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| #include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/epoll.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
static const char* request = "GET http://localhost/index.html HTTP/1.1\r\nConnection: keep-alive\r\n\r\nxxxxxxxxxxxx";
int setnonblocking(int fd)
{
int old_option = fcntl(fd, F_GETFL);
int new_option = old_option | O_NONBLOCK;
fcntl(fd, F_SETFL, new_option);
return old_option;
}
void addfd(int epoll_fd, int fd)
{
epoll_event event;
event.data.fd = fd;
event.events = EPOLLOUT | EPOLLET | EPOLLERR;
epoll_ctl(epoll_fd, EPOLL_CTL_ADD, fd, &event);
setnonblocking(fd);
}
bool write_nbytes(int sockfd, const char* buffer, int len)
{
int bytes_write = 0;
printf("write out %d bytes to socket %d\n", len, sockfd);
while (1)
{
bytes_write = send(sockfd, buffer, len, 0);
if (bytes_write == -1)
{
return false;
}
else if (bytes_write == 0)
{
return false;
}
len -= bytes_write;
buffer = buffer + bytes_write;
if (len <= 0)
{
return true;
}
}
}
bool read_once(int sockfd, char* buffer, int len)
{
int bytes_read = 0;
memset(buffer, '\0', len);
bytes_read = recv(sockfd, buffer, len, 0);
if (bytes_read == -1)
{
return false;
}
else if (bytes_read == 0)
{
return false;
}
printf("read in %d bytes from socket %d with content: %s\n", bytes_read, sockfd, buffer);
return true;
}
void start_conn(int epoll_fd, int num, const char* ip, int port)
{
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);
for (int i = 0; i < num; ++i)
{
sleep(1);
int sockfd = socket(PF_INET, SOCK_STREAM, 0);
printf("create 1 sock\n");
if (sockfd < 0)
{
continue;
}
if (connect(sockfd, (struct sockaddr*)&address, sizeof(address)) == 0)
{
printf("build connection %d\n", i);
addfd(epoll_fd, sockfd);
}
}
}
void close_conn(int epoll_fd, int sockfd)
{
epoll_ctl(epoll_fd, EPOLL_CTL_DEL, sockfd, 0);
close(sockfd);
}
int main(int argc, char* argv[])
{
assert(argc == 4);
int epoll_fd = epoll_create(100);
start_conn(epoll_fd, atoi(argv[3]), argv[1], atoi(argv[2]));
epoll_event events[10000];
char buffer[2048];
while (1)
{
int fds = epoll_wait(epoll_fd, events, 10000, 2000);
for (int i = 0; i < fds; i++)
{
int sockfd = events[i].data.fd;
if (events[i].events & EPOLLIN)
{
if (!read_once(sockfd, buffer, 2048))
{
close_conn(epoll_fd, sockfd);
}
struct epoll_event event;
event.events = EPOLLOUT | EPOLLET | EPOLLERR;
event.data.fd = sockfd;
epoll_ctl(epoll_fd, EPOLL_CTL_MOD, sockfd, &event);
}
else if (events[i].events & EPOLLOUT)
{
if (!write_nbytes(sockfd, request, strlen(request)))
{
close_conn(epoll_fd, sockfd);
}
struct epoll_event event;
event.events = EPOLLIN | EPOLLET | EPOLLERR;
event.data.fd = sockfd;
epoll_ctl(epoll_fd, EPOLL_CTL_MOD, sockfd, &event);
}
else if (events[i].events & EPOLLERR)
{
close_conn(epoll_fd, sockfd);
}
}
}
}
|