git.oblomov.eu Git - git/blob - remote.c

   1 #include "cache.h"
   2 #include "remote.h"
   3 #include "refs.h"
   4
   5 static struct refspec s_tag_refspec = {
   6         0,
   7         1,
   8         0,
   9         "refs/tags/",
  10         "refs/tags/"
  11 };
  12
  13 const struct refspec *tag_refspec = &s_tag_refspec;
  14
  15 struct counted_string {
  16         size_t len;
  17         const char *s;
  18 };
  19 struct rewrite {
  20         const char *base;
  21         size_t baselen;
  22         struct counted_string *instead_of;
  23         int instead_of_nr;
  24         int instead_of_alloc;
  25 };
  26
  27 static struct remote **remotes;
  28 static int remotes_alloc;
  29 static int remotes_nr;
  30
  31 static struct branch **branches;
  32 static int branches_alloc;
  33 static int branches_nr;
  34
  35 static struct branch *current_branch;
  36 static const char *default_remote_name;
  37
  38 static struct rewrite **rewrite;
  39 static int rewrite_alloc;
  40 static int rewrite_nr;
  41
  42 #define BUF_SIZE (2048)
  43 static char buffer[BUF_SIZE];
  44
  45 static const char *alias_url(const char *url)
  46 {
  47         int i, j;
  48         char *ret;
  49         struct counted_string *longest;
  50         int longest_i;
  51
  52         longest = NULL;
  53         longest_i = -1;
  54         for (i = 0; i < rewrite_nr; i++) {
  55                 if (!rewrite[i])
  56                         continue;
  57                 for (j = 0; j < rewrite[i]->instead_of_nr; j++) {
  58                         if (!prefixcmp(url, rewrite[i]->instead_of[j].s) &&
  59                             (!longest ||
  60                              longest->len < rewrite[i]->instead_of[j].len)) {
  61                                 longest = &(rewrite[i]->instead_of[j]);
  62                                 longest_i = i;
  63                         }
  64                 }
  65         }
  66         if (!longest)
  67                 return url;
  68
  69         ret = malloc(rewrite[longest_i]->baselen +
  70                      (strlen(url) - longest->len) + 1);
  71         strcpy(ret, rewrite[longest_i]->base);
  72         strcpy(ret + rewrite[longest_i]->baselen, url + longest->len);
  73         return ret;
  74 }
  75
  76 static void add_push_refspec(struct remote *remote, const char *ref)
  77 {
  78         ALLOC_GROW(remote->push_refspec,
  79                    remote->push_refspec_nr + 1,
  80                    remote->push_refspec_alloc);
  81         remote->push_refspec[remote->push_refspec_nr++] = ref;
  82 }
  83
  84 static void add_fetch_refspec(struct remote *remote, const char *ref)
  85 {
  86         ALLOC_GROW(remote->fetch_refspec,
  87                    remote->fetch_refspec_nr + 1,
  88                    remote->fetch_refspec_alloc);
  89         remote->fetch_refspec[remote->fetch_refspec_nr++] = ref;
  90 }
  91
  92 static void add_url(struct remote *remote, const char *url)
  93 {
  94         ALLOC_GROW(remote->url, remote->url_nr + 1, remote->url_alloc);
  95         remote->url[remote->url_nr++] = url;
  96 }
  97
  98 static void add_url_alias(struct remote *remote, const char *url)
  99 {
 100         add_url(remote, alias_url(url));
 101 }
 102
 103 static struct remote *make_remote(const char *name, int len)
 104 {
 105         struct remote *ret;
 106         int i;
 107
 108         for (i = 0; i < remotes_nr; i++) {
 109                 if (len ? (!strncmp(name, remotes[i]->name, len) &&
 110                            !remotes[i]->name[len]) :
 111                     !strcmp(name, remotes[i]->name))
 112                         return remotes[i];
 113         }
 114
 115         ret = xcalloc(1, sizeof(struct remote));
 116         ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 117         remotes[remotes_nr++] = ret;
 118         if (len)
 119                 ret->name = xstrndup(name, len);
 120         else
 121                 ret->name = xstrdup(name);
 122         return ret;
 123 }
 124
 125 static void add_merge(struct branch *branch, const char *name)
 126 {
 127         ALLOC_GROW(branch->merge_name, branch->merge_nr + 1,
 128                    branch->merge_alloc);
 129         branch->merge_name[branch->merge_nr++] = name;
 130 }
 131
 132 static struct branch *make_branch(const char *name, int len)
 133 {
 134         struct branch *ret;
 135         int i;
 136         char *refname;
 137
 138         for (i = 0; i < branches_nr; i++) {
 139                 if (len ? (!strncmp(name, branches[i]->name, len) &&
 140                            !branches[i]->name[len]) :
 141                     !strcmp(name, branches[i]->name))
 142                         return branches[i];
 143         }
 144
 145         ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 146         ret = xcalloc(1, sizeof(struct branch));
 147         branches[branches_nr++] = ret;
 148         if (len)
 149                 ret->name = xstrndup(name, len);
 150         else
 151                 ret->name = xstrdup(name);
 152         refname = malloc(strlen(name) + strlen("refs/heads/") + 1);
 153         strcpy(refname, "refs/heads/");
 154         strcpy(refname + strlen("refs/heads/"), ret->name);
 155         ret->refname = refname;
 156
 157         return ret;
 158 }
 159
 160 static struct rewrite *make_rewrite(const char *base, int len)
 161 {
 162         struct rewrite *ret;
 163         int i;
 164
 165         for (i = 0; i < rewrite_nr; i++) {
 166                 if (len
 167                     ? (len == rewrite[i]->baselen &&
 168                        !strncmp(base, rewrite[i]->base, len))
 169                     : !strcmp(base, rewrite[i]->base))
 170                         return rewrite[i];
 171         }
 172
 173         ALLOC_GROW(rewrite, rewrite_nr + 1, rewrite_alloc);
 174         ret = xcalloc(1, sizeof(struct rewrite));
 175         rewrite[rewrite_nr++] = ret;
 176         if (len) {
 177                 ret->base = xstrndup(base, len);
 178                 ret->baselen = len;
 179         }
 180         else {
 181                 ret->base = xstrdup(base);
 182                 ret->baselen = strlen(base);
 183         }
 184         return ret;
 185 }
 186
 187 static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 188 {
 189         ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 190         rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 191         rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 192         rewrite->instead_of_nr++;
 193 }
 194
 195 static void read_remotes_file(struct remote *remote)
 196 {
 197         FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
 198
 199         if (!f)
 200                 return;
 201         while (fgets(buffer, BUF_SIZE, f)) {
 202                 int value_list;
 203                 char *s, *p;
 204
 205                 if (!prefixcmp(buffer, "URL:")) {
 206                         value_list = 0;
 207                         s = buffer + 4;
 208                 } else if (!prefixcmp(buffer, "Push:")) {
 209                         value_list = 1;
 210                         s = buffer + 5;
 211                 } else if (!prefixcmp(buffer, "Pull:")) {
 212                         value_list = 2;
 213                         s = buffer + 5;
 214                 } else
 215                         continue;
 216
 217                 while (isspace(*s))
 218                         s++;
 219                 if (!*s)
 220                         continue;
 221
 222                 p = s + strlen(s);
 223                 while (isspace(p[-1]))
 224                         *--p = 0;
 225
 226                 switch (value_list) {
 227                 case 0:
 228                         add_url_alias(remote, xstrdup(s));
 229                         break;
 230                 case 1:
 231                         add_push_refspec(remote, xstrdup(s));
 232                         break;
 233                 case 2:
 234                         add_fetch_refspec(remote, xstrdup(s));
 235                         break;
 236                 }
 237         }
 238         fclose(f);
 239 }
 240
 241 static void read_branches_file(struct remote *remote)
 242 {
 243         const char *slash = strchr(remote->name, '/');
 244         char *frag;
 245         struct strbuf branch;
 246         int n = slash ? slash - remote->name : 1000;
 247         FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 248         char *s, *p;
 249         int len;
 250
 251         if (!f)
 252                 return;
 253         s = fgets(buffer, BUF_SIZE, f);
 254         fclose(f);
 255         if (!s)
 256                 return;
 257         while (isspace(*s))
 258                 s++;
 259         if (!*s)
 260                 return;
 261         p = s + strlen(s);
 262         while (isspace(p[-1]))
 263                 *--p = 0;
 264         len = p - s;
 265         if (slash)
 266                 len += strlen(slash);
 267         p = xmalloc(len + 1);
 268         strcpy(p, s);
 269         if (slash)
 270                 strcat(p, slash);
 271
 272         /*
 273          * With "slash", e.g. "git fetch jgarzik/netdev-2.6" when
 274          * reading from $GIT_DIR/branches/jgarzik fetches "HEAD" from
 275          * the partial URL obtained from the branches file plus
 276          * "/netdev-2.6" and does not store it in any tracking ref.
 277          * #branch specifier in the file is ignored.
 278          *
 279          * Otherwise, the branches file would have URL and optionally
 280          * #branch specified.  The "master" (or specified) branch is
 281          * fetched and stored in the local branch of the same name.
 282          */
 283         strbuf_init(&branch, 0);
 284         frag = strchr(p, '#');
 285         if (frag) {
 286                 *(frag++) = '\0';
 287                 strbuf_addf(&branch, "refs/heads/%s", frag);
 288         } else
 289                 strbuf_addstr(&branch, "refs/heads/master");
 290         if (!slash) {
 291                 strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 292         } else {
 293                 strbuf_reset(&branch);
 294                 strbuf_addstr(&branch, "HEAD:");
 295         }
 296         add_url_alias(remote, p);
 297         add_fetch_refspec(remote, strbuf_detach(&branch, 0));
 298         remote->fetch_tags = 1; /* always auto-follow */
 299 }
 300
 301 static int handle_config(const char *key, const char *value, void *cb)
 302 {
 303         const char *name;
 304         const char *subkey;
 305         struct remote *remote;
 306         struct branch *branch;
 307         if (!prefixcmp(key, "branch.")) {
 308                 name = key + 7;
 309                 subkey = strrchr(name, '.');
 310                 if (!subkey)
 311                         return 0;
 312                 branch = make_branch(name, subkey - name);
 313                 if (!strcmp(subkey, ".remote")) {
 314                         if (!value)
 315                                 return config_error_nonbool(key);
 316                         branch->remote_name = xstrdup(value);
 317                         if (branch == current_branch)
 318                                 default_remote_name = branch->remote_name;
 319                 } else if (!strcmp(subkey, ".merge")) {
 320                         if (!value)
 321                                 return config_error_nonbool(key);
 322                         add_merge(branch, xstrdup(value));
 323                 }
 324                 return 0;
 325         }
 326         if (!prefixcmp(key, "url.")) {
 327                 struct rewrite *rewrite;
 328                 name = key + 4;
 329                 subkey = strrchr(name, '.');
 330                 if (!subkey)
 331                         return 0;
 332                 rewrite = make_rewrite(name, subkey - name);
 333                 if (!strcmp(subkey, ".insteadof")) {
 334                         if (!value)
 335                                 return config_error_nonbool(key);
 336                         add_instead_of(rewrite, xstrdup(value));
 337                 }
 338         }
 339         if (prefixcmp(key,  "remote."))
 340                 return 0;
 341         name = key + 7;
 342         subkey = strrchr(name, '.');
 343         if (!subkey)
 344                 return error("Config with no key for remote %s", name);
 345         if (*subkey == '/') {
 346                 warning("Config remote shorthand cannot begin with '/': %s", name);
 347                 return 0;
 348         }
 349         remote = make_remote(name, subkey - name);
 350         if (!strcmp(subkey, ".mirror"))
 351                 remote->mirror = git_config_bool(key, value);
 352         else if (!strcmp(subkey, ".skipdefaultupdate"))
 353                 remote->skip_default_update = git_config_bool(key, value);
 354
 355         else if (!strcmp(subkey, ".url")) {
 356                 const char *v;
 357                 if (git_config_string(&v, key, value))
 358                         return -1;
 359                 add_url(remote, v);
 360         } else if (!strcmp(subkey, ".push")) {
 361                 const char *v;
 362                 if (git_config_string(&v, key, value))
 363                         return -1;
 364                 add_push_refspec(remote, v);
 365         } else if (!strcmp(subkey, ".fetch")) {
 366                 const char *v;
 367                 if (git_config_string(&v, key, value))
 368                         return -1;
 369                 add_fetch_refspec(remote, v);
 370         } else if (!strcmp(subkey, ".receivepack")) {
 371                 const char *v;
 372                 if (git_config_string(&v, key, value))
 373                         return -1;
 374                 if (!remote->receivepack)
 375                         remote->receivepack = v;
 376                 else
 377                         error("more than one receivepack given, using the first");
 378         } else if (!strcmp(subkey, ".uploadpack")) {
 379                 const char *v;
 380                 if (git_config_string(&v, key, value))
 381                         return -1;
 382                 if (!remote->uploadpack)
 383                         remote->uploadpack = v;
 384                 else
 385                         error("more than one uploadpack given, using the first");
 386         } else if (!strcmp(subkey, ".tagopt")) {
 387                 if (!strcmp(value, "--no-tags"))
 388                         remote->fetch_tags = -1;
 389         } else if (!strcmp(subkey, ".proxy")) {
 390                 return git_config_string((const char **)&remote->http_proxy,
 391                                          key, value);
 392         }
 393         return 0;
 394 }
 395
 396 static void alias_all_urls(void)
 397 {
 398         int i, j;
 399         for (i = 0; i < remotes_nr; i++) {
 400                 if (!remotes[i])
 401                         continue;
 402                 for (j = 0; j < remotes[i]->url_nr; j++) {
 403                         remotes[i]->url[j] = alias_url(remotes[i]->url[j]);
 404                 }
 405         }
 406 }
 407
 408 static void read_config(void)
 409 {
 410         unsigned char sha1[20];
 411         const char *head_ref;
 412         int flag;
 413         if (default_remote_name) // did this already
 414                 return;
 415         default_remote_name = xstrdup("origin");
 416         current_branch = NULL;
 417         head_ref = resolve_ref("HEAD", sha1, 0, &flag);
 418         if (head_ref && (flag & REF_ISSYMREF) &&
 419             !prefixcmp(head_ref, "refs/heads/")) {
 420                 current_branch =
 421                         make_branch(head_ref + strlen("refs/heads/"), 0);
 422         }
 423         git_config(handle_config, NULL);
 424         alias_all_urls();
 425 }
 426
 427 /*
 428  * We need to make sure the tracking branches are well formed, but a
 429  * wildcard refspec in "struct refspec" must have a trailing slash. We
 430  * temporarily drop the trailing '/' while calling check_ref_format(),
 431  * and put it back.  The caller knows that a CHECK_REF_FORMAT_ONELEVEL
 432  * error return is Ok for a wildcard refspec.
 433  */
 434 static int verify_refname(char *name, int is_glob)
 435 {
 436         int result, len = -1;
 437
 438         if (is_glob) {
 439                 len = strlen(name);
 440                 assert(name[len - 1] == '/');
 441                 name[len - 1] = '\0';
 442         }
 443         result = check_ref_format(name);
 444         if (is_glob)
 445                 name[len - 1] = '/';
 446         return result;
 447 }
 448
 449 static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 450 {
 451         int i;
 452         int st;
 453         struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 454
 455         for (i = 0; i < nr_refspec; i++) {
 456                 size_t llen;
 457                 int is_glob;
 458                 const char *lhs, *rhs;
 459
 460                 llen = is_glob = 0;
 461
 462                 lhs = refspec[i];
 463                 if (*lhs == '+') {
 464                         rs[i].force = 1;
 465                         lhs++;
 466                 }
 467
 468                 rhs = strrchr(lhs, ':');
 469
 470                 /*
 471                  * Before going on, special case ":" (or "+:") as a refspec
 472                  * for matching refs.
 473                  */
 474                 if (!fetch && rhs == lhs && rhs[1] == '\0') {
 475                         rs[i].matching = 1;
 476                         continue;
 477                 }
 478
 479                 if (rhs) {
 480                         size_t rlen = strlen(++rhs);
 481                         is_glob = (2 <= rlen && !strcmp(rhs + rlen - 2, "/*"));
 482                         rs[i].dst = xstrndup(rhs, rlen - is_glob);
 483                 }
 484
 485                 llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 486                 if (2 <= llen && !memcmp(lhs + llen - 2, "/*", 2)) {
 487                         if ((rhs && !is_glob) || (!rhs && fetch))
 488                                 goto invalid;
 489                         is_glob = 1;
 490                         llen--;
 491                 } else if (rhs && is_glob) {
 492                         goto invalid;
 493                 }
 494
 495                 rs[i].pattern = is_glob;
 496                 rs[i].src = xstrndup(lhs, llen);
 497
 498                 if (fetch) {
 499                         /*
 500                          * LHS
 501                          * - empty is allowed; it means HEAD.
 502                          * - otherwise it must be a valid looking ref.
 503                          */
 504                         if (!*rs[i].src)
 505                                 ; /* empty is ok */
 506                         else {
 507                                 st = verify_refname(rs[i].src, is_glob);
 508                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 509                                         goto invalid;
 510                         }
 511                         /*
 512                          * RHS
 513                          * - missing is ok, and is same as empty.
 514                          * - empty is ok; it means not to store.
 515                          * - otherwise it must be a valid looking ref.
 516                          */
 517                         if (!rs[i].dst) {
 518                                 ; /* ok */
 519                         } else if (!*rs[i].dst) {
 520                                 ; /* ok */
 521                         } else {
 522                                 st = verify_refname(rs[i].dst, is_glob);
 523                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 524                                         goto invalid;
 525                         }
 526                 } else {
 527                         /*
 528                          * LHS
 529                          * - empty is allowed; it means delete.
 530                          * - when wildcarded, it must be a valid looking ref.
 531                          * - otherwise, it must be an extended SHA-1, but
 532                          *   there is no existing way to validate this.
 533                          */
 534                         if (!*rs[i].src)
 535                                 ; /* empty is ok */
 536                         else if (is_glob) {
 537                                 st = verify_refname(rs[i].src, is_glob);
 538                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 539                                         goto invalid;
 540                         }
 541                         else
 542                                 ; /* anything goes, for now */
 543                         /*
 544                          * RHS
 545                          * - missing is allowed, but LHS then must be a
 546                          *   valid looking ref.
 547                          * - empty is not allowed.
 548                          * - otherwise it must be a valid looking ref.
 549                          */
 550                         if (!rs[i].dst) {
 551                                 st = verify_refname(rs[i].src, is_glob);
 552                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 553                                         goto invalid;
 554                         } else if (!*rs[i].dst) {
 555                                 goto invalid;
 556                         } else {
 557                                 st = verify_refname(rs[i].dst, is_glob);
 558                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 559                                         goto invalid;
 560                         }
 561                 }
 562         }
 563         return rs;
 564
 565  invalid:
 566         if (verify) {
 567                 free(rs);
 568                 return NULL;
 569         }
 570         die("Invalid refspec '%s'", refspec[i]);
 571 }
 572
 573 int valid_fetch_refspec(const char *fetch_refspec_str)
 574 {
 575         const char *fetch_refspec[] = { fetch_refspec_str };
 576         struct refspec *refspec;
 577
 578         refspec = parse_refspec_internal(1, fetch_refspec, 1, 1);
 579         if (refspec)
 580                 free(refspec);
 581         return !!refspec;
 582 }
 583
 584 struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 585 {
 586         return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 587 }
 588
 589 struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 590 {
 591         return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 592 }
 593
 594 static int valid_remote_nick(const char *name)
 595 {
 596         if (!name[0] || /* not empty */
 597             (name[0] == '.' && /* not "." */
 598              (!name[1] || /* not ".." */
 599               (name[1] == '.' && !name[2]))))
 600                 return 0;
 601         return !strchr(name, '/'); /* no slash */
 602 }
 603
 604 struct remote *remote_get(const char *name)
 605 {
 606         struct remote *ret;
 607
 608         read_config();
 609         if (!name)
 610                 name = default_remote_name;
 611         ret = make_remote(name, 0);
 612         if (valid_remote_nick(name)) {
 613                 if (!ret->url)
 614                         read_remotes_file(ret);
 615                 if (!ret->url)
 616                         read_branches_file(ret);
 617         }
 618         if (!ret->url)
 619                 add_url_alias(ret, name);
 620         if (!ret->url)
 621                 return NULL;
 622         ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 623         ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 624         return ret;
 625 }
 626
 627 int for_each_remote(each_remote_fn fn, void *priv)
 628 {
 629         int i, result = 0;
 630         read_config();
 631         for (i = 0; i < remotes_nr && !result; i++) {
 632                 struct remote *r = remotes[i];
 633                 if (!r)
 634                         continue;
 635                 if (!r->fetch)
 636                         r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 637                                                        r->fetch_refspec);
 638                 if (!r->push)
 639                         r->push = parse_push_refspec(r->push_refspec_nr,
 640                                                      r->push_refspec);
 641                 result = fn(r, priv);
 642         }
 643         return result;
 644 }
 645
 646 void ref_remove_duplicates(struct ref *ref_map)
 647 {
 648         struct ref **posn;
 649         struct ref *next;
 650         for (; ref_map; ref_map = ref_map->next) {
 651                 if (!ref_map->peer_ref)
 652                         continue;
 653                 posn = &ref_map->next;
 654                 while (*posn) {
 655                         if ((*posn)->peer_ref &&
 656                             !strcmp((*posn)->peer_ref->name,
 657                                     ref_map->peer_ref->name)) {
 658                                 if (strcmp((*posn)->name, ref_map->name))
 659                                         die("%s tracks both %s and %s",
 660                                             ref_map->peer_ref->name,
 661                                             (*posn)->name, ref_map->name);
 662                                 next = (*posn)->next;
 663                                 free((*posn)->peer_ref);
 664                                 free(*posn);
 665                                 *posn = next;
 666                         } else {
 667                                 posn = &(*posn)->next;
 668                         }
 669                 }
 670         }
 671 }
 672
 673 int remote_has_url(struct remote *remote, const char *url)
 674 {
 675         int i;
 676         for (i = 0; i < remote->url_nr; i++) {
 677                 if (!strcmp(remote->url[i], url))
 678                         return 1;
 679         }
 680         return 0;
 681 }
 682
 683 int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 684 {
 685         int find_src = refspec->src == NULL;
 686         char *needle, **result;
 687         int i;
 688
 689         if (find_src) {
 690                 if (!refspec->dst)
 691                         return error("find_tracking: need either src or dst");
 692                 needle = refspec->dst;
 693                 result = &refspec->src;
 694         } else {
 695                 needle = refspec->src;
 696                 result = &refspec->dst;
 697         }
 698
 699         for (i = 0; i < remote->fetch_refspec_nr; i++) {
 700                 struct refspec *fetch = &remote->fetch[i];
 701                 const char *key = find_src ? fetch->dst : fetch->src;
 702                 const char *value = find_src ? fetch->src : fetch->dst;
 703                 if (!fetch->dst)
 704                         continue;
 705                 if (fetch->pattern) {
 706                         if (!prefixcmp(needle, key)) {
 707                                 *result = xmalloc(strlen(value) +
 708                                                   strlen(needle) -
 709                                                   strlen(key) + 1);
 710                                 strcpy(*result, value);
 711                                 strcpy(*result + strlen(value),
 712                                        needle + strlen(key));
 713                                 refspec->force = fetch->force;
 714                                 return 0;
 715                         }
 716                 } else if (!strcmp(needle, key)) {
 717                         *result = xstrdup(value);
 718                         refspec->force = fetch->force;
 719                         return 0;
 720                 }
 721         }
 722         return -1;
 723 }
 724
 725 struct ref *alloc_ref(unsigned namelen)
 726 {
 727         struct ref *ret = xmalloc(sizeof(struct ref) + namelen);
 728         memset(ret, 0, sizeof(struct ref) + namelen);
 729         return ret;
 730 }
 731
 732 struct ref *alloc_ref_from_str(const char* str)
 733 {
 734         struct ref *ret = alloc_ref(strlen(str) + 1);
 735         strcpy(ret->name, str);
 736         return ret;
 737 }
 738
 739 static struct ref *copy_ref(const struct ref *ref)
 740 {
 741         struct ref *ret = xmalloc(sizeof(struct ref) + strlen(ref->name) + 1);
 742         memcpy(ret, ref, sizeof(struct ref) + strlen(ref->name) + 1);
 743         ret->next = NULL;
 744         return ret;
 745 }
 746
 747 struct ref *copy_ref_list(const struct ref *ref)
 748 {
 749         struct ref *ret = NULL;
 750         struct ref **tail = &ret;
 751         while (ref) {
 752                 *tail = copy_ref(ref);
 753                 ref = ref->next;
 754                 tail = &((*tail)->next);
 755         }
 756         return ret;
 757 }
 758
 759 void free_ref(struct ref *ref)
 760 {
 761         if (!ref)
 762                 return;
 763         free(ref->remote_status);
 764         free(ref->symref);
 765         free(ref);
 766 }
 767
 768 void free_refs(struct ref *ref)
 769 {
 770         struct ref *next;
 771         while (ref) {
 772                 next = ref->next;
 773                 free(ref->peer_ref);
 774                 free_ref(ref);
 775                 ref = next;
 776         }
 777 }
 778
 779 static int count_refspec_match(const char *pattern,
 780                                struct ref *refs,
 781                                struct ref **matched_ref)
 782 {
 783         int patlen = strlen(pattern);
 784         struct ref *matched_weak = NULL;
 785         struct ref *matched = NULL;
 786         int weak_match = 0;
 787         int match = 0;
 788
 789         for (weak_match = match = 0; refs; refs = refs->next) {
 790                 char *name = refs->name;
 791                 int namelen = strlen(name);
 792
 793                 if (!refname_match(pattern, name, ref_rev_parse_rules))
 794                         continue;
 795
 796                 /* A match is "weak" if it is with refs outside
 797                  * heads or tags, and did not specify the pattern
 798                  * in full (e.g. "refs/remotes/origin/master") or at
 799                  * least from the toplevel (e.g. "remotes/origin/master");
 800                  * otherwise "git push $URL master" would result in
 801                  * ambiguity between remotes/origin/master and heads/master
 802                  * at the remote site.
 803                  */
 804                 if (namelen != patlen &&
 805                     patlen != namelen - 5 &&
 806                     prefixcmp(name, "refs/heads/") &&
 807                     prefixcmp(name, "refs/tags/")) {
 808                         /* We want to catch the case where only weak
 809                          * matches are found and there are multiple
 810                          * matches, and where more than one strong
 811                          * matches are found, as ambiguous.  One
 812                          * strong match with zero or more weak matches
 813                          * are acceptable as a unique match.
 814                          */
 815                         matched_weak = refs;
 816                         weak_match++;
 817                 }
 818                 else {
 819                         matched = refs;
 820                         match++;
 821                 }
 822         }
 823         if (!matched) {
 824                 *matched_ref = matched_weak;
 825                 return weak_match;
 826         }
 827         else {
 828                 *matched_ref = matched;
 829                 return match;
 830         }
 831 }
 832
 833 static void tail_link_ref(struct ref *ref, struct ref ***tail)
 834 {
 835         **tail = ref;
 836         while (ref->next)
 837                 ref = ref->next;
 838         *tail = &ref->next;
 839 }
 840
 841 static struct ref *try_explicit_object_name(const char *name)
 842 {
 843         unsigned char sha1[20];
 844         struct ref *ref;
 845
 846         if (!*name) {
 847                 ref = alloc_ref(20);
 848                 strcpy(ref->name, "(delete)");
 849                 hashclr(ref->new_sha1);
 850                 return ref;
 851         }
 852         if (get_sha1(name, sha1))
 853                 return NULL;
 854         ref = alloc_ref_from_str(name);
 855         hashcpy(ref->new_sha1, sha1);
 856         return ref;
 857 }
 858
 859 static struct ref *make_linked_ref(const char *name, struct ref ***tail)
 860 {
 861         struct ref *ret = alloc_ref_from_str(name);
 862         tail_link_ref(ret, tail);
 863         return ret;
 864 }
 865
 866 static char *guess_ref(const char *name, struct ref *peer)
 867 {
 868         struct strbuf buf = STRBUF_INIT;
 869         unsigned char sha1[20];
 870
 871         const char *r = resolve_ref(peer->name, sha1, 1, NULL);
 872         if (!r)
 873                 return NULL;
 874
 875         if (!prefixcmp(r, "refs/heads/"))
 876                 strbuf_addstr(&buf, "refs/heads/");
 877         else if (!prefixcmp(r, "refs/tags/"))
 878                 strbuf_addstr(&buf, "refs/tags/");
 879         else
 880                 return NULL;
 881
 882         strbuf_addstr(&buf, name);
 883         return strbuf_detach(&buf, NULL);
 884 }
 885
 886 static int match_explicit(struct ref *src, struct ref *dst,
 887                           struct ref ***dst_tail,
 888                           struct refspec *rs)
 889 {
 890         struct ref *matched_src, *matched_dst;
 891
 892         const char *dst_value = rs->dst;
 893         char *dst_guess;
 894
 895         if (rs->pattern || rs->matching)
 896                 return 0;
 897
 898         matched_src = matched_dst = NULL;
 899         switch (count_refspec_match(rs->src, src, &matched_src)) {
 900         case 1:
 901                 break;
 902         case 0:
 903                 /* The source could be in the get_sha1() format
 904                  * not a reference name.  :refs/other is a
 905                  * way to delete 'other' ref at the remote end.
 906                  */
 907                 matched_src = try_explicit_object_name(rs->src);
 908                 if (!matched_src)
 909                         return error("src refspec %s does not match any.", rs->src);
 910                 break;
 911         default:
 912                 return error("src refspec %s matches more than one.", rs->src);
 913         }
 914
 915         if (!dst_value) {
 916                 unsigned char sha1[20];
 917                 int flag;
 918
 919                 dst_value = resolve_ref(matched_src->name, sha1, 1, &flag);
 920                 if (!dst_value ||
 921                     ((flag & REF_ISSYMREF) &&
 922                      prefixcmp(dst_value, "refs/heads/")))
 923                         die("%s cannot be resolved to branch.",
 924                             matched_src->name);
 925         }
 926
 927         switch (count_refspec_match(dst_value, dst, &matched_dst)) {
 928         case 1:
 929                 break;
 930         case 0:
 931                 if (!memcmp(dst_value, "refs/", 5))
 932                         matched_dst = make_linked_ref(dst_value, dst_tail);
 933                 else if((dst_guess = guess_ref(dst_value, matched_src)))
 934                         matched_dst = make_linked_ref(dst_guess, dst_tail);
 935                 else
 936                         error("unable to push to unqualified destination: %s\n"
 937                               "The destination refspec neither matches an "
 938                               "existing ref on the remote nor\n"
 939                               "begins with refs/, and we are unable to "
 940                               "guess a prefix based on the source ref.",
 941                               dst_value);
 942                 break;
 943         default:
 944                 matched_dst = NULL;
 945                 error("dst refspec %s matches more than one.",
 946                       dst_value);
 947                 break;
 948         }
 949         if (!matched_dst)
 950                 return -1;
 951         if (matched_dst->peer_ref)
 952                 return error("dst ref %s receives from more than one src.",
 953                       matched_dst->name);
 954         else {
 955                 matched_dst->peer_ref = matched_src;
 956                 matched_dst->force = rs->force;
 957         }
 958         return 0;
 959 }
 960
 961 static int match_explicit_refs(struct ref *src, struct ref *dst,
 962                                struct ref ***dst_tail, struct refspec *rs,
 963                                int rs_nr)
 964 {
 965         int i, errs;
 966         for (i = errs = 0; i < rs_nr; i++)
 967                 errs += match_explicit(src, dst, dst_tail, &rs[i]);
 968         return errs;
 969 }
 970
 971 static const struct refspec *check_pattern_match(const struct refspec *rs,
 972                                                  int rs_nr,
 973                                                  const struct ref *src)
 974 {
 975         int i;
 976         int matching_refs = -1;
 977         for (i = 0; i < rs_nr; i++) {
 978                 if (rs[i].matching &&
 979                     (matching_refs == -1 || rs[i].force)) {
 980                         matching_refs = i;
 981                         continue;
 982                 }
 983
 984                 if (rs[i].pattern && !prefixcmp(src->name, rs[i].src))
 985                         return rs + i;
 986         }
 987         if (matching_refs != -1)
 988                 return rs + matching_refs;
 989         else
 990                 return NULL;
 991 }
 992
 993 /*
 994  * Note. This is used only by "push"; refspec matching rules for
 995  * push and fetch are subtly different, so do not try to reuse it
 996  * without thinking.
 997  */
 998 int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 999                int nr_refspec, const char **refspec, int flags)
1000 {
1001         struct refspec *rs;
1002         int send_all = flags & MATCH_REFS_ALL;
1003         int send_mirror = flags & MATCH_REFS_MIRROR;
1004         static const char *default_refspec[] = { ":", 0 };
1005
1006         if (!nr_refspec) {
1007                 nr_refspec = 1;
1008                 refspec = default_refspec;
1009         }
1010         rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1011         if (match_explicit_refs(src, dst, dst_tail, rs, nr_refspec))
1012                 return -1;
1013
1014         /* pick the remainder */
1015         for ( ; src; src = src->next) {
1016                 struct ref *dst_peer;
1017                 const struct refspec *pat = NULL;
1018                 char *dst_name;
1019                 if (src->peer_ref)
1020                         continue;
1021
1022                 pat = check_pattern_match(rs, nr_refspec, src);
1023                 if (!pat)
1024                         continue;
1025
1026                 if (pat->matching) {
1027                         /*
1028                          * "matching refs"; traditionally we pushed everything
1029                          * including refs outside refs/heads/ hierarchy, but
1030                          * that does not make much sense these days.
1031                          */
1032                         if (!send_mirror && prefixcmp(src->name, "refs/heads/"))
1033                                 continue;
1034                         dst_name = xstrdup(src->name);
1035
1036                 } else {
1037                         const char *dst_side = pat->dst ? pat->dst : pat->src;
1038                         dst_name = xmalloc(strlen(dst_side) +
1039                                            strlen(src->name) -
1040                                            strlen(pat->src) + 2);
1041                         strcpy(dst_name, dst_side);
1042                         strcat(dst_name, src->name + strlen(pat->src));
1043                 }
1044                 dst_peer = find_ref_by_name(dst, dst_name);
1045                 if (dst_peer) {
1046                         if (dst_peer->peer_ref)
1047                                 /* We're already sending something to this ref. */
1048                                 goto free_name;
1049
1050                 } else {
1051                         if (pat->matching && !(send_all || send_mirror))
1052                                 /*
1053                                  * Remote doesn't have it, and we have no
1054                                  * explicit pattern, and we don't have
1055                                  * --all nor --mirror.
1056                                  */
1057                                 goto free_name;
1058
1059                         /* Create a new one and link it */
1060                         dst_peer = make_linked_ref(dst_name, dst_tail);
1061                         hashcpy(dst_peer->new_sha1, src->new_sha1);
1062                 }
1063                 dst_peer->peer_ref = src;
1064                 dst_peer->force = pat->force;
1065         free_name:
1066                 free(dst_name);
1067         }
1068         return 0;
1069 }
1070
1071 struct branch *branch_get(const char *name)
1072 {
1073         struct branch *ret;
1074
1075         read_config();
1076         if (!name || !*name || !strcmp(name, "HEAD"))
1077                 ret = current_branch;
1078         else
1079                 ret = make_branch(name, 0);
1080         if (ret && ret->remote_name) {
1081                 ret->remote = remote_get(ret->remote_name);
1082                 if (ret->merge_nr) {
1083                         int i;
1084                         ret->merge = xcalloc(sizeof(*ret->merge),
1085                                              ret->merge_nr);
1086                         for (i = 0; i < ret->merge_nr; i++) {
1087                                 ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1088                                 ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1089                                 remote_find_tracking(ret->remote,
1090                                                      ret->merge[i]);
1091                         }
1092                 }
1093         }
1094         return ret;
1095 }
1096
1097 int branch_has_merge_config(struct branch *branch)
1098 {
1099         return branch && !!branch->merge;
1100 }
1101
1102 int branch_merge_matches(struct branch *branch,
1103                                  int i,
1104                                  const char *refname)
1105 {
1106         if (!branch || i < 0 || i >= branch->merge_nr)
1107                 return 0;
1108         return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
1109 }
1110
1111 static struct ref *get_expanded_map(const struct ref *remote_refs,
1112                                     const struct refspec *refspec)
1113 {
1114         const struct ref *ref;
1115         struct ref *ret = NULL;
1116         struct ref **tail = &ret;
1117
1118         int remote_prefix_len = strlen(refspec->src);
1119         int local_prefix_len = strlen(refspec->dst);
1120
1121         for (ref = remote_refs; ref; ref = ref->next) {
1122                 if (strchr(ref->name, '^'))
1123                         continue; /* a dereference item */
1124                 if (!prefixcmp(ref->name, refspec->src)) {
1125                         const char *match;
1126                         struct ref *cpy = copy_ref(ref);
1127                         match = ref->name + remote_prefix_len;
1128
1129                         cpy->peer_ref = alloc_ref(local_prefix_len +
1130                                                   strlen(match) + 1);
1131                         sprintf(cpy->peer_ref->name, "%s%s",
1132                                 refspec->dst, match);
1133                         if (refspec->force)
1134                                 cpy->peer_ref->force = 1;
1135                         *tail = cpy;
1136                         tail = &cpy->next;
1137                 }
1138         }
1139
1140         return ret;
1141 }
1142
1143 static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1144 {
1145         const struct ref *ref;
1146         for (ref = refs; ref; ref = ref->next) {
1147                 if (refname_match(name, ref->name, ref_fetch_rules))
1148                         return ref;
1149         }
1150         return NULL;
1151 }
1152
1153 struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1154 {
1155         const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1156
1157         if (!ref)
1158                 return NULL;
1159
1160         return copy_ref(ref);
1161 }
1162
1163 static struct ref *get_local_ref(const char *name)
1164 {
1165         struct ref *ret;
1166         if (!name)
1167                 return NULL;
1168
1169         if (!prefixcmp(name, "refs/")) {
1170                 return alloc_ref_from_str(name);
1171         }
1172
1173         if (!prefixcmp(name, "heads/") ||
1174             !prefixcmp(name, "tags/") ||
1175             !prefixcmp(name, "remotes/")) {
1176                 ret = alloc_ref(strlen(name) + 6);
1177                 sprintf(ret->name, "refs/%s", name);
1178                 return ret;
1179         }
1180
1181         ret = alloc_ref(strlen(name) + 12);
1182         sprintf(ret->name, "refs/heads/%s", name);
1183         return ret;
1184 }
1185
1186 int get_fetch_map(const struct ref *remote_refs,
1187                   const struct refspec *refspec,
1188                   struct ref ***tail,
1189                   int missing_ok)
1190 {
1191         struct ref *ref_map, **rmp;
1192
1193         if (refspec->pattern) {
1194                 ref_map = get_expanded_map(remote_refs, refspec);
1195         } else {
1196                 const char *name = refspec->src[0] ? refspec->src : "HEAD";
1197
1198                 ref_map = get_remote_ref(remote_refs, name);
1199                 if (!missing_ok && !ref_map)
1200                         die("Couldn't find remote ref %s", name);
1201                 if (ref_map) {
1202                         ref_map->peer_ref = get_local_ref(refspec->dst);
1203                         if (ref_map->peer_ref && refspec->force)
1204                                 ref_map->peer_ref->force = 1;
1205                 }
1206         }
1207
1208         for (rmp = &ref_map; *rmp; ) {
1209                 if ((*rmp)->peer_ref) {
1210                         int st = check_ref_format((*rmp)->peer_ref->name + 5);
1211                         if (st && st != CHECK_REF_FORMAT_ONELEVEL) {
1212                                 struct ref *ignore = *rmp;
1213                                 error("* Ignoring funny ref '%s' locally",
1214                                       (*rmp)->peer_ref->name);
1215                                 *rmp = (*rmp)->next;
1216                                 free(ignore->peer_ref);
1217                                 free(ignore);
1218                                 continue;
1219                         }
1220                 }
1221                 rmp = &((*rmp)->next);
1222         }
1223
1224         if (ref_map)
1225                 tail_link_ref(ref_map, tail);
1226
1227         return 0;
1228 }
1229
1230 int resolve_remote_symref(struct ref *ref, struct ref *list)
1231 {
1232         if (!ref->symref)
1233                 return 0;
1234         for (; list; list = list->next)
1235                 if (!strcmp(ref->symref, list->name)) {
1236                         hashcpy(ref->old_sha1, list->old_sha1);
1237                         return 0;
1238                 }
1239         return 1;
1240 }