04_monitor_variable.diff

--- a/asterisk/res/res_monitor.c	2021-01-17 15:58:27.363015840 +0100
+++ b/asterisk/res/res_monitor.c	2021-01-17 16:21:11.665191216 +0100
@@ -646,10 +646,18 @@
 		/* if previous monitor file existed in a subdirectory, the directory will not be removed */
 		unlink(ast_channel_monitor(chan)->filename_base);
 
+		if (ast_strings_match(tmpstring, "regex", "^.*wewnetrzne.*$")) {
+	                ast_verbose("Monitor filename %s NOT changed to %s\n", ast_channel_monitor(chan)->filename_base, tmpstring);
+			doexit = 1;	
+		};        
+        
 		if (doexit) {
 			UNLOCK_IF_NEEDED(chan, need_lock);
 			return 0;
 		}
+		
+		pbx_builtin_setvar_helper(chan, "MONITOR_ORIG",ast_channel_monitor(chan)->filename_base);
+		ast_verbose("Monitor filename %s changed to %s\n", ast_channel_monitor(chan)->filename_base, tmpstring);
 
 		ast_copy_string(ast_channel_monitor(chan)->filename_base, tmpstring, sizeof(ast_channel_monitor(chan)->filename_base));
 		ast_channel_monitor(chan)->filename_changed = 1;