--- /dev/null
+/*
+ process.c -- process management functions
+ Copyright (C) 1999-2002 Ivo Timmermans <itimmermans@bigfoot.com>,
+ 2000-2002 Guus Sliepen <guus@sliepen.warande.net>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ $Id: process.c,v 1.1 2002/04/28 12:46:26 zarq Exp $
+*/
+
+#include "config.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <string.h>
+#include <syslog.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <termios.h>
+
+#include <pidfile.h>
+#include <utils.h>
+#include <xalloc.h>
+
+#include "conf.h"
+#include "interface.h"
+#include "process.h"
+#include "subnet.h"
+#include "connection.h"
+#include "logging.h"
+
+#include "system.h"
+
+/* If zero, don't detach from the terminal. */
+int do_detach = 1;
+
+extern char *identname;
+extern char *pidfilename;
+extern char **g_argv;
+
+sigset_t emptysigset;
+
+static int saved_debug_lvl = 0;
+
+extern int sighup;
+extern int sigalrm;
+extern int do_purge;
+
+void memory_full(int size)
+{
+ log(0, TLOG_ERROR,
+ _("Memory exhausted (couldn't allocate %d bytes), exitting."),
+ size);
+ cp_trace();
+ exit(1);
+}
+
+/* Some functions the less gifted operating systems might lack... */
+
+#ifndef HAVE_FCLOSEALL
+int fcloseall(void)
+{
+ fflush(stdin);
+ fflush(stdout);
+ fflush(stderr);
+ fclose(stdin);
+ fclose(stdout);
+ fclose(stderr);
+ return 0;
+}
+#endif
+
+/*
+ Close network connections, and terminate neatly
+*/
+void cleanup_and_exit(int c)
+{
+cp
+ close_network_connections();
+
+ syslog(LOG_NOTICE, _("Terminating"));
+
+ closelog();
+ exit(c);
+}
+
+/*
+ check for an existing tinc for this net, and write pid to pidfile
+*/
+int write_pidfile(void)
+{
+ int pid;
+cp
+ if((pid = check_pid(pidfilename)))
+ {
+ if(netname)
+ fprintf(stderr, _("A tincd is already running for net `%s' with pid %d.\n"),
+ netname, pid);
+ else
+ fprintf(stderr, _("A tincd is already running with pid %d.\n"), pid);
+ return 1;
+ }
+
+ /* if it's locked, write-protected, or whatever */
+ if(!write_pid(pidfilename))
+ return 1;
+cp
+ return 0;
+}
+
+/*
+ kill older tincd for this net
+*/
+int kill_other(int signal)
+{
+ int pid;
+cp
+ if(!(pid = read_pid(pidfilename)))
+ {
+ if(netname)
+ fprintf(stderr, _("No other tincd is running for net `%s'.\n"), netname);
+ else
+ fprintf(stderr, _("No other tincd is running.\n"));
+ return 1;
+ }
+
+ errno = 0; /* No error, sometimes errno is only changed on error */
+ /* ESRCH is returned when no process with that pid is found */
+ if(kill(pid, signal) && errno == ESRCH)
+ {
+ if(netname)
+ fprintf(stderr, _("The tincd for net `%s' is no longer running. "), netname);
+ else
+ fprintf(stderr, _("The tincd is no longer running. "));
+
+ fprintf(stderr, _("Removing stale lock file.\n"));
+ remove_pid(pidfilename);
+ }
+cp
+ return 0;
+}
+
+/*
+ Detach from current terminal, write pidfile, kill parent
+*/
+int detach(void)
+{
+cp
+ setup_signals();
+
+ /* First check if we can open a fresh new pidfile */
+
+ if(write_pidfile())
+ return -1;
+
+ /* If we succeeded in doing that, detach */
+
+ closelog();
+
+ if(do_detach)
+ {
+ if(daemon(0, 0) < 0)
+ {
+ fprintf(stderr, _("Couldn't detach from terminal: %s"), strerror(errno));
+ return -1;
+ }
+
+ /* Now UPDATE the pid in the pidfile, because we changed it... */
+
+ if(!write_pid(pidfilename))
+ return -1;
+ }
+
+ openlog(identname, LOG_CONS | LOG_PID, LOG_DAEMON);
+
+ if(debug_lvl > DEBUG_NOTHING)
+ log(0, TLOG_NOTICE,
+ _("tincd %s (%s %s) starting, debug level %d"),
+ VERSION, __DATE__, __TIME__, debug_lvl);
+ else
+ log(DEBUG_NOTHING, TLOG_NOTICE,
+ _("tincd %s starting"),
+ VERSION);
+
+ xalloc_fail_func = memory_full;
+cp
+ return 0;
+}
+
+/*
+ Execute the program name, with sane environment. All output will be
+ redirected to syslog.
+*/
+void _execute_script(const char *name) __attribute__ ((noreturn));
+void _execute_script(const char *name)
+{
+ char *scriptname;
+ char *s;
+cp
+#ifdef HAVE_UNSETENV
+ unsetenv("NETNAME");
+ unsetenv("INTERFACE");
+#endif
+
+ if(netname)
+ {
+ asprintf(&s, "NETNAME=%s", netname);
+ putenv(s); /* Don't free s! see man 3 putenv */
+ }
+
+ chdir("/");
+
+ asprintf(&scriptname, "%s/%s", confbase, name);
+
+ /* Close all file descriptors */
+ closelog(); /* <- this means we cannot use syslog() here anymore! */
+ fcloseall();
+
+ execl(scriptname, NULL);
+ /* No return on success */
+
+ if(errno != ENOENT) /* Ignore if the file does not exist */
+ exit(1); /* Some error while trying execl(). */
+ else
+ exit(0);
+}
+
+/*
+ Fork and execute the program pointed to by name.
+*/
+int execute_script(const char *name)
+{
+ pid_t pid;
+ int status;
+cp
+ if((pid = fork()) < 0)
+ {
+ syslog(LOG_ERR, _("System call `%s' failed: %s"), "fork", strerror(errno));
+ return -1;
+ }
+
+ if(pid)
+ {
+ log(DEBUG_STATUS, TLOG_INFO,
+ _("Executing script %s"),
+ name);
+
+ if(waitpid(pid, &status, 0) == pid)
+ {
+ if(WIFEXITED(status)) /* Child exited by itself */
+ {
+ if(WEXITSTATUS(status))
+ {
+ syslog(LOG_ERR, _("Process %d (%s) exited with non-zero status %d"), pid, name, WEXITSTATUS(status));
+ return -1;
+ }
+ else
+ return 0;
+ }
+ else if(WIFSIGNALED(status)) /* Child was killed by a signal */
+ {
+ syslog(LOG_ERR, _("Process %d (%s) was killed by signal %d (%s)"),
+ pid, name, WTERMSIG(status), strsignal(WTERMSIG(status)));
+ return -1;
+ }
+ else /* Something strange happened */
+ {
+ syslog(LOG_ERR, _("Process %d (%s) terminated abnormally"), pid, name);
+ return -1;
+ }
+ }
+ else
+ {
+ syslog(LOG_ERR, _("System call `%s' failed: %s"), "waitpid", strerror(errno));
+ return -1;
+ }
+ }
+cp
+ /* Child here */
+
+ _execute_script(name);
+}
+
+
+/*
+ Signal handlers.
+*/
+
+RETSIGTYPE
+sigterm_handler(int a)
+{
+ log(DEBUG_NOTHING, TLOG_NOTICE,
+ _("Got TERM signal"));
+
+ cleanup_and_exit(0);
+}
+
+RETSIGTYPE
+sigquit_handler(int a)
+{
+ log(DEBUG_NOTHING, TLOG_NOTICE,
+ _("Got QUIT signal"));
+ cleanup_and_exit(0);
+}
+
+RETSIGTYPE
+fatal_signal_square(int a)
+{
+ syslog(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a, strsignal(a));
+ cp_trace();
+ exit(1);
+}
+
+RETSIGTYPE
+fatal_signal_handler(int a)
+{
+ syslog(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a));
+ cp_trace();
+
+ syslog(LOG_NOTICE, _("Not restarting."));
+ exit(1);
+}
+
+RETSIGTYPE
+sighup_handler(int a)
+{
+ if(debug_lvl > DEBUG_NOTHING)
+ syslog(LOG_NOTICE, _("Got HUP signal"));
+ sighup = 1;
+}
+
+RETSIGTYPE
+sigint_handler(int a)
+{
+ if(saved_debug_lvl)
+ {
+ syslog(LOG_NOTICE, _("Reverting to old debug level (%d)"),
+ saved_debug_lvl);
+ debug_lvl = saved_debug_lvl;
+ saved_debug_lvl = 0;
+ }
+ else
+ {
+ syslog(LOG_NOTICE, _("Temporarily setting debug level to 5. Kill me with SIGINT again to go back to level %d."),
+ debug_lvl);
+ saved_debug_lvl = debug_lvl;
+ debug_lvl = 5;
+ }
+}
+
+RETSIGTYPE
+sigalrm_handler(int a)
+{
+ if(debug_lvl > DEBUG_NOTHING)
+ syslog(LOG_NOTICE, _("Got ALRM signal"));
+ sigalrm = 1;
+}
+
+RETSIGTYPE
+sigusr1_handler(int a)
+{
+ dump_connections();
+}
+
+RETSIGTYPE
+sigusr2_handler(int a)
+{
+ dump_nodes();
+ dump_edges();
+ dump_subnets();
+}
+
+RETSIGTYPE
+sigwinch_handler(int a)
+{
+ extern int do_purge;
+ do_purge = 1;
+}
+
+RETSIGTYPE
+unexpected_signal_handler(int a)
+{
+ syslog(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a));
+ cp_trace();
+}
+
+RETSIGTYPE
+ignore_signal_handler(int a)
+{
+ if(debug_lvl >= DEBUG_SCARY_THINGS)
+ {
+ syslog(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a));
+ cp_trace();
+ }
+}
+
+struct {
+ int signal;
+ void (*handler)(int);
+} sighandlers[] = {
+ { SIGHUP, sighup_handler },
+ { SIGTERM, sigterm_handler },
+ { SIGQUIT, sigquit_handler },
+ { SIGSEGV, fatal_signal_handler },
+ { SIGBUS, fatal_signal_handler },
+ { SIGILL, fatal_signal_handler },
+ { SIGPIPE, ignore_signal_handler },
+ { SIGINT, sigint_handler },
+ { SIGUSR1, sigusr1_handler },
+ { SIGUSR2, sigusr2_handler },
+ { SIGCHLD, ignore_signal_handler },
+ { SIGALRM, sigalrm_handler },
+ { SIGWINCH, sigwinch_handler },
+ { 0, NULL }
+};
+
+void
+setup_signals(void)
+{
+ int i;
+ struct sigaction act;
+
+ sigemptyset(&emptysigset);
+ act.sa_handler = NULL;
+ act.sa_mask = emptysigset;
+ act.sa_flags = 0;
+
+ /* Set a default signal handler for every signal, errors will be
+ ignored. */
+ for(i = 0; i < NSIG; i++)
+ {
+ if(!do_detach)
+ act.sa_handler = SIG_DFL;
+ else
+ act.sa_handler = unexpected_signal_handler;
+ sigaction(i, &act, NULL);
+ }
+
+ /* If we didn't detach, allow coredumps */
+ if(!do_detach)
+ sighandlers[3].handler = SIG_DFL;
+
+ /* Then, for each known signal that we want to catch, assign a
+ handler to the signal, with error checking this time. */
+ for(i = 0; sighandlers[i].signal; i++)
+ {
+ act.sa_handler = sighandlers[i].handler;
+ if(sigaction(sighandlers[i].signal, &act, NULL) < 0)
+ fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"),
+ sighandlers[i].signal, strsignal(sighandlers[i].signal), strerror(errno));
+ }
+}
projects / tinc / blobdiff