44 lines
1 KiB
Go
44 lines
1 KiB
Go
package shared
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import (
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"fmt"
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log "github.com/sirupsen/logrus"
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"io"
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"time"
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)
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// receive at maximum the requested number of bytes from serial port and stop after the given timeout
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func ReceiveBytes(port *io.ReadWriteCloser, count int, timeout time.Duration) ([]byte, error) {
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readCh := make(chan []byte, 1)
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errCh := make(chan error, 1)
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go func() {
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data := make([]byte, count)
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if readBytes, err := (*port).Read(data); err != nil {
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errCh <- err
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} else if readBytes > 0 {
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log.Tracef("%d bytes read", readBytes)
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readCh <- data[0:readBytes]
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} else {
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readCh <- make([]byte, 0)
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}
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return
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}()
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select {
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case <-time.After(timeout):
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return nil, fmt.Errorf("timeout passed %v: %v", timeout)
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case err := <-errCh:
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return nil, err
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case data := <-readCh:
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return data, nil
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}
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}
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func SendByte(port *io.ReadWriteCloser, data byte) error {
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if bytesWritten, err := (*port).Write([]byte{data}); err != nil {
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return err
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} else {
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log.Tracef("wrote %d bytes of handshake info", bytesWritten)
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}
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return nil
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}
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