Andrew's git / gitweb.git / receive-pack.c
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receive-pack.con commit cvsserver: Introduce new state variable 'method' (80573ba)
   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_unpack_limit = -1;
  14static int transfer_unpack_limit = -1;
  15static int unpack_limit = 100;
  16static int report_status;
  17
  18static char capabilities[] = " report-status delete-refs ";
  19static int capabilities_sent;
  20
  21static int receive_pack_config(const char *var, const char *value)
  22{
  23        if (strcmp(var, "receive.denynonfastforwards") == 0) {
  24                deny_non_fast_forwards = git_config_bool(var, value);
  25                return 0;
  26        }
  27
  28        if (strcmp(var, "receive.unpacklimit") == 0) {
  29                receive_unpack_limit = git_config_int(var, value);
  30                return 0;
  31        }
  32
  33        if (strcmp(var, "transfer.unpacklimit") == 0) {
  34                transfer_unpack_limit = git_config_int(var, value);
  35                return 0;
  36        }
  37
  38        return git_default_config(var, value);
  39}
  40
  41static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
  42{
  43        if (capabilities_sent)
  44                packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
  45        else
  46                packet_write(1, "%s %s%c%s\n",
  47                             sha1_to_hex(sha1), path, 0, capabilities);
  48        capabilities_sent = 1;
  49        return 0;
  50}
  51
  52static void write_head_info(void)
  53{
  54        for_each_ref(show_ref, NULL);
  55        if (!capabilities_sent)
  56                show_ref("capabilities^{}", null_sha1, 0, NULL);
  57
  58}
  59
  60struct command {
  61        struct command *next;
  62        const char *error_string;
  63        unsigned char old_sha1[20];
  64        unsigned char new_sha1[20];
  65        char ref_name[FLEX_ARRAY]; /* more */
  66};
  67
  68static struct command *commands;
  69
  70static const char pre_receive_hook[] = "hooks/pre-receive";
  71static const char post_receive_hook[] = "hooks/post-receive";
  72
  73static int hook_status(int code, const char *hook_name)
  74{
  75        switch (code) {
  76        case 0:
  77                return 0;
  78        case -ERR_RUN_COMMAND_FORK:
  79                return error("hook fork failed");
  80        case -ERR_RUN_COMMAND_EXEC:
  81                return error("hook execute failed");
  82        case -ERR_RUN_COMMAND_PIPE:
  83                return error("hook pipe failed");
  84        case -ERR_RUN_COMMAND_WAITPID:
  85                return error("waitpid failed");
  86        case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
  87                return error("waitpid is confused");
  88        case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
  89                return error("%s died of signal", hook_name);
  90        case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
  91                return error("%s died strangely", hook_name);
  92        default:
  93                error("%s exited with error code %d", hook_name, -code);
  94                return -code;
  95        }
  96}
  97
  98static int run_hook(const char *hook_name)
  99{
 100        static char buf[sizeof(commands->old_sha1) * 2 + PATH_MAX + 4];
 101        struct command *cmd;
 102        struct child_process proc;
 103        const char *argv[2];
 104        int have_input = 0, code;
 105
 106        for (cmd = commands; !have_input && cmd; cmd = cmd->next) {
 107                if (!cmd->error_string)
 108                        have_input = 1;
 109        }
 110
 111        if (!have_input || access(hook_name, X_OK) < 0)
 112                return 0;
 113
 114        argv[0] = hook_name;
 115        argv[1] = NULL;
 116
 117        memset(&proc, 0, sizeof(proc));
 118        proc.argv = argv;
 119        proc.in = -1;
 120        proc.stdout_to_stderr = 1;
 121
 122        code = start_command(&proc);
 123        if (code)
 124                return hook_status(code, hook_name);
 125        for (cmd = commands; cmd; cmd = cmd->next) {
 126                if (!cmd->error_string) {
 127                        size_t n = snprintf(buf, sizeof(buf), "%s %s %s\n",
 128                                sha1_to_hex(cmd->old_sha1),
 129                                sha1_to_hex(cmd->new_sha1),
 130                                cmd->ref_name);
 131                        if (write_in_full(proc.in, buf, n) != n)
 132                                break;
 133                }
 134        }
 135        return hook_status(finish_command(&proc), hook_name);
 136}
 137
 138static int run_update_hook(struct command *cmd)
 139{
 140        static const char update_hook[] = "hooks/update";
 141        struct child_process proc;
 142        const char *argv[5];
 143
 144        if (access(update_hook, X_OK) < 0)
 145                return 0;
 146
 147        argv[0] = update_hook;
 148        argv[1] = cmd->ref_name;
 149        argv[2] = sha1_to_hex(cmd->old_sha1);
 150        argv[3] = sha1_to_hex(cmd->new_sha1);
 151        argv[4] = NULL;
 152
 153        memset(&proc, 0, sizeof(proc));
 154        proc.argv = argv;
 155        proc.no_stdin = 1;
 156        proc.stdout_to_stderr = 1;
 157
 158        return hook_status(run_command(&proc), update_hook);
 159}
 160
 161static const char *update(struct command *cmd)
 162{
 163        const char *name = cmd->ref_name;
 164        unsigned char *old_sha1 = cmd->old_sha1;
 165        unsigned char *new_sha1 = cmd->new_sha1;
 166        struct ref_lock *lock;
 167
 168        if (!prefixcmp(name, "refs/") && check_ref_format(name + 5)) {
 169                error("refusing to create funny ref '%s' locally", name);
 170                return "funny refname";
 171        }
 172
 173        if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
 174                error("unpack should have generated %s, "
 175                      "but I can't find it!", sha1_to_hex(new_sha1));
 176                return "bad pack";
 177        }
 178        if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
 179            !is_null_sha1(old_sha1) &&
 180            !prefixcmp(name, "refs/heads/")) {
 181                struct commit *old_commit, *new_commit;
 182                struct commit_list *bases, *ent;
 183
 184                old_commit = (struct commit *)parse_object(old_sha1);
 185                new_commit = (struct commit *)parse_object(new_sha1);
 186                bases = get_merge_bases(old_commit, new_commit, 1);
 187                for (ent = bases; ent; ent = ent->next)
 188                        if (!hashcmp(old_sha1, ent->item->object.sha1))
 189                                break;
 190                free_commit_list(bases);
 191                if (!ent) {
 192                        error("denying non-fast forward %s"
 193                              " (you should pull first)", name);
 194                        return "non-fast forward";
 195                }
 196        }
 197        if (run_update_hook(cmd)) {
 198                error("hook declined to update %s", name);
 199                return "hook declined";
 200        }
 201
 202        if (is_null_sha1(new_sha1)) {
 203                if (delete_ref(name, old_sha1)) {
 204                        error("failed to delete %s", name);
 205                        return "failed to delete";
 206                }
 207                fprintf(stderr, "%s: %s -> deleted\n", name,
 208                        sha1_to_hex(old_sha1));
 209                return NULL; /* good */
 210        }
 211        else {
 212                lock = lock_any_ref_for_update(name, old_sha1);
 213                if (!lock) {
 214                        error("failed to lock %s", name);
 215                        return "failed to lock";
 216                }
 217                if (write_ref_sha1(lock, new_sha1, "push")) {
 218                        return "failed to write"; /* error() already called */
 219                }
 220                fprintf(stderr, "%s: %s -> %s\n", name,
 221                        sha1_to_hex(old_sha1), sha1_to_hex(new_sha1));
 222                return NULL; /* good */
 223        }
 224}
 225
 226static char update_post_hook[] = "hooks/post-update";
 227
 228static void run_update_post_hook(struct command *cmd)
 229{
 230        struct command *cmd_p;
 231        int argc;
 232        const char **argv;
 233
 234        for (argc = 0, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 235                if (cmd_p->error_string)
 236                        continue;
 237                argc++;
 238        }
 239        if (!argc || access(update_post_hook, X_OK) < 0)
 240                return;
 241        argv = xmalloc(sizeof(*argv) * (2 + argc));
 242        argv[0] = update_post_hook;
 243
 244        for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 245                char *p;
 246                if (cmd_p->error_string)
 247                        continue;
 248                p = xmalloc(strlen(cmd_p->ref_name) + 1);
 249                strcpy(p, cmd_p->ref_name);
 250                argv[argc] = p;
 251                argc++;
 252        }
 253        argv[argc] = NULL;
 254        run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
 255                | RUN_COMMAND_STDOUT_TO_STDERR);
 256}
 257
 258static void execute_commands(const char *unpacker_error)
 259{
 260        struct command *cmd = commands;
 261
 262        if (unpacker_error) {
 263                while (cmd) {
 264                        cmd->error_string = "n/a (unpacker error)";
 265                        cmd = cmd->next;
 266                }
 267                return;
 268        }
 269
 270        if (run_hook(pre_receive_hook)) {
 271                while (cmd) {
 272                        cmd->error_string = "pre-receive hook declined";
 273                        cmd = cmd->next;
 274                }
 275                return;
 276        }
 277
 278        while (cmd) {
 279                cmd->error_string = update(cmd);
 280                cmd = cmd->next;
 281        }
 282}
 283
 284static void read_head_info(void)
 285{
 286        struct command **p = &commands;
 287        for (;;) {
 288                static char line[1000];
 289                unsigned char old_sha1[20], new_sha1[20];
 290                struct command *cmd;
 291                char *refname;
 292                int len, reflen;
 293
 294                len = packet_read_line(0, line, sizeof(line));
 295                if (!len)
 296                        break;
 297                if (line[len-1] == '\n')
 298                        line[--len] = 0;
 299                if (len < 83 ||
 300                    line[40] != ' ' ||
 301                    line[81] != ' ' ||
 302                    get_sha1_hex(line, old_sha1) ||
 303                    get_sha1_hex(line + 41, new_sha1))
 304                        die("protocol error: expected old/new/ref, got '%s'",
 305                            line);
 306
 307                refname = line + 82;
 308                reflen = strlen(refname);
 309                if (reflen + 82 < len) {
 310                        if (strstr(refname + reflen + 1, "report-status"))
 311                                report_status = 1;
 312                }
 313                cmd = xmalloc(sizeof(struct command) + len - 80);
 314                hashcpy(cmd->old_sha1, old_sha1);
 315                hashcpy(cmd->new_sha1, new_sha1);
 316                memcpy(cmd->ref_name, line + 82, len - 81);
 317                cmd->error_string = NULL;
 318                cmd->next = NULL;
 319                *p = cmd;
 320                p = &cmd->next;
 321        }
 322}
 323
 324static const char *parse_pack_header(struct pack_header *hdr)
 325{
 326        switch (read_pack_header(0, hdr)) {
 327        case PH_ERROR_EOF:
 328                return "eof before pack header was fully read";
 329
 330        case PH_ERROR_PACK_SIGNATURE:
 331                return "protocol error (pack signature mismatch detected)";
 332
 333        case PH_ERROR_PROTOCOL:
 334                return "protocol error (pack version unsupported)";
 335
 336        default:
 337                return "unknown error in parse_pack_header";
 338
 339        case 0:
 340                return NULL;
 341        }
 342}
 343
 344static const char *pack_lockfile;
 345
 346static const char *unpack(void)
 347{
 348        struct pack_header hdr;
 349        const char *hdr_err;
 350        char hdr_arg[38];
 351
 352        hdr_err = parse_pack_header(&hdr);
 353        if (hdr_err)
 354                return hdr_err;
 355        snprintf(hdr_arg, sizeof(hdr_arg), "--pack_header=%u,%u",
 356                        ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
 357
 358        if (ntohl(hdr.hdr_entries) < unpack_limit) {
 359                int code;
 360                const char *unpacker[3];
 361                unpacker[0] = "unpack-objects";
 362                unpacker[1] = hdr_arg;
 363                unpacker[2] = NULL;
 364                code = run_command_v_opt(unpacker, RUN_GIT_CMD);
 365                switch (code) {
 366                case 0:
 367                        return NULL;
 368                case -ERR_RUN_COMMAND_FORK:
 369                        return "unpack fork failed";
 370                case -ERR_RUN_COMMAND_EXEC:
 371                        return "unpack execute failed";
 372                case -ERR_RUN_COMMAND_WAITPID:
 373                        return "waitpid failed";
 374                case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 375                        return "waitpid is confused";
 376                case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 377                        return "unpacker died of signal";
 378                case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 379                        return "unpacker died strangely";
 380                default:
 381                        return "unpacker exited with error code";
 382                }
 383        } else {
 384                const char *keeper[6];
 385                int s, len, status;
 386                char keep_arg[256];
 387                char packname[46];
 388                struct child_process ip;
 389
 390                s = sprintf(keep_arg, "--keep=receive-pack %i on ", getpid());
 391                if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
 392                        strcpy(keep_arg + s, "localhost");
 393
 394                keeper[0] = "index-pack";
 395                keeper[1] = "--stdin";
 396                keeper[2] = "--fix-thin";
 397                keeper[3] = hdr_arg;
 398                keeper[4] = keep_arg;
 399                keeper[5] = NULL;
 400                memset(&ip, 0, sizeof(ip));
 401                ip.argv = keeper;
 402                ip.out = -1;
 403                ip.git_cmd = 1;
 404                if (start_command(&ip))
 405                        return "index-pack fork failed";
 406
 407                /*
 408                 * The first thing we expects from index-pack's output
 409                 * is "pack\t%40s\n" or "keep\t%40s\n" (46 bytes) where
 410                 * %40s is the newly created pack SHA1 name.  In the "keep"
 411                 * case, we need it to remove the corresponding .keep file
 412                 * later on.  If we don't get that then tough luck with it.
 413                 */
 414                for (len = 0;
 415                     len < 46 && (s = xread(ip.out, packname+len, 46-len)) > 0;
 416                     len += s);
 417                if (len == 46 && packname[45] == '\n' &&
 418                    memcmp(packname, "keep\t", 5) == 0) {
 419                        char path[PATH_MAX];
 420                        packname[45] = 0;
 421                        snprintf(path, sizeof(path), "%s/pack/pack-%s.keep",
 422                                 get_object_directory(), packname + 5);
 423                        pack_lockfile = xstrdup(path);
 424                }
 425
 426                status = finish_command(&ip);
 427                if (!status) {
 428                        reprepare_packed_git();
 429                        return NULL;
 430                }
 431                return "index-pack abnormal exit";
 432        }
 433}
 434
 435static void report(const char *unpack_status)
 436{
 437        struct command *cmd;
 438        packet_write(1, "unpack %s\n",
 439                     unpack_status ? unpack_status : "ok");
 440        for (cmd = commands; cmd; cmd = cmd->next) {
 441                if (!cmd->error_string)
 442                        packet_write(1, "ok %s\n",
 443                                     cmd->ref_name);
 444                else
 445                        packet_write(1, "ng %s %s\n",
 446                                     cmd->ref_name, cmd->error_string);
 447        }
 448        packet_flush(1);
 449}
 450
 451static int delete_only(struct command *cmd)
 452{
 453        while (cmd) {
 454                if (!is_null_sha1(cmd->new_sha1))
 455                        return 0;
 456                cmd = cmd->next;
 457        }
 458        return 1;
 459}
 460
 461int main(int argc, char **argv)
 462{
 463        int i;
 464        char *dir = NULL;
 465
 466        argv++;
 467        for (i = 1; i < argc; i++) {
 468                char *arg = *argv++;
 469
 470                if (*arg == '-') {
 471                        /* Do flag handling here */
 472                        usage(receive_pack_usage);
 473                }
 474                if (dir)
 475                        usage(receive_pack_usage);
 476                dir = arg;
 477        }
 478        if (!dir)
 479                usage(receive_pack_usage);
 480
 481        if (!enter_repo(dir, 0))
 482                die("'%s': unable to chdir or not a git archive", dir);
 483
 484        if (is_repository_shallow())
 485                die("attempt to push into a shallow repository");
 486
 487        git_config(receive_pack_config);
 488
 489        if (0 <= transfer_unpack_limit)
 490                unpack_limit = transfer_unpack_limit;
 491        else if (0 <= receive_unpack_limit)
 492                unpack_limit = receive_unpack_limit;
 493
 494        write_head_info();
 495
 496        /* EOF */
 497        packet_flush(1);
 498
 499        read_head_info();
 500        if (commands) {
 501                const char *unpack_status = NULL;
 502
 503                if (!delete_only(commands))
 504                        unpack_status = unpack();
 505                execute_commands(unpack_status);
 506                if (pack_lockfile)
 507                        unlink(pack_lockfile);
 508                if (report_status)
 509                        report(unpack_status);
 510                run_hook(post_receive_hook);
 511                run_update_post_hook(commands);
 512        }
 513        return 0;
 514}