Exemplo n.º 1
0
def init_parser():
    """Set up the parser with the grammar to be recognized.
    """
    # CORE
    digit = h.ch_range(0x30, 0x39)
    alpha = h.choice(h.ch_range(0x41, 0x5a), h.ch_range(0x61, 0x7a))
    space = h.in_(b" \t\n\r\f\v")

    # AUX.
    plus = h.ch(b'+')
    slash = h.ch(b'/')
    equals = h.ch(b'=')

    bsfdig = h.choice(alpha, digit, plus, slash)
    bsfdig_4bit = h.in_(b"AEIMQUYcgkosw048")
    bsfdig_2bit = h.in_(b"AQgw")
    base64_3 = h.repeat_n(bsfdig, 4)
    base64_2 = h.sequence(bsfdig, bsfdig, bsfdig_4bit, equals)
    base64_1 = h.sequence(bsfdig, bsfdig_2bit, equals, equals)
    base64 = h.action(
        h.sequence(h.many(base64_3), h.optional(h.choice(base64_2, base64_1))),
        act_base64)

    # TODO This is not quite the same as the C example, with uses act_ignore.
    #      But I can't get hammer to filter any value returned by act_ignore.
    ws = h.ignore(h.many(space))
    document = h.action(h.sequence(ws, base64, ws, h.end_p()), act_document)

    # BUG sometimes inputs that should just don't parse.
    # It *seemed* to happen mostly with things like "bbbbaaaaBA==".
    # Using less actions seemed to make it less likely.

    return document
Exemplo n.º 2
0
def init_parser():
    """Set up the parser with the grammar to be recognized.
    """
    # CORE
    digit   = h.ch_range(0x30, 0x39)
    alpha   = h.choice(h.ch_range(0x41, 0x5a), h.ch_range(0x61, 0x7a))
    space   = h.in_(" \t\n\r\f\v")

    # AUX.
    plus    = h.ch('+')
    slash   = h.ch('/')
    equals  = h.ch('=')

    bsfdig      = h.choice(alpha, digit, plus, slash)
    bsfdig_4bit = h.in_("AEIMQUYcgkosw048")
    bsfdig_2bit = h.in_("AQgw")
    base64_3    = h.repeat_n(bsfdig, 4)
    base64_2    = h.sequence(bsfdig, bsfdig, bsfdig_4bit, equals)
    base64_1    = h.sequence(bsfdig, bsfdig_2bit, equals, equals)
    base64      = h.action(h.sequence(h.many(base64_3),
                                      h.optional(h.choice(base64_2,
                                                          base64_1))),
                           act_base64)

    # TODO This is not quite the same as the C example, with uses act_ignore.
    #      But I can't get hammer to filter any value returned by act_ignore.
    ws          = h.ignore(h.many(space))
    document    = h.action(h.sequence(ws, base64, ws, h.end_p()),
                           act_document)

    # BUG sometimes inputs that should just don't parse.
    # It *seemed* to happen mostly with things like "bbbbaaaaBA==".
    # Using less actions seemed to make it less likely.

    return document
Exemplo n.º 3
0
def init_parser():
    """Return a parser with the grammar to be recognized.
    """
    # CORE

    # This is a direct translation of the  C example. In C the literal 0x30
    # is interchangable with the char literal '0' (note the single quotes).
    # This is not the case in Python.
    
    # TODO In the interests of being more Pythonic settle on either string
    #      literals, or integers
    digit   = h.ch_range(0x30, 0x39)
    alpha   = h.choice(h.ch_range(0x41, 0x5a), h.ch_range(0x61, 0x7a))
    space   = h.in_(" \t\n\r\f\v")

    # AUX.
    plus    = h.ch('+')
    slash   = h.ch('/')
    equals  = h.action(h.ch('='), act_equals)

    bsfdig      = h.action(h.choice(alpha, digit, plus, slash), act_bsfdig)
    bsfdig_4bit = h.action(h.in_("AEIMQUYcgkosw048"), act_bsfdig_4bit)
    bsfdig_2bit = h.action(h.in_("AQgw"), act_bsfdig_2bit)
    base64_3    = h.action(h.repeat_n(bsfdig, 4), act_base64_3)
    base64_2    = h.action(h.sequence(bsfdig, bsfdig, bsfdig_4bit, equals),
                           act_base64_2)
    base64_1    = h.action(h.sequence(bsfdig, bsfdig_2bit, equals, equals),
                           act_base64_1)
    base64      = h.action(h.sequence(h.many(base64_3),
                                      h.optional(h.choice(base64_2,
                                                          base64_1))),
                           act_base64)

    # TODO This is not quite the same as the C example, with uses act_ignore.
    #      But I can't get hammer to filter any value returned by act_ignore.
    ws          = h.ignore(h.many(space))
    document    = h.action(h.sequence(ws, base64, ws, h.end_p()),
                           act_document)

    # BUG sometimes inputs that should just don't parse.
    # It *seemed* to happen mostly with things like "bbbbaaaaBA==".
    # Using less actions seemed to make it less likely.

    return document
Exemplo n.º 4
0
 def setUpClass(cls):
     cls.parser = h.sequence(h.ch("a"), h.ignore(h.ch("b")), h.ch("c"))
Exemplo n.º 5
0
 def setUpClass(cls):
     cls.parser = h.sequence(h.ch(b"a"), h.ignore(h.ch(b"b")), h.ch(b"c"))