external/bsd/ntp/dist/ntpsnmpd/netsnmp_daemonize.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * system.c
   5  */
   6 /* Portions of this file are subject to the following copyright(s).  See
   7  * the Net-SNMP's COPYING file for more details and other copyrights
   8  * that may apply:
   9  */
  10 /***********************************************************
  11         Copyright 1992 by Carnegie Mellon University
  12
  13                       All Rights Reserved
  14
  15 Permission to use, copy, modify, and distribute this software and its
  16 documentation for any purpose and without fee is hereby granted,
  17 provided that the above copyright notice appear in all copies and that
  18 both that copyright notice and this permission notice appear in
  19 supporting documentation, and that the name of CMU not be
  20 used in advertising or publicity pertaining to distribution of the
  21 software without specific, written prior permission.
  22
  23 CMU DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
  24 ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
  25 CMU BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
  26 ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
  27 WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
  28 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  29 SOFTWARE.
  30 ******************************************************************/
  31 /*
  32  * Portions of this file are copyrighted by:
  33  * Copyright © 2003 Sun Microsystems, Inc. All rights reserved.
  34  * Use is subject to license terms specified in the COPYING file
  35  * distributed with the Net-SNMP package.
  36  */
  37 /*
  38  * System dependent routines go here
  39  */
  40 #include <net-snmp/net-snmp-config.h>
  41 #undef PACKAGE_BUGREPORT
  42 #undef PACKAGE_NAME
  43 #undef PACKAGE_STRING
  44 #undef PACKAGE_TARNAME
  45 #undef PACKAGE_VERSION
  46 #include <config.h>
  47
  48 #ifdef NEED_NETSNMP_DAEMONIZE
  49
  50 #include <stdio.h>
  51 #include <ctype.h>
  52 #include <errno.h>
  53
  54 #if HAVE_UNISTD_H
  55 #include <unistd.h>
  56 #endif
  57 #if HAVE_STDLIB_H
  58 #include <stdlib.h>
  59 #endif
  60
  61 #if TIME_WITH_SYS_TIME
  62 # ifdef WIN32
  63 #  include <sys/timeb.h>
  64 # else
  65 #  include <sys/time.h>
  66 # endif
  67 # include <time.h>
  68 #else
  69 # if HAVE_SYS_TIME_H
  70 #  include <sys/time.h>
  71 # else
  72 #  include <time.h>
  73 # endif
  74 #endif
  75
  76 #include <sys/types.h>
  77
  78 #if HAVE_NETINET_IN_H
  79 #include <netinet/in.h>
  80 #endif
  81
  82 #if HAVE_WINSOCK_H
  83 #include <winsock.h>
  84 #endif
  85 #if HAVE_SYS_SOCKET_H
  86 #include <sys/socket.h>
  87 #endif
  88 #if HAVE_NET_IF_H
  89 #include <net/if.h>
  90 #endif
  91
  92 #if HAVE_SYS_SOCKIO_H
  93 #include <sys/sockio.h>
  94 #endif
  95
  96 #if HAVE_SYS_IOCTL_H
  97 #include <sys/ioctl.h>
  98 #endif
  99
 100 #ifdef HAVE_NLIST_H
 101 #include <nlist.h>
 102 #endif
 103
 104 #if HAVE_SYS_FILE_H
 105 #include <sys/file.h>
 106 #endif
 107
 108 #if HAVE_KSTAT_H
 109 #include <kstat.h>
 110 #endif
 111
 112 #if HAVE_SYS_PARAM_H
 113 #include <sys/param.h>
 114 #endif
 115 #if HAVE_SYS_SYSCTL_H
 116 #include <sys/sysctl.h>
 117 #endif
 118
 119 #if HAVE_STRING_H
 120 #include <string.h>
 121 #else
 122 #include <strings.h>
 123 #endif
 124
 125 #if HAVE_DMALLOC_H
 126 #include <dmalloc.h>
 127 #endif
 128
 129 #ifdef HAVE_SYS_STAT_H
 130 #include <sys/stat.h>
 131 #endif
 132 #if HAVE_FCNTL_H
 133 #include <fcntl.h>
 134 #endif
 135
 136 #if defined(hpux10) || defined(hpux11)
 137 #include <sys/pstat.h>
 138 #endif
 139
 140 #if HAVE_SYS_UTSNAME_H
 141 #include <sys/utsname.h>
 142 #endif
 143
 144 #if HAVE_SYS_SYSTEMCFG_H
 145 #include <sys/systemcfg.h>
 146 #endif
 147
 148 #if HAVE_SYS_SYSTEMINFO_H
 149 #include <sys/systeminfo.h>
 150 #endif
 151
 152 #include <net-snmp/types.h>
 153 #include <net-snmp/output_api.h>
 154 #include <net-snmp/utilities.h>
 155 #include <net-snmp/library/system.h>    /* for "internal" definitions */
 156
 157 #include <net-snmp/library/snmp_api.h>
 158 #include <net-snmp/library/read_config.h> /* for get_temp_file_pattern() */
 159
 160 #ifndef IFF_LOOPBACK
 161 #       define IFF_LOOPBACK 0
 162 #endif
 163
 164 #ifdef  INADDR_LOOPBACK
 165 # define LOOPBACK    INADDR_LOOPBACK
 166 #else
 167 # define LOOPBACK    0x7f000001
 168 #endif
 169
 170 /**
 171  * fork current process into the background.
 172  *
 173  * This function forks a process into the background, in order to
 174  * become a daemon process. It does a few things along the way:
 175  *
 176  * - becoming a process/session group leader, and  forking a second time so
 177  *   that process/session group leader can exit.
 178  *
 179  * - changing the working directory to /
 180  *
 181  * - closing stdin, stdout and stderr (unless stderr_log is set) and
 182  *   redirecting them to /dev/null
 183  *
 184  * @param quit_immediately : indicates if the parent process should
 185  *                           exit after a successful fork.
 186  * @param stderr_log       : indicates if stderr is being used for
 187  *                           logging and shouldn't be closed
 188  * @returns -1 : fork error
 189  *           0 : child process returning
 190  *          >0 : parent process returning. returned value is the child PID.
 191  */
 192 int
 193 netsnmp_daemonize(int quit_immediately, int stderr_log)
 194 {
 195     int i = 0;
 196     DEBUGMSGT(("daemonize","deamonizing...\n"));
 197 #if HAVE_FORK
 198     /*
 199      * Fork to return control to the invoking process and to
 200      * guarantee that we aren't a process group leader.
 201      */
 202     i = fork();
 203     if (i != 0) {
 204         /* Parent. */
 205         DEBUGMSGT(("daemonize","first fork returned %d.\n", i));
 206         if(i == -1) {
 207             snmp_log(LOG_ERR,"first fork failed (errno %d) in "
 208                      "netsnmp_daemonize()\n", errno);
 209             return -1;
 210         }
 211         if (quit_immediately) {
 212             DEBUGMSGT(("daemonize","parent exiting\n"));
 213             exit(0);
 214         }
 215     } else {
 216         /* Child. */
 217 #ifdef HAVE_SETSID
 218         /* Become a process/session group leader. */
 219         setsid();
 220 #endif
 221         /*
 222          * Fork to let the process/session group leader exit.
 223          */
 224         if ((i = fork()) != 0) {
 225             DEBUGMSGT(("daemonize","second fork returned %d.\n", i));
 226             if(i == -1) {
 227                 snmp_log(LOG_ERR,"second fork failed (errno %d) in "
 228                          "netsnmp_daemonize()\n", errno);
 229             }
 230             /* Parent. */
 231             exit(0);
 232         }
 233 #ifndef WIN32
 234         else {
 235             /* Child. */
 236
 237             DEBUGMSGT(("daemonize","child continuing\n"));
 238
 239             /* Avoid keeping any directory in use. */
 240             chdir("/");
 241
 242             if (!stderr_log) {
 243                 /*
 244                  * Close inherited file descriptors to avoid
 245                  * keeping unnecessary references.
 246                  */
 247                 close(0);
 248                 close(1);
 249                 close(2);
 250
 251                 /*
 252                  * Redirect std{in,out,err} to /dev/null, just in
 253                  * case.
 254                  */
 255                 open("/dev/null", O_RDWR);
 256                 dup(0);
 257                 dup(0);
 258             }
 259         }
 260 #endif /* !WIN32 */
 261     }
 262 #endif /* HAVE_FORK */
 263     return i;
 264 }
 265
 266 #else /* !NEED_NETSNMP_DAEMONIZE */
 267 int netsnp_daemonize_bs;
 268 #endif