#!/usr/bin/env python2
import os
import sys
import subprocess
import re

runtime_libs = ['libc',
                'libdl',
                'libm',
                'libpthread',
                'libutil',
                'libnss_dns',
                'libresolv',
                'librt']


def parse_libs(bin_path):
  ldd_out = subprocess.check_output(['ldd', bin_path])
  lib_list = []
  for line in ldd_out.splitlines():
    match = re.match(r'\t(.*) => (.*) \(0x', line)
    if match and match.group(1) and match.group(2):
      name_match = re.match(r'([\w\d]*)(-*)([\w\d]*)(\.*)(.*)', match.group(1))
      if name_match:
        lib_name = name_match.group(1)

        # library can be formatted as libxxx-xxx.so which is invalid format in
        # the manifest, so reformat to libxxx_xxx as the option key
        if name_match.group(2) == '-' and name_match.group(3):
          lib_name += '_' + name_match.group(3)

        if lib_name not in runtime_libs:
          lib_list.append((lib_name, match.group(2)))

  return lib_list


def make_executable(path):
  mode = os.stat(path).st_mode
  mode |= (mode & 0o444) >> 2    # copy R bits to X
  os.chmod(path, mode)


def gen_manifest(app_name, bin_name, g_path):
  m_path = g_path + '/LibOS/shim/test/apps/' + app_name + '/' + app_name + '.' + 'manifest'
  print('generating manifest: ' + m_path)

  mf = open(m_path, 'w')
  make_executable(m_path)

  mf.write('#!' + g_path + '/Runtime/pal_loader\n')
  mf.write('loader.preload = file:../../../../../Runtime/libsysdb.so\n')

  # Get path of binary
  bin_path = subprocess.check_output(['which', bin_name]).strip()
  mf.write('loader.exec = file:' + bin_path + '\n')
  mf.write('loader.execname = ' + bin_name + '\n')
  mf.write('loader.env.LD_LIBRARY_PATH = /graphene:/graphene/resolv:/host:/usr/local/lib:/usr/lib:/usr/lib/x86_64-linux-gnu')

  if 'LD_LIBRARY_PATH' in os.environ and os.environ['LD_LIBRARY_PATH']:
    mf.write(':' + os.environ['LD_LIBRARY_PATH'])
  mf.write('\n')

  mf.write('loader.env.PATH = /usr/local/bin:/usr/bin:/bin\n' +
           'loader.env.USERNAME =\n' +
           'loader.env.PWD =\n' +
           'loader.debug_type = none\n')
  mf.write('\n')

  # File system setting
  mf.write('fs.mount.lib1.type = chroot\n' +
           'fs.mount.lib1.path = /graphene\n' +
           'fs.mount.lib1.uri = file:../../../../../Runtime\n\n')

  mf.write('fs.mount.lib2.type = chroot\n' +
           'fs.mount.lib2.path = /host\n' +
           'fs.mount.lib2.uri = file:/lib/x86_64-linux-gnu\n\n')

  mf.write('fs.mount.bin.type = chroot\n' +
           'fs.mount.bin.path = /bin\n' +
           'fs.mount.bin.uri = file:/bin\n\n')

  mf.write('fs.mount.usr.type = chroot\n' +
           'fs.mount.usr.path = /usr\n' +
           'fs.mount.usr.uri = file:/usr\n\n')

  mf.write('fs.mount.etc.type = chroot\n' +
           'fs.mount.etc.path = /etc\n' +
           'fs.mount.etc.uri = file:\n\n')

  mf.write('fs.mount.opt.type = chroot\n' +
           'fs.mount.opt.path = /opt\n' +
           'fs.mount.opt.uri = file:\n\n')

  # Set Dependent Libraries
  mf.write('sgx.trusted_files.ld = file:../../../../../Runtime/ld-linux-x86-64.so.2\n' +
           'sgx.trusted_files.libc = file:../../../../../Runtime/libc.so.6\n' +
           'sgx.trusted_files.libdl = file:../../../../../Runtime/libdl.so.2\n' +
           'sgx.trusted_files.libm = file:../../../../../Runtime/libm.so.6\n' +
           'sgx.trusted_files.libpthread = file:../../../../../Runtime/libpthread.so.0\n' +
           'sgx.trusted_files.libutil = file:../../../../../Runtime/libutil.so.1\n' +
           'sgx.trusted_files.libnss_dns = file:../../../../../Runtime/libnss_dns.so.2\n' +
           'sgx.trusted_files.libresolv = file:../../../../../Runtime/libresolv.so.2\n' +
           'sgx.trusted_files.librt = file:../../../../../Runtime/librt.so.1\n')

  lib_list = parse_libs(bin_path)
  for lib_name, lib_path in lib_list:
    print('lib name: ' + lib_name)
    print('lib path: ' + lib_path)
    mf.write('sgx.trusted_files.' + lib_name + ' = file:' + lib_path + '\n')
  mf.write('\n')

  mf.close()


if __name__ == '__main__':
  if len(sys.argv) != 4:
    print('Usage: gen_manifest [application name] [actual binary name] [path to graphene]')
    print('  e.g. gen_manifest apache httpd /home/me/graphene')
    exit(1)

  app_name = sys.argv[1]
  bin_name = sys.argv[2]
  g_path = sys.argv[3]

  gen_manifest(app_name, bin_name, g_path)