Pileus Git - ~andy/git/blob - remote.c

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