sbin/hastd/hastd.c

   1 /*-
   2  * Copyright (c) 2009-2010 The FreeBSD Foundation
   3  * Copyright (c) 2010-2011 Pawel Jakub Dawidek <pawel@dawidek.net>
   4  * All rights reserved.
   5  *
   6  * This software was developed by Pawel Jakub Dawidek under sponsorship from
   7  * the FreeBSD Foundation.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
  19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28  * SUCH DAMAGE.
  29  */
  30
  31 #include <sys/cdefs.h>
  32 __FBSDID("$FreeBSD$");
  33
  34 #include <sys/param.h>
  35 #include <sys/linker.h>
  36 #include <sys/module.h>
  37 #include <sys/stat.h>
  38 #include <sys/wait.h>
  39
  40 #include <err.h>
  41 #include <errno.h>
  42 #include <libutil.h>
  43 #include <signal.h>
  44 #include <stdbool.h>
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <string.h>
  48 #include <sysexits.h>
  49 #include <time.h>
  50 #include <unistd.h>
  51
  52 #include <activemap.h>
  53 #include <pjdlog.h>
  54
  55 #include "control.h"
  56 #include "event.h"
  57 #include "hast.h"
  58 #include "hast_proto.h"
  59 #include "hastd.h"
  60 #include "hooks.h"
  61 #include "subr.h"
  62
  63 /* Path to configuration file. */
  64 const char *cfgpath = HAST_CONFIG;
  65 /* Hastd configuration. */
  66 static struct hastd_config *cfg;
  67 /* Was SIGINT or SIGTERM signal received? */
  68 bool sigexit_received = false;
  69 /* PID file handle. */
  70 struct pidfh *pfh;
  71
  72 /* How often check for hooks running for too long. */
  73 #define REPORT_INTERVAL 5
  74
  75 static void
  76 usage(void)
  77 {
  78
  79         errx(EX_USAGE, "[-dFh] [-c config] [-P pidfile]");
  80 }
  81
  82 static void
  83 g_gate_load(void)
  84 {
  85
  86         if (modfind("g_gate") == -1) {
  87                 /* Not present in kernel, try loading it. */
  88                 if (kldload("geom_gate") == -1 || modfind("g_gate") == -1) {
  89                         if (errno != EEXIST) {
  90                                 pjdlog_exit(EX_OSERR,
  91                                     "Unable to load geom_gate module");
  92                         }
  93                 }
  94         }
  95 }
  96
  97 void
  98 descriptors_cleanup(struct hast_resource *res)
  99 {
 100         struct hast_resource *tres;
 101         struct hastd_listen *lst;
 102
 103         TAILQ_FOREACH(tres, &cfg->hc_resources, hr_next) {
 104                 if (tres == res) {
 105                         PJDLOG_VERIFY(res->hr_role == HAST_ROLE_SECONDARY ||
 106                             (res->hr_remotein == NULL &&
 107                              res->hr_remoteout == NULL));
 108                         continue;
 109                 }
 110                 if (tres->hr_remotein != NULL)
 111                         proto_close(tres->hr_remotein);
 112                 if (tres->hr_remoteout != NULL)
 113                         proto_close(tres->hr_remoteout);
 114                 if (tres->hr_ctrl != NULL)
 115                         proto_close(tres->hr_ctrl);
 116                 if (tres->hr_event != NULL)
 117                         proto_close(tres->hr_event);
 118                 if (tres->hr_conn != NULL)
 119                         proto_close(tres->hr_conn);
 120         }
 121         if (cfg->hc_controlin != NULL)
 122                 proto_close(cfg->hc_controlin);
 123         proto_close(cfg->hc_controlconn);
 124         TAILQ_FOREACH(lst, &cfg->hc_listen, hl_next) {
 125                 if (lst->hl_conn != NULL)
 126                         proto_close(lst->hl_conn);
 127         }
 128         (void)pidfile_close(pfh);
 129         hook_fini();
 130         pjdlog_fini();
 131 }
 132
 133 static const char *
 134 dtype2str(mode_t mode)
 135 {
 136
 137         if (S_ISBLK(mode))
 138                 return ("block device");
 139         else if (S_ISCHR(mode))
 140                 return ("character device");
 141         else if (S_ISDIR(mode))
 142                 return ("directory");
 143         else if (S_ISFIFO(mode))
 144                 return ("pipe or FIFO");
 145         else if (S_ISLNK(mode))
 146                 return ("symbolic link");
 147         else if (S_ISREG(mode))
 148                 return ("regular file");
 149         else if (S_ISSOCK(mode))
 150                 return ("socket");
 151         else if (S_ISWHT(mode))
 152                 return ("whiteout");
 153         else
 154                 return ("unknown");
 155 }
 156
 157 void
 158 descriptors_assert(const struct hast_resource *res, int pjdlogmode)
 159 {
 160         char msg[256];
 161         struct stat sb;
 162         long maxfd;
 163         bool isopen;
 164         mode_t mode;
 165         int fd;
 166
 167         /*
 168          * At this point descriptor to syslog socket is closed, so if we want
 169          * to log assertion message, we have to first store it in 'msg' local
 170          * buffer and then open syslog socket and log it.
 171          */
 172         msg[0] = '\0';
 173
 174         maxfd = sysconf(_SC_OPEN_MAX);
 175         if (maxfd < 0) {
 176                 pjdlog_init(pjdlogmode);
 177                 pjdlog_prefix_set("[%s] (%s) ", res->hr_name,
 178                     role2str(res->hr_role));
 179                 pjdlog_errno(LOG_WARNING, "sysconf(_SC_OPEN_MAX) failed");
 180                 pjdlog_fini();
 181                 maxfd = 16384;
 182         }
 183         for (fd = 0; fd <= maxfd; fd++) {
 184                 if (fstat(fd, &sb) == 0) {
 185                         isopen = true;
 186                         mode = sb.st_mode;
 187                 } else if (errno == EBADF) {
 188                         isopen = false;
 189                         mode = 0;
 190                 } else {
 191                         (void)snprintf(msg, sizeof(msg),
 192                             "Unable to fstat descriptor %d: %s", fd,
 193                             strerror(errno));
 194                         break;
 195                 }
 196                 if (fd == STDIN_FILENO || fd == STDOUT_FILENO ||
 197                     fd == STDERR_FILENO) {
 198                         if (!isopen) {
 199                                 (void)snprintf(msg, sizeof(msg),
 200                                     "Descriptor %d (%s) is closed, but should be open.",
 201                                     fd, (fd == STDIN_FILENO ? "stdin" :
 202                                     (fd == STDOUT_FILENO ? "stdout" : "stderr")));
 203                                 break;
 204                         }
 205                 } else if (fd == proto_descriptor(res->hr_event)) {
 206                         if (!isopen) {
 207                                 (void)snprintf(msg, sizeof(msg),
 208                                     "Descriptor %d (event) is closed, but should be open.",
 209                                     fd);
 210                                 break;
 211                         }
 212                         if (!S_ISSOCK(mode)) {
 213                                 (void)snprintf(msg, sizeof(msg),
 214                                     "Descriptor %d (event) is %s, but should be %s.",
 215                                     fd, dtype2str(mode), dtype2str(S_IFSOCK));
 216                                 break;
 217                         }
 218                 } else if (fd == proto_descriptor(res->hr_ctrl)) {
 219                         if (!isopen) {
 220                                 (void)snprintf(msg, sizeof(msg),
 221                                     "Descriptor %d (ctrl) is closed, but should be open.",
 222                                     fd);
 223                                 break;
 224                         }
 225                         if (!S_ISSOCK(mode)) {
 226                                 (void)snprintf(msg, sizeof(msg),
 227                                     "Descriptor %d (ctrl) is %s, but should be %s.",
 228                                     fd, dtype2str(mode), dtype2str(S_IFSOCK));
 229                                 break;
 230                         }
 231                 } else if (res->hr_role == HAST_ROLE_PRIMARY &&
 232                     fd == proto_descriptor(res->hr_conn)) {
 233                         if (!isopen) {
 234                                 (void)snprintf(msg, sizeof(msg),
 235                                     "Descriptor %d (conn) is closed, but should be open.",
 236                                     fd);
 237                                 break;
 238                         }
 239                         if (!S_ISSOCK(mode)) {
 240                                 (void)snprintf(msg, sizeof(msg),
 241                                     "Descriptor %d (conn) is %s, but should be %s.",
 242                                     fd, dtype2str(mode), dtype2str(S_IFSOCK));
 243                                 break;
 244                         }
 245                 } else if (res->hr_role == HAST_ROLE_SECONDARY &&
 246                     res->hr_conn != NULL &&
 247                     fd == proto_descriptor(res->hr_conn)) {
 248                         if (isopen) {
 249                                 (void)snprintf(msg, sizeof(msg),
 250                                     "Descriptor %d (conn) is open, but should be closed.",
 251                                     fd);
 252                                 break;
 253                         }
 254                 } else if (res->hr_role == HAST_ROLE_SECONDARY &&
 255                     fd == proto_descriptor(res->hr_remotein)) {
 256                         if (!isopen) {
 257                                 (void)snprintf(msg, sizeof(msg),
 258                                     "Descriptor %d (remote in) is closed, but should be open.",
 259                                     fd);
 260                                 break;
 261                         }
 262                         if (!S_ISSOCK(mode)) {
 263                                 (void)snprintf(msg, sizeof(msg),
 264                                     "Descriptor %d (remote in) is %s, but should be %s.",
 265                                     fd, dtype2str(mode), dtype2str(S_IFSOCK));
 266                                 break;
 267                         }
 268                 } else if (res->hr_role == HAST_ROLE_SECONDARY &&
 269                     fd == proto_descriptor(res->hr_remoteout)) {
 270                         if (!isopen) {
 271                                 (void)snprintf(msg, sizeof(msg),
 272                                     "Descriptor %d (remote out) is closed, but should be open.",
 273                                     fd);
 274                                 break;
 275                         }
 276                         if (!S_ISSOCK(mode)) {
 277                                 (void)snprintf(msg, sizeof(msg),
 278                                     "Descriptor %d (remote out) is %s, but should be %s.",
 279                                     fd, dtype2str(mode), dtype2str(S_IFSOCK));
 280                                 break;
 281                         }
 282                 } else {
 283                         if (isopen) {
 284                                 (void)snprintf(msg, sizeof(msg),
 285                                     "Descriptor %d is open (%s), but should be closed.",
 286                                     fd, dtype2str(mode));
 287                                 break;
 288                         }
 289                 }
 290         }
 291         if (msg[0] != '\0') {
 292                 pjdlog_init(pjdlogmode);
 293                 pjdlog_prefix_set("[%s] (%s) ", res->hr_name,
 294                     role2str(res->hr_role));
 295                 PJDLOG_ABORT("%s", msg);
 296         }
 297 }
 298
 299 static void
 300 child_exit_log(unsigned int pid, int status)
 301 {
 302
 303         if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
 304                 pjdlog_debug(1, "Worker process exited gracefully (pid=%u).",
 305                     pid);
 306         } else if (WIFSIGNALED(status)) {
 307                 pjdlog_error("Worker process killed (pid=%u, signal=%d).",
 308                     pid, WTERMSIG(status));
 309         } else {
 310                 pjdlog_error("Worker process exited ungracefully (pid=%u, exitcode=%d).",
 311                     pid, WIFEXITED(status) ? WEXITSTATUS(status) : -1);
 312         }
 313 }
 314
 315 static void
 316 child_exit(void)
 317 {
 318         struct hast_resource *res;
 319         int status;
 320         pid_t pid;
 321
 322         while ((pid = wait3(&status, WNOHANG, NULL)) > 0) {
 323                 /* Find resource related to the process that just exited. */
 324                 TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
 325                         if (pid == res->hr_workerpid)
 326                                 break;
 327                 }
 328                 if (res == NULL) {
 329                         /*
 330                          * This can happen when new connection arrives and we
 331                          * cancel child responsible for the old one or if this
 332                          * was hook which we executed.
 333                          */
 334                         hook_check_one(pid, status);
 335                         continue;
 336                 }
 337                 pjdlog_prefix_set("[%s] (%s) ", res->hr_name,
 338                     role2str(res->hr_role));
 339                 child_exit_log(pid, status);
 340                 child_cleanup(res);
 341                 if (res->hr_role == HAST_ROLE_PRIMARY) {
 342                         /*
 343                          * Restart child process if it was killed by signal
 344                          * or exited because of temporary problem.
 345                          */
 346                         if (WIFSIGNALED(status) ||
 347                             (WIFEXITED(status) &&
 348                              WEXITSTATUS(status) == EX_TEMPFAIL)) {
 349                                 sleep(1);
 350                                 pjdlog_info("Restarting worker process.");
 351                                 hastd_primary(res);
 352                         } else {
 353                                 res->hr_role = HAST_ROLE_INIT;
 354                                 pjdlog_info("Changing resource role back to %s.",
 355                                     role2str(res->hr_role));
 356                         }
 357                 }
 358                 pjdlog_prefix_set("%s", "");
 359         }
 360 }
 361
 362 static bool
 363 resource_needs_restart(const struct hast_resource *res0,
 364     const struct hast_resource *res1)
 365 {
 366
 367         PJDLOG_ASSERT(strcmp(res0->hr_name, res1->hr_name) == 0);
 368
 369         if (strcmp(res0->hr_provname, res1->hr_provname) != 0)
 370                 return (true);
 371         if (strcmp(res0->hr_localpath, res1->hr_localpath) != 0)
 372                 return (true);
 373         if (res0->hr_role == HAST_ROLE_INIT ||
 374             res0->hr_role == HAST_ROLE_SECONDARY) {
 375                 if (strcmp(res0->hr_remoteaddr, res1->hr_remoteaddr) != 0)
 376                         return (true);
 377                 if (strcmp(res0->hr_sourceaddr, res1->hr_sourceaddr) != 0)
 378                         return (true);
 379                 if (res0->hr_replication != res1->hr_replication)
 380                         return (true);
 381                 if (res0->hr_checksum != res1->hr_checksum)
 382                         return (true);
 383                 if (res0->hr_compression != res1->hr_compression)
 384                         return (true);
 385                 if (res0->hr_timeout != res1->hr_timeout)
 386                         return (true);
 387                 if (strcmp(res0->hr_exec, res1->hr_exec) != 0)
 388                         return (true);
 389         }
 390         return (false);
 391 }
 392
 393 static bool
 394 resource_needs_reload(const struct hast_resource *res0,
 395     const struct hast_resource *res1)
 396 {
 397
 398         PJDLOG_ASSERT(strcmp(res0->hr_name, res1->hr_name) == 0);
 399         PJDLOG_ASSERT(strcmp(res0->hr_provname, res1->hr_provname) == 0);
 400         PJDLOG_ASSERT(strcmp(res0->hr_localpath, res1->hr_localpath) == 0);
 401
 402         if (res0->hr_role != HAST_ROLE_PRIMARY)
 403                 return (false);
 404
 405         if (strcmp(res0->hr_remoteaddr, res1->hr_remoteaddr) != 0)
 406                 return (true);
 407         if (strcmp(res0->hr_sourceaddr, res1->hr_sourceaddr) != 0)
 408                 return (true);
 409         if (res0->hr_replication != res1->hr_replication)
 410                 return (true);
 411         if (res0->hr_checksum != res1->hr_checksum)
 412                 return (true);
 413         if (res0->hr_compression != res1->hr_compression)
 414                 return (true);
 415         if (res0->hr_timeout != res1->hr_timeout)
 416                 return (true);
 417         if (strcmp(res0->hr_exec, res1->hr_exec) != 0)
 418                 return (true);
 419         return (false);
 420 }
 421
 422 static void
 423 resource_reload(const struct hast_resource *res)
 424 {
 425         struct nv *nvin, *nvout;
 426         int error;
 427
 428         PJDLOG_ASSERT(res->hr_role == HAST_ROLE_PRIMARY);
 429
 430         nvout = nv_alloc();
 431         nv_add_uint8(nvout, CONTROL_RELOAD, "cmd");
 432         nv_add_string(nvout, res->hr_remoteaddr, "remoteaddr");
 433         nv_add_string(nvout, res->hr_sourceaddr, "sourceaddr");
 434         nv_add_int32(nvout, (int32_t)res->hr_replication, "replication");
 435         nv_add_int32(nvout, (int32_t)res->hr_checksum, "checksum");
 436         nv_add_int32(nvout, (int32_t)res->hr_compression, "compression");
 437         nv_add_int32(nvout, (int32_t)res->hr_timeout, "timeout");
 438         nv_add_string(nvout, res->hr_exec, "exec");
 439         if (nv_error(nvout) != 0) {
 440                 nv_free(nvout);
 441                 pjdlog_error("Unable to allocate header for reload message.");
 442                 return;
 443         }
 444         if (hast_proto_send(res, res->hr_ctrl, nvout, NULL, 0) < 0) {
 445                 pjdlog_errno(LOG_ERR, "Unable to send reload message");
 446                 nv_free(nvout);
 447                 return;
 448         }
 449         nv_free(nvout);
 450
 451         /* Receive response. */
 452         if (hast_proto_recv_hdr(res->hr_ctrl, &nvin) < 0) {
 453                 pjdlog_errno(LOG_ERR, "Unable to receive reload reply");
 454                 return;
 455         }
 456         error = nv_get_int16(nvin, "error");
 457         nv_free(nvin);
 458         if (error != 0) {
 459                 pjdlog_common(LOG_ERR, 0, error, "Reload failed");
 460                 return;
 461         }
 462 }
 463
 464 static void
 465 hastd_reload(void)
 466 {
 467         struct hastd_config *newcfg;
 468         struct hast_resource *nres, *cres, *tres;
 469         struct hastd_listen *nlst, *clst;
 470         unsigned int nlisten;
 471         uint8_t role;
 472
 473         pjdlog_info("Reloading configuration...");
 474
 475         newcfg = yy_config_parse(cfgpath, false);
 476         if (newcfg == NULL)
 477                 goto failed;
 478
 479         /*
 480          * Check if control address has changed.
 481          */
 482         if (strcmp(cfg->hc_controladdr, newcfg->hc_controladdr) != 0) {
 483                 if (proto_server(newcfg->hc_controladdr,
 484                     &newcfg->hc_controlconn) < 0) {
 485                         pjdlog_errno(LOG_ERR,
 486                             "Unable to listen on control address %s",
 487                             newcfg->hc_controladdr);
 488                         goto failed;
 489                 }
 490         }
 491         /*
 492          * Check if any listen address has changed.
 493          */
 494         nlisten = 0;
 495         TAILQ_FOREACH(nlst, &newcfg->hc_listen, hl_next) {
 496                 TAILQ_FOREACH(clst, &cfg->hc_listen, hl_next) {
 497                         if (strcmp(nlst->hl_addr, clst->hl_addr) == 0)
 498                                 break;
 499                 }
 500                 if (clst != NULL && clst->hl_conn != NULL) {
 501                         pjdlog_info("Keep listening on address %s.",
 502                             nlst->hl_addr);
 503                         nlst->hl_conn = clst->hl_conn;
 504                         nlisten++;
 505                 } else if (proto_server(nlst->hl_addr, &nlst->hl_conn) == 0) {
 506                         pjdlog_info("Listening on new address %s.",
 507                             nlst->hl_addr);
 508                         nlisten++;
 509                 } else {
 510                         pjdlog_errno(LOG_WARNING,
 511                             "Unable to listen on address %s", nlst->hl_addr);
 512                 }
 513         }
 514         if (nlisten == 0) {
 515                 pjdlog_error("No addresses to listen on.");
 516                 goto failed;
 517         }
 518
 519         /* No failures from now on. */
 520
 521         /*
 522          * Switch to new control socket.
 523          */
 524         if (newcfg->hc_controlconn != NULL) {
 525                 pjdlog_info("Control socket changed from %s to %s.",
 526                     cfg->hc_controladdr, newcfg->hc_controladdr);
 527                 proto_close(cfg->hc_controlconn);
 528                 cfg->hc_controlconn = newcfg->hc_controlconn;
 529                 newcfg->hc_controlconn = NULL;
 530                 strlcpy(cfg->hc_controladdr, newcfg->hc_controladdr,
 531                     sizeof(cfg->hc_controladdr));
 532         }
 533         /*
 534          * Switch to new listen addresses. Close all that were removed.
 535          */
 536         while ((clst = TAILQ_FIRST(&cfg->hc_listen)) != NULL) {
 537                 TAILQ_FOREACH(nlst, &newcfg->hc_listen, hl_next) {
 538                         if (strcmp(nlst->hl_addr, clst->hl_addr) == 0)
 539                                 break;
 540                 }
 541                 if (nlst == NULL && clst->hl_conn != NULL) {
 542                         proto_close(clst->hl_conn);
 543                         pjdlog_info("No longer listening on address %s.",
 544                             clst->hl_addr);
 545                 }
 546                 TAILQ_REMOVE(&cfg->hc_listen, clst, hl_next);
 547                 free(clst);
 548         }
 549         TAILQ_CONCAT(&cfg->hc_listen, &newcfg->hc_listen, hl_next);
 550
 551         /*
 552          * Stop and remove resources that were removed from the configuration.
 553          */
 554         TAILQ_FOREACH_SAFE(cres, &cfg->hc_resources, hr_next, tres) {
 555                 TAILQ_FOREACH(nres, &newcfg->hc_resources, hr_next) {
 556                         if (strcmp(cres->hr_name, nres->hr_name) == 0)
 557                                 break;
 558                 }
 559                 if (nres == NULL) {
 560                         control_set_role(cres, HAST_ROLE_INIT);
 561                         TAILQ_REMOVE(&cfg->hc_resources, cres, hr_next);
 562                         pjdlog_info("Resource %s removed.", cres->hr_name);
 563                         free(cres);
 564                 }
 565         }
 566         /*
 567          * Move new resources to the current configuration.
 568          */
 569         TAILQ_FOREACH_SAFE(nres, &newcfg->hc_resources, hr_next, tres) {
 570                 TAILQ_FOREACH(cres, &cfg->hc_resources, hr_next) {
 571                         if (strcmp(cres->hr_name, nres->hr_name) == 0)
 572                                 break;
 573                 }
 574                 if (cres == NULL) {
 575                         TAILQ_REMOVE(&newcfg->hc_resources, nres, hr_next);
 576                         TAILQ_INSERT_TAIL(&cfg->hc_resources, nres, hr_next);
 577                         pjdlog_info("Resource %s added.", nres->hr_name);
 578                 }
 579         }
 580         /*
 581          * Deal with modified resources.
 582          * Depending on what has changed exactly we might want to perform
 583          * different actions.
 584          *
 585          * We do full resource restart in the following situations:
 586          * Resource role is INIT or SECONDARY.
 587          * Resource role is PRIMARY and path to local component or provider
 588          * name has changed.
 589          * In case of PRIMARY, the worker process will be killed and restarted,
 590          * which also means removing /dev/hast/<name> provider and
 591          * recreating it.
 592          *
 593          * We do just reload (send SIGHUP to worker process) if we act as
 594          * PRIMARY, but only if remote address, replication mode, timeout or
 595          * execution path has changed. For those, there is no need to restart
 596          * worker process.
 597          * If PRIMARY receives SIGHUP, it will reconnect if remote address or
 598          * replication mode has changed or simply set new timeout if only
 599          * timeout has changed.
 600          */
 601         TAILQ_FOREACH_SAFE(nres, &newcfg->hc_resources, hr_next, tres) {
 602                 TAILQ_FOREACH(cres, &cfg->hc_resources, hr_next) {
 603                         if (strcmp(cres->hr_name, nres->hr_name) == 0)
 604                                 break;
 605                 }
 606                 PJDLOG_ASSERT(cres != NULL);
 607                 if (resource_needs_restart(cres, nres)) {
 608                         pjdlog_info("Resource %s configuration was modified, restarting it.",
 609                             cres->hr_name);
 610                         role = cres->hr_role;
 611                         control_set_role(cres, HAST_ROLE_INIT);
 612                         TAILQ_REMOVE(&cfg->hc_resources, cres, hr_next);
 613                         free(cres);
 614                         TAILQ_REMOVE(&newcfg->hc_resources, nres, hr_next);
 615                         TAILQ_INSERT_TAIL(&cfg->hc_resources, nres, hr_next);
 616                         control_set_role(nres, role);
 617                 } else if (resource_needs_reload(cres, nres)) {
 618                         pjdlog_info("Resource %s configuration was modified, reloading it.",
 619                             cres->hr_name);
 620                         strlcpy(cres->hr_remoteaddr, nres->hr_remoteaddr,
 621                             sizeof(cres->hr_remoteaddr));
 622                         strlcpy(cres->hr_sourceaddr, nres->hr_sourceaddr,
 623                             sizeof(cres->hr_sourceaddr));
 624                         cres->hr_replication = nres->hr_replication;
 625                         cres->hr_checksum = nres->hr_checksum;
 626                         cres->hr_compression = nres->hr_compression;
 627                         cres->hr_timeout = nres->hr_timeout;
 628                         strlcpy(cres->hr_exec, nres->hr_exec,
 629                             sizeof(cres->hr_exec));
 630                         if (cres->hr_workerpid != 0)
 631                                 resource_reload(cres);
 632                 }
 633         }
 634
 635         yy_config_free(newcfg);
 636         pjdlog_info("Configuration reloaded successfully.");
 637         return;
 638 failed:
 639         if (newcfg != NULL) {
 640                 if (newcfg->hc_controlconn != NULL)
 641                         proto_close(newcfg->hc_controlconn);
 642                 while ((nlst = TAILQ_FIRST(&newcfg->hc_listen)) != NULL) {
 643                         if (nlst->hl_conn != NULL) {
 644                                 TAILQ_FOREACH(clst, &cfg->hc_listen, hl_next) {
 645                                         if (strcmp(nlst->hl_addr,
 646                                             clst->hl_addr) == 0) {
 647                                                 break;
 648                                         }
 649                                 }
 650                                 if (clst == NULL || clst->hl_conn == NULL)
 651                                         proto_close(nlst->hl_conn);
 652                         }
 653                         TAILQ_REMOVE(&newcfg->hc_listen, nlst, hl_next);
 654                         free(nlst);
 655                 }
 656                 yy_config_free(newcfg);
 657         }
 658         pjdlog_warning("Configuration not reloaded.");
 659 }
 660
 661 static void
 662 terminate_workers(void)
 663 {
 664         struct hast_resource *res;
 665
 666         pjdlog_info("Termination signal received, exiting.");
 667         TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
 668                 if (res->hr_workerpid == 0)
 669                         continue;
 670                 pjdlog_info("Terminating worker process (resource=%s, role=%s, pid=%u).",
 671                     res->hr_name, role2str(res->hr_role), res->hr_workerpid);
 672                 if (kill(res->hr_workerpid, SIGTERM) == 0)
 673                         continue;
 674                 pjdlog_errno(LOG_WARNING,
 675                     "Unable to send signal to worker process (resource=%s, role=%s, pid=%u).",
 676                     res->hr_name, role2str(res->hr_role), res->hr_workerpid);
 677         }
 678 }
 679
 680 static void
 681 listen_accept(struct hastd_listen *lst)
 682 {
 683         struct hast_resource *res;
 684         struct proto_conn *conn;
 685         struct nv *nvin, *nvout, *nverr;
 686         const char *resname;
 687         const unsigned char *token;
 688         char laddr[256], raddr[256];
 689         size_t size;
 690         pid_t pid;
 691         int status;
 692
 693         proto_local_address(lst->hl_conn, laddr, sizeof(laddr));
 694         pjdlog_debug(1, "Accepting connection to %s.", laddr);
 695
 696         if (proto_accept(lst->hl_conn, &conn) < 0) {
 697                 pjdlog_errno(LOG_ERR, "Unable to accept connection %s", laddr);
 698                 return;
 699         }
 700
 701         proto_local_address(conn, laddr, sizeof(laddr));
 702         proto_remote_address(conn, raddr, sizeof(raddr));
 703         pjdlog_info("Connection from %s to %s.", raddr, laddr);
 704
 705         /* Error in setting timeout is not critical, but why should it fail? */
 706         if (proto_timeout(conn, HAST_TIMEOUT) < 0)
 707                 pjdlog_errno(LOG_WARNING, "Unable to set connection timeout");
 708
 709         nvin = nvout = nverr = NULL;
 710
 711         /*
 712          * Before receiving any data see if remote host have access to any
 713          * resource.
 714          */
 715         TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
 716                 if (proto_address_match(conn, res->hr_remoteaddr))
 717                         break;
 718         }
 719         if (res == NULL) {
 720                 pjdlog_error("Client %s isn't known.", raddr);
 721                 goto close;
 722         }
 723         /* Ok, remote host can access at least one resource. */
 724
 725         if (hast_proto_recv_hdr(conn, &nvin) < 0) {
 726                 pjdlog_errno(LOG_ERR, "Unable to receive header from %s",
 727                     raddr);
 728                 goto close;
 729         }
 730
 731         resname = nv_get_string(nvin, "resource");
 732         if (resname == NULL) {
 733                 pjdlog_error("No 'resource' field in the header received from %s.",
 734                     raddr);
 735                 goto close;
 736         }
 737         pjdlog_debug(2, "%s: resource=%s", raddr, resname);
 738         token = nv_get_uint8_array(nvin, &size, "token");
 739         /*
 740          * NULL token means that this is first conection.
 741          */
 742         if (token != NULL && size != sizeof(res->hr_token)) {
 743                 pjdlog_error("Received token of invalid size from %s (expected %zu, got %zu).",
 744                     raddr, sizeof(res->hr_token), size);
 745                 goto close;
 746         }
 747
 748         /*
 749          * From now on we want to send errors to the remote node.
 750          */
 751         nverr = nv_alloc();
 752
 753         /* Find resource related to this connection. */
 754         TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
 755                 if (strcmp(resname, res->hr_name) == 0)
 756                         break;
 757         }
 758         /* Have we found the resource? */
 759         if (res == NULL) {
 760                 pjdlog_error("No resource '%s' as requested by %s.",
 761                     resname, raddr);
 762                 nv_add_stringf(nverr, "errmsg", "Resource not configured.");
 763                 goto fail;
 764         }
 765
 766         /* Now that we know resource name setup log prefix. */
 767         pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
 768
 769         /* Does the remote host have access to this resource? */
 770         if (!proto_address_match(conn, res->hr_remoteaddr)) {
 771                 pjdlog_error("Client %s has no access to the resource.", raddr);
 772                 nv_add_stringf(nverr, "errmsg", "No access to the resource.");
 773                 goto fail;
 774         }
 775         /* Is the resource marked as secondary? */
 776         if (res->hr_role != HAST_ROLE_SECONDARY) {
 777                 pjdlog_warning("We act as %s for the resource and not as %s as requested by %s.",
 778                     role2str(res->hr_role), role2str(HAST_ROLE_SECONDARY),
 779                     raddr);
 780                 nv_add_stringf(nverr, "errmsg",
 781                     "Remote node acts as %s for the resource and not as %s.",
 782                     role2str(res->hr_role), role2str(HAST_ROLE_SECONDARY));
 783                 if (res->hr_role == HAST_ROLE_PRIMARY) {
 784                         /*
 785                          * If we act as primary request the other side to wait
 786                          * for us a bit, as we might be finishing cleanups.
 787                          */
 788                         nv_add_uint8(nverr, 1, "wait");
 789                 }
 790                 goto fail;
 791         }
 792         /* Does token (if exists) match? */
 793         if (token != NULL && memcmp(token, res->hr_token,
 794             sizeof(res->hr_token)) != 0) {
 795                 pjdlog_error("Token received from %s doesn't match.", raddr);
 796                 nv_add_stringf(nverr, "errmsg", "Token doesn't match.");
 797                 goto fail;
 798         }
 799         /*
 800          * If there is no token, but we have half-open connection
 801          * (only remotein) or full connection (worker process is running)
 802          * we have to cancel those and accept the new connection.
 803          */
 804         if (token == NULL) {
 805                 PJDLOG_ASSERT(res->hr_remoteout == NULL);
 806                 pjdlog_debug(1, "Initial connection from %s.", raddr);
 807                 if (res->hr_workerpid != 0) {
 808                         PJDLOG_ASSERT(res->hr_remotein == NULL);
 809                         pjdlog_debug(1,
 810                             "Worker process exists (pid=%u), stopping it.",
 811                             (unsigned int)res->hr_workerpid);
 812                         /* Stop child process. */
 813                         if (kill(res->hr_workerpid, SIGINT) < 0) {
 814                                 pjdlog_errno(LOG_ERR,
 815                                     "Unable to stop worker process (pid=%u)",
 816                                     (unsigned int)res->hr_workerpid);
 817                                 /*
 818                                  * Other than logging the problem we
 819                                  * ignore it - nothing smart to do.
 820                                  */
 821                         }
 822                         /* Wait for it to exit. */
 823                         else if ((pid = waitpid(res->hr_workerpid,
 824                             &status, 0)) != res->hr_workerpid) {
 825                                 /* We can only log the problem. */
 826                                 pjdlog_errno(LOG_ERR,
 827                                     "Waiting for worker process (pid=%u) failed",
 828                                     (unsigned int)res->hr_workerpid);
 829                         } else {
 830                                 child_exit_log(res->hr_workerpid, status);
 831                         }
 832                         child_cleanup(res);
 833                 } else if (res->hr_remotein != NULL) {
 834                         char oaddr[256];
 835
 836                         proto_remote_address(res->hr_remotein, oaddr,
 837                             sizeof(oaddr));
 838                         pjdlog_debug(1,
 839                             "Canceling half-open connection from %s on connection from %s.",
 840                             oaddr, raddr);
 841                         proto_close(res->hr_remotein);
 842                         res->hr_remotein = NULL;
 843                 }
 844         }
 845
 846         /*
 847          * Checks and cleanups are done.
 848          */
 849
 850         if (token == NULL) {
 851                 arc4random_buf(res->hr_token, sizeof(res->hr_token));
 852                 nvout = nv_alloc();
 853                 nv_add_uint8_array(nvout, res->hr_token,
 854                     sizeof(res->hr_token), "token");
 855                 if (nv_error(nvout) != 0) {
 856                         pjdlog_common(LOG_ERR, 0, nv_error(nvout),
 857                             "Unable to prepare return header for %s", raddr);
 858                         nv_add_stringf(nverr, "errmsg",
 859                             "Remote node was unable to prepare return header: %s.",
 860                             strerror(nv_error(nvout)));
 861                         goto fail;
 862                 }
 863                 if (hast_proto_send(NULL, conn, nvout, NULL, 0) < 0) {
 864                         int error = errno;
 865
 866                         pjdlog_errno(LOG_ERR, "Unable to send response to %s",
 867                             raddr);
 868                         nv_add_stringf(nverr, "errmsg",
 869                             "Remote node was unable to send response: %s.",
 870                             strerror(error));
 871                         goto fail;
 872                 }
 873                 res->hr_remotein = conn;
 874                 pjdlog_debug(1, "Incoming connection from %s configured.",
 875                     raddr);
 876         } else {
 877                 res->hr_remoteout = conn;
 878                 pjdlog_debug(1, "Outgoing connection to %s configured.", raddr);
 879                 hastd_secondary(res, nvin);
 880         }
 881         nv_free(nvin);
 882         nv_free(nvout);
 883         nv_free(nverr);
 884         pjdlog_prefix_set("%s", "");
 885         return;
 886 fail:
 887         if (nv_error(nverr) != 0) {
 888                 pjdlog_common(LOG_ERR, 0, nv_error(nverr),
 889                     "Unable to prepare error header for %s", raddr);
 890                 goto close;
 891         }
 892         if (hast_proto_send(NULL, conn, nverr, NULL, 0) < 0) {
 893                 pjdlog_errno(LOG_ERR, "Unable to send error to %s", raddr);
 894                 goto close;
 895         }
 896 close:
 897         if (nvin != NULL)
 898                 nv_free(nvin);
 899         if (nvout != NULL)
 900                 nv_free(nvout);
 901         if (nverr != NULL)
 902                 nv_free(nverr);
 903         proto_close(conn);
 904         pjdlog_prefix_set("%s", "");
 905 }
 906
 907 static void
 908 connection_migrate(struct hast_resource *res)
 909 {
 910         struct proto_conn *conn;
 911         int16_t val = 0;
 912
 913         pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
 914
 915         PJDLOG_ASSERT(res->hr_role == HAST_ROLE_PRIMARY);
 916
 917         if (proto_recv(res->hr_conn, &val, sizeof(val)) < 0) {
 918                 pjdlog_errno(LOG_WARNING,
 919                     "Unable to receive connection command");
 920                 return;
 921         }
 922         if (proto_client(res->hr_sourceaddr[0] != '\0' ? res->hr_sourceaddr : NULL,
 923             res->hr_remoteaddr, &conn) < 0) {
 924                 val = errno;
 925                 pjdlog_errno(LOG_WARNING,
 926                     "Unable to create outgoing connection to %s",
 927                     res->hr_remoteaddr);
 928                 goto out;
 929         }
 930         if (proto_connect(conn, -1) < 0) {
 931                 val = errno;
 932                 pjdlog_errno(LOG_WARNING, "Unable to connect to %s",
 933                     res->hr_remoteaddr);
 934                 proto_close(conn);
 935                 goto out;
 936         }
 937         val = 0;
 938 out:
 939         if (proto_send(res->hr_conn, &val, sizeof(val)) < 0) {
 940                 pjdlog_errno(LOG_WARNING,
 941                     "Unable to send reply to connection request");
 942         }
 943         if (val == 0 && proto_connection_send(res->hr_conn, conn) < 0)
 944                 pjdlog_errno(LOG_WARNING, "Unable to send connection");
 945
 946         pjdlog_prefix_set("%s", "");
 947 }
 948
 949 static void
 950 check_signals(void)
 951 {
 952         struct timespec sigtimeout;
 953         sigset_t mask;
 954         int signo;
 955
 956         sigtimeout.tv_sec = 0;
 957         sigtimeout.tv_nsec = 0;
 958
 959         PJDLOG_VERIFY(sigemptyset(&mask) == 0);
 960         PJDLOG_VERIFY(sigaddset(&mask, SIGHUP) == 0);
 961         PJDLOG_VERIFY(sigaddset(&mask, SIGINT) == 0);
 962         PJDLOG_VERIFY(sigaddset(&mask, SIGTERM) == 0);
 963         PJDLOG_VERIFY(sigaddset(&mask, SIGCHLD) == 0);
 964
 965         while ((signo = sigtimedwait(&mask, NULL, &sigtimeout)) != -1) {
 966                 switch (signo) {
 967                 case SIGINT:
 968                 case SIGTERM:
 969                         sigexit_received = true;
 970                         terminate_workers();
 971                         proto_close(cfg->hc_controlconn);
 972                         exit(EX_OK);
 973                         break;
 974                 case SIGCHLD:
 975                         child_exit();
 976                         break;
 977                 case SIGHUP:
 978                         hastd_reload();
 979                         break;
 980                 default:
 981                         PJDLOG_ABORT("Unexpected signal (%d).", signo);
 982                 }
 983         }
 984 }
 985
 986 static void
 987 main_loop(void)
 988 {
 989         struct hast_resource *res;
 990         struct hastd_listen *lst;
 991         struct timeval seltimeout;
 992         int fd, maxfd, ret;
 993         time_t lastcheck, now;
 994         fd_set rfds;
 995
 996         lastcheck = time(NULL);
 997         seltimeout.tv_sec = REPORT_INTERVAL;
 998         seltimeout.tv_usec = 0;
 999
1000         for (;;) {
1001                 check_signals();
1002
1003                 /* Setup descriptors for select(2). */
1004                 FD_ZERO(&rfds);
1005                 maxfd = fd = proto_descriptor(cfg->hc_controlconn);
1006                 PJDLOG_ASSERT(fd >= 0);
1007                 FD_SET(fd, &rfds);
1008                 TAILQ_FOREACH(lst, &cfg->hc_listen, hl_next) {
1009                         if (lst->hl_conn == NULL)
1010                                 continue;
1011                         fd = proto_descriptor(lst->hl_conn);
1012                         PJDLOG_ASSERT(fd >= 0);
1013                         FD_SET(fd, &rfds);
1014                         maxfd = fd > maxfd ? fd : maxfd;
1015                 }
1016                 TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
1017                         if (res->hr_event == NULL)
1018                                 continue;
1019                         fd = proto_descriptor(res->hr_event);
1020                         PJDLOG_ASSERT(fd >= 0);
1021                         FD_SET(fd, &rfds);
1022                         maxfd = fd > maxfd ? fd : maxfd;
1023                         if (res->hr_role == HAST_ROLE_PRIMARY) {
1024                                 /* Only primary workers asks for connections. */
1025                                 PJDLOG_ASSERT(res->hr_conn != NULL);
1026                                 fd = proto_descriptor(res->hr_conn);
1027                                 PJDLOG_ASSERT(fd >= 0);
1028                                 FD_SET(fd, &rfds);
1029                                 maxfd = fd > maxfd ? fd : maxfd;
1030                         } else {
1031                                 PJDLOG_ASSERT(res->hr_conn == NULL);
1032                         }
1033                 }
1034
1035                 PJDLOG_ASSERT(maxfd + 1 <= (int)FD_SETSIZE);
1036                 ret = select(maxfd + 1, &rfds, NULL, NULL, &seltimeout);
1037                 now = time(NULL);
1038                 if (lastcheck + REPORT_INTERVAL <= now) {
1039                         hook_check();
1040                         lastcheck = now;
1041                 }
1042                 if (ret == 0) {
1043                         /*
1044                          * select(2) timed out, so there should be no
1045                          * descriptors to check.
1046                          */
1047                         continue;
1048                 } else if (ret == -1) {
1049                         if (errno == EINTR)
1050                                 continue;
1051                         KEEP_ERRNO((void)pidfile_remove(pfh));
1052                         pjdlog_exit(EX_OSERR, "select() failed");
1053                 }
1054
1055                 /*
1056                  * Check for signals before we do anything to update our
1057                  * info about terminated workers in the meantime.
1058                  */
1059                 check_signals();
1060
1061                 if (FD_ISSET(proto_descriptor(cfg->hc_controlconn), &rfds))
1062                         control_handle(cfg);
1063                 TAILQ_FOREACH(lst, &cfg->hc_listen, hl_next) {
1064                         if (lst->hl_conn == NULL)
1065                                 continue;
1066                         if (FD_ISSET(proto_descriptor(lst->hl_conn), &rfds))
1067                                 listen_accept(lst);
1068                 }
1069                 TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
1070                         if (res->hr_event == NULL)
1071                                 continue;
1072                         if (FD_ISSET(proto_descriptor(res->hr_event), &rfds)) {
1073                                 if (event_recv(res) == 0)
1074                                         continue;
1075                                 /* The worker process exited? */
1076                                 proto_close(res->hr_event);
1077                                 res->hr_event = NULL;
1078                                 if (res->hr_conn != NULL) {
1079                                         proto_close(res->hr_conn);
1080                                         res->hr_conn = NULL;
1081                                 }
1082                                 continue;
1083                         }
1084                         if (res->hr_role == HAST_ROLE_PRIMARY) {
1085                                 PJDLOG_ASSERT(res->hr_conn != NULL);
1086                                 if (FD_ISSET(proto_descriptor(res->hr_conn),
1087                                     &rfds)) {
1088                                         connection_migrate(res);
1089                                 }
1090                         } else {
1091                                 PJDLOG_ASSERT(res->hr_conn == NULL);
1092                         }
1093                 }
1094         }
1095 }
1096
1097 static void
1098 dummy_sighandler(int sig __unused)
1099 {
1100         /* Nothing to do. */
1101 }
1102
1103 int
1104 main(int argc, char *argv[])
1105 {
1106         struct hastd_listen *lst;
1107         const char *pidfile;
1108         pid_t otherpid;
1109         bool foreground;
1110         int debuglevel;
1111         sigset_t mask;
1112
1113         foreground = false;
1114         debuglevel = 0;
1115         pidfile = HASTD_PIDFILE;
1116
1117         for (;;) {
1118                 int ch;
1119
1120                 ch = getopt(argc, argv, "c:dFhP:");
1121                 if (ch == -1)
1122                         break;
1123                 switch (ch) {
1124                 case 'c':
1125                         cfgpath = optarg;
1126                         break;
1127                 case 'd':
1128                         debuglevel++;
1129                         break;
1130                 case 'F':
1131                         foreground = true;
1132                         break;
1133                 case 'P':
1134                         pidfile = optarg;
1135                         break;
1136                 case 'h':
1137                 default:
1138                         usage();
1139                 }
1140         }
1141         argc -= optind;
1142         argv += optind;
1143
1144         pjdlog_init(PJDLOG_MODE_STD);
1145         pjdlog_debug_set(debuglevel);
1146
1147         g_gate_load();
1148
1149         pfh = pidfile_open(pidfile, 0600, &otherpid);
1150         if (pfh == NULL) {
1151                 if (errno == EEXIST) {
1152                         pjdlog_exitx(EX_TEMPFAIL,
1153                             "Another hastd is already running, pid: %jd.",
1154                             (intmax_t)otherpid);
1155                 }
1156                 /* If we cannot create pidfile from other reasons, only warn. */
1157                 pjdlog_errno(LOG_WARNING, "Unable to open or create pidfile");
1158         }
1159
1160         cfg = yy_config_parse(cfgpath, true);
1161         PJDLOG_ASSERT(cfg != NULL);
1162
1163         /*
1164          * Restore default actions for interesting signals in case parent
1165          * process (like init(8)) decided to ignore some of them (like SIGHUP).
1166          */
1167         PJDLOG_VERIFY(signal(SIGHUP, SIG_DFL) != SIG_ERR);
1168         PJDLOG_VERIFY(signal(SIGINT, SIG_DFL) != SIG_ERR);
1169         PJDLOG_VERIFY(signal(SIGTERM, SIG_DFL) != SIG_ERR);
1170         /*
1171          * Because SIGCHLD is ignored by default, setup dummy handler for it,
1172          * so we can mask it.
1173          */
1174         PJDLOG_VERIFY(signal(SIGCHLD, dummy_sighandler) != SIG_ERR);
1175
1176         PJDLOG_VERIFY(sigemptyset(&mask) == 0);
1177         PJDLOG_VERIFY(sigaddset(&mask, SIGHUP) == 0);
1178         PJDLOG_VERIFY(sigaddset(&mask, SIGINT) == 0);
1179         PJDLOG_VERIFY(sigaddset(&mask, SIGTERM) == 0);
1180         PJDLOG_VERIFY(sigaddset(&mask, SIGCHLD) == 0);
1181         PJDLOG_VERIFY(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
1182
1183         /* Listen on control address. */
1184         if (proto_server(cfg->hc_controladdr, &cfg->hc_controlconn) < 0) {
1185                 KEEP_ERRNO((void)pidfile_remove(pfh));
1186                 pjdlog_exit(EX_OSERR, "Unable to listen on control address %s",
1187                     cfg->hc_controladdr);
1188         }
1189         /* Listen for remote connections. */
1190         TAILQ_FOREACH(lst, &cfg->hc_listen, hl_next) {
1191                 if (proto_server(lst->hl_addr, &lst->hl_conn) < 0) {
1192                         KEEP_ERRNO((void)pidfile_remove(pfh));
1193                         pjdlog_exit(EX_OSERR, "Unable to listen on address %s",
1194                             lst->hl_addr);
1195                 }
1196         }
1197
1198         if (!foreground) {
1199                 if (daemon(0, 0) < 0) {
1200                         KEEP_ERRNO((void)pidfile_remove(pfh));
1201                         pjdlog_exit(EX_OSERR, "Unable to daemonize");
1202                 }
1203
1204                 /* Start logging to syslog. */
1205                 pjdlog_mode_set(PJDLOG_MODE_SYSLOG);
1206
1207                 /* Write PID to a file. */
1208                 if (pidfile_write(pfh) < 0) {
1209                         pjdlog_errno(LOG_WARNING,
1210                             "Unable to write PID to a file");
1211                 }
1212         }
1213
1214         pjdlog_info("Started successfully, running protocol version %d.",
1215             HAST_PROTO_VERSION);
1216
1217         pjdlog_debug(1, "Listening on control address %s.",
1218             cfg->hc_controladdr);
1219         TAILQ_FOREACH(lst, &cfg->hc_listen, hl_next)
1220                 pjdlog_info("Listening on address %s.", lst->hl_addr);
1221
1222         hook_init();
1223
1224         main_loop();
1225
1226         exit(0);
1227 }