added semaphores around disconnect and reconnect to prevent crash due…

… to double (dis)connect

dbus.go

@@ -43,7 +43,7 @@ func (StreamDeckDBus) ReloadConfig() *dbus.Error {
 }
 
 func (StreamDeckDBus) SetPage(page int) *dbus.Error {
-	SetPage(config, page, dev)
+	SetPage(config, page)
 	return nil
 }
 

go.mod

@@ -10,4 +10,5 @@ require (
 	github.com/unix-streamdeck/api v0.0.0-20200818180846-6942d99617b2
 	github.com/unix-streamdeck/driver v0.0.0-20200817173808-cdaf123c076b
 	golang.org/x/image v0.0.0-20200119044424-58c23975cae1
+	golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4
 )

go.sum

@@ -115,6 +115,7 @@ golang.org/x/net v0.0.0-20190522155817-f3200d17e092/go.mod h1:HSz+uSET+XFnRR8LxR
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4 h1:YUO/7uOKsKeq9UokNS62b8FYywz3ker1l1vDZRCRefw=
 golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=

interface.go

@@ -35,15 +35,12 @@ func ResizeImage(img image.Image) image.Image {
 	return resize.Resize(dev.Pixels, dev.Pixels, img, resize.Lanczos3)
 }
 
-func SetImage(img image.Image, i int, page int, dev streamdeck.Device) {
+func SetImage(img image.Image, i int, page int, _ streamdeck.Device) {
 	if p == page && isOpen {
 		err := dev.SetImage(uint8(i), img)
 		if err != nil {
 			if strings.Contains(err.Error(), "hidapi") {
-				log.Println("Device disconnected")
-				_ = dev.Close()
-				isOpen = false
-				unmountHandlers()
+				disconnect()
 			} else {
 				log.Println(err)
 			}
@@ -79,7 +76,7 @@ func SetKey(currentKey *api.Key, i int) {
 	}
 }
 
-func SetPage(config *api.Config, page int, dev streamdeck.Device) {
+func SetPage(config *api.Config, page int) {
 	p = page
 	currentPage := config.Pages[page]
 	for i := 0; i < len(currentPage); i++ {
@@ -100,7 +97,7 @@ func SetPage(config *api.Config, page int, dev streamdeck.Device) {
 				if handler == nil {
 					continue
 				}
-				handler.Icon(page, i, currentKey, dev)
+				handler.Icon(page, i, currentKey, streamdeck.Device{})
 				currentKey.IconHandlerStruct = handler
 			}
 		} else {
@@ -110,7 +107,7 @@ func SetPage(config *api.Config, page int, dev streamdeck.Device) {
 	EmitPage(p)
 }
 
-func HandleInput(key *api.Key, page int, index int, dev streamdeck.Device) {
+func HandleInput(key *api.Key, page int, index int) {
 	if key.Command != "" {
 		runCommand(key.Command)
 	}
@@ -119,7 +116,7 @@ func HandleInput(key *api.Key, page int, index int, dev streamdeck.Device) {
 	}
 	if key.SwitchPage != 0 {
 		page = key.SwitchPage - 1
-		SetPage(config, page, dev)
+		SetPage(config, page)
 	}
 	if key.Brightness != 0 {
 		_ = dev.SetBrightness(uint8(key.Brightness))
@@ -138,7 +135,7 @@ func HandleInput(key *api.Key, page int, index int, dev streamdeck.Device) {
 			}
 			key.KeyHandlerStruct = handler
 		}
-		key.KeyHandlerStruct.Key(page, index, key, dev)
+		key.KeyHandlerStruct.Key(page, index, key, streamdeck.Device{})
 	}
 }
 
@@ -151,15 +148,12 @@ func Listen() {
 		select {
 		case k, ok := <-kch:
 			if !ok {
-				log.Println("Device disconnected")
-				_ = dev.Close()
-				isOpen = false
-				unmountHandlers()
-				continue
+				disconnect()
+				return
 			}
 			if k.Pressed == true {
 				if len(config.Pages)-1 >= p && len(config.Pages[p])-1 >= int(k.Index) {
-					HandleInput(&config.Pages[p][k.Index], p, int(k.Index), dev)
+					HandleInput(&config.Pages[p][k.Index], p, int(k.Index))
 				}
 			}
 		}

main.go

@@ -1,11 +1,13 @@
 package main
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"github.com/unix-streamdeck/api"
 	"github.com/unix-streamdeck/driver"
+	"golang.org/x/sync/semaphore"
 	_ "image/gif"
 	_ "image/jpeg"
 	_ "image/png"
@@ -21,6 +23,8 @@ var dev streamdeck.Device
 var config *api.Config
 var configPath = os.Getenv("HOME") + string(os.PathSeparator) + ".streamdeck-config.json"
 var isOpen = false
+var disconnectSem = semaphore.NewWeighted(1)
+var connectSem = semaphore.NewWeighted(1)
 
 var basicConfig = api.Config{
 	Pages: []api.Page{
@@ -59,38 +63,58 @@ func main() {
 }
 
 func attemptConnection() {
-	for {
-		if !isOpen {
-			_ = openDevice()
-			if isOpen {
-				go Listen()
-				SetPage(config, p, dev)
-				if sDbus != nil {
-					sDbus.IconSize = int(dev.Pixels)
-					sDbus.Rows = int(dev.Rows)
-					sDbus.Cols = int(dev.Columns)
-				}
+	for !isOpen {
+		_ = openDevice()
+		if isOpen {
+			SetPage(config, p)
+			if sDbus != nil {
+				sDbus.IconSize = int(dev.Pixels)
+				sDbus.Rows = int(dev.Rows)
+				sDbus.Cols = int(dev.Columns)
 			}
+			Listen()
 		}
 	}
 }
 
+func disconnect() {
+	ctx := context.Background()
+	err := disconnectSem.Acquire(ctx, 1)
+	if err != nil {
+		return
+	}
+	defer disconnectSem.Release(1)
+	if !isOpen {
+		return
+	}
+	log.Println("Device disconnected")
+	_ = dev.Close()
+	isOpen = false
+	unmountHandlers()
+}
+
 func openDevice() error {
+	ctx := context.Background()
+	err := connectSem.Acquire(ctx, 1)
+	if err != nil {
+		return err
+	}
+	defer connectSem.Release(1)
 	d, err := streamdeck.Devices()
 	if err != nil {
 		return err
 	}
 	if len(d) == 0 {
 		return errors.New("No streamdeck devices found")
 	}
-	dev = d[0]
-	err = dev.Open()
+	err = d[0].Open()
 	if err != nil {
 		return err
 	}
+	dev = d[0]
 	isOpen = true
 	fmt.Println("Device (" + dev.Serial + ") connected")
-	return err
+	return nil
 }
 
 func readConfig() (*api.Config, error) {
@@ -139,7 +163,7 @@ func SetConfig(configString string) error {
 	if len(config.Pages) == 0 {
 		config.Pages = append(config.Pages, api.Page{})
 	}
-	SetPage(config, p, dev)
+	SetPage(config, p)
 	return nil
 }
 
@@ -153,7 +177,7 @@ func ReloadConfig() error {
 	if len(config.Pages) == 0 {
 		config.Pages = append(config.Pages, api.Page{})
 	}
-	SetPage(config, p, dev)
+	SetPage(config, p)
 	return nil
 }