占位图
文集
iOS开发之网络通信（1）—— 计算机网络
iOS开发之网络通信（2）—— HTTP(S)
iOS开发之网络通信（3）—— XML & JSON
iOS开发之网络通信（4）—— socket
iOS开发之网络通信（5）—— CocoaAsyncSocket
iOS开发之网络通信（6）—— AFNetworking & Alamofire
目录
一. Stream Socket
二. BSD Socket
- UDP
- TCP
socket是一种抽象层编程接口，用于应用程序间通过网络协议进行通信。其实现方式主要有两种：TCP和UDP。关于TCP和UDP，前文有介绍了：iOS开发之网络通信（1）—— 计算机网络。
iOS中，根据不同语言有不同的方法来创建socket连接：
- C：CFStream。
- OC：NSStream。
- Swift：Stream。
OC中的NSStream和Swift中的Stream类都是对CFStream的封装，而CFStream是基于TCP协议创建的socket连接，无法创建UDP socket连接。
iOS的另外一种原生创建socket方法 —— BSD Socket。伯克利套接字（Berkeley sockets，即BSD Socket）由伯克利大学研发，最终成为网络开发接口的标准。
socket调试工具：ssokit
一. Stream Socket
这种方式是基于TCP协议的socket连接。
client端代码（swift）：
protocol StreamSocketDelegate {
func eventCode(eventCode: Stream.Event)
func received(data: Data)
}
class StreamSocket: NSObject, StreamDelegate {
static let shared = StreamSocket() // 单例
var delegate: StreamSocketDelegate?
var iSream: InputStream?
var oStream: OutputStream?
// 创建socket连接
func create(host: String, port: UInt32) {
print(#function)
var readStream: Unmanaged<CFReadStream>?
var writeStream: Unmanaged<CFWriteStream>?
// 创建socket连接
CFStreamCreatePairWithSocketToHost(kCFAllocatorDefault, host as CFString, port, &readStream, &writeStream)
// 转换成 InputStream & OutputStream 对象
self.iSream = readStream?.takeRetainedValue()
self.oStream = writeStream?.takeRetainedValue()
if self.iSream == nil {
print("Erro read")
return
}
if self.oStream == nil {
print("Erro write")
return
}
self.iSream!.delegate = self
self.oStream!.delegate = self
self.iSream!.schedule(in: RunLoop.main, forMode: RunLoop.Mode.default)
self.oStream!.schedule(in: RunLoop.main, forMode: RunLoop.Mode.default)
self.iSream!.open()
self.oStream!.open()
}
// 关闭socket连接
func close() {
self.iSream?.close()
self.oStream?.close()
}
// 发送数据
func send(data: Data) {
guard self.oStream != nil,
self.oStream?.hasSpaceAvailable == true
else {
print("no space available")
return
}
let bytes = [UInt8](data)
self.oStream?.write(bytes, maxLength: data.count)
}
//MARK: - StreamDelegate
func stream(_ aStream: Stream, handle eventCode: Stream.Event) {
self.delegate?.eventCode(eventCode: eventCode)
switch eventCode {
case .openCompleted: // 打开完毕
print(#function, "openCompleted")
break
case .hasBytesAvailable: // 可读
print(#function, "hasBytesAvailable")
let buffer = UnsafeMutablePointer<UInt8>.allocate(capacity: 4096)
while (aStream as! InputStream).hasBytesAvailable {
let numberOfBytesRead = (aStream as! InputStream).read(buffer, maxLength: 4096)
if numberOfBytesRead < 0 { break }
let data = Data(bytes: buffer, count: numberOfBytesRead)
self.delegate?.received(data: data)
}
break
case .hasSpaceAvailable: // 可写
print(#function, "hasSpaceAvailable")
break
case .errorOccurred: // 发生错误
print(#function, "errorOccurred", "error: \(String(describing: aStream.streamError))")
break
case .endEncountered: // 结束
print(#function, "endEncountered")
break
default:
break
}
}
}
二. BSD Socket
1. UDP
UDP是无连接的，人们习惯将监听方称为服务端，将发送端作为客户端。
- 监听方需要进行IP地址绑定操作，可选择绑定本机IP（通常是192.168.1.x）或者是任意地址IP（0.0.0.0）进行监听。
- 发送方可以选择向指定IP地址发送，或者进行广播（255.255.255.255），广播需先开启广播服务。
#import "UDPSocket.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
static UDPSocket *_singleInstance = nil;
@implementation UDPSocket
#pragma mark - 单例
+ (instancetype)sharedInstance
{
return [[self alloc] init];
}
+ (instancetype)allocWithZone:(struct _NSZone *)zone
{
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
_singleInstance = [super allocWithZone:zone];
});
return _singleInstance;
}
- (instancetype)init
{
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
_singleInstance = [super init];
if (_singleInstance) {
// 在这里初始化self的属性和方法
}
});
return _singleInstance;
}
#pragma mark - 对象方法
- (void)send:(NSData *)data host:(NSString *)host port:(UInt16)port {
struct sockaddr_in addr;
bzero(&addr, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
addr.sin_addr.s_addr = inet_addr(host.UTF8String); // 如需广播，使用htonl(INADDR_BROADCAST);，等价inet_addr(“255.255.255.255”);。只能在局域网广播，路由器不做转发。
int socketFD = socket(AF_INET, SOCK_DGRAM, 0); // SOCK_STREAM为TCP，SOCK_DGRAM为UDP，SOCK_RAW为IP
if (socketFD < 0) {
perror("socket error \n");
return;
}
// 开启广播服务
const int broadcast = 1;
int status = setsockopt(socketFD, SOL_SOCKET, SO_BROADCAST, &broadcast, sizeof(broadcast));
if (status < 0)
{
printf("Error enabling address reuse (setsockopt)");
if ([self.delegate respondsToSelector:@selector(showMessage:)]) {
[self.delegate showMessage:@"Error enabling address reuse (setsockopt)"];
}
close(socketFD);
return;
}
ssize_t ret = sendto(socketFD, data.bytes, data.length, 0, (sockaddr *)&addr, sizeof(addr));
if (ret < 0)
{
printf("error in sendto() function. ret=%ld \n", ret);
if ([self.delegate respondsToSelector:@selector(showMessage:)]) {
[self.delegate showMessage:@"error in sendto() function."];
}
close(socketFD);
return;
}
printf("send: %s \n", data.bytes);
if ([self.delegate respondsToSelector:@selector(showMessage:)]) {
[self.delegate showMessage:[NSString stringWithFormat:@"send: %s", data.bytes]];
}
}
- (void)listen:(int)port {
int socketFD = socket(AF_INET, SOCK_DGRAM, 0); // SOCK_STREAM为TCP，SOCK_DGRAM为UDP，SOCK_RAW为IP
if (socketFD < 0) {
perror("socket error \n");
if ([self.delegate respondsToSelector:@selector(showMessage:)]) {
[self.delegate showMessage:@"socket error \n"];
}
return;
}
struct sockaddr_in addr;
bzero(&addr, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
addr.sin_addr.s_addr = htonl(INADDR_ANY); // 等价inet_addr("0.0.0.0");
int status = bind(socketFD, (sockaddr *)&addr, sizeof(addr));
if (status < 0)
{
printf("error in bind() function \n");
if ([self.delegate respondsToSelector:@selector(showMessage:)]) {
[self.delegate showMessage:@"error in bind() function \n"];
}
close(socketFD);
return;
}
char recv_msg[1024];
while (1) {
bzero(recv_msg, 1024);
long byte_num = recv(socketFD, recv_msg, 1024, 0);
recv_msg[byte_num] = '\0';
printf("receive: %s\n", recv_msg);
if ([self.delegate respondsToSelector:@selector(showMessage:)]) {
[self.delegate showMessage:[NSString stringWithFormat:@"receive: %s", recv_msg]];
}
}
}
@end
2. TCP
2.1 TCP Server
TCPServer.h
#import <Foundation/Foundation.h>
NS_ASSUME_NONNULL_BEGIN
typedef NS_ENUM(NSInteger, TCPServerEvent) {
TCPServerEvent_Error,
TCPServerEvent_Listen,
TCPServerEvent_Accept,
TCPServerEvent_Send,
TCPServerEvent_Receive
};
@protocol TCPServerDelegate <NSObject>
@optional
- (void)TCPServerEvent:(TCPServerEvent)event message:(NSString *)message;
@end
@interface TCPServer : NSObject
@property (nonatomic, weak) id<TCPServerDelegate> delegate;
@property (nonatomic, assign) int server_socket;
@property (nonatomic, assign) int client_socket;
@property (nonatomic, assign) BOOL bStop;
+ (instancetype)sharedInstance;
- (void)listenWithHost:(NSString *)host port:(int)port;
- (void)stop;
- (void)send:(NSData *)data;
@end
NS_ASSUME_NONNULL_END
TCPServer.m
#import "TCPServer.h"
#include <stdio.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <string.h>
static TCPServer *_singleInstance = nil;
@implementation TCPServer
#pragma mark - 单例
+ (instancetype)sharedInstance
{
return [[self alloc] init];
}
+ (instancetype)allocWithZone:(struct _NSZone *)zone
{
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
_singleInstance = [super allocWithZone:zone];
});
return _singleInstance;
}
- (instancetype)init
{
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
_singleInstance = [super init];
if (_singleInstance) {
// 在这里初始化self的属性和方法
}
});
return _singleInstance;
}
#pragma mark - 对象方法
- (void)listenWithHost:(NSString *)host port:(int)port {
struct sockaddr_in server_addr;
bzero(&server_addr, sizeof(server_addr));
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(port);
server_addr.sin_addr.s_addr = inet_addr(host.UTF8String);
self.server_socket = socket(AF_INET, SOCK_STREAM, 0); // SOCK_STREAM为TCP，SOCK_DGRAM为UDP，SOCK_RAW为IP
if (self.server_socket < 0) {
perror("socket error \n");
if ([self.delegate respondsToSelector:@selector(TCPServerEvent:message:)]) {
[self.delegate TCPServerEvent:TCPServerEvent_Error message:@"socket success"];
}
return;
}
// 绑定socket
int res = bind(self.server_socket, (struct sockaddr *)&server_addr, sizeof(server_addr));
if (res < 0) {
perror("bind error");
if ([self.delegate respondsToSelector:@selector(TCPServerEvent:message:)]) {
[self.delegate TCPServerEvent:TCPServerEvent_Error message:@"bind error"];
}
return;
}
// 监听
if (listen(self.server_socket, 5) == -1) {
perror("listen error");
if ([self.delegate respondsToSelector:@selector(TCPServerEvent:message:)]) {
[self.delegate TCPServerEvent:TCPServerEvent_Error message:@"listen error"];
}
return;
}
if ([self.delegate respondsToSelector:@selector(TCPServerEvent:message:)]) {
[self.delegate TCPServerEvent:TCPServerEvent_Listen message:@"listen success"];
}
// 接收客户端地址
struct sockaddr_in client_addr;
socklen_t addr_len;
self.client_socket = accept(self.server_socket, (struct sockaddr *)&client_addr, &addr_len);
if (self.client_socket == -1) {
perror("accept error");
if ([self.delegate respondsToSelector:@selector(TCPServerEvent:message:)]) {
[self.delegate TCPServerEvent:TCPServerEvent_Error message:@"accept error"];
}
return;
}
if ([self.delegate respondsToSelector:@selector(TCPServerEvent:message:)]) {
[self.delegate TCPServerEvent:TCPServerEvent_Accept message:@"accept success"];
}
char recv_msg[1024];
self.bStop = NO;
// 循环读取数据
while (1) {
if (self.bStop) break;
bzero(recv_msg, 1024);
long byte_num = recv(self.client_socket, recv_msg, 1024, 0);
if (byte_num > 0) {
recv_msg[byte_num] = '\0';
printf("receive: %s\n", recv_msg);
if ([self.delegate respondsToSelector:@selector(TCPServerEvent:message:)]) {
[self.delegate TCPServerEvent:TCPServerEvent_Receive message:[NSString stringWithFormat:@"receive: %s", recv_msg]];
}
}
}
}
- (void)stop {
self.bStop = YES;
close(self.server_socket);
close(self.client_socket);
}
- (void)send:(NSData *)data {
ssize_t ret = send(self.client_socket, (char *)data.bytes, data.length, 0);
if (ret < 0) {
perror("send error \n");
if ([self.delegate respondsToSelector:@selector(TCPServerEvent:message:)]) {
[self.delegate TCPServerEvent:TCPServerEvent_Error message:@"send error"];
}
}else {
printf("send data: %s\n", (char *)data.bytes);
if ([self.delegate respondsToSelector:@selector(TCPServerEvent:message:)]) {
[self.delegate TCPServerEvent:TCPServerEvent_Send message:[NSString stringWithFormat:@"send: %s", (char *)data.bytes]];
}
}
}
@end
2.2 TCP Client
TCPClient.h
#import <Foundation/Foundation.h>
NS_ASSUME_NONNULL_BEGIN
typedef NS_ENUM(NSInteger, TCPClientEvent) {
TCPClientEvent_Connected,
TCPClientEvent_ConnectFailed,
TCPClientEvent_SendSuccess,
TCPClientEvent_SendError,
TCPClientEvent_ReceiveData,
};
@protocol TCPClientDelegate <NSObject>
@optional
- (void)TCPClientEvent:(TCPClientEvent)event message:(NSString *)message;
@end
@interface TCPClient : NSObject
@property (nonatomic, weak) id<TCPClientDelegate> delegate;
@property (nonatomic, assign) int socketFD;
@property (nonatomic, assign) BOOL bStop;
+ (instancetype)sharedInstance;
- (void)connectWithHost:(NSString *)host port:(int)port;
- (void)disconnect;
- (void)send:(NSData *)data;
@end
NS_ASSUME_NONNULL_END
TCPClient.m
#import "TCPClient.h"
#include <stdio.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <string.h>
static TCPClient *_singleInstance = nil;
@implementation TCPClient
#pragma mark - 单例
+ (instancetype)sharedInstance
{
return [[self alloc] init];
}
+ (instancetype)allocWithZone:(struct _NSZone *)zone
{
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
_singleInstance = [super allocWithZone:zone];
});
return _singleInstance;
}
- (instancetype)init
{
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
_singleInstance = [super init];
if (_singleInstance) {
// 在这里初始化self的属性和方法
}
});
return _singleInstance;
}
#pragma mark - 对象方法
- (void)connectWithHost:(NSString *)host port:(int)port {
struct sockaddr_in server_addr;
bzero(&server_addr, sizeof(server_addr));
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(port);
server_addr.sin_addr.s_addr = inet_addr(host.UTF8String);
self.socketFD = socket(AF_INET, SOCK_STREAM, 0); // SOCK_STREAM为TCP，SOCK_DGRAM为UDP，SOCK_RAW为IP
if (self.socketFD < 0) {
perror("socket error \n");
return;
}
int ret = connect(self.socketFD, (struct sockaddr *)&server_addr, sizeof(struct sockaddr_in));
if (ret < 0) {
perror("connect error \n");
if ([self.delegate respondsToSelector:@selector(TCPClientEvent:message:)]) {
[self.delegate TCPClientEvent:TCPClientEvent_ConnectFailed message:@"connect error"];
}
return;
}
printf("connect success \n");
if ([self.delegate respondsToSelector:@selector(TCPClientEvent:message:)]) {
[self.delegate TCPClientEvent:TCPClientEvent_Connected message:@"connect success"];
}
char buffer[1024];
self.bStop = NO;
while (1) {
if (self.bStop) break;
bzero(buffer, 1024);
ssize_t byte_num = recv(self.socketFD, buffer, 1024, 0); // 阻塞直到收到数据
if (byte_num > 0) {
buffer[byte_num] = '\0';
printf("receive: %s\n", buffer);
if ([self.delegate respondsToSelector:@selector(TCPClientEvent:message:)]) {
[self.delegate TCPClientEvent:TCPClientEvent_ReceiveData message:[NSString stringWithFormat:@"receive: %s", buffer]];
}
}
}
}
- (void)disconnect {
self.bStop = YES;
close(self.socketFD);
}
- (void)send:(NSData *)data {
ssize_t ret = send(self.socketFD, (char *)data.bytes, data.length, 0);
if (ret < 0) {
perror("send error \n");
if ([self.delegate respondsToSelector:@selector(TCPClientEvent:message:)]) {
[self.delegate TCPClientEvent:TCPClientEvent_SendError message:@"send error"];
}
}else {
printf("send data: %s\n", (char *)data.bytes);
if ([self.delegate respondsToSelector:@selector(TCPClientEvent:message:)]) {
[self.delegate TCPClientEvent:TCPClientEvent_SendSuccess message:[NSString stringWithFormat:@"send: %s", (char *)data.bytes]];
}
}
}
@end
Demo: KKSocketDemo
