Andrew's git / gitweb.git / receive-pack.c
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receive-pack.con commit Make old sha1 optional with git update-ref -d (3fe8dce)
   1#include "cache.h"
   2#include "pack.h"
   3#include "refs.h"
   4#include "pkt-line.h"
   5#include "run-command.h"
   6#include "exec_cmd.h"
   7#include "commit.h"
   8#include "object.h"
   9
  10static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
  11
  12static int deny_non_fast_forwards = 0;
  13static int receive_fsck_objects;
  14static int receive_unpack_limit = -1;
  15static int transfer_unpack_limit = -1;
  16static int unpack_limit = 100;
  17static int report_status;
  18
  19static char capabilities[] = " report-status delete-refs ";
  20static int capabilities_sent;
  21
  22static int receive_pack_config(const char *var, const char *value, void *cb)
  23{
  24        if (strcmp(var, "receive.denynonfastforwards") == 0) {
  25                deny_non_fast_forwards = git_config_bool(var, value);
  26                return 0;
  27        }
  28
  29        if (strcmp(var, "receive.unpacklimit") == 0) {
  30                receive_unpack_limit = git_config_int(var, value);
  31                return 0;
  32        }
  33
  34        if (strcmp(var, "transfer.unpacklimit") == 0) {
  35                transfer_unpack_limit = git_config_int(var, value);
  36                return 0;
  37        }
  38
  39        if (strcmp(var, "receive.fsckobjects") == 0) {
  40                receive_fsck_objects = git_config_bool(var, value);
  41                return 0;
  42        }
  43
  44        return git_default_config(var, value, cb);
  45}
  46
  47static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
  48{
  49        if (capabilities_sent)
  50                packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
  51        else
  52                packet_write(1, "%s %s%c%s\n",
  53                             sha1_to_hex(sha1), path, 0, capabilities);
  54        capabilities_sent = 1;
  55        return 0;
  56}
  57
  58static void write_head_info(void)
  59{
  60        for_each_ref(show_ref, NULL);
  61        if (!capabilities_sent)
  62                show_ref("capabilities^{}", null_sha1, 0, NULL);
  63
  64}
  65
  66struct command {
  67        struct command *next;
  68        const char *error_string;
  69        unsigned char old_sha1[20];
  70        unsigned char new_sha1[20];
  71        char ref_name[FLEX_ARRAY]; /* more */
  72};
  73
  74static struct command *commands;
  75
  76static const char pre_receive_hook[] = "hooks/pre-receive";
  77static const char post_receive_hook[] = "hooks/post-receive";
  78
  79static int hook_status(int code, const char *hook_name)
  80{
  81        switch (code) {
  82        case 0:
  83                return 0;
  84        case -ERR_RUN_COMMAND_FORK:
  85                return error("hook fork failed");
  86        case -ERR_RUN_COMMAND_EXEC:
  87                return error("hook execute failed");
  88        case -ERR_RUN_COMMAND_PIPE:
  89                return error("hook pipe failed");
  90        case -ERR_RUN_COMMAND_WAITPID:
  91                return error("waitpid failed");
  92        case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
  93                return error("waitpid is confused");
  94        case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
  95                return error("%s died of signal", hook_name);
  96        case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
  97                return error("%s died strangely", hook_name);
  98        default:
  99                error("%s exited with error code %d", hook_name, -code);
 100                return -code;
 101        }
 102}
 103
 104static int run_hook(const char *hook_name)
 105{
 106        static char buf[sizeof(commands->old_sha1) * 2 + PATH_MAX + 4];
 107        struct command *cmd;
 108        struct child_process proc;
 109        const char *argv[2];
 110        int have_input = 0, code;
 111
 112        for (cmd = commands; !have_input && cmd; cmd = cmd->next) {
 113                if (!cmd->error_string)
 114                        have_input = 1;
 115        }
 116
 117        if (!have_input || access(hook_name, X_OK) < 0)
 118                return 0;
 119
 120        argv[0] = hook_name;
 121        argv[1] = NULL;
 122
 123        memset(&proc, 0, sizeof(proc));
 124        proc.argv = argv;
 125        proc.in = -1;
 126        proc.stdout_to_stderr = 1;
 127
 128        code = start_command(&proc);
 129        if (code)
 130                return hook_status(code, hook_name);
 131        for (cmd = commands; cmd; cmd = cmd->next) {
 132                if (!cmd->error_string) {
 133                        size_t n = snprintf(buf, sizeof(buf), "%s %s %s\n",
 134                                sha1_to_hex(cmd->old_sha1),
 135                                sha1_to_hex(cmd->new_sha1),
 136                                cmd->ref_name);
 137                        if (write_in_full(proc.in, buf, n) != n)
 138                                break;
 139                }
 140        }
 141        close(proc.in);
 142        return hook_status(finish_command(&proc), hook_name);
 143}
 144
 145static int run_update_hook(struct command *cmd)
 146{
 147        static const char update_hook[] = "hooks/update";
 148        struct child_process proc;
 149        const char *argv[5];
 150
 151        if (access(update_hook, X_OK) < 0)
 152                return 0;
 153
 154        argv[0] = update_hook;
 155        argv[1] = cmd->ref_name;
 156        argv[2] = sha1_to_hex(cmd->old_sha1);
 157        argv[3] = sha1_to_hex(cmd->new_sha1);
 158        argv[4] = NULL;
 159
 160        memset(&proc, 0, sizeof(proc));
 161        proc.argv = argv;
 162        proc.no_stdin = 1;
 163        proc.stdout_to_stderr = 1;
 164
 165        return hook_status(run_command(&proc), update_hook);
 166}
 167
 168static const char *update(struct command *cmd)
 169{
 170        const char *name = cmd->ref_name;
 171        unsigned char *old_sha1 = cmd->old_sha1;
 172        unsigned char *new_sha1 = cmd->new_sha1;
 173        struct ref_lock *lock;
 174
 175        /* only refs/... are allowed */
 176        if (prefixcmp(name, "refs/") || check_ref_format(name + 5)) {
 177                error("refusing to create funny ref '%s' remotely", name);
 178                return "funny refname";
 179        }
 180
 181        if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
 182                error("unpack should have generated %s, "
 183                      "but I can't find it!", sha1_to_hex(new_sha1));
 184                return "bad pack";
 185        }
 186        if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
 187            !is_null_sha1(old_sha1) &&
 188            !prefixcmp(name, "refs/heads/")) {
 189                struct object *old_object, *new_object;
 190                struct commit *old_commit, *new_commit;
 191                struct commit_list *bases, *ent;
 192
 193                old_object = parse_object(old_sha1);
 194                new_object = parse_object(new_sha1);
 195
 196                if (!old_object || !new_object ||
 197                    old_object->type != OBJ_COMMIT ||
 198                    new_object->type != OBJ_COMMIT) {
 199                        error("bad sha1 objects for %s", name);
 200                        return "bad ref";
 201                }
 202                old_commit = (struct commit *)old_object;
 203                new_commit = (struct commit *)new_object;
 204                bases = get_merge_bases(old_commit, new_commit, 1);
 205                for (ent = bases; ent; ent = ent->next)
 206                        if (!hashcmp(old_sha1, ent->item->object.sha1))
 207                                break;
 208                free_commit_list(bases);
 209                if (!ent) {
 210                        error("denying non-fast forward %s"
 211                              " (you should pull first)", name);
 212                        return "non-fast forward";
 213                }
 214        }
 215        if (run_update_hook(cmd)) {
 216                error("hook declined to update %s", name);
 217                return "hook declined";
 218        }
 219
 220        if (is_null_sha1(new_sha1)) {
 221                if (!parse_object(old_sha1)) {
 222                        warning ("Allowing deletion of corrupt ref.");
 223                        old_sha1 = NULL;
 224                }
 225                if (delete_ref(name, old_sha1)) {
 226                        error("failed to delete %s", name);
 227                        return "failed to delete";
 228                }
 229                return NULL; /* good */
 230        }
 231        else {
 232                lock = lock_any_ref_for_update(name, old_sha1, 0);
 233                if (!lock) {
 234                        error("failed to lock %s", name);
 235                        return "failed to lock";
 236                }
 237                if (write_ref_sha1(lock, new_sha1, "push")) {
 238                        return "failed to write"; /* error() already called */
 239                }
 240                return NULL; /* good */
 241        }
 242}
 243
 244static char update_post_hook[] = "hooks/post-update";
 245
 246static void run_update_post_hook(struct command *cmd)
 247{
 248        struct command *cmd_p;
 249        int argc;
 250        const char **argv;
 251
 252        for (argc = 0, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 253                if (cmd_p->error_string)
 254                        continue;
 255                argc++;
 256        }
 257        if (!argc || access(update_post_hook, X_OK) < 0)
 258                return;
 259        argv = xmalloc(sizeof(*argv) * (2 + argc));
 260        argv[0] = update_post_hook;
 261
 262        for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 263                char *p;
 264                if (cmd_p->error_string)
 265                        continue;
 266                p = xmalloc(strlen(cmd_p->ref_name) + 1);
 267                strcpy(p, cmd_p->ref_name);
 268                argv[argc] = p;
 269                argc++;
 270        }
 271        argv[argc] = NULL;
 272        run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
 273                | RUN_COMMAND_STDOUT_TO_STDERR);
 274}
 275
 276static void execute_commands(const char *unpacker_error)
 277{
 278        struct command *cmd = commands;
 279
 280        if (unpacker_error) {
 281                while (cmd) {
 282                        cmd->error_string = "n/a (unpacker error)";
 283                        cmd = cmd->next;
 284                }
 285                return;
 286        }
 287
 288        if (run_hook(pre_receive_hook)) {
 289                while (cmd) {
 290                        cmd->error_string = "pre-receive hook declined";
 291                        cmd = cmd->next;
 292                }
 293                return;
 294        }
 295
 296        while (cmd) {
 297                cmd->error_string = update(cmd);
 298                cmd = cmd->next;
 299        }
 300}
 301
 302static void read_head_info(void)
 303{
 304        struct command **p = &commands;
 305        for (;;) {
 306                static char line[1000];
 307                unsigned char old_sha1[20], new_sha1[20];
 308                struct command *cmd;
 309                char *refname;
 310                int len, reflen;
 311
 312                len = packet_read_line(0, line, sizeof(line));
 313                if (!len)
 314                        break;
 315                if (line[len-1] == '\n')
 316                        line[--len] = 0;
 317                if (len < 83 ||
 318                    line[40] != ' ' ||
 319                    line[81] != ' ' ||
 320                    get_sha1_hex(line, old_sha1) ||
 321                    get_sha1_hex(line + 41, new_sha1))
 322                        die("protocol error: expected old/new/ref, got '%s'",
 323                            line);
 324
 325                refname = line + 82;
 326                reflen = strlen(refname);
 327                if (reflen + 82 < len) {
 328                        if (strstr(refname + reflen + 1, "report-status"))
 329                                report_status = 1;
 330                }
 331                cmd = xmalloc(sizeof(struct command) + len - 80);
 332                hashcpy(cmd->old_sha1, old_sha1);
 333                hashcpy(cmd->new_sha1, new_sha1);
 334                memcpy(cmd->ref_name, line + 82, len - 81);
 335                cmd->error_string = NULL;
 336                cmd->next = NULL;
 337                *p = cmd;
 338                p = &cmd->next;
 339        }
 340}
 341
 342static const char *parse_pack_header(struct pack_header *hdr)
 343{
 344        switch (read_pack_header(0, hdr)) {
 345        case PH_ERROR_EOF:
 346                return "eof before pack header was fully read";
 347
 348        case PH_ERROR_PACK_SIGNATURE:
 349                return "protocol error (pack signature mismatch detected)";
 350
 351        case PH_ERROR_PROTOCOL:
 352                return "protocol error (pack version unsupported)";
 353
 354        default:
 355                return "unknown error in parse_pack_header";
 356
 357        case 0:
 358                return NULL;
 359        }
 360}
 361
 362static const char *pack_lockfile;
 363
 364static const char *unpack(void)
 365{
 366        struct pack_header hdr;
 367        const char *hdr_err;
 368        char hdr_arg[38];
 369
 370        hdr_err = parse_pack_header(&hdr);
 371        if (hdr_err)
 372                return hdr_err;
 373        snprintf(hdr_arg, sizeof(hdr_arg), "--pack_header=%u,%u",
 374                        ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
 375
 376        if (ntohl(hdr.hdr_entries) < unpack_limit) {
 377                int code, i = 0;
 378                const char *unpacker[4];
 379                unpacker[i++] = "unpack-objects";
 380                if (receive_fsck_objects)
 381                        unpacker[i++] = "--strict";
 382                unpacker[i++] = hdr_arg;
 383                unpacker[i++] = NULL;
 384                code = run_command_v_opt(unpacker, RUN_GIT_CMD);
 385                switch (code) {
 386                case 0:
 387                        return NULL;
 388                case -ERR_RUN_COMMAND_FORK:
 389                        return "unpack fork failed";
 390                case -ERR_RUN_COMMAND_EXEC:
 391                        return "unpack execute failed";
 392                case -ERR_RUN_COMMAND_WAITPID:
 393                        return "waitpid failed";
 394                case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 395                        return "waitpid is confused";
 396                case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 397                        return "unpacker died of signal";
 398                case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 399                        return "unpacker died strangely";
 400                default:
 401                        return "unpacker exited with error code";
 402                }
 403        } else {
 404                const char *keeper[7];
 405                int s, status, i = 0;
 406                char keep_arg[256];
 407                struct child_process ip;
 408
 409                s = sprintf(keep_arg, "--keep=receive-pack %i on ", getpid());
 410                if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
 411                        strcpy(keep_arg + s, "localhost");
 412
 413                keeper[i++] = "index-pack";
 414                keeper[i++] = "--stdin";
 415                if (receive_fsck_objects)
 416                        keeper[i++] = "--strict";
 417                keeper[i++] = "--fix-thin";
 418                keeper[i++] = hdr_arg;
 419                keeper[i++] = keep_arg;
 420                keeper[i++] = NULL;
 421                memset(&ip, 0, sizeof(ip));
 422                ip.argv = keeper;
 423                ip.out = -1;
 424                ip.git_cmd = 1;
 425                if (start_command(&ip))
 426                        return "index-pack fork failed";
 427                pack_lockfile = index_pack_lockfile(ip.out);
 428                close(ip.out);
 429                status = finish_command(&ip);
 430                if (!status) {
 431                        reprepare_packed_git();
 432                        return NULL;
 433                }
 434                return "index-pack abnormal exit";
 435        }
 436}
 437
 438static void report(const char *unpack_status)
 439{
 440        struct command *cmd;
 441        packet_write(1, "unpack %s\n",
 442                     unpack_status ? unpack_status : "ok");
 443        for (cmd = commands; cmd; cmd = cmd->next) {
 444                if (!cmd->error_string)
 445                        packet_write(1, "ok %s\n",
 446                                     cmd->ref_name);
 447                else
 448                        packet_write(1, "ng %s %s\n",
 449                                     cmd->ref_name, cmd->error_string);
 450        }
 451        packet_flush(1);
 452}
 453
 454static int delete_only(struct command *cmd)
 455{
 456        while (cmd) {
 457                if (!is_null_sha1(cmd->new_sha1))
 458                        return 0;
 459                cmd = cmd->next;
 460        }
 461        return 1;
 462}
 463
 464int main(int argc, char **argv)
 465{
 466        int i;
 467        char *dir = NULL;
 468
 469        argv++;
 470        for (i = 1; i < argc; i++) {
 471                char *arg = *argv++;
 472
 473                if (*arg == '-') {
 474                        /* Do flag handling here */
 475                        usage(receive_pack_usage);
 476                }
 477                if (dir)
 478                        usage(receive_pack_usage);
 479                dir = arg;
 480        }
 481        if (!dir)
 482                usage(receive_pack_usage);
 483
 484        setup_path(NULL);
 485
 486        if (!enter_repo(dir, 0))
 487                die("'%s': unable to chdir or not a git archive", dir);
 488
 489        if (is_repository_shallow())
 490                die("attempt to push into a shallow repository");
 491
 492        git_config(receive_pack_config, NULL);
 493
 494        if (0 <= transfer_unpack_limit)
 495                unpack_limit = transfer_unpack_limit;
 496        else if (0 <= receive_unpack_limit)
 497                unpack_limit = receive_unpack_limit;
 498
 499        write_head_info();
 500
 501        /* EOF */
 502        packet_flush(1);
 503
 504        read_head_info();
 505        if (commands) {
 506                const char *unpack_status = NULL;
 507
 508                if (!delete_only(commands))
 509                        unpack_status = unpack();
 510                execute_commands(unpack_status);
 511                if (pack_lockfile)
 512                        unlink(pack_lockfile);
 513                if (report_status)
 514                        report(unpack_status);
 515                run_hook(post_receive_hook);
 516                run_update_post_hook(commands);
 517        }
 518        return 0;
 519}