libcxx/include/__format/formatter_pointer.h

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP___FORMAT_FORMATTER_POINTER_H
#define _LIBCPP___FORMAT_FORMATTER_POINTER_H

#include <__config>
#include <__cstddef/nullptr_t.h>
#include <__format/concepts.h>
#include <__format/format_parse_context.h>
#include <__format/formatter.h>
#include <__format/formatter_integral.h>
#include <__format/formatter_output.h>
#include <__format/parser_std_format_spec.h>
#include <cstdint>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#  pragma GCC system_header
#endif

_LIBCPP_BEGIN_NAMESPACE_STD

#if _LIBCPP_STD_VER >= 20

template <__fmt_char_type _CharT>
struct __formatter_pointer {
public:
  template <class _ParseContext>
  _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
    typename _ParseContext::iterator __result = __parser_.__parse(__ctx, __format_spec::__fields_pointer);
    __format_spec::__process_display_type_pointer(__parser_.__type_, "a pointer");
    return __result;
  }

  template <class _FormatContext>
  _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(const void* __ptr, _FormatContext& __ctx) const {
    __format_spec::__parsed_specifications<_CharT> __specs = __parser_.__get_parsed_std_specifications(__ctx);
    __specs.__std_.__alternate_form_                       = true;
    __specs.__std_.__type_ =
        __specs.__std_.__type_ == __format_spec::__type::__pointer_upper_case
            ? __format_spec::__type::__hexadecimal_upper_case
            : __format_spec::__type::__hexadecimal_lower_case;

    return __formatter::__format_integer(reinterpret_cast<uintptr_t>(__ptr), __ctx, __specs);
  }

  __format_spec::__parser<_CharT> __parser_;
};

// [format.formatter.spec]/2.4
// For each charT, the pointer type specializations template<>
// - struct formatter<nullptr_t, charT>;
// - template<> struct formatter<void*, charT>;
// - template<> struct formatter<const void*, charT>;
template <__fmt_char_type _CharT>
struct formatter<nullptr_t, _CharT> : public __formatter_pointer<_CharT> {};
template <__fmt_char_type _CharT>
struct formatter<void*, _CharT> : public __formatter_pointer<_CharT> {};
template <__fmt_char_type _CharT>
struct formatter<const void*, _CharT> : public __formatter_pointer<_CharT> {};

#  if _LIBCPP_STD_VER >= 23
template <>
inline constexpr bool enable_nonlocking_formatter_optimization<nullptr_t> = true;
template <>
inline constexpr bool enable_nonlocking_formatter_optimization<void*> = true;
template <>
inline constexpr bool enable_nonlocking_formatter_optimization<const void*> = true;
#  endif // _LIBCPP_STD_VER >= 23
#endif   // _LIBCPP_STD_VER >= 20

_LIBCPP_END_NAMESPACE_STD

#endif // _LIBCPP___FORMAT_FORMATTER_POINTER_H