send-pack.con commit Cleanup unpack_object_header to use only offsets. (465b26e)
   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
  17static int is_zero_sha1(const unsigned char *sha1)
  18{
  19        int i;
  20
  21        for (i = 0; i < 20; i++) {
  22                if (*sha1++)
  23                        return 0;
  24        }
  25        return 1;
  26}
  27
  28static void exec_pack_objects(void)
  29{
  30        static const char *args[] = {
  31                "pack-objects",
  32                "--stdout",
  33                NULL
  34        };
  35        execv_git_cmd(args);
  36        die("git-pack-objects exec failed (%s)", strerror(errno));
  37}
  38
  39static void exec_rev_list(struct ref *refs)
  40{
  41        struct ref *ref;
  42        static const char *args[1000];
  43        int i = 0, j;
  44
  45        args[i++] = "rev-list"; /* 0 */
  46        if (use_thin_pack)      /* 1 */
  47                args[i++] = "--objects-edge";
  48        else
  49                args[i++] = "--objects";
  50
  51        /* First send the ones we care about most */
  52        for (ref = refs; ref; ref = ref->next) {
  53                if (900 < i)
  54                        die("git-rev-list environment overflow");
  55                if (!is_zero_sha1(ref->new_sha1)) {
  56                        char *buf = malloc(100);
  57                        args[i++] = buf;
  58                        snprintf(buf, 50, "%s", sha1_to_hex(ref->new_sha1));
  59                        buf += 50;
  60                        if (!is_zero_sha1(ref->old_sha1) &&
  61                            has_sha1_file(ref->old_sha1)) {
  62                                args[i++] = buf;
  63                                snprintf(buf, 50, "^%s",
  64                                         sha1_to_hex(ref->old_sha1));
  65                        }
  66                }
  67        }
  68
  69        /* Then a handful of the remainder
  70         * NEEDSWORK: we would be better off if used the newer ones first.
  71         */
  72        for (ref = refs, j = i + 16;
  73             i < 900 && i < j && ref;
  74             ref = ref->next) {
  75                if (is_zero_sha1(ref->new_sha1) &&
  76                    !is_zero_sha1(ref->old_sha1) &&
  77                    has_sha1_file(ref->old_sha1)) {
  78                        char *buf = malloc(42);
  79                        args[i++] = buf;
  80                        snprintf(buf, 42, "^%s", sha1_to_hex(ref->old_sha1));
  81                }
  82        }
  83        args[i] = NULL;
  84        execv_git_cmd(args);
  85        die("git-rev-list exec failed (%s)", strerror(errno));
  86}
  87
  88static void rev_list(int fd, struct ref *refs)
  89{
  90        int pipe_fd[2];
  91        pid_t pack_objects_pid;
  92
  93        if (pipe(pipe_fd) < 0)
  94                die("rev-list setup: pipe failed");
  95        pack_objects_pid = fork();
  96        if (!pack_objects_pid) {
  97                dup2(pipe_fd[0], 0);
  98                dup2(fd, 1);
  99                close(pipe_fd[0]);
 100                close(pipe_fd[1]);
 101                close(fd);
 102                exec_pack_objects();
 103                die("pack-objects setup failed");
 104        }
 105        if (pack_objects_pid < 0)
 106                die("pack-objects fork failed");
 107        dup2(pipe_fd[1], 1);
 108        close(pipe_fd[0]);
 109        close(pipe_fd[1]);
 110        close(fd);
 111        exec_rev_list(refs);
 112}
 113
 114static void pack_objects(int fd, struct ref *refs)
 115{
 116        pid_t rev_list_pid;
 117
 118        rev_list_pid = fork();
 119        if (!rev_list_pid) {
 120                rev_list(fd, refs);
 121                die("rev-list setup failed");
 122        }
 123        if (rev_list_pid < 0)
 124                die("rev-list fork failed");
 125        /*
 126         * We don't wait for the rev-list pipeline in the parent:
 127         * we end up waiting for the other end instead
 128         */
 129}
 130
 131static void unmark_and_free(struct commit_list *list, unsigned int mark)
 132{
 133        while (list) {
 134                struct commit_list *temp = list;
 135                temp->item->object.flags &= ~mark;
 136                list = temp->next;
 137                free(temp);
 138        }
 139}
 140
 141static int ref_newer(const unsigned char *new_sha1,
 142                     const unsigned char *old_sha1)
 143{
 144        struct object *o;
 145        struct commit *old, *new;
 146        struct commit_list *list, *used;
 147        int found = 0;
 148
 149        /* Both new and old must be commit-ish and new is descendant of
 150         * old.  Otherwise we require --force.
 151         */
 152        o = deref_tag(parse_object(old_sha1), NULL, 0);
 153        if (!o || o->type != OBJ_COMMIT)
 154                return 0;
 155        old = (struct commit *) o;
 156
 157        o = deref_tag(parse_object(new_sha1), NULL, 0);
 158        if (!o || o->type != OBJ_COMMIT)
 159                return 0;
 160        new = (struct commit *) o;
 161
 162        if (parse_commit(new) < 0)
 163                return 0;
 164
 165        used = list = NULL;
 166        commit_list_insert(new, &list);
 167        while (list) {
 168                new = pop_most_recent_commit(&list, 1);
 169                commit_list_insert(new, &used);
 170                if (new == old) {
 171                        found = 1;
 172                        break;
 173                }
 174        }
 175        unmark_and_free(list, 1);
 176        unmark_and_free(used, 1);
 177        return found;
 178}
 179
 180static struct ref *local_refs, **local_tail;
 181static struct ref *remote_refs, **remote_tail;
 182
 183static int one_local_ref(const char *refname, const unsigned char *sha1)
 184{
 185        struct ref *ref;
 186        int len = strlen(refname) + 1;
 187        ref = xcalloc(1, sizeof(*ref) + len);
 188        hashcpy(ref->new_sha1, sha1);
 189        memcpy(ref->name, refname, len);
 190        *local_tail = ref;
 191        local_tail = &ref->next;
 192        return 0;
 193}
 194
 195static void get_local_heads(void)
 196{
 197        local_tail = &local_refs;
 198        for_each_ref(one_local_ref);
 199}
 200
 201static int receive_status(int in)
 202{
 203        char line[1000];
 204        int ret = 0;
 205        int len = packet_read_line(in, line, sizeof(line));
 206        if (len < 10 || memcmp(line, "unpack ", 7)) {
 207                fprintf(stderr, "did not receive status back\n");
 208                return -1;
 209        }
 210        if (memcmp(line, "unpack ok\n", 10)) {
 211                fputs(line, stderr);
 212                ret = -1;
 213        }
 214        while (1) {
 215                len = packet_read_line(in, line, sizeof(line));
 216                if (!len)
 217                        break;
 218                if (len < 3 ||
 219                    (memcmp(line, "ok", 2) && memcmp(line, "ng", 2))) {
 220                        fprintf(stderr, "protocol error: %s\n", line);
 221                        ret = -1;
 222                        break;
 223                }
 224                if (!memcmp(line, "ok", 2))
 225                        continue;
 226                fputs(line, stderr);
 227                ret = -1;
 228        }
 229        return ret;
 230}
 231
 232static int send_pack(int in, int out, int nr_refspec, char **refspec)
 233{
 234        struct ref *ref;
 235        int new_refs;
 236        int ret = 0;
 237        int ask_for_status_report = 0;
 238        int expect_status_report = 0;
 239
 240        /* No funny business with the matcher */
 241        remote_tail = get_remote_heads(in, &remote_refs, 0, NULL, REF_NORMAL);
 242        get_local_heads();
 243
 244        /* Does the other end support the reporting? */
 245        if (server_supports("report-status"))
 246                ask_for_status_report = 1;
 247
 248        /* match them up */
 249        if (!remote_tail)
 250                remote_tail = &remote_refs;
 251        if (match_refs(local_refs, remote_refs, &remote_tail,
 252                       nr_refspec, refspec, send_all))
 253                return -1;
 254
 255        if (!remote_refs) {
 256                fprintf(stderr, "No refs in common and none specified; doing nothing.\n");
 257                return 0;
 258        }
 259
 260        /*
 261         * Finally, tell the other end!
 262         */
 263        new_refs = 0;
 264        for (ref = remote_refs; ref; ref = ref->next) {
 265                char old_hex[60], *new_hex;
 266                if (!ref->peer_ref)
 267                        continue;
 268                if (!hashcmp(ref->old_sha1, ref->peer_ref->new_sha1)) {
 269                        if (verbose)
 270                                fprintf(stderr, "'%s': up-to-date\n", ref->name);
 271                        continue;
 272                }
 273
 274                /* This part determines what can overwrite what.
 275                 * The rules are:
 276                 *
 277                 * (0) you can always use --force or +A:B notation to
 278                 *     selectively force individual ref pairs.
 279                 *
 280                 * (1) if the old thing does not exist, it is OK.
 281                 *
 282                 * (2) if you do not have the old thing, you are not allowed
 283                 *     to overwrite it; you would not know what you are losing
 284                 *     otherwise.
 285                 *
 286                 * (3) if both new and old are commit-ish, and new is a
 287                 *     descendant of old, it is OK.
 288                 */
 289
 290                if (!force_update &&
 291                    !is_zero_sha1(ref->old_sha1) &&
 292                    !ref->force) {
 293                        if (!has_sha1_file(ref->old_sha1) ||
 294                            !ref_newer(ref->peer_ref->new_sha1,
 295                                       ref->old_sha1)) {
 296                                /* We do not have the remote ref, or
 297                                 * we know that the remote ref is not
 298                                 * an ancestor of what we are trying to
 299                                 * push.  Either way this can be losing
 300                                 * commits at the remote end and likely
 301                                 * we were not up to date to begin with.
 302                                 */
 303                                error("remote '%s' is not a strict "
 304                                      "subset of local ref '%s'. "
 305                                      "maybe you are not up-to-date and "
 306                                      "need to pull first?",
 307                                      ref->name,
 308                                      ref->peer_ref->name);
 309                                ret = -2;
 310                                continue;
 311                        }
 312                }
 313                hashcpy(ref->new_sha1, ref->peer_ref->new_sha1);
 314                if (is_zero_sha1(ref->new_sha1)) {
 315                        error("cannot happen anymore");
 316                        ret = -3;
 317                        continue;
 318                }
 319                new_refs++;
 320                strcpy(old_hex, sha1_to_hex(ref->old_sha1));
 321                new_hex = sha1_to_hex(ref->new_sha1);
 322
 323                if (ask_for_status_report) {
 324                        packet_write(out, "%s %s %s%c%s",
 325                                     old_hex, new_hex, ref->name, 0,
 326                                     "report-status");
 327                        ask_for_status_report = 0;
 328                        expect_status_report = 1;
 329                }
 330                else
 331                        packet_write(out, "%s %s %s",
 332                                     old_hex, new_hex, ref->name);
 333                fprintf(stderr, "updating '%s'", ref->name);
 334                if (strcmp(ref->name, ref->peer_ref->name))
 335                        fprintf(stderr, " using '%s'", ref->peer_ref->name);
 336                fprintf(stderr, "\n  from %s\n  to   %s\n", old_hex, new_hex);
 337        }
 338
 339        packet_flush(out);
 340        if (new_refs)
 341                pack_objects(out, remote_refs);
 342        close(out);
 343
 344        if (expect_status_report) {
 345                if (receive_status(in))
 346                        ret = -4;
 347        }
 348
 349        if (!new_refs && ret == 0)
 350                fprintf(stderr, "Everything up-to-date\n");
 351        return ret;
 352}
 353
 354
 355int main(int argc, char **argv)
 356{
 357        int i, nr_heads = 0;
 358        char *dest = NULL;
 359        char **heads = NULL;
 360        int fd[2], ret;
 361        pid_t pid;
 362
 363        setup_git_directory();
 364        git_config(git_default_config);
 365
 366        argv++;
 367        for (i = 1; i < argc; i++, argv++) {
 368                char *arg = *argv;
 369
 370                if (*arg == '-') {
 371                        if (!strncmp(arg, "--exec=", 7)) {
 372                                exec = arg + 7;
 373                                continue;
 374                        }
 375                        if (!strcmp(arg, "--all")) {
 376                                send_all = 1;
 377                                continue;
 378                        }
 379                        if (!strcmp(arg, "--force")) {
 380                                force_update = 1;
 381                                continue;
 382                        }
 383                        if (!strcmp(arg, "--verbose")) {
 384                                verbose = 1;
 385                                continue;
 386                        }
 387                        if (!strcmp(arg, "--thin")) {
 388                                use_thin_pack = 1;
 389                                continue;
 390                        }
 391                        usage(send_pack_usage);
 392                }
 393                if (!dest) {
 394                        dest = arg;
 395                        continue;
 396                }
 397                heads = argv;
 398                nr_heads = argc - i;
 399                break;
 400        }
 401        if (!dest)
 402                usage(send_pack_usage);
 403        if (heads && send_all)
 404                usage(send_pack_usage);
 405        pid = git_connect(fd, dest, exec);
 406        if (pid < 0)
 407                return 1;
 408        ret = send_pack(fd[0], fd[1], nr_heads, heads);
 409        close(fd[0]);
 410        close(fd[1]);
 411        finish_connect(pid);
 412        return ret;
 413}