CFSocket 的使用

1、CFSocket

  • 苹果对对底层 BSD Socket 进行轻量级的封装(纯 C)。

  • 主要使用的 API:CFSocekt 用于建立连接,CFStream 用于读写数据。

2、基本使用

2.1 Client 客户端

  • TCP 客户端

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    // 包含头文件
    #import <sys/socket.h>
    #import <netinet/in.h>
    #import <arpa/inet.h>

    @property (weak, nonatomic) IBOutlet UITextField *desIPTF;
    @property (weak, nonatomic) IBOutlet UITextField *desPortTF;

    @property (weak, nonatomic) IBOutlet UITextView *recvTextView;
    @property (weak, nonatomic) IBOutlet UITextField *sendTF;

    @property (nonatomic, assign) CFSocketRef clientSockfd;

    #pragma mark - 创建 TCP 连接

    - (IBAction)connectTCPServer:(id)sender {

    [NSThread detachNewThreadSelector:@selector(connectTCPSer) toTarget:self withObject:nil];
    }

    - (void)connectTCPSer {

    BOOL success;

    // 创建 socket
    self.clientSockfd = CFSocketCreate(kCFAllocatorDefault, PF_INET, SOCK_STREAM, IPPROTO_TCP, kCFSocketConnectCallBack, ServerConnectCallBack, NULL);
    success = (self.clientSockfd != NULL);

    NSString *logStr = nil;

    if (success == NO) {

    logStr = @"创建 socket 失败...\n";
    [self showMessage:logStr];

    return;

    } else {

    logStr = @"创建 socket 成功...\n";
    [self showMessage:logStr];

    // 服务器地址
    struct sockaddr_in ser_addr;
    memset(&ser_addr, 0, sizeof(ser_addr));
    ser_addr.sin_len = sizeof(ser_addr);
    ser_addr.sin_family = AF_INET;
    ser_addr.sin_port = htons(_desPortTF.text.intValue);
    ser_addr.sin_addr.s_addr = inet_addr(_desIPTF.text.UTF8String);

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

    // 连接
    CFSocketError result = CFSocketConnectToAddress(self.clientSockfd, address, 5);
    CFRelease(address);
    success = (result == kCFSocketSuccess);
    }

    if (success == NO) {

    logStr = @"socket 连接失败...\n";
    [self showMessage:logStr];

    return;

    } else {

    logStr = [NSString stringWithFormat:@"socket 连接 %@ 成功...\n", _desIPTF.text];
    [self showMessage:logStr];

    char buf[2048];
    do {
    // 接收数据
    ssize_t recvLen = recv(CFSocketGetNative(self.clientSockfd), buf, sizeof(buf), 0);

    if (recvLen > 0) {
    logStr = [NSString stringWithFormat:@"recv:%@\n", [NSString stringWithFormat:@"%s", buf]];
    [self showMessage:logStr];
    }

    } while (strcmp(buf, "exit") != 0);

    CFRunLoopRef cfrl = CFRunLoopGetCurrent();
    CFRunLoopSourceRef source = CFSocketCreateRunLoopSource(kCFAllocatorDefault, self.clientSockfd, 0);
    CFRunLoopAddSource(cfrl, source, kCFRunLoopCommonModes);
    CFRelease(source);
    CFRunLoopRun();
    }
    }

    // 连接成功的回调函数
    void ServerConnectCallBack(CFSocketRef socket, CFSocketCallBackType type, CFDataRef address, const void * data, void *info) {

    if (data != NULL) {
    NSLog(@"connect\n");
    } else {
    NSLog(@"connect success\n");
    }
    }

    #pragma mark - 发送数据

    - (IBAction)btnClick:(id)sender {

    if (_sendTF.text.length == 0) {
    return;
    } else {

    // 发送数据
    ssize_t sendLen = send(CFSocketGetNative(self.clientSockfd), _sendTF.text.UTF8String, strlen(_sendTF.text.UTF8String), 0);

    if (sendLen > 0) {
    NSString *logStr = [NSString stringWithFormat:@"send:%@\n", _sendTF.text];
    [self showMessage:logStr];
    }
    }
    }

    // 显示信息
    - (void)showMessage:(NSString *)msg {

    dispatch_async(dispatch_get_main_queue(), ^{

    _recvTextView.text = [_recvTextView.text stringByAppendingString:msg];
    });
    }

    // 键盘回收
    - (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    [self.view endEditing:YES];
    }

2.2 Server 服务端

  • TCP 服务端

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    // 包含头文件
    #import <sys/socket.h>
    #import <netinet/in.h>
    #import <arpa/inet.h>
    #import <ifaddrs.h>

    static ViewController *selfClass = nil;

    @property (weak, nonatomic) IBOutlet UITextField *locIPTF;
    @property (weak, nonatomic) IBOutlet UITextField *locPortTF;

    @property (weak, nonatomic) IBOutlet UITextView *recvTextView;
    @property (weak, nonatomic) IBOutlet UITextField *sendTF;

    @property (nonatomic, assign) CFSocketRef serverSockfd;

    @property (nonatomic, assign) CFWriteStreamRef outputStream;

    - (void)viewDidLoad {
    [super viewDidLoad];

    NSString *ip_addr = [self getIPAddress];
    _locIPTF.text = ip_addr;

    // 函数指针指向本身
    selfClass = self;
    }

    #pragma mark - 创建 TCP 监听

    - (IBAction)createdTCPServer:(id)sender {

    [sender setTitleColor:[UIColor redColor] forState:UIControlStateNormal];

    [NSThread detachNewThreadSelector:@selector(createdTCPSer) toTarget:self withObject:nil];
    }

    - (void)createdTCPSer {

    BOOL success;

    // 创建 socket
    self.serverSockfd = CFSocketCreate(kCFAllocatorDefault, PF_INET, SOCK_STREAM, IPPROTO_TCP, kCFSocketAcceptCallBack, TCPServerAcceptCallBack, NULL);
    success = (self.serverSockfd != NULL);

    NSString *logStr = nil;

    if (success == NO) {

    logStr = @"创建 socket 失败...\n";
    [self showMessage:logStr];

    return;

    } else {

    logStr = @"创建 socket 成功...\n";
    [self showMessage:logStr];

    int optVal = 1;
    setsockopt(CFSocketGetNative(self.serverSockfd), SOL_SOCKET, SO_REUSEADDR, (void*)&optVal,sizeof(optVal));

    // 本地地址
    struct sockaddr_in loc_addr;
    memset(&loc_addr, 0, sizeof(loc_addr));
    loc_addr.sin_family = AF_INET;
    loc_addr.sin_port = htons(_locPortTF.text.intValue);
    loc_addr.sin_addr.s_addr = inet_addr(_locIPTF.text.UTF8String);

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

    // 绑定
    CFSocketError err = CFSocketSetAddress(self.serverSockfd, address);
    CFRelease(address);
    success = (err == kCFSocketSuccess);
    }

    if (success == NO) {

    logStr = @"socket 绑定失败...\n";
    [self showMessage:logStr];

    CFRelease(self.serverSockfd);
    self.serverSockfd = NULL;

    return;

    } else {

    logStr = @"socket 绑定成功...\n";
    [self showMessage:logStr];

    CFRunLoopRef cfRunloop = CFRunLoopGetCurrent();
    CFRunLoopSourceRef source = CFSocketCreateRunLoopSource(kCFAllocatorDefault, self.serverSockfd, 0);
    CFRunLoopAddSource(cfRunloop, source, kCFRunLoopCommonModes);
    CFRelease(source);
    CFRunLoopRun();
    }
    }

    // 客户端连接成功的回调函数
    void TCPServerAcceptCallBack(CFSocketRef socket ,CFSocketCallBackType type,CFDataRef address,const void *data, void *info) {

    // 客户端连接
    if (kCFSocketAcceptCallBack == type) {

    // data the handle of socket
    CFSocketNativeHandle nativeSocketHandle = *(CFSocketNativeHandle *)data;

    uint8_t name[SOCK_MAXADDRLEN];
    socklen_t nameLen = sizeof(name);

    // 获取对方 socket 信息,还有 getsocketname() 函数用于获取本程序所在 socket 信息
    if (getpeername(nativeSocketHandle, (struct sockaddr *)name, &nameLen) != 0) {
    exit(1);
    }

    // 获取连接的客户端信息
    struct sockaddr_in * addr_in = (struct sockaddr_in *)name;
    char *ip_addr = inet_ntoa(addr_in->sin_addr);
    int ip_port = addr_in->sin_port;

    NSString *logStr = [NSString stringWithFormat:@"已连接:%s,port:%d\n", ip_addr, ip_port];
    [selfClass showMessage:logStr];

    // 创建一对输入输出流用于读写数据
    CFReadStreamRef iStream;
    CFWriteStreamRef oStream;

    // 创建一组可读/写的 CFStreame
    CFStreamCreatePairWithSocket(kCFAllocatorDefault, nativeSocketHandle, &iStream, &oStream);

    if (iStream && oStream) {

    // 打开输入流和输出流
    CFReadStreamOpen(iStream);
    CFWriteStreamOpen(oStream);

    CFStreamClientContext streamContext = {0, NULL, NULL, NULL};

    // if have data to read call the readStream function
    if (!CFReadStreamSetClient(iStream, kCFStreamEventHasBytesAvailable, readStream, &streamContext)) {
    exit(1);
    }

    CFReadStreamScheduleWithRunLoop(iStream, CFRunLoopGetCurrent(), kCFRunLoopCommonModes);

    selfClass.outputStream = oStream;
    }
    }
    }

    // 读取数据的回调函数
    void readStream(CFReadStreamRef iStream, CFStreamEventType eventType, void * clientCallBackInfo){

    char buf[2048];
    bzero(buf, sizeof(buf));

    do {
    // 接收数据
    CFIndex dex = CFReadStreamRead(iStream, (UInt8 *)buf, sizeof(buf));

    if (dex > 0) {
    NSString *logStr = [NSString stringWithFormat:@"recv:%@\n", [NSString stringWithFormat:@"%s", buf]];
    [selfClass showMessage:logStr];
    }

    } while (strcmp(buf, "exit") != 0);
    }

    #pragma mark - 发送数据

    - (IBAction)btnClick:(id)sender {

    if (_sendTF.text.length == 0) {
    return;
    } else {

    // 发送数据
    CFIndex dex = CFWriteStreamWrite(selfClass.outputStream, (UInt8 *)_sendTF.text.UTF8String, strlen(_sendTF.text.UTF8String)+1);

    if (dex > 0) {
    NSString *logStr = [NSString stringWithFormat:@"send:%@\n", _sendTF.text];
    [self showMessage:logStr];
    }
    }
    }

    #pragma mark - 获取本地 IP 地址

    - (NSString *)getIPAddress {

    NSString *address = @"error";
    struct ifaddrs *interfaces = NULL;
    struct ifaddrs *temp_addr = NULL;
    int success = 0;

    // retrieve the current interfaces - returns 0 on success
    success = getifaddrs(&interfaces);

    if (success == 0) {

    // Loop through linked list of interfaces
    temp_addr = interfaces;

    while (temp_addr != NULL) {

    if (temp_addr->ifa_addr->sa_family == AF_INET) {

    // Check if interface is en0 which is the wifi connection on the iPhone
    if ([[NSString stringWithUTF8String:temp_addr->ifa_name] isEqualToString:@"en0"]) {

    // Get NSString from C String
    address = [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr)];
    }
    }
    temp_addr = temp_addr->ifa_next;
    }
    }

    // Free memory
    freeifaddrs(interfaces);
    return address;
    }

    // 显示信息
    - (void)showMessage:(NSString *)msg {

    dispatch_async(dispatch_get_main_queue(), ^{

    _recvTextView.text = [_recvTextView.text stringByAppendingString:msg];
    });
    }

    // 键盘回收
    - (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
    [self.view endEditing:YES];
    }

文章目录
  1. 1. 1、CFSocket
  2. 2. 2、基本使用
    1. 2.1. 2.1 Client 客户端
    2. 2.2. 2.2 Server 服务端
隐藏目录