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         }
 200         return 0;
 201 }
 202
 203 static void read_config(void)
 204 {
 205         unsigned char sha1[20];
 206         const char *head_ref;
 207         int flag;
 208         if (default_remote_name) // did this already
 209                 return;
 210         default_remote_name = xstrdup("origin");
 211         current_branch = NULL;
 212         head_ref = resolve_ref("HEAD", sha1, 0, &flag);
 213         if (head_ref && (flag & REF_ISSYMREF) &&
 214             !prefixcmp(head_ref, "refs/heads/")) {
 215                 current_branch = head_ref + strlen("refs/heads/");
 216                 current_branch_len = strlen(current_branch);
 217         }
 218         git_config(handle_config);
 219 }
 220
 221 static struct refspec *parse_ref_spec(int nr_refspec, const char **refspec)
 222 {
 223         int i;
 224         struct refspec *rs = xcalloc(sizeof(*rs), nr_refspec);
 225         for (i = 0; i < nr_refspec; i++) {
 226                 const char *sp, *ep, *gp;
 227                 sp = refspec[i];
 228                 if (*sp == '+') {
 229                         rs[i].force = 1;
 230                         sp++;
 231                 }
 232                 gp = strchr(sp, '*');
 233                 ep = strchr(sp, ':');
 234                 if (gp && ep && gp > ep)
 235                         gp = NULL;
 236                 if (ep) {
 237                         if (ep[1]) {
 238                                 const char *glob = strchr(ep + 1, '*');
 239                                 if (!glob)
 240                                         gp = NULL;
 241                                 if (gp)
 242                                         rs[i].dst = xstrndup(ep + 1,
 243                                                              glob - ep - 1);
 244                                 else
 245                                         rs[i].dst = xstrdup(ep + 1);
 246                         }
 247                 } else {
 248                         ep = sp + strlen(sp);
 249                 }
 250                 if (gp) {
 251                         rs[i].pattern = 1;
 252                         ep = gp;
 253                 }
 254                 rs[i].src = xstrndup(sp, ep - sp);
 255         }
 256         return rs;
 257 }
 258
 259 struct remote *remote_get(const char *name)
 260 {
 261         struct remote *ret;
 262
 263         read_config();
 264         if (!name)
 265                 name = default_remote_name;
 266         ret = make_remote(name, 0);
 267         if (name[0] != '/') {
 268                 if (!ret->uri)
 269                         read_remotes_file(ret);
 270                 if (!ret->uri)
 271                         read_branches_file(ret);
 272         }
 273         if (!ret->uri)
 274                 add_uri(ret, name);
 275         if (!ret->uri)
 276                 return NULL;
 277         ret->fetch = parse_ref_spec(ret->fetch_refspec_nr, ret->fetch_refspec);
 278         ret->push = parse_ref_spec(ret->push_refspec_nr, ret->push_refspec);
 279         return ret;
 280 }
 281
 282 int for_each_remote(each_remote_fn fn, void *priv)
 283 {
 284         int i, result = 0;
 285         read_config();
 286         for (i = 0; i < allocated_remotes && !result; i++) {
 287                 struct remote *r = remotes[i];
 288                 if (!r)
 289                         continue;
 290                 if (!r->fetch)
 291                         r->fetch = parse_ref_spec(r->fetch_refspec_nr,
 292                                         r->fetch_refspec);
 293                 if (!r->push)
 294                         r->push = parse_ref_spec(r->push_refspec_nr,
 295                                         r->push_refspec);
 296                 result = fn(r, priv);
 297         }
 298         return result;
 299 }
 300
 301 int remote_has_uri(struct remote *remote, const char *uri)
 302 {
 303         int i;
 304         for (i = 0; i < remote->uri_nr; i++) {
 305                 if (!strcmp(remote->uri[i], uri))
 306                         return 1;
 307         }
 308         return 0;
 309 }
 310
 311 int remote_find_tracking(struct remote *remote, struct refspec *refspec)
 312 {
 313         int find_src = refspec->src == NULL;
 314         char *needle, **result;
 315         int i;
 316
 317         if (find_src) {
 318                 if (refspec->dst == NULL)
 319                         return error("find_tracking: need either src or dst");
 320                 needle = refspec->dst;
 321                 result = &refspec->src;
 322         } else {
 323                 needle = refspec->src;
 324                 result = &refspec->dst;
 325         }
 326
 327         for (i = 0; i < remote->fetch_refspec_nr; i++) {
 328                 struct refspec *fetch = &remote->fetch[i];
 329                 const char *key = find_src ? fetch->dst : fetch->src;
 330                 const char *value = find_src ? fetch->src : fetch->dst;
 331                 if (!fetch->dst)
 332                         continue;
 333                 if (fetch->pattern) {
 334                         if (!prefixcmp(needle, key)) {
 335                                 *result = xmalloc(strlen(value) +
 336                                                   strlen(needle) -
 337                                                   strlen(key) + 1);
 338                                 strcpy(*result, value);
 339                                 strcpy(*result + strlen(value),
 340                                        needle + strlen(key));
 341                                 refspec->force = fetch->force;
 342                                 return 0;
 343                         }
 344                 } else if (!strcmp(needle, key)) {
 345                         *result = xstrdup(value);
 346                         refspec->force = fetch->force;
 347                         return 0;
 348                 }
 349         }
 350         return -1;
 351 }
 352
 353 struct ref *alloc_ref(unsigned namelen)
 354 {
 355         struct ref *ret = xmalloc(sizeof(struct ref) + namelen);
 356         memset(ret, 0, sizeof(struct ref) + namelen);
 357         return ret;
 358 }
 359
 360 void free_refs(struct ref *ref)
 361 {
 362         struct ref *next;
 363         while (ref) {
 364                 next = ref->next;
 365                 if (ref->peer_ref)
 366                         free(ref->peer_ref);
 367                 free(ref);
 368                 ref = next;
 369         }
 370 }
 371
 372 static int count_refspec_match(const char *pattern,
 373                                struct ref *refs,
 374                                struct ref **matched_ref)
 375 {
 376         int patlen = strlen(pattern);
 377         struct ref *matched_weak = NULL;
 378         struct ref *matched = NULL;
 379         int weak_match = 0;
 380         int match = 0;
 381
 382         for (weak_match = match = 0; refs; refs = refs->next) {
 383                 char *name = refs->name;
 384                 int namelen = strlen(name);
 385
 386                 if (namelen < patlen ||
 387                     memcmp(name + namelen - patlen, pattern, patlen))
 388                         continue;
 389                 if (namelen != patlen && name[namelen - patlen - 1] != '/')
 390                         continue;
 391
 392                 /* A match is "weak" if it is with refs outside
 393                  * heads or tags, and did not specify the pattern
 394                  * in full (e.g. "refs/remotes/origin/master") or at
 395                  * least from the toplevel (e.g. "remotes/origin/master");
 396                  * otherwise "git push $URL master" would result in
 397                  * ambiguity between remotes/origin/master and heads/master
 398                  * at the remote site.
 399                  */
 400                 if (namelen != patlen &&
 401                     patlen != namelen - 5 &&
 402                     prefixcmp(name, "refs/heads/") &&
 403                     prefixcmp(name, "refs/tags/")) {
 404                         /* We want to catch the case where only weak
 405                          * matches are found and there are multiple
 406                          * matches, and where more than one strong
 407                          * matches are found, as ambiguous.  One
 408                          * strong match with zero or more weak matches
 409                          * are acceptable as a unique match.
 410                          */
 411                         matched_weak = refs;
 412                         weak_match++;
 413                 }
 414                 else {
 415                         matched = refs;
 416                         match++;
 417                 }
 418         }
 419         if (!matched) {
 420                 *matched_ref = matched_weak;
 421                 return weak_match;
 422         }
 423         else {
 424                 *matched_ref = matched;
 425                 return match;
 426         }
 427 }
 428
 429 static void tail_link_ref(struct ref *ref, struct ref ***tail)
 430 {
 431         **tail = ref;
 432         while (ref->next)
 433                 ref = ref->next;
 434         *tail = &ref->next;
 435 }
 436
 437 static struct ref *try_explicit_object_name(const char *name)
 438 {
 439         unsigned char sha1[20];
 440         struct ref *ref;
 441         int len;
 442
 443         if (!*name) {
 444                 ref = alloc_ref(20);
 445                 strcpy(ref->name, "(delete)");
 446                 hashclr(ref->new_sha1);
 447                 return ref;
 448         }
 449         if (get_sha1(name, sha1))
 450                 return NULL;
 451         len = strlen(name) + 1;
 452         ref = alloc_ref(len);
 453         memcpy(ref->name, name, len);
 454         hashcpy(ref->new_sha1, sha1);
 455         return ref;
 456 }
 457
 458 static struct ref *make_linked_ref(const char *name, struct ref ***tail)
 459 {
 460         struct ref *ret;
 461         size_t len;
 462
 463         len = strlen(name) + 1;
 464         ret = alloc_ref(len);
 465         memcpy(ret->name, name, len);
 466         tail_link_ref(ret, tail);
 467         return ret;
 468 }
 469
 470 static int match_explicit(struct ref *src, struct ref *dst,
 471                           struct ref ***dst_tail,
 472                           struct refspec *rs,
 473                           int errs)
 474 {
 475         struct ref *matched_src, *matched_dst;
 476
 477         const char *dst_value = rs->dst;
 478
 479         if (rs->pattern)
 480                 return errs;
 481
 482         matched_src = matched_dst = NULL;
 483         switch (count_refspec_match(rs->src, src, &matched_src)) {
 484         case 1:
 485                 break;
 486         case 0:
 487                 /* The source could be in the get_sha1() format
 488                  * not a reference name.  :refs/other is a
 489                  * way to delete 'other' ref at the remote end.
 490                  */
 491                 matched_src = try_explicit_object_name(rs->src);
 492                 if (matched_src)
 493                         break;
 494                 error("src refspec %s does not match any.",
 495                       rs->src);
 496                 break;
 497         default:
 498                 matched_src = NULL;
 499                 error("src refspec %s matches more than one.",
 500                       rs->src);
 501                 break;
 502         }
 503
 504         if (!matched_src)
 505                 errs = 1;
 506
 507         if (!dst_value) {
 508                 if (!matched_src)
 509                         return errs;
 510                 dst_value = matched_src->name;
 511         }
 512
 513         switch (count_refspec_match(dst_value, dst, &matched_dst)) {
 514         case 1:
 515                 break;
 516         case 0:
 517                 if (!memcmp(dst_value, "refs/", 5))
 518                         matched_dst = make_linked_ref(dst_value, dst_tail);
 519                 else
 520                         error("dst refspec %s does not match any "
 521                               "existing ref on the remote and does "
 522                               "not start with refs/.", dst_value);
 523                 break;
 524         default:
 525                 matched_dst = NULL;
 526                 error("dst refspec %s matches more than one.",
 527                       dst_value);
 528                 break;
 529         }
 530         if (errs || matched_dst == NULL)
 531                 return 1;
 532         if (matched_dst->peer_ref) {
 533                 errs = 1;
 534                 error("dst ref %s receives from more than one src.",
 535                       matched_dst->name);
 536         }
 537         else {
 538                 matched_dst->peer_ref = matched_src;
 539                 matched_dst->force = rs->force;
 540         }
 541         return errs;
 542 }
 543
 544 static int match_explicit_refs(struct ref *src, struct ref *dst,
 545                                struct ref ***dst_tail, struct refspec *rs,
 546                                int rs_nr)
 547 {
 548         int i, errs;
 549         for (i = errs = 0; i < rs_nr; i++)
 550                 errs |= match_explicit(src, dst, dst_tail, &rs[i], errs);
 551         return -errs;
 552 }
 553
 554 static struct ref *find_ref_by_name(struct ref *list, const char *name)
 555 {
 556         for ( ; list; list = list->next)
 557                 if (!strcmp(list->name, name))
 558                         return list;
 559         return NULL;
 560 }
 561
 562 static const struct refspec *check_pattern_match(const struct refspec *rs,
 563                                                  int rs_nr,
 564                                                  const struct ref *src)
 565 {
 566         int i;
 567         for (i = 0; i < rs_nr; i++) {
 568                 if (rs[i].pattern && !prefixcmp(src->name, rs[i].src))
 569                         return rs + i;
 570         }
 571         return NULL;
 572 }
 573
 574 /*
 575  * Note. This is used only by "push"; refspec matching rules for
 576  * push and fetch are subtly different, so do not try to reuse it
 577  * without thinking.
 578  */
 579 int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
 580                int nr_refspec, char **refspec, int all)
 581 {
 582         struct refspec *rs =
 583                 parse_ref_spec(nr_refspec, (const char **) refspec);
 584
 585         if (match_explicit_refs(src, dst, dst_tail, rs, nr_refspec))
 586                 return -1;
 587
 588         /* pick the remainder */
 589         for ( ; src; src = src->next) {
 590                 struct ref *dst_peer;
 591                 const struct refspec *pat = NULL;
 592                 char *dst_name;
 593                 if (src->peer_ref)
 594                         continue;
 595                 if (nr_refspec) {
 596                         pat = check_pattern_match(rs, nr_refspec, src);
 597                         if (!pat)
 598                                 continue;
 599                 }
 600                 else if (prefixcmp(src->name, "refs/heads/"))
 601                         /*
 602                          * "matching refs"; traditionally we pushed everything
 603                          * including refs outside refs/heads/ hierarchy, but
 604                          * that does not make much sense these days.
 605                          */
 606                         continue;
 607
 608                 if (pat) {
 609                         const char *dst_side = pat->dst ? pat->dst : pat->src;
 610                         dst_name = xmalloc(strlen(dst_side) +
 611                                            strlen(src->name) -
 612                                            strlen(pat->src) + 2);
 613                         strcpy(dst_name, dst_side);
 614                         strcat(dst_name, src->name + strlen(pat->src));
 615                 } else
 616                         dst_name = xstrdup(src->name);
 617                 dst_peer = find_ref_by_name(dst, dst_name);
 618                 if (dst_peer && dst_peer->peer_ref)
 619                         /* We're already sending something to this ref. */
 620                         goto free_name;
 621                 if (!dst_peer && !nr_refspec && !all)
 622                         /* Remote doesn't have it, and we have no
 623                          * explicit pattern, and we don't have
 624                          * --all. */
 625                         goto free_name;
 626                 if (!dst_peer) {
 627                         /* Create a new one and link it */
 628                         dst_peer = make_linked_ref(dst_name, dst_tail);
 629                         hashcpy(dst_peer->new_sha1, src->new_sha1);
 630                 }
 631                 dst_peer->peer_ref = src;
 632                 if (pat)
 633                         dst_peer->force = pat->force;
 634         free_name:
 635                 free(dst_name);
 636         }
 637         return 0;
 638 }