#!/usr/bin/env python

# Copyright (c) 2020 Trail of Bits, Inc.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import os.path
import subprocess

def usage(executable):
    print "Usage:"
    print "{} <header file> [header file] [header file] ...".format(executable)

def check_prerequisites():
    if not os.path.isdir("cparser"):
        print "[+] cparser project not found, cloning cparser"
        return subprocess.call(["git", "clone", "https://github.com/pgoodman/cparser.git"])
    return 0

def process_single_file(filename):
    '''given a filename, runs that file the the preprocessor, post processor, and std def generator. 
    Returns the text of the resulting std def'''
    cc_subproc = subprocess.Popen(["cc", "-E", filename], stdout=subprocess.PIPE)
    post_proc = subprocess.Popen(["python", "cparser/post_process_header.py"], stdin=cc_subproc.stdout, stdout=subprocess.PIPE)
    make_def_proc = subprocess.Popen(["python", "cparser/make_std_defs.py"], stdin=post_proc.stdout, stdout=subprocess.PIPE)
    cc_subproc.stdout.close()
    post_proc.stdout.close()
    make_def_stdout = make_def_proc.communicate()[0]
    return make_def_stdout

def main(args):
    if len(args) == 1:
        usage(args[0])
        return 1
    if 0 != check_prerequisites():
        print "error checking or installing prerequisites, aborting"
        return 2
    for filename in args[1:]:
        if os.path.isfile(filename):
            print process_single_file(filename)
    return 0

if __name__=='__main__':
    import sys
    sys.exit(main(sys.argv))