remote.c

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