1 /* 2 * Copyright (C) 2024 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef CHRE_UTIL_SYSTEM_MESSAGE_ROUTER_CALLBACK_ALLOCATOR_H_ 18 #define CHRE_UTIL_SYSTEM_MESSAGE_ROUTER_CALLBACK_ALLOCATOR_H_ 19 20 #include <pw_allocator/allocator.h> 21 #include <pw_allocator/capability.h> 22 #include <pw_allocator/unique_ptr.h> 23 #include <pw_containers/vector.h> 24 #include <pw_function/function.h> 25 #include <cstddef> 26 #include <optional> 27 28 #include "chre/platform/mutex.h" 29 30 namespace chre::message { 31 32 //! An allocator for message free callbacks 33 //! This allocator is used to store message free callbacks in a vector 34 //! The allocator will call the free callback when the message is deallocated 35 //! This is used to create pw::UniquePtrs for messages that have a free 36 //! callback. 37 //! @param Metadata The metadata type for the callback function 38 template <typename Metadata> 39 class MessageRouterCallbackAllocator : public pw::Allocator { 40 public: 41 static constexpr Capabilities kCapabilities = 0; 42 43 //! The callback used to free a message 44 using MessageFreeCallback = pw::Function<void( 45 std::byte *message, size_t length, const Metadata &metadata)>; 46 47 //! A record of a message and its free callback 48 struct FreeCallbackRecord { 49 std::byte *message; 50 Metadata metadata; 51 size_t messageSize; 52 }; 53 54 MessageRouterCallbackAllocator( 55 MessageFreeCallback &&callback, 56 pw::Vector<FreeCallbackRecord> &freeCallbackRecords); 57 58 //! @see pw::Allocator::DoAllocate 59 virtual void *DoAllocate(Layout /* layout */) override; 60 61 //! @see pw::Allocator::DoDeallocate 62 virtual void DoDeallocate(void *ptr) override; 63 64 //! Creates a pw::UniquePtr for a message with a free callback. 65 //! The free callback will be called when the message is deallocated. 66 //! @return A pw::UniquePtr containing the message 67 [[nodiscard]] pw::UniquePtr<std::byte[]> MakeUniqueArrayWithCallback( 68 std::byte *ptr, size_t size, Metadata &&metadata); 69 70 private: 71 //! The callback used to free a message 72 MessageFreeCallback mCallback; 73 74 //! The mutex to protect mFreeCallbackRecords 75 Mutex mMutex; 76 77 //! The map of message pointers to free callbacks 78 pw::Vector<FreeCallbackRecord> &mFreeCallbackRecords; 79 }; 80 81 } // namespace chre::message 82 83 #include "chre/util/system/message_router_callback_allocator_impl.h" 84 85 #endif // CHRE_UTIL_SYSTEM_MESSAGE_ROUTER_CALLBACK_ALLOCATOR_H_ 86