void StartThreads( void )
{
    pthread_mutex_t     spinLockMutex;
    pid_t               childPid;
    struct sigaction    sa;
    sigset_t            sigmsk;
    size_t              len;
    ThreadCallback_t    callbacks;

    GlobalAbort = FALSE;

#ifndef __CYGWIN__
    len = confstr( _CS_GNU_LIBPTHREAD_VERSION, NULL, 0 );
    if( len ) {
        pthreadsVersion = CREATEN(char, len);
        confstr( _CS_GNU_LIBPTHREAD_VERSION, pthreadsVersion, len );
    }
#else
    (void)len;
    pthreadsVersion = memstrlink( "Cygwin" );
#endif

    if( !pthreadsVersion || strstr( pthreadsVersion, "linuxthreads" ) ) {
        fprintf( stderr, "havokmud requires NPTL to operate correctly.\n\n"
                         "The signal handling in linuxthreads is just too "
                         "broken to use.\n\n" );
        exit( 1 );
    }

    /* Do we need to detach? */
    if( Daemon ) {
        childPid = fork();
        if( childPid < 0 ) {
            perror( "Couldn't detach in daemon mode" );
            _exit( 1 );
        }

        if( childPid != 0 ) {
            /* This is still the parent, report the child's pid and exit */
            printf( "[Detached as PID %d]\n", childPid );
            /* And exit the parent */
            _exit( 0 );
        }

        /* After this is in the detached child */

        /* Close stdin, stdout, stderr to release the tty */
        close(0);
        close(1);
        close(2);
    }

    LoggingQ      = QueueCreate( 1024 );
    ConnectInputQ = QueueCreate( 256 );
    ConnectDnsQ   = QueueCreate( 64 );
    InputLoginQ   = QueueCreate( 256 );
    InputEditorQ  = QueueCreate( 256 );
    InputPlayerQ  = QueueCreate( 256 );
    InputImmortQ  = QueueCreate( 256 );
    MailQ         = QueueCreate( 128 );
    QueryQ        = QueueCreate( 1024 );
    ProtobufQ     = QueueCreate( 1024 );

    mainThreadId = pthread_self();
    /* 
     * Setup the sigmasks for this thread (which is the parent to all others).
     * This will propogate to all children.
     */
    sigfillset( &sigmsk );
    sigdelset( &sigmsk, SIGUSR1 );
    sigdelset( &sigmsk, SIGUSR2 );
    sigdelset( &sigmsk, SIGHUP );
    sigdelset( &sigmsk, SIGWINCH );
    sigdelset( &sigmsk, SIGINT );
    sigdelset( &sigmsk, SIGSEGV );
    sigdelset( &sigmsk, SIGILL );
    sigdelset( &sigmsk, SIGFPE );
    pthread_sigmask( SIG_SETMASK, &sigmsk, NULL );

    memset( &callbacks, 0, sizeof(ThreadCallback_t) );
    callbacks.sighupFunc = mainSighup;
    thread_register( &mainThreadId, "MainThread", NULL );

    /* Setup signal handler for SIGUSR1 (toggles Debug) */
    sa.sa_sigaction = (sigAction_t)logging_toggle_debug;
    sigemptyset( &sa.sa_mask );
    sa.sa_flags = SA_RESTART;
    sigaction( SIGUSR1, &sa, NULL );

    /* Setup the exit handler */
    atexit( MainDelayExit );

    /* Setup signal handler for SIGINT (shut down cleanly) */
    sa.sa_sigaction = (sigAction_t)signal_interrupt;
    sigemptyset( &sa.sa_mask );
    sa.sa_flags = SA_RESTART;
    sigaction( SIGINT, &sa, NULL );
    
    /* Setup signal handlers that are to be propogated to all threads */
    sa.sa_sigaction = (sigAction_t)signal_everyone;
//.........这里部分代码省略.........

int exec_cmd(command_t cmd)
{

    pid_t pid = fork();
	if(!pid)
    {
        if( strcmp(cmd.inputFile,"") )
        {          
            char string[MAX_COMMAND_LENGTH];
            FILE * file = fopen(cmd.inputFile, "r");

            while(fgets(string, MAX_COMMAND_LENGTH, file) != NULL)
            {
                char* args[MAX_PATH_LENGTH];

                size_t len = strlen(string);
                char last_char = string[len - 1];

                if (last_char == '\n' || last_char == '\r')
                {
                    string[len - 1] = '\0';
                    len = len - 1;
                }

                args[0] = cmd.execArgs[0];

                char * temp;
                temp = strtok(string," ");
                args[1] = temp;

                int i = 2;
                while(((temp = strtok(NULL," ")) != NULL) && (i<255))
                {
                    args[i] = temp;
                    i++;
                }
                args[i] = NULL;

                int pid2 = fork();
                if(!pid2)
                {
                    if(strcmp(cmd.outputFile,""))
                    {
                        execToFile(args, cmd.outputFile);
                    }
                    else
                    {
                        checkWkdir(cmd.execArgs[0]);
                        if(execvp(cmd.execArgs[0],args)<0)
                        {
                            fprintf(stderr, "Error execing %s. Error# %d\n",cmd.cmdstr, errno);
                            exit(EXIT_FAILURE);
                        }
                    }
                }
                else
                {
                    if((waitpid(pid2,&status,0))==-1)
                    {
                        fprintf(stderr, "Process encountered an error._3 ERROR%d", errno);
                        return EXIT_FAILURE;
                    }
                }
                
            }
            
        }
        else if (strcmp(cmd.outputFile,""))
        {
            execToFile(cmd.execArgs, cmd.outputFile);
        }
        else
        {
            // char * tmpstr[MAX_PATH_LENGTH];
            // strcpy(tmpstr,cmd.execArgs[0]);
            // printf("arg0: %s\n",cmd.execArgs[0]);
            // printf("tmpstr: %s\n",tmpstr);

            //if(execvp(tmpstr,cmd.execArgs)<0)
            checkWkdir(cmd.execArgs[0]);
            if(execvp(cmd.execArgs[0],cmd.execArgs)<0)
            {
                fprintf(stderr, "Error execing %s. Error# %d\n",cmd.cmdstr, errno);
                exit(EXIT_FAILURE);
            }
        }
        exit(0);
	}
    else
    {

        sigset_t tmpSa;
        sigfillset( &tmpSa);
        sigdelset(&tmpSa,SIGINT);
        sigdelset(&tmpSa,SIGTSTP);
        sigprocmask(SIG_SETMASK, &tmpSa, NULL);
        //Start blocking signals

        if(!cmd.execBg)
        {
//.........这里部分代码省略.........

bs_sig_t bs_sigready(bs_sig_t signum) {
  int out = sigismember(&ready, (int)signum);
  sigdelset(&ready, signum);
  return (bs_sig_t)out;
}

static int dpram_thread(void *data)
{
	int ret = 0;
	int i;
	struct file *filp;
	struct sched_param schedpar;

	dpram_task = current;

	daemonize("dpram_thread");
	strcpy(current->comm, "multipdp");

	schedpar.sched_priority = 1;
	sched_setscheduler(current, SCHED_FIFO, &schedpar);

	/* set signals to accept */
	siginitsetinv(&current->blocked, sigmask(SIGUSR1));
	recalc_sigpending();

	for (i = 0; i < 10; i++) {
	filp = dpram_open();
	if (filp == NULL) {
			EPRINTK("dpram_open failed! retry\n");
			msleep(1000);
		} else
			break;
	}
	if (filp == NULL) {
		EPRINTK("dpram_open failed!\n");
		goto out;
	}

	dpram_filp = filp;

	/* send start signal */
	complete(&dpram_complete);

	while (1) {
		ret = dpram_poll(filp);

		if (ret == -ERESTARTSYS) {
			if (sigismember(&current->pending.signal, SIGUSR1)) {
				sigdelset(&current->pending.signal, SIGUSR1);
				recalc_sigpending();
				ret = 0;
				break;
			}
		}
		
		else if (ret < 0) {
			EPRINTK("dpram_poll() failed\n");
			break;
		}
		
		else {
			char ch;
			ret = dpram_read(dpram_filp, &ch, sizeof(ch));

			if(ret < 0) {
				return ret;
			}

			if (ch == 0x7f) {
				pdp_demux();
			}
		}
	}

	dpram_close(filp);
	dpram_filp = NULL;

out:
	dpram_task = NULL;

	/* send finish signal and exit */
	complete_and_exit(&dpram_complete, ret);
}

/*****************************************************************************
 * main: parse command line, start interface and spawn threads.
 *****************************************************************************/
int main( int i_argc, const char *ppsz_argv[] )
{
    /* The so-called POSIX-compliant MacOS X reportedly processes SIGPIPE even
     * if it is blocked in all thread. Also some libraries want SIGPIPE blocked
     * as they have no clue about signal masks.
     * Note: this is NOT an excuse for not protecting against SIGPIPE. If
     * LibVLC runs outside of VLC, we cannot rely on this code snippet. */
    signal (SIGPIPE, SIG_IGN);
    /* Restore default for SIGCHLD in case parent ignores it. */
    signal (SIGCHLD, SIG_DFL);

#ifdef HAVE_SETENV
# ifndef NDEBUG
    /* Activate malloc checking routines to detect heap corruptions. */
    setenv ("MALLOC_CHECK_", "2", 1);

    /* Disable the ugly Gnome crash dialog so that we properly segfault */
    setenv ("GNOME_DISABLE_CRASH_DIALOG", "1", 1);
# endif

    /* Clear the X.Org startup notification ID. Otherwise the UI might try to
     * change the environment while the process is multi-threaded. That could
     * crash. Screw you X.Org. Next time write a thread-safe specification. */
    unsetenv ("DESKTOP_STARTUP_ID");
#endif

#ifndef ALLOW_RUN_AS_ROOT
    if (geteuid () == 0)
    {
        fprintf (stderr, "VLC is not supposed to be run as root. Sorry.\n"
        "If you need to use real-time priorities and/or privileged TCP ports\n"
        "you can use %s-wrapper (make sure it is Set-UID root and\n"
        "cannot be run by non-trusted users first).\n", ppsz_argv[0]);
        return 1;
    }
#endif

    setlocale (LC_ALL, "");

    if (isatty (STDERR_FILENO))
        /* This message clutters error logs. It is print it only on a TTY.
         * Forunately, LibVLC prints version infos with -vv anyhow. */
        fprintf (stderr, "VLC media player %s (revision %s)\n",
                 libvlc_get_version(), libvlc_get_changeset());

    /* Synchronously intercepted POSIX signals.
     *
     * In a threaded program such as VLC, the only sane way to handle signals
     * is to block them in all threads but one - this is the only way to
     * predict which thread will receive them. If any piece of code depends
     * on delivery of one of this signal it is intrinsically not thread-safe
     * and MUST NOT be used in VLC, whether we like it or not.
     * There is only one exception: if the signal is raised with
     * pthread_kill() - we do not use this in LibVLC but some pthread
     * implementations use them internally. You should really use conditions
     * for thread synchronization anyway.
     *
     * Signal that request a clean shutdown, and force an unclean shutdown
     * if they are triggered again 2+ seconds later.
     * We have to handle SIGTERM cleanly because of daemon mode.
     * Note that we set the signals after the vlc_create call. */
    static const int sigs[] = {
        SIGINT, SIGHUP, SIGQUIT, SIGTERM,
    /* Signals that cause a no-op:
     * - SIGPIPE might happen with sockets and would crash VLC. It MUST be
     *   blocked by any LibVLC-dependent application, not just VLC.
     * - SIGCHLD comes after exec*() (such as httpd CGI support) and must
     *   be dequeued to cleanup zombie processes.
     */
        SIGPIPE, SIGCHLD
    };

    sigset_t set;
    sigemptyset (&set);
    for (unsigned i = 0; i < sizeof (sigs) / sizeof (sigs[0]); i++)
        sigaddset (&set, sigs[i]);
#ifdef HAVE_MAEMO
    sigaddset (&set, SIGRTMIN);
    {
        struct sigaction act = { .sa_handler = dummy_handler, };
        sigaction (SIGRTMIN, &act, NULL);
    }
#endif

    /* Block all these signals */
    pthread_sigmask (SIG_BLOCK, &set, NULL);
    sigdelset (&set, SIGPIPE);
    sigdelset (&set, SIGCHLD);

    /* Note that FromLocale() can be used before libvlc is initialized */
    const char *argv[i_argc + 3];
    int argc = 0;

    argv[argc++] = "--no-ignore-config";
#ifdef TOP_BUILDDIR
    argv[argc++] = FromLocale ("--plugin-path="TOP_BUILDDIR"/modules");
#endif
//.........这里部分代码省略.........

int main (int argc, char *argv[])
{
	pthread_mutexattr_t mattr;
	pthread_condattr_t cattr;
	pthread_attr_t	pattr;
	int		i, policy, main_prio;
	void *		exit_status;
	sigset_t	mask;
	struct sigaction act;
	struct sched_param param;

	logfile = stdout;
 
	assert (pthread_getschedparam (pthread_self (), &policy, &param) == 0);
	main_prio = param.sched_priority;

	/* Setupt our signal mask. */
	sigfillset (&mask);
	sigdelset (&mask, SIGINT);
	sigprocmask (SIG_SETMASK, &mask, NULL);

	/* Install a signal handler for SIGINT */
	sigemptyset (&act.sa_mask);
	sigaddset (&act.sa_mask, SIGINT);
	act.sa_handler = sighandler;
	act.sa_flags = SA_RESTART;
	sigaction (SIGINT, &act, NULL);

	/* This test relies on the concurrency level being 1. */
	pthread_setconcurrency(1);

	/*
	 * Initialize the thread attribute.
	 */
	assert (pthread_attr_init (&pattr) == 0);
	assert (pthread_attr_setdetachstate (&pattr,
	    PTHREAD_CREATE_JOINABLE) == 0);

	/*
	 * Initialize and create the waiter and condvar mutexes.
	 */
	assert (pthread_mutexattr_init (&mattr) == 0);
	assert (pthread_mutex_init (&waiter_mutex, &mattr) == 0);
	assert (pthread_mutex_init (&cond_mutex, &mattr) == 0);

	/*
	 * Initialize and create a condition variable.
	 */
	assert (pthread_condattr_init (&cattr) == 0);
	assert (pthread_cond_init (&cond_var, &cattr) == 0);

	/* Create a pipe to catch the results of thread wakeups. */
	assert (pipe (pipefd) == 0);

#if defined(_LIBC_R_) && defined(DEBUG)
	assert (pthread_switch_add_np (kern_switch) == 0);
#endif

	/*
	 * Create the waiting threads.
	 */
	for (i = 0; i < NUM_THREADS; i++) {
		assert (pthread_cond_init (&states[i].cond_var, &cattr) == 0);
		states[i].id = (u_int8_t) i;  /* NUM_THREADS must be <= 256 */
		states[i].status = 0;
		states[i].cmd.cmd_id = CMD_NONE;
		states[i].flags = 0;	/* No flags yet. */
		assert (pthread_create (&states[i].tid, &pattr, waiter,
		    (void *) &states[i]) == 0);
		param.sched_priority = main_prio - 10 + i;
		states[i].priority = param.sched_priority;
		assert (pthread_setschedparam (states[i].tid, SCHED_OTHER,
		    &param) == 0);
#if defined(_LIBC_R_)
		{
			char buf[30];

			snprintf (buf, sizeof(buf), "waiter_%d", i);
			pthread_set_name_np (states[i].tid, buf);
		}
#endif
	}

	/* Allow the threads to start. */
	sleep (1);
	log_trace ("Done creating threads.\n");

	log ("\n");
	mutex_init_test ();
	log ("\n");
	mutex_destroy_test ();
	log ("\n");
	mutex_lock_test ();
	log ("\n");
	mutex_unlock_test ();
	log ("\n");
	queueing_order_test ();
	log ("\n");
	mutex_prioinherit_test ();
	log ("\n");
//.........这里部分代码省略.........

void OPENSSL_cpuid_setup(void)
	{
	char *e;
	struct sigaction	ill_oact,ill_act;
	sigset_t		oset;
	static int trigger=0;

	if (trigger) return;
	trigger=1;
 
	sigfillset(&all_masked);
	sigdelset(&all_masked,SIGILL);
	sigdelset(&all_masked,SIGTRAP);
#ifdef SIGEMT
	sigdelset(&all_masked,SIGEMT);
#endif
	sigdelset(&all_masked,SIGFPE);
	sigdelset(&all_masked,SIGBUS);
	sigdelset(&all_masked,SIGSEGV);

	if ((e=getenv("OPENSSL_ppccap")))
		{
		OPENSSL_ppccap_P=strtoul(e,NULL,0);
		return;
		}

	OPENSSL_ppccap_P = 0;

#if defined(_AIX)
	if (sizeof(size_t)==4)
		{
		struct utsname uts;
# if defined(_SC_AIX_KERNEL_BITMODE)
		if (sysconf(_SC_AIX_KERNEL_BITMODE)!=64)	return;
# endif
		if (uname(&uts)!=0 || atoi(uts.version)<6)	return;
		}
#endif

	memset(&ill_act,0,sizeof(ill_act));
	ill_act.sa_handler = ill_handler;
	ill_act.sa_mask    = all_masked;

	sigprocmask(SIG_SETMASK,&ill_act.sa_mask,&oset);
	sigaction(SIGILL,&ill_act,&ill_oact);

	if (sizeof(size_t)==4)
		{
#ifdef __linux
		struct utsname uts;
		if (uname(&uts)==0 && strcmp(uts.machine,"ppc64")==0)
#endif
		if (sigsetjmp(ill_jmp,1) == 0)
			{
			OPENSSL_ppc64_probe();
			OPENSSL_ppccap_P |= PPC_FPU64;
			}
		}
	else
		{
		/*
		 * Wanted code detecting POWER6 CPU and setting PPC_FPU64
		 */
		}

	if (sigsetjmp(ill_jmp,1) == 0)
		{
		OPENSSL_altivec_probe();
		OPENSSL_ppccap_P |= PPC_ALTIVEC;
		}

	sigaction (SIGILL,&ill_oact,NULL);
	sigprocmask(SIG_SETMASK,&oset,NULL);
	}

int AP_UnixApp::main(const char * szAppName, int argc, char ** argv)
{
    // This is a static function.	
	
	if (!g_thread_supported ())
		g_thread_init (NULL);	
    
    // initialize our application.
	int exit_status = 0;
	AP_UnixApp * pMyUnixApp = new AP_UnixApp(szAppName);

#ifdef WITH_CHAMPLAIN
    gtk_clutter_init (&argc, &argv);
#endif
    
	/* this brace is here to ensure that our local variables on the stack
	 * do not outlive the application object by giving them a lower scope
	 */
	{
		XAP_Args XArgs = XAP_Args(argc, argv);
		AP_Args Args = AP_Args(&XArgs, szAppName, pMyUnixApp);
#ifdef LOGFILE
		UT_String sLogFile = pMyUnixApp->getUserPrivateDirectory();
		sLogFile += "abiLogFile";
		logfile = fopen(sLogFile.c_str(),"a+");
		fprintf(logfile,"About to do gtk_set_locale \n");
		fprintf(logfile,"New logfile \n");
#endif
		// Step 1: Initialize GTK and create the APP.
		// hack needed to intialize gtk before ::initialize
		setlocale(LC_ALL, "");
		gboolean have_display = gtk_init_check(&argc, &argv);
#ifdef LOGFILE
		fprintf(logfile,"Got display %d \n",have_display);
		fprintf(logfile,"Really display %d \n",have_display);
#endif
		if (have_display > 0) {
			Args.addOptions(gtk_get_option_group(TRUE));
			Args.parseOptions();
		}
		else {
			// no display, but we still need to at least parse our own arguments, damnit, for --to, --to-png, and --print
			Args.addOptions(gtk_get_option_group(FALSE));
			Args.parseOptions();
		}

		// if the initialize fails, we don't have icons, fonts, etc.
		if (!pMyUnixApp->initialize(have_display))
		{
			delete pMyUnixApp;
			return -1;	// make this something standard?
		}
	
		// Setup signal handlers, primarily for segfault
		// If we segfaulted before here, we *really* blew it
		struct sigaction sa;
		sa.sa_handler = signalWrapper;
    
		sigfillset(&sa.sa_mask);  // We don't want to hear about other signals
		sigdelset(&sa.sa_mask, SIGABRT); // But we will call abort(), so we can't ignore that
#if defined (SA_NODEFER) && defined (SA_RESETHAND)
		sa.sa_flags = SA_NODEFER | SA_RESETHAND; // Don't handle nested signals
#else
		sa.sa_flags = 0;
#endif
    
		sigaction(SIGSEGV, &sa, NULL);
		sigaction(SIGBUS, &sa, NULL);
		sigaction(SIGILL, &sa, NULL);
		sigaction(SIGQUIT, &sa, NULL);
		sigaction(SIGFPE, &sa, NULL);

		// TODO: handle SIGABRT
	
		// Step 2: Handle all non-window args.
    
		bool windowlessArgsWereSuccessful = true;
		if (!Args.doWindowlessArgs(windowlessArgsWereSuccessful )) {
			delete pMyUnixApp;
			return (windowlessArgsWereSuccessful ? 0 : -1);
		}

		if (have_display) {

			// Step 3: Create windows as appropriate.
			// if some args are botched, it returns false and we should
			// continue out the door.
			// We used to check for bShowApp here.  It shouldn't be needed
			// anymore, because doWindowlessArgs was supposed to bail already. -PL

			if (pMyUnixApp->openCmdLineFiles(&Args))
			{
#if defined(EMBEDDED_TARGET) && EMBEDDED_TARGET == EMBEDDED_TARGET_HILDON
				s_bInitDone = true;
				pMyUnixApp->processStartupQueue();
#endif
				// turn over control to gtk
				gtk_main();
			}
			else
//.........这里部分代码省略.........

//.........这里部分代码省略.........

	/* Defer the exit if the traced process has an VFS call pending. */
	if (child->mp_flags & VFS_CALL)
		child->mp_exitstatus = (int) m_in.data;	/* save for later */
	else
		exit_proc(child, (int) m_in.data, FALSE /*dump_core*/);

	/* Do not reply to the caller until VFS has processed the exit
	 * request.
	 */
	return(SUSPEND);

  case T_SETOPT:	/* set trace options */
	child->mp_trace_flags = m_in.data;

	mp->mp_reply.reply_trace = 0;
	return(OK);

  case T_GETRANGE:
  case T_SETRANGE:	/* get/set range of values */
	r = sys_datacopy(who_e, (vir_bytes) m_in.PMTRACE_ADDR,
			SELF, (vir_bytes) &pr, (phys_bytes) sizeof(pr));
	if (r != OK) return(r);

	if (pr.pr_space != TS_INS && pr.pr_space != TS_DATA) return(EINVAL);
	if (pr.pr_size == 0 || pr.pr_size > LONG_MAX) return(EINVAL);

	seg = (pr.pr_space == TS_INS) ? T : D;
	if (req == T_GETRANGE)
		r = sys_vircopy(child->mp_endpoint, seg, (vir_bytes) pr.pr_addr,
			who_e, D, (vir_bytes) pr.pr_ptr,
			(phys_bytes) pr.pr_size);
	else
		r = sys_vircopy(who_e, D, (vir_bytes) pr.pr_ptr,
			child->mp_endpoint, seg, (vir_bytes) pr.pr_addr,
			(phys_bytes) pr.pr_size);

	if (r != OK) return(r);

	mp->mp_reply.reply_trace = 0;
	return(OK);

  case T_DETACH:	/* detach from traced process */
	if (m_in.data < 0 || m_in.data >= _NSIG) return(EINVAL);

	child->mp_tracer = NO_TRACER;

	/* Let all tracer-pending signals through the filter. */
	for (i = 1; i < _NSIG; i++) {
		if (sigismember(&child->mp_sigtrace, i)) {
			(void) sigdelset(&child->mp_sigtrace, i);
			check_sig(child->mp_pid, i, FALSE /* ksig */);
		}
	}

	if (m_in.data > 0) {		/* issue signal */
		sig_proc(child, (int) m_in.data, TRUE /*trace*/, 
			FALSE /* ksig */);
	}

	/* Resume the child as if nothing ever happened. */ 
	child->mp_flags &= ~STOPPED;
	child->mp_trace_flags = 0;

	check_pending(child);

	break;

  case T_RESUME: 
  case T_STEP:
  case T_SYSCALL:	/* resume execution */
	if (m_in.data < 0 || m_in.data >= _NSIG) return(EINVAL);

	if (m_in.data > 0) {		/* issue signal */
		sig_proc(child, (int) m_in.data, FALSE /*trace*/,
			FALSE /* ksig */);
	}

	/* If there are any other signals waiting to be delivered,
	 * feign a successful resumption.
	 */
	for (i = 1; i < _NSIG; i++) {
		if (sigismember(&child->mp_sigtrace, i)) {
			mp->mp_reply.reply_trace = 0;
			return(OK);
		}
	}

	child->mp_flags &= ~STOPPED;

	check_pending(child);

	break;
  }
  r = sys_trace(req, child->mp_endpoint, m_in.PMTRACE_ADDR, &m_in.data);
  if (r != OK) return(r);

  mp->mp_reply.reply_trace = m_in.data;
  return(OK);
}

static void remove_sync_sigs(sigset_t *sig_mask)
{
#ifdef SIGABRT
    sigdelset(sig_mask, SIGABRT);
#endif
#ifdef SIGBUS
    sigdelset(sig_mask, SIGBUS);
#endif
#ifdef SIGEMT
    sigdelset(sig_mask, SIGEMT);
#endif
#ifdef SIGFPE
    sigdelset(sig_mask, SIGFPE);
#endif
#ifdef SIGILL
    sigdelset(sig_mask, SIGILL);
#endif
#ifdef SIGIOT
    sigdelset(sig_mask, SIGIOT);
#endif
#ifdef SIGPIPE
    sigdelset(sig_mask, SIGPIPE);
#endif
#ifdef SIGSEGV
    sigdelset(sig_mask, SIGSEGV);
#endif
#ifdef SIGSYS
    sigdelset(sig_mask, SIGSYS);
#endif
#ifdef SIGTRAP
    sigdelset(sig_mask, SIGTRAP);
#endif

/* the rest of the signals removed from the mask in this function
 * absolutely must be removed; you cannot block synchronous signals
 * (requirement of pthreads API)
 *
 * SIGUSR2 is being removed from the mask for the convenience of
 * Purify users (Solaris, HP-UX, SGI) since Purify uses SIGUSR2
 */
#ifdef SIGUSR2
    sigdelset(sig_mask, SIGUSR2);
#endif
}

APR_DECLARE(apr_status_t) apr_signal_thread(int(*signal_handler)(int signum))
{
    sigset_t sig_mask;
#if APR_HAVE_SIGWAIT
    int (*sig_func)(int signum) = (int (*)(int))signal_handler;
#endif

    /* This thread will be the one responsible for handling signals */
    sigfillset(&sig_mask);

    /* On certain platforms, sigwait() returns EINVAL if any of various
     * unblockable signals are included in the mask.  This was first 
     * observed on AIX and Tru64.
     */
#ifdef SIGKILL
    sigdelset(&sig_mask, SIGKILL);
#endif
#ifdef SIGSTOP
    sigdelset(&sig_mask, SIGSTOP);
#endif
#ifdef SIGCONT
    sigdelset(&sig_mask, SIGCONT);
#endif
#ifdef SIGWAITING
    sigdelset(&sig_mask, SIGWAITING);
#endif

    /* no synchronous signals should be in the mask passed to sigwait() */
    remove_sync_sigs(&sig_mask);

    /* On AIX (4.3.3, at least), sigwait() won't wake up if the high-
     * order bit of the second word of flags is turned on.  sigdelset()
     * returns an error when trying to turn this off, so we'll turn it
     * off manually.
     *
     * Note that the private fields differ between 32-bit and 64-bit
     * and even between _ALL_SOURCE and !_ALL_SOURCE.  Except that on
     * AIX 4.3 32-bit builds and 64-bit builds use the same definition.
     *
     * Applicable AIX fixes such that this is no longer needed:
     *
     * APAR IY23096 for AIX 51B, fix included in AIX 51C, and
     * APAR IY24162 for 43X.
     */
#if defined(_AIX)
#if defined(__64BIT__) && defined(_AIXVERSION_510)
#ifdef _ALL_SOURCE
        sig_mask.ss_set[3] &= 0x7FFFFFFF;
#else /* not _ALL_SOURCE */
        sig_mask.__ss_set[3] &= 0x7FFFFFFF;
#endif
#else /* not 64-bit build, or 64-bit build on 4.3 */
#ifdef _ALL_SOURCE
        sig_mask.hisigs &= 0x7FFFFFFF;
#else /* not _ALL_SOURCE */
        sig_mask.__hisigs &= 0x7FFFFFFF;
#endif
#endif
#endif /* _AIX */

    while (1) {
#if APR_HAVE_SIGWAIT
        int signal_received;

        if (apr_sigwait(&sig_mask, &signal_received) != 0)
        {
            /* handle sigwait() error here */
        }
        
        if (sig_func(signal_received) == 1) {
            return APR_SUCCESS;
        }
#elif HAVE_SIGSUSPEND
	sigsuspend(&sig_mask);
#else
#error No apr_sigwait() and no sigsuspend()
#endif
    }
}

int
main(int argc, char **argv) {
    int status;
    pid_t waited;
    char *device, *real_device, *physicalDevice = NULL;
    char *boot = NULL;
    shvarFile *ifcfg;
    sigset_t blockedsigs, unblockedsigs;
    int pppdPid = 0;
    int timeout = 30;
    char *temp;
    gboolean dying = FALSE;
    int sendsig;
    gboolean connectedOnce = FALSE;
    int maxfail = 0;		// MAXFAIL Patch <[email protected]>

    if (argc < 2) {
	fprintf (stderr, "usage: ppp-watch <interface-name> [boot]\n");
	exit(30);
    }

    if (strncmp(argv[1], "ifcfg-", 6) == 0) {
	device = argv[1] + 6;
    } else {
	device = argv[1];
    }

    detach(device); /* Prepare a child process to monitor pppd.  When we
		       return, we'll be in the child. */

    if ((argc > 2) && (strcmp("boot", argv[2]) == 0)) {
	boot = argv[2];
    }

    ifcfg = shvarfilesGet(device);
    if (ifcfg == NULL)
	failureExit(28);

    real_device = svGetValue(ifcfg, "DEVICE");
    if (real_device == NULL)
	real_device = device;

    doPidFile(real_device);

    /* We'll want to know which signal interrupted our sleep below, so
     * attach a signal handler to these. */
    set_signal(SIGTERM, signal_tracker);
    set_signal(SIGINT, signal_tracker);
    set_signal(SIGHUP, signal_tracker);
    set_signal(SIGIO, signal_tracker);
    set_signal(SIGCHLD, signal_tracker);

    /* We time out only if we're being run at boot-time. */
    if (boot) {
	temp = svGetValue(ifcfg, "BOOTTIMEOUT");
	if (temp) {
	    timeout = atoi(temp);
	    if (timeout < 1) timeout = 1;
	    free(temp);
	} else {
	    timeout = 30;
	}
	set_signal(SIGALRM, signal_tracker);
	alarm(timeout);
    }

    /* Register us to get a signal when something changes. Yes, that's vague. */
    fork_exec(TRUE, "/sbin/netreport", NULL, NULL, NULL);

    /* Reset theSigchld, which should have been triggered by netreport. */
    theSigchld = 0;

    /* We don't set up the procmask until after we have received the netreport
     * signal.  Do so now. */
    sigemptyset(&blockedsigs);
    sigaddset(&blockedsigs, SIGTERM);
    sigaddset(&blockedsigs, SIGINT);
    sigaddset(&blockedsigs, SIGHUP);
    sigaddset(&blockedsigs, SIGIO);
    sigaddset(&blockedsigs, SIGCHLD);
    if (boot) {
	sigaddset(&blockedsigs, SIGALRM);
    }
    sigprocmask(SIG_BLOCK, &blockedsigs, NULL);

    sigfillset(&unblockedsigs);
    sigdelset(&unblockedsigs, SIGTERM);
    sigdelset(&unblockedsigs, SIGINT);
    sigdelset(&unblockedsigs, SIGHUP);
    sigdelset(&unblockedsigs, SIGIO);
    sigdelset(&unblockedsigs, SIGCHLD);
    if (boot) {
	sigdelset(&unblockedsigs, SIGALRM);
    }
    sigprocmask(SIG_UNBLOCK, &unblockedsigs, NULL);

    /* Initialize the retry timeout using the RETRYTIMEOUT setting. */
    temp = svGetValue(ifcfg, "RETRYTIMEOUT");
    if (temp) {
	timeout = atoi(temp);
//.........这里部分代码省略.........

/*
 * Initialize BlockSig, UnBlockSig, and StartupBlockSig.
 *
 * BlockSig is the set of signals to block when we are trying to block
 * signals.  This includes all signals we normally expect to get, but NOT
 * signals that should never be turned off.
 *
 * StartupBlockSig is the set of signals to block during startup packet
 * collection; it's essentially BlockSig minus SIGTERM, SIGQUIT, SIGALRM.
 *
 * UnBlockSig is the set of signals to block when we don't want to block
 * signals (is this ever nonzero??)
 */
void
pqinitmask(void)
{
	sigemptyset(&UnBlockSig);

	/* First set all signals, then clear some. */
	sigfillset(&BlockSig);
	sigfillset(&StartupBlockSig);

	/*
	 * Unmark those signals that should never be blocked. Some of these signal
	 * names don't exist on all platforms.  Most do, but might as well ifdef
	 * them all for consistency...
	 */
#ifdef SIGTRAP
	sigdelset(&BlockSig, SIGTRAP);
	sigdelset(&StartupBlockSig, SIGTRAP);
#endif
#ifdef SIGABRT
	sigdelset(&BlockSig, SIGABRT);
	sigdelset(&StartupBlockSig, SIGABRT);
#endif
#ifdef SIGILL
	sigdelset(&BlockSig, SIGILL);
	sigdelset(&StartupBlockSig, SIGILL);
#endif
#ifdef SIGFPE
	sigdelset(&BlockSig, SIGFPE);
	sigdelset(&StartupBlockSig, SIGFPE);
#endif
#ifdef SIGSEGV
	sigdelset(&BlockSig, SIGSEGV);
	sigdelset(&StartupBlockSig, SIGSEGV);
#endif
#ifdef SIGBUS
	sigdelset(&BlockSig, SIGBUS);
	sigdelset(&StartupBlockSig, SIGBUS);
#endif
#ifdef SIGSYS
	sigdelset(&BlockSig, SIGSYS);
	sigdelset(&StartupBlockSig, SIGSYS);
#endif
#ifdef SIGCONT
	sigdelset(&BlockSig, SIGCONT);
	sigdelset(&StartupBlockSig, SIGCONT);
#endif

/* Signals unique to startup */
#ifdef SIGQUIT
	sigdelset(&StartupBlockSig, SIGQUIT);
#endif
#ifdef SIGTERM
	sigdelset(&StartupBlockSig, SIGTERM);
#endif
#ifdef SIGALRM
	sigdelset(&StartupBlockSig, SIGALRM);
#endif
}

static void setup_signals(void)
{
  struct sigaction sa = { .sa_handler = signal_handler, .sa_flags = 0 };
  sigset_t ss;
  do
  {
    if (sigfillset(&ss) == -1) break;
    if (sigemptyset(&sa.sa_mask) == -1) break;
    if (sigaction(SIGCHLD, &sa, NULL) == -1 || sigdelset(&ss, SIGCHLD) == -1) break;
    if (sigaction(SIGUSR1, &sa, NULL) == -1 || sigdelset(&ss, SIGUSR1) == -1) break;
    if (sigaction(SIGUSR2, &sa, NULL) == -1 || sigdelset(&ss, SIGUSR2) == -1) break;
    if (sigprocmask(SIG_SETMASK, &ss, NULL) == -1) break;
    return;
  }
  while (false);
  fatal("Error while setting up signal handlers.\n");
}

static void child_setup_signals(void)
{
  do
  {
    struct sigaction sa = { .sa_handler = SIG_DFL, .sa_flags = 0 };
    if (sigemptyset(&sa.sa_mask) == -1) break;
    if (sigaction(SIGCHLD, &sa, NULL) == -1) break;
    if (sigaction(SIGUSR1, &sa, NULL) == -1) break;
    if (sigaction(SIGUSR2, &sa, NULL) == -1) break;
    if (sigprocmask(SIG_SETMASK, &sa.sa_mask, NULL) == -1) break;
    return;
  }
  while (false);
  fatal("<child> Error while setting up signal handlers.\n");
}

static void invoke_command(char *command, char **argv, pid_t *child_pid, int *ptm)
{
  char* slavename = open_ptm(ptm);
  if (slavename == NULL)
    fatal("Error while opening pseudo-terminal.\n");

  struct winsize wsize;
  if (ioctl(STDIN_FILENO, TIOCGWINSZ, &wsize) == -1)
    fatal("Error while getting the terminal size.\n");

  struct termios attr;
  if (tcgetattr(*ptm, &attr) == -1)
    fatal("Error while getting the pseudo-terminal attributes.\n");

  switch (*child_pid = fork())
  {
  case -1:
    fatal("Fork failed.\n");
  case 0:
    /* child: */
    drop_privileges();
    if (close(*ptm) == -1)
      fatal("<child> Error while closing the master pseudo-terminal\n");
    if (setsid() == -1)
      fatal("<child> Error while creating a session\n");
    assert(slavename != NULL);
    int pts = open(slavename, O_RDWR);
    if (pts == -1)
      fatal("<child> Error while opening the slave pseudo-terminal\n");
    init_pty(pts, &wsize, attr);

    child_setup_signals();
    execvp(command, argv);
    fatal("<child> Execution failed.\n");
  default:
    /* parent: */
    return;
  }
}

static void clear(void)
{
  writes(STDOUT_FILENO, "\033[0m\033[H\033[J");
}

int main ( int argc, char **argv )
{
    pthread_mutex_t     spinLockMutex;
    pid_t               childPid;
    struct sigaction    sa;
    sigset_t            sigmsk;
    size_t              len;
    ThreadCallback_t    callbacks;

    GlobalAbort = false;

    /* Parse the command line options */
    MainParseArgs( argc, argv );

#ifndef __CYGWIN__
    len = confstr( _CS_GNU_LIBPTHREAD_VERSION, NULL, 0 );
    if( len ) {
        pthreadsVersion = (char *)malloc(len);
        confstr( _CS_GNU_LIBPTHREAD_VERSION, pthreadsVersion, len );
    }

    if( !pthreadsVersion || strstr( pthreadsVersion, "linuxthreads" ) ) {
        fprintf( stderr, "beirdobot requires NPTL to operate correctly.\n\n"
                         "The signal handling in linuxthreads is just too "
                         "broken to use.\n\n" );
        exit( 1 );
    }
#else
    len = 0;
#endif

    /* Do we need to detach? */
    if( Daemon ) {
        childPid = fork();
        if( childPid < 0 ) {
            perror( "Couldn't detach in daemon mode" );
            _exit( 1 );
        }

        if( childPid != 0 ) {
            /* This is still the parent, report the child's pid and exit */
            printf( "[Detached as PID %d]\n", childPid );
            /* And exit the parent */
            _exit( 0 );
        }

        /* After this is in the detached child */

        /* Close stdin, stdout, stderr to release the tty */
        close(0);
        close(1);
        close(2);
    }

    mainThreadId = pthread_self();

    /* 
     * Setup the sigmasks for this thread (which is the parent to all others).
     * This will propogate to all children.
     */
    sigfillset( &sigmsk );
    sigdelset( &sigmsk, SIGUSR1 );
    sigdelset( &sigmsk, SIGUSR2 );
    sigdelset( &sigmsk, SIGHUP );
    sigdelset( &sigmsk, SIGWINCH );
    sigdelset( &sigmsk, SIGINT );
    sigdelset( &sigmsk, SIGSEGV );
    sigdelset( &sigmsk, SIGILL );
    sigdelset( &sigmsk, SIGFPE );
    pthread_sigmask( SIG_SETMASK, &sigmsk, NULL );

    /* Initialize the non-threadsafe CURL library functionality */
    curl_global_init( CURL_GLOBAL_ALL );

    /* Start up the Logging thread */
    logging_initialize(TRUE);

    memset( &callbacks, 0, sizeof(ThreadCallback_t) );
    callbacks.sighupFunc = mainSighup;
    thread_register( &mainThreadId, "thread_main", &callbacks );

    /* Setup signal handler for SIGUSR1 (toggles Debug) */
    sa.sa_sigaction = (sigAction_t)logging_toggle_debug;
    sigemptyset( &sa.sa_mask );
    sa.sa_flags = SA_RESTART;
    sigaction( SIGUSR1, &sa, NULL );

    /* Setup the exit handler */
    atexit( MainDelayExit );

    /* Setup signal handler for SIGINT (shut down cleanly) */
    sa.sa_sigaction = signal_interrupt;
    sigemptyset( &sa.sa_mask );
    sa.sa_flags = SA_RESTART;
    sigaction( SIGINT, &sa, NULL );
    
    /* Setup signal handlers that are to be propogated to all threads */
    sa.sa_sigaction = signal_everyone;
    sigemptyset( &sa.sa_mask );
    sa.sa_flags = SA_RESTART | SA_SIGINFO;
//.........这里部分代码省略.........

/*
 * Main entry point for walwriter process
 *
 * This is invoked from BootstrapMain, which has already created the basic
 * execution environment, but not enabled signals yet.
 */
void
WalWriterMain(void)
{
	sigjmp_buf	local_sigjmp_buf;
	MemoryContext walwriter_context;

	/*
	 * If possible, make this process a group leader, so that the postmaster
	 * can signal any child processes too.	(walwriter probably never has any
	 * child processes, but for consistency we make all postmaster child
	 * processes do this.)
	 */
#ifdef HAVE_SETSID
	if (setsid() < 0)
		elog(FATAL, "setsid() failed: %m");
#endif

	/*
	 * Properly accept or ignore signals the postmaster might send us
	 *
	 * We have no particular use for SIGINT at the moment, but seems
	 * reasonable to treat like SIGTERM.
	 */
	pqsignal(SIGHUP, WalSigHupHandler); /* set flag to read config file */
	pqsignal(SIGINT, WalShutdownHandler);		/* request shutdown */
	pqsignal(SIGTERM, WalShutdownHandler);		/* request shutdown */
	pqsignal(SIGQUIT, wal_quickdie);	/* hard crash time */
	pqsignal(SIGALRM, SIG_IGN);
	pqsignal(SIGPIPE, SIG_IGN);
	pqsignal(SIGUSR1, SIG_IGN); /* reserve for ProcSignal */
	pqsignal(SIGUSR2, SIG_IGN); /* not used */

	/*
	 * Reset some signals that are accepted by postmaster but not here
	 */
	pqsignal(SIGCHLD, SIG_DFL);
	pqsignal(SIGTTIN, SIG_DFL);
	pqsignal(SIGTTOU, SIG_DFL);
	pqsignal(SIGCONT, SIG_DFL);
	pqsignal(SIGWINCH, SIG_DFL);

	/* We allow SIGQUIT (quickdie) at all times */
	sigdelset(&BlockSig, SIGQUIT);

	/*
	 * Create a resource owner to keep track of our resources (not clear that
	 * we need this, but may as well have one).
	 */
	CurrentResourceOwner = ResourceOwnerCreate(NULL, "Wal Writer");

	/*
	 * Create a memory context that we will do all our work in.  We do this so
	 * that we can reset the context during error recovery and thereby avoid
	 * possible memory leaks.  Formerly this code just ran in
	 * TopMemoryContext, but resetting that would be a really bad idea.
	 */
	walwriter_context = AllocSetContextCreate(TopMemoryContext,
											  "Wal Writer",
											  ALLOCSET_DEFAULT_MINSIZE,
											  ALLOCSET_DEFAULT_INITSIZE,
											  ALLOCSET_DEFAULT_MAXSIZE);
	MemoryContextSwitchTo(walwriter_context);

	/*
	 * If an exception is encountered, processing resumes here.
	 *
	 * This code is heavily based on bgwriter.c, q.v.
	 */
	if (sigsetjmp(local_sigjmp_buf, 1) != 0)
	{
		/* Since not using PG_TRY, must reset error stack by hand */
		error_context_stack = NULL;

		/* Prevent interrupts while cleaning up */
		HOLD_INTERRUPTS();

		/* Report the error to the server log */
		EmitErrorReport();

		/*
		 * These operations are really just a minimal subset of
		 * AbortTransaction().	We don't have very many resources to worry
		 * about in walwriter, but we do have LWLocks, and perhaps buffers?
		 */
		LWLockReleaseAll();
		AbortBufferIO();
		UnlockBuffers();
		/* buffer pins are released here: */
		ResourceOwnerRelease(CurrentResourceOwner,
							 RESOURCE_RELEASE_BEFORE_LOCKS,
							 false, true);
		/* we needn't bother with the other ResourceOwnerRelease phases */
		AtEOXact_Buffers(false);
		AtEOXact_Files();
//.........这里部分代码省略.........

static void
nto_resume (struct thread_resume *resume_info, size_t n)
{
  /* We can only work in all-stop mode.  */
  procfs_status status;
  procfs_run run;
  int err;

  TRACE ("%s\n", __func__);
  /* Workaround for aliasing rules violation. */
  sigset_t *run_fault = (sigset_t *) (void *) &run.fault;

  nto_set_thread (resume_info->thread);

  run.flags = _DEBUG_RUN_FAULT | _DEBUG_RUN_TRACE;
  if (resume_info->kind == resume_step)
    run.flags |= _DEBUG_RUN_STEP;
  run.flags |= _DEBUG_RUN_ARM;

  sigemptyset (run_fault);
  sigaddset (run_fault, FLTBPT);
  sigaddset (run_fault, FLTTRACE);
  sigaddset (run_fault, FLTILL);
  sigaddset (run_fault, FLTPRIV);
  sigaddset (run_fault, FLTBOUNDS);
  sigaddset (run_fault, FLTIOVF);
  sigaddset (run_fault, FLTIZDIV);
  sigaddset (run_fault, FLTFPE);
  sigaddset (run_fault, FLTPAGE);
  sigaddset (run_fault, FLTSTACK);
  sigaddset (run_fault, FLTACCESS);

  sigemptyset (&run.trace);
  if (resume_info->sig)
    {
      int signal_to_pass;

      devctl (nto_inferior.ctl_fd, DCMD_PROC_STATUS, &status, sizeof (status),