print_to_stream.inl

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// # This file is a part of toml++ and is subject to the the terms of the MIT license.
// # Copyright (c) Mark Gillard <mark.gillard@outlook.com.au>
// # See https://github.com/marzer/tomlplusplus/blob/master/LICENSE for the full license text.
//  SPDX-License-Identifier: MIT
#pragma once
 
// # {{
#include "preprocessor.hpp"
#if !TOML_IMPLEMENTATION
#error This is an implementation-only header.
#endif
// # }}
 
#include "array.hpp"
#include "date_time.hpp"
#include "print_to_stream.hpp"
#include "source_region.hpp"
#include "table.hpp"
#include "toml_formatter.hpp"
#include "value.hpp"
TOML_DISABLE_WARNINGS;
#include <ostream>
#if TOML_INT_CHARCONV || TOML_FLOAT_CHARCONV
#include <charconv>
#endif
#if !TOML_INT_CHARCONV || !TOML_FLOAT_CHARCONV
#include <sstream>
#endif
#if !TOML_INT_CHARCONV
#include <iomanip>
#endif
TOML_ENABLE_WARNINGS;
#include "header_start.hpp"
 
TOML_ANON_NAMESPACE_START {
  template <typename T>
  inline constexpr size_t charconv_buffer_length = 0;
 
  template <>
  inline constexpr size_t charconv_buffer_length<int8_t> = 4;  // strlen("-128")
 
  template <>
  inline constexpr size_t charconv_buffer_length<int16_t> = 6;  // strlen("-32768")
 
  template <>
  inline constexpr size_t charconv_buffer_length<int32_t> = 11;  // strlen("-2147483648")
 
  template <>
  inline constexpr size_t charconv_buffer_length<int64_t> = 20;  // strlen("-9223372036854775808")
 
  template <>
  inline constexpr size_t charconv_buffer_length<uint8_t> = 3;  // strlen("255")
 
  template <>
  inline constexpr size_t charconv_buffer_length<uint16_t> = 5;  // strlen("65535")
 
  template <>
  inline constexpr size_t charconv_buffer_length<uint32_t> = 10;  // strlen("4294967295")
 
  template <>
  inline constexpr size_t charconv_buffer_length<uint64_t> = 20;  // strlen("18446744073709551615")
 
  template <>
  inline constexpr size_t charconv_buffer_length<float> = 64;
 
  template <>
  inline constexpr size_t charconv_buffer_length<double> = 64;
 
  template <typename T>
  TOML_INTERNAL_LINKAGE void print_integer_to_stream(
      std::ostream & stream, T val, value_flags format = {}, size_t min_digits = 0) {
    if (!val) {
      if (!min_digits) min_digits = 1;
 
      for (size_t i = 0; i < min_digits; i++) stream.put('0');
 
      return;
    }
 
    static constexpr auto value_flags_mask = value_flags::format_as_binary |
                                             value_flags::format_as_octal |
                                             value_flags::format_as_hexadecimal;
    format &= value_flags_mask;
 
    int base = 10;
    if (format != value_flags::none && val > T{}) {
      switch (format) {
        case value_flags::format_as_binary:
          base = 2;
          break;
        case value_flags::format_as_octal:
          base = 8;
          break;
        case value_flags::format_as_hexadecimal:
          base = 16;
          break;
        default:
          break;
      }
    }
 
#if TOML_INT_CHARCONV
 
    char       buf[(sizeof(T) * CHAR_BIT)];
    const auto res = std::to_chars(buf, buf + sizeof(buf), val, base);
    const auto len = static_cast<size_t>(res.ptr - buf);
    for (size_t i = len; i < min_digits; i++) stream.put('0');
    if (base == 16) {
      for (size_t i = 0; i < len; i++)
        if (buf[i] >= 'a') buf[i] -= 32;
    }
    impl::print_to_stream(stream, buf, len);
 
#else
 
    using unsigned_type =
        std::conditional_t<(sizeof(T) > sizeof(unsigned)), std::make_unsigned_t<T>, unsigned>;
    using cast_type =
        std::conditional_t<std::is_signed_v<T>, std::make_signed_t<unsigned_type>, unsigned_type>;
 
    if (base == 2) {
      const auto len = sizeof(T) * CHAR_BIT;
      for (size_t i = len; i < min_digits; i++) stream.put('0');
 
      bool          found_one = false;
      const auto    v         = static_cast<unsigned_type>(val);
      unsigned_type mask      = unsigned_type{1} << (len - 1u);
      for (size_t i = 0; i < len; i++) {
        if ((v & mask)) {
          stream.put('1');
          found_one = true;
        } else if (found_one)
          stream.put('0');
        mask >>= 1;
      }
    } else {
      std::ostringstream ss;
      ss.imbue(std::locale::classic());
      ss << std::uppercase << std::setbase(base);
      if (min_digits) ss << std::setfill('0') << std::setw(static_cast<int>(min_digits));
      ss << static_cast<cast_type>(val);
      const auto str = std::move(ss).str();
      impl::print_to_stream(stream, str);
    }
 
#endif
  }
 
  template <typename T>
  TOML_INTERNAL_LINKAGE void print_floating_point_to_stream(
      std::ostream & stream, T val, value_flags format, [[maybe_unused]] bool relaxed_precision) {
    switch (impl::fpclassify(val)) {
      case impl::fp_class::neg_inf:
        impl::print_to_stream(stream, "-inf"sv);
        break;
 
      case impl::fp_class::pos_inf:
        impl::print_to_stream(stream, "inf"sv);
        break;
 
      case impl::fp_class::nan:
        impl::print_to_stream(stream, "nan"sv);
        break;
 
      case impl::fp_class::ok: {
        static constexpr auto needs_decimal_point = [](auto&& s) noexcept {
          for (auto c : s)
            if (c == '.' || c == 'E' || c == 'e') return false;
          return true;
        };
 
#if TOML_FLOAT_CHARCONV
 
        const auto hex = !!(format & value_flags::format_as_hexadecimal);
        char       buf[charconv_buffer_length<T>];
        auto       res = hex ? std::to_chars(buf, buf + sizeof(buf), val, std::chars_format::hex)
                             : std::to_chars(buf, buf + sizeof(buf), val);
        auto       str = std::string_view{buf, static_cast<size_t>(res.ptr - buf)};
 
        char buf2[charconv_buffer_length<T>];
        if (!hex && relaxed_precision) {
          res = std::to_chars(buf2, buf2 + sizeof(buf2), val, std::chars_format::general, 6);
          const auto str2 = std::string_view{buf2, static_cast<size_t>(res.ptr - buf2)};
          if (str2.length() < str.length()) str = str2;
        }
 
        impl::print_to_stream(stream, str);
        if (!hex && needs_decimal_point(str)) toml::impl::print_to_stream(stream, ".0"sv);
 
#else
 
        std::ostringstream ss;
        ss.imbue(std::locale::classic());
        if (!relaxed_precision) ss.precision(std::numeric_limits<T>::max_digits10);
        if (!!(format & value_flags::format_as_hexadecimal)) ss << std::hexfloat;
        ss << val;
        const auto str = std::move(ss).str();
        impl::print_to_stream(stream, str);
        if (!(format & value_flags::format_as_hexadecimal) && needs_decimal_point(str))
          impl::print_to_stream(stream, ".0"sv);
 
#endif
      } break;
 
      default:
        TOML_UNREACHABLE;
    }
  }
}
TOML_ANON_NAMESPACE_END;
 
TOML_IMPL_NAMESPACE_START {
  TOML_EXTERNAL_LINKAGE
  TOML_ATTR(nonnull)
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const char* val, size_t len) {
    stream.write(val, static_cast<std::streamsize>(len));
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, std::string_view val) {
    stream.write(val.data(), static_cast<std::streamsize>(val.length()));
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const std::string& val) {
    stream.write(val.data(), static_cast<std::streamsize>(val.length()));
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, char val) {
    stream.put(val);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, signed char val, value_flags format,
                                     size_t min_digits) {
    TOML_ANON_NAMESPACE::print_integer_to_stream(stream, val, format, min_digits);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, signed short val, value_flags format,
                                     size_t min_digits) {
    TOML_ANON_NAMESPACE::print_integer_to_stream(stream, val, format, min_digits);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, signed int val, value_flags format,
                                     size_t min_digits) {
    TOML_ANON_NAMESPACE::print_integer_to_stream(stream, val, format, min_digits);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, signed long val, value_flags format,
                                     size_t min_digits) {
    TOML_ANON_NAMESPACE::print_integer_to_stream(stream, val, format, min_digits);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, signed long long val,
                                     value_flags format, size_t min_digits) {
    TOML_ANON_NAMESPACE::print_integer_to_stream(stream, val, format, min_digits);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, unsigned char val, value_flags format,
                                     size_t min_digits) {
    TOML_ANON_NAMESPACE::print_integer_to_stream(stream, val, format, min_digits);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, unsigned short val, value_flags format,
                                     size_t min_digits) {
    TOML_ANON_NAMESPACE::print_integer_to_stream(stream, val, format, min_digits);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, unsigned int val, value_flags format,
                                     size_t min_digits) {
    TOML_ANON_NAMESPACE::print_integer_to_stream(stream, val, format, min_digits);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, unsigned long val, value_flags format,
                                     size_t min_digits) {
    TOML_ANON_NAMESPACE::print_integer_to_stream(stream, val, format, min_digits);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, unsigned long long val,
                                     value_flags format, size_t min_digits) {
    TOML_ANON_NAMESPACE::print_integer_to_stream(stream, val, format, min_digits);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, float val, value_flags format,
                                     bool relaxed_precision) {
    TOML_ANON_NAMESPACE::print_floating_point_to_stream(stream, val, format, relaxed_precision);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, double val, value_flags format,
                                     bool relaxed_precision) {
    TOML_ANON_NAMESPACE::print_floating_point_to_stream(stream, val, format, relaxed_precision);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, bool val) {
    print_to_stream(stream, val ? "true"sv : "false"sv);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const toml::date& val) {
    print_to_stream(stream, val.year, {}, 4);
    stream.put('-');
    print_to_stream(stream, val.month, {}, 2);
    stream.put('-');
    print_to_stream(stream, val.day, {}, 2);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const toml::time& val) {
    print_to_stream(stream, val.hour, {}, 2);
    stream.put(':');
    print_to_stream(stream, val.minute, {}, 2);
    stream.put(':');
    print_to_stream(stream, val.second, {}, 2);
    if (val.nanosecond && val.nanosecond <= 999999999u) {
      stream.put('.');
      auto   ns     = val.nanosecond;
      size_t digits = 9u;
      while (ns % 10u == 0u) {
        ns /= 10u;
        digits--;
      }
      print_to_stream(stream, ns, {}, digits);
    }
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const toml::time_offset& val) {
    if (!val.minutes) {
      stream.put('Z');
      return;
    }
 
    auto mins = static_cast<int>(val.minutes);
    if (mins < 0) {
      stream.put('-');
      mins = -mins;
    } else
      stream.put('+');
    const auto hours = mins / 60;
    if (hours) {
      print_to_stream(stream, static_cast<unsigned int>(hours), {}, 2);
      mins -= hours * 60;
    } else
      print_to_stream(stream, "00"sv);
    stream.put(':');
    print_to_stream(stream, static_cast<unsigned int>(mins), {}, 2);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const toml::date_time& val) {
    print_to_stream(stream, val.date);
    stream.put('T');
    print_to_stream(stream, val.time);
    if (val.offset) print_to_stream(stream, *val.offset);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const source_position& val) {
    print_to_stream(stream, "line "sv);
    print_to_stream(stream, val.line);
    print_to_stream(stream, ", column "sv);
    print_to_stream(stream, val.column);
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const source_region& val) {
    print_to_stream(stream, val.begin);
    if (val.path) {
      print_to_stream(stream, " of '"sv);
      print_to_stream(stream, *val.path);
      stream.put('\'');
    }
  }
 
#if TOML_ENABLE_FORMATTERS
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const array& arr) {
    stream << toml_formatter{arr};
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const table& tbl) {
    stream << toml_formatter{tbl};
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const value<std::string>& val) {
    stream << toml_formatter{val};
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const value<int64_t>& val) {
    stream << toml_formatter{val};
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const value<double>& val) {
    stream << toml_formatter{val};
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const value<bool>& val) {
    stream << toml_formatter{val};
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const value<date>& val) {
    stream << toml_formatter{val};
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const value<time>& val) {
    stream << toml_formatter{val};
  }
 
  TOML_EXTERNAL_LINKAGE
  void TOML_CALLCONV print_to_stream(std::ostream & stream, const value<date_time>& val) {
    stream << toml_formatter{val};
  }
 
#endif
}
TOML_IMPL_NAMESPACE_END;
 
#include "header_end.hpp"