CURRENT_ROLE() function

3 files changed, 49 insertions, 7 deletions

diff --git a/sql/item_strfunc.cc b/sql/item_strfunc.cc
index 02d64952459..66fae0bed10 100644
--- a/sql/item_strfunc.cc
+++ b/sql/item_strfunc.cc
@@ -2332,16 +2332,28 @@ bool Item_func_current_user::fix_fields(THD *thd, Item **ref)
   if (Item_func_sysconst::fix_fields(thd, ref))
     return TRUE;
 
-  Security_context *ctx=
-#ifndef NO_EMBEDDED_ACCESS_CHECKS
-                         (context->security_ctx
-                          ? context->security_ctx : thd->security_ctx);
-#else
-                         thd->security_ctx;
-#endif /*NO_EMBEDDED_ACCESS_CHECKS*/
+  Security_context *ctx= context->security_ctx
+                          ? context->security_ctx : thd->security_ctx;
   return init(ctx->priv_user, ctx->priv_host);
 }
 
+bool Item_func_current_role::fix_fields(THD *thd, Item **ref)
+{
+  if (Item_func_sysconst::fix_fields(thd, ref))
+    return 1;
+
+  Security_context *ctx= context->security_ctx
+                          ? context->security_ctx : thd->security_ctx;
+
+  const char *role= ctx->priv_role[0] ? ctx->priv_role : NONE_ROLE;
+
+  if (str_value.copy(role, strlen(role), system_charset_info))
+    return 1;
+
+  str_value.mark_as_const();
+  return 0;
+}
+
 
 void Item_func_soundex::fix_length_and_dec()
 {
diff --git a/sql/item_strfunc.h b/sql/item_strfunc.h
index e09dee18d4f..8d9bda4902e 100644
--- a/sql/item_strfunc.h
+++ b/sql/item_strfunc.h
@@ -580,6 +580,28 @@ public:
 };
 
 
+class Item_func_current_role :public Item_func_sysconst
+{
+  Name_resolution_context *context;
+
+public:
+  Item_func_current_role(Name_resolution_context *context_arg)
+    : context(context_arg) {}
+  bool fix_fields(THD *thd, Item **ref);
+  void fix_length_and_dec()
+  { max_length= username_char_length * SYSTEM_CHARSET_MBMAXLEN; }
+  int save_in_field(Field *field, bool no_conversions)
+  { return save_str_value_in_field(field, &str_value); }
+  const char *func_name() const { return "current_role"; }
+  const char *fully_qualified_func_name() const { return "current_role()"; }
+  String *val_str(String *)
+  {
+    DBUG_ASSERT(fixed == 1);
+    return (null_value ? 0 : &str_value);
+  }
+};
+
+
 class Item_func_soundex :public Item_str_func
 {
   String tmp_value;
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index 38f9709f180..9ed7e8e8173 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -8648,6 +8648,14 @@ function_call_keyword:
             Lex->set_stmt_unsafe(LEX::BINLOG_STMT_UNSAFE_SYSTEM_FUNCTION);
             Lex->safe_to_cache_query= 0;
           }
+        | CURRENT_ROLE optional_braces
+          {
+            $$= new (thd->mem_root) Item_func_current_role(Lex->current_context());
+            if ($$ == NULL)
+              MYSQL_YYABORT;
+            Lex->set_stmt_unsafe(LEX::BINLOG_STMT_UNSAFE_SYSTEM_FUNCTION);
+            Lex->safe_to_cache_query= 0;
+          }
         | DATE_SYM '(' expr ')'
           {
             $$= new (thd->mem_root) Item_date_typecast($3);