| // Copyright 2020 The Dawn Authors |
| // |
| // Licensed 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. |
| |
| #ifndef SRC_DAWN_WIRE_CHUNKEDCOMMANDHANDLER_H_ |
| #define SRC_DAWN_WIRE_CHUNKEDCOMMANDHANDLER_H_ |
| |
| #include <cstdint> |
| #include <limits> |
| #include <memory> |
| |
| #include "dawn/common/Assert.h" |
| #include "dawn/wire/Wire.h" |
| #include "dawn/wire/WireCmd_autogen.h" |
| |
| namespace dawn::wire { |
| |
| class ChunkedCommandHandler : public CommandHandler { |
| public: |
| ChunkedCommandHandler(); |
| ~ChunkedCommandHandler() override; |
| |
| const volatile char* HandleCommands(const volatile char* commands, size_t size) override; |
| |
| protected: |
| enum class ChunkedCommandsResult { |
| Passthrough, |
| Consumed, |
| Error, |
| }; |
| |
| // Returns |true| if the commands were entirely consumed into the chunked command vector |
| // and should be handled later once we receive all the command data. |
| // Returns |false| if commands should be handled now immediately. |
| ChunkedCommandsResult HandleChunkedCommands(const volatile char* commands, size_t size) { |
| uint64_t commandSize64 = reinterpret_cast<const volatile CmdHeader*>(commands)->commandSize; |
| |
| if (commandSize64 > std::numeric_limits<size_t>::max()) { |
| return ChunkedCommandsResult::Error; |
| } |
| size_t commandSize = static_cast<size_t>(commandSize64); |
| if (size < commandSize) { |
| return BeginChunkedCommandData(commands, commandSize, size); |
| } |
| return ChunkedCommandsResult::Passthrough; |
| } |
| |
| private: |
| virtual const volatile char* HandleCommandsImpl(const volatile char* commands, size_t size) = 0; |
| |
| ChunkedCommandsResult BeginChunkedCommandData(const volatile char* commands, |
| size_t commandSize, |
| size_t initialSize); |
| |
| size_t mChunkedCommandRemainingSize = 0; |
| size_t mChunkedCommandPutOffset = 0; |
| std::unique_ptr<char[]> mChunkedCommandData; |
| }; |
| |
| } // namespace dawn::wire |
| |
| #endif // SRC_DAWN_WIRE_CHUNKEDCOMMANDHANDLER_H_ |