builtin/receive-pack.c

   1 #include "builtin.h"
   2 #include "config.h"
   3 #include "lockfile.h"
   4 #include "pack.h"
   5 #include "refs.h"
   6 #include "pkt-line.h"
   7 #include "sideband.h"
   8 #include "run-command.h"
   9 #include "exec_cmd.h"
  10 #include "commit.h"
  11 #include "object.h"
  12 #include "remote.h"
  13 #include "connect.h"
  14 #include "transport.h"
  15 #include "string-list.h"
  16 #include "sha1-array.h"
  17 #include "connected.h"
  18 #include "argv-array.h"
  19 #include "version.h"
  20 #include "tag.h"
  21 #include "gpg-interface.h"
  22 #include "sigchain.h"
  23 #include "fsck.h"
  24 #include "tmp-objdir.h"
  25 #include "oidset.h"
  26 #include "packfile.h"
  27 #include "protocol.h"
  28
  29 static const char * const receive_pack_usage[] = {
  30         N_("git receive-pack <git-dir>"),
  31         NULL
  32 };
  33
  34 enum deny_action {
  35         DENY_UNCONFIGURED,
  36         DENY_IGNORE,
  37         DENY_WARN,
  38         DENY_REFUSE,
  39         DENY_UPDATE_INSTEAD
  40 };
  41
  42 static int deny_deletes;
  43 static int deny_non_fast_forwards;
  44 static enum deny_action deny_current_branch = DENY_UNCONFIGURED;
  45 static enum deny_action deny_delete_current = DENY_UNCONFIGURED;
  46 static int receive_fsck_objects = -1;
  47 static int transfer_fsck_objects = -1;
  48 static struct strbuf fsck_msg_types = STRBUF_INIT;
  49 static int receive_unpack_limit = -1;
  50 static int transfer_unpack_limit = -1;
  51 static int advertise_atomic_push = 1;
  52 static int advertise_push_options;
  53 static int unpack_limit = 100;
  54 static off_t max_input_size;
  55 static int report_status;
  56 static int use_sideband;
  57 static int use_atomic;
  58 static int use_push_options;
  59 static int quiet;
  60 static int prefer_ofs_delta = 1;
  61 static int auto_update_server_info;
  62 static int auto_gc = 1;
  63 static int reject_thin;
  64 static int stateless_rpc;
  65 static const char *service_dir;
  66 static const char *head_name;
  67 static void *head_name_to_free;
  68 static int sent_capabilities;
  69 static int shallow_update;
  70 static const char *alt_shallow_file;
  71 static struct strbuf push_cert = STRBUF_INIT;
  72 static unsigned char push_cert_sha1[20];
  73 static struct signature_check sigcheck;
  74 static const char *push_cert_nonce;
  75 static const char *cert_nonce_seed;
  76
  77 static const char *NONCE_UNSOLICITED = "UNSOLICITED";
  78 static const char *NONCE_BAD = "BAD";
  79 static const char *NONCE_MISSING = "MISSING";
  80 static const char *NONCE_OK = "OK";
  81 static const char *NONCE_SLOP = "SLOP";
  82 static const char *nonce_status;
  83 static long nonce_stamp_slop;
  84 static timestamp_t nonce_stamp_slop_limit;
  85 static struct ref_transaction *transaction;
  86
  87 static enum {
  88         KEEPALIVE_NEVER = 0,
  89         KEEPALIVE_AFTER_NUL,
  90         KEEPALIVE_ALWAYS
  91 } use_keepalive;
  92 static int keepalive_in_sec = 5;
  93
  94 static struct tmp_objdir *tmp_objdir;
  95
  96 static enum deny_action parse_deny_action(const char *var, const char *value)
  97 {
  98         if (value) {
  99                 if (!strcasecmp(value, "ignore"))
 100                         return DENY_IGNORE;
 101                 if (!strcasecmp(value, "warn"))
 102                         return DENY_WARN;
 103                 if (!strcasecmp(value, "refuse"))
 104                         return DENY_REFUSE;
 105                 if (!strcasecmp(value, "updateinstead"))
 106                         return DENY_UPDATE_INSTEAD;
 107         }
 108         if (git_config_bool(var, value))
 109                 return DENY_REFUSE;
 110         return DENY_IGNORE;
 111 }
 112
 113 static int receive_pack_config(const char *var, const char *value, void *cb)
 114 {
 115         int status = parse_hide_refs_config(var, value, "receive");
 116
 117         if (status)
 118                 return status;
 119
 120         if (strcmp(var, "receive.denydeletes") == 0) {
 121                 deny_deletes = git_config_bool(var, value);
 122                 return 0;
 123         }
 124
 125         if (strcmp(var, "receive.denynonfastforwards") == 0) {
 126                 deny_non_fast_forwards = git_config_bool(var, value);
 127                 return 0;
 128         }
 129
 130         if (strcmp(var, "receive.unpacklimit") == 0) {
 131                 receive_unpack_limit = git_config_int(var, value);
 132                 return 0;
 133         }
 134
 135         if (strcmp(var, "transfer.unpacklimit") == 0) {
 136                 transfer_unpack_limit = git_config_int(var, value);
 137                 return 0;
 138         }
 139
 140         if (strcmp(var, "receive.fsck.skiplist") == 0) {
 141                 const char *path;
 142
 143                 if (git_config_pathname(&path, var, value))
 144                         return 1;
 145                 strbuf_addf(&fsck_msg_types, "%cskiplist=%s",
 146                         fsck_msg_types.len ? ',' : '=', path);
 147                 free((char *)path);
 148                 return 0;
 149         }
 150
 151         if (skip_prefix(var, "receive.fsck.", &var)) {
 152                 if (is_valid_msg_type(var, value))
 153                         strbuf_addf(&fsck_msg_types, "%c%s=%s",
 154                                 fsck_msg_types.len ? ',' : '=', var, value);
 155                 else
 156                         warning("Skipping unknown msg id '%s'", var);
 157                 return 0;
 158         }
 159
 160         if (strcmp(var, "receive.fsckobjects") == 0) {
 161                 receive_fsck_objects = git_config_bool(var, value);
 162                 return 0;
 163         }
 164
 165         if (strcmp(var, "transfer.fsckobjects") == 0) {
 166                 transfer_fsck_objects = git_config_bool(var, value);
 167                 return 0;
 168         }
 169
 170         if (!strcmp(var, "receive.denycurrentbranch")) {
 171                 deny_current_branch = parse_deny_action(var, value);
 172                 return 0;
 173         }
 174
 175         if (strcmp(var, "receive.denydeletecurrent") == 0) {
 176                 deny_delete_current = parse_deny_action(var, value);
 177                 return 0;
 178         }
 179
 180         if (strcmp(var, "repack.usedeltabaseoffset") == 0) {
 181                 prefer_ofs_delta = git_config_bool(var, value);
 182                 return 0;
 183         }
 184
 185         if (strcmp(var, "receive.updateserverinfo") == 0) {
 186                 auto_update_server_info = git_config_bool(var, value);
 187                 return 0;
 188         }
 189
 190         if (strcmp(var, "receive.autogc") == 0) {
 191                 auto_gc = git_config_bool(var, value);
 192                 return 0;
 193         }
 194
 195         if (strcmp(var, "receive.shallowupdate") == 0) {
 196                 shallow_update = git_config_bool(var, value);
 197                 return 0;
 198         }
 199
 200         if (strcmp(var, "receive.certnonceseed") == 0)
 201                 return git_config_string(&cert_nonce_seed, var, value);
 202
 203         if (strcmp(var, "receive.certnonceslop") == 0) {
 204                 nonce_stamp_slop_limit = git_config_ulong(var, value);
 205                 return 0;
 206         }
 207
 208         if (strcmp(var, "receive.advertiseatomic") == 0) {
 209                 advertise_atomic_push = git_config_bool(var, value);
 210                 return 0;
 211         }
 212
 213         if (strcmp(var, "receive.advertisepushoptions") == 0) {
 214                 advertise_push_options = git_config_bool(var, value);
 215                 return 0;
 216         }
 217
 218         if (strcmp(var, "receive.keepalive") == 0) {
 219                 keepalive_in_sec = git_config_int(var, value);
 220                 return 0;
 221         }
 222
 223         if (strcmp(var, "receive.maxinputsize") == 0) {
 224                 max_input_size = git_config_int64(var, value);
 225                 return 0;
 226         }
 227
 228         return git_default_config(var, value, cb);
 229 }
 230
 231 static void show_ref(const char *path, const struct object_id *oid)
 232 {
 233         if (sent_capabilities) {
 234                 packet_write_fmt(1, "%s %s\n", oid_to_hex(oid), path);
 235         } else {
 236                 struct strbuf cap = STRBUF_INIT;
 237
 238                 strbuf_addstr(&cap,
 239                               "report-status delete-refs side-band-64k quiet");
 240                 if (advertise_atomic_push)
 241                         strbuf_addstr(&cap, " atomic");
 242                 if (prefer_ofs_delta)
 243                         strbuf_addstr(&cap, " ofs-delta");
 244                 if (push_cert_nonce)
 245                         strbuf_addf(&cap, " push-cert=%s", push_cert_nonce);
 246                 if (advertise_push_options)
 247                         strbuf_addstr(&cap, " push-options");
 248                 strbuf_addf(&cap, " agent=%s", git_user_agent_sanitized());
 249                 packet_write_fmt(1, "%s %s%c%s\n",
 250                              oid_to_hex(oid), path, 0, cap.buf);
 251                 strbuf_release(&cap);
 252                 sent_capabilities = 1;
 253         }
 254 }
 255
 256 static int show_ref_cb(const char *path_full, const struct object_id *oid,
 257                        int flag, void *data)
 258 {
 259         struct oidset *seen = data;
 260         const char *path = strip_namespace(path_full);
 261
 262         if (ref_is_hidden(path, path_full))
 263                 return 0;
 264
 265         /*
 266          * Advertise refs outside our current namespace as ".have"
 267          * refs, so that the client can use them to minimize data
 268          * transfer but will otherwise ignore them.
 269          */
 270         if (!path) {
 271                 if (oidset_insert(seen, oid))
 272                         return 0;
 273                 path = ".have";
 274         } else {
 275                 oidset_insert(seen, oid);
 276         }
 277         show_ref(path, oid);
 278         return 0;
 279 }
 280
 281 static void show_one_alternate_ref(const char *refname,
 282                                    const struct object_id *oid,
 283                                    void *data)
 284 {
 285         struct oidset *seen = data;
 286
 287         if (oidset_insert(seen, oid))
 288                 return;
 289
 290         show_ref(".have", oid);
 291 }
 292
 293 static void write_head_info(void)
 294 {
 295         static struct oidset seen = OIDSET_INIT;
 296
 297         for_each_ref(show_ref_cb, &seen);
 298         for_each_alternate_ref(show_one_alternate_ref, &seen);
 299         oidset_clear(&seen);
 300         if (!sent_capabilities)
 301                 show_ref("capabilities^{}", &null_oid);
 302
 303         advertise_shallow_grafts(1);
 304
 305         /* EOF */
 306         packet_flush(1);
 307 }
 308
 309 struct command {
 310         struct command *next;
 311         const char *error_string;
 312         unsigned int skip_update:1,
 313                      did_not_exist:1;
 314         int index;
 315         struct object_id old_oid;
 316         struct object_id new_oid;
 317         char ref_name[FLEX_ARRAY]; /* more */
 318 };
 319
 320 static void rp_error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 321 static void rp_warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 322
 323 static void report_message(const char *prefix, const char *err, va_list params)
 324 {
 325         int sz;
 326         char msg[4096];
 327
 328         sz = xsnprintf(msg, sizeof(msg), "%s", prefix);
 329         sz += vsnprintf(msg + sz, sizeof(msg) - sz, err, params);
 330         if (sz > (sizeof(msg) - 1))
 331                 sz = sizeof(msg) - 1;
 332         msg[sz++] = '\n';
 333
 334         if (use_sideband)
 335                 send_sideband(1, 2, msg, sz, use_sideband);
 336         else
 337                 xwrite(2, msg, sz);
 338 }
 339
 340 static void rp_warning(const char *err, ...)
 341 {
 342         va_list params;
 343         va_start(params, err);
 344         report_message("warning: ", err, params);
 345         va_end(params);
 346 }
 347
 348 static void rp_error(const char *err, ...)
 349 {
 350         va_list params;
 351         va_start(params, err);
 352         report_message("error: ", err, params);
 353         va_end(params);
 354 }
 355
 356 static int copy_to_sideband(int in, int out, void *arg)
 357 {
 358         char data[128];
 359         int keepalive_active = 0;
 360
 361         if (keepalive_in_sec <= 0)
 362                 use_keepalive = KEEPALIVE_NEVER;
 363         if (use_keepalive == KEEPALIVE_ALWAYS)
 364                 keepalive_active = 1;
 365
 366         while (1) {
 367                 ssize_t sz;
 368
 369                 if (keepalive_active) {
 370                         struct pollfd pfd;
 371                         int ret;
 372
 373                         pfd.fd = in;
 374                         pfd.events = POLLIN;
 375                         ret = poll(&pfd, 1, 1000 * keepalive_in_sec);
 376
 377                         if (ret < 0) {
 378                                 if (errno == EINTR)
 379                                         continue;
 380                                 else
 381                                         break;
 382                         } else if (ret == 0) {
 383                                 /* no data; send a keepalive packet */
 384                                 static const char buf[] = "0005\1";
 385                                 write_or_die(1, buf, sizeof(buf) - 1);
 386                                 continue;
 387                         } /* else there is actual data to read */
 388                 }
 389
 390                 sz = xread(in, data, sizeof(data));
 391                 if (sz <= 0)
 392                         break;
 393
 394                 if (use_keepalive == KEEPALIVE_AFTER_NUL && !keepalive_active) {
 395                         const char *p = memchr(data, '\0', sz);
 396                         if (p) {
 397                                 /*
 398                                  * The NUL tells us to start sending keepalives. Make
 399                                  * sure we send any other data we read along
 400                                  * with it.
 401                                  */
 402                                 keepalive_active = 1;
 403                                 send_sideband(1, 2, data, p - data, use_sideband);
 404                                 send_sideband(1, 2, p + 1, sz - (p - data + 1), use_sideband);
 405                                 continue;
 406                         }
 407                 }
 408
 409                 /*
 410                  * Either we're not looking for a NUL signal, or we didn't see
 411                  * it yet; just pass along the data.
 412                  */
 413                 send_sideband(1, 2, data, sz, use_sideband);
 414         }
 415         close(in);
 416         return 0;
 417 }
 418
 419 #define HMAC_BLOCK_SIZE 64
 420
 421 static void hmac_sha1(unsigned char *out,
 422                       const char *key_in, size_t key_len,
 423                       const char *text, size_t text_len)
 424 {
 425         unsigned char key[HMAC_BLOCK_SIZE];
 426         unsigned char k_ipad[HMAC_BLOCK_SIZE];
 427         unsigned char k_opad[HMAC_BLOCK_SIZE];
 428         int i;
 429         git_SHA_CTX ctx;
 430
 431         /* RFC 2104 2. (1) */
 432         memset(key, '\0', HMAC_BLOCK_SIZE);
 433         if (HMAC_BLOCK_SIZE < key_len) {
 434                 git_SHA1_Init(&ctx);
 435                 git_SHA1_Update(&ctx, key_in, key_len);
 436                 git_SHA1_Final(key, &ctx);
 437         } else {
 438                 memcpy(key, key_in, key_len);
 439         }
 440
 441         /* RFC 2104 2. (2) & (5) */
 442         for (i = 0; i < sizeof(key); i++) {
 443                 k_ipad[i] = key[i] ^ 0x36;
 444                 k_opad[i] = key[i] ^ 0x5c;
 445         }
 446
 447         /* RFC 2104 2. (3) & (4) */
 448         git_SHA1_Init(&ctx);
 449         git_SHA1_Update(&ctx, k_ipad, sizeof(k_ipad));
 450         git_SHA1_Update(&ctx, text, text_len);
 451         git_SHA1_Final(out, &ctx);
 452
 453         /* RFC 2104 2. (6) & (7) */
 454         git_SHA1_Init(&ctx);
 455         git_SHA1_Update(&ctx, k_opad, sizeof(k_opad));
 456         git_SHA1_Update(&ctx, out, 20);
 457         git_SHA1_Final(out, &ctx);
 458 }
 459
 460 static char *prepare_push_cert_nonce(const char *path, timestamp_t stamp)
 461 {
 462         struct strbuf buf = STRBUF_INIT;
 463         unsigned char sha1[20];
 464
 465         strbuf_addf(&buf, "%s:%"PRItime, path, stamp);
 466         hmac_sha1(sha1, buf.buf, buf.len, cert_nonce_seed, strlen(cert_nonce_seed));;
 467         strbuf_release(&buf);
 468
 469         /* RFC 2104 5. HMAC-SHA1-80 */
 470         strbuf_addf(&buf, "%"PRItime"-%.*s", stamp, 20, sha1_to_hex(sha1));
 471         return strbuf_detach(&buf, NULL);
 472 }
 473
 474 /*
 475  * NEEDSWORK: reuse find_commit_header() from jk/commit-author-parsing
 476  * after dropping "_commit" from its name and possibly moving it out
 477  * of commit.c
 478  */
 479 static char *find_header(const char *msg, size_t len, const char *key,
 480                          const char **next_line)
 481 {
 482         int key_len = strlen(key);
 483         const char *line = msg;
 484
 485         while (line && line < msg + len) {
 486                 const char *eol = strchrnul(line, '\n');
 487
 488                 if ((msg + len <= eol) || line == eol)
 489                         return NULL;
 490                 if (line + key_len < eol &&
 491                     !memcmp(line, key, key_len) && line[key_len] == ' ') {
 492                         int offset = key_len + 1;
 493                         if (next_line)
 494                                 *next_line = *eol ? eol + 1 : eol;
 495                         return xmemdupz(line + offset, (eol - line) - offset);
 496                 }
 497                 line = *eol ? eol + 1 : NULL;
 498         }
 499         return NULL;
 500 }
 501
 502 static const char *check_nonce(const char *buf, size_t len)
 503 {
 504         char *nonce = find_header(buf, len, "nonce", NULL);
 505         timestamp_t stamp, ostamp;
 506         char *bohmac, *expect = NULL;
 507         const char *retval = NONCE_BAD;
 508
 509         if (!nonce) {
 510                 retval = NONCE_MISSING;
 511                 goto leave;
 512         } else if (!push_cert_nonce) {
 513                 retval = NONCE_UNSOLICITED;
 514                 goto leave;
 515         } else if (!strcmp(push_cert_nonce, nonce)) {
 516                 retval = NONCE_OK;
 517                 goto leave;
 518         }
 519
 520         if (!stateless_rpc) {
 521                 /* returned nonce MUST match what we gave out earlier */
 522                 retval = NONCE_BAD;
 523                 goto leave;
 524         }
 525
 526         /*
 527          * In stateless mode, we may be receiving a nonce issued by
 528          * another instance of the server that serving the same
 529          * repository, and the timestamps may not match, but the
 530          * nonce-seed and dir should match, so we can recompute and
 531          * report the time slop.
 532          *
 533          * In addition, when a nonce issued by another instance has
 534          * timestamp within receive.certnonceslop seconds, we pretend
 535          * as if we issued that nonce when reporting to the hook.
 536          */
 537
 538         /* nonce is concat(<seconds-since-epoch>, "-", <hmac>) */
 539         if (*nonce <= '0' || '9' < *nonce) {
 540                 retval = NONCE_BAD;
 541                 goto leave;
 542         }
 543         stamp = parse_timestamp(nonce, &bohmac, 10);
 544         if (bohmac == nonce || bohmac[0] != '-') {
 545                 retval = NONCE_BAD;
 546                 goto leave;
 547         }
 548
 549         expect = prepare_push_cert_nonce(service_dir, stamp);
 550         if (strcmp(expect, nonce)) {
 551                 /* Not what we would have signed earlier */
 552                 retval = NONCE_BAD;
 553                 goto leave;
 554         }
 555
 556         /*
 557          * By how many seconds is this nonce stale?  Negative value
 558          * would mean it was issued by another server with its clock
 559          * skewed in the future.
 560          */
 561         ostamp = parse_timestamp(push_cert_nonce, NULL, 10);
 562         nonce_stamp_slop = (long)ostamp - (long)stamp;
 563
 564         if (nonce_stamp_slop_limit &&
 565             labs(nonce_stamp_slop) <= nonce_stamp_slop_limit) {
 566                 /*
 567                  * Pretend as if the received nonce (which passes the
 568                  * HMAC check, so it is not a forged by third-party)
 569                  * is what we issued.
 570                  */
 571                 free((void *)push_cert_nonce);
 572                 push_cert_nonce = xstrdup(nonce);
 573                 retval = NONCE_OK;
 574         } else {
 575                 retval = NONCE_SLOP;
 576         }
 577
 578 leave:
 579         free(nonce);
 580         free(expect);
 581         return retval;
 582 }
 583
 584 /*
 585  * Return 1 if there is no push_cert or if the push options in push_cert are
 586  * the same as those in the argument; 0 otherwise.
 587  */
 588 static int check_cert_push_options(const struct string_list *push_options)
 589 {
 590         const char *buf = push_cert.buf;
 591         int len = push_cert.len;
 592
 593         char *option;
 594         const char *next_line;
 595         int options_seen = 0;
 596
 597         int retval = 1;
 598
 599         if (!len)
 600                 return 1;
 601
 602         while ((option = find_header(buf, len, "push-option", &next_line))) {
 603                 len -= (next_line - buf);
 604                 buf = next_line;
 605                 options_seen++;
 606                 if (options_seen > push_options->nr
 607                     || strcmp(option,
 608                               push_options->items[options_seen - 1].string)) {
 609                         retval = 0;
 610                         goto leave;
 611                 }
 612                 free(option);
 613         }
 614
 615         if (options_seen != push_options->nr)
 616                 retval = 0;
 617
 618 leave:
 619         free(option);
 620         return retval;
 621 }
 622
 623 static void prepare_push_cert_sha1(struct child_process *proc)
 624 {
 625         static int already_done;
 626
 627         if (!push_cert.len)
 628                 return;
 629
 630         if (!already_done) {
 631                 struct strbuf gpg_output = STRBUF_INIT;
 632                 struct strbuf gpg_status = STRBUF_INIT;
 633                 int bogs /* beginning_of_gpg_sig */;
 634
 635                 already_done = 1;
 636                 if (write_sha1_file(push_cert.buf, push_cert.len, "blob", push_cert_sha1))
 637                         hashclr(push_cert_sha1);
 638
 639                 memset(&sigcheck, '\0', sizeof(sigcheck));
 640                 sigcheck.result = 'N';
 641
 642                 bogs = parse_signature(push_cert.buf, push_cert.len);
 643                 if (verify_signed_buffer(push_cert.buf, bogs,
 644                                          push_cert.buf + bogs, push_cert.len - bogs,
 645                                          &gpg_output, &gpg_status) < 0) {
 646                         ; /* error running gpg */
 647                 } else {
 648                         sigcheck.payload = push_cert.buf;
 649                         sigcheck.gpg_output = gpg_output.buf;
 650                         sigcheck.gpg_status = gpg_status.buf;
 651                         parse_gpg_output(&sigcheck);
 652                 }
 653
 654                 strbuf_release(&gpg_output);
 655                 strbuf_release(&gpg_status);
 656                 nonce_status = check_nonce(push_cert.buf, bogs);
 657         }
 658         if (!is_null_sha1(push_cert_sha1)) {
 659                 argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT=%s",
 660                                  sha1_to_hex(push_cert_sha1));
 661                 argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_SIGNER=%s",
 662                                  sigcheck.signer ? sigcheck.signer : "");
 663                 argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_KEY=%s",
 664                                  sigcheck.key ? sigcheck.key : "");
 665                 argv_array_pushf(&proc->env_array, "GIT_PUSH_CERT_STATUS=%c",
 666                                  sigcheck.result);
 667                 if (push_cert_nonce) {
 668                         argv_array_pushf(&proc->env_array,
 669                                          "GIT_PUSH_CERT_NONCE=%s",
 670                                          push_cert_nonce);
 671                         argv_array_pushf(&proc->env_array,
 672                                          "GIT_PUSH_CERT_NONCE_STATUS=%s",
 673                                          nonce_status);
 674                         if (nonce_status == NONCE_SLOP)
 675                                 argv_array_pushf(&proc->env_array,
 676                                                  "GIT_PUSH_CERT_NONCE_SLOP=%ld",
 677                                                  nonce_stamp_slop);
 678                 }
 679         }
 680 }
 681
 682 struct receive_hook_feed_state {
 683         struct command *cmd;
 684         int skip_broken;
 685         struct strbuf buf;
 686         const struct string_list *push_options;
 687 };
 688
 689 typedef int (*feed_fn)(void *, const char **, size_t *);
 690 static int run_and_feed_hook(const char *hook_name, feed_fn feed,
 691                              struct receive_hook_feed_state *feed_state)
 692 {
 693         struct child_process proc = CHILD_PROCESS_INIT;
 694         struct async muxer;
 695         const char *argv[2];
 696         int code;
 697
 698         argv[0] = find_hook(hook_name);
 699         if (!argv[0])
 700                 return 0;
 701
 702         argv[1] = NULL;
 703
 704         proc.argv = argv;
 705         proc.in = -1;
 706         proc.stdout_to_stderr = 1;
 707         if (feed_state->push_options) {
 708                 int i;
 709                 for (i = 0; i < feed_state->push_options->nr; i++)
 710                         argv_array_pushf(&proc.env_array,
 711                                 "GIT_PUSH_OPTION_%d=%s", i,
 712                                 feed_state->push_options->items[i].string);
 713                 argv_array_pushf(&proc.env_array, "GIT_PUSH_OPTION_COUNT=%d",
 714                                  feed_state->push_options->nr);
 715         } else
 716                 argv_array_pushf(&proc.env_array, "GIT_PUSH_OPTION_COUNT");
 717
 718         if (tmp_objdir)
 719                 argv_array_pushv(&proc.env_array, tmp_objdir_env(tmp_objdir));
 720
 721         if (use_sideband) {
 722                 memset(&muxer, 0, sizeof(muxer));
 723                 muxer.proc = copy_to_sideband;
 724                 muxer.in = -1;
 725                 code = start_async(&muxer);
 726                 if (code)
 727                         return code;
 728                 proc.err = muxer.in;
 729         }
 730
 731         prepare_push_cert_sha1(&proc);
 732
 733         code = start_command(&proc);
 734         if (code) {
 735                 if (use_sideband)
 736                         finish_async(&muxer);
 737                 return code;
 738         }
 739
 740         sigchain_push(SIGPIPE, SIG_IGN);
 741
 742         while (1) {
 743                 const char *buf;
 744                 size_t n;
 745                 if (feed(feed_state, &buf, &n))
 746                         break;
 747                 if (write_in_full(proc.in, buf, n) < 0)
 748                         break;
 749         }
 750         close(proc.in);
 751         if (use_sideband)
 752                 finish_async(&muxer);
 753
 754         sigchain_pop(SIGPIPE);
 755
 756         return finish_command(&proc);
 757 }
 758
 759 static int feed_receive_hook(void *state_, const char **bufp, size_t *sizep)
 760 {
 761         struct receive_hook_feed_state *state = state_;
 762         struct command *cmd = state->cmd;
 763
 764         while (cmd &&
 765                state->skip_broken && (cmd->error_string || cmd->did_not_exist))
 766                 cmd = cmd->next;
 767         if (!cmd)
 768                 return -1; /* EOF */
 769         strbuf_reset(&state->buf);
 770         strbuf_addf(&state->buf, "%s %s %s\n",
 771                     oid_to_hex(&cmd->old_oid), oid_to_hex(&cmd->new_oid),
 772                     cmd->ref_name);
 773         state->cmd = cmd->next;
 774         if (bufp) {
 775                 *bufp = state->buf.buf;
 776                 *sizep = state->buf.len;
 777         }
 778         return 0;
 779 }
 780
 781 static int run_receive_hook(struct command *commands,
 782                             const char *hook_name,
 783                             int skip_broken,
 784                             const struct string_list *push_options)
 785 {
 786         struct receive_hook_feed_state state;
 787         int status;
 788
 789         strbuf_init(&state.buf, 0);
 790         state.cmd = commands;
 791         state.skip_broken = skip_broken;
 792         if (feed_receive_hook(&state, NULL, NULL))
 793                 return 0;
 794         state.cmd = commands;
 795         state.push_options = push_options;
 796         status = run_and_feed_hook(hook_name, feed_receive_hook, &state);
 797         strbuf_release(&state.buf);
 798         return status;
 799 }
 800
 801 static int run_update_hook(struct command *cmd)
 802 {
 803         const char *argv[5];
 804         struct child_process proc = CHILD_PROCESS_INIT;
 805         int code;
 806
 807         argv[0] = find_hook("update");
 808         if (!argv[0])
 809                 return 0;
 810
 811         argv[1] = cmd->ref_name;
 812         argv[2] = oid_to_hex(&cmd->old_oid);
 813         argv[3] = oid_to_hex(&cmd->new_oid);
 814         argv[4] = NULL;
 815
 816         proc.no_stdin = 1;
 817         proc.stdout_to_stderr = 1;
 818         proc.err = use_sideband ? -1 : 0;
 819         proc.argv = argv;
 820
 821         code = start_command(&proc);
 822         if (code)
 823                 return code;
 824         if (use_sideband)
 825                 copy_to_sideband(proc.err, -1, NULL);
 826         return finish_command(&proc);
 827 }
 828
 829 static int is_ref_checked_out(const char *ref)
 830 {
 831         if (is_bare_repository())
 832                 return 0;
 833
 834         if (!head_name)
 835                 return 0;
 836         return !strcmp(head_name, ref);
 837 }
 838
 839 static char *refuse_unconfigured_deny_msg =
 840         N_("By default, updating the current branch in a non-bare repository\n"
 841            "is denied, because it will make the index and work tree inconsistent\n"
 842            "with what you pushed, and will require 'git reset --hard' to match\n"
 843            "the work tree to HEAD.\n"
 844            "\n"
 845            "You can set the 'receive.denyCurrentBranch' configuration variable\n"
 846            "to 'ignore' or 'warn' in the remote repository to allow pushing into\n"
 847            "its current branch; however, this is not recommended unless you\n"
 848            "arranged to update its work tree to match what you pushed in some\n"
 849            "other way.\n"
 850            "\n"
 851            "To squelch this message and still keep the default behaviour, set\n"
 852            "'receive.denyCurrentBranch' configuration variable to 'refuse'.");
 853
 854 static void refuse_unconfigured_deny(void)
 855 {
 856         rp_error("%s", _(refuse_unconfigured_deny_msg));
 857 }
 858
 859 static char *refuse_unconfigured_deny_delete_current_msg =
 860         N_("By default, deleting the current branch is denied, because the next\n"
 861            "'git clone' won't result in any file checked out, causing confusion.\n"
 862            "\n"
 863            "You can set 'receive.denyDeleteCurrent' configuration variable to\n"
 864            "'warn' or 'ignore' in the remote repository to allow deleting the\n"
 865            "current branch, with or without a warning message.\n"
 866            "\n"
 867            "To squelch this message, you can set it to 'refuse'.");
 868
 869 static void refuse_unconfigured_deny_delete_current(void)
 870 {
 871         rp_error("%s", _(refuse_unconfigured_deny_delete_current_msg));
 872 }
 873
 874 static int command_singleton_iterator(void *cb_data, unsigned char sha1[20]);
 875 static int update_shallow_ref(struct command *cmd, struct shallow_info *si)
 876 {
 877         static struct lock_file shallow_lock;
 878         struct oid_array extra = OID_ARRAY_INIT;
 879         struct check_connected_options opt = CHECK_CONNECTED_INIT;
 880         uint32_t mask = 1 << (cmd->index % 32);
 881         int i;
 882
 883         trace_printf_key(&trace_shallow,
 884                          "shallow: update_shallow_ref %s\n", cmd->ref_name);
 885         for (i = 0; i < si->shallow->nr; i++)
 886                 if (si->used_shallow[i] &&
 887                     (si->used_shallow[i][cmd->index / 32] & mask) &&
 888                     !delayed_reachability_test(si, i))
 889                         oid_array_append(&extra, &si->shallow->oid[i]);
 890
 891         opt.env = tmp_objdir_env(tmp_objdir);
 892         setup_alternate_shallow(&shallow_lock, &opt.shallow_file, &extra);
 893         if (check_connected(command_singleton_iterator, cmd, &opt)) {
 894                 rollback_lock_file(&shallow_lock);
 895                 oid_array_clear(&extra);
 896                 return -1;
 897         }
 898
 899         commit_lock_file(&shallow_lock);
 900
 901         /*
 902          * Make sure setup_alternate_shallow() for the next ref does
 903          * not lose these new roots..
 904          */
 905         for (i = 0; i < extra.nr; i++)
 906                 register_shallow(&extra.oid[i]);
 907
 908         si->shallow_ref[cmd->index] = 0;
 909         oid_array_clear(&extra);
 910         return 0;
 911 }
 912
 913 /*
 914  * NEEDSWORK: we should consolidate various implementions of "are we
 915  * on an unborn branch?" test into one, and make the unified one more
 916  * robust. !get_sha1() based check used here and elsewhere would not
 917  * allow us to tell an unborn branch from corrupt ref, for example.
 918  * For the purpose of fixing "deploy-to-update does not work when
 919  * pushing into an empty repository" issue, this should suffice for
 920  * now.
 921  */
 922 static int head_has_history(void)
 923 {
 924         struct object_id oid;
 925
 926         return !get_oid("HEAD", &oid);
 927 }
 928
 929 static const char *push_to_deploy(unsigned char *sha1,
 930                                   struct argv_array *env,
 931                                   const char *work_tree)
 932 {
 933         const char *update_refresh[] = {
 934                 "update-index", "-q", "--ignore-submodules", "--refresh", NULL
 935         };
 936         const char *diff_files[] = {
 937                 "diff-files", "--quiet", "--ignore-submodules", "--", NULL
 938         };
 939         const char *diff_index[] = {
 940                 "diff-index", "--quiet", "--cached", "--ignore-submodules",
 941                 NULL, "--", NULL
 942         };
 943         const char *read_tree[] = {
 944                 "read-tree", "-u", "-m", NULL, NULL
 945         };
 946         struct child_process child = CHILD_PROCESS_INIT;
 947
 948         child.argv = update_refresh;
 949         child.env = env->argv;
 950         child.dir = work_tree;
 951         child.no_stdin = 1;
 952         child.stdout_to_stderr = 1;
 953         child.git_cmd = 1;
 954         if (run_command(&child))
 955                 return "Up-to-date check failed";
 956
 957         /* run_command() does not clean up completely; reinitialize */
 958         child_process_init(&child);
 959         child.argv = diff_files;
 960         child.env = env->argv;
 961         child.dir = work_tree;
 962         child.no_stdin = 1;
 963         child.stdout_to_stderr = 1;
 964         child.git_cmd = 1;
 965         if (run_command(&child))
 966                 return "Working directory has unstaged changes";
 967
 968         /* diff-index with either HEAD or an empty tree */
 969         diff_index[4] = head_has_history() ? "HEAD" : EMPTY_TREE_SHA1_HEX;
 970
 971         child_process_init(&child);
 972         child.argv = diff_index;
 973         child.env = env->argv;
 974         child.no_stdin = 1;
 975         child.no_stdout = 1;
 976         child.stdout_to_stderr = 0;
 977         child.git_cmd = 1;
 978         if (run_command(&child))
 979                 return "Working directory has staged changes";
 980
 981         read_tree[3] = sha1_to_hex(sha1);
 982         child_process_init(&child);
 983         child.argv = read_tree;
 984         child.env = env->argv;
 985         child.dir = work_tree;
 986         child.no_stdin = 1;
 987         child.no_stdout = 1;
 988         child.stdout_to_stderr = 0;
 989         child.git_cmd = 1;
 990         if (run_command(&child))
 991                 return "Could not update working tree to new HEAD";
 992
 993         return NULL;
 994 }
 995
 996 static const char *push_to_checkout_hook = "push-to-checkout";
 997
 998 static const char *push_to_checkout(unsigned char *sha1,
 999                                     struct argv_array *env,
1000                                     const char *work_tree)
1001 {
1002         argv_array_pushf(env, "GIT_WORK_TREE=%s", absolute_path(work_tree));
1003         if (run_hook_le(env->argv, push_to_checkout_hook,
1004                         sha1_to_hex(sha1), NULL))
1005                 return "push-to-checkout hook declined";
1006         else
1007                 return NULL;
1008 }
1009
1010 static const char *update_worktree(unsigned char *sha1)
1011 {
1012         const char *retval;
1013         const char *work_tree = git_work_tree_cfg ? git_work_tree_cfg : "..";
1014         struct argv_array env = ARGV_ARRAY_INIT;
1015
1016         if (is_bare_repository())
1017                 return "denyCurrentBranch = updateInstead needs a worktree";
1018
1019         argv_array_pushf(&env, "GIT_DIR=%s", absolute_path(get_git_dir()));
1020
1021         if (!find_hook(push_to_checkout_hook))
1022                 retval = push_to_deploy(sha1, &env, work_tree);
1023         else
1024                 retval = push_to_checkout(sha1, &env, work_tree);
1025
1026         argv_array_clear(&env);
1027         return retval;
1028 }
1029
1030 static const char *update(struct command *cmd, struct shallow_info *si)
1031 {
1032         const char *name = cmd->ref_name;
1033         struct strbuf namespaced_name_buf = STRBUF_INIT;
1034         static char *namespaced_name;
1035         const char *ret;
1036         struct object_id *old_oid = &cmd->old_oid;
1037         struct object_id *new_oid = &cmd->new_oid;
1038
1039         /* only refs/... are allowed */
1040         if (!starts_with(name, "refs/") || check_refname_format(name + 5, 0)) {
1041                 rp_error("refusing to create funny ref '%s' remotely", name);
1042                 return "funny refname";
1043         }
1044
1045         strbuf_addf(&namespaced_name_buf, "%s%s", get_git_namespace(), name);
1046         free(namespaced_name);
1047         namespaced_name = strbuf_detach(&namespaced_name_buf, NULL);
1048
1049         if (is_ref_checked_out(namespaced_name)) {
1050                 switch (deny_current_branch) {
1051                 case DENY_IGNORE:
1052                         break;
1053                 case DENY_WARN:
1054                         rp_warning("updating the current branch");
1055                         break;
1056                 case DENY_REFUSE:
1057                 case DENY_UNCONFIGURED:
1058                         rp_error("refusing to update checked out branch: %s", name);
1059                         if (deny_current_branch == DENY_UNCONFIGURED)
1060                                 refuse_unconfigured_deny();
1061                         return "branch is currently checked out";
1062                 case DENY_UPDATE_INSTEAD:
1063                         ret = update_worktree(new_oid->hash);
1064                         if (ret)
1065                                 return ret;
1066                         break;
1067                 }
1068         }
1069
1070         if (!is_null_oid(new_oid) && !has_object_file(new_oid)) {
1071                 error("unpack should have generated %s, "
1072                       "but I can't find it!", oid_to_hex(new_oid));
1073                 return "bad pack";
1074         }
1075
1076         if (!is_null_oid(old_oid) && is_null_oid(new_oid)) {
1077                 if (deny_deletes && starts_with(name, "refs/heads/")) {
1078                         rp_error("denying ref deletion for %s", name);
1079                         return "deletion prohibited";
1080                 }
1081
1082                 if (head_name && !strcmp(namespaced_name, head_name)) {
1083                         switch (deny_delete_current) {
1084                         case DENY_IGNORE:
1085                                 break;
1086                         case DENY_WARN:
1087                                 rp_warning("deleting the current branch");
1088                                 break;
1089                         case DENY_REFUSE:
1090                         case DENY_UNCONFIGURED:
1091                         case DENY_UPDATE_INSTEAD:
1092                                 if (deny_delete_current == DENY_UNCONFIGURED)
1093                                         refuse_unconfigured_deny_delete_current();
1094                                 rp_error("refusing to delete the current branch: %s", name);
1095                                 return "deletion of the current branch prohibited";
1096                         default:
1097                                 return "Invalid denyDeleteCurrent setting";
1098                         }
1099                 }
1100         }
1101
1102         if (deny_non_fast_forwards && !is_null_oid(new_oid) &&
1103             !is_null_oid(old_oid) &&
1104             starts_with(name, "refs/heads/")) {
1105                 struct object *old_object, *new_object;
1106                 struct commit *old_commit, *new_commit;
1107
1108                 old_object = parse_object(old_oid);
1109                 new_object = parse_object(new_oid);
1110
1111                 if (!old_object || !new_object ||
1112                     old_object->type != OBJ_COMMIT ||
1113                     new_object->type != OBJ_COMMIT) {
1114                         error("bad sha1 objects for %s", name);
1115                         return "bad ref";
1116                 }
1117                 old_commit = (struct commit *)old_object;
1118                 new_commit = (struct commit *)new_object;
1119                 if (!in_merge_bases(old_commit, new_commit)) {
1120                         rp_error("denying non-fast-forward %s"
1121                                  " (you should pull first)", name);
1122                         return "non-fast-forward";
1123                 }
1124         }
1125         if (run_update_hook(cmd)) {
1126                 rp_error("hook declined to update %s", name);
1127                 return "hook declined";
1128         }
1129
1130         if (is_null_oid(new_oid)) {
1131                 struct strbuf err = STRBUF_INIT;
1132                 if (!parse_object(old_oid)) {
1133                         old_oid = NULL;
1134                         if (ref_exists(name)) {
1135                                 rp_warning("Allowing deletion of corrupt ref.");
1136                         } else {
1137                                 rp_warning("Deleting a non-existent ref.");
1138                                 cmd->did_not_exist = 1;
1139                         }
1140                 }
1141                 if (ref_transaction_delete(transaction,
1142                                            namespaced_name,
1143                                            old_oid ? old_oid->hash : NULL,
1144                                            0, "push", &err)) {
1145                         rp_error("%s", err.buf);
1146                         strbuf_release(&err);
1147                         return "failed to delete";
1148                 }
1149                 strbuf_release(&err);
1150                 return NULL; /* good */
1151         }
1152         else {
1153                 struct strbuf err = STRBUF_INIT;
1154                 if (shallow_update && si->shallow_ref[cmd->index] &&
1155                     update_shallow_ref(cmd, si))
1156                         return "shallow error";
1157
1158                 if (ref_transaction_update(transaction,
1159                                            namespaced_name,
1160                                            new_oid->hash, old_oid->hash,
1161                                            0, "push",
1162                                            &err)) {
1163                         rp_error("%s", err.buf);
1164                         strbuf_release(&err);
1165
1166                         return "failed to update ref";
1167                 }
1168                 strbuf_release(&err);
1169
1170                 return NULL; /* good */
1171         }
1172 }
1173
1174 static void run_update_post_hook(struct command *commands)
1175 {
1176         struct command *cmd;
1177         struct child_process proc = CHILD_PROCESS_INIT;
1178         const char *hook;
1179
1180         hook = find_hook("post-update");
1181         if (!hook)
1182                 return;
1183
1184         for (cmd = commands; cmd; cmd = cmd->next) {
1185                 if (cmd->error_string || cmd->did_not_exist)
1186                         continue;
1187                 if (!proc.args.argc)
1188                         argv_array_push(&proc.args, hook);
1189                 argv_array_push(&proc.args, cmd->ref_name);
1190         }
1191         if (!proc.args.argc)
1192                 return;
1193
1194         proc.no_stdin = 1;
1195         proc.stdout_to_stderr = 1;
1196         proc.err = use_sideband ? -1 : 0;
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(struct command *cmd, struct string_list *list)
1206 {
1207         struct strbuf buf = STRBUF_INIT;
1208         const char *dst_name;
1209         struct string_list_item *item;
1210         struct command *dst_cmd;
1211         unsigned char sha1[GIT_MAX_RAWSZ];
1212         int flag;
1213
1214         strbuf_addf(&buf, "%s%s", get_git_namespace(), cmd->ref_name);
1215         dst_name = resolve_ref_unsafe(buf.buf, 0, sha1, &flag);
1216         strbuf_release(&buf);
1217
1218         if (!(flag & REF_ISSYMREF))
1219                 return;
1220
1221         if (!dst_name) {
1222                 rp_error("refusing update to broken symref '%s'", cmd->ref_name);
1223                 cmd->skip_update = 1;
1224                 cmd->error_string = "broken symref";
1225                 return;
1226         }
1227         dst_name = strip_namespace(dst_name);
1228
1229         if ((item = string_list_lookup(list, dst_name)) == NULL)
1230                 return;
1231
1232         cmd->skip_update = 1;
1233
1234         dst_cmd = (struct command *) item->util;
1235
1236         if (!oidcmp(&cmd->old_oid, &dst_cmd->old_oid) &&
1237             !oidcmp(&cmd->new_oid, &dst_cmd->new_oid))
1238                 return;
1239
1240         dst_cmd->skip_update = 1;
1241
1242         rp_error("refusing inconsistent update between symref '%s' (%s..%s) and"
1243                  " its target '%s' (%s..%s)",
1244                  cmd->ref_name,
1245                  find_unique_abbrev(cmd->old_oid.hash, DEFAULT_ABBREV),
1246                  find_unique_abbrev(cmd->new_oid.hash, DEFAULT_ABBREV),
1247                  dst_cmd->ref_name,
1248                  find_unique_abbrev(dst_cmd->old_oid.hash, DEFAULT_ABBREV),
1249                  find_unique_abbrev(dst_cmd->new_oid.hash, DEFAULT_ABBREV));
1250
1251         cmd->error_string = dst_cmd->error_string =
1252                 "inconsistent aliased update";
1253 }
1254
1255 static void check_aliased_updates(struct command *commands)
1256 {
1257         struct command *cmd;
1258         struct string_list ref_list = STRING_LIST_INIT_NODUP;
1259
1260         for (cmd = commands; cmd; cmd = cmd->next) {
1261                 struct string_list_item *item =
1262                         string_list_append(&ref_list, cmd->ref_name);
1263                 item->util = (void *)cmd;
1264         }
1265         string_list_sort(&ref_list);
1266
1267         for (cmd = commands; cmd; cmd = cmd->next) {
1268                 if (!cmd->error_string)
1269                         check_aliased_update(cmd, &ref_list);
1270         }
1271
1272         string_list_clear(&ref_list, 0);
1273 }
1274
1275 static int command_singleton_iterator(void *cb_data, unsigned char sha1[20])
1276 {
1277         struct command **cmd_list = cb_data;
1278         struct command *cmd = *cmd_list;
1279
1280         if (!cmd || is_null_oid(&cmd->new_oid))
1281                 return -1; /* end of list */
1282         *cmd_list = NULL; /* this returns only one */
1283         hashcpy(sha1, cmd->new_oid.hash);
1284         return 0;
1285 }
1286
1287 static void set_connectivity_errors(struct command *commands,
1288                                     struct shallow_info *si)
1289 {
1290         struct command *cmd;
1291
1292         for (cmd = commands; cmd; cmd = cmd->next) {
1293                 struct command *singleton = cmd;
1294                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
1295
1296                 if (shallow_update && si->shallow_ref[cmd->index])
1297                         /* to be checked in update_shallow_ref() */
1298                         continue;
1299
1300                 opt.env = tmp_objdir_env(tmp_objdir);
1301                 if (!check_connected(command_singleton_iterator, &singleton,
1302                                      &opt))
1303                         continue;
1304
1305                 cmd->error_string = "missing necessary objects";
1306         }
1307 }
1308
1309 struct iterate_data {
1310         struct command *cmds;
1311         struct shallow_info *si;
1312 };
1313
1314 static int iterate_receive_command_list(void *cb_data, unsigned char sha1[20])
1315 {
1316         struct iterate_data *data = cb_data;
1317         struct command **cmd_list = &data->cmds;
1318         struct command *cmd = *cmd_list;
1319
1320         for (; cmd; cmd = cmd->next) {
1321                 if (shallow_update && data->si->shallow_ref[cmd->index])
1322                         /* to be checked in update_shallow_ref() */
1323                         continue;
1324                 if (!is_null_oid(&cmd->new_oid) && !cmd->skip_update) {
1325                         hashcpy(sha1, cmd->new_oid.hash);
1326                         *cmd_list = cmd->next;
1327                         return 0;
1328                 }
1329         }
1330         *cmd_list = NULL;
1331         return -1; /* end of list */
1332 }
1333
1334 static void reject_updates_to_hidden(struct command *commands)
1335 {
1336         struct strbuf refname_full = STRBUF_INIT;
1337         size_t prefix_len;
1338         struct command *cmd;
1339
1340         strbuf_addstr(&refname_full, get_git_namespace());
1341         prefix_len = refname_full.len;
1342
1343         for (cmd = commands; cmd; cmd = cmd->next) {
1344                 if (cmd->error_string)
1345                         continue;
1346
1347                 strbuf_setlen(&refname_full, prefix_len);
1348                 strbuf_addstr(&refname_full, cmd->ref_name);
1349
1350                 if (!ref_is_hidden(cmd->ref_name, refname_full.buf))
1351                         continue;
1352                 if (is_null_oid(&cmd->new_oid))
1353                         cmd->error_string = "deny deleting a hidden ref";
1354                 else
1355                         cmd->error_string = "deny updating a hidden ref";
1356         }
1357
1358         strbuf_release(&refname_full);
1359 }
1360
1361 static int should_process_cmd(struct command *cmd)
1362 {
1363         return !cmd->error_string && !cmd->skip_update;
1364 }
1365
1366 static void warn_if_skipped_connectivity_check(struct command *commands,
1367                                                struct shallow_info *si)
1368 {
1369         struct command *cmd;
1370         int checked_connectivity = 1;
1371
1372         for (cmd = commands; cmd; cmd = cmd->next) {
1373                 if (should_process_cmd(cmd) && si->shallow_ref[cmd->index]) {
1374                         error("BUG: connectivity check has not been run on ref %s",
1375                               cmd->ref_name);
1376                         checked_connectivity = 0;
1377                 }
1378         }
1379         if (!checked_connectivity)
1380                 die("BUG: connectivity check skipped???");
1381 }
1382
1383 static void execute_commands_non_atomic(struct command *commands,
1384                                         struct shallow_info *si)
1385 {
1386         struct command *cmd;
1387         struct strbuf err = STRBUF_INIT;
1388
1389         for (cmd = commands; cmd; cmd = cmd->next) {
1390                 if (!should_process_cmd(cmd))
1391                         continue;
1392
1393                 transaction = ref_transaction_begin(&err);
1394                 if (!transaction) {
1395                         rp_error("%s", err.buf);
1396                         strbuf_reset(&err);
1397                         cmd->error_string = "transaction failed to start";
1398                         continue;
1399                 }
1400
1401                 cmd->error_string = update(cmd, si);
1402
1403                 if (!cmd->error_string
1404                     && ref_transaction_commit(transaction, &err)) {
1405                         rp_error("%s", err.buf);
1406                         strbuf_reset(&err);
1407                         cmd->error_string = "failed to update ref";
1408                 }
1409                 ref_transaction_free(transaction);
1410         }
1411         strbuf_release(&err);
1412 }
1413
1414 static void execute_commands_atomic(struct command *commands,
1415                                         struct shallow_info *si)
1416 {
1417         struct command *cmd;
1418         struct strbuf err = STRBUF_INIT;
1419         const char *reported_error = "atomic push failure";
1420
1421         transaction = ref_transaction_begin(&err);
1422         if (!transaction) {
1423                 rp_error("%s", err.buf);
1424                 strbuf_reset(&err);
1425                 reported_error = "transaction failed to start";
1426                 goto failure;
1427         }
1428
1429         for (cmd = commands; cmd; cmd = cmd->next) {
1430                 if (!should_process_cmd(cmd))
1431                         continue;
1432
1433                 cmd->error_string = update(cmd, si);
1434
1435                 if (cmd->error_string)
1436                         goto failure;
1437         }
1438
1439         if (ref_transaction_commit(transaction, &err)) {
1440                 rp_error("%s", err.buf);
1441                 reported_error = "atomic transaction failed";
1442                 goto failure;
1443         }
1444         goto cleanup;
1445
1446 failure:
1447         for (cmd = commands; cmd; cmd = cmd->next)
1448                 if (!cmd->error_string)
1449                         cmd->error_string = reported_error;
1450
1451 cleanup:
1452         ref_transaction_free(transaction);
1453         strbuf_release(&err);
1454 }
1455
1456 static void execute_commands(struct command *commands,
1457                              const char *unpacker_error,
1458                              struct shallow_info *si,
1459                              const struct string_list *push_options)
1460 {
1461         struct check_connected_options opt = CHECK_CONNECTED_INIT;
1462         struct command *cmd;
1463         struct object_id oid;
1464         struct iterate_data data;
1465         struct async muxer;
1466         int err_fd = 0;
1467
1468         if (unpacker_error) {
1469                 for (cmd = commands; cmd; cmd = cmd->next)
1470                         cmd->error_string = "unpacker error";
1471                 return;
1472         }
1473
1474         if (use_sideband) {
1475                 memset(&muxer, 0, sizeof(muxer));
1476                 muxer.proc = copy_to_sideband;
1477                 muxer.in = -1;
1478                 if (!start_async(&muxer))
1479                         err_fd = muxer.in;
1480                 /* ...else, continue without relaying sideband */
1481         }
1482
1483         data.cmds = commands;
1484         data.si = si;
1485         opt.err_fd = err_fd;
1486         opt.progress = err_fd && !quiet;
1487         opt.env = tmp_objdir_env(tmp_objdir);
1488         if (check_connected(iterate_receive_command_list, &data, &opt))
1489                 set_connectivity_errors(commands, si);
1490
1491         if (use_sideband)
1492                 finish_async(&muxer);
1493
1494         reject_updates_to_hidden(commands);
1495
1496         if (run_receive_hook(commands, "pre-receive", 0, push_options)) {
1497                 for (cmd = commands; cmd; cmd = cmd->next) {
1498                         if (!cmd->error_string)
1499                                 cmd->error_string = "pre-receive hook declined";
1500                 }
1501                 return;
1502         }
1503
1504         /*
1505          * Now we'll start writing out refs, which means the objects need
1506          * to be in their final positions so that other processes can see them.
1507          */
1508         if (tmp_objdir_migrate(tmp_objdir) < 0) {
1509                 for (cmd = commands; cmd; cmd = cmd->next) {
1510                         if (!cmd->error_string)
1511                                 cmd->error_string = "unable to migrate objects to permanent storage";
1512                 }
1513                 return;
1514         }
1515         tmp_objdir = NULL;
1516
1517         check_aliased_updates(commands);
1518
1519         free(head_name_to_free);
1520         head_name = head_name_to_free = resolve_refdup("HEAD", 0, oid.hash, NULL);
1521
1522         if (use_atomic)
1523                 execute_commands_atomic(commands, si);
1524         else
1525                 execute_commands_non_atomic(commands, si);
1526
1527         if (shallow_update)
1528                 warn_if_skipped_connectivity_check(commands, si);
1529 }
1530
1531 static struct command **queue_command(struct command **tail,
1532                                       const char *line,
1533                                       int linelen)
1534 {
1535         struct object_id old_oid, new_oid;
1536         struct command *cmd;
1537         const char *refname;
1538         int reflen;
1539         const char *p;
1540
1541         if (parse_oid_hex(line, &old_oid, &p) ||
1542             *p++ != ' ' ||
1543             parse_oid_hex(p, &new_oid, &p) ||
1544             *p++ != ' ')
1545                 die("protocol error: expected old/new/ref, got '%s'", line);
1546
1547         refname = p;
1548         reflen = linelen - (p - line);
1549         FLEX_ALLOC_MEM(cmd, ref_name, refname, reflen);
1550         oidcpy(&cmd->old_oid, &old_oid);
1551         oidcpy(&cmd->new_oid, &new_oid);
1552         *tail = cmd;
1553         return &cmd->next;
1554 }
1555
1556 static void queue_commands_from_cert(struct command **tail,
1557                                      struct strbuf *push_cert)
1558 {
1559         const char *boc, *eoc;
1560
1561         if (*tail)
1562                 die("protocol error: got both push certificate and unsigned commands");
1563
1564         boc = strstr(push_cert->buf, "\n\n");
1565         if (!boc)
1566                 die("malformed push certificate %.*s", 100, push_cert->buf);
1567         else
1568                 boc += 2;
1569         eoc = push_cert->buf + parse_signature(push_cert->buf, push_cert->len);
1570
1571         while (boc < eoc) {
1572                 const char *eol = memchr(boc, '\n', eoc - boc);
1573                 tail = queue_command(tail, boc, eol ? eol - boc : eoc - boc);
1574                 boc = eol ? eol + 1 : eoc;
1575         }
1576 }
1577
1578 static struct command *read_head_info(struct oid_array *shallow)
1579 {
1580         struct command *commands = NULL;
1581         struct command **p = &commands;
1582         for (;;) {
1583                 char *line;
1584                 int len, linelen;
1585
1586                 line = packet_read_line(0, &len);
1587                 if (!line)
1588                         break;
1589
1590                 if (len > 8 && starts_with(line, "shallow ")) {
1591                         struct object_id oid;
1592                         if (get_oid_hex(line + 8, &oid))
1593                                 die("protocol error: expected shallow sha, got '%s'",
1594                                     line + 8);
1595                         oid_array_append(shallow, &oid);
1596                         continue;
1597                 }
1598
1599                 linelen = strlen(line);
1600                 if (linelen < len) {
1601                         const char *feature_list = line + linelen + 1;
1602                         if (parse_feature_request(feature_list, "report-status"))
1603                                 report_status = 1;
1604                         if (parse_feature_request(feature_list, "side-band-64k"))
1605                                 use_sideband = LARGE_PACKET_MAX;
1606                         if (parse_feature_request(feature_list, "quiet"))
1607                                 quiet = 1;
1608                         if (advertise_atomic_push
1609                             && parse_feature_request(feature_list, "atomic"))
1610                                 use_atomic = 1;
1611                         if (advertise_push_options
1612                             && parse_feature_request(feature_list, "push-options"))
1613                                 use_push_options = 1;
1614                 }
1615
1616                 if (!strcmp(line, "push-cert")) {
1617                         int true_flush = 0;
1618                         char certbuf[1024];
1619
1620                         for (;;) {
1621                                 len = packet_read(0, NULL, NULL,
1622                                                   certbuf, sizeof(certbuf), 0);
1623                                 if (!len) {
1624                                         true_flush = 1;
1625                                         break;
1626                                 }
1627                                 if (!strcmp(certbuf, "push-cert-end\n"))
1628                                         break; /* end of cert */
1629                                 strbuf_addstr(&push_cert, certbuf);
1630                         }
1631
1632                         if (true_flush)
1633                                 break;
1634                         continue;
1635                 }
1636
1637                 p = queue_command(p, line, linelen);
1638         }
1639
1640         if (push_cert.len)
1641                 queue_commands_from_cert(p, &push_cert);
1642
1643         return commands;
1644 }
1645
1646 static void read_push_options(struct string_list *options)
1647 {
1648         while (1) {
1649                 char *line;
1650                 int len;
1651
1652                 line = packet_read_line(0, &len);
1653
1654                 if (!line)
1655                         break;
1656
1657                 string_list_append(options, line);
1658         }
1659 }
1660
1661 static const char *parse_pack_header(struct pack_header *hdr)
1662 {
1663         switch (read_pack_header(0, hdr)) {
1664         case PH_ERROR_EOF:
1665                 return "eof before pack header was fully read";
1666
1667         case PH_ERROR_PACK_SIGNATURE:
1668                 return "protocol error (pack signature mismatch detected)";
1669
1670         case PH_ERROR_PROTOCOL:
1671                 return "protocol error (pack version unsupported)";
1672
1673         default:
1674                 return "unknown error in parse_pack_header";
1675
1676         case 0:
1677                 return NULL;
1678         }
1679 }
1680
1681 static const char *pack_lockfile;
1682
1683 static void push_header_arg(struct argv_array *args, struct pack_header *hdr)
1684 {
1685         argv_array_pushf(args, "--pack_header=%"PRIu32",%"PRIu32,
1686                         ntohl(hdr->hdr_version), ntohl(hdr->hdr_entries));
1687 }
1688
1689 static const char *unpack(int err_fd, struct shallow_info *si)
1690 {
1691         struct pack_header hdr;
1692         const char *hdr_err;
1693         int status;
1694         struct child_process child = CHILD_PROCESS_INIT;
1695         int fsck_objects = (receive_fsck_objects >= 0
1696                             ? receive_fsck_objects
1697                             : transfer_fsck_objects >= 0
1698                             ? transfer_fsck_objects
1699                             : 0);
1700
1701         hdr_err = parse_pack_header(&hdr);
1702         if (hdr_err) {
1703                 if (err_fd > 0)
1704                         close(err_fd);
1705                 return hdr_err;
1706         }
1707
1708         if (si->nr_ours || si->nr_theirs) {
1709                 alt_shallow_file = setup_temporary_shallow(si->shallow);
1710                 argv_array_push(&child.args, "--shallow-file");
1711                 argv_array_push(&child.args, alt_shallow_file);
1712         }
1713
1714         tmp_objdir = tmp_objdir_create();
1715         if (!tmp_objdir) {
1716                 if (err_fd > 0)
1717                         close(err_fd);
1718                 return "unable to create temporary object directory";
1719         }
1720         child.env = tmp_objdir_env(tmp_objdir);
1721
1722         /*
1723          * Normally we just pass the tmp_objdir environment to the child
1724          * processes that do the heavy lifting, but we may need to see these
1725          * objects ourselves to set up shallow information.
1726          */
1727         tmp_objdir_add_as_alternate(tmp_objdir);
1728
1729         if (ntohl(hdr.hdr_entries) < unpack_limit) {
1730                 argv_array_push(&child.args, "unpack-objects");
1731                 push_header_arg(&child.args, &hdr);
1732                 if (quiet)
1733                         argv_array_push(&child.args, "-q");
1734                 if (fsck_objects)
1735                         argv_array_pushf(&child.args, "--strict%s",
1736                                 fsck_msg_types.buf);
1737                 if (max_input_size)
1738                         argv_array_pushf(&child.args, "--max-input-size=%"PRIuMAX,
1739                                 (uintmax_t)max_input_size);
1740                 child.no_stdout = 1;
1741                 child.err = err_fd;
1742                 child.git_cmd = 1;
1743                 status = run_command(&child);
1744                 if (status)
1745                         return "unpack-objects abnormal exit";
1746         } else {
1747                 char hostname[HOST_NAME_MAX + 1];
1748
1749                 argv_array_pushl(&child.args, "index-pack", "--stdin", NULL);
1750                 push_header_arg(&child.args, &hdr);
1751
1752                 if (xgethostname(hostname, sizeof(hostname)))
1753                         xsnprintf(hostname, sizeof(hostname), "localhost");
1754                 argv_array_pushf(&child.args,
1755                                  "--keep=receive-pack %"PRIuMAX" on %s",
1756                                  (uintmax_t)getpid(),
1757                                  hostname);
1758
1759                 if (!quiet && err_fd)
1760                         argv_array_push(&child.args, "--show-resolving-progress");
1761                 if (use_sideband)
1762                         argv_array_push(&child.args, "--report-end-of-input");
1763                 if (fsck_objects)
1764                         argv_array_pushf(&child.args, "--strict%s",
1765                                 fsck_msg_types.buf);
1766                 if (!reject_thin)
1767                         argv_array_push(&child.args, "--fix-thin");
1768                 if (max_input_size)
1769                         argv_array_pushf(&child.args, "--max-input-size=%"PRIuMAX,
1770                                 (uintmax_t)max_input_size);
1771                 child.out = -1;
1772                 child.err = err_fd;
1773                 child.git_cmd = 1;
1774                 status = start_command(&child);
1775                 if (status)
1776                         return "index-pack fork failed";
1777                 pack_lockfile = index_pack_lockfile(child.out);
1778                 close(child.out);
1779                 status = finish_command(&child);
1780                 if (status)
1781                         return "index-pack abnormal exit";
1782                 reprepare_packed_git();
1783         }
1784         return NULL;
1785 }
1786
1787 static const char *unpack_with_sideband(struct shallow_info *si)
1788 {
1789         struct async muxer;
1790         const char *ret;
1791
1792         if (!use_sideband)
1793                 return unpack(0, si);
1794
1795         use_keepalive = KEEPALIVE_AFTER_NUL;
1796         memset(&muxer, 0, sizeof(muxer));
1797         muxer.proc = copy_to_sideband;
1798         muxer.in = -1;
1799         if (start_async(&muxer))
1800                 return NULL;
1801
1802         ret = unpack(muxer.in, si);
1803
1804         finish_async(&muxer);
1805         return ret;
1806 }
1807
1808 static void prepare_shallow_update(struct command *commands,
1809                                    struct shallow_info *si)
1810 {
1811         int i, j, k, bitmap_size = DIV_ROUND_UP(si->ref->nr, 32);
1812
1813         ALLOC_ARRAY(si->used_shallow, si->shallow->nr);
1814         assign_shallow_commits_to_refs(si, si->used_shallow, NULL);
1815
1816         si->need_reachability_test =
1817                 xcalloc(si->shallow->nr, sizeof(*si->need_reachability_test));
1818         si->reachable =
1819                 xcalloc(si->shallow->nr, sizeof(*si->reachable));
1820         si->shallow_ref = xcalloc(si->ref->nr, sizeof(*si->shallow_ref));
1821
1822         for (i = 0; i < si->nr_ours; i++)
1823                 si->need_reachability_test[si->ours[i]] = 1;
1824
1825         for (i = 0; i < si->shallow->nr; i++) {
1826                 if (!si->used_shallow[i])
1827                         continue;
1828                 for (j = 0; j < bitmap_size; j++) {
1829                         if (!si->used_shallow[i][j])
1830                                 continue;
1831                         si->need_reachability_test[i]++;
1832                         for (k = 0; k < 32; k++)
1833                                 if (si->used_shallow[i][j] & (1U << k))
1834                                         si->shallow_ref[j * 32 + k]++;
1835                 }
1836
1837                 /*
1838                  * true for those associated with some refs and belong
1839                  * in "ours" list aka "step 7 not done yet"
1840                  */
1841                 si->need_reachability_test[i] =
1842                         si->need_reachability_test[i] > 1;
1843         }
1844
1845         /*
1846          * keep hooks happy by forcing a temporary shallow file via
1847          * env variable because we can't add --shallow-file to every
1848          * command. check_everything_connected() will be done with
1849          * true .git/shallow though.
1850          */
1851         setenv(GIT_SHALLOW_FILE_ENVIRONMENT, alt_shallow_file, 1);
1852 }
1853
1854 static void update_shallow_info(struct command *commands,
1855                                 struct shallow_info *si,
1856                                 struct oid_array *ref)
1857 {
1858         struct command *cmd;
1859         int *ref_status;
1860         remove_nonexistent_theirs_shallow(si);
1861         if (!si->nr_ours && !si->nr_theirs) {
1862                 shallow_update = 0;
1863                 return;
1864         }
1865
1866         for (cmd = commands; cmd; cmd = cmd->next) {
1867                 if (is_null_oid(&cmd->new_oid))
1868                         continue;
1869                 oid_array_append(ref, &cmd->new_oid);
1870                 cmd->index = ref->nr - 1;
1871         }
1872         si->ref = ref;
1873
1874         if (shallow_update) {
1875                 prepare_shallow_update(commands, si);
1876                 return;
1877         }
1878
1879         ALLOC_ARRAY(ref_status, ref->nr);
1880         assign_shallow_commits_to_refs(si, NULL, ref_status);
1881         for (cmd = commands; cmd; cmd = cmd->next) {
1882                 if (is_null_oid(&cmd->new_oid))
1883                         continue;
1884                 if (ref_status[cmd->index]) {
1885                         cmd->error_string = "shallow update not allowed";
1886                         cmd->skip_update = 1;
1887                 }
1888         }
1889         free(ref_status);
1890 }
1891
1892 static void report(struct command *commands, const char *unpack_status)
1893 {
1894         struct command *cmd;
1895         struct strbuf buf = STRBUF_INIT;
1896
1897         packet_buf_write(&buf, "unpack %s\n",
1898                          unpack_status ? unpack_status : "ok");
1899         for (cmd = commands; cmd; cmd = cmd->next) {
1900                 if (!cmd->error_string)
1901                         packet_buf_write(&buf, "ok %s\n",
1902                                          cmd->ref_name);
1903                 else
1904                         packet_buf_write(&buf, "ng %s %s\n",
1905                                          cmd->ref_name, cmd->error_string);
1906         }
1907         packet_buf_flush(&buf);
1908
1909         if (use_sideband)
1910                 send_sideband(1, 1, buf.buf, buf.len, use_sideband);
1911         else
1912                 write_or_die(1, buf.buf, buf.len);
1913         strbuf_release(&buf);
1914 }
1915
1916 static int delete_only(struct command *commands)
1917 {
1918         struct command *cmd;
1919         for (cmd = commands; cmd; cmd = cmd->next) {
1920                 if (!is_null_oid(&cmd->new_oid))
1921                         return 0;
1922         }
1923         return 1;
1924 }
1925
1926 int cmd_receive_pack(int argc, const char **argv, const char *prefix)
1927 {
1928         int advertise_refs = 0;
1929         struct command *commands;
1930         struct oid_array shallow = OID_ARRAY_INIT;
1931         struct oid_array ref = OID_ARRAY_INIT;
1932         struct shallow_info si;
1933
1934         struct option options[] = {
1935                 OPT__QUIET(&quiet, N_("quiet")),
1936                 OPT_HIDDEN_BOOL(0, "stateless-rpc", &stateless_rpc, NULL),
1937                 OPT_HIDDEN_BOOL(0, "advertise-refs", &advertise_refs, NULL),
1938                 OPT_HIDDEN_BOOL(0, "reject-thin-pack-for-testing", &reject_thin, NULL),
1939                 OPT_END()
1940         };
1941
1942         packet_trace_identity("receive-pack");
1943
1944         argc = parse_options(argc, argv, prefix, options, receive_pack_usage, 0);
1945
1946         if (argc > 1)
1947                 usage_msg_opt(_("Too many arguments."), receive_pack_usage, options);
1948         if (argc == 0)
1949                 usage_msg_opt(_("You must specify a directory."), receive_pack_usage, options);
1950
1951         service_dir = argv[0];
1952
1953         setup_path();
1954
1955         if (!enter_repo(service_dir, 0))
1956                 die("'%s' does not appear to be a git repository", service_dir);
1957
1958         git_config(receive_pack_config, NULL);
1959         if (cert_nonce_seed)
1960                 push_cert_nonce = prepare_push_cert_nonce(service_dir, time(NULL));
1961
1962         if (0 <= transfer_unpack_limit)
1963                 unpack_limit = transfer_unpack_limit;
1964         else if (0 <= receive_unpack_limit)
1965                 unpack_limit = receive_unpack_limit;
1966
1967         switch (determine_protocol_version_server()) {
1968         case protocol_v1:
1969                 /*
1970                  * v1 is just the original protocol with a version string,
1971                  * so just fall through after writing the version string.
1972                  */
1973                 if (advertise_refs || !stateless_rpc)
1974                         packet_write_fmt(1, "version 1\n");
1975
1976                 /* fallthrough */
1977         case protocol_v0:
1978                 break;
1979         case protocol_unknown_version:
1980                 BUG("unknown protocol version");
1981         }
1982
1983         if (advertise_refs || !stateless_rpc) {
1984                 write_head_info();
1985         }
1986         if (advertise_refs)
1987                 return 0;
1988
1989         if ((commands = read_head_info(&shallow)) != NULL) {
1990                 const char *unpack_status = NULL;
1991                 struct string_list push_options = STRING_LIST_INIT_DUP;
1992
1993                 if (use_push_options)
1994                         read_push_options(&push_options);
1995                 if (!check_cert_push_options(&push_options)) {
1996                         struct command *cmd;
1997                         for (cmd = commands; cmd; cmd = cmd->next)
1998                                 cmd->error_string = "inconsistent push options";
1999                 }
2000
2001                 prepare_shallow_info(&si, &shallow);
2002                 if (!si.nr_ours && !si.nr_theirs)
2003                         shallow_update = 0;
2004                 if (!delete_only(commands)) {
2005                         unpack_status = unpack_with_sideband(&si);
2006                         update_shallow_info(commands, &si, &ref);
2007                 }
2008                 use_keepalive = KEEPALIVE_ALWAYS;
2009                 execute_commands(commands, unpack_status, &si,
2010                                  &push_options);
2011                 if (pack_lockfile)
2012                         unlink_or_warn(pack_lockfile);
2013                 if (report_status)
2014                         report(commands, unpack_status);
2015                 run_receive_hook(commands, "post-receive", 1,
2016                                  &push_options);
2017                 run_update_post_hook(commands);
2018                 string_list_clear(&push_options, 0);
2019                 if (auto_gc) {
2020                         const char *argv_gc_auto[] = {
2021                                 "gc", "--auto", "--quiet", NULL,
2022                         };
2023                         struct child_process proc = CHILD_PROCESS_INIT;
2024
2025                         proc.no_stdin = 1;
2026                         proc.stdout_to_stderr = 1;
2027                         proc.err = use_sideband ? -1 : 0;
2028                         proc.git_cmd = 1;
2029                         proc.argv = argv_gc_auto;
2030
2031                         close_all_packs();
2032                         if (!start_command(&proc)) {
2033                                 if (use_sideband)
2034                                         copy_to_sideband(proc.err, -1, NULL);
2035                                 finish_command(&proc);
2036                         }
2037                 }
2038                 if (auto_update_server_info)
2039                         update_server_info(0);
2040                 clear_shallow_info(&si);
2041         }
2042         if (use_sideband)
2043                 packet_flush(1);
2044         oid_array_clear(&shallow);
2045         oid_array_clear(&ref);
2046         free((void *)push_cert_nonce);
2047         return 0;
2048 }