dabbad/dabbad.c

   1 /**
   2  * \file dabbad.c
   3  * \author written by Emmanuel Roullit emmanuel.roullit@gmail.com (c) 2012
   4  * \date 2012
   5  */
   6
   7 /* __LICENSE_HEADER_BEGIN__ */
   8
   9 /*
  10  * Copyright (C) 2012   Emmanuel Roullit <emmanuel.roullit@gmail.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or (at
  15  * your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  19  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  20  * for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License along
  23  * with this program; if not, write to the Free Software Foundation, Inc.,
  24  * 51 Franklin St, Fifth Floor, Boston, MA 02110, USA
  25  *
  26  */
  27
  28 /* __LICENSE_HEADER_END__ */
  29
  30 /*
  31
  32 =head1 NAME
  33
  34 dabbad - Multithreaded packet mmap daemon
  35
  36 =head1 SYNOPSIS
  37
  38 dabbad [--daemonize][--help]
  39
  40 =head1 DESCRIPTION
  41
  42 dabbad (dabba daemon) is here to manage multithreaded network captures.
  43 It listens an IPC interface and waits for commands to execute.
  44
  45 =head1 EXAMPLES
  46
  47 =over
  48
  49 =item dabbad
  50
  51 Start dabbad in a classic process mode. It allows the user to
  52 see debug messages.
  53
  54 =item dabbad --daemonize
  55
  56 Start dabbad as a daemon.
  57
  58 =item dabbad --help
  59
  60 Prints help content.
  61
  62 =back
  63
  64 =head1 AUTHOR
  65
  66 Written by Emmanuel Roullit <emmanuel.roullit@gmail.com>
  67
  68 =head1 BUGS
  69
  70 =over
  71
  72 =item Please report bugs to <https://github.com/eroullit/dabba/issues>
  73
  74 =item dabba project project page: <https://github.com/eroullit/dabba>
  75
  76 =back
  77
  78 =head1 COPYRIGHT
  79
  80 =over
  81
  82 =item Copyright © 2012 Emmanuel Roullit.
  83
  84 =item License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>.
  85
  86 =item This is free software: you are free to change and redistribute it.
  87
  88 =item There is NO WARRANTY, to the extent permitted by law.
  89
  90 =back
  91
  92 =cut
  93
  94 */
  95
  96 #include <stdio.h>
  97 #include <stdlib.h>
  98 #include <errno.h>
  99 #include <unistd.h>
 100 #include <assert.h>
 101 #include <getopt.h>
 102 #include <sys/types.h>
 103 #include <sys/stat.h>
 104 #include <fcntl.h>
 105
 106 #include <dabbad/ipc.h>
 107 #include <dabbad/help.h>
 108
 109 enum dabbad_opts {
 110         OPT_DAEMONIZE,
 111         OPT_HELP
 112 };
 113
 114 /**
 115  * \brief Dabbad options getter
 116  * \return Dabbad option data structure
 117  */
 118
 119 const struct option *dabbad_options_get(void)
 120 {
 121         static const struct option dabbad_long_options[] = {
 122                 {"daemonize", no_argument, NULL, OPT_DAEMONIZE},
 123                 {"help", no_argument, NULL, OPT_HELP},
 124                 {NULL, 0, NULL, 0}
 125         };
 126
 127         return (dabbad_long_options);
 128 }
 129
 130 /**
 131  * \internal
 132  * \brief Create dabbad pidfile
 133  * \return 0 on success, else on failure.
 134  *
 135  * This function creates start time a file containing dabbad process id.
 136  */
 137
 138 static inline int dabbad_pidfile_create(void)
 139 {
 140         int rc = EIO;
 141         int pidfd = -1;
 142         char pidstr[8] = { 0 };
 143         ssize_t pidstrlen = 0;
 144
 145         pidfd = creat(DABBAD_PID_FILE, 0600);
 146
 147         if (pidfd < 0)
 148                 return errno;
 149
 150         pidstrlen = snprintf(pidstr, sizeof(pidstr), "%i\n", getpid());
 151
 152         if (write(pidfd, pidstr, pidstrlen) != pidstrlen) {
 153                 rc = EIO;
 154         }
 155
 156         close(pidfd);
 157         return rc;
 158 }
 159
 160 /**
 161  * \brief Dabbad entry point
 162  * \param[in]       argc                Argument counter
 163  * \param[in]       argv                Argument vector
 164  * \return 0 on success, else on failure
 165  *
 166  * This function is dabbad entry point.
 167  * It parses given arguments, configure the daemon accordingly and start
 168  * IPC message polling.
 169  */
 170
 171 int main(int argc, char **argv)
 172 {
 173         int opt, opt_idx;
 174         int daemonize = 0;
 175
 176         assert(argc);
 177         assert(argv);
 178
 179         while ((opt =
 180                 getopt_long_only(argc, argv, "", dabbad_options_get(),
 181                                  &opt_idx)) != EOF) {
 182                 switch (opt) {
 183                 case OPT_DAEMONIZE:
 184                         daemonize = 1;
 185                         break;
 186                 case OPT_HELP:
 187                 default:
 188                         show_usage(dabbad_options_get());
 189                         return EXIT_SUCCESS;
 190                         break;
 191
 192                 }
 193         }
 194
 195         if (daemonize) {
 196                 if (daemon(-1, 0)) {
 197                         perror("Could not daemonize process");
 198                         return errno;
 199                 }
 200         }
 201
 202         assert(dabbad_pidfile_create());
 203         dabbad_ipc_msg_init();
 204
 205         return dabbad_ipc_msg_poll();
 206 }