| // Copyright (C) 2021 The Android Open Source Project |
| // |
| // 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. |
| #pragma once |
| #ifdef _WIN32 |
| #include "msvc-posix.h" |
| #endif |
| |
| #include <sys/types.h> |
| |
| #include <cstdint> |
| #include <functional> |
| #include <memory> |
| |
| namespace android { |
| namespace net { |
| |
| class AsyncDataChannel; |
| |
| // Callback function that will be used to notify that new data |
| // can be read. |
| using ReadCallback = std::function<void(AsyncDataChannel*)>; |
| |
| // A connected asynchronous socket abstraction. |
| // |
| // This is really a simple data channel that can be used to read and write |
| // data. Async Sockets are usually non-blocking posix/win sockets, but could be |
| // other types of datachannels (gRPC, qemu pipe) |
| class AsyncDataChannel { |
| public: |
| virtual ~AsyncDataChannel() = default; |
| |
| // Receive data in the given buffer. Properly handling EINTR where |
| // applicable. |
| // |
| // Returns: |
| // - >0: The number of bytes read. |
| // - 0: The socket is closed, no further reads/write are possible |
| // - <0: An error occurred. Details can be found in errno: |
| // - EAGAIN: No data, try again later. |
| // |
| // Implementors should take care of translating EWOULDBLOCK into EAGAIN |
| // if needed. |
| virtual ssize_t Recv(uint8_t* buffer, uint64_t bufferSize) = 0; |
| |
| // Send data in the given buffer. Properly handling EINTR, EPIPE where |
| // applicable. |
| // |
| // Returns: |
| // - >0: The number of bytes written, this can be < bufferSize. |
| // - <0: An error occurred. Details can be found in errno: |
| // - EAGAIN: The write would block, try again later. |
| // - EBADF: The connection is closed. |
| // |
| // Implementors should take care of translating EWOULDBLOCK into EAGAIN |
| // if needed. |
| virtual ssize_t Send(const uint8_t* buffer, uint64_t bufferSize) = 0; |
| |
| // True if this socket is connected |
| virtual bool Connected() = 0; |
| |
| // Closes this socket. Upon return the following will hold: |
| // |
| // - No more ReadCallbacks will be invoked. |
| // - Send/Recv calls will return 0. |
| virtual void Close() = 0; |
| |
| // Registers the given callback to be invoked when a recv call can be made |
| // to read data from this socket. The expectation is that a call to Recv will |
| // not return EAGAIN. Returns false if registration of the watcher failed. |
| // |
| // Only one callback can be registered per socket. |
| virtual bool WatchForNonBlockingRead( |
| const ReadCallback& on_read_ready_callback) = 0; |
| |
| // Stops watching this socket, you will not receive any callbacks any longer. |
| virtual void StopWatching() = 0; |
| }; |
| |
| } // namespace net |
| } // namespace android |