send-pack.con commit Merge branch 'jc/reflog' (c326246)
   1#include "cache.h"
   2#include "commit.h"
   3#include "tag.h"
   4#include "refs.h"
   5#include "pkt-line.h"
   6#include "exec_cmd.h"
   7
   8static const char send_pack_usage[] =
   9"git-send-pack [--all] [--exec=git-receive-pack] <remote> [<head>...]\n"
  10"  --all and explicit <head> specification are mutually exclusive.";
  11static const char *exec = "git-receive-pack";
  12static int verbose;
  13static int send_all;
  14static int force_update;
  15static int use_thin_pack;
  16
  17/*
  18 * Make a pack stream and spit it out into file descriptor fd
  19 */
  20static int pack_objects(int fd, struct ref *refs)
  21{
  22        int pipe_fd[2];
  23        pid_t pid;
  24
  25        if (pipe(pipe_fd) < 0)
  26                return error("send-pack: pipe failed");
  27        pid = fork();
  28        if (!pid) {
  29                /*
  30                 * The child becomes pack-objects --revs; we feed
  31                 * the revision parameters to it via its stdin and
  32                 * let its stdout go back to the other end.
  33                 */
  34                static const char *args[] = {
  35                        "pack-objects",
  36                        "--all-progress",
  37                        "--revs",
  38                        "--stdout",
  39                        NULL,
  40                        NULL,
  41                };
  42                if (use_thin_pack)
  43                        args[4] = "--thin";
  44                dup2(pipe_fd[0], 0);
  45                dup2(fd, 1);
  46                close(pipe_fd[0]);
  47                close(pipe_fd[1]);
  48                close(fd);
  49                execv_git_cmd(args);
  50                die("git-pack-objects exec failed (%s)", strerror(errno));
  51        }
  52
  53        /*
  54         * We feed the pack-objects we just spawned with revision
  55         * parameters by writing to the pipe.
  56         */
  57        close(pipe_fd[0]);
  58        close(fd);
  59
  60        while (refs) {
  61                char buf[42];
  62
  63                if (!is_null_sha1(refs->old_sha1) &&
  64                    has_sha1_file(refs->old_sha1)) {
  65                        memcpy(buf + 1, sha1_to_hex(refs->old_sha1), 40);
  66                        buf[0] = '^';
  67                        buf[41] = '\n';
  68                        if (!write_or_whine(pipe_fd[1], buf, 42,
  69                                                "send-pack: send refs"))
  70                                break;
  71                }
  72                if (!is_null_sha1(refs->new_sha1)) {
  73                        memcpy(buf, sha1_to_hex(refs->new_sha1), 40);
  74                        buf[40] = '\n';
  75                        if (!write_or_whine(pipe_fd[1], buf, 41,
  76                                                "send-pack: send refs"))
  77                                break;
  78                }
  79                refs = refs->next;
  80        }
  81        close(pipe_fd[1]);
  82
  83        for (;;) {
  84                int status, code;
  85                pid_t waiting = waitpid(pid, &status, 0);
  86
  87                if (waiting < 0) {
  88                        if (errno == EINTR)
  89                                continue;
  90                        return error("waitpid failed (%s)", strerror(errno));
  91                }
  92                if ((waiting != pid) || WIFSIGNALED(status) ||
  93                    !WIFEXITED(status))
  94                        return error("pack-objects died with strange error");
  95                code = WEXITSTATUS(status);
  96                if (code)
  97                        return -code;
  98                return 0;
  99        }
 100}
 101
 102static void unmark_and_free(struct commit_list *list, unsigned int mark)
 103{
 104        while (list) {
 105                struct commit_list *temp = list;
 106                temp->item->object.flags &= ~mark;
 107                list = temp->next;
 108                free(temp);
 109        }
 110}
 111
 112static int ref_newer(const unsigned char *new_sha1,
 113                     const unsigned char *old_sha1)
 114{
 115        struct object *o;
 116        struct commit *old, *new;
 117        struct commit_list *list, *used;
 118        int found = 0;
 119
 120        /* Both new and old must be commit-ish and new is descendant of
 121         * old.  Otherwise we require --force.
 122         */
 123        o = deref_tag(parse_object(old_sha1), NULL, 0);
 124        if (!o || o->type != OBJ_COMMIT)
 125                return 0;
 126        old = (struct commit *) o;
 127
 128        o = deref_tag(parse_object(new_sha1), NULL, 0);
 129        if (!o || o->type != OBJ_COMMIT)
 130                return 0;
 131        new = (struct commit *) o;
 132
 133        if (parse_commit(new) < 0)
 134                return 0;
 135
 136        used = list = NULL;
 137        commit_list_insert(new, &list);
 138        while (list) {
 139                new = pop_most_recent_commit(&list, 1);
 140                commit_list_insert(new, &used);
 141                if (new == old) {
 142                        found = 1;
 143                        break;
 144                }
 145        }
 146        unmark_and_free(list, 1);
 147        unmark_and_free(used, 1);
 148        return found;
 149}
 150
 151static struct ref *local_refs, **local_tail;
 152static struct ref *remote_refs, **remote_tail;
 153
 154static int one_local_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 155{
 156        struct ref *ref;
 157        int len = strlen(refname) + 1;
 158        ref = xcalloc(1, sizeof(*ref) + len);
 159        hashcpy(ref->new_sha1, sha1);
 160        memcpy(ref->name, refname, len);
 161        *local_tail = ref;
 162        local_tail = &ref->next;
 163        return 0;
 164}
 165
 166static void get_local_heads(void)
 167{
 168        local_tail = &local_refs;
 169        for_each_ref(one_local_ref, NULL);
 170}
 171
 172static int receive_status(int in)
 173{
 174        char line[1000];
 175        int ret = 0;
 176        int len = packet_read_line(in, line, sizeof(line));
 177        if (len < 10 || memcmp(line, "unpack ", 7)) {
 178                fprintf(stderr, "did not receive status back\n");
 179                return -1;
 180        }
 181        if (memcmp(line, "unpack ok\n", 10)) {
 182                fputs(line, stderr);
 183                ret = -1;
 184        }
 185        while (1) {
 186                len = packet_read_line(in, line, sizeof(line));
 187                if (!len)
 188                        break;
 189                if (len < 3 ||
 190                    (memcmp(line, "ok", 2) && memcmp(line, "ng", 2))) {
 191                        fprintf(stderr, "protocol error: %s\n", line);
 192                        ret = -1;
 193                        break;
 194                }
 195                if (!memcmp(line, "ok", 2))
 196                        continue;
 197                fputs(line, stderr);
 198                ret = -1;
 199        }
 200        return ret;
 201}
 202
 203static int send_pack(int in, int out, int nr_refspec, char **refspec)
 204{
 205        struct ref *ref;
 206        int new_refs;
 207        int ret = 0;
 208        int ask_for_status_report = 0;
 209        int allow_deleting_refs = 0;
 210        int expect_status_report = 0;
 211
 212        /* No funny business with the matcher */
 213        remote_tail = get_remote_heads(in, &remote_refs, 0, NULL, REF_NORMAL);
 214        get_local_heads();
 215
 216        /* Does the other end support the reporting? */
 217        if (server_supports("report-status"))
 218                ask_for_status_report = 1;
 219        if (server_supports("delete-refs"))
 220                allow_deleting_refs = 1;
 221
 222        /* match them up */
 223        if (!remote_tail)
 224                remote_tail = &remote_refs;
 225        if (match_refs(local_refs, remote_refs, &remote_tail,
 226                       nr_refspec, refspec, send_all))
 227                return -1;
 228
 229        if (!remote_refs) {
 230                fprintf(stderr, "No refs in common and none specified; doing nothing.\n");
 231                return 0;
 232        }
 233
 234        /*
 235         * Finally, tell the other end!
 236         */
 237        new_refs = 0;
 238        for (ref = remote_refs; ref; ref = ref->next) {
 239                char old_hex[60], *new_hex;
 240                int delete_ref;
 241
 242                if (!ref->peer_ref)
 243                        continue;
 244
 245                delete_ref = is_null_sha1(ref->peer_ref->new_sha1);
 246                if (delete_ref && !allow_deleting_refs) {
 247                        error("remote does not support deleting refs");
 248                        ret = -2;
 249                        continue;
 250                }
 251                if (!delete_ref &&
 252                    !hashcmp(ref->old_sha1, ref->peer_ref->new_sha1)) {
 253                        if (verbose)
 254                                fprintf(stderr, "'%s': up-to-date\n", ref->name);
 255                        continue;
 256                }
 257
 258                /* This part determines what can overwrite what.
 259                 * The rules are:
 260                 *
 261                 * (0) you can always use --force or +A:B notation to
 262                 *     selectively force individual ref pairs.
 263                 *
 264                 * (1) if the old thing does not exist, it is OK.
 265                 *
 266                 * (2) if you do not have the old thing, you are not allowed
 267                 *     to overwrite it; you would not know what you are losing
 268                 *     otherwise.
 269                 *
 270                 * (3) if both new and old are commit-ish, and new is a
 271                 *     descendant of old, it is OK.
 272                 *
 273                 * (4) regardless of all of the above, removing :B is
 274                 *     always allowed.
 275                 */
 276
 277                if (!force_update &&
 278                    !delete_ref &&
 279                    !is_null_sha1(ref->old_sha1) &&
 280                    !ref->force) {
 281                        if (!has_sha1_file(ref->old_sha1) ||
 282                            !ref_newer(ref->peer_ref->new_sha1,
 283                                       ref->old_sha1)) {
 284                                /* We do not have the remote ref, or
 285                                 * we know that the remote ref is not
 286                                 * an ancestor of what we are trying to
 287                                 * push.  Either way this can be losing
 288                                 * commits at the remote end and likely
 289                                 * we were not up to date to begin with.
 290                                 */
 291                                error("remote '%s' is not a strict "
 292                                      "subset of local ref '%s'. "
 293                                      "maybe you are not up-to-date and "
 294                                      "need to pull first?",
 295                                      ref->name,
 296                                      ref->peer_ref->name);
 297                                ret = -2;
 298                                continue;
 299                        }
 300                }
 301                hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
 302                if (!delete_ref)
 303                        new_refs++;
 304                strcpy(old_hex, sha1_to_hex(ref->old_sha1));
 305                new_hex = sha1_to_hex(ref->new_sha1);
 306
 307                if (ask_for_status_report) {
 308                        packet_write(out, "%s %s %s%c%s",
 309                                     old_hex, new_hex, ref->name, 0,
 310                                     "report-status");
 311                        ask_for_status_report = 0;
 312                        expect_status_report = 1;
 313                }
 314                else
 315                        packet_write(out, "%s %s %s",
 316                                     old_hex, new_hex, ref->name);
 317                if (delete_ref)
 318                        fprintf(stderr, "deleting '%s'\n", ref->name);
 319                else {
 320                        fprintf(stderr, "updating '%s'", ref->name);
 321                        if (strcmp(ref->name, ref->peer_ref->name))
 322                                fprintf(stderr, " using '%s'",
 323                                        ref->peer_ref->name);
 324                        fprintf(stderr, "\n  from %s\n  to   %s\n",
 325                                old_hex, new_hex);
 326                }
 327        }
 328
 329        packet_flush(out);
 330        if (new_refs)
 331                ret = pack_objects(out, remote_refs);
 332        close(out);
 333
 334        if (expect_status_report) {
 335                if (receive_status(in))
 336                        ret = -4;
 337        }
 338
 339        if (!new_refs && ret == 0)
 340                fprintf(stderr, "Everything up-to-date\n");
 341        return ret;
 342}
 343
 344static void verify_remote_names(int nr_heads, char **heads)
 345{
 346        int i;
 347
 348        for (i = 0; i < nr_heads; i++) {
 349                const char *remote = strchr(heads[i], ':');
 350
 351                remote = remote ? (remote + 1) : heads[i];
 352                switch (check_ref_format(remote)) {
 353                case 0: /* ok */
 354                case -2: /* ok but a single level -- that is fine for
 355                          * a match pattern.
 356                          */
 357                        continue;
 358                }
 359                die("remote part of refspec is not a valid name in %s",
 360                    heads[i]);
 361        }
 362}
 363
 364int main(int argc, char **argv)
 365{
 366        int i, nr_heads = 0;
 367        char *dest = NULL;
 368        char **heads = NULL;
 369        int fd[2], ret;
 370        pid_t pid;
 371
 372        setup_git_directory();
 373        git_config(git_default_config);
 374
 375        argv++;
 376        for (i = 1; i < argc; i++, argv++) {
 377                char *arg = *argv;
 378
 379                if (*arg == '-') {
 380                        if (!strncmp(arg, "--exec=", 7)) {
 381                                exec = arg + 7;
 382                                continue;
 383                        }
 384                        if (!strcmp(arg, "--all")) {
 385                                send_all = 1;
 386                                continue;
 387                        }
 388                        if (!strcmp(arg, "--force")) {
 389                                force_update = 1;
 390                                continue;
 391                        }
 392                        if (!strcmp(arg, "--verbose")) {
 393                                verbose = 1;
 394                                continue;
 395                        }
 396                        if (!strcmp(arg, "--thin")) {
 397                                use_thin_pack = 1;
 398                                continue;
 399                        }
 400                        usage(send_pack_usage);
 401                }
 402                if (!dest) {
 403                        dest = arg;
 404                        continue;
 405                }
 406                heads = argv;
 407                nr_heads = argc - i;
 408                break;
 409        }
 410        if (!dest)
 411                usage(send_pack_usage);
 412        if (heads && send_all)
 413                usage(send_pack_usage);
 414        verify_remote_names(nr_heads, heads);
 415
 416        pid = git_connect(fd, dest, exec);
 417        if (pid < 0)
 418                return 1;
 419        ret = send_pack(fd[0], fd[1], nr_heads, heads);
 420        close(fd[0]);
 421        close(fd[1]);
 422        ret |= finish_connect(pid);
 423        return !!ret;
 424}