1 // Copyright 2015 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef MOJO_PUBLIC_CPP_BINDINGS_LIB_UNION_ACCESSOR_H_ 6 #define MOJO_PUBLIC_CPP_BINDINGS_LIB_UNION_ACCESSOR_H_ 7 8 namespace mojo { 9 namespace internal { 10 11 // When serializing and deserializing Unions, it is necessary to access 12 // the private fields and methods of the Union. This allows us to do that 13 // without leaking those same fields and methods in the Union interface. 14 // All Union wrappers are friends of this class allowing such access. 15 template <typename U> 16 class UnionAccessor { 17 public: UnionAccessor(U * u)18 explicit UnionAccessor(U* u) : u_(u) {} 19 data()20 typename U::Union_* data() { return &(u_->data_); } 21 tag()22 typename U::Tag* tag() { return &(u_->tag_); } 23 SwitchActive(typename U::Tag new_tag)24 void SwitchActive(typename U::Tag new_tag) { u_->SwitchActive(new_tag); } 25 26 private: 27 U* u_; 28 }; 29 30 } // namespace internal 31 } // namespace mojo 32 33 #endif // MOJO_PUBLIC_CPP_BINDINGS_LIB_UNION_ACCESSOR_H_ 34