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                  * When metaflush has changed we don't really need restart,
 391                  * but it is just easier this way.
 392                  */
 393                 if (res0->hr_metaflush != res1->hr_metaflush)
 394                         return (true);
 395         }
 396         return (false);
 397 }
 398
 399 static bool
 400 resource_needs_reload(const struct hast_resource *res0,
 401     const struct hast_resource *res1)
 402 {
 403
 404         PJDLOG_ASSERT(strcmp(res0->hr_name, res1->hr_name) == 0);
 405         PJDLOG_ASSERT(strcmp(res0->hr_provname, res1->hr_provname) == 0);
 406         PJDLOG_ASSERT(strcmp(res0->hr_localpath, res1->hr_localpath) == 0);
 407
 408         if (res0->hr_role != HAST_ROLE_PRIMARY)
 409                 return (false);
 410
 411         if (strcmp(res0->hr_remoteaddr, res1->hr_remoteaddr) != 0)
 412                 return (true);
 413         if (strcmp(res0->hr_sourceaddr, res1->hr_sourceaddr) != 0)
 414                 return (true);
 415         if (res0->hr_replication != res1->hr_replication)
 416                 return (true);
 417         if (res0->hr_checksum != res1->hr_checksum)
 418                 return (true);
 419         if (res0->hr_compression != res1->hr_compression)
 420                 return (true);
 421         if (res0->hr_timeout != res1->hr_timeout)
 422                 return (true);
 423         if (strcmp(res0->hr_exec, res1->hr_exec) != 0)
 424                 return (true);
 425         if (res0->hr_metaflush != res1->hr_metaflush)
 426                 return (true);
 427         return (false);
 428 }
 429
 430 static void
 431 resource_reload(const struct hast_resource *res)
 432 {
 433         struct nv *nvin, *nvout;
 434         int error;
 435
 436         PJDLOG_ASSERT(res->hr_role == HAST_ROLE_PRIMARY);
 437
 438         nvout = nv_alloc();
 439         nv_add_uint8(nvout, CONTROL_RELOAD, "cmd");
 440         nv_add_string(nvout, res->hr_remoteaddr, "remoteaddr");
 441         nv_add_string(nvout, res->hr_sourceaddr, "sourceaddr");
 442         nv_add_int32(nvout, (int32_t)res->hr_replication, "replication");
 443         nv_add_int32(nvout, (int32_t)res->hr_checksum, "checksum");
 444         nv_add_int32(nvout, (int32_t)res->hr_compression, "compression");
 445         nv_add_int32(nvout, (int32_t)res->hr_timeout, "timeout");
 446         nv_add_string(nvout, res->hr_exec, "exec");
 447         nv_add_int32(nvout, (int32_t)res->hr_metaflush, "metaflush");
 448         if (nv_error(nvout) != 0) {
 449                 nv_free(nvout);
 450                 pjdlog_error("Unable to allocate header for reload message.");
 451                 return;
 452         }
 453         if (hast_proto_send(res, res->hr_ctrl, nvout, NULL, 0) < 0) {
 454                 pjdlog_errno(LOG_ERR, "Unable to send reload message");
 455                 nv_free(nvout);
 456                 return;
 457         }
 458         nv_free(nvout);
 459
 460         /* Receive response. */
 461         if (hast_proto_recv_hdr(res->hr_ctrl, &nvin) < 0) {
 462                 pjdlog_errno(LOG_ERR, "Unable to receive reload reply");
 463                 return;
 464         }
 465         error = nv_get_int16(nvin, "error");
 466         nv_free(nvin);
 467         if (error != 0) {
 468                 pjdlog_common(LOG_ERR, 0, error, "Reload failed");
 469                 return;
 470         }
 471 }
 472
 473 static void
 474 hastd_reload(void)
 475 {
 476         struct hastd_config *newcfg;
 477         struct hast_resource *nres, *cres, *tres;
 478         struct hastd_listen *nlst, *clst;
 479         struct pidfh *newpfh;
 480         unsigned int nlisten;
 481         uint8_t role;
 482         pid_t otherpid;
 483
 484         pjdlog_info("Reloading configuration...");
 485
 486         newpfh = NULL;
 487
 488         newcfg = yy_config_parse(cfgpath, false);
 489         if (newcfg == NULL)
 490                 goto failed;
 491
 492         /*
 493          * Check if control address has changed.
 494          */
 495         if (strcmp(cfg->hc_controladdr, newcfg->hc_controladdr) != 0) {
 496                 if (proto_server(newcfg->hc_controladdr,
 497                     &newcfg->hc_controlconn) < 0) {
 498                         pjdlog_errno(LOG_ERR,
 499                             "Unable to listen on control address %s",
 500                             newcfg->hc_controladdr);
 501                         goto failed;
 502                 }
 503         }
 504         /*
 505          * Check if any listen address has changed.
 506          */
 507         nlisten = 0;
 508         TAILQ_FOREACH(nlst, &newcfg->hc_listen, hl_next) {
 509                 TAILQ_FOREACH(clst, &cfg->hc_listen, hl_next) {
 510                         if (strcmp(nlst->hl_addr, clst->hl_addr) == 0)
 511                                 break;
 512                 }
 513                 if (clst != NULL && clst->hl_conn != NULL) {
 514                         pjdlog_info("Keep listening on address %s.",
 515                             nlst->hl_addr);
 516                         nlst->hl_conn = clst->hl_conn;
 517                         nlisten++;
 518                 } else if (proto_server(nlst->hl_addr, &nlst->hl_conn) == 0) {
 519                         pjdlog_info("Listening on new address %s.",
 520                             nlst->hl_addr);
 521                         nlisten++;
 522                 } else {
 523                         pjdlog_errno(LOG_WARNING,
 524                             "Unable to listen on address %s", nlst->hl_addr);
 525                 }
 526         }
 527         if (nlisten == 0) {
 528                 pjdlog_error("No addresses to listen on.");
 529                 goto failed;
 530         }
 531         /*
 532          * Check if pidfile's path has changed.
 533          */
 534         if (strcmp(cfg->hc_pidfile, newcfg->hc_pidfile) != 0) {
 535                 newpfh = pidfile_open(newcfg->hc_pidfile, 0600, &otherpid);
 536                 if (newpfh == NULL) {
 537                         if (errno == EEXIST) {
 538                                 pjdlog_errno(LOG_WARNING,
 539                                     "Another hastd is already running, pidfile: %s, pid: %jd.",
 540                                     newcfg->hc_pidfile, (intmax_t)otherpid);
 541                         } else {
 542                                 pjdlog_errno(LOG_WARNING,
 543                                     "Unable to open or create pidfile %s",
 544                                     newcfg->hc_pidfile);
 545                         }
 546                 } else if (pidfile_write(newpfh) < 0) {
 547                         /* Write PID to a file. */
 548                         pjdlog_errno(LOG_WARNING,
 549                             "Unable to write PID to file %s",
 550                             newcfg->hc_pidfile);
 551                 } else {
 552                         pjdlog_debug(1, "PID stored in %s.",
 553                             newcfg->hc_pidfile);
 554                 }
 555         }
 556
 557         /* No failures from now on. */
 558
 559         /*
 560          * Switch to new control socket.
 561          */
 562         if (newcfg->hc_controlconn != NULL) {
 563                 pjdlog_info("Control socket changed from %s to %s.",
 564                     cfg->hc_controladdr, newcfg->hc_controladdr);
 565                 proto_close(cfg->hc_controlconn);
 566                 cfg->hc_controlconn = newcfg->hc_controlconn;
 567                 newcfg->hc_controlconn = NULL;
 568                 strlcpy(cfg->hc_controladdr, newcfg->hc_controladdr,
 569                     sizeof(cfg->hc_controladdr));
 570         }
 571         /*
 572          * Switch to new pidfile.
 573          */
 574         (void)pidfile_remove(pfh);
 575         pfh = newpfh;
 576         (void)strlcpy(cfg->hc_pidfile, newcfg->hc_pidfile,
 577             sizeof(cfg->hc_pidfile));
 578         /*
 579          * Switch to new listen addresses. Close all that were removed.
 580          */
 581         while ((clst = TAILQ_FIRST(&cfg->hc_listen)) != NULL) {
 582                 TAILQ_FOREACH(nlst, &newcfg->hc_listen, hl_next) {
 583                         if (strcmp(nlst->hl_addr, clst->hl_addr) == 0)
 584                                 break;
 585                 }
 586                 if (nlst == NULL && clst->hl_conn != NULL) {
 587                         proto_close(clst->hl_conn);
 588                         pjdlog_info("No longer listening on address %s.",
 589                             clst->hl_addr);
 590                 }
 591                 TAILQ_REMOVE(&cfg->hc_listen, clst, hl_next);
 592                 free(clst);
 593         }
 594         TAILQ_CONCAT(&cfg->hc_listen, &newcfg->hc_listen, hl_next);
 595
 596         /*
 597          * Stop and remove resources that were removed from the configuration.
 598          */
 599         TAILQ_FOREACH_SAFE(cres, &cfg->hc_resources, hr_next, tres) {
 600                 TAILQ_FOREACH(nres, &newcfg->hc_resources, hr_next) {
 601                         if (strcmp(cres->hr_name, nres->hr_name) == 0)
 602                                 break;
 603                 }
 604                 if (nres == NULL) {
 605                         control_set_role(cres, HAST_ROLE_INIT);
 606                         TAILQ_REMOVE(&cfg->hc_resources, cres, hr_next);
 607                         pjdlog_info("Resource %s removed.", cres->hr_name);
 608                         free(cres);
 609                 }
 610         }
 611         /*
 612          * Move new resources to the current configuration.
 613          */
 614         TAILQ_FOREACH_SAFE(nres, &newcfg->hc_resources, hr_next, tres) {
 615                 TAILQ_FOREACH(cres, &cfg->hc_resources, hr_next) {
 616                         if (strcmp(cres->hr_name, nres->hr_name) == 0)
 617                                 break;
 618                 }
 619                 if (cres == NULL) {
 620                         TAILQ_REMOVE(&newcfg->hc_resources, nres, hr_next);
 621                         TAILQ_INSERT_TAIL(&cfg->hc_resources, nres, hr_next);
 622                         pjdlog_info("Resource %s added.", nres->hr_name);
 623                 }
 624         }
 625         /*
 626          * Deal with modified resources.
 627          * Depending on what has changed exactly we might want to perform
 628          * different actions.
 629          *
 630          * We do full resource restart in the following situations:
 631          * Resource role is INIT or SECONDARY.
 632          * Resource role is PRIMARY and path to local component or provider
 633          * name has changed.
 634          * In case of PRIMARY, the worker process will be killed and restarted,
 635          * which also means removing /dev/hast/<name> provider and
 636          * recreating it.
 637          *
 638          * We do just reload (send SIGHUP to worker process) if we act as
 639          * PRIMARY, but only if remote address, source address, replication
 640          * mode, timeout, execution path or metaflush has changed.
 641          * For those, there is no need to restart worker process.
 642          * If PRIMARY receives SIGHUP, it will reconnect if remote address or
 643          * source address has changed or it will set new timeout if only timeout
 644          * has changed or it will update metaflush if only metaflush has
 645          * changed.
 646          */
 647         TAILQ_FOREACH_SAFE(nres, &newcfg->hc_resources, hr_next, tres) {
 648                 TAILQ_FOREACH(cres, &cfg->hc_resources, hr_next) {
 649                         if (strcmp(cres->hr_name, nres->hr_name) == 0)
 650                                 break;
 651                 }
 652                 PJDLOG_ASSERT(cres != NULL);
 653                 if (resource_needs_restart(cres, nres)) {
 654                         pjdlog_info("Resource %s configuration was modified, restarting it.",
 655                             cres->hr_name);
 656                         role = cres->hr_role;
 657                         control_set_role(cres, HAST_ROLE_INIT);
 658                         TAILQ_REMOVE(&cfg->hc_resources, cres, hr_next);
 659                         free(cres);
 660                         TAILQ_REMOVE(&newcfg->hc_resources, nres, hr_next);
 661                         TAILQ_INSERT_TAIL(&cfg->hc_resources, nres, hr_next);
 662                         control_set_role(nres, role);
 663                 } else if (resource_needs_reload(cres, nres)) {
 664                         pjdlog_info("Resource %s configuration was modified, reloading it.",
 665                             cres->hr_name);
 666                         strlcpy(cres->hr_remoteaddr, nres->hr_remoteaddr,
 667                             sizeof(cres->hr_remoteaddr));
 668                         strlcpy(cres->hr_sourceaddr, nres->hr_sourceaddr,
 669                             sizeof(cres->hr_sourceaddr));
 670                         cres->hr_replication = nres->hr_replication;
 671                         cres->hr_checksum = nres->hr_checksum;
 672                         cres->hr_compression = nres->hr_compression;
 673                         cres->hr_timeout = nres->hr_timeout;
 674                         strlcpy(cres->hr_exec, nres->hr_exec,
 675                             sizeof(cres->hr_exec));
 676                         cres->hr_metaflush = nres->hr_metaflush;
 677                         if (cres->hr_workerpid != 0)
 678                                 resource_reload(cres);
 679                 }
 680         }
 681
 682         yy_config_free(newcfg);
 683         pjdlog_info("Configuration reloaded successfully.");
 684         return;
 685 failed:
 686         if (newcfg != NULL) {
 687                 if (newcfg->hc_controlconn != NULL)
 688                         proto_close(newcfg->hc_controlconn);
 689                 while ((nlst = TAILQ_FIRST(&newcfg->hc_listen)) != NULL) {
 690                         if (nlst->hl_conn != NULL) {
 691                                 TAILQ_FOREACH(clst, &cfg->hc_listen, hl_next) {
 692                                         if (strcmp(nlst->hl_addr,
 693                                             clst->hl_addr) == 0) {
 694                                                 break;
 695                                         }
 696                                 }
 697                                 if (clst == NULL || clst->hl_conn == NULL)
 698                                         proto_close(nlst->hl_conn);
 699                         }
 700                         TAILQ_REMOVE(&newcfg->hc_listen, nlst, hl_next);
 701                         free(nlst);
 702                 }
 703                 yy_config_free(newcfg);
 704         }
 705         if (newpfh != NULL)
 706                 (void)pidfile_remove(newpfh);
 707         pjdlog_warning("Configuration not reloaded.");
 708 }
 709
 710 static void
 711 terminate_workers(void)
 712 {
 713         struct hast_resource *res;
 714
 715         pjdlog_info("Termination signal received, exiting.");
 716         TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
 717                 if (res->hr_workerpid == 0)
 718                         continue;
 719                 pjdlog_info("Terminating worker process (resource=%s, role=%s, pid=%u).",
 720                     res->hr_name, role2str(res->hr_role), res->hr_workerpid);
 721                 if (kill(res->hr_workerpid, SIGTERM) == 0)
 722                         continue;
 723                 pjdlog_errno(LOG_WARNING,
 724                     "Unable to send signal to worker process (resource=%s, role=%s, pid=%u).",
 725                     res->hr_name, role2str(res->hr_role), res->hr_workerpid);
 726         }
 727 }
 728
 729 static void
 730 listen_accept(struct hastd_listen *lst)
 731 {
 732         struct hast_resource *res;
 733         struct proto_conn *conn;
 734         struct nv *nvin, *nvout, *nverr;
 735         const char *resname;
 736         const unsigned char *token;
 737         char laddr[256], raddr[256];
 738         size_t size;
 739         pid_t pid;
 740         int status;
 741
 742         proto_local_address(lst->hl_conn, laddr, sizeof(laddr));
 743         pjdlog_debug(1, "Accepting connection to %s.", laddr);
 744
 745         if (proto_accept(lst->hl_conn, &conn) < 0) {
 746                 pjdlog_errno(LOG_ERR, "Unable to accept connection %s", laddr);
 747                 return;
 748         }
 749
 750         proto_local_address(conn, laddr, sizeof(laddr));
 751         proto_remote_address(conn, raddr, sizeof(raddr));
 752         pjdlog_info("Connection from %s to %s.", raddr, laddr);
 753
 754         /* Error in setting timeout is not critical, but why should it fail? */
 755         if (proto_timeout(conn, HAST_TIMEOUT) < 0)
 756                 pjdlog_errno(LOG_WARNING, "Unable to set connection timeout");
 757
 758         nvin = nvout = nverr = NULL;
 759
 760         /*
 761          * Before receiving any data see if remote host have access to any
 762          * resource.
 763          */
 764         TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
 765                 if (proto_address_match(conn, res->hr_remoteaddr))
 766                         break;
 767         }
 768         if (res == NULL) {
 769                 pjdlog_error("Client %s isn't known.", raddr);
 770                 goto close;
 771         }
 772         /* Ok, remote host can access at least one resource. */
 773
 774         if (hast_proto_recv_hdr(conn, &nvin) < 0) {
 775                 pjdlog_errno(LOG_ERR, "Unable to receive header from %s",
 776                     raddr);
 777                 goto close;
 778         }
 779
 780         resname = nv_get_string(nvin, "resource");
 781         if (resname == NULL) {
 782                 pjdlog_error("No 'resource' field in the header received from %s.",
 783                     raddr);
 784                 goto close;
 785         }
 786         pjdlog_debug(2, "%s: resource=%s", raddr, resname);
 787         token = nv_get_uint8_array(nvin, &size, "token");
 788         /*
 789          * NULL token means that this is first conection.
 790          */
 791         if (token != NULL && size != sizeof(res->hr_token)) {
 792                 pjdlog_error("Received token of invalid size from %s (expected %zu, got %zu).",
 793                     raddr, sizeof(res->hr_token), size);
 794                 goto close;
 795         }
 796
 797         /*
 798          * From now on we want to send errors to the remote node.
 799          */
 800         nverr = nv_alloc();
 801
 802         /* Find resource related to this connection. */
 803         TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
 804                 if (strcmp(resname, res->hr_name) == 0)
 805                         break;
 806         }
 807         /* Have we found the resource? */
 808         if (res == NULL) {
 809                 pjdlog_error("No resource '%s' as requested by %s.",
 810                     resname, raddr);
 811                 nv_add_stringf(nverr, "errmsg", "Resource not configured.");
 812                 goto fail;
 813         }
 814
 815         /* Now that we know resource name setup log prefix. */
 816         pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
 817
 818         /* Does the remote host have access to this resource? */
 819         if (!proto_address_match(conn, res->hr_remoteaddr)) {
 820                 pjdlog_error("Client %s has no access to the resource.", raddr);
 821                 nv_add_stringf(nverr, "errmsg", "No access to the resource.");
 822                 goto fail;
 823         }
 824         /* Is the resource marked as secondary? */
 825         if (res->hr_role != HAST_ROLE_SECONDARY) {
 826                 pjdlog_warning("We act as %s for the resource and not as %s as requested by %s.",
 827                     role2str(res->hr_role), role2str(HAST_ROLE_SECONDARY),
 828                     raddr);
 829                 nv_add_stringf(nverr, "errmsg",
 830                     "Remote node acts as %s for the resource and not as %s.",
 831                     role2str(res->hr_role), role2str(HAST_ROLE_SECONDARY));
 832                 if (res->hr_role == HAST_ROLE_PRIMARY) {
 833                         /*
 834                          * If we act as primary request the other side to wait
 835                          * for us a bit, as we might be finishing cleanups.
 836                          */
 837                         nv_add_uint8(nverr, 1, "wait");
 838                 }
 839                 goto fail;
 840         }
 841         /* Does token (if exists) match? */
 842         if (token != NULL && memcmp(token, res->hr_token,
 843             sizeof(res->hr_token)) != 0) {
 844                 pjdlog_error("Token received from %s doesn't match.", raddr);
 845                 nv_add_stringf(nverr, "errmsg", "Token doesn't match.");
 846                 goto fail;
 847         }
 848         /*
 849          * If there is no token, but we have half-open connection
 850          * (only remotein) or full connection (worker process is running)
 851          * we have to cancel those and accept the new connection.
 852          */
 853         if (token == NULL) {
 854                 PJDLOG_ASSERT(res->hr_remoteout == NULL);
 855                 pjdlog_debug(1, "Initial connection from %s.", raddr);
 856                 if (res->hr_workerpid != 0) {
 857                         PJDLOG_ASSERT(res->hr_remotein == NULL);
 858                         pjdlog_debug(1,
 859                             "Worker process exists (pid=%u), stopping it.",
 860                             (unsigned int)res->hr_workerpid);
 861                         /* Stop child process. */
 862                         if (kill(res->hr_workerpid, SIGINT) < 0) {
 863                                 pjdlog_errno(LOG_ERR,
 864                                     "Unable to stop worker process (pid=%u)",
 865                                     (unsigned int)res->hr_workerpid);
 866                                 /*
 867                                  * Other than logging the problem we
 868                                  * ignore it - nothing smart to do.
 869                                  */
 870                         }
 871                         /* Wait for it to exit. */
 872                         else if ((pid = waitpid(res->hr_workerpid,
 873                             &status, 0)) != res->hr_workerpid) {
 874                                 /* We can only log the problem. */
 875                                 pjdlog_errno(LOG_ERR,
 876                                     "Waiting for worker process (pid=%u) failed",
 877                                     (unsigned int)res->hr_workerpid);
 878                         } else {
 879                                 child_exit_log(res->hr_workerpid, status);
 880                         }
 881                         child_cleanup(res);
 882                 } else if (res->hr_remotein != NULL) {
 883                         char oaddr[256];
 884
 885                         proto_remote_address(res->hr_remotein, oaddr,
 886                             sizeof(oaddr));
 887                         pjdlog_debug(1,
 888                             "Canceling half-open connection from %s on connection from %s.",
 889                             oaddr, raddr);
 890                         proto_close(res->hr_remotein);
 891                         res->hr_remotein = NULL;
 892                 }
 893         }
 894
 895         /*
 896          * Checks and cleanups are done.
 897          */
 898
 899         if (token == NULL) {
 900                 arc4random_buf(res->hr_token, sizeof(res->hr_token));
 901                 nvout = nv_alloc();
 902                 nv_add_uint8_array(nvout, res->hr_token,
 903                     sizeof(res->hr_token), "token");
 904                 if (nv_error(nvout) != 0) {
 905                         pjdlog_common(LOG_ERR, 0, nv_error(nvout),
 906                             "Unable to prepare return header for %s", raddr);
 907                         nv_add_stringf(nverr, "errmsg",
 908                             "Remote node was unable to prepare return header: %s.",
 909                             strerror(nv_error(nvout)));
 910                         goto fail;
 911                 }
 912                 if (hast_proto_send(NULL, conn, nvout, NULL, 0) < 0) {
 913                         int error = errno;
 914
 915                         pjdlog_errno(LOG_ERR, "Unable to send response to %s",
 916                             raddr);
 917                         nv_add_stringf(nverr, "errmsg",
 918                             "Remote node was unable to send response: %s.",
 919                             strerror(error));
 920                         goto fail;
 921                 }
 922                 res->hr_remotein = conn;
 923                 pjdlog_debug(1, "Incoming connection from %s configured.",
 924                     raddr);
 925         } else {
 926                 res->hr_remoteout = conn;
 927                 pjdlog_debug(1, "Outgoing connection to %s configured.", raddr);
 928                 hastd_secondary(res, nvin);
 929         }
 930         nv_free(nvin);
 931         nv_free(nvout);
 932         nv_free(nverr);
 933         pjdlog_prefix_set("%s", "");
 934         return;
 935 fail:
 936         if (nv_error(nverr) != 0) {
 937                 pjdlog_common(LOG_ERR, 0, nv_error(nverr),
 938                     "Unable to prepare error header for %s", raddr);
 939                 goto close;
 940         }
 941         if (hast_proto_send(NULL, conn, nverr, NULL, 0) < 0) {
 942                 pjdlog_errno(LOG_ERR, "Unable to send error to %s", raddr);
 943                 goto close;
 944         }
 945 close:
 946         if (nvin != NULL)
 947                 nv_free(nvin);
 948         if (nvout != NULL)
 949                 nv_free(nvout);
 950         if (nverr != NULL)
 951                 nv_free(nverr);
 952         proto_close(conn);
 953         pjdlog_prefix_set("%s", "");
 954 }
 955
 956 static void
 957 connection_migrate(struct hast_resource *res)
 958 {
 959         struct proto_conn *conn;
 960         int16_t val = 0;
 961
 962         pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
 963
 964         PJDLOG_ASSERT(res->hr_role == HAST_ROLE_PRIMARY);
 965
 966         if (proto_recv(res->hr_conn, &val, sizeof(val)) < 0) {
 967                 pjdlog_errno(LOG_WARNING,
 968                     "Unable to receive connection command");
 969                 return;
 970         }
 971         if (proto_client(res->hr_sourceaddr[0] != '\0' ? res->hr_sourceaddr : NULL,
 972             res->hr_remoteaddr, &conn) < 0) {
 973                 val = errno;
 974                 pjdlog_errno(LOG_WARNING,
 975                     "Unable to create outgoing connection to %s",
 976                     res->hr_remoteaddr);
 977                 goto out;
 978         }
 979         if (proto_connect(conn, -1) < 0) {
 980                 val = errno;
 981                 pjdlog_errno(LOG_WARNING, "Unable to connect to %s",
 982                     res->hr_remoteaddr);
 983                 proto_close(conn);
 984                 goto out;
 985         }
 986         val = 0;
 987 out:
 988         if (proto_send(res->hr_conn, &val, sizeof(val)) < 0) {
 989                 pjdlog_errno(LOG_WARNING,
 990                     "Unable to send reply to connection request");
 991         }
 992         if (val == 0 && proto_connection_send(res->hr_conn, conn) < 0)
 993                 pjdlog_errno(LOG_WARNING, "Unable to send connection");
 994
 995         pjdlog_prefix_set("%s", "");
 996 }
 997
 998 static void
 999 check_signals(void)
1000 {
1001         struct timespec sigtimeout;
1002         sigset_t mask;
1003         int signo;
1004
1005         sigtimeout.tv_sec = 0;
1006         sigtimeout.tv_nsec = 0;
1007
1008         PJDLOG_VERIFY(sigemptyset(&mask) == 0);
1009         PJDLOG_VERIFY(sigaddset(&mask, SIGHUP) == 0);
1010         PJDLOG_VERIFY(sigaddset(&mask, SIGINT) == 0);
1011         PJDLOG_VERIFY(sigaddset(&mask, SIGTERM) == 0);
1012         PJDLOG_VERIFY(sigaddset(&mask, SIGCHLD) == 0);
1013
1014         while ((signo = sigtimedwait(&mask, NULL, &sigtimeout)) != -1) {
1015                 switch (signo) {
1016                 case SIGINT:
1017                 case SIGTERM:
1018                         sigexit_received = true;
1019                         terminate_workers();
1020                         proto_close(cfg->hc_controlconn);
1021                         exit(EX_OK);
1022                         break;
1023                 case SIGCHLD:
1024                         child_exit();
1025                         break;
1026                 case SIGHUP:
1027                         hastd_reload();
1028                         break;
1029                 default:
1030                         PJDLOG_ABORT("Unexpected signal (%d).", signo);
1031                 }
1032         }
1033 }
1034
1035 static void
1036 main_loop(void)
1037 {
1038         struct hast_resource *res;
1039         struct hastd_listen *lst;
1040         struct timeval seltimeout;
1041         int fd, maxfd, ret;
1042         time_t lastcheck, now;
1043         fd_set rfds;
1044
1045         lastcheck = time(NULL);
1046         seltimeout.tv_sec = REPORT_INTERVAL;
1047         seltimeout.tv_usec = 0;
1048
1049         for (;;) {
1050                 check_signals();
1051
1052                 /* Setup descriptors for select(2). */
1053                 FD_ZERO(&rfds);
1054                 maxfd = fd = proto_descriptor(cfg->hc_controlconn);
1055                 PJDLOG_ASSERT(fd >= 0);
1056                 FD_SET(fd, &rfds);
1057                 TAILQ_FOREACH(lst, &cfg->hc_listen, hl_next) {
1058                         if (lst->hl_conn == NULL)
1059                                 continue;
1060                         fd = proto_descriptor(lst->hl_conn);
1061                         PJDLOG_ASSERT(fd >= 0);
1062                         FD_SET(fd, &rfds);
1063                         maxfd = fd > maxfd ? fd : maxfd;
1064                 }
1065                 TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
1066                         if (res->hr_event == NULL)
1067                                 continue;
1068                         fd = proto_descriptor(res->hr_event);
1069                         PJDLOG_ASSERT(fd >= 0);
1070                         FD_SET(fd, &rfds);
1071                         maxfd = fd > maxfd ? fd : maxfd;
1072                         if (res->hr_role == HAST_ROLE_PRIMARY) {
1073                                 /* Only primary workers asks for connections. */
1074                                 PJDLOG_ASSERT(res->hr_conn != NULL);
1075                                 fd = proto_descriptor(res->hr_conn);
1076                                 PJDLOG_ASSERT(fd >= 0);
1077                                 FD_SET(fd, &rfds);
1078                                 maxfd = fd > maxfd ? fd : maxfd;
1079                         } else {
1080                                 PJDLOG_ASSERT(res->hr_conn == NULL);
1081                         }
1082                 }
1083
1084                 PJDLOG_ASSERT(maxfd + 1 <= (int)FD_SETSIZE);
1085                 ret = select(maxfd + 1, &rfds, NULL, NULL, &seltimeout);
1086                 now = time(NULL);
1087                 if (lastcheck + REPORT_INTERVAL <= now) {
1088                         hook_check();
1089                         lastcheck = now;
1090                 }
1091                 if (ret == 0) {
1092                         /*
1093                          * select(2) timed out, so there should be no
1094                          * descriptors to check.
1095                          */
1096                         continue;
1097                 } else if (ret == -1) {
1098                         if (errno == EINTR)
1099                                 continue;
1100                         KEEP_ERRNO((void)pidfile_remove(pfh));
1101                         pjdlog_exit(EX_OSERR, "select() failed");
1102                 }
1103
1104                 /*
1105                  * Check for signals before we do anything to update our
1106                  * info about terminated workers in the meantime.
1107                  */
1108                 check_signals();
1109
1110                 if (FD_ISSET(proto_descriptor(cfg->hc_controlconn), &rfds))
1111                         control_handle(cfg);
1112                 TAILQ_FOREACH(lst, &cfg->hc_listen, hl_next) {
1113                         if (lst->hl_conn == NULL)
1114                                 continue;
1115                         if (FD_ISSET(proto_descriptor(lst->hl_conn), &rfds))
1116                                 listen_accept(lst);
1117                 }
1118                 TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
1119                         if (res->hr_event == NULL)
1120                                 continue;
1121                         if (FD_ISSET(proto_descriptor(res->hr_event), &rfds)) {
1122                                 if (event_recv(res) == 0)
1123                                         continue;
1124                                 /* The worker process exited? */
1125                                 proto_close(res->hr_event);
1126                                 res->hr_event = NULL;
1127                                 if (res->hr_conn != NULL) {
1128                                         proto_close(res->hr_conn);
1129                                         res->hr_conn = NULL;
1130                                 }
1131                                 continue;
1132                         }
1133                         if (res->hr_role == HAST_ROLE_PRIMARY) {
1134                                 PJDLOG_ASSERT(res->hr_conn != NULL);
1135                                 if (FD_ISSET(proto_descriptor(res->hr_conn),
1136                                     &rfds)) {
1137                                         connection_migrate(res);
1138                                 }
1139                         } else {
1140                                 PJDLOG_ASSERT(res->hr_conn == NULL);
1141                         }
1142                 }
1143         }
1144 }
1145
1146 static void
1147 dummy_sighandler(int sig __unused)
1148 {
1149         /* Nothing to do. */
1150 }
1151
1152 int
1153 main(int argc, char *argv[])
1154 {
1155         struct hastd_listen *lst;
1156         const char *pidfile;
1157         pid_t otherpid;
1158         bool foreground;
1159         int debuglevel;
1160         sigset_t mask;
1161
1162         foreground = false;
1163         debuglevel = 0;
1164         pidfile = NULL;
1165
1166         for (;;) {
1167                 int ch;
1168
1169                 ch = getopt(argc, argv, "c:dFhP:");
1170                 if (ch == -1)
1171                         break;
1172                 switch (ch) {
1173                 case 'c':
1174                         cfgpath = optarg;
1175                         break;
1176                 case 'd':
1177                         debuglevel++;
1178                         break;
1179                 case 'F':
1180                         foreground = true;
1181                         break;
1182                 case 'P':
1183                         pidfile = optarg;
1184                         break;
1185                 case 'h':
1186                 default:
1187                         usage();
1188                 }
1189         }
1190         argc -= optind;
1191         argv += optind;
1192
1193         pjdlog_init(PJDLOG_MODE_STD);
1194         pjdlog_debug_set(debuglevel);
1195
1196         g_gate_load();
1197
1198         /*
1199          * When path to the configuration file is relative, obtain full path,
1200          * so we can always find the file, even after daemonizing and changing
1201          * working directory to /.
1202          */
1203         if (cfgpath[0] != '/') {
1204                 const char *newcfgpath;
1205
1206                 newcfgpath = realpath(cfgpath, NULL);
1207                 if (newcfgpath == NULL) {
1208                         pjdlog_exit(EX_CONFIG,
1209                             "Unable to obtain full path of %s", cfgpath);
1210                 }
1211                 cfgpath = newcfgpath;
1212         }
1213
1214         cfg = yy_config_parse(cfgpath, true);
1215         PJDLOG_ASSERT(cfg != NULL);
1216
1217         if (pidfile != NULL) {
1218                 if (strlcpy(cfg->hc_pidfile, pidfile,
1219                     sizeof(cfg->hc_pidfile)) >= sizeof(cfg->hc_pidfile)) {
1220                         pjdlog_exitx(EX_CONFIG, "Pidfile path is too long.");
1221                 }
1222         }
1223         pfh = pidfile_open(cfg->hc_pidfile, 0600, &otherpid);
1224         if (pfh == NULL) {
1225                 if (errno == EEXIST) {
1226                         pjdlog_exitx(EX_TEMPFAIL,
1227                             "Another hastd is already running, pidfile: %s, pid: %jd.",
1228                             cfg->hc_pidfile, (intmax_t)otherpid);
1229                 }
1230                 /* If we cannot create pidfile for other reasons, only warn. */
1231                 pjdlog_errno(LOG_WARNING, "Unable to open or create pidfile %s",
1232                     cfg->hc_pidfile);
1233         }
1234
1235         /*
1236          * Restore default actions for interesting signals in case parent
1237          * process (like init(8)) decided to ignore some of them (like SIGHUP).
1238          */
1239         PJDLOG_VERIFY(signal(SIGHUP, SIG_DFL) != SIG_ERR);
1240         PJDLOG_VERIFY(signal(SIGINT, SIG_DFL) != SIG_ERR);
1241         PJDLOG_VERIFY(signal(SIGTERM, SIG_DFL) != SIG_ERR);
1242         /*
1243          * Because SIGCHLD is ignored by default, setup dummy handler for it,
1244          * so we can mask it.
1245          */
1246         PJDLOG_VERIFY(signal(SIGCHLD, dummy_sighandler) != SIG_ERR);
1247
1248         PJDLOG_VERIFY(sigemptyset(&mask) == 0);
1249         PJDLOG_VERIFY(sigaddset(&mask, SIGHUP) == 0);
1250         PJDLOG_VERIFY(sigaddset(&mask, SIGINT) == 0);
1251         PJDLOG_VERIFY(sigaddset(&mask, SIGTERM) == 0);
1252         PJDLOG_VERIFY(sigaddset(&mask, SIGCHLD) == 0);
1253         PJDLOG_VERIFY(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
1254
1255         /* Listen on control address. */
1256         if (proto_server(cfg->hc_controladdr, &cfg->hc_controlconn) < 0) {
1257                 KEEP_ERRNO((void)pidfile_remove(pfh));
1258                 pjdlog_exit(EX_OSERR, "Unable to listen on control address %s",
1259                     cfg->hc_controladdr);
1260         }
1261         /* Listen for remote connections. */
1262         TAILQ_FOREACH(lst, &cfg->hc_listen, hl_next) {
1263                 if (proto_server(lst->hl_addr, &lst->hl_conn) < 0) {
1264                         KEEP_ERRNO((void)pidfile_remove(pfh));
1265                         pjdlog_exit(EX_OSERR, "Unable to listen on address %s",
1266                             lst->hl_addr);
1267                 }
1268         }
1269
1270         if (!foreground) {
1271                 if (daemon(0, 0) < 0) {
1272                         KEEP_ERRNO((void)pidfile_remove(pfh));
1273                         pjdlog_exit(EX_OSERR, "Unable to daemonize");
1274                 }
1275
1276                 /* Start logging to syslog. */
1277                 pjdlog_mode_set(PJDLOG_MODE_SYSLOG);
1278
1279                 /* Write PID to a file. */
1280                 if (pidfile_write(pfh) < 0) {
1281                         pjdlog_errno(LOG_WARNING,
1282                             "Unable to write PID to a file %s",
1283                             cfg->hc_pidfile);
1284                 } else {
1285                         pjdlog_debug(1, "PID stored in %s.", cfg->hc_pidfile);
1286                 }
1287         }
1288
1289         pjdlog_info("Started successfully, running protocol version %d.",
1290             HAST_PROTO_VERSION);
1291
1292         pjdlog_debug(1, "Listening on control address %s.",
1293             cfg->hc_controladdr);
1294         TAILQ_FOREACH(lst, &cfg->hc_listen, hl_next)
1295                 pjdlog_info("Listening on address %s.", lst->hl_addr);
1296
1297         hook_init();
1298
1299         main_loop();
1300
1301         exit(0);
1302 }