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 static struct hashmap remotes_hash;
  46
  47 static struct branch **branches;
  48 static int branches_alloc;
  49 static int branches_nr;
  50
  51 static struct branch *current_branch;
  52 static const char *default_remote_name;
  53 static const char *branch_pushremote_name;
  54 static const char *pushremote_name;
  55 static int explicit_default_remote_name;
  56
  57 static struct rewrites rewrites;
  58 static struct rewrites rewrites_push;
  59
  60 #define BUF_SIZE (2048)
  61 static char buffer[BUF_SIZE];
  62
  63 static int valid_remote(const struct remote *remote)
  64 {
  65         return (!!remote->url) || (!!remote->foreign_vcs);
  66 }
  67
  68 static const char *alias_url(const char *url, struct rewrites *r)
  69 {
  70         int i, j;
  71         char *ret;
  72         struct counted_string *longest;
  73         int longest_i;
  74
  75         longest = NULL;
  76         longest_i = -1;
  77         for (i = 0; i < r->rewrite_nr; i++) {
  78                 if (!r->rewrite[i])
  79                         continue;
  80                 for (j = 0; j < r->rewrite[i]->instead_of_nr; j++) {
  81                         if (starts_with(url, r->rewrite[i]->instead_of[j].s) &&
  82                             (!longest ||
  83                              longest->len < r->rewrite[i]->instead_of[j].len)) {
  84                                 longest = &(r->rewrite[i]->instead_of[j]);
  85                                 longest_i = i;
  86                         }
  87                 }
  88         }
  89         if (!longest)
  90                 return url;
  91
  92         ret = xmalloc(r->rewrite[longest_i]->baselen +
  93                      (strlen(url) - longest->len) + 1);
  94         strcpy(ret, r->rewrite[longest_i]->base);
  95         strcpy(ret + r->rewrite[longest_i]->baselen, url + longest->len);
  96         return ret;
  97 }
  98
  99 static void add_push_refspec(struct remote *remote, const char *ref)
 100 {
 101         ALLOC_GROW(remote->push_refspec,
 102                    remote->push_refspec_nr + 1,
 103                    remote->push_refspec_alloc);
 104         remote->push_refspec[remote->push_refspec_nr++] = ref;
 105 }
 106
 107 static void add_fetch_refspec(struct remote *remote, const char *ref)
 108 {
 109         ALLOC_GROW(remote->fetch_refspec,
 110                    remote->fetch_refspec_nr + 1,
 111                    remote->fetch_refspec_alloc);
 112         remote->fetch_refspec[remote->fetch_refspec_nr++] = ref;
 113 }
 114
 115 static void add_url(struct remote *remote, const char *url)
 116 {
 117         ALLOC_GROW(remote->url, remote->url_nr + 1, remote->url_alloc);
 118         remote->url[remote->url_nr++] = url;
 119 }
 120
 121 static void add_pushurl(struct remote *remote, const char *pushurl)
 122 {
 123         ALLOC_GROW(remote->pushurl, remote->pushurl_nr + 1, remote->pushurl_alloc);
 124         remote->pushurl[remote->pushurl_nr++] = pushurl;
 125 }
 126
 127 static void add_pushurl_alias(struct remote *remote, const char *url)
 128 {
 129         const char *pushurl = alias_url(url, &rewrites_push);
 130         if (pushurl != url)
 131                 add_pushurl(remote, pushurl);
 132 }
 133
 134 static void add_url_alias(struct remote *remote, const char *url)
 135 {
 136         add_url(remote, alias_url(url, &rewrites));
 137         add_pushurl_alias(remote, url);
 138 }
 139
 140 struct remotes_hash_key {
 141         const char *str;
 142         int len;
 143 };
 144
 145 static int remotes_hash_cmp(const struct remote *a, const struct remote *b, const struct remotes_hash_key *key)
 146 {
 147         if (key)
 148                 return strncmp(a->name, key->str, key->len) || a->name[key->len];
 149         else
 150                 return strcmp(a->name, b->name);
 151 }
 152
 153 static inline void init_remotes_hash(void)
 154 {
 155         if (!remotes_hash.cmpfn)
 156                 hashmap_init(&remotes_hash, (hashmap_cmp_fn)remotes_hash_cmp, 0);
 157 }
 158
 159 static struct remote *make_remote(const char *name, int len)
 160 {
 161         struct remote *ret, *replaced;
 162         struct remotes_hash_key lookup;
 163         struct hashmap_entry lookup_entry;
 164
 165         if (!len)
 166                 len = strlen(name);
 167
 168         init_remotes_hash();
 169         lookup.str = name;
 170         lookup.len = len;
 171         hashmap_entry_init(&lookup_entry, memhash(name, len));
 172
 173         if ((ret = hashmap_get(&remotes_hash, &lookup_entry, &lookup)) != NULL)
 174                 return ret;
 175
 176         ret = xcalloc(1, sizeof(struct remote));
 177         ret->prune = -1;  /* unspecified */
 178         ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 179         remotes[remotes_nr++] = ret;
 180         ret->name = xstrndup(name, len);
 181
 182         hashmap_entry_init(ret, lookup_entry.hash);
 183         replaced = hashmap_put(&remotes_hash, ret);
 184         assert(replaced == NULL);  /* no previous entry overwritten */
 185         return ret;
 186 }
 187
 188 static void add_merge(struct branch *branch, const char *name)
 189 {
 190         ALLOC_GROW(branch->merge_name, branch->merge_nr + 1,
 191                    branch->merge_alloc);
 192         branch->merge_name[branch->merge_nr++] = name;
 193 }
 194
 195 static struct branch *make_branch(const char *name, int len)
 196 {
 197         struct branch *ret;
 198         int i;
 199
 200         for (i = 0; i < branches_nr; i++) {
 201                 if (len ? (!strncmp(name, branches[i]->name, len) &&
 202                            !branches[i]->name[len]) :
 203                     !strcmp(name, branches[i]->name))
 204                         return branches[i];
 205         }
 206
 207         ALLOC_GROW(branches, branches_nr + 1, branches_alloc);
 208         ret = xcalloc(1, sizeof(struct branch));
 209         branches[branches_nr++] = ret;
 210         if (len)
 211                 ret->name = xstrndup(name, len);
 212         else
 213                 ret->name = xstrdup(name);
 214         ret->refname = xstrfmt("refs/heads/%s", ret->name);
 215
 216         return ret;
 217 }
 218
 219 static struct rewrite *make_rewrite(struct rewrites *r, const char *base, int len)
 220 {
 221         struct rewrite *ret;
 222         int i;
 223
 224         for (i = 0; i < r->rewrite_nr; i++) {
 225                 if (len
 226                     ? (len == r->rewrite[i]->baselen &&
 227                        !strncmp(base, r->rewrite[i]->base, len))
 228                     : !strcmp(base, r->rewrite[i]->base))
 229                         return r->rewrite[i];
 230         }
 231
 232         ALLOC_GROW(r->rewrite, r->rewrite_nr + 1, r->rewrite_alloc);
 233         ret = xcalloc(1, sizeof(struct rewrite));
 234         r->rewrite[r->rewrite_nr++] = ret;
 235         if (len) {
 236                 ret->base = xstrndup(base, len);
 237                 ret->baselen = len;
 238         }
 239         else {
 240                 ret->base = xstrdup(base);
 241                 ret->baselen = strlen(base);
 242         }
 243         return ret;
 244 }
 245
 246 static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
 247 {
 248         ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
 249         rewrite->instead_of[rewrite->instead_of_nr].s = instead_of;
 250         rewrite->instead_of[rewrite->instead_of_nr].len = strlen(instead_of);
 251         rewrite->instead_of_nr++;
 252 }
 253
 254 static void read_remotes_file(struct remote *remote)
 255 {
 256         FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
 257
 258         if (!f)
 259                 return;
 260         remote->origin = REMOTE_REMOTES;
 261         while (fgets(buffer, BUF_SIZE, f)) {
 262                 int value_list;
 263                 char *s, *p;
 264
 265                 if (starts_with(buffer, "URL:")) {
 266                         value_list = 0;
 267                         s = buffer + 4;
 268                 } else if (starts_with(buffer, "Push:")) {
 269                         value_list = 1;
 270                         s = buffer + 5;
 271                 } else if (starts_with(buffer, "Pull:")) {
 272                         value_list = 2;
 273                         s = buffer + 5;
 274                 } else
 275                         continue;
 276
 277                 while (isspace(*s))
 278                         s++;
 279                 if (!*s)
 280                         continue;
 281
 282                 p = s + strlen(s);
 283                 while (isspace(p[-1]))
 284                         *--p = 0;
 285
 286                 switch (value_list) {
 287                 case 0:
 288                         add_url_alias(remote, xstrdup(s));
 289                         break;
 290                 case 1:
 291                         add_push_refspec(remote, xstrdup(s));
 292                         break;
 293                 case 2:
 294                         add_fetch_refspec(remote, xstrdup(s));
 295                         break;
 296                 }
 297         }
 298         fclose(f);
 299 }
 300
 301 static void read_branches_file(struct remote *remote)
 302 {
 303         char *frag;
 304         struct strbuf branch = STRBUF_INIT;
 305         int n = 1000;
 306         FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 307         char *s, *p;
 308         int len;
 309
 310         if (!f)
 311                 return;
 312         s = fgets(buffer, BUF_SIZE, f);
 313         fclose(f);
 314         if (!s)
 315                 return;
 316         while (isspace(*s))
 317                 s++;
 318         if (!*s)
 319                 return;
 320         remote->origin = REMOTE_BRANCHES;
 321         p = s + strlen(s);
 322         while (isspace(p[-1]))
 323                 *--p = 0;
 324         len = p - s;
 325         p = xmalloc(len + 1);
 326         strcpy(p, s);
 327
 328         /*
 329          * The branches file would have URL and optionally
 330          * #branch specified.  The "master" (or specified) branch is
 331          * fetched and stored in the local branch of the same name.
 332          */
 333         frag = strchr(p, '#');
 334         if (frag) {
 335                 *(frag++) = '\0';
 336                 strbuf_addf(&branch, "refs/heads/%s", frag);
 337         } else
 338                 strbuf_addstr(&branch, "refs/heads/master");
 339
 340         strbuf_addf(&branch, ":refs/heads/%s", remote->name);
 341         add_url_alias(remote, p);
 342         add_fetch_refspec(remote, strbuf_detach(&branch, NULL));
 343         /*
 344          * Cogito compatible push: push current HEAD to remote #branch
 345          * (master if missing)
 346          */
 347         strbuf_init(&branch, 0);
 348         strbuf_addstr(&branch, "HEAD");
 349         if (frag)
 350                 strbuf_addf(&branch, ":refs/heads/%s", frag);
 351         else
 352                 strbuf_addstr(&branch, ":refs/heads/master");
 353         add_push_refspec(remote, strbuf_detach(&branch, NULL));
 354         remote->fetch_tags = 1; /* always auto-follow */
 355 }
 356
 357 static int handle_config(const char *key, const char *value, void *cb)
 358 {
 359         const char *name;
 360         const char *subkey;
 361         struct remote *remote;
 362         struct branch *branch;
 363         if (starts_with(key, "branch.")) {
 364                 name = key + 7;
 365                 subkey = strrchr(name, '.');
 366                 if (!subkey)
 367                         return 0;
 368                 branch = make_branch(name, subkey - name);
 369                 if (!strcmp(subkey, ".remote")) {
 370                         if (git_config_string(&branch->remote_name, key, value))
 371                                 return -1;
 372                         if (branch == current_branch) {
 373                                 default_remote_name = branch->remote_name;
 374                                 explicit_default_remote_name = 1;
 375                         }
 376                 } else if (!strcmp(subkey, ".pushremote")) {
 377                         if (git_config_string(&branch->pushremote_name, key, value))
 378                                 return -1;
 379                         if (branch == current_branch)
 380                                 branch_pushremote_name = xstrdup(branch->pushremote_name);
 381                 } else if (!strcmp(subkey, ".merge")) {
 382                         if (!value)
 383                                 return config_error_nonbool(key);
 384                         add_merge(branch, xstrdup(value));
 385                 } else if (!strcmp(subkey, ".push")) {
 386                         if (git_config_string(&branch->push_name, key, value))
 387                                 return -1;
 388                 }
 389                 return 0;
 390         }
 391         if (starts_with(key, "url.")) {
 392                 struct rewrite *rewrite;
 393                 name = key + 4;
 394                 subkey = strrchr(name, '.');
 395                 if (!subkey)
 396                         return 0;
 397                 if (!strcmp(subkey, ".insteadof")) {
 398                         rewrite = make_rewrite(&rewrites, name, subkey - name);
 399                         if (!value)
 400                                 return config_error_nonbool(key);
 401                         add_instead_of(rewrite, xstrdup(value));
 402                 } else if (!strcmp(subkey, ".pushinsteadof")) {
 403                         rewrite = make_rewrite(&rewrites_push, name, subkey - name);
 404                         if (!value)
 405                                 return config_error_nonbool(key);
 406                         add_instead_of(rewrite, xstrdup(value));
 407                 }
 408         }
 409
 410         if (!starts_with(key,  "remote."))
 411                 return 0;
 412         name = key + 7;
 413
 414         /* Handle remote.* variables */
 415         if (!strcmp(name, "pushdefault"))
 416                 return git_config_string(&pushremote_name, key, value);
 417
 418         /* Handle remote.<name>.* variables */
 419         if (*name == '/') {
 420                 warning("Config remote shorthand cannot begin with '/': %s",
 421                         name);
 422                 return 0;
 423         }
 424         subkey = strrchr(name, '.');
 425         if (!subkey)
 426                 return 0;
 427         remote = make_remote(name, subkey - name);
 428         remote->origin = REMOTE_CONFIG;
 429         if (!strcmp(subkey, ".mirror"))
 430                 remote->mirror = git_config_bool(key, value);
 431         else if (!strcmp(subkey, ".skipdefaultupdate"))
 432                 remote->skip_default_update = git_config_bool(key, value);
 433         else if (!strcmp(subkey, ".skipfetchall"))
 434                 remote->skip_default_update = git_config_bool(key, value);
 435         else if (!strcmp(subkey, ".prune"))
 436                 remote->prune = git_config_bool(key, value);
 437         else if (!strcmp(subkey, ".url")) {
 438                 const char *v;
 439                 if (git_config_string(&v, key, value))
 440                         return -1;
 441                 add_url(remote, v);
 442         } else if (!strcmp(subkey, ".pushurl")) {
 443                 const char *v;
 444                 if (git_config_string(&v, key, value))
 445                         return -1;
 446                 add_pushurl(remote, v);
 447         } else if (!strcmp(subkey, ".push")) {
 448                 const char *v;
 449                 if (git_config_string(&v, key, value))
 450                         return -1;
 451                 add_push_refspec(remote, v);
 452         } else if (!strcmp(subkey, ".fetch")) {
 453                 const char *v;
 454                 if (git_config_string(&v, key, value))
 455                         return -1;
 456                 add_fetch_refspec(remote, v);
 457         } else if (!strcmp(subkey, ".receivepack")) {
 458                 const char *v;
 459                 if (git_config_string(&v, key, value))
 460                         return -1;
 461                 if (!remote->receivepack)
 462                         remote->receivepack = v;
 463                 else
 464                         error("more than one receivepack given, using the first");
 465         } else if (!strcmp(subkey, ".uploadpack")) {
 466                 const char *v;
 467                 if (git_config_string(&v, key, value))
 468                         return -1;
 469                 if (!remote->uploadpack)
 470                         remote->uploadpack = v;
 471                 else
 472                         error("more than one uploadpack given, using the first");
 473         } else if (!strcmp(subkey, ".tagopt")) {
 474                 if (!strcmp(value, "--no-tags"))
 475                         remote->fetch_tags = -1;
 476                 else if (!strcmp(value, "--tags"))
 477                         remote->fetch_tags = 2;
 478         } else if (!strcmp(subkey, ".proxy")) {
 479                 return git_config_string((const char **)&remote->http_proxy,
 480                                          key, value);
 481         } else if (!strcmp(subkey, ".vcs")) {
 482                 return git_config_string(&remote->foreign_vcs, key, value);
 483         }
 484         return 0;
 485 }
 486
 487 static void alias_all_urls(void)
 488 {
 489         int i, j;
 490         for (i = 0; i < remotes_nr; i++) {
 491                 int add_pushurl_aliases;
 492                 if (!remotes[i])
 493                         continue;
 494                 for (j = 0; j < remotes[i]->pushurl_nr; j++) {
 495                         remotes[i]->pushurl[j] = alias_url(remotes[i]->pushurl[j], &rewrites);
 496                 }
 497                 add_pushurl_aliases = remotes[i]->pushurl_nr == 0;
 498                 for (j = 0; j < remotes[i]->url_nr; j++) {
 499                         if (add_pushurl_aliases)
 500                                 add_pushurl_alias(remotes[i], remotes[i]->url[j]);
 501                         remotes[i]->url[j] = alias_url(remotes[i]->url[j], &rewrites);
 502                 }
 503         }
 504 }
 505
 506 static void read_config(void)
 507 {
 508         unsigned char sha1[20];
 509         const char *head_ref;
 510         int flag;
 511         if (default_remote_name) /* did this already */
 512                 return;
 513         default_remote_name = "origin";
 514         current_branch = NULL;
 515         head_ref = resolve_ref_unsafe("HEAD", 0, sha1, &flag);
 516         if (head_ref && (flag & REF_ISSYMREF) &&
 517             skip_prefix(head_ref, "refs/heads/", &head_ref)) {
 518                 current_branch = make_branch(head_ref, 0);
 519         }
 520         git_config(handle_config, NULL);
 521         if (branch_pushremote_name) {
 522                 free((char *)pushremote_name);
 523                 pushremote_name = branch_pushremote_name;
 524         }
 525         alias_all_urls();
 526 }
 527
 528 /*
 529  * This function frees a refspec array.
 530  * Warning: code paths should be checked to ensure that the src
 531  *          and dst pointers are always freeable pointers as well
 532  *          as the refspec pointer itself.
 533  */
 534 static void free_refspecs(struct refspec *refspec, int nr_refspec)
 535 {
 536         int i;
 537
 538         if (!refspec)
 539                 return;
 540
 541         for (i = 0; i < nr_refspec; i++) {
 542                 free(refspec[i].src);
 543                 free(refspec[i].dst);
 544         }
 545         free(refspec);
 546 }
 547
 548 static struct refspec *parse_refspec_internal(int nr_refspec, const char **refspec, int fetch, int verify)
 549 {
 550         int i;
 551         struct refspec *rs = xcalloc(nr_refspec, sizeof(*rs));
 552
 553         for (i = 0; i < nr_refspec; i++) {
 554                 size_t llen;
 555                 int is_glob;
 556                 const char *lhs, *rhs;
 557                 int flags;
 558
 559                 is_glob = 0;
 560
 561                 lhs = refspec[i];
 562                 if (*lhs == '+') {
 563                         rs[i].force = 1;
 564                         lhs++;
 565                 }
 566
 567                 rhs = strrchr(lhs, ':');
 568
 569                 /*
 570                  * Before going on, special case ":" (or "+:") as a refspec
 571                  * for pushing matching refs.
 572                  */
 573                 if (!fetch && rhs == lhs && rhs[1] == '\0') {
 574                         rs[i].matching = 1;
 575                         continue;
 576                 }
 577
 578                 if (rhs) {
 579                         size_t rlen = strlen(++rhs);
 580                         is_glob = (1 <= rlen && strchr(rhs, '*'));
 581                         rs[i].dst = xstrndup(rhs, rlen);
 582                 }
 583
 584                 llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 585                 if (1 <= llen && memchr(lhs, '*', llen)) {
 586                         if ((rhs && !is_glob) || (!rhs && fetch))
 587                                 goto invalid;
 588                         is_glob = 1;
 589                 } else if (rhs && is_glob) {
 590                         goto invalid;
 591                 }
 592
 593                 rs[i].pattern = is_glob;
 594                 rs[i].src = xstrndup(lhs, llen);
 595                 flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 596
 597                 if (fetch) {
 598                         unsigned char unused[40];
 599
 600                         /* LHS */
 601                         if (!*rs[i].src)
 602                                 ; /* empty is ok; it means "HEAD" */
 603                         else if (llen == 40 && !get_sha1_hex(rs[i].src, unused))
 604                                 rs[i].exact_sha1 = 1; /* ok */
 605                         else if (!check_refname_format(rs[i].src, flags))
 606                                 ; /* valid looking ref is ok */
 607                         else
 608                                 goto invalid;
 609                         /* RHS */
 610                         if (!rs[i].dst)
 611                                 ; /* missing is ok; it is the same as empty */
 612                         else if (!*rs[i].dst)
 613                                 ; /* empty is ok; it means "do not store" */
 614                         else if (!check_refname_format(rs[i].dst, flags))
 615                                 ; /* valid looking ref is ok */
 616                         else
 617                                 goto invalid;
 618                 } else {
 619                         /*
 620                          * LHS
 621                          * - empty is allowed; it means delete.
 622                          * - when wildcarded, it must be a valid looking ref.
 623                          * - otherwise, it must be an extended SHA-1, but
 624                          *   there is no existing way to validate this.
 625                          */
 626                         if (!*rs[i].src)
 627                                 ; /* empty is ok */
 628                         else if (is_glob) {
 629                                 if (check_refname_format(rs[i].src, flags))
 630                                         goto invalid;
 631                         }
 632                         else
 633                                 ; /* anything goes, for now */
 634                         /*
 635                          * RHS
 636                          * - missing is allowed, but LHS then must be a
 637                          *   valid looking ref.
 638                          * - empty is not allowed.
 639                          * - otherwise it must be a valid looking ref.
 640                          */
 641                         if (!rs[i].dst) {
 642                                 if (check_refname_format(rs[i].src, flags))
 643                                         goto invalid;
 644                         } else if (!*rs[i].dst) {
 645                                 goto invalid;
 646                         } else {
 647                                 if (check_refname_format(rs[i].dst, flags))
 648                                         goto invalid;
 649                         }
 650                 }
 651         }
 652         return rs;
 653
 654  invalid:
 655         if (verify) {
 656                 /*
 657                  * nr_refspec must be greater than zero and i must be valid
 658                  * since it is only possible to reach this point from within
 659                  * the for loop above.
 660                  */
 661                 free_refspecs(rs, i+1);
 662                 return NULL;
 663         }
 664         die("Invalid refspec '%s'", refspec[i]);
 665 }
 666
 667 int valid_fetch_refspec(const char *fetch_refspec_str)
 668 {
 669         struct refspec *refspec;
 670
 671         refspec = parse_refspec_internal(1, &fetch_refspec_str, 1, 1);
 672         free_refspecs(refspec, 1);
 673         return !!refspec;
 674 }
 675
 676 struct refspec *parse_fetch_refspec(int nr_refspec, const char **refspec)
 677 {
 678         return parse_refspec_internal(nr_refspec, refspec, 1, 0);
 679 }
 680
 681 static struct refspec *parse_push_refspec(int nr_refspec, const char **refspec)
 682 {
 683         return parse_refspec_internal(nr_refspec, refspec, 0, 0);
 684 }
 685
 686 void free_refspec(int nr_refspec, struct refspec *refspec)
 687 {
 688         int i;
 689         for (i = 0; i < nr_refspec; i++) {
 690                 free(refspec[i].src);
 691                 free(refspec[i].dst);
 692         }
 693         free(refspec);
 694 }
 695
 696 static int valid_remote_nick(const char *name)
 697 {
 698         if (!name[0] || is_dot_or_dotdot(name))
 699                 return 0;
 700         return !strchr(name, '/'); /* no slash */
 701 }
 702
 703 static struct remote *remote_get_1(const char *name, const char *pushremote_name)
 704 {
 705         struct remote *ret;
 706         int name_given = 0;
 707
 708         if (name)
 709                 name_given = 1;
 710         else {
 711                 if (pushremote_name) {
 712                         name = pushremote_name;
 713                         name_given = 1;
 714                 } else {
 715                         name = default_remote_name;
 716                         name_given = explicit_default_remote_name;
 717                 }
 718         }
 719
 720         ret = make_remote(name, 0);
 721         if (valid_remote_nick(name)) {
 722                 if (!valid_remote(ret))
 723                         read_remotes_file(ret);
 724                 if (!valid_remote(ret))
 725                         read_branches_file(ret);
 726         }
 727         if (name_given && !valid_remote(ret))
 728                 add_url_alias(ret, name);
 729         if (!valid_remote(ret))
 730                 return NULL;
 731         ret->fetch = parse_fetch_refspec(ret->fetch_refspec_nr, ret->fetch_refspec);
 732         ret->push = parse_push_refspec(ret->push_refspec_nr, ret->push_refspec);
 733         return ret;
 734 }
 735
 736 struct remote *remote_get(const char *name)
 737 {
 738         read_config();
 739         return remote_get_1(name, NULL);
 740 }
 741
 742 struct remote *pushremote_get(const char *name)
 743 {
 744         read_config();
 745         return remote_get_1(name, pushremote_name);
 746 }
 747
 748 int remote_is_configured(const char *name)
 749 {
 750         struct remotes_hash_key lookup;
 751         struct hashmap_entry lookup_entry;
 752         read_config();
 753
 754         init_remotes_hash();
 755         lookup.str = name;
 756         lookup.len = strlen(name);
 757         hashmap_entry_init(&lookup_entry, memhash(name, lookup.len));
 758
 759         return hashmap_get(&remotes_hash, &lookup_entry, &lookup) != NULL;
 760 }
 761
 762 int for_each_remote(each_remote_fn fn, void *priv)
 763 {
 764         int i, result = 0;
 765         read_config();
 766         for (i = 0; i < remotes_nr && !result; i++) {
 767                 struct remote *r = remotes[i];
 768                 if (!r)
 769                         continue;
 770                 if (!r->fetch)
 771                         r->fetch = parse_fetch_refspec(r->fetch_refspec_nr,
 772                                                        r->fetch_refspec);
 773                 if (!r->push)
 774                         r->push = parse_push_refspec(r->push_refspec_nr,
 775                                                      r->push_refspec);
 776                 result = fn(r, priv);
 777         }
 778         return result;
 779 }
 780
 781 static void handle_duplicate(struct ref *ref1, struct ref *ref2)
 782 {
 783         if (strcmp(ref1->name, ref2->name)) {
 784                 if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 785                     ref2->fetch_head_status != FETCH_HEAD_IGNORE) {
 786                         die(_("Cannot fetch both %s and %s to %s"),
 787                             ref1->name, ref2->name, ref2->peer_ref->name);
 788                 } else if (ref1->fetch_head_status != FETCH_HEAD_IGNORE &&
 789                            ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 790                         warning(_("%s usually tracks %s, not %s"),
 791                                 ref2->peer_ref->name, ref2->name, ref1->name);
 792                 } else if (ref1->fetch_head_status == FETCH_HEAD_IGNORE &&
 793                            ref2->fetch_head_status == FETCH_HEAD_IGNORE) {
 794                         die(_("%s tracks both %s and %s"),
 795                             ref2->peer_ref->name, ref1->name, ref2->name);
 796                 } else {
 797                         /*
 798                          * This last possibility doesn't occur because
 799                          * FETCH_HEAD_IGNORE entries always appear at
 800                          * the end of the list.
 801                          */
 802                         die(_("Internal error"));
 803                 }
 804         }
 805         free(ref2->peer_ref);
 806         free(ref2);
 807 }
 808
 809 struct ref *ref_remove_duplicates(struct ref *ref_map)
 810 {
 811         struct string_list refs = STRING_LIST_INIT_NODUP;
 812         struct ref *retval = NULL;
 813         struct ref **p = &retval;
 814
 815         while (ref_map) {
 816                 struct ref *ref = ref_map;
 817
 818                 ref_map = ref_map->next;
 819                 ref->next = NULL;
 820
 821                 if (!ref->peer_ref) {
 822                         *p = ref;
 823                         p = &ref->next;
 824                 } else {
 825                         struct string_list_item *item =
 826                                 string_list_insert(&refs, ref->peer_ref->name);
 827
 828                         if (item->util) {
 829                                 /* Entry already existed */
 830                                 handle_duplicate((struct ref *)item->util, ref);
 831                         } else {
 832                                 *p = ref;
 833                                 p = &ref->next;
 834                                 item->util = ref;
 835                         }
 836                 }
 837         }
 838
 839         string_list_clear(&refs, 0);
 840         return retval;
 841 }
 842
 843 int remote_has_url(struct remote *remote, const char *url)
 844 {
 845         int i;
 846         for (i = 0; i < remote->url_nr; i++) {
 847                 if (!strcmp(remote->url[i], url))
 848                         return 1;
 849         }
 850         return 0;
 851 }
 852
 853 static int match_name_with_pattern(const char *key, const char *name,
 854                                    const char *value, char **result)
 855 {
 856         const char *kstar = strchr(key, '*');
 857         size_t klen;
 858         size_t ksuffixlen;
 859         size_t namelen;
 860         int ret;
 861         if (!kstar)
 862                 die("Key '%s' of pattern had no '*'", key);
 863         klen = kstar - key;
 864         ksuffixlen = strlen(kstar + 1);
 865         namelen = strlen(name);
 866         ret = !strncmp(name, key, klen) && namelen >= klen + ksuffixlen &&
 867                 !memcmp(name + namelen - ksuffixlen, kstar + 1, ksuffixlen);
 868         if (ret && value) {
 869                 struct strbuf sb = STRBUF_INIT;
 870                 const char *vstar = strchr(value, '*');
 871                 if (!vstar)
 872                         die("Value '%s' of pattern has no '*'", value);
 873                 strbuf_add(&sb, value, vstar - value);
 874                 strbuf_add(&sb, name + klen, namelen - klen - ksuffixlen);
 875                 strbuf_addstr(&sb, vstar + 1);
 876                 *result = strbuf_detach(&sb, NULL);
 877         }
 878         return ret;
 879 }
 880
 881 static void query_refspecs_multiple(struct refspec *refs, int ref_count, struct refspec *query, struct string_list *results)
 882 {
 883         int i;
 884         int find_src = !query->src;
 885
 886         if (find_src && !query->dst)
 887                 error("query_refspecs_multiple: need either src or dst");
 888
 889         for (i = 0; i < ref_count; i++) {
 890                 struct refspec *refspec = &refs[i];
 891                 const char *key = find_src ? refspec->dst : refspec->src;
 892                 const char *value = find_src ? refspec->src : refspec->dst;
 893                 const char *needle = find_src ? query->dst : query->src;
 894                 char **result = find_src ? &query->src : &query->dst;
 895
 896                 if (!refspec->dst)
 897                         continue;
 898                 if (refspec->pattern) {
 899                         if (match_name_with_pattern(key, needle, value, result))
 900                                 string_list_append_nodup(results, *result);
 901                 } else if (!strcmp(needle, key)) {
 902                         string_list_append(results, value);
 903                 }
 904         }
 905 }
 906
 907 int query_refspecs(struct refspec *refs, int ref_count, struct refspec *query)
 908 {
 909         int i;
 910         int find_src = !query->src;
 911         const char *needle = find_src ? query->dst : query->src;
 912         char **result = find_src ? &query->src : &query->dst;
 913
 914         if (find_src && !query->dst)
 915                 return error("query_refspecs: need either src or dst");
 916
 917         for (i = 0; i < ref_count; i++) {
 918                 struct refspec *refspec = &refs[i];
 919                 const char *key = find_src ? refspec->dst : refspec->src;
 920                 const char *value = find_src ? refspec->src : refspec->dst;
 921
 922                 if (!refspec->dst)
 923                         continue;
 924                 if (refspec->pattern) {
 925                         if (match_name_with_pattern(key, needle, value, result)) {
 926                                 query->force = refspec->force;
 927                                 return 0;
 928                         }
 929                 } else if (!strcmp(needle, key)) {
 930                         *result = xstrdup(value);
 931                         query->force = refspec->force;
 932                         return 0;
 933                 }
 934         }
 935         return -1;
 936 }
 937
 938 char *apply_refspecs(struct refspec *refspecs, int nr_refspec,
 939                      const char *name)
 940 {
 941         struct refspec query;
 942
 943         memset(&query, 0, sizeof(struct refspec));
 944         query.src = (char *)name;
 945
 946         if (query_refspecs(refspecs, nr_refspec, &query))
 947                 return NULL;
 948
 949         return query.dst;
 950 }
 951
 952 int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 953 {
 954         return query_refspecs(remote->fetch, remote->fetch_refspec_nr, refspec);
 955 }
 956
 957 static struct ref *alloc_ref_with_prefix(const char *prefix, size_t prefixlen,
 958                 const char *name)
 959 {
 960         size_t len = strlen(name);
 961         struct ref *ref = xcalloc(1, sizeof(struct ref) + prefixlen + len + 1);
 962         memcpy(ref->name, prefix, prefixlen);
 963         memcpy(ref->name + prefixlen, name, len);
 964         return ref;
 965 }
 966
 967 struct ref *alloc_ref(const char *name)
 968 {
 969         return alloc_ref_with_prefix("", 0, name);
 970 }
 971
 972 struct ref *copy_ref(const struct ref *ref)
 973 {
 974         struct ref *cpy;
 975         size_t len;
 976         if (!ref)
 977                 return NULL;
 978         len = strlen(ref->name);
 979         cpy = xmalloc(sizeof(struct ref) + len + 1);
 980         memcpy(cpy, ref, sizeof(struct ref) + len + 1);
 981         cpy->next = NULL;
 982         cpy->symref = ref->symref ? xstrdup(ref->symref) : NULL;
 983         cpy->remote_status = ref->remote_status ? xstrdup(ref->remote_status) : NULL;
 984         cpy->peer_ref = copy_ref(ref->peer_ref);
 985         return cpy;
 986 }
 987
 988 struct ref *copy_ref_list(const struct ref *ref)
 989 {
 990         struct ref *ret = NULL;
 991         struct ref **tail = &ret;
 992         while (ref) {
 993                 *tail = copy_ref(ref);
 994                 ref = ref->next;
 995                 tail = &((*tail)->next);
 996         }
 997         return ret;
 998 }
 999
1000 static void free_ref(struct ref *ref)
1001 {
1002         if (!ref)
1003                 return;
1004         free_ref(ref->peer_ref);
1005         free(ref->remote_status);
1006         free(ref->symref);
1007         free(ref);
1008 }
1009
1010 void free_refs(struct ref *ref)
1011 {
1012         struct ref *next;
1013         while (ref) {
1014                 next = ref->next;
1015                 free_ref(ref);
1016                 ref = next;
1017         }
1018 }
1019
1020 int ref_compare_name(const void *va, const void *vb)
1021 {
1022         const struct ref *a = va, *b = vb;
1023         return strcmp(a->name, b->name);
1024 }
1025
1026 static void *ref_list_get_next(const void *a)
1027 {
1028         return ((const struct ref *)a)->next;
1029 }
1030
1031 static void ref_list_set_next(void *a, void *next)
1032 {
1033         ((struct ref *)a)->next = next;
1034 }
1035
1036 void sort_ref_list(struct ref **l, int (*cmp)(const void *, const void *))
1037 {
1038         *l = llist_mergesort(*l, ref_list_get_next, ref_list_set_next, cmp);
1039 }
1040
1041 int count_refspec_match(const char *pattern,
1042                         struct ref *refs,
1043                         struct ref **matched_ref)
1044 {
1045         int patlen = strlen(pattern);
1046         struct ref *matched_weak = NULL;
1047         struct ref *matched = NULL;
1048         int weak_match = 0;
1049         int match = 0;
1050
1051         for (weak_match = match = 0; refs; refs = refs->next) {
1052                 char *name = refs->name;
1053                 int namelen = strlen(name);
1054
1055                 if (!refname_match(pattern, name))
1056                         continue;
1057
1058                 /* A match is "weak" if it is with refs outside
1059                  * heads or tags, and did not specify the pattern
1060                  * in full (e.g. "refs/remotes/origin/master") or at
1061                  * least from the toplevel (e.g. "remotes/origin/master");
1062                  * otherwise "git push $URL master" would result in
1063                  * ambiguity between remotes/origin/master and heads/master
1064                  * at the remote site.
1065                  */
1066                 if (namelen != patlen &&
1067                     patlen != namelen - 5 &&
1068                     !starts_with(name, "refs/heads/") &&
1069                     !starts_with(name, "refs/tags/")) {
1070                         /* We want to catch the case where only weak
1071                          * matches are found and there are multiple
1072                          * matches, and where more than one strong
1073                          * matches are found, as ambiguous.  One
1074                          * strong match with zero or more weak matches
1075                          * are acceptable as a unique match.
1076                          */
1077                         matched_weak = refs;
1078                         weak_match++;
1079                 }
1080                 else {
1081                         matched = refs;
1082                         match++;
1083                 }
1084         }
1085         if (!matched) {
1086                 if (matched_ref)
1087                         *matched_ref = matched_weak;
1088                 return weak_match;
1089         }
1090         else {
1091                 if (matched_ref)
1092                         *matched_ref = matched;
1093                 return match;
1094         }
1095 }
1096
1097 static void tail_link_ref(struct ref *ref, struct ref ***tail)
1098 {
1099         **tail = ref;
1100         while (ref->next)
1101                 ref = ref->next;
1102         *tail = &ref->next;
1103 }
1104
1105 static struct ref *alloc_delete_ref(void)
1106 {
1107         struct ref *ref = alloc_ref("(delete)");
1108         hashclr(ref->new_sha1);
1109         return ref;
1110 }
1111
1112 static int try_explicit_object_name(const char *name,
1113                                     struct ref **match)
1114 {
1115         unsigned char sha1[20];
1116
1117         if (!*name) {
1118                 if (match)
1119                         *match = alloc_delete_ref();
1120                 return 0;
1121         }
1122
1123         if (get_sha1(name, sha1))
1124                 return -1;
1125
1126         if (match) {
1127                 *match = alloc_ref(name);
1128                 hashcpy((*match)->new_sha1, sha1);
1129         }
1130         return 0;
1131 }
1132
1133 static struct ref *make_linked_ref(const char *name, struct ref ***tail)
1134 {
1135         struct ref *ret = alloc_ref(name);
1136         tail_link_ref(ret, tail);
1137         return ret;
1138 }
1139
1140 static char *guess_ref(const char *name, struct ref *peer)
1141 {
1142         struct strbuf buf = STRBUF_INIT;
1143         unsigned char sha1[20];
1144
1145         const char *r = resolve_ref_unsafe(peer->name, RESOLVE_REF_READING,
1146                                            sha1, NULL);
1147         if (!r)
1148                 return NULL;
1149
1150         if (starts_with(r, "refs/heads/"))
1151                 strbuf_addstr(&buf, "refs/heads/");
1152         else if (starts_with(r, "refs/tags/"))
1153                 strbuf_addstr(&buf, "refs/tags/");
1154         else
1155                 return NULL;
1156
1157         strbuf_addstr(&buf, name);
1158         return strbuf_detach(&buf, NULL);
1159 }
1160
1161 static int match_explicit_lhs(struct ref *src,
1162                               struct refspec *rs,
1163                               struct ref **match,
1164                               int *allocated_match)
1165 {
1166         switch (count_refspec_match(rs->src, src, match)) {
1167         case 1:
1168                 if (allocated_match)
1169                         *allocated_match = 0;
1170                 return 0;
1171         case 0:
1172                 /* The source could be in the get_sha1() format
1173                  * not a reference name.  :refs/other is a
1174                  * way to delete 'other' ref at the remote end.
1175                  */
1176                 if (try_explicit_object_name(rs->src, match) < 0)
1177                         return error("src refspec %s does not match any.", rs->src);
1178                 if (allocated_match)
1179                         *allocated_match = 1;
1180                 return 0;
1181         default:
1182                 return error("src refspec %s matches more than one.", rs->src);
1183         }
1184 }
1185
1186 static int match_explicit(struct ref *src, struct ref *dst,
1187                           struct ref ***dst_tail,
1188                           struct refspec *rs)
1189 {
1190         struct ref *matched_src, *matched_dst;
1191         int allocated_src = 0;
1192
1193         const char *dst_value = rs->dst;
1194         char *dst_guess;
1195
1196         if (rs->pattern || rs->matching)
1197                 return 0;
1198
1199         matched_src = matched_dst = NULL;
1200         if (match_explicit_lhs(src, rs, &matched_src, &allocated_src) < 0)
1201                 return -1;
1202
1203         if (!dst_value) {
1204                 unsigned char sha1[20];
1205                 int flag;
1206
1207                 dst_value = resolve_ref_unsafe(matched_src->name,
1208                                                RESOLVE_REF_READING,
1209                                                sha1, &flag);
1210                 if (!dst_value ||
1211                     ((flag & REF_ISSYMREF) &&
1212                      !starts_with(dst_value, "refs/heads/")))
1213                         die("%s cannot be resolved to branch.",
1214                             matched_src->name);
1215         }
1216
1217         switch (count_refspec_match(dst_value, dst, &matched_dst)) {
1218         case 1:
1219                 break;
1220         case 0:
1221                 if (starts_with(dst_value, "refs/"))
1222                         matched_dst = make_linked_ref(dst_value, dst_tail);
1223                 else if (is_null_sha1(matched_src->new_sha1))
1224                         error("unable to delete '%s': remote ref does not exist",
1225                               dst_value);
1226                 else if ((dst_guess = guess_ref(dst_value, matched_src)))
1227                         matched_dst = make_linked_ref(dst_guess, dst_tail);
1228                 else
1229                         error("unable to push to unqualified destination: %s\n"
1230                               "The destination refspec neither matches an "
1231                               "existing ref on the remote nor\n"
1232                               "begins with refs/, and we are unable to "
1233                               "guess a prefix based on the source ref.",
1234                               dst_value);
1235                 break;
1236         default:
1237                 matched_dst = NULL;
1238                 error("dst refspec %s matches more than one.",
1239                       dst_value);
1240                 break;
1241         }
1242         if (!matched_dst)
1243                 return -1;
1244         if (matched_dst->peer_ref)
1245                 return error("dst ref %s receives from more than one src.",
1246                       matched_dst->name);
1247         else {
1248                 matched_dst->peer_ref = allocated_src ?
1249                                         matched_src :
1250                                         copy_ref(matched_src);
1251                 matched_dst->force = rs->force;
1252         }
1253         return 0;
1254 }
1255
1256 static int match_explicit_refs(struct ref *src, struct ref *dst,
1257                                struct ref ***dst_tail, struct refspec *rs,
1258                                int rs_nr)
1259 {
1260         int i, errs;
1261         for (i = errs = 0; i < rs_nr; i++)
1262                 errs += match_explicit(src, dst, dst_tail, &rs[i]);
1263         return errs;
1264 }
1265
1266 static char *get_ref_match(const struct refspec *rs, int rs_nr, const struct ref *ref,
1267                 int send_mirror, int direction, const struct refspec **ret_pat)
1268 {
1269         const struct refspec *pat;
1270         char *name;
1271         int i;
1272         int matching_refs = -1;
1273         for (i = 0; i < rs_nr; i++) {
1274                 if (rs[i].matching &&
1275                     (matching_refs == -1 || rs[i].force)) {
1276                         matching_refs = i;
1277                         continue;
1278                 }
1279
1280                 if (rs[i].pattern) {
1281                         const char *dst_side = rs[i].dst ? rs[i].dst : rs[i].src;
1282                         int match;
1283                         if (direction == FROM_SRC)
1284                                 match = match_name_with_pattern(rs[i].src, ref->name, dst_side, &name);
1285                         else
1286                                 match = match_name_with_pattern(dst_side, ref->name, rs[i].src, &name);
1287                         if (match) {
1288                                 matching_refs = i;
1289                                 break;
1290                         }
1291                 }
1292         }
1293         if (matching_refs == -1)
1294                 return NULL;
1295
1296         pat = rs + matching_refs;
1297         if (pat->matching) {
1298                 /*
1299                  * "matching refs"; traditionally we pushed everything
1300                  * including refs outside refs/heads/ hierarchy, but
1301                  * that does not make much sense these days.
1302                  */
1303                 if (!send_mirror && !starts_with(ref->name, "refs/heads/"))
1304                         return NULL;
1305                 name = xstrdup(ref->name);
1306         }
1307         if (ret_pat)
1308                 *ret_pat = pat;
1309         return name;
1310 }
1311
1312 static struct ref **tail_ref(struct ref **head)
1313 {
1314         struct ref **tail = head;
1315         while (*tail)
1316                 tail = &((*tail)->next);
1317         return tail;
1318 }
1319
1320 struct tips {
1321         struct commit **tip;
1322         int nr, alloc;
1323 };
1324
1325 static void add_to_tips(struct tips *tips, const unsigned char *sha1)
1326 {
1327         struct commit *commit;
1328
1329         if (is_null_sha1(sha1))
1330                 return;
1331         commit = lookup_commit_reference_gently(sha1, 1);
1332         if (!commit || (commit->object.flags & TMP_MARK))
1333                 return;
1334         commit->object.flags |= TMP_MARK;
1335         ALLOC_GROW(tips->tip, tips->nr + 1, tips->alloc);
1336         tips->tip[tips->nr++] = commit;
1337 }
1338
1339 static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***dst_tail)
1340 {
1341         struct string_list dst_tag = STRING_LIST_INIT_NODUP;
1342         struct string_list src_tag = STRING_LIST_INIT_NODUP;
1343         struct string_list_item *item;
1344         struct ref *ref;
1345         struct tips sent_tips;
1346
1347         /*
1348          * Collect everything we know they would have at the end of
1349          * this push, and collect all tags they have.
1350          */
1351         memset(&sent_tips, 0, sizeof(sent_tips));
1352         for (ref = *dst; ref; ref = ref->next) {
1353                 if (ref->peer_ref &&
1354                     !is_null_sha1(ref->peer_ref->new_sha1))
1355                         add_to_tips(&sent_tips, ref->peer_ref->new_sha1);
1356                 else
1357                         add_to_tips(&sent_tips, ref->old_sha1);
1358                 if (starts_with(ref->name, "refs/tags/"))
1359                         string_list_append(&dst_tag, ref->name);
1360         }
1361         clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
1362
1363         string_list_sort(&dst_tag);
1364
1365         /* Collect tags they do not have. */
1366         for (ref = src; ref; ref = ref->next) {
1367                 if (!starts_with(ref->name, "refs/tags/"))
1368                         continue; /* not a tag */
1369                 if (string_list_has_string(&dst_tag, ref->name))
1370                         continue; /* they already have it */
1371                 if (sha1_object_info(ref->new_sha1, NULL) != OBJ_TAG)
1372                         continue; /* be conservative */
1373                 item = string_list_append(&src_tag, ref->name);
1374                 item->util = ref;
1375         }
1376         string_list_clear(&dst_tag, 0);
1377
1378         /*
1379          * At this point, src_tag lists tags that are missing from
1380          * dst, and sent_tips lists the tips we are pushing or those
1381          * that we know they already have. An element in the src_tag
1382          * that is an ancestor of any of the sent_tips needs to be
1383          * sent to the other side.
1384          */
1385         if (sent_tips.nr) {
1386                 for_each_string_list_item(item, &src_tag) {
1387                         struct ref *ref = item->util;
1388                         struct ref *dst_ref;
1389                         struct commit *commit;
1390
1391                         if (is_null_sha1(ref->new_sha1))
1392                                 continue;
1393                         commit = lookup_commit_reference_gently(ref->new_sha1, 1);
1394                         if (!commit)
1395                                 /* not pushing a commit, which is not an error */
1396                                 continue;
1397
1398                         /*
1399                          * Is this tag, which they do not have, reachable from
1400                          * any of the commits we are sending?
1401                          */
1402                         if (!in_merge_bases_many(commit, sent_tips.nr, sent_tips.tip))
1403                                 continue;
1404
1405                         /* Add it in */
1406                         dst_ref = make_linked_ref(ref->name, dst_tail);
1407                         hashcpy(dst_ref->new_sha1, ref->new_sha1);
1408                         dst_ref->peer_ref = copy_ref(ref);
1409                 }
1410         }
1411         string_list_clear(&src_tag, 0);
1412         free(sent_tips.tip);
1413 }
1414
1415 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1416 {
1417         for ( ; list; list = list->next)
1418                 if (!strcmp(list->name, name))
1419                         return (struct ref *)list;
1420         return NULL;
1421 }
1422
1423 static void prepare_ref_index(struct string_list *ref_index, struct ref *ref)
1424 {
1425         for ( ; ref; ref = ref->next)
1426                 string_list_append_nodup(ref_index, ref->name)->util = ref;
1427
1428         string_list_sort(ref_index);
1429 }
1430
1431 /*
1432  * Given only the set of local refs, sanity-check the set of push
1433  * refspecs. We can't catch all errors that match_push_refs would,
1434  * but we can catch some errors early before even talking to the
1435  * remote side.
1436  */
1437 int check_push_refs(struct ref *src, int nr_refspec, const char **refspec_names)
1438 {
1439         struct refspec *refspec = parse_push_refspec(nr_refspec, refspec_names);
1440         int ret = 0;
1441         int i;
1442
1443         for (i = 0; i < nr_refspec; i++) {
1444                 struct refspec *rs = refspec + i;
1445
1446                 if (rs->pattern || rs->matching)
1447                         continue;
1448
1449                 ret |= match_explicit_lhs(src, rs, NULL, NULL);
1450         }
1451
1452         free_refspec(nr_refspec, refspec);
1453         return ret;
1454 }
1455
1456 /*
1457  * Given the set of refs the local repository has, the set of refs the
1458  * remote repository has, and the refspec used for push, determine
1459  * what remote refs we will update and with what value by setting
1460  * peer_ref (which object is being pushed) and force (if the push is
1461  * forced) in elements of "dst". The function may add new elements to
1462  * dst (e.g. pushing to a new branch, done in match_explicit_refs).
1463  */
1464 int match_push_refs(struct ref *src, struct ref **dst,
1465                     int nr_refspec, const char **refspec, int flags)
1466 {
1467         struct refspec *rs;
1468         int send_all = flags & MATCH_REFS_ALL;
1469         int send_mirror = flags & MATCH_REFS_MIRROR;
1470         int send_prune = flags & MATCH_REFS_PRUNE;
1471         int errs;
1472         static const char *default_refspec[] = { ":", NULL };
1473         struct ref *ref, **dst_tail = tail_ref(dst);
1474         struct string_list dst_ref_index = STRING_LIST_INIT_NODUP;
1475
1476         if (!nr_refspec) {
1477                 nr_refspec = 1;
1478                 refspec = default_refspec;
1479         }
1480         rs = parse_push_refspec(nr_refspec, (const char **) refspec);
1481         errs = match_explicit_refs(src, *dst, &dst_tail, rs, nr_refspec);
1482
1483         /* pick the remainder */
1484         for (ref = src; ref; ref = ref->next) {
1485                 struct string_list_item *dst_item;
1486                 struct ref *dst_peer;
1487                 const struct refspec *pat = NULL;
1488                 char *dst_name;
1489
1490                 dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
1491                 if (!dst_name)
1492                         continue;
1493
1494                 if (!dst_ref_index.nr)
1495                         prepare_ref_index(&dst_ref_index, *dst);
1496
1497                 dst_item = string_list_lookup(&dst_ref_index, dst_name);
1498                 dst_peer = dst_item ? dst_item->util : NULL;
1499                 if (dst_peer) {
1500                         if (dst_peer->peer_ref)
1501                                 /* We're already sending something to this ref. */
1502                                 goto free_name;
1503                 } else {
1504                         if (pat->matching && !(send_all || send_mirror))
1505                                 /*
1506                                  * Remote doesn't have it, and we have no
1507                                  * explicit pattern, and we don't have
1508                                  * --all or --mirror.
1509                                  */
1510                                 goto free_name;
1511
1512                         /* Create a new one and link it */
1513                         dst_peer = make_linked_ref(dst_name, &dst_tail);
1514                         hashcpy(dst_peer->new_sha1, ref->new_sha1);
1515                         string_list_insert(&dst_ref_index,
1516                                 dst_peer->name)->util = dst_peer;
1517                 }
1518                 dst_peer->peer_ref = copy_ref(ref);
1519                 dst_peer->force = pat->force;
1520         free_name:
1521                 free(dst_name);
1522         }
1523
1524         string_list_clear(&dst_ref_index, 0);
1525
1526         if (flags & MATCH_REFS_FOLLOW_TAGS)
1527                 add_missing_tags(src, dst, &dst_tail);
1528
1529         if (send_prune) {
1530                 struct string_list src_ref_index = STRING_LIST_INIT_NODUP;
1531                 /* check for missing refs on the remote */
1532                 for (ref = *dst; ref; ref = ref->next) {
1533                         char *src_name;
1534
1535                         if (ref->peer_ref)
1536                                 /* We're already sending something to this ref. */
1537                                 continue;
1538
1539                         src_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_DST, NULL);
1540                         if (src_name) {
1541                                 if (!src_ref_index.nr)
1542                                         prepare_ref_index(&src_ref_index, src);
1543                                 if (!string_list_has_string(&src_ref_index,
1544                                             src_name))
1545                                         ref->peer_ref = alloc_delete_ref();
1546                                 free(src_name);
1547                         }
1548                 }
1549                 string_list_clear(&src_ref_index, 0);
1550         }
1551         if (errs)
1552                 return -1;
1553         return 0;
1554 }
1555
1556 void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
1557                              int force_update)
1558 {
1559         struct ref *ref;
1560
1561         for (ref = remote_refs; ref; ref = ref->next) {
1562                 int force_ref_update = ref->force || force_update;
1563                 int reject_reason = 0;
1564
1565                 if (ref->peer_ref)
1566                         hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
1567                 else if (!send_mirror)
1568                         continue;
1569
1570                 ref->deletion = is_null_sha1(ref->new_sha1);
1571                 if (!ref->deletion &&
1572                         !hashcmp(ref->old_sha1, ref->new_sha1)) {
1573                         ref->status = REF_STATUS_UPTODATE;
1574                         continue;
1575                 }
1576
1577                 /*
1578                  * Bypass the usual "must fast-forward" check but
1579                  * replace it with a weaker "the old value must be
1580                  * this value we observed".  If the remote ref has
1581                  * moved and is now different from what we expect,
1582                  * reject any push.
1583                  *
1584                  * It also is an error if the user told us to check
1585                  * with the remote-tracking branch to find the value
1586                  * to expect, but we did not have such a tracking
1587                  * branch.
1588                  */
1589                 if (ref->expect_old_sha1) {
1590                         if (ref->expect_old_no_trackback ||
1591                             hashcmp(ref->old_sha1, ref->old_sha1_expect))
1592                                 reject_reason = REF_STATUS_REJECT_STALE;
1593                 }
1594
1595                 /*
1596                  * The usual "must fast-forward" rules.
1597                  *
1598                  * Decide whether an individual refspec A:B can be
1599                  * pushed.  The push will succeed if any of the
1600                  * following are true:
1601                  *
1602                  * (1) the remote reference B does not exist
1603                  *
1604                  * (2) the remote reference B is being removed (i.e.,
1605                  *     pushing :B where no source is specified)
1606                  *
1607                  * (3) the destination is not under refs/tags/, and
1608                  *     if the old and new value is a commit, the new
1609                  *     is a descendant of the old.
1610                  *
1611                  * (4) it is forced using the +A:B notation, or by
1612                  *     passing the --force argument
1613                  */
1614
1615                 else if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
1616                         if (starts_with(ref->name, "refs/tags/"))
1617                                 reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
1618                         else if (!has_sha1_file(ref->old_sha1))
1619                                 reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
1620                         else if (!lookup_commit_reference_gently(ref->old_sha1, 1) ||
1621                                  !lookup_commit_reference_gently(ref->new_sha1, 1))
1622                                 reject_reason = REF_STATUS_REJECT_NEEDS_FORCE;
1623                         else if (!ref_newer(ref->new_sha1, ref->old_sha1))
1624                                 reject_reason = REF_STATUS_REJECT_NONFASTFORWARD;
1625                 }
1626
1627                 /*
1628                  * "--force" will defeat any rejection implemented
1629                  * by the rules above.
1630                  */
1631                 if (!force_ref_update)
1632                         ref->status = reject_reason;
1633                 else if (reject_reason)
1634                         ref->forced_update = 1;
1635         }
1636 }
1637
1638 static void set_merge(struct branch *ret)
1639 {
1640         char *ref;
1641         unsigned char sha1[20];
1642         int i;
1643
1644         ret->merge = xcalloc(ret->merge_nr, sizeof(*ret->merge));
1645         for (i = 0; i < ret->merge_nr; i++) {
1646                 ret->merge[i] = xcalloc(1, sizeof(**ret->merge));
1647                 ret->merge[i]->src = xstrdup(ret->merge_name[i]);
1648                 if (!remote_find_tracking(ret->remote, ret->merge[i]) ||
1649                     strcmp(ret->remote_name, "."))
1650                         continue;
1651                 if (dwim_ref(ret->merge_name[i], strlen(ret->merge_name[i]),
1652                              sha1, &ref) == 1)
1653                         ret->merge[i]->dst = ref;
1654                 else
1655                         ret->merge[i]->dst = xstrdup(ret->merge_name[i]);
1656         }
1657 }
1658
1659 struct branch *branch_get(const char *name)
1660 {
1661         struct branch *ret;
1662
1663         read_config();
1664         if (!name || !*name || !strcmp(name, "HEAD"))
1665                 ret = current_branch;
1666         else
1667                 ret = make_branch(name, 0);
1668         if (ret && ret->remote_name) {
1669                 ret->remote = remote_get(ret->remote_name);
1670                 if (ret->merge_nr)
1671                         set_merge(ret);
1672         }
1673         if (ret && ret->pushremote_name && ret->push_name) {
1674                 struct remote *pushremote;
1675                 pushremote = pushremote_get(ret->pushremote_name);
1676                 ret->push.src = xstrdup(ret->push_name);
1677                 if (remote_find_tracking(pushremote, &ret->push)
1678                     && !strcmp(ret->pushremote_name, "."))
1679                         ret->push.dst = xstrdup(ret->push_name);
1680         }
1681         return ret;
1682 }
1683
1684 int branch_has_merge_config(struct branch *branch)
1685 {
1686         return branch && !!branch->merge;
1687 }
1688
1689 int branch_merge_matches(struct branch *branch,
1690                                  int i,
1691                                  const char *refname)
1692 {
1693         if (!branch || i < 0 || i >= branch->merge_nr)
1694                 return 0;
1695         return refname_match(branch->merge[i]->src, refname);
1696 }
1697
1698 static int ignore_symref_update(const char *refname)
1699 {
1700         unsigned char sha1[20];
1701         int flag;
1702
1703         if (!resolve_ref_unsafe(refname, 0, sha1, &flag))
1704                 return 0; /* non-existing refs are OK */
1705         return (flag & REF_ISSYMREF);
1706 }
1707
1708 /*
1709  * Create and return a list of (struct ref) consisting of copies of
1710  * each remote_ref that matches refspec.  refspec must be a pattern.
1711  * Fill in the copies' peer_ref to describe the local tracking refs to
1712  * which they map.  Omit any references that would map to an existing
1713  * local symbolic ref.
1714  */
1715 static struct ref *get_expanded_map(const struct ref *remote_refs,
1716                                     const struct refspec *refspec)
1717 {
1718         const struct ref *ref;
1719         struct ref *ret = NULL;
1720         struct ref **tail = &ret;
1721
1722         for (ref = remote_refs; ref; ref = ref->next) {
1723                 char *expn_name = NULL;
1724
1725                 if (strchr(ref->name, '^'))
1726                         continue; /* a dereference item */
1727                 if (match_name_with_pattern(refspec->src, ref->name,
1728                                             refspec->dst, &expn_name) &&
1729                     !ignore_symref_update(expn_name)) {
1730                         struct ref *cpy = copy_ref(ref);
1731
1732                         cpy->peer_ref = alloc_ref(expn_name);
1733                         if (refspec->force)
1734                                 cpy->peer_ref->force = 1;
1735                         *tail = cpy;
1736                         tail = &cpy->next;
1737                 }
1738                 free(expn_name);
1739         }
1740
1741         return ret;
1742 }
1743
1744 static const struct ref *find_ref_by_name_abbrev(const struct ref *refs, const char *name)
1745 {
1746         const struct ref *ref;
1747         for (ref = refs; ref; ref = ref->next) {
1748                 if (refname_match(name, ref->name))
1749                         return ref;
1750         }
1751         return NULL;
1752 }
1753
1754 struct ref *get_remote_ref(const struct ref *remote_refs, const char *name)
1755 {
1756         const struct ref *ref = find_ref_by_name_abbrev(remote_refs, name);
1757
1758         if (!ref)
1759                 return NULL;
1760
1761         return copy_ref(ref);
1762 }
1763
1764 static struct ref *get_local_ref(const char *name)
1765 {
1766         if (!name || name[0] == '\0')
1767                 return NULL;
1768
1769         if (starts_with(name, "refs/"))
1770                 return alloc_ref(name);
1771
1772         if (starts_with(name, "heads/") ||
1773             starts_with(name, "tags/") ||
1774             starts_with(name, "remotes/"))
1775                 return alloc_ref_with_prefix("refs/", 5, name);
1776
1777         return alloc_ref_with_prefix("refs/heads/", 11, name);
1778 }
1779
1780 int get_fetch_map(const struct ref *remote_refs,
1781                   const struct refspec *refspec,
1782                   struct ref ***tail,
1783                   int missing_ok)
1784 {
1785         struct ref *ref_map, **rmp;
1786
1787         if (refspec->pattern) {
1788                 ref_map = get_expanded_map(remote_refs, refspec);
1789         } else {
1790                 const char *name = refspec->src[0] ? refspec->src : "HEAD";
1791
1792                 if (refspec->exact_sha1) {
1793                         ref_map = alloc_ref(name);
1794                         get_sha1_hex(name, ref_map->old_sha1);
1795                 } else {
1796                         ref_map = get_remote_ref(remote_refs, name);
1797                 }
1798                 if (!missing_ok && !ref_map)
1799                         die("Couldn't find remote ref %s", name);
1800                 if (ref_map) {
1801                         ref_map->peer_ref = get_local_ref(refspec->dst);
1802                         if (ref_map->peer_ref && refspec->force)
1803                                 ref_map->peer_ref->force = 1;
1804                 }
1805         }
1806
1807         for (rmp = &ref_map; *rmp; ) {
1808                 if ((*rmp)->peer_ref) {
1809                         if (!starts_with((*rmp)->peer_ref->name, "refs/") ||
1810                             check_refname_format((*rmp)->peer_ref->name, 0)) {
1811                                 struct ref *ignore = *rmp;
1812                                 error("* Ignoring funny ref '%s' locally",
1813                                       (*rmp)->peer_ref->name);
1814                                 *rmp = (*rmp)->next;
1815                                 free(ignore->peer_ref);
1816                                 free(ignore);
1817                                 continue;
1818                         }
1819                 }
1820                 rmp = &((*rmp)->next);
1821         }
1822
1823         if (ref_map)
1824                 tail_link_ref(ref_map, tail);
1825
1826         return 0;
1827 }
1828
1829 int resolve_remote_symref(struct ref *ref, struct ref *list)
1830 {
1831         if (!ref->symref)
1832                 return 0;
1833         for (; list; list = list->next)
1834                 if (!strcmp(ref->symref, list->name)) {
1835                         hashcpy(ref->old_sha1, list->old_sha1);
1836                         return 0;
1837                 }
1838         return 1;
1839 }
1840
1841 static void unmark_and_free(struct commit_list *list, unsigned int mark)
1842 {
1843         while (list) {
1844                 struct commit_list *temp = list;
1845                 temp->item->object.flags &= ~mark;
1846                 list = temp->next;
1847                 free(temp);
1848         }
1849 }
1850
1851 int ref_newer(const unsigned char *new_sha1, const unsigned char *old_sha1)
1852 {
1853         struct object *o;
1854         struct commit *old, *new;
1855         struct commit_list *list, *used;
1856         int found = 0;
1857
1858         /*
1859          * Both new and old must be commit-ish and new is descendant of
1860          * old.  Otherwise we require --force.
1861          */
1862         o = deref_tag(parse_object(old_sha1), NULL, 0);
1863         if (!o || o->type != OBJ_COMMIT)
1864                 return 0;
1865         old = (struct commit *) o;
1866
1867         o = deref_tag(parse_object(new_sha1), NULL, 0);
1868         if (!o || o->type != OBJ_COMMIT)
1869                 return 0;
1870         new = (struct commit *) o;
1871
1872         if (parse_commit(new) < 0)
1873                 return 0;
1874
1875         used = list = NULL;
1876         commit_list_insert(new, &list);
1877         while (list) {
1878                 new = pop_most_recent_commit(&list, TMP_MARK);
1879                 commit_list_insert(new, &used);
1880                 if (new == old) {
1881                         found = 1;
1882                         break;
1883                 }
1884         }
1885         unmark_and_free(list, TMP_MARK);
1886         unmark_and_free(used, TMP_MARK);
1887         return found;
1888 }
1889
1890 /*
1891  * Compare a branch with its upstream, and save their differences (number
1892  * of commits) in *num_ours and *num_theirs.
1893  *
1894  * Return 0 if branch has no upstream (no base), -1 if upstream is missing
1895  * (with "gone" base), otherwise 1 (with base).
1896  */
1897 int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
1898 {
1899         unsigned char sha1[20];
1900         struct commit *ours, *theirs;
1901         char symmetric[84];
1902         struct rev_info revs;
1903         const char *rev_argv[10], *base;
1904         int rev_argc;
1905
1906         /* Cannot stat unless we are marked to build on top of somebody else. */
1907         if (!branch ||
1908             !branch->merge || !branch->merge[0] || !branch->merge[0]->dst)
1909                 return 0;
1910
1911         /* Cannot stat if what we used to build on no longer exists */
1912         base = branch->merge[0]->dst;
1913         if (read_ref(base, sha1))
1914                 return -1;
1915         theirs = lookup_commit_reference(sha1);
1916         if (!theirs)
1917                 return -1;
1918
1919         if (read_ref(branch->refname, sha1))
1920                 return -1;
1921         ours = lookup_commit_reference(sha1);
1922         if (!ours)
1923                 return -1;
1924
1925         /* are we the same? */
1926         if (theirs == ours) {
1927                 *num_theirs = *num_ours = 0;
1928                 return 1;
1929         }
1930
1931         /* Run "rev-list --left-right ours...theirs" internally... */
1932         rev_argc = 0;
1933         rev_argv[rev_argc++] = NULL;
1934         rev_argv[rev_argc++] = "--left-right";
1935         rev_argv[rev_argc++] = symmetric;
1936         rev_argv[rev_argc++] = "--";
1937         rev_argv[rev_argc] = NULL;
1938
1939         strcpy(symmetric, sha1_to_hex(ours->object.sha1));
1940         strcpy(symmetric + 40, "...");
1941         strcpy(symmetric + 43, sha1_to_hex(theirs->object.sha1));
1942
1943         init_revisions(&revs, NULL);
1944         setup_revisions(rev_argc, rev_argv, &revs, NULL);
1945         if (prepare_revision_walk(&revs))
1946                 die("revision walk setup failed");
1947
1948         /* ... and count the commits on each side. */
1949         *num_ours = 0;
1950         *num_theirs = 0;
1951         while (1) {
1952                 struct commit *c = get_revision(&revs);
1953                 if (!c)
1954                         break;
1955                 if (c->object.flags & SYMMETRIC_LEFT)
1956                         (*num_ours)++;
1957                 else
1958                         (*num_theirs)++;
1959         }
1960
1961         /* clear object flags smudged by the above traversal */
1962         clear_commit_marks(ours, ALL_REV_FLAGS);
1963         clear_commit_marks(theirs, ALL_REV_FLAGS);
1964         return 1;
1965 }
1966
1967 /*
1968  * Return true when there is anything to report, otherwise false.
1969  */
1970 int format_tracking_info(struct branch *branch, struct strbuf *sb)
1971 {
1972         int ours, theirs;
1973         char *base;
1974         int upstream_is_gone = 0;
1975
1976         switch (stat_tracking_info(branch, &ours, &theirs)) {
1977         case 0:
1978                 /* no base */
1979                 return 0;
1980         case -1:
1981                 /* with "gone" base */
1982                 upstream_is_gone = 1;
1983                 break;
1984         default:
1985                 /* with base */
1986                 break;
1987         }
1988
1989         base = shorten_unambiguous_ref(branch->merge[0]->dst, 0);
1990         if (upstream_is_gone) {
1991                 strbuf_addf(sb,
1992                         _("Your branch is based on '%s', but the upstream is gone.\n"),
1993                         base);
1994                 if (advice_status_hints)
1995                         strbuf_addf(sb,
1996                                 _("  (use \"git branch --unset-upstream\" to fixup)\n"));
1997         } else if (!ours && !theirs) {
1998                 strbuf_addf(sb,
1999                         _("Your branch is up-to-date with '%s'.\n"),
2000                         base);
2001         } else if (!theirs) {
2002                 strbuf_addf(sb,
2003                         Q_("Your branch is ahead of '%s' by %d commit.\n",
2004                            "Your branch is ahead of '%s' by %d commits.\n",
2005                            ours),
2006                         base, ours);
2007                 if (advice_status_hints && !branch->push.dst)
2008                         strbuf_addf(sb,
2009                                 _("  (use \"git push\" to publish your local commits)\n"));
2010         } else if (!ours) {
2011                 strbuf_addf(sb,
2012                         Q_("Your branch is behind '%s' by %d commit, "
2013                                "and can be fast-forwarded.\n",
2014                            "Your branch is behind '%s' by %d commits, "
2015                                "and can be fast-forwarded.\n",
2016                            theirs),
2017                         base, theirs);
2018                 if (advice_status_hints)
2019                         strbuf_addf(sb,
2020                                 _("  (use \"git pull\" to update your local branch)\n"));
2021         } else {
2022                 strbuf_addf(sb,
2023                         Q_("Your branch and '%s' have diverged,\n"
2024                                "and have %d and %d different commit each, "
2025                                "respectively.\n",
2026                            "Your branch and '%s' have diverged,\n"
2027                                "and have %d and %d different commits each, "
2028                                "respectively.\n",
2029                            theirs),
2030                         base, ours, theirs);
2031                 if (advice_status_hints)
2032                         strbuf_addf(sb,
2033                                 _("  (use \"git pull\" to merge the remote branch into yours)\n"));
2034         }
2035         if (branch->push.dst) {
2036                 unsigned char local_sha1[20];
2037                 unsigned char remote_sha1[20];
2038                 const char *pub;
2039
2040                 pub = shorten_unambiguous_ref(branch->push.dst, 0);
2041
2042                 /* Is it published? */
2043                 if (!read_ref(branch->refname, local_sha1) &&
2044                                 !read_ref(branch->push.dst, remote_sha1)) {
2045                         if (hashcmp(local_sha1, remote_sha1)) {
2046                                 strbuf_addf(sb, _("Some commits haven't been published to '%s'.\n"), pub);
2047                                 if (advice_status_hints)
2048                                         strbuf_addf(sb, _("  (use \"git push\" to publish your local commits)\n"));
2049                         }
2050                 }
2051         }
2052         free(base);
2053         return 1;
2054 }
2055
2056 static int one_local_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
2057 {
2058         struct ref ***local_tail = cb_data;
2059         struct ref *ref;
2060         int len;
2061
2062         /* we already know it starts with refs/ to get here */
2063         if (check_refname_format(refname + 5, 0))
2064                 return 0;
2065
2066         len = strlen(refname) + 1;
2067         ref = xcalloc(1, sizeof(*ref) + len);
2068         hashcpy(ref->new_sha1, sha1);
2069         memcpy(ref->name, refname, len);
2070         **local_tail = ref;
2071         *local_tail = &ref->next;
2072         return 0;
2073 }
2074
2075 struct ref *get_local_heads(void)
2076 {
2077         struct ref *local_refs = NULL, **local_tail = &local_refs;
2078         for_each_ref(one_local_ref, &local_tail);
2079         return local_refs;
2080 }
2081
2082 struct ref *guess_remote_head(const struct ref *head,
2083                               const struct ref *refs,
2084                               int all)
2085 {
2086         const struct ref *r;
2087         struct ref *list = NULL;
2088         struct ref **tail = &list;
2089
2090         if (!head)
2091                 return NULL;
2092
2093         /*
2094          * Some transports support directly peeking at
2095          * where HEAD points; if that is the case, then
2096          * we don't have to guess.
2097          */
2098         if (head->symref)
2099                 return copy_ref(find_ref_by_name(refs, head->symref));
2100
2101         /* If refs/heads/master could be right, it is. */
2102         if (!all) {
2103                 r = find_ref_by_name(refs, "refs/heads/master");
2104                 if (r && !hashcmp(r->old_sha1, head->old_sha1))
2105                         return copy_ref(r);
2106         }
2107
2108         /* Look for another ref that points there */
2109         for (r = refs; r; r = r->next) {
2110                 if (r != head &&
2111                     starts_with(r->name, "refs/heads/") &&
2112                     !hashcmp(r->old_sha1, head->old_sha1)) {
2113                         *tail = copy_ref(r);
2114                         tail = &((*tail)->next);
2115                         if (!all)
2116                                 break;
2117                 }
2118         }
2119
2120         return list;
2121 }
2122
2123 struct stale_heads_info {
2124         struct string_list *ref_names;
2125         struct ref **stale_refs_tail;
2126         struct refspec *refs;
2127         int ref_count;
2128 };
2129
2130 static int get_stale_heads_cb(const char *refname,
2131         const unsigned char *sha1, int flags, void *cb_data)
2132 {
2133         struct stale_heads_info *info = cb_data;
2134         struct string_list matches = STRING_LIST_INIT_DUP;
2135         struct refspec query;
2136         int i, stale = 1;
2137         memset(&query, 0, sizeof(struct refspec));
2138         query.dst = (char *)refname;
2139
2140         query_refspecs_multiple(info->refs, info->ref_count, &query, &matches);
2141         if (matches.nr == 0)
2142                 goto clean_exit; /* No matches */
2143
2144         /*
2145          * If we did find a suitable refspec and it's not a symref and
2146          * it's not in the list of refs that currently exist in that
2147          * remote, we consider it to be stale. In order to deal with
2148          * overlapping refspecs, we need to go over all of the
2149          * matching refs.
2150          */
2151         if (flags & REF_ISSYMREF)
2152                 goto clean_exit;
2153
2154         for (i = 0; stale && i < matches.nr; i++)
2155                 if (string_list_has_string(info->ref_names, matches.items[i].string))
2156                         stale = 0;
2157
2158         if (stale) {
2159                 struct ref *ref = make_linked_ref(refname, &info->stale_refs_tail);
2160                 hashcpy(ref->new_sha1, sha1);
2161         }
2162
2163 clean_exit:
2164         string_list_clear(&matches, 0);
2165         return 0;
2166 }
2167
2168 struct ref *get_stale_heads(struct refspec *refs, int ref_count, struct ref *fetch_map)
2169 {
2170         struct ref *ref, *stale_refs = NULL;
2171         struct string_list ref_names = STRING_LIST_INIT_NODUP;
2172         struct stale_heads_info info;
2173         info.ref_names = &ref_names;
2174         info.stale_refs_tail = &stale_refs;
2175         info.refs = refs;
2176         info.ref_count = ref_count;
2177         for (ref = fetch_map; ref; ref = ref->next)
2178                 string_list_append(&ref_names, ref->name);
2179         string_list_sort(&ref_names);
2180         for_each_ref(get_stale_heads_cb, &info);
2181         string_list_clear(&ref_names, 0);
2182         return stale_refs;
2183 }
2184
2185 /*
2186  * Compare-and-swap
2187  */
2188 void clear_cas_option(struct push_cas_option *cas)
2189 {
2190         int i;
2191
2192         for (i = 0; i < cas->nr; i++)
2193                 free(cas->entry[i].refname);
2194         free(cas->entry);
2195         memset(cas, 0, sizeof(*cas));
2196 }
2197
2198 static struct push_cas *add_cas_entry(struct push_cas_option *cas,
2199                                       const char *refname,
2200                                       size_t refnamelen)
2201 {
2202         struct push_cas *entry;
2203         ALLOC_GROW(cas->entry, cas->nr + 1, cas->alloc);
2204         entry = &cas->entry[cas->nr++];
2205         memset(entry, 0, sizeof(*entry));
2206         entry->refname = xmemdupz(refname, refnamelen);
2207         return entry;
2208 }
2209
2210 int parse_push_cas_option(struct push_cas_option *cas, const char *arg, int unset)
2211 {
2212         const char *colon;
2213         struct push_cas *entry;
2214
2215         if (unset) {
2216                 /* "--no-<option>" */
2217                 clear_cas_option(cas);
2218                 return 0;
2219         }
2220
2221         if (!arg) {
2222                 /* just "--<option>" */
2223                 cas->use_tracking_for_rest = 1;
2224                 return 0;
2225         }
2226
2227         /* "--<option>=refname" or "--<option>=refname:value" */
2228         colon = strchrnul(arg, ':');
2229         entry = add_cas_entry(cas, arg, colon - arg);
2230         if (!*colon)
2231                 entry->use_tracking = 1;
2232         else if (get_sha1(colon + 1, entry->expect))
2233                 return error("cannot parse expected object name '%s'", colon + 1);
2234         return 0;
2235 }
2236
2237 int parseopt_push_cas_option(const struct option *opt, const char *arg, int unset)
2238 {
2239         return parse_push_cas_option(opt->value, arg, unset);
2240 }
2241
2242 int is_empty_cas(const struct push_cas_option *cas)
2243 {
2244         return !cas->use_tracking_for_rest && !cas->nr;
2245 }
2246
2247 /*
2248  * Look at remote.fetch refspec and see if we have a remote
2249  * tracking branch for the refname there.  Fill its current
2250  * value in sha1[].
2251  * If we cannot do so, return negative to signal an error.
2252  */
2253 static int remote_tracking(struct remote *remote, const char *refname,
2254                            unsigned char sha1[20])
2255 {
2256         char *dst;
2257
2258         dst = apply_refspecs(remote->fetch, remote->fetch_refspec_nr, refname);
2259         if (!dst)
2260                 return -1; /* no tracking ref for refname at remote */
2261         if (read_ref(dst, sha1))
2262                 return -1; /* we know what the tracking ref is but we cannot read it */
2263         return 0;
2264 }
2265
2266 static void apply_cas(struct push_cas_option *cas,
2267                       struct remote *remote,
2268                       struct ref *ref)
2269 {
2270         int i;
2271
2272         /* Find an explicit --<option>=<name>[:<value>] entry */
2273         for (i = 0; i < cas->nr; i++) {
2274                 struct push_cas *entry = &cas->entry[i];
2275                 if (!refname_match(entry->refname, ref->name))
2276                         continue;
2277                 ref->expect_old_sha1 = 1;
2278                 if (!entry->use_tracking)
2279                         hashcpy(ref->old_sha1_expect, cas->entry[i].expect);
2280                 else if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2281                         ref->expect_old_no_trackback = 1;
2282                 return;
2283         }
2284
2285         /* Are we using "--<option>" to cover all? */
2286         if (!cas->use_tracking_for_rest)
2287                 return;
2288
2289         ref->expect_old_sha1 = 1;
2290         if (remote_tracking(remote, ref->name, ref->old_sha1_expect))
2291                 ref->expect_old_no_trackback = 1;
2292 }
2293
2294 void apply_push_cas(struct push_cas_option *cas,
2295                     struct remote *remote,
2296                     struct ref *remote_refs)
2297 {
2298         struct ref *ref;
2299         for (ref = remote_refs; ref; ref = ref->next)
2300                 apply_cas(cas, remote, ref);
2301 }