send-pack.con commit send-pack/receive-pack: allow errors to be reported back to pusher. (cfee10a)
   1#include "cache.h"
   2#include "commit.h"
   3#include "tag.h"
   4#include "refs.h"
   5#include "pkt-line.h"
   6
   7static const char send_pack_usage[] =
   8"git-send-pack [--all] [--exec=git-receive-pack] <remote> [<head>...]\n"
   9"  --all and explicit <head> specification are mutually exclusive.";
  10static const char *exec = "git-receive-pack";
  11static int verbose = 0;
  12static int send_all = 0;
  13static int force_update = 0;
  14
  15static int is_zero_sha1(const unsigned char *sha1)
  16{
  17        int i;
  18
  19        for (i = 0; i < 20; i++) {
  20                if (*sha1++)
  21                        return 0;
  22        }
  23        return 1;
  24}
  25
  26static void exec_pack_objects(void)
  27{
  28        static char *args[] = {
  29                "git-pack-objects",
  30                "--stdout",
  31                NULL
  32        };
  33        execvp("git-pack-objects", args);
  34        die("git-pack-objects exec failed (%s)", strerror(errno));
  35}
  36
  37static void exec_rev_list(struct ref *refs)
  38{
  39        static char *args[1000];
  40        int i = 0;
  41
  42        args[i++] = "git-rev-list";     /* 0 */
  43        args[i++] = "--objects";        /* 1 */
  44        while (refs) {
  45                char *buf = malloc(100);
  46                if (i > 900)
  47                        die("git-rev-list environment overflow");
  48                if (!is_zero_sha1(refs->old_sha1) &&
  49                    has_sha1_file(refs->old_sha1)) {
  50                        args[i++] = buf;
  51                        snprintf(buf, 50, "^%s", sha1_to_hex(refs->old_sha1));
  52                        buf += 50;
  53                }
  54                if (!is_zero_sha1(refs->new_sha1)) {
  55                        args[i++] = buf;
  56                        snprintf(buf, 50, "%s", sha1_to_hex(refs->new_sha1));
  57                }
  58                refs = refs->next;
  59        }
  60        args[i] = NULL;
  61        execvp("git-rev-list", args);
  62        die("git-rev-list exec failed (%s)", strerror(errno));
  63}
  64
  65static void rev_list(int fd, struct ref *refs)
  66{
  67        int pipe_fd[2];
  68        pid_t pack_objects_pid;
  69
  70        if (pipe(pipe_fd) < 0)
  71                die("rev-list setup: pipe failed");
  72        pack_objects_pid = fork();
  73        if (!pack_objects_pid) {
  74                dup2(pipe_fd[0], 0);
  75                dup2(fd, 1);
  76                close(pipe_fd[0]);
  77                close(pipe_fd[1]);
  78                close(fd);
  79                exec_pack_objects();
  80                die("pack-objects setup failed");
  81        }
  82        if (pack_objects_pid < 0)
  83                die("pack-objects fork failed");
  84        dup2(pipe_fd[1], 1);
  85        close(pipe_fd[0]);
  86        close(pipe_fd[1]);
  87        close(fd);
  88        exec_rev_list(refs);
  89}
  90
  91static int pack_objects(int fd, struct ref *refs)
  92{
  93        pid_t rev_list_pid;
  94
  95        rev_list_pid = fork();
  96        if (!rev_list_pid) {
  97                rev_list(fd, refs);
  98                die("rev-list setup failed");
  99        }
 100        if (rev_list_pid < 0)
 101                die("rev-list fork failed");
 102        /*
 103         * We don't wait for the rev-list pipeline in the parent:
 104         * we end up waiting for the other end instead
 105         */
 106        return 0;
 107}
 108
 109static void unmark_and_free(struct commit_list *list, unsigned int mark)
 110{
 111        while (list) {
 112                struct commit_list *temp = list;
 113                temp->item->object.flags &= ~mark;
 114                list = temp->next;
 115                free(temp);
 116        }
 117}
 118
 119static int ref_newer(const unsigned char *new_sha1,
 120                     const unsigned char *old_sha1)
 121{
 122        struct object *o;
 123        struct commit *old, *new;
 124        struct commit_list *list, *used;
 125        int found = 0;
 126
 127        /* Both new and old must be commit-ish and new is descendant of
 128         * old.  Otherwise we require --force.
 129         */
 130        o = deref_tag(parse_object(old_sha1), NULL, 0);
 131        if (!o || o->type != commit_type)
 132                return 0;
 133        old = (struct commit *) o;
 134
 135        o = deref_tag(parse_object(new_sha1), NULL, 0);
 136        if (!o || o->type != commit_type)
 137                return 0;
 138        new = (struct commit *) o;
 139
 140        if (parse_commit(new) < 0)
 141                return 0;
 142
 143        used = list = NULL;
 144        commit_list_insert(new, &list);
 145        while (list) {
 146                new = pop_most_recent_commit(&list, 1);
 147                commit_list_insert(new, &used);
 148                if (new == old) {
 149                        found = 1;
 150                        break;
 151                }
 152        }
 153        unmark_and_free(list, 1);
 154        unmark_and_free(used, 1);
 155        return found;
 156}
 157
 158static struct ref *local_refs, **local_tail;
 159static struct ref *remote_refs, **remote_tail;
 160
 161static int one_local_ref(const char *refname, const unsigned char *sha1)
 162{
 163        struct ref *ref;
 164        int len = strlen(refname) + 1;
 165        ref = xcalloc(1, sizeof(*ref) + len);
 166        memcpy(ref->new_sha1, sha1, 20);
 167        memcpy(ref->name, refname, len);
 168        *local_tail = ref;
 169        local_tail = &ref->next;
 170        return 0;
 171}
 172
 173static void get_local_heads(void)
 174{
 175        local_tail = &local_refs;
 176        for_each_ref(one_local_ref);
 177}
 178
 179static int receive_status(int in)
 180{
 181        char line[1000];
 182        int ret = 0;
 183        int len = packet_read_line(in, line, sizeof(line));
 184        if (len < 10 || memcmp(line, "unpack ", 7)) {
 185                fprintf(stderr, "did not receive status back\n");
 186                return -1;
 187        }
 188        if (memcmp(line, "unpack ok\n", 10)) {
 189                fputs(line, stderr);
 190                ret = -1;
 191        }
 192        while (1) {
 193                len = packet_read_line(in, line, sizeof(line));
 194                if (!len)
 195                        break;
 196                if (len < 3 ||
 197                    (memcmp(line, "ok", 2) && memcmp(line, "ng", 2))) {
 198                        fprintf(stderr, "protocol error: %s\n", line);
 199                        ret = -1;
 200                        break;
 201                }
 202                if (!memcmp(line, "ok", 2))
 203                        continue;
 204                fputs(line, stderr);
 205                ret = -1;
 206        }
 207        return ret;
 208}
 209
 210static int send_pack(int in, int out, int nr_refspec, char **refspec)
 211{
 212        struct ref *ref;
 213        int new_refs;
 214        int ret = 0;
 215        int ask_for_status_report = 0;
 216        int expect_status_report = 0;
 217
 218        /* No funny business with the matcher */
 219        remote_tail = get_remote_heads(in, &remote_refs, 0, NULL, 1);
 220        get_local_heads();
 221
 222        /* Does the other end support the reporting? */
 223        if (server_supports("report-status"))
 224                ask_for_status_report = 1;
 225
 226        /* match them up */
 227        if (!remote_tail)
 228                remote_tail = &remote_refs;
 229        if (match_refs(local_refs, remote_refs, &remote_tail,
 230                       nr_refspec, refspec, send_all))
 231                return -1;
 232
 233        if (!remote_refs) {
 234                fprintf(stderr, "No refs in common and none specified; doing nothing.\n");
 235                return 0;
 236        }
 237
 238        /*
 239         * Finally, tell the other end!
 240         */
 241        new_refs = 0;
 242        for (ref = remote_refs; ref; ref = ref->next) {
 243                char old_hex[60], *new_hex;
 244                if (!ref->peer_ref)
 245                        continue;
 246                if (!memcmp(ref->old_sha1, ref->peer_ref->new_sha1, 20)) {
 247                        if (verbose)
 248                                fprintf(stderr, "'%s': up-to-date\n", ref->name);
 249                        continue;
 250                }
 251
 252                /* This part determines what can overwrite what.
 253                 * The rules are:
 254                 *
 255                 * (0) you can always use --force or +A:B notation to
 256                 *     selectively force individual ref pairs.
 257                 *
 258                 * (1) if the old thing does not exist, it is OK.
 259                 *
 260                 * (2) if you do not have the old thing, you are not allowed
 261                 *     to overwrite it; you would not know what you are losing
 262                 *     otherwise.
 263                 *
 264                 * (3) if both new and old are commit-ish, and new is a
 265                 *     descendant of old, it is OK.
 266                 */
 267
 268                if (!force_update &&
 269                    !is_zero_sha1(ref->old_sha1) &&
 270                    !ref->force) {
 271                        if (!has_sha1_file(ref->old_sha1) ||
 272                            !ref_newer(ref->peer_ref->new_sha1,
 273                                       ref->old_sha1)) {
 274                                /* We do not have the remote ref, or
 275                                 * we know that the remote ref is not
 276                                 * an ancestor of what we are trying to
 277                                 * push.  Either way this can be losing
 278                                 * commits at the remote end and likely
 279                                 * we were not up to date to begin with.
 280                                 */
 281                                error("remote '%s' is not a strict "
 282                                      "subset of local ref '%s'. "
 283                                      "maybe you are not up-to-date and "
 284                                      "need to pull first?",
 285                                      ref->name,
 286                                      ref->peer_ref->name);
 287                                ret = -2;
 288                                continue;
 289                        }
 290                }
 291                memcpy(ref->new_sha1, ref->peer_ref->new_sha1, 20);
 292                if (is_zero_sha1(ref->new_sha1)) {
 293                        error("cannot happen anymore");
 294                        ret = -3;
 295                        continue;
 296                }
 297                new_refs++;
 298                strcpy(old_hex, sha1_to_hex(ref->old_sha1));
 299                new_hex = sha1_to_hex(ref->new_sha1);
 300
 301                if (ask_for_status_report) {
 302                        packet_write(out, "%s %s %s%c%s",
 303                                     old_hex, new_hex, ref->name, 0,
 304                                     "report-status");
 305                        ask_for_status_report = 0;
 306                        expect_status_report = 1;
 307                }
 308                else
 309                        packet_write(out, "%s %s %s",
 310                                     old_hex, new_hex, ref->name);
 311                fprintf(stderr, "updating '%s'", ref->name);
 312                if (strcmp(ref->name, ref->peer_ref->name))
 313                        fprintf(stderr, " using '%s'", ref->peer_ref->name);
 314                fprintf(stderr, "\n  from %s\n  to   %s\n", old_hex, new_hex);
 315        }
 316
 317        packet_flush(out);
 318        if (new_refs)
 319                pack_objects(out, remote_refs);
 320        close(out);
 321
 322        if (expect_status_report) {
 323                if (receive_status(in))
 324                        ret = -4;
 325        }
 326
 327        if (!new_refs && ret == 0)
 328                fprintf(stderr, "Everything up-to-date\n");
 329        return ret;
 330}
 331
 332
 333int main(int argc, char **argv)
 334{
 335        int i, nr_heads = 0;
 336        char *dest = NULL;
 337        char **heads = NULL;
 338        int fd[2], ret;
 339        pid_t pid;
 340
 341        setup_git_directory();
 342        argv++;
 343        for (i = 1; i < argc; i++, argv++) {
 344                char *arg = *argv;
 345
 346                if (*arg == '-') {
 347                        if (!strncmp(arg, "--exec=", 7)) {
 348                                exec = arg + 7;
 349                                continue;
 350                        }
 351                        if (!strcmp(arg, "--all")) {
 352                                send_all = 1;
 353                                continue;
 354                        }
 355                        if (!strcmp(arg, "--force")) {
 356                                force_update = 1;
 357                                continue;
 358                        }
 359                        if (!strcmp(arg, "--verbose")) {
 360                                verbose = 1;
 361                                continue;
 362                        }
 363                        usage(send_pack_usage);
 364                }
 365                if (!dest) {
 366                        dest = arg;
 367                        continue;
 368                }
 369                heads = argv;
 370                nr_heads = argc - i;
 371                break;
 372        }
 373        if (!dest)
 374                usage(send_pack_usage);
 375        if (heads && send_all)
 376                usage(send_pack_usage);
 377        pid = git_connect(fd, dest, exec);
 378        if (pid < 0)
 379                return 1;
 380        ret = send_pack(fd[0], fd[1], nr_heads, heads);
 381        close(fd[0]);
 382        close(fd[1]);
 383        finish_connect(pid);
 384        return ret;
 385}