Arremi/backend/midiDevice_linux.go
2018-03-20 10:08:53 +08:00

54 lines
1020 B
Go

package backend
import (
alsa "github.com/tonychee7000/Arremi/backend/alsa_wrapper"
"github.com/tonychee7000/Arremi/consts"
)
// MIDIDevice implies a Writer interface.
type MIDIDevice struct {
Signal chan int
}
// NewMIDIDevice construction func
func NewMIDIDevice() (*MIDIDevice, error) {
var mididev = new(MIDIDevice)
err := mididev.Init()
return mididev, err
}
// Init the client and source
func (midiDev *MIDIDevice) Init() error {
var err error
midiDev.Signal = make(chan int, 4096)
err = alsa.NewClient(consts.ClientName)
if err != nil {
return err
}
err = alsa.NewPort(consts.SourceName)
if err != nil {
return err
}
return nil
}
func (midiDev *MIDIDevice) Write(p []byte) (int, error) {
midiDev.Signal <- 1
err := alsa.SendData(p)
if err != nil {
return 0, err
}
return len(p), nil
}
// AllNoteOff I don't want panic!
func (midiDev *MIDIDevice) AllNoteOff() {
for i := 0; i < 16; i++ {
for j := 0; j < 128; j++ {
midiDev.Write([]byte{byte(0x90 + i), byte(j), 0})
}
}
}