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 // Formatting library for C++ - legacy printf implementation
 //
 // Copyright (c) 2012 - 2016, Victor Zverovich
 // All rights reserved.
 //
 // For the license information refer to format.h.
 
 #ifndef FMT_PRINTF_H_
 #define FMT_PRINTF_H_
 
 #include <algorithm>  // std::max
 #include <limits>     // std::numeric_limits
 
 #include "format.h"
 
 FMT_BEGIN_NAMESPACE
 FMT_BEGIN_EXPORT
 
 template <typename T> struct printf_formatter {
   printf_formatter() = delete;
 };
 
 template <typename Char> class basic_printf_context {
  private:
   detail::buffer_appender<Char> out_;
   basic_format_args<basic_printf_context> args_;
 
   static_assert(std::is_same<Char, char>::value ||
                     std::is_same<Char, wchar_t>::value,
                 "Unsupported code unit type.");
 
  public:
   using char_type = Char;
   using parse_context_type = basic_format_parse_context<Char>;
   template <typename T> using formatter_type = printf_formatter<T>;
 
   /**
     \rst
     Constructs a ``printf_context`` object. References to the arguments are
     stored in the context object so make sure they have appropriate lifetimes.
     \endrst
    */
   basic_printf_context(detail::buffer_appender<Char> out,
                        basic_format_args<basic_printf_context> args)
       : out_(out), args_(args) {}
 
   auto out() -> detail::buffer_appender<Char> { return out_; }
   void advance_to(detail::buffer_appender<Char>) {}
 
   auto locale() -> detail::locale_ref { return {}; }
 
   auto arg(int id) const -> basic_format_arg<basic_printf_context> {
     return args_.get(id);
   }
 
   FMT_CONSTEXPR void on_error(const char* message) {
     detail::error_handler().on_error(message);
   }
 };
 
 namespace detail {
 
 // Checks if a value fits in int - used to avoid warnings about comparing
 // signed and unsigned integers.
 template <bool IsSigned> struct int_checker {
   template <typename T> static auto fits_in_int(T value) -> bool {
     unsigned max = max_value<int>();
     return value <= max;
   }
   static auto fits_in_int(bool) -> bool { return true; }
 };
 
 template <> struct int_checker<true> {
   template <typename T> static auto fits_in_int(T value) -> bool {
     return value >= (std::numeric_limits<int>::min)() &&
            value <= max_value<int>();
   }
   static auto fits_in_int(int) -> bool { return true; }
 };
 
 struct printf_precision_handler {
   template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
   auto operator()(T value) -> int {
     if (!int_checker<std::numeric_limits<T>::is_signed>::fits_in_int(value))
       throw_format_error("number is too big");
     return (std::max)(static_cast<int>(value), 0);
   }
 
   template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
   auto operator()(T) -> int {
     throw_format_error("precision is not integer");
     return 0;
   }
 };
 
 // An argument visitor that returns true iff arg is a zero integer.
 struct is_zero_int {
   template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
   auto operator()(T value) -> bool {
     return value == 0;
   }
 
   template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
   auto operator()(T) -> bool {
     return false;
   }
 };
 
 template <typename T> struct make_unsigned_or_bool : std::make_unsigned<T> {};
 
 template <> struct make_unsigned_or_bool<bool> {
   using type = bool;
 };
 
 template <typename T, typename Context> class arg_converter {
  private:
   using char_type = typename Context::char_type;
 
   basic_format_arg<Context>& arg_;
   char_type type_;
 
  public:
   arg_converter(basic_format_arg<Context>& arg, char_type type)
       : arg_(arg), type_(type) {}
 
   void operator()(bool value) {
     if (type_ != 's') operator()<bool>(value);
   }
 
   template <typename U, FMT_ENABLE_IF(std::is_integral<U>::value)>
   void operator()(U value) {
     bool is_signed = type_ == 'd' || type_ == 'i';
     using target_type = conditional_t<std::is_same<T, void>::value, U, T>;
     if (const_check(sizeof(target_type) <= sizeof(int))) {
       // Extra casts are used to silence warnings.
       if (is_signed) {
         auto n = static_cast<int>(static_cast<target_type>(value));
         arg_ = detail::make_arg<Context>(n);
       } else {
         using unsigned_type = typename make_unsigned_or_bool<target_type>::type;
         auto n = static_cast<unsigned>(static_cast<unsigned_type>(value));
         arg_ = detail::make_arg<Context>(n);
       }
     } else {
       if (is_signed) {
         // glibc's printf doesn't sign extend arguments of smaller types:
         //   std::printf("%lld", -42);  // prints "4294967254"
         // but we don't have to do the same because it's a UB.
         auto n = static_cast<long long>(value);
         arg_ = detail::make_arg<Context>(n);
       } else {
         auto n = static_cast<typename make_unsigned_or_bool<U>::type>(value);
         arg_ = detail::make_arg<Context>(n);
       }
     }
   }
 
   template <typename U, FMT_ENABLE_IF(!std::is_integral<U>::value)>
   void operator()(U) {}  // No conversion needed for non-integral types.
 };
 
 // Converts an integer argument to T for printf, if T is an integral type.
 // If T is void, the argument is converted to corresponding signed or unsigned
 // type depending on the type specifier: 'd' and 'i' - signed, other -
 // unsigned).
 template <typename T, typename Context, typename Char>
 void convert_arg(basic_format_arg<Context>& arg, Char type) {
   visit_format_arg(arg_converter<T, Context>(arg, type), arg);
 }
 
 // Converts an integer argument to char for printf.
 template <typename Context> class char_converter {
  private:
   basic_format_arg<Context>& arg_;
 
  public:
   explicit char_converter(basic_format_arg<Context>& arg) : arg_(arg) {}
 
   template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
   void operator()(T value) {
     auto c = static_cast<typename Context::char_type>(value);
     arg_ = detail::make_arg<Context>(c);
   }
 
   template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
   void operator()(T) {}  // No conversion needed for non-integral types.
 };
 
 // An argument visitor that return a pointer to a C string if argument is a
 // string or null otherwise.
 template <typename Char> struct get_cstring {
   template <typename T> auto operator()(T) -> const Char* { return nullptr; }
   auto operator()(const Char* s) -> const Char* { return s; }
 };
 
 // Checks if an argument is a valid printf width specifier and sets
 // left alignment if it is negative.
 template <typename Char> class printf_width_handler {
  private:
   format_specs<Char>& specs_;
 
  public:
   explicit printf_width_handler(format_specs<Char>& specs) : specs_(specs) {}
 
   template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
   auto operator()(T value) -> unsigned {
     auto width = static_cast<uint32_or_64_or_128_t<T>>(value);
     if (detail::is_negative(value)) {
       specs_.align = align::left;
       width = 0 - width;
     }
     unsigned int_max = max_value<int>();
     if (width > int_max) throw_format_error("number is too big");
     return static_cast<unsigned>(width);
   }
 
   template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
   auto operator()(T) -> unsigned {
     throw_format_error("width is not integer");
     return 0;
   }
 };
 
 // Workaround for a bug with the XL compiler when initializing
 // printf_arg_formatter's base class.
 template <typename Char>
 auto make_arg_formatter(buffer_appender<Char> iter, format_specs<Char>& s)
     -> arg_formatter<Char> {
   return {iter, s, locale_ref()};
 }
 
 // The ``printf`` argument formatter.
 template <typename Char>
 class printf_arg_formatter : public arg_formatter<Char> {
  private:
   using base = arg_formatter<Char>;
   using context_type = basic_printf_context<Char>;
 
   context_type& context_;
 
   void write_null_pointer(bool is_string = false) {
     auto s = this->specs;
     s.type = presentation_type::none;
     write_bytes(this->out, is_string ? "(null)" : "(nil)", s);
   }
 
  public:
   printf_arg_formatter(buffer_appender<Char> iter, format_specs<Char>& s,
                        context_type& ctx)
       : base(make_arg_formatter(iter, s)), context_(ctx) {}
 
   void operator()(monostate value) { base::operator()(value); }
 
   template <typename T, FMT_ENABLE_IF(detail::is_integral<T>::value)>
   void operator()(T value) {
     // MSVC2013 fails to compile separate overloads for bool and Char so use
     // std::is_same instead.
     if (!std::is_same<T, Char>::value) {
       base::operator()(value);
       return;
     }
     format_specs<Char> fmt_specs = this->specs;
     if (fmt_specs.type != presentation_type::none &&
         fmt_specs.type != presentation_type::chr) {
       return (*this)(static_cast<int>(value));
     }
     fmt_specs.sign = sign::none;
     fmt_specs.alt = false;
     fmt_specs.fill[0] = ' ';  // Ignore '0' flag for char types.
     // align::numeric needs to be overwritten here since the '0' flag is
     // ignored for non-numeric types
     if (fmt_specs.align == align::none || fmt_specs.align == align::numeric)
       fmt_specs.align = align::right;
     write<Char>(this->out, static_cast<Char>(value), fmt_specs);
   }
 
   template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
   void operator()(T value) {
     base::operator()(value);
   }
 
   /** Formats a null-terminated C string. */
   void operator()(const char* value) {
     if (value)
       base::operator()(value);
     else
       write_null_pointer(this->specs.type != presentation_type::pointer);
   }
 
   /** Formats a null-terminated wide C string. */
   void operator()(const wchar_t* value) {
     if (value)
       base::operator()(value);
     else
       write_null_pointer(this->specs.type != presentation_type::pointer);
   }
 
   void operator()(basic_string_view<Char> value) { base::operator()(value); }
 
   /** Formats a pointer. */
   void operator()(const void* value) {
     if (value)
       base::operator()(value);
     else
       write_null_pointer();
   }
 
   /** Formats an argument of a custom (user-defined) type. */
   void operator()(typename basic_format_arg<context_type>::handle handle) {
     auto parse_ctx = basic_format_parse_context<Char>({});
     handle.format(parse_ctx, context_);
   }
 };
 
 template <typename Char>
 void parse_flags(format_specs<Char>& specs, const Char*& it, const Char* end) {
   for (; it != end; ++it) {
     switch (*it) {
     case '-':
       specs.align = align::left;
       break;
     case '+':
       specs.sign = sign::plus;
       break;
     case '0':
       specs.fill[0] = '0';
       break;
     case ' ':
       if (specs.sign != sign::plus) specs.sign = sign::space;
       break;
     case '#':
       specs.alt = true;
       break;
     default:
       return;
     }
   }
 }
 
 template <typename Char, typename GetArg>
 auto parse_header(const Char*& it, const Char* end, format_specs<Char>& specs,
                   GetArg get_arg) -> int {
   int arg_index = -1;
   Char c = *it;
   if (c >= '0' && c <= '9') {
     // Parse an argument index (if followed by '$') or a width possibly
     // preceded with '0' flag(s).
     int value = parse_nonnegative_int(it, end, -1);
     if (it != end && *it == '$') {  // value is an argument index
       ++it;
       arg_index = value != -1 ? value : max_value<int>();
     } else {
       if (c == '0') specs.fill[0] = '0';
       if (value != 0) {
         // Nonzero value means that we parsed width and don't need to
         // parse it or flags again, so return now.
         if (value == -1) throw_format_error("number is too big");
         specs.width = value;
         return arg_index;
       }
     }
   }
   parse_flags(specs, it, end);
   // Parse width.
   if (it != end) {
     if (*it >= '0' && *it <= '9') {
       specs.width = parse_nonnegative_int(it, end, -1);
       if (specs.width == -1) throw_format_error("number is too big");
     } else if (*it == '*') {
       ++it;
       specs.width = static_cast<int>(visit_format_arg(
           detail::printf_width_handler<Char>(specs), get_arg(-1)));
     }
   }
   return arg_index;
 }
 
 inline auto parse_printf_presentation_type(char c, type t)
     -> presentation_type {
   using pt = presentation_type;
   constexpr auto integral_set = sint_set | uint_set | bool_set | char_set;
   switch (c) {
   case 'd':
     return in(t, integral_set) ? pt::dec : pt::none;
   case 'o':
     return in(t, integral_set) ? pt::oct : pt::none;
   case 'x':
     return in(t, integral_set) ? pt::hex_lower : pt::none;
   case 'X':
     return in(t, integral_set) ? pt::hex_upper : pt::none;
   case 'a':
     return in(t, float_set) ? pt::hexfloat_lower : pt::none;
   case 'A':
     return in(t, float_set) ? pt::hexfloat_upper : pt::none;
   case 'e':
     return in(t, float_set) ? pt::exp_lower : pt::none;
   case 'E':
     return in(t, float_set) ? pt::exp_upper : pt::none;
   case 'f':
     return in(t, float_set) ? pt::fixed_lower : pt::none;
   case 'F':
     return in(t, float_set) ? pt::fixed_upper : pt::none;
   case 'g':
     return in(t, float_set) ? pt::general_lower : pt::none;
   case 'G':
     return in(t, float_set) ? pt::general_upper : pt::none;
   case 'c':
     return in(t, integral_set) ? pt::chr : pt::none;
   case 's':
     return in(t, string_set | cstring_set) ? pt::string : pt::none;
   case 'p':
     return in(t, pointer_set | cstring_set) ? pt::pointer : pt::none;
   default:
     return pt::none;
   }
 }
 
 template <typename Char, typename Context>
 void vprintf(buffer<Char>& buf, basic_string_view<Char> format,
              basic_format_args<Context> args) {
   using iterator = buffer_appender<Char>;
   auto out = iterator(buf);
   auto context = basic_printf_context<Char>(out, args);
   auto parse_ctx = basic_format_parse_context<Char>(format);
 
   // Returns the argument with specified index or, if arg_index is -1, the next
   // argument.
   auto get_arg = [&](int arg_index) {
     if (arg_index < 0)
       arg_index = parse_ctx.next_arg_id();
     else
       parse_ctx.check_arg_id(--arg_index);
     return detail::get_arg(context, arg_index);
   };
 
   const Char* start = parse_ctx.begin();
   const Char* end = parse_ctx.end();
   auto it = start;
   while (it != end) {
     if (!find<false, Char>(it, end, '%', it)) {
       it = end;  // find leaves it == nullptr if it doesn't find '%'.
       break;
     }
     Char c = *it++;
     if (it != end && *it == c) {
       write(out, basic_string_view<Char>(start, to_unsigned(it - start)));
       start = ++it;
       continue;
     }
     write(out, basic_string_view<Char>(start, to_unsigned(it - 1 - start)));
 
     auto specs = format_specs<Char>();
     specs.align = align::right;
 
     // Parse argument index, flags and width.
     int arg_index = parse_header(it, end, specs, get_arg);
     if (arg_index == 0) throw_format_error("argument not found");
 
     // Parse precision.
     if (it != end && *it == '.') {
       ++it;
       c = it != end ? *it : 0;
       if ('0' <= c && c <= '9') {
         specs.precision = parse_nonnegative_int(it, end, 0);
       } else if (c == '*') {
         ++it;
         specs.precision = static_cast<int>(
             visit_format_arg(printf_precision_handler(), get_arg(-1)));
       } else {
         specs.precision = 0;
       }
     }
 
     auto arg = get_arg(arg_index);
     // For d, i, o, u, x, and X conversion specifiers, if a precision is
     // specified, the '0' flag is ignored
     if (specs.precision >= 0 && arg.is_integral()) {
       // Ignore '0' for non-numeric types or if '-' present.
       specs.fill[0] = ' ';
     }
     if (specs.precision >= 0 && arg.type() == type::cstring_type) {
       auto str = visit_format_arg(get_cstring<Char>(), arg);
       auto str_end = str + specs.precision;
       auto nul = std::find(str, str_end, Char());
       auto sv = basic_string_view<Char>(
           str, to_unsigned(nul != str_end ? nul - str : specs.precision));
       arg = make_arg<basic_printf_context<Char>>(sv);
     }
     if (specs.alt && visit_format_arg(is_zero_int(), arg)) specs.alt = false;
     if (specs.fill[0] == '0') {
       if (arg.is_arithmetic() && specs.align != align::left)
         specs.align = align::numeric;
       else
         specs.fill[0] = ' ';  // Ignore '0' flag for non-numeric types or if '-'
                               // flag is also present.
     }
 
     // Parse length and convert the argument to the required type.
     c = it != end ? *it++ : 0;
     Char t = it != end ? *it : 0;
     switch (c) {
     case 'h':
       if (t == 'h') {
         ++it;
         t = it != end ? *it : 0;
         convert_arg<signed char>(arg, t);
       } else {
         convert_arg<short>(arg, t);
       }
       break;
     case 'l':
       if (t == 'l') {
         ++it;
         t = it != end ? *it : 0;
         convert_arg<long long>(arg, t);
       } else {
         convert_arg<long>(arg, t);
       }
       break;
     case 'j':
       convert_arg<intmax_t>(arg, t);
       break;
     case 'z':
       convert_arg<size_t>(arg, t);
       break;
     case 't':
       convert_arg<std::ptrdiff_t>(arg, t);
       break;
     case 'L':
       // printf produces garbage when 'L' is omitted for long double, no
       // need to do the same.
       break;
     default:
       --it;
       convert_arg<void>(arg, c);
     }
 
     // Parse type.
     if (it == end) throw_format_error("invalid format string");
     char type = static_cast<char>(*it++);
     if (arg.is_integral()) {
       // Normalize type.
       switch (type) {
       case 'i':
       case 'u':
         type = 'd';
         break;
       case 'c':
         visit_format_arg(char_converter<basic_printf_context<Char>>(arg), arg);
         break;
       }
     }
     specs.type = parse_printf_presentation_type(type, arg.type());
     if (specs.type == presentation_type::none)
       throw_format_error("invalid format specifier");
 
     start = it;
 
     // Format argument.
     visit_format_arg(printf_arg_formatter<Char>(out, specs, context), arg);
   }
   write(out, basic_string_view<Char>(start, to_unsigned(it - start)));
 }
 }  // namespace detail
 
 using printf_context = basic_printf_context<char>;
 using wprintf_context = basic_printf_context<wchar_t>;
 
 using printf_args = basic_format_args<printf_context>;
 using wprintf_args = basic_format_args<wprintf_context>;
 
 /**
   \rst
   Constructs an `~fmt::format_arg_store` object that contains references to
   arguments and can be implicitly converted to `~fmt::printf_args`.
   \endrst
  */
 template <typename... T>
 inline auto make_printf_args(const T&... args)
     -> format_arg_store<printf_context, T...> {
   return {args...};
 }
 
 // DEPRECATED!
 template <typename... T>
 inline auto make_wprintf_args(const T&... args)
     -> format_arg_store<wprintf_context, T...> {
   return {args...};
 }
 
 template <typename Char>
 inline auto vsprintf(
     basic_string_view<Char> fmt,
     basic_format_args<basic_printf_context<type_identity_t<Char>>> args)
     -> std::basic_string<Char> {
   auto buf = basic_memory_buffer<Char>();
   detail::vprintf(buf, fmt, args);
   return to_string(buf);
 }
 
 /**
   \rst
   Formats arguments and returns the result as a string.
 
   **Example**::
 
     std::string message = fmt::sprintf("The answer is %d", 42);
   \endrst
 */
 template <typename S, typename... T,
           typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>>
 inline auto sprintf(const S& fmt, const T&... args) -> std::basic_string<Char> {
   return vsprintf(detail::to_string_view(fmt),
                   fmt::make_format_args<basic_printf_context<Char>>(args...));
 }
 
 template <typename Char>
 inline auto vfprintf(
     std::FILE* f, basic_string_view<Char> fmt,
     basic_format_args<basic_printf_context<type_identity_t<Char>>> args)
     -> int {
   auto buf = basic_memory_buffer<Char>();
   detail::vprintf(buf, fmt, args);
   size_t size = buf.size();
   return std::fwrite(buf.data(), sizeof(Char), size, f) < size
              ? -1
              : static_cast<int>(size);
 }
 
 /**
   \rst
   Prints formatted data to the file *f*.
 
   **Example**::
 
     fmt::fprintf(stderr, "Don't %s!", "panic");
   \endrst
  */
 template <typename S, typename... T, typename Char = char_t<S>>
 inline auto fprintf(std::FILE* f, const S& fmt, const T&... args) -> int {
   return vfprintf(f, detail::to_string_view(fmt),
                   fmt::make_format_args<basic_printf_context<Char>>(args...));
 }
 
 template <typename Char>
 FMT_DEPRECATED inline auto vprintf(
     basic_string_view<Char> fmt,
     basic_format_args<basic_printf_context<type_identity_t<Char>>> args)
     -> int {
   return vfprintf(stdout, fmt, args);
 }
 
 /**
   \rst
   Prints formatted data to ``stdout``.
 
   **Example**::
 
     fmt::printf("Elapsed time: %.2f seconds", 1.23);
   \endrst
  */
 template <typename... T>
 inline auto printf(string_view fmt, const T&... args) -> int {
   return vfprintf(stdout, fmt, make_printf_args(args...));
 }
 template <typename... T>
 FMT_DEPRECATED inline auto printf(basic_string_view<wchar_t> fmt,
                                   const T&... args) -> int {
   return vfprintf(stdout, fmt, make_wprintf_args(args...));
 }
 
 FMT_END_EXPORT
 FMT_END_NAMESPACE
 
 #endif  // FMT_PRINTF_H_

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