git.oblomov.eu Git - git/blob - remote.c

   1 #include "cache.h"
   2 #include "remote.h"
   3 #include "refs.h"
   4 #include "commit.h"
   5 #include "diff.h"
   6 #include "revision.h"
   7 #include "dir.h"
   8 #include "tag.h"
   9 #include "string-list.h"
  10 #include "mergesort.h"
  11
  12 enum map_direction { FROM_SRC, FROM_DST };
  13
  14 static struct refspec s_tag_refspec = {
  15         0,
  16         1,
  17         0,
  18         0,
  19         "refs/tags/*",
  20         "refs/tags/*"
  21 };
  22
  23 const struct refspec *tag_refspec = &s_tag_refspec;
  24
  25 struct counted_string {
  26         size_t len;
  27         const char *s;
  28 };
  29 struct rewrite {
  30         const char *base;
  31         size_t baselen;
  32         struct counted_string *instead_of;
  33         int instead_of_nr;
  34         int instead_of_alloc;
  35 };
  36 struct rewrites {
  37         struct rewrite **rewrite;
  38         int rewrite_alloc;
  39         int rewrite_nr;
  40 };
  41
  42 static struct remote **remotes;
  43 static int remotes_alloc;
  44 static int remotes_nr;
  45
  46 static struct branch **branches;
  47 static int branches_alloc;
  48 static int branches_nr;
  49
  50 static struct branch *current_branch;
  51 static const char *default_remote_name;
  52 static const char *branch_pushremote_name;
  53 static const char *pushremote_name;
  54 static int explicit_default_remote_name;
  55
  56 static struct rewrites rewrites;
  57 static struct rewrites rewrites_push;
  58
  59 #define BUF_SIZE (2048)
  60 static char buffer[BUF_SIZE];
  61
  62 static int valid_remote(const struct remote *remote)
  63 {
  64         return (!!remote->url) || (!!remote->foreign_vcs);
  65 }
  66
  67 static const char *alias_url(const char *url, struct rewrites *r)
  68 {
  69         int i, j;
  70         char *ret;
  71         struct counted_string *longest;
  72         int longest_i;
  73
  74         longest = NULL;
  75         longest_i = -1;
  76         for (i = 0; i < r->rewrite_nr; i++) {
  77                 if (!r->rewrite[i])
  78                         continue;
  79                 for (j = 0; j < r->rewrite[i]->instead_of_nr; j++) {
  80                         if (!prefixcmp(url, r->rewrite[i]->instead_of[j].s) &&
  81                             (!longest ||
  82                              longest->len < r->rewrite[i]->instead_of[j].len)) {
  83                                 longest = &(r->rewrite[i]->instead_of[j]);
  84                                 longest_i = i;
  85                         }
  86                 }
  87         }
  88         if (!longest)
  89                 return url;
  90
  91         ret = xmalloc(r->rewrite[longest_i]->baselen +
  92                      (strlen(url) - longest->len) + 1);
  93         strcpy(ret, r->rewrite[longest_i]->base);
  94         strcpy(ret + r->rewrite[longest_i]->baselen, url + longest->len);
  95         return ret;
  96 }
  97
  98 static void add_push_refspec(struct remote *remote, const char *ref)
  99 {
 100         ALLOC_GROW(remote->push_refspec,
 101                    remote->push_refspec_nr + 1,
 102                    remote->push_refspec_alloc);
 103         remote->push_refspec[remote->push_refspec_nr++] = ref;
 104 }
 105
 106 static void add_fetch_refspec(struct remote *remote, const char *ref)
 107 {
 108         ALLOC_GROW(remote->fetch_refspec,
 109                    remote->fetch_refspec_nr + 1,
 110                    remote->fetch_refspec_alloc);
 111         remote->fetch_refspec[remote->fetch_refspec_nr++] = ref;
 112 }
 113
 114 static void add_url(struct remote *remote, const char *url)
 115 {
 116         ALLOC_GROW(remote->url, remote->url_nr + 1, remote->url_alloc);
 117         remote->url[remote->url_nr++] = url;
 118 }
 119
 120 static void add_pushurl(struct remote *remote, const char *pushurl)
 121 {
 122         ALLOC_GROW(remote->pushurl, remote->pushurl_nr + 1, remote->pushurl_alloc);
 123         remote->pushurl[remote->pushurl_nr++] = pushurl;
 124 }
 125
 126 static void add_pushurl_alias(struct remote *remote, const char *url)
 127 {
 128         const char *pushurl = alias_url(url, &rewrites_push);
 129         if (pushurl != url)
 130                 add_pushurl(remote, pushurl);
 131 }
 132
 133 static void add_url_alias(struct remote *remote, const char *url)
 134 {
 135         add_url(remote, alias_url(url, &rewrites));
 136         add_pushurl_alias(remote, url);
 137 }
 138
 139 static struct remote *make_remote(const char *name, int len)
 140 {
 141         struct remote *ret;
 142         int i;
 143
 144         for (i = 0; i < remotes_nr; i++) {
 145                 if (len ? (!strncmp(name, remotes[i]->name, len) &&
 146                            !remotes[i]->name[len]) :
 147                     !strcmp(name, remotes[i]->name))
 148                         return remotes[i];
 149         }
 150
 151         ret = xcalloc(1, sizeof(struct remote));
 152         ret->prune = -1;  /* unspecified */
 153         ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 154         remotes[remotes_nr++] = ret;
 155         if (len)
 156                 ret->name = xstrndup(name, len);
 157         else
 158                 ret->name = xstrdup(name);
 159         return ret;
 160 }
 161
 162 static void add_merge(struct branch *branch, const char *name)
 163 {
 164         ALLOC_GROW(branch->merge_name, branch->merge_nr + 1,
 165                    branch->merge_alloc);
 166         branch->merge_name[branch->merge_nr++] = name;
 167 }
 168
 169 static struct branch *make_branch(const char *name, int len)
 170 {
 171         struct branch *ret;
 172         int i;
 173         char *refname;
 174
 175         for (i = 0; i < branches_nr; i++) {
 176                 if (len ? (!strncmp(name, branches[i]->name, len) &&
 177                            !branches[i]->name[len]) :
 178                     !strcmp(name, branches[i]->name))
 179                         return branches[i];
 180         }
 181
 182         ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 183         ret = xcalloc(1, sizeof(struct branch));
 184         branches[branches_nr++] = ret;
 185         if (len)
 186                 ret->name = xstrndup(name, len);
 187         else
 188                 ret->name = xstrdup(name);
 189         refname = xmalloc(strlen(name) + strlen("refs/heads/") + 1);
 190         strcpy(refname, "refs/heads/");
 191         strcpy(refname + strlen("refs/heads/"), ret->name);
 192         ret->refname = refname;
 193
 194         return ret;
 195 }
 196
 197 static struct rewrite *make_rewrite(struct rewrites *r, const char *base, int len)
 198 {
 199         struct rewrite *ret;
 200         int i;
 201
 202         for (i = 0; i < r->rewrite_nr; i++) {
 203                 if (len
 204                     ? (len == r->rewrite[i]->baselen &&
 205                        !strncmp(base, r->rewrite[i]->base, len))
 206                     : !strcmp(base, r->rewrite[i]->base))
 207                         return r->rewrite[i];
 208         }
 209
 210         ALLOC_GROW(r->rewrite, r->rewrite_nr + 1, r->rewrite_alloc);
 211         ret = xcalloc(1, sizeof(struct rewrite));
 212         r->rewrite[r->rewrite_nr++] = ret;
 213         if (len) {
 214                 ret->base = xstrndup(base, len);
 215                 ret->baselen = len;
 216         }
 217         else {
 218                 ret->base = xstrdup(base);
 219                 ret->baselen = strlen(base);
 220         }
 221         return ret;
 222 }
 223
 224 static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 225 {
 226         ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 227         rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 228         rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 229         rewrite->instead_of_nr++;
 230 }
 231
 232 static void read_remotes_file(struct remote *remote)
 233 {
 234         FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
 235
 236         if (!f)
 237                 return;
 238         remote->origin = REMOTE_REMOTES;
 239         while (fgets(buffer, BUF_SIZE, f)) {
 240                 int value_list;
 241                 char *s, *p;
 242
 243                 if (!prefixcmp(buffer, "URL:")) {
 244                         value_list = 0;
 245                         s = buffer + 4;
 246                 } else if (!prefixcmp(buffer, "Push:")) {
 247                         value_list = 1;
 248                         s = buffer + 5;
 249                 } else if (!prefixcmp(buffer, "Pull:")) {
 250                         value_list = 2;
 251                         s = buffer + 5;
 252                 } else
 253                         continue;
 254
 255                 while (isspace(*s))
 256                         s++;
 257                 if (!*s)
 258                         continue;
 259
 260                 p = s + strlen(s);
 261                 while (isspace(p[-1]))
 262                         *--p = 0;
 263
 264                 switch (value_list) {
 265                 case 0:
 266                         add_url_alias(remote, xstrdup(s));
 267                         break;
 268                 case 1:
 269                         add_push_refspec(remote, xstrdup(s));
 270                         break;
 271                 case 2:
 272                         add_fetch_refspec(remote, xstrdup(s));
 273                         break;
 274                 }
 275         }
 276         fclose(f);
 277 }
 278
 279 static void read_branches_file(struct remote *remote)
 280 {
 281         char *frag;
 282         struct strbuf branch = STRBUF_INIT;
 283         int n = 1000;
 284         FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 285         char *s, *p;
 286         int len;
 287
 288         if (!f)
 289                 return;
 290         s = fgets(buffer, BUF_SIZE, f);
 291         fclose(f);
 292         if (!s)
 293                 return;
 294         while (isspace(*s))
 295                 s++;
 296         if (!*s)
 297                 return;
 298         remote->origin = REMOTE_BRANCHES;
 299         p = s + strlen(s);
 300         while (isspace(p[-1]))
 301                 *--p = 0;
 302         len = p - s;
 303         p = xmalloc(len + 1);
 304         strcpy(p, s);
 305
 306         /*
 307          * The branches file would have URL and optionally
 308          * #branch specified.  The "master" (or specified) branch is
 309          * fetched and stored in the local branch of the same name.
 310          */
 311         frag = strchr(p, '#');
 312         if (frag) {
 313                 *(frag++) = '\0';
 314                 strbuf_addf(&branch, "refs/heads/%s", frag);
 315         } else
 316                 strbuf_addstr(&branch, "refs/heads/master");
 317
 318         strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 319         add_url_alias(remote, p);
 320         add_fetch_refspec(remote, strbuf_detach(&branch, NULL));
 321         /*
 322          * Cogito compatible push: push current HEAD to remote #branch
 323          * (master if missing)
 324          */
 325         strbuf_init(&branch, 0);
 326         strbuf_addstr(&branch, "HEAD");
 327         if (frag)
 328                 strbuf_addf(&branch, ":refs/heads/%s", frag);
 329         else
 330                 strbuf_addstr(&branch, ":refs/heads/master");
 331         add_push_refspec(remote, strbuf_detach(&branch, NULL));
 332         remote->fetch_tags = 1; /* always auto-follow */
 333 }
 334
 335 static int handle_config(const char *key, const char *value, void *cb)
 336 {
 337         const char *name;
 338         const char *subkey;
 339         struct remote *remote;
 340         struct branch *branch;
 341         if (!prefixcmp(key, "branch.")) {
 342                 name = key + 7;
 343                 subkey = strrchr(name, '.');
 344                 if (!subkey)
 345                         return 0;
 346                 branch = make_branch(name, subkey - name);
 347                 if (!strcmp(subkey, ".remote")) {
 348                         if (git_config_string(&branch->remote_name, key, value))
 349                                 return -1;
 350                         if (branch == current_branch) {
 351                                 default_remote_name = branch->remote_name;
 352                                 explicit_default_remote_name = 1;
 353                         }
 354                 } else if (!strcmp(subkey, ".pushremote")) {
 355                         if (branch == current_branch)
 356                                 if (git_config_string(&branch_pushremote_name, key, value))
 357                                         return -1;
 358                 } else if (!strcmp(subkey, ".merge")) {
 359                         if (!value)
 360                                 return config_error_nonbool(key);
 361                         add_merge(branch, xstrdup(value));
 362                 }
 363                 return 0;
 364         }
 365         if (!prefixcmp(key, "url.")) {
 366                 struct rewrite *rewrite;
 367                 name = key + 4;
 368                 subkey = strrchr(name, '.');
 369                 if (!subkey)
 370                         return 0;
 371                 if (!strcmp(subkey, ".insteadof")) {
 372                         rewrite = make_rewrite(&rewrites, name, subkey - name);
 373                         if (!value)
 374                                 return config_error_nonbool(key);
 375                         add_instead_of(rewrite, xstrdup(value));
 376                 } else if (!strcmp(subkey, ".pushinsteadof")) {
 377                         rewrite = make_rewrite(&rewrites_push, name, subkey - name);
 378                         if (!value)
 379                                 return config_error_nonbool(key);
 380                         add_instead_of(rewrite, xstrdup(value));
 381                 }
 382         }
 383
 384         if (prefixcmp(key,  "remote."))
 385                 return 0;
 386         name = key + 7;
 387
 388         /* Handle remote.* variables */
 389         if (!strcmp(name, "pushdefault"))
 390                 return git_config_string(&pushremote_name, key, value);
 391
 392         /* Handle remote.<name>.* variables */
 393         if (*name == '/') {
 394                 warning("Config remote shorthand cannot begin with '/': %s",
 395                         name);
 396                 return 0;
 397         }
 398         subkey = strrchr(name, '.');
 399         if (!subkey)
 400                 return 0;
 401         remote = make_remote(name, subkey - name);
 402         remote->origin = REMOTE_CONFIG;
 403         if (!strcmp(subkey, ".mirror"))
 404                 remote->mirror = git_config_bool(key, value);
 405         else if (!strcmp(subkey, ".skipdefaultupdate"))
 406                 remote->skip_default_update = git_config_bool(key, value);
 407         else if (!strcmp(subkey, ".skipfetchall"))
 408                 remote->skip_default_update = git_config_bool(key, value);
 409         else if (!strcmp(subkey, ".prune"))
 410                 remote->prune = git_config_bool(key, value);
 411         else if (!strcmp(subkey, ".url")) {
 412                 const char *v;
 413                 if (git_config_string(&v, key, value))
 414                         return -1;
 415                 add_url(remote, v);
 416         } else if (!strcmp(subkey, ".pushurl")) {
 417                 const char *v;
 418                 if (git_config_string(&v, key, value))
 419                         return -1;
 420                 add_pushurl(remote, v);
 421         } else if (!strcmp(subkey, ".push")) {
 422                 const char *v;
 423                 if (git_config_string(&v, key, value))
 424                         return -1;
 425                 add_push_refspec(remote, v);
 426         } else if (!strcmp(subkey, ".fetch")) {
 427                 const char *v;
 428                 if (git_config_string(&v, key, value))
 429                         return -1;
 430                 add_fetch_refspec(remote, v);
 431         } else if (!strcmp(subkey, ".receivepack")) {
 432                 const char *v;
 433                 if (git_config_string(&v, key, value))
 434                         return -1;
 435                 if (!remote->receivepack)
 436                         remote->receivepack = v;
 437                 else
 438                         error("more than one receivepack given, using the first");
 439         } else if (!strcmp(subkey, ".uploadpack")) {
 440                 const char *v;
 441                 if (git_config_string(&v, key, value))
 442                         return -1;
 443                 if (!remote->uploadpack)
 444                         remote->uploadpack = v;
 445                 else
 446                         error("more than one uploadpack given, using the first");
 447         } else if (!strcmp(subkey, ".tagopt")) {
 448                 if (!strcmp(value, "--no-tags"))
 449                         remote->fetch_tags = -1;
 450                 else if (!strcmp(value, "--tags"))
 451                         remote->fetch_tags = 2;
 452         } else if (!strcmp(subkey, ".proxy")) {
 453                 return git_config_string((const char **)&remote->http_proxy,
 454                                          key, value);
 455         } else if (!strcmp(subkey, ".vcs")) {
 456                 return git_config_string(&remote->foreign_vcs, key, value);
 457         }
 458         return 0;
 459 }
 460
 461 static void alias_all_urls(void)
 462 {
 463         int i, j;
 464         for (i = 0; i < remotes_nr; i++) {
 465                 int add_pushurl_aliases;
 466                 if (!remotes[i])
 467                         continue;
 468                 for (j = 0; j < remotes[i]->pushurl_nr; j++) {
 469                         remotes[i]->pushurl[j] = alias_url(remotes[i]->pushurl[j], &rewrites);
 470                 }
 471                 add_pushurl_aliases = remotes[i]->pushurl_nr == 0;
 472                 for (j = 0; j < remotes[i]->url_nr; j++) {
 473                         if (add_pushurl_aliases)
 474                                 add_pushurl_alias(remotes[i], remotes[i]->url[j]);
 475                         remotes[i]->url[j] = alias_url(remotes[i]->url[j], &rewrites);
 476                 }
 477         }
 478 }
 479
 480 static void read_config(void)
 481 {
 482         unsigned char sha1[20];
 483         const char *head_ref;
 484         int flag;
 485         if (default_remote_name) /* did this already */
 486                 return;
 487         default_remote_name = "origin";
 488         current_branch = NULL;
 489         head_ref = resolve_ref_unsafe("HEAD", sha1, 0, &flag);
 490         if (head_ref && (flag & REF_ISSYMREF) &&
 491             !prefixcmp(head_ref, "refs/heads/")) {
 492                 current_branch =
 493                         make_branch(head_ref + strlen("refs/heads/"), 0);
 494         }
 495         git_config(handle_config, NULL);
 496         if (branch_pushremote_name) {
 497                 free((char *)pushremote_name);
 498                 pushremote_name = branch_pushremote_name;
 499         }
 500         alias_all_urls();
 501 }
 502
 503 /*
 504  * This function frees a refspec array.
 505  * Warning: code paths should be checked to ensure that the src
 506  *          and dst pointers are always freeable pointers as well
 507  *          as the refspec pointer itself.
 508  */
 509 static void free_refspecs(struct refspec *refspec, int nr_refspec)
 510 {
 511         int i;
 512
 513         if (!refspec)
 514                 return;
 515
 516         for (i = 0; i < nr_refspec; i++) {
 517                 free(refspec[i].src);
 518                 free(refspec[i].dst);
 519         }
 520         free(refspec);
 521 }
 522
 523 static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 524 {
 525         int i;
 526         struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 527
 528         for (i = 0; i < nr_refspec; i++) {
 529                 size_t llen;
 530                 int is_glob;
 531                 const char *lhs, *rhs;
 532                 int flags;
 533
 534                 is_glob = 0;
 535
 536                 lhs = refspec[i];
 537                 if (*lhs == '+') {
 538                         rs[i].force = 1;
 539                         lhs++;
 540                 }
 541
 542                 rhs = strrchr(lhs, ':');
 543
 544                 /*
 545                  * Before going on, special case ":" (or "+:") as a refspec
 546                  * for pushing matching refs.
 547                  */
 548                 if (!fetch && rhs == lhs && rhs[1] == '\0') {
 549                         rs[i].matching = 1;
 550                         continue;
 551                 }
 552
 553                 if (rhs) {
 554                         size_t rlen = strlen(++rhs);
 555                         is_glob = (1 <= rlen && strchr(rhs, '*'));
 556                         rs[i].dst = xstrndup(rhs, rlen);
 557                 }
 558
 559                 llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 560                 if (1 <= llen && memchr(lhs, '*', llen)) {
 561                         if ((rhs && !is_glob) || (!rhs && fetch))
 562                                 goto invalid;
 563                         is_glob = 1;
 564                 } else if (rhs && is_glob) {
 565                         goto invalid;
 566                 }
 567
 568                 rs[i].pattern = is_glob;
 569                 rs[i].src = xstrndup(lhs, llen);
 570                 flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 571
 572                 if (fetch) {
 573                         unsigned char unused[40];
 574
 575                         /* LHS */
 576                         if (!*rs[i].src)
 577                                 ; /* empty is ok; it means "HEAD" */
 578                         else if (llen == 40 && !get_sha1_hex(rs[i].src, unused))
 579                                 rs[i].exact_sha1 = 1; /* ok */
 580                         else if (!check_refname_format(rs[i].src, flags))
 581                                 ; /* valid looking ref is ok */
 582                         else
 583                                 goto invalid;
 584                         /* RHS */
 585                         if (!rs[i].dst)
 586                                 ; /* missing is ok; it is the same as empty */
 587                         else if (!*rs[i].dst)
 588                                 ; /* empty is ok; it means "do not store" */
 589                         else if (!check_refname_format(rs[i].dst, flags))
 590                                 ; /* valid looking ref is ok */
 591                         else
 592                                 goto invalid;
 593                 } else {
 594                         /*
 595                          * LHS
 596                          * - empty is allowed; it means delete.
 597                          * - when wildcarded, it must be a valid looking ref.
 598                          * - otherwise, it must be an extended SHA-1, but
 599                          *   there is no existing way to validate this.
 600                          */
 601                         if (!*rs[i].src)
 602                                 ; /* empty is ok */
 603                         else if (is_glob) {
 604                                 if (check_refname_format(rs[i].src, flags))
 605                                         goto invalid;
 606                         }
 607                         else
 608                                 ; /* anything goes, for now */
 609                         /*
 610                          * RHS
 611                          * - missing is allowed, but LHS then must be a
 612                          *   valid looking ref.
 613                          * - empty is not allowed.
 614                          * - otherwise it must be a valid looking ref.
 615                          */
 616                         if (!rs[i].dst) {
 617                                 if (check_refname_format(rs[i].src, flags))
 618                                         goto invalid;
 619                         } else if (!*rs[i].dst) {
 620                                 goto invalid;
 621                         } else {
 622                                 if (check_refname_format(rs[i].dst, flags))
 623                                         goto invalid;
 624                         }
 625                 }
 626         }
 627         return rs;
 628
 629  invalid:
 630         if (verify) {
 631                 /*
 632                  * nr_refspec must be greater than zero and i must be valid
 633                  * since it is only possible to reach this point from within
 634                  * the for loop above.
 635                  */
 636                 free_refspecs(rs, i+1);
 637                 return NULL;
 638         }
 639         die("Invalid refspec '%s'", refspec[i]);
 640 }
 641
 642 int valid_fetch_refspec(const char *fetch_refspec_str)
 643 {
 644         struct refspec *refspec;
 645
 646         refspec = parse_refspec_internal(1, &fetch_refspec_str, 1, 1);
 647         free_refspecs(refspec, 1);
 648         return !!refspec;
 649 }
 650
 651 struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 652 {
 653         return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 654 }
 655
 656 static struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 657 {
 658         return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 659 }
 660
 661 void free_refspec(int nr_refspec, struct refspec *refspec)
 662 {
 663         int i;
 664         for (i = 0; i < nr_refspec; i++) {
 665                 free(refspec[i].src);
 666                 free(refspec[i].dst);
 667         }
 668         free(refspec);
 669 }
 670
 671 static int valid_remote_nick(const char *name)
 672 {
 673         if (!name[0] || is_dot_or_dotdot(name))
 674                 return 0;
 675         return !strchr(name, '/'); /* no slash */
 676 }
 677
 678 static struct remote *remote_get_1(const char *name, const char *pushremote_name)
 679 {
 680         struct remote *ret;
 681         int name_given = 0;
 682
 683         if (name)
 684                 name_given = 1;
 685         else {
 686                 if (pushremote_name) {
 687                         name = pushremote_name;
 688                         name_given = 1;
 689                 } else {
 690                         name = default_remote_name;
 691                         name_given = explicit_default_remote_name;
 692                 }
 693         }
 694
 695         ret = make_remote(name, 0);
 696         if (valid_remote_nick(name)) {
 697                 if (!valid_remote(ret))
 698                         read_remotes_file(ret);
 699                 if (!valid_remote(ret))
 700                         read_branches_file(ret);
 701         }
 702         if (name_given && !valid_remote(ret))
 703                 add_url_alias(ret, name);
 704         if (!valid_remote(ret))
 705                 return NULL;
 706         ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 707         ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 708         return ret;
 709 }
 710
 711 struct remote *remote_get(const char *name)
 712 {
 713         read_config();
 714         return remote_get_1(name, NULL);
 715 }
 716
 717 struct remote *pushremote_get(const char *name)
 718 {
 719         read_config();
 720         return remote_get_1(name, pushremote_name);
 721 }
 722
 723 int remote_is_configured(const char *name)
 724 {
 725         int i;
 726         read_config();
 727
 728         for (i = 0; i < remotes_nr; i++)
 729                 if (!strcmp(name, remotes[i]->name))
 730                         return 1;
 731         return 0;
 732 }
 733
 734 int for_each_remote(each_remote_fn fn, void *priv)
 735 {
 736         int i, result = 0;
 737         read_config();
 738         for (i = 0; i < remotes_nr && !result; i++) {
 739                 struct remote *r = remotes[i];
 740                 if (!r)
 741                         continue;
 742                 if (!r->fetch)
 743                         r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 744                                                        r->fetch_refspec);
 745                 if (!r->push)
 746                         r->push = parse_push_refspec(r->push_refspec_nr,
 747                                                      r->push_refspec);
 748                 result = fn(r, priv);
 749         }
 750         return result;
 751 }
 752
 753 void ref_remove_duplicates(struct ref *ref_map)
 754 {
 755         struct string_list refs = STRING_LIST_INIT_NODUP;
 756         struct string_list_item *item = NULL;
 757         struct ref *prev = NULL, *next = NULL;
 758         for (; ref_map; prev = ref_map, ref_map = next) {
 759                 next = ref_map->next;
 760                 if (!ref_map->peer_ref)
 761                         continue;
 762
 763                 item = string_list_lookup(&refs, ref_map->peer_ref->name);
 764                 if (item) {
 765                         if (strcmp(((struct ref *)item->util)->name,
 766                                    ref_map->name))
 767                                 die("%s tracks both %s and %s",
 768                                     ref_map->peer_ref->name,
 769                                     ((struct ref *)item->util)->name,
 770                                     ref_map->name);
 771                         prev->next = ref_map->next;
 772                         free(ref_map->peer_ref);
 773                         free(ref_map);
 774                         ref_map = prev; /* skip this; we freed it */
 775                         continue;
 776                 }
 777
 778                 item = string_list_insert(&refs, ref_map->peer_ref->name);
 779                 item->util = ref_map;
 780         }
 781         string_list_clear(&refs, 0);
 782 }
 783
 784 int remote_has_url(struct remote *remote, const char *url)
 785 {
 786         int i;
 787         for (i = 0; i < remote->url_nr; i++) {
 788                 if (!strcmp(remote->url[i], url))
 789                         return 1;
 790         }
 791         return 0;
 792 }
 793
 794 static int match_name_with_pattern(const char *key, const char *name,
 795                                    const char *value, char **result)
 796 {
 797         const char *kstar = strchr(key, '*');
 798         size_t klen;
 799         size_t ksuffixlen;
 800         size_t namelen;
 801         int ret;
 802         if (!kstar)
 803                 die("Key '%s' of pattern had no '*'", key);
 804         klen = kstar - key;
 805         ksuffixlen = strlen(kstar + 1);
 806         namelen = strlen(name);
 807         ret = !strncmp(name, key, klen) && namelen >= klen + ksuffixlen &&
 808                 !memcmp(name + namelen - ksuffixlen, kstar + 1, ksuffixlen);
 809         if (ret && value) {
 810                 const char *vstar = strchr(value, '*');
 811                 size_t vlen;
 812                 size_t vsuffixlen;
 813                 if (!vstar)
 814                         die("Value '%s' of pattern has no '*'", value);
 815                 vlen = vstar - value;
 816                 vsuffixlen = strlen(vstar + 1);
 817                 *result = xmalloc(vlen + vsuffixlen +
 818                                   strlen(name) -
 819                                   klen - ksuffixlen + 1);
 820                 strncpy(*result, value, vlen);
 821                 strncpy(*result + vlen,
 822                         name + klen, namelen - klen - ksuffixlen);
 823                 strcpy(*result + vlen + namelen - klen - ksuffixlen,
 824                        vstar + 1);
 825         }
 826         return ret;
 827 }
 828
 829 static int query_refspecs(struct refspec *refs, int ref_count, struct refspec *query)
 830 {
 831         int i;
 832         int find_src = !query->src;
 833
 834         if (find_src && !query->dst)
 835                 return error("query_refspecs: need either src or dst");
 836
 837         for (i = 0; i < ref_count; i++) {
 838                 struct refspec *refspec = &refs[i];
 839                 const char *key = find_src ? refspec->dst : refspec->src;
 840                 const char *value = find_src ? refspec->src : refspec->dst;
 841                 const char *needle = find_src ? query->dst : query->src;
 842                 char **result = find_src ? &query->src : &query->dst;
 843
 844                 if (!refspec->dst)
 845                         continue;
 846                 if (refspec->pattern) {
 847                         if (match_name_with_pattern(key, needle, value, result)) {
 848                                 query->force = refspec->force;
 849                                 return 0;
 850                         }
 851                 } else if (!strcmp(needle, key)) {
 852                         *result = xstrdup(value);
 853                         query->force = refspec->force;
 854                         return 0;
 855                 }
 856         }
 857         return -1;
 858 }
 859
 860 char *apply_refspecs(struct refspec *refspecs, int nr_refspec,
 861                      const char *name)
 862 {
 863         struct refspec query;
 864
 865         memset(&query, 0, sizeof(struct refspec));
 866         query.src = (char *)name;
 867
 868         if (query_refspecs(refspecs, nr_refspec, &query))
 869                 return NULL;
 870
 871         return query.dst;
 872 }
 873
 874 int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 875 {
 876         return query_refspecs(remote->fetch, remote->fetch_refspec_nr, refspec);
 877 }
 878
 879 static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 880                 const char *name)
 881 {
 882         size_t len = strlen(name);
 883         struct ref *ref = xcalloc(1, sizeof(struct ref) + prefixlen + len + 1);
 884         memcpy(ref->name, prefix, prefixlen);
 885         memcpy(ref->name + prefixlen, name, len);
 886         return ref;
 887 }
 888
 889 struct ref *alloc_ref(const char *name)
 890 {
 891         return alloc_ref_with_prefix("", 0, name);
 892 }
 893
 894 struct ref *copy_ref(const struct ref *ref)
 895 {
 896         struct ref *cpy;
 897         size_t len;
 898         if (!ref)
 899                 return NULL;
 900         len = strlen(ref->name);
 901         cpy = xmalloc(sizeof(struct ref) + len + 1);
 902         memcpy(cpy, ref, sizeof(struct ref) + len + 1);
 903         cpy->next = NULL;
 904         cpy->symref = ref->symref ? xstrdup(ref->symref) : NULL;
 905         cpy->remote_status = ref->remote_status ? xstrdup(ref->remote_status) : NULL;
 906         cpy->peer_ref = copy_ref(ref->peer_ref);
 907         return cpy;
 908 }
 909
 910 struct ref *copy_ref_list(const struct ref *ref)
 911 {
 912         struct ref *ret = NULL;
 913         struct ref **tail = &ret;
 914         while (ref) {
 915                 *tail = copy_ref(ref);
 916                 ref = ref->next;
 917                 tail = &((*tail)->next);
 918         }
 919         return ret;
 920 }
 921
 922 static void free_ref(struct ref *ref)
 923 {
 924         if (!ref)
 925                 return;
 926         free_ref(ref->peer_ref);
 927         free(ref->remote_status);
 928         free(ref->symref);
 929         free(ref);
 930 }
 931
 932 void free_refs(struct ref *ref)
 933 {
 934         struct ref *next;
 935         while (ref) {
 936                 next = ref->next;
 937                 free_ref(ref);
 938                 ref = next;
 939         }
 940 }
 941
 942 int ref_compare_name(const void *va, const void *vb)
 943 {
 944         const struct ref *a = va, *b = vb;
 945         return strcmp(a->name, b->name);
 946 }
 947
 948 static void *ref_list_get_next(const void *a)
 949 {
 950         return ((const struct ref *)a)->next;
 951 }
 952
 953 static void ref_list_set_next(void *a, void *next)
 954 {
 955         ((struct ref *)a)->next = next;
 956 }
 957
 958 void sort_ref_list(struct ref **l, int (*cmp)(const void *, const void *))
 959 {
 960         *l = llist_mergesort(*l, ref_list_get_next, ref_list_set_next, cmp);
 961 }
 962
 963 static int count_refspec_match(const char *pattern,
 964                                struct ref *refs,
 965                                struct ref **matched_ref)
 966 {
 967         int patlen = strlen(pattern);
 968         struct ref *matched_weak = NULL;
 969         struct ref *matched = NULL;
 970         int weak_match = 0;
 971         int match = 0;
 972
 973         for (weak_match = match = 0; refs; refs = refs->next) {
 974                 char *name = refs->name;
 975                 int namelen = strlen(name);
 976
 977                 if (!refname_match(pattern, name, ref_rev_parse_rules))
 978                         continue;
 979
 980                 /* A match is "weak" if it is with refs outside
 981                  * heads or tags, and did not specify the pattern
 982                  * in full (e.g. "refs/remotes/origin/master") or at
 983                  * least from the toplevel (e.g. "remotes/origin/master");
 984                  * otherwise "git push $URL master" would result in
 985                  * ambiguity between remotes/origin/master and heads/master
 986                  * at the remote site.
 987                  */
 988                 if (namelen != patlen &&
 989                     patlen != namelen - 5 &&
 990                     prefixcmp(name, "refs/heads/") &&
 991                     prefixcmp(name, "refs/tags/")) {
 992                         /* We want to catch the case where only weak
 993                          * matches are found and there are multiple
 994                          * matches, and where more than one strong
 995                          * matches are found, as ambiguous.  One
 996                          * strong match with zero or more weak matches
 997                          * are acceptable as a unique match.
 998                          */
 999                         matched_weak = refs;
1000                         weak_match++;
1001                 }
1002                 else {
1003                         matched = refs;
1004                         match++;
1005                 }
1006         }
1007         if (!matched) {
1008                 *matched_ref = matched_weak;
1009                 return weak_match;
1010         }
1011         else {
1012                 *matched_ref = matched;
1013                 return match;
1014         }
1015 }
1016
1017 static void tail_link_ref(struct ref *ref, struct ref ***tail)
1018 {
1019         **tail = ref;
1020         while (ref->next)
1021                 ref = ref->next;
1022         *tail = &ref->next;
1023 }
1024
1025 static struct ref *alloc_delete_ref(void)
1026 {
1027         struct ref *ref = alloc_ref("(delete)");
1028         hashclr(ref->new_sha1);
1029         return ref;
1030 }
1031
1032 static struct ref *try_explicit_object_name(const char *name)
1033 {
1034         unsigned char sha1[20];
1035         struct ref *ref;
1036
1037         if (!*name)
1038                 return alloc_delete_ref();
1039         if (get_sha1(name, sha1))
1040                 return NULL;
1041         ref = alloc_ref(name);
1042         hashcpy(ref->new_sha1, sha1);
1043         return ref;
1044 }
1045
1046 static struct ref *make_linked_ref(const char *name, struct ref ***tail)
1047 {
1048         struct ref *ret = alloc_ref(name);
1049         tail_link_ref(ret, tail);
1050         return ret;
1051 }
1052
1053 static char *guess_ref(const char *name, struct ref *peer)
1054 {
1055         struct strbuf buf = STRBUF_INIT;
1056         unsigned char sha1[20];
1057
1058         const char *r = resolve_ref_unsafe(peer->name, sha1, 1, NULL);
1059         if (!r)
1060                 return NULL;
1061
1062         if (!prefixcmp(r, "refs/heads/"))
1063                 strbuf_addstr(&buf, "refs/heads/");
1064         else if (!prefixcmp(r, "refs/tags/"))
1065                 strbuf_addstr(&buf, "refs/tags/");
1066         else
1067                 return NULL;
1068
1069         strbuf_addstr(&buf, name);
1070         return strbuf_detach(&buf, NULL);
1071 }
1072
1073 static int match_explicit(struct ref *src, struct ref *dst,
1074                           struct ref ***dst_tail,
1075                           struct refspec *rs)
1076 {
1077         struct ref *matched_src, *matched_dst;
1078         int copy_src;
1079
1080         const char *dst_value = rs->dst;
1081         char *dst_guess;
1082
1083         if (rs->pattern || rs->matching)
1084                 return 0;
1085
1086         matched_src = matched_dst = NULL;
1087         switch (count_refspec_match(rs->src, src, &matched_src)) {
1088         case 1:
1089                 copy_src = 1;
1090                 break;
1091         case 0:
1092                 /* The source could be in the get_sha1() format
1093                  * not a reference name.  :refs/other is a
1094                  * way to delete 'other' ref at the remote end.
1095                  */
1096                 matched_src = try_explicit_object_name(rs->src);
1097                 if (!matched_src)
1098                         return error("src refspec %s does not match any.", rs->src);
1099                 copy_src = 0;
1100                 break;
1101         default:
1102                 return error("src refspec %s matches more than one.", rs->src);
1103         }
1104
1105         if (!dst_value) {
1106                 unsigned char sha1[20];
1107                 int flag;
1108
1109                 dst_value = resolve_ref_unsafe(matched_src->name, sha1, 1, &flag);
1110                 if (!dst_value ||
1111                     ((flag & REF_ISSYMREF) &&
1112                      prefixcmp(dst_value, "refs/heads/")))
1113                         die("%s cannot be resolved to branch.",
1114                             matched_src->name);
1115         }
1116
1117         switch (count_refspec_match(dst_value, dst, &matched_dst)) {
1118         case 1:
1119                 break;
1120         case 0:
1121                 if (!memcmp(dst_value, "refs/", 5))
1122                         matched_dst = make_linked_ref(dst_value, dst_tail);
1123                 else if (is_null_sha1(matched_src->new_sha1))
1124                         error("unable to delete '%s': remote ref does not exist",
1125                               dst_value);
1126                 else if ((dst_guess = guess_ref(dst_value, matched_src)))
1127                         matched_dst = make_linked_ref(dst_guess, dst_tail);
1128                 else
1129                         error("unable to push to unqualified destination: %s\n"
1130                               "The destination refspec neither matches an "
1131                               "existing ref on the remote nor\n"
1132                               "begins with refs/, and we are unable to "
1133                               "guess a prefix based on the source ref.",
1134                               dst_value);
1135                 break;
1136         default:
1137                 matched_dst = NULL;
1138                 error("dst refspec %s matches more than one.",
1139                       dst_value);
1140                 break;
1141         }
1142         if (!matched_dst)
1143                 return -1;
1144         if (matched_dst->peer_ref)
1145                 return error("dst ref %s receives from more than one src.",
1146                       matched_dst->name);
1147         else {
1148                 matched_dst->peer_ref = copy_src ? copy_ref(matched_src) : matched_src;
1149                 matched_dst->force = rs->force;
1150         }
1151         return 0;
1152 }
1153
1154 static int match_explicit_refs(struct ref *src, struct ref *dst,
1155                                struct ref ***dst_tail, struct refspec *rs,
1156                                int rs_nr)
1157 {
1158         int i, errs;
1159         for (i = errs = 0; i < rs_nr; i++)
1160                 errs += match_explicit(src, dst, dst_tail, &rs[i]);
1161         return errs;
1162 }
1163
1164 static char *get_ref_match(const struct refspec *rs, int rs_nr, const struct ref *ref,
1165                 int send_mirror, int direction, const struct refspec **ret_pat)
1166 {
1167         const struct refspec *pat;
1168         char *name;
1169         int i;
1170         int matching_refs = -1;
1171         for (i = 0; i < rs_nr; i++) {
1172                 if (rs[i].matching &&
1173                     (matching_refs == -1 || rs[i].force)) {
1174                         matching_refs = i;
1175                         continue;
1176                 }
1177
1178                 if (rs[i].pattern) {
1179                         const char *dst_side = rs[i].dst ? rs[i].dst : rs[i].src;
1180                         int match;
1181                         if (direction == FROM_SRC)
1182                                 match = match_name_with_pattern(rs[i].src, ref->name, dst_side, &name);
1183                         else
1184                                 match = match_name_with_pattern(dst_side, ref->name, rs[i].src, &name);
1185                         if (match) {
1186                                 matching_refs = i;
1187                                 break;
1188                         }
1189                 }
1190         }
1191         if (matching_refs == -1)
1192                 return NULL;
1193
1194         pat = rs + matching_refs;
1195         if (pat->matching) {
1196                 /*
1197                  * "matching refs"; traditionally we pushed everything
1198                  * including refs outside refs/heads/ hierarchy, but
1199                  * that does not make much sense these days.
1200                  */
1201                 if (!send_mirror && prefixcmp(ref->name, "refs/heads/"))
1202                         return NULL;
1203                 name = xstrdup(ref->name);
1204         }
1205         if (ret_pat)
1206                 *ret_pat = pat;
1207         return name;
1208 }
1209
1210 static struct ref **tail_ref(struct ref **head)
1211 {
1212         struct ref **tail = head;
1213         while (*tail)
1214                 tail = &((*tail)->next);
1215         return tail;
1216 }
1217
1218 struct tips {
1219         struct commit **tip;
1220         int nr, alloc;
1221 };
1222
1223 static void add_to_tips(struct tips *tips, const unsigned char *sha1)
1224 {
1225         struct commit *commit;
1226
1227         if (is_null_sha1(sha1))
1228                 return;
1229         commit = lookup_commit_reference_gently(sha1, 1);
1230         if (!commit || (commit->object.flags & TMP_MARK))
1231                 return;
1232         commit->object.flags |= TMP_MARK;
1233         ALLOC_GROW(tips->tip, tips->nr + 1, tips->alloc);
1234         tips->tip[tips->nr++] = commit;
1235 }
1236
1237 static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***dst_tail)
1238 {
1239         struct string_list dst_tag = STRING_LIST_INIT_NODUP;
1240         struct string_list src_tag = STRING_LIST_INIT_NODUP;
1241         struct string_list_item *item;
1242         struct ref *ref;
1243         struct tips sent_tips;
1244
1245         /*
1246          * Collect everything we know they would have at the end of
1247          * this push, and collect all tags they have.
1248          */
1249         memset(&sent_tips, 0, sizeof(sent_tips));
1250         for (ref = *dst; ref; ref = ref->next) {
1251                 if (ref->peer_ref &&
1252                     !is_null_sha1(ref->peer_ref->new_sha1))
1253                         add_to_tips(&sent_tips, ref->peer_ref->new_sha1);
1254                 else
1255                         add_to_tips(&sent_tips, ref->old_sha1);
1256                 if (!prefixcmp(ref->name, "refs/tags/"))
1257                         string_list_append(&dst_tag, ref->name);
1258         }
1259         clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
1260
1261         sort_string_list(&dst_tag);
1262
1263         /* Collect tags they do not have. */
1264         for (ref = src; ref; ref = ref->next) {
1265                 if (prefixcmp(ref->name, "refs/tags/"))
1266                         continue; /* not a tag */
1267                 if (string_list_has_string(&dst_tag, ref->name))
1268                         continue; /* they already have it */
1269                 if (sha1_object_info(ref->new_sha1, NULL) != OBJ_TAG)
1270                         continue; /* be conservative */
1271                 item = string_list_append(&src_tag, ref->name);
1272                 item->util = ref;
1273         }
1274         string_list_clear(&dst_tag, 0);
1275
1276         /*
1277          * At this point, src_tag lists tags that are missing from
1278          * dst, and sent_tips lists the tips we are pushing or those
1279          * that we know they already have. An element in the src_tag
1280          * that is an ancestor of any of the sent_tips needs to be
1281          * sent to the other side.
1282          */
1283         if (sent_tips.nr) {
1284                 for_each_string_list_item(item, &src_tag) {
1285                         struct ref *ref = item->util;
1286                         struct ref *dst_ref;
1287                         struct commit *commit;
1288
1289                         if (is_null_sha1(ref->new_sha1))
1290                                 continue;
1291                         commit = lookup_commit_reference_gently(ref->new_sha1, 1);
1292                         if (!commit)
1293                                 /* not pushing a commit, which is not an error */
1294                                 continue;
1295
1296                         /*
1297                          * Is this tag, which they do not have, reachable from
1298                          * any of the commits we are sending?
1299                          */
1300                         if (!in_merge_bases_many(commit, sent_tips.nr, sent_tips.tip))
1301                                 continue;
1302
1303                         /* Add it in */
1304                         dst_ref = make_linked_ref(ref->name, dst_tail);
1305                         hashcpy(dst_ref->new_sha1, ref->new_sha1);
1306                         dst_ref->peer_ref = copy_ref(ref);
1307                 }
1308         }
1309         string_list_clear(&src_tag, 0);
1310         free(sent_tips.tip);
1311 }
1312
1313 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1314 {
1315         for ( ; list; list = list->next)
1316                 if (!strcmp(list->name, name))
1317                         return (struct ref *)list;
1318         return NULL;
1319 }
1320
1321 static void prepare_ref_index(struct string_list *ref_index, struct ref *ref)
1322 {
1323         for ( ; ref; ref = ref->next)
1324                 string_list_append_nodup(ref_index, ref->name)->util = ref;
1325
1326         sort_string_list(ref_index);
1327 }
1328
1329 /*
1330  * Given the set of refs the local repository has, the set of refs the
1331  * remote repository has, and the refspec used for push, determine
1332  * what remote refs we will update and with what value by setting
1333  * peer_ref (which object is being pushed) and force (if the push is
1334  * forced) in elements of "dst". The function may add new elements to
1335  * dst (e.g. pushing to a new branch, done in match_explicit_refs).
1336  */
1337 int match_push_refs(struct ref *src, struct ref **dst,
1338                     int nr_refspec, const char **refspec, int flags)
1339 {
1340         struct refspec *rs;
1341         int send_all = flags & MATCH_REFS_ALL;
1342         int send_mirror = flags & MATCH_REFS_MIRROR;
1343         int send_prune = flags & MATCH_REFS_PRUNE;
1344         int errs;
1345         static const char *default_refspec[] = { ":", NULL };
1346         struct ref *ref, **dst_tail = tail_ref(dst);
1347         struct string_list dst_ref_index = STRING_LIST_INIT_NODUP;
1348
1349         if (!nr_refspec) {
1350                 nr_refspec = 1;
1351                 refspec = default_refspec;
1352         }
1353         rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1354         errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
1355
1356         /* pick the remainder */
1357         for (ref = src; ref; ref = ref->next) {
1358                 struct string_list_item *dst_item;
1359                 struct ref *dst_peer;
1360                 const struct refspec *pat = NULL;
1361                 char *dst_name;
1362
1363                 dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
1364                 if (!dst_name)
1365                         continue;
1366
1367                 if (!dst_ref_index.nr)
1368                         prepare_ref_index(&dst_ref_index, *dst);
1369
1370                 dst_item = string_list_lookup(&dst_ref_index, dst_name);
1371                 dst_peer = dst_item ? dst_item->util : NULL;
1372                 if (dst_peer) {
1373                         if (dst_peer->peer_ref)
1374                                 /* We're already sending something to this ref. */
1375                                 goto free_name;
1376                 } else {
1377                         if (pat->matching && !(send_all || send_mirror))
1378                                 /*
1379                                  * Remote doesn't have it, and we have no
1380                                  * explicit pattern, and we don't have
1381                                  * --all nor --mirror.
1382                                  */
1383                                 goto free_name;
1384
1385                         /* Create a new one and link it */
1386                         dst_peer = make_linked_ref(dst_name, &dst_tail);
1387                         hashcpy(dst_peer->new_sha1, ref->new_sha1);
1388                         string_list_insert(&dst_ref_index,
1389                                 dst_peer->name)->util = dst_peer;
1390                 }
1391                 dst_peer->peer_ref = copy_ref(ref);
1392                 dst_peer->force = pat->force;
1393         free_name:
1394                 free(dst_name);
1395         }
1396
1397         string_list_clear(&dst_ref_index, 0);
1398
1399         if (flags & MATCH_REFS_FOLLOW_TAGS)
1400                 add_missing_tags(src, dst, &dst_tail);
1401
1402         if (send_prune) {
1403                 struct string_list src_ref_index = STRING_LIST_INIT_NODUP;
1404                 /* check for missing refs on the remote */
1405                 for (ref = *dst; ref; ref = ref->next) {
1406                         char *src_name;
1407
1408                         if (ref->peer_ref)
1409                                 /* We're already sending something to this ref. */
1410                                 continue;
1411
1412                         src_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_DST, NULL);
1413                         if (src_name) {
1414                                 if (!src_ref_index.nr)
1415                                         prepare_ref_index(&src_ref_index, src);
1416                                 if (!string_list_has_string(&src_ref_index,
1417                                             src_name))
1418                                         ref->peer_ref = alloc_delete_ref();
1419                                 free(src_name);
1420                         }
1421                 }
1422                 string_list_clear(&src_ref_index, 0);
1423         }
1424         if (errs)
1425                 return -1;
1426         return 0;
1427 }
1428
1429 void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
1430                              int force_update)
1431 {
1432         struct ref *ref;
1433
1434         for (ref = remote_refs; ref; ref = ref->next) {
1435                 int force_ref_update = ref->force || force_update;
1436                 int reject_reason = 0;
1437
1438                 if (ref->peer_ref)
1439                         hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
1440                 else if (!send_mirror)
1441                         continue;
1442
1443                 ref->deletion = is_null_sha1(ref->new_sha1);
1444                 if (!ref->deletion &&
1445                         !hashcmp(ref->old_sha1, ref->new_sha1)) {
1446                         ref->status = REF_STATUS_UPTODATE;
1447                         continue;
1448                 }
1449
1450                 /*
1451                  * Bypass the usual "must fast-forward" check but
1452                  * replace it with a weaker "the old value must be
1453                  * this value we observed".  If the remote ref has
1454                  * moved and is now different from what we expect,
1455                  * reject any push.
1456                  *
1457                  * It also is an error if the user told us to check
1458                  * with the remote-tracking branch to find the value
1459                  * to expect, but we did not have such a tracking
1460                  * branch.
1461                  */
1462                 if (ref->expect_old_sha1) {
1463                         if (ref->expect_old_no_trackback ||
1464                             hashcmp(ref->old_sha1, ref->old_sha1_expect))
1465                                 reject_reason = REF_STATUS_REJECT_STALE;
1466                 }
1467
1468                 /*
1469                  * The usual "must fast-forward" rules.
1470                  *
1471                  * Decide whether an individual refspec A:B can be
1472                  * pushed.  The push will succeed if any of the
1473                  * following are true:
1474                  *
1475                  * (1) the remote reference B does not exist
1476                  *
1477                  * (2) the remote reference B is being removed (i.e.,
1478                  *     pushing :B where no source is specified)
1479                  *
1480                  * (3) the destination is not under refs/tags/, and
1481                  *     if the old and new value is a commit, the new
1482                  *     is a descendant of the old.
1483                  *
1484                  * (4) it is forced using the +A:B notation, or by
1485                  *     passing the --force argument
1486                  */
1487
1488                 else if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
1489                         if (!prefixcmp(ref->name, "refs/tags/"))
1490                                 reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
1491                         else if (!has_sha1_file(ref->old_sha1))
1492                                 reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
1493                         else if (!lookup_commit_reference_gently(ref->old_sha1, 1) ||
1494                                  !lookup_commit_reference_gently(ref->new_sha1, 1))
1495                                 reject_reason = REF_STATUS_REJECT_NEEDS_FORCE;
1496                         else if (!ref_newer(ref->new_sha1, ref->old_sha1))
1497                                 reject_reason = REF_STATUS_REJECT_NONFASTFORWARD;
1498                 }
1499
1500                 /*
1501                  * "--force" will defeat any rejection implemented
1502                  * by the rules above.
1503                  */
1504                 if (!force_ref_update)
1505                         ref->status = reject_reason;
1506                 else if (reject_reason)
1507                         ref->forced_update = 1;
1508         }
1509 }
1510
1511 struct branch *branch_get(const char *name)
1512 {
1513         struct branch *ret;
1514
1515         read_config();
1516         if (!name || !*name || !strcmp(name, "HEAD"))
1517                 ret = current_branch;
1518         else
1519                 ret = make_branch(name, 0);
1520         if (ret && ret->remote_name) {
1521                 ret->remote = remote_get(ret->remote_name);
1522                 if (ret->merge_nr) {
1523                         int i;
1524                         ret->merge = xcalloc(ret->merge_nr, sizeof(*ret->merge));
1525                         for (i = 0; i < ret->merge_nr; i++) {
1526                                 ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1527                                 ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1528                                 if (remote_find_tracking(ret->remote, ret->merge[i])
1529                                     && !strcmp(ret->remote_name, "."))
1530                                         ret->merge[i]->dst = xstrdup(ret->merge_name[i]);
1531                         }
1532                 }
1533         }
1534         return ret;
1535 }
1536
1537 int branch_has_merge_config(struct branch *branch)
1538 {
1539         return branch && !!branch->merge;
1540 }
1541
1542 int branch_merge_matches(struct branch *branch,
1543                                  int i,
1544                                  const char *refname)
1545 {
1546         if (!branch || i < 0 || i >= branch->merge_nr)
1547                 return 0;
1548         return refname_match(branch->merge[i]->src, refname, ref_fetch_rules);
1549 }
1550
1551 static int ignore_symref_update(const char *refname)
1552 {
1553         unsigned char sha1[20];
1554         int flag;
1555
1556         if (!resolve_ref_unsafe(refname, sha1, 0, &flag))
1557                 return 0; /* non-existing refs are OK */
1558         return (flag & REF_ISSYMREF);
1559 }
1560
1561 static struct ref *get_expanded_map(const struct ref *remote_refs,
1562                                     const struct refspec *refspec)
1563 {
1564         const struct ref *ref;
1565         struct ref *ret = NULL;
1566         struct ref **tail = &ret;
1567
1568         char *expn_name;
1569
1570         for (ref = remote_refs; ref; ref = ref->next) {
1571                 if (strchr(ref->name, '^'))
1572                         continue; /* a dereference item */
1573                 if (match_name_with_pattern(refspec->src, ref->name,
1574                                             refspec->dst, &expn_name) &&
1575                     !ignore_symref_update(expn_name)) {
1576                         struct ref *cpy = copy_ref(ref);
1577
1578                         cpy->peer_ref = alloc_ref(expn_name);
1579                         free(expn_name);
1580                         if (refspec->force)
1581                                 cpy->peer_ref->force = 1;
1582                         *tail = cpy;
1583                         tail = &cpy->next;
1584                 }
1585         }
1586
1587         return ret;
1588 }
1589
1590 static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1591 {
1592         const struct ref *ref;
1593         for (ref = refs; ref; ref = ref->next) {
1594                 if (refname_match(name, ref->name, ref_fetch_rules))
1595                         return ref;
1596         }
1597         return NULL;
1598 }
1599
1600 struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1601 {
1602         const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1603
1604         if (!ref)
1605                 return NULL;
1606
1607         return copy_ref(ref);
1608 }
1609
1610 static struct ref *get_local_ref(const char *name)
1611 {
1612         if (!name || name[0] == '\0')
1613                 return NULL;
1614
1615         if (!prefixcmp(name, "refs/"))
1616                 return alloc_ref(name);
1617
1618         if (!prefixcmp(name, "heads/") ||
1619             !prefixcmp(name, "tags/") ||
1620             !prefixcmp(name, "remotes/"))
1621                 return alloc_ref_with_prefix("refs/", 5, name);
1622
1623         return alloc_ref_with_prefix("refs/heads/", 11, name);
1624 }
1625
1626 int get_fetch_map(const struct ref *remote_refs,
1627                   const struct refspec *refspec,
1628                   struct ref ***tail,
1629                   int missing_ok)
1630 {
1631         struct ref *ref_map, **rmp;
1632
1633         if (refspec->pattern) {
1634                 ref_map = get_expanded_map(remote_refs, refspec);
1635         } else {
1636                 const char *name = refspec->src[0] ? refspec->src : "HEAD";
1637
1638                 if (refspec->exact_sha1) {
1639                         ref_map = alloc_ref(name);
1640                         get_sha1_hex(name, ref_map->old_sha1);
1641                 } else {
1642                         ref_map = get_remote_ref(remote_refs, name);
1643                 }
1644                 if (!missing_ok && !ref_map)
1645                         die("Couldn't find remote ref %s", name);
1646                 if (ref_map) {
1647                         ref_map->peer_ref = get_local_ref(refspec->dst);
1648                         if (ref_map->peer_ref && refspec->force)
1649                                 ref_map->peer_ref->force = 1;
1650                 }
1651         }
1652
1653         for (rmp = &ref_map; *rmp; ) {
1654                 if ((*rmp)->peer_ref) {
1655                         if (prefixcmp((*rmp)->peer_ref->name, "refs/") ||
1656                             check_refname_format((*rmp)->peer_ref->name, 0)) {
1657                                 struct ref *ignore = *rmp;
1658                                 error("* Ignoring funny ref '%s' locally",
1659                                       (*rmp)->peer_ref->name);
1660                                 *rmp = (*rmp)->next;
1661                                 free(ignore->peer_ref);
1662                                 free(ignore);
1663                                 continue;
1664                         }
1665                 }
1666                 rmp = &((*rmp)->next);
1667         }
1668
1669         if (ref_map)
1670                 tail_link_ref(ref_map, tail);
1671
1672         return 0;
1673 }
1674
1675 int resolve_remote_symref(struct ref *ref, struct ref *list)
1676 {
1677         if (!ref->symref)
1678                 return 0;
1679         for (; list; list = list->next)
1680                 if (!strcmp(ref->symref, list->name)) {
1681                         hashcpy(ref->old_sha1, list->old_sha1);
1682                         return 0;
1683                 }
1684         return 1;
1685 }
1686
1687 static void unmark_and_free(struct commit_list *list, unsigned int mark)
1688 {
1689         while (list) {
1690                 struct commit_list *temp = list;
1691                 temp->item->object.flags &= ~mark;
1692                 list = temp->next;
1693                 free(temp);
1694         }
1695 }
1696
1697 int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
1698 {
1699         struct object *o;
1700         struct commit *old, *new;
1701         struct commit_list *list, *used;
1702         int found = 0;
1703
1704         /*
1705          * Both new and old must be commit-ish and new is descendant of
1706          * old.  Otherwise we require --force.
1707          */
1708         o = deref_tag(parse_object(old_sha1), NULL, 0);
1709         if (!o || o->type != OBJ_COMMIT)
1710                 return 0;
1711         old = (struct commit *) o;
1712
1713         o = deref_tag(parse_object(new_sha1), NULL, 0);
1714         if (!o || o->type != OBJ_COMMIT)
1715                 return 0;
1716         new = (struct commit *) o;
1717
1718         if (parse_commit(new) < 0)
1719                 return 0;
1720
1721         used = list = NULL;
1722         commit_list_insert(new, &list);
1723         while (list) {
1724                 new = pop_most_recent_commit(&list, TMP_MARK);
1725                 commit_list_insert(new, &used);
1726                 if (new == old) {
1727                         found = 1;
1728                         break;
1729                 }
1730         }
1731         unmark_and_free(list, TMP_MARK);
1732         unmark_and_free(used, TMP_MARK);
1733         return found;
1734 }
1735
1736 /*
1737  * Compare a branch with its upstream, and save their differences (number
1738  * of commits) in *num_ours and *num_theirs.
1739  *
1740  * Return 0 if branch has no upstream (no base), -1 if upstream is missing
1741  * (with "gone" base), otherwise 1 (with base).
1742  */
1743 int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
1744 {
1745         unsigned char sha1[20];
1746         struct commit *ours, *theirs;
1747         char symmetric[84];
1748         struct rev_info revs;
1749         const char *rev_argv[10], *base;
1750         int rev_argc;
1751
1752         /* Cannot stat unless we are marked to build on top of somebody else. */
1753         if (!branch ||
1754             !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
1755                 return 0;
1756
1757         /* Cannot stat if what we used to build on no longer exists */
1758         base = branch->merge[0]->dst;
1759         if (read_ref(base, sha1))
1760                 return -1;
1761         theirs = lookup_commit_reference(sha1);
1762         if (!theirs)
1763                 return -1;
1764
1765         if (read_ref(branch->refname, sha1))
1766                 return -1;
1767         ours = lookup_commit_reference(sha1);
1768         if (!ours)
1769                 return -1;
1770
1771         /* are we the same? */
1772         if (theirs == ours) {
1773                 *num_theirs = *num_ours = 0;
1774                 return 1;
1775         }
1776
1777         /* Run "rev-list --left-right ours...theirs" internally... */
1778         rev_argc = 0;
1779         rev_argv[rev_argc++] = NULL;
1780         rev_argv[rev_argc++] = "--left-right";
1781         rev_argv[rev_argc++] = symmetric;
1782         rev_argv[rev_argc++] = "--";
1783         rev_argv[rev_argc] = NULL;
1784
1785         strcpy(symmetric, sha1_to_hex(ours->object.sha1));
1786         strcpy(symmetric + 40, "...");
1787         strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
1788
1789         init_revisions(&revs, NULL);
1790         setup_revisions(rev_argc, rev_argv, &revs, NULL);
1791         prepare_revision_walk(&revs);
1792
1793         /* ... and count the commits on each side. */
1794         *num_ours = 0;
1795         *num_theirs = 0;
1796         while (1) {
1797                 struct commit *c = get_revision(&revs);
1798                 if (!c)
1799                         break;
1800                 if (c->object.flags & SYMMETRIC_LEFT)
1801                         (*num_ours)++;
1802                 else
1803                         (*num_theirs)++;
1804         }
1805
1806         /* clear object flags smudged by the above traversal */
1807         clear_commit_marks(ours, ALL_REV_FLAGS);
1808         clear_commit_marks(theirs, ALL_REV_FLAGS);
1809         return 1;
1810 }
1811
1812 /*
1813  * Return true when there is anything to report, otherwise false.
1814  */
1815 int format_tracking_info(struct branch *branch, struct strbuf *sb)
1816 {
1817         int ours, theirs;
1818         const char *base;
1819         int upstream_is_gone = 0;
1820
1821         switch (stat_tracking_info(branch, &ours, &theirs)) {
1822         case 0:
1823                 /* no base */
1824                 return 0;
1825         case -1:
1826                 /* with "gone" base */
1827                 upstream_is_gone = 1;
1828                 break;
1829         default:
1830                 /* with base */
1831                 break;
1832         }
1833
1834         base = branch->merge[0]->dst;
1835         base = shorten_unambiguous_ref(base, 0);
1836         if (upstream_is_gone) {
1837                 strbuf_addf(sb,
1838                         _("Your branch is based on '%s', but the upstream is gone.\n"),
1839                         base);
1840                 if (advice_status_hints)
1841                         strbuf_addf(sb,
1842                                 _("  (use \"git branch --unset-upstream\" to fixup)\n"));
1843         } else if (!ours && !theirs) {
1844                 strbuf_addf(sb,
1845                         _("Your branch is up-to-date with '%s'.\n"),
1846                         base);
1847         } else if (!theirs) {
1848                 strbuf_addf(sb,
1849                         Q_("Your branch is ahead of '%s' by %d commit.\n",
1850                            "Your branch is ahead of '%s' by %d commits.\n",
1851                            ours),
1852                         base, ours);
1853                 if (advice_status_hints)
1854                         strbuf_addf(sb,
1855                                 _("  (use \"git push\" to publish your local commits)\n"));
1856         } else if (!ours) {
1857                 strbuf_addf(sb,
1858                         Q_("Your branch is behind '%s' by %d commit, "
1859                                "and can be fast-forwarded.\n",
1860                            "Your branch is behind '%s' by %d commits, "
1861                                "and can be fast-forwarded.\n",
1862                            theirs),
1863                         base, theirs);
1864                 if (advice_status_hints)
1865                         strbuf_addf(sb,
1866                                 _("  (use \"git pull\" to update your local branch)\n"));
1867         } else {
1868                 strbuf_addf(sb,
1869                         Q_("Your branch and '%s' have diverged,\n"
1870                                "and have %d and %d different commit each, "
1871                                "respectively.\n",
1872                            "Your branch and '%s' have diverged,\n"
1873                                "and have %d and %d different commits each, "
1874                                "respectively.\n",
1875                            theirs),
1876                         base, ours, theirs);
1877                 if (advice_status_hints)
1878                         strbuf_addf(sb,
1879                                 _("  (use \"git pull\" to merge the remote branch into yours)\n"));
1880         }
1881         return 1;
1882 }
1883
1884 static int one_local_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
1885 {
1886         struct ref ***local_tail = cb_data;
1887         struct ref *ref;
1888         int len;
1889
1890         /* we already know it starts with refs/ to get here */
1891         if (check_refname_format(refname + 5, 0))
1892                 return 0;
1893
1894         len = strlen(refname) + 1;
1895         ref = xcalloc(1, sizeof(*ref) + len);
1896         hashcpy(ref->new_sha1, sha1);
1897         memcpy(ref->name, refname, len);
1898         **local_tail = ref;
1899         *local_tail = &ref->next;
1900         return 0;
1901 }
1902
1903 struct ref *get_local_heads(void)
1904 {
1905         struct ref *local_refs = NULL, **local_tail = &local_refs;
1906         for_each_ref(one_local_ref, &local_tail);
1907         return local_refs;
1908 }
1909
1910 struct ref *guess_remote_head(const struct ref *head,
1911                               const struct ref *refs,
1912                               int all)
1913 {
1914         const struct ref *r;
1915         struct ref *list = NULL;
1916         struct ref **tail = &list;
1917
1918         if (!head)
1919                 return NULL;
1920
1921         /*
1922          * Some transports support directly peeking at
1923          * where HEAD points; if that is the case, then
1924          * we don't have to guess.
1925          */
1926         if (head->symref)
1927                 return copy_ref(find_ref_by_name(refs, head->symref));
1928
1929         /* If refs/heads/master could be right, it is. */
1930         if (!all) {
1931                 r = find_ref_by_name(refs, "refs/heads/master");
1932                 if (r && !hashcmp(r->old_sha1, head->old_sha1))
1933                         return copy_ref(r);
1934         }
1935
1936         /* Look for another ref that points there */
1937         for (r = refs; r; r = r->next) {
1938                 if (r != head &&
1939                     !prefixcmp(r->name, "refs/heads/") &&
1940                     !hashcmp(r->old_sha1, head->old_sha1)) {
1941                         *tail = copy_ref(r);
1942                         tail = &((*tail)->next);
1943                         if (!all)
1944                                 break;
1945                 }
1946         }
1947
1948         return list;
1949 }
1950
1951 struct stale_heads_info {
1952         struct string_list *ref_names;
1953         struct ref **stale_refs_tail;
1954         struct refspec *refs;
1955         int ref_count;
1956 };
1957
1958 static int get_stale_heads_cb(const char *refname,
1959         const unsigned char *sha1, int flags, void *cb_data)
1960 {
1961         struct stale_heads_info *info = cb_data;
1962         struct refspec query;
1963         memset(&query, 0, sizeof(struct refspec));
1964         query.dst = (char *)refname;
1965
1966         if (query_refspecs(info->refs, info->ref_count, &query))
1967                 return 0; /* No matches */
1968
1969         /*
1970          * If we did find a suitable refspec and it's not a symref and
1971          * it's not in the list of refs that currently exist in that
1972          * remote we consider it to be stale.
1973          */
1974         if (!((flags & REF_ISSYMREF) ||
1975               string_list_has_string(info->ref_names, query.src))) {
1976                 struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
1977                 hashcpy(ref->new_sha1, sha1);
1978         }
1979
1980         free(query.src);
1981         return 0;
1982 }
1983
1984 struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fetch_map)
1985 {
1986         struct ref *ref, *stale_refs = NULL;
1987         struct string_list ref_names = STRING_LIST_INIT_NODUP;
1988         struct stale_heads_info info;
1989         info.ref_names = &ref_names;
1990         info.stale_refs_tail = &stale_refs;
1991         info.refs = refs;
1992         info.ref_count = ref_count;
1993         for (ref = fetch_map; ref; ref = ref->next)
1994                 string_list_append(&ref_names, ref->name);
1995         sort_string_list(&ref_names);
1996         for_each_ref(get_stale_heads_cb, &info);
1997         string_list_clear(&ref_names, 0);
1998         return stale_refs;
1999 }
2000
2001 /*
2002  * Compare-and-swap
2003  */
2004 void clear_cas_option(struct push_cas_option *cas)
2005 {
2006         int i;
2007
2008         for (i = 0; i < cas->nr; i++)
2009                 free(cas->entry[i].refname);
2010         free(cas->entry);
2011         memset(cas, 0, sizeof(*cas));
2012 }
2013
2014 static struct push_cas *add_cas_entry(struct push_cas_option *cas,
2015                                       const char *refname,
2016                                       size_t refnamelen)
2017 {
2018         struct push_cas *entry;
2019         ALLOC_GROW(cas->entry, cas->nr + 1, cas->alloc);
2020         entry = &cas->entry[cas->nr++];
2021         memset(entry, 0, sizeof(*entry));
2022         entry->refname = xmemdupz(refname, refnamelen);
2023         return entry;
2024 }
2025
2026 int parse_push_cas_option(struct push_cas_option *cas, const char *arg, int unset)
2027 {
2028         const char *colon;
2029         struct push_cas *entry;
2030
2031         if (unset) {
2032                 /* "--no-<option>" */
2033                 clear_cas_option(cas);
2034                 return 0;
2035         }
2036
2037         if (!arg) {
2038                 /* just "--<option>" */
2039                 cas->use_tracking_for_rest = 1;
2040                 return 0;
2041         }
2042
2043         /* "--<option>=refname" or "--<option>=refname:value" */
2044         colon = strchrnul(arg, ':');
2045         entry = add_cas_entry(cas, arg, colon - arg);
2046         if (!*colon)
2047                 entry->use_tracking = 1;
2048         else if (get_sha1(colon + 1, entry->expect))
2049                 return error("cannot parse expected object name '%s'", colon + 1);
2050         return 0;
2051 }
2052
2053 int parseopt_push_cas_option(const struct option *opt, const char *arg, int unset)
2054 {
2055         return parse_push_cas_option(opt->value, arg, unset);
2056 }
2057
2058 int is_empty_cas(const struct push_cas_option *cas)
2059 {
2060         return !cas->use_tracking_for_rest && !cas->nr;
2061 }
2062
2063 /*
2064  * Look at remote.fetch refspec and see if we have a remote
2065  * tracking branch for the refname there.  Fill its current
2066  * value in sha1[].
2067  * If we cannot do so, return negative to signal an error.
2068  */
2069 static int remote_tracking(struct remote *remote, const char *refname,
2070                            unsigned char sha1[20])
2071 {
2072         char *dst;
2073
2074         dst = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
2075         if (!dst)
2076                 return -1; /* no tracking ref for refname at remote */
2077         if (read_ref(dst, sha1))
2078                 return -1; /* we know what the tracking ref is but we cannot read it */
2079         return 0;
2080 }
2081
2082 static void apply_cas(struct push_cas_option *cas,
2083                       struct remote *remote,
2084                       struct ref *ref)
2085 {
2086         int i;
2087
2088         /* Find an explicit --<option>=<name>[:<value>] entry */
2089         for (i = 0; i < cas->nr; i++) {
2090                 struct push_cas *entry = &cas->entry[i];
2091                 if (!refname_match(entry->refname, ref->name, ref_rev_parse_rules))
2092                         continue;
2093                 ref->expect_old_sha1 = 1;
2094                 if (!entry->use_tracking)
2095                         hashcpy(ref->old_sha1_expect, cas->entry[i].expect);
2096                 else if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2097                         ref->expect_old_no_trackback = 1;
2098                 return;
2099         }
2100
2101         /* Are we using "--<option>" to cover all? */
2102         if (!cas->use_tracking_for_rest)
2103                 return;
2104
2105         ref->expect_old_sha1 = 1;
2106         if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2107                 ref->expect_old_no_trackback = 1;
2108 }
2109
2110 void apply_push_cas(struct push_cas_option *cas,
2111                     struct remote *remote,
2112                     struct ref *remote_refs)
2113 {
2114         struct ref *ref;
2115         for (ref = remote_refs; ref; ref = ref->next)
2116                 apply_cas(cas, remote, ref);
2117 }