gen_xlib.py

#!/usr/bin/env python
# pkg-config --variable=xcbincludedir xcb-proto

import re
import sys
from collections import namedtuple

def err(*args):
    sys.stderr.write(' '.join(str(a) for a in args) + '\n')

PyType = namedtuple('PyType', 'name is_complex')

py_types = {
    ('int8_t',)  : PyType('rq.Int8', False),
    ('int16_t',) : PyType('rq.Int16', False),
    ('int32_t',) : PyType('rq.Int32', False),
    ('uint8_t',) : PyType('rq.Card8', False),
    ('uint16_t',): PyType('rq.Card16', False),
    ('uint32_t',): PyType('rq.Card32', False),
}

py_level = 0

ext_requests = {}
ext_ge_events = {}
ext_events = {}
ext_errors = {}

def uncamel(s):
    s = re.sub('(.)([A-Z][a-z]+)', r'\1_\2', s)
    s = re.sub('([a-z0-9])([A-Z])', r'\1_\2', s)
    return s.lower()

def py_out(fmt=None, *args, indent=True, endl=True):
    if fmt is None:
        print()
        return
    if indent:
        indent = ' ' * py_level * 4
    else:
        indent = ''
    code = (fmt % args).lstrip()
    print(indent + code, end='\n' if endl else '')

def py_indent(level):
    global py_level
    py_level += level

def py_name(name):
    if isinstance(name, str):
        pyn = name
    else:
        prefix_len = len(module.namespace.prefix)
        if len(name) == 2 and name[1] in ('_fields', '_reply', '_request'):
            pyn = name[1:]
        else:
            assert len(name) >= prefix_len and name[:prefix_len] == module.namespace.prefix, \
                    'bad name prefix: %s / %s' % (str(name), str(module.namespace.prefix))
            pyn = name[prefix_len:]
        assert len(pyn) == 1, '%s: %s' % (name, pyn)
        pyn = pyn[0]
    if module.namespace.is_ext:
        if 'XInputExtension' == module.namespace.ext_xname:
            pass
            # Conflicts: UngrabDevice, XIUngrabDevice.
            # if pyn.startswith('XI'):
            #     pyn = pyn[2:]
    if re.match('^[A-Za-z_]', pyn) is None:
        pyn = '_' + pyn
    elif pyn in ('None', 'or', 'and',
                 'if', 'class', 'while',
                 'def', 'else', 'elif'):
        pyn = '_' + pyn
    return pyn

def py_open(self):
    py_out('# Automatically generated file; DO NOT EDIT.')
    py_out('# Generated from: %s' % self.namespace.path)
    py_out()
    py_out('from Xlib.protocol import rq, structs')
    py_out()
    py_out()
    if module.namespace.is_ext:
        # FIXME
        py_types[('xcb', 'WINDOW')] = PyType('rq.Window', False)
        py_types[('xcb', 'POINT')] = PyType('structs.Point', True)
        py_types[('xcb', 'RECTANGLE')] = PyType('structs.Rectangle', True)
        py_out("extname = '%s'" % module.namespace.ext_xname)
        py_out()

def py_close(self):
    if ext_errors:
        py_out('class Error:')
        py_indent(+1)
        for error_name, error_code in sorted(ext_errors.items(), key=lambda v: v[1]):
            pyn = py_name(error_name)
            py_out('%s = %s' % (pyn, error_code))
        py_indent(-1)
        py_out()
    if not module.namespace.is_ext:
        return
    if (len(ext_events) + len(ext_ge_events)) > 0:
        py_out('class Event:')
        py_indent(+1)
        if len(ext_events) > 0:
            py_out('# Sub events.')
            for event_number, event_name in sorted(ext_events.items()):
                py_out('%s = %s' % (event_name, event_number))
        if len(ext_ge_events) > 0:
            py_out('# Generic events.')
            for event_number, event_name in sorted(ext_ge_events.items()):
                py_out('%s = %s' % (event_name, event_number))
        py_indent(-1)
        py_out()
    method_prefix = ''
    method_list = []
    for name, params in sorted(ext_requests.items()):
        init_fields, has_reply = params
        request_name = py_name(name)
        method_name = uncamel(request_name)
        if 'XInputExtension' == module.namespace.ext_xname:
            method_prefix = 'xinput_'
        else:
            method_prefix = module.namespace.prefix[-1] + '_'
        window_field_name = None
        param_list = []
        for field_name, field in init_fields:
            if ('xcb', 'WINDOW') == field.field_type:
                window_field_name = field_name
            elif 'opcode' == field_name:
                continue
            else:
                param_list.append(field_name)
        if window_field_name is not None:
            method_type = 'window'
        else:
            method_type = 'display'
        py_out("def %s(self, %s):" % (method_name, ', '.join(param_list)))
        py_indent(+1)
        if has_reply:
            py_out('return %s(' % request_name)
        else:
            py_out('%s(' % request_name)
        py_indent(+1)
        py_out('display=self.display,')
        py_out('opcode=self.display.get_extension_major(extname),')
        if window_field_name is not None:
            py_out('%s=self,' % window_field_name)
        for param in param_list:
            py_out('%s=%s,' % (param, param))
        py_indent(-1)
        py_out(')')
        py_indent(-1)
        py_out()
        method_list.append((method_type, method_name))
    py_out('def init(disp, info):')
    py_indent(+1)
    for method_type, method_name in method_list:
        py_out("disp.extension_add_method('%s', '%s%s', %s)" % (method_type,
                                                                method_prefix,
                                                                method_name,
                                                                method_name))
    for event_number, event_name in sorted(ext_events.items()):
        py_out("disp.extension_add_event(info.first_event + Event.%s, %sEventData)" % (event_name,
                                                                                       event_name))
    for event_number, event_name in sorted(ext_ge_events.items()):
        py_out("disp.ge_add_event_data(info.major_opcode, Event.%s, %sEventData)" % (event_name,
                                                                                     event_name))
    py_indent(-1)
    py_out()


def py_simple(self, name):
    assert name not in py_types, 'type already defined %s' % str(name)
    if ('xcb', 'xkb', 'STRING8') == name:
        # FIXME
        return
    pyn = py_name(name)
    pyt = py_types[self.name]
    py_types[name] = PyType(pyn, False)
    py_out('%s = %s' % (pyn, pyt.name))
    py_out()

def py_enum(self, name):
    pyn = py_name(name)
    py_out('class %s:' % pyn)
    py_indent(+1)
    for member_name, member_value in self.values:
        py_out('%s = %s' % (py_name(member_name), member_value))
    py_indent(-1)
    py_out()

def py_op(self, parent=None):
    if self is None:
        return '', ()
    if self.fixed_size():
        assert self.op is None
        assert self.lhs is None
        assert self.rhs is None
        assert self.lenfield_name is None
        return str(self.nmemb), ()
    if self.op is None:
        assert self.lhs is None
        assert self.rhs is None
        assert self.lenfield_name is not None
        name = uncamel(self.lenfield_name)
        if parent is None:
            return name, (name,)
        name = '%s.%s' % (parent, name)
        return name, ()
    if 'listelement-ref' == self.op:
        assert self.lhs is None
        assert self.rhs is None
        assert self.lenfield_name is None
        return 'n', ()
    result = []
    reflist = set()
    r, rl = py_op(self.lhs, parent=parent)
    result.append(r)
    reflist.update(rl)
    if 'popcount' == self.op:
        assert self.lhs is None
        assert self.rhs is not None
        assert self.lenfield_name == self.rhs.lenfield_name
        result.append('rq.popcount')
        result.append('(')
    elif 'sumof' == self.op:
        assert self.lhs is None
        assert self.lenfield_name is not None
        name = uncamel(self.lenfield_name)
        result.append('rq.sumof')
        result.extend(('(', name))
        reflist.add(name)
        if self.rhs is not None:
            result.append(', lambda n: ')
        parent = 'n'
    else:
        if '/' == self.op:
            op = '//'
        else:
            op = self.op
        result.insert(0, '(')
        if self.lhs is None:
            op = ' ' + op
        else:
            op = ' ' + op + ' '
        result.append(op)
    r, rl = py_op(self.rhs, parent=parent)
    reflist.update(rl)
    result.append(r)
    result.append(')')
    return ''.join(result), reflist

def py_fields(fields, fixups={}, context=None):
    if context is None:
        def collect_fields(field_list):
            all_field_list = []
            all_field_names = set()
            for field in field_list:
                if not field.wire:
                    continue
                if field.type.is_pad:
                    continue
                if field.field_name is not None:
                    field_name = uncamel(field.field_name)
                    assert field_name not in all_field_names, field_name
                    all_field_names.add(field_name)
                if field.type.is_switch:
                    if field.type.bitcases[0].type.is_bitcase:
                        # Bitcase switch: all sub-fields may be present,
                        # so no overlap in names allowed.
                        for subfield in field.type.bitcases:
                            subfield_list, subfield_names = collect_fields(subfield.type.fields)
                            assert subfield_names not in all_field_names
                            all_field_names.update(subfield_names)
                            all_field_list.extend(subfield_list)
                    else:
                        # Case switch: only one subfield will be present,
                        # overlapping names between them is allowed.
                        all_subfield_names = set()
                        for subfield in field.type.bitcases:
                            subfield_list, subfield_names = collect_fields(subfield.type.fields)
                            all_subfield_names.update(subfield_names)
                            all_field_list.extend(subfield_list)
                        assert all_subfield_names not in all_field_names
                        all_field_names.update(all_subfield_names)
                    continue
                if field.type.is_container:
                    continue
                all_field_list.append(field)
            return all_field_list, all_field_names
        all_fields, _ = collect_fields(fields)
        all_lenfield_names = {}
        needname_names = set()
        for field in all_fields:
            if field.type.fixed_size():
                continue
            assert hasattr(field.type, 'expr'), '%s %s' % (field.field_name, field.type.name)
            field_name = uncamel(field.field_name)
            ref_name = uncamel(field.type.expr.lenfield_name)
            op, reflist = py_op(field.type.expr)
            if len(reflist) > 1 or op != tuple(reflist)[0]:
                needname_names.update(reflist)
                continue
            if ref_name in all_lenfield_names:
                all_lenfield_names[ref_name].append(field_name)
            else:
                all_lenfield_names[ref_name] = [field_name]
    else:
        all_lenfield_names, needname_names = context
    init_fields = []
    skip_fields = []
    for n, field in enumerate(fields):
        if not field.wire:
            continue
        if n in skip_fields:
            continue
        # Padding.
        if field.type.is_pad:
            if field.type.fixed_size():
                py_out("rq.Pad(%u)," % field.type.nmemb)
            else:
                assert hasattr(field.type, 'align')
                py_out("rq.Align(%u)," % field.type.align)
            continue
        pad = 0
        if (n + 1) < len(fields):
            next_field = fields[n + 1]
            if next_field.type.is_pad and 4 == next_field.type.align:
                skip_fields.append(n + 1)
                pad = 1
        pyt = py_types.get(field.field_type, py_types.get(field.type.name, None))
        if (field.field_name, field.type.name) in fixups:
            assert 0 == pad
            new_pyn, fmt = fixups[(field.field_name, field.type.name)]
            out = fmt.format(field_type=pyt.name, field_size=field.type.size)
            if new_pyn is not None:
                init_fields.append((new_pyn, field))
            if out:
                py_out(out)
            continue
        field_name = uncamel(field.field_name)
        # Lengths.
        if field_name in all_lenfield_names:
            assert 0 == pad
            assert 1 == field.type.nmemb
            assert pyt.name in ('rq.Card8', 'rq.Card16', 'rq.Card32')
            target_name = all_lenfield_names[field_name]
            if 1 == len(target_name):
                target_name = target_name[0]
            else:
                target_name = tuple(target_name)
            if field_name in needname_names:
                field_name = "'%s'" % field_name
            else:
                field_name = 'None'
            py_out("rq.LengthOf(%s, %u, name=%s)," % (repr(target_name),
                                                      field.type.size,
                                                      field_name))
            # FIXME: add to init_fields if in needname_names?
            continue
        # Strings.
        if ('char',) == field.type.name:
            assert field.type.is_list
            if field.type.fixed_size():
                assert 0 == pad
                py_out("rq.FixedString('%s', %u)," % (field_name, field.type.nmemb))
            else:
                py_out("rq.String8('%s', pad=%u)," % (field_name, pad))
        # Switches.
        elif field.type.is_switch:
            assert 0 == pad
            is_bitcase = field.type.bitcases[0].type.is_bitcase
            py_out("rq.%sSwitch('%s', '%s', (" % (
                'Bitcase' if is_bitcase else 'Case',
                field.field_name,
                field.type.expr.lenfield_name),
            )
            py_indent(+1)
            for subfield in field.type.bitcases:
                assert subfield.type.is_container
                assert isinstance(subfield.type.expr, list)
                assert is_bitcase == subfield.type.is_bitcase
                value_list = []
                for expr in subfield.type.expr:
                    value_list.append('%s.%s' % (py_name(expr.lenfield_type.name),
                                                 py_name(expr.lenfield_name)))

                if is_bitcase:
                    py_out('(%s, (' % ' | '.join(value_list))
                else:
                    py_out('((%s,), (' % ', '.join(value_list))
                py_indent(+1)
                py_fields(subfield.type.fields, context=(all_lenfield_names, needname_names))
                py_indent(-1)
                py_out(')),')
            py_indent(-1)
            py_out(')),')
        # Lists.
        elif field.type.is_list:
            assert field.type.is_list
            if field.type.fixed_size():
                py_out("rq.FixedList('%s', %u, %s, pad=%u)," % (field_name,
                                                                field.type.nmemb,
                                                                pyt.name,
                                                                pad))
            else:
                assert hasattr(field.type, 'expr')
                op, reflist = py_op(field.type.expr)
                assert reflist
                if len(reflist) > 1 or op != tuple(reflist)[0]:
                    calc_length = 'lambda %s: %s' % (
                        ', '.join(sorted(reflist)), op
                    )
                else:
                    calc_length = 'None'
                py_out("rq.List('%s', %s, pad=%u, calc_length=%s)," % (
                    field_name, pyt.name, pad, calc_length,
                ))
        elif pyt.is_complex:
            assert 0 == pad
            assert 1 == field.type.nmemb
            assert not field.type.is_simple
            py_out("rq.Object('%s', %s)," % (field_name, pyt.name))
        else:
            assert 0 == pad
            assert 1 == field.type.nmemb
            assert not field.type.is_container
            py_out("%s('%s')," % (pyt.name, field_name))
        init_fields.append((field_name, field))
    return init_fields

def py_struct(self, name):
    if name is not None:
        pyn = py_name(name)
        py_out('%s = rq.Struct(' % pyn)
    else:
        pyn = '???'
        py_out('rq.Struct(', indent=False)
    py_indent(+1)
    py_fields(self.fields)
    py_indent(-1)
    if name is not None:
        py_out(')')
        py_out()
        py_types[name] = PyType(pyn, True)
    else:
        py_out(')', endl=False)

def py_union(self, name):
    pyn = py_name(name)
    py_out('%s = rq.Union(' % pyn)
    py_indent(+1)
    py_fields(self.fields)
    py_indent(-1)
    py_out(')')
    py_out()
    py_types[name] = PyType(pyn, True)

def py_request(self, name):
    pyn = py_name(name)
    if self.reply:
        request_class = 'rq.ReplyRequest'
    else:
        request_class = 'rq.Request'
    py_out('class %s(%s):' % (pyn, request_class))
    py_out()
    py_indent(+1)
    py_out('_request = rq.Struct(')
    py_indent(+1)
    fixups = {
        ('major_opcode', ('uint8_t',)): ('opcode', "{field_type}('opcode'),"),
        ('minor_opcode', ('uint8_t',)): (None    , 'rq.Opcode(%s),' % self.opcode),
        ('length',      ('uint16_t',)): (None    , 'rq.RequestLength(),'),
    }
    init_fields = py_fields(self.fields, fixups)
    py_indent(-1)
    py_out(')')
    py_out()
    if self.reply:
        py_out('_reply = rq.Struct(')
        py_indent(+1)
        fixups = {
            ('response_type', ('uint8_t',)): (None, 'rq.ReplyCode(),'),
            ('sequence',     ('uint16_t',)): (None, "{field_type}('sequence_number'),"),
            ('length',       ('uint32_t',)): (None, 'rq.ReplyLength(),'),
        }
        py_fields(self.reply.fields, fixups)
        py_indent(-1)
        py_out(')')
        py_out()
    py_indent(-1)
    assert name not in ext_requests
    ext_requests[name] = (init_fields, not not self.reply)

def py_event(self, name):
    pyn = py_name(name) + 'EventData'
    if self.is_ge_event:
        assert [(f.field_name, f.type.name) for f in self.fields[0:5]] == [
            ('response_type', ('uint8_t' , )),
            ('extension'    , ('uint8_t' , )),
            ('sequence'     , ('uint16_t', )),
            ('length'       , ('uint32_t', )),
            ('event_type'   , ('uint16_t', )),
        ]
        py_out('%s = rq.Struct(' % pyn)
        py_indent(+1)
        py_fields(self.fields[5:])
        py_indent(-1)
        py_out(')')
        py_out()
    else:
        py_out('class %s(rq.Event):' % pyn)
        py_indent(+1)
        py_out('_code = None')
        py_out('_fields = rq.Struct(')
        py_indent(+1)
        py_fields(self.fields)
        py_indent(-1)
        py_out(')')
        py_indent(-1)
        py_out()
    pyn = py_name(name)
    opcode = int(self.opcodes[name])
    if self.is_ge_event:
        events_dict = ext_ge_events
    else:
        events_dict = ext_events
    assert opcode not in events_dict
    events_dict[opcode] = pyn

def py_error(self, name):
    ext_errors.update(self.opcodes)


output = {'open'    : py_open,
          'close'   : py_close,
          'simple'  : py_simple,
          'enum'    : py_enum,
          'struct'  : py_struct,
          'union'   : py_union,
          'request' : py_request,
          'event'   : py_event,
          'error'   : py_error,
          }

from xcbgen.state import Module
from xcbgen.xtypes import *


module = Module(sys.argv[1], output)
module.register()
module.resolve()
module.generate()