monero/contrib/epee/include/hex.h
Lee Clagett 4a8f96f95d Improvements for epee binary to hex functions:
- Performance improvements
  - Added `span` for zero-copy pointer+length arguments
  - Added `std::ostream` overload for direct writing to output buffers
  - Removal of unused `string_tools::buff_to_hex`
2017-04-11 16:35:00 -04:00

78 lines
2.9 KiB
C++

// Copyright (c) 2017, The Monero Project
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
// conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
// of conditions and the following disclaimer in the documentation and/or other
// materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be
// used to endorse or promote products derived from this software without specific
// prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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#pragma once
#include <array>
#include <cstdint>
#include <iosfwd>
#include <string>
#include "span_view.h"
namespace epee
{
struct to_hex
{
//! \return A std::string containing hex of `src`.
static std::string string(const view<std::uint8_t> src);
//! \return A std::string containing hex of `src`.
static std::string string(const view<char> src) {
return string(view_cast<std::uint8_t>(src));
}
//! \return An array containing hex of `src`.
template<std::size_t N>
static std::array<char, N * 2>
array(const std::array<std::uint8_t, N>& src) noexcept(noexcept(view<std::uint8_t>(src)))
{
std::array<char, N * 2> out{{}};
static_assert(N <= 128, "keep the stack size down");
buffer_unchecked(out.data(), src);
return out;
}
//! Append `src` as hex to `out`.
static void buffer(std::ostream& out, const view<std::uint8_t> src);
//! Append `< + src + >` as hex to `out`.
static void formatted(std::ostream& out, const view<std::uint8_t> src);
//! Append `< + src + >` as hex to `out`.
template<typename T>
static void formatted_from_pod(std::ostream& out, const T& pod)
{
formatted(out, pod_cast<const std::uint8_t>(pod));
}
private:
//! Write `src` bytes as hex to `out`. `out` must be twice the length
static void buffer_unchecked(char* out, const view<std::uint8_t> src) noexcept;
};
}