39 lines
796 B
Go
39 lines
796 B
Go
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package aep
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import "fmt"
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type Function uint8
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const (
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EchoRequest Function = 1
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EchoReply Function = 2
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)
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// Packet represents an AEP packet.
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type Packet struct {
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Function Function
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Data []byte
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}
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// Marshal marshals an AEP packet.
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func (p *Packet) Marshal() ([]byte, error) {
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if p.Function < 1 || p.Function > 2 {
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return nil, fmt.Errorf("invalid AEP function %d", p.Function)
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}
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if len(p.Data) == 0 {
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return nil, fmt.Errorf("empty AEP packet")
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}
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return append([]byte{byte(p.Function)}, p.Data...), nil
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}
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// Unmarshal unmarshals an AEP packet.
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func Unmarshal(data []byte) (*Packet, error) {
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if len(data) < 1 {
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return nil, fmt.Errorf("insufficient input length %d for AEP packet", len(data))
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}
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return &Packet{
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Function: Function(data[0]),
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Data: data[1:],
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}, nil
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}
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