cql3: Add role_name and parser rules

The `userOrRoleName` parser rule is important for future CQL
role-related statements.

`cql3::role_name` is a small utility for role-related CQL statements
that enforce an important property of role names: that they are always
lower-case unless quoted appropriately.

configure.py

@@ -406,6 +406,7 @@ scylla_core = (['database.cc',
                  'cql3/update_parameters.cc',
                  'cql3/ut_name.cc',
                  'cql3/user_options.cc',
+                 'cql3/role_name.cc',
                  'thrift/handler.cc',
                  'thrift/server.cc',
                  'thrift/thrift_validation.cc',

cql3/Cql.g

@@ -80,6 +80,7 @@ options {
 #include "cql3/maps.hh"
 #include "cql3/sets.hh"
 #include "cql3/lists.hh"
+#include "cql3/role_name.hh"
 #include "cql3/type_cast.hh"
 #include "cql3/tuples.hh"
 #include "cql3/user_types.hh"
@@ -1115,12 +1116,12 @@ userTypeName returns [uninitialized<cql3::ut_name> name]
     : (ks=ident '.')? ut=non_type_ident { $name = cql3::ut_name(ks, ut); }
     ;
 
-#if 0
-userOrRoleName returns [RoleName name]
-    @init { $name = new RoleName(); }
-    : roleName[name] {return $name;}
+userOrRoleName returns [uninitialized<cql3::role_name> name]
+    : t=IDENT              { $name = cql3::role_name($t.text, cql3::preserve_role_case::no); }
+    | t=QUOTED_NAME        { $name = cql3::role_name($t.text, cql3::preserve_role_case::yes); }
+    | k=unreserved_keyword { $name = cql3::role_name(k, cql3::preserve_role_case::no); }
+    | QMARK {add_recognition_error("Bind variables cannot be used for role names");}
     ;
-#endif
 
 ksName[::shared_ptr<cql3::keyspace_element_name> name]
     : t=IDENT              { $name->set_keyspace($t.text, false);}
@@ -1143,15 +1144,6 @@ idxName[::shared_ptr<cql3::index_name> name]
     | QMARK {add_recognition_error("Bind variables cannot be used for index names");}
     ;
 
-#if 0
-roleName[RoleName name]
-    : t=IDENT              { $name.setName($t.text, false); }
-    | t=QUOTED_NAME        { $name.setName($t.text, true); }
-    | k=unreserved_keyword { $name.setName(k, false); }
-    | QMARK {addRecognitionError("Bind variables cannot be used for role names");}
-    ;
-#endif
-
 constant returns [shared_ptr<cql3::constants::literal> constant]
     @init{std::string sign;}
     : t=STRING_LITERAL { $constant = cql3::constants::literal::string(sstring{$t.text}); }

cql3/role_name.cc

@@ -0,0 +1,59 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Copyright (C) 2017 ScyllaDB
+ *
+ * Modified by ScyllaDB
+ */
+
+/*
+ * This file is part of Scylla.
+ *
+ * Scylla is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Scylla is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Scylla.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "cql3/role_name.hh"
+
+#include <algorithm>
+
+namespace cql3 {
+
+role_name::role_name(sstring name, preserve_role_case p) : _name(std::move(name)) {
+    if (p == preserve_role_case::no) {
+        std::transform(_name.begin(), _name.end(), _name.begin(), &::tolower);
+    }
+}
+
+std::ostream& operator<<(std::ostream& os, const role_name& r) {
+    os << r.to_string();
+    return os;
+}
+
+}

cql3/role_name.hh

@@ -0,0 +1,69 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Copyright (C) 2017 ScyllaDB
+ *
+ * Modified by ScyllaDB
+ */
+
+/*
+ * This file is part of Scylla.
+ *
+ * Scylla is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Scylla is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Scylla.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <experimental/string_view>
+#include <iosfwd>
+
+#include <seastar/core/sstring.hh>
+
+#include "seastarx.hh"
+#include "stdx.hh"
+
+namespace cql3 {
+
+enum class preserve_role_case { yes, no };
+
+class role_name final {
+    sstring _name;
+
+public:
+    role_name(sstring name, preserve_role_case);
+
+    stdx::string_view to_string() const noexcept {
+        return _name;
+    }
+};
+
+std::ostream& operator<<(std::ostream&, const role_name&);
+
+}