在CFSocket中,TCP连接的创建为
csocket = CFSocketCreate(
kCFAllocatorDefault,
PF_INET,
SOCK_STREAM,
IPPROTO_TCP,
kCFSocketReadCallBack,
TCPServerConnectCallBack,
&ctx);
。。。。
sError = CFSocketConnectToAddress(csocket,address, -1);
这里在连接成功时回调用TCPServerConnectCallBack方法,
那么如果需要UDP传输数据的话,
csocket = CFSocketCreate(
kCFAllocatorDefault,
PF_INET,
SOCK_DGRAM,
IPPROTO_UDP,
kCFSocketConnectCallBack,
TCPServerConnectCallBack,
&ctx);
1.TCP是有连接的,可靠的、可控制的、无边界的socket通信。
2.UDP是无连接的、不可靠的 数据报通信。但是效率高。
所以在TCP中要用回调来确定是否连接成功,而原生的socket连接成功是通过serveice发回信息来确定。UDP无连接,所以不需要回调,而不管是否发送成功。
第三部分、完整的使用方法
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
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CallbackTypes
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
);
if (_socket != nil) {
struct sockaddr_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
// socket回调函数的格式:
static void TCPServerConnectCallBack(CFSocketRefsocket, CFSocketCallBackType type, CFDataRef address, const void *data, void*info) {
if (data != NULL) {
// 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
NSLog(@"连接失败");
return;
}
TCPClient *client = (TCPClient *)info;
// 读取接收的数据
[info performSlectorInBackground:@selector(readStream) withObject:nil];
}
3. 接收发送数据
// 读取接收的数据
- (void)readStream {
char buffer[1024];
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
while (recv(CFSocketGetNative(_socket), //与本机关联的Socket 如果已经失效返回-1:INVALID_SOCKET
buffer, sizeof(buffer), 0)) {
NSLog(@"%@", [NSString stringWithUTF8String:buffer]);
}
}
// 发送数据
- (void)sendMessage {
NSString*stringTosend = @"你好";
char *data = [stringTosend UTF8String];
send(SFSocketGetNative(_socket), data, strlen(data) + 1, 0);
}
服务器端:
CFSockteRef _socket;
CFWriteStreamRef outputStream = NULL;
int setupSocket() {
_socket = CFSocketCreate(kCFAllocatorDefault, PF_INET, SOCK_STREAM,IPPROTO_TCP, kCFSocketAcceptCallBack, TCPServerAcceptCallBack, NULL);
if (NULL == _socket) {
NSLog(@"Cannot create socket!");
return 0;
}
int optval = 1;
setsockopt(CFSocketGetNative(_socket), SOL_SOCKET, SO_REUSEADDR, // 允许重用本地地址和端口
(void *)&optval, sizeof(optval));
struct sockaddr_in addr4;
memset(&addr4, 0, sizeof(addr4));
addr4.sin_len = sizeof(addr4);
addr4.sin_family = AF_INET;
addr4.sin_port = htons(port);
addr4.sin_addr.s_addr = htonl(INADDR_ANY);
CFDataRef address = CFDataCreate(kCFAllocatorDefault, (UInt8*)&addr4, sizeof(addr4));
if (kCFSocketSuccess != CFSocketSetAddress(_socket, address)) {
NSLog(@"Bind to address failed!");
if (_socket)
CFRelease(_socket);
_socket = NULL;
return 0;
}
CFRunLoopRef cfRunLoop = CFRunLoopGetCurrent();
CFRunLoopSourceRef source = CFSocketCreateRunLoopSource(kCFAllocatorDefault,_socket, 0);
CFRunLoopAddSource(cfRunLoop, source, kCFRunLoopCommonModes);
CFRelease(source);
return 1;
}
// socket回调函数,同客户端
void TCPServerAcceptCallBack(CFSocketRefsocket, CFSocketCallBackType type, CFDataRef address, const void *data, void*info) {
if (kCFSocketAcceptCallBack == type) {
// 本地套接字句柄
CFSocketNativeHandle nativeSocketHandle = *(CFSocketNativeHandle *)data;
uint8_t name[SOCK_MAXADDRLEN];
socklen_t nameLen = sizeof(name);
if (0 != getpeername(nativeSocketHandle, (struct sockaddr *)name,&nameLen)) {
NSLog(@"error");
exit(1);
}
NSLog(@"%@ connected.", inet_ntoa( ((struct sockaddr_in*)name)->sin_addr )):
CFReadStreamRef iStream;
CFWriteStreamRef oStream;
// 创建一个可读写的socket连接
CFStreamCreatePairWithSocket(kCFAllocatorDefault,nativeSocketHandle, &iStream, &oStream);
if (iStream && oStream) {
CFStreamClientContext streamContext = {0, NULL, NULL, NULL};
if (!CFReadStreamSetClient(iStream, kCFStreamEventHasBytesAvaiable,
readStream, // 回调函数,当有可读的数据时调用
&streamContext)){
exit(1);
}
if (!CFReadStreamSetClient(iStream, kCFStreamEventCanAcceptBytes,writeStream, &streamContext)){
exit(1);
}
CFReadStreamScheduleWithRunLoop(iStream, CFRunLoopGetCurrent(),kCFRunLoopCommomModes);
CFWriteStreamScheduleWithRunLoop(wStream, CFRunLoopGetCurrent(),kCFRunLoopCommomModes);
CFReadStreamOpen(iStream);
CFWriteStreamOpen(wStream);
} else {
close(nativeSocketHandle);
}
}
}
// 读取数据
void readStream(CFReadStreamRef stream,CFStreamEventType eventType, void *clientCallBackInfo) {
UInt8 buff[255];
CFReadStreamRead(stream, buff, 255);
printf("received: %s", buff);
}
void writeStream (CFWriteStreamRef stream, CFStreamEventTypeeventType, void *clientCallBackInfo) {
outputStream = stream;
}
main {
char *str = "nihao";
if (outputStream != NULL) {
CFWriteStreamWrite(outputStream, str, strlen(line) + 1);
} else {
NSLog(@"Cannot send data!");
}
}
// 开辟一个线程线程函数中
void runLoopInThread() {
int res = setupSocket();
if (!res) {
exit(1);
}
CFRunLoopRun(); // 运行当前线程的CFRunLoop对象
}