1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
// 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
|
