Andrew's git / gitweb.git / builtin/receive-pack.c
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builtin / receive-pack.con commit Merge branch 'jn/gitweb-dependency' (a579498)
   1#include "builtin.h"
   2#include "pack.h"
   3#include "refs.h"
   4#include "pkt-line.h"
   5#include "sideband.h"
   6#include "run-command.h"
   7#include "exec_cmd.h"
   8#include "commit.h"
   9#include "object.h"
  10#include "remote.h"
  11#include "transport.h"
  12#include "string-list.h"
  13
  14static const char receive_pack_usage[] = "git receive-pack <git-dir>";
  15
  16enum deny_action {
  17        DENY_UNCONFIGURED,
  18        DENY_IGNORE,
  19        DENY_WARN,
  20        DENY_REFUSE
  21};
  22
  23static int deny_deletes;
  24static int deny_non_fast_forwards;
  25static enum deny_action deny_current_branch = DENY_UNCONFIGURED;
  26static enum deny_action deny_delete_current = DENY_UNCONFIGURED;
  27static int receive_fsck_objects;
  28static int receive_unpack_limit = -1;
  29static int transfer_unpack_limit = -1;
  30static int unpack_limit = 100;
  31static int report_status;
  32static int use_sideband;
  33static int prefer_ofs_delta = 1;
  34static int auto_update_server_info;
  35static int auto_gc = 1;
  36static const char *head_name;
  37static int sent_capabilities;
  38
  39static enum deny_action parse_deny_action(const char *var, const char *value)
  40{
  41        if (value) {
  42                if (!strcasecmp(value, "ignore"))
  43                        return DENY_IGNORE;
  44                if (!strcasecmp(value, "warn"))
  45                        return DENY_WARN;
  46                if (!strcasecmp(value, "refuse"))
  47                        return DENY_REFUSE;
  48        }
  49        if (git_config_bool(var, value))
  50                return DENY_REFUSE;
  51        return DENY_IGNORE;
  52}
  53
  54static int receive_pack_config(const char *var, const char *value, void *cb)
  55{
  56        if (strcmp(var, "receive.denydeletes") == 0) {
  57                deny_deletes = git_config_bool(var, value);
  58                return 0;
  59        }
  60
  61        if (strcmp(var, "receive.denynonfastforwards") == 0) {
  62                deny_non_fast_forwards = git_config_bool(var, value);
  63                return 0;
  64        }
  65
  66        if (strcmp(var, "receive.unpacklimit") == 0) {
  67                receive_unpack_limit = git_config_int(var, value);
  68                return 0;
  69        }
  70
  71        if (strcmp(var, "transfer.unpacklimit") == 0) {
  72                transfer_unpack_limit = git_config_int(var, value);
  73                return 0;
  74        }
  75
  76        if (strcmp(var, "receive.fsckobjects") == 0) {
  77                receive_fsck_objects = git_config_bool(var, value);
  78                return 0;
  79        }
  80
  81        if (!strcmp(var, "receive.denycurrentbranch")) {
  82                deny_current_branch = parse_deny_action(var, value);
  83                return 0;
  84        }
  85
  86        if (strcmp(var, "receive.denydeletecurrent") == 0) {
  87                deny_delete_current = parse_deny_action(var, value);
  88                return 0;
  89        }
  90
  91        if (strcmp(var, "repack.usedeltabaseoffset") == 0) {
  92                prefer_ofs_delta = git_config_bool(var, value);
  93                return 0;
  94        }
  95
  96        if (strcmp(var, "receive.updateserverinfo") == 0) {
  97                auto_update_server_info = git_config_bool(var, value);
  98                return 0;
  99        }
 100
 101        if (strcmp(var, "receive.autogc") == 0) {
 102                auto_gc = git_config_bool(var, value);
 103                return 0;
 104        }
 105
 106        return git_default_config(var, value, cb);
 107}
 108
 109static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 110{
 111        if (sent_capabilities)
 112                packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
 113        else
 114                packet_write(1, "%s %s%c%s%s\n",
 115                             sha1_to_hex(sha1), path, 0,
 116                             " report-status delete-refs side-band-64k",
 117                             prefer_ofs_delta ? " ofs-delta" : "");
 118        sent_capabilities = 1;
 119        return 0;
 120}
 121
 122static void write_head_info(void)
 123{
 124        for_each_ref(show_ref, NULL);
 125        if (!sent_capabilities)
 126                show_ref("capabilities^{}", null_sha1, 0, NULL);
 127
 128}
 129
 130struct command {
 131        struct command *next;
 132        const char *error_string;
 133        unsigned int skip_update;
 134        unsigned char old_sha1[20];
 135        unsigned char new_sha1[20];
 136        char ref_name[FLEX_ARRAY]; /* more */
 137};
 138
 139static const char pre_receive_hook[] = "hooks/pre-receive";
 140static const char post_receive_hook[] = "hooks/post-receive";
 141
 142static void rp_error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 143static void rp_warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 144
 145static void report_message(const char *prefix, const char *err, va_list params)
 146{
 147        int sz = strlen(prefix);
 148        char msg[4096];
 149
 150        strncpy(msg, prefix, sz);
 151        sz += vsnprintf(msg + sz, sizeof(msg) - sz, err, params);
 152        if (sz > (sizeof(msg) - 1))
 153                sz = sizeof(msg) - 1;
 154        msg[sz++] = '\n';
 155
 156        if (use_sideband)
 157                send_sideband(1, 2, msg, sz, use_sideband);
 158        else
 159                xwrite(2, msg, sz);
 160}
 161
 162static void rp_warning(const char *err, ...)
 163{
 164        va_list params;
 165        va_start(params, err);
 166        report_message("warning: ", err, params);
 167        va_end(params);
 168}
 169
 170static void rp_error(const char *err, ...)
 171{
 172        va_list params;
 173        va_start(params, err);
 174        report_message("error: ", err, params);
 175        va_end(params);
 176}
 177
 178static int copy_to_sideband(int in, int out, void *arg)
 179{
 180        char data[128];
 181        while (1) {
 182                ssize_t sz = xread(in, data, sizeof(data));
 183                if (sz <= 0)
 184                        break;
 185                send_sideband(1, 2, data, sz, use_sideband);
 186        }
 187        close(in);
 188        return 0;
 189}
 190
 191static int run_receive_hook(struct command *commands, const char *hook_name)
 192{
 193        static char buf[sizeof(commands->old_sha1) * 2 + PATH_MAX + 4];
 194        struct command *cmd;
 195        struct child_process proc;
 196        struct async muxer;
 197        const char *argv[2];
 198        int have_input = 0, code;
 199
 200        for (cmd = commands; !have_input && cmd; cmd = cmd->next) {
 201                if (!cmd->error_string)
 202                        have_input = 1;
 203        }
 204
 205        if (!have_input || access(hook_name, X_OK) < 0)
 206                return 0;
 207
 208        argv[0] = hook_name;
 209        argv[1] = NULL;
 210
 211        memset(&proc, 0, sizeof(proc));
 212        proc.argv = argv;
 213        proc.in = -1;
 214        proc.stdout_to_stderr = 1;
 215
 216        if (use_sideband) {
 217                memset(&muxer, 0, sizeof(muxer));
 218                muxer.proc = copy_to_sideband;
 219                muxer.in = -1;
 220                code = start_async(&muxer);
 221                if (code)
 222                        return code;
 223                proc.err = muxer.in;
 224        }
 225
 226        code = start_command(&proc);
 227        if (code) {
 228                if (use_sideband)
 229                        finish_async(&muxer);
 230                return code;
 231        }
 232
 233        for (cmd = commands; cmd; cmd = cmd->next) {
 234                if (!cmd->error_string) {
 235                        size_t n = snprintf(buf, sizeof(buf), "%s %s %s\n",
 236                                sha1_to_hex(cmd->old_sha1),
 237                                sha1_to_hex(cmd->new_sha1),
 238                                cmd->ref_name);
 239                        if (write_in_full(proc.in, buf, n) != n)
 240                                break;
 241                }
 242        }
 243        close(proc.in);
 244        if (use_sideband)
 245                finish_async(&muxer);
 246        return finish_command(&proc);
 247}
 248
 249static int run_update_hook(struct command *cmd)
 250{
 251        static const char update_hook[] = "hooks/update";
 252        const char *argv[5];
 253        struct child_process proc;
 254        int code;
 255
 256        if (access(update_hook, X_OK) < 0)
 257                return 0;
 258
 259        argv[0] = update_hook;
 260        argv[1] = cmd->ref_name;
 261        argv[2] = sha1_to_hex(cmd->old_sha1);
 262        argv[3] = sha1_to_hex(cmd->new_sha1);
 263        argv[4] = NULL;
 264
 265        memset(&proc, 0, sizeof(proc));
 266        proc.no_stdin = 1;
 267        proc.stdout_to_stderr = 1;
 268        proc.err = use_sideband ? -1 : 0;
 269        proc.argv = argv;
 270
 271        code = start_command(&proc);
 272        if (code)
 273                return code;
 274        if (use_sideband)
 275                copy_to_sideband(proc.err, -1, NULL);
 276        return finish_command(&proc);
 277}
 278
 279static int is_ref_checked_out(const char *ref)
 280{
 281        if (is_bare_repository())
 282                return 0;
 283
 284        if (!head_name)
 285                return 0;
 286        return !strcmp(head_name, ref);
 287}
 288
 289static char *refuse_unconfigured_deny_msg[] = {
 290        "By default, updating the current branch in a non-bare repository",
 291        "is denied, because it will make the index and work tree inconsistent",
 292        "with what you pushed, and will require 'git reset --hard' to match",
 293        "the work tree to HEAD.",
 294        "",
 295        "You can set 'receive.denyCurrentBranch' configuration variable to",
 296        "'ignore' or 'warn' in the remote repository to allow pushing into",
 297        "its current branch; however, this is not recommended unless you",
 298        "arranged to update its work tree to match what you pushed in some",
 299        "other way.",
 300        "",
 301        "To squelch this message and still keep the default behaviour, set",
 302        "'receive.denyCurrentBranch' configuration variable to 'refuse'."
 303};
 304
 305static void refuse_unconfigured_deny(void)
 306{
 307        int i;
 308        for (i = 0; i < ARRAY_SIZE(refuse_unconfigured_deny_msg); i++)
 309                rp_error("%s", refuse_unconfigured_deny_msg[i]);
 310}
 311
 312static char *refuse_unconfigured_deny_delete_current_msg[] = {
 313        "By default, deleting the current branch is denied, because the next",
 314        "'git clone' won't result in any file checked out, causing confusion.",
 315        "",
 316        "You can set 'receive.denyDeleteCurrent' configuration variable to",
 317        "'warn' or 'ignore' in the remote repository to allow deleting the",
 318        "current branch, with or without a warning message.",
 319        "",
 320        "To squelch this message, you can set it to 'refuse'."
 321};
 322
 323static void refuse_unconfigured_deny_delete_current(void)
 324{
 325        int i;
 326        for (i = 0;
 327             i < ARRAY_SIZE(refuse_unconfigured_deny_delete_current_msg);
 328             i++)
 329                rp_error("%s", refuse_unconfigured_deny_delete_current_msg[i]);
 330}
 331
 332static const char *update(struct command *cmd)
 333{
 334        const char *name = cmd->ref_name;
 335        unsigned char *old_sha1 = cmd->old_sha1;
 336        unsigned char *new_sha1 = cmd->new_sha1;
 337        struct ref_lock *lock;
 338
 339        /* only refs/... are allowed */
 340        if (prefixcmp(name, "refs/") || check_ref_format(name + 5)) {
 341                rp_error("refusing to create funny ref '%s' remotely", name);
 342                return "funny refname";
 343        }
 344
 345        if (is_ref_checked_out(name)) {
 346                switch (deny_current_branch) {
 347                case DENY_IGNORE:
 348                        break;
 349                case DENY_WARN:
 350                        rp_warning("updating the current branch");
 351                        break;
 352                case DENY_REFUSE:
 353                case DENY_UNCONFIGURED:
 354                        rp_error("refusing to update checked out branch: %s", name);
 355                        if (deny_current_branch == DENY_UNCONFIGURED)
 356                                refuse_unconfigured_deny();
 357                        return "branch is currently checked out";
 358                }
 359        }
 360
 361        if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
 362                error("unpack should have generated %s, "
 363                      "but I can't find it!", sha1_to_hex(new_sha1));
 364                return "bad pack";
 365        }
 366
 367        if (!is_null_sha1(old_sha1) && is_null_sha1(new_sha1)) {
 368                if (deny_deletes && !prefixcmp(name, "refs/heads/")) {
 369                        rp_error("denying ref deletion for %s", name);
 370                        return "deletion prohibited";
 371                }
 372
 373                if (!strcmp(name, head_name)) {
 374                        switch (deny_delete_current) {
 375                        case DENY_IGNORE:
 376                                break;
 377                        case DENY_WARN:
 378                                rp_warning("deleting the current branch");
 379                                break;
 380                        case DENY_REFUSE:
 381                        case DENY_UNCONFIGURED:
 382                                if (deny_delete_current == DENY_UNCONFIGURED)
 383                                        refuse_unconfigured_deny_delete_current();
 384                                rp_error("refusing to delete the current branch: %s", name);
 385                                return "deletion of the current branch prohibited";
 386                        }
 387                }
 388        }
 389
 390        if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
 391            !is_null_sha1(old_sha1) &&
 392            !prefixcmp(name, "refs/heads/")) {
 393                struct object *old_object, *new_object;
 394                struct commit *old_commit, *new_commit;
 395                struct commit_list *bases, *ent;
 396
 397                old_object = parse_object(old_sha1);
 398                new_object = parse_object(new_sha1);
 399
 400                if (!old_object || !new_object ||
 401                    old_object->type != OBJ_COMMIT ||
 402                    new_object->type != OBJ_COMMIT) {
 403                        error("bad sha1 objects for %s", name);
 404                        return "bad ref";
 405                }
 406                old_commit = (struct commit *)old_object;
 407                new_commit = (struct commit *)new_object;
 408                bases = get_merge_bases(old_commit, new_commit, 1);
 409                for (ent = bases; ent; ent = ent->next)
 410                        if (!hashcmp(old_sha1, ent->item->object.sha1))
 411                                break;
 412                free_commit_list(bases);
 413                if (!ent) {
 414                        rp_error("denying non-fast-forward %s"
 415                                 " (you should pull first)", name);
 416                        return "non-fast-forward";
 417                }
 418        }
 419        if (run_update_hook(cmd)) {
 420                rp_error("hook declined to update %s", name);
 421                return "hook declined";
 422        }
 423
 424        if (is_null_sha1(new_sha1)) {
 425                if (!parse_object(old_sha1)) {
 426                        rp_warning("Allowing deletion of corrupt ref.");
 427                        old_sha1 = NULL;
 428                }
 429                if (delete_ref(name, old_sha1, 0)) {
 430                        rp_error("failed to delete %s", name);
 431                        return "failed to delete";
 432                }
 433                return NULL; /* good */
 434        }
 435        else {
 436                lock = lock_any_ref_for_update(name, old_sha1, 0);
 437                if (!lock) {
 438                        rp_error("failed to lock %s", name);
 439                        return "failed to lock";
 440                }
 441                if (write_ref_sha1(lock, new_sha1, "push")) {
 442                        return "failed to write"; /* error() already called */
 443                }
 444                return NULL; /* good */
 445        }
 446}
 447
 448static char update_post_hook[] = "hooks/post-update";
 449
 450static void run_update_post_hook(struct command *commands)
 451{
 452        struct command *cmd;
 453        int argc;
 454        const char **argv;
 455        struct child_process proc;
 456
 457        for (argc = 0, cmd = commands; cmd; cmd = cmd->next) {
 458                if (cmd->error_string)
 459                        continue;
 460                argc++;
 461        }
 462        if (!argc || access(update_post_hook, X_OK) < 0)
 463                return;
 464        argv = xmalloc(sizeof(*argv) * (2 + argc));
 465        argv[0] = update_post_hook;
 466
 467        for (argc = 1, cmd = commands; cmd; cmd = cmd->next) {
 468                char *p;
 469                if (cmd->error_string)
 470                        continue;
 471                p = xmalloc(strlen(cmd->ref_name) + 1);
 472                strcpy(p, cmd->ref_name);
 473                argv[argc] = p;
 474                argc++;
 475        }
 476        argv[argc] = NULL;
 477
 478        memset(&proc, 0, sizeof(proc));
 479        proc.no_stdin = 1;
 480        proc.stdout_to_stderr = 1;
 481        proc.err = use_sideband ? -1 : 0;
 482        proc.argv = argv;
 483
 484        if (!start_command(&proc)) {
 485                if (use_sideband)
 486                        copy_to_sideband(proc.err, -1, NULL);
 487                finish_command(&proc);
 488        }
 489}
 490
 491static void check_aliased_update(struct command *cmd, struct string_list *list)
 492{
 493        struct string_list_item *item;
 494        struct command *dst_cmd;
 495        unsigned char sha1[20];
 496        char cmd_oldh[41], cmd_newh[41], dst_oldh[41], dst_newh[41];
 497        int flag;
 498
 499        const char *dst_name = resolve_ref(cmd->ref_name, sha1, 0, &flag);
 500
 501        if (!(flag & REF_ISSYMREF))
 502                return;
 503
 504        if ((item = string_list_lookup(list, dst_name)) == NULL)
 505                return;
 506
 507        cmd->skip_update = 1;
 508
 509        dst_cmd = (struct command *) item->util;
 510
 511        if (!hashcmp(cmd->old_sha1, dst_cmd->old_sha1) &&
 512            !hashcmp(cmd->new_sha1, dst_cmd->new_sha1))
 513                return;
 514
 515        dst_cmd->skip_update = 1;
 516
 517        strcpy(cmd_oldh, find_unique_abbrev(cmd->old_sha1, DEFAULT_ABBREV));
 518        strcpy(cmd_newh, find_unique_abbrev(cmd->new_sha1, DEFAULT_ABBREV));
 519        strcpy(dst_oldh, find_unique_abbrev(dst_cmd->old_sha1, DEFAULT_ABBREV));
 520        strcpy(dst_newh, find_unique_abbrev(dst_cmd->new_sha1, DEFAULT_ABBREV));
 521        rp_error("refusing inconsistent update between symref '%s' (%s..%s) and"
 522                 " its target '%s' (%s..%s)",
 523                 cmd->ref_name, cmd_oldh, cmd_newh,
 524                 dst_cmd->ref_name, dst_oldh, dst_newh);
 525
 526        cmd->error_string = dst_cmd->error_string =
 527                "inconsistent aliased update";
 528}
 529
 530static void check_aliased_updates(struct command *commands)
 531{
 532        struct command *cmd;
 533        struct string_list ref_list = STRING_LIST_INIT_NODUP;
 534
 535        for (cmd = commands; cmd; cmd = cmd->next) {
 536                struct string_list_item *item =
 537                        string_list_append(&ref_list, cmd->ref_name);
 538                item->util = (void *)cmd;
 539        }
 540        sort_string_list(&ref_list);
 541
 542        for (cmd = commands; cmd; cmd = cmd->next)
 543                check_aliased_update(cmd, &ref_list);
 544
 545        string_list_clear(&ref_list, 0);
 546}
 547
 548static void execute_commands(struct command *commands, const char *unpacker_error)
 549{
 550        struct command *cmd;
 551        unsigned char sha1[20];
 552
 553        if (unpacker_error) {
 554                for (cmd = commands; cmd; cmd = cmd->next)
 555                        cmd->error_string = "n/a (unpacker error)";
 556                return;
 557        }
 558
 559        if (run_receive_hook(commands, pre_receive_hook)) {
 560                for (cmd = commands; cmd; cmd = cmd->next)
 561                        cmd->error_string = "pre-receive hook declined";
 562                return;
 563        }
 564
 565        check_aliased_updates(commands);
 566
 567        head_name = resolve_ref("HEAD", sha1, 0, NULL);
 568
 569        for (cmd = commands; cmd; cmd = cmd->next)
 570                if (!cmd->skip_update)
 571                        cmd->error_string = update(cmd);
 572}
 573
 574static struct command *read_head_info(void)
 575{
 576        struct command *commands = NULL;
 577        struct command **p = &commands;
 578        for (;;) {
 579                static char line[1000];
 580                unsigned char old_sha1[20], new_sha1[20];
 581                struct command *cmd;
 582                char *refname;
 583                int len, reflen;
 584
 585                len = packet_read_line(0, line, sizeof(line));
 586                if (!len)
 587                        break;
 588                if (line[len-1] == '\n')
 589                        line[--len] = 0;
 590                if (len < 83 ||
 591                    line[40] != ' ' ||
 592                    line[81] != ' ' ||
 593                    get_sha1_hex(line, old_sha1) ||
 594                    get_sha1_hex(line + 41, new_sha1))
 595                        die("protocol error: expected old/new/ref, got '%s'",
 596                            line);
 597
 598                refname = line + 82;
 599                reflen = strlen(refname);
 600                if (reflen + 82 < len) {
 601                        if (strstr(refname + reflen + 1, "report-status"))
 602                                report_status = 1;
 603                        if (strstr(refname + reflen + 1, "side-band-64k"))
 604                                use_sideband = LARGE_PACKET_MAX;
 605                }
 606                cmd = xcalloc(1, sizeof(struct command) + len - 80);
 607                hashcpy(cmd->old_sha1, old_sha1);
 608                hashcpy(cmd->new_sha1, new_sha1);
 609                memcpy(cmd->ref_name, line + 82, len - 81);
 610                *p = cmd;
 611                p = &cmd->next;
 612        }
 613        return commands;
 614}
 615
 616static const char *parse_pack_header(struct pack_header *hdr)
 617{
 618        switch (read_pack_header(0, hdr)) {
 619        case PH_ERROR_EOF:
 620                return "eof before pack header was fully read";
 621
 622        case PH_ERROR_PACK_SIGNATURE:
 623                return "protocol error (pack signature mismatch detected)";
 624
 625        case PH_ERROR_PROTOCOL:
 626                return "protocol error (pack version unsupported)";
 627
 628        default:
 629                return "unknown error in parse_pack_header";
 630
 631        case 0:
 632                return NULL;
 633        }
 634}
 635
 636static const char *pack_lockfile;
 637
 638static const char *unpack(void)
 639{
 640        struct pack_header hdr;
 641        const char *hdr_err;
 642        char hdr_arg[38];
 643
 644        hdr_err = parse_pack_header(&hdr);
 645        if (hdr_err)
 646                return hdr_err;
 647        snprintf(hdr_arg, sizeof(hdr_arg),
 648                        "--pack_header=%"PRIu32",%"PRIu32,
 649                        ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
 650
 651        if (ntohl(hdr.hdr_entries) < unpack_limit) {
 652                int code, i = 0;
 653                const char *unpacker[4];
 654                unpacker[i++] = "unpack-objects";
 655                if (receive_fsck_objects)
 656                        unpacker[i++] = "--strict";
 657                unpacker[i++] = hdr_arg;
 658                unpacker[i++] = NULL;
 659                code = run_command_v_opt(unpacker, RUN_GIT_CMD);
 660                if (!code)
 661                        return NULL;
 662                return "unpack-objects abnormal exit";
 663        } else {
 664                const char *keeper[7];
 665                int s, status, i = 0;
 666                char keep_arg[256];
 667                struct child_process ip;
 668
 669                s = sprintf(keep_arg, "--keep=receive-pack %"PRIuMAX" on ", (uintmax_t) getpid());
 670                if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
 671                        strcpy(keep_arg + s, "localhost");
 672
 673                keeper[i++] = "index-pack";
 674                keeper[i++] = "--stdin";
 675                if (receive_fsck_objects)
 676                        keeper[i++] = "--strict";
 677                keeper[i++] = "--fix-thin";
 678                keeper[i++] = hdr_arg;
 679                keeper[i++] = keep_arg;
 680                keeper[i++] = NULL;
 681                memset(&ip, 0, sizeof(ip));
 682                ip.argv = keeper;
 683                ip.out = -1;
 684                ip.git_cmd = 1;
 685                status = start_command(&ip);
 686                if (status) {
 687                        return "index-pack fork failed";
 688                }
 689                pack_lockfile = index_pack_lockfile(ip.out);
 690                close(ip.out);
 691                status = finish_command(&ip);
 692                if (!status) {
 693                        reprepare_packed_git();
 694                        return NULL;
 695                }
 696                return "index-pack abnormal exit";
 697        }
 698}
 699
 700static void report(struct command *commands, const char *unpack_status)
 701{
 702        struct command *cmd;
 703        struct strbuf buf = STRBUF_INIT;
 704
 705        packet_buf_write(&buf, "unpack %s\n",
 706                         unpack_status ? unpack_status : "ok");
 707        for (cmd = commands; cmd; cmd = cmd->next) {
 708                if (!cmd->error_string)
 709                        packet_buf_write(&buf, "ok %s\n",
 710                                         cmd->ref_name);
 711                else
 712                        packet_buf_write(&buf, "ng %s %s\n",
 713                                         cmd->ref_name, cmd->error_string);
 714        }
 715        packet_buf_flush(&buf);
 716
 717        if (use_sideband)
 718                send_sideband(1, 1, buf.buf, buf.len, use_sideband);
 719        else
 720                safe_write(1, buf.buf, buf.len);
 721        strbuf_release(&buf);
 722}
 723
 724static int delete_only(struct command *commands)
 725{
 726        struct command *cmd;
 727        for (cmd = commands; cmd; cmd = cmd->next) {
 728                if (!is_null_sha1(cmd->new_sha1))
 729                        return 0;
 730        }
 731        return 1;
 732}
 733
 734static void add_one_alternate_ref(const struct ref *ref, void *unused)
 735{
 736        add_extra_ref(".have", ref->old_sha1, 0);
 737}
 738
 739static void add_alternate_refs(void)
 740{
 741        foreach_alt_odb(refs_from_alternate_cb, add_one_alternate_ref);
 742}
 743
 744int cmd_receive_pack(int argc, const char **argv, const char *prefix)
 745{
 746        int advertise_refs = 0;
 747        int stateless_rpc = 0;
 748        int i;
 749        char *dir = NULL;
 750        struct command *commands;
 751
 752        packet_trace_identity("receive-pack");
 753
 754        argv++;
 755        for (i = 1; i < argc; i++) {
 756                const char *arg = *argv++;
 757
 758                if (*arg == '-') {
 759                        if (!strcmp(arg, "--advertise-refs")) {
 760                                advertise_refs = 1;
 761                                continue;
 762                        }
 763                        if (!strcmp(arg, "--stateless-rpc")) {
 764                                stateless_rpc = 1;
 765                                continue;
 766                        }
 767
 768                        usage(receive_pack_usage);
 769                }
 770                if (dir)
 771                        usage(receive_pack_usage);
 772                dir = xstrdup(arg);
 773        }
 774        if (!dir)
 775                usage(receive_pack_usage);
 776
 777        setup_path();
 778
 779        if (!enter_repo(dir, 0))
 780                die("'%s' does not appear to be a git repository", dir);
 781
 782        if (is_repository_shallow())
 783                die("attempt to push into a shallow repository");
 784
 785        git_config(receive_pack_config, NULL);
 786
 787        if (0 <= transfer_unpack_limit)
 788                unpack_limit = transfer_unpack_limit;
 789        else if (0 <= receive_unpack_limit)
 790                unpack_limit = receive_unpack_limit;
 791
 792        if (advertise_refs || !stateless_rpc) {
 793                add_alternate_refs();
 794                write_head_info();
 795                clear_extra_refs();
 796
 797                /* EOF */
 798                packet_flush(1);
 799        }
 800        if (advertise_refs)
 801                return 0;
 802
 803        if ((commands = read_head_info()) != NULL) {
 804                const char *unpack_status = NULL;
 805
 806                if (!delete_only(commands))
 807                        unpack_status = unpack();
 808                execute_commands(commands, unpack_status);
 809                if (pack_lockfile)
 810                        unlink_or_warn(pack_lockfile);
 811                if (report_status)
 812                        report(commands, unpack_status);
 813                run_receive_hook(commands, post_receive_hook);
 814                run_update_post_hook(commands);
 815                if (auto_gc) {
 816                        const char *argv_gc_auto[] = {
 817                                "gc", "--auto", "--quiet", NULL,
 818                        };
 819                        run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
 820                }
 821                if (auto_update_server_info)
 822                        update_server_info(0);
 823        }
 824        if (use_sideband)
 825                packet_flush(1);
 826        return 0;
 827}