all: change DefaultAdapter function to global

All initialization can be done in the Enable call. This makes the API a bit simpler and a bit more consistent between Nordic chips and other BLE interfaces.
tinygo-org · Jun 1, 2020 · 0474d7b · 0474d7b
1 parent d9d4255
commit 0474d7b
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Showing 9 changed files with 41 additions and 53 deletions.
diff --git a/adapter_linux.go b/adapter_linux.go
@@ -14,27 +14,21 @@ type Adapter struct {
 	cancelScan func()
 }
 
-// DefaultAdapter returns the default adapter on the current system. On Linux,
-// it will return the first adapter available.
-func DefaultAdapter() (*Adapter, error) {
-	adapter, err := api.GetDefaultAdapter()
-	if err != nil {
-		return nil, err
-	}
-	adapterID, err := adapter.GetAdapterID()
-	if err != nil {
-		return nil, err
-	}
-	return &Adapter{
-		adapter: adapter,
-		id:      adapterID,
-	}, nil
-}
+// DefaultAdapter is the default adapter on the system. On Linux, it is the
+// first adapter available.
+//
+// Make sure to call Enable() before using it to initialize the adapter.
+var DefaultAdapter = &Adapter{}
 
 // Enable configures the BLE stack. It must be called before any
 // Bluetooth-related calls (unless otherwise indicated).
-//
-// The Linux implementation is a no-op.
-func (a *Adapter) Enable() error {
+func (a *Adapter) Enable() (err error) {
+	if a.id == "" {
+		a.adapter, err = api.GetDefaultAdapter()
+		if err != nil {
+			return
+		}
+		a.id, err = a.adapter.GetAdapterID()
+	}
 	return nil
 }
diff --git a/adapter_nrf51.go b/adapter_nrf51.go
@@ -46,12 +46,12 @@ func handleEvent() {
 		gapEvent := eventBuf.evt.unionfield_gap_evt()
 		switch id {
 		case C.BLE_GAP_EVT_CONNECTED:
-			handler := defaultAdapter.handler
+			handler := DefaultAdapter.handler
 			if handler != nil {
 				handler(&ConnectEvent{GAPEvent: GAPEvent{Connection(gapEvent.conn_handle)}})
 			}
 		case C.BLE_GAP_EVT_DISCONNECTED:
-			handler := defaultAdapter.handler
+			handler := DefaultAdapter.handler
 			if handler != nil {
 				handler(&DisconnectEvent{GAPEvent: GAPEvent{Connection(gapEvent.conn_handle)}})
 			}
@@ -76,7 +76,7 @@ func handleEvent() {
 			writeEvent := gattsEvent.params.unionfield_write()
 			len := writeEvent.len - writeEvent.offset
 			data := (*[255]byte)(unsafe.Pointer(&writeEvent.data[0]))[:len:len]
-			handler := defaultAdapter.getCharWriteHandler(writeEvent.handle)
+			handler := DefaultAdapter.getCharWriteHandler(writeEvent.handle)
 			if handler != nil {
 				handler.callback(Connection(gattsEvent.conn_handle), int(writeEvent.offset), data)
 			}

diff --git a/adapter_nrf528xx.go b/adapter_nrf528xx.go
@@ -49,12 +49,12 @@ func handleEvent() {
 		gapEvent := eventBuf.evt.unionfield_gap_evt()
 		switch id {
 		case C.BLE_GAP_EVT_CONNECTED:
-			handler := defaultAdapter.handler
+			handler := DefaultAdapter.handler
 			if handler != nil {
 				handler(&ConnectEvent{GAPEvent: GAPEvent{Connection(gapEvent.conn_handle)}})
 			}
 		case C.BLE_GAP_EVT_DISCONNECTED:
-			handler := defaultAdapter.handler
+			handler := DefaultAdapter.handler
 			if handler != nil {
 				handler(&DisconnectEvent{GAPEvent: GAPEvent{Connection(gapEvent.conn_handle)}})
 			}
@@ -99,7 +99,7 @@ func handleEvent() {
 			writeEvent := gattsEvent.params.unionfield_write()
 			len := writeEvent.len - writeEvent.offset
 			data := (*[255]byte)(unsafe.Pointer(&writeEvent.data[0]))[:len:len]
-			handler := defaultAdapter.getCharWriteHandler(writeEvent.handle)
+			handler := DefaultAdapter.getCharWriteHandler(writeEvent.handle)
 			if handler != nil {
 				handler.callback(Connection(gattsEvent.conn_handle), int(writeEvent.offset), data)
 			}

diff --git a/adapter_sd.go b/adapter_sd.go
@@ -38,15 +38,11 @@ type Adapter struct {
 	charWriteHandlers []charWriteHandler
 }
 
-// defaultAdapter is an adapter to the default Bluetooth stack on a given
-// target.
-var defaultAdapter = Adapter{isDefault: true}
-
-// DefaultAdapter returns the default adapter on the current system. On Nordic
-// chips, it will return the SoftDevice interface.
-func DefaultAdapter() (*Adapter, error) {
-	return &defaultAdapter, nil
-}
+// DefaultAdapter is the default adapter on the current system. On Nordic chips,
+// it will return the SoftDevice interface.
+//
+// Make sure to call Enable() before using it to initialize the adapter.
+var DefaultAdapter = Adapter{isDefault: true}
 
 // Enable configures the BLE stack. It must be called before any
 // Bluetooth-related calls (unless otherwise indicated).

diff --git a/adapter_windows.go b/adapter_windows.go
@@ -10,12 +10,10 @@ type Adapter struct {
 	watcher *winbt.IBluetoothLEAdvertisementWatcher
 }
 
-var defaultAdapter Adapter
-
-// DefaultAdapter returns the default adapter on the current system.
-func DefaultAdapter() (*Adapter, error) {
-	return &defaultAdapter, nil
-}
+// DefaultAdapter is the default adapter on the system.
+//
+// Make sure to call Enable() before using it to initialize the adapter.
+var DefaultAdapter = Adapter{}
 
 // Enable configures the BLE stack. It must be called before any
 // Bluetooth-related calls (unless otherwise indicated).

diff --git a/examples/advertisement/main.go b/examples/advertisement/main.go
@@ -9,10 +9,10 @@ import (
 // flags + local name
 var advPayload = []byte("\x02\x01\x06" + "\x07\x09TinyGo")
 
+var adapter = bluetooth.DefaultAdapter
+
 func main() {
-	adapter, err := bluetooth.DefaultAdapter()
-	must("get default adapter", err)
-	must("enable SD", adapter.Enable())
+	must("enable BLE stack", adapter.Enable())
 	adv := adapter.NewAdvertisement()
 	options := &bluetooth.AdvertiseOptions{
 		Interval: bluetooth.NewAdvertiseInterval(100),

diff --git a/examples/heartrate/main.go b/examples/heartrate/main.go
@@ -9,15 +9,15 @@ import (
 // flags + local name
 var advPayload = []byte("\x02\x01\x06" + "\x07\x09TinyGo")
 
+var adapter = bluetooth.DefaultAdapter
+
 // TODO: use atomics to access this value.
 var heartRate uint8 = 75 // 75bpm
 
 func main() {
 	println("starting")
-	adapter, err := bluetooth.DefaultAdapter()
-	must("get default adapter", err)
 	adapter.SetEventHandler(handleBluetoothEvents)
-	must("enable SD", adapter.Enable())
+	must("enable BLE stack", adapter.Enable())
 	adv := adapter.NewAdvertisement()
 	options := &bluetooth.AdvertiseOptions{
 		Interval: bluetooth.NewAdvertiseInterval(100),

diff --git a/examples/ledcolor/main.go b/examples/ledcolor/main.go
@@ -10,6 +10,8 @@ import (
 // flags + local name
 var advPayload = []byte("\x02\x01\x06" + "\x0b\x09LED colors")
 
+var adapter = bluetooth.DefaultAdapter
+
 // TODO: use atomics to access this value.
 var ledColor = [3]byte{0xff, 0x00, 0x00} // start out with red
 var leds = [3]machine.Pin{machine.LED_RED, machine.LED_GREEN, machine.LED_BLUE}
@@ -22,10 +24,8 @@ var (
 
 func main() {
 	println("starting")
-	adapter, err := bluetooth.DefaultAdapter()
-	must("get default adapter", err)
 	adapter.SetEventHandler(handleBluetoothEvents)
-	must("enable SD", adapter.Enable())
+	must("enable BLE stack", adapter.Enable())
 	adv := adapter.NewAdvertisement()
 	options := &bluetooth.AdvertiseOptions{
 		Interval: bluetooth.NewAdvertiseInterval(100),

diff --git a/examples/scanner/main.go b/examples/scanner/main.go
@@ -4,15 +4,15 @@ import (
 	"github.com/tinygo-org/bluetooth"
 )
 
+var adapter = bluetooth.DefaultAdapter
+
 func main() {
 	// Enable BLE interface.
-	adapter, err := bluetooth.DefaultAdapter()
-	must("get default adapter", err)
-	must("enable adapter", adapter.Enable())
+	must("enable BLE stack", adapter.Enable())
 
 	// Start scanning.
 	println("scanning...")
-	err = adapter.Scan(func(adapter *bluetooth.Adapter, device bluetooth.ScanResult) {
+	err := adapter.Scan(func(adapter *bluetooth.Adapter, device bluetooth.ScanResult) {
 		println("found device:", device.Address.String(), device.RSSI, device.LocalName())
 	})
 	must("start scan", err)