geode/codegen/Broma/PEGTL-3.2.7/include/tao/pegtl/contrib/limit_depth.hpp
2022-07-30 19:24:03 +03:00

83 lines
2.2 KiB
C++
Executable file

// Copyright (c) 2021-2022 Dr. Colin Hirsch and Daniel Frey
// Please see LICENSE for license or visit https://github.com/taocpp/PEGTL/
#ifndef TAO_PEGTL_CONTRIB_LIMIT_DEPTH_HPP
#define TAO_PEGTL_CONTRIB_LIMIT_DEPTH_HPP
#include "../apply_mode.hpp"
#include "../config.hpp"
#include "../match.hpp"
#include "../nothing.hpp"
#include "../rewind_mode.hpp"
#if defined( __cpp_exceptions )
#include "../parse_error.hpp"
#else
#include <cstdio>
#include <exception>
#endif
namespace TAO_PEGTL_NAMESPACE
{
namespace internal
{
struct [[nodiscard]] depth_guard
{
std::size_t& m_depth;
explicit depth_guard( std::size_t& depth ) noexcept
: m_depth( depth )
{
++m_depth;
}
depth_guard( depth_guard&& ) = delete;
depth_guard( const depth_guard& ) = delete;
~depth_guard()
{
--m_depth;
}
depth_guard& operator=( depth_guard&& ) = delete;
depth_guard& operator=( const depth_guard& ) = delete;
};
} // namespace internal
template< std::size_t Maximum >
struct limit_depth
: maybe_nothing
{
template< typename Rule,
apply_mode A,
rewind_mode M,
template< typename... >
class Action,
template< typename... >
class Control,
typename ParseInput,
typename... States >
[[nodiscard]] static bool match( ParseInput& in, States&&... st )
{
if constexpr( Control< Rule >::enable ) {
const internal::depth_guard dg( in.private_depth );
if( in.private_depth > Maximum ) {
#if defined( __cpp_exceptions )
throw TAO_PEGTL_NAMESPACE::parse_error( "maximum parser rule nesting depth exceeded", in );
#else
std::fputs( "maximum parser rule nesting depth exceeded\n", stderr );
std::terminate();
#endif
}
return TAO_PEGTL_NAMESPACE::match< Rule, A, M, Action, Control >( in, st... );
}
else {
return TAO_PEGTL_NAMESPACE::match< Rule, A, M, Action, Control >( in, st... );
}
}
};
} // namespace TAO_PEGTL_NAMESPACE
#endif