remote.c

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