send-pack.c

   1 #include "cache.h"
   2 #include "commit.h"
   3 #include "tag.h"
   4 #include "refs.h"
   5 #include "pkt-line.h"
   6 #include "run-command.h"
   7
   8 static const char send_pack_usage[] =
   9 "git-send-pack [--all] [--force] [--receive-pack=<git-receive-pack>] [--verbose] [--thin] [<host>:]<directory> [<ref>...]\n"
  10 "  --all and explicit <ref> specification are mutually exclusive.";
  11 static const char *receivepack = "git-receive-pack";
  12 static int verbose;
  13 static int send_all;
  14 static int force_update;
  15 static int use_thin_pack;
  16
  17 /*
  18  * Make a pack stream and spit it out into file descriptor fd
  19  */
  20 static int pack_objects(int fd, struct ref *refs)
  21 {
  22         /*
  23          * The child becomes pack-objects --revs; we feed
  24          * the revision parameters to it via its stdin and
  25          * let its stdout go back to the other end.
  26          */
  27         const char *args[] = {
  28                 "pack-objects",
  29                 "--all-progress",
  30                 "--revs",
  31                 "--stdout",
  32                 NULL,
  33                 NULL,
  34         };
  35         struct child_process po;
  36
  37         if (use_thin_pack)
  38                 args[4] = "--thin";
  39         memset(&po, 0, sizeof(po));
  40         po.argv = args;
  41         po.in = -1;
  42         po.out = fd;
  43         po.git_cmd = 1;
  44         if (start_command(&po))
  45                 die("git-pack-objects failed (%s)", strerror(errno));
  46
  47         /*
  48          * We feed the pack-objects we just spawned with revision
  49          * parameters by writing to the pipe.
  50          */
  51         while (refs) {
  52                 char buf[42];
  53
  54                 if (!is_null_sha1(refs->old_sha1) &&
  55                     has_sha1_file(refs->old_sha1)) {
  56                         memcpy(buf + 1, sha1_to_hex(refs->old_sha1), 40);
  57                         buf[0] = '^';
  58                         buf[41] = '\n';
  59                         if (!write_or_whine(po.in, buf, 42,
  60                                                 "send-pack: send refs"))
  61                                 break;
  62                 }
  63                 if (!is_null_sha1(refs->new_sha1)) {
  64                         memcpy(buf, sha1_to_hex(refs->new_sha1), 40);
  65                         buf[40] = '\n';
  66                         if (!write_or_whine(po.in, buf, 41,
  67                                                 "send-pack: send refs"))
  68                                 break;
  69                 }
  70                 refs = refs->next;
  71         }
  72
  73         if (finish_command(&po))
  74                 return error("pack-objects died with strange error");
  75         return 0;
  76 }
  77
  78 static void unmark_and_free(struct commit_list *list, unsigned int mark)
  79 {
  80         while (list) {
  81                 struct commit_list *temp = list;
  82                 temp->item->object.flags &= ~mark;
  83                 list = temp->next;
  84                 free(temp);
  85         }
  86 }
  87
  88 static int ref_newer(const unsigned char *new_sha1,
  89                      const unsigned char *old_sha1)
  90 {
  91         struct object *o;
  92         struct commit *old, *new;
  93         struct commit_list *list, *used;
  94         int found = 0;
  95
  96         /* Both new and old must be commit-ish and new is descendant of
  97          * old.  Otherwise we require --force.
  98          */
  99         o = deref_tag(parse_object(old_sha1), NULL, 0);
 100         if (!o || o->type != OBJ_COMMIT)
 101                 return 0;
 102         old = (struct commit *) o;
 103
 104         o = deref_tag(parse_object(new_sha1), NULL, 0);
 105         if (!o || o->type != OBJ_COMMIT)
 106                 return 0;
 107         new = (struct commit *) o;
 108
 109         if (parse_commit(new) < 0)
 110                 return 0;
 111
 112         used = list = NULL;
 113         commit_list_insert(new, &list);
 114         while (list) {
 115                 new = pop_most_recent_commit(&list, 1);
 116                 commit_list_insert(new, &used);
 117                 if (new == old) {
 118                         found = 1;
 119                         break;
 120                 }
 121         }
 122         unmark_and_free(list, 1);
 123         unmark_and_free(used, 1);
 124         return found;
 125 }
 126
 127 static struct ref *local_refs, **local_tail;
 128 static struct ref *remote_refs, **remote_tail;
 129
 130 static int one_local_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 131 {
 132         struct ref *ref;
 133         int len = strlen(refname) + 1;
 134         ref = xcalloc(1, sizeof(*ref) + len);
 135         hashcpy(ref->new_sha1, sha1);
 136         memcpy(ref->name, refname, len);
 137         *local_tail = ref;
 138         local_tail = &ref->next;
 139         return 0;
 140 }
 141
 142 static void get_local_heads(void)
 143 {
 144         local_tail = &local_refs;
 145         for_each_ref(one_local_ref, NULL);
 146 }
 147
 148 static int receive_status(int in)
 149 {
 150         char line[1000];
 151         int ret = 0;
 152         int len = packet_read_line(in, line, sizeof(line));
 153         if (len < 10 || memcmp(line, "unpack ", 7)) {
 154                 fprintf(stderr, "did not receive status back\n");
 155                 return -1;
 156         }
 157         if (memcmp(line, "unpack ok\n", 10)) {
 158                 fputs(line, stderr);
 159                 ret = -1;
 160         }
 161         while (1) {
 162                 len = packet_read_line(in, line, sizeof(line));
 163                 if (!len)
 164                         break;
 165                 if (len < 3 ||
 166                     (memcmp(line, "ok", 2) && memcmp(line, "ng", 2))) {
 167                         fprintf(stderr, "protocol error: %s\n", line);
 168                         ret = -1;
 169                         break;
 170                 }
 171                 if (!memcmp(line, "ok", 2))
 172                         continue;
 173                 fputs(line, stderr);
 174                 ret = -1;
 175         }
 176         return ret;
 177 }
 178
 179 static int send_pack(int in, int out, int nr_refspec, char **refspec)
 180 {
 181         struct ref *ref;
 182         int new_refs;
 183         int ret = 0;
 184         int ask_for_status_report = 0;
 185         int allow_deleting_refs = 0;
 186         int expect_status_report = 0;
 187
 188         /* No funny business with the matcher */
 189         remote_tail = get_remote_heads(in, &remote_refs, 0, NULL, REF_NORMAL);
 190         get_local_heads();
 191
 192         /* Does the other end support the reporting? */
 193         if (server_supports("report-status"))
 194                 ask_for_status_report = 1;
 195         if (server_supports("delete-refs"))
 196                 allow_deleting_refs = 1;
 197
 198         /* match them up */
 199         if (!remote_tail)
 200                 remote_tail = &remote_refs;
 201         if (match_refs(local_refs, remote_refs, &remote_tail,
 202                        nr_refspec, refspec, send_all))
 203                 return -1;
 204
 205         if (!remote_refs) {
 206                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n");
 207                 return 0;
 208         }
 209
 210         /*
 211          * Finally, tell the other end!
 212          */
 213         new_refs = 0;
 214         for (ref = remote_refs; ref; ref = ref->next) {
 215                 char old_hex[60], *new_hex;
 216                 int delete_ref;
 217
 218                 if (!ref->peer_ref)
 219                         continue;
 220
 221                 delete_ref = is_null_sha1(ref->peer_ref->new_sha1);
 222                 if (delete_ref && !allow_deleting_refs) {
 223                         error("remote does not support deleting refs");
 224                         ret = -2;
 225                         continue;
 226                 }
 227                 if (!delete_ref &&
 228                     !hashcmp(ref->old_sha1, ref->peer_ref->new_sha1)) {
 229                         if (verbose)
 230                                 fprintf(stderr, "'%s': up-to-date\n", ref->name);
 231                         continue;
 232                 }
 233
 234                 /* This part determines what can overwrite what.
 235                  * The rules are:
 236                  *
 237                  * (0) you can always use --force or +A:B notation to
 238                  *     selectively force individual ref pairs.
 239                  *
 240                  * (1) if the old thing does not exist, it is OK.
 241                  *
 242                  * (2) if you do not have the old thing, you are not allowed
 243                  *     to overwrite it; you would not know what you are losing
 244                  *     otherwise.
 245                  *
 246                  * (3) if both new and old are commit-ish, and new is a
 247                  *     descendant of old, it is OK.
 248                  *
 249                  * (4) regardless of all of the above, removing :B is
 250                  *     always allowed.
 251                  */
 252
 253                 if (!force_update &&
 254                     !delete_ref &&
 255                     !is_null_sha1(ref->old_sha1) &&
 256                     !ref->force) {
 257                         if (!has_sha1_file(ref->old_sha1) ||
 258                             !ref_newer(ref->peer_ref->new_sha1,
 259                                        ref->old_sha1)) {
 260                                 /* We do not have the remote ref, or
 261                                  * we know that the remote ref is not
 262                                  * an ancestor of what we are trying to
 263                                  * push.  Either way this can be losing
 264                                  * commits at the remote end and likely
 265                                  * we were not up to date to begin with.
 266                                  */
 267                                 error("remote '%s' is not a strict "
 268                                       "subset of local ref '%s'. "
 269                                       "maybe you are not up-to-date and "
 270                                       "need to pull first?",
 271                                       ref->name,
 272                                       ref->peer_ref->name);
 273                                 ret = -2;
 274                                 continue;
 275                         }
 276                 }
 277                 hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
 278                 if (!delete_ref)
 279                         new_refs++;
 280                 strcpy(old_hex, sha1_to_hex(ref->old_sha1));
 281                 new_hex = sha1_to_hex(ref->new_sha1);
 282
 283                 if (ask_for_status_report) {
 284                         packet_write(out, "%s %s %s%c%s",
 285                                      old_hex, new_hex, ref->name, 0,
 286                                      "report-status");
 287                         ask_for_status_report = 0;
 288                         expect_status_report = 1;
 289                 }
 290                 else
 291                         packet_write(out, "%s %s %s",
 292                                      old_hex, new_hex, ref->name);
 293                 if (delete_ref)
 294                         fprintf(stderr, "deleting '%s'\n", ref->name);
 295                 else {
 296                         fprintf(stderr, "updating '%s'", ref->name);
 297                         if (strcmp(ref->name, ref->peer_ref->name))
 298                                 fprintf(stderr, " using '%s'",
 299                                         ref->peer_ref->name);
 300                         fprintf(stderr, "\n  from %s\n  to   %s\n",
 301                                 old_hex, new_hex);
 302                 }
 303         }
 304
 305         packet_flush(out);
 306         if (new_refs)
 307                 ret = pack_objects(out, remote_refs);
 308         close(out);
 309
 310         if (expect_status_report) {
 311                 if (receive_status(in))
 312                         ret = -4;
 313         }
 314
 315         if (!new_refs && ret == 0)
 316                 fprintf(stderr, "Everything up-to-date\n");
 317         return ret;
 318 }
 319
 320 static void verify_remote_names(int nr_heads, char **heads)
 321 {
 322         int i;
 323
 324         for (i = 0; i < nr_heads; i++) {
 325                 const char *remote = strchr(heads[i], ':');
 326
 327                 remote = remote ? (remote + 1) : heads[i];
 328                 switch (check_ref_format(remote)) {
 329                 case 0: /* ok */
 330                 case -2: /* ok but a single level -- that is fine for
 331                           * a match pattern.
 332                           */
 333                         continue;
 334                 }
 335                 die("remote part of refspec is not a valid name in %s",
 336                     heads[i]);
 337         }
 338 }
 339
 340 int main(int argc, char **argv)
 341 {
 342         int i, nr_heads = 0;
 343         char *dest = NULL;
 344         char **heads = NULL;
 345         int fd[2], ret;
 346         pid_t pid;
 347
 348         setup_git_directory();
 349         git_config(git_default_config);
 350
 351         argv++;
 352         for (i = 1; i < argc; i++, argv++) {
 353                 char *arg = *argv;
 354
 355                 if (*arg == '-') {
 356                         if (!prefixcmp(arg, "--receive-pack=")) {
 357                                 receivepack = arg + 15;
 358                                 continue;
 359                         }
 360                         if (!prefixcmp(arg, "--exec=")) {
 361                                 receivepack = arg + 7;
 362                                 continue;
 363                         }
 364                         if (!strcmp(arg, "--all")) {
 365                                 send_all = 1;
 366                                 continue;
 367                         }
 368                         if (!strcmp(arg, "--force")) {
 369                                 force_update = 1;
 370                                 continue;
 371                         }
 372                         if (!strcmp(arg, "--verbose")) {
 373                                 verbose = 1;
 374                                 continue;
 375                         }
 376                         if (!strcmp(arg, "--thin")) {
 377                                 use_thin_pack = 1;
 378                                 continue;
 379                         }
 380                         usage(send_pack_usage);
 381                 }
 382                 if (!dest) {
 383                         dest = arg;
 384                         continue;
 385                 }
 386                 heads = argv;
 387                 nr_heads = argc - i;
 388                 break;
 389         }
 390         if (!dest)
 391                 usage(send_pack_usage);
 392         if (heads && send_all)
 393                 usage(send_pack_usage);
 394         verify_remote_names(nr_heads, heads);
 395
 396         pid = git_connect(fd, dest, receivepack, verbose ? CONNECT_VERBOSE : 0);
 397         if (pid < 0)
 398                 return 1;
 399         ret = send_pack(fd[0], fd[1], nr_heads, heads);
 400         close(fd[0]);
 401         close(fd[1]);
 402         ret |= finish_connect(pid);
 403         return !!ret;
 404 }