add support for field arrays in hci packet definitions

bumble/hci.py

@@ -1445,8 +1445,14 @@ class HCI_Object:
     @staticmethod
     def init_from_fields(hci_object, fields, values):
         if isinstance(values, dict):
-            for field_name, _ in fields:
+            for field in fields:
-                setattr(hci_object, field_name, values[field_name])
+                if isinstance(field, list):
+                    # The field is an array, up-level the array field names
+                    for sub_field_name, _ in field:
+                        setattr(hci_object, sub_field_name, values[sub_field_name])
+                else:
+                    field_name = field[0]
+                    setattr(hci_object, field_name, values[field_name])
         else:
             for field_name, field_value in zip(fields, values):
                 setattr(hci_object, field_name, field_value)
@@ -1456,133 +1462,161 @@ class HCI_Object:
         parsed = HCI_Object.dict_from_bytes(data, offset, fields)
         HCI_Object.init_from_fields(hci_object, parsed.keys(), parsed.values())
 
+    @staticmethod
+    def parse_field(data, offset, field_type):
+        # The field_type may be a dictionary with a mapper, parser, and/or size
+        if isinstance(field_type, dict):
+            if 'size' in field_type:
+                field_type = field_type['size']
+            elif 'parser' in field_type:
+                field_type = field_type['parser']
+
+        # Parse the field
+        if field_type == '*':
+            # The rest of the bytes
+            field_value = data[offset:]
+            return (field_value, len(field_value))
+        if field_type == 1:
+            # 8-bit unsigned
+            return (data[offset], 1)
+        if field_type == -1:
+            # 8-bit signed
+            return (struct.unpack_from('b', data, offset)[0], 1)
+        if field_type == 2:
+            # 16-bit unsigned
+            return (struct.unpack_from('<H', data, offset)[0], 2)
+        if field_type == '>2':
+            # 16-bit unsigned big-endian
+            return (struct.unpack_from('>H', data, offset)[0], 2)
+        if field_type == -2:
+            # 16-bit signed
+            return (struct.unpack_from('<h', data, offset)[0], 2)
+        if field_type == 3:
+            # 24-bit unsigned
+            padded = data[offset : offset + 3] + bytes([0])
+            return (struct.unpack('<I', padded)[0], 3)
+        if field_type == 4:
+            # 32-bit unsigned
+            return (struct.unpack_from('<I', data, offset)[0], 4)
+        if field_type == '>4':
+            # 32-bit unsigned big-endian
+            return (struct.unpack_from('>I', data, offset)[0], 4)
+        if isinstance(field_type, int) and 4 < field_type <= 256:
+            # Byte array (from 5 up to 256 bytes)
+            return (data[offset : offset + field_type], field_type)
+        if callable(field_type):
+            new_offset, field_value = field_type(data, offset)
+            return (field_value, new_offset - offset)
+
+        raise ValueError(f'unknown field type {field_type}')
+
     @staticmethod
     def dict_from_bytes(data, offset, fields):
         result = collections.OrderedDict()
-        for (field_name, field_type) in fields:
+        for field in fields:
-            # The field_type may be a dictionary with a mapper, parser, and/or size
+            if isinstance(field, list):
-            if isinstance(field_type, dict):
+                # This is an array field, starting with a 1-byte item count.
-                if 'size' in field_type:
+                item_count = data[offset]
-                    field_type = field_type['size']
-                elif 'parser' in field_type:
-                    field_type = field_type['parser']
-
-            # Parse the field
-            if field_type == '*':
-                # The rest of the bytes
-                field_value = data[offset:]
-                offset += len(field_value)
-            elif field_type == 1:
-                # 8-bit unsigned
-                field_value = data[offset]
                 offset += 1
-            elif field_type == -1:
+                for _ in range(item_count):
-                # 8-bit signed
+                    for sub_field_name, sub_field_type in field:
-                field_value = struct.unpack_from('b', data, offset)[0]
+                        value, size = HCI_Object.parse_field(
-                offset += 1
+                            data, offset, sub_field_type
-            elif field_type == 2:
+                        )
-                # 16-bit unsigned
+                        result.setdefault(sub_field_name, []).append(value)
-                field_value = struct.unpack_from('<H', data, offset)[0]
+                        offset += size
-                offset += 2
+                continue
-            elif field_type == '>2':
-                # 16-bit unsigned big-endian
-                field_value = struct.unpack_from('>H', data, offset)[0]
-                offset += 2
-            elif field_type == -2:
-                # 16-bit signed
-                field_value = struct.unpack_from('<h', data, offset)[0]
-                offset += 2
-            elif field_type == 3:
-                # 24-bit unsigned
-                padded = data[offset : offset + 3] + bytes([0])
-                field_value = struct.unpack('<I', padded)[0]
-                offset += 3
-            elif field_type == 4:
-                # 32-bit unsigned
-                field_value = struct.unpack_from('<I', data, offset)[0]
-                offset += 4
-            elif field_type == '>4':
-                # 32-bit unsigned big-endian
-                field_value = struct.unpack_from('>I', data, offset)[0]
-                offset += 4
-            elif isinstance(field_type, int) and 4 < field_type <= 256:
-                # Byte array (from 5 up to 256 bytes)
-                field_value = data[offset : offset + field_type]
-                offset += field_type
-            elif callable(field_type):
-                offset, field_value = field_type(data, offset)
-            else:
-                raise ValueError(f'unknown field type {field_type}')
 
+            field_name, field_type = field
+            field_value, field_size = HCI_Object.parse_field(data, offset, field_type)
             result[field_name] = field_value
+            offset += field_size
 
         return result
 
+    @staticmethod
+    def serialize_field(field_value, field_type):
+        # The field_type may be a dictionary with a mapper, parser, serializer,
+        # and/or size
+        serializer = None
+        if isinstance(field_type, dict):
+            if 'serializer' in field_type:
+                serializer = field_type['serializer']
+            if 'size' in field_type:
+                field_type = field_type['size']
+
+        # Serialize the field
+        if serializer:
+            field_bytes = serializer(field_value)
+        elif field_type == 1:
+            # 8-bit unsigned
+            field_bytes = bytes([field_value])
+        elif field_type == -1:
+            # 8-bit signed
+            field_bytes = struct.pack('b', field_value)
+        elif field_type == 2:
+            # 16-bit unsigned
+            field_bytes = struct.pack('<H', field_value)
+        elif field_type == '>2':
+            # 16-bit unsigned big-endian
+            field_bytes = struct.pack('>H', field_value)
+        elif field_type == -2:
+            # 16-bit signed
+            field_bytes = struct.pack('<h', field_value)
+        elif field_type == 3:
+            # 24-bit unsigned
+            field_bytes = struct.pack('<I', field_value)[0:3]
+        elif field_type == 4:
+            # 32-bit unsigned
+            field_bytes = struct.pack('<I', field_value)
+        elif field_type == '>4':
+            # 32-bit unsigned big-endian
+            field_bytes = struct.pack('>I', field_value)
+        elif field_type == '*':
+            if isinstance(field_value, int):
+                if 0 <= field_value <= 255:
+                    field_bytes = bytes([field_value])
+                else:
+                    raise ValueError('value too large for *-typed field')
+            else:
+                field_bytes = bytes(field_value)
+        elif isinstance(field_value, (bytes, bytearray)) or hasattr(
+            field_value, 'to_bytes'
+        ):
+            field_bytes = bytes(field_value)
+            if isinstance(field_type, int) and 4 < field_type <= 256:
+                # Truncate or pad with zeros if the field is too long or too short
+                if len(field_bytes) < field_type:
+                    field_bytes += bytes(field_type - len(field_bytes))
+                elif len(field_bytes) > field_type:
+                    field_bytes = field_bytes[:field_type]
+        else:
+            raise ValueError(f"don't know how to serialize type {type(field_value)}")
+
+        return field_bytes
+
     @staticmethod
     def dict_to_bytes(hci_object, fields):
         result = bytearray()
-        for (field_name, field_type) in fields:
+        for field in fields:
-            # The field_type may be a dictionary with a mapper, parser, serializer,
+            if isinstance(field, list):
-            # and/or size
+                # The field is an array. The serialized form starts with a 1-byte
-            serializer = None
+                # item count. We use the length of the first array field as the
-            if isinstance(field_type, dict):
+                # array count, since all array fields have the same number of items.
-                if 'serializer' in field_type:
+                item_count = len(hci_object[field[0][0]])
-                    serializer = field_type['serializer']
+                result += bytes([item_count]) + b''.join(
-                if 'size' in field_type:
+                    b''.join(
-                    field_type = field_type['size']
+                        HCI_Object.serialize_field(
-
+                            hci_object[sub_field_name][i], sub_field_type
-            # Serialize the field
+                        )
-            field_value = hci_object[field_name]
+                        for sub_field_name, sub_field_type in field
-            if serializer:
+                    )
-                field_bytes = serializer(field_value)
+                    for i in range(item_count)
-            elif field_type == 1:
-                # 8-bit unsigned
-                field_bytes = bytes([field_value])
-            elif field_type == -1:
-                # 8-bit signed
-                field_bytes = struct.pack('b', field_value)
-            elif field_type == 2:
-                # 16-bit unsigned
-                field_bytes = struct.pack('<H', field_value)
-            elif field_type == '>2':
-                # 16-bit unsigned big-endian
-                field_bytes = struct.pack('>H', field_value)
-            elif field_type == -2:
-                # 16-bit signed
-                field_bytes = struct.pack('<h', field_value)
-            elif field_type == 3:
-                # 24-bit unsigned
-                field_bytes = struct.pack('<I', field_value)[0:3]
-            elif field_type == 4:
-                # 32-bit unsigned
-                field_bytes = struct.pack('<I', field_value)
-            elif field_type == '>4':
-                # 32-bit unsigned big-endian
-                field_bytes = struct.pack('>I', field_value)
-            elif field_type == '*':
-                if isinstance(field_value, int):
-                    if 0 <= field_value <= 255:
-                        field_bytes = bytes([field_value])
-                    else:
-                        raise ValueError('value too large for *-typed field')
-                else:
-                    field_bytes = bytes(field_value)
-            elif isinstance(field_value, (bytes, bytearray)) or hasattr(
-                field_value, 'to_bytes'
-            ):
-                field_bytes = bytes(field_value)
-                if isinstance(field_type, int) and 4 < field_type <= 256:
-                    # Truncate or Pad with zeros if the field is too long or too short
-                    if len(field_bytes) < field_type:
-                        field_bytes += bytes(field_type - len(field_bytes))
-                    elif len(field_bytes) > field_type:
-                        field_bytes = field_bytes[:field_type]
-            else:
-                raise ValueError(
-                    f"don't know how to serialize type {type(field_value)}"
                 )
+                continue
 
-            result += field_bytes
+            (field_name, field_type) = field
+            result += HCI_Object.serialize_field(hci_object[field_name], field_type)
 
         return bytes(result)
 
@@ -1617,48 +1651,73 @@ class HCI_Object:
         return str(value)
 
     @staticmethod
-    def format_fields(hci_object, keys, indentation='', value_mappers=None):
+    def stringify_field(
-        if not keys:
+        field_name, field_type, field_value, indentation, value_mappers
-            return ''
+    ):
+        value_mapper = None
+        if isinstance(field_type, dict):
+            # Get the value mapper from the specifier
+            value_mapper = field_type.get('mapper')
 
-        # Measure the widest field name
+        # Check if there's a matching mapper passed
-        max_field_name_length = max(
+        if value_mappers:
-            (len(key[0] if isinstance(key, tuple) else key) for key in keys)
+            value_mapper = value_mappers.get(field_name, value_mapper)
+
+        # Map the value if we have a mapper
+        if value_mapper is not None:
+            field_value = value_mapper(field_value)
+
+        # Get the string representation of the value
+        return HCI_Object.format_field_value(
+            field_value, indentation=indentation + '  '
         )
 
+    @staticmethod
+    def format_fields(hci_object, fields, indentation='', value_mappers=None):
+        if not fields:
+            return ''
+
         # Build array of formatted key:value pairs
-        fields = []
+        field_strings = []
-        for key in keys:
+        for field in fields:
-            value_mapper = None
+            if isinstance(field, list):
-            if isinstance(key, tuple):
+                for sub_field in field:
-                # The key has an associated specifier
+                    sub_field_name, sub_field_type = sub_field
-                key, specifier = key
+                    item_count = len(hci_object[sub_field_name])
+                    for i in range(item_count):
+                        field_strings.append(
+                            (
+                                f'{sub_field_name}[{i}]',
+                                HCI_Object.stringify_field(
+                                    sub_field_name,
+                                    sub_field_type,
+                                    hci_object[sub_field_name][i],
+                                    indentation,
+                                    value_mappers,
+                                ),
+                            ),
+                        )
+                continue
 
-                # Get the value mapper from the specifier
+            field_name, field_type = field
-                if isinstance(specifier, dict):
+            field_value = hci_object[field_name]
-                    value_mapper = specifier.get('mapper')
+            field_strings.append(
-
+                (
-            # Get the value for the field
+                    field_name,
-            value = hci_object[key]
+                    HCI_Object.stringify_field(
-
+                        field_name, field_type, field_value, indentation, value_mappers
-            # Check if there's a matching mapper passed
+                    ),
-            if value_mappers:
+                ),
-                value_mapper = value_mappers.get(key, value_mapper)
-
-            # Map the value if we have a mapper
-            if value_mapper is not None:
-                value = value_mapper(value)
-
-            # Get the string representation of the value
-            value_str = HCI_Object.format_field_value(
-                value, indentation=indentation + '  '
             )
 
-            # Add the field to the formatted result
+        # Measure the widest field name
-            key_str = color(f'{key + ":":{1 + max_field_name_length}}', 'cyan')
+        max_field_name_length = max(len(s[0]) for s in field_strings)
-            fields.append(f'{indentation}{key_str} {value_str}')
+        sep = ':'
-
+        return '\n'.join(
-        return '\n'.join(fields)
+            f'{indentation}'
+            f'{color(f"{field_name + sep:{1 + max_field_name_length}}", "cyan")} {field_value}'
+            for field_name, field_value in field_strings
+        )
 
     def __bytes__(self):
         return self.to_bytes()
@@ -3769,9 +3828,7 @@ class HCI_LE_Set_Extended_Advertising_Parameters_Command(HCI_Command):
             'advertising_data',
             {
                 'parser': HCI_Object.parse_length_prefixed_bytes,
-                'serializer': functools.partial(
+                'serializer': HCI_Object.serialize_length_prefixed_bytes,
-                    HCI_Object.serialize_length_prefixed_bytes
-                ),
             },
         ),
     ]
@@ -3819,9 +3876,7 @@ class HCI_LE_Set_Extended_Advertising_Data_Command(HCI_Command):
             'scan_response_data',
             {
                 'parser': HCI_Object.parse_length_prefixed_bytes,
-                'serializer': functools.partial(
+                'serializer': HCI_Object.serialize_length_prefixed_bytes,
-                    HCI_Object.serialize_length_prefixed_bytes
-                ),
             },
         ),
     ]
@@ -3849,73 +3904,21 @@ class HCI_LE_Set_Extended_Scan_Response_Data_Command(HCI_Command):
 
 
 # -----------------------------------------------------------------------------
-@HCI_Command.command(fields=None)
+@HCI_Command.command(
+    [
+        ('enable', 1),
+        [
+            ('advertising_handles', 1),
+            ('durations', 2),
+            ('max_extended_advertising_events', 1),
+        ],
+    ]
+)
 class HCI_LE_Set_Extended_Advertising_Enable_Command(HCI_Command):
     '''
     See Bluetooth spec @ 7.8.56 LE Set Extended Advertising Enable Command
     '''
 
-    @classmethod
-    def from_parameters(cls, parameters):
-        enable = parameters[0]
-        num_sets = parameters[1]
-        advertising_handles = []
-        durations = []
-        max_extended_advertising_events = []
-        offset = 2
-        for _ in range(num_sets):
-            advertising_handles.append(parameters[offset])
-            durations.append(struct.unpack_from('<H', parameters, offset + 1)[0])
-            max_extended_advertising_events.append(parameters[offset + 3])
-            offset += 4
-
-        return cls(
-            enable, advertising_handles, durations, max_extended_advertising_events
-        )
-
-    def __init__(
-        self, enable, advertising_handles, durations, max_extended_advertising_events
-    ):
-        super().__init__(HCI_LE_SET_EXTENDED_ADVERTISING_ENABLE_COMMAND)
-        self.enable = enable
-        self.advertising_handles = advertising_handles
-        self.durations = durations
-        self.max_extended_advertising_events = max_extended_advertising_events
-
-        self.parameters = bytes([enable, len(advertising_handles)]) + b''.join(
-            [
-                struct.pack(
-                    '<BHB',
-                    advertising_handles[i],
-                    durations[i],
-                    max_extended_advertising_events[i],
-                )
-                for i in range(len(advertising_handles))
-            ]
-        )
-
-    def __str__(self):
-        fields = [('enable:', self.enable)]
-        for i, advertising_handle in enumerate(self.advertising_handles):
-            fields.append(
-                (f'advertising_handle[{i}]:             ', advertising_handle)
-            )
-            fields.append((f'duration[{i}]:                       ', self.durations[i]))
-            fields.append(
-                (
-                    f'max_extended_advertising_events[{i}]:',
-                    self.max_extended_advertising_events[i],
-                )
-            )
-
-        return (
-            color(self.name, 'green')
-            + ':\n'
-            + '\n'.join(
-                [color(field[0], 'cyan') + ' ' + str(field[1]) for field in fields]
-            )
-        )
-
 
 # -----------------------------------------------------------------------------
 @HCI_Command.command(
@@ -4066,7 +4069,10 @@ class HCI_LE_Set_Extended_Scan_Parameters_Command(HCI_Command):
             color(self.name, 'green')
             + ':\n'
             + '\n'.join(
-                [color(field[0], 'cyan') + ' ' + str(field[1]) for field in fields]
+                [
+                    color('  ' + field[0], 'cyan') + ' ' + str(field[1])
+                    for field in fields
+                ]
             )
         )
 
@@ -4242,7 +4248,10 @@ class HCI_LE_Extended_Create_Connection_Command(HCI_Command):
             color(self.name, 'green')
             + ':\n'
             + '\n'.join(
-                [color(field[0], 'cyan') + ' ' + str(field[1]) for field in fields]
+                [
+                    color('  ' + field[0], 'cyan') + ' ' + str(field[1])
+                    for field in fields
+                ]
             )
         )
 
@@ -5205,7 +5214,7 @@ class HCI_Number_Of_Completed_Packets_Event(HCI_Event):
     def __str__(self):
         lines = [
             color(self.name, 'magenta') + ':',
-            color('  number_of_handles:         ', 'cyan')
+            color('  number_of_handles:        ', 'cyan')
             + f'{len(self.connection_handles)}',
         ]
         for i, connection_handle in enumerate(self.connection_handles):

tests/hci_test.py

@@ -46,6 +46,7 @@ from bumble.hci import (
     HCI_LE_Set_Advertising_Parameters_Command,
     HCI_LE_Set_Default_PHY_Command,
     HCI_LE_Set_Event_Mask_Command,
+    HCI_LE_Set_Extended_Advertising_Enable_Command,
     HCI_LE_Set_Extended_Scan_Parameters_Command,
     HCI_LE_Set_Random_Address_Command,
     HCI_LE_Set_Scan_Enable_Command,
@@ -422,6 +423,25 @@ def test_HCI_LE_Set_Extended_Scan_Parameters_Command():
     basic_check(command)
 
 
+# -----------------------------------------------------------------------------
+def test_HCI_LE_Set_Extended_Advertising_Enable_Command():
+    command = HCI_Packet.from_bytes(
+        bytes.fromhex('0139200e010301050008020600090307000a')
+    )
+    assert command.enable == 1
+    assert command.advertising_handles == [1, 2, 3]
+    assert command.durations == [5, 6, 7]
+    assert command.max_extended_advertising_events == [8, 9, 10]
+
+    command = HCI_LE_Set_Extended_Advertising_Enable_Command(
+        enable=1,
+        advertising_handles=[1, 2, 3],
+        durations=[5, 6, 7],
+        max_extended_advertising_events=[8, 9, 10],
+    )
+    basic_check(command)
+
+
 # -----------------------------------------------------------------------------
 def test_address():
     a = Address('C4:F2:17:1A:1D:BB')
@@ -478,6 +498,7 @@ def run_test_commands():
     test_HCI_LE_Read_Remote_Features_Command()
     test_HCI_LE_Set_Default_PHY_Command()
     test_HCI_LE_Set_Extended_Scan_Parameters_Command()
+    test_HCI_LE_Set_Extended_Advertising_Enable_Command()
 
 
 # -----------------------------------------------------------------------------