fixing some warning

programs/util.c

@@ -296,7 +296,7 @@ void UTIL_freeFileNamesTable(FileNamesTable* table) {
       free(table->fileNames);
     }
 
-    if(table->buf) {
+    if(table && table->buf) {
       free(table->buf);
     }
 

programs/util.h

@@ -151,8 +151,8 @@ int UTIL_readLineFromFile(char* buf, size_t len, FILE* file);
 /*Note: tableSize is denotes the total capacity of table*/
 typedef struct
 {
-    const char** fileNames;
+    const char** fileNames = NULL;
-    char* buf;
+    char* buf = NULL;
     size_t tableSize;
 } FileNamesTable;