Andrew's git / gitweb.git / receive-pack.c
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receive-pack.con commit Merge branch 'js/attach' (8a3fbdd)
   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 update_hook[] = "hooks/update";
  71static const char pre_receive_hook[] = "hooks/pre-receive";
  72static const char post_receive_hook[] = "hooks/post-receive";
  73
  74static int run_hook(const char *hook_name,
  75        struct command *first_cmd,
  76        int single)
  77{
  78        struct command *cmd;
  79        int argc, code;
  80        const char **argv;
  81
  82        for (argc = 0, cmd = first_cmd; cmd; cmd = cmd->next) {
  83                if (!cmd->error_string)
  84                        argc += 3;
  85                if (single)
  86                        break;
  87        }
  88
  89        if (!argc || access(hook_name, X_OK) < 0)
  90                return 0;
  91
  92        argv = xmalloc(sizeof(*argv) * (2 + argc));
  93        argv[0] = hook_name;
  94        for (argc = 1, cmd = first_cmd; cmd; cmd = cmd->next) {
  95                if (!cmd->error_string) {
  96                        argv[argc++] = xstrdup(cmd->ref_name);
  97                        argv[argc++] = xstrdup(sha1_to_hex(cmd->old_sha1));
  98                        argv[argc++] = xstrdup(sha1_to_hex(cmd->new_sha1));
  99                }
 100                if (single)
 101                        break;
 102        }
 103        argv[argc] = NULL;
 104
 105        code = run_command_v_opt(argv,
 106                RUN_COMMAND_NO_STDIN | RUN_COMMAND_STDOUT_TO_STDERR);
 107        while (--argc > 0)
 108                free((char*)argv[argc]);
 109        free(argv);
 110
 111        switch (code) {
 112        case 0:
 113                return 0;
 114        case -ERR_RUN_COMMAND_FORK:
 115                return error("hook fork failed");
 116        case -ERR_RUN_COMMAND_EXEC:
 117                return error("hook execute failed");
 118        case -ERR_RUN_COMMAND_WAITPID:
 119                return error("waitpid failed");
 120        case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 121                return error("waitpid is confused");
 122        case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 123                return error("%s died of signal", hook_name);
 124        case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 125                return error("%s died strangely", hook_name);
 126        default:
 127                error("%s exited with error code %d", hook_name, -code);
 128                return -code;
 129        }
 130}
 131
 132static const char *update(struct command *cmd)
 133{
 134        const char *name = cmd->ref_name;
 135        unsigned char *old_sha1 = cmd->old_sha1;
 136        unsigned char *new_sha1 = cmd->new_sha1;
 137        struct ref_lock *lock;
 138
 139        if (!prefixcmp(name, "refs/") && check_ref_format(name + 5)) {
 140                error("refusing to create funny ref '%s' locally", name);
 141                return "funny refname";
 142        }
 143
 144        if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
 145                error("unpack should have generated %s, "
 146                      "but I can't find it!", sha1_to_hex(new_sha1));
 147                return "bad pack";
 148        }
 149        if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
 150            !is_null_sha1(old_sha1) &&
 151            !prefixcmp(name, "refs/heads/")) {
 152                struct commit *old_commit, *new_commit;
 153                struct commit_list *bases, *ent;
 154
 155                old_commit = (struct commit *)parse_object(old_sha1);
 156                new_commit = (struct commit *)parse_object(new_sha1);
 157                bases = get_merge_bases(old_commit, new_commit, 1);
 158                for (ent = bases; ent; ent = ent->next)
 159                        if (!hashcmp(old_sha1, ent->item->object.sha1))
 160                                break;
 161                free_commit_list(bases);
 162                if (!ent) {
 163                        error("denying non-fast forward %s"
 164                              " (you should pull first)", name);
 165                        return "non-fast forward";
 166                }
 167        }
 168        if (run_hook(update_hook, cmd, 1)) {
 169                error("hook declined to update %s", name);
 170                return "hook declined";
 171        }
 172
 173        if (is_null_sha1(new_sha1)) {
 174                if (delete_ref(name, old_sha1)) {
 175                        error("failed to delete %s", name);
 176                        return "failed to delete";
 177                }
 178                fprintf(stderr, "%s: %s -> deleted\n", name,
 179                        sha1_to_hex(old_sha1));
 180                return NULL; /* good */
 181        }
 182        else {
 183                lock = lock_any_ref_for_update(name, old_sha1);
 184                if (!lock) {
 185                        error("failed to lock %s", name);
 186                        return "failed to lock";
 187                }
 188                if (write_ref_sha1(lock, new_sha1, "push")) {
 189                        return "failed to write"; /* error() already called */
 190                }
 191                fprintf(stderr, "%s: %s -> %s\n", name,
 192                        sha1_to_hex(old_sha1), sha1_to_hex(new_sha1));
 193                return NULL; /* good */
 194        }
 195}
 196
 197static char update_post_hook[] = "hooks/post-update";
 198
 199static void run_update_post_hook(struct command *cmd)
 200{
 201        struct command *cmd_p;
 202        int argc;
 203        const char **argv;
 204
 205        for (argc = 0, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 206                if (cmd_p->error_string)
 207                        continue;
 208                argc++;
 209        }
 210        if (!argc || access(update_post_hook, X_OK) < 0)
 211                return;
 212        argv = xmalloc(sizeof(*argv) * (2 + argc));
 213        argv[0] = update_post_hook;
 214
 215        for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 216                char *p;
 217                if (cmd_p->error_string)
 218                        continue;
 219                p = xmalloc(strlen(cmd_p->ref_name) + 1);
 220                strcpy(p, cmd_p->ref_name);
 221                argv[argc] = p;
 222                argc++;
 223        }
 224        argv[argc] = NULL;
 225        run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
 226                | RUN_COMMAND_STDOUT_TO_STDERR);
 227}
 228
 229static void execute_commands(const char *unpacker_error)
 230{
 231        struct command *cmd = commands;
 232
 233        if (unpacker_error) {
 234                while (cmd) {
 235                        cmd->error_string = "n/a (unpacker error)";
 236                        cmd = cmd->next;
 237                }
 238                return;
 239        }
 240
 241        if (run_hook(pre_receive_hook, commands, 0)) {
 242                while (cmd) {
 243                        cmd->error_string = "pre-receive hook declined";
 244                        cmd = cmd->next;
 245                }
 246                return;
 247        }
 248
 249        while (cmd) {
 250                cmd->error_string = update(cmd);
 251                cmd = cmd->next;
 252        }
 253}
 254
 255static void read_head_info(void)
 256{
 257        struct command **p = &commands;
 258        for (;;) {
 259                static char line[1000];
 260                unsigned char old_sha1[20], new_sha1[20];
 261                struct command *cmd;
 262                char *refname;
 263                int len, reflen;
 264
 265                len = packet_read_line(0, line, sizeof(line));
 266                if (!len)
 267                        break;
 268                if (line[len-1] == '\n')
 269                        line[--len] = 0;
 270                if (len < 83 ||
 271                    line[40] != ' ' ||
 272                    line[81] != ' ' ||
 273                    get_sha1_hex(line, old_sha1) ||
 274                    get_sha1_hex(line + 41, new_sha1))
 275                        die("protocol error: expected old/new/ref, got '%s'",
 276                            line);
 277
 278                refname = line + 82;
 279                reflen = strlen(refname);
 280                if (reflen + 82 < len) {
 281                        if (strstr(refname + reflen + 1, "report-status"))
 282                                report_status = 1;
 283                }
 284                cmd = xmalloc(sizeof(struct command) + len - 80);
 285                hashcpy(cmd->old_sha1, old_sha1);
 286                hashcpy(cmd->new_sha1, new_sha1);
 287                memcpy(cmd->ref_name, line + 82, len - 81);
 288                cmd->error_string = NULL;
 289                cmd->next = NULL;
 290                *p = cmd;
 291                p = &cmd->next;
 292        }
 293}
 294
 295static const char *parse_pack_header(struct pack_header *hdr)
 296{
 297        switch (read_pack_header(0, hdr)) {
 298        case PH_ERROR_EOF:
 299                return "eof before pack header was fully read";
 300
 301        case PH_ERROR_PACK_SIGNATURE:
 302                return "protocol error (pack signature mismatch detected)";
 303
 304        case PH_ERROR_PROTOCOL:
 305                return "protocol error (pack version unsupported)";
 306
 307        default:
 308                return "unknown error in parse_pack_header";
 309
 310        case 0:
 311                return NULL;
 312        }
 313}
 314
 315static const char *pack_lockfile;
 316
 317static const char *unpack(void)
 318{
 319        struct pack_header hdr;
 320        const char *hdr_err;
 321        char hdr_arg[38];
 322
 323        hdr_err = parse_pack_header(&hdr);
 324        if (hdr_err)
 325                return hdr_err;
 326        snprintf(hdr_arg, sizeof(hdr_arg), "--pack_header=%u,%u",
 327                        ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
 328
 329        if (ntohl(hdr.hdr_entries) < unpack_limit) {
 330                int code;
 331                const char *unpacker[3];
 332                unpacker[0] = "unpack-objects";
 333                unpacker[1] = hdr_arg;
 334                unpacker[2] = NULL;
 335                code = run_command_v_opt(unpacker, RUN_GIT_CMD);
 336                switch (code) {
 337                case 0:
 338                        return NULL;
 339                case -ERR_RUN_COMMAND_FORK:
 340                        return "unpack fork failed";
 341                case -ERR_RUN_COMMAND_EXEC:
 342                        return "unpack execute failed";
 343                case -ERR_RUN_COMMAND_WAITPID:
 344                        return "waitpid failed";
 345                case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 346                        return "waitpid is confused";
 347                case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 348                        return "unpacker died of signal";
 349                case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 350                        return "unpacker died strangely";
 351                default:
 352                        return "unpacker exited with error code";
 353                }
 354        } else {
 355                const char *keeper[6];
 356                int fd[2], s, len, status;
 357                pid_t pid;
 358                char keep_arg[256];
 359                char packname[46];
 360
 361                s = sprintf(keep_arg, "--keep=receive-pack %i on ", getpid());
 362                if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
 363                        strcpy(keep_arg + s, "localhost");
 364
 365                keeper[0] = "index-pack";
 366                keeper[1] = "--stdin";
 367                keeper[2] = "--fix-thin";
 368                keeper[3] = hdr_arg;
 369                keeper[4] = keep_arg;
 370                keeper[5] = NULL;
 371
 372                if (pipe(fd) < 0)
 373                        return "index-pack pipe failed";
 374                pid = fork();
 375                if (pid < 0)
 376                        return "index-pack fork failed";
 377                if (!pid) {
 378                        dup2(fd[1], 1);
 379                        close(fd[1]);
 380                        close(fd[0]);
 381                        execv_git_cmd(keeper);
 382                        die("execv of index-pack failed");
 383                }
 384                close(fd[1]);
 385
 386                /*
 387                 * The first thing we expects from index-pack's output
 388                 * is "pack\t%40s\n" or "keep\t%40s\n" (46 bytes) where
 389                 * %40s is the newly created pack SHA1 name.  In the "keep"
 390                 * case, we need it to remove the corresponding .keep file
 391                 * later on.  If we don't get that then tough luck with it.
 392                 */
 393                for (len = 0;
 394                     len < 46 && (s = xread(fd[0], packname+len, 46-len)) > 0;
 395                     len += s);
 396                close(fd[0]);
 397                if (len == 46 && packname[45] == '\n' &&
 398                    memcmp(packname, "keep\t", 5) == 0) {
 399                        char path[PATH_MAX];
 400                        packname[45] = 0;
 401                        snprintf(path, sizeof(path), "%s/pack/pack-%s.keep",
 402                                 get_object_directory(), packname + 5);
 403                        pack_lockfile = xstrdup(path);
 404                }
 405
 406                /* Then wrap our index-pack process. */
 407                while (waitpid(pid, &status, 0) < 0)
 408                        if (errno != EINTR)
 409                                return "waitpid failed";
 410                if (WIFEXITED(status)) {
 411                        int code = WEXITSTATUS(status);
 412                        if (code)
 413                                return "index-pack exited with error code";
 414                        reprepare_packed_git();
 415                        return NULL;
 416                }
 417                return "index-pack abnormal exit";
 418        }
 419}
 420
 421static void report(const char *unpack_status)
 422{
 423        struct command *cmd;
 424        packet_write(1, "unpack %s\n",
 425                     unpack_status ? unpack_status : "ok");
 426        for (cmd = commands; cmd; cmd = cmd->next) {
 427                if (!cmd->error_string)
 428                        packet_write(1, "ok %s\n",
 429                                     cmd->ref_name);
 430                else
 431                        packet_write(1, "ng %s %s\n",
 432                                     cmd->ref_name, cmd->error_string);
 433        }
 434        packet_flush(1);
 435}
 436
 437static int delete_only(struct command *cmd)
 438{
 439        while (cmd) {
 440                if (!is_null_sha1(cmd->new_sha1))
 441                        return 0;
 442                cmd = cmd->next;
 443        }
 444        return 1;
 445}
 446
 447int main(int argc, char **argv)
 448{
 449        int i;
 450        char *dir = NULL;
 451
 452        argv++;
 453        for (i = 1; i < argc; i++) {
 454                char *arg = *argv++;
 455
 456                if (*arg == '-') {
 457                        /* Do flag handling here */
 458                        usage(receive_pack_usage);
 459                }
 460                if (dir)
 461                        usage(receive_pack_usage);
 462                dir = arg;
 463        }
 464        if (!dir)
 465                usage(receive_pack_usage);
 466
 467        if (!enter_repo(dir, 0))
 468                die("'%s': unable to chdir or not a git archive", dir);
 469
 470        if (is_repository_shallow())
 471                die("attempt to push into a shallow repository");
 472
 473        git_config(receive_pack_config);
 474
 475        if (0 <= transfer_unpack_limit)
 476                unpack_limit = transfer_unpack_limit;
 477        else if (0 <= receive_unpack_limit)
 478                unpack_limit = receive_unpack_limit;
 479
 480        write_head_info();
 481
 482        /* EOF */
 483        packet_flush(1);
 484
 485        read_head_info();
 486        if (commands) {
 487                const char *unpack_status = NULL;
 488
 489                if (!delete_only(commands))
 490                        unpack_status = unpack();
 491                execute_commands(unpack_status);
 492                if (pack_lockfile)
 493                        unlink(pack_lockfile);
 494                if (report_status)
 495                        report(unpack_status);
 496                run_hook(post_receive_hook, commands, 0);
 497                run_update_post_hook(commands);
 498        }
 499        return 0;
 500}