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         struct strbuf 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
 201         /*
 202          * With "slash", e.g. "git fetch jgarzik/netdev-2.6" when
 203          * reading from $GIT_DIR/branches/jgarzik fetches "HEAD" from
 204          * the partial URL obtained from the branches file plus
 205          * "/netdev-2.6" and does not store it in any tracking ref.
 206          * #branch specifier in the file is ignored.
 207          *
 208          * Otherwise, the branches file would have URL and optionally
 209          * #branch specified.  The "master" (or specified) branch is
 210          * fetched and stored in the local branch of the same name.
 211          */
 212         strbuf_init(&branch, 0);
 213         frag = strchr(p, '#');
 214         if (frag) {
 215                 *(frag++) = '\0';
 216                 strbuf_addf(&branch, "refs/heads/%s", frag);
 217         } else
 218                 strbuf_addstr(&branch, "refs/heads/master");
 219         if (!slash) {
 220                 strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 221         } else {
 222                 strbuf_reset(&branch);
 223                 strbuf_addstr(&branch, "HEAD:");
 224         }
 225         add_url(remote, p);
 226         add_fetch_refspec(remote, strbuf_detach(&branch, 0));
 227         remote->fetch_tags = 1; /* always auto-follow */
 228 }
 229
 230 static int handle_config(const char *key, const char *value)
 231 {
 232         const char *name;
 233         const char *subkey;
 234         struct remote *remote;
 235         struct branch *branch;
 236         if (!prefixcmp(key, "branch.")) {
 237                 name = key + 7;
 238                 subkey = strrchr(name, '.');
 239                 if (!subkey)
 240                         return 0;
 241                 branch = make_branch(name, subkey - name);
 242                 if (!strcmp(subkey, ".remote")) {
 243                         if (!value)
 244                                 return config_error_nonbool(key);
 245                         branch->remote_name = xstrdup(value);
 246                         if (branch == current_branch)
 247                                 default_remote_name = branch->remote_name;
 248                 } else if (!strcmp(subkey, ".merge")) {
 249                         if (!value)
 250                                 return config_error_nonbool(key);
 251                         add_merge(branch, xstrdup(value));
 252                 }
 253                 return 0;
 254         }
 255         if (prefixcmp(key,  "remote."))
 256                 return 0;
 257         name = key + 7;
 258         subkey = strrchr(name, '.');
 259         if (!subkey)
 260                 return error("Config with no key for remote %s", name);
 261         if (*subkey == '/') {
 262                 warning("Config remote shorthand cannot begin with '/': %s", name);
 263                 return 0;
 264         }
 265         remote = make_remote(name, subkey - name);
 266         if (!value) {
 267                 /* if we ever have a boolean variable, e.g. "remote.*.disabled"
 268                  * [remote "frotz"]
 269                  *      disabled
 270                  * is a valid way to set it to true; we get NULL in value so
 271                  * we need to handle it here.
 272                  *
 273                  * if (!strcmp(subkey, ".disabled")) {
 274                  *      val = git_config_bool(key, value);
 275                  *      return 0;
 276                  * } else
 277                  *
 278                  */
 279                 return 0; /* ignore unknown booleans */
 280         }
 281         if (!strcmp(subkey, ".url")) {
 282                 add_url(remote, xstrdup(value));
 283         } else if (!strcmp(subkey, ".push")) {
 284                 add_push_refspec(remote, xstrdup(value));
 285         } else if (!strcmp(subkey, ".fetch")) {
 286                 add_fetch_refspec(remote, xstrdup(value));
 287         } else if (!strcmp(subkey, ".receivepack")) {
 288                 if (!remote->receivepack)
 289                         remote->receivepack = xstrdup(value);
 290                 else
 291                         error("more than one receivepack given, using the first");
 292         } else if (!strcmp(subkey, ".uploadpack")) {
 293                 if (!remote->uploadpack)
 294                         remote->uploadpack = xstrdup(value);
 295                 else
 296                         error("more than one uploadpack given, using the first");
 297         } else if (!strcmp(subkey, ".tagopt")) {
 298                 if (!strcmp(value, "--no-tags"))
 299                         remote->fetch_tags = -1;
 300         } else if (!strcmp(subkey, ".proxy")) {
 301                 remote->http_proxy = xstrdup(value);
 302         }
 303         return 0;
 304 }
 305
 306 static void read_config(void)
 307 {
 308         unsigned char sha1[20];
 309         const char *head_ref;
 310         int flag;
 311         if (default_remote_name) // did this already
 312                 return;
 313         default_remote_name = xstrdup("origin");
 314         current_branch = NULL;
 315         head_ref = resolve_ref("HEAD", sha1, 0, &flag);
 316         if (head_ref && (flag & REF_ISSYMREF) &&
 317             !prefixcmp(head_ref, "refs/heads/")) {
 318                 current_branch =
 319                         make_branch(head_ref + strlen("refs/heads/"), 0);
 320         }
 321         git_config(handle_config);
 322 }
 323
 324 static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch)
 325 {
 326         int i;
 327         int st;
 328         struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 329
 330         for (i = 0; i < nr_refspec; i++) {
 331                 size_t llen, rlen;
 332                 int is_glob;
 333                 const char *lhs, *rhs;
 334
 335                 llen = rlen = is_glob = 0;
 336
 337                 lhs = refspec[i];
 338                 if (*lhs == '+') {
 339                         rs[i].force = 1;
 340                         lhs++;
 341                 }
 342
 343                 rhs = strrchr(lhs, ':');
 344                 if (rhs) {
 345                         rhs++;
 346                         rlen = strlen(rhs);
 347                         is_glob = (2 <= rlen && !strcmp(rhs + rlen - 2, "/*"));
 348                         if (is_glob)
 349                                 rlen -= 2;
 350                         rs[i].dst = xstrndup(rhs, rlen);
 351                 }
 352
 353                 llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 354                 if (2 <= llen && !memcmp(lhs + llen - 2, "/*", 2)) {
 355                         if ((rhs && !is_glob) || (!rhs && fetch))
 356                                 goto invalid;
 357                         is_glob = 1;
 358                         llen -= 2;
 359                 } else if (rhs && is_glob) {
 360                         goto invalid;
 361                 }
 362
 363                 rs[i].pattern = is_glob;
 364                 rs[i].src = xstrndup(lhs, llen);
 365
 366                 if (fetch) {
 367                         /*
 368                          * LHS
 369                          * - empty is allowed; it means HEAD.
 370                          * - otherwise it must be a valid looking ref.
 371                          */
 372                         if (!*rs[i].src)
 373                                 ; /* empty is ok */
 374                         else {
 375                                 st = check_ref_format(rs[i].src);
 376                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 377                                         goto invalid;
 378                         }
 379                         /*
 380                          * RHS
 381                          * - missing is ok, and is same as empty.
 382                          * - empty is ok; it means not to store.
 383                          * - otherwise it must be a valid looking ref.
 384                          */
 385                         if (!rs[i].dst) {
 386                                 ; /* ok */
 387                         } else if (!*rs[i].dst) {
 388                                 ; /* ok */
 389                         } else {
 390                                 st = check_ref_format(rs[i].dst);
 391                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 392                                         goto invalid;
 393                         }
 394                 } else {
 395                         /*
 396                          * LHS
 397                          * - empty is allowed; it means delete.
 398                          * - when wildcarded, it must be a valid looking ref.
 399                          * - otherwise, it must be an extended SHA-1, but
 400                          *   there is no existing way to validate this.
 401                          */
 402                         if (!*rs[i].src)
 403                                 ; /* empty is ok */
 404                         else if (is_glob) {
 405                                 st = check_ref_format(rs[i].src);
 406                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 407                                         goto invalid;
 408                         }
 409                         else
 410                                 ; /* anything goes, for now */
 411                         /*
 412                          * RHS
 413                          * - missing is allowed, but LHS then must be a
 414                          *   valid looking ref.
 415                          * - empty is not allowed.
 416                          * - otherwise it must be a valid looking ref.
 417                          */
 418                         if (!rs[i].dst) {
 419                                 st = check_ref_format(rs[i].src);
 420                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 421                                         goto invalid;
 422                         } else if (!*rs[i].dst) {
 423                                 goto invalid;
 424                         } else {
 425                                 st = check_ref_format(rs[i].dst);
 426                                 if (st && st != CHECK_REF_FORMAT_ONELEVEL)
 427                                         goto invalid;
 428                         }
 429                 }
 430         }
 431         return rs;
 432
 433  invalid:
 434         die("Invalid refspec '%s'", refspec[i]);
 435 }
 436
 437 struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 438 {
 439         return parse_refspec_internal(nr_refspec, refspec, 1);
 440 }
 441
 442 struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 443 {
 444         return parse_refspec_internal(nr_refspec, refspec, 0);
 445 }
 446
 447 static int valid_remote_nick(const char *name)
 448 {
 449         if (!name[0] || /* not empty */
 450             (name[0] == '.' && /* not "." */
 451              (!name[1] || /* not ".." */
 452               (name[1] == '.' && !name[2]))))
 453                 return 0;
 454         return !strchr(name, '/'); /* no slash */
 455 }
 456
 457 struct remote *remote_get(const char *name)
 458 {
 459         struct remote *ret;
 460
 461         read_config();
 462         if (!name)
 463                 name = default_remote_name;
 464         ret = make_remote(name, 0);
 465         if (valid_remote_nick(name)) {
 466                 if (!ret->url)
 467                         read_remotes_file(ret);
 468                 if (!ret->url)
 469                         read_branches_file(ret);
 470         }
 471         if (!ret->url)
 472                 add_url(ret, name);
 473         if (!ret->url)
 474                 return NULL;
 475         ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 476         ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 477         return ret;
 478 }
 479
 480 int for_each_remote(each_remote_fn fn, void *priv)
 481 {
 482         int i, result = 0;
 483         read_config();
 484         for (i = 0; i < allocated_remotes && !result; i++) {
 485                 struct remote *r = remotes[i];
 486                 if (!r)
 487                         continue;
 488                 if (!r->fetch)
 489                         r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 490                                                        r->fetch_refspec);
 491                 if (!r->push)
 492                         r->push = parse_push_refspec(r->push_refspec_nr,
 493                                                      r->push_refspec);
 494                 result = fn(r, priv);
 495         }
 496         return result;
 497 }
 498
 499 void ref_remove_duplicates(struct ref *ref_map)
 500 {
 501         struct ref **posn;
 502         struct ref *next;
 503         for (; ref_map; ref_map = ref_map->next) {
 504                 if (!ref_map->peer_ref)
 505                         continue;
 506                 posn = &ref_map->next;
 507                 while (*posn) {
 508                         if ((*posn)->peer_ref &&
 509                             !strcmp((*posn)->peer_ref->name,
 510                                     ref_map->peer_ref->name)) {
 511                                 if (strcmp((*posn)->name, ref_map->name))
 512                                         die("%s tracks both %s and %s",
 513                                             ref_map->peer_ref->name,
 514                                             (*posn)->name, ref_map->name);
 515                                 next = (*posn)->next;
 516                                 free((*posn)->peer_ref);
 517                                 free(*posn);
 518                                 *posn = next;
 519                         } else {
 520                                 posn = &(*posn)->next;
 521                         }
 522                 }
 523         }
 524 }
 525
 526 int remote_has_url(struct remote *remote, const char *url)
 527 {
 528         int i;
 529         for (i = 0; i < remote->url_nr; i++) {
 530                 if (!strcmp(remote->url[i], url))
 531                         return 1;
 532         }
 533         return 0;
 534 }
 535
 536 int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 537 {
 538         int find_src = refspec->src == NULL;
 539         char *needle, **result;
 540         int i;
 541
 542         if (find_src) {
 543                 if (!refspec->dst)
 544                         return error("find_tracking: need either src or dst");
 545                 needle = refspec->dst;
 546                 result = &refspec->src;
 547         } else {
 548                 needle = refspec->src;
 549                 result = &refspec->dst;
 550         }
 551
 552         for (i = 0; i < remote->fetch_refspec_nr; i++) {
 553                 struct refspec *fetch = &remote->fetch[i];
 554                 const char *key = find_src ? fetch->dst : fetch->src;
 555                 const char *value = find_src ? fetch->src : fetch->dst;
 556                 if (!fetch->dst)
 557                         continue;
 558                 if (fetch->pattern) {
 559                         if (!prefixcmp(needle, key) &&
 560                             needle[strlen(key)] == '/') {
 561                                 *result = xmalloc(strlen(value) +
 562                                                   strlen(needle) -
 563                                                   strlen(key) + 1);
 564                                 strcpy(*result, value);
 565                                 strcpy(*result + strlen(value),
 566                                        needle + strlen(key));
 567                                 refspec->force = fetch->force;
 568                                 return 0;
 569                         }
 570                 } else if (!strcmp(needle, key)) {
 571                         *result = xstrdup(value);
 572                         refspec->force = fetch->force;
 573                         return 0;
 574                 }
 575         }
 576         return -1;
 577 }
 578
 579 struct ref *alloc_ref(unsigned namelen)
 580 {
 581         struct ref *ret = xmalloc(sizeof(struct ref) + namelen);
 582         memset(ret, 0, sizeof(struct ref) + namelen);
 583         return ret;
 584 }
 585
 586 static struct ref *copy_ref(const struct ref *ref)
 587 {
 588         struct ref *ret = xmalloc(sizeof(struct ref) + strlen(ref->name) + 1);
 589         memcpy(ret, ref, sizeof(struct ref) + strlen(ref->name) + 1);
 590         ret->next = NULL;
 591         return ret;
 592 }
 593
 594 struct ref *copy_ref_list(const struct ref *ref)
 595 {
 596         struct ref *ret = NULL;
 597         struct ref **tail = &ret;
 598         while (ref) {
 599                 *tail = copy_ref(ref);
 600                 ref = ref->next;
 601                 tail = &((*tail)->next);
 602         }
 603         return ret;
 604 }
 605
 606 void free_refs(struct ref *ref)
 607 {
 608         struct ref *next;
 609         while (ref) {
 610                 next = ref->next;
 611                 if (ref->peer_ref)
 612                         free(ref->peer_ref);
 613                 free(ref);
 614                 ref = next;
 615         }
 616 }
 617
 618 static int count_refspec_match(const char *pattern,
 619                                struct ref *refs,
 620                                struct ref **matched_ref)
 621 {
 622         int patlen = strlen(pattern);
 623         struct ref *matched_weak = NULL;
 624         struct ref *matched = NULL;
 625         int weak_match = 0;
 626         int match = 0;
 627
 628         for (weak_match = match = 0; refs; refs = refs->next) {
 629                 char *name = refs->name;
 630                 int namelen = strlen(name);
 631
 632                 if (!refname_match(pattern, name, ref_rev_parse_rules))
 633                         continue;
 634
 635                 /* A match is "weak" if it is with refs outside
 636                  * heads or tags, and did not specify the pattern
 637                  * in full (e.g. "refs/remotes/origin/master") or at
 638                  * least from the toplevel (e.g. "remotes/origin/master");
 639                  * otherwise "git push $URL master" would result in
 640                  * ambiguity between remotes/origin/master and heads/master
 641                  * at the remote site.
 642                  */
 643                 if (namelen != patlen &&
 644                     patlen != namelen - 5 &&
 645                     prefixcmp(name, "refs/heads/") &&
 646                     prefixcmp(name, "refs/tags/")) {
 647                         /* We want to catch the case where only weak
 648                          * matches are found and there are multiple
 649                          * matches, and where more than one strong
 650                          * matches are found, as ambiguous.  One
 651                          * strong match with zero or more weak matches
 652                          * are acceptable as a unique match.
 653                          */
 654                         matched_weak = refs;
 655                         weak_match++;
 656                 }
 657                 else {
 658                         matched = refs;
 659                         match++;
 660                 }
 661         }
 662         if (!matched) {
 663                 *matched_ref = matched_weak;
 664                 return weak_match;
 665         }
 666         else {
 667                 *matched_ref = matched;
 668                 return match;
 669         }
 670 }
 671
 672 static void tail_link_ref(struct ref *ref, struct ref ***tail)
 673 {
 674         **tail = ref;
 675         while (ref->next)
 676                 ref = ref->next;
 677         *tail = &ref->next;
 678 }
 679
 680 static struct ref *try_explicit_object_name(const char *name)
 681 {
 682         unsigned char sha1[20];
 683         struct ref *ref;
 684         int len;
 685
 686         if (!*name) {
 687                 ref = alloc_ref(20);
 688                 strcpy(ref->name, "(delete)");
 689                 hashclr(ref->new_sha1);
 690                 return ref;
 691         }
 692         if (get_sha1(name, sha1))
 693                 return NULL;
 694         len = strlen(name) + 1;
 695         ref = alloc_ref(len);
 696         memcpy(ref->name, name, len);
 697         hashcpy(ref->new_sha1, sha1);
 698         return ref;
 699 }
 700
 701 static struct ref *make_linked_ref(const char *name, struct ref ***tail)
 702 {
 703         struct ref *ret;
 704         size_t len;
 705
 706         len = strlen(name) + 1;
 707         ret = alloc_ref(len);
 708         memcpy(ret->name, name, len);
 709         tail_link_ref(ret, tail);
 710         return ret;
 711 }
 712
 713 static int match_explicit(struct ref *src, struct ref *dst,
 714                           struct ref ***dst_tail,
 715                           struct refspec *rs,
 716                           int errs)
 717 {
 718         struct ref *matched_src, *matched_dst;
 719
 720         const char *dst_value = rs->dst;
 721
 722         if (rs->pattern)
 723                 return errs;
 724
 725         matched_src = matched_dst = NULL;
 726         switch (count_refspec_match(rs->src, src, &matched_src)) {
 727         case 1:
 728                 break;
 729         case 0:
 730                 /* The source could be in the get_sha1() format
 731                  * not a reference name.  :refs/other is a
 732                  * way to delete 'other' ref at the remote end.
 733                  */
 734                 matched_src = try_explicit_object_name(rs->src);
 735                 if (!matched_src)
 736                         error("src refspec %s does not match any.", rs->src);
 737                 break;
 738         default:
 739                 matched_src = NULL;
 740                 error("src refspec %s matches more than one.", rs->src);
 741                 break;
 742         }
 743
 744         if (!matched_src)
 745                 errs = 1;
 746
 747         if (!dst_value) {
 748                 if (!matched_src)
 749                         return errs;
 750                 dst_value = matched_src->name;
 751         }
 752
 753         switch (count_refspec_match(dst_value, dst, &matched_dst)) {
 754         case 1:
 755                 break;
 756         case 0:
 757                 if (!memcmp(dst_value, "refs/", 5))
 758                         matched_dst = make_linked_ref(dst_value, dst_tail);
 759                 else
 760                         error("dst refspec %s does not match any "
 761                               "existing ref on the remote and does "
 762                               "not start with refs/.", dst_value);
 763                 break;
 764         default:
 765                 matched_dst = NULL;
 766                 error("dst refspec %s matches more than one.",
 767                       dst_value);
 768                 break;
 769         }
 770         if (errs || !matched_dst)
 771                 return 1;
 772         if (matched_dst->peer_ref) {
 773                 errs = 1;
 774                 error("dst ref %s receives from more than one src.",
 775                       matched_dst->name);
 776         }
 777         else {
 778                 matched_dst->peer_ref = matched_src;
 779                 matched_dst->force = rs->force;
 780         }
 781         return errs;
 782 }
 783
 784 static int match_explicit_refs(struct ref *src, struct ref *dst,
 785                                struct ref ***dst_tail, struct refspec *rs,
 786                                int rs_nr)
 787 {
 788         int i, errs;
 789         for (i = errs = 0; i < rs_nr; i++)
 790                 errs |= match_explicit(src, dst, dst_tail, &rs[i], errs);
 791         return -errs;
 792 }
 793
 794 static const struct refspec *check_pattern_match(const struct refspec *rs,
 795                                                  int rs_nr,
 796                                                  const struct ref *src)
 797 {
 798         int i;
 799         for (i = 0; i < rs_nr; i++) {
 800                 if (rs[i].pattern &&
 801                     !prefixcmp(src->name, rs[i].src) &&
 802                     src->name[strlen(rs[i].src)] == '/')
 803                         return rs + i;
 804         }
 805         return NULL;
 806 }
 807
 808 /*
 809  * Note. This is used only by "push"; refspec matching rules for
 810  * push and fetch are subtly different, so do not try to reuse it
 811  * without thinking.
 812  */
 813 int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 814                int nr_refspec, const char **refspec, int flags)
 815 {
 816         struct refspec *rs =
 817                 parse_push_refspec(nr_refspec, (const char **) refspec);
 818         int send_all = flags & MATCH_REFS_ALL;
 819         int send_mirror = flags & MATCH_REFS_MIRROR;
 820
 821         if (match_explicit_refs(src, dst, dst_tail, rs, nr_refspec))
 822                 return -1;
 823
 824         /* pick the remainder */
 825         for ( ; src; src = src->next) {
 826                 struct ref *dst_peer;
 827                 const struct refspec *pat = NULL;
 828                 char *dst_name;
 829                 if (src->peer_ref)
 830                         continue;
 831                 if (nr_refspec) {
 832                         pat = check_pattern_match(rs, nr_refspec, src);
 833                         if (!pat)
 834                                 continue;
 835                 }
 836                 else if (!send_mirror && prefixcmp(src->name, "refs/heads/"))
 837                         /*
 838                          * "matching refs"; traditionally we pushed everything
 839                          * including refs outside refs/heads/ hierarchy, but
 840                          * that does not make much sense these days.
 841                          */
 842                         continue;
 843
 844                 if (pat) {
 845                         const char *dst_side = pat->dst ? pat->dst : pat->src;
 846                         dst_name = xmalloc(strlen(dst_side) +
 847                                            strlen(src->name) -
 848                                            strlen(pat->src) + 2);
 849                         strcpy(dst_name, dst_side);
 850                         strcat(dst_name, src->name + strlen(pat->src));
 851                 } else
 852                         dst_name = xstrdup(src->name);
 853                 dst_peer = find_ref_by_name(dst, dst_name);
 854                 if (dst_peer && dst_peer->peer_ref)
 855                         /* We're already sending something to this ref. */
 856                         goto free_name;
 857
 858                 if (!dst_peer && !nr_refspec && !(send_all || send_mirror))
 859                         /*
 860                          * Remote doesn't have it, and we have no
 861                          * explicit pattern, and we don't have
 862                          * --all nor --mirror.
 863                          */
 864                         goto free_name;
 865                 if (!dst_peer) {
 866                         /* Create a new one and link it */
 867                         dst_peer = make_linked_ref(dst_name, dst_tail);
 868                         hashcpy(dst_peer->new_sha1, src->new_sha1);
 869                 }
 870                 dst_peer->peer_ref = src;
 871                 if (pat)
 872                         dst_peer->force = pat->force;
 873         free_name:
 874                 free(dst_name);
 875         }
 876         return 0;
 877 }
 878
 879 struct branch *branch_get(const char *name)
 880 {
 881         struct branch *ret;
 882
 883         read_config();
 884         if (!name || !*name || !strcmp(name, "HEAD"))
 885                 ret = current_branch;
 886         else
 887                 ret = make_branch(name, 0);
 888         if (ret && ret->remote_name) {
 889                 ret->remote = remote_get(ret->remote_name);
 890                 if (ret->merge_nr) {
 891                         int i;
 892                         ret->merge = xcalloc(sizeof(*ret->merge),
 893                                              ret->merge_nr);
 894                         for (i = 0; i < ret->merge_nr; i++) {
 895                                 ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
 896                                 ret->merge[i]->src = xstrdup(ret->merge_name[i]);
 897                                 remote_find_tracking(ret->remote,
 898                                                      ret->merge[i]);
 899                         }
 900                 }
 901         }
 902         return ret;
 903 }
 904
 905 int branch_has_merge_config(struct branch *branch)
 906 {
 907         return branch && !!branch->merge;
 908 }
 909
 910 int branch_merge_matches(struct branch *branch,
 911                                  int i,
 912                                  const char *refname)
 913 {
 914         if (!branch || i < 0 || i >= branch->merge_nr)
 915                 return 0;
 916         return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
 917 }
 918
 919 static struct ref *get_expanded_map(const struct ref *remote_refs,
 920                                     const struct refspec *refspec)
 921 {
 922         const struct ref *ref;
 923         struct ref *ret = NULL;
 924         struct ref **tail = &ret;
 925
 926         int remote_prefix_len = strlen(refspec->src);
 927         int local_prefix_len = strlen(refspec->dst);
 928
 929         for (ref = remote_refs; ref; ref = ref->next) {
 930                 if (strchr(ref->name, '^'))
 931                         continue; /* a dereference item */
 932                 if (!prefixcmp(ref->name, refspec->src)) {
 933                         const char *match;
 934                         struct ref *cpy = copy_ref(ref);
 935                         match = ref->name + remote_prefix_len;
 936
 937                         cpy->peer_ref = alloc_ref(local_prefix_len +
 938                                                   strlen(match) + 1);
 939                         sprintf(cpy->peer_ref->name, "%s%s",
 940                                 refspec->dst, match);
 941                         if (refspec->force)
 942                                 cpy->peer_ref->force = 1;
 943                         *tail = cpy;
 944                         tail = &cpy->next;
 945                 }
 946         }
 947
 948         return ret;
 949 }
 950
 951 static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
 952 {
 953         const struct ref *ref;
 954         for (ref = refs; ref; ref = ref->next) {
 955                 if (refname_match(name, ref->name, ref_fetch_rules))
 956                         return ref;
 957         }
 958         return NULL;
 959 }
 960
 961 struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
 962 {
 963         const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
 964
 965         if (!ref)
 966                 return NULL;
 967
 968         return copy_ref(ref);
 969 }
 970
 971 static struct ref *get_local_ref(const char *name)
 972 {
 973         struct ref *ret;
 974         if (!name)
 975                 return NULL;
 976
 977         if (!prefixcmp(name, "refs/")) {
 978                 ret = alloc_ref(strlen(name) + 1);
 979                 strcpy(ret->name, name);
 980                 return ret;
 981         }
 982
 983         if (!prefixcmp(name, "heads/") ||
 984             !prefixcmp(name, "tags/") ||
 985             !prefixcmp(name, "remotes/")) {
 986                 ret = alloc_ref(strlen(name) + 6);
 987                 sprintf(ret->name, "refs/%s", name);
 988                 return ret;
 989         }
 990
 991         ret = alloc_ref(strlen(name) + 12);
 992         sprintf(ret->name, "refs/heads/%s", name);
 993         return ret;
 994 }
 995
 996 int get_fetch_map(const struct ref *remote_refs,
 997                   const struct refspec *refspec,
 998                   struct ref ***tail,
 999                   int missing_ok)
1000 {
1001         struct ref *ref_map, **rmp;
1002
1003         if (refspec->pattern) {
1004                 ref_map = get_expanded_map(remote_refs, refspec);
1005         } else {
1006                 const char *name = refspec->src[0] ? refspec->src : "HEAD";
1007
1008                 ref_map = get_remote_ref(remote_refs, name);
1009                 if (!missing_ok && !ref_map)
1010                         die("Couldn't find remote ref %s", name);
1011                 if (ref_map) {
1012                         ref_map->peer_ref = get_local_ref(refspec->dst);
1013                         if (ref_map->peer_ref && refspec->force)
1014                                 ref_map->peer_ref->force = 1;
1015                 }
1016         }
1017
1018         for (rmp = &ref_map; *rmp; ) {
1019                 if ((*rmp)->peer_ref) {
1020                         int st = check_ref_format((*rmp)->peer_ref->name + 5);
1021                         if (st && st != CHECK_REF_FORMAT_ONELEVEL) {
1022                                 struct ref *ignore = *rmp;
1023                                 error("* Ignoring funny ref '%s' locally",
1024                                       (*rmp)->peer_ref->name);
1025                                 *rmp = (*rmp)->next;
1026                                 free(ignore->peer_ref);
1027                                 free(ignore);
1028                                 continue;
1029                         }
1030                 }
1031                 rmp = &((*rmp)->next);
1032         }
1033
1034         if (ref_map)
1035                 tail_link_ref(ref_map, tail);
1036
1037         return 0;
1038 }