send-pack.con commit Elaborate on why ':' is a bad idea in a ref name. (87a56cd)
   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 = 0;
  13static int send_all = 0;
  14static int force_update = 0;
  15static int use_thin_pack = 0;
  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 int 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        return 0;
 130}
 131
 132static void unmark_and_free(struct commit_list *list, unsigned int mark)
 133{
 134        while (list) {
 135                struct commit_list *temp = list;
 136                temp->item->object.flags &= ~mark;
 137                list = temp->next;
 138                free(temp);
 139        }
 140}
 141
 142static int ref_newer(const unsigned char *new_sha1,
 143                     const unsigned char *old_sha1)
 144{
 145        struct object *o;
 146        struct commit *old, *new;
 147        struct commit_list *list, *used;
 148        int found = 0;
 149
 150        /* Both new and old must be commit-ish and new is descendant of
 151         * old.  Otherwise we require --force.
 152         */
 153        o = deref_tag(parse_object(old_sha1), NULL, 0);
 154        if (!o || o->type != commit_type)
 155                return 0;
 156        old = (struct commit *) o;
 157
 158        o = deref_tag(parse_object(new_sha1), NULL, 0);
 159        if (!o || o->type != commit_type)
 160                return 0;
 161        new = (struct commit *) o;
 162
 163        if (parse_commit(new) < 0)
 164                return 0;
 165
 166        used = list = NULL;
 167        commit_list_insert(new, &list);
 168        while (list) {
 169                new = pop_most_recent_commit(&list, 1);
 170                commit_list_insert(new, &used);
 171                if (new == old) {
 172                        found = 1;
 173                        break;
 174                }
 175        }
 176        unmark_and_free(list, 1);
 177        unmark_and_free(used, 1);
 178        return found;
 179}
 180
 181static struct ref *local_refs, **local_tail;
 182static struct ref *remote_refs, **remote_tail;
 183
 184static int one_local_ref(const char *refname, const unsigned char *sha1)
 185{
 186        struct ref *ref;
 187        int len = strlen(refname) + 1;
 188        ref = xcalloc(1, sizeof(*ref) + len);
 189        memcpy(ref->new_sha1, sha1, 20);
 190        memcpy(ref->name, refname, len);
 191        *local_tail = ref;
 192        local_tail = &ref->next;
 193        return 0;
 194}
 195
 196static void get_local_heads(void)
 197{
 198        local_tail = &local_refs;
 199        for_each_ref(one_local_ref);
 200}
 201
 202static int receive_status(int in)
 203{
 204        char line[1000];
 205        int ret = 0;
 206        int len = packet_read_line(in, line, sizeof(line));
 207        if (len < 10 || memcmp(line, "unpack ", 7)) {
 208                fprintf(stderr, "did not receive status back\n");
 209                return -1;
 210        }
 211        if (memcmp(line, "unpack ok\n", 10)) {
 212                fputs(line, stderr);
 213                ret = -1;
 214        }
 215        while (1) {
 216                len = packet_read_line(in, line, sizeof(line));
 217                if (!len)
 218                        break;
 219                if (len < 3 ||
 220                    (memcmp(line, "ok", 2) && memcmp(line, "ng", 2))) {
 221                        fprintf(stderr, "protocol error: %s\n", line);
 222                        ret = -1;
 223                        break;
 224                }
 225                if (!memcmp(line, "ok", 2))
 226                        continue;
 227                fputs(line, stderr);
 228                ret = -1;
 229        }
 230        return ret;
 231}
 232
 233static int send_pack(int in, int out, int nr_refspec, char **refspec)
 234{
 235        struct ref *ref;
 236        int new_refs;
 237        int ret = 0;
 238        int ask_for_status_report = 0;
 239        int expect_status_report = 0;
 240
 241        /* No funny business with the matcher */
 242        remote_tail = get_remote_heads(in, &remote_refs, 0, NULL, 1);
 243        get_local_heads();
 244
 245        /* Does the other end support the reporting? */
 246        if (server_supports("report-status"))
 247                ask_for_status_report = 1;
 248
 249        /* match them up */
 250        if (!remote_tail)
 251                remote_tail = &remote_refs;
 252        if (match_refs(local_refs, remote_refs, &remote_tail,
 253                       nr_refspec, refspec, send_all))
 254                return -1;
 255
 256        if (!remote_refs) {
 257                fprintf(stderr, "No refs in common and none specified; doing nothing.\n");
 258                return 0;
 259        }
 260
 261        /*
 262         * Finally, tell the other end!
 263         */
 264        new_refs = 0;
 265        for (ref = remote_refs; ref; ref = ref->next) {
 266                char old_hex[60], *new_hex;
 267                if (!ref->peer_ref)
 268                        continue;
 269                if (!memcmp(ref->old_sha1, ref->peer_ref->new_sha1, 20)) {
 270                        if (verbose)
 271                                fprintf(stderr, "'%s': up-to-date\n", ref->name);
 272                        continue;
 273                }
 274
 275                /* This part determines what can overwrite what.
 276                 * The rules are:
 277                 *
 278                 * (0) you can always use --force or +A:B notation to
 279                 *     selectively force individual ref pairs.
 280                 *
 281                 * (1) if the old thing does not exist, it is OK.
 282                 *
 283                 * (2) if you do not have the old thing, you are not allowed
 284                 *     to overwrite it; you would not know what you are losing
 285                 *     otherwise.
 286                 *
 287                 * (3) if both new and old are commit-ish, and new is a
 288                 *     descendant of old, it is OK.
 289                 */
 290
 291                if (!force_update &&
 292                    !is_zero_sha1(ref->old_sha1) &&
 293                    !ref->force) {
 294                        if (!has_sha1_file(ref->old_sha1) ||
 295                            !ref_newer(ref->peer_ref->new_sha1,
 296                                       ref->old_sha1)) {
 297                                /* We do not have the remote ref, or
 298                                 * we know that the remote ref is not
 299                                 * an ancestor of what we are trying to
 300                                 * push.  Either way this can be losing
 301                                 * commits at the remote end and likely
 302                                 * we were not up to date to begin with.
 303                                 */
 304                                error("remote '%s' is not a strict "
 305                                      "subset of local ref '%s'. "
 306                                      "maybe you are not up-to-date and "
 307                                      "need to pull first?",
 308                                      ref->name,
 309                                      ref->peer_ref->name);
 310                                ret = -2;
 311                                continue;
 312                        }
 313                }
 314                memcpy(ref->new_sha1, ref->peer_ref->new_sha1, 20);
 315                if (is_zero_sha1(ref->new_sha1)) {
 316                        error("cannot happen anymore");
 317                        ret = -3;
 318                        continue;
 319                }
 320                new_refs++;
 321                strcpy(old_hex, sha1_to_hex(ref->old_sha1));
 322                new_hex = sha1_to_hex(ref->new_sha1);
 323
 324                if (ask_for_status_report) {
 325                        packet_write(out, "%s %s %s%c%s",
 326                                     old_hex, new_hex, ref->name, 0,
 327                                     "report-status");
 328                        ask_for_status_report = 0;
 329                        expect_status_report = 1;
 330                }
 331                else
 332                        packet_write(out, "%s %s %s",
 333                                     old_hex, new_hex, ref->name);
 334                fprintf(stderr, "updating '%s'", ref->name);
 335                if (strcmp(ref->name, ref->peer_ref->name))
 336                        fprintf(stderr, " using '%s'", ref->peer_ref->name);
 337                fprintf(stderr, "\n  from %s\n  to   %s\n", old_hex, new_hex);
 338        }
 339
 340        packet_flush(out);
 341        if (new_refs)
 342                pack_objects(out, remote_refs);
 343        close(out);
 344
 345        if (expect_status_report) {
 346                if (receive_status(in))
 347                        ret = -4;
 348        }
 349
 350        if (!new_refs && ret == 0)
 351                fprintf(stderr, "Everything up-to-date\n");
 352        return ret;
 353}
 354
 355
 356int main(int argc, char **argv)
 357{
 358        int i, nr_heads = 0;
 359        char *dest = NULL;
 360        char **heads = NULL;
 361        int fd[2], ret;
 362        pid_t pid;
 363
 364        setup_git_directory();
 365        git_config(git_default_config);
 366
 367        argv++;
 368        for (i = 1; i < argc; i++, argv++) {
 369                char *arg = *argv;
 370
 371                if (*arg == '-') {
 372                        if (!strncmp(arg, "--exec=", 7)) {
 373                                exec = arg + 7;
 374                                continue;
 375                        }
 376                        if (!strcmp(arg, "--all")) {
 377                                send_all = 1;
 378                                continue;
 379                        }
 380                        if (!strcmp(arg, "--force")) {
 381                                force_update = 1;
 382                                continue;
 383                        }
 384                        if (!strcmp(arg, "--verbose")) {
 385                                verbose = 1;
 386                                continue;
 387                        }
 388                        if (!strcmp(arg, "--thin")) {
 389                                use_thin_pack = 1;
 390                                continue;
 391                        }
 392                        usage(send_pack_usage);
 393                }
 394                if (!dest) {
 395                        dest = arg;
 396                        continue;
 397                }
 398                heads = argv;
 399                nr_heads = argc - i;
 400                break;
 401        }
 402        if (!dest)
 403                usage(send_pack_usage);
 404        if (heads && send_all)
 405                usage(send_pack_usage);
 406        pid = git_connect(fd, dest, exec);
 407        if (pid < 0)
 408                return 1;
 409        ret = send_pack(fd[0], fd[1], nr_heads, heads);
 410        close(fd[0]);
 411        close(fd[1]);
 412        finish_connect(pid);
 413        return ret;
 414}