1"""This script generates a Python codec module from a Windows Code Page.
2
3It uses the function MultiByteToWideChar to generate a decoding table.
4"""
5
6import ctypes
7from ctypes import wintypes
8from gencodec import codegen
9import unicodedata
10
11def genwinmap(codepage):
12    MultiByteToWideChar = ctypes.windll.kernel32.MultiByteToWideChar
13    MultiByteToWideChar.argtypes = [wintypes.UINT, wintypes.DWORD,
14                                    wintypes.LPCSTR, ctypes.c_int,
15                                    wintypes.LPWSTR, ctypes.c_int]
16    MultiByteToWideChar.restype = ctypes.c_int
17
18    enc2uni = {}
19
20    for i in range(32) + [127]:
21        enc2uni[i] = (i, 'CONTROL CHARACTER')
22
23    for i in range(256):
24        buf = ctypes.create_unicode_buffer(2)
25        ret = MultiByteToWideChar(
26            codepage, 0,
27            chr(i), 1,
28            buf, 2)
29        assert ret == 1, "invalid code page"
30        assert buf[1] == '\x00'
31        try:
32            name = unicodedata.name(buf[0])
33        except ValueError:
34            try:
35                name = enc2uni[i][1]
36            except KeyError:
37                name = ''
38
39        enc2uni[i] = (ord(buf[0]), name)
40
41    return enc2uni
42
43def genwincodec(codepage):
44    import platform
45    map = genwinmap(codepage)
46    encodingname = 'cp%d' % codepage
47    code = codegen("", map, encodingname)
48    # Replace first lines with our own docstring
49    code = '''\
50"""Python Character Mapping Codec %s generated on Windows:
51%s with the command:
52  python Tools/unicode/genwincodec.py %s
53"""#"
54''' % (encodingname, ' '.join(platform.win32_ver()), codepage
55      ) + code.split('"""#"', 1)[1]
56
57    print code
58
59if __name__ == '__main__':
60    import sys
61    genwincodec(int(sys.argv[1]))
62