网络编程CFSocketRef

1、网络编程 CFSocketRefCFSocketCreateCreates a CFSocket object of a specified protocol and type. CFSocketRef CFSocketCreate (CFAllocatorRef allocator,SInt32 protocolFamily, SInt32 socketType, SInt32 protocol, CFOptionFlags callBackTypes, CFSocketCallBack callout, const CFSocketContext *context );- (void)se

2、tTextInMainThread:(NSString *)text NSRange endRange;endRange.location = chatController.textView.text length;endRange.length = textlength;chatController.textView.text= chatController.textView.text stringByAppendingString:server: stringByAppendingString:text;chatController.textView scrollRangeToVisibl

3、e:endRange;- (void)readStreamchar buffer255;NSAutoreleasePool * pool = NSAutoreleasePoolallocinit;while (recv(CFSocketGetNative(_socket),buffer, sizeof(buffer),0) NSString *s = NSString stringWithUTF8String:buffer;self performSelectorOnMainThread:selector(setTextInMainThread :)withObject:s waitUntil

4、Done:YES;pool release;staticvoid TCPServerConnectCallBack(CFSocketRef socket, CFSocketCallBackType type,CFDataRef address, const void *data, void *info) if (data !=NULL) UIAlertView *alert = UIAlertView alloc initWithTitle:message:连接失败”delegate:nil cancelButtonTitle: 关闭 otherButtonTitles:nil;alert s

5、how;alertrelease;return;TCPClientDemoAppDelegate *delegate = (TCPClientDemoAppDelegate *)info;delegate performSelectorInBackground:selector(readStream) withObject:nil;delegate.connController dismissModalViewControllerAnimated:YES;NSNotificationCenter defaultCenter addObserver:delegate.chatController

6、 selector:selector(keyboardWillShown:) name:UIKeyboardWillShowNotification object:nil;NSNotificationCenter defaultCenter addObserver:delegate.chatControllerselector:selector(keyboardWillHidden:) name:UIKeyboardWillHideNotification object:nil;- (void) doConnect / CFSocketContext 存放一些 CFSocketRef 的相关信

7、息CFSocketContext CTX = 0,self, NULL,NULL, NULL;/ CFSocketCreate 函数是用来创建一个CFSocketRef ，第一个参数是表示由系统默认的 allocator 来为 CFSocketRef 分配一个内存空间。/ 第二个参数表示profocolFamily (协议簇)/ 第三个参数表示 socketType（ socket 的类型流、数据段、 顺序包 .）/ 第四个参数表示protocol (协议 tcp、udp.)/ 第五个参数表示当 socket 的某个类型 activity 时，调用第 六个参数的函数/ 第六个参数表示当 soc

8、ket 发生第五个参数的类型的动作 时，调用的函数/ 第七个参数表示一个保存CFSocket object 对象的一些相关信息_socket = CFSocketCreate(kCFAllocatorDefault,PF_INET, SOCK_STREAM,IPPROTO_TCP, kCFSocketConnectCallBack, TCPServerConnectCallBack, &CTX);if (NULL =_socket) UIAlertView *alert = UIAlertView alloc initWithTitle:message:创建套接字失败”delegate

9、:nil cancelButtonTitle: 关闭 otherButtonTitles:nil;alert show;alertrelease;/ sockaddr_in 是一个 struct，里面包含 ip、端口等 struct sockaddr_in addr4;memset(&addr4,0, sizeof(addr4);/ memset 表示将地址 addr4 结构里面的前sizeof ()个内存地址里面的内容设置成intoaddr4.sin_len =sizeof(addr4);addr4.sin_family =AF_INET;addr4.sin_port =htons(

10、12345);addr4.sin_addr.s_addr = inet_addr(connController.textField.textUTF8String);/ CFDataCreate() 是用来将一个申请一个 sizeof() 大小的内存空间，并将一个 buffer 中的数据拷贝到新申请的 内存空间中CFDataRef address =CFDataCreate(kCFAllocatorDefault, (UInt8 *)&addr4, sizeof(addr4);CFSocketConnectToAddress(_socket, address,-1);CFRunLoopR

11、ef cfrl = CFRunLoopGetCurrent();CFRunLoopSourceRef source =CFSocketCreateRunLoopSource(kCFAllocatorDefault, _socket,0);CFRunLoopAddSource(cfrl, source,kCFRunLoopCommonModes);CFRelease(source);- (void) sendMessage NSString *stringToSend = chatController.textField.textstringByAppendingString:n;constch

12、ar *data = stringToSendUTF8String;send(CFSocketGetNative(_socket), data,strlen(data) + 1,0);NSRange endRange;endRange.location = chatController.textView.text length;endRange.length = stringToSendlength;chatController.textView.text= chatController.textView.text stringByAppendingString:me: stringByApp

13、endingString:stringToSend;chatController.textView scrollRangeToVisible:endRange;chatController.textField.text = ;recv(), recvfrom()Receive data on a socketPrototypes#include <sys/types.h> #include <sys/socket.h> ssize_t recv(int s, void *buf, size_t len, int flags); ssize_t recvfrom(int

14、s, void *buf, size_t len, int flags, struct sockaddr *from, socklen_t *fromlen);DescriptionOnce you have a socket up and connected, you can read incoming data from the remote side using the recv()(for TCP SOCK_STREAM sockets) and recvfrom() (for UDP SOCK_DGRAM sockets).Both functions take the socket

15、 descriptor s, a pointer to the buffer buf, the size (in bytes) of the buffer len, and a set of flags that control how the functions work.Additionally, the recvfrom() takes a struct sockaddr*, from that will tell you where the data came from, and will fill in fromlen with the size of struct sockaddr

16、. (You must also initialize fromlen tobe the size offrom or struct sockaddr.)So what wondrous flags can you pass into this function? Here are some of them, but you should check your local man pages for more information and what is actually supported on your system. You bitwise-or these together, or

17、just set flags to 0 if you want it to be a regular vanilla recv().MSG_OOBReceive Out of Band data. This is how to get data that has been sent to you with the MSG_OOB flag in send(). As the receiving side, you will have had signal SIGURG raised telling you there is urgent data. In your handler for th

18、at signal, you could call recv() with this MSG_OOB flag.MSG_PEEKIf you want to call recv() just for pretend, you can call it with this flag. This will tell you whats waiting in the buffer for when you call recv() for real (i.e. without the MSG_PEEK flag. Its like a sneak preview into the nextrecv() call.