客戶端：
導入頭文件：
#import <sys/socket.h>
#import <netinet/in.h>
#import <arpa/inet.h>
#import <unistd.h>
1. 創建連接
CFSocketContext sockContext = {0, // 結構體的版本，必須為0
self,
// 一個任意指針的數據，可以用在創建時CFSocket對象相關聯。這個指針被傳遞給所有的上下文中定義的回調。
NULL, // 一個定義在上面指針中的retain的回調， 可以為NULL
NULL, NULL};
CFSocketRef _socket = (kCFAllocatorDefault, // 為新對象分配內存，可以為nil
PF_INET, // 協議族，如果為0或者負數，則默認為PF_INET
SOCK_STREAM, // 套接字類型，如果協議族為PF_INET,則它會默認為SOCK_STREAM
IPPROTO_TCP, // 套接字協議，如果協議族是PF_INET且協議是0或者負數，它會默認為IPPROTO_TCP
kCFSocketConnectCallBack, // 觸發回調函數的socket消息類型，具體見Callback Types
TCPServerConnectCallBack, // 上面情況下觸發的回調函數
&sockContext // 一個持有CFSocket結構信息的對象，可以為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]); // 把字符串的地址轉換為機器可識別的網絡地址
// 把sockaddr_in結構體中的地址轉換為Data
CFDataRef address = CFDataCreate(kCFAllocatorDefault, (UInt8 *)&addr4, sizeof(addr4));
CFSocketConnectToAddress(_socket, // 連接的socket
address, // CFDataRef類型的包含上面socket的遠程地址的對象
-1 // 連接超時時間，如果為負，則不嘗試連接，而是把連接放在后台進行，如果_socket消息類型為kCFSocketConnectCallBack，將會在連接成功或失敗的時候在后台觸發回調函數
);
CFRunLoopRef cRunRef = CFRunLoopGetCurrent(); // 獲取當前線程的循環
// 創建一個循環，但並沒有真正加如到循環中，需要調用CFRunLoopAddSource
CFRunLoopSourceRef sourceRef = CFSocketCreateRunLoopSource(kCFAllocatorDefault, _socket, 0);
CFRunLoopAddSource(cRunRef, // 運行循環
sourceRef, // 增加的運行循環源, 它會被retain一次
kCFRunLoopCommonModes // 增加的運行循環源的模式
);
CFRelease(courceRef);
}
2. 設置回調函數
1 // socket回調函數的格式：
2 static void TCPServerConnectCallBack(CFSocketRef socket, CFSocketCallBackType type, CFDataRef address, const void *data, void *info) ｛
3 if (data != NULL) {
4 // 當socket為kCFSocketConnectCallBack時，失敗時回調失敗會返回一個錯誤代碼指針，其他情況返回NULL
5 NSLog(@"連接失敗");
6 return;
7 }
8 TCPClient *client = (TCPClient *)info;
9 // 讀取接收的數據
10 [info performSlectorInBackground:@selector(readStream) withObject:nil];
11 ｝
12 3. 接收發送數據
13 // 讀取接收的數據
14 - (void)readStream {
15 char buffer[1024];
16 NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
17 while (recv(CFSocketGetNative(_socket), //與本機關聯的Socket 如果已經失效返回－1:INVALID_SOCKET
18 buffer, sizeof(buffer), 0)) {
19 NSLog(@"%@", [NSString stringWithUTF8String:buffer]);
20 }
21 }
22 // 發送數據
23 - (void)sendMessage {
24 NSString *stringTosend = @"你好";
25 char *data = [stringTosend UTF8String];
26 send(SFSocketGetNative(_socket), data, strlen(data) + 1, 0);
27 }
28 服務器端：
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, // 允許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回調函數，同客戶端
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 // 創建一個可讀寫的socket連接
80 CFStreamCreatePairWithSocket(kCFAllocatorDefault, nativeSocketHandle, &iStream, &oStream);
81 if (iStream && oStream) {
82 CFStreamClientContext streamContext = {0, NULL, NULL, NULL};
83 if (!CFReadStreamSetClient(iStream, kCFStreamEventHasBytesAvaiable,
84 readStream, // 回調函數，當有可讀的數據時調用
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 // 讀取數據
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 // 開辟一個線程線程函數中
119 void runLoopInThread() {
120 int res = setupSocket();
121 if (!res) {
122 exit(1);
123 }
124 CFRunLoopRun(); // 運行當前線程的CFRunLoop對象
125 }