104 lines
2.1 KiB
C
104 lines
2.1 KiB
C
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#include <netdb.h>
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#include <stdio.h>
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#include <sys/socket.h>
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#include <sys/types.h>
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#include <unistd.h>
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#define PORT "1025"
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#define BACKLOG 4
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#define BUF_SIZE 20
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int create_server_sock(char* port) {
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struct addrinfo hints = {
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.ai_family = AF_INET6,
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.ai_socktype = SOCK_STREAM,
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.ai_flags = AI_PASSIVE || AI_V4MAPPED
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};
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struct addrinfo *res;
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int err = getaddrinfo(NULL, port, &hints, &res);
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if (err != 0) {
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fprintf(stderr, "gai_err %s\n", gai_strerror(err));
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_exit(1);
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}
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int sfd;
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struct addrinfo* cur = res;
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for (; cur != NULL; cur = cur->ai_next) {
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// create socket
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sfd = socket(cur->ai_family, cur->ai_socktype, cur->ai_protocol);
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if (sfd == -1) {
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perror("socket");
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continue;
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}
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int val = 1;
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err = setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
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if (err == -1) {
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perror("setsockopt");
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close(sfd);
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continue;
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}
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// Bind
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err = bind(sfd, cur->ai_addr, cur->ai_addrlen);
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if (err == -1) {
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perror("bind");
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close(sfd);
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continue;
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}
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// Listen
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err = listen(sfd, BACKLOG);
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if (err == -1) {
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perror("listen");
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close(sfd);
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continue;
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}
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break;
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}
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freeaddrinfo(res);
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if (cur == NULL) {
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fprintf(stderr, "failed to create socket\n");
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close(sfd);
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_exit(1);
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}
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return sfd;
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}
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int main() {
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int sfd = create_server_sock(PORT);
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struct sockaddr_storage client_addr;
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socklen_t client_addr_len = sizeof(client_addr);
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int cfd = accept(sfd, (struct sockaddr*) &client_addr, &client_addr_len);
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if (cfd == -1) {
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perror("accept");
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_exit(1);
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}
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int n;
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uint8_t buf[BUF_SIZE];
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while ((n = read(cfd, buf, BUF_SIZE)) > 0) {
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if (n == -1) {
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perror("read");
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_exit(1);
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}
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if (write(STDOUT_FILENO, buf, n) == -1) {
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perror("read");
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_exit(1);
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}
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}
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close(sfd);
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return 0;
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}
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