Refactored yacc grammar to make use of named constants.

sql/sql_acl.cc

@@ -184,6 +184,17 @@ static LEX_STRING old_password_plugin_name= {
 /// @todo make it configurable
 LEX_STRING *default_auth_plugin_name= &native_password_plugin_name;
 
+/*
+  Constant used for differentiating specified user names and non specified
+  usernames. Example: userA  -- userA@%
+*/
+const char *HOST_NOT_SPECIFIED= "%";
+/*
+  Constant used in the SET ROLE NONE command
+*/
+const char *NONE_ROLE= "NONE";
+
+
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
 static plugin_ref old_password_plugin;
 #endif

sql/sql_acl.h

@@ -173,6 +173,9 @@ enum mysql_db_table_field
 extern const TABLE_FIELD_DEF mysql_db_table_def;
 extern bool mysql_user_table_is_in_short_password_format;
 
+extern const char *HOST_NOT_SPECIFIED;
+extern const char *NONE_ROLE;
+
 
 static inline int access_denied_error_code(int passwd_used)
 {

sql/sql_yacc.yy

@@ -1570,7 +1570,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b, ulong *yystacksize);
 
 %type <symbol> keyword keyword_sp
 
-%type <lex_user> user specified_user grant_user role
+%type <lex_user> user grant_user
 
 %type <charset>
         opt_collate
@@ -1624,7 +1624,6 @@ bool my_yyoverflow(short **a, YYSTYPE **b, ulong *yystacksize);
         opt_option opt_place
         opt_attribute opt_attribute_list attribute column_list column_list_id
         opt_column_list grant_privileges grant_ident grant_list grant_option
-        grant_list_with_roles
         object_privilege object_privilege_list user_list rename_list
         clear_privileges flush_options flush_option
         opt_with_read_lock flush_options_list
@@ -13163,8 +13162,24 @@ ident_or_text:
         | LEX_HOSTNAME { $$=$1;}
         ;
 
-specified_user:
+user:
-          ident_or_text '@' ident_or_text
+          ident_or_text
+          {
+            if (!($$=(LEX_USER*) thd->alloc(sizeof(st_lex_user))))
+              MYSQL_YYABORT;
+            $$->user = $1;
+            $$->host.str= (char *)HOST_NOT_SPECIFIED;
+            $$->host.length= 1;
+            $$->password= null_lex_str; 
+            $$->plugin= empty_lex_str;
+            $$->auth= empty_lex_str;
+
+            if (check_string_char_length(&$$->user, ER(ER_USERNAME),
+                                         username_char_length,
+                                         system_charset_info, 0))
+              MYSQL_YYABORT;
+          }
+        | ident_or_text '@' ident_or_text
           {
             if (!($$=(LEX_USER*) thd->alloc(sizeof(st_lex_user))))
               MYSQL_YYABORT;
@@ -13198,46 +13213,6 @@ specified_user:
           }
         ;
 
-user:
-          ident_or_text
-          {
-            if (!($$=(LEX_USER*) thd->alloc(sizeof(st_lex_user))))
-              MYSQL_YYABORT;
-            $$->user = $1;
-            $$->host.str= (char *) "%";
-            $$->host.length= 1;
-            $$->password= null_lex_str; 
-            $$->plugin= empty_lex_str;
-            $$->auth= empty_lex_str;
-
-            if (check_string_char_length(&$$->user, ER(ER_USERNAME),
-                                         username_char_length,
-                                         system_charset_info, 0))
-              MYSQL_YYABORT;
-          }
-        |
-          specified_user {$$ = $1;}
-        ;
-
-role:
-          ident_or_text
-          {
-            if (!($$=(LEX_USER*) thd->alloc(sizeof(st_lex_user))))
-              MYSQL_YYABORT;
-            $$->user = $1;
-            $$->host.str= (char *) "";
-            $$->host.length= 0;
-            $$->password= null_lex_str;
-            $$->plugin= empty_lex_str;
-            $$->auth= empty_lex_str;
-
-            if (check_string_char_length(&$$->user, ER(ER_USERNAME),
-                                         username_char_length,
-                                         system_charset_info, 0))
-              MYSQL_YYABORT;
-          }
-        ;
-
 /* Keyword that we allow for identifiers (except SP labels) */
 keyword:
           keyword_sp            {}
@@ -14271,7 +14246,7 @@ revoke_command:
             lex->sql_command= SQLCOM_REVOKE;
             lex->type= TYPE_ENUM_PROXY;
           } 
-        | grant_role FROM grant_list_with_roles
+        | grant_role FROM grant_list
           {
             LEX *lex= Lex;
             lex->sql_command= SQLCOM_REVOKE_ROLE;
@@ -14325,7 +14300,7 @@ grant_command:
             lex->sql_command= SQLCOM_GRANT;
             lex->type= TYPE_ENUM_PROXY;
           }
-        | grant_role TO_SYM grant_list_with_roles
+        | grant_role TO_SYM grant_list
           {
             LEX *lex= Lex;
             lex->sql_command= SQLCOM_GRANT_ROLE;
@@ -14520,30 +14495,6 @@ user_list:
           }
         ;
 
-grant_list_with_roles:
-          role
-          {
-            if (Lex->users_list.push_back($1))
-              MYSQL_YYABORT;
-          }
-        | specified_user
-          {
-            if (Lex->users_list.push_back($1))
-              MYSQL_YYABORT;
-          }
-        | grant_list_with_roles ',' role
-          {
-            if (Lex->users_list.push_back($3))
-              MYSQL_YYABORT;
-          }
-        | grant_list_with_roles ',' specified_user
-          {
-            if (Lex->users_list.push_back($3))
-              MYSQL_YYABORT;
-          }
-        ;
-
-
 grant_list:
           grant_user
           {