src/tools/sysdbd/main.c

   1 /*
   2  * SysDB - src/tools/sysdbd/main.c
   3  * Copyright (C) 2012 Sebastian 'tokkee' Harl <sh@tokkee.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  16  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  17  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  18  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
  19  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #if HAVE_CONFIG_H
  29 #       include "config.h"
  30 #endif /* HAVE_CONFIG_H */
  31
  32 #include "sysdb.h"
  33 #include "core/plugin.h"
  34 #include "core/store.h"
  35 #include "utils/error.h"
  36
  37 #include "frontend/connection.h"
  38 #include "frontend/sock.h"
  39
  40 #include "tools/sysdbd/configfile.h"
  41
  42 #if HAVE_LIBGEN_H
  43 #       include <libgen.h>
  44 #else /* HAVE_LIBGEN_H */
  45 #       define basename(path) (path)
  46 #endif /* ! HAVE_LIBGEN_H */
  47
  48 #include <errno.h>
  49
  50 #include <sys/stat.h>
  51 #include <fcntl.h>
  52
  53 #include <signal.h>
  54
  55 #include <stdio.h>
  56 #include <stdlib.h>
  57 #include <string.h>
  58
  59 #include <unistd.h>
  60
  61 #include <pthread.h>
  62
  63 #ifndef CONFIGFILE
  64 #       define CONFIGFILE SYSCONFDIR"/sysdb/sysdbd.conf"
  65 #endif
  66
  67 #ifndef DEFAULT_SOCKET
  68 #       define DEFAULT_SOCKET "unix:"LOCALSTATEDIR"/run/sysdbd.sock"
  69 #endif
  70
  71 static sdb_plugin_loop_t plugin_main_loop = SDB_PLUGIN_LOOP_INIT;
  72 static sdb_fe_loop_t frontend_main_loop = SDB_FE_LOOP_INIT;
  73
  74 static char *config_filename = NULL;
  75 static int reconfigure = 0;
  76
  77 static char *default_listen_addresses[] = {
  78         DEFAULT_SOCKET,
  79 };
  80
  81 static void
  82 sigintterm_handler(int __attribute__((unused)) signo)
  83 {
  84         frontend_main_loop.do_loop = 0;
  85 } /* sigintterm_handler */
  86
  87 static void
  88 sighup_handler(int __attribute__((unused)) signo)
  89 {
  90         /* (temporarily) terminate the plugin loop ... */
  91         frontend_main_loop.do_loop = 0;
  92         /* ... and tell the main loop to reconfigure the daemon */
  93         reconfigure = 1;
  94 } /* sighup_handler */
  95
  96 static void
  97 exit_usage(char *name, int status)
  98 {
  99         printf(
 100 "Usage: %s <options>\n"
 101
 102 "\nOptions:\n"
 103 "  -C FILE   the main configuration file\n"
 104 "            default: "CONFIGFILE"\n"
 105 "  -D        do not run in background (daemonize)\n"
 106 "\n"
 107 "  -h        display this help and exit\n"
 108 "  -V        display the version number and copyright\n"
 109
 110 "\nSysDB daemon "SDB_VERSION_STRING SDB_VERSION_EXTRA", "PACKAGE_URL"\n",
 111 basename(name));
 112         exit(status);
 113 } /* exit_usage */
 114
 115 static void
 116 exit_version(void)
 117 {
 118         printf("SysDBd version "SDB_VERSION_STRING SDB_VERSION_EXTRA", "
 119                         "built "BUILD_DATE"\n"
 120                         "using libsysdb version %s%s\n"
 121                         "Copyright (C) 2012-2014 "PACKAGE_MAINTAINER"\n"
 122
 123                         "\nThis is free software under the terms of the BSD license, see "
 124                         "the source for\ncopying conditions. There is NO WARRANTY; not "
 125                         "even for MERCHANTABILITY or\nFITNESS FOR A PARTICULAR "
 126                         "PURPOSE.\n", sdb_version_string(), sdb_version_extra());
 127         exit(0);
 128 } /* exit_version */
 129
 130 static int
 131 daemonize(void)
 132 {
 133         pid_t pid;
 134
 135         if ((pid = fork()) < 0) {
 136                 char errbuf[1024];
 137                 sdb_log(SDB_LOG_ERR, "Failed to fork to background: %s",
 138                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 139                 return errno;
 140         }
 141         else if (pid != 0) {
 142                 /* parent */
 143                 exit(0);
 144         }
 145
 146         if (chdir("/")) {
 147                 char errbuf[1024];
 148                 sdb_log(SDB_LOG_ERR, "Failed to change working directory to "
 149                                 "the root directory: %s",
 150                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 151                 return errno;
 152         }
 153
 154         /* detach from session */
 155         setsid();
 156
 157         close(0);
 158         if (open("/dev/null", O_RDWR)) {
 159                 char errbuf[1024];
 160                 sdb_log(SDB_LOG_ERR, "Failed to connect stdin to '/dev/null': %s",
 161                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 162                 return errno;
 163         }
 164
 165         close(1);
 166         if (dup(0) != 1) {
 167                 char errbuf[1024];
 168                 sdb_log(SDB_LOG_ERR, "Could not connect stdout to '/dev/null': %s",
 169                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 170                 return errno;
 171         }
 172
 173         close(2);
 174         if (dup(0) != 2) {
 175                 char errbuf[1024];
 176                 sdb_log(SDB_LOG_ERR, "Could not connect stderr to '/dev/null': %s",
 177                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 178                 return errno;
 179         }
 180         return 0;
 181 } /* daemonize */
 182
 183 static int
 184 configure(void)
 185 {
 186         int status;
 187
 188         if ((status = daemon_parse_config(config_filename))) {
 189                 if (status > 0)
 190                         sdb_log(SDB_LOG_ERR, "Failed to parse configuration file.");
 191                 else
 192                         sdb_log(SDB_LOG_ERR, "Failed to load configuration file.\n"
 193                                         "\tCheck other error messages for details.");
 194                 return 1;
 195         }
 196
 197         if (! listen_addresses) {
 198                 listen_addresses = default_listen_addresses;
 199                 listen_addresses_num = SDB_STATIC_ARRAY_LEN(default_listen_addresses);
 200         }
 201         return 0;
 202 } /* configure */
 203
 204 static int
 205 do_reconfigure(void)
 206 {
 207         int status;
 208
 209         sdb_log(SDB_LOG_INFO, "Reconfiguring SysDB daemon");
 210
 211         if (listen_addresses != default_listen_addresses)
 212                 daemon_free_listen_addresses();
 213         listen_addresses = NULL;
 214
 215         sdb_plugin_reconfigure_init();
 216         if ((status = configure()))
 217                 return status;
 218         sdb_plugin_init_all();
 219         sdb_plugin_reconfigure_finish();
 220         sdb_connection_enable_logging();
 221         return 0;
 222 } /* do_reconfigure */
 223
 224 static void *
 225 backend_handler(void __attribute__((unused)) *data)
 226 {
 227         sdb_plugin_collector_loop(&plugin_main_loop);
 228         sdb_log(SDB_LOG_INFO, "Shutting down backend thread");
 229         return NULL;
 230 } /* backend_handler */
 231
 232 static int
 233 main_loop(void)
 234 {
 235         sdb_fe_socket_t *sock = sdb_fe_sock_create();
 236
 237         pthread_t backend_thread;
 238
 239         while (42) {
 240                 size_t i;
 241
 242                 plugin_main_loop.do_loop = 1;
 243                 frontend_main_loop.do_loop = 1;
 244
 245                 memset(&backend_thread, 0, sizeof(backend_thread));
 246                 if (pthread_create(&backend_thread, /* attr = */ NULL,
 247                                         backend_handler, /* arg = */ NULL)) {
 248                         char buf[1024];
 249                         sdb_log(SDB_LOG_ERR, "Failed to create backend handler thread: %s",
 250                                         sdb_strerror(errno, buf, sizeof(buf)));
 251
 252                         plugin_main_loop.do_loop = 0;
 253                         break;
 254                 }
 255
 256                 for (i = 0; i < listen_addresses_num; ++i)
 257                         if (sdb_fe_sock_add_listener(sock, listen_addresses[i]))
 258                                 break;
 259
 260                 /* break on error */
 261                 if (i >= listen_addresses_num)
 262                         sdb_fe_sock_listen_and_serve(sock, &frontend_main_loop);
 263
 264                 sdb_log(SDB_LOG_INFO, "Waiting for backend thread to terminate");
 265                 plugin_main_loop.do_loop = 0;
 266                 /* send a signal to interrupt the sleep call
 267                  * and make the thread shut down faster */
 268                 pthread_kill(backend_thread, SIGINT);
 269                 pthread_join(backend_thread, NULL);
 270
 271                 if (! reconfigure)
 272                         break;
 273
 274                 reconfigure = 0;
 275                 sdb_fe_sock_clear_listeners(sock);
 276                 if (do_reconfigure()) {
 277                         sdb_log(SDB_LOG_ERR, "Reconfiguration failed");
 278                         break;
 279                 }
 280         }
 281
 282         sdb_fe_sock_destroy(sock);
 283         return 0;
 284 } /* main_loop */
 285
 286 int
 287 main(int argc, char **argv)
 288 {
 289         _Bool do_daemonize = 1;
 290
 291         struct sigaction sa_intterm;
 292         struct sigaction sa_hup;
 293         int status;
 294
 295         sdb_error_set_logger(sdb_plugin_log);
 296
 297         while (42) {
 298                 int opt = getopt(argc, argv, "C:DhV");
 299
 300                 if (-1 == opt)
 301                         break;
 302
 303                 switch (opt) {
 304                         case 'C':
 305                                 config_filename = optarg;
 306                                 break;
 307                         case 'D':
 308                                 do_daemonize = 0;
 309                                 break;
 310
 311                         case 'h':
 312                                 exit_usage(argv[0], 0);
 313                                 break;
 314                         case 'V':
 315                                 exit_version();
 316                                 break;
 317                         default:
 318                                 exit_usage(argv[0], 1);
 319                 }
 320         }
 321
 322         if (optind < argc)
 323                 exit_usage(argv[0], 1);
 324
 325         if (! config_filename)
 326                 config_filename = CONFIGFILE;
 327         if ((status = configure()))
 328                 exit(status);
 329
 330         memset(&sa_intterm, 0, sizeof(sa_intterm));
 331         sa_intterm.sa_handler = sigintterm_handler;
 332         sa_intterm.sa_flags = 0;
 333
 334         if (sigaction(SIGINT, &sa_intterm, /* old action */ NULL)) {
 335                 char errbuf[1024];
 336                 sdb_log(SDB_LOG_ERR, "Failed to install signal handler for "
 337                                 "SIGINT: %s", sdb_strerror(errno, errbuf, sizeof(errbuf)));
 338                 exit(1);
 339         }
 340         if (sigaction(SIGTERM, &sa_intterm, /* old action */ NULL)) {
 341                 char errbuf[1024];
 342                 sdb_log(SDB_LOG_ERR, "Failed to install signal handler for "
 343                                 "SIGTERM: %s", sdb_strerror(errno, errbuf, sizeof(errbuf)));
 344                 exit(1);
 345         }
 346
 347         if (do_daemonize)
 348                 if (daemonize())
 349                         exit(1);
 350
 351         sdb_log(SDB_LOG_INFO, "SysDB daemon "SDB_VERSION_STRING
 352                         SDB_VERSION_EXTRA " (pid %i) initialized successfully",
 353                         (int)getpid());
 354
 355         sdb_plugin_init_all();
 356         plugin_main_loop.default_interval = SECS_TO_SDB_TIME(60);
 357
 358         memset(&sa_hup, 0, sizeof(sa_hup));
 359         sa_hup.sa_handler = sighup_handler;
 360         sa_hup.sa_flags = 0;
 361
 362         if (sigaction(SIGHUP, &sa_hup, /* old action */ NULL)) {
 363                 char errbuf[1024];
 364                 sdb_log(SDB_LOG_ERR, "Failed to install signal handler for "
 365                                 "SIGHUP: %s", sdb_strerror(errno, errbuf, sizeof(errbuf)));
 366                 exit(1);
 367         }
 368
 369         /* ignore, we see this, for example, if a client disconnects without
 370          * closing the connection cleanly */
 371         signal(SIGPIPE, SIG_IGN);
 372
 373         sdb_connection_enable_logging();
 374         status = main_loop();
 375
 376         sdb_log(SDB_LOG_INFO, "Shutting down SysDB daemon "SDB_VERSION_STRING
 377                         SDB_VERSION_EXTRA" (pid %i)", (int)getpid());
 378         sdb_plugin_shutdown_all();
 379         return status;
 380 } /* main */
 381
 382 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 383