mirror of https://bitbucket.org/ausocean/av.git
44 lines
757 B
Go
44 lines
757 B
Go
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package psi
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import (
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"encoding/binary"
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"errors"
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)
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func TimeToBytes(time uint64) []byte {
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s := make([]byte, 8)
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binary.BigEndian.PutUint64(s, time)
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return s
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}
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func chkTime(d []byte) error {
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if d[descTagIndx] != timeDescTag {
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return errors.New("PSI does not contain a time descriptor, cannot update")
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}
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return nil
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}
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// Updatetime
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func UpdateTime(d []byte, t int) error {
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err := chkTime(d)
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if err != nil {
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return err
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}
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ts := TimeToBytes(uint64(t))
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for i := range d[timeIndx : timeIndx+8] {
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d[i+timeIndx] = ts[i]
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}
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return nil
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}
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func TimeOf(d []byte) (t uint64, err error) {
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err = chkTime(d)
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if err != nil {
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return 0, err
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}
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for i := range d[timeIndx : timeIndx+8] {
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t |= uint64(d[i+timeIndx]) << uint(56-i*8)
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}
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return t, nil
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}
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