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package dhcpv4
import (
"fmt"
)
// This option implements the TFTP server name option.
// https://tools.ietf.org/html/rfc2132
// OptTFTPServerName implements the TFTP server name option.
type OptTFTPServerName struct {
TFTPServerName []byte
}
// Code returns the option code
func (op *OptTFTPServerName) Code() OptionCode {
return OptionTFTPServerName
}
// ToBytes serializes the option and returns it as a sequence of bytes
func (op *OptTFTPServerName) ToBytes() []byte {
return append([]byte{byte(op.Code()), byte(op.Length())}, op.TFTPServerName...)
}
// Length returns the option length in bytes
func (op *OptTFTPServerName) Length() int {
return len(op.TFTPServerName)
}
func (op *OptTFTPServerName) String() string {
return fmt.Sprintf("TFTP Server Name -> %s", op.TFTPServerName)
}
// ParseOptTFTPServerName returns a new OptTFTPServerName fomr a byte stream or error if any
func ParseOptTFTPServerName(data []byte) (*OptTFTPServerName, error) {
if len(data) < 3 {
return nil, ErrShortByteStream
}
code := OptionCode(data[0])
if code != OptionTFTPServerName {
return nil, fmt.Errorf("ParseOptTFTPServerName: invalid code: %v; want %v",
code, OptionTFTPServerName)
}
length := int(data[1])
if length < 1 {
return nil, fmt.Errorf("TFTP server name has invalid length of %d", length)
}
TFTPServerNameData := data[2:]
if len(TFTPServerNameData) < length {
return nil, fmt.Errorf("ParseOptTFTPServerName: short data: %d bytes; want %d",
len(TFTPServerNameData), length)
}
return &OptTFTPServerName{TFTPServerName: TFTPServerNameData[:length]}, nil
}
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