fix segfaults on bad api command usage MODAPP-34

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@6010 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/mod/applications/mod_commands/mod_commands.c

@@ -333,6 +333,11 @@ SWITCH_STANDARD_API(tone_detect_session_function)
 	time_t to = 0;
 	switch_core_session_t *rsession;
 	
+	if (!cmd) {
+		stream->write_function(stream, "USAGE: %s\n", TONE_DETECT_SYNTAX);
+		return SWITCH_STATUS_SUCCESS;
+	}
+
 	mydata = strdup(cmd);
 	assert(mydata != NULL);
 
@@ -990,6 +995,11 @@ SWITCH_STANDARD_API(sched_del_function)
 {
 	uint32_t cnt = 0;
 
+	if (!cmd) {
+		stream->write_function(stream, "Invalid syntax\n");
+		return SWITCH_STATUS_SUCCESS;
+	}
+	
 	if (switch_is_digit_string(cmd)) {
 		int64_t tmp;
 		tmp = (uint32_t) atoi(cmd);
@@ -1011,6 +1021,11 @@ SWITCH_STANDARD_API(xml_wrap_api_function)
 	switch_stream_handle_t mystream = { 0 };
 	int encoded = 0, elen = 0;
 
+	if (!cmd) {
+		stream->write_function(stream, "Invalid syntax\n");
+		return SWITCH_STATUS_SUCCESS;
+	}
+	
 	if ((dcommand = strdup(cmd))) {
 		if (!strncasecmp(dcommand, "encoded ", 8)) {
 			encoded++;
@@ -1059,7 +1074,10 @@ SWITCH_STANDARD_API(sched_api_function)
 	char *tm = NULL, *dcmd, *group;
 	time_t when;
 
-	assert(cmd != NULL);
+	if (!cmd) {
+		stream->write_function(stream, "Invalid syntax\n");
+		return SWITCH_STATUS_SUCCESS;
+	}
 	tm = strdup(cmd);
 	assert(tm != NULL);