Files
stopwait_chat_ipv6/windows_chat.c
2025-12-26 15:22:17 +08:00

134 lines
3.4 KiB
C

#include <stdio.h>
#include <string.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#include <process.h>
#include "common.h"
#pragma comment(lib, "ws2_32.lib")
typedef struct {
SOCKET sock;
uint8_t *recv_seq;
struct sockaddr_in6 *peer;
} recv_args;
void receiver(void *arg) {
recv_args *a = (recv_args *)arg;
while (1) {
fd_set fds;
FD_ZERO(&fds);
FD_SET(a->sock, &fds);
TIMEVAL tv = {0, 100000};
if (select(a->sock + 1, &fds, NULL, NULL, &tv) > 0) {
struct packet rcv;
recvfrom(a->sock, (char *)&rcv, sizeof(rcv), 0, NULL, NULL);
rcv.payload[sizeof(rcv.payload) - 1] = '\0';
if (rcv.type == TYPE_DATA) {
if (rcv.seq == *a->recv_seq) {
printf("\npeer: %s\n", rcv.payload);
*a->recv_seq ^= 1;
}
rcv.type = TYPE_ACK;
sendto(a->sock, (char *)&rcv, 2, 0,
(struct sockaddr *)a->peer, sizeof(*a->peer));
}
}
}
}
void send_with_stopwait(SOCKET sock,
struct sockaddr_in6 *peer,
struct packet *pkt, int pkt_len)
{
int addr_len = sizeof(*peer);
while (1) {
printf("Sending seq %d\n", pkt->seq);
sendto(sock, (char *)pkt, pkt_len, 0,
(struct sockaddr *)peer, addr_len);
fd_set fds;
FD_ZERO(&fds);
FD_SET(sock, &fds);
TIMEVAL tv;
tv.tv_sec = TIMEOUT_SEC;
tv.tv_usec = 0;
int ret = select(sock + 1, &fds, NULL, NULL, &tv);
printf("Select returned %d\n", ret);
if (ret > 0) {
struct packet ack;
recvfrom(sock, (char *)&ack, sizeof(ack), 0, NULL, NULL);
printf("Received ack seq %d type %d\n", ack.seq, ack.type);
if (ack.type == TYPE_ACK && ack.seq == pkt->seq) {
printf("Correct ACK received\n");
return;
}
}
printf("[timeout] retransmit\n");
}
}
int main(int argc, char *argv[])
{
if (argc != 2) {
printf("用法: %s <对方IPv6地址>\n", argv[0]);
return 1;
}
WSADATA wsa;
WSAStartup(MAKEWORD(2, 2), &wsa);
SOCKET sock = socket(AF_INET6, SOCK_DGRAM, 0);
struct sockaddr_in6 local = {0};
local.sin6_family = AF_INET6;
local.sin6_addr = in6addr_any;
local.sin6_port = htons(PORT);
bind(sock, (struct sockaddr *)&local, sizeof(local));
struct sockaddr_in6 peer = {0};
peer.sin6_family = AF_INET6;
peer.sin6_port = htons(PORT);
if (inet_pton(AF_INET6, argv[1], &peer.sin6_addr) != 1) {
printf("无效的 IPv6 地址\n");
return 1;
}
uint8_t send_seq = 0;
uint8_t recv_seq = 0;
struct packet pkt;
memset(&pkt, 0, sizeof(pkt));
printf("Windows UDP IPv6 Stop-Wait Chat\n");
// 启动接收线程
recv_args args = {sock, &recv_seq, &peer};
_beginthread(receiver, 0, &args);
while (1) {
printf(">> ");
if (!fgets(pkt.payload, sizeof(pkt.payload), stdin))
break;
size_t len = strlen(pkt.payload);
if (len > 0 && pkt.payload[len - 1] == '\n') pkt.payload[len - 1] = '\0';
pkt.seq = send_seq;
pkt.type = TYPE_DATA;
int pkt_len = 2 + strlen(pkt.payload) + 1;
send_with_stopwait(sock, &peer, &pkt, pkt_len);
send_seq ^= 1;
}
closesocket(sock);
WSACleanup();
return 0;
}