#!/usr/bin/python3
#
# make-kabi - Red Hat kABI reference module generation tool
#
# We use this script to generate reference Module.kabi files.
# or add reference info to separate kabi files.
#
# Author: Jon Masters <jcm@redhat.com>
# Copyright (C) 2007 Red Hat, Inc.
#
# This software may be freely redistributed under the terms of the GNU
# General Public License (GPL).

# Changelog:
#
# 2018/06/01 - Update for python3 by Petr Oros.
# 2014/10/05 - Update for new kabi structure by Petr Oros.
# 2007/06/13 - Initial rewrite in python by Jon Masters.

__author__ = "Jon Masters <jcm@redhat.com>"
__version__ = "2.0"
__date__ = "2014/10/05"
__copyright__ = "Copyright (C) 2007 Red Hat, Inc"
__license__ = "GPL"

import getopt
import os
import re
import string
import sys

true = 1
false = 0


def load_symvers(symvers, filename):
    """Load a reference Module.symvers file."""

    symvers_file = open(filename, "r")

    while true:
        in_line = symvers_file.readline()
        if in_line == "":
            break
        if in_line == "\n":
            continue
        checksum, symbol, directory, ctype = in_line.split()

        symvers[symbol] = in_line[0:-1]


def load_stablelist(stablelist, order, filename):
    if os.path.isfile(filename):
        load_stablelist_file(stablelist, order, filename)
    else:
        load_stablelist_dir(stablelist, order, filename)


def load_stablelist_file(stablelist, order, filename):
    """Load a reference stablelist file."""

    stablelist_file = open(filename, "r")

    while true:
        in_line = stablelist_file.readline()
        if in_line == "":
            break
        if in_line == "\n":
            continue
        in_line.split()
        if in_line[0] == "[":
            continue
        symbol = in_line[1:-1]

        stablelist[symbol] = []
        order.append(symbol)

    order.sort()


def load_stablelist_dir(stablelist, order, dirname):
    """Load a reference stablelist directory."""

    for symbol in os.listdir(dirname):
        kabi_file = open(dirname + "/" + symbol, "r")
        line = []
        # store version metadata
        line.append(kabi_file.readline())
        # store content ( no empty line is bad state )
        line.append(kabi_file.readline())
        kabi_file.close()
        if re.match("#[0-9]+-[0-9]+", line[0]):
            print("Symbol {} is currently removed, ignoring".format(symbol))
            continue
        stablelist[symbol] = line
        order.append(symbol)

    order.sort()


def make_kabi_file(filename, symvers, order):
    """Munge together stablelist and Module.symvers file."""

    if os.path.isfile(filename):
        print("{} already exists".format(filename))
        sys.exit(1)

    kabi_file = open(filename, "w")

    for symbol in order:
        if symbol in symvers:
            kabi_file.write(symvers[symbol] + "\n")

    kabi_file.close()


def make_kabi_dir(dirname, symvers, stablelist):
    """Munge together stablelist and Module.symvers file."""

    current_dir = os.getcwd()
    os.chdir(dirname)

    for symbol in stablelist:
        if symbol in symvers:
            kabi_file = open(symbol, "w")
            kabi_file.write(stablelist[symbol][0])
            kabi_file.write(symvers[symbol] + "\n")
            kabi_file.close()

    os.chdir(current_dir)


def usage():
    print("""make-kabi: process Module.symvers into reference Module.kabi output file/directory using
           the kabi stablelist provided as a set of symbols to filer on.

    make-kabi [ -k Module.kabi or -d (kabi-module dir) ] [ -s Module.symvers ] [ -w kabi_stablelist ]

    examples:
        add checksums to files into kabi-module/kabi_x86_64/
            make-kabi -s Module.symvers -w kabi-module/kabi_x86_64/ -d

        create Module.kabi ( old style ) witch checksums
            make-kabi -s Module.symvers -w kabi-module/kabi_x86_64/ -k Module.kabi""")


if __name__ == "__main__":

    stablelist_source = ""
    symvers_file = ""
    kabi_output = ""
    kabi_file = true

    opts, args = getopt.getopt(sys.argv[1:], 'hk:s:w:d')

    for o, v in opts:
        if o == "-s":
            symvers_file = v
        if o == "-h":
            usage()
            sys.exit(0)
        if o == "-k":
            kabi_output = v
            kabi_file = true
        if o == "-d":
            kabi_file = false
        if o == "-w":
            stablelist_source = v

    if (stablelist_source == "") or (symvers_file == "") or (kabi_output == "" and kabi_file):
        usage()
        sys.exit(1)

    symvers = {}
    stablelist = {}
    stablelist_order = []

    load_symvers(symvers, symvers_file)
    load_stablelist(stablelist, stablelist_order, stablelist_source)
    if kabi_file:
        make_kabi_file(kabi_output, symvers, stablelist_order)
    else:
        make_kabi_dir(stablelist_source, symvers, stablelist)