【转】常用服务器模型总结

典型代码：
socket
bind
listen
for(;;)
{
    connfd = accept(listenfd, (SA*)&cliaddr, &clilen);
    process_connection(connfd);
    close(connfd);
}

典型代码：
init_address(server_addr)
listenfd = socket(AF_INET,SOCKET_STREAM,0);
bind(listenfd, (SA*)server_addr, sizeof(serveraddr));
listen(listenfd,BACKLOG);
for(;;)
{
    connfd = accept(listenfd, (SA*)&cliaddr, &clilen);
    if(connfd < 0)
    {
        if(EINTR == errno)
            continue;
         else
             //error
    }
 
    if(fork() == 0)
    {
        close(c=listenfd);
        process_connection(connfd); //child process 
        exit(0);
    }
    close(connfd);//parent, close connected socket
}

典型代码：
static pthread_mutex_t *mptr;
void 
my_lock_init(char *pathname)
{
    int   fd;
    pthread_mutexattr_t mattr;
   
    //因为是相关进程所以可以使用/dev/zero设备创建共享内存
    //优势是调用mmap创建共享存储区之前无需一个实际的文件
    //映射/dev/zero自动创建一个指定长度的映射区
    fd = open("/dev/zero", O_RDWR, 0,);
    // 将mptr映射到共享存储区
    mptr = mmap(0, sizeof(pthread_mutex_t), PORT_READ | PORT_WRITE, MAP_SHARED, fd, 0);
    close(fd);
    pthread_mutexattr_init(&mattr);
    pthread_mutexattr_setpshared(&mptr, PTHREAD_PROCESS_SHARED);
    pthread_mutex_init(mptr, &mattr);
}
 
void 
my_lock_wait()
{
    pthread_mutex_lock(mptr);
}
 
void
my_lock_release()
{
    pthread_mutex_unlock(mptr);
}
 
int
main(int argc, char **argv)
{
   //init socket and address
    my_lock_init(pathname);
    for(i = 0; i < nchildren; ++i)
    {
        pids[i] = child_make(i, listenfd, addrlen);
    }
 
    for(;;)
        pause();
}
 
pid_t
child_make(int i, int listenfd, int addrlen)
{
    pid_t pid;
 
    if((pid = fork) > 0)
        return pid;
 
    child_main(i, listenfd, addrlen);
}
 
void 
child_main()
{
    for(;;)
    {
        my_lock_wait();
        connfd = accept(listenfd, chiladdr, &clilen);
        my_lock_release();
        web_child(connfd);
        close(connfd);
    }
}
 

典型代码：
for(;;)
{
    connfd = accept(listenfd, cliaddr, &clilen,);
    pthread_create(&tid, NULL, &doit, (void *)connfd);
}
 
void *
doit(void *arg)
{
    pthread_detach(pthread_self());
    web_child((int)arg);
    close((int)arg)
    return (NULL);
}