#! /usr/bin/env python3
# Copyright 2024 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import argparse
import pathlib


def _generate(arch, hwasan, asan, env):
    ret = """\
#!/system/bin/sh
"""

    if hwasan:
        # https://developer.android.com/ndk/guides/hwasan#wrapsh
        ret += """
# import options file
_HWASAN_OPTIONS=$(cat /data/local/tmp/hwasan.options 2> /dev/null || true)

log -t cr_wrap.sh -- "Launching with HWASAN enabled."
"""
        env['HWASAN_OPTIONS'] = '$_HWASAN_OPTIONS'
        env['LD_HWASAN'] = '1'

    if asan:
        # https://github.com/google/sanitizers/wiki/AddressSanitizerOnAndroid/01f8df1ac1a447a8475cdfcb03e8b13140042dbd#running-with-wrapsh-recommended
        ret += f"""
HERE="$(cd "$(dirname "$0")" && pwd)"
    # Options suggested by wiki docs:
    _ASAN_OPTIONS="log_to_syslog=true,allow_user_segv_handler=1"
    # Chromium-specific option (supposedly for graphics drivers):
    _ASAN_OPTIONS="$_ASAN_OPTIONS,strict_memcmp=0,use_sigaltstack=1"
    _LD_PRELOAD="$(dirname "$(dirname "$HERE")")/base.apk!/lib/{arch}/libclang_rt.asan-{arch}-android.so"

    log -t cr_wrap.sh -- "Launching with ASAN enabled."
"""
        env['LD_PRELOAD'] = '$_LD_PRELOAD'
        env['ASAN_OPTIONS'] = '$_ASAN_OPTIONS'

    ret += 'log -t cr_wrap.sh -- "Command: $0 $@"\n'

    # Cannot set env vars before calling "log" commands, because they would
    # affect the "log" executable.
    for key, value in env.items():
        ret += f'log -t cr_wrap.sh -- "{key}={value}"\n'

    for key, value in env.items():
        ret += f'export {key}="{value}"\n'

    ret += """
exec "$@"
"""
    return ret


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument('--output', required=True)
    parser.add_argument('--arch', required=True)
    parser.add_argument('--hwasan', action='store_true', default=False)
    parser.add_argument('--asan', action='store_true', default=False)
    parser.add_argument('--env')
    args = parser.parse_args()

    env = {}
    if args.env:
        for prop in args.env.split():
            key, value = prop.split('=', 1)
            env[key] = value
    output_path = pathlib.Path(args.output)
    output_path.write_text(_generate(args.arch, args.hwasan, args.asan, env))
    output_path.chmod(0o755)


if __name__ == '__main__':
    main()