fga-eps-mds/2019.1-unbrake

package main

import (
    "github.com/tarm/serial"
    "log"
    "sync"
    "time"
)

// Port represents the serial inteface with the connected device
type Port struct {
    port     *serial.Port
    readMux  sync.Mutex
    writeMux sync.Mutex
}

// Write in the serial port
func (port *Port) Write(data []byte) int {
    var n int
    var err error

    port.writeMux.Lock()
    defer port.writeMux.Unlock()

    if port.port != nil {
        n, err = port.port.Write(data)
        if err != nil {
            log.Printf("Could not to write on port: %v", err)
            n = -1
        }
    } else {
        log.Println("Was tried to write in a nil port")
        n = -1
    }
    return n
}

// Read from the serial port
func (port *Port) Read(data []byte) (int, error) {

    port.readMux.Lock()
    defer port.readMux.Unlock()

    var err error
    var n int

    if port.port != nil {
        n, err = port.port.Read(data)
        if err != nil {
            log.Printf("Was not possible to read from serial port: %v", err)
        }
    } else {
        log.Println("Was tried te read from a nil port")
    }

    return n, err

}

// Open a new serial port
func (port *Port) Open(portName string) error {

    port.readMux.Lock()
    port.writeMux.Lock()
    defer port.readMux.Unlock()
    defer port.writeMux.Unlock()

    var err error

    configuration := &serial.Config{
        Name:        portName,
        Baud:        baudRate,
        ReadTimeout: time.Second,
    }

    port.port, err = serial.OpenPort(configuration)

    if err != nil {
        log.Printf("Was not possible to open the serial port: %v", err)
    }

    return err
}

// IsOpen return true if the port is open
func (port *Port) IsOpen() bool {
    return port.port != nil
}

// Flush to clean the buffer
func (port *Port) Flush() {
    port.port.Flush()
}

// Close the serial port
func (port *Port) Close() {
    port.port.Close()
}