15-6-web-main.cpp

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include <cassert>
#include <sys/epoll.h>

#include "14-2-locker.h"
#include "15-3-threadpool.h"
#include "15-4-http_conn.h"

#define MAX_FD 65535
#define MAX_EVENT_NUMBER 10000

extern int addfd(int epollfd, int fd, bool one_shot);
extern int removefd(int epollfd, int fd);

void addsig(int sig, void(handler)(int), bool restart = true)
{
    struct sigaction sa;
    memset(&sa, '\0', sizeof(sa));
    sa.sa_handler = handler;
    if (restart) 
    {
        sa.sa_flags |= SA_RESTART;
    }
    sigfillset(&sa.sa_mask);
    assert(sigaction(sig, &sa, NULL) != -1);
}

void show_error(int connfd, const char * info)
{
    fprintf(stderr, "%s", info);
    send(connfd, info, strlen(info), 0);
    close(connfd);
}

int main(int argc, char *argv[])
{
    if (argc <=2) 
    {
        fprintf(stdout, "usage: %s ip_address port_number\n", basename(argv[0]));
        return 1;
    }

    const char *ip = argv[1];
    int port = atoi(argv[2]);
    
    //ignore SIGPIPE signal
    addsig(SIGPIPE, SIG_IGN);

    //create threadpool
    threadpool<http_conn> *pool = NULL;
    try
    {
        pool = new threadpool<http_conn>;
    }
    catch(...)
    {
        return 1;
    }

    //inital allocate a http_conn for each client connection
    http_conn * users = new http_conn[MAX_FD];
    assert(users);

    int listenfd = socket(PF_INET, SOCK_STREAM, 0);
    assert(listenfd >= 0);
    struct linger tmp = {1,0};
    setsockopt(listenfd, SOL_SOCKET, SO_LINGER, &tmp, sizeof(tmp));

    int ret = 0;
    struct sockaddr_in address;
    bzero(&address, sizeof(address));
    address.sin_family = AF_INET;
    inet_pton(AF_INET, ip, &address.sin_addr);
    address.sin_port = htons(port);

    ret = bind(listenfd, (struct sockaddr *)&address, sizeof(address));
    assert(ret >= 0);

    ret = listen(listenfd, 5);
    assert(ret >= 0);

    epoll_event events[MAX_EVENT_NUMBER];
    int epollfd = epoll_create(5);
    assert(epollfd != -1);
    addfd(epollfd, listenfd, false);
    http_conn::m_epollfd = epollfd;

    while(true)
    {
        int number = epoll_wait(epollfd, events, MAX_EVENT_NUMBER, -1);
        if ((number < 0) && (errno != EINTR)) 
        {
            fprintf(stderr, "epoll failure\n");
            break;
        }

        for (int i = 0; i < number; i ++)
        {
            int sockfd = events[i].data.fd;
            if (sockfd == listenfd) 
            {
                struct sockaddr_in client_address;
                socklen_t client_addrlength = sizeof(client_address);
                int connfd = accept(listenfd, (struct sockaddr *)&client_address, &client_addrlength);
                if (connfd < 0) 
                {
                    fprintf(stderr, "errno is: %d", errno);
                    continue;
                }
                if (http_conn::m_user_count >= MAX_FD) 
                {
                    show_error(connfd, "Internal server busy");
                    continue;
                }

                //initial client conneciton
                users[connfd].init(connfd, client_address);
            }

            else if (events[i].events & (EPOLLRDHUP | EPOLLHUP | EPOLLERR)) 
            {
                //if abnormal, close close connection directly
                users[sockfd].close_conn();
            }
            else if (events[i].events & EPOLLIN) 
            {
                if (users[sockfd].read()) 
                {
                    pool->append(users + sockfd);
                }
                else
                {
                    users[sockfd].close_conn();
                }
            }
            else if (events[i].events & EPOLLOUT) 
            {
                //
                if (!users[sockfd].write()) 
                {
                    users[sockfd].close_conn();
                }
            }
            else
            {
            }
        }
    }
    close(epollfd);
    close(listenfd);
    delete [] users;
    delete pool;
    return 0;
}