# -*- coding: utf-8 -*-

"""

    mem

    ~~~

    :copyright: 2010 by Henri Tuhola <henri.tuhola@gmail.com>

    This works only on 32bit python.

"""

from ctypes import CDLL, memmove, cast

from core import pass0, pass1

from mmap import MAP_ANONYMOUS, MAP_PRIVATE, PROT_EXEC, PROT_READ, PROT_WRITE

libc = CDLL('libc.so.6')

PROT_ALL = PROT_EXEC | PROT_READ | PROT_WRITE

MAP_PROGRAM = MAP_ANONYMOUS | MAP_PRIVATE

class ProgramInMemory(object):

    def __init__(self, assembly, functype):

        size = pass0([assembly], 0)

        address = libc.mmap(None, size, PROT_ALL, MAP_PROGRAM, 0, 0)

        pass0([assembly], address)

        memmove(address, pass1([assembly]), size)

        self.address = address

        self.size = size

        self.function = cast(address, functype)

    def discard(self):

        libc.munmap(self.address, self.size)

    def __call__(self, *args):

        return self.function(*args)

if __name__ == '__main__':

    from g386 import X86, Assembly, Deref, r0,r1,r2,r3,r4,r5,r6,r7

    from ctypes import CFUNCTYPE, c_int

    regs = [r0,r1,r2,r3,r6,r7]

    x = little_function = X86(regs)

    x.move(r0, x.add(Deref(r4, 4), 50))

    x.ret()

    mem = ProgramInMemory(little_function, CFUNCTYPE(c_int, c_int))

    print mem(500)