when using moh files mode, don't look for a file past the number of files

that have been loaded, or worse, past the size of the files array


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@31776 65c4cc65-6c06-0410-ace0-fbb531ad65f3

res/res_musiconhold.c

@@ -218,6 +218,8 @@ static int ast_moh_files_next(struct ast_channel *chan)
 			if (ast_test_flag(state->class, MOH_RANDOMIZE))
 				state->pos = ast_random();
 
+			state->pos %= state->class->total_files;
+
 			/* check to see if this file's format can be opened */
 			if (ast_fileexists(state->class->filearray[state->pos], NULL, NULL) != -1)
 				break;