src/daemon/syscollectord.c

   1 /*
   2  * syscollector - src/syscollecord.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 "syscollector.h"
  33 #include "core/plugin.h"
  34 #include "core/store.h"
  35 #include "utils/string.h"
  36
  37 #include "daemon/config.h"
  38
  39 #if HAVE_LIBGEN_H
  40 #       include <libgen.h>
  41 #else /* HAVE_LIBGEN_H */
  42 #       define basename(path) (path)
  43 #endif /* ! HAVE_LIBGEN_H */
  44
  45 #include <errno.h>
  46
  47 #include <sys/stat.h>
  48 #include <fcntl.h>
  49
  50 #include <signal.h>
  51
  52 #include <stdio.h>
  53 #include <stdlib.h>
  54 #include <string.h>
  55
  56 #include <unistd.h>
  57
  58 #ifndef CONFIGFILE
  59 #       define CONFIGFILE SYSCONFDIR"/syscollector/syscollectord.conf"
  60 #endif
  61
  62 static sc_plugin_loop_t plugin_main_loop = SC_PLUGIN_LOOP_INIT;
  63
  64 static void
  65 sigintterm_handler(int __attribute__((unused)) signo)
  66 {
  67         plugin_main_loop.do_loop = 0;
  68 } /* sigintterm_handler */
  69
  70 static void
  71 exit_usage(char *name, int status)
  72 {
  73         printf(
  74 "Usage: %s <options>\n"
  75
  76 "\nOptions:\n"
  77 "  -C FILE   the main configuration file\n"
  78 "            default: "CONFIGFILE"\n"
  79 "  -d        run in background (daemonize)\n"
  80 "\n"
  81 "  -h        display this help and exit\n"
  82 "  -V        display the version number and copyright\n"
  83
  84 "\nsyscollectord "SC_VERSION_STRING SC_VERSION_EXTRA", "PACKAGE_URL"\n",
  85 basename(name));
  86         exit(status);
  87 } /* exit_usage */
  88
  89 static void
  90 exit_version(void)
  91 {
  92         printf("syscollectord version "SC_VERSION_STRING SC_VERSION_EXTRA", "
  93                         "built "BUILD_DATE"\n"
  94                         "using libsyscollection verion %s%s\n"
  95                         "Copyright (C) 2012 "PACKAGE_MAINTAINER"\n"
  96
  97                         "\nThis is free software under the terms of the BSD license, see "
  98                         "the source for\ncopying conditions. There is NO WARRANTY; not "
  99                         "even for MERCHANTABILITY or\nFITNESS FOR A PARTICULAR "
 100                         "PURPOSE.\n", sc_version_string(), sc_version_extra());
 101         exit(0);
 102 } /* exit_version */
 103
 104 static int
 105 daemonize(void)
 106 {
 107         pid_t pid;
 108
 109         if ((pid = fork()) < 0) {
 110                 char errbuf[1024];
 111                 fprintf(stderr, "Failed to fork to background: %s\n",
 112                                 sc_strerror(errno, errbuf, sizeof(errbuf)));
 113                 return errno;
 114         }
 115         else if (pid != 0) {
 116                 /* parent */
 117                 exit(0);
 118         }
 119
 120         if (chdir("/")) {
 121                 char errbuf[1024];
 122                 fprintf(stderr, "Failed to change working directory to /: %s\n",
 123                                 sc_strerror(errno, errbuf, sizeof(errbuf)));
 124                 return errno;
 125         }
 126
 127         /* detach from session */
 128         setsid();
 129
 130         close(0);
 131         if (open("/dev/null", O_RDWR)) {
 132                 char errbuf[1024];
 133                 fprintf(stderr, "Failed to connect stdin to '/dev/null': %s\n",
 134                                 sc_strerror(errno, errbuf, sizeof(errbuf)));
 135                 return errno;
 136         }
 137
 138         close(1);
 139         if (dup(0) != 1) {
 140                 char errbuf[1024];
 141                 fprintf(stderr, "Could not connect stdout to '/dev/null': %s\n",
 142                                 sc_strerror(errno, errbuf, sizeof(errbuf)));
 143                 return errno;
 144         }
 145
 146         close(2);
 147         if (dup(0) != 2) {
 148                 char errbuf[1024];
 149                 fprintf(stdout, "Could not connect stderr to '/dev/null': %s\n",
 150                                 sc_strerror(errno, errbuf, sizeof(errbuf)));
 151                 return errno;
 152         }
 153         return 0;
 154 } /* daemonize */
 155
 156 int
 157 main(int argc, char **argv)
 158 {
 159         char *config_filename = NULL;
 160         _Bool daemon = 0;
 161
 162         struct sigaction sa_intterm;
 163
 164         while (42) {
 165                 int opt = getopt(argc, argv, "C:dhV");
 166
 167                 if (-1 == opt)
 168                         break;
 169
 170                 switch (opt) {
 171                         case 'C':
 172                                 config_filename = optarg;
 173                                 break;
 174                         case 'd':
 175                                 daemon = 1;
 176                                 break;
 177
 178                         case 'h':
 179                                 exit_usage(argv[0], 0);
 180                                 break;
 181                         case 'V':
 182                                 exit_version();
 183                                 break;
 184                         default:
 185                                 exit_usage(argv[0], 1);
 186                 }
 187         }
 188
 189         if (optind < argc)
 190                 exit_usage(argv[0], 1);
 191
 192         if (! config_filename)
 193                 config_filename = CONFIGFILE;
 194
 195         if (daemon_parse_config(config_filename)) {
 196                 fprintf(stderr, "Failed to parse configuration file.\n");
 197                 exit(1);
 198         }
 199
 200         memset(&sa_intterm, 0, sizeof(sa_intterm));
 201         sa_intterm.sa_handler = sigintterm_handler;
 202         sa_intterm.sa_flags = 0;
 203
 204         if (sigaction(SIGINT, &sa_intterm, /* old action */ NULL)) {
 205                 char errbuf[1024];
 206                 fprintf(stderr, "Failed to install signal handler for SIGINT: %s\n",
 207                                 sc_strerror(errno, errbuf, sizeof(errbuf)));
 208                 exit(1);
 209         }
 210         if (sigaction(SIGTERM, &sa_intterm, /* old action */ NULL)) {
 211                 char errbuf[1024];
 212                 fprintf(stderr, "Failed to install signal handler for SIGTERM: %s\n",
 213                                 sc_strerror(errno, errbuf, sizeof(errbuf)));
 214                 exit(1);
 215         }
 216
 217         if (daemon)
 218                 if (daemonize())
 219                         exit(1);
 220
 221         fprintf(stderr, "syscollectord "SC_VERSION_STRING" (pid %i) "
 222                         "initialized successfully\n", (int)getpid());
 223
 224         sc_plugin_init_all();
 225         sc_plugin_collector_loop(&plugin_main_loop);
 226
 227         fprintf(stderr, "Shutting down syscollector "SC_VERSION_STRING
 228                         " (pid %i)\n", (int)getpid());
 229
 230         fprintf(stderr, "Store dump:\n");
 231         sc_store_dump(stderr);
 232         return 0;
 233 } /* main */
 234
 235 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 236