一、并发服务器的 优点
- 当有多个客户端 需要同时连接 该服务器时,需要服务器分时复用的 处理 各客户端发送过来的数据;
- 当客服端退出的时候,服务器需要知道 该客户端已经退出了;
- 以下有两种 并发服务器的设计方式,优点各异,可根据需求选择适当的 方式;
二、多进程并发服务器
1、服务器 源码
#include "net_pth.h"
#include <signal.h>
void sig_chile_handle(int s);
void cli_data_handle(void *agc);
void sig_chile_handle(int s){
if(SIGCHLD == s){
waitpid(-1,NULL,WNOHANG);
}
}
int main(int argc, const char *argv[])
{
int fd = -1;
struct sockaddr_in sin;
signal(SIGCHLD,sig_chile_handle);
/* 1、创建socket fd */
if((fd = socket(AF_INET , SOCK_STREAM,0)) < 0 ){
perror("socket");
exit(1);
}
/*优化:允许客户端快速重连*/
int b_reuse = -1;
setsockopt(fd,SOL_SOCKET,SO_REUSEADDR,&b_reuse,sizeof(int));
/* 2、绑定 */
/* 2.1 填充 struct sockaddr_in 结构体变量 */
bzero(&sin,sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_port = htons(SERV_PORT);
#if 1
sin.sin_addr.s_addr = htonl(INADDR_ANY);//优化1:服务器可绑定任何IP
#else
if( inet_pton( AF_INET , SERV_IP_ADDR , (void*)&sin.sin_addr) != 1) {
perror("inet_pton");
exit(1);
}
#endif
/* 2.2 绑定 */
if(bind(fd , (struct sockaddr*)&sin , sizeof(sin)) < 0){
perror("bind");
exit(1);
}
/* 3、调用listen() 把主动套接字变成被动套接字 */
if(listen(fd , BACKLOG) < 0){
perror("listen");
exit(1);
}
printf("server starting ... OK !\n");
/* 4、阻塞等待客户端 连接请求 */
struct sockaddr_in cin;
socklen_t addrlen = sizeof(cin);
int newfd = -1;
while(1){
pid_t pid = -1;
newfd = accept(fd ,(struct sockaddr *)&cin,&addrlen);//可以接收 客户端的信息
if(newfd <0 ){
perror("accept");
exit(1);
}//得到客户端信息
if((pid = fork()) < 0){ //创建子进程
perror("fork");
break;
}else if(pid ==0 ){ //子进程
char ipv4_addr[16];
close(fd);
if(!inet_ntop(AF_INET,(void*)&cin.sin_addr,ipv4_addr,sizeof(cin))){
perror("inet_ntop");
exit(1);
}
printf("Client(%s:%d) is connected \n",ipv4_addr,htons(cin.sin_port));
cli_data_handle(&newfd); // 子进程执行函数
return 0;
}else{ //父进程
close(newfd);
}
}
close(fd);
return 0;
}
void cli_data_handle(void *agc)
{
int newfd =*(int*)agc;
int ret = -1;
char buf[BUFSIZ];
printf("handle %d \n",newfd);
while(1)
{
bzero(buf,sizeof(buf));
do{
ret = read(newfd , buf ,BUFSIZ-1);
}while(ret <0 && EINTR == errno);
if(ret < 0){
perror("read");
exit(1);
}
if(!ret){
break;
}
printf("Client (fd-%d ) Receive data : %s\n",newfd,buf);
if(!strncasecmp(buf,QUIT_STR, strlen(QUIT_STR))){
printf("Client (fd-%d) is exiting !\n",newfd);
break;
}
}
close(newfd);
}
2、客户端 源码
#include "net_pth.h"
void usage(const char* s){
printf("\n %s serv_ip ser_port \n",s);
printf("\n\t serv_ip: server ip address");
printf("\r\n serv_port: server port(>5000)\n\n");
}
int main(int argc, const char *argv[])
{
int fd = -1;
int port = 0;
struct sockaddr_in sin;
/* 1、创建socket fd */
if((fd = socket(AF_INET , SOCK_STREAM,0)) < 0 ){
perror("socket");
exit(1);
}
if(argc != 3 ){
usage(argv[0]);
exit(1);
}
port = atoi(argv[2]);
if (port < 5000){
usage(argv[0]);
exit(1);
}
/* 2、连接服务器 */
/* 2.1 填充 struct sockaddr_in 结构体变量 */
bzero(&sin,sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_port = htons(port);
#if 0
sin.sin_addr.s_addr = inet_addr(SERV_IP_ADDR);
#else
if(inet_pton( AF_INET , argv[1] , (void*)&sin.sin_addr) != 1) {
perror("inet_pton");
exit(1);
}
printf("Client staring .... OK! \n");
#endif
/* 2、2 连接服务器 */
if( connect(fd ,(struct sockaddr *)&sin,sizeof(sin)) < 0){
perror("connect");
exit(1);
}
/* 3、读写数据*/
char buf[BUFSIZ];
while(1){
bzero(buf, sizeof(buf));
if(fgets(buf,BUFSIZ-1,stdin) == NULL){
continue;
}
write(fd , buf , strlen(buf));
if(!strncasecmp(buf,QUIT_STR,strlen(QUIT_STR))){
break;
}
}
/* 4、关闭套接字*/
close(fd);
}
3、所使用的 头文件
#ifndef __NET_LOOP_H__
#define __NET_LOOP_H__
#include <string.h>
#include <errno.h>
#include <strings.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <sys/wait.h>
#define SERV_PORT 5001
#define SERV_IP_ADDR "192.168.196.132"
#define BACKLOG 5
#define QUIT_STR "quit"
#endif
三、多线程并发服务器
1、服务器 源码
#include "net_pth.h"
#include <pthread.h>
void cli_data_handle(char *agc);
int main(int argc, const char *argv[])
{
int fd = -1;
struct sockaddr_in sin;
/* 1、创建socket fd */
if((fd = socket(AF_INET , SOCK_STREAM,0)) < 0 ){
perror("socket");
exit(1);
}
/*优化:允许客户端快速重连*/
int b_reuse = -1;
setsockopt(fd,SOL_SOCKET,SO_REUSEADDR,&b_reuse,sizeof(int));
/* 2、绑定 */
/* 2.1 填充 struct sockaddr_in 结构体变量 */
bzero(&sin,sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_port = htons(SERV_PORT);
#if 1
sin.sin_addr.s_addr = htonl(INADDR_ANY);//优化1:服务器可绑定任何IP
#else
if( inet_pton( AF_INET , SERV_IP_ADDR , (void*)&sin.sin_addr) != 1) {
perror("inet_pton");
exit(1);
}
#endif
/* 2.2 绑定 */
if(bind(fd , (struct sockaddr*)&sin , sizeof(sin)) < 0){
perror("bind");
exit(1);
}
/* 3、调用listen() 把主动套接字变成被动套接字 */
if(listen(fd , BACKLOG) < 0){
perror("listen");
exit(1);
}
printf("server starting ... OK !\n");
/* 4、阻塞等待客户端 连接请求 */
pthread_t tid;
struct sockaddr_in cin;
socklen_t addrlen = sizeof(cin);
int newfd = -1;
while(1){
#if 0
newfd = accept(fd ,NULL,NULL);//可以接受 客户端的信息
if(newfd <0 ){
perror("accept");
exit(1);
}
#else
newfd = accept(fd ,(struct sockaddr *)&cin,&addrlen);//可以接收 客户端的信息
if(newfd <0 ){
perror("accept");
exit(1);
}//得到客户端信息
char ipv4_addr[16];
if(!inet_ntop(AF_INET,(void*)&cin.sin_addr,ipv4_addr,sizeof(cin))){
perror("inet_ntop");
exit(1);
}
printf("Client(%s:%d) is connected \n",ipv4_addr,htons(cin.sin_port));
pthread_create(&tid,NULL,(void*)cli_data_handle,(void*)&newfd);//创建线程
#endif
}
close(fd);
return 0;
}
void cli_data_handle(char *agc)
{
int newfd =*(int*)agc;
int ret = -1;
char buf[BUFSIZ];
printf("handle pthead %d \n",newfd);
while(1)
{
bzero(buf,sizeof(buf));
do{
ret = read(newfd , buf ,BUFSIZ-1);
}while(ret <0 && EINTR == errno);
if(ret < 0){
perror("read");
exit(1);
}
if(!ret){
break;
}
printf("Client (fd-%d ) Receive data : %s\n",newfd,buf);
if(!strncasecmp(buf,QUIT_STR, strlen(QUIT_STR))){
printf("Client (fd-%d) is exiting !\n",newfd);
break;
}
}
close(newfd);
}
2、客户端 源码
#include "net_pth.h"
void usage(const char* s){
printf("\n %s serv_ip ser_port \n",s);
printf("\n\t serv_ip: server ip address");
printf("\r\n serv_port: server port(>5000)\n\n");
}
int main(int argc, const char *argv[])
{
int fd = -1;
int port = 0;
struct sockaddr_in sin;
/* 1、创建socket fd */
if((fd = socket(AF_INET , SOCK_STREAM,0)) < 0 ){
perror("socket");
exit(1);
}
if(argc != 3 ){
usage(argv[0]);
exit(1);
}
port = atoi(argv[2]);
if (port < 5000){
usage(argv[0]);
exit(1);
}
/* 2、连接服务器 */
/* 2.1 填充 struct sockaddr_in 结构体变量 */
bzero(&sin,sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_port = htons(port);
#if 0
sin.sin_addr.s_addr = inet_addr(SERV_IP_ADDR);
#else
if(inet_pton( AF_INET , argv[1] , (void*)&sin.sin_addr) != 1) {
perror("inet_pton");
exit(1);
}
printf("Client staring .... OK! \n");
#endif
/* 2、2 连接服务器 */
if( connect(fd ,(struct sockaddr *)&sin,sizeof(sin)) < 0){
perror("connect");
exit(1);
}
/* 3、读写数据*/
char buf[BUFSIZ];
while(1){
bzero(buf, sizeof(buf));
if(fgets(buf,BUFSIZ-1,stdin) == NULL){
continue;
}
write(fd , buf , strlen(buf));
if(!strncasecmp(buf,QUIT_STR,strlen(QUIT_STR))){
break;
}
}
/* 4、关闭套接字*/
close(fd);
}
3、所用来的 头文件 以及宏
#ifndef __NET_LOOP_H__
#define __NET_LOOP_H__
#include <string.h>
#include <errno.h>
#include <strings.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#define SERV_PORT 5001
#define SERV_IP_ADDR "192.168.196.132"
#define BACKLOG 5
#define QUIT_STR "quit"
#endif
四、总结