pbx.c

	} else {
		context = NULL;
		exten = NULL;
	}
	ast_pthread_mutex_lock(&conlock);
	con = contexts;
	while(con) {
		if (!context || (!strcasecmp(context, con->name))) {
			ast_cli(fd, "\n [ Context '%s' created by '%s']\n", con->name, con->registrar);
			eroot = con->root;
			while(eroot) {
				if (!exten || (!strcasecmp(exten, eroot->exten))) {
					memset(tmp, ' ', sizeof(tmp));
					snprintf(tmp, sizeof(tmp), "  '%s' => ", eroot->exten);
					spaces = strlen(tmp);
					tmp[spaces] = ' ';
					if (spaces < 19)
						spaces = 19;
					snprintf(tmp2, sizeof(tmp2), "%d. %s(%s)", eroot->priority, eroot->app, (char *)eroot->data);
					snprintf(tmp + spaces, sizeof(tmp) - spaces,     "%-45s [%s]\n", 
							tmp2, eroot->registrar);
					ast_cli(fd, tmp);
					memset(tmp, ' ', spaces);
					e = eroot->peer;
					while(e) {
						snprintf(tmp2, sizeof(tmp2), "%d. %s(%s)", e->priority, e->app, (char *)e->data);
						snprintf(tmp + spaces, sizeof(tmp) - spaces,     "%-45s [%s]\n", 
							tmp2, e->registrar);
						ast_cli(fd, tmp);
						e = e->peer;
					}
				}
				eroot = eroot->next;
			}
			inc = con->includes;
			while(inc) {
				snprintf(tmp, sizeof(tmp), "   Include =>    '%s'", inc->name);
				ast_cli(fd, "%s [%s]\n", tmp, inc->registrar);
				inc = inc->next;
			}
		}
		con = con->next;
	}
	ast_pthread_mutex_unlock(&conlock);
	return RESULT_SUCCESS;
}

static struct ast_cli_entry showapps = { { "show", "applications", NULL }, 
	handle_show_applications, "Shows registered applications", apps_help };

static struct ast_cli_entry showdialplan = { { "show", "dialplan", NULL }, 
	handle_dialplan, "Displays all or part of dialplan", dialplan_help, complete_context };

static struct ast_cli_entry showapp = { { "show", "application", NULL }, 
	handle_show_application, "Describe a specific application", app_help, complete_app };
	
int ast_unregister_application(char *app) {
	struct ast_app *tmp, *tmpl = NULL;
	if (ast_pthread_mutex_lock(&applock)) {
		ast_log(LOG_ERROR, "Unable to lock application list\n");
		return -1;
	}
	tmp = apps;
	while(tmp) {
		if (!strcasecmp(app, tmp->name)) {
			if (tmpl)
				tmpl->next = tmp->next;
			else
				apps = tmp->next;
			if (option_verbose > 1)
				ast_verbose( VERBOSE_PREFIX_2 "Unregistered application '%s'\n", tmp->name);
			ast_pthread_mutex_unlock(&applock);
			return 0;
		}
		tmpl = tmp;
		tmp = tmp->next;
	}
	ast_pthread_mutex_unlock(&applock);
	return -1;
}

struct ast_context *ast_context_create(char *name, char *registrar)
{
	struct ast_context *tmp;
	
	ast_pthread_mutex_lock(&conlock);
	tmp = contexts;
	while(tmp) {
		if (!strcasecmp(tmp->name, name)) {
			ast_pthread_mutex_unlock(&conlock);
			ast_log(LOG_WARNING, "Tried to register context '%s', already in use\n", name);
			return NULL;
		}
		tmp = tmp->next;
	}
	tmp = malloc(sizeof(struct ast_context));
	if (tmp) {
		pthread_mutex_init(&tmp->lock, NULL);
		strncpy(tmp->name, name, sizeof(tmp->name));
		tmp->root = NULL;
		tmp->registrar = registrar;
		tmp->next = contexts;
		tmp->includes = NULL;
		contexts = tmp;
		if (option_debug)
			ast_log(LOG_DEBUG, "Registered context '%s'\n", tmp->name);
		else if (option_verbose > 2)
			ast_verbose( VERBOSE_PREFIX_3 "Registered extension context '%s'\n", tmp->name);
	} else
		ast_log(LOG_WARNING, "Out of memory\n");
	
	ast_pthread_mutex_unlock(&conlock);
	return tmp;
}

int ast_context_add_include2(struct ast_context *con, char *value, char *registrar)
{
	struct ast_include *inc, *incc, *incl = NULL;
	inc = malloc(sizeof(struct ast_include));
	if (!inc) {
		ast_log(LOG_WARNING, "Out of memory\n");
		return -1;
	}
	strncpy(inc->name, value, sizeof(inc->name));
	inc->next = NULL;
	inc->registrar = registrar;
	pthread_mutex_lock(&con->lock);
	incc = con->includes;
	while(incc) {
		incl = incc;
		if (!strcasecmp(incc->name, value)) {
			/* Already there */
			pthread_mutex_unlock(&con->lock);
			return 0;
		}
		incc = incc->next;
	}
	if (incl) 
		incl->next = inc;
	else
		con->includes = inc;
	pthread_mutex_unlock(&con->lock);
	return 0;
	
}

int ast_add_extension2(struct ast_context *con,
					  int replace, char *extension, int priority,
					  char *application, void *data, void (*datad)(void *),
					  char *registrar)
{

#define LOG { 	if (option_debug) \
		ast_log(LOG_DEBUG, "Added extension '%s' priority %d to %s\n", tmp->exten, tmp->priority, con->name); \
	else if (option_verbose > 2) \
		ast_verbose( VERBOSE_PREFIX_3 "Added extension '%s' priority %d to %s\n", tmp->exten, tmp->priority, con->name); \
		}

	/*
	 * This is a fairly complex routine.  Different extensions are kept
	 * in order by the extension number.  Then, extensions of different
	 * priorities (same extension) are kept in a list, according to the
	 * peer pointer.
	 */
	struct ast_exten *tmp, *e, *el = NULL, *ep = NULL;
	int res;
	/* Be optimistic:  Build the extension structure first */
	tmp = malloc(sizeof(struct ast_exten));
	if (tmp) {
		strncpy(tmp->exten, extension, sizeof(tmp->exten));
		tmp->priority = priority;
		strncpy(tmp->app, application, sizeof(tmp->app));
		tmp->data = data;
		tmp->datad = datad;
		tmp->registrar = registrar;
		tmp->peer = NULL;
		tmp->next =  NULL;
	} else {
		ast_log(LOG_WARNING, "Out of memory\n");
		return -1;
	}
	if (ast_pthread_mutex_lock(&con->lock)) {
		free(tmp);
		/* And properly destroy the data */
		datad(data);
		ast_log(LOG_WARNING, "Failed to lock context '%s'\n", con->name);
		return -1;
	}
	e = con->root;
	while(e) {
		res= strcasecmp(e->exten, extension);
		if (res == 0) {
			/* We have an exact match, now we find where we are
			   and be sure there's no duplicates */
			while(e) {
				if (e->priority == tmp->priority) {
					/* Can't have something exactly the same.  Is this a
					   replacement?  If so, replace, otherwise, bonk. */
					if (replace) {
						if (ep) {
							/* We're in the peer list, insert ourselves */
							ep->peer = tmp;
							tmp->peer = e->peer;
						} else if (el) {
							/* We're the first extension. Take over e's functions */
							el->next = tmp;
							tmp->next = e->next;
							tmp->peer = e->peer;
						} else {
							/* We're the very first extension.  */
							con->root = tmp;
							tmp->next = e->next;
							tmp->peer = e->peer;
						}
						/* Destroy the old one */
						e->datad(e->data);
						free(e);
						ast_pthread_mutex_unlock(&con->lock);
						/* And immediately return success. */
						LOG;
						return 0;
					} else {
						ast_log(LOG_WARNING, "Unable to register extension '%s', priority %d in '%s', already in use\n", tmp->exten, tmp->priority, con->name);
						tmp->datad(tmp->data);
						free(tmp);
						ast_pthread_mutex_unlock(&con->lock);
						return -1;
					}
				} else if (e->priority > tmp->priority) {
					/* Slip ourselves in just before e */
					if (ep) {
						/* Easy enough, we're just in the peer list */
						ep->peer = tmp;
						tmp->peer = e;
					} else if (el) {
						/* We're the first extension in this peer list */
						el->next = tmp;
						tmp->next = e->next;
						e->next = NULL;
						tmp->peer = e;
					} else {
						/* We're the very first extension altogether */
						tmp->next = con->root;
						/* Con->root must always exist or we couldn't get here */
						tmp->peer = con->root->peer;
						con->root = tmp;
					}
					ast_pthread_mutex_unlock(&con->lock);
					/* And immediately return success. */
					LOG;
					return 0;
				}
				ep = e;
				e = e->peer;
			}
			/* If we make it here, then it's time for us to go at the very end.
			   ep *must* be defined or we couldn't have gotten here. */
			ep->peer = tmp;
			ast_pthread_mutex_unlock(&con->lock);
			/* And immediately return success. */
			LOG;
			return 0;
				
		} else if (res > 0) {
			/* Insert ourselves just before 'e'.  We're the first extension of
			   this kind */
			tmp->next = e;
			if (el) {
				/* We're in the list somewhere */
				el->next = tmp;
			} else {
				/* We're at the top of the list */
				con->root = tmp;
			}
			ast_pthread_mutex_unlock(&con->lock);
			/* And immediately return success. */
			LOG;
			return 0;
		}			
			
		el = e;
		e = e->next;
	}
	/* If we fall all the way through to here, then we need to be on the end. */
	if (el)
		el->next = tmp;
	else
		con->root = tmp;
	ast_pthread_mutex_unlock(&con->lock);
	LOG;
	return 0;	
}

void ast_context_destroy(struct ast_context *con, char *registrar)
{
	struct ast_context *tmp, *tmpl=NULL;
	struct ast_include *tmpi, *tmpil= NULL;
	ast_pthread_mutex_lock(&conlock);
	tmp = contexts;
	while(tmp) {
		if (((tmp == con) || !con) &&
		    (!registrar || !strcasecmp(registrar, tmp->registrar))) {
			/* Okay, let's lock the structure to be sure nobody else
			   is searching through it. */
			if (ast_pthread_mutex_lock(&tmp->lock)) {
				ast_log(LOG_WARNING, "Unable to lock context lock\n");
				return;
			}
			if (tmpl)
				tmpl->next = tmp->next;
			else
				contexts = tmp->next;
			/* Okay, now we're safe to let it go -- in a sense, we were
			   ready to let it go as soon as we locked it. */
			ast_pthread_mutex_unlock(&tmp->lock);
			for (tmpi = tmp->includes; tmpi; ) {
				/* Free includes */
				tmpil = tmpi;
				tmpi = tmpi->next;
				free(tmpil);
				tmpil = tmpi;
			}
			free(tmp);
			if (!con) {
				/* Might need to get another one -- restart */
				tmp = contexts;
				tmpl = NULL;
				tmpil = NULL;
				continue;
			}
			ast_pthread_mutex_unlock(&conlock);
			return;
		}
		tmpl = tmp;
		tmp = tmp->next;
	}
	ast_pthread_mutex_unlock(&conlock);
}

static void wait_for_hangup(struct ast_channel *chan)
{
	int res;
	struct ast_frame *f;
	do {
		res = ast_waitfor(chan, -1);
		if (res < 0)
			return;
		f = ast_read(chan);
		if (f)
			ast_frfree(f);
	} while(f);
}

static int pbx_builtin_ringing(struct ast_channel *chan, void *data)
{
	ast_indicate(chan, AST_CONTROL_RINGING);
	return 0;
}

static int pbx_builtin_busy(struct ast_channel *chan, void *data)
{
	ast_indicate(chan, AST_CONTROL_BUSY);		
	wait_for_hangup(chan);
	return -1;
}

static int pbx_builtin_congestion(struct ast_channel *chan, void *data)
{
	ast_indicate(chan, AST_CONTROL_CONGESTION);
	wait_for_hangup(chan);
	return -1;
}

static int pbx_builtin_answer(struct ast_channel *chan, void *data)
{
	if (chan->state != AST_STATE_RING) {
		if (option_debug)
			ast_log(LOG_DEBUG, "Ignoring answer request since line is not ringing\n");
		return 0;
	} else
		return ast_answer(chan);
}

static int pbx_builtin_setlanguage(struct ast_channel *chan, void *data)
{
	/* Copy the language as specified */
	strncpy(chan->language, (char *)data, sizeof(chan->language));
	return 0;
}

static int pbx_builtin_hangup(struct ast_channel *chan, void *data)
{
	/* Just return non-zero and it will hang up */
	return -1;
}

static int pbx_builtin_stripmsd(struct ast_channel *chan, void *data)
{
	char newexten[AST_MAX_EXTENSION] = "";
	if (!data || !atoi(data)) {
		ast_log(LOG_DEBUG, "Ignoring, since number of digits to strip is 0\n");
		return 0;
	}
	if (strlen(chan->exten) > atoi(data)) {
		strncpy(newexten, chan->exten + atoi(data), sizeof(newexten));
	}
	strncpy(chan->exten, newexten, sizeof(chan->exten));
	return 0;
}

static int pbx_builtin_prefix(struct ast_channel *chan, void *data)
{
	char newexten[AST_MAX_EXTENSION] = "";
	if (!data || !strlen(data)) {
		ast_log(LOG_DEBUG, "Ignoring, since there is no prefix to add\n");
		return 0;
	}
	snprintf(newexten, sizeof(newexten), "%s%s", (char *)data, chan->exten);
	strncpy(chan->exten, newexten, sizeof(chan->exten));
	if (option_verbose > 2)
		ast_verbose(VERBOSE_PREFIX_3 "Prepended prefix, new extension is %s\n", chan->exten);
	return 0;
}

static int pbx_builtin_wait(struct ast_channel *chan, void *data)
{
	/* Wait for "n" seconds */
	if (data && atoi((char *)data))
		sleep(atoi((char *)data));
	return 0;
}

static int pbx_builtin_background(struct ast_channel *chan, void *data)
{
	int res;
	/* Answer if need be */
	if (chan->state != AST_STATE_UP)
		if (ast_answer(chan))
			return -1;
	/* Stop anything playing */
	ast_stopstream(chan);
	/* Stream a file */
	res = ast_streamfile(chan, (char *)data, chan->language);
	return res;
}

static int pbx_builtin_rtimeout(struct ast_channel *chan, void *data)
{
	/* Set the timeout for how long to wait between digits */
	chan->pbx->rtimeout = atoi((char *)data);
	if (option_verbose > 2)
		ast_verbose( VERBOSE_PREFIX_3 "Set Response Timeout to %d\n", chan->pbx->rtimeout);
	return 0;
}

static int pbx_builtin_dtimeout(struct ast_channel *chan, void *data)
{
	/* Set the timeout for how long to wait between digits */
	chan->pbx->dtimeout = atoi((char *)data);
	if (option_verbose > 2)
		ast_verbose( VERBOSE_PREFIX_3 "Set Digit Timeout to %d\n", chan->pbx->dtimeout);
	return 0;
}

static int pbx_builtin_goto(struct ast_channel *chan, void *data)
{
	char *s;
	char *exten, *pri, *context;
	if (!data) {
		ast_log(LOG_WARNING, "Goto requires an argument (optional context|optional extension|priority)\n");
		return -1;
	}
	s = strdup((void *) data);
	context = strtok(s, "|");
	exten = strtok(NULL, "|");
	if (!exten) {
		/* Only a priority in this one */
		pri = context;
		exten = NULL;
		context = NULL;
	} else {
		pri = strtok(NULL, "|");
		if (!pri) {
			/* Only an extension and priority in this one */
			pri = exten;
			exten = context;
			context = NULL;
		}
	}
	if (atoi(pri) < 0) {
		ast_log(LOG_WARNING, "Priority '%s' must be a number > 0\n", pri);
		free(s);
		return -1;
	}
	/* At this point we have a priority and maybe an extension and a context */
	chan->priority = atoi(pri) - 1;
	if (exten && strcasecmp(exten, "BYEXTENSION"))
		strncpy(chan->exten, exten, sizeof(chan->exten));
	if (context)
		strncpy(chan->context, context, sizeof(chan->context));
	if (option_verbose > 2)
		ast_verbose( VERBOSE_PREFIX_3 "Goto (%s,%s,%d)\n", chan->context,chan->exten, chan->priority+1);
	return 0;
}

int load_pbx(void)
{
	int x;
	/* Initialize the PBX */
	if (option_verbose) {
		ast_verbose( "Asterisk PBX Core Initializing\n");
		ast_verbose( "Registering builtin applications:\n");
	}
	ast_cli_register(&showapps);
	ast_cli_register(&showapp);
	ast_cli_register(&showdialplan);
	for (x=0;x<sizeof(builtins) / sizeof(struct pbx_builtin); x++) {
		if (option_verbose)
			ast_verbose( VERBOSE_PREFIX_1 "[%s]\n", builtins[x].name);
		if (ast_register_application(builtins[x].name, builtins[x].execute, builtins[x].synopsis, builtins[x].description)) {
			ast_log(LOG_ERROR, "Unable to register builtin application '%s'\n", builtins[x].name);
			return -1;
		}
	}
	return 0;
}