changes to error handling

readme, changelog updated to reflect changes

version bump

CHANGELOG.md

@@ -11,6 +11,14 @@ Before any major/minor/patch bump all unit tests will be run to verify they pass
 
 -   [x]
 
+## [1.4.0] - 2022-09-07
+
+### Changed
+
+-   changes to error handling.
+    -   functions that wrap capi calls now return error types.
+    -   higher level functions print error messages
+
 ## [1.3.0] - 2022-08-22
 
 ### Added

README.md

@@ -53,9 +53,12 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	defer vm.Logout()
 
-	vm.Login()
+	err = vm.Login()
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer vm.Logout()
 
 	vm.Strip[0].SetLabel("rode podmic")
 	vm.Strip[0].SetMute(true)

base.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"fmt"
 	"math"
-	"os"
 	"strings"
 	"syscall"
 	"time"
@@ -44,36 +43,36 @@ var (
 // login logs into the API,
 // attempts to launch Voicemeeter if it's not running,
 // initializes dirty parameters.
-func login(kindId string) {
+func login(kindId string) error {
 	res, _, _ := vmLogin.Call()
 	if res == 1 {
 		runVoicemeeter(kindId)
 		time.Sleep(time.Second)
 	} else if res != 0 {
 		err := fmt.Errorf("VBVMR_Login returned %d", res)
-		fmt.Println(err)
+		return err
-		os.Exit(1)
 	}
 	fmt.Printf("Logged into Voicemeeter %s\n", kindId)
 	for pdirty() || mdirty() {
 	}
+	return nil
 }
 
 // logout logs out of the API,
 // delayed for 100ms to allow final operation to complete.
-func logout(kindId string) {
+func logout(kindId string) error {
 	time.Sleep(100 * time.Millisecond)
 	res, _, _ := vmLogout.Call()
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_Logout returned %d", res)
-		fmt.Println(err)
+		return err
-		os.Exit(1)
 	}
 	fmt.Printf("Logged out of Voicemeeter %s\n", kindId)
+	return nil
 }
 
 // runVoicemeeter attempts to launch a Voicemeeter GUI of a kind.
-func runVoicemeeter(kindId string) {
+func runVoicemeeter(kindId string) error {
 	vals := map[string]uint64{
 		"basic":  1,
 		"banana": 2,
@@ -82,25 +81,24 @@ func runVoicemeeter(kindId string) {
 	res, _, _ := vmRunvm.Call(uintptr(vals[kindId]))
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_RunVoicemeeter returned %d", res)
-		fmt.Println(err)
+		return err
-		os.Exit(1)
 	}
+	return nil
 }
 
 // getVersion returns the version of Voicemeeter as a string
-func getVersion() string {
+func getVersion() (string, error) {
 	var ver uint64
 	res, _, _ := vmGetvmVersion.Call(uintptr(unsafe.Pointer(&ver)))
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_GetVoicemeeterVersion returned %d", res)
-		fmt.Println(err)
+		return "", err
-		os.Exit(1)
 	}
 	v1 := (ver & 0xFF000000) >> 24
 	v2 := (ver & 0x00FF0000) >> 16
 	v3 := (ver & 0x0000FF00) >> 8
 	v4 := ver & 0x000000FF
-	return fmt.Sprintf("%d.%d.%d.%d", v1, v2, v3, v4)
+	return fmt.Sprintf("%d.%d.%d.%d", v1, v2, v3, v4), nil
 }
 
 // pdirty returns true iff a parameter value has changed
@@ -121,37 +119,38 @@ func ldirty(k *kind) bool {
 	_levelCache.busLevelsBuff = make([]float32, 8*k.NumBus())
 
 	for i := 0; i < (2*k.PhysIn)+(8*k.VirtIn); i++ {
-		_levelCache.stripLevelsBuff[i] = float32(getLevel(_levelCache.stripMode, i))
+		val, _ := getLevel(_levelCache.stripMode, i)
+		_levelCache.stripLevelsBuff[i] = val
 		_levelCache.stripComp[i] = _levelCache.stripLevelsBuff[i] == _levelCache.stripLevels[i]
 	}
 	for i := 0; i < 8*k.NumBus(); i++ {
-		_levelCache.busLevelsBuff[i] = float32(getLevel(3, i))
+		val, _ := getLevel(3, i)
+		_levelCache.busLevelsBuff[i] = val
 		_levelCache.busComp[i] = _levelCache.busLevelsBuff[i] == _levelCache.busLevels[i]
 	}
 	return !(allTrue(_levelCache.stripComp, (2*k.PhysIn)+(8*k.VirtIn)) && allTrue(_levelCache.busComp, 8*k.NumBus()))
 }
 
 // getVMType returns the type of Voicemeeter, as a string
-func getVMType() string {
+func getVMType() (string, error) {
 	var type_ uint64
 	res, _, _ := vmGetvmType.Call(
 		uintptr(unsafe.Pointer(&type_)),
 	)
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_GetVoicemeeterType returned %d", res)
-		fmt.Println(err)
+		return "", err
-		os.Exit(1)
 	}
 	vals := map[uint64]string{
 		1: "basic",
 		2: "banana",
 		3: "potato",
 	}
-	return vals[type_]
+	return vals[type_], nil
 }
 
 // getParameterFloat gets the value of a float parameter
-func getParameterFloat(name string) float64 {
+func getParameterFloat(name string) (float64, error) {
 	var value float32
 	b := append([]byte(name), 0)
 	res, _, _ := vmGetParamFloat.Call(
@@ -160,14 +159,13 @@ func getParameterFloat(name string) float64 {
 	)
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_GetParameterFloat returned %d", res)
-		fmt.Println(err)
+		return 0, err
-		os.Exit(1)
 	}
-	return math.Round(float64(value)*10) / 10
+	return math.Round(float64(value)*10) / 10, nil
 }
 
 // setParameterFloat sets the value of a float parameter
-func setParameterFloat(name string, value float32) {
+func setParameterFloat(name string, value float32) error {
 	b1 := append([]byte(name), 0)
 	b2 := math.Float32bits(value)
 	res, _, _ := vmSetParamFloat.Call(
@@ -176,13 +174,13 @@ func setParameterFloat(name string, value float32) {
 	)
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_SetParameterFloat returned %d", res)
-		fmt.Println(err)
+		return err
-		os.Exit(1)
 	}
+	return nil
 }
 
 // getParameterString gets the value of a string parameter
-func getParameterString(name string) string {
+func getParameterString(name string) (string, error) {
 	b1 := append([]byte(name), 0)
 	var b2 [512]byte
 	res, _, _ := vmGetParamString.Call(
@@ -191,15 +189,14 @@ func getParameterString(name string) string {
 	)
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_GetParameterStringA returned %d", res)
-		fmt.Println(err)
+		return "", err
-		os.Exit(1)
 	}
 	str := bytes.Trim(b2[:], "\x00")
-	return string(str)
+	return string(str), nil
 }
 
-// getParameterString sets the value of a string parameter
+// setParameterString sets the value of a string parameter
-func setParameterString(name, value string) {
+func setParameterString(name, value string) error {
 	b1 := append([]byte(name), 0)
 	b2 := append([]byte(value), 0)
 	res, _, _ := vmSetParamString.Call(
@@ -208,26 +205,26 @@ func setParameterString(name, value string) {
 	)
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_SetParameterStringA returned %d", res)
-		fmt.Println(err)
+		return err
-		os.Exit(1)
 	}
+	return nil
 }
 
 // setParametersMulti sets multiple parameters with a script
-func setParametersMulti(script string) {
+func setParametersMulti(script string) error {
 	b1 := append([]byte(script), 0)
 	res, _, _ := vmSetParameters.Call(
 		uintptr(unsafe.Pointer(&b1[0])),
 	)
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_SetParameters returned %d", res)
-		fmt.Println(err)
+		return err
-		os.Exit(1)
 	}
+	return nil
 }
 
 // getMacroStatus gets a macrobutton value
-func getMacroStatus(id, mode int) float32 {
+func getMacroStatus(id, mode int) (float32, error) {
 	var state float32
 	res, _, _ := vmGetMacroStatus.Call(
 		uintptr(id),
@@ -236,14 +233,13 @@ func getMacroStatus(id, mode int) float32 {
 	)
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_MacroButton_GetStatus returned %d", res)
-		fmt.Println(err)
+		return 0, err
-		os.Exit(1)
 	}
-	return state
+	return state, nil
 }
 
 // setMacroStatus sets a macrobutton value
-func setMacroStatus(id, state, mode int) {
+func setMacroStatus(id, state, mode int) error {
 	res, _, _ := vmSetMacroStatus.Call(
 		uintptr(id),
 		uintptr(state),
@@ -251,9 +247,9 @@ func setMacroStatus(id, state, mode int) {
 	)
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_MacroButton_SetStatus returned %d", res)
-		fmt.Println(err)
+		return err
-		os.Exit(1)
 	}
+	return nil
 }
 
 // getNumDevices returns the number of hardware input/output devices
@@ -268,7 +264,7 @@ func getNumDevices(dir string) uint64 {
 }
 
 // getDeviceDescription returns name, driver type and hwid for a given device
-func getDeviceDescription(i int, dir string) (string, uint64, string) {
+func getDeviceDescription(i int, dir string) (string, uint64, string, error) {
 	var t_ uint64
 	var b1 [512]byte
 	var b2 [512]byte
@@ -281,8 +277,7 @@ func getDeviceDescription(i int, dir string) (string, uint64, string) {
 		)
 		if res != 0 {
 			err := fmt.Errorf("VBVMR_Input_GetDeviceDescA returned %d", res)
-			fmt.Println(err)
+			return "", 0, "", err
-			os.Exit(1)
 		}
 	} else {
 		res, _, _ := vmGetDevDescOut.Call(
@@ -293,17 +288,16 @@ func getDeviceDescription(i int, dir string) (string, uint64, string) {
 		)
 		if res != 0 {
 			err := fmt.Errorf("VBVMR_Output_GetDeviceDescA returned %d", res)
-			fmt.Println(err)
+			return "", 0, "", err
-			os.Exit(1)
 		}
 	}
 	name := bytes.Trim(b1[:], "\x00")
 	hwid := bytes.Trim(b2[:], "\x00")
-	return string(name), t_, string(hwid)
+	return string(name), t_, string(hwid), nil
 }
 
 // getLevel returns a single level value of type type_ for channel[i]
-func getLevel(type_, i int) float32 {
+func getLevel(type_, i int) (float32, error) {
 	var val float32
 	res, _, _ := vmGetLevelFloat.Call(
 		uintptr(type_),
@@ -312,10 +306,9 @@ func getLevel(type_, i int) float32 {
 	)
 	if res != 0 {
 		err := fmt.Errorf("VBVMR_GetLevel returned %d", res)
-		fmt.Println(err)
+		return 0, err
-		os.Exit(1)
 	}
-	return val
+	return val, nil
 }
 
 // getMidiMessage gets midi channel, pitch and velocity for a single midi input
@@ -329,8 +322,10 @@ func getMidiMessage() bool {
 	x := int(res)
 	if x < 0 {
 		err := fmt.Errorf("VBVMR_GetMidiMessage returned %d", res)
+		if err != nil {
 			fmt.Println(err)
-		os.Exit(1)
+		}
+		return false
 	}
 	msg := bytes.Trim(b1[:], "\x00")
 	if len(msg) > 0 {

button.go

@@ -14,7 +14,11 @@ func newButton(i int) button {
 
 // getter returns the value of a macrobutton parameter
 func (m *button) getter(mode int) bool {
-	return getMacroStatus(m.index, mode) == 1
+	val, err := getMacroStatus(m.index, mode)
+	if err != nil {
+		fmt.Println(err)
+	}
+	return val == 1
 }
 
 // setter sets the value of a macrobutton parameter

device.go

@@ -1,5 +1,7 @@
 package voicemeeter
 
+import "fmt"
+
 type devDesc struct {
 	Name, Type, Hwid string
 }
@@ -22,7 +24,10 @@ func (d *device) Outs() int {
 }
 
 func (d *device) Input(i int) devDesc {
-	n, t_, id := getDeviceDescription(i, "in")
+	n, t_, id, err := getDeviceDescription(i, "in")
+	if err != nil {
+		fmt.Println(err)
+	}
 	vals := map[uint64]string{
 		1: "mme",
 		3: "wdm",
@@ -33,7 +38,10 @@ func (d *device) Input(i int) devDesc {
 }
 
 func (d *device) Output(i int) devDesc {
-	n, t_, id := getDeviceDescription(i, "out")
+	n, t_, id, err := getDeviceDescription(i, "out")
+	if err != nil {
+		fmt.Println(err)
+	}
 	vals := map[uint64]string{
 		1: "mme",
 		3: "wdm",

examples/obs/main.go

@@ -43,9 +43,12 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	defer vm.Logout()
 
-	vm.Login()
+	err = vm.Login()
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer vm.Logout()
 
 	obs, err := goobs.New("localhost:4455", goobs.WithPassword("mystrongpass"))
 	if err != nil {

examples/observer/main.go

@@ -48,9 +48,12 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	defer vm.Logout()
 
-	vm.Login()
+	err = vm.Login()
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer vm.Logout()
 	// enable level updates (disabled by default)
 	vm.EventAdd("ldirty")
 

iremote.go

@@ -19,7 +19,11 @@ func (ir *iRemote) identifier() string {
 // getter_bool returns the value of a boolean parameter
 func (ir *iRemote) getter_bool(p string) bool {
 	param := fmt.Sprintf("%s.%s", ir.identifier(), p)
-	return getParameterFloat(param) == 1
+	val, err := getParameterFloat(param)
+	if err != nil {
+		fmt.Println(err)
+	}
+	return val == 1
 }
 
 // setter_bool sets the value of a boolean parameter
@@ -31,41 +35,65 @@ func (ir *iRemote) setter_bool(p string, v bool) {
 	} else {
 		value = 0
 	}
-	setParameterFloat(param, float32(value))
+	err := setParameterFloat(param, float32(value))
+	if err != nil {
+		fmt.Println(err)
+	}
 }
 
 // getter_int returns the value of an int parameter p
 func (ir *iRemote) getter_int(p string) int {
 	param := fmt.Sprintf("%s.%s", ir.identifier(), p)
-	return int(getParameterFloat(param))
+	val, err := getParameterFloat(param)
+	if err != nil {
+		fmt.Println(err)
+	}
+	return int(val)
 }
 
 // setter_int sets the value v of an int parameter p
 func (ir *iRemote) setter_int(p string, v int) {
 	param := fmt.Sprintf("%s.%s", ir.identifier(), p)
-	setParameterFloat(param, float32(v))
+	err := setParameterFloat(param, float32(v))
+	if err != nil {
+		fmt.Println(err)
+	}
 }
 
 // getter_float returns the value of an int parameter p
 func (ir *iRemote) getter_float(p string) float64 {
 	param := fmt.Sprintf("%s.%s", ir.identifier(), p)
-	return getParameterFloat(param)
+	val, err := getParameterFloat(param)
+	if err != nil {
+		fmt.Println(err)
+	}
+	return val
 }
 
 // setter_float sets the value v of an int parameter p
 func (ir *iRemote) setter_float(p string, v float32) {
 	param := fmt.Sprintf("%s.%s", ir.identifier(), p)
-	setParameterFloat(param, float32(v))
+	err := setParameterFloat(param, float32(v))
+	if err != nil {
+		fmt.Println(err)
+	}
 }
 
 // getter_string returns the value of a string parameter p
 func (ir *iRemote) getter_string(p string) string {
 	param := fmt.Sprintf("%s.%s", ir.identifier(), p)
-	return getParameterString(param)
+	val, err := getParameterString(param)
+	if err != nil {
+		fmt.Println(err)
+	}
+	return val
 }
 
 // setter_string sets the value v of a string parameter p
 func (ir *iRemote) setter_string(p, v string) {
 	param := fmt.Sprintf("%s.%s", ir.identifier(), p)
-	setParameterString(param, v)
+	err := setParameterString(param, v)
+	if err != nil {
+		fmt.Println(err)
+	}
 }

remote.go

@@ -26,26 +26,42 @@ func (r *Remote) String() string {
 
 // Login logs into the API
 // then it intializes the pooler
-func (r *Remote) Login() {
+func (r *Remote) Login() error {
-	login(r.Kind.Name)
+	err := login(r.Kind.Name)
+	if err != nil {
+		return err
+	}
 	r.pooler = newPooler(r.Kind)
+	return nil
 }
 
 // Logout logs out of the API
 // it also terminates the pooler
-func (r *Remote) Logout() {
+func (r *Remote) Logout() error {
 	r.pooler.run = false
-	logout(r.Kind.Name)
+	err := logout(r.Kind.Name)
+	if err != nil {
+		return err
+	}
+	return nil
 }
 
 // Type returns the type of Voicemeeter (basic, banana, potato)
 func (r *Remote) Type() string {
-	return getVMType()
+	val, err := getVMType()
+	if err != nil {
+		fmt.Println(err)
+	}
+	return val
 }
 
 // Version returns the version of Voicemeeter as a string
 func (r *Remote) Version() string {
-	return getVersion()
+	val, err := getVersion()
+	if err != nil {
+		fmt.Println(err)
+	}
+	return val
 }
 
 // Pdirty returns true iff a parameter value has changed
@@ -60,7 +76,11 @@ func (r *Remote) Mdirty() bool {
 
 // Gets a float parameter value
 func (r *Remote) GetFloat(name string) float64 {
-	return getParameterFloat(name)
+	val, err := getParameterFloat(name)
+	if err != nil {
+		fmt.Println(err)
+	}
+	return val
 }
 
 // Sets a float paramter value
@@ -70,7 +90,11 @@ func (r *Remote) SetFloat(name string, value float32) {
 
 // Gets a string parameter value
 func (r *Remote) GetString(name string) string {
-	return getParameterString(name)
+	val, err := getParameterString(name)
+	if err != nil {
+		fmt.Println(err)
+	}
+	return val
 }
 
 // Sets a string paramter value