asterisk.c

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2006, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */


/* Doxygenified Copyright Header */
/*!
 * \mainpage Asterisk -- An Open Source Telephony Toolkit
 *
 * \par Developer Documentation for Asterisk
 * This is the main developer documentation for Asterisk. It is 
 * generated by running "make progdocs".
 * \par Additional documentation
 * \arg \ref DevDoc 
 * \arg \ref ConfigFiles
 *
 * \section copyright Copyright and author
 *
 * Copyright (C) 1999 - 2006, Digium, Inc.
 * Asterisk is a trade mark registered by Digium, Inc.
 *
 * \author Mark Spencer <markster@digium.com>
 * Also see \ref AstCREDITS
 *
 * \section license License
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 *
 * \verbinclude LICENSE
 *
 */

/*! \file
  \brief Top level source file for Asterisk  - the Open Source PBX. Implementation
  of PBX core functions and CLI interface.
  
 */

#include <unistd.h>
#include <stdlib.h>
#include <sys/time.h>
#include <fcntl.h>
#include <stdio.h>
#include <signal.h>
#include <sched.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/wait.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include <sys/resource.h>
#include <grp.h>
#include <pwd.h>
#include <sys/stat.h>
#include <regex.h>

#ifdef linux
#include <sys/prctl.h>
#endif

#if  defined(__FreeBSD__) || defined( __NetBSD__ ) || defined(SOLARIS)
#include <netdb.h>
#if defined(SOLARIS)
extern int daemon(int, int);  /* defined in libresolv of all places */
#endif
#endif

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision$")

#include "asterisk/logger.h"
#include "asterisk/options.h"
#include "asterisk/cli.h"
#include "asterisk/channel.h"
#include "asterisk/ulaw.h"
#include "asterisk/alaw.h"
#include "asterisk/callerid.h"
#include "asterisk/module.h"
#include "asterisk/image.h"
#include "asterisk/tdd.h"
#include "asterisk/term.h"
#include "asterisk/manager.h"
#include "asterisk/cdr.h"
#include "asterisk/pbx.h"
#include "asterisk/enum.h"
#include "asterisk/rtp.h"
#include "asterisk/http.h"
#if defined(T38_SUPPORT)
#include "asterisk/udptl.h"
#endif
#include "asterisk/app.h"
#include "asterisk/lock.h"
#include "asterisk/utils.h"
#include "asterisk/file.h"
#include "asterisk/io.h"
#include "asterisk/lock.h"
#include "editline/histedit.h"
#include "asterisk/config.h"
#include "asterisk/version.h"
#include "asterisk/linkedlists.h"
#include "asterisk/devicestate.h"
#include "asterisk/compat.h"

#include "asterisk/doxyref.h"		/* Doxygen documentation */

#include "defaults.h"

#ifndef AF_LOCAL
#define AF_LOCAL AF_UNIX
#define PF_LOCAL PF_UNIX
#endif

#define AST_MAX_CONNECTS 128
#define NUM_MSGS 64

/*! \brief Welcome message when starting a CLI interface */
#define WELCOME_MESSAGE \
	ast_verbose("Asterisk " ASTERISK_VERSION ", Copyright (C) 1999 - 2006 Digium, Inc. and others.\n"); \
	ast_verbose("Created by Mark Spencer <markster@digium.com>\n"); \
	ast_verbose("Asterisk comes with ABSOLUTELY NO WARRANTY; type 'show warranty' for details.\n"); \
	ast_verbose("This is free software, with components licensed under the GNU General Public\n"); \
	ast_verbose("License version 2 and other licenses; you are welcome to redistribute it under\n"); \
	ast_verbose("certain conditions. Type 'show license' for details.\n"); \
	ast_verbose("=========================================================================\n")

/*! \defgroup main_options 
 \brief Main configuration options from \ref Config_ast "asterisk.conf" or 
  the operating system command line when starting Asterisk 
  Some of them can be changed in the CLI 
 */
/*! @{ */

struct ast_flags ast_options = { AST_DEFAULT_OPTIONS };

int option_verbose = 0;				/*!< Verbosity level */
int option_debug = 0;				/*!< Debug level */

double option_maxload = 0.0;			/*!< Max load avg on system */
int option_maxcalls = 0;			/*!< Max number of active calls */

/*! @} */

char record_cache_dir[AST_CACHE_DIR_LEN] = AST_TMP_DIR;
char debug_filename[AST_FILENAME_MAX] = "";

static int ast_socket = -1;		/*!< UNIX Socket for allowing remote control */
static int ast_consock = -1;		/*!< UNIX Socket for controlling another asterisk */
int ast_mainpid;
struct console {
	int fd;				/*!< File descriptor */
	int p[2];			/*!< Pipe */
	pthread_t t;			/*!< Thread of handler */
};

struct ast_atexit {
	void (*func)(void);
	AST_LIST_ENTRY(ast_atexit) list;
};

static AST_LIST_HEAD_STATIC(atexits, ast_atexit);

time_t ast_startuptime;
time_t ast_lastreloadtime;

static History *el_hist = NULL;
static EditLine *el = NULL;
static char *remotehostname;

struct console consoles[AST_MAX_CONNECTS];

char defaultlanguage[MAX_LANGUAGE] = DEFAULT_LANGUAGE;

static int ast_el_add_history(char *);
static int ast_el_read_history(char *);
static int ast_el_write_history(char *);

char ast_config_AST_CONFIG_DIR[AST_CONFIG_MAX_PATH];
char ast_config_AST_CONFIG_FILE[AST_CONFIG_MAX_PATH];
char ast_config_AST_MODULE_DIR[AST_CONFIG_MAX_PATH];
char ast_config_AST_SPOOL_DIR[AST_CONFIG_MAX_PATH];
char ast_config_AST_MONITOR_DIR[AST_CONFIG_MAX_PATH];
char ast_config_AST_VAR_DIR[AST_CONFIG_MAX_PATH];
char ast_config_AST_LOG_DIR[AST_CONFIG_MAX_PATH];
char ast_config_AST_AGI_DIR[AST_CONFIG_MAX_PATH];
char ast_config_AST_DB[AST_CONFIG_MAX_PATH];
char ast_config_AST_KEY_DIR[AST_CONFIG_MAX_PATH];
char ast_config_AST_PID[AST_CONFIG_MAX_PATH];
char ast_config_AST_SOCKET[AST_CONFIG_MAX_PATH];
char ast_config_AST_RUN_DIR[AST_CONFIG_MAX_PATH];
char ast_config_AST_RUN_USER[AST_CONFIG_MAX_PATH];
char ast_config_AST_RUN_GROUP[AST_CONFIG_MAX_PATH];
char ast_config_AST_CTL_PERMISSIONS[AST_CONFIG_MAX_PATH];
char ast_config_AST_CTL_OWNER[AST_CONFIG_MAX_PATH] = "\0";
char ast_config_AST_CTL_GROUP[AST_CONFIG_MAX_PATH] = "\0";
char ast_config_AST_CTL[AST_CONFIG_MAX_PATH] = "asterisk.ctl";
char ast_config_AST_SYSTEM_NAME[20] = "";

static char *_argv[256];
static int shuttingdown = 0;
static int restartnow = 0;
static pthread_t consolethread = AST_PTHREADT_NULL;

static char randompool[256];

#if !defined(LOW_MEMORY)
struct file_version {
	AST_LIST_ENTRY(file_version) list;
	const char *file;
	char *version;
};

static AST_LIST_HEAD_STATIC(file_versions, file_version);

void ast_register_file_version(const char *file, const char *version)
{
	struct file_version *new;
	char *work;
	size_t version_length;

	work = ast_strdupa(version);
	work = ast_strip(ast_strip_quoted(work, "$", "$"));
	version_length = strlen(work) + 1;
	
	if (!(new = ast_calloc(1, sizeof(*new) + version_length)))
		return;

	new->file = file;
	new->version = (char *) new + sizeof(*new);
	memcpy(new->version, work, version_length);
	AST_LIST_LOCK(&file_versions);
	AST_LIST_INSERT_HEAD(&file_versions, new, list);
	AST_LIST_UNLOCK(&file_versions);
}

void ast_unregister_file_version(const char *file)
{
	struct file_version *find;

	AST_LIST_LOCK(&file_versions);
	AST_LIST_TRAVERSE_SAFE_BEGIN(&file_versions, find, list) {
		if (!strcasecmp(find->file, file)) {
			AST_LIST_REMOVE_CURRENT(&file_versions, list);
			break;
		}
	}
	AST_LIST_TRAVERSE_SAFE_END;
	AST_LIST_UNLOCK(&file_versions);
	if (find)
		free(find);
}

static char show_version_files_help[] = 
"Usage: show version files [like <pattern>]\n"
"       Shows the revision numbers of the files used to build this copy of Asterisk.\n"
"       Optional regular expression pattern is used to filter the file list.\n";

/*! CLI command to list module versions */
static int handle_show_version_files(int fd, int argc, char *argv[])
{
#define FORMAT "%-25.25s %-40.40s\n"
	struct file_version *iterator;
	regex_t regexbuf;
	int havepattern = 0;
	int havename = 0;
	int count_files = 0;

	switch (argc) {
	case 5:
		if (!strcasecmp(argv[3], "like")) {
			if (regcomp(&regexbuf, argv[4], REG_EXTENDED | REG_NOSUB))
				return RESULT_SHOWUSAGE;
			havepattern = 1;
		} else
			return RESULT_SHOWUSAGE;
		break;
	case 4:
		havename = 1;
		break;
	case 3:
		break;
	default:
		return RESULT_SHOWUSAGE;
	}

	ast_cli(fd, FORMAT, "File", "Revision");
	ast_cli(fd, FORMAT, "----", "--------");
	AST_LIST_LOCK(&file_versions);
	AST_LIST_TRAVERSE(&file_versions, iterator, list) {
		if (havename && strcasecmp(iterator->file, argv[3]))
			continue;

		if (havepattern && regexec(&regexbuf, iterator->file, 0, NULL, 0))
			continue;

		ast_cli(fd, FORMAT, iterator->file, iterator->version);
		count_files++;
		if (havename)
			break;
	}
	AST_LIST_UNLOCK(&file_versions);
	if (!havename) {
		ast_cli(fd, "%d files listed.\n", count_files);
	}

	if (havepattern)
		regfree(&regexbuf);

	return RESULT_SUCCESS;
#undef FORMAT
}

static char *complete_show_version_files(const char *line, const char *word, int pos, int state)
{
	struct file_version *find;
	int which = 0;
	char *ret = NULL;
	int matchlen = strlen(word);

	if (pos != 3)
		return NULL;

	AST_LIST_LOCK(&file_versions);
	AST_LIST_TRAVERSE(&file_versions, find, list) {
		if (!strncasecmp(word, find->file, matchlen)) {
			if (++which > state) {
				ret = strdup(find->file);
				break;
			}
		}
	}
	AST_LIST_UNLOCK(&file_versions);

	return ret;
}
#endif /* ! LOW_MEMORY */

int ast_register_atexit(void (*func)(void))
{
	int res = -1;
	struct ast_atexit *ae;
	ast_unregister_atexit(func);	
	AST_LIST_LOCK(&atexits);
	if ((ae = ast_calloc(1, sizeof(*ae)))) {
		AST_LIST_INSERT_HEAD(&atexits, ae, list);
		ae->func = func;
		res = 0;
	}
	AST_LIST_UNLOCK(&atexits);
	return res;
}

void ast_unregister_atexit(void (*func)(void))
{
	struct ast_atexit *ae;
	AST_LIST_LOCK(&atexits);
	AST_LIST_TRAVERSE_SAFE_BEGIN(&atexits, ae, list) {
		if (ae->func == func) {
			AST_LIST_REMOVE_CURRENT(&atexits, list);
			break;
		}
	}
	AST_LIST_TRAVERSE_SAFE_END
	AST_LIST_UNLOCK(&atexits);
}

static int fdprint(int fd, const char *s)
{
	return write(fd, s, strlen(s) + 1);
}

/*! NULL handler so we can collect the child exit status */
static void null_sig_handler(int signal)
{

}

AST_MUTEX_DEFINE_STATIC(safe_system_lock);
static unsigned int safe_system_level = 0;
static void *safe_system_prev_handler;

int ast_safe_system(const char *s)
{
	pid_t pid;
	int x;
	int res;
	struct rusage rusage;
	int status;
	unsigned int level;

	/* keep track of how many ast_safe_system() functions
	   are running at this moment
	*/
	ast_mutex_lock(&safe_system_lock);
	level = safe_system_level++;

	/* only replace the handler if it has not already been done */
	if (level == 0)
		safe_system_prev_handler = signal(SIGCHLD, null_sig_handler);

	ast_mutex_unlock(&safe_system_lock);

	pid = fork();

	if (pid == 0) {
		/* Close file descriptors and launch system command */
		for (x = STDERR_FILENO + 1; x < 4096; x++)
			close(x);
		execl("/bin/sh", "/bin/sh", "-c", s, NULL);
		exit(1);
	} else if (pid > 0) {
		for(;;) {
			res = wait4(pid, &status, 0, &rusage);
			if (res > -1) {
				res = WIFEXITED(status) ? WEXITSTATUS(status) : -1;
				break;
			} else if (errno != EINTR) 
				break;
		}
	} else {
		ast_log(LOG_WARNING, "Fork failed: %s\n", strerror(errno));
		res = -1;
	}

	ast_mutex_lock(&safe_system_lock);
	level = --safe_system_level;

	/* only restore the handler if we are the last one */
	if (level == 0)
		signal(SIGCHLD, safe_system_prev_handler);

	ast_mutex_unlock(&safe_system_lock);

	return res;
}

/*!
 * write the string to all attached console clients
 */
static void ast_network_puts(const char *string)
{
	int x;
	for (x=0; x < AST_MAX_CONNECTS; x++) {
		if (consoles[x].fd > -1) 
			fdprint(consoles[x].p[1], string);
	}
}

/*!
 * write the string to the console, and all attached
 * console clients
 */
void ast_console_puts(const char *string)
{
	fputs(string, stdout);
	fflush(stdout);
	ast_network_puts(string);
}

static void network_verboser(const char *s, int pos, int replace, int complete)
	/* ARGUSED */
{
	if (replace) {
		char *t;
		if ((t = alloca(strlen(s) + 2))) {
			sprintf(t, "\r%s", s);
			if (complete)
				ast_network_puts(t);
		} else {
			ast_log(LOG_ERROR, "Out of memory\n");
			ast_network_puts(s);
		}
	} else {
		if (complete)
			ast_network_puts(s);
	}
}

static pthread_t lthread;

static void *netconsole(void *vconsole)
{
	struct console *con = vconsole;
	char hostname[MAXHOSTNAMELEN] = "";
	char tmp[512];
	int res;
	struct pollfd fds[2];
	
	if (gethostname(hostname, sizeof(hostname)-1))
		ast_copy_string(hostname, "<Unknown>", sizeof(hostname));
	snprintf(tmp, sizeof(tmp), "%s/%d/%s\n", hostname, ast_mainpid, ASTERISK_VERSION);
	fdprint(con->fd, tmp);
	for(;;) {
		fds[0].fd = con->fd;
		fds[0].events = POLLIN;
		fds[0].revents = 0;
		fds[1].fd = con->p[0];
		fds[1].events = POLLIN;
		fds[1].revents = 0;

		res = poll(fds, 2, -1);
		if (res < 0) {
			if (errno != EINTR)
				ast_log(LOG_WARNING, "poll returned < 0: %s\n", strerror(errno));
			continue;
		}
		if (fds[0].revents) {
			res = read(con->fd, tmp, sizeof(tmp));
			if (res < 1) {
				break;
			}
			tmp[res] = 0;
			ast_cli_command(con->fd, tmp);
		}
		if (fds[1].revents) {
			res = read(con->p[0], tmp, sizeof(tmp));
			if (res < 1) {
				ast_log(LOG_ERROR, "read returned %d\n", res);
				break;
			}
			res = write(con->fd, tmp, res);
			if (res < 1)
				break;
		}
	}
	if (option_verbose > 2) 
		ast_verbose(VERBOSE_PREFIX_3 "Remote UNIX connection disconnected\n");
	close(con->fd);
	close(con->p[0]);
	close(con->p[1]);
	con->fd = -1;
	
	return NULL;
}

static void *listener(void *unused)
{
	struct sockaddr_un sunaddr;
	int s;
	socklen_t len;
	int x;
	int flags;
	struct pollfd fds[1];
	pthread_attr_t attr;
	pthread_attr_init(&attr);
	pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
	for (;;) {
		if (ast_socket < 0)
			return NULL;
		fds[0].fd = ast_socket;
		fds[0].events = POLLIN;
		s = poll(fds, 1, -1);
		if (s < 0) {
			if (errno != EINTR)
				ast_log(LOG_WARNING, "poll returned error: %s\n", strerror(errno));
			continue;
		}
		len = sizeof(sunaddr);
		s = accept(ast_socket, (struct sockaddr *)&sunaddr, &len);
		if (s < 0) {
			if (errno != EINTR)
				ast_log(LOG_WARNING, "Accept returned %d: %s\n", s, strerror(errno));
		} else {
			for (x = 0; x < AST_MAX_CONNECTS; x++) {
				if (consoles[x].fd < 0) {
					if (socketpair(AF_LOCAL, SOCK_STREAM, 0, consoles[x].p)) {
						ast_log(LOG_ERROR, "Unable to create pipe: %s\n", strerror(errno));
						consoles[x].fd = -1;
						fdprint(s, "Server failed to create pipe\n");
						close(s);
						break;
					}
					flags = fcntl(consoles[x].p[1], F_GETFL);
					fcntl(consoles[x].p[1], F_SETFL, flags | O_NONBLOCK);
					consoles[x].fd = s;
					if (ast_pthread_create(&consoles[x].t, &attr, netconsole, &consoles[x])) {
						ast_log(LOG_ERROR, "Unable to spawn thread to handle connection: %s\n", strerror(errno));
						consoles[x].fd = -1;
						fdprint(s, "Server failed to spawn thread\n");
						close(s);
					}
					break;
				}
			}
			if (x >= AST_MAX_CONNECTS) {
				fdprint(s, "No more connections allowed\n");
				ast_log(LOG_WARNING, "No more connections allowed\n");
				close(s);
			} else if (consoles[x].fd > -1) {
				if (option_verbose > 2) 
					ast_verbose(VERBOSE_PREFIX_3 "Remote UNIX connection\n");
			}
		}
	}
	return NULL;
}

static int ast_makesocket(void)
{
	struct sockaddr_un sunaddr;
	int res;
	int x;
	uid_t uid = -1;
	gid_t gid = -1;

	for (x = 0; x < AST_MAX_CONNECTS; x++)	
		consoles[x].fd = -1;
	unlink(ast_config_AST_SOCKET);
	ast_socket = socket(PF_LOCAL, SOCK_STREAM, 0);
	if (ast_socket < 0) {
		ast_log(LOG_WARNING, "Unable to create control socket: %s\n", strerror(errno));
		return -1;
	}		
	memset(&sunaddr, 0, sizeof(sunaddr));
	sunaddr.sun_family = AF_LOCAL;
	ast_copy_string(sunaddr.sun_path, ast_config_AST_SOCKET, sizeof(sunaddr.sun_path));
	res = bind(ast_socket, (struct sockaddr *)&sunaddr, sizeof(sunaddr));
	if (res) {
		ast_log(LOG_WARNING, "Unable to bind socket to %s: %s\n", ast_config_AST_SOCKET, strerror(errno));
		close(ast_socket);
		ast_socket = -1;
		return -1;
	}
	res = listen(ast_socket, 2);
	if (res < 0) {
		ast_log(LOG_WARNING, "Unable to listen on socket %s: %s\n", ast_config_AST_SOCKET, strerror(errno));
		close(ast_socket);
		ast_socket = -1;
		return -1;
	}
	ast_register_verbose(network_verboser);
	ast_pthread_create(&lthread, NULL, listener, NULL);

	if (!ast_strlen_zero(ast_config_AST_CTL_OWNER)) {
		struct passwd *pw;
		if ((pw = getpwnam(ast_config_AST_CTL_OWNER)) == NULL) {
			ast_log(LOG_WARNING, "Unable to find uid of user %s\n", ast_config_AST_CTL_OWNER);
		} else {
			uid = pw->pw_uid;
		}
	}
		
	if (!ast_strlen_zero(ast_config_AST_CTL_GROUP)) {
		struct group *grp;
		if ((grp = getgrnam(ast_config_AST_CTL_GROUP)) == NULL) {
			ast_log(LOG_WARNING, "Unable to find gid of group %s\n", ast_config_AST_CTL_GROUP);
		} else {
			gid = grp->gr_gid;
		}
	}

	if (chown(ast_config_AST_SOCKET, uid, gid) < 0)
		ast_log(LOG_WARNING, "Unable to change ownership of %s: %s\n", ast_config_AST_SOCKET, strerror(errno));

	if (!ast_strlen_zero(ast_config_AST_CTL_PERMISSIONS)) {
		int p1;
		mode_t p;
		sscanf(ast_config_AST_CTL_PERMISSIONS, "%o", &p1);
		p = p1;
		if ((chmod(ast_config_AST_SOCKET, p)) < 0)
			ast_log(LOG_WARNING, "Unable to change file permissions of %s: %s\n", ast_config_AST_SOCKET, strerror(errno));
	}

	return 0;
}

static int ast_tryconnect(void)
{
	struct sockaddr_un sunaddr;
	int res;
	ast_consock = socket(PF_LOCAL, SOCK_STREAM, 0);
	if (ast_consock < 0) {
		ast_log(LOG_WARNING, "Unable to create socket: %s\n", strerror(errno));
		return 0;
	}
	memset(&sunaddr, 0, sizeof(sunaddr));
	sunaddr.sun_family = AF_LOCAL;
	ast_copy_string(sunaddr.sun_path, (char *)ast_config_AST_SOCKET, sizeof(sunaddr.sun_path));
	res = connect(ast_consock, (struct sockaddr *)&sunaddr, sizeof(sunaddr));
	if (res) {
		close(ast_consock);
		ast_consock = -1;
		return 0;
	} else
		return 1;
}

/*! Urgent handler
 Called by soft_hangup to interrupt the poll, read, or other
 system call.  We don't actually need to do anything though.  
 Remember: Cannot EVER ast_log from within a signal handler 
 SLD: seems to be some pthread activity relating to the printf anyway:
 which is leading to a deadlock? 
 */
static void urg_handler(int num)
{
#if 0
	if (option_debug > 2) 
		printf("-- Asterisk Urgent handler\n");
#endif
	signal(num, urg_handler);
	return;
}

static void hup_handler(int num)
{
	if (option_verbose > 1) 
		printf("Received HUP signal -- Reloading configs\n");
	if (restartnow)
		execvp(_argv[0], _argv);
	/* XXX This could deadlock XXX */
	ast_module_reload(NULL);
	signal(num, hup_handler);
}

static void child_handler(int sig)
{
	/* Must not ever ast_log or ast_verbose within signal handler */
	int n, status;

	/*
	 * Reap all dead children -- not just one
	 */
	for (n = 0; wait4(-1, &status, WNOHANG, NULL) > 0; n++)
		;
	if (n == 0 && option_debug)	
		printf("Huh?  Child handler, but nobody there?\n");
	signal(sig, child_handler);
}

/*! Set an X-term or screen title */
static void set_title(char *text)
{
	if (getenv("TERM") && strstr(getenv("TERM"), "xterm"))
		fprintf(stdout, "\033]2;%s\007", text);
}

static void set_icon(char *text)
{
	if (getenv("TERM") && strstr(getenv("TERM"), "xterm"))
		fprintf(stdout, "\033]1;%s\007", text);
}

/*! We set ourselves to a high priority, that we might pre-empt everything
   else.  If your PBX has heavy activity on it, this is a good thing.  */
int ast_set_priority(int pri)
{
	struct sched_param sched;
	memset(&sched, 0, sizeof(sched));
#ifdef __linux__
	if (pri) {  
		sched.sched_priority = 10;
		if (sched_setscheduler(0, SCHED_RR, &sched)) {
			ast_log(LOG_WARNING, "Unable to set high priority\n");
			return -1;
		} else
			if (option_verbose)
				ast_verbose("Set to realtime thread\n");
	} else {
		sched.sched_priority = 0;
		if (sched_setscheduler(0, SCHED_OTHER, &sched)) {
			ast_log(LOG_WARNING, "Unable to set normal priority\n");
			return -1;
		}
	}
#else
	if (pri) {
		if (setpriority(PRIO_PROCESS, 0, -10) == -1) {
			ast_log(LOG_WARNING, "Unable to set high priority\n");
			return -1;
		} else
			if (option_verbose)
				ast_verbose("Set to high priority\n");
	} else {
		if (setpriority(PRIO_PROCESS, 0, 0) == -1) {
			ast_log(LOG_WARNING, "Unable to set normal priority\n");
			return -1;
		}
	}
#endif
	return 0;
}

static void ast_run_atexits(void)
{
	struct ast_atexit *ae;
	AST_LIST_LOCK(&atexits);
	AST_LIST_TRAVERSE(&atexits, ae, list) {
		if (ae->func) 
			ae->func();
	}
	AST_LIST_UNLOCK(&atexits);
}

static void quit_handler(int num, int nice, int safeshutdown, int restart)
{
	char filename[80] = "";
	time_t s,e;
	int x;
	/* Try to get as many CDRs as possible submitted to the backend engines (if in batch mode) */
	ast_cdr_engine_term();
	if (safeshutdown) {
		shuttingdown = 1;
		if (!nice) {
			/* Begin shutdown routine, hanging up active channels */
			ast_begin_shutdown(1);
			if (option_verbose && ast_opt_console)
				ast_verbose("Beginning asterisk %s....\n", restart ? "restart" : "shutdown");
			time(&s);
			for (;;) {
				time(&e);
				/* Wait up to 15 seconds for all channels to go away */
				if ((e - s) > 15)
					break;
				if (!ast_active_channels())
					break;
				if (!shuttingdown)
					break;
				/* Sleep 1/10 of a second */
				usleep(100000);
			}
		} else {
			if (nice < 2)
				ast_begin_shutdown(0);
			if (option_verbose && ast_opt_console)
				ast_verbose("Waiting for inactivity to perform %s...\n", restart ? "restart" : "halt");
			for (;;) {
				if (!ast_active_channels())
					break;
				if (!shuttingdown)
					break;
				sleep(1);
			}
		}

		if (!shuttingdown) {
			if (option_verbose && ast_opt_console)
				ast_verbose("Asterisk %s cancelled.\n", restart ? "restart" : "shutdown");
			return;
		}
	}
	if (ast_opt_console || ast_opt_remote) {
		if (getenv("HOME")) 
			snprintf(filename, sizeof(filename), "%s/.asterisk_history", getenv("HOME"));
		if (!ast_strlen_zero(filename))
			ast_el_write_history(filename);
		if (el != NULL)
			el_end(el);
		if (el_hist != NULL)
			history_end(el_hist);
	}
	if (option_verbose)
		ast_verbose("Executing last minute cleanups\n");
	ast_run_atexits();
	/* Called on exit */
	if (option_verbose && ast_opt_console)
		ast_verbose("Asterisk %s ending (%d).\n", ast_active_channels() ? "uncleanly" : "cleanly", num);
	else if (option_debug)
		ast_log(LOG_DEBUG, "Asterisk ending (%d).\n", num);
	manager_event(EVENT_FLAG_SYSTEM, "Shutdown", "Shutdown: %s\r\nRestart: %s\r\n", ast_active_channels() ? "Uncleanly" : "Cleanly", restart ? "True" : "False");
	if (ast_socket > -1) {
		close(ast_socket);
		ast_socket = -1;
		unlink(ast_config_AST_SOCKET);
		pthread_cancel(lthread);
	}
	if (ast_consock > -1)
		close(ast_consock);
	if (!ast_opt_remote)
		unlink(ast_config_AST_PID);
	printf(term_quit());
	if (restart) {
		if (option_verbose || ast_opt_console)
			ast_verbose("Preparing for Asterisk restart...\n");
		/* Mark all FD's for closing on exec */
		for (x=3; x < 32768; x++) {
			fcntl(x, F_SETFD, FD_CLOEXEC);
		}
		if (option_verbose || ast_opt_console)
			ast_verbose("Restarting Asterisk NOW...\n");
		restartnow = 1;

		/* close logger */
		close_logger();

		/* If there is a consolethread running send it a SIGHUP 
		   so it can execvp, otherwise we can do it ourselves */
		if ((consolethread != AST_PTHREADT_NULL) && (consolethread != pthread_self())) {
			pthread_kill(consolethread, SIGHUP);
			/* Give the signal handler some time to complete */
			sleep(2);
		} else
			execvp(_argv[0], _argv);
	
	} else {
		/* close logger */
		close_logger();
	}
	exit(0);
}

static void __quit_handler(int num)
{
	quit_handler(num, 0, 1, 0);
}

static const char *fix_header(char *outbuf, int maxout, const char *s, char *cmp)
{
	const char *c;
	if (!strncmp(s, cmp, strlen(cmp))) {
		c = s + strlen(cmp);
		term_color(outbuf, cmp, COLOR_GRAY, 0, maxout);
		return c;
	}
	return NULL;
}

static void console_verboser(const char *s, int pos, int replace, int complete)
{
	char tmp[80];
	const char *c = NULL;
	/* Return to the beginning of the line */
	if (!pos) {
		fprintf(stdout, "\r");
		if ((c = fix_header(tmp, sizeof(tmp), s, VERBOSE_PREFIX_4)) ||
			(c = fix_header(tmp, sizeof(tmp), s, VERBOSE_PREFIX_3)) ||
			(c = fix_header(tmp, sizeof(tmp), s, VERBOSE_PREFIX_2)) ||
			(c = fix_header(tmp, sizeof(tmp), s, VERBOSE_PREFIX_1)))
			fputs(tmp, stdout);
	}
	if (c)
		fputs(c + pos,stdout);
	else
		fputs(s + pos,stdout);
	fflush(stdout);
	if (complete) {
		/* Wake up a poll()ing console */
		if (ast_opt_console && consolethread != AST_PTHREADT_NULL)
			pthread_kill(consolethread, SIGURG);
	}
}

static int ast_all_zeros(char *s)
{
	while (*s) {
		if (*s > 32)
			return 0;
		s++;  
	}
	return 1;
}

static void consolehandler(char *s)
{
	printf(term_end());
	fflush(stdout);
	/* Called when readline data is available */
	if (s && !ast_all_zeros(s))
		ast_el_add_history(s);
	/* Give the console access to the shell */
	if (s) {
		/* The real handler for bang */
		if (s[0] == '!') {
			if (s[1])
				ast_safe_system(s+1);
			else
				ast_safe_system(getenv("SHELL") ? getenv("SHELL") : "/bin/sh");
		} else 
		ast_cli_command(STDOUT_FILENO, s);
	} else
		fprintf(stdout, "\nUse \"quit\" to exit\n");
}

static int remoteconsolehandler(char *s)
{
	int ret = 0;
	/* Called when readline data is available */
	if (s && !ast_all_zeros(s))