#  Copyright (c) 2007-2012 Red Hat, Inc. <http://www.redhat.com>
#  This file is part of GlusterFS.
#
#  This file is licensed to you under your choice of the GNU Lesser
#  General Public License, version 3 or any later version (LGPLv3 or
#  later), or the GNU General Public License, version 2 (GPLv2), in all
#  cases as published by the Free Software Foundation.

from ctypes import *
from glustertypes import *

libc = CDLL("libc.so.6")
calloc = libc.calloc
calloc.argtypes = [c_int, c_int]
calloc.restype = c_void_p

# TODO: Can these be done in C somehow?
def stack_wind(frame, rfn, obj, fn, *params):
    """Frame is a frame object"""
    _new = cast(calloc(1, sizeof(call_frame_t)), POINTER(call_frame_t))
    _new[0].root = frame.root
    _new[0].next = frame.root[0].frames.next
    _new[0].prev = pointer(frame.root[0].frames)
    if frame.root[0].frames.next:
        frame.root[0].frames.next[0].prev = _new
    frame.root[0].frames.next = _new
    _new[0].this = obj
    # TODO: Type checking like tmp_cbk?
    _new[0].ret = rfn
    _new[0].parent = pointer(frame)
    _new[0].cookie = cast(_new, c_void_p)
    # TODO: Initialize lock
    #_new.lock.init()
    frame.ref_count += 1
    fn(_new, obj, *params)

def stack_unwind(frame, *params):
    """Frame is a frame object"""
    fn = frame[0].ret
    parent = frame[0].parent[0]
    parent.ref_count -= 1

    op_ret = params[0]
    op_err = params[1]
    params = params[2:]
    fn(parent, call_frame_t.from_address(frame[0].cookie), parent.this,
            op_ret, op_err, *params)