pbx.c

	while(tmp) {
		if (!strcasecmp(tmp->name, name)) {
			ast_mutex_unlock(&conlock);
			ast_log(LOG_WARNING, "Tried to register context '%s', already in use\n", name);
			if (!extcontexts)
				ast_mutex_unlock(&conlock);
			return NULL;
		}
		tmp = tmp->next;
	}
	tmp = malloc(length);
	if (tmp) {
		memset(tmp, 0, length);
		ast_mutex_init(&tmp->lock);
		strcpy(tmp->name, name);
		tmp->root = NULL;
		tmp->registrar = registrar;
		tmp->next = *local_contexts;
		tmp->includes = NULL;
		tmp->ignorepats = NULL;
		*local_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_ERROR, "Out of memory\n");
	
	if (!extcontexts)
		ast_mutex_unlock(&conlock);
	return tmp;
}

void __ast_context_destroy(struct ast_context *con, const char *registrar);

void ast_merge_contexts_and_delete(struct ast_context **extcontexts, const char *registrar) {
	struct ast_context *tmp, *lasttmp = NULL;
	tmp = *extcontexts;
	ast_mutex_lock(&conlock);
	if (registrar) {
		__ast_context_destroy(NULL,registrar);
		while (tmp) {
			lasttmp = tmp;
			tmp = tmp->next;
		}
	} else {
		while (tmp) {
			__ast_context_destroy(tmp,tmp->registrar);
			lasttmp = tmp;
			tmp = tmp->next;
		}
	}
	if (lasttmp) {
		lasttmp->next = contexts;
		contexts = *extcontexts;
		*extcontexts = NULL;
	} else 
		ast_log(LOG_WARNING, "Requested contexts didn't get merged\n");
	ast_mutex_unlock(&conlock);
	return;	
}

/*
 * errno values
 *  EBUSY  - can't lock
 *  ENOENT - no existence of context
 */
int ast_context_add_include(const char *context, const char *include, const char *registrar)
{
	struct ast_context *c;

	if (ast_lock_contexts()) {
		errno = EBUSY;
		return -1;
	}

	/* walk contexts ... */
	c = ast_walk_contexts(NULL);
	while (c) {
		/* ... search for the right one ... */
		if (!strcmp(ast_get_context_name(c), context)) {
			int ret = ast_context_add_include2(c, include, registrar);
			/* ... unlock contexts list and return */
			ast_unlock_contexts();
			return ret;
		}
		c = ast_walk_contexts(c);
	}

	/* we can't find the right context */
	ast_unlock_contexts();
	errno = ENOENT;
	return -1;
}

#define FIND_NEXT \
do { \
	c = info; \
	while(*c && (*c != '|')) c++; \
	if (*c) { *c = '\0'; c++; } else c = NULL; \
} while(0)

static void get_timerange(struct ast_include *i, char *times)
{
	char *e;
	int x;
	int s1, s2;
	int e1, e2;
	/*	int cth, ctm; */

	/* start disabling all times, fill the fields with 0's, as they may contain garbage */
	memset(i->minmask, 0, sizeof(i->minmask));
	
	/* Star is all times */
	if (ast_strlen_zero(times) || !strcmp(times, "*")) {
		for (x=0;x<24;x++)
			i->minmask[x] = (1 << 30) - 1;
		return;
	}
	/* Otherwise expect a range */
	e = strchr(times, '-');
	if (!e) {
		ast_log(LOG_WARNING, "Time range is not valid. Assuming no restrictions based on time.\n");
		return;
	}
	*e = '\0';
	e++;
	while(*e && !isdigit(*e)) e++;
	if (!*e) {
		ast_log(LOG_WARNING, "Invalid time range.  Assuming no restrictions based on time.\n");
		return;
	}
	if (sscanf(times, "%d:%d", &s1, &s2) != 2) {
		ast_log(LOG_WARNING, "%s isn't a time.  Assuming no restrictions based on time.\n", times);
		return;
	}
	if (sscanf(e, "%d:%d", &e1, &e2) != 2) {
		ast_log(LOG_WARNING, "%s isn't a time.  Assuming no restrictions based on time.\n", e);
		return;
	}

#if 1
	s1 = s1 * 30 + s2/2;
	if ((s1 < 0) || (s1 >= 24*30)) {
		ast_log(LOG_WARNING, "%s isn't a valid start time. Assuming no time.\n", times);
		return;
	}
	e1 = e1 * 30 + e2/2;
	if ((e1 < 0) || (e1 >= 24*30)) {
		ast_log(LOG_WARNING, "%s isn't a valid end time. Assuming no time.\n", e);
		return;
	}
	/* Go through the time and enable each appropriate bit */
	for (x=s1;x != e1;x = (x + 1) % (24 * 30)) {
		i->minmask[x/30] |= (1 << (x % 30));
	}
	/* Do the last one */
	i->minmask[x/30] |= (1 << (x % 30));
#else
	for (cth=0;cth<24;cth++) {
		/* Initialize masks to blank */
		i->minmask[cth] = 0;
		for (ctm=0;ctm<30;ctm++) {
			if (
			/* First hour with more than one hour */
			      (((cth == s1) && (ctm >= s2)) &&
			       ((cth < e1)))
			/* Only one hour */
			||    (((cth == s1) && (ctm >= s2)) &&
			       ((cth == e1) && (ctm <= e2)))
			/* In between first and last hours (more than 2 hours) */
			||    ((cth > s1) &&
			       (cth < e1))
			/* Last hour with more than one hour */
			||    ((cth > s1) &&
			       ((cth == e1) && (ctm <= e2)))
			)
				i->minmask[cth] |= (1 << (ctm / 2));
		}
	}
#endif
	/* All done */
	return;
}

static char *days[] =
{
	"sun",
	"mon",
	"tue",
	"wed",
	"thu",
	"fri",
	"sat",
};

static unsigned int get_dow(char *dow)
{
	char *c;
	/* The following line is coincidence, really! */
	int s, e, x;
	unsigned int mask;

	/* Check for all days */
	if (ast_strlen_zero(dow) || !strcmp(dow, "*"))
		return (1 << 7) - 1;
	/* Get start and ending days */
	c = strchr(dow, '-');
	if (c) {
		*c = '\0';
		c++;
	} else
		c = NULL;
	/* Find the start */
	s = 0;
	while((s < 7) && strcasecmp(dow, days[s])) s++;
	if (s >= 7) {
		ast_log(LOG_WARNING, "Invalid day '%s', assuming none\n", dow);
		return 0;
	}
	if (c) {
		e = 0;
		while((e < 7) && strcasecmp(c, days[e])) e++;
		if (e >= 7) {
			ast_log(LOG_WARNING, "Invalid day '%s', assuming none\n", c);
			return 0;
		}
	} else
		e = s;
	mask = 0;
	for (x=s; x != e; x = (x + 1) % 7) {
		mask |= (1 << x);
	}
	/* One last one */
	mask |= (1 << x);
	return mask;
}

static unsigned int get_day(char *day)
{
	char *c;
	/* The following line is coincidence, really! */
	int s, e, x;
	unsigned int mask;

	/* Check for all days */
	if (ast_strlen_zero(day) || !strcmp(day, "*")) {
		mask = (1 << 30)  + ((1 << 30) - 1);
		return mask;
	}
	/* Get start and ending days */
	c = strchr(day, '-');
	if (c) {
		*c = '\0';
		c++;
	}
	/* Find the start */
	if (sscanf(day, "%d", &s) != 1) {
		ast_log(LOG_WARNING, "Invalid day '%s', assuming none\n", day);
		return 0;
	}
	if ((s < 1) || (s > 31)) {
		ast_log(LOG_WARNING, "Invalid day '%s', assuming none\n", day);
		return 0;
	}
	s--;
	if (c) {
		if (sscanf(c, "%d", &e) != 1) {
			ast_log(LOG_WARNING, "Invalid day '%s', assuming none\n", c);
			return 0;
		}
		if ((e < 1) || (e > 31)) {
			ast_log(LOG_WARNING, "Invalid day '%s', assuming none\n", c);
			return 0;
		}
		e--;
	} else
		e = s;
	mask = 0;
	for (x=s;x!=e;x = (x + 1) % 31) {
		mask |= (1 << x);
	}
	mask |= (1 << x);
	return mask;
}

static char *months[] =
{
	"jan",
	"feb",
	"mar",
	"apr",
	"may",
	"jun",
	"jul",
	"aug",
	"sep",
	"oct",
	"nov",
	"dec",
};

static unsigned int get_month(char *mon)
{
	char *c;
	/* The following line is coincidence, really! */
	int s, e, x;
	unsigned int mask;

	/* Check for all days */
	if (ast_strlen_zero(mon) || !strcmp(mon, "*")) 
		return (1 << 12) - 1;
	/* Get start and ending days */
	c = strchr(mon, '-');
	if (c) {
		*c = '\0';
		c++;
	}
	/* Find the start */
	s = 0;
	while((s < 12) && strcasecmp(mon, months[s])) s++;
	if (s >= 12) {
		ast_log(LOG_WARNING, "Invalid month '%s', assuming none\n", mon);
		return 0;
	}
	if (c) {
		e = 0;
		while((e < 12) && strcasecmp(mon, months[e])) e++;
		if (e >= 12) {
			ast_log(LOG_WARNING, "Invalid month '%s', assuming none\n", c);
			return 0;
		}
	} else
		e = s;
	mask = 0;
	for (x=s; x!=e; x = (x + 1) % 12) {
		mask |= (1 << x);
	}
	/* One last one */
	mask |= (1 << x);
	return mask;
}

static void build_timing(struct ast_include *i, char *info)
{
	char *c;

	/* Check for empty just in case */
	if (ast_strlen_zero(info))
		return;
	i->hastime = 1;
	/* Assume everything except time */
	i->monthmask = (1 << 12) - 1;
	i->daymask = (1 << 30) - 1 + (1 << 30);
	i->dowmask = (1 << 7) - 1;
	/* Avoid using str tok */
	FIND_NEXT;
	/* Info has the time range, start with that */
	get_timerange(i, info);
	info = c;
	if (!info)
		return;
	FIND_NEXT;
	/* Now check for day of week */
	i->dowmask = get_dow(info);

	info = c;
	if (!info)
		return;
	FIND_NEXT;
	/* Now check for the day of the month */
	i->daymask = get_day(info);
	info = c;
	if (!info)
		return;
	FIND_NEXT;
	/* And finally go for the month */
	i->monthmask = get_month(info);
}

/*
 * errno values
 *  ENOMEM - out of memory
 *  EBUSY  - can't lock
 *  EEXIST - already included
 *  EINVAL - there is no existence of context for inclusion
 */
int ast_context_add_include2(struct ast_context *con, const char *value,
	const char *registrar)
{
	struct ast_include *new_include;
	char *c;
	struct ast_include *i, *il = NULL; /* include, include_last */
	int length;
	char *p;
	
	length = sizeof(struct ast_include);
	length += 2 * (strlen(value) + 1);

	/* allocate new include structure ... */
	if (!(new_include = malloc(length))) {
		ast_log(LOG_ERROR, "Out of memory\n");
		errno = ENOMEM;
		return -1;
	}
	
	/* ... fill in this structure ... */
	memset(new_include, 0, length);
	p = new_include->stuff;
	new_include->name = p;
	strcpy(new_include->name, value);
	p += strlen(value) + 1;
	new_include->rname = p;
	strcpy(new_include->rname, value);
	c = new_include->rname;
	/* Strip off timing info */
	while(*c && (*c != '|')) c++; 
	/* Process if it's there */
	if (*c) {
		build_timing(new_include, c+1);
		*c = '\0';
	}
	new_include->next      = NULL;
	new_include->registrar = registrar;

	/* ... try to lock this context ... */
	if (ast_mutex_lock(&con->lock)) {
		free(new_include);
		errno = EBUSY;
		return -1;
	}

	/* ... go to last include and check if context is already included too... */
	i = con->includes;
	while (i) {
		if (!strcasecmp(i->name, new_include->name)) {
			free(new_include);
			ast_mutex_unlock(&con->lock);
			errno = EEXIST;
			return -1;
		}
		il = i;
		i = i->next;
	}

	/* ... include new context into context list, unlock, return */
	if (il)
		il->next = new_include;
	else
		con->includes = new_include;
	if (option_verbose > 2)
		ast_verbose(VERBOSE_PREFIX_3 "Including context '%s' in context '%s'\n", new_include->name, ast_get_context_name(con)); 
	ast_mutex_unlock(&con->lock);

	return 0;
}

/*
 * errno values
 *  EBUSY  - can't lock
 *  ENOENT - no existence of context
 */
int ast_context_add_switch(const char *context, const char *sw, const char *data, const char *registrar)
{
	struct ast_context *c;

	if (ast_lock_contexts()) {
		errno = EBUSY;
		return -1;
	}

	/* walk contexts ... */
	c = ast_walk_contexts(NULL);
	while (c) {
		/* ... search for the right one ... */
		if (!strcmp(ast_get_context_name(c), context)) {
			int ret = ast_context_add_switch2(c, sw, data, registrar);
			/* ... unlock contexts list and return */
			ast_unlock_contexts();
			return ret;
		}
		c = ast_walk_contexts(c);
	}

	/* we can't find the right context */
	ast_unlock_contexts();
	errno = ENOENT;
	return -1;
}

/*
 * errno values
 *  ENOMEM - out of memory
 *  EBUSY  - can't lock
 *  EEXIST - already included
 *  EINVAL - there is no existence of context for inclusion
 */
int ast_context_add_switch2(struct ast_context *con, const char *value,
	const char *data, const char *registrar)
{
	struct ast_sw *new_sw;
	struct ast_sw *i, *il = NULL; /* sw, sw_last */
	int length;
	char *p;
	
	length = sizeof(struct ast_sw);
	length += strlen(value) + 1;
	if (data)
		length += strlen(data);
	length++;

	/* allocate new sw structure ... */
	if (!(new_sw = malloc(length))) {
		ast_log(LOG_ERROR, "Out of memory\n");
		errno = ENOMEM;
		return -1;
	}
	
	/* ... fill in this structure ... */
	memset(new_sw, 0, length);
	p = new_sw->stuff;
	new_sw->name = p;
	strcpy(new_sw->name, value);
	p += strlen(value) + 1;
	new_sw->data = p;
	if (data)
		strcpy(new_sw->data, data);
	else
		strcpy(new_sw->data, "");
	new_sw->next      = NULL;
	new_sw->registrar = registrar;

	/* ... try to lock this context ... */
	if (ast_mutex_lock(&con->lock)) {
		free(new_sw);
		errno = EBUSY;
		return -1;
	}

	/* ... go to last sw and check if context is already swd too... */
	i = con->alts;
	while (i) {
		if (!strcasecmp(i->name, new_sw->name) && !strcasecmp(i->data, new_sw->data)) {
			free(new_sw);
			ast_mutex_unlock(&con->lock);
			errno = EEXIST;
			return -1;
		}
		il = i;
		i = i->next;
	}

	/* ... sw new context into context list, unlock, return */
	if (il)
		il->next = new_sw;
	else
		con->alts = new_sw;
	if (option_verbose > 2)
		ast_verbose(VERBOSE_PREFIX_3 "Including switch '%s/%s' in context '%s'\n", new_sw->name, new_sw->data, ast_get_context_name(con)); 
	ast_mutex_unlock(&con->lock);

	return 0;
}

/*
 * EBUSY  - can't lock
 * ENOENT - there is not context existence
 */
int ast_context_remove_ignorepat(const char *context, const char *ignorepat, const char *registrar)
{
	struct ast_context *c;

	if (ast_lock_contexts()) {
		errno = EBUSY;
		return -1;
	}

	c = ast_walk_contexts(NULL);
	while (c) {
		if (!strcmp(ast_get_context_name(c), context)) {
			int ret = ast_context_remove_ignorepat2(c, ignorepat, registrar);
			ast_unlock_contexts();
			return ret;
		}
		c = ast_walk_contexts(c);
	}

	ast_unlock_contexts();
	errno = ENOENT;
	return -1;
}

int ast_context_remove_ignorepat2(struct ast_context *con, const char *ignorepat, const char *registrar)
{
	struct ast_ignorepat *ip, *ipl = NULL;

	if (ast_mutex_lock(&con->lock)) {
		errno = EBUSY;
		return -1;
	}

	ip = con->ignorepats;
	while (ip) {
		if (!strcmp(ip->pattern, ignorepat) &&
			(!registrar || (registrar == ip->registrar))) {
			if (ipl) {
				ipl->next = ip->next;
				free(ip);
			} else {
				con->ignorepats = ip->next;
				free(ip);
			}
			ast_mutex_unlock(&con->lock);
			return 0;
		}
		ipl = ip; ip = ip->next;
	}

	ast_mutex_unlock(&con->lock);
	errno = EINVAL;
	return -1;
}

/*
 * EBUSY - can't lock
 * ENOENT - there is no existence of context
 */
int ast_context_add_ignorepat(const char *con, const char *value, const char *registrar)
{
	struct ast_context *c;

	if (ast_lock_contexts()) {
		errno = EBUSY;
		return -1;
	}

	c = ast_walk_contexts(NULL);
	while (c) {
		if (!strcmp(ast_get_context_name(c), con)) {
			int ret = ast_context_add_ignorepat2(c, value, registrar);
			ast_unlock_contexts();
			return ret;
		} 
		c = ast_walk_contexts(c);
	}

	ast_unlock_contexts();
	errno = ENOENT;
	return -1;
}

int ast_context_add_ignorepat2(struct ast_context *con, const char *value, const char *registrar)
{
	struct ast_ignorepat *ignorepat, *ignorepatc, *ignorepatl = NULL;
	int length;
	length = sizeof(struct ast_ignorepat);
	length += strlen(value) + 1;
	ignorepat = malloc(length);
	if (!ignorepat) {
		ast_log(LOG_ERROR, "Out of memory\n");
		errno = ENOMEM;
		return -1;
	}
	memset(ignorepat, 0, length);
	strcpy(ignorepat->pattern, value);
	ignorepat->next = NULL;
	ignorepat->registrar = registrar;
	ast_mutex_lock(&con->lock);
	ignorepatc = con->ignorepats;
	while(ignorepatc) {
		ignorepatl = ignorepatc;
		if (!strcasecmp(ignorepatc->pattern, value)) {
			/* Already there */
			ast_mutex_unlock(&con->lock);
			errno = EEXIST;
			return -1;
		}
		ignorepatc = ignorepatc->next;
	}
	if (ignorepatl) 
		ignorepatl->next = ignorepat;
	else
		con->ignorepats = ignorepat;
	ast_mutex_unlock(&con->lock);
	return 0;
	
}

int ast_ignore_pattern(const char *context, const char *pattern)
{
	struct ast_context *con;
	struct ast_ignorepat *pat;

	con = ast_context_find(context);
	if (con) {
		pat = con->ignorepats;
		while (pat) {
			if (ast_extension_match(pat->pattern, pattern))
				return 1;
			pat = pat->next;
		}
	} 
	return 0;
}

/*
 * EBUSY   - can't lock
 * ENOENT  - no existence of context
 *
 */
int ast_add_extension(const char *context, int replace, const char *extension, int priority, const char *label, const char *callerid,
	const char *application, void *data, void (*datad)(void *), const char *registrar)
{
	struct ast_context *c;

	if (ast_lock_contexts()) {
		errno = EBUSY;
		return -1;
	}

	c = ast_walk_contexts(NULL);
	while (c) {
		if (!strcmp(context, ast_get_context_name(c))) {
			int ret = ast_add_extension2(c, replace, extension, priority, label, callerid,
				application, data, datad, registrar);
			ast_unlock_contexts();
			return ret;
		}
		c = ast_walk_contexts(c);
	}

	ast_unlock_contexts();
	errno = ENOENT;
	return -1;
}

int ast_async_goto(struct ast_channel *chan, const char *context, const char *exten, int priority)
{
	int res = 0;
	ast_mutex_lock(&chan->lock);

	if (chan->pbx) {
		/* This channel is currently in the PBX */
		if (context && !ast_strlen_zero(context))
			strncpy(chan->context, context, sizeof(chan->context) - 1);
		if (exten && !ast_strlen_zero(exten))
			strncpy(chan->exten, exten, sizeof(chan->context) - 1);
		if (priority)
			chan->priority = priority - 1;
		ast_softhangup_nolock(chan, AST_SOFTHANGUP_ASYNCGOTO);
	} else {
		/* In order to do it when the channel doesn't really exist within
		   the PBX, we have to make a new channel, masquerade, and start the PBX
		   at the new location */
		struct ast_channel *tmpchan;
		tmpchan = ast_channel_alloc(0);
		if (tmpchan) {
			snprintf(tmpchan->name, sizeof(tmpchan->name), "AsyncGoto/%s", chan->name);
			ast_setstate(tmpchan, chan->_state);
			/* Make formats okay */
			tmpchan->readformat = chan->readformat;
			tmpchan->writeformat = chan->writeformat;
			/* Setup proper location */
			if (context && !ast_strlen_zero(context))
				strncpy(tmpchan->context, context, sizeof(tmpchan->context) - 1);
			else
				strncpy(tmpchan->context, chan->context, sizeof(tmpchan->context) - 1);
			if (exten && !ast_strlen_zero(exten))
				strncpy(tmpchan->exten, exten, sizeof(tmpchan->exten) - 1);
			else
				strncpy(tmpchan->exten, chan->exten, sizeof(tmpchan->exten) - 1);
			if (priority)
				tmpchan->priority = priority;
			else
				tmpchan->priority = chan->priority;
			
			/* Masquerade into temp channel */
			ast_channel_masquerade(tmpchan, chan);
		
			/* Grab the locks and get going */
			ast_mutex_lock(&tmpchan->lock);
			ast_do_masquerade(tmpchan);
			ast_mutex_unlock(&tmpchan->lock);
			/* Start the PBX going on our stolen channel */
			if (ast_pbx_start(tmpchan)) {
				ast_log(LOG_WARNING, "Unable to start PBX on %s\n", tmpchan->name);
				ast_hangup(tmpchan);
				res = -1;
			}
		} else {
			res = -1;
		}
	}
	ast_mutex_unlock(&chan->lock);
	return res;
}

int ast_async_goto_by_name(const char *channame, const char *context, const char *exten, int priority)
{
	struct ast_channel *chan;
	int res = -1;

	chan = ast_channel_walk_locked(NULL);
	while(chan) {
		if (!strcasecmp(channame, chan->name))
			break;
		ast_mutex_unlock(&chan->lock);
		chan = ast_channel_walk_locked(chan);
	}
	
	if (chan) {
		res = ast_async_goto(chan, context, exten, priority);
		ast_mutex_unlock(&chan->lock);
	}
	return res;
}

static void ext_strncpy(char *dst, const char *src, int len)
{
	int count=0;

	while(*src && (count < len - 1)) {
		switch(*src) {
		case ' ':
			/*	otherwise exten => [a-b],1,... doesn't work */
			/*		case '-': */
			/* Ignore */
			break;
		default:
			*dst = *src;
			dst++;
		}
		src++;
		count++;
	}
	*dst = '\0';
}

/*
 * EBUSY - can't lock
 * EEXIST - extension with the same priority exist and no replace is set
 *
 */
int ast_add_extension2(struct ast_context *con,
					  int replace, const char *extension, int priority, const char *label, const char *callerid,
					  const char *application, void *data, void (*datad)(void *),
					  const char *registrar)
{

#define LOG do { 	if (option_debug) {\
		if (tmp->matchcid) { \
			ast_log(LOG_DEBUG, "Added extension '%s' priority %d (CID match '%s') to %s\n", tmp->exten, tmp->priority, tmp->cidmatch, con->name); \
		} else { \
			ast_log(LOG_DEBUG, "Added extension '%s' priority %d to %s\n", tmp->exten, tmp->priority, con->name); \
		} \
	} else if (option_verbose > 2) { \
		if (tmp->matchcid) { \
			ast_verbose( VERBOSE_PREFIX_3 "Added extension '%s' priority %d (CID match '%s')to %s\n", tmp->exten, tmp->priority, tmp->cidmatch, con->name); \
		} else {  \
			ast_verbose( VERBOSE_PREFIX_3 "Added extension '%s' priority %d to %s\n", tmp->exten, tmp->priority, con->name); \
		} \
	} } while(0)

	/*
	 * 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;
	int length;
	char *p;
	length = sizeof(struct ast_exten);
	length += strlen(extension) + 1;
	length += strlen(application) + 1;
	if (label)
		length += strlen(label) + 1;
	if (callerid)
		length += strlen(callerid) + 1;
	else
		length ++;

	/* Be optimistic:  Build the extension structure first */
	tmp = malloc(length);
	if (tmp) {
		memset(tmp, 0, length);
		p = tmp->stuff;
		if (label) {
			tmp->label = p;
			strcpy(tmp->label, label);
			p += strlen(label) + 1;
		}
		tmp->exten = p;
		ext_strncpy(tmp->exten, extension, strlen(extension) + 1);
		p += strlen(extension) + 1;
		tmp->priority = priority;
		tmp->cidmatch = p;
		if (callerid) {
			ext_strncpy(tmp->cidmatch, callerid, strlen(callerid) + 1);
			p += strlen(callerid) + 1;
			tmp->matchcid = 1;
		} else {
			tmp->cidmatch[0] = '\0';
			tmp->matchcid = 0;
			p++;
		}
		tmp->app = p;
		strcpy(tmp->app, application);
		tmp->parent = con;
		tmp->data = data;
		tmp->datad = datad;
		tmp->registrar = registrar;
		tmp->peer = NULL;
		tmp->next =  NULL;
	} else {
		ast_log(LOG_ERROR, "Out of memory\n");
		errno = ENOMEM;
		return -1;
	}
	if (ast_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);
		errno = EBUSY;
		return -1;
	}
	e = con->root;
	while(e) {
		/* Make sure patterns are always last! */
		if ((e->exten[0] != '_') && (extension[0] == '_'))
			res = -1;
		else if ((e->exten[0] == '_') && (extension[0] != '_'))
			res = 1;
		else
			res= strcmp(e->exten, extension);
		if (!res) {
			if (!e->matchcid && !tmp->matchcid)
				res = 0;
			else if (tmp->matchcid && !e->matchcid)
				res = 1;
			else if (e->matchcid && !tmp->matchcid)
				res = -1;
			else
				res = strcasecmp(e->cidmatch, tmp->cidmatch);
		}
		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;
						}
						if (tmp->priority == PRIORITY_HINT)
						    ast_change_hint(e,tmp);
						/* Destroy the old one */
						e->datad(e->data);
						free(e);
						ast_mutex_unlock(&con->lock);
						if (tmp->priority == PRIORITY_HINT)
						    ast_change_hint(e, tmp);
						/* 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_mutex_unlock(&con->lock);
						errno = EEXIST;
						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;