线程版服务器实现（pthread

线程版服务器实现（pthread_server）

用到的所有方法所需要的参数可以在wrap.c文件中查询，wrap中找不到的直接通过man手册查询

1.首先介绍一下我自己写的包裹文件，里面有各种在可能要用到的方法

wrap.c:

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <strings.h>void perr_exit(const char *s)
{perror(s);exit(-1);
}int Accept(int fd, struct sockaddr *sa, socklen_t *salenptr)
{int n;again:if ((n = accept(fd, sa, salenptr)) < 0) {if ((errno == ECONNABORTED) || (errno == EINTR))//如果是被信号中断和软件层次中断,不能退出goto again;elseperr_exit("accept error");}return n;
}int Bind(int fd, const struct sockaddr *sa, socklen_t salen)
{int n;if ((n = bind(fd, sa, salen)) < 0)perr_exit("bind error");return n;
}int Connect(int fd, const struct sockaddr *sa, socklen_t salen)
{int n;if ((n = connect(fd, sa, salen)) < 0)perr_exit("connect error");return n;
}int Listen(int fd, int backlog)
{int n;if ((n = listen(fd, backlog)) < 0)perr_exit("listen error");return n;
}int Socket(int family, int type, int protocol)
{int n;if ((n = socket(family, type, protocol)) < 0)perr_exit("socket error");return n;
}ssize_t Read(int fd, void *ptr, size_t nbytes)
{ssize_t n;again:if ( (n = read(fd, ptr, nbytes)) == -1) {if (errno == EINTR)//如果是被信号中断,不应该退出goto again;elsereturn -1;}return n;
}ssize_t Write(int fd, const void *ptr, size_t nbytes)
{ssize_t n;again:if ( (n = write(fd, ptr, nbytes)) == -1) {if (errno == EINTR)goto again;elsereturn -1;}return n;
}int Close(int fd)
{int n;if ((n = close(fd)) == -1)perr_exit("close error");return n;
}/*参三: 应该读取固定的字节数数据*/
ssize_t Readn(int fd, void *vptr, size_t n)
{size_t  nleft;              //usigned int 剩余未读取的字节数ssize_t nread;              //int 实际读到的字节数char   *ptr;ptr = vptr;nleft = n;while (nleft > 0) {if ((nread = read(fd, ptr, nleft)) < 0) {if (errno == EINTR)nread = 0;elsereturn -1;} else if (nread == 0)break;nleft -= nread;ptr += nread;}return n - nleft;
}
/*:固定的字节数数据*/
ssize_t Writen(int fd, const void *vptr, size_t n)
{size_t nleft;ssize_t nwritten;const char *ptr;ptr = vptr;nleft = n;while (nleft > 0) {if ( (nwritten = write(fd, ptr, nleft)) <= 0) {if (nwritten < 0 && errno == EINTR)nwritten = 0;elsereturn -1;}nleft -= nwritten;ptr += nwritten;}return n;
}static ssize_t my_read(int fd, char *ptr)
{static int read_cnt;static char *read_ptr;static char read_buf[100];if (read_cnt <= 0) {
again:if ( (read_cnt = read(fd, read_buf, sizeof(read_buf))) < 0) {if (errno == EINTR)goto again;return -1;} else if (read_cnt == 0)return 0;read_ptr = read_buf;}read_cnt--;*ptr = *read_ptr++;return 1;
}ssize_t Readline(int fd, void *vptr, size_t maxlen)
{ssize_t n, rc;char    c, *ptr;ptr = vptr;for (n = 1; n < maxlen; n++) {if ( (rc = my_read(fd, &c)) == 1) {*ptr++ = c;if (c  == '\n')break;} else if (rc == 0) {*ptr = 0;return n - 1;} elsereturn -1;}*ptr  = 0;return n;
}int tcp4bind(short port,const char *IP)
{struct sockaddr_in serv_addr;int lfd = Socket(AF_INET,SOCK_STREAM,0);bzero(&serv_addr,sizeof(serv_addr));if(IP == NULL){//如果这样使用 0.0.0.0,任意ip将可以连接serv_addr.sin_addr.s_addr = INADDR_ANY;}else{if(inet_pton(AF_INET,IP,&serv_addr.sin_addr.s_addr) <= 0){perror(IP);//转换失败exit(1);}}serv_addr.sin_family = AF_INET;serv_addr.sin_port   = htons(port);// int opt = 1;//setsockopt(lfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));Bind(lfd,(struct sockaddr *)&serv_addr,sizeof(serv_addr));return lfd;
}

wrap.h:

#ifndef __WRAP_H_
#define __WRAP_H_
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <strings.h>void perr_exit(const char *s);
int Accept(int fd, struct sockaddr *sa, socklen_t *salenptr);
int Bind(int fd, const struct sockaddr *sa, socklen_t salen);
int Connect(int fd, const struct sockaddr *sa, socklen_t salen);
int Listen(int fd, int backlog);
int Socket(int family, int type, int protocol);
ssize_t Read(int fd, void *ptr, size_t nbytes);
ssize_t Write(int fd, const void *ptr, size_t nbytes);
int Close(int fd);
ssize_t Readn(int fd, void *vptr, size_t n);
ssize_t Writen(int fd, const void *vptr, size_t n);
ssize_t my_read(int fd, char *ptr);
ssize_t Readline(int fd, void *vptr, size_t maxlen);
int tcp4bind(short port,const char *IP);
#endif

2.将这两个文件放到线程服务器源文件的同一目录中，后面需要用到

3.第一步：创建套接字并且绑定

int main(int argc,char *argv[])

由上可见，argc是用户输入终端的参数个数，argv[]表示用户输入终端的信息，argv[0]是./a.out，argv[1]是端口号，如果argc小于2，表示没有传入端口号，退出即可，如下所示：

if(argc < 2)
{printf("argc < 2???   \n ./a.out 8000 \n");return 0;
}

将传入的字符型端口转为short型，如下所示：

short port=atoi(argv[1]);

然后调用wrap.c中的创建套接字并绑定方法“tcp4bind”，参数NULL表示绑定本地所有的ip地址，调用完后返回一个监听套接字，如下所示：

int lfd = tcp4bind(port,NULL);//创建套接字 绑定

4.第二步：开始监听，一样用wrap的方法，如下所示：

Listen(lfd,128);

5.第三步：开始提取

建立一个结构体保存提取的客户端信息，如下所示：

struct sockaddr_in cliaddr;

调用wrap中的提取方法，将提取到的信息放到上面的结构体（只要看到ipv4的结构体，都要转成通配地址，用（struct sockaddr *）强转）中，len是cliaddr的大小，如下所示：

socklen_t len = sizeof(cliaddr);

int cfd = Accept(lfd,(struct sockaddr *)&cliaddr,&len);

6.主线程负责监听，子线程负责服务客户端

所以，提取成功后要创建一个子线程，如下所示：

pthread_t pthid;
pthread_create(&pthid,&attr,client_fun,info);

info是一个结构体，表示要传两个参数给子线程，结构体定义和初始化如下：

typedef struct c_info
{int cfd;struct sockaddr_in cliaddr;
}CINFO;CINFO *info;info = malloc(sizeof(CINFO));info->cfd = cfd;
info->cliaddr= cliaddr;

client_fun是线程回调函数，表示子线程针对客户端要干的事情，如下所示：

void* client_fun(void *arg)
{CINFO *info = (CINFO *)arg;char ip[16]="";printf("new client ip=%s port=%d\n",inet_ntop(AF_INET,&(info->cliaddr.sin_addr.s_addr),ip,16),ntohs(info->cliaddr.sin_port));while(1){char buf[1024]="";int count=0;count = read(info->cfd,buf,sizeof(buf));if(count < 0){perror("");break;	}else if(count == 0){printf("client close\n");break;}else{printf("%s\n", buf);write(info->cfd,buf,count);	}}close(info->cfd);free(info);
}

7.子线程工作完成后，如何回收？

设置一下线程分离属性就可以了，如下所示：

pthread_attr_t attr;
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr,PTHREAD_CREATE_DETACHED);

在这里使用（&attr），如下所示：

pthread_create(&pthid,&attr,client_fun,info);

这样的话，子线程退出，系统会自动回收子线程！

8.“1_pthread_server.c”的完整代码如下所示：

#include <stdio.h>
#include <pthread.h>
#include "wrap.h"typedef struct c_info
{int cfd;struct sockaddr_in cliaddr;
}CINFO;void* client_fun(void *arg);int main(int argc, char *argv[])
{if(argc < 2){printf("argc < 2???   \n");return 0;}pthread_attr_t attr;pthread_attr_init(&attr);pthread_attr_setdetachstate(&attr,PTHREAD_CREATE_DETACHED);short port = atoi(argv[1]);int lfd = tcp4bind(port,NULL);//创建套接字 绑定 Listen(lfd,128);struct sockaddr_in cliaddr;socklen_t len = sizeof(cliaddr);CINFO *info;while(1){int cfd = Accept(lfd,(struct sockaddr *)&cliaddr,&len);char ip[16]="";pthread_t pthid;info = malloc(sizeof(CINFO));info->cfd = cfd;info->cliaddr= cliaddr;pthread_create(&pthid,&attr,client_fun,info);}return 0;
}void* client_fun(void *arg)
{CINFO *info = (CINFO *)arg;char ip[16]="";printf("new client ip=%s port=%d\n",inet_ntop(AF_INET,&(info->cliaddr.sin_addr.s_addr),ip,16),ntohs(info->cliaddr.sin_port));while(1){char buf[1024]="";int count=0;count = read(info->cfd,buf,sizeof(buf));if(count < 0){perror("");break;	}else if(count == 0){printf("client close\n");break;}else{printf("%s\n", buf);write(info->cfd,buf,count);	}}close(info->cfd);free(info);
}

退出vim编辑器，gcc编译一下：