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 #include "remote.h"
   8
   9 static const char send_pack_usage[] =
  10 "git-send-pack [--all] [--force] [--receive-pack=<git-receive-pack>] [--verbose] [--thin] [<host>:]<directory> [<ref>...]\n"
  11 "  --all and explicit <ref> specification are mutually exclusive.";
  12 static const char *receivepack = "git-receive-pack";
  13 static int verbose;
  14 static int send_all;
  15 static int force_update;
  16 static int use_thin_pack;
  17
  18 /*
  19  * Make a pack stream and spit it out into file descriptor fd
  20  */
  21 static int pack_objects(int fd, struct ref *refs)
  22 {
  23         /*
  24          * The child becomes pack-objects --revs; we feed
  25          * the revision parameters to it via its stdin and
  26          * let its stdout go back to the other end.
  27          */
  28         const char *args[] = {
  29                 "pack-objects",
  30                 "--all-progress",
  31                 "--revs",
  32                 "--stdout",
  33                 NULL,
  34                 NULL,
  35         };
  36         struct child_process po;
  37
  38         if (use_thin_pack)
  39                 args[4] = "--thin";
  40         memset(&po, 0, sizeof(po));
  41         po.argv = args;
  42         po.in = -1;
  43         po.out = fd;
  44         po.git_cmd = 1;
  45         if (start_command(&po))
  46                 die("git-pack-objects failed (%s)", strerror(errno));
  47
  48         /*
  49          * We feed the pack-objects we just spawned with revision
  50          * parameters by writing to the pipe.
  51          */
  52         while (refs) {
  53                 char buf[42];
  54
  55                 if (!is_null_sha1(refs->old_sha1) &&
  56                     has_sha1_file(refs->old_sha1)) {
  57                         memcpy(buf + 1, sha1_to_hex(refs->old_sha1), 40);
  58                         buf[0] = '^';
  59                         buf[41] = '\n';
  60                         if (!write_or_whine(po.in, buf, 42,
  61                                                 "send-pack: send refs"))
  62                                 break;
  63                 }
  64                 if (!is_null_sha1(refs->new_sha1)) {
  65                         memcpy(buf, sha1_to_hex(refs->new_sha1), 40);
  66                         buf[40] = '\n';
  67                         if (!write_or_whine(po.in, buf, 41,
  68                                                 "send-pack: send refs"))
  69                                 break;
  70                 }
  71                 refs = refs->next;
  72         }
  73
  74         if (finish_command(&po))
  75                 return error("pack-objects died with strange error");
  76         return 0;
  77 }
  78
  79 static void unmark_and_free(struct commit_list *list, unsigned int mark)
  80 {
  81         while (list) {
  82                 struct commit_list *temp = list;
  83                 temp->item->object.flags &= ~mark;
  84                 list = temp->next;
  85                 free(temp);
  86         }
  87 }
  88
  89 static int ref_newer(const unsigned char *new_sha1,
  90                      const unsigned char *old_sha1)
  91 {
  92         struct object *o;
  93         struct commit *old, *new;
  94         struct commit_list *list, *used;
  95         int found = 0;
  96
  97         /* Both new and old must be commit-ish and new is descendant of
  98          * old.  Otherwise we require --force.
  99          */
 100         o = deref_tag(parse_object(old_sha1), NULL, 0);
 101         if (!o || o->type != OBJ_COMMIT)
 102                 return 0;
 103         old = (struct commit *) o;
 104
 105         o = deref_tag(parse_object(new_sha1), NULL, 0);
 106         if (!o || o->type != OBJ_COMMIT)
 107                 return 0;
 108         new = (struct commit *) o;
 109
 110         if (parse_commit(new) < 0)
 111                 return 0;
 112
 113         used = list = NULL;
 114         commit_list_insert(new, &list);
 115         while (list) {
 116                 new = pop_most_recent_commit(&list, 1);
 117                 commit_list_insert(new, &used);
 118                 if (new == old) {
 119                         found = 1;
 120                         break;
 121                 }
 122         }
 123         unmark_and_free(list, 1);
 124         unmark_and_free(used, 1);
 125         return found;
 126 }
 127
 128 static struct ref *local_refs, **local_tail;
 129 static struct ref *remote_refs, **remote_tail;
 130
 131 static int one_local_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 132 {
 133         struct ref *ref;
 134         int len = strlen(refname) + 1;
 135         ref = xcalloc(1, sizeof(*ref) + len);
 136         hashcpy(ref->new_sha1, sha1);
 137         memcpy(ref->name, refname, len);
 138         *local_tail = ref;
 139         local_tail = &ref->next;
 140         return 0;
 141 }
 142
 143 static void get_local_heads(void)
 144 {
 145         local_tail = &local_refs;
 146         for_each_ref(one_local_ref, NULL);
 147 }
 148
 149 static int receive_status(int in)
 150 {
 151         char line[1000];
 152         int ret = 0;
 153         int len = packet_read_line(in, line, sizeof(line));
 154         if (len < 10 || memcmp(line, "unpack ", 7)) {
 155                 fprintf(stderr, "did not receive status back\n");
 156                 return -1;
 157         }
 158         if (memcmp(line, "unpack ok\n", 10)) {
 159                 fputs(line, stderr);
 160                 ret = -1;
 161         }
 162         while (1) {
 163                 len = packet_read_line(in, line, sizeof(line));
 164                 if (!len)
 165                         break;
 166                 if (len < 3 ||
 167                     (memcmp(line, "ok", 2) && memcmp(line, "ng", 2))) {
 168                         fprintf(stderr, "protocol error: %s\n", line);
 169                         ret = -1;
 170                         break;
 171                 }
 172                 if (!memcmp(line, "ok", 2))
 173                         continue;
 174                 fputs(line, stderr);
 175                 ret = -1;
 176         }
 177         return ret;
 178 }
 179
 180 static int send_pack(int in, int out, int nr_refspec, char **refspec)
 181 {
 182         struct ref *ref;
 183         int new_refs;
 184         int ret = 0;
 185         int ask_for_status_report = 0;
 186         int allow_deleting_refs = 0;
 187         int expect_status_report = 0;
 188
 189         /* No funny business with the matcher */
 190         remote_tail = get_remote_heads(in, &remote_refs, 0, NULL, REF_NORMAL);
 191         get_local_heads();
 192
 193         /* Does the other end support the reporting? */
 194         if (server_supports("report-status"))
 195                 ask_for_status_report = 1;
 196         if (server_supports("delete-refs"))
 197                 allow_deleting_refs = 1;
 198
 199         /* match them up */
 200         if (!remote_tail)
 201                 remote_tail = &remote_refs;
 202         if (match_refs(local_refs, remote_refs, &remote_tail,
 203                        nr_refspec, refspec, send_all))
 204                 return -1;
 205
 206         if (!remote_refs) {
 207                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n");
 208                 return 0;
 209         }
 210
 211         /*
 212          * Finally, tell the other end!
 213          */
 214         new_refs = 0;
 215         for (ref = remote_refs; ref; ref = ref->next) {
 216                 char old_hex[60], *new_hex;
 217                 int delete_ref;
 218
 219                 if (!ref->peer_ref)
 220                         continue;
 221
 222                 delete_ref = is_null_sha1(ref->peer_ref->new_sha1);
 223                 if (delete_ref && !allow_deleting_refs) {
 224                         error("remote does not support deleting refs");
 225                         ret = -2;
 226                         continue;
 227                 }
 228                 if (!delete_ref &&
 229                     !hashcmp(ref->old_sha1, ref->peer_ref->new_sha1)) {
 230                         if (verbose)
 231                                 fprintf(stderr, "'%s': up-to-date\n", ref->name);
 232                         continue;
 233                 }
 234
 235                 /* This part determines what can overwrite what.
 236                  * The rules are:
 237                  *
 238                  * (0) you can always use --force or +A:B notation to
 239                  *     selectively force individual ref pairs.
 240                  *
 241                  * (1) if the old thing does not exist, it is OK.
 242                  *
 243                  * (2) if you do not have the old thing, you are not allowed
 244                  *     to overwrite it; you would not know what you are losing
 245                  *     otherwise.
 246                  *
 247                  * (3) if both new and old are commit-ish, and new is a
 248                  *     descendant of old, it is OK.
 249                  *
 250                  * (4) regardless of all of the above, removing :B is
 251                  *     always allowed.
 252                  */
 253
 254                 if (!force_update &&
 255                     !delete_ref &&
 256                     !is_null_sha1(ref->old_sha1) &&
 257                     !ref->force) {
 258                         if (!has_sha1_file(ref->old_sha1) ||
 259                             !ref_newer(ref->peer_ref->new_sha1,
 260                                        ref->old_sha1)) {
 261                                 /* We do not have the remote ref, or
 262                                  * we know that the remote ref is not
 263                                  * an ancestor of what we are trying to
 264                                  * push.  Either way this can be losing
 265                                  * commits at the remote end and likely
 266                                  * we were not up to date to begin with.
 267                                  */
 268                                 error("remote '%s' is not a strict "
 269                                       "subset of local ref '%s'. "
 270                                       "maybe you are not up-to-date and "
 271                                       "need to pull first?",
 272                                       ref->name,
 273                                       ref->peer_ref->name);
 274                                 ret = -2;
 275                                 continue;
 276                         }
 277                 }
 278                 hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
 279                 if (!delete_ref)
 280                         new_refs++;
 281                 strcpy(old_hex, sha1_to_hex(ref->old_sha1));
 282                 new_hex = sha1_to_hex(ref->new_sha1);
 283
 284                 if (ask_for_status_report) {
 285                         packet_write(out, "%s %s %s%c%s",
 286                                      old_hex, new_hex, ref->name, 0,
 287                                      "report-status");
 288                         ask_for_status_report = 0;
 289                         expect_status_report = 1;
 290                 }
 291                 else
 292                         packet_write(out, "%s %s %s",
 293                                      old_hex, new_hex, ref->name);
 294                 if (delete_ref)
 295                         fprintf(stderr, "deleting '%s'\n", ref->name);
 296                 else {
 297                         fprintf(stderr, "updating '%s'", ref->name);
 298                         if (strcmp(ref->name, ref->peer_ref->name))
 299                                 fprintf(stderr, " using '%s'",
 300                                         ref->peer_ref->name);
 301                         fprintf(stderr, "\n  from %s\n  to   %s\n",
 302                                 old_hex, new_hex);
 303                 }
 304         }
 305
 306         packet_flush(out);
 307         if (new_refs)
 308                 ret = pack_objects(out, remote_refs);
 309         close(out);
 310
 311         if (expect_status_report) {
 312                 if (receive_status(in))
 313                         ret = -4;
 314         }
 315
 316         if (!new_refs && ret == 0)
 317                 fprintf(stderr, "Everything up-to-date\n");
 318         return ret;
 319 }
 320
 321 static void verify_remote_names(int nr_heads, char **heads)
 322 {
 323         int i;
 324
 325         for (i = 0; i < nr_heads; i++) {
 326                 const char *remote = strchr(heads[i], ':');
 327
 328                 remote = remote ? (remote + 1) : heads[i];
 329                 switch (check_ref_format(remote)) {
 330                 case 0: /* ok */
 331                 case -2: /* ok but a single level -- that is fine for
 332                           * a match pattern.
 333                           */
 334                         continue;
 335                 }
 336                 die("remote part of refspec is not a valid name in %s",
 337                     heads[i]);
 338         }
 339 }
 340
 341 int main(int argc, char **argv)
 342 {
 343         int i, nr_heads = 0;
 344         char *dest = NULL;
 345         char **heads = NULL;
 346         int fd[2], ret;
 347         pid_t pid;
 348
 349         setup_git_directory();
 350         git_config(git_default_config);
 351
 352         argv++;
 353         for (i = 1; i < argc; i++, argv++) {
 354                 char *arg = *argv;
 355
 356                 if (*arg == '-') {
 357                         if (!prefixcmp(arg, "--receive-pack=")) {
 358                                 receivepack = arg + 15;
 359                                 continue;
 360                         }
 361                         if (!prefixcmp(arg, "--exec=")) {
 362                                 receivepack = arg + 7;
 363                                 continue;
 364                         }
 365                         if (!strcmp(arg, "--all")) {
 366                                 send_all = 1;
 367                                 continue;
 368                         }
 369                         if (!strcmp(arg, "--force")) {
 370                                 force_update = 1;
 371                                 continue;
 372                         }
 373                         if (!strcmp(arg, "--verbose")) {
 374                                 verbose = 1;
 375                                 continue;
 376                         }
 377                         if (!strcmp(arg, "--thin")) {
 378                                 use_thin_pack = 1;
 379                                 continue;
 380                         }
 381                         usage(send_pack_usage);
 382                 }
 383                 if (!dest) {
 384                         dest = arg;
 385                         continue;
 386                 }
 387                 heads = argv;
 388                 nr_heads = argc - i;
 389                 break;
 390         }
 391         if (!dest)
 392                 usage(send_pack_usage);
 393         if (heads && send_all)
 394                 usage(send_pack_usage);
 395         verify_remote_names(nr_heads, heads);
 396
 397         pid = git_connect(fd, dest, receivepack, verbose ? CONNECT_VERBOSE : 0);
 398         if (pid < 0)
 399                 return 1;
 400         ret = send_pack(fd[0], fd[1], nr_heads, heads);
 401         close(fd[0]);
 402         close(fd[1]);
 403         ret |= finish_connect(pid);
 404         return !!ret;
 405 }