portapack-mayhem/firmware/common/convert.hpp
Kyle Reed d29826e6f2
Update playlist file parsing, reduce allocs (#1157)
* Update playlist file parsing, reduce allocs
* Cleanup, move impl to cpp
2023-06-15 22:15:26 +02:00

47 lines
1.6 KiB
C++

/*
* Copyright (C) 2023 Kyle Reed
*
* This file is part of PortaPack.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifndef __CONVERT_H__
#define __CONVERT_H__
#include <charconv>
#include <cstdlib>
#include <string>
#include <string_view>
#include <type_traits>
/* Zero-allocation conversion helper. */
/* Notes:
* - T must be an integer type.
* - For base 16, input _must not_ contain a '0x' or '0X' prefix.
* - For base 8 a leading 0 on the literal is allowed.
* - Leading whitespce will cause the parse to fail.
*/
// TODO: from_chars seems to cause code bloat.
// Look into using strtol and friends instead.
template <typename T>
std::enable_if_t<std::is_integral_v<T>, bool> parse_int(std::string_view str, T& out_val, int base = 10) {
auto result = std::from_chars(str.data(), str.data() + str.length(), out_val, base);
return static_cast<int>(result.ec) == 0;
}
#endif /*__CONVERT_H__*/