builtin/receive-pack.c

   1 #include "builtin.h"
   2 #include "repository.h"
   3 #include "config.h"
   4 #include "lockfile.h"
   5 #include "pack.h"
   6 #include "refs.h"
   7 #include "pkt-line.h"
   8 #include "sideband.h"
   9 #include "run-command.h"
  10 #include "exec-cmd.h"
  11 #include "commit.h"
  12 #include "object.h"
  13 #include "remote.h"
  14 #include "connect.h"
  15 #include "transport.h"
  16 #include "string-list.h"
  17 #include "sha1-array.h"
  18 #include "connected.h"
  19 #include "argv-array.h"
  20 #include "version.h"
  21 #include "tag.h"
  22 #include "gpg-interface.h"
  23 #include "sigchain.h"
  24 #include "fsck.h"
  25 #include "tmp-objdir.h"
  26 #include "oidset.h"
  27 #include "packfile.h"
  28 #include "object-store.h"
  29 #include "protocol.h"
  30 #include "commit-reach.h"
  31
  32 static const char * const receive_pack_usage[] = {
  33         N_("git receive-pack <git-dir>"),
  34         NULL
  35 };
  36
  37 enum deny_action {
  38         DENY_UNCONFIGURED,
  39         DENY_IGNORE,
  40         DENY_WARN,
  41         DENY_REFUSE,
  42         DENY_UPDATE_INSTEAD
  43 };
  44
  45 static int deny_deletes;
  46 static int deny_non_fast_forwards;
  47 static enum deny_action deny_current_branch = DENY_UNCONFIGURED;
  48 static enum deny_action deny_delete_current = DENY_UNCONFIGURED;
  49 static int receive_fsck_objects = -1;
  50 static int transfer_fsck_objects = -1;
  51 static struct strbuf fsck_msg_types = STRBUF_INIT;
  52 static int receive_unpack_limit = -1;
  53 static int transfer_unpack_limit = -1;
  54 static int advertise_atomic_push = 1;
  55 static int advertise_push_options;
  56 static int unpack_limit = 100;
  57 static off_t max_input_size;
  58 static int report_status;
  59 static int use_sideband;
  60 static int use_atomic;
  61 static int use_push_options;
  62 static int quiet;
  63 static int prefer_ofs_delta = 1;
  64 static int auto_update_server_info;
  65 static int auto_gc = 1;
  66 static int reject_thin;
  67 static int stateless_rpc;
  68 static const char *service_dir;
  69 static const char *head_name;
  70 static void *head_name_to_free;
  71 static int sent_capabilities;
  72 static int shallow_update;
  73 static const char *alt_shallow_file;
  74 static struct strbuf push_cert = STRBUF_INIT;
  75 static struct object_id push_cert_oid;
  76 static struct signature_check sigcheck;
  77 static const char *push_cert_nonce;
  78 static const char *cert_nonce_seed;
  79
  80 static const char *NONCE_UNSOLICITED = "UNSOLICITED";
  81 static const char *NONCE_BAD = "BAD";
  82 static const char *NONCE_MISSING = "MISSING";
  83 static const char *NONCE_OK = "OK";
  84 static const char *NONCE_SLOP = "SLOP";
  85 static const char *nonce_status;
  86 static long nonce_stamp_slop;
  87 static timestamp_t nonce_stamp_slop_limit;
  88 static struct ref_transaction *transaction;
  89
  90 static enum {
  91         KEEPALIVE_NEVER = 0,
  92         KEEPALIVE_AFTER_NUL,
  93         KEEPALIVE_ALWAYS
  94 } use_keepalive;
  95 static int keepalive_in_sec = 5;
  96
  97 static struct tmp_objdir *tmp_objdir;
  98
  99 static enum deny_action parse_deny_action(const char *var, const char *value)
 100 {
 101         if (value) {
 102                 if (!strcasecmp(value, "ignore"))
 103                         return DENY_IGNORE;
 104                 if (!strcasecmp(value, "warn"))
 105                         return DENY_WARN;
 106                 if (!strcasecmp(value, "refuse"))
 107                         return DENY_REFUSE;
 108                 if (!strcasecmp(value, "updateinstead"))
 109                         return DENY_UPDATE_INSTEAD;
 110         }
 111         if (git_config_bool(var, value))
 112                 return DENY_REFUSE;
 113         return DENY_IGNORE;
 114 }
 115
 116 static int receive_pack_config(const char *var, const char *value, void *cb)
 117 {
 118         int status = parse_hide_refs_config(var, value, "receive");
 119
 120         if (status)
 121                 return status;
 122
 123         if (strcmp(var, "receive.denydeletes") == 0) {
 124                 deny_deletes = git_config_bool(var, value);
 125                 return 0;
 126         }
 127
 128         if (strcmp(var, "receive.denynonfastforwards") == 0) {
 129                 deny_non_fast_forwards = git_config_bool(var, value);
 130                 return 0;
 131         }
 132
 133         if (strcmp(var, "receive.unpacklimit") == 0) {
 134                 receive_unpack_limit = git_config_int(var, value);
 135                 return 0;
 136         }
 137
 138         if (strcmp(var, "transfer.unpacklimit") == 0) {
 139                 transfer_unpack_limit = git_config_int(var, value);
 140                 return 0;
 141         }
 142
 143         if (strcmp(var, "receive.fsck.skiplist") == 0) {
 144                 const char *path;
 145
 146                 if (git_config_pathname(&path, var, value))
 147                         return 1;
 148                 strbuf_addf(&fsck_msg_types, "%cskiplist=%s",
 149                         fsck_msg_types.len ? ',' : '=', path);
 150                 free((char *)path);
 151                 return 0;
 152         }
 153
 154         if (skip_prefix(var, "receive.fsck.", &var)) {
 155                 if (is_valid_msg_type(var, value))
 156                         strbuf_addf(&fsck_msg_types, "%c%s=%s",
 157                                 fsck_msg_types.len ? ',' : '=', var, value);
 158                 else
 159                         warning("Skipping unknown msg id '%s'", var);
 160                 return 0;
 161         }
 162
 163         if (strcmp(var, "receive.fsckobjects") == 0) {
 164                 receive_fsck_objects = git_config_bool(var, value);
 165                 return 0;
 166         }
 167
 168         if (strcmp(var, "transfer.fsckobjects") == 0) {
 169                 transfer_fsck_objects = git_config_bool(var, value);
 170                 return 0;
 171         }
 172
 173         if (!strcmp(var, "receive.denycurrentbranch")) {
 174                 deny_current_branch = parse_deny_action(var, value);
 175                 return 0;
 176         }
 177
 178         if (strcmp(var, "receive.denydeletecurrent") == 0) {
 179                 deny_delete_current = parse_deny_action(var, value);
 180                 return 0;
 181         }
 182
 183         if (strcmp(var, "repack.usedeltabaseoffset") == 0) {
 184                 prefer_ofs_delta = git_config_bool(var, value);
 185                 return 0;
 186         }
 187
 188         if (strcmp(var, "receive.updateserverinfo") == 0) {
 189                 auto_update_server_info = git_config_bool(var, value);
 190                 return 0;
 191         }
 192
 193         if (strcmp(var, "receive.autogc") == 0) {
 194                 auto_gc = git_config_bool(var, value);
 195                 return 0;
 196         }
 197
 198         if (strcmp(var, "receive.shallowupdate") == 0) {
 199                 shallow_update = git_config_bool(var, value);
 200                 return 0;
 201         }
 202
 203         if (strcmp(var, "receive.certnonceseed") == 0)
 204                 return git_config_string(&cert_nonce_seed, var, value);
 205
 206         if (strcmp(var, "receive.certnonceslop") == 0) {
 207                 nonce_stamp_slop_limit = git_config_ulong(var, value);
 208                 return 0;
 209         }
 210
 211         if (strcmp(var, "receive.advertiseatomic") == 0) {
 212                 advertise_atomic_push = git_config_bool(var, value);
 213                 return 0;
 214         }
 215
 216         if (strcmp(var, "receive.advertisepushoptions") == 0) {
 217                 advertise_push_options = git_config_bool(var, value);
 218                 return 0;
 219         }
 220
 221         if (strcmp(var, "receive.keepalive") == 0) {
 222                 keepalive_in_sec = git_config_int(var, value);
 223                 return 0;
 224         }
 225
 226         if (strcmp(var, "receive.maxinputsize") == 0) {
 227                 max_input_size = git_config_int64(var, value);
 228                 return 0;
 229         }
 230
 231         return git_default_config(var, value, cb);
 232 }
 233
 234 static void show_ref(const char *path, const struct object_id *oid)
 235 {
 236         if (sent_capabilities) {
 237                 packet_write_fmt(1, "%s %s\n", oid_to_hex(oid), path);
 238         } else {
 239                 struct strbuf cap = STRBUF_INIT;
 240
 241                 strbuf_addstr(&cap,
 242                               "report-status delete-refs side-band-64k quiet");
 243                 if (advertise_atomic_push)
 244                         strbuf_addstr(&cap, " atomic");
 245                 if (prefer_ofs_delta)
 246                         strbuf_addstr(&cap, " ofs-delta");
 247                 if (push_cert_nonce)
 248                         strbuf_addf(&cap, " push-cert=%s", push_cert_nonce);
 249                 if (advertise_push_options)
 250                         strbuf_addstr(&cap, " push-options");
 251                 strbuf_addf(&cap, " agent=%s", git_user_agent_sanitized());
 252                 packet_write_fmt(1, "%s %s%c%s\n",
 253                              oid_to_hex(oid), path, 0, cap.buf);
 254                 strbuf_release(&cap);
 255                 sent_capabilities = 1;
 256         }
 257 }
 258
 259 static int show_ref_cb(const char *path_full, const struct object_id *oid,
 260                        int flag, void *data)
 261 {
 262         struct oidset *seen = data;
 263         const char *path = strip_namespace(path_full);
 264
 265         if (ref_is_hidden(path, path_full))
 266                 return 0;
 267
 268         /*
 269          * Advertise refs outside our current namespace as ".have"
 270          * refs, so that the client can use them to minimize data
 271          * transfer but will otherwise ignore them.
 272          */
 273         if (!path) {
 274                 if (oidset_insert(seen, oid))
 275                         return 0;
 276                 path = ".have";
 277         } else {
 278                 oidset_insert(seen, oid);
 279         }
 280         show_ref(path, oid);
 281         return 0;
 282 }
 283
 284 static void show_one_alternate_ref(const struct object_id *oid,
 285                                    void *data)
 286 {
 287         struct oidset *seen = data;
 288
 289         if (oidset_insert(seen, oid))
 290                 return;
 291
 292         show_ref(".have", oid);
 293 }
 294
 295 static void write_head_info(void)
 296 {
 297         static struct oidset seen = OIDSET_INIT;
 298
 299         for_each_ref(show_ref_cb, &seen);
 300         for_each_alternate_ref(show_one_alternate_ref, &seen);
 301         oidset_clear(&seen);
 302         if (!sent_capabilities)
 303                 show_ref("capabilities^{}", &null_oid);
 304
 305         advertise_shallow_grafts(1);
 306
 307         /* EOF */
 308         packet_flush(1);
 309 }
 310
 311 struct command {
 312         struct command *next;
 313         const char *error_string;
 314         unsigned int skip_update:1,
 315                      did_not_exist:1;
 316         int index;
 317         struct object_id old_oid;
 318         struct object_id new_oid;
 319         char ref_name[FLEX_ARRAY]; /* more */
 320 };
 321
 322 static void rp_error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 323 static void rp_warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 324
 325 static void report_message(const char *prefix, const char *err, va_list params)
 326 {
 327         int sz;
 328         char msg[4096];
 329
 330         sz = xsnprintf(msg, sizeof(msg), "%s", prefix);
 331         sz += vsnprintf(msg + sz, sizeof(msg) - sz, err, params);
 332         if (sz > (sizeof(msg) - 1))
 333                 sz = sizeof(msg) - 1;
 334         msg[sz++] = '\n';
 335
 336         if (use_sideband)
 337                 send_sideband(1, 2, msg, sz, use_sideband);
 338         else
 339                 xwrite(2, msg, sz);
 340 }
 341
 342 static void rp_warning(const char *err, ...)
 343 {
 344         va_list params;
 345         va_start(params, err);
 346         report_message("warning: ", err, params);
 347         va_end(params);
 348 }
 349
 350 static void rp_error(const char *err, ...)
 351 {
 352         va_list params;
 353         va_start(params, err);
 354         report_message("error: ", err, params);
 355         va_end(params);
 356 }
 357
 358 static int copy_to_sideband(int in, int out, void *arg)
 359 {
 360         char data[128];
 361         int keepalive_active = 0;
 362
 363         if (keepalive_in_sec <= 0)
 364                 use_keepalive = KEEPALIVE_NEVER;
 365         if (use_keepalive == KEEPALIVE_ALWAYS)
 366                 keepalive_active = 1;
 367
 368         while (1) {
 369                 ssize_t sz;
 370
 371                 if (keepalive_active) {
 372                         struct pollfd pfd;
 373                         int ret;
 374
 375                         pfd.fd = in;
 376                         pfd.events = POLLIN;
 377                         ret = poll(&pfd, 1, 1000 * keepalive_in_sec);
 378
 379                         if (ret < 0) {
 380                                 if (errno == EINTR)
 381                                         continue;
 382                                 else
 383                                         break;
 384                         } else if (ret == 0) {
 385                                 /* no data; send a keepalive packet */
 386                                 static const char buf[] = "0005\1";
 387                                 write_or_die(1, buf, sizeof(buf) - 1);
 388                                 continue;
 389                         } /* else there is actual data to read */
 390                 }
 391
 392                 sz = xread(in, data, sizeof(data));
 393                 if (sz <= 0)
 394                         break;
 395
 396                 if (use_keepalive == KEEPALIVE_AFTER_NUL && !keepalive_active) {
 397                         const char *p = memchr(data, '\0', sz);
 398                         if (p) {
 399                                 /*
 400                                  * The NUL tells us to start sending keepalives. Make
 401                                  * sure we send any other data we read along
 402                                  * with it.
 403                                  */
 404                                 keepalive_active = 1;
 405                                 send_sideband(1, 2, data, p - data, use_sideband);
 406                                 send_sideband(1, 2, p + 1, sz - (p - data + 1), use_sideband);
 407                                 continue;
 408                         }
 409                 }
 410
 411                 /*
 412                  * Either we're not looking for a NUL signal, or we didn't see
 413                  * it yet; just pass along the data.
 414                  */
 415                 send_sideband(1, 2, data, sz, use_sideband);
 416         }
 417         close(in);
 418         return 0;
 419 }
 420
 421 #define HMAC_BLOCK_SIZE 64
 422
 423 static void hmac_sha1(unsigned char *out,
 424                       const char *key_in, size_t key_len,
 425                       const char *text, size_t text_len)
 426 {
 427         unsigned char key[HMAC_BLOCK_SIZE];
 428         unsigned char k_ipad[HMAC_BLOCK_SIZE];
 429         unsigned char k_opad[HMAC_BLOCK_SIZE];
 430         int i;
 431         git_SHA_CTX ctx;
 432
 433         /* RFC 2104 2. (1) */
 434         memset(key, '\0', HMAC_BLOCK_SIZE);
 435         if (HMAC_BLOCK_SIZE < key_len) {
 436                 git_SHA1_Init(&ctx);
 437                 git_SHA1_Update(&ctx, key_in, key_len);
 438                 git_SHA1_Final(key, &ctx);
 439         } else {
 440                 memcpy(key, key_in, key_len);
 441         }
 442
 443         /* RFC 2104 2. (2) & (5) */
 444         for (i = 0; i < sizeof(key); i++) {
 445                 k_ipad[i] = key[i] ^ 0x36;
 446                 k_opad[i] = key[i] ^ 0x5c;
 447         }
 448
 449         /* RFC 2104 2. (3) & (4) */
 450         git_SHA1_Init(&ctx);
 451         git_SHA1_Update(&ctx, k_ipad, sizeof(k_ipad));
 452         git_SHA1_Update(&ctx, text, text_len);
 453         git_SHA1_Final(out, &ctx);
 454
 455         /* RFC 2104 2. (6) & (7) */
 456         git_SHA1_Init(&ctx);
 457         git_SHA1_Update(&ctx, k_opad, sizeof(k_opad));
 458         git_SHA1_Update(&ctx, out, GIT_SHA1_RAWSZ);
 459         git_SHA1_Final(out, &ctx);
 460 }
 461
 462 static char *prepare_push_cert_nonce(const char *path, timestamp_t stamp)
 463 {
 464         struct strbuf buf = STRBUF_INIT;
 465         unsigned char sha1[GIT_SHA1_RAWSZ];
 466
 467         strbuf_addf(&buf, "%s:%"PRItime, path, stamp);
 468         hmac_sha1(sha1, buf.buf, buf.len, cert_nonce_seed, strlen(cert_nonce_seed));
 469         strbuf_release(&buf);
 470
 471         /* RFC 2104 5. HMAC-SHA1-80 */
 472         strbuf_addf(&buf, "%"PRItime"-%.*s", stamp, GIT_SHA1_HEXSZ, sha1_to_hex(sha1));
 473         return strbuf_detach(&buf, NULL);
 474 }
 475
 476 /*
 477  * NEEDSWORK: reuse find_commit_header() from jk/commit-author-parsing
 478  * after dropping "_commit" from its name and possibly moving it out
 479  * of commit.c
 480  */
 481 static char *find_header(const char *msg, size_t len, const char *key,
 482                          const char **next_line)
 483 {
 484         int key_len = strlen(key);
 485         const char *line = msg;
 486
 487         while (line && line < msg + len) {
 488                 const char *eol = strchrnul(line, '\n');
 489
 490                 if ((msg + len <= eol) || line == eol)
 491                         return NULL;
 492                 if (line + key_len < eol &&
 493                     !memcmp(line, key, key_len) && line[key_len] == ' ') {
 494                         int offset = key_len + 1;
 495                         if (next_line)
 496                                 *next_line = *eol ? eol + 1 : eol;
 497                         return xmemdupz(line + offset, (eol - line) - offset);
 498                 }
 499                 line = *eol ? eol + 1 : NULL;
 500         }
 501         return NULL;
 502 }
 503
 504 static const char *check_nonce(const char *buf, size_t len)
 505 {
 506         char *nonce = find_header(buf, len, "nonce", NULL);
 507         timestamp_t stamp, ostamp;
 508         char *bohmac, *expect = NULL;
 509         const char *retval = NONCE_BAD;
 510
 511         if (!nonce) {
 512                 retval = NONCE_MISSING;
 513                 goto leave;
 514         } else if (!push_cert_nonce) {
 515                 retval = NONCE_UNSOLICITED;
 516                 goto leave;
 517         } else if (!strcmp(push_cert_nonce, nonce)) {
 518                 retval = NONCE_OK;
 519                 goto leave;
 520         }
 521
 522         if (!stateless_rpc) {
 523                 /* returned nonce MUST match what we gave out earlier */
 524                 retval = NONCE_BAD;
 525                 goto leave;
 526         }
 527
 528         /*
 529          * In stateless mode, we may be receiving a nonce issued by
 530          * another instance of the server that serving the same
 531          * repository, and the timestamps may not match, but the
 532          * nonce-seed and dir should match, so we can recompute and
 533          * report the time slop.
 534          *
 535          * In addition, when a nonce issued by another instance has
 536          * timestamp within receive.certnonceslop seconds, we pretend
 537          * as if we issued that nonce when reporting to the hook.
 538          */
 539
 540         /* nonce is concat(<seconds-since-epoch>, "-", <hmac>) */
 541         if (*nonce <= '0' || '9' < *nonce) {
 542                 retval = NONCE_BAD;
 543                 goto leave;
 544         }
 545         stamp = parse_timestamp(nonce, &bohmac, 10);
 546         if (bohmac == nonce || bohmac[0] != '-') {
 547                 retval = NONCE_BAD;
 548                 goto leave;
 549         }
 550
 551         expect = prepare_push_cert_nonce(service_dir, stamp);
 552         if (strcmp(expect, nonce)) {
 553                 /* Not what we would have signed earlier */
 554                 retval = NONCE_BAD;
 555                 goto leave;
 556         }
 557
 558         /*
 559          * By how many seconds is this nonce stale?  Negative value
 560          * would mean it was issued by another server with its clock
 561          * skewed in the future.
 562          */
 563         ostamp = parse_timestamp(push_cert_nonce, NULL, 10);
 564         nonce_stamp_slop = (long)ostamp - (long)stamp;
 565
 566         if (nonce_stamp_slop_limit &&
 567             labs(nonce_stamp_slop) <= nonce_stamp_slop_limit) {
 568                 /*
 569                  * Pretend as if the received nonce (which passes the
 570                  * HMAC check, so it is not a forged by third-party)
 571                  * is what we issued.
 572                  */
 573                 free((void *)push_cert_nonce);
 574                 push_cert_nonce = xstrdup(nonce);
 575                 retval = NONCE_OK;
 576         } else {
 577                 retval = NONCE_SLOP;
 578         }
 579
 580 leave:
 581         free(nonce);
 582         free(expect);
 583         return retval;
 584 }
 585
 586 /*
 587  * Return 1 if there is no push_cert or if the push options in push_cert are
 588  * the same as those in the argument; 0 otherwise.
 589  */
 590 static int check_cert_push_options(const struct string_list *push_options)
 591 {
 592         const char *buf = push_cert.buf;
 593         int len = push_cert.len;
 594
 595         char *option;
 596         const char *next_line;
 597         int options_seen = 0;
 598
 599         int retval = 1;
 600
 601         if (!len)
 602                 return 1;
 603
 604         while ((option = find_header(buf, len, "push-option", &next_line))) {
 605                 len -= (next_line - buf);
 606                 buf = next_line;
 607                 options_seen++;
 608                 if (options_seen > push_options->nr
 609                     || strcmp(option,
 610                               push_options->items[options_seen - 1].string)) {
 611                         retval = 0;
 612                         goto leave;
 613                 }
 614                 free(option);
 615         }
 616
 617         if (options_seen != push_options->nr)
 618                 retval = 0;
 619
 620 leave:
 621         free(option);
 622         return retval;
 623 }
 624
 625 static void prepare_push_cert_sha1(struct child_process *proc)
 626 {
 627         static int already_done;
 628
 629         if (!push_cert.len)
 630                 return;
 631
 632         if (!already_done) {
 633                 int bogs /* beginning_of_gpg_sig */;
 634
 635                 already_done = 1;
 636                 if (write_object_file(push_cert.buf, push_cert.len, "blob",
 637                                       &push_cert_oid))
 638                         oidclr(&push_cert_oid);
 639
 640                 memset(&sigcheck, '\0', sizeof(sigcheck));
 641
 642                 bogs = parse_signature(push_cert.buf, push_cert.len);
 643                 check_signature(push_cert.buf, bogs, push_cert.buf + bogs,
 644                                 push_cert.len - bogs, &sigcheck);
 645
 646                 nonce_status = check_nonce(push_cert.buf, bogs);
 647         }
 648         if (!is_null_oid(&push_cert_oid)) {
 649                 argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT=%s",
 650                                  oid_to_hex(&push_cert_oid));
 651                 argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_SIGNER=%s",
 652                                  sigcheck.signer ? sigcheck.signer : "");
 653                 argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_KEY=%s",
 654                                  sigcheck.key ? sigcheck.key : "");
 655                 argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_STATUS=%c",
 656                                  sigcheck.result);
 657                 if (push_cert_nonce) {
 658                         argv_array_pushf(&proc->env_array,
 659                                          "GIT_PUSH_CERT_NONCE=%s",
 660                                          push_cert_nonce);
 661                         argv_array_pushf(&proc->env_array,
 662                                          "GIT_PUSH_CERT_NONCE_STATUS=%s",
 663                                          nonce_status);
 664                         if (nonce_status == NONCE_SLOP)
 665                                 argv_array_pushf(&proc->env_array,
 666                                                  "GIT_PUSH_CERT_NONCE_SLOP=%ld",
 667                                                  nonce_stamp_slop);
 668                 }
 669         }
 670 }
 671
 672 struct receive_hook_feed_state {
 673         struct command *cmd;
 674         int skip_broken;
 675         struct strbuf buf;
 676         const struct string_list *push_options;
 677 };
 678
 679 typedef int (*feed_fn)(void *, const char **, size_t *);
 680 static int run_and_feed_hook(const char *hook_name, feed_fn feed,
 681                              struct receive_hook_feed_state *feed_state)
 682 {
 683         struct child_process proc = CHILD_PROCESS_INIT;
 684         struct async muxer;
 685         const char *argv[2];
 686         int code;
 687
 688         argv[0] = find_hook(hook_name);
 689         if (!argv[0])
 690                 return 0;
 691
 692         argv[1] = NULL;
 693
 694         proc.argv = argv;
 695         proc.in = -1;
 696         proc.stdout_to_stderr = 1;
 697         proc.trace2_hook_name = hook_name;
 698
 699         if (feed_state->push_options) {
 700                 int i;
 701                 for (i = 0; i < feed_state->push_options->nr; i++)
 702                         argv_array_pushf(&proc.env_array,
 703                                 "GIT_PUSH_OPTION_%d=%s", i,
 704                                 feed_state->push_options->items[i].string);
 705                 argv_array_pushf(&proc.env_array, "GIT_PUSH_OPTION_COUNT=%d",
 706                                  feed_state->push_options->nr);
 707         } else
 708                 argv_array_pushf(&proc.env_array, "GIT_PUSH_OPTION_COUNT");
 709
 710         if (tmp_objdir)
 711                 argv_array_pushv(&proc.env_array, tmp_objdir_env(tmp_objdir));
 712
 713         if (use_sideband) {
 714                 memset(&muxer, 0, sizeof(muxer));
 715                 muxer.proc = copy_to_sideband;
 716                 muxer.in = -1;
 717                 code = start_async(&muxer);
 718                 if (code)
 719                         return code;
 720                 proc.err = muxer.in;
 721         }
 722
 723         prepare_push_cert_sha1(&proc);
 724
 725         code = start_command(&proc);
 726         if (code) {
 727                 if (use_sideband)
 728                         finish_async(&muxer);
 729                 return code;
 730         }
 731
 732         sigchain_push(SIGPIPE, SIG_IGN);
 733
 734         while (1) {
 735                 const char *buf;
 736                 size_t n;
 737                 if (feed(feed_state, &buf, &n))
 738                         break;
 739                 if (write_in_full(proc.in, buf, n) < 0)
 740                         break;
 741         }
 742         close(proc.in);
 743         if (use_sideband)
 744                 finish_async(&muxer);
 745
 746         sigchain_pop(SIGPIPE);
 747
 748         return finish_command(&proc);
 749 }
 750
 751 static int feed_receive_hook(void *state_, const char **bufp, size_t *sizep)
 752 {
 753         struct receive_hook_feed_state *state = state_;
 754         struct command *cmd = state->cmd;
 755
 756         while (cmd &&
 757                state->skip_broken && (cmd->error_string || cmd->did_not_exist))
 758                 cmd = cmd->next;
 759         if (!cmd)
 760                 return -1; /* EOF */
 761         strbuf_reset(&state->buf);
 762         strbuf_addf(&state->buf, "%s %s %s\n",
 763                     oid_to_hex(&cmd->old_oid), oid_to_hex(&cmd->new_oid),
 764                     cmd->ref_name);
 765         state->cmd = cmd->next;
 766         if (bufp) {
 767                 *bufp = state->buf.buf;
 768                 *sizep = state->buf.len;
 769         }
 770         return 0;
 771 }
 772
 773 static int run_receive_hook(struct command *commands,
 774                             const char *hook_name,
 775                             int skip_broken,
 776                             const struct string_list *push_options)
 777 {
 778         struct receive_hook_feed_state state;
 779         int status;
 780
 781         strbuf_init(&state.buf, 0);
 782         state.cmd = commands;
 783         state.skip_broken = skip_broken;
 784         if (feed_receive_hook(&state, NULL, NULL))
 785                 return 0;
 786         state.cmd = commands;
 787         state.push_options = push_options;
 788         status = run_and_feed_hook(hook_name, feed_receive_hook, &state);
 789         strbuf_release(&state.buf);
 790         return status;
 791 }
 792
 793 static int run_update_hook(struct command *cmd)
 794 {
 795         const char *argv[5];
 796         struct child_process proc = CHILD_PROCESS_INIT;
 797         int code;
 798
 799         argv[0] = find_hook("update");
 800         if (!argv[0])
 801                 return 0;
 802
 803         argv[1] = cmd->ref_name;
 804         argv[2] = oid_to_hex(&cmd->old_oid);
 805         argv[3] = oid_to_hex(&cmd->new_oid);
 806         argv[4] = NULL;
 807
 808         proc.no_stdin = 1;
 809         proc.stdout_to_stderr = 1;
 810         proc.err = use_sideband ? -1 : 0;
 811         proc.argv = argv;
 812         proc.trace2_hook_name = "update";
 813
 814         code = start_command(&proc);
 815         if (code)
 816                 return code;
 817         if (use_sideband)
 818                 copy_to_sideband(proc.err, -1, NULL);
 819         return finish_command(&proc);
 820 }
 821
 822 static int is_ref_checked_out(const char *ref)
 823 {
 824         if (is_bare_repository())
 825                 return 0;
 826
 827         if (!head_name)
 828                 return 0;
 829         return !strcmp(head_name, ref);
 830 }
 831
 832 static char *refuse_unconfigured_deny_msg =
 833         N_("By default, updating the current branch in a non-bare repository\n"
 834            "is denied, because it will make the index and work tree inconsistent\n"
 835            "with what you pushed, and will require 'git reset --hard' to match\n"
 836            "the work tree to HEAD.\n"
 837            "\n"
 838            "You can set the 'receive.denyCurrentBranch' configuration variable\n"
 839            "to 'ignore' or 'warn' in the remote repository to allow pushing into\n"
 840            "its current branch; however, this is not recommended unless you\n"
 841            "arranged to update its work tree to match what you pushed in some\n"
 842            "other way.\n"
 843            "\n"
 844            "To squelch this message and still keep the default behaviour, set\n"
 845            "'receive.denyCurrentBranch' configuration variable to 'refuse'.");
 846
 847 static void refuse_unconfigured_deny(void)
 848 {
 849         rp_error("%s", _(refuse_unconfigured_deny_msg));
 850 }
 851
 852 static char *refuse_unconfigured_deny_delete_current_msg =
 853         N_("By default, deleting the current branch is denied, because the next\n"
 854            "'git clone' won't result in any file checked out, causing confusion.\n"
 855            "\n"
 856            "You can set 'receive.denyDeleteCurrent' configuration variable to\n"
 857            "'warn' or 'ignore' in the remote repository to allow deleting the\n"
 858            "current branch, with or without a warning message.\n"
 859            "\n"
 860            "To squelch this message, you can set it to 'refuse'.");
 861
 862 static void refuse_unconfigured_deny_delete_current(void)
 863 {
 864         rp_error("%s", _(refuse_unconfigured_deny_delete_current_msg));
 865 }
 866
 867 static int command_singleton_iterator(void *cb_data, struct object_id *oid);
 868 static int update_shallow_ref(struct command *cmd, struct shallow_info *si)
 869 {
 870         struct lock_file shallow_lock = LOCK_INIT;
 871         struct oid_array extra = OID_ARRAY_INIT;
 872         struct check_connected_options opt = CHECK_CONNECTED_INIT;
 873         uint32_t mask = 1 << (cmd->index % 32);
 874         int i;
 875
 876         trace_printf_key(&trace_shallow,
 877                          "shallow: update_shallow_ref %s\n", cmd->ref_name);
 878         for (i = 0; i < si->shallow->nr; i++)
 879                 if (si->used_shallow[i] &&
 880                     (si->used_shallow[i][cmd->index / 32] & mask) &&
 881                     !delayed_reachability_test(si, i))
 882                         oid_array_append(&extra, &si->shallow->oid[i]);
 883
 884         opt.env = tmp_objdir_env(tmp_objdir);
 885         setup_alternate_shallow(&shallow_lock, &opt.shallow_file, &extra);
 886         if (check_connected(command_singleton_iterator, cmd, &opt)) {
 887                 rollback_lock_file(&shallow_lock);
 888                 oid_array_clear(&extra);
 889                 return -1;
 890         }
 891
 892         commit_lock_file(&shallow_lock);
 893
 894         /*
 895          * Make sure setup_alternate_shallow() for the next ref does
 896          * not lose these new roots..
 897          */
 898         for (i = 0; i < extra.nr; i++)
 899                 register_shallow(the_repository, &extra.oid[i]);
 900
 901         si->shallow_ref[cmd->index] = 0;
 902         oid_array_clear(&extra);
 903         return 0;
 904 }
 905
 906 /*
 907  * NEEDSWORK: we should consolidate various implementions of "are we
 908  * on an unborn branch?" test into one, and make the unified one more
 909  * robust. !get_sha1() based check used here and elsewhere would not
 910  * allow us to tell an unborn branch from corrupt ref, for example.
 911  * For the purpose of fixing "deploy-to-update does not work when
 912  * pushing into an empty repository" issue, this should suffice for
 913  * now.
 914  */
 915 static int head_has_history(void)
 916 {
 917         struct object_id oid;
 918
 919         return !get_oid("HEAD", &oid);
 920 }
 921
 922 static const char *push_to_deploy(unsigned char *sha1,
 923                                   struct argv_array *env,
 924                                   const char *work_tree)
 925 {
 926         const char *update_refresh[] = {
 927                 "update-index", "-q", "--ignore-submodules", "--refresh", NULL
 928         };
 929         const char *diff_files[] = {
 930                 "diff-files", "--quiet", "--ignore-submodules", "--", NULL
 931         };
 932         const char *diff_index[] = {
 933                 "diff-index", "--quiet", "--cached", "--ignore-submodules",
 934                 NULL, "--", NULL
 935         };
 936         const char *read_tree[] = {
 937                 "read-tree", "-u", "-m", NULL, NULL
 938         };
 939         struct child_process child = CHILD_PROCESS_INIT;
 940
 941         child.argv = update_refresh;
 942         child.env = env->argv;
 943         child.dir = work_tree;
 944         child.no_stdin = 1;
 945         child.stdout_to_stderr = 1;
 946         child.git_cmd = 1;
 947         if (run_command(&child))
 948                 return "Up-to-date check failed";
 949
 950         /* run_command() does not clean up completely; reinitialize */
 951         child_process_init(&child);
 952         child.argv = diff_files;
 953         child.env = env->argv;
 954         child.dir = work_tree;
 955         child.no_stdin = 1;
 956         child.stdout_to_stderr = 1;
 957         child.git_cmd = 1;
 958         if (run_command(&child))
 959                 return "Working directory has unstaged changes";
 960
 961         /* diff-index with either HEAD or an empty tree */
 962         diff_index[4] = head_has_history() ? "HEAD" : empty_tree_oid_hex();
 963
 964         child_process_init(&child);
 965         child.argv = diff_index;
 966         child.env = env->argv;
 967         child.no_stdin = 1;
 968         child.no_stdout = 1;
 969         child.stdout_to_stderr = 0;
 970         child.git_cmd = 1;
 971         if (run_command(&child))
 972                 return "Working directory has staged changes";
 973
 974         read_tree[3] = sha1_to_hex(sha1);
 975         child_process_init(&child);
 976         child.argv = read_tree;
 977         child.env = env->argv;
 978         child.dir = work_tree;
 979         child.no_stdin = 1;
 980         child.no_stdout = 1;
 981         child.stdout_to_stderr = 0;
 982         child.git_cmd = 1;
 983         if (run_command(&child))
 984                 return "Could not update working tree to new HEAD";
 985
 986         return NULL;
 987 }
 988
 989 static const char *push_to_checkout_hook = "push-to-checkout";
 990
 991 static const char *push_to_checkout(unsigned char *sha1,
 992                                     struct argv_array *env,
 993                                     const char *work_tree)
 994 {
 995         argv_array_pushf(env, "GIT_WORK_TREE=%s", absolute_path(work_tree));
 996         if (run_hook_le(env->argv, push_to_checkout_hook,
 997                         sha1_to_hex(sha1), NULL))
 998                 return "push-to-checkout hook declined";
 999         else
1000                 return NULL;
1001 }
1002
1003 static const char *update_worktree(unsigned char *sha1)
1004 {
1005         const char *retval;
1006         const char *work_tree = git_work_tree_cfg ? git_work_tree_cfg : "..";
1007         struct argv_array env = ARGV_ARRAY_INIT;
1008
1009         if (is_bare_repository())
1010                 return "denyCurrentBranch = updateInstead needs a worktree";
1011
1012         argv_array_pushf(&env, "GIT_DIR=%s", absolute_path(get_git_dir()));
1013
1014         if (!find_hook(push_to_checkout_hook))
1015                 retval = push_to_deploy(sha1, &env, work_tree);
1016         else
1017                 retval = push_to_checkout(sha1, &env, work_tree);
1018
1019         argv_array_clear(&env);
1020         return retval;
1021 }
1022
1023 static const char *update(struct command *cmd, struct shallow_info *si)
1024 {
1025         const char *name = cmd->ref_name;
1026         struct strbuf namespaced_name_buf = STRBUF_INIT;
1027         static char *namespaced_name;
1028         const char *ret;
1029         struct object_id *old_oid = &cmd->old_oid;
1030         struct object_id *new_oid = &cmd->new_oid;
1031         int do_update_worktree = 0;
1032
1033         /* only refs/... are allowed */
1034         if (!starts_with(name, "refs/") || check_refname_format(name + 5, 0)) {
1035                 rp_error("refusing to create funny ref '%s' remotely", name);
1036                 return "funny refname";
1037         }
1038
1039         strbuf_addf(&namespaced_name_buf, "%s%s", get_git_namespace(), name);
1040         free(namespaced_name);
1041         namespaced_name = strbuf_detach(&namespaced_name_buf, NULL);
1042
1043         if (is_ref_checked_out(namespaced_name)) {
1044                 switch (deny_current_branch) {
1045                 case DENY_IGNORE:
1046                         break;
1047                 case DENY_WARN:
1048                         rp_warning("updating the current branch");
1049                         break;
1050                 case DENY_REFUSE:
1051                 case DENY_UNCONFIGURED:
1052                         rp_error("refusing to update checked out branch: %s", name);
1053                         if (deny_current_branch == DENY_UNCONFIGURED)
1054                                 refuse_unconfigured_deny();
1055                         return "branch is currently checked out";
1056                 case DENY_UPDATE_INSTEAD:
1057                         /* pass -- let other checks intervene first */
1058                         do_update_worktree = 1;
1059                         break;
1060                 }
1061         }
1062
1063         if (!is_null_oid(new_oid) && !has_object_file(new_oid)) {
1064                 error("unpack should have generated %s, "
1065                       "but I can't find it!", oid_to_hex(new_oid));
1066                 return "bad pack";
1067         }
1068
1069         if (!is_null_oid(old_oid) && is_null_oid(new_oid)) {
1070                 if (deny_deletes && starts_with(name, "refs/heads/")) {
1071                         rp_error("denying ref deletion for %s", name);
1072                         return "deletion prohibited";
1073                 }
1074
1075                 if (head_name && !strcmp(namespaced_name, head_name)) {
1076                         switch (deny_delete_current) {
1077                         case DENY_IGNORE:
1078                                 break;
1079                         case DENY_WARN:
1080                                 rp_warning("deleting the current branch");
1081                                 break;
1082                         case DENY_REFUSE:
1083                         case DENY_UNCONFIGURED:
1084                         case DENY_UPDATE_INSTEAD:
1085                                 if (deny_delete_current == DENY_UNCONFIGURED)
1086                                         refuse_unconfigured_deny_delete_current();
1087                                 rp_error("refusing to delete the current branch: %s", name);
1088                                 return "deletion of the current branch prohibited";
1089                         default:
1090                                 return "Invalid denyDeleteCurrent setting";
1091                         }
1092                 }
1093         }
1094
1095         if (deny_non_fast_forwards && !is_null_oid(new_oid) &&
1096             !is_null_oid(old_oid) &&
1097             starts_with(name, "refs/heads/")) {
1098                 struct object *old_object, *new_object;
1099                 struct commit *old_commit, *new_commit;
1100
1101                 old_object = parse_object(the_repository, old_oid);
1102                 new_object = parse_object(the_repository, new_oid);
1103
1104                 if (!old_object || !new_object ||
1105                     old_object->type != OBJ_COMMIT ||
1106                     new_object->type != OBJ_COMMIT) {
1107                         error("bad sha1 objects for %s", name);
1108                         return "bad ref";
1109                 }
1110                 old_commit = (struct commit *)old_object;
1111                 new_commit = (struct commit *)new_object;
1112                 if (!in_merge_bases(old_commit, new_commit)) {
1113                         rp_error("denying non-fast-forward %s"
1114                                  " (you should pull first)", name);
1115                         return "non-fast-forward";
1116                 }
1117         }
1118         if (run_update_hook(cmd)) {
1119                 rp_error("hook declined to update %s", name);
1120                 return "hook declined";
1121         }
1122
1123         if (do_update_worktree) {
1124                 ret = update_worktree(new_oid->hash);
1125                 if (ret)
1126                         return ret;
1127         }
1128
1129         if (is_null_oid(new_oid)) {
1130                 struct strbuf err = STRBUF_INIT;
1131                 if (!parse_object(the_repository, old_oid)) {
1132                         old_oid = NULL;
1133                         if (ref_exists(name)) {
1134                                 rp_warning("Allowing deletion of corrupt ref.");
1135                         } else {
1136                                 rp_warning("Deleting a non-existent ref.");
1137                                 cmd->did_not_exist = 1;
1138                         }
1139                 }
1140                 if (ref_transaction_delete(transaction,
1141                                            namespaced_name,
1142                                            old_oid,
1143                                            0, "push", &err)) {
1144                         rp_error("%s", err.buf);
1145                         strbuf_release(&err);
1146                         return "failed to delete";
1147                 }
1148                 strbuf_release(&err);
1149                 return NULL; /* good */
1150         }
1151         else {
1152                 struct strbuf err = STRBUF_INIT;
1153                 if (shallow_update && si->shallow_ref[cmd->index] &&
1154                     update_shallow_ref(cmd, si))
1155                         return "shallow error";
1156
1157                 if (ref_transaction_update(transaction,
1158                                            namespaced_name,
1159                                            new_oid, old_oid,
1160                                            0, "push",
1161                                            &err)) {
1162                         rp_error("%s", err.buf);
1163                         strbuf_release(&err);
1164
1165                         return "failed to update ref";
1166                 }
1167                 strbuf_release(&err);
1168
1169                 return NULL; /* good */
1170         }
1171 }
1172
1173 static void run_update_post_hook(struct command *commands)
1174 {
1175         struct command *cmd;
1176         struct child_process proc = CHILD_PROCESS_INIT;
1177         const char *hook;
1178
1179         hook = find_hook("post-update");
1180         if (!hook)
1181                 return;
1182
1183         for (cmd = commands; cmd; cmd = cmd->next) {
1184                 if (cmd->error_string || cmd->did_not_exist)
1185                         continue;
1186                 if (!proc.args.argc)
1187                         argv_array_push(&proc.args, hook);
1188                 argv_array_push(&proc.args, cmd->ref_name);
1189         }
1190         if (!proc.args.argc)
1191                 return;
1192
1193         proc.no_stdin = 1;
1194         proc.stdout_to_stderr = 1;
1195         proc.err = use_sideband ? -1 : 0;
1196         proc.trace2_hook_name = "post-update";
1197
1198         if (!start_command(&proc)) {
1199                 if (use_sideband)
1200                         copy_to_sideband(proc.err, -1, NULL);
1201                 finish_command(&proc);
1202         }
1203 }
1204
1205 static void check_aliased_update_internal(struct command *cmd,
1206                                           struct string_list *list,
1207                                           const char *dst_name, int flag)
1208 {
1209         struct string_list_item *item;
1210         struct command *dst_cmd;
1211
1212         if (!(flag & REF_ISSYMREF))
1213                 return;
1214
1215         if (!dst_name) {
1216                 rp_error("refusing update to broken symref '%s'", cmd->ref_name);
1217                 cmd->skip_update = 1;
1218                 cmd->error_string = "broken symref";
1219                 return;
1220         }
1221         dst_name = strip_namespace(dst_name);
1222
1223         if ((item = string_list_lookup(list, dst_name)) == NULL)
1224                 return;
1225
1226         cmd->skip_update = 1;
1227
1228         dst_cmd = (struct command *) item->util;
1229
1230         if (oideq(&cmd->old_oid, &dst_cmd->old_oid) &&
1231             oideq(&cmd->new_oid, &dst_cmd->new_oid))
1232                 return;
1233
1234         dst_cmd->skip_update = 1;
1235
1236         rp_error("refusing inconsistent update between symref '%s' (%s..%s) and"
1237                  " its target '%s' (%s..%s)",
1238                  cmd->ref_name,
1239                  find_unique_abbrev(&cmd->old_oid, DEFAULT_ABBREV),
1240                  find_unique_abbrev(&cmd->new_oid, DEFAULT_ABBREV),
1241                  dst_cmd->ref_name,
1242                  find_unique_abbrev(&dst_cmd->old_oid, DEFAULT_ABBREV),
1243                  find_unique_abbrev(&dst_cmd->new_oid, DEFAULT_ABBREV));
1244
1245         cmd->error_string = dst_cmd->error_string =
1246                 "inconsistent aliased update";
1247 }
1248
1249 static void check_aliased_update(struct command *cmd, struct string_list *list)
1250 {
1251         struct strbuf buf = STRBUF_INIT;
1252         const char *dst_name;
1253         int flag;
1254
1255         strbuf_addf(&buf, "%s%s", get_git_namespace(), cmd->ref_name);
1256         dst_name = resolve_ref_unsafe(buf.buf, 0, NULL, &flag);
1257         check_aliased_update_internal(cmd, list, dst_name, flag);
1258         strbuf_release(&buf);
1259 }
1260
1261 static void check_aliased_updates(struct command *commands)
1262 {
1263         struct command *cmd;
1264         struct string_list ref_list = STRING_LIST_INIT_NODUP;
1265
1266         for (cmd = commands; cmd; cmd = cmd->next) {
1267                 struct string_list_item *item =
1268                         string_list_append(&ref_list, cmd->ref_name);
1269                 item->util = (void *)cmd;
1270         }
1271         string_list_sort(&ref_list);
1272
1273         for (cmd = commands; cmd; cmd = cmd->next) {
1274                 if (!cmd->error_string)
1275                         check_aliased_update(cmd, &ref_list);
1276         }
1277
1278         string_list_clear(&ref_list, 0);
1279 }
1280
1281 static int command_singleton_iterator(void *cb_data, struct object_id *oid)
1282 {
1283         struct command **cmd_list = cb_data;
1284         struct command *cmd = *cmd_list;
1285
1286         if (!cmd || is_null_oid(&cmd->new_oid))
1287                 return -1; /* end of list */
1288         *cmd_list = NULL; /* this returns only one */
1289         oidcpy(oid, &cmd->new_oid);
1290         return 0;
1291 }
1292
1293 static void set_connectivity_errors(struct command *commands,
1294                                     struct shallow_info *si)
1295 {
1296         struct command *cmd;
1297
1298         for (cmd = commands; cmd; cmd = cmd->next) {
1299                 struct command *singleton = cmd;
1300                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
1301
1302                 if (shallow_update && si->shallow_ref[cmd->index])
1303                         /* to be checked in update_shallow_ref() */
1304                         continue;
1305
1306                 opt.env = tmp_objdir_env(tmp_objdir);
1307                 if (!check_connected(command_singleton_iterator, &singleton,
1308                                      &opt))
1309                         continue;
1310
1311                 cmd->error_string = "missing necessary objects";
1312         }
1313 }
1314
1315 struct iterate_data {
1316         struct command *cmds;
1317         struct shallow_info *si;
1318 };
1319
1320 static int iterate_receive_command_list(void *cb_data, struct object_id *oid)
1321 {
1322         struct iterate_data *data = cb_data;
1323         struct command **cmd_list = &data->cmds;
1324         struct command *cmd = *cmd_list;
1325
1326         for (; cmd; cmd = cmd->next) {
1327                 if (shallow_update && data->si->shallow_ref[cmd->index])
1328                         /* to be checked in update_shallow_ref() */
1329                         continue;
1330                 if (!is_null_oid(&cmd->new_oid) && !cmd->skip_update) {
1331                         oidcpy(oid, &cmd->new_oid);
1332                         *cmd_list = cmd->next;
1333                         return 0;
1334                 }
1335         }
1336         *cmd_list = NULL;
1337         return -1; /* end of list */
1338 }
1339
1340 static void reject_updates_to_hidden(struct command *commands)
1341 {
1342         struct strbuf refname_full = STRBUF_INIT;
1343         size_t prefix_len;
1344         struct command *cmd;
1345
1346         strbuf_addstr(&refname_full, get_git_namespace());
1347         prefix_len = refname_full.len;
1348
1349         for (cmd = commands; cmd; cmd = cmd->next) {
1350                 if (cmd->error_string)
1351                         continue;
1352
1353                 strbuf_setlen(&refname_full, prefix_len);
1354                 strbuf_addstr(&refname_full, cmd->ref_name);
1355
1356                 if (!ref_is_hidden(cmd->ref_name, refname_full.buf))
1357                         continue;
1358                 if (is_null_oid(&cmd->new_oid))
1359                         cmd->error_string = "deny deleting a hidden ref";
1360                 else
1361                         cmd->error_string = "deny updating a hidden ref";
1362         }
1363
1364         strbuf_release(&refname_full);
1365 }
1366
1367 static int should_process_cmd(struct command *cmd)
1368 {
1369         return !cmd->error_string && !cmd->skip_update;
1370 }
1371
1372 static void warn_if_skipped_connectivity_check(struct command *commands,
1373                                                struct shallow_info *si)
1374 {
1375         struct command *cmd;
1376         int checked_connectivity = 1;
1377
1378         for (cmd = commands; cmd; cmd = cmd->next) {
1379                 if (should_process_cmd(cmd) && si->shallow_ref[cmd->index]) {
1380                         error("BUG: connectivity check has not been run on ref %s",
1381                               cmd->ref_name);
1382                         checked_connectivity = 0;
1383                 }
1384         }
1385         if (!checked_connectivity)
1386                 BUG("connectivity check skipped???");
1387 }
1388
1389 static void execute_commands_non_atomic(struct command *commands,
1390                                         struct shallow_info *si)
1391 {
1392         struct command *cmd;
1393         struct strbuf err = STRBUF_INIT;
1394
1395         for (cmd = commands; cmd; cmd = cmd->next) {
1396                 if (!should_process_cmd(cmd))
1397                         continue;
1398
1399                 transaction = ref_transaction_begin(&err);
1400                 if (!transaction) {
1401                         rp_error("%s", err.buf);
1402                         strbuf_reset(&err);
1403                         cmd->error_string = "transaction failed to start";
1404                         continue;
1405                 }
1406
1407                 cmd->error_string = update(cmd, si);
1408
1409                 if (!cmd->error_string
1410                     && ref_transaction_commit(transaction, &err)) {
1411                         rp_error("%s", err.buf);
1412                         strbuf_reset(&err);
1413                         cmd->error_string = "failed to update ref";
1414                 }
1415                 ref_transaction_free(transaction);
1416         }
1417         strbuf_release(&err);
1418 }
1419
1420 static void execute_commands_atomic(struct command *commands,
1421                                         struct shallow_info *si)
1422 {
1423         struct command *cmd;
1424         struct strbuf err = STRBUF_INIT;
1425         const char *reported_error = "atomic push failure";
1426
1427         transaction = ref_transaction_begin(&err);
1428         if (!transaction) {
1429                 rp_error("%s", err.buf);
1430                 strbuf_reset(&err);
1431                 reported_error = "transaction failed to start";
1432                 goto failure;
1433         }
1434
1435         for (cmd = commands; cmd; cmd = cmd->next) {
1436                 if (!should_process_cmd(cmd))
1437                         continue;
1438
1439                 cmd->error_string = update(cmd, si);
1440
1441                 if (cmd->error_string)
1442                         goto failure;
1443         }
1444
1445         if (ref_transaction_commit(transaction, &err)) {
1446                 rp_error("%s", err.buf);
1447                 reported_error = "atomic transaction failed";
1448                 goto failure;
1449         }
1450         goto cleanup;
1451
1452 failure:
1453         for (cmd = commands; cmd; cmd = cmd->next)
1454                 if (!cmd->error_string)
1455                         cmd->error_string = reported_error;
1456
1457 cleanup:
1458         ref_transaction_free(transaction);
1459         strbuf_release(&err);
1460 }
1461
1462 static void execute_commands(struct command *commands,
1463                              const char *unpacker_error,
1464                              struct shallow_info *si,
1465                              const struct string_list *push_options)
1466 {
1467         struct check_connected_options opt = CHECK_CONNECTED_INIT;
1468         struct command *cmd;
1469         struct iterate_data data;
1470         struct async muxer;
1471         int err_fd = 0;
1472
1473         if (unpacker_error) {
1474                 for (cmd = commands; cmd; cmd = cmd->next)
1475                         cmd->error_string = "unpacker error";
1476                 return;
1477         }
1478
1479         if (use_sideband) {
1480                 memset(&muxer, 0, sizeof(muxer));
1481                 muxer.proc = copy_to_sideband;
1482                 muxer.in = -1;
1483                 if (!start_async(&muxer))
1484                         err_fd = muxer.in;
1485                 /* ...else, continue without relaying sideband */
1486         }
1487
1488         data.cmds = commands;
1489         data.si = si;
1490         opt.err_fd = err_fd;
1491         opt.progress = err_fd && !quiet;
1492         opt.env = tmp_objdir_env(tmp_objdir);
1493         if (check_connected(iterate_receive_command_list, &data, &opt))
1494                 set_connectivity_errors(commands, si);
1495
1496         if (use_sideband)
1497                 finish_async(&muxer);
1498
1499         reject_updates_to_hidden(commands);
1500
1501         if (run_receive_hook(commands, "pre-receive", 0, push_options)) {
1502                 for (cmd = commands; cmd; cmd = cmd->next) {
1503                         if (!cmd->error_string)
1504                                 cmd->error_string = "pre-receive hook declined";
1505                 }
1506                 return;
1507         }
1508
1509         /*
1510          * Now we'll start writing out refs, which means the objects need
1511          * to be in their final positions so that other processes can see them.
1512          */
1513         if (tmp_objdir_migrate(tmp_objdir) < 0) {
1514                 for (cmd = commands; cmd; cmd = cmd->next) {
1515                         if (!cmd->error_string)
1516                                 cmd->error_string = "unable to migrate objects to permanent storage";
1517                 }
1518                 return;
1519         }
1520         tmp_objdir = NULL;
1521
1522         check_aliased_updates(commands);
1523
1524         free(head_name_to_free);
1525         head_name = head_name_to_free = resolve_refdup("HEAD", 0, NULL, NULL);
1526
1527         if (use_atomic)
1528                 execute_commands_atomic(commands, si);
1529         else
1530                 execute_commands_non_atomic(commands, si);
1531
1532         if (shallow_update)
1533                 warn_if_skipped_connectivity_check(commands, si);
1534 }
1535
1536 static struct command **queue_command(struct command **tail,
1537                                       const char *line,
1538                                       int linelen)
1539 {
1540         struct object_id old_oid, new_oid;
1541         struct command *cmd;
1542         const char *refname;
1543         int reflen;
1544         const char *p;
1545
1546         if (parse_oid_hex(line, &old_oid, &p) ||
1547             *p++ != ' ' ||
1548             parse_oid_hex(p, &new_oid, &p) ||
1549             *p++ != ' ')
1550                 die("protocol error: expected old/new/ref, got '%s'", line);
1551
1552         refname = p;
1553         reflen = linelen - (p - line);
1554         FLEX_ALLOC_MEM(cmd, ref_name, refname, reflen);
1555         oidcpy(&cmd->old_oid, &old_oid);
1556         oidcpy(&cmd->new_oid, &new_oid);
1557         *tail = cmd;
1558         return &cmd->next;
1559 }
1560
1561 static void queue_commands_from_cert(struct command **tail,
1562                                      struct strbuf *push_cert)
1563 {
1564         const char *boc, *eoc;
1565
1566         if (*tail)
1567                 die("protocol error: got both push certificate and unsigned commands");
1568
1569         boc = strstr(push_cert->buf, "\n\n");
1570         if (!boc)
1571                 die("malformed push certificate %.*s", 100, push_cert->buf);
1572         else
1573                 boc += 2;
1574         eoc = push_cert->buf + parse_signature(push_cert->buf, push_cert->len);
1575
1576         while (boc < eoc) {
1577                 const char *eol = memchr(boc, '\n', eoc - boc);
1578                 tail = queue_command(tail, boc, eol ? eol - boc : eoc - boc);
1579                 boc = eol ? eol + 1 : eoc;
1580         }
1581 }
1582
1583 static struct command *read_head_info(struct packet_reader *reader,
1584                                       struct oid_array *shallow)
1585 {
1586         struct command *commands = NULL;
1587         struct command **p = &commands;
1588         for (;;) {
1589                 int linelen;
1590
1591                 if (packet_reader_read(reader) != PACKET_READ_NORMAL)
1592                         break;
1593
1594                 if (reader->pktlen > 8 && starts_with(reader->line, "shallow ")) {
1595                         struct object_id oid;
1596                         if (get_oid_hex(reader->line + 8, &oid))
1597                                 die("protocol error: expected shallow sha, got '%s'",
1598                                     reader->line + 8);
1599                         oid_array_append(shallow, &oid);
1600                         continue;
1601                 }
1602
1603                 linelen = strlen(reader->line);
1604                 if (linelen < reader->pktlen) {
1605                         const char *feature_list = reader->line + linelen + 1;
1606                         if (parse_feature_request(feature_list, "report-status"))
1607                                 report_status = 1;
1608                         if (parse_feature_request(feature_list, "side-band-64k"))
1609                                 use_sideband = LARGE_PACKET_MAX;
1610                         if (parse_feature_request(feature_list, "quiet"))
1611                                 quiet = 1;
1612                         if (advertise_atomic_push
1613                             && parse_feature_request(feature_list, "atomic"))
1614                                 use_atomic = 1;
1615                         if (advertise_push_options
1616                             && parse_feature_request(feature_list, "push-options"))
1617                                 use_push_options = 1;
1618                 }
1619
1620                 if (!strcmp(reader->line, "push-cert")) {
1621                         int true_flush = 0;
1622                         int saved_options = reader->options;
1623                         reader->options &= ~PACKET_READ_CHOMP_NEWLINE;
1624
1625                         for (;;) {
1626                                 packet_reader_read(reader);
1627                                 if (reader->status == PACKET_READ_FLUSH) {
1628                                         true_flush = 1;
1629                                         break;
1630                                 }
1631                                 if (reader->status != PACKET_READ_NORMAL) {
1632                                         die("protocol error: got an unexpected packet");
1633                                 }
1634                                 if (!strcmp(reader->line, "push-cert-end\n"))
1635                                         break; /* end of cert */
1636                                 strbuf_addstr(&push_cert, reader->line);
1637                         }
1638                         reader->options = saved_options;
1639
1640                         if (true_flush)
1641                                 break;
1642                         continue;
1643                 }
1644
1645                 p = queue_command(p, reader->line, linelen);
1646         }
1647
1648         if (push_cert.len)
1649                 queue_commands_from_cert(p, &push_cert);
1650
1651         return commands;
1652 }
1653
1654 static void read_push_options(struct packet_reader *reader,
1655                               struct string_list *options)
1656 {
1657         while (1) {
1658                 if (packet_reader_read(reader) != PACKET_READ_NORMAL)
1659                         break;
1660
1661                 string_list_append(options, reader->line);
1662         }
1663 }
1664
1665 static const char *parse_pack_header(struct pack_header *hdr)
1666 {
1667         switch (read_pack_header(0, hdr)) {
1668         case PH_ERROR_EOF:
1669                 return "eof before pack header was fully read";
1670
1671         case PH_ERROR_PACK_SIGNATURE:
1672                 return "protocol error (pack signature mismatch detected)";
1673
1674         case PH_ERROR_PROTOCOL:
1675                 return "protocol error (pack version unsupported)";
1676
1677         default:
1678                 return "unknown error in parse_pack_header";
1679
1680         case 0:
1681                 return NULL;
1682         }
1683 }
1684
1685 static const char *pack_lockfile;
1686
1687 static void push_header_arg(struct argv_array *args, struct pack_header *hdr)
1688 {
1689         argv_array_pushf(args, "--pack_header=%"PRIu32",%"PRIu32,
1690                         ntohl(hdr->hdr_version), ntohl(hdr->hdr_entries));
1691 }
1692
1693 static const char *unpack(int err_fd, struct shallow_info *si)
1694 {
1695         struct pack_header hdr;
1696         const char *hdr_err;
1697         int status;
1698         struct child_process child = CHILD_PROCESS_INIT;
1699         int fsck_objects = (receive_fsck_objects >= 0
1700                             ? receive_fsck_objects
1701                             : transfer_fsck_objects >= 0
1702                             ? transfer_fsck_objects
1703                             : 0);
1704
1705         hdr_err = parse_pack_header(&hdr);
1706         if (hdr_err) {
1707                 if (err_fd > 0)
1708                         close(err_fd);
1709                 return hdr_err;
1710         }
1711
1712         if (si->nr_ours || si->nr_theirs) {
1713                 alt_shallow_file = setup_temporary_shallow(si->shallow);
1714                 argv_array_push(&child.args, "--shallow-file");
1715                 argv_array_push(&child.args, alt_shallow_file);
1716         }
1717
1718         tmp_objdir = tmp_objdir_create();
1719         if (!tmp_objdir) {
1720                 if (err_fd > 0)
1721                         close(err_fd);
1722                 return "unable to create temporary object directory";
1723         }
1724         child.env = tmp_objdir_env(tmp_objdir);
1725
1726         /*
1727          * Normally we just pass the tmp_objdir environment to the child
1728          * processes that do the heavy lifting, but we may need to see these
1729          * objects ourselves to set up shallow information.
1730          */
1731         tmp_objdir_add_as_alternate(tmp_objdir);
1732
1733         if (ntohl(hdr.hdr_entries) < unpack_limit) {
1734                 argv_array_push(&child.args, "unpack-objects");
1735                 push_header_arg(&child.args, &hdr);
1736                 if (quiet)
1737                         argv_array_push(&child.args, "-q");
1738                 if (fsck_objects)
1739                         argv_array_pushf(&child.args, "--strict%s",
1740                                 fsck_msg_types.buf);
1741                 if (max_input_size)
1742                         argv_array_pushf(&child.args, "--max-input-size=%"PRIuMAX,
1743                                 (uintmax_t)max_input_size);
1744                 child.no_stdout = 1;
1745                 child.err = err_fd;
1746                 child.git_cmd = 1;
1747                 status = run_command(&child);
1748                 if (status)
1749                         return "unpack-objects abnormal exit";
1750         } else {
1751                 char hostname[HOST_NAME_MAX + 1];
1752
1753                 argv_array_pushl(&child.args, "index-pack", "--stdin", NULL);
1754                 push_header_arg(&child.args, &hdr);
1755
1756                 if (xgethostname(hostname, sizeof(hostname)))
1757                         xsnprintf(hostname, sizeof(hostname), "localhost");
1758                 argv_array_pushf(&child.args,
1759                                  "--keep=receive-pack %"PRIuMAX" on %s",
1760                                  (uintmax_t)getpid(),
1761                                  hostname);
1762
1763                 if (!quiet && err_fd)
1764                         argv_array_push(&child.args, "--show-resolving-progress");
1765                 if (use_sideband)
1766                         argv_array_push(&child.args, "--report-end-of-input");
1767                 if (fsck_objects)
1768                         argv_array_pushf(&child.args, "--strict%s",
1769                                 fsck_msg_types.buf);
1770                 if (!reject_thin)
1771                         argv_array_push(&child.args, "--fix-thin");
1772                 if (max_input_size)
1773                         argv_array_pushf(&child.args, "--max-input-size=%"PRIuMAX,
1774                                 (uintmax_t)max_input_size);
1775                 child.out = -1;
1776                 child.err = err_fd;
1777                 child.git_cmd = 1;
1778                 status = start_command(&child);
1779                 if (status)
1780                         return "index-pack fork failed";
1781                 pack_lockfile = index_pack_lockfile(child.out);
1782                 close(child.out);
1783                 status = finish_command(&child);
1784                 if (status)
1785                         return "index-pack abnormal exit";
1786                 reprepare_packed_git(the_repository);
1787         }
1788         return NULL;
1789 }
1790
1791 static const char *unpack_with_sideband(struct shallow_info *si)
1792 {
1793         struct async muxer;
1794         const char *ret;
1795
1796         if (!use_sideband)
1797                 return unpack(0, si);
1798
1799         use_keepalive = KEEPALIVE_AFTER_NUL;
1800         memset(&muxer, 0, sizeof(muxer));
1801         muxer.proc = copy_to_sideband;
1802         muxer.in = -1;
1803         if (start_async(&muxer))
1804                 return NULL;
1805
1806         ret = unpack(muxer.in, si);
1807
1808         finish_async(&muxer);
1809         return ret;
1810 }
1811
1812 static void prepare_shallow_update(struct command *commands,
1813                                    struct shallow_info *si)
1814 {
1815         int i, j, k, bitmap_size = DIV_ROUND_UP(si->ref->nr, 32);
1816
1817         ALLOC_ARRAY(si->used_shallow, si->shallow->nr);
1818         assign_shallow_commits_to_refs(si, si->used_shallow, NULL);
1819
1820         si->need_reachability_test =
1821                 xcalloc(si->shallow->nr, sizeof(*si->need_reachability_test));
1822         si->reachable =
1823                 xcalloc(si->shallow->nr, sizeof(*si->reachable));
1824         si->shallow_ref = xcalloc(si->ref->nr, sizeof(*si->shallow_ref));
1825
1826         for (i = 0; i < si->nr_ours; i++)
1827                 si->need_reachability_test[si->ours[i]] = 1;
1828
1829         for (i = 0; i < si->shallow->nr; i++) {
1830                 if (!si->used_shallow[i])
1831                         continue;
1832                 for (j = 0; j < bitmap_size; j++) {
1833                         if (!si->used_shallow[i][j])
1834                                 continue;
1835                         si->need_reachability_test[i]++;
1836                         for (k = 0; k < 32; k++)
1837                                 if (si->used_shallow[i][j] & (1U << k))
1838                                         si->shallow_ref[j * 32 + k]++;
1839                 }
1840
1841                 /*
1842                  * true for those associated with some refs and belong
1843                  * in "ours" list aka "step 7 not done yet"
1844                  */
1845                 si->need_reachability_test[i] =
1846                         si->need_reachability_test[i] > 1;
1847         }
1848
1849         /*
1850          * keep hooks happy by forcing a temporary shallow file via
1851          * env variable because we can't add --shallow-file to every
1852          * command. check_connected() will be done with
1853          * true .git/shallow though.
1854          */
1855         setenv(GIT_SHALLOW_FILE_ENVIRONMENT, alt_shallow_file, 1);
1856 }
1857
1858 static void update_shallow_info(struct command *commands,
1859                                 struct shallow_info *si,
1860                                 struct oid_array *ref)
1861 {
1862         struct command *cmd;
1863         int *ref_status;
1864         remove_nonexistent_theirs_shallow(si);
1865         if (!si->nr_ours && !si->nr_theirs) {
1866                 shallow_update = 0;
1867                 return;
1868         }
1869
1870         for (cmd = commands; cmd; cmd = cmd->next) {
1871                 if (is_null_oid(&cmd->new_oid))
1872                         continue;
1873                 oid_array_append(ref, &cmd->new_oid);
1874                 cmd->index = ref->nr - 1;
1875         }
1876         si->ref = ref;
1877
1878         if (shallow_update) {
1879                 prepare_shallow_update(commands, si);
1880                 return;
1881         }
1882
1883         ALLOC_ARRAY(ref_status, ref->nr);
1884         assign_shallow_commits_to_refs(si, NULL, ref_status);
1885         for (cmd = commands; cmd; cmd = cmd->next) {
1886                 if (is_null_oid(&cmd->new_oid))
1887                         continue;
1888                 if (ref_status[cmd->index]) {
1889                         cmd->error_string = "shallow update not allowed";
1890                         cmd->skip_update = 1;
1891                 }
1892         }
1893         free(ref_status);
1894 }
1895
1896 static void report(struct command *commands, const char *unpack_status)
1897 {
1898         struct command *cmd;
1899         struct strbuf buf = STRBUF_INIT;
1900
1901         packet_buf_write(&buf, "unpack %s\n",
1902                          unpack_status ? unpack_status : "ok");
1903         for (cmd = commands; cmd; cmd = cmd->next) {
1904                 if (!cmd->error_string)
1905                         packet_buf_write(&buf, "ok %s\n",
1906                                          cmd->ref_name);
1907                 else
1908                         packet_buf_write(&buf, "ng %s %s\n",
1909                                          cmd->ref_name, cmd->error_string);
1910         }
1911         packet_buf_flush(&buf);
1912
1913         if (use_sideband)
1914                 send_sideband(1, 1, buf.buf, buf.len, use_sideband);
1915         else
1916                 write_or_die(1, buf.buf, buf.len);
1917         strbuf_release(&buf);
1918 }
1919
1920 static int delete_only(struct command *commands)
1921 {
1922         struct command *cmd;
1923         for (cmd = commands; cmd; cmd = cmd->next) {
1924                 if (!is_null_oid(&cmd->new_oid))
1925                         return 0;
1926         }
1927         return 1;
1928 }
1929
1930 int cmd_receive_pack(int argc, const char **argv, const char *prefix)
1931 {
1932         int advertise_refs = 0;
1933         struct command *commands;
1934         struct oid_array shallow = OID_ARRAY_INIT;
1935         struct oid_array ref = OID_ARRAY_INIT;
1936         struct shallow_info si;
1937         struct packet_reader reader;
1938
1939         struct option options[] = {
1940                 OPT__QUIET(&quiet, N_("quiet")),
1941                 OPT_HIDDEN_BOOL(0, "stateless-rpc", &stateless_rpc, NULL),
1942                 OPT_HIDDEN_BOOL(0, "advertise-refs", &advertise_refs, NULL),
1943                 OPT_HIDDEN_BOOL(0, "reject-thin-pack-for-testing", &reject_thin, NULL),
1944                 OPT_END()
1945         };
1946
1947         packet_trace_identity("receive-pack");
1948
1949         argc = parse_options(argc, argv, prefix, options, receive_pack_usage, 0);
1950
1951         if (argc > 1)
1952                 usage_msg_opt(_("Too many arguments."), receive_pack_usage, options);
1953         if (argc == 0)
1954                 usage_msg_opt(_("You must specify a directory."), receive_pack_usage, options);
1955
1956         service_dir = argv[0];
1957
1958         setup_path();
1959
1960         if (!enter_repo(service_dir, 0))
1961                 die("'%s' does not appear to be a git repository", service_dir);
1962
1963         git_config(receive_pack_config, NULL);
1964         if (cert_nonce_seed)
1965                 push_cert_nonce = prepare_push_cert_nonce(service_dir, time(NULL));
1966
1967         if (0 <= transfer_unpack_limit)
1968                 unpack_limit = transfer_unpack_limit;
1969         else if (0 <= receive_unpack_limit)
1970                 unpack_limit = receive_unpack_limit;
1971
1972         switch (determine_protocol_version_server()) {
1973         case protocol_v2:
1974                 /*
1975                  * push support for protocol v2 has not been implemented yet,
1976                  * so ignore the request to use v2 and fallback to using v0.
1977                  */
1978                 break;
1979         case protocol_v1:
1980                 /*
1981                  * v1 is just the original protocol with a version string,
1982                  * so just fall through after writing the version string.
1983                  */
1984                 if (advertise_refs || !stateless_rpc)
1985                         packet_write_fmt(1, "version 1\n");
1986
1987                 /* fallthrough */
1988         case protocol_v0:
1989                 break;
1990         case protocol_unknown_version:
1991                 BUG("unknown protocol version");
1992         }
1993
1994         if (advertise_refs || !stateless_rpc) {
1995                 write_head_info();
1996         }
1997         if (advertise_refs)
1998                 return 0;
1999
2000         packet_reader_init(&reader, 0, NULL, 0,
2001                            PACKET_READ_CHOMP_NEWLINE |
2002                            PACKET_READ_DIE_ON_ERR_PACKET);
2003
2004         if ((commands = read_head_info(&reader, &shallow)) != NULL) {
2005                 const char *unpack_status = NULL;
2006                 struct string_list push_options = STRING_LIST_INIT_DUP;
2007
2008                 if (use_push_options)
2009                         read_push_options(&reader, &push_options);
2010                 if (!check_cert_push_options(&push_options)) {
2011                         struct command *cmd;
2012                         for (cmd = commands; cmd; cmd = cmd->next)
2013                                 cmd->error_string = "inconsistent push options";
2014                 }
2015
2016                 prepare_shallow_info(&si, &shallow);
2017                 if (!si.nr_ours && !si.nr_theirs)
2018                         shallow_update = 0;
2019                 if (!delete_only(commands)) {
2020                         unpack_status = unpack_with_sideband(&si);
2021                         update_shallow_info(commands, &si, &ref);
2022                 }
2023                 use_keepalive = KEEPALIVE_ALWAYS;
2024                 execute_commands(commands, unpack_status, &si,
2025                                  &push_options);
2026                 if (pack_lockfile)
2027                         unlink_or_warn(pack_lockfile);
2028                 if (report_status)
2029                         report(commands, unpack_status);
2030                 run_receive_hook(commands, "post-receive", 1,
2031                                  &push_options);
2032                 run_update_post_hook(commands);
2033                 string_list_clear(&push_options, 0);
2034                 if (auto_gc) {
2035                         const char *argv_gc_auto[] = {
2036                                 "gc", "--auto", "--quiet", NULL,
2037                         };
2038                         struct child_process proc = CHILD_PROCESS_INIT;
2039
2040                         proc.no_stdin = 1;
2041                         proc.stdout_to_stderr = 1;
2042                         proc.err = use_sideband ? -1 : 0;
2043                         proc.git_cmd = 1;
2044                         proc.argv = argv_gc_auto;
2045
2046                         close_all_packs(the_repository->objects);
2047                         if (!start_command(&proc)) {
2048                                 if (use_sideband)
2049                                         copy_to_sideband(proc.err, -1, NULL);
2050                                 finish_command(&proc);
2051                         }
2052                 }
2053                 if (auto_update_server_info)
2054                         update_server_info(0);
2055                 clear_shallow_info(&si);
2056         }
2057         if (use_sideband)
2058                 packet_flush(1);
2059         oid_array_clear(&shallow);
2060         oid_array_clear(&ref);
2061         free((void *)push_cert_nonce);
2062         return 0;
2063 }