tree schema CHANGE modify extension structures to be compatible with input in YIN format
diff --git a/src/tree_schema.h b/src/tree_schema.h
index f5ddc35..65321eb 100644
--- a/src/tree_schema.h
+++ b/src/tree_schema.h
@@ -123,19 +123,20 @@
     const char *arg;                 /**< statement's argument */
     struct lysp_stmt *next;          /**< link to the next statement */
     struct lysp_stmt *child;         /**< list of the statement's substatements (linked list) */
-    uint16_t flags;
+    uint16_t flags;                  /**<  */
 };
-
+#define LYS_YIN 0x1;
 /**
  * @brief YANG extension instance
  */
 struct lysp_ext_instance {
-    const char *name;                /**< extension identifier, including possible prefix */
-    const char *argument;            /**< optional value of the extension's argument */
-    struct lysp_stmt *child;         /**< list of the extension's substatements (linked list) */
-    LYEXT_SUBSTMT insubstmt;         /**< value identifying placement of the extension instance */
-    uint32_t insubstmt_index;        /**< in case the instance is in a substatement, this identifies
-                                          the index of that substatement */
+    const char *name;                       /**< extension identifier, including possible prefix */
+    const char *argument;                   /**< optional value of the extension's argument */
+    struct lysp_stmt *child;                /**< list of the extension's substatements (linked list) */
+    LYEXT_SUBSTMT insubstmt;                /**< value identifying placement of the extension instance */
+    uint32_t insubstmt_index;               /**< in case the instance is in a substatement, this identifies
+                                                 the index of that substatement */
+    uint8_t yin;                            /** flag for YIN source format */
 };
 
 /**
@@ -528,6 +529,8 @@
 #define LYS_SINGLEQUOTED 0x100       /**< flag for single-quoted argument of an extension instance's substatement */
 #define LYS_DOUBLEQUOTED 0x200       /**< flag for double-quoted argument of an extension instance's substatement */
 
+#define LYS_YIN_ATTR     0x1000      /**< flag to identify YIN attribute */
+
 #define LYS_ISENUM       0x200       /**< flag to simply distinguish type in struct lysc_type_bitenum_item */
 
 #define LYS_FLAGS_COMPILED_MASK 0xff /**< mask for flags that maps to the compiled structures */