IOS上的socket通信



 

客户端：
导入头文件：
#import <sys/socket.h>
#import <netinet/in.h>
#import <arpa/inet.h>
#import <unistd.h>
1. 创建连接

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CFSocketContext sockContext = {0,// 结构体的版本，必须为0

self,

 

 // 一个任意指针的数据，可以用在创建时CFSocket对象相关联。这个指针被传递给所有的上下文中定义的回调。

 NULL,// 一个定义在上面指针中的retain的回调， 可以为NULL

 NULL,NULL};

CFSocketRef _socket = (kCFAllocatorDefault,// 为新对象分配内存，可以为nil

 PF_INET,// 协议族，如果为0或者负数，则默认为PF_INET

 SOCK_STREAM,// 套接字类型，如果协议族为PF_INET,则它会默认为SOCK_STREAM

 IPPROTO_TCP,// 套接字协议，如果协议族是PF_INET且协议是0或者负数，它会默认为IPPROTO_TCP

 kCFSocketConnectCallBack,// 触发回调函数的socket消息类型，具体见Callback Types

 TCPServerConnectCallBack,// 上面情况下触发的回调函数

 &sockContext// 一个持有CFSocket结构信息的对象，可以为nil

 );

　　

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if (_socket != nil) {

    structsockaddr_in addr4;   // IPV4

    memset(&addr4, 0,sizeof(addr4));

    addr4.sin_len =sizeof(addr4);

    addr4.sin_family = AF_INET;

    addr4.sin_port = htons(8888);

    addr4.sin_addr.s_addr = inet_addr([strAddress UTF8String]); // 把字符串的地址转换为机器可识别的网络地址

        

    // 把sockaddr_in结构体中的地址转换为Data

    CFDataRef address = CFDataCreate(kCFAllocatorDefault, (UInt8 *)&addr4,sizeof(addr4));

    CFSocketConnectToAddress(_socket,// 连接的socket

 address,// CFDataRef类型的包含上面socket的远程地址的对象

 -1 // 连接超时时间，如果为负，则不尝试连接，而是把连接放在后台进行，如果_socket消息类型为kCFSocketConnectCallBack，将会在连接成功或失败的时候在后台触发回调函数

 );

    CFRunLoopRef cRunRef = CFRunLoopGetCurrent();   // 获取当前线程的循环

    // 创建一个循环，但并没有真正加如到循环中，需要调用CFRunLoopAddSource

    CFRunLoopSourceRef sourceRef = CFSocketCreateRunLoopSource(kCFAllocatorDefault, _socket, 0);

    CFRunLoopAddSource(cRunRef,// 运行循环

    sourceRef, // 增加的运行循环源, 它会被retain一次

    kCFRunLoopCommonModes // 增加的运行循环源的模式

    );

    CFRelease(courceRef);

}

　　

2. 设置回调函数

  1 // socket回调函数的格式：  2 static void TCPServerConnectCallBack(CFSocketRef socket, CFSocketCallBackType type, CFDataRef address, const void *data, void *info) ｛  3     if (data != NULL) {  4         // 当socket为kCFSocketConnectCallBack时，失败时回调失败会返回一个错误代码指针，其他情况返回NULL  5         NSLog(@"连接失败");  6         return;  7     }  8     TCPClient *client = (TCPClient *)info;  9     // 读取接收的数据 10     [info performSlectorInBackground:@selector(readStream) withObject:nil]; 11 ｝ 12 3. 接收发送数据 13 // 读取接收的数据 14 - (void)readStream { 15     char buffer[1024]; 16     NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; 17     while (recv(CFSocketGetNative(_socket), //与本机关联的Socket 如果已经失效返回－1:INVALID_SOCKET 18            buffer, sizeof(buffer), 0)) { 19         NSLog(@"%@", [NSString stringWithUTF8String:buffer]); 20     } 21 } 22 // 发送数据 23 - (void)sendMessage { 24     NSString *stringTosend = @"你好"; 25     char *data = [stringTosend UTF8String]; 26     send(SFSocketGetNative(_socket), data, strlen(data) + 1, 0); 27 } 28 服务器端： 29 CFSockteRef _socket; 30 CFWriteStreamRef outputStream = NULL; 31 int setupSocket() { 32     _socket = CFSocketCreate(kCFAllocatorDefault, PF_INET, SOCK_STREAM, IPPROTO_TCP, kCFSocketAcceptCallBack, TCPServerAcceptCallBack, NULL); 33     if (NULL == _socket) { 34         NSLog(@"Cannot create socket!"); 35         return 0; 36     } 37     38     int optval = 1; 39     setsockopt(CFSocketGetNative(_socket), SOL_SOCKET, SO_REUSEADDR, // 允许重用本地地址和端口 40 (void *)&optval, sizeof(optval)); 41     42     struct sockaddr_in addr4; 43     memset(&addr4, 0, sizeof(addr4)); 44     addr4.sin_len = sizeof(addr4); 45     addr4.sin_family = AF_INET; 46     addr4.sin_port = htons(port); 47     addr4.sin_addr.s_addr = htonl(INADDR_ANY); 48     CFDataRef address = CFDataCreate(kCFAllocatorDefault, (UInt8 *)&addr4, sizeof(addr4)); 49     50     if (kCFSocketSuccess != CFSocketSetAddress(_socket, address)) { 51         NSLog(@"Bind to address failed!"); 52         if (_socket) 53              CFRelease(_socket); 54         _socket = NULL; 55         return 0; 56     } 57         58     CFRunLoopRef cfRunLoop = CFRunLoopGetCurrent(); 59     CFRunLoopSourceRef source = CFSocketCreateRunLoopSource(kCFAllocatorDefault, _socket, 0); 60     CFRunLoopAddSource(cfRunLoop, source, kCFRunLoopCommonModes); 61     CFRelease(source); 62     63     return 1; 64 } 65 // socket回调函数，同客户端 66 void TCPServerAcceptCallBack(CFSocketRef socket, CFSocketCallBackType type, CFDataRef address, const void *data, void *info) { 67     if (kCFSocketAcceptCallBack == type) { 68         // 本地套接字句柄 69         CFSocketNativeHandle nativeSocketHandle = *(CFSocketNativeHandle *)data; 70         uint8_t name[SOCK_MAXADDRLEN];       71         socklen_t nameLen = sizeof(name); 72         if (0 != getpeername(nativeSocketHandle, (struct sockaddr *)name, &nameLen)) { 73             NSLog(@"error"); 74             exit(1); 75         } 76         NSLog(@"%@ connected.", inet_ntoa( ((struct sockaddr_in *)name)->sin_addr )): 77         CFReadStreamRef iStream; 78         CFWriteStreamRef oStream; 79         // 创建一个可读写的socket连接 80         CFStreamCreatePairWithSocket(kCFAllocatorDefault, nativeSocketHandle, &iStream, &oStream);  81         if (iStream && oStream) { 82             CFStreamClientContext streamContext = {0, NULL, NULL, NULL}; 83             if (!CFReadStreamSetClient(iStream, kCFStreamEventHasBytesAvaiable, 84                                        readStream, // 回调函数，当有可读的数据时调用 85                                        &streamContext)){ 86                 exit(1); 87             } 88             if (!CFReadStreamSetClient(iStream, kCFStreamEventCanAcceptBytes, writeStream, &streamContext)){ 89                 exit(1); 90             } 91             CFReadStreamScheduleWithRunLoop(iStream, CFRunLoopGetCurrent(), kCFRunLoopCommomModes); 92             CFWriteStreamScheduleWithRunLoop(wStream, CFRunLoopGetCurrent(), kCFRunLoopCommomModes); 93             CFReadStreamOpen(iStream); 94             CFWriteStreamOpen(wStream); 95         } else { 96              close(nativeSocketHandle);  97         } 98     } 99 }100 // 读取数据101 void readStream(CFReadStreamRef stream, CFStreamEventType eventType, void *clientCallBackInfo) {102     UInt8 buff[255];103     CFReadStreamRead(stream, buff, 255);104     printf("received: %s", buff);105 }106 void writeStream (CFWriteStreamRef stream, CFStreamEventType eventType, void *clientCallBackInfo) {107     outputStream = stream;108 }109 main {110     char *str = "nihao";111    112     if (outputStream != NULL) {113         CFWriteStreamWrite(outputStream, str, strlen(line) + 1);114     } else {115         NSLog(@"Cannot send data!");116     }117 }118 // 开辟一个线程线程函数中119 void runLoopInThread() {120     int res = setupSocket();121     if (!res) {122         exit(1);123     }124     CFRunLoopRun();    // 运行当前线程的CFRunLoop对象125 }