Style: code style

adapter/outbound/util.go

@@ -0,0 +1,72 @@
+package outbound
+
+import (
+	"bytes"
+	"crypto/tls"
+	"net"
+	"strconv"
+	"sync"
+	"time"
+
+	"github.com/Dreamacro/clash/component/resolver"
+	C "github.com/Dreamacro/clash/constant"
+	"github.com/Dreamacro/clash/transport/socks5"
+)
+
+var (
+	globalClientSessionCache tls.ClientSessionCache
+	once                     sync.Once
+)
+
+func tcpKeepAlive(c net.Conn) {
+	if tcp, ok := c.(*net.TCPConn); ok {
+		tcp.SetKeepAlive(true)
+		tcp.SetKeepAlivePeriod(30 * time.Second)
+	}
+}
+
+func getClientSessionCache() tls.ClientSessionCache {
+	once.Do(func() {
+		globalClientSessionCache = tls.NewLRUClientSessionCache(128)
+	})
+	return globalClientSessionCache
+}
+
+func serializesSocksAddr(metadata *C.Metadata) []byte {
+	var buf [][]byte
+	aType := uint8(metadata.AddrType)
+	p, _ := strconv.Atoi(metadata.DstPort)
+	port := []byte{uint8(p >> 8), uint8(p & 0xff)}
+	switch metadata.AddrType {
+	case socks5.AtypDomainName:
+		len := uint8(len(metadata.Host))
+		host := []byte(metadata.Host)
+		buf = [][]byte{{aType, len}, host, port}
+	case socks5.AtypIPv4:
+		host := metadata.DstIP.To4()
+		buf = [][]byte{{aType}, host, port}
+	case socks5.AtypIPv6:
+		host := metadata.DstIP.To16()
+		buf = [][]byte{{aType}, host, port}
+	}
+	return bytes.Join(buf, nil)
+}
+
+func resolveUDPAddr(network, address string) (*net.UDPAddr, error) {
+	host, port, err := net.SplitHostPort(address)
+	if err != nil {
+		return nil, err
+	}
+
+	ip, err := resolver.ResolveIP(host)
+	if err != nil {
+		return nil, err
+	}
+	return net.ResolveUDPAddr(network, net.JoinHostPort(ip.String(), port))
+}
+
+func safeConnClose(c net.Conn, err error) {
+	if err != nil {
+		c.Close()
+	}
+}