채팅 서버 - epoll 버전

 채팅 클라이언트와 이어지는 채팅 서버이다.

 이번엔 리눅스에서 epoll 을 사용해서 간단한 서버 버전을 작성했다.

 CreateTCPServerSocket() 은 The Pocket Guide to TCP/IP Sockets 에 있던 예제를 참조하였다.

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#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <errno.h>

#include <pthread.h>

#include <sys/socket.h>

#include <sys/epoll.h>

#include <sys/types.h>

#include <net/if.h>

#include <arpa/inet.h>

#include <errno.h>

#define SERV_PORT 8787

#define MAX_THREAD_CNT 100

#define MAX_CLI_CNT 10

#define MAX_BUFF_SZ 1024

#define UNUSED 0

#define USED 1

typedef struct {

int sockfd;

int used;

int state;

char recv_buff[1024];

} cli_pool_t;

cli_pool_t cli_pool[MAX_CLI_CNT];

fd_set rset, allset;

int DelClientPool(int idx);

int InitClientPool();

int AddClientPool(int sockfd);

int    CreateTCPServerSocket(unsigned short port);

main()

{

char cliaddr_buff[100];

int cli_fd, sock_fd, clilen;

int i, result, maxfd, s_cnt, idx;

int serv_port, thread_cnt;

char recv_buff[MAX_BUFF_SZ];

struct  sockaddr_in cli_addr;

struct epoll_event *event;

struct epoll_event ev;

int efd;

serv_port = SERV_PORT;

sock_fd = CreateTCPServerSocket(serv_port);

if (sock_fd < 0) {

perror("server socket failed.");

exit(1);

}

thread_cnt = MAX_THREAD_CNT;

efd = epoll_create(MAX_CLI_CNT);

if (efd < 0) {

perror("epoll create error.");

exit(2);

}

event = (struct epoll_event *)malloc(sizeof(struct epoll_event) * MAX_CLI_CNT);

result = InitClientPool(sock_fd);

ev.events = EPOLLIN;

ev.data.fd = result;

epoll_ctl(efd, EPOLL_CTL_ADD, sock_fd, &ev);

clilen = sizeof(cli_addr);

for (;;) {

s_cnt = epoll_wait(efd, event, MAX_CLI_CNT, -1);

if (s_cnt <= 0) {

perror("epoll_wait fail.");

continue;

}

for (i = 0; i < s_cnt; i++) {

if (event[i].data.fd == 0) { // Server sock

cli_fd = accept(sock_fd, (struct sockaddr *)&cli_addr, &clilen);

if (cli_fd <= 0) {

perror("accept fail.");

}

else if (cli_fd > 0) {

result = AddClientPool(cli_fd);

if (result < 0) {

perror("AddClientPool Error");

close(cli_fd);

} else {

ev.events = EPOLLIN;

ev.data.fd = result;

result = epoll_ctl(efd, EPOLL_CTL_ADD, cli_fd, &ev);

}

}

continue;

}

else {

idx = event[i].data.fd;

printf("sockfd(%d) idx(%d), s_cnt(%d)\n", cli_pool[idx].sockfd, idx, s_cnt);

memset(cli_pool[idx].recv_buff, 0x00, sizeof(cli_pool[idx].recv_buff));

result = read(cli_pool[idx].sockfd, cli_pool[idx].recv_buff, sizeof(cli_pool[idx].recv_buff));

if (result < 0) {

printf("ERR : read fail (%d)\n", result);

epoll_ctl(efd, EPOLL_CTL_DEL, cli_pool[idx].sockfd, event);

DelClientPool(idx);

}

else if (result == 0) {

printf("ERR : client disconnect idx(%d)\n", idx);

epoll_ctl(efd, EPOLL_CTL_DEL, cli_pool[idx].sockfd, event);

DelClientPool(idx);

}

else {

for (i = 1; i <= MAX_CLI_CNT; i++) {

if (cli_pool[i].state == USED)

send(cli_pool[i].sockfd, cli_pool[idx].recv_buff, strlen(cli_pool[idx].recv_buff), 0);

}

printf("%s\n", cli_pool[idx].recv_buff);

}

}

}

}

return 0;

}

int InitClientPool(int sockfd)

{

int i;

for (i = 0; i < MAX_CLI_CNT; i++) {

cli_pool[i].sockfd = -1;

cli_pool[i].state == UNUSED;

}

cli_pool[0].sockfd = sockfd;

cli_pool[0].state == USED;

return 0;

}

int AddClientPool(int sockfd)

{

int i;

for (i = 1; i < MAX_CLI_CNT; i++) {

if (cli_pool[i].state == UNUSED) {

cli_pool[i].sockfd = sockfd;

cli_pool[i].state = USED;

return i;

}

}

return -1;

}

int DelClientPool(int idx)

{

close(cli_pool[idx].sockfd);

cli_pool[idx].state = UNUSED;

memset(cli_pool[idx].recv_buff, 0x00, sizeof(cli_pool[idx].recv_buff));

}

int CreateTCPServerSocket(unsigned short port)

{

int sock;

struct sockaddr_in  servaddr;

if ((sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {

printf("socket() failed.\n");

return -1;

}

memset(&servaddr, 0, sizeof(struct sockaddr_in));

servaddr.sin_family = AF_INET;

servaddr.sin_addr.s_addr = htonl(INADDR_ANY);

//  servaddr.sin_addr.s_addr = htonl(inet_addr("127.0.0.1"));

servaddr.sin_port = htons(port);

if (bind(sock, (struct sockaddr *)&servaddr, sizeof(struct sockaddr_in)) < 0) {

printf("Bind() failed.\n");

return -2;

}

if (listen(sock, SOMAXCONN)) {

printf("Listen() failed.\n");

return -3;

}

return sock;

}

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