ***tail,
1598                  int missing_ok)
1599{
1600        struct ref *ref_map, **rmp;
1601
1602        if (refspec->pattern) {
1603                ref_map = get_expanded_map(remote_refs, refspec);
1604        } else {
1605                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1606
1607                if (refspec->exact_sha1) {
1608                        ref_map = alloc_ref(name);
1609                        get_sha1_hex(name, ref_map->old_sha1);
1610                } else {
1611                        ref_map = get_remote_ref(remote_refs, name);
1612                }
1613                if (!missing_ok && !ref_map)
1614                        die("Couldn't find remote ref %s", name);
1615                if (ref_map) {
1616                        ref_map->peer_ref = get_local_ref(refspec->dst);
1617                        if (ref_map->peer_ref && refspec->force)
1618                                ref_map->peer_ref->force = 1;
1619                }
1620        }
1621
1622        for (rmp = &ref_map; *rmp; ) {
1623                if ((*rmp)->peer_ref) {
1624                        if (prefixcmp((*rmp)->peer_ref->name, "refs/") ||
1625                            check_refname_format((*rmp)->peer_ref->name, 0)) {
1626                                struct ref *ignore = *rmp;
1627                                error("* Ignoring funny ref '%s' locally",
1628                                      (*rmp)->peer_ref->name);
1629                                *rmp = (*rmp)->next;
1630                                free(ignore->peer_ref);
1631                                free(ignore);
1632                                continue;
1633                        }
1634                }
1635                rmp = &((*rmp)->next);
1636        }
1637
1638        if (ref_map)
1639                tail_link_ref(ref_map, tail);
1640
1641        return 0;
1642}
1643
1644int resolve_remote_symref(struct ref *ref, struct ref *list)
1645{
1646        if (!ref->symref)
1647                return 0;
1648        for (; list; list = list->next)
1649                if (!strcmp(ref->symref, list->name)) {
1650                        hashcpy(ref->old_sha1, list->old_sha1);
1651                        return 0;
1652                }
1653        return 1;
1654}
1655
1656static void unmark_and_free(struct commit_list *list, unsigned int mark)
1657{
1658        while (list) {
1659                struct commit_list *temp = list;
1660                temp->item->object.flags &= ~mark;
1661                list = temp->next;
1662                free(temp);
1663        }
1664}
1665
1666int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
1667{
1668        struct object *o;
1669        struct commit *old, *new;
1670        struct commit_list *list, *used;
1671        int found = 0;
1672
1673        /*
1674         * Both new and old must be commit-ish and new is descendant of
1675         * old.  Otherwise we require --force.
1676         */
1677        o = deref_tag(parse_object(old_sha1), NULL, 0);
1678        if (!o || o->type != OBJ_COMMIT)
1679                return 0;
1680        old = (struct commit *) o;
1681
1682        o = deref_tag(parse_object(new_sha1), NULL, 0);
1683        if (!o || o->type != OBJ_COMMIT)
1684                return 0;
1685        new = (struct commit *) o;
1686
1687        if (parse_commit(new) < 0)
1688                return 0;
1689
1690        used = list = NULL;
1691        commit_list_insert(new, &list);
1692        while (list) {
1693                new = pop_most_recent_commit(&list, TMP_MARK);
1694                commit_list_insert(new, &used);
1695                if (new == old) {
1696                        found = 1;
1697                        break;
1698                }
1699        }
1700        unmark_and_free(list, TMP_MARK);
1701        unmark_and_free(used, TMP_MARK);
1702        return found;
1703}
1704
1705/*
1706 * Return true if there is anything to report, otherwise false.
1707 */
1708int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
1709{
1710        unsigned char sha1[20];
1711        struct commit *ours, *theirs;
1712        char symmetric[84];
1713        struct rev_info revs;
1714        const char *rev_argv[10], *base;
1715        int rev_argc;
1716
1717        /*
1718         * Nothing to report unless we are marked to build on top of
1719         * somebody else.
1720         */
1721        if (!branch ||
1722            !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
1723                return 0;
1724
1725        /*
1726         * If what we used to build on no longer exists, there is
1727         * nothing to report.
1728         */
1729        base = branch->merge[0]->dst;
1730        if (read_ref(base, sha1))
1731                return 0;
1732        theirs = lookup_commit_reference(sha1);
1733        if (!theirs)
1734                return 0;
1735
1736        if (read_ref(branch->refname, sha1))
1737                return 0;
1738        ours = lookup_commit_reference(sha1);
1739        if (!ours)
1740                return 0;
1741
1742        /* are we the same? */
1743        if (theirs == ours)
1744                return 0;
1745
1746        /* Run "rev-list --left-right ours...theirs" internally... */
1747        rev_argc = 0;
1748        rev_argv[rev_argc++] = NULL;
1749        rev_argv[rev_argc++] = "--left-right";
1750        rev_argv[rev_argc++] = symmetric;
1751        rev_argv[rev_argc++] = "--";
1752        rev_argv[rev_argc] = NULL;
1753
1754        strcpy(symmetric, sha1_to_hex(ours->object.sha1));
1755        strcpy(symmetric + 40, "...");
1756        strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
1757
1758        init_revisions(&revs, NULL);
1759        setup_revisions(rev_argc, rev_argv, &revs, NULL);
1760        prepare_revision_walk(&revs);
1761
1762        /* ... and count the commits on each side. */
1763        *num_ours = 0;
1764        *num_theirs = 0;
1765        while (1) {
1766                struct commit *c = get_revision(&revs);
1767                if (!c)
1768                        break;
1769                if (c->object.flags & SYMMETRIC_LEFT)
1770                        (*num_ours)++;
1771                else
1772                        (*num_theirs)++;
1773        }
1774
1775        /* clear object flags smudged by the above traversal */
1776        clear_commit_marks(ours, ALL_REV_FLAGS);
1777        clear_commit_marks(theirs, ALL_REV_FLAGS);
1778        return 1;
1779}
1780
1781/*
1782 * Return true when there is anything to report, otherwise false.
1783 */
1784int format_tracking_info(struct branch *branch, struct strbuf *sb)
1785{
1786        int num_ours, num_theirs;
1787        const char *base;
1788
1789        if (!stat_tracking_info(branch, &num_ours, &num_theirs))
1790                return 0;
1791
1792        base = branch->merge[0]->dst;
1793        base = shorten_unambiguous_ref(base, 0);
1794        if (!num_theirs) {
1795                strbuf_addf(sb,
1796                        Q_("Your branch is ahead of '%s' by %d commit.\n",
1797                           "Your branch is ahead of '%s' by %d commits.\n",
1798                           num_ours),
1799                        base, num_ours);
1800                if (advice_status_hints)
1801                        strbuf_addf(sb,
1802                                _("  (use \"git push\" to publish your local commits)\n"));
1803        } else if (!num_ours) {
1804                strbuf_addf(sb,
1805                        Q_("Your branch is behind '%s' by %d commit, "
1806                               "and can be fast-forwarded.\n",
1807                           "Your branch is behind '%s' by %d commits, "
1808                               "and can be fast-forwarded.\n",
1809                           num_theirs),
1810                        base, num_theirs);
1811                if (advice_status_hints)
1812                        strbuf_addf(sb,
1813                                _("  (use \"git pull\" to update your local branch)\n"));
1814        } else {
1815                strbuf_addf(sb,
1816                        Q_("Your branch and '%s' have diverged,\n"
1817                               "and have %d and %d different commit each, "
1818                               "respectively.\n",
1819                           "Your branch and '%s' have diverged,\n"
1820                               "and have %d and %d different commits each, "
1821                               "respectively.\n",
1822                           num_theirs),
1823                        base, num_ours, num_theirs);
1824                if (advice_status_hints)
1825                        strbuf_addf(sb,
1826                                _("  (use \"git pull\" to merge the remote branch into yours)\n"));
1827        }
1828        return 1;
1829}
1830
1831static int one_local_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
1832{
1833        struct ref ***local_tail = cb_data;
1834        struct ref *ref;
1835        int len;
1836
1837        /* we already know it starts with refs/ to get here */
1838        if (check_refname_format(refname + 5, 0))
1839                return 0;
1840
1841        len = strlen(refname) + 1;
1842        ref = xcalloc(1, sizeof(*ref) + len);
1843        hashcpy(ref->new_sha1, sha1);
1844        memcpy(ref->name, refname, len);
1845        **local_tail = ref;
1846        *local_tail = &ref->next;
1847        return 0;
1848}
1849
1850struct ref *get_local_heads(void)
1851{
1852        struct ref *local_refs = NULL, **local_tail = &local_refs;
1853        for_each_ref(one_local_ref, &local_tail);
1854        return local_refs;
1855}
1856
1857struct ref *guess_remote_head(const struct ref *head,
1858                              const struct ref *refs,
1859                              int all)
1860{
1861        const struct ref *r;
1862        struct ref *list = NULL;
1863        struct ref **tail = &list;
1864
1865        if (!head)
1866                return NULL;
1867
1868        /*
1869         * Some transports support directly peeking at
1870         * where HEAD points; if that is the case, then
1871         * we don't have to guess.
1872         */
1873        if (head->symref)
1874                return copy_ref(find_ref_by_name(refs, head->symref));
1875
1876        /* If refs/heads/master could be right, it is. */
1877        if (!all) {
1878                r = find_ref_by_name(refs, "refs/heads/master");
1879                if (r && !hashcmp(r->old_sha1, head->old_sha1))
1880                        return copy_ref(r);
1881        }
1882
1883        /* Look for another ref that points there */
1884        for (r = refs; r; r = r->next) {
1885                if (r != head &&
1886                    !prefixcmp(r->name, "refs/heads/") &&
1887                    !hashcmp(r->old_sha1, head->old_sha1)) {
1888                        *tail = copy_ref(r);
1889                        tail = &((*tail)->next);
1890                        if (!all)
1891                                break;
1892                }
1893        }
1894
1895        return list;
1896}
1897
1898struct stale_heads_info {
1899        struct string_list *ref_names;
1900        struct ref **stale_refs_tail;
1901        struct refspec *refs;
1902        int ref_count;
1903};
1904
1905static int get_stale_heads_cb(const char *refname,
1906        const unsigned char *sha1, int flags, void *cb_data)
1907{
1908        struct stale_heads_info *info = cb_data;
1909        struct refspec query;
1910        memset(&query, 0, sizeof(struct refspec));
1911        query.dst = (char *)refname;
1912
1913        if (query_refspecs(info->refs, info->ref_count, &query))
1914                return 0; /* No matches */
1915
1916        /*
1917         * If we did find a suitable refspec and it's not a symref and
1918         * it's not in the list of refs that currently exist in that
1919         * remote we consider it to be stale.
1920         */
1921        if (!((flags & REF_ISSYMREF) ||
1922              string_list_has_string(info->ref_names, query.src))) {
1923                struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
1924                hashcpy(ref->new_sha1, sha1);
1925        }
1926
1927        free(query.src);
1928        return 0;
1929}
1930
1931struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fetch_map)
1932{
1933        struct ref *ref, *stale_refs = NULL;
1934        struct string_list ref_names = STRING_LIST_INIT_NODUP;
1935        struct stale_heads_info info;
1936        info.ref_names = &ref_names;
1937        info.stale_refs_tail = &stale_refs;
1938        info.refs = refs;
1939        info.ref_count = ref_count;
1940        for (ref = fetch_map; ref; ref = ref->next)
1941                string_list_append(&ref_names, ref->name);
1942        sort_string_list(&ref_names);
1943        for_each_ref(get_stale_heads_cb, &info);
1944        string_list_clear(&ref_names, 0);
1945        return stale_refs;
1946}
1947
1948/*
1949 * Compare-and-swap
1950 */
1951void clear_cas_option(struct push_cas_option *cas)
1952{
1953        int i;
1954
1955        for (i = 0; i < cas->nr; i++)
1956                free(cas->entry[i].refname);
1957        free(cas->entry);
1958        memset(cas, 0, sizeof(*cas));
1959}
1960
1961static struct push_cas *add_cas_entry(struct push_cas_option *cas,
1962                                      const char *refname,
1963                                      size_t refnamelen)
1964{
1965        struct push_cas *entry;
1966        ALLOC_GROW(cas->entry, cas->nr + 1, cas->alloc);
1967        entry = &cas->entry[cas->nr++];
1968        memset(entry, 0, sizeof(*entry));
1969        entry->refname = xmemdupz(refname, refnamelen);
1970        return entry;
1971}
1972
1973int parse_push_cas_option(struct push_cas_option *cas, const char *arg, int unset)
1974{
1975        const char *colon;
1976        struct push_cas *entry;
1977
1978        if (unset) {
1979                /* "--no-<option>" */
1980                clear_cas_option(cas);
1981                return 0;
1982        }
1983
1984        if (!arg) {
1985                /* just "--<option>" */
1986                cas->use_tracking_for_rest = 1;
1987                return 0;
1988        }
1989
1990        /* "--<option>=refname" or "--<option>=refname:value" */
1991        colon = strchrnul(arg, ':');
1992        entry = add_cas_entry(cas, arg, colon - arg);
1993        if (!*colon)
1994                entry->use_tracking = 1;
1995        else if (get_sha1(colon + 1, entry->expect))
1996                return error("cannot parse expected object name '%s'", colon + 1);
1997        return 0;
1998}
1999
2000int parseopt_push_cas_option(const struct option *opt, const char *arg, int unset)
2001{
2002        return parse_push_cas_option(opt->value, arg, unset);
2003}
2004
2005int is_empty_cas(const struct push_cas_option *cas)
2006{
2007        return !cas->use_tracking_for_rest && !cas->nr;
2008}
2009
2010/*
2011 * Look at remote.fetch refspec and see if we have a remote
2012 * tracking branch for the refname there.  Fill its current
2013 * value in sha1[].
2014 * If we cannot do so, return negative to signal an error.
2015 */
2016static int remote_tracking(struct remote *remote, const char *refname,
2017                           unsigned char sha1[20])
2018{
2019        char *dst;
2020
2021        dst = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
2022        if (!dst)
2023                return -1; /* no tracking ref for refname at remote */
2024        if (read_ref(dst, sha1))
2025                return -1; /* we know what the tracking ref is but we cannot read it */
2026        return 0;
2027}
2028
2029static void apply_cas(struct push_cas_option *cas,
2030                      struct remote *remote,
2031                      struct ref *ref)
2032{
2033        int i;
2034
2035        /* Find an explicit --<option>=<name>[:<value>] entry */
2036        for (i = 0; i < cas->nr; i++) {
2037                struct push_cas *entry = &cas->entry[i];
2038                if (!refname_match(entry->refname, ref->name, ref_rev_parse_rules))
2039                        continue;
2040                ref->expect_old_sha1 = 1;
2041                if (!entry->use_tracking)
2042                        hashcpy(ref->old_sha1_expect, cas->entry[i].expect);
2043                else if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2044                        ref->expect_old_no_trackback = 1;
2045                return;
2046        }
2047
2048        /* Are we using "--<option>" to cover all? */
2049        if (!cas->use_tracking_for_rest)
2050                return;
2051
2052        ref->expect_old_sha1 = 1;
2053        if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2054                ref->expect_old_no_trackback = 1;
2055}
2056
2057void apply_push_cas(struct push_cas_option *cas,
2058                    struct remote *remote,
2059                    struct ref *remote_refs)
2060{
2061        struct ref *ref;
2062        for (ref = remote_refs; ref; ref = ref->next)
2063                apply_cas(cas, remote, ref);
2064}