#!/usr/bin/python3

#

# check-kabi - Red Hat kABI reference checking tool

#

# We use this script to check against reference Module.kabi files.

#

# Author: Jon Masters <jcm@redhat.com>

# Copyright (C) 2007-2009 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.

# 2009/08/15 - Updated for use in RHEL6.

# 2007/06/13 - Initial rewrite in python by Jon Masters.

__author__ = "Jon Masters <jcm@redhat.com>"

__version__ = "2.0"

__date__ = "2009/08/15"

__copyright__ = "Copyright (C) 2007-2009 Red Hat, Inc"

__license__ = "GPL"

import getopt

import string

import sys

true = 1

false = 0

def load_symvers(symvers, filename):

    """Load a 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, type, *ns = in_line.split()

        ns = ns[0] if ns else None

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

def load_kabi(kabi, filename):

    """Load a Module.kabi file."""

    kabi_file = open(filename, "r")

    while true:

        in_line = kabi_file.readline()

        if in_line == "":

            break

        if in_line == "\n":

            continue

        checksum, symbol, directory, type, *ns = in_line.split()

        ns = ns[0] if ns else None

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

def check_kabi(symvers, kabi):

    """Check Module.kabi and Module.symvers files."""

    fail = 0

    warn = 0

    changed_symbols = []

    moved_symbols = []

    ns_symbols = []

    for symbol in kabi:

        abi_hash, abi_sym, abi_dir, abi_type, *abi_ns = kabi[symbol].split()

        abi_ns = abi_ns[0] if abi_ns else None

        if symbol in symvers:

            sym_hash, sym_sym, sym_dir, sym_type, *sym_ns = symvers[symbol].split()

            sym_ns = sym_ns[0] if sym_ns else None

            if abi_hash != sym_hash:

                fail = 1

                changed_symbols.append(symbol)

            if abi_dir != sym_dir:

                warn = 1

                moved_symbols.append(symbol)

            if abi_ns != sym_ns:

                warn = 1

                ns_symbols.append(symbol)

        else:

            fail = 1

            changed_symbols.append(symbol)

    if fail:

        print("*** ERROR - ABI BREAKAGE WAS DETECTED ***")

        print("")

        print("The following symbols have been changed (this will cause an ABI breakage):")

        print("")

        for symbol in changed_symbols:

            print(symbol)

        print("")

    if warn:

        print("*** WARNING - ABI SYMBOLS MOVED ***")

        if moved_symbols:

            print("")

            print("The following symbols moved (typically caused by moving a symbol from being")

            print("provided by the kernel vmlinux out to a loadable module):")

            print("")

            for symbol in moved_symbols:

                print(symbol)

            print("")

        if ns_symbols:

            print("")

            print("The following symbols changed symbol namespaces:")

            print("")

            for symbol in ns_symbols:

                print(symbol)

            print("")

    """Halt the build, if we got errors and/or warnings. In either case,

       double-checkig is required to avoid introducing / concealing

       KABI inconsistencies."""

    if fail or warn:

        sys.exit(1)

    sys.exit(0)

def usage():

    print("""

check-kabi: check Module.kabi and Module.symvers files.

    check-kabi [ -k Module.kabi ] [ -s Module.symvers ]

""")

if __name__ == "__main__":

    symvers_file = ""

    kabi_file = ""

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

    for o, v in opts:

        if o == "-s":

            symvers_file = v

        if o == "-h":

            usage()

            sys.exit(0)

        if o == "-k":

            kabi_file = v

    if (symvers_file == "") or (kabi_file == ""):

        usage()

        sys.exit(1)

    symvers = {}

    kabi = {}

    load_symvers(symvers, symvers_file)

    load_kabi(kabi, kabi_file)

    check_kabi(symvers, kabi)