receive-pack.con commit describe: match pattern for lightweight tags too (4ed19a3)
   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        close(proc.in);
 136        return hook_status(finish_command(&proc), hook_name);
 137}
 138
 139static int run_update_hook(struct command *cmd)
 140{
 141        static const char update_hook[] = "hooks/update";
 142        struct child_process proc;
 143        const char *argv[5];
 144
 145        if (access(update_hook, X_OK) < 0)
 146                return 0;
 147
 148        argv[0] = update_hook;
 149        argv[1] = cmd->ref_name;
 150        argv[2] = sha1_to_hex(cmd->old_sha1);
 151        argv[3] = sha1_to_hex(cmd->new_sha1);
 152        argv[4] = NULL;
 153
 154        memset(&proc, 0, sizeof(proc));
 155        proc.argv = argv;
 156        proc.no_stdin = 1;
 157        proc.stdout_to_stderr = 1;
 158
 159        return hook_status(run_command(&proc), update_hook);
 160}
 161
 162static const char *update(struct command *cmd)
 163{
 164        const char *name = cmd->ref_name;
 165        unsigned char *old_sha1 = cmd->old_sha1;
 166        unsigned char *new_sha1 = cmd->new_sha1;
 167        struct ref_lock *lock;
 168
 169        /* only refs/... are allowed */
 170        if (prefixcmp(name, "refs/") || check_ref_format(name + 5)) {
 171                error("refusing to create funny ref '%s' remotely", name);
 172                return "funny refname";
 173        }
 174
 175        if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
 176                error("unpack should have generated %s, "
 177                      "but I can't find it!", sha1_to_hex(new_sha1));
 178                return "bad pack";
 179        }
 180        if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
 181            !is_null_sha1(old_sha1) &&
 182            !prefixcmp(name, "refs/heads/")) {
 183                struct object *old_object, *new_object;
 184                struct commit *old_commit, *new_commit;
 185                struct commit_list *bases, *ent;
 186
 187                old_object = parse_object(old_sha1);
 188                new_object = parse_object(new_sha1);
 189
 190                if (!old_object || !new_object ||
 191                    old_object->type != OBJ_COMMIT ||
 192                    new_object->type != OBJ_COMMIT) {
 193                        error("bad sha1 objects for %s", name);
 194                        return "bad ref";
 195                }
 196                old_commit = (struct commit *)old_object;
 197                new_commit = (struct commit *)new_object;
 198                bases = get_merge_bases(old_commit, new_commit, 1);
 199                for (ent = bases; ent; ent = ent->next)
 200                        if (!hashcmp(old_sha1, ent->item->object.sha1))
 201                                break;
 202                free_commit_list(bases);
 203                if (!ent) {
 204                        error("denying non-fast forward %s"
 205                              " (you should pull first)", name);
 206                        return "non-fast forward";
 207                }
 208        }
 209        if (run_update_hook(cmd)) {
 210                error("hook declined to update %s", name);
 211                return "hook declined";
 212        }
 213
 214        if (is_null_sha1(new_sha1)) {
 215                if (!parse_object(old_sha1)) {
 216                        warning ("Allowing deletion of corrupt ref.");
 217                        old_sha1 = NULL;
 218                }
 219                if (delete_ref(name, old_sha1)) {
 220                        error("failed to delete %s", name);
 221                        return "failed to delete";
 222                }
 223                return NULL; /* good */
 224        }
 225        else {
 226                lock = lock_any_ref_for_update(name, old_sha1, 0);
 227                if (!lock) {
 228                        error("failed to lock %s", name);
 229                        return "failed to lock";
 230                }
 231                if (write_ref_sha1(lock, new_sha1, "push")) {
 232                        return "failed to write"; /* error() already called */
 233                }
 234                return NULL; /* good */
 235        }
 236}
 237
 238static char update_post_hook[] = "hooks/post-update";
 239
 240static void run_update_post_hook(struct command *cmd)
 241{
 242        struct command *cmd_p;
 243        int argc;
 244        const char **argv;
 245
 246        for (argc = 0, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 247                if (cmd_p->error_string)
 248                        continue;
 249                argc++;
 250        }
 251        if (!argc || access(update_post_hook, X_OK) < 0)
 252                return;
 253        argv = xmalloc(sizeof(*argv) * (2 + argc));
 254        argv[0] = update_post_hook;
 255
 256        for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 257                char *p;
 258                if (cmd_p->error_string)
 259                        continue;
 260                p = xmalloc(strlen(cmd_p->ref_name) + 1);
 261                strcpy(p, cmd_p->ref_name);
 262                argv[argc] = p;
 263                argc++;
 264        }
 265        argv[argc] = NULL;
 266        run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
 267                | RUN_COMMAND_STDOUT_TO_STDERR);
 268}
 269
 270static void execute_commands(const char *unpacker_error)
 271{
 272        struct command *cmd = commands;
 273
 274        if (unpacker_error) {
 275                while (cmd) {
 276                        cmd->error_string = "n/a (unpacker error)";
 277                        cmd = cmd->next;
 278                }
 279                return;
 280        }
 281
 282        if (run_hook(pre_receive_hook)) {
 283                while (cmd) {
 284                        cmd->error_string = "pre-receive hook declined";
 285                        cmd = cmd->next;
 286                }
 287                return;
 288        }
 289
 290        while (cmd) {
 291                cmd->error_string = update(cmd);
 292                cmd = cmd->next;
 293        }
 294}
 295
 296static void read_head_info(void)
 297{
 298        struct command **p = &commands;
 299        for (;;) {
 300                static char line[1000];
 301                unsigned char old_sha1[20], new_sha1[20];
 302                struct command *cmd;
 303                char *refname;
 304                int len, reflen;
 305
 306                len = packet_read_line(0, line, sizeof(line));
 307                if (!len)
 308                        break;
 309                if (line[len-1] == '\n')
 310                        line[--len] = 0;
 311                if (len < 83 ||
 312                    line[40] != ' ' ||
 313                    line[81] != ' ' ||
 314                    get_sha1_hex(line, old_sha1) ||
 315                    get_sha1_hex(line + 41, new_sha1))
 316                        die("protocol error: expected old/new/ref, got '%s'",
 317                            line);
 318
 319                refname = line + 82;
 320                reflen = strlen(refname);
 321                if (reflen + 82 < len) {
 322                        if (strstr(refname + reflen + 1, "report-status"))
 323                                report_status = 1;
 324                }
 325                cmd = xmalloc(sizeof(struct command) + len - 80);
 326                hashcpy(cmd->old_sha1, old_sha1);
 327                hashcpy(cmd->new_sha1, new_sha1);
 328                memcpy(cmd->ref_name, line + 82, len - 81);
 329                cmd->error_string = NULL;
 330                cmd->next = NULL;
 331                *p = cmd;
 332                p = &cmd->next;
 333        }
 334}
 335
 336static const char *parse_pack_header(struct pack_header *hdr)
 337{
 338        switch (read_pack_header(0, hdr)) {
 339        case PH_ERROR_EOF:
 340                return "eof before pack header was fully read";
 341
 342        case PH_ERROR_PACK_SIGNATURE:
 343                return "protocol error (pack signature mismatch detected)";
 344
 345        case PH_ERROR_PROTOCOL:
 346                return "protocol error (pack version unsupported)";
 347
 348        default:
 349                return "unknown error in parse_pack_header";
 350
 351        case 0:
 352                return NULL;
 353        }
 354}
 355
 356static const char *pack_lockfile;
 357
 358static const char *unpack(void)
 359{
 360        struct pack_header hdr;
 361        const char *hdr_err;
 362        char hdr_arg[38];
 363
 364        hdr_err = parse_pack_header(&hdr);
 365        if (hdr_err)
 366                return hdr_err;
 367        snprintf(hdr_arg, sizeof(hdr_arg), "--pack_header=%u,%u",
 368                        ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
 369
 370        if (ntohl(hdr.hdr_entries) < unpack_limit) {
 371                int code;
 372                const char *unpacker[3];
 373                unpacker[0] = "unpack-objects";
 374                unpacker[1] = hdr_arg;
 375                unpacker[2] = NULL;
 376                code = run_command_v_opt(unpacker, RUN_GIT_CMD);
 377                switch (code) {
 378                case 0:
 379                        return NULL;
 380                case -ERR_RUN_COMMAND_FORK:
 381                        return "unpack fork failed";
 382                case -ERR_RUN_COMMAND_EXEC:
 383                        return "unpack execute failed";
 384                case -ERR_RUN_COMMAND_WAITPID:
 385                        return "waitpid failed";
 386                case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 387                        return "waitpid is confused";
 388                case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 389                        return "unpacker died of signal";
 390                case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 391                        return "unpacker died strangely";
 392                default:
 393                        return "unpacker exited with error code";
 394                }
 395        } else {
 396                const char *keeper[6];
 397                int s, status;
 398                char keep_arg[256];
 399                struct child_process ip;
 400
 401                s = sprintf(keep_arg, "--keep=receive-pack %i on ", getpid());
 402                if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
 403                        strcpy(keep_arg + s, "localhost");
 404
 405                keeper[0] = "index-pack";
 406                keeper[1] = "--stdin";
 407                keeper[2] = "--fix-thin";
 408                keeper[3] = hdr_arg;
 409                keeper[4] = keep_arg;
 410                keeper[5] = NULL;
 411                memset(&ip, 0, sizeof(ip));
 412                ip.argv = keeper;
 413                ip.out = -1;
 414                ip.git_cmd = 1;
 415                if (start_command(&ip))
 416                        return "index-pack fork failed";
 417                pack_lockfile = index_pack_lockfile(ip.out);
 418                close(ip.out);
 419                status = finish_command(&ip);
 420                if (!status) {
 421                        reprepare_packed_git();
 422                        return NULL;
 423                }
 424                return "index-pack abnormal exit";
 425        }
 426}
 427
 428static void report(const char *unpack_status)
 429{
 430        struct command *cmd;
 431        packet_write(1, "unpack %s\n",
 432                     unpack_status ? unpack_status : "ok");
 433        for (cmd = commands; cmd; cmd = cmd->next) {
 434                if (!cmd->error_string)
 435                        packet_write(1, "ok %s\n",
 436                                     cmd->ref_name);
 437                else
 438                        packet_write(1, "ng %s %s\n",
 439                                     cmd->ref_name, cmd->error_string);
 440        }
 441        packet_flush(1);
 442}
 443
 444static int delete_only(struct command *cmd)
 445{
 446        while (cmd) {
 447                if (!is_null_sha1(cmd->new_sha1))
 448                        return 0;
 449                cmd = cmd->next;
 450        }
 451        return 1;
 452}
 453
 454int main(int argc, char **argv)
 455{
 456        int i;
 457        char *dir = NULL;
 458
 459        argv++;
 460        for (i = 1; i < argc; i++) {
 461                char *arg = *argv++;
 462
 463                if (*arg == '-') {
 464                        /* Do flag handling here */
 465                        usage(receive_pack_usage);
 466                }
 467                if (dir)
 468                        usage(receive_pack_usage);
 469                dir = arg;
 470        }
 471        if (!dir)
 472                usage(receive_pack_usage);
 473
 474        setup_path(NULL);
 475
 476        if (!enter_repo(dir, 0))
 477                die("'%s': unable to chdir or not a git archive", dir);
 478
 479        if (is_repository_shallow())
 480                die("attempt to push into a shallow repository");
 481
 482        git_config(receive_pack_config);
 483
 484        if (0 <= transfer_unpack_limit)
 485                unpack_limit = transfer_unpack_limit;
 486        else if (0 <= receive_unpack_limit)
 487                unpack_limit = receive_unpack_limit;
 488
 489        write_head_info();
 490
 491        /* EOF */
 492        packet_flush(1);
 493
 494        read_head_info();
 495        if (commands) {
 496                const char *unpack_status = NULL;
 497
 498                if (!delete_only(commands))
 499                        unpack_status = unpack();
 500                execute_commands(unpack_status);
 501                if (pack_lockfile)
 502                        unlink(pack_lockfile);
 503                if (report_status)
 504                        report(unpack_status);
 505                run_hook(post_receive_hook);
 506                run_update_post_hook(commands);
 507        }
 508        return 0;
 509}