37 lines
666 B
Go
37 lines
666 B
Go
package chunk
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const (
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chunkFlagVital = 1
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chunkFlagResend = 2
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)
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type ChunkFlags struct {
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Vital bool
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Resend bool
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}
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type ChunkHeader struct {
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Flags ChunkFlags
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Size int
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// sequence number
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// will be acknowledged in the packet header ack
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Seq int
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}
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type Chunk struct {
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Header ChunkHeader
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Data []byte
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}
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func (header *ChunkHeader) Unpack(data []byte) {
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flagBits := (data[0] >> 6) & 0x03
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header.Flags.Vital = (flagBits & chunkFlagVital) != 0
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header.Flags.Resend = (flagBits & chunkFlagResend) != 0
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header.Size = (int(data[0] & 0x3F) << 6) | (int(data[1]) & 0x3F)
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if header.Flags.Vital {
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header.Seq = int((data[1] & 0xC0) << 2) | int(data[2])
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}
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}
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