add beep function

beep_darwin.go

@@ -0,0 +1,28 @@
+// +build darwin
+
+package staros
+
+import (
+	"os"
+	"os/exec"
+)
+
+var (
+	// DefaultFreq - frequency, in Hz, middle A
+	DefaultFreq = 0.0
+	// DefaultDuration - duration in milliseconds
+	DefaultDuration = 0
+)
+
+// Beep beeps the PC speaker (https://en.wikipedia.org/wiki/PC_speaker).
+func Beep(freq float64, duration int) error {
+	osa, err := exec.LookPath("osascript")
+	if err != nil {
+		// Output the only beep we can
+		_, err = os.Stdout.Write([]byte{7})
+		return err
+	}
+
+	cmd := exec.Command(osa, "-e", `beep`)
+	return cmd.Run()
+}

beep_linux.go

@@ -0,0 +1,138 @@
+// +build linux
+
+package staros
+
+import (
+	"errors"
+	"os"
+	"syscall"
+	"time"
+	"unsafe"
+)
+
+// Constants
+const (
+	// This number represents the fixed frequency of the original PC XT's timer chip, which is approximately 1.193 MHz. This number
+	// is divided with the desired frequency to obtain a counter value, that is subsequently fed into the timer chip, tied to the PC speaker.
+	clockTickRate = 1193180
+
+	// linux/kd.h, start sound generation (0 for off)
+	kiocsound = 0x4B2F
+
+	// linux/input-event-codes.h
+	evSnd   = 0x12 // Event type
+	sndTone = 0x02 // Sound
+)
+
+var (
+	// DefaultFreq - frequency, in Hz, middle A
+	DefaultFreq = 440.0
+	// DefaultDuration - duration in milliseconds
+	DefaultDuration = 200
+)
+
+// inputEvent represents linux/input.h event structure.
+type inputEvent struct {
+	Time  syscall.Timeval // time in seconds since epoch at which event occurred
+	Type  uint16          // event type
+	Code  uint16          // event code related to the event type
+	Value int32           // event value related to the event type
+}
+
+// ioctl system call manipulates the underlying device parameters of special files.
+func ioctl(fd, name, data uintptr) error {
+	_, _, e := syscall.Syscall(syscall.SYS_IOCTL, fd, name, data)
+	if e != 0 {
+		return e
+	}
+
+	return nil
+}
+
+// Beep beeps the PC speaker (https://en.wikipedia.org/wiki/PC_speaker).
+//
+// On Linux it needs permission to access `/dev/tty0` or `/dev/input/by-path/platform-pcspkr-event-spkr` files for writing,
+// and `pcspkr` module must be loaded. User must be in correct groups, usually `input` and/or `tty`.
+//
+// If it can not open device files, it will fallback to sending Bell character (https://en.wikipedia.org/wiki/Bell_character).
+// For bell character in X11 terminals you can enable bell with `xset b on`. For console check `setterm` and `--blength` or `--bfreq` options.
+//
+// On macOS this just sends bell character. Enable `Audible bell` in Terminal --> Preferences --> Settings --> Advanced.
+//
+// On Windows it uses Beep function via syscall.
+//
+// On Web it plays hard coded beep sound.
+func Beep(freq float64, duration int) error {
+	if freq == 0 {
+		freq = DefaultFreq
+	} else if freq > 20000 {
+		freq = 20000
+	} else if freq < 0 {
+		freq = DefaultFreq
+	}
+
+	if duration == 0 {
+		duration = DefaultDuration
+	}
+
+	period := int(float64(clockTickRate) / freq)
+
+	var evdev bool
+
+	f, err := os.OpenFile("/dev/tty0", os.O_WRONLY, 0644)
+	if err != nil {
+		e := err
+		f, err = os.OpenFile("/dev/input/by-path/platform-pcspkr-event-spkr", os.O_WRONLY, 0644)
+		if err != nil {
+			e = errors.New("beeep: " + e.Error() + "; " + err.Error())
+
+			// Output the only beep we can
+			_, err = os.Stdout.Write([]byte{7})
+			if err != nil {
+				return errors.New(e.Error() + "; " + err.Error())
+			}
+
+			return nil
+		}
+
+		evdev = true
+	}
+
+	defer f.Close()
+
+	if evdev { // Use Linux evdev API
+		ev := inputEvent{}
+		ev.Type = evSnd
+		ev.Code = sndTone
+		ev.Value = int32(freq)
+
+		d := *(*[unsafe.Sizeof(ev)]byte)(unsafe.Pointer(&ev))
+
+		// Start beep
+		f.Write(d[:])
+
+		time.Sleep(time.Duration(duration) * time.Millisecond)
+
+		ev.Value = 0
+		d = *(*[unsafe.Sizeof(ev)]byte)(unsafe.Pointer(&ev))
+
+		// Stop beep
+		f.Write(d[:])
+	} else { // Use ioctl
+		// Start beep
+		err = ioctl(f.Fd(), kiocsound, uintptr(period))
+		if err != nil {
+			return err
+		}
+
+		time.Sleep(time.Duration(duration) * time.Millisecond)
+
+		// Stop beep
+		err = ioctl(f.Fd(), kiocsound, uintptr(0))
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

beep_test.go

@@ -0,0 +1,37 @@
+package staros
+
+import (
+	"fmt"
+	"testing"
+	"time"
+)
+
+const (
+	rat float64 = 1.059463094 //2^(1/12)
+	C   float64 = 493.8833013 * rat
+	CU          = C * rat * rat
+	D           = CU * rat
+	DU          = D * rat
+	E           = DU * rat
+	F           = E * rat
+	FU          = F * rat
+	G           = FU * rat
+	GU          = G * rat
+	A           = GU * rat
+	AU          = A * rat
+	B           = AU * rat
+)
+
+func beepMusic(qual ...float64) {
+	for _, v := range qual {
+		fmt.Println(v)
+		Beep(v, 700)
+		time.Sleep(time.Millisecond * 1000)
+	}
+}
+
+func Test_Music(t *testing.T) {
+	beepMusic(G, D, A, AU, A, G, F, D, DU, D, C, D, AU/2, C, G/2, C, D)
+	time.Sleep(time.Second * 3)
+	beepMusic(D,AU,A,G,A,D*2,F*2,G*2,F*2,D*2,D*2,C*2,D*2,DU*2,D*2,AU,A,E,G,FU)
+}

beep_windows.go

@@ -0,0 +1,41 @@
+// +build windows
+
+package staros
+
+import (
+	"syscall"
+)
+
+var (
+	// DefaultFreq - frequency, in Hz, middle A
+	DefaultFreq = 587.0
+	// DefaultDuration - duration in milliseconds
+	DefaultDuration = 500
+)
+
+// Beep beeps the PC speaker (https://en.wikipedia.org/wiki/PC_speaker).
+func Beep(freq float64, duration int) error {
+	if freq == 0 {
+		freq = DefaultFreq
+	} else if freq > 32767 {
+		freq = 32767
+	} else if freq < 37 {
+		freq = DefaultFreq
+	}
+
+	if duration == 0 {
+		duration = DefaultDuration
+	}
+
+	kernel32, _ := syscall.LoadLibrary("kernel32.dll")
+	beep32, _ := syscall.GetProcAddress(kernel32, "Beep")
+
+	defer syscall.FreeLibrary(kernel32)
+
+	_, _, e := syscall.Syscall(uintptr(beep32), uintptr(2), uintptr(int(freq)), uintptr(duration), 0)
+	if e != 0 {
+		return e
+	}
+
+	return nil
+}