remote.con commit Merge branch 'fc/untracked-zsh-prompt' (741917f)
   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        const char *slash = strchr(remote->name, '/');
 280        char *frag;
 281        struct strbuf branch = STRBUF_INIT;
 282        int n = slash ? slash - remote->name : 1000;
 283        FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 284        char *s, *p;
 285        int len;
 286
 287        if (!f)
 288                return;
 289        s = fgets(buffer, BUF_SIZE, f);
 290        fclose(f);
 291        if (!s)
 292                return;
 293        while (isspace(*s))
 294                s++;
 295        if (!*s)
 296                return;
 297        remote->origin = REMOTE_BRANCHES;
 298        p = s + strlen(s);
 299        while (isspace(p[-1]))
 300                *--p = 0;
 301        len = p - s;
 302        if (slash)
 303                len += strlen(slash);
 304        p = xmalloc(len + 1);
 305        strcpy(p, s);
 306        if (slash)
 307                strcat(p, slash);
 308
 309        /*
 310         * With "slash", e.g. "git fetch jgarzik/netdev-2.6" when
 311         * reading from $GIT_DIR/branches/jgarzik fetches "HEAD" from
 312         * the partial URL obtained from the branches file plus
 313         * "/netdev-2.6" and does not store it in any tracking ref.
 314         * #branch specifier in the file is ignored.
 315         *
 316         * Otherwise, the branches file would have URL and optionally
 317         * #branch specified.  The "master" (or specified) branch is
 318         * fetched and stored in the local branch of the same name.
 319         */
 320        frag = strchr(p, '#');
 321        if (frag) {
 322                *(frag++) = '\0';
 323                strbuf_addf(&branch, "refs/heads/%s", frag);
 324        } else
 325                strbuf_addstr(&branch, "refs/heads/master");
 326        if (!slash) {
 327                strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 328        } else {
 329                strbuf_reset(&branch);
 330                strbuf_addstr(&branch, "HEAD:");
 331        }
 332        add_url_alias(remote, p);
 333        add_fetch_refspec(remote, strbuf_detach(&branch, NULL));
 334        /*
 335         * Cogito compatible push: push current HEAD to remote #branch
 336         * (master if missing)
 337         */
 338        strbuf_init(&branch, 0);
 339        strbuf_addstr(&branch, "HEAD");
 340        if (frag)
 341                strbuf_addf(&branch, ":refs/heads/%s", frag);
 342        else
 343                strbuf_addstr(&branch, ":refs/heads/master");
 344        add_push_refspec(remote, strbuf_detach(&branch, NULL));
 345        remote->fetch_tags = 1; /* always auto-follow */
 346}
 347
 348static int handle_config(const char *key, const char *value, void *cb)
 349{
 350        const char *name;
 351        const char *subkey;
 352        struct remote *remote;
 353        struct branch *branch;
 354        if (!prefixcmp(key, "branch.")) {
 355                name = key + 7;
 356                subkey = strrchr(name, '.');
 357                if (!subkey)
 358                        return 0;
 359                branch = make_branch(name, subkey - name);
 360                if (!strcmp(subkey, ".remote")) {
 361                        if (git_config_string(&branch->remote_name, key, value))
 362                                return -1;
 363                        if (branch == current_branch) {
 364                                default_remote_name = branch->remote_name;
 365                                explicit_default_remote_name = 1;
 366                        }
 367                } else if (!strcmp(subkey, ".pushremote")) {
 368                        if (branch == current_branch)
 369                                if (git_config_string(&pushremote_name, key, value))
 370                                        return -1;
 371                } else if (!strcmp(subkey, ".merge")) {
 372                        if (!value)
 373                                return config_error_nonbool(key);
 374                        add_merge(branch, xstrdup(value));
 375                }
 376                return 0;
 377        }
 378        if (!prefixcmp(key, "url.")) {
 379                struct rewrite *rewrite;
 380                name = key + 4;
 381                subkey = strrchr(name, '.');
 382                if (!subkey)
 383                        return 0;
 384                if (!strcmp(subkey, ".insteadof")) {
 385                        rewrite = make_rewrite(&rewrites, name, subkey - name);
 386                        if (!value)
 387                                return config_error_nonbool(key);
 388                        add_instead_of(rewrite, xstrdup(value));
 389                } else if (!strcmp(subkey, ".pushinsteadof")) {
 390                        rewrite = make_rewrite(&rewrites_push, name, subkey - name);
 391                        if (!value)
 392                                return config_error_nonbool(key);
 393                        add_instead_of(rewrite, xstrdup(value));
 394                }
 395        }
 396
 397        if (prefixcmp(key,  "remote."))
 398                return 0;
 399        name = key + 7;
 400
 401        /* Handle remote.* variables */
 402        if (!strcmp(name, "pushdefault"))
 403                return git_config_string(&pushremote_name, key, value);
 404
 405        /* Handle remote.<name>.* variables */
 406        if (*name == '/') {
 407                warning("Config remote shorthand cannot begin with '/': %s",
 408                        name);
 409                return 0;
 410        }
 411        subkey = strrchr(name, '.');
 412        if (!subkey)
 413                return 0;
 414        remote = make_remote(name, subkey - name);
 415        remote->origin = REMOTE_CONFIG;
 416        if (!strcmp(subkey, ".mirror"))
 417                remote->mirror = git_config_bool(key, value);
 418        else if (!strcmp(subkey, ".skipdefaultupdate"))
 419                remote->skip_default_update = git_config_bool(key, value);
 420        else if (!strcmp(subkey, ".skipfetchall"))
 421                remote->skip_default_update = git_config_bool(key, value);
 422        else if (!strcmp(subkey, ".url")) {
 423                const char *v;
 424                if (git_config_string(&v, key, value))
 425                        return -1;
 426                add_url(remote, v);
 427        } else if (!strcmp(subkey, ".pushurl")) {
 428                const char *v;
 429                if (git_config_string(&v, key, value))
 430                        return -1;
 431                add_pushurl(remote, v);
 432        } else if (!strcmp(subkey, ".push")) {
 433                const char *v;
 434                if (git_config_string(&v, key, value))
 435                        return -1;
 436                add_push_refspec(remote, v);
 437        } else if (!strcmp(subkey, ".fetch")) {
 438                const char *v;
 439                if (git_config_string(&v, key, value))
 440                        return -1;
 441                add_fetch_refspec(remote, v);
 442        } else if (!strcmp(subkey, ".receivepack")) {
 443                const char *v;
 444                if (git_config_string(&v, key, value))
 445                        return -1;
 446                if (!remote->receivepack)
 447                        remote->receivepack = v;
 448                else
 449                        error("more than one receivepack given, using the first");
 450        } else if (!strcmp(subkey, ".uploadpack")) {
 451                const char *v;
 452                if (git_config_string(&v, key, value))
 453                        return -1;
 454                if (!remote->uploadpack)
 455                        remote->uploadpack = v;
 456                else
 457                        error("more than one uploadpack given, using the first");
 458        } else if (!strcmp(subkey, ".tagopt")) {
 459                if (!strcmp(value, "--no-tags"))
 460                        remote->fetch_tags = -1;
 461                else if (!strcmp(value, "--tags"))
 462                        remote->fetch_tags = 2;
 463        } else if (!strcmp(subkey, ".proxy")) {
 464                return git_config_string((const char **)&remote->http_proxy,
 465                                         key, value);
 466        } else if (!strcmp(subkey, ".vcs")) {
 467                return git_config_string(&remote->foreign_vcs, key, value);
 468        }
 469        return 0;
 470}
 471
 472static void alias_all_urls(void)
 473{
 474        int i, j;
 475        for (i = 0; i < remotes_nr; i++) {
 476                int add_pushurl_aliases;
 477                if (!remotes[i])
 478                        continue;
 479                for (j = 0; j < remotes[i]->pushurl_nr; j++) {
 480                        remotes[i]->pushurl[j] = alias_url(remotes[i]->pushurl[j], &rewrites);
 481                }
 482                add_pushurl_aliases = remotes[i]->pushurl_nr == 0;
 483                for (j = 0; j < remotes[i]->url_nr; j++) {
 484                        if (add_pushurl_aliases)
 485                                add_pushurl_alias(remotes[i], remotes[i]->url[j]);
 486                        remotes[i]->url[j] = alias_url(remotes[i]->url[j], &rewrites);
 487                }
 488        }
 489}
 490
 491static void read_config(void)
 492{
 493        unsigned char sha1[20];
 494        const char *head_ref;
 495        int flag;
 496        if (default_remote_name) /* did this already */
 497                return;
 498        default_remote_name = xstrdup("origin");
 499        current_branch = NULL;
 500        head_ref = resolve_ref_unsafe("HEAD", sha1, 0, &flag);
 501        if (head_ref && (flag & REF_ISSYMREF) &&
 502            !prefixcmp(head_ref, "refs/heads/")) {
 503                current_branch =
 504                        make_branch(head_ref + strlen("refs/heads/"), 0);
 505        }
 506        git_config(handle_config, NULL);
 507        alias_all_urls();
 508}
 509
 510/*
 511 * This function frees a refspec array.
 512 * Warning: code paths should be checked to ensure that the src
 513 *          and dst pointers are always freeable pointers as well
 514 *          as the refspec pointer itself.
 515 */
 516static void free_refspecs(struct refspec *refspec, int nr_refspec)
 517{
 518        int i;
 519
 520        if (!refspec)
 521                return;
 522
 523        for (i = 0; i < nr_refspec; i++) {
 524                free(refspec[i].src);
 525                free(refspec[i].dst);
 526        }
 527        free(refspec);
 528}
 529
 530static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 531{
 532        int i;
 533        struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 534
 535        for (i = 0; i < nr_refspec; i++) {
 536                size_t llen;
 537                int is_glob;
 538                const char *lhs, *rhs;
 539                int flags;
 540
 541                is_glob = 0;
 542
 543                lhs = refspec[i];
 544                if (*lhs == '+') {
 545                        rs[i].force = 1;
 546                        lhs++;
 547                }
 548
 549                rhs = strrchr(lhs, ':');
 550
 551                /*
 552                 * Before going on, special case ":" (or "+:") as a refspec
 553                 * for pushing matching refs.
 554                 */
 555                if (!fetch && rhs == lhs && rhs[1] == '\0') {
 556                        rs[i].matching = 1;
 557                        continue;
 558                }
 559
 560                if (rhs) {
 561                        size_t rlen = strlen(++rhs);
 562                        is_glob = (1 <= rlen && strchr(rhs, '*'));
 563                        rs[i].dst = xstrndup(rhs, rlen);
 564                }
 565
 566                llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 567                if (1 <= llen && memchr(lhs, '*', llen)) {
 568                        if ((rhs && !is_glob) || (!rhs && fetch))
 569                                goto invalid;
 570                        is_glob = 1;
 571                } else if (rhs && is_glob) {
 572                        goto invalid;
 573                }
 574
 575                rs[i].pattern = is_glob;
 576                rs[i].src = xstrndup(lhs, llen);
 577                flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 578
 579                if (fetch) {
 580                        unsigned char unused[40];
 581
 582                        /* LHS */
 583                        if (!*rs[i].src)
 584                                ; /* empty is ok; it means "HEAD" */
 585                        else if (llen == 40 && !get_sha1_hex(rs[i].src, unused))
 586                                rs[i].exact_sha1 = 1; /* ok */
 587                        else if (!check_refname_format(rs[i].src, flags))
 588                                ; /* valid looking ref is ok */
 589                        else
 590                                goto invalid;
 591                        /* RHS */
 592                        if (!rs[i].dst)
 593                                ; /* missing is ok; it is the same as empty */
 594                        else if (!*rs[i].dst)
 595                                ; /* empty is ok; it means "do not store" */
 596                        else if (!check_refname_format(rs[i].dst, flags))
 597                                ; /* valid looking ref is ok */
 598                        else
 599                                goto invalid;
 600                } else {
 601                        /*
 602                         * LHS
 603                         * - empty is allowed; it means delete.
 604                         * - when wildcarded, it must be a valid looking ref.
 605                         * - otherwise, it must be an extended SHA-1, but
 606                         *   there is no existing way to validate this.
 607                         */
 608                        if (!*rs[i].src)
 609                                ; /* empty is ok */
 610                        else if (is_glob) {
 611                                if (check_refname_format(rs[i].src, flags))
 612                                        goto invalid;
 613                        }
 614                        else
 615                                ; /* anything goes, for now */
 616                        /*
 617                         * RHS
 618                         * - missing is allowed, but LHS then must be a
 619                         *   valid looking ref.
 620                         * - empty is not allowed.
 621                         * - otherwise it must be a valid looking ref.
 622                         */
 623                        if (!rs[i].dst) {
 624                                if (check_refname_format(rs[i].src, flags))
 625                                        goto invalid;
 626                        } else if (!*rs[i].dst) {
 627                                goto invalid;
 628                        } else {
 629                                if (check_refname_format(rs[i].dst, flags))
 630                                        goto invalid;
 631                        }
 632                }
 633        }
 634        return rs;
 635
 636 invalid:
 637        if (verify) {
 638                /*
 639                 * nr_refspec must be greater than zero and i must be valid
 640                 * since it is only possible to reach this point from within
 641                 * the for loop above.
 642                 */
 643                free_refspecs(rs, i+1);
 644                return NULL;
 645        }
 646        die("Invalid refspec '%s'", refspec[i]);
 647}
 648
 649int valid_fetch_refspec(const char *fetch_refspec_str)
 650{
 651        struct refspec *refspec;
 652
 653        refspec = parse_refspec_internal(1, &fetch_refspec_str, 1, 1);
 654        free_refspecs(refspec, 1);
 655        return !!refspec;
 656}
 657
 658struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 659{
 660        return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 661}
 662
 663static struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 664{
 665        return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 666}
 667
 668void free_refspec(int nr_refspec, struct refspec *refspec)
 669{
 670        int i;
 671        for (i = 0; i < nr_refspec; i++) {
 672                free(refspec[i].src);
 673                free(refspec[i].dst);
 674        }
 675        free(refspec);
 676}
 677
 678static int valid_remote_nick(const char *name)
 679{
 680        if (!name[0] || is_dot_or_dotdot(name))
 681                return 0;
 682        return !strchr(name, '/'); /* no slash */
 683}
 684
 685static struct remote *remote_get_1(const char *name, const char *pushremote_name)
 686{
 687        struct remote *ret;
 688        int name_given = 0;
 689
 690        if (name)
 691                name_given = 1;
 692        else {
 693                if (pushremote_name) {
 694                        name = pushremote_name;
 695                        name_given = 1;
 696                } else {
 697                        name = default_remote_name;
 698                        name_given = explicit_default_remote_name;
 699                }
 700        }
 701
 702        ret = make_remote(name, 0);
 703        if (valid_remote_nick(name)) {
 704                if (!valid_remote(ret))
 705                        read_remotes_file(ret);
 706                if (!valid_remote(ret))
 707                        read_branches_file(ret);
 708        }
 709        if (name_given && !valid_remote(ret))
 710                add_url_alias(ret, name);
 711        if (!valid_remote(ret))
 712                return NULL;
 713        ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 714        ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 715        return ret;
 716}
 717
 718struct remote *remote_get(const char *name)
 719{
 720        read_config();
 721        return remote_get_1(name, NULL);
 722}
 723
 724struct remote *pushremote_get(const char *name)
 725{
 726        read_config();
 727        return remote_get_1(name, pushremote_name);
 728}
 729
 730int remote_is_configured(const char *name)
 731{
 732        int i;
 733        read_config();
 734
 735        for (i = 0; i < remotes_nr; i++)
 736                if (!strcmp(name, remotes[i]->name))
 737                        return 1;
 738        return 0;
 739}
 740
 741int for_each_remote(each_remote_fn fn, void *priv)
 742{
 743        int i, result = 0;
 744        read_config();
 745        for (i = 0; i < remotes_nr && !result; i++) {
 746                struct remote *r = remotes[i];
 747                if (!r)
 748                        continue;
 749                if (!r->fetch)
 750                        r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 751                                                       r->fetch_refspec);
 752                if (!r->push)
 753                        r->push = parse_push_refspec(r->push_refspec_nr,
 754                                                     r->push_refspec);
 755                result = fn(r, priv);
 756        }
 757        return result;
 758}
 759
 760void ref_remove_duplicates(struct ref *ref_map)
 761{
 762        struct string_list refs = STRING_LIST_INIT_NODUP;
 763        struct string_list_item *item = NULL;
 764        struct ref *prev = NULL, *next = NULL;
 765        for (; ref_map; prev = ref_map, ref_map = next) {
 766                next = ref_map->next;
 767                if (!ref_map->peer_ref)
 768                        continue;
 769
 770                item = string_list_lookup(&refs, ref_map->peer_ref->name);
 771                if (item) {
 772                        if (strcmp(((struct ref *)item->util)->name,
 773                                   ref_map->name))
 774                                die("%s tracks both %s and %s",
 775                                    ref_map->peer_ref->name,
 776                                    ((struct ref *)item->util)->name,
 777                                    ref_map->name);
 778                        prev->next = ref_map->next;
 779                        free(ref_map->peer_ref);
 780                        free(ref_map);
 781                        ref_map = prev; /* skip this; we freed it */
 782                        continue;
 783                }
 784
 785                item = string_list_insert(&refs, ref_map->peer_ref->name);
 786                item->util = ref_map;
 787        }
 788        string_list_clear(&refs, 0);
 789}
 790
 791int remote_has_url(struct remote *remote, const char *url)
 792{
 793        int i;
 794        for (i = 0; i < remote->url_nr; i++) {
 795                if (!strcmp(remote->url[i], url))
 796                        return 1;
 797        }
 798        return 0;
 799}
 800
 801static int match_name_with_pattern(const char *key, const char *name,
 802                                   const char *value, char **result)
 803{
 804        const char *kstar = strchr(key, '*');
 805        size_t klen;
 806        size_t ksuffixlen;
 807        size_t namelen;
 808        int ret;
 809        if (!kstar)
 810                die("Key '%s' of pattern had no '*'", key);
 811        klen = kstar - key;
 812        ksuffixlen = strlen(kstar + 1);
 813        namelen = strlen(name);
 814        ret = !strncmp(name, key, klen) && namelen >= klen + ksuffixlen &&
 815                !memcmp(name + namelen - ksuffixlen, kstar + 1, ksuffixlen);
 816        if (ret && value) {
 817                const char *vstar = strchr(value, '*');
 818                size_t vlen;
 819                size_t vsuffixlen;
 820                if (!vstar)
 821                        die("Value '%s' of pattern has no '*'", value);
 822                vlen = vstar - value;
 823                vsuffixlen = strlen(vstar + 1);
 824                *result = xmalloc(vlen + vsuffixlen +
 825                                  strlen(name) -
 826                                  klen - ksuffixlen + 1);
 827                strncpy(*result, value, vlen);
 828                strncpy(*result + vlen,
 829                        name + klen, namelen - klen - ksuffixlen);
 830                strcpy(*result + vlen + namelen - klen - ksuffixlen,
 831                       vstar + 1);
 832        }
 833        return ret;
 834}
 835
 836static int query_refspecs(struct refspec *refs, int ref_count, struct refspec *query)
 837{
 838        int i;
 839        int find_src = !query->src;
 840
 841        if (find_src && !query->dst)
 842                return error("query_refspecs: need either src or dst");
 843
 844        for (i = 0; i < ref_count; i++) {
 845                struct refspec *refspec = &refs[i];
 846                const char *key = find_src ? refspec->dst : refspec->src;
 847                const char *value = find_src ? refspec->src : refspec->dst;
 848                const char *needle = find_src ? query->dst : query->src;
 849                char **result = find_src ? &query->src : &query->dst;
 850
 851                if (!refspec->dst)
 852                        continue;
 853                if (refspec->pattern) {
 854                        if (match_name_with_pattern(key, needle, value, result)) {
 855                                query->force = refspec->force;
 856                                return 0;
 857                        }
 858                } else if (!strcmp(needle, key)) {
 859                        *result = xstrdup(value);
 860                        query->force = refspec->force;
 861                        return 0;
 862                }
 863        }
 864        return -1;
 865}
 866
 867char *apply_refspecs(struct refspec *refspecs, int nr_refspec,
 868                     const char *name)
 869{
 870        struct refspec query;
 871
 872        memset(&query, 0, sizeof(struct refspec));
 873        query.src = (char *)name;
 874
 875        if (query_refspecs(refspecs, nr_refspec, &query))
 876                return NULL;
 877
 878        return query.dst;
 879}
 880
 881int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 882{
 883        return query_refspecs(remote->fetch, remote->fetch_refspec_nr, refspec);
 884}
 885
 886static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 887                const char *name)
 888{
 889        size_t len = strlen(name);
 890        struct ref *ref = xcalloc(1, sizeof(struct ref) + prefixlen + len + 1);
 891        memcpy(ref->name, prefix, prefixlen);
 892        memcpy(ref->name + prefixlen, name, len);
 893        return ref;
 894}
 895
 896struct ref *alloc_ref(const char *name)
 897{
 898        return alloc_ref_with_prefix("", 0, name);
 899}
 900
 901struct ref *copy_ref(const struct ref *ref)
 902{
 903        struct ref *cpy;
 904        size_t len;
 905        if (!ref)
 906                return NULL;
 907        len = strlen(ref->name);
 908        cpy = xmalloc(sizeof(struct ref) + len + 1);
 909        memcpy(cpy, ref, sizeof(struct ref) + len + 1);
 910        cpy->next = NULL;
 911        cpy->symref = ref->symref ? xstrdup(ref->symref) : NULL;
 912        cpy->remote_status = ref->remote_status ? xstrdup(ref->remote_status) : NULL;
 913        cpy->peer_ref = copy_ref(ref->peer_ref);
 914        return cpy;
 915}
 916
 917struct ref *copy_ref_list(const struct ref *ref)
 918{
 919        struct ref *ret = NULL;
 920        struct ref **tail = &ret;
 921        while (ref) {
 922                *tail = copy_ref(ref);
 923                ref = ref->next;
 924                tail = &((*tail)->next);
 925        }
 926        return ret;
 927}
 928
 929static void free_ref(struct ref *ref)
 930{
 931        if (!ref)
 932                return;
 933        free_ref(ref->peer_ref);
 934        free(ref->remote_status);
 935        free(ref->symref);
 936        free(ref);
 937}
 938
 939void free_refs(struct ref *ref)
 940{
 941        struct ref *next;
 942        while (ref) {
 943                next = ref->next;
 944                free_ref(ref);
 945                ref = next;
 946        }
 947}
 948
 949int ref_compare_name(const void *va, const void *vb)
 950{
 951        const struct ref *a = va, *b = vb;
 952        return strcmp(a->name, b->name);
 953}
 954
 955static void *ref_list_get_next(const void *a)
 956{
 957        return ((const struct ref *)a)->next;
 958}
 959
 960static void ref_list_set_next(void *a, void *next)
 961{
 962        ((struct ref *)a)->next = next;
 963}
 964
 965void sort_ref_list(struct ref **l, int (*cmp)(const void *, const void *))
 966{
 967        *l = llist_mergesort(*l, ref_list_get_next, ref_list_set_next, cmp);
 968}
 969
 970static int count_refspec_match(const char *pattern,
 971                               struct ref *refs,
 972                               struct ref **matched_ref)
 973{
 974        int patlen = strlen(pattern);
 975        struct ref *matched_weak = NULL;
 976        struct ref *matched = NULL;
 977        int weak_match = 0;
 978        int match = 0;
 979
 980        for (weak_match = match = 0; refs; refs = refs->next) {
 981                char *name = refs->name;
 982                int namelen = strlen(name);
 983
 984                if (!refname_match(pattern, name, ref_rev_parse_rules))
 985                        continue;
 986
 987                /* A match is "weak" if it is with refs outside
 988                 * heads or tags, and did not specify the pattern
 989                 * in full (e.g. "refs/remotes/origin/master") or at
 990                 * least from the toplevel (e.g. "remotes/origin/master");
 991                 * otherwise "git push $URL master" would result in
 992                 * ambiguity between remotes/origin/master and heads/master
 993                 * at the remote site.
 994                 */
 995                if (namelen != patlen &&
 996                    patlen != namelen - 5 &&
 997                    prefixcmp(name, "refs/heads/") &&
 998                    prefixcmp(name, "refs/tags/")) {
 999                        /* We want to catch the case where only weak
1000                         * matches are found and there are multiple
1001                         * matches, and where more than one strong
1002                         * matches are found, as ambiguous.  One
1003                         * strong match with zero or more weak matches
1004                         * are acceptable as a unique match.
1005                         */
1006                        matched_weak = refs;
1007                        weak_match++;
1008                }
1009                else {
1010                        matched = refs;
1011                        match++;
1012                }
1013        }
1014        if (!matched) {
1015                *matched_ref = matched_weak;
1016                return weak_match;
1017        }
1018        else {
1019                *matched_ref = matched;
1020                return match;
1021        }
1022}
1023
1024static void tail_link_ref(struct ref *ref, struct ref ***tail)
1025{
1026        **tail = ref;
1027        while (ref->next)
1028                ref = ref->next;
1029        *tail = &ref->next;
1030}
1031
1032static struct ref *alloc_delete_ref(void)
1033{
1034        struct ref *ref = alloc_ref("(delete)");
1035        hashclr(ref->new_sha1);
1036        return ref;
1037}
1038
1039static struct ref *try_explicit_object_name(const char *name)
1040{
1041        unsigned char sha1[20];
1042        struct ref *ref;
1043
1044        if (!*name)
1045                return alloc_delete_ref();
1046        if (get_sha1(name, sha1))
1047                return NULL;
1048        ref = alloc_ref(name);
1049        hashcpy(ref->new_sha1, sha1);
1050        return ref;
1051}
1052
1053static struct ref *make_linked_ref(const char *name, struct ref ***tail)
1054{
1055        struct ref *ret = alloc_ref(name);
1056        tail_link_ref(ret, tail);
1057        return ret;
1058}
1059
1060static char *guess_ref(const char *name, struct ref *peer)
1061{
1062        struct strbuf buf = STRBUF_INIT;
1063        unsigned char sha1[20];
1064
1065        const char *r = resolve_ref_unsafe(peer->name, sha1, 1, NULL);
1066        if (!r)
1067                return NULL;
1068
1069        if (!prefixcmp(r, "refs/heads/"))
1070                strbuf_addstr(&buf, "refs/heads/");
1071        else if (!prefixcmp(r, "refs/tags/"))
1072                strbuf_addstr(&buf, "refs/tags/");
1073        else
1074                return NULL;
1075
1076        strbuf_addstr(&buf, name);
1077        return strbuf_detach(&buf, NULL);
1078}
1079
1080static int match_explicit(struct ref *src, struct ref *dst,
1081                          struct ref ***dst_tail,
1082                          struct refspec *rs)
1083{
1084        struct ref *matched_src, *matched_dst;
1085        int copy_src;
1086
1087        const char *dst_value = rs->dst;
1088        char *dst_guess;
1089
1090        if (rs->pattern || rs->matching)
1091                return 0;
1092
1093        matched_src = matched_dst = NULL;
1094        switch (count_refspec_match(rs->src, src, &matched_src)) {
1095        case 1:
1096                copy_src = 1;
1097                break;
1098        case 0:
1099                /* The source could be in the get_sha1() format
1100                 * not a reference name.  :refs/other is a
1101                 * way to delete 'other' ref at the remote end.
1102                 */
1103                matched_src = try_explicit_object_name(rs->src);
1104                if (!matched_src)
1105                        return error("src refspec %s does not match any.", rs->src);
1106                copy_src = 0;
1107                break;
1108        default:
1109                return error("src refspec %s matches more than one.", rs->src);
1110        }
1111
1112        if (!dst_value) {
1113                unsigned char sha1[20];
1114                int flag;
1115
1116                dst_value = resolve_ref_unsafe(matched_src->name, sha1, 1, &flag);
1117                if (!dst_value ||
1118                    ((flag & REF_ISSYMREF) &&
1119                     prefixcmp(dst_value, "refs/heads/")))
1120                        die("%s cannot be resolved to branch.",
1121                            matched_src->name);
1122        }
1123
1124        switch (count_refspec_match(dst_value, dst, &matched_dst)) {
1125        case 1:
1126                break;
1127        case 0:
1128                if (!memcmp(dst_value, "refs/", 5))
1129                        matched_dst = make_linked_ref(dst_value, dst_tail);
1130                else if (is_null_sha1(matched_src->new_sha1))
1131                        error("unable to delete '%s': remote ref does not exist",
1132                              dst_value);
1133                else if ((dst_guess = guess_ref(dst_value, matched_src)))
1134                        matched_dst = make_linked_ref(dst_guess, dst_tail);
1135                else
1136                        error("unable to push to unqualified destination: %s\n"
1137                              "The destination refspec neither matches an "
1138                              "existing ref on the remote nor\n"
1139                              "begins with refs/, and we are unable to "
1140                              "guess a prefix based on the source ref.",
1141                              dst_value);
1142                break;
1143        default:
1144                matched_dst = NULL;
1145                error("dst refspec %s matches more than one.",
1146                      dst_value);
1147                break;
1148        }
1149        if (!matched_dst)
1150                return -1;
1151        if (matched_dst->peer_ref)
1152                return error("dst ref %s receives from more than one src.",
1153                      matched_dst->name);
1154        else {
1155                matched_dst->peer_ref = copy_src ? copy_ref(matched_src) : matched_src;
1156                matched_dst->force = rs->force;
1157        }
1158        return 0;
1159}
1160
1161static int match_explicit_refs(struct ref *src, struct ref *dst,
1162                               struct ref ***dst_tail, struct refspec *rs,
1163                               int rs_nr)
1164{
1165        int i, errs;
1166        for (i = errs = 0; i < rs_nr; i++)
1167                errs += match_explicit(src, dst, dst_tail, &rs[i]);
1168        return errs;
1169}
1170
1171static char *get_ref_match(const struct refspec *rs, int rs_nr, const struct ref *ref,
1172                int send_mirror, int direction, const struct refspec **ret_pat)
1173{
1174        const struct refspec *pat;
1175        char *name;
1176        int i;
1177        int matching_refs = -1;
1178        for (i = 0; i < rs_nr; i++) {
1179                if (rs[i].matching &&
1180                    (matching_refs == -1 || rs[i].force)) {
1181                        matching_refs = i;
1182                        continue;
1183                }
1184
1185                if (rs[i].pattern) {
1186                        const char *dst_side = rs[i].dst ? rs[i].dst : rs[i].src;
1187                        int match;
1188                        if (direction == FROM_SRC)
1189                                match = match_name_with_pattern(rs[i].src, ref->name, dst_side, &name);
1190                        else
1191                                match = match_name_with_pattern(dst_side, ref->name, rs[i].src, &name);
1192                        if (match) {
1193                                matching_refs = i;
1194                                break;
1195                        }
1196                }
1197        }
1198        if (matching_refs == -1)
1199                return NULL;
1200
1201        pat = rs + matching_refs;
1202        if (pat->matching) {
1203                /*
1204                 * "matching refs"; traditionally we pushed everything
1205                 * including refs outside refs/heads/ hierarchy, but
1206                 * that does not make much sense these days.
1207                 */
1208                if (!send_mirror && prefixcmp(ref->name, "refs/heads/"))
1209                        return NULL;
1210                name = xstrdup(ref->name);
1211        }
1212        if (ret_pat)
1213                *ret_pat = pat;
1214        return name;
1215}
1216
1217static struct ref **tail_ref(struct ref **head)
1218{
1219        struct ref **tail = head;
1220        while (*tail)
1221                tail = &((*tail)->next);
1222        return tail;
1223}
1224
1225struct tips {
1226        struct commit **tip;
1227        int nr, alloc;
1228};
1229
1230static void add_to_tips(struct tips *tips, const unsigned char *sha1)
1231{
1232        struct commit *commit;
1233
1234        if (is_null_sha1(sha1))
1235                return;
1236        commit = lookup_commit_reference_gently(sha1, 1);
1237        if (!commit || (commit->object.flags & TMP_MARK))
1238                return;
1239        commit->object.flags |= TMP_MARK;
1240        ALLOC_GROW(tips->tip, tips->nr + 1, tips->alloc);
1241        tips->tip[tips->nr++] = commit;
1242}
1243
1244static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***dst_tail)
1245{
1246        struct string_list dst_tag = STRING_LIST_INIT_NODUP;
1247        struct string_list src_tag = STRING_LIST_INIT_NODUP;
1248        struct string_list_item *item;
1249        struct ref *ref;
1250        struct tips sent_tips;
1251
1252        /*
1253         * Collect everything we know they would have at the end of
1254         * this push, and collect all tags they have.
1255         */
1256        memset(&sent_tips, 0, sizeof(sent_tips));
1257        for (ref = *dst; ref; ref = ref->next) {
1258                if (ref->peer_ref &&
1259                    !is_null_sha1(ref->peer_ref->new_sha1))
1260                        add_to_tips(&sent_tips, ref->peer_ref->new_sha1);
1261                else
1262                        add_to_tips(&sent_tips, ref->old_sha1);
1263                if (!prefixcmp(ref->name, "refs/tags/"))
1264                        string_list_append(&dst_tag, ref->name);
1265        }
1266        clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
1267
1268        sort_string_list(&dst_tag);
1269
1270        /* Collect tags they do not have. */
1271        for (ref = src; ref; ref = ref->next) {
1272                if (prefixcmp(ref->name, "refs/tags/"))
1273                        continue; /* not a tag */
1274                if (string_list_has_string(&dst_tag, ref->name))
1275                        continue; /* they already have it */
1276                if (sha1_object_info(ref->new_sha1, NULL) != OBJ_TAG)
1277                        continue; /* be conservative */
1278                item = string_list_append(&src_tag, ref->name);
1279                item->util = ref;
1280        }
1281        string_list_clear(&dst_tag, 0);
1282
1283        /*
1284         * At this point, src_tag lists tags that are missing from
1285         * dst, and sent_tips lists the tips we are pushing or those
1286         * that we know they already have. An element in the src_tag
1287         * that is an ancestor of any of the sent_tips needs to be
1288         * sent to the other side.
1289         */
1290        if (sent_tips.nr) {
1291                for_each_string_list_item(item, &src_tag) {
1292                        struct ref *ref = item->util;
1293                        struct ref *dst_ref;
1294                        struct commit *commit;
1295
1296                        if (is_null_sha1(ref->new_sha1))
1297                                continue;
1298                        commit = lookup_commit_reference_gently(ref->new_sha1, 1);
1299                        if (!commit)
1300                                /* not pushing a commit, which is not an error */
1301                                continue;
1302
1303                        /*
1304                         * Is this tag, which they do not have, reachable from
1305                         * any of the commits we are sending?
1306                         */
1307                        if (!in_merge_bases_many(commit, sent_tips.nr, sent_tips.tip))
1308                                continue;
1309
1310                        /* Add it in */
1311                        dst_ref = make_linked_ref(ref->name, dst_tail);
1312                        hashcpy(dst_ref->new_sha1, ref->new_sha1);
1313                        dst_ref->peer_ref = copy_ref(ref);
1314                }
1315        }
1316        string_list_clear(&src_tag, 0);
1317        free(sent_tips.tip);
1318}
1319
1320/*
1321 * Given the set of refs the local repository has, the set of refs the
1322 * remote repository has, and the refspec used for push, determine
1323 * what remote refs we will update and with what value by setting
1324 * peer_ref (which object is being pushed) and force (if the push is
1325 * forced) in elements of "dst". The function may add new elements to
1326 * dst (e.g. pushing to a new branch, done in match_explicit_refs).
1327 */
1328int match_push_refs(struct ref *src, struct ref **dst,
1329                    int nr_refspec, const char **refspec, int flags)
1330{
1331        struct refspec *rs;
1332        int send_all = flags & MATCH_REFS_ALL;
1333        int send_mirror = flags & MATCH_REFS_MIRROR;
1334        int send_prune = flags & MATCH_REFS_PRUNE;
1335        int errs;
1336        static const char *default_refspec[] = { ":", NULL };
1337        struct ref *ref, **dst_tail = tail_ref(dst);
1338
1339        if (!nr_refspec) {
1340                nr_refspec = 1;
1341                refspec = default_refspec;
1342        }
1343        rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1344        errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
1345
1346        /* pick the remainder */
1347        for (ref = src; ref; ref = ref->next) {
1348                struct ref *dst_peer;
1349                const struct refspec *pat = NULL;
1350                char *dst_name;
1351
1352                dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
1353                if (!dst_name)
1354                        continue;
1355
1356                dst_peer = find_ref_by_name(*dst, dst_name);
1357                if (dst_peer) {
1358                        if (dst_peer->peer_ref)
1359                                /* We're already sending something to this ref. */
1360                                goto free_name;
1361                } else {
1362                        if (pat->matching && !(send_all || send_mirror))
1363                                /*
1364                                 * Remote doesn't have it, and we have no
1365                                 * explicit pattern, and we don't have
1366                                 * --all nor --mirror.
1367                                 */
1368                                goto free_name;
1369
1370                        /* Create a new one and link it */
1371                        dst_peer = make_linked_ref(dst_name, &dst_tail);
1372                        hashcpy(dst_peer->new_sha1, ref->new_sha1);
1373                }
1374                dst_peer->peer_ref = copy_ref(ref);
1375                dst_peer->force = pat->force;
1376        free_name:
1377                free(dst_name);
1378        }
1379
1380        if (flags & MATCH_REFS_FOLLOW_TAGS)
1381                add_missing_tags(src, dst, &dst_tail);
1382
1383        if (send_prune) {
1384                /* check for missing refs on the remote */
1385                for (ref = *dst; ref; ref = ref->next) {
1386                        char *src_name;
1387
1388                        if (ref->peer_ref)
1389                                /* We're already sending something to this ref. */
1390                                continue;
1391
1392                        src_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_DST, NULL);
1393                        if (src_name) {
1394                                if (!find_ref_by_name(src, src_name))
1395                                        ref->peer_ref = alloc_delete_ref();
1396                                free(src_name);
1397                        }
1398                }
1399        }
1400        if (errs)
1401                return -1;
1402        return 0;
1403}
1404
1405void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
1406        int force_update)
1407{
1408        struct ref *ref;
1409
1410        for (ref = remote_refs; ref; ref = ref->next) {
1411                int force_ref_update = ref->force || force_update;
1412
1413                if (ref->peer_ref)
1414                        hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
1415                else if (!send_mirror)
1416                        continue;
1417
1418                ref->deletion = is_null_sha1(ref->new_sha1);
1419                if (!ref->deletion &&
1420                        !hashcmp(ref->old_sha1, ref->new_sha1)) {
1421                        ref->status = REF_STATUS_UPTODATE;
1422                        continue;
1423                }
1424
1425                /*
1426                 * Decide whether an individual refspec A:B can be
1427                 * pushed.  The push will succeed if any of the
1428                 * following are true:
1429                 *
1430                 * (1) the remote reference B does not exist
1431                 *
1432                 * (2) the remote reference B is being removed (i.e.,
1433                 *     pushing :B where no source is specified)
1434                 *
1435                 * (3) the destination is not under refs/tags/, and
1436                 *     if the old and new value is a commit, the new
1437                 *     is a descendant of the old.
1438                 *
1439                 * (4) it is forced using the +A:B notation, or by
1440                 *     passing the --force argument
1441                 */
1442
1443                if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
1444                        int why = 0; /* why would this push require --force? */
1445
1446                        if (!prefixcmp(ref->name, "refs/tags/"))
1447                                why = REF_STATUS_REJECT_ALREADY_EXISTS;
1448                        else if (!has_sha1_file(ref->old_sha1))
1449                                why = REF_STATUS_REJECT_FETCH_FIRST;
1450                        else if (!lookup_commit_reference_gently(ref->old_sha1, 1) ||
1451                                 !lookup_commit_reference_gently(ref->new_sha1, 1))
1452                                why = REF_STATUS_REJECT_NEEDS_FORCE;
1453                        else if (!ref_newer(ref->new_sha1, ref->old_sha1))
1454                                why = REF_STATUS_REJECT_NONFASTFORWARD;
1455
1456                        if (!force_ref_update)
1457                                ref->status = why;
1458                        else if (why)
1459                                ref->forced_update = 1;
1460                }
1461        }
1462}
1463
1464struct branch *branch_get(const char *name)
1465{
1466        struct branch *ret;
1467
1468        read_config();
1469        if (!name || !*name || !strcmp(name, "HEAD"))
1470                ret = current_branch;
1471        else
1472                ret = make_branch(name, 0);
1473        if (ret && ret->remote_name) {
1474                ret->remote = remote_get(ret->remote_name);
1475                if (ret->merge_nr) {
1476                        int i;
1477                        ret->merge = xcalloc(sizeof(*ret->merge),
1478                                             ret->merge_nr);
1479                        for (i = 0; i < ret->merge_nr; i++) {
1480                                ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1481                                ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1482                                if (remote_find_tracking(ret->remote, ret->merge[i])
1483                                    && !strcmp(ret->remote_name, "."))
1484                                        ret->merge[i]->dst = xstrdup(ret->merge_name[i]);
1485                        }
1486                }
1487        }
1488        return ret;
1489}
1490
1491int branch_has_merge_config(struct branch *branch)
1492{
1493        return branch && !!branch->merge;
1494}
1495
1496int branch_merge_matches(struct branch *branch,
1497                                 int i,
1498                                 const char *refname)
1499{
1500        if (!branch || i < 0 || i >= branch->merge_nr)
1501                return 0;
1502        return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
1503}
1504
1505static int ignore_symref_update(const char *refname)
1506{
1507        unsigned char sha1[20];
1508        int flag;
1509
1510        if (!resolve_ref_unsafe(refname, sha1, 0, &flag))
1511                return 0; /* non-existing refs are OK */
1512        return (flag & REF_ISSYMREF);
1513}
1514
1515static struct ref *get_expanded_map(const struct ref *remote_refs,
1516                                    const struct refspec *refspec)
1517{
1518        const struct ref *ref;
1519        struct ref *ret = NULL;
1520        struct ref **tail = &ret;
1521
1522        char *expn_name;
1523
1524        for (ref = remote_refs; ref; ref = ref->next) {
1525                if (strchr(ref->name, '^'))
1526                        continue; /* a dereference item */
1527                if (match_name_with_pattern(refspec->src, ref->name,
1528                                            refspec->dst, &expn_name) &&
1529                    !ignore_symref_update(expn_name)) {
1530                        struct ref *cpy = copy_ref(ref);
1531
1532                        cpy->peer_ref = alloc_ref(expn_name);
1533                        free(expn_name);
1534                        if (refspec->force)
1535                                cpy->peer_ref->force = 1;
1536                        *tail = cpy;
1537                        tail = &cpy->next;
1538                }
1539        }
1540
1541        return ret;
1542}
1543
1544static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1545{
1546        const struct ref *ref;
1547        for (ref = refs; ref; ref = ref->next) {
1548                if (refname_match(name, ref->name, ref_fetch_rules))
1549                        return ref;
1550        }
1551        return NULL;
1552}
1553
1554struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1555{
1556        const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1557
1558        if (!ref)
1559                return NULL;
1560
1561        return copy_ref(ref);
1562}
1563
1564static struct ref *get_local_ref(const char *name)
1565{
1566        if (!name || name[0] == '\0')
1567                return NULL;
1568
1569        if (!prefixcmp(name, "refs/"))
1570                return alloc_ref(name);
1571
1572        if (!prefixcmp(name, "heads/") ||
1573            !prefixcmp(name, "tags/") ||
1574            !prefixcmp(name, "remotes/"))
1575                return alloc_ref_with_prefix("refs/", 5, name);
1576
1577        return alloc_ref_with_prefix("refs/heads/", 11, name);
1578}
1579
1580int get_fetch_map(const struct ref *remote_refs,
1581                  const struct refspec *refspec,
1582                  struct ref ***tail,
1583                  int missing_ok)
1584{
1585        struct ref *ref_map, **rmp;
1586
1587        if (refspec->pattern) {
1588                ref_map = get_expanded_map(remote_refs, refspec);
1589        } else {
1590                const char *name = refspec->src[0] ? refspec->src : "HEAD";
1591
1592                if (refspec->exact_sha1) {
1593                        ref_map = alloc_ref(name);
1594                        get_sha1_hex(name, ref_map->old_sha1);
1595                } else {
1596                        ref_map = get_remote_ref(remote_refs, name);
1597                }
1598                if (!missing_ok && !ref_map)
1599                        die("Couldn't find remote ref %s", name);
1600                if (ref_map) {
1601                        ref_map->peer_ref = get_local_ref(refspec->dst);
1602                        if (ref_map->peer_ref && refspec->force)
1603                                ref_map->peer_ref->force = 1;
1604                }
1605        }
1606
1607        for (rmp = &ref_map; *rmp; ) {
1608                if ((*rmp)->peer_ref) {
1609                        if (prefixcmp((*rmp)->peer_ref->name, "refs/") ||
1610                            check_refname_format((*rmp)->peer_ref->name, 0)) {
1611                                struct ref *ignore = *rmp;
1612                                error("* Ignoring funny ref '%s' locally",
1613                                      (*rmp)->peer_ref->name);
1614                                *rmp = (*rmp)->next;
1615                                free(ignore->peer_ref);
1616                                free(ignore);
1617                                continue;
1618                        }
1619                }
1620                rmp = &((*rmp)->next);
1621        }
1622
1623        if (ref_map)
1624                tail_link_ref(ref_map, tail);
1625
1626        return 0;
1627}
1628
1629int resolve_remote_symref(struct ref *ref, struct ref *list)
1630{
1631        if (!ref->symref)
1632                return 0;
1633        for (; list; list = list->next)
1634                if (!strcmp(ref->symref, list->name)) {
1635                        hashcpy(ref->old_sha1, list->old_sha1);
1636                        return 0;
1637                }
1638        return 1;
1639}
1640
1641static void unmark_and_free(struct commit_list *list, unsigned int mark)
1642{
1643        while (list) {
1644                struct commit_list *temp = list;
1645                temp->item->object.flags &= ~mark;
1646                list = temp->next;
1647                free(temp);
1648        }
1649}
1650
1651int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
1652{
1653        struct object *o;
1654        struct commit *old, *new;
1655        struct commit_list *list, *used;
1656        int found = 0;
1657
1658        /*
1659         * Both new and old must be commit-ish and new is descendant of
1660         * old.  Otherwise we require --force.
1661         */
1662        o = deref_tag(parse_object(old_sha1), NULL, 0);
1663        if (!o || o->type != OBJ_COMMIT)
1664                return 0;
1665        old = (struct commit *) o;
1666
1667        o = deref_tag(parse_object(new_sha1), NULL, 0);
1668        if (!o || o->type != OBJ_COMMIT)
1669                return 0;
1670        new = (struct commit *) o;
1671
1672        if (parse_commit(new) < 0)
1673                return 0;
1674
1675        used = list = NULL;
1676        commit_list_insert(new, &list);
1677        while (list) {
1678                new = pop_most_recent_commit(&list, TMP_MARK);
1679                commit_list_insert(new, &used);
1680                if (new == old) {
1681                        found = 1;
1682                        break;
1683                }
1684        }
1685        unmark_and_free(list, TMP_MARK);
1686        unmark_and_free(used, TMP_MARK);
1687        return found;
1688}
1689
1690/*
1691 * Return true if there is anything to report, otherwise false.
1692 */
1693int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
1694{
1695        unsigned char sha1[20];
1696        struct commit *ours, *theirs;
1697        char symmetric[84];
1698        struct rev_info revs;
1699        const char *rev_argv[10], *base;
1700        int rev_argc;
1701
1702        /*
1703         * Nothing to report unless we are marked to build on top of
1704         * somebody else.
1705         */
1706        if (!branch ||
1707            !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
1708                return 0;
1709
1710        /*
1711         * If what we used to build on no longer exists, there is
1712         * nothing to report.
1713         */
1714        base = branch->merge[0]->dst;
1715        if (read_ref(base, sha1))
1716                return 0;
1717        theirs = lookup_commit_reference(sha1);
1718        if (!theirs)
1719                return 0;
1720
1721        if (read_ref(branch->refname, sha1))
1722                return 0;
1723        ours = lookup_commit_reference(sha1);
1724        if (!ours)
1725                return 0;
1726
1727        /* are we the same? */
1728        if (theirs == ours)
1729                return 0;
1730
1731        /* Run "rev-list --left-right ours...theirs" internally... */
1732        rev_argc = 0;
1733        rev_argv[rev_argc++] = NULL;
1734        rev_argv[rev_argc++] = "--left-right";
1735        rev_argv[rev_argc++] = symmetric;
1736        rev_argv[rev_argc++] = "--";
1737        rev_argv[rev_argc] = NULL;
1738
1739        strcpy(symmetric, sha1_to_hex(ours->object.sha1));
1740        strcpy(symmetric + 40, "...");
1741        strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
1742
1743        init_revisions(&revs, NULL);
1744        setup_revisions(rev_argc, rev_argv, &revs, NULL);
1745        prepare_revision_walk(&revs);
1746
1747        /* ... and count the commits on each side. */
1748        *num_ours = 0;
1749        *num_theirs = 0;
1750        while (1) {
1751                struct commit *c = get_revision(&revs);
1752                if (!c)
1753                        break;
1754                if (c->object.flags & SYMMETRIC_LEFT)
1755                        (*num_ours)++;
1756                else
1757                        (*num_theirs)++;
1758        }
1759
1760        /* clear object flags smudged by the above traversal */
1761        clear_commit_marks(ours, ALL_REV_FLAGS);
1762        clear_commit_marks(theirs, ALL_REV_FLAGS);
1763        return 1;
1764}
1765
1766/*
1767 * Return true when there is anything to report, otherwise false.
1768 */
1769int format_tracking_info(struct branch *branch, struct strbuf *sb)
1770{
1771        int num_ours, num_theirs;
1772        const char *base;
1773
1774        if (!stat_tracking_info(branch, &num_ours, &num_theirs))
1775                return 0;
1776
1777        base = branch->merge[0]->dst;
1778        base = shorten_unambiguous_ref(base, 0);
1779        if (!num_theirs) {
1780                strbuf_addf(sb,
1781                        Q_("Your branch is ahead of '%s' by %d commit.\n",
1782                           "Your branch is ahead of '%s' by %d commits.\n",
1783                           num_ours),
1784                        base, num_ours);
1785                if (advice_status_hints)
1786                        strbuf_addf(sb,
1787                                _("  (use \"git push\" to publish your local commits)\n"));
1788        } else if (!num_ours) {
1789                strbuf_addf(sb,
1790                        Q_("Your branch is behind '%s' by %d commit, "
1791                               "and can be fast-forwarded.\n",
1792                           "Your branch is behind '%s' by %d commits, "
1793                               "and can be fast-forwarded.\n",
1794                           num_theirs),
1795                        base, num_theirs);
1796                if (advice_status_hints)
1797                        strbuf_addf(sb,
1798                                _("  (use \"git pull\" to update your local branch)\n"));
1799        } else {
1800                strbuf_addf(sb,
1801                        Q_("Your branch and '%s' have diverged,\n"
1802                               "and have %d and %d different commit each, "
1803                               "respectively.\n",
1804                           "Your branch and '%s' have diverged,\n"
1805                               "and have %d and %d different commits each, "
1806                               "respectively.\n",
1807                           num_theirs),
1808                        base, num_ours, num_theirs);
1809                if (advice_status_hints)
1810                        strbuf_addf(sb,
1811                                _("  (use \"git pull\" to merge the remote branch into yours)\n"));
1812        }
1813        return 1;
1814}
1815
1816static int one_local_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
1817{
1818        struct ref ***local_tail = cb_data;
1819        struct ref *ref;
1820        int len;
1821
1822        /* we already know it starts with refs/ to get here */
1823        if (check_refname_format(refname + 5, 0))
1824                return 0;
1825
1826        len = strlen(refname) + 1;
1827        ref = xcalloc(1, sizeof(*ref) + len);
1828        hashcpy(ref->new_sha1, sha1);
1829        memcpy(ref->name, refname, len);
1830        **local_tail = ref;
1831        *local_tail = &ref->next;
1832        return 0;
1833}
1834
1835struct ref *get_local_heads(void)
1836{
1837        struct ref *local_refs = NULL, **local_tail = &local_refs;
1838        for_each_ref(one_local_ref, &local_tail);
1839        return local_refs;
1840}
1841
1842struct ref *guess_remote_head(const struct ref *head,
1843                              const struct ref *refs,
1844                              int all)
1845{
1846        const struct ref *r;
1847        struct ref *list = NULL;
1848        struct ref **tail = &list;
1849
1850        if (!head)
1851                return NULL;
1852
1853        /*
1854         * Some transports support directly peeking at
1855         * where HEAD points; if that is the case, then
1856         * we don't have to guess.
1857         */
1858        if (head->symref)
1859                return copy_ref(find_ref_by_name(refs, head->symref));
1860
1861        /* If refs/heads/master could be right, it is. */
1862        if (!all) {
1863                r = find_ref_by_name(refs, "refs/heads/master");
1864                if (r && !hashcmp(r->old_sha1, head->old_sha1))
1865                        return copy_ref(r);
1866        }
1867
1868        /* Look for another ref that points there */
1869        for (r = refs; r; r = r->next) {
1870                if (r != head &&
1871                    !prefixcmp(r->name, "refs/heads/") &&
1872                    !hashcmp(r->old_sha1, head->old_sha1)) {
1873                        *tail = copy_ref(r);
1874                        tail = &((*tail)->next);
1875                        if (!all)
1876                                break;
1877                }
1878        }
1879
1880        return list;
1881}
1882
1883struct stale_heads_info {
1884        struct string_list *ref_names;
1885        struct ref **stale_refs_tail;
1886        struct refspec *refs;
1887        int ref_count;
1888};
1889
1890static int get_stale_heads_cb(const char *refname,
1891        const unsigned char *sha1, int flags, void *cb_data)
1892{
1893        struct stale_heads_info *info = cb_data;
1894        struct refspec query;
1895        memset(&query, 0, sizeof(struct refspec));
1896        query.dst = (char *)refname;
1897
1898        if (query_refspecs(info->refs, info->ref_count, &query))
1899                return 0; /* No matches */
1900
1901        /*
1902         * If we did find a suitable refspec and it's not a symref and
1903         * it's not in the list of refs that currently exist in that
1904         * remote we consider it to be stale.
1905         */
1906        if (!((flags & REF_ISSYMREF) ||
1907              string_list_has_string(info->ref_names, query.src))) {
1908                struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
1909                hashcpy(ref->new_sha1, sha1);
1910        }
1911
1912        free(query.src);
1913        return 0;
1914}
1915
1916struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fetch_map)
1917{
1918        struct ref *ref, *stale_refs = NULL;
1919        struct string_list ref_names = STRING_LIST_INIT_NODUP;
1920        struct stale_heads_info info;
1921        info.ref_names = &ref_names;
1922        info.stale_refs_tail = &stale_refs;
1923        info.refs = refs;
1924        info.ref_count = ref_count;
1925        for (ref = fetch_map; ref; ref = ref->next)
1926                string_list_append(&ref_names, ref->name);
1927        sort_string_list(&ref_names);
1928        for_each_ref(get_stale_heads_cb, &info);
1929        string_list_clear(&ref_names, 0);
1930        return stale_refs;
1931}