57 lines
1.1 KiB
Go
57 lines
1.1 KiB
Go
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package packet
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const (
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packetFlagControl = 1
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packetFlagResend = 2
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packetFlagCompression = 4
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packetFlagConnless = 8
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)
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type PacketFlags struct {
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Connless bool
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Compression bool
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Resend bool
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Control bool
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}
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type PacketHeader struct {
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Flags PacketFlags
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Ack int
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NumChunks int
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Token [4]byte
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}
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func (header *PacketHeader) Unpack(packet []byte) {
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header.Flags.Unpack(packet)
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header.Ack = (int(packet[0]&0x3) << 8) | int(packet[1])
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header.NumChunks = int(packet[2])
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copy(header.Token[:], packet[3:7])
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}
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func (flags *PacketFlags) Unpack(packetHeaderRaw []byte) {
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flagBits := packetHeaderRaw[0] >> 2
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flags.Control = (flagBits & packetFlagControl) != 0
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flags.Resend = (flagBits & packetFlagResend) != 0
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flags.Compression = (flagBits & packetFlagCompression) != 0
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flags.Connless = (flagBits & packetFlagConnless) != 0
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}
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func (flags *PacketFlags) Pack() []byte {
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data := 0
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if flags.Control {
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data |= packetFlagControl
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}
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if flags.Resend {
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data |= packetFlagResend
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}
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if flags.Compression {
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data |= packetFlagCompression
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}
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if flags.Connless {
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data |= packetFlagConnless
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}
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return []byte{byte(data)}
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}
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