/*
* Copyright (C) 2003-2011 The Music Player Daemon Project
* http://www.musicpd.org
*
* 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 of the License, 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; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef MPD_PCM_UTILS_H
#define MPD_PCM_UTILS_H
#include "gcc.h"
#include <limits>
#include <stdint.h>
/**
* Add a byte count to the specified pointer. This is a utility
* function to convert a source pointer and a byte count to an "end"
* pointer for use in loops.
*/
template<typename T>
static inline const T *
pcm_end_pointer(const T *p, size_t size)
{
return (const T *)((const uint8_t *)p + size);
}
/**
* Check if the value is within the range of the provided bit size,
* and caps it if necessary.
*/
static inline int32_t
pcm_range(int32_t sample, unsigned bits)
{
if (gcc_unlikely(sample < (-1 << (bits - 1))))
return -1 << (bits - 1);
if (gcc_unlikely(sample >= (1 << (bits - 1))))
return (1 << (bits - 1)) - 1;
return sample;
}
/**
* Check if the value is within the range of the provided bit size,
* and caps it if necessary.
*/
static inline int64_t
pcm_range_64(int64_t sample, unsigned bits)
{
if (gcc_unlikely(sample < ((int64_t)-1 << (bits - 1))))
return (int64_t)-1 << (bits - 1);
if (gcc_unlikely(sample >= ((int64_t)1 << (bits - 1))))
return ((int64_t)1 << (bits - 1)) - 1;
return sample;
}
template<typename T, typename U, unsigned bits>
gcc_const
static inline T
PcmClamp(U x)
{
constexpr U MIN_VALUE = -(1 << (bits - 1));
constexpr U MAX_VALUE = (1 << (bits - 1)) - 1;
typedef std::numeric_limits<T> limits;
static_assert(MIN_VALUE >= limits::min(), "out of range");
static_assert(MAX_VALUE <= limits::max(), "out of range");
if (gcc_unlikely(x < MIN_VALUE))
return T(MIN_VALUE);
if (gcc_unlikely(x > MAX_VALUE))
return T(MAX_VALUE);
return T(x);
}
gcc_const
static inline int16_t
pcm_clamp_16(int x)
{
return PcmClamp<int16_t, int, 16>(x);
}
gcc_const
static inline int32_t
pcm_clamp_24(int x)
{
return PcmClamp<int32_t, int, 24>(x);
}
#endif
