internal::decimal_formatter Class Reference

#include <format.h>

Inheritance diagram for internal::decimal_formatter:

Public Member Functions
	decimal_formatter (char *buf)
template<unsigned N>
char *	on (uint32_t u)

Private Member Functions
void	write_pair (unsigned N, uint32_t index)

Private Attributes
char *	buffer_

Detailed Description

Definition at line 847 of file format.h.

Constructor & Destructor Documentation

internal::decimal_formatter::decimal_formatter ( char *  buf )

inlineexplicit

Definition at line 856 of file format.h.

: buffer_(buf) {}

Member Function Documentation

template<unsigned N>

char* internal::decimal_formatter::on ( uint32_t  u )

inline

Definition at line 858 of file format.h.

                                             {
    if (N == 0) {
      *buffer_ = static_cast<char>(u) + '0';
    } else if (N == 1) {
      write_pair(0, u);
    } else {
      // The idea of using 4.32 fixed-point numbers is based on
      // https://github.com/jeaiii/itoa
      unsigned n = N - 1;
      unsigned a = n / 5 * n * 53 / 16;
      uint64_t t = ((1ULL << (32 + a)) /
                   data::ZERO_OR_POWERS_OF_10_32[n] + 1 - n / 9);
      t = ((t * u) >> a) + n / 5 * 4;
      write_pair(0, t >> 32);
      for (unsigned i = 2; i < N; i += 2) {
        t = 100ULL * static_cast<uint32_t>(t);
        write_pair(i, t >> 32);
      }
      if (N % 2 == 0) {
        buffer_[N] = static_cast<char>(
          (10ULL * static_cast<uint32_t>(t)) >> 32) + '0';
      }
    }
    return buffer_ += N + 1;
  }

void internal::decimal_formatter::write_pair ( unsigned  N, uint32_t  index  )

inlineprivate

Definition at line 851 of file format.h.

                                              {
    std::memcpy(buffer_ + N, data::DIGITS + index * 2, 2);
  }

Member Data Documentation

char* internal::decimal_formatter::buffer_

private

Definition at line 849 of file format.h.

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The documentation for this class was generated from the following file:

• wire-cell-build/util/inc/spdlog/fmt/bundled/format.h