Fixed unfreed memory and files handling errors

src/utils_op/utils.c

@@ -17,16 +17,18 @@ void err_msg(char *msg)
  * @param str2 
  * @return char* 
  */
-char *concat_to_front(char **str1, char *str2)
+char *prepend(char *dest, const char *prefix)
 {
-    char *tmp = strdup(*str1);
+    size_t orig_len = strlen(dest);
+    size_t prefix_len = strlen(prefix);
 
-    strcpy(*str1, str2);
-    strcat(*str1, tmp);
+    dest = realloc(dest, orig_len + prefix_len + 1);
+    
+    memmove(dest + prefix_len, dest, orig_len + 1);
 
-    free(tmp);
+    memcpy(dest, prefix, prefix_len);
 
-    return *str1;
+    return dest;
 }
 
 /**