You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

108 lines
2.5 KiB

//go:build !windows
// +build !windows
package localchat
import (
"encoding/json"
"log"
"net"
)
func SendBroadcast(message UdpMessage) error {
broadcastAddr := GetBroadcastAddr()
addr, err := net.ResolveUDPAddr("udp4", broadcastAddr)
if err != nil {
log.Printf("Failed to resolve UDP address %s: %v", broadcastAddr, err)
return err
}
// 使用本地地址进行连接
localAddr, err := net.ResolveUDPAddr("udp4", "0.0.0.0:0")
if err != nil {
log.Printf("Failed to resolve local UDP address: %v", err)
return err
}
conn, err := net.ListenUDP("udp4", localAddr)
if err != nil {
log.Printf("Failed to listen on UDP address %s: %v", broadcastAddr, err)
return err
}
defer conn.Close()
// 获取本地 IP 地址
localIP, err := GetLocalIP()
log.Printf("本地 IP 地址: %s", localIP)
if err != nil {
log.Printf("Failed to get local IP address: %v", err)
return err
}
message.IP = localIP
data, err := json.Marshal(message)
if err != nil {
log.Printf("Failed to marshal JSON for %s: %v", broadcastAddr, err)
return err
}
_, err = conn.WriteToUDP(data, addr)
if err != nil {
log.Printf("Failed to write to UDP address %s: %v", broadcastAddr, err)
return err
}
log.Printf("发送消息到 %s 成功", broadcastAddr)
return nil
}
// ListenForBroadcast 监听多播消息
func ListenForBroadcast() {
broadcastAddr := GetBroadcastAddr()
addr, err := net.ResolveUDPAddr("udp4", broadcastAddr)
if err != nil {
log.Fatalf("Failed to resolve UDP address: %v", err)
}
// 使用 ListenMulticastUDP 创建多播连接
conn, err := net.ListenMulticastUDP("udp4", nil, addr)
if err != nil {
log.Fatalf("Failed to listen on UDP address: %v", err)
}
defer conn.Close()
// 获取本地 IP 地址
localIP, err := GetLocalIP()
if err != nil {
log.Printf("Failed to get local IP address: %v", err)
}
// 开始监听多播消息
buffer := make([]byte, 1024)
for {
n, remoteAddr, err := conn.ReadFromUDP(buffer)
if err != nil {
log.Printf("Error reading from UDP: %v", err)
continue
}
var udpMsg UdpMessage
err = json.Unmarshal(buffer[:n], &udpMsg)
if err != nil {
log.Printf("Error unmarshalling JSON: %v", err)
continue
}
if udpMsg.IP == localIP {
continue
}
OnlineUsers[udpMsg.IP] = udpMsg
if udpMsg.Type == "file" {
RecieveFile(udpMsg)
}
log.Printf("Received message from %s: %s", remoteAddr, udpMsg.Hostname)
}
}
func GetBroadcastAddr() string {
//return libs.GetUdpAddr()
return "224.0.0.251:20249"
}