1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 // This file provides a class interface for cross-platform socket functionality. The main fastboot 30 // engine should not be using this interface directly, but instead should use a higher-level 31 // interface that enforces the fastboot protocol. 32 33 #pragma once 34 35 #include <functional> 36 #include <memory> 37 #include <string> 38 #include <utility> 39 #include <vector> 40 41 #include <android-base/macros.h> 42 #include <cutils/sockets.h> 43 #include <gtest/gtest_prod.h> 44 45 // Socket interface to be implemented for each platform. 46 class Socket { 47 public: 48 enum class Protocol { kTcp, kUdp }; 49 50 // Returns the socket error message. This must be called immediately after a socket failure 51 // before any other system calls are made. 52 static std::string GetErrorMessage(); 53 54 // Creates a new client connection. Clients are connected to a specific hostname/port and can 55 // only send to that destination. 56 // On failure, |error| is filled (if non-null) and nullptr is returned. 57 static std::unique_ptr<Socket> NewClient(Protocol protocol, const std::string& hostname, 58 int port, std::string* error); 59 60 // Creates a new server bound to local |port|. This is only meant for testing, during normal 61 // fastboot operation the device acts as the server. 62 // A UDP server saves sender addresses in Receive(), and uses the most recent address during 63 // calls to Send(). 64 static std::unique_ptr<Socket> NewServer(Protocol protocol, int port); 65 66 // Destructor closes the socket if it's open. 67 virtual ~Socket(); 68 69 // Sends |length| bytes of |data|. For TCP sockets this will continue trying to send until all 70 // bytes are transmitted. Returns true on success. 71 virtual bool Send(const void* data, size_t length) = 0; 72 73 // Sends |buffers| using multi-buffer write, which can be significantly faster than making 74 // multiple calls. For UDP sockets |buffers| are all combined into a single datagram; for 75 // TCP sockets this will continue sending until all buffers are fully transmitted. Returns true 76 // on success. 77 // 78 // Note: This is non-functional for UDP server Sockets because it's not currently needed and 79 // would require an additional sendto() variation of multi-buffer write. 80 virtual bool Send(std::vector<cutils_socket_buffer_t> buffers) = 0; 81 82 // Waits up to |timeout_ms| to receive up to |length| bytes of data. |timout_ms| of 0 will 83 // block forever. Returns the number of bytes received or -1 on error/timeout; see 84 // ReceiveTimedOut() to distinguish between the two. 85 virtual ssize_t Receive(void* data, size_t length, int timeout_ms) = 0; 86 87 // Calls Receive() until exactly |length| bytes have been received or an error occurs. 88 virtual ssize_t ReceiveAll(void* data, size_t length, int timeout_ms); 89 90 // Returns true if the last Receive() call timed out normally and can be retried; fatal errors 91 // or successful reads will return false. ReceiveTimedOut()92 bool ReceiveTimedOut() { return receive_timed_out_; } 93 94 // Closes the socket. Returns 0 on success, -1 on error. 95 virtual int Close(); 96 97 // Accepts an incoming TCP connection. No effect for UDP sockets. Returns a new Socket 98 // connected to the client on success, nullptr on failure. Accept()99 virtual std::unique_ptr<Socket> Accept() { return nullptr; } 100 101 // Returns the local port the Socket is bound to or -1 on error. 102 int GetLocalPort(); 103 104 protected: 105 // Protected constructor to force factory function use. 106 explicit Socket(cutils_socket_t sock); 107 108 // Blocks up to |timeout_ms| until a read is possible on |sock_|, and sets |receive_timed_out_| 109 // as appropriate to help distinguish between normal timeouts and fatal errors. Returns true if 110 // a subsequent recv() on |sock_| will complete without blocking or if |timeout_ms| <= 0. 111 bool WaitForRecv(int timeout_ms); 112 113 cutils_socket_t sock_ = INVALID_SOCKET; 114 bool receive_timed_out_ = false; 115 116 // Non-class functions we want to override during tests to verify functionality. Implementation 117 // should call this rather than using socket_send_buffers() directly. 118 std::function<ssize_t(cutils_socket_t, cutils_socket_buffer_t*, size_t)> 119 socket_send_buffers_function_ = &socket_send_buffers; 120 121 private: 122 FRIEND_TEST(SocketTest, TestTcpSendBuffers); 123 FRIEND_TEST(SocketTest, TestUdpSendBuffers); 124 125 DISALLOW_COPY_AND_ASSIGN(Socket); 126 }; 127