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 static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch)
 309 {
 310         int i;
 311         int st;
 312         struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 313
 314         for (i = 0; i < nr_refspec; i++) {
 315                 size_t llen, rlen;
 316                 int is_glob;
 317                 const char *lhs, *rhs;
 318
 319                 llen = rlen = is_glob = 0;
 320
 321                 lhs = refspec[i];
 322                 if (*lhs == '+') {
 323                         rs[i].force = 1;
 324                         lhs++;
 325                 }
 326
 327                 rhs = strrchr(lhs, ':');
 328                 if (rhs) {
 329                         rhs++;
 330                         rlen = strlen(rhs);
 331                         is_glob = (2 <= rlen && !strcmp(rhs + rlen - 2, "/*"));
 332                         if (is_glob)
 333                                 rlen -= 2;
 334                         rs[i].dst = xstrndup(rhs, rlen);
 335                 }
 336
 337                 llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 338                 if (2 <= llen && !memcmp(lhs + llen - 2, "/*", 2)) {
 339                         if ((rhs && !is_glob) || (!rhs && fetch))
 340                                 goto invalid;
 341                         is_glob = 1;
 342                         llen -= 2;
 343                 } else if (rhs && is_glob) {
 344                         goto invalid;
 345                 }
 346
 347                 rs[i].pattern = is_glob;
 348                 rs[i].src = xstrndup(lhs, llen);
 349
 350                 if (fetch) {
 351                         /*
 352                          * LHS
 353                          * - empty is allowed; it means HEAD.
 354                          * - otherwise it must be a valid looking ref.
 355                          */
 356                         if (!*rs[i].src)
 357                                 ; /* empty is ok */
 358                         else {
 359                                 st = check_ref_format(rs[i].src);
 360                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 361                                         goto invalid;
 362                         }
 363                         /*
 364                          * RHS
 365                          * - missing is ok, and is same as empty.
 366                          * - empty is ok; it means not to store.
 367                          * - otherwise it must be a valid looking ref.
 368                          */
 369                         if (!rs[i].dst) {
 370                                 ; /* ok */
 371                         } else if (!*rs[i].dst) {
 372                                 ; /* ok */
 373                         } else {
 374                                 st = check_ref_format(rs[i].dst);
 375                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 376                                         goto invalid;
 377                         }
 378                 } else {
 379                         /*
 380                          * LHS
 381                          * - empty is allowed; it means delete.
 382                          * - when wildcarded, it must be a valid looking ref.
 383                          * - otherwise, it must be an extended SHA-1, but
 384                          *   there is no existing way to validate this.
 385                          */
 386                         if (!*rs[i].src)
 387                                 ; /* empty is ok */
 388                         else if (is_glob) {
 389                                 st = check_ref_format(rs[i].src);
 390                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 391                                         goto invalid;
 392                         }
 393                         else
 394                                 ; /* anything goes, for now */
 395                         /*
 396                          * RHS
 397                          * - missing is allowed, but LHS then must be a
 398                          *   valid looking ref.
 399                          * - empty is not allowed.
 400                          * - otherwise it must be a valid looking ref.
 401                          */
 402                         if (!rs[i].dst) {
 403                                 st = check_ref_format(rs[i].src);
 404                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 405                                         goto invalid;
 406                         } else if (!*rs[i].dst) {
 407                                 goto invalid;
 408                         } else {
 409                                 st = check_ref_format(rs[i].dst);
 410                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 411                                         goto invalid;
 412                         }
 413                 }
 414         }
 415         return rs;
 416
 417  invalid:
 418         die("Invalid refspec '%s'", refspec[i]);
 419 }
 420
 421 struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 422 {
 423         return parse_refspec_internal(nr_refspec, refspec, 1);
 424 }
 425
 426 struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 427 {
 428         return parse_refspec_internal(nr_refspec, refspec, 0);
 429 }
 430
 431 static int valid_remote_nick(const char *name)
 432 {
 433         if (!name[0] || /* not empty */
 434             (name[0] == '.' && /* not "." */
 435              (!name[1] || /* not ".." */
 436               (name[1] == '.' && !name[2]))))
 437                 return 0;
 438         return !strchr(name, '/'); /* no slash */
 439 }
 440
 441 struct remote *remote_get(const char *name)
 442 {
 443         struct remote *ret;
 444
 445         read_config();
 446         if (!name)
 447                 name = default_remote_name;
 448         ret = make_remote(name, 0);
 449         if (valid_remote_nick(name)) {
 450                 if (!ret->url)
 451                         read_remotes_file(ret);
 452                 if (!ret->url)
 453                         read_branches_file(ret);
 454         }
 455         if (!ret->url)
 456                 add_url(ret, name);
 457         if (!ret->url)
 458                 return NULL;
 459         ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 460         ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 461         return ret;
 462 }
 463
 464 int for_each_remote(each_remote_fn fn, void *priv)
 465 {
 466         int i, result = 0;
 467         read_config();
 468         for (i = 0; i < allocated_remotes && !result; i++) {
 469                 struct remote *r = remotes[i];
 470                 if (!r)
 471                         continue;
 472                 if (!r->fetch)
 473                         r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 474                                                        r->fetch_refspec);
 475                 if (!r->push)
 476                         r->push = parse_push_refspec(r->push_refspec_nr,
 477                                                      r->push_refspec);
 478                 result = fn(r, priv);
 479         }
 480         return result;
 481 }
 482
 483 void ref_remove_duplicates(struct ref *ref_map)
 484 {
 485         struct ref **posn;
 486         struct ref *next;
 487         for (; ref_map; ref_map = ref_map->next) {
 488                 if (!ref_map->peer_ref)
 489                         continue;
 490                 posn = &ref_map->next;
 491                 while (*posn) {
 492                         if ((*posn)->peer_ref &&
 493                             !strcmp((*posn)->peer_ref->name,
 494                                     ref_map->peer_ref->name)) {
 495                                 if (strcmp((*posn)->name, ref_map->name))
 496                                         die("%s tracks both %s and %s",
 497                                             ref_map->peer_ref->name,
 498                                             (*posn)->name, ref_map->name);
 499                                 next = (*posn)->next;
 500                                 free((*posn)->peer_ref);
 501                                 free(*posn);
 502                                 *posn = next;
 503                         } else {
 504                                 posn = &(*posn)->next;
 505                         }
 506                 }
 507         }
 508 }
 509
 510 int remote_has_url(struct remote *remote, const char *url)
 511 {
 512         int i;
 513         for (i = 0; i < remote->url_nr; i++) {
 514                 if (!strcmp(remote->url[i], url))
 515                         return 1;
 516         }
 517         return 0;
 518 }
 519
 520 int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 521 {
 522         int find_src = refspec->src == NULL;
 523         char *needle, **result;
 524         int i;
 525
 526         if (find_src) {
 527                 if (!refspec->dst)
 528                         return error("find_tracking: need either src or dst");
 529                 needle = refspec->dst;
 530                 result = &refspec->src;
 531         } else {
 532                 needle = refspec->src;
 533                 result = &refspec->dst;
 534         }
 535
 536         for (i = 0; i < remote->fetch_refspec_nr; i++) {
 537                 struct refspec *fetch = &remote->fetch[i];
 538                 const char *key = find_src ? fetch->dst : fetch->src;
 539                 const char *value = find_src ? fetch->src : fetch->dst;
 540                 if (!fetch->dst)
 541                         continue;
 542                 if (fetch->pattern) {
 543                         if (!prefixcmp(needle, key) &&
 544                             needle[strlen(key)] == '/') {
 545                                 *result = xmalloc(strlen(value) +
 546                                                   strlen(needle) -
 547                                                   strlen(key) + 1);
 548                                 strcpy(*result, value);
 549                                 strcpy(*result + strlen(value),
 550                                        needle + strlen(key));
 551                                 refspec->force = fetch->force;
 552                                 return 0;
 553                         }
 554                 } else if (!strcmp(needle, key)) {
 555                         *result = xstrdup(value);
 556                         refspec->force = fetch->force;
 557                         return 0;
 558                 }
 559         }
 560         return -1;
 561 }
 562
 563 struct ref *alloc_ref(unsigned namelen)
 564 {
 565         struct ref *ret = xmalloc(sizeof(struct ref) + namelen);
 566         memset(ret, 0, sizeof(struct ref) + namelen);
 567         return ret;
 568 }
 569
 570 static struct ref *copy_ref(const struct ref *ref)
 571 {
 572         struct ref *ret = xmalloc(sizeof(struct ref) + strlen(ref->name) + 1);
 573         memcpy(ret, ref, sizeof(struct ref) + strlen(ref->name) + 1);
 574         ret->next = NULL;
 575         return ret;
 576 }
 577
 578 struct ref *copy_ref_list(const struct ref *ref)
 579 {
 580         struct ref *ret = NULL;
 581         struct ref **tail = &ret;
 582         while (ref) {
 583                 *tail = copy_ref(ref);
 584                 ref = ref->next;
 585                 tail = &((*tail)->next);
 586         }
 587         return ret;
 588 }
 589
 590 void free_refs(struct ref *ref)
 591 {
 592         struct ref *next;
 593         while (ref) {
 594                 next = ref->next;
 595                 if (ref->peer_ref)
 596                         free(ref->peer_ref);
 597                 free(ref);
 598                 ref = next;
 599         }
 600 }
 601
 602 static int count_refspec_match(const char *pattern,
 603                                struct ref *refs,
 604                                struct ref **matched_ref)
 605 {
 606         int patlen = strlen(pattern);
 607         struct ref *matched_weak = NULL;
 608         struct ref *matched = NULL;
 609         int weak_match = 0;
 610         int match = 0;
 611
 612         for (weak_match = match = 0; refs; refs = refs->next) {
 613                 char *name = refs->name;
 614                 int namelen = strlen(name);
 615
 616                 if (!refname_match(pattern, name, ref_rev_parse_rules))
 617                         continue;
 618
 619                 /* A match is "weak" if it is with refs outside
 620                  * heads or tags, and did not specify the pattern
 621                  * in full (e.g. "refs/remotes/origin/master") or at
 622                  * least from the toplevel (e.g. "remotes/origin/master");
 623                  * otherwise "git push $URL master" would result in
 624                  * ambiguity between remotes/origin/master and heads/master
 625                  * at the remote site.
 626                  */
 627                 if (namelen != patlen &&
 628                     patlen != namelen - 5 &&
 629                     prefixcmp(name, "refs/heads/") &&
 630                     prefixcmp(name, "refs/tags/")) {
 631                         /* We want to catch the case where only weak
 632                          * matches are found and there are multiple
 633                          * matches, and where more than one strong
 634                          * matches are found, as ambiguous.  One
 635                          * strong match with zero or more weak matches
 636                          * are acceptable as a unique match.
 637                          */
 638                         matched_weak = refs;
 639                         weak_match++;
 640                 }
 641                 else {
 642                         matched = refs;
 643                         match++;
 644                 }
 645         }
 646         if (!matched) {
 647                 *matched_ref = matched_weak;
 648                 return weak_match;
 649         }
 650         else {
 651                 *matched_ref = matched;
 652                 return match;
 653         }
 654 }
 655
 656 static void tail_link_ref(struct ref *ref, struct ref ***tail)
 657 {
 658         **tail = ref;
 659         while (ref->next)
 660                 ref = ref->next;
 661         *tail = &ref->next;
 662 }
 663
 664 static struct ref *try_explicit_object_name(const char *name)
 665 {
 666         unsigned char sha1[20];
 667         struct ref *ref;
 668         int len;
 669
 670         if (!*name) {
 671                 ref = alloc_ref(20);
 672                 strcpy(ref->name, "(delete)");
 673                 hashclr(ref->new_sha1);
 674                 return ref;
 675         }
 676         if (get_sha1(name, sha1))
 677                 return NULL;
 678         len = strlen(name) + 1;
 679         ref = alloc_ref(len);
 680         memcpy(ref->name, name, len);
 681         hashcpy(ref->new_sha1, sha1);
 682         return ref;
 683 }
 684
 685 static struct ref *make_linked_ref(const char *name, struct ref ***tail)
 686 {
 687         struct ref *ret;
 688         size_t len;
 689
 690         len = strlen(name) + 1;
 691         ret = alloc_ref(len);
 692         memcpy(ret->name, name, len);
 693         tail_link_ref(ret, tail);
 694         return ret;
 695 }
 696
 697 static int match_explicit(struct ref *src, struct ref *dst,
 698                           struct ref ***dst_tail,
 699                           struct refspec *rs,
 700                           int errs)
 701 {
 702         struct ref *matched_src, *matched_dst;
 703
 704         const char *dst_value = rs->dst;
 705
 706         if (rs->pattern)
 707                 return errs;
 708
 709         matched_src = matched_dst = NULL;
 710         switch (count_refspec_match(rs->src, src, &matched_src)) {
 711         case 1:
 712                 break;
 713         case 0:
 714                 /* The source could be in the get_sha1() format
 715                  * not a reference name.  :refs/other is a
 716                  * way to delete 'other' ref at the remote end.
 717                  */
 718                 matched_src = try_explicit_object_name(rs->src);
 719                 if (!matched_src)
 720                         error("src refspec %s does not match any.", rs->src);
 721                 break;
 722         default:
 723                 matched_src = NULL;
 724                 error("src refspec %s matches more than one.", rs->src);
 725                 break;
 726         }
 727
 728         if (!matched_src)
 729                 errs = 1;
 730
 731         if (!dst_value) {
 732                 if (!matched_src)
 733                         return errs;
 734                 dst_value = matched_src->name;
 735         }
 736
 737         switch (count_refspec_match(dst_value, dst, &matched_dst)) {
 738         case 1:
 739                 break;
 740         case 0:
 741                 if (!memcmp(dst_value, "refs/", 5))
 742                         matched_dst = make_linked_ref(dst_value, dst_tail);
 743                 else
 744                         error("dst refspec %s does not match any "
 745                               "existing ref on the remote and does "
 746                               "not start with refs/.", dst_value);
 747                 break;
 748         default:
 749                 matched_dst = NULL;
 750                 error("dst refspec %s matches more than one.",
 751                       dst_value);
 752                 break;
 753         }
 754         if (errs || !matched_dst)
 755                 return 1;
 756         if (matched_dst->peer_ref) {
 757                 errs = 1;
 758                 error("dst ref %s receives from more than one src.",
 759                       matched_dst->name);
 760         }
 761         else {
 762                 matched_dst->peer_ref = matched_src;
 763                 matched_dst->force = rs->force;
 764         }
 765         return errs;
 766 }
 767
 768 static int match_explicit_refs(struct ref *src, struct ref *dst,
 769                                struct ref ***dst_tail, struct refspec *rs,
 770                                int rs_nr)
 771 {
 772         int i, errs;
 773         for (i = errs = 0; i < rs_nr; i++)
 774                 errs |= match_explicit(src, dst, dst_tail, &rs[i], errs);
 775         return -errs;
 776 }
 777
 778 static const struct refspec *check_pattern_match(const struct refspec *rs,
 779                                                  int rs_nr,
 780                                                  const struct ref *src)
 781 {
 782         int i;
 783         for (i = 0; i < rs_nr; i++) {
 784                 if (rs[i].pattern &&
 785                     !prefixcmp(src->name, rs[i].src) &&
 786                     src->name[strlen(rs[i].src)] == '/')
 787                         return rs + i;
 788         }
 789         return NULL;
 790 }
 791
 792 /*
 793  * Note. This is used only by "push"; refspec matching rules for
 794  * push and fetch are subtly different, so do not try to reuse it
 795  * without thinking.
 796  */
 797 int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 798                int nr_refspec, const char **refspec, int flags)
 799 {
 800         struct refspec *rs =
 801                 parse_push_refspec(nr_refspec, (const char **) refspec);
 802         int send_all = flags & MATCH_REFS_ALL;
 803         int send_mirror = flags & MATCH_REFS_MIRROR;
 804
 805         if (match_explicit_refs(src, dst, dst_tail, rs, nr_refspec))
 806                 return -1;
 807
 808         /* pick the remainder */
 809         for ( ; src; src = src->next) {
 810                 struct ref *dst_peer;
 811                 const struct refspec *pat = NULL;
 812                 char *dst_name;
 813                 if (src->peer_ref)
 814                         continue;
 815                 if (nr_refspec) {
 816                         pat = check_pattern_match(rs, nr_refspec, src);
 817                         if (!pat)
 818                                 continue;
 819                 }
 820                 else if (!send_mirror && prefixcmp(src->name, "refs/heads/"))
 821                         /*
 822                          * "matching refs"; traditionally we pushed everything
 823                          * including refs outside refs/heads/ hierarchy, but
 824                          * that does not make much sense these days.
 825                          */
 826                         continue;
 827
 828                 if (pat) {
 829                         const char *dst_side = pat->dst ? pat->dst : pat->src;
 830                         dst_name = xmalloc(strlen(dst_side) +
 831                                            strlen(src->name) -
 832                                            strlen(pat->src) + 2);
 833                         strcpy(dst_name, dst_side);
 834                         strcat(dst_name, src->name + strlen(pat->src));
 835                 } else
 836                         dst_name = xstrdup(src->name);
 837                 dst_peer = find_ref_by_name(dst, dst_name);
 838                 if (dst_peer && dst_peer->peer_ref)
 839                         /* We're already sending something to this ref. */
 840                         goto free_name;
 841
 842                 if (!dst_peer && !nr_refspec && !(send_all || send_mirror))
 843                         /*
 844                          * Remote doesn't have it, and we have no
 845                          * explicit pattern, and we don't have
 846                          * --all nor --mirror.
 847                          */
 848                         goto free_name;
 849                 if (!dst_peer) {
 850                         /* Create a new one and link it */
 851                         dst_peer = make_linked_ref(dst_name, dst_tail);
 852                         hashcpy(dst_peer->new_sha1, src->new_sha1);
 853                 }
 854                 dst_peer->peer_ref = src;
 855                 if (pat)
 856                         dst_peer->force = pat->force;
 857         free_name:
 858                 free(dst_name);
 859         }
 860         return 0;
 861 }
 862
 863 struct branch *branch_get(const char *name)
 864 {
 865         struct branch *ret;
 866
 867         read_config();
 868         if (!name || !*name || !strcmp(name, "HEAD"))
 869                 ret = current_branch;
 870         else
 871                 ret = make_branch(name, 0);
 872         if (ret && ret->remote_name) {
 873                 ret->remote = remote_get(ret->remote_name);
 874                 if (ret->merge_nr) {
 875                         int i;
 876                         ret->merge = xcalloc(sizeof(*ret->merge),
 877                                              ret->merge_nr);
 878                         for (i = 0; i < ret->merge_nr; i++) {
 879                                 ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
 880                                 ret->merge[i]->src = xstrdup(ret->merge_name[i]);
 881                                 remote_find_tracking(ret->remote,
 882                                                      ret->merge[i]);
 883                         }
 884                 }
 885         }
 886         return ret;
 887 }
 888
 889 int branch_has_merge_config(struct branch *branch)
 890 {
 891         return branch && !!branch->merge;
 892 }
 893
 894 int branch_merge_matches(struct branch *branch,
 895                                  int i,
 896                                  const char *refname)
 897 {
 898         if (!branch || i < 0 || i >= branch->merge_nr)
 899                 return 0;
 900         return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
 901 }
 902
 903 static struct ref *get_expanded_map(const struct ref *remote_refs,
 904                                     const struct refspec *refspec)
 905 {
 906         const struct ref *ref;
 907         struct ref *ret = NULL;
 908         struct ref **tail = &ret;
 909
 910         int remote_prefix_len = strlen(refspec->src);
 911         int local_prefix_len = strlen(refspec->dst);
 912
 913         for (ref = remote_refs; ref; ref = ref->next) {
 914                 if (strchr(ref->name, '^'))
 915                         continue; /* a dereference item */
 916                 if (!prefixcmp(ref->name, refspec->src)) {
 917                         const char *match;
 918                         struct ref *cpy = copy_ref(ref);
 919                         match = ref->name + remote_prefix_len;
 920
 921                         cpy->peer_ref = alloc_ref(local_prefix_len +
 922                                                   strlen(match) + 1);
 923                         sprintf(cpy->peer_ref->name, "%s%s",
 924                                 refspec->dst, match);
 925                         if (refspec->force)
 926                                 cpy->peer_ref->force = 1;
 927                         *tail = cpy;
 928                         tail = &cpy->next;
 929                 }
 930         }
 931
 932         return ret;
 933 }
 934
 935 static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
 936 {
 937         const struct ref *ref;
 938         for (ref = refs; ref; ref = ref->next) {
 939                 if (refname_match(name, ref->name, ref_fetch_rules))
 940                         return ref;
 941         }
 942         return NULL;
 943 }
 944
 945 struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
 946 {
 947         const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
 948
 949         if (!ref)
 950                 return NULL;
 951
 952         return copy_ref(ref);
 953 }
 954
 955 static struct ref *get_local_ref(const char *name)
 956 {
 957         struct ref *ret;
 958         if (!name)
 959                 return NULL;
 960
 961         if (!prefixcmp(name, "refs/")) {
 962                 ret = alloc_ref(strlen(name) + 1);
 963                 strcpy(ret->name, name);
 964                 return ret;
 965         }
 966
 967         if (!prefixcmp(name, "heads/") ||
 968             !prefixcmp(name, "tags/") ||
 969             !prefixcmp(name, "remotes/")) {
 970                 ret = alloc_ref(strlen(name) + 6);
 971                 sprintf(ret->name, "refs/%s", name);
 972                 return ret;
 973         }
 974
 975         ret = alloc_ref(strlen(name) + 12);
 976         sprintf(ret->name, "refs/heads/%s", name);
 977         return ret;
 978 }
 979
 980 int get_fetch_map(const struct ref *remote_refs,
 981                   const struct refspec *refspec,
 982                   struct ref ***tail,
 983                   int missing_ok)
 984 {
 985         struct ref *ref_map, **rmp;
 986
 987         if (refspec->pattern) {
 988                 ref_map = get_expanded_map(remote_refs, refspec);
 989         } else {
 990                 const char *name = refspec->src[0] ? refspec->src : "HEAD";
 991
 992                 ref_map = get_remote_ref(remote_refs, name);
 993                 if (!missing_ok && !ref_map)
 994                         die("Couldn't find remote ref %s", name);
 995                 if (ref_map) {
 996                         ref_map->peer_ref = get_local_ref(refspec->dst);
 997                         if (ref_map->peer_ref && refspec->force)
 998                                 ref_map->peer_ref->force = 1;
 999                 }
1000         }
1001
1002         for (rmp = &ref_map; *rmp; ) {
1003                 if ((*rmp)->peer_ref) {
1004                         int st = check_ref_format((*rmp)->peer_ref->name + 5);
1005                         if (st && st != CHECK_REF_FORMAT_ONELEVEL) {
1006                                 struct ref *ignore = *rmp;
1007                                 error("* Ignoring funny ref '%s' locally",
1008                                       (*rmp)->peer_ref->name);
1009                                 *rmp = (*rmp)->next;
1010                                 free(ignore->peer_ref);
1011                                 free(ignore);
1012                                 continue;
1013                         }
1014                 }
1015                 rmp = &((*rmp)->next);
1016         }
1017
1018         if (ref_map)
1019                 tail_link_ref(ref_map, tail);
1020
1021         return 0;
1022 }