为了让服务器同时接受多个客户端访问，所以需要多进程或者多线程
多进程版本：
#include<unistd.h>
#include<stdio.h>
#include<stdlib.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<string.h>
static void usage(const char* proc)
{
printf("%s [ip] [port]", proc);
}
int startup(const char* _ip, int _port)
{
int sock = socket(AF_INET, SOCK_STREAM, 0);
if(sock < 0)
{
perror("socket");
return 2;
}
struct sockaddr_in local;
local.sin_family = AF_INET;
local.sin_port = htons(_port);
local.sin_addr.s_addr = inet_addr(_ip);
//允许创建多个端口号相同但IP不同的套接字
int opt = 1;
setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
if(bind(sock, (struct sockaddr*)&local, sizeof(local)) < 0)
{
perror("bind");
return 3;
}
if(listen(sock, 5) < 0)
{
perror("listen");
return 4;
}
return sock;
}
int main(int argc, char* argv[])
{
if(argc != 3)
{
usage(argv[0]);
return 1;
}
int listen_sock = startup(argv[1], atoi(argv[2]));
char buf[10240];
struct sockaddr_in client;
socklen_t len = sizeof(client);
while(1)
{
int new_sock = accept(listen_sock, (struct sockaddr*)&client, &len);
if(new_sock < 0)
{
perror("accept");
continue;
}
//多进程模式
pid_t id = fork();
if(id > 0)
{
//father
close(new_sock);
if(fork() > 0)
{
return 0;
}
}
else if(id == 0)
{
//child
close(listen_sock);
printf("connect... ip is: %s port is: %d \n", inet_ntoa(client.sin_addr), ntohs(client.sin_port));
while(1)
{
ssize_t s = read(new_sock, buf, sizeof(buf)-1);
if(s > 0)
{
buf[s] = '\0';
printf("client say# %s\n",buf);
write(new_sock, buf, strlen(buf));
}
else if(s == 0)
{
printf("client quit ...\n");
break;
}
else
break;
}
return 0;
}
else
{
perror("fork");
close(listen_sock);
return 0;
}
}
return 0;
}
多线程（HTTP）版本：
#include<unistd.h>
#include<stdio.h>
#include<stdlib.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<string.h>
static void usage(const char* proc)
{
printf("%s [ip] [port]", proc);
}
int startup(const char* _ip, int _port)
{
int sock = socket(AF_INET, SOCK_STREAM, 0);
if(sock < 0)
{
perror("socket");
return 2;
}
struct sockaddr_in local;
local.sin_family = AF_INET;
local.sin_port = htons(_port);
local.sin_addr.s_addr = inet_addr(_ip);
//允许创建多个端口号相同但IP不同的套接字
int opt = 1;
setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
if(bind(sock, (struct sockaddr*)&local, sizeof(local)) < 0)
{
perror("bind");
return 3;
}
if(listen(sock, 5) < 0)
{
perror("listen");
return 4;
}
return sock;
}
void* handler(void* arg)
{
char buf[10240];
int newsock = (int)arg;
//printf("connect... ip is: %s port is: %d \n", inet_ntoa(client.sin_addr), ntohs(client.sin_port));
while(1)
{
ssize_t s = read(newsock, buf, sizeof(buf)-1);
if(s > 0)
{
const char* msg = "HTTP/1.1 200 OK\r\n\r\n<html><h1>hello world</h1></html>\r\n";
buf[s] = '\0';
printf("- message:%s\n ",buf);
write(newsock, msg, strlen(msg));
}
else if(s == 0)
{
printf("client quit ...\n");
break;
}
else
break;
}
}
int main(int argc, char* argv[])
{
if(argc != 3)
{
usage(argv[0]);
return 1;
}
int listen_sock = startup(argv[1], atoi(argv[2]));
//char buf[10240];
struct sockaddr_in client;
socklen_t len = sizeof(client);
while(1)
{
int new_sock = accept(listen_sock, (struct sockaddr*)&client, &len);
if(new_sock < 0)
{
perror("accept");
return 2;
}
printf("connect success...\n ip is: %s port is: %d \n", inet_ntoa(client.sin_addr), ntohs(client.sin_port));
//多线程模式
pthread_t tid;
if(pthread_create(&tid, NULL, handler, (void*)new_sock)<0)
{
perror("pthread");
return 3;
}
pthread_detach(&tid);
}
return 0;
}
效果如图：
