1 // Copyright 2014 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_SHARED_PTR_H_ 6 #define MOJO_PUBLIC_CPP_BINDINGS_LIB_SHARED_PTR_H_ 7 8 #include "mojo/public/cpp/bindings/lib/shared_data.h" 9 10 namespace mojo { 11 namespace internal { 12 13 // Used to manage a heap-allocated instance of P that can be shared via 14 // reference counting. When the last reference is dropped, the instance is 15 // deleted. 16 template <typename P> 17 class SharedPtr { 18 public: SharedPtr()19 SharedPtr() {} 20 SharedPtr(P * ptr)21 explicit SharedPtr(P* ptr) { 22 impl_.mutable_value()->ptr = ptr; 23 } 24 25 // Default copy-constructor and assignment operator are OK. 26 get()27 P* get() { 28 return impl_.value().ptr; 29 } get()30 const P* get() const { 31 return impl_.value().ptr; 32 } 33 34 P* operator->() { return get(); } 35 const P* operator->() const { return get(); } 36 37 private: 38 class Impl { 39 public: ~Impl()40 ~Impl() { 41 if (ptr) 42 delete ptr; 43 } 44 Impl()45 Impl() : ptr(NULL) { 46 } 47 Impl(P * ptr)48 Impl(P* ptr) : ptr(ptr) { 49 } 50 51 P* ptr; 52 53 private: 54 MOJO_DISALLOW_COPY_AND_ASSIGN(Impl); 55 }; 56 57 SharedData<Impl> impl_; 58 }; 59 60 } // namespace mojo 61 } // namespace internal 62 63 #endif // MOJO_PUBLIC_CPP_BINDINGS_LIB_SHARED_PTR_H_ 64