2024-01-25 11:21:15 +08:00

222 lines
12 KiB
C++

#pragma once
/*
==============================================================================
This file is part of the JUCE library.
Copyright (c) 2022 - Raw Material Software Limited
JUCE is an open source library subject to commercial or open-source
licensing.
The code included in this file is provided under the terms of the ISC license
http://www.isc.org/downloads/software-support-policy/isc-license. Permission
To use, copy, modify, and/or distribute this software for any purpose with or
without fee is hereby granted provided that the above copyright notice and
this permission notice appear in all copies.
JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
DISCLAIMED.
==============================================================================
*/
#if ! defined (DOXYGEN) && (JUCE_MAC || JUCE_IOS)
#include <libkern/OSByteOrder.h>
#endif
//==============================================================================
/** Contains static methods for converting the byte order between different
endiannesses.
@tags{Core}
*/
class FByteOrder
{
public:
//==============================================================================
/** Swaps the upper and lower bytes of a 16-bit integer. */
constexpr static uint16 swap (uint16 value) noexcept;
/** Swaps the upper and lower bytes of a 16-bit integer. */
constexpr static int16 swap (int16 value) noexcept;
/** Reverses the order of the 4 bytes in a 32-bit integer. */
static uint32 swap (uint32 value) noexcept;
/** Reverses the order of the 4 bytes in a 32-bit integer. */
static int32 swap (int32 value) noexcept;
/** Reverses the order of the 8 bytes in a 64-bit integer. */
static uint64 swap (uint64 value) noexcept;
/** Reverses the order of the 8 bytes in a 64-bit integer. */
static int64 swap (int64 value) noexcept;
/** Returns a garbled float which has the reverse byte-order of the original. */
static float swap (float value) noexcept;
/** Returns a garbled double which has the reverse byte-order of the original. */
static double swap (double value) noexcept;
//==============================================================================
/** Swaps the byte order of a signed or unsigned integer if the CPU is big-endian */
template <typename Type>
static Type swapIfBigEndian (Type value) noexcept
{
#if JUCE_LITTLE_ENDIAN
return value;
#else
return swap (value);
#endif
}
/** Swaps the byte order of a signed or unsigned integer if the CPU is little-endian */
template <typename Type>
static Type swapIfLittleEndian (Type value) noexcept
{
#if JUCE_LITTLE_ENDIAN
return swap (value);
#else
return value;
#endif
}
//==============================================================================
/** Turns 4 bytes into a little-endian integer. */
constexpr static uint32 littleEndianInt (const void* bytes) noexcept;
/** Turns 8 bytes into a little-endian integer. */
constexpr static uint64 littleEndianInt64 (const void* bytes) noexcept;
/** Turns 2 bytes into a little-endian integer. */
constexpr static uint16 littleEndianShort (const void* bytes) noexcept;
/** Converts 3 little-endian bytes into a signed 24-bit value (which is sign-extended to 32 bits). */
constexpr static int littleEndian24Bit (const void* bytes) noexcept;
/** Copies a 24-bit number to 3 little-endian bytes. */
static void littleEndian24BitToChars (int32 value, void* destBytes) noexcept;
//==============================================================================
/** Turns 4 bytes into a big-endian integer. */
constexpr static uint32 bigEndianInt (const void* bytes) noexcept;
/** Turns 8 bytes into a big-endian integer. */
constexpr static uint64 bigEndianInt64 (const void* bytes) noexcept;
/** Turns 2 bytes into a big-endian integer. */
constexpr static uint16 bigEndianShort (const void* bytes) noexcept;
/** Converts 3 big-endian bytes into a signed 24-bit value (which is sign-extended to 32 bits). */
constexpr static int bigEndian24Bit (const void* bytes) noexcept;
/** Copies a 24-bit number to 3 big-endian bytes. */
static void bigEndian24BitToChars (int32 value, void* destBytes) noexcept;
//==============================================================================
/** Constructs a 16-bit integer from its constituent bytes, in order of significance. */
constexpr static uint16 makeInt (uint8 leastSig, uint8 mostSig) noexcept;
/** Constructs a 32-bit integer from its constituent bytes, in order of significance. */
constexpr static uint32 makeInt (uint8 leastSig, uint8 byte1, uint8 byte2, uint8 mostSig) noexcept;
/** Constructs a 64-bit integer from its constituent bytes, in order of significance. */
constexpr static uint64 makeInt (uint8 leastSig, uint8 byte1, uint8 byte2, uint8 byte3,
uint8 byte4, uint8 byte5, uint8 byte6, uint8 mostSig) noexcept;
//==============================================================================
/** Returns true if the current CPU is big-endian. */
constexpr static bool isBigEndian() noexcept
{
#if JUCE_LITTLE_ENDIAN
return false;
#else
return true;
#endif
}
private:
FByteOrder() = delete;
};
//==============================================================================
constexpr inline uint16 FByteOrder::swap (uint16 v) noexcept { return static_cast<uint16> ((v << 8) | (v >> 8)); }
constexpr inline int16 FByteOrder::swap (int16 v) noexcept { return static_cast<int16> (swap (static_cast<uint16> (v))); }
inline int32 FByteOrder::swap (int32 v) noexcept { return static_cast<int32> (swap (static_cast<uint32> (v))); }
inline int64 FByteOrder::swap (int64 v) noexcept { return static_cast<int64> (swap (static_cast<uint64> (v))); }
inline float FByteOrder::swap (float v) noexcept { union { uint32 asUInt; float asFloat; } n; n.asFloat = v; n.asUInt = swap (n.asUInt); return n.asFloat; }
inline double FByteOrder::swap (double v) noexcept { union { uint64 asUInt; double asFloat; } n; n.asFloat = v; n.asUInt = swap (n.asUInt); return n.asFloat; }
#if JUCE_MSVC && ! defined (__INTEL_COMPILER)
#pragma intrinsic (_byteswap_ulong)
#endif
inline uint32 FByteOrder::swap (uint32 n) noexcept
{
#if JUCE_MAC || JUCE_IOS
return OSSwapInt32 (n);
#elif (JUCE_GCC || JUCE_CLANG) && JUCE_INTEL && ! JUCE_NO_INLINE_ASM
asm("bswap %%eax" : "=a"(n) : "a"(n));
return n;
#elif JUCE_MSVC
return _byteswap_ulong (n);
#elif JUCE_ANDROID
return bswap_32 (n);
#else
return (n << 24) | (n >> 24) | ((n & 0xff00) << 8) | ((n & 0xff0000) >> 8);
#endif
}
inline uint64 FByteOrder::swap (uint64 value) noexcept
{
#if JUCE_MAC || JUCE_IOS
return OSSwapInt64 (value);
#elif JUCE_MSVC
return _byteswap_uint64 (value);
#else
return (((uint64) swap ((uint32) value)) << 32) | swap ((uint32) (value >> 32));
#endif
}
constexpr inline uint16 FByteOrder::makeInt (uint8 b0, uint8 b1) noexcept
{
return static_cast<uint16> (static_cast<uint16> (b0) | (static_cast<uint16> (b1) << 8));
}
constexpr inline uint32 FByteOrder::makeInt (uint8 b0, uint8 b1, uint8 b2, uint8 b3) noexcept
{
return static_cast<uint32> (b0) | (static_cast<uint32> (b1) << 8)
| (static_cast<uint32> (b2) << 16) | (static_cast<uint32> (b3) << 24);
}
constexpr inline uint64 FByteOrder::makeInt (uint8 b0, uint8 b1, uint8 b2, uint8 b3, uint8 b4, uint8 b5, uint8 b6, uint8 b7) noexcept
{
return static_cast<uint64> (b0) | (static_cast<uint64> (b1) << 8) | (static_cast<uint64> (b2) << 16) | (static_cast<uint64> (b3) << 24)
| (static_cast<uint64> (b4) << 32) | (static_cast<uint64> (b5) << 40) | (static_cast<uint64> (b6) << 48) | (static_cast<uint64> (b7) << 56);
}
constexpr inline uint16 FByteOrder::littleEndianShort (const void* bytes) noexcept { return makeInt (static_cast<const uint8*> (bytes)[0], static_cast<const uint8*> (bytes)[1]); }
constexpr inline uint32 FByteOrder::littleEndianInt (const void* bytes) noexcept { return makeInt (static_cast<const uint8*> (bytes)[0], static_cast<const uint8*> (bytes)[1],
static_cast<const uint8*> (bytes)[2], static_cast<const uint8*> (bytes)[3]); }
constexpr inline uint64 FByteOrder::littleEndianInt64 (const void* bytes) noexcept { return makeInt (static_cast<const uint8*> (bytes)[0], static_cast<const uint8*> (bytes)[1],
static_cast<const uint8*> (bytes)[2], static_cast<const uint8*> (bytes)[3],
static_cast<const uint8*> (bytes)[4], static_cast<const uint8*> (bytes)[5],
static_cast<const uint8*> (bytes)[6], static_cast<const uint8*> (bytes)[7]); }
constexpr inline uint16 FByteOrder::bigEndianShort (const void* bytes) noexcept { return makeInt (static_cast<const uint8*> (bytes)[1], static_cast<const uint8*> (bytes)[0]); }
constexpr inline uint32 FByteOrder::bigEndianInt (const void* bytes) noexcept { return makeInt (static_cast<const uint8*> (bytes)[3], static_cast<const uint8*> (bytes)[2],
static_cast<const uint8*> (bytes)[1], static_cast<const uint8*> (bytes)[0]); }
constexpr inline uint64 FByteOrder::bigEndianInt64 (const void* bytes) noexcept { return makeInt (static_cast<const uint8*> (bytes)[7], static_cast<const uint8*> (bytes)[6],
static_cast<const uint8*> (bytes)[5], static_cast<const uint8*> (bytes)[4],
static_cast<const uint8*> (bytes)[3], static_cast<const uint8*> (bytes)[2],
static_cast<const uint8*> (bytes)[1], static_cast<const uint8*> (bytes)[0]); }
constexpr inline int32 FByteOrder::littleEndian24Bit (const void* bytes) noexcept { return (int32) ((((uint32) static_cast<const int8*> (bytes)[2]) << 16) | (((uint32) static_cast<const uint8*> (bytes)[1]) << 8) | ((uint32) static_cast<const uint8*> (bytes)[0])); }
constexpr inline int32 FByteOrder::bigEndian24Bit (const void* bytes) noexcept { return (int32) ((((uint32) static_cast<const int8*> (bytes)[0]) << 16) | (((uint32) static_cast<const uint8*> (bytes)[1]) << 8) | ((uint32) static_cast<const uint8*> (bytes)[2])); }
inline void FByteOrder::littleEndian24BitToChars (int32 value, void* destBytes) noexcept { static_cast<uint8*> (destBytes)[0] = (uint8) value; static_cast<uint8*> (destBytes)[1] = (uint8) (value >> 8); static_cast<uint8*> (destBytes)[2] = (uint8) (value >> 16); }
inline void FByteOrder::bigEndian24BitToChars (int32 value, void* destBytes) noexcept { static_cast<uint8*> (destBytes)[0] = (uint8) (value >> 16); static_cast<uint8*> (destBytes)[1] = (uint8) (value >> 8); static_cast<uint8*> (destBytes)[2] = (uint8) value; }