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1// -*- C++ -*-2//===----------------------------------------------------------------------===//3//4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.5// See https://llvm.org/LICENSE.txt for license information.6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception7//8//===----------------------------------------------------------------------===//9 10#ifndef _LIBCPP___FORMAT_FORMATTER_STRING_H11#define _LIBCPP___FORMAT_FORMATTER_STRING_H12 13#include <__assert>14#include <__config>15#include <__format/concepts.h>16#include <__format/format_parse_context.h>17#include <__format/formatter.h>18#include <__format/formatter_output.h>19#include <__format/parser_std_format_spec.h>20#include <__format/write_escaped.h>21#include <cstddef>22#include <string>23#include <string_view>24 25#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)26# pragma GCC system_header27#endif28 29_LIBCPP_BEGIN_NAMESPACE_STD30 31#if _LIBCPP_STD_VER >= 2032 33template <__fmt_char_type _CharT>34struct __formatter_string {35public:36 template <class _ParseContext>37 _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {38 typename _ParseContext::iterator __result = __parser_.__parse(__ctx, __format_spec::__fields_string);39 __format_spec::__process_display_type_string(__parser_.__type_);40 return __result;41 }42 43 template <class _FormatContext>44 _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator45 format(basic_string_view<_CharT> __str, _FormatContext& __ctx) const {46# if _LIBCPP_STD_VER >= 2347 if (__parser_.__type_ == __format_spec::__type::__debug)48 return __formatter::__format_escaped_string(__str, __ctx.out(), __parser_.__get_parsed_std_specifications(__ctx));49# endif50 51 return __formatter::__write_string(__str, __ctx.out(), __parser_.__get_parsed_std_specifications(__ctx));52 }53 54# if _LIBCPP_STD_VER >= 2355 _LIBCPP_HIDE_FROM_ABI constexpr void set_debug_format() { __parser_.__type_ = __format_spec::__type::__debug; }56# endif57 58 __format_spec::__parser<_CharT> __parser_{.__alignment_ = __format_spec::__alignment::__left};59};60 61// Formatter const char*.62template <__fmt_char_type _CharT>63struct formatter<const _CharT*, _CharT> : public __formatter_string<_CharT> {64 using _Base _LIBCPP_NODEBUG = __formatter_string<_CharT>;65 66 template <class _FormatContext>67 _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(const _CharT* __str, _FormatContext& __ctx) const {68 _LIBCPP_ASSERT_INTERNAL(__str, "The basic_format_arg constructor should have prevented an invalid pointer.");69 // Converting the input to a basic_string_view means the data is looped over twice;70 // - once to determine the length, and71 // - once to process the data.72 //73 // This sounds slower than writing the output directly. However internally74 // the output algorithms have optimizations for "bulk" operations, which75 // makes this faster than a single-pass character-by-character output.76 return _Base::format(basic_string_view<_CharT>(__str), __ctx);77 }78};79 80// Formatter char*.81template <__fmt_char_type _CharT>82struct formatter<_CharT*, _CharT> : public formatter<const _CharT*, _CharT> {83 using _Base _LIBCPP_NODEBUG = formatter<const _CharT*, _CharT>;84 85 template <class _FormatContext>86 _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(_CharT* __str, _FormatContext& __ctx) const {87 return _Base::format(__str, __ctx);88 }89};90 91// Formatter char[].92template <__fmt_char_type _CharT, size_t _Size>93struct formatter<_CharT[_Size], _CharT> : public __formatter_string<_CharT> {94 using _Base _LIBCPP_NODEBUG = __formatter_string<_CharT>;95 96 template <class _FormatContext>97 _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator98 format(const _CharT (&__str)[_Size], _FormatContext& __ctx) const {99 const _CharT* const __pzero = char_traits<_CharT>::find(__str, _Size, _CharT{});100 _LIBCPP_ASSERT_VALID_INPUT_RANGE(__pzero != nullptr, "formatting a non-null-terminated array");101 return _Base::format(basic_string_view<_CharT>(__str, static_cast<size_t>(__pzero - __str)), __ctx);102 }103};104 105// Formatter std::string.106template <__fmt_char_type _CharT, class _Traits, class _Allocator>107struct formatter<basic_string<_CharT, _Traits, _Allocator>, _CharT> : public __formatter_string<_CharT> {108 using _Base _LIBCPP_NODEBUG = __formatter_string<_CharT>;109 110 template <class _FormatContext>111 _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator112 format(const basic_string<_CharT, _Traits, _Allocator>& __str, _FormatContext& __ctx) const {113 // Drop _Traits and _Allocator to have one std::basic_string formatter.114 return _Base::format(basic_string_view<_CharT>(__str.data(), __str.size()), __ctx);115 }116};117 118// Formatter std::string_view.119template <__fmt_char_type _CharT, class _Traits>120struct formatter<basic_string_view<_CharT, _Traits>, _CharT> : public __formatter_string<_CharT> {121 using _Base _LIBCPP_NODEBUG = __formatter_string<_CharT>;122 123 template <class _FormatContext>124 _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator125 format(basic_string_view<_CharT, _Traits> __str, _FormatContext& __ctx) const {126 // Drop _Traits to have one std::basic_string_view formatter.127 return _Base::format(basic_string_view<_CharT>(__str.data(), __str.size()), __ctx);128 }129};130 131# if _LIBCPP_HAS_WIDE_CHARACTERS132template <>133struct formatter<char*, wchar_t> : __disabled_formatter {};134template <>135struct formatter<const char*, wchar_t> : __disabled_formatter {};136template <size_t _Size>137struct formatter<char[_Size], wchar_t> : __disabled_formatter {};138template <class _Traits, class _Allocator>139struct formatter<basic_string<char, _Traits, _Allocator>, wchar_t> : __disabled_formatter {};140template <class _Traits>141struct formatter<basic_string_view<char, _Traits>, wchar_t> : __disabled_formatter {};142# endif // _LIBCPP_HAS_WIDE_CHARACTERS143 144# if _LIBCPP_STD_VER >= 23145template <>146inline constexpr bool enable_nonlocking_formatter_optimization<char*> = true;147template <>148inline constexpr bool enable_nonlocking_formatter_optimization<const char*> = true;149template <size_t _Size>150inline constexpr bool enable_nonlocking_formatter_optimization<char[_Size]> = true;151template <class _Traits, class _Allocator>152inline constexpr bool enable_nonlocking_formatter_optimization<basic_string<char, _Traits, _Allocator>> = true;153template <class _Traits>154inline constexpr bool enable_nonlocking_formatter_optimization<basic_string_view<char, _Traits>> = true;155 156# if _LIBCPP_HAS_WIDE_CHARACTERS157template <>158inline constexpr bool enable_nonlocking_formatter_optimization<wchar_t*> = true;159template <>160inline constexpr bool enable_nonlocking_formatter_optimization<const wchar_t*> = true;161template <size_t _Size>162inline constexpr bool enable_nonlocking_formatter_optimization<wchar_t[_Size]> = true;163template <class _Traits, class _Allocator>164inline constexpr bool enable_nonlocking_formatter_optimization<basic_string<wchar_t, _Traits, _Allocator>> = true;165template <class _Traits>166inline constexpr bool enable_nonlocking_formatter_optimization<basic_string_view<wchar_t, _Traits>> = true;167# endif // _LIBCPP_HAS_WIDE_CHARACTERS168# endif // _LIBCPP_STD_VER >= 23169#endif // _LIBCPP_STD_VER >= 20170 171_LIBCPP_END_NAMESPACE_STD172 173#endif // _LIBCPP___FORMAT_FORMATTER_STRING_H174