#!/usr/bin/env python
# -*- coding: utf-8 -*-
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals

import argparse
import re
import subprocess
import tempfile

import gdb

import pwndbg.commands
import pwndbg.vmmap

parser = argparse.ArgumentParser(description="Dump ROP gadgets with Jon Salwan's ROPgadget tool.",
                                epilog="Example: rop --grep 'pop rdi' -- --nojop")
parser.add_argument('--grep', type=str,
                    help='String to grep the output for')
parser.add_argument('argument', nargs='*', type=str,
                    help='Arguments to pass to ROPgadget')

@pwndbg.commands.ArgparsedCommand(parser)
def rop(grep, argument):
    with tempfile.NamedTemporaryFile() as corefile:

        # If the process is running, dump a corefile so we get actual addresses.
        if pwndbg.proc.alive:
            filename = corefile.name
            gdb.execute('gcore %s' % filename)
        else:
            filename = pwndbg.proc.exe

        # If no binary was specified, we can't do anything
        if not filename:
            print("No file to get gadgets from")
            return

        # Build up the command line to run
        cmd = ['ROPgadget',
               '--binary',
               filename]
        cmd += argument

        try:
            io = subprocess.Popen(cmd, stdout=subprocess.PIPE)
        except Exception:
            print("Could not run ROPgadget.  Please ensure it's installed and in $PATH.")

        (stdout, stderr) = io.communicate()

        stdout = stdout.decode('latin-1')

        if not grep:
            print(stdout)
            return

        for line in stdout.splitlines():
            if re.search(grep, line):
                print(line)

@pwndbg.commands.Command
def ropgadget(*a):
    return rop(*a)
