YIN parser BUGFIX store parsed keyword id in extension substatements

TODO substatements still are not correctly parsed since their arguments
are stored as attribute substatements instead of getting them (for the
known statements) and storing them as the statement's argument value.
diff --git a/src/parser_yin.c b/src/parser_yin.c
index 7a36abe..a44d252 100644
--- a/src/parser_yin.c
+++ b/src/parser_yin.c
@@ -3183,8 +3183,7 @@
                     /* end of extension instance reached */
                     break;
                 }
-                LY_CHECK_RET(yin_parse_element_generic(ctx, name2fname(name, prefix_len),
-                                                       len2flen(name_len, prefix_len), data, &new_subelem));
+                LY_CHECK_RET(yin_parse_element_generic(ctx, name, name_len, prefix, prefix_len, data, &new_subelem));
                 if (!e->child) {
                     e->child = new_subelem;
                 } else {
@@ -3211,24 +3210,27 @@
 }
 
 LY_ERR
-yin_parse_element_generic(struct yin_parser_ctx *ctx, const char *name, size_t name_len, const char **data,
+yin_parse_element_generic(struct yin_parser_ctx *ctx, const char *name, size_t name_len, const char *prefix, size_t prefix_len, const char **data,
                           struct lysp_stmt **element)
 {
     LY_ERR ret = LY_SUCCESS;
     const char *temp_prefix, *temp_name;
     char *out = NULL;
-    size_t out_len, temp_name_len, temp_prefix_len, prefix_len;
+    size_t out_len, temp_name_len, temp_prefix_len;
     int dynamic;
     struct lysp_stmt *last = NULL, *new = NULL;
 
     /* allocate new structure for element */
     *element = calloc(1, sizeof(**element));
     LY_CHECK_ERR_RET(!(*element), LOGMEM(ctx->xml_ctx.ctx), LY_EMEM);
-    (*element)->stmt = lydict_insert(ctx->xml_ctx.ctx, name, name_len);
+    (*element)->stmt = lydict_insert(ctx->xml_ctx.ctx, prefix ? prefix : name, 0);
     LY_CHECK_RET(!(*element)->stmt, LY_EMEM);
+    /* TODO map prefix to module name */
+    (*element)->kw = yin_match_keyword(ctx, name, name_len, prefix, prefix_len, LY_STMT_EXTENSION_INSTANCE);
 
     last = (*element)->child;
-    /* load attributes */
+    /* load attributes - TODO in case of non-extension keyword, the argument details are known,
+     * so the argument can be stored correctly instead of storing pure attributes */
     while(ctx->xml_ctx.status == LYXML_ATTRIBUTE) {
         /* add new element to linked-list */
         new = calloc(1, sizeof(*last));
@@ -3242,9 +3244,10 @@
         last = new;
 
         last->flags |= LYS_YIN_ATTR;
-        LY_CHECK_RET(lyxml_get_attribute(&ctx->xml_ctx, data, &temp_prefix, &prefix_len, &temp_name, &temp_name_len));
+        LY_CHECK_RET(lyxml_get_attribute(&ctx->xml_ctx, data, &temp_prefix, &temp_prefix_len, &temp_name, &temp_name_len));
         last->stmt = lydict_insert(ctx->xml_ctx.ctx, temp_name, temp_name_len);
         LY_CHECK_RET(!last->stmt, LY_EMEM);
+        last->kw = yin_match_keyword(ctx, temp_name, temp_name_len, temp_prefix, temp_prefix_len, LY_STMT_EXTENSION_INSTANCE);
 
         LY_CHECK_RET(lyxml_get_string(&ctx->xml_ctx, data, &out, &out_len, &out, &out_len, &dynamic));
         /* attributes with prefix are ignored */
@@ -3269,8 +3272,7 @@
                     /* end of element reached */
                     break;
                 }
-                LY_CHECK_RET(yin_parse_element_generic(ctx, name2fname(temp_name, temp_prefix_len),
-                                                       len2flen(temp_name_len, temp_prefix_len), data, &new));
+                LY_CHECK_RET(yin_parse_element_generic(ctx, temp_name, temp_name_len, temp_prefix, temp_prefix_len, data, &new));
                 if (!(*element)->child) {
                     /* save first */
                     (*element)->child = new;
@@ -3288,7 +3290,7 @@
             }
 
             /* read closing tag */
-            LY_CHECK_RET(lyxml_get_element(&ctx->xml_ctx, data, &temp_prefix, &prefix_len, &temp_name, &temp_name_len));
+            LY_CHECK_RET(lyxml_get_element(&ctx->xml_ctx, data, &temp_prefix, &temp_prefix_len, &temp_name, &temp_name_len));
         }
     }