from __future__ import division, absolute_import, print_function

import re

import sys

import os

import subprocess

__doc__ = """This module generates a DEF file from the symbols in

an MSVC-compiled DLL import library.  It correctly discriminates between

data and functions.  The data is collected from the output of the program

nm(1).

Usage:

    python lib2def.py [libname.lib] [output.def]

or

    python lib2def.py [libname.lib] > output.def

libname.lib defaults to python<py_ver>.lib and output.def defaults to stdout

Author: Robert Kern <kernr@mail.ncifcrf.gov>

Last Update: April 30, 1999

"""

__version__ = '0.1a'

py_ver = "%d%d" % tuple(sys.version_info[:2])

DEFAULT_NM = 'nm -Cs'

DEF_HEADER = """LIBRARY         python%s.dll

;CODE           PRELOAD MOVEABLE DISCARDABLE

;DATA           PRELOAD SINGLE

EXPORTS

""" % py_ver

# the header of the DEF file

FUNC_RE = re.compile(r"^(.*) in python%s\.dll" % py_ver, re.MULTILINE)

DATA_RE = re.compile(r"^_imp__(.*) in python%s\.dll" % py_ver, re.MULTILINE)

def parse_cmd():

    """Parses the command-line arguments.

libfile, deffile = parse_cmd()"""

    if len(sys.argv) == 3:

        if sys.argv[1][-4:] == '.lib' and sys.argv[2][-4:] == '.def':

            libfile, deffile = sys.argv[1:]

        elif sys.argv[1][-4:] == '.def' and sys.argv[2][-4:] == '.lib':

            deffile, libfile = sys.argv[1:]

        else:

            print("I'm assuming that your first argument is the library")

            print("and the second is the DEF file.")

    elif len(sys.argv) == 2:

        if sys.argv[1][-4:] == '.def':

            deffile = sys.argv[1]

            libfile = 'python%s.lib' % py_ver

        elif sys.argv[1][-4:] == '.lib':

            deffile = None

            libfile = sys.argv[1]

    else:

        libfile = 'python%s.lib' % py_ver

        deffile = None

    return libfile, deffile

def getnm(nm_cmd = ['nm', '-Cs', 'python%s.lib' % py_ver]):

    """Returns the output of nm_cmd via a pipe.

nm_output = getnam(nm_cmd = 'nm -Cs py_lib')"""

    f = subprocess.Popen(nm_cmd, shell=True, stdout=subprocess.PIPE, universal_newlines=True)

    nm_output = f.stdout.read()

    f.stdout.close()

    return nm_output

def parse_nm(nm_output):

    """Returns a tuple of lists: dlist for the list of data

symbols and flist for the list of function symbols.

dlist, flist = parse_nm(nm_output)"""

    data = DATA_RE.findall(nm_output)

    func = FUNC_RE.findall(nm_output)

    flist = []

    for sym in data:

        if sym in func and (sym[:2] == 'Py' or sym[:3] == '_Py' or sym[:4] == 'init'):

            flist.append(sym)

    dlist = []

    for sym in data:

        if sym not in flist and (sym[:2] == 'Py' or sym[:3] == '_Py'):

            dlist.append(sym)

    dlist.sort()

    flist.sort()

    return dlist, flist

def output_def(dlist, flist, header, file = sys.stdout):

    """Outputs the final DEF file to a file defaulting to stdout.

output_def(dlist, flist, header, file = sys.stdout)"""

    for data_sym in dlist:

        header = header + '\t%s DATA\n' % data_sym

    header = header + '\n' # blank line

    for func_sym in flist:

        header = header + '\t%s\n' % func_sym

    file.write(header)

if __name__ == '__main__':

    libfile, deffile = parse_cmd()

    if deffile is None:

        deffile = sys.stdout

    else:

        deffile = open(deffile, 'w')

    nm_cmd = [str(DEFAULT_NM), str(libfile)]

    nm_output = getnm(nm_cmd)

    dlist, flist = parse_nm(nm_output)

    output_def(dlist, flist, DEF_HEADER, deffile)