#65 Fix mapping of char from rune to byte

go/byteconverter.go

@@ -161,27 +161,13 @@ func ByteSliceToFloat64Slice(slice []byte) []float64 {
 	return result
 }
 
-func ByteSliceToRuneSlice(slice []byte) []rune {
-	result := make([]rune, len(slice))
-	for idx, b := range slice {
-		result[idx] = rune(b)
-	}
-	return result
-}
-
-func RuneSliceToByteSlice(slice []rune) []byte {
-	result := make([]byte, len(slice))
-	for idx, b := range slice {
-		result[idx] = byte(b)
-	}
-	return result
-}
 
 func ByteSliceToString(slice []byte) string {
 	n := bytes.IndexByte(slice, 0)
 	return string(slice[:n])
 }
 
+// Todo: This would break encoding of UTF-8 chars. Evaluate []byte(str)
 func StringToByteSlice(str string, maxLen uint64) ([]byte, error) {
 	runes := []rune(str)
 	bytes := make([]byte, maxLen, maxLen)

go/changelog.txt

@@ -102,3 +102,6 @@
 
 2025-10-07: 2.0.17 (9ad863d)
 - Fix bool arrays in setters
+
+2026-04-15: 2.0.18 (7685cab7)
+- Fix mapping of char from rune to byte (Issue: https://github.com/Tinkerforge/generators/issues/65)

go/example_authenticate.go

@@ -34,7 +34,7 @@ func main() {
 		ipcon.Enumerate()            // then trigger enumerate.
 	})
 
-	ipcon.RegisterEnumerateCallback(func(uid string, connectedUid string, position rune, hardwareVersion [3]uint8,
+	ipcon.RegisterEnumerateCallback(func(uid string, connectedUid string, position byte, hardwareVersion [3]uint8,
 	                                     firmwareVersion [3]uint8, deviceIdentifier uint16, enumerationType ipconnection.EnumerationType) {
 		fmt.Printf("UID:               %s\n", uid)
 		switch enumerationType {

go/example_enumerate.go

@@ -15,7 +15,7 @@ func main() {
 	defer ipcon.Disconnect()
 	// Don't use device before ipcon is connected.
 
-	ipcon.RegisterEnumerateCallback(func(uid string, connectedUid string, position rune, hardwareVersion [3]uint8,
+	ipcon.RegisterEnumerateCallback(func(uid string, connectedUid string, position byte, hardwareVersion [3]uint8,
 	                                     firmwareVersion [3]uint8, deviceIdentifier uint16, enumerationType ipconnection.EnumerationType) {
 		fmt.Printf("UID:               %s\n", uid)
 		switch enumerationType {

go/generate_go_bindings.py

@@ -123,7 +123,7 @@ def get_go_constants(self):
             enum_values = []
 
             for constant in constant_group.get_constants():
-                value = str(constant.get_value()) if not "rune" in constant_type else "'" + constant.get_value() + "'"
+                value = str(constant.get_value()) if not "byte" in constant_type else "'" + constant.get_value() + "'"
 
                 if constant_type == "bool":
                     value = value.lower()
@@ -187,16 +187,14 @@ def go_fill_payload(self, elements, bufferName):
     def go_read_results(self, elements, bufferName, low_level_in_bits=True):
         read_results = []
         for elem in elements:
-            size = elem.get_size()
-
             if elem.get_level() == 'low' and elem.get_role() == 'stream_chunk_data':
                 read_results.append("copy({name}[:], ByteSliceTo{type}Slice({buf}.Next({mult} * {chunk_size}/8)))".format(buf=bufferName, name=elem.get_go_name(), type=elem.get_go_type(ignore_cardinality=True).title(), chunk_size= elem.get_cardinality(), mult =  go_common.get_go_type_size(elem.get_go_type(ignore_cardinality=True))))
                 continue
 
-            if "rune" in elem.get_go_type() and elem.get_cardinality() == 1:
-                read_results.append("{ret_name} = rune({buf}.Next(1)[0])".format(buf=bufferName, ret_name=elem.get_go_name()))
-            elif "rune" in elem.get_go_type():
-                read_results.append("copy({ret_name}[:], ByteSliceTo{type}Slice({buf}.Next({len})))".format(buf=bufferName, ret_name=elem.get_go_name(), type=elem.get_go_type(ignore_cardinality=True).title(), len=elem.get_cardinality()))
+            if "byte" in elem.get_go_type() and elem.get_cardinality() == 1:
+                read_results.append("{ret_name} = {buf}.Next(1)[0]".format(buf=bufferName, ret_name=elem.get_go_name()))
+            elif "byte" in elem.get_go_type():
+                read_results.append("copy({ret_name}[:], {buf}.Next({len}))".format(buf=bufferName, ret_name=elem.get_go_name(), type=elem.get_go_type(ignore_cardinality=True).title(), len=elem.get_cardinality()))
             elif "bool" in elem.get_go_type() and elem.get_cardinality() > 1:
                 read_results.append("copy({ret_name}[:], ByteSliceTo{type}Slice({buf}.Next({len})))".format(buf=bufferName, ret_name=elem.get_go_name(), type=elem.get_go_type(ignore_cardinality=True).title(), len=math.ceil(elem.get_cardinality() / 8)))
             elif elem.get_go_type() == "string":

go/go_common.py

@@ -246,7 +246,7 @@ def get_go_type(self, ignore_cardinality=False, ignore_constant_group=False, con
             return self.get_constant_group(index=self.get_indices()[0]).get_name().camel
 
         if self.get_type() == 'char':
-            element_type = 'rune'
+            element_type = 'byte'
         elif self.get_type() == 'string':
             return 'string'
         elif self.get_type() == 'bool':
@@ -281,7 +281,7 @@ def get_go_type(self):
     'uint64': 'uint64',
     'float':  'float32',
     'bool':   'bool',
-    'char':   'rune',
+    'char':   'byte',
     'string': 'string'
 }
 
@@ -296,7 +296,7 @@ def get_go_type(self):
     'uint64': 64,
     'float32':32,
     'bool':   1,
-    'rune':   8,
+    'byte':   8,
     'string': 'string'
 }
 

go/ipcon_handle.go

@@ -75,7 +75,7 @@ func (ipcon *IPConnection) RegisterDisconnectCallback(fn func(DisconnectReason))
 //     For the bottommost Brick in a stack it is "0".
 //     With this information it is possible to reconstruct the complete network topology.
 //
-// * position rune -  For Bricks: '0' - '8' (position in stack). For Bricklets: 'a' - 'd' (position on Brick).
+// * position byte -  For Bricks: '0' - '8' (position in stack). For Bricklets: 'a' - 'd' (position on Brick).
 //
 // * hardwareVersion [3]uint8 - Major, minor and release number for hardware version.
 //
@@ -88,7 +88,7 @@ func (ipcon *IPConnection) RegisterDisconnectCallback(fn func(DisconnectReason))
 //     For example: master_brick.DeviceIdentifier or ambient_light_bricklet.DeviceIdentifier.
 //
 // * enumerationType EnumerationType - Type of enumeration.
-func (ipcon *IPConnection) RegisterEnumerateCallback(fn func(uid string, connectedUID string, position rune, hardwareVersion [3]uint8, firmwareVersion [3]uint8, deviceIdentifier uint16, enumerationType EnumerationType)) uint64 {
+func (ipcon *IPConnection) RegisterEnumerateCallback(fn func(uid string, connectedUID string, position byte, hardwareVersion [3]uint8, firmwareVersion [3]uint8, deviceIdentifier uint16, enumerationType EnumerationType)) uint64 {
 	wrapper := func(bytes []byte) {
 		var header internal.PacketHeader
 
@@ -100,7 +100,7 @@ func (ipcon *IPConnection) RegisterEnumerateCallback(fn func(uid string, connect
 		bytes = bytes[8:]
 		uid := internal.ByteSliceToString(bytes[0:8])
 		connectedUID := internal.ByteSliceToString(bytes[8:16])
-		position := rune(bytes[16])
+		position := bytes[16] // Todo: Evaluate a custom datatype with .String() etc.
 		hardwareVersion := [3]uint8{bytes[17], bytes[18], bytes[19]}
 		firmwareVersion := [3]uint8{bytes[20], bytes[21], bytes[22]}
 		deviceIdentifier := binary.LittleEndian.Uint16(bytes[23:25])