mirror of
https://github.com/seaweedfs/seaweedfs.git
synced 2024-01-19 02:48:24 +00:00
143 lines
2.3 KiB
Go
143 lines
2.3 KiB
Go
package udptransfer
|
|
|
|
import (
|
|
"encoding/binary"
|
|
"fmt"
|
|
)
|
|
|
|
const (
|
|
_F_NIL = 0
|
|
_F_SYN = 1
|
|
_F_ACK = 1 << 1
|
|
_F_SACK = 1 << 2
|
|
_F_TIME = 1 << 3
|
|
_F_DATA = 1 << 4
|
|
// reserved = 1 << 5
|
|
_F_RESET = 1 << 6
|
|
_F_FIN = 1 << 7
|
|
)
|
|
|
|
var packetTypeNames = map[byte]string{
|
|
0: "NOOP",
|
|
1: "SYN",
|
|
2: "ACK",
|
|
3: "SYN+ACK",
|
|
4: "SACK",
|
|
8: "TIME",
|
|
12: "SACK+TIME",
|
|
16: "DATA",
|
|
64: "RESET",
|
|
128: "FIN",
|
|
192: "FIN+RESET",
|
|
}
|
|
|
|
const (
|
|
_S_FIN = iota
|
|
_S_FIN0
|
|
_S_FIN1
|
|
_S_SYN0
|
|
_S_SYN1
|
|
_S_EST0
|
|
_S_EST1
|
|
)
|
|
|
|
// Magic-6 | TH-10 | CH-10 | payload
|
|
const (
|
|
_MAGIC_SIZE = 6
|
|
_TH_SIZE = 10 + _MAGIC_SIZE
|
|
_CH_SIZE = 10
|
|
_AH_SIZE = _TH_SIZE + _CH_SIZE
|
|
)
|
|
|
|
const (
|
|
// Max UDP payload: 1500 MTU - 20 IP hdr - 8 UDP hdr = 1472 bytes
|
|
// Then: MSS = 1472-26 = 1446
|
|
// And For ADSL: 1446-8 = 1438
|
|
_MSS = 1438
|
|
)
|
|
|
|
const (
|
|
_SENT_OK = 0xff
|
|
)
|
|
|
|
type packet struct {
|
|
seq uint32
|
|
ack uint32
|
|
flag uint8
|
|
scnt uint8
|
|
payload []byte
|
|
buffer []byte
|
|
}
|
|
|
|
func (p *packet) marshall(id connID) []byte {
|
|
buf := p.buffer
|
|
if buf == nil {
|
|
buf = make([]byte, _AH_SIZE+len(p.payload))
|
|
copy(buf[_TH_SIZE+10:], p.payload)
|
|
}
|
|
binary.BigEndian.PutUint16(buf[_MAGIC_SIZE:], uint16(len(buf)))
|
|
binary.BigEndian.PutUint32(buf[_MAGIC_SIZE+2:], id.rid)
|
|
binary.BigEndian.PutUint32(buf[_MAGIC_SIZE+6:], id.lid)
|
|
binary.BigEndian.PutUint32(buf[_TH_SIZE:], p.seq)
|
|
binary.BigEndian.PutUint32(buf[_TH_SIZE+4:], p.ack)
|
|
buf[_TH_SIZE+8] = p.flag
|
|
buf[_TH_SIZE+9] = p.scnt
|
|
return buf
|
|
}
|
|
|
|
func unmarshall(pk *packet, buf []byte) {
|
|
if len(buf) >= _CH_SIZE {
|
|
pk.seq = binary.BigEndian.Uint32(buf)
|
|
pk.ack = binary.BigEndian.Uint32(buf[4:])
|
|
pk.flag = buf[8]
|
|
pk.scnt = buf[9]
|
|
pk.payload = buf[10:]
|
|
}
|
|
}
|
|
|
|
func (n *qNode) String() string {
|
|
now := Now()
|
|
return fmt.Sprintf("type=%s seq=%d scnt=%d sndtime~=%d,%d miss=%d",
|
|
packetTypeNames[n.flag], n.seq, n.scnt, n.sent-now, n.sent_1-now, n.miss)
|
|
}
|
|
|
|
func maxI64(a, b int64) int64 {
|
|
if a >= b {
|
|
return a
|
|
} else {
|
|
return b
|
|
}
|
|
}
|
|
|
|
func maxU32(a, b uint32) uint32 {
|
|
if a >= b {
|
|
return a
|
|
} else {
|
|
return b
|
|
}
|
|
}
|
|
|
|
func minI64(a, b int64) int64 {
|
|
if a <= b {
|
|
return a
|
|
} else {
|
|
return b
|
|
}
|
|
}
|
|
|
|
func maxI32(a, b int32) int32 {
|
|
if a >= b {
|
|
return a
|
|
} else {
|
|
return b
|
|
}
|
|
}
|
|
|
|
func minI32(a, b int32) int32 {
|
|
if a <= b {
|
|
return a
|
|
} else {
|
|
return b
|
|
}
|
|
}
|