remote.c

   1 #include "cache.h"
   2 #include "remote.h"
   3 #include "refs.h"
   4
   5 static struct remote **remotes;
   6 static int allocated_remotes;
   7
   8 #define BUF_SIZE (2048)
   9 static char buffer[BUF_SIZE];
  10
  11 static void add_push_refspec(struct remote *remote, const char *ref)
  12 {
  13         int nr = remote->push_refspec_nr + 1;
  14         remote->push_refspec =
  15                 xrealloc(remote->push_refspec, nr * sizeof(char *));
  16         remote->push_refspec[nr-1] = ref;
  17         remote->push_refspec_nr = nr;
  18 }
  19
  20 static void add_fetch_refspec(struct remote *remote, const char *ref)
  21 {
  22         int nr = remote->fetch_refspec_nr + 1;
  23         remote->fetch_refspec =
  24                 xrealloc(remote->fetch_refspec, nr * sizeof(char *));
  25         remote->fetch_refspec[nr-1] = ref;
  26         remote->fetch_refspec_nr = nr;
  27 }
  28
  29 static void add_uri(struct remote *remote, const char *uri)
  30 {
  31         int nr = remote->uri_nr + 1;
  32         remote->uri =
  33                 xrealloc(remote->uri, nr * sizeof(char *));
  34         remote->uri[nr-1] = uri;
  35         remote->uri_nr = nr;
  36 }
  37
  38 static struct remote *make_remote(const char *name, int len)
  39 {
  40         int i, empty = -1;
  41
  42         for (i = 0; i < allocated_remotes; i++) {
  43                 if (!remotes[i]) {
  44                         if (empty < 0)
  45                                 empty = i;
  46                 } else {
  47                         if (len ? (!strncmp(name, remotes[i]->name, len) &&
  48                                    !remotes[i]->name[len]) :
  49                             !strcmp(name, remotes[i]->name))
  50                                 return remotes[i];
  51                 }
  52         }
  53
  54         if (empty < 0) {
  55                 empty = allocated_remotes;
  56                 allocated_remotes += allocated_remotes ? allocated_remotes : 1;
  57                 remotes = xrealloc(remotes,
  58                                    sizeof(*remotes) * allocated_remotes);
  59                 memset(remotes + empty, 0,
  60                        (allocated_remotes - empty) * sizeof(*remotes));
  61         }
  62         remotes[empty] = xcalloc(1, sizeof(struct remote));
  63         if (len)
  64                 remotes[empty]->name = xstrndup(name, len);
  65         else
  66                 remotes[empty]->name = xstrdup(name);
  67         return remotes[empty];
  68 }
  69
  70 static void read_remotes_file(struct remote *remote)
  71 {
  72         FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
  73
  74         if (!f)
  75                 return;
  76         while (fgets(buffer, BUF_SIZE, f)) {
  77                 int value_list;
  78                 char *s, *p;
  79
  80                 if (!prefixcmp(buffer, "URL:")) {
  81                         value_list = 0;
  82                         s = buffer + 4;
  83                 } else if (!prefixcmp(buffer, "Push:")) {
  84                         value_list = 1;
  85                         s = buffer + 5;
  86                 } else if (!prefixcmp(buffer, "Pull:")) {
  87                         value_list = 2;
  88                         s = buffer + 5;
  89                 } else
  90                         continue;
  91
  92                 while (isspace(*s))
  93                         s++;
  94                 if (!*s)
  95                         continue;
  96
  97                 p = s + strlen(s);
  98                 while (isspace(p[-1]))
  99                         *--p = 0;
 100
 101                 switch (value_list) {
 102                 case 0:
 103                         add_uri(remote, xstrdup(s));
 104                         break;
 105                 case 1:
 106                         add_push_refspec(remote, xstrdup(s));
 107                         break;
 108                 case 2:
 109                         add_fetch_refspec(remote, xstrdup(s));
 110                         break;
 111                 }
 112         }
 113         fclose(f);
 114 }
 115
 116 static void read_branches_file(struct remote *remote)
 117 {
 118         const char *slash = strchr(remote->name, '/');
 119         int n = slash ? slash - remote->name : 1000;
 120         FILE *f = fopen(git_path("branches/%.*s", n, remote->name), "r");
 121         char *s, *p;
 122         int len;
 123
 124         if (!f)
 125                 return;
 126         s = fgets(buffer, BUF_SIZE, f);
 127         fclose(f);
 128         if (!s)
 129                 return;
 130         while (isspace(*s))
 131                 s++;
 132         if (!*s)
 133                 return;
 134         p = s + strlen(s);
 135         while (isspace(p[-1]))
 136                 *--p = 0;
 137         len = p - s;
 138         if (slash)
 139                 len += strlen(slash);
 140         p = xmalloc(len + 1);
 141         strcpy(p, s);
 142         if (slash)
 143                 strcat(p, slash);
 144         add_uri(remote, p);
 145 }
 146
 147 static char *default_remote_name = NULL;
 148 static const char *current_branch = NULL;
 149 static int current_branch_len = 0;
 150
 151 static int handle_config(const char *key, const char *value)
 152 {
 153         const char *name;
 154         const char *subkey;
 155         struct remote *remote;
 156         if (!prefixcmp(key, "branch.") && current_branch &&
 157             !strncmp(key + 7, current_branch, current_branch_len) &&
 158             !strcmp(key + 7 + current_branch_len, ".remote")) {
 159                 free(default_remote_name);
 160                 default_remote_name = xstrdup(value);
 161         }
 162         if (prefixcmp(key,  "remote."))
 163                 return 0;
 164         name = key + 7;
 165         subkey = strrchr(name, '.');
 166         if (!subkey)
 167                 return error("Config with no key for remote %s", name);
 168         if (*subkey == '/') {
 169                 warning("Config remote shorthand cannot begin with '/': %s", name);
 170                 return 0;
 171         }
 172         remote = make_remote(name, subkey - name);
 173         if (!value) {
 174                 /* if we ever have a boolean variable, e.g. "remote.*.disabled"
 175                  * [remote "frotz"]
 176                  *      disabled
 177                  * is a valid way to set it to true; we get NULL in value so
 178                  * we need to handle it here.
 179                  *
 180                  * if (!strcmp(subkey, ".disabled")) {
 181                  *      val = git_config_bool(key, value);
 182                  *      return 0;
 183                  * } else
 184                  *
 185                  */
 186                 return 0; /* ignore unknown booleans */
 187         }
 188         if (!strcmp(subkey, ".url")) {
 189                 add_uri(remote, xstrdup(value));
 190         } else if (!strcmp(subkey, ".push")) {
 191                 add_push_refspec(remote, xstrdup(value));
 192         } else if (!strcmp(subkey, ".fetch")) {
 193                 add_fetch_refspec(remote, xstrdup(value));
 194         } else if (!strcmp(subkey, ".receivepack")) {
 195                 if (!remote->receivepack)
 196                         remote->receivepack = xstrdup(value);
 197                 else
 198                         error("more than one receivepack given, using the first");
 199         } else if (!strcmp(subkey, ".uploadpack")) {
 200                 if (!remote->uploadpack)
 201                         remote->uploadpack = xstrdup(value);
 202                 else
 203                         error("more than one uploadpack given, using the first");
 204         }
 205         return 0;
 206 }
 207
 208 static void read_config(void)
 209 {
 210         unsigned char sha1[20];
 211         const char *head_ref;
 212         int flag;
 213         if (default_remote_name) // did this already
 214                 return;
 215         default_remote_name = xstrdup("origin");
 216         current_branch = NULL;
 217         head_ref = resolve_ref("HEAD", sha1, 0, &flag);
 218         if (head_ref && (flag & REF_ISSYMREF) &&
 219             !prefixcmp(head_ref, "refs/heads/")) {
 220                 current_branch = head_ref + strlen("refs/heads/");
 221                 current_branch_len = strlen(current_branch);
 222         }
 223         git_config(handle_config);
 224 }
 225
 226 static struct refspec *parse_ref_spec(int nr_refspec, const char **refspec)
 227 {
 228         int i;
 229         struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 230         for (i = 0; i < nr_refspec; i++) {
 231                 const char *sp, *ep, *gp;
 232                 sp = refspec[i];
 233                 if (*sp == '+') {
 234                         rs[i].force = 1;
 235                         sp++;
 236                 }
 237                 gp = strchr(sp, '*');
 238                 ep = strchr(sp, ':');
 239                 if (gp && ep && gp > ep)
 240                         gp = NULL;
 241                 if (ep) {
 242                         if (ep[1]) {
 243                                 const char *glob = strchr(ep + 1, '*');
 244                                 if (!glob)
 245                                         gp = NULL;
 246                                 if (gp)
 247                                         rs[i].dst = xstrndup(ep + 1,
 248                                                              glob - ep - 1);
 249                                 else
 250                                         rs[i].dst = xstrdup(ep + 1);
 251                         }
 252                 } else {
 253                         ep = sp + strlen(sp);
 254                 }
 255                 if (gp) {
 256                         rs[i].pattern = 1;
 257                         ep = gp;
 258                 }
 259                 rs[i].src = xstrndup(sp, ep - sp);
 260         }
 261         return rs;
 262 }
 263
 264 struct remote *remote_get(const char *name)
 265 {
 266         struct remote *ret;
 267
 268         read_config();
 269         if (!name)
 270                 name = default_remote_name;
 271         ret = make_remote(name, 0);
 272         if (name[0] != '/') {
 273                 if (!ret->uri)
 274                         read_remotes_file(ret);
 275                 if (!ret->uri)
 276                         read_branches_file(ret);
 277         }
 278         if (!ret->uri)
 279                 add_uri(ret, name);
 280         if (!ret->uri)
 281                 return NULL;
 282         ret->fetch = parse_ref_spec(ret->fetch_refspec_nr, ret->fetch_refspec);
 283         ret->push = parse_ref_spec(ret->push_refspec_nr, ret->push_refspec);
 284         return ret;
 285 }
 286
 287 int for_each_remote(each_remote_fn fn, void *priv)
 288 {
 289         int i, result = 0;
 290         read_config();
 291         for (i = 0; i < allocated_remotes && !result; i++) {
 292                 struct remote *r = remotes[i];
 293                 if (!r)
 294                         continue;
 295                 if (!r->fetch)
 296                         r->fetch = parse_ref_spec(r->fetch_refspec_nr,
 297                                         r->fetch_refspec);
 298                 if (!r->push)
 299                         r->push = parse_ref_spec(r->push_refspec_nr,
 300                                         r->push_refspec);
 301                 result = fn(r, priv);
 302         }
 303         return result;
 304 }
 305
 306 int remote_has_uri(struct remote *remote, const char *uri)
 307 {
 308         int i;
 309         for (i = 0; i < remote->uri_nr; i++) {
 310                 if (!strcmp(remote->uri[i], uri))
 311                         return 1;
 312         }
 313         return 0;
 314 }
 315
 316 int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 317 {
 318         int find_src = refspec->src == NULL;
 319         char *needle, **result;
 320         int i;
 321
 322         if (find_src) {
 323                 if (refspec->dst == NULL)
 324                         return error("find_tracking: need either src or dst");
 325                 needle = refspec->dst;
 326                 result = &refspec->src;
 327         } else {
 328                 needle = refspec->src;
 329                 result = &refspec->dst;
 330         }
 331
 332         for (i = 0; i < remote->fetch_refspec_nr; i++) {
 333                 struct refspec *fetch = &remote->fetch[i];
 334                 const char *key = find_src ? fetch->dst : fetch->src;
 335                 const char *value = find_src ? fetch->src : fetch->dst;
 336                 if (!fetch->dst)
 337                         continue;
 338                 if (fetch->pattern) {
 339                         if (!prefixcmp(needle, key)) {
 340                                 *result = xmalloc(strlen(value) +
 341                                                   strlen(needle) -
 342                                                   strlen(key) + 1);
 343                                 strcpy(*result, value);
 344                                 strcpy(*result + strlen(value),
 345                                        needle + strlen(key));
 346                                 refspec->force = fetch->force;
 347                                 return 0;
 348                         }
 349                 } else if (!strcmp(needle, key)) {
 350                         *result = xstrdup(value);
 351                         refspec->force = fetch->force;
 352                         return 0;
 353                 }
 354         }
 355         return -1;
 356 }
 357
 358 struct ref *alloc_ref(unsigned namelen)
 359 {
 360         struct ref *ret = xmalloc(sizeof(struct ref) + namelen);
 361         memset(ret, 0, sizeof(struct ref) + namelen);
 362         return ret;
 363 }
 364
 365 void free_refs(struct ref *ref)
 366 {
 367         struct ref *next;
 368         while (ref) {
 369                 next = ref->next;
 370                 if (ref->peer_ref)
 371                         free(ref->peer_ref);
 372                 free(ref);
 373                 ref = next;
 374         }
 375 }
 376
 377 static int count_refspec_match(const char *pattern,
 378                                struct ref *refs,
 379                                struct ref **matched_ref)
 380 {
 381         int patlen = strlen(pattern);
 382         struct ref *matched_weak = NULL;
 383         struct ref *matched = NULL;
 384         int weak_match = 0;
 385         int match = 0;
 386
 387         for (weak_match = match = 0; refs; refs = refs->next) {
 388                 char *name = refs->name;
 389                 int namelen = strlen(name);
 390
 391                 if (namelen < patlen ||
 392                     memcmp(name + namelen - patlen, pattern, patlen))
 393                         continue;
 394                 if (namelen != patlen && name[namelen - patlen - 1] != '/')
 395                         continue;
 396
 397                 /* A match is "weak" if it is with refs outside
 398                  * heads or tags, and did not specify the pattern
 399                  * in full (e.g. "refs/remotes/origin/master") or at
 400                  * least from the toplevel (e.g. "remotes/origin/master");
 401                  * otherwise "git push $URL master" would result in
 402                  * ambiguity between remotes/origin/master and heads/master
 403                  * at the remote site.
 404                  */
 405                 if (namelen != patlen &&
 406                     patlen != namelen - 5 &&
 407                     prefixcmp(name, "refs/heads/") &&
 408                     prefixcmp(name, "refs/tags/")) {
 409                         /* We want to catch the case where only weak
 410                          * matches are found and there are multiple
 411                          * matches, and where more than one strong
 412                          * matches are found, as ambiguous.  One
 413                          * strong match with zero or more weak matches
 414                          * are acceptable as a unique match.
 415                          */
 416                         matched_weak = refs;
 417                         weak_match++;
 418                 }
 419                 else {
 420                         matched = refs;
 421                         match++;
 422                 }
 423         }
 424         if (!matched) {
 425                 *matched_ref = matched_weak;
 426                 return weak_match;
 427         }
 428         else {
 429                 *matched_ref = matched;
 430                 return match;
 431         }
 432 }
 433
 434 static void tail_link_ref(struct ref *ref, struct ref ***tail)
 435 {
 436         **tail = ref;
 437         while (ref->next)
 438                 ref = ref->next;
 439         *tail = &ref->next;
 440 }
 441
 442 static struct ref *try_explicit_object_name(const char *name)
 443 {
 444         unsigned char sha1[20];
 445         struct ref *ref;
 446         int len;
 447
 448         if (!*name) {
 449                 ref = alloc_ref(20);
 450                 strcpy(ref->name, "(delete)");
 451                 hashclr(ref->new_sha1);
 452                 return ref;
 453         }
 454         if (get_sha1(name, sha1))
 455                 return NULL;
 456         len = strlen(name) + 1;
 457         ref = alloc_ref(len);
 458         memcpy(ref->name, name, len);
 459         hashcpy(ref->new_sha1, sha1);
 460         return ref;
 461 }
 462
 463 static struct ref *make_linked_ref(const char *name, struct ref ***tail)
 464 {
 465         struct ref *ret;
 466         size_t len;
 467
 468         len = strlen(name) + 1;
 469         ret = alloc_ref(len);
 470         memcpy(ret->name, name, len);
 471         tail_link_ref(ret, tail);
 472         return ret;
 473 }
 474
 475 static int match_explicit(struct ref *src, struct ref *dst,
 476                           struct ref ***dst_tail,
 477                           struct refspec *rs,
 478                           int errs)
 479 {
 480         struct ref *matched_src, *matched_dst;
 481
 482         const char *dst_value = rs->dst;
 483
 484         if (rs->pattern)
 485                 return errs;
 486
 487         matched_src = matched_dst = NULL;
 488         switch (count_refspec_match(rs->src, src, &matched_src)) {
 489         case 1:
 490                 break;
 491         case 0:
 492                 /* The source could be in the get_sha1() format
 493                  * not a reference name.  :refs/other is a
 494                  * way to delete 'other' ref at the remote end.
 495                  */
 496                 matched_src = try_explicit_object_name(rs->src);
 497                 if (matched_src)
 498                         break;
 499                 error("src refspec %s does not match any.",
 500                       rs->src);
 501                 break;
 502         default:
 503                 matched_src = NULL;
 504                 error("src refspec %s matches more than one.",
 505                       rs->src);
 506                 break;
 507         }
 508
 509         if (!matched_src)
 510                 errs = 1;
 511
 512         if (dst_value == NULL)
 513                 dst_value = matched_src->name;
 514
 515         switch (count_refspec_match(dst_value, dst, &matched_dst)) {
 516         case 1:
 517                 break;
 518         case 0:
 519                 if (!memcmp(dst_value, "refs/", 5))
 520                         matched_dst = make_linked_ref(dst_value, dst_tail);
 521                 else
 522                         error("dst refspec %s does not match any "
 523                               "existing ref on the remote and does "
 524                               "not start with refs/.", dst_value);
 525                 break;
 526         default:
 527                 matched_dst = NULL;
 528                 error("dst refspec %s matches more than one.",
 529                       dst_value);
 530                 break;
 531         }
 532         if (errs || matched_dst == NULL)
 533                 return 1;
 534         if (matched_dst->peer_ref) {
 535                 errs = 1;
 536                 error("dst ref %s receives from more than one src.",
 537                       matched_dst->name);
 538         }
 539         else {
 540                 matched_dst->peer_ref = matched_src;
 541                 matched_dst->force = rs->force;
 542         }
 543         return errs;
 544 }
 545
 546 static int match_explicit_refs(struct ref *src, struct ref *dst,
 547                                struct ref ***dst_tail, struct refspec *rs,
 548                                int rs_nr)
 549 {
 550         int i, errs;
 551         for (i = errs = 0; i < rs_nr; i++)
 552                 errs |= match_explicit(src, dst, dst_tail, &rs[i], errs);
 553         return -errs;
 554 }
 555
 556 static struct ref *find_ref_by_name(struct ref *list, const char *name)
 557 {
 558         for ( ; list; list = list->next)
 559                 if (!strcmp(list->name, name))
 560                         return list;
 561         return NULL;
 562 }
 563
 564 static const struct refspec *check_pattern_match(const struct refspec *rs,
 565                                                  int rs_nr,
 566                                                  const struct ref *src)
 567 {
 568         int i;
 569         for (i = 0; i < rs_nr; i++) {
 570                 if (rs[i].pattern && !prefixcmp(src->name, rs[i].src))
 571                         return rs + i;
 572         }
 573         return NULL;
 574 }
 575
 576 /*
 577  * Note. This is used only by "push"; refspec matching rules for
 578  * push and fetch are subtly different, so do not try to reuse it
 579  * without thinking.
 580  */
 581 int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 582                int nr_refspec, char **refspec, int all)
 583 {
 584         struct refspec *rs =
 585                 parse_ref_spec(nr_refspec, (const char **) refspec);
 586
 587         if (match_explicit_refs(src, dst, dst_tail, rs, nr_refspec))
 588                 return -1;
 589
 590         /* pick the remainder */
 591         for ( ; src; src = src->next) {
 592                 struct ref *dst_peer;
 593                 const struct refspec *pat = NULL;
 594                 char *dst_name;
 595                 if (src->peer_ref)
 596                         continue;
 597                 if (nr_refspec) {
 598                         pat = check_pattern_match(rs, nr_refspec, src);
 599                         if (!pat)
 600                                 continue;
 601                 }
 602                 else if (prefixcmp(src->name, "refs/heads/"))
 603                         /*
 604                          * "matching refs"; traditionally we pushed everything
 605                          * including refs outside refs/heads/ hierarchy, but
 606                          * that does not make much sense these days.
 607                          */
 608                         continue;
 609
 610                 if (pat) {
 611                         const char *dst_side = pat->dst ? pat->dst : pat->src;
 612                         dst_name = xmalloc(strlen(dst_side) +
 613                                            strlen(src->name) -
 614                                            strlen(pat->src) + 2);
 615                         strcpy(dst_name, dst_side);
 616                         strcat(dst_name, src->name + strlen(pat->src));
 617                 } else
 618                         dst_name = xstrdup(src->name);
 619                 dst_peer = find_ref_by_name(dst, dst_name);
 620                 if (dst_peer && dst_peer->peer_ref)
 621                         /* We're already sending something to this ref. */
 622                         goto free_name;
 623                 if (!dst_peer && !nr_refspec && !all)
 624                         /* Remote doesn't have it, and we have no
 625                          * explicit pattern, and we don't have
 626                          * --all. */
 627                         goto free_name;
 628                 if (!dst_peer) {
 629                         /* Create a new one and link it */
 630                         dst_peer = make_linked_ref(dst_name, dst_tail);
 631                         hashcpy(dst_peer->new_sha1, src->new_sha1);
 632                 }
 633                 dst_peer->peer_ref = src;
 634         free_name:
 635                 free(dst_name);
 636         }
 637         return 0;
 638 }