qmk-firmware/lib/python/qmk/xap/gen_firmware/header_generator.py

"""This script generates the XAP protocol generated header to be compiled into QMK.
"""
import re
from fnvhash import fnv1a_32

from qmk.commands import dump_lines
from qmk.git import git_get_version
from qmk.constants import GPL2_HEADER_C_LIKE, GENERATED_HEADER_C_LIKE
from qmk.xap.common import latest_xap_defs, route_conditions


def _append_route_defines(lines, container, container_id=None, route_stack=None):
    """Handles building the list of the XAP routes, combining parent and child names together, as well as the route number.
    """
    if route_stack is None:
        route_stack = [container]
    else:
        route_stack.append(container)

    route_name = '_'.join([r['define'] for r in route_stack])

    if container_id:
        lines.append(f'#define {route_name} {container_id}')

    if 'routes' in container:
        for route_id in container['routes']:
            route = container['routes'][route_id]
            _append_route_defines(lines, route, route_id, route_stack)

    route_stack.pop()


def _append_route_masks(lines, container, container_id=None, route_stack=None):
    """Handles creating the equivalent XAP route masks, for capabilities checks. Forces value of `0` if disabled in the firmware.
    """
    if route_stack is None:
        route_stack = [container]
    else:
        route_stack.append(container)

    route_name = '_'.join([r['define'] for r in route_stack])
    condition = route_conditions(route_stack)

    if container_id:
        if condition:
            lines.append('')
            lines.append(f'#if {condition}')

        lines.append(f'#define {route_name}_MASK (1ul << ({route_name}))')

        if condition:
            lines.append(f'#else  // {condition}')
            lines.append(f'#define {route_name}_MASK 0')
            lines.append(f'#endif  // {condition}')
            lines.append('')

    if 'routes' in container:
        for route_id in container['routes']:
            route = container['routes'][route_id]
            _append_route_masks(lines, route, route_id, route_stack)

    route_stack.pop()


def _append_route_capabilities(lines, container, container_id=None, route_stack=None):
    """Handles creating the equivalent XAP route masks, for capabilities checks. Forces value of `0` if disabled in the firmware.
    """
    if route_stack is None:
        route_stack = [container]
    else:
        route_stack.append(container)

    route_name = '_'.join([r['define'] for r in route_stack])

    if 'routes' in container:
        lines.append('')
        lines.append(f'#define {route_name}_CAPABILITIES (0 \\')

        if 'routes' in container:
            for route_id in container['routes']:
                route = container['routes'][route_id]
                route_stack.append(route)
                child_name = '_'.join([r['define'] for r in route_stack])
                lines.append(f'  | ({child_name}_MASK) \\')
                route_stack.pop()

        lines.append('  )')

    if 'routes' in container:
        for route_id in container['routes']:
            route = container['routes'][route_id]
            _append_route_capabilities(lines, route, route_id, route_stack)

    route_stack.pop()


def _append_types(lines, container):
    """Handles creating the various constants, types, defines, etc.
    """
    response_flags = container.get('response_flags', {})
    prefix = response_flags['define_prefix']
    for key, value in response_flags['bits'].items():
        define = value.get('define')
        lines.append(f'#define {prefix}_{define} (1ul << ({key}))')

    # Add special
    lines.append(f'#define {prefix}_FAILED 0x00')

    # TODO: define this in xap_*.hjson
    lines.append(
        '''
typedef uint8_t  xap_identifier_t;
typedef uint8_t  xap_response_flags_t;
typedef uint16_t xap_token_t;

typedef struct {
    xap_token_t token;
    uint8_t     length;
} xap_request_header_t;

typedef struct {
    xap_token_t          token;
    xap_response_flags_t flags;
    uint8_t              length;
} xap_response_header_t;'''
    )


def generate_header(output_file, keyboard):
    """Generates the XAP protocol header file, generated during normal build.
    """
    xap_defs = latest_xap_defs()

    # Preamble
    lines = [GPL2_HEADER_C_LIKE, GENERATED_HEADER_C_LIKE, '#pragma once', '']

    # Versions
    prog = re.compile(r'^(\d+)\.(\d+)\.(\d+)')
    b = prog.match(xap_defs['version'])
    lines.append(f'#define XAP_BCD_VERSION 0x{int(b.group(1)):02d}{int(b.group(2)):02d}{int(b.group(3)):04d}ul')
    b = prog.match(git_get_version() or "")
    lines.append(f'#define QMK_BCD_VERSION 0x{int(b.group(1)):02d}{int(b.group(2)):02d}{int(b.group(3)):04d}ul')
    keyboard_id = fnv1a_32(bytes(keyboard, 'utf-8'))
    lines.append(f'#define XAP_KEYBOARD_IDENTIFIER 0x{keyboard_id:08X}ul')
    lines.append('')

    # Types
    _append_types(lines, xap_defs)
    lines.append('')

    # Append the route and command defines
    _append_route_defines(lines, xap_defs)
    lines.append('')
    _append_route_masks(lines, xap_defs)
    lines.append('')
    _append_route_capabilities(lines, xap_defs)
    lines.append('')

    dump_lines(output_file, lines)