chore: initial commit (extracted from Launchers monorepo)
Plugin: ns7zip v2.0.0 Architectures: x86-ansi, x86-unicode, amd64-unicode License: LGPL-2.1-or-later
This commit is contained in:
@@ -0,0 +1,225 @@
|
||||
// BitlDecoder.h -- the Least Significant Bit of byte is First
|
||||
|
||||
#ifndef ZIP7_INC_BITL_DECODER_H
|
||||
#define ZIP7_INC_BITL_DECODER_H
|
||||
|
||||
#include "../../../C/CpuArch.h"
|
||||
|
||||
#include "../IStream.h"
|
||||
|
||||
namespace NBitl {
|
||||
|
||||
const unsigned kNumBigValueBits = 8 * 4;
|
||||
const unsigned kNumValueBytes = 3;
|
||||
const unsigned kNumValueBits = 8 * kNumValueBytes;
|
||||
const UInt32 kMask = (1 << kNumValueBits) - 1;
|
||||
|
||||
#if !defined(Z7_BITL_USE_REVERSE_BITS_TABLE)
|
||||
#if 1 && defined(MY_CPU_ARM_OR_ARM64) \
|
||||
&& (defined(MY_CPU_ARM64) || defined(__ARM_ARCH_6T2__) \
|
||||
|| defined(__ARM_ARCH) && (__ARM_ARCH >= 7)) \
|
||||
&& (defined(__GNUC__) && (__GNUC__ >= 4) \
|
||||
|| defined(__clang__) && (__clang_major__ >= 4))
|
||||
#define Z7_BITL_USE_REVERSE_BITS_INSTRUCTION
|
||||
#elif 1
|
||||
#define Z7_BITL_USE_REVERSE_BITS_TABLE
|
||||
#endif
|
||||
#endif
|
||||
|
||||
#if defined(Z7_BITL_USE_REVERSE_BITS_TABLE)
|
||||
extern Byte kReverseTable[256];
|
||||
#endif
|
||||
|
||||
inline unsigned ReverseBits8(unsigned i)
|
||||
{
|
||||
#if defined(Z7_BITL_USE_REVERSE_BITS_TABLE)
|
||||
return kReverseTable[i];
|
||||
#elif defined(Z7_BITL_USE_REVERSE_BITS_INSTRUCTION)
|
||||
// rbit is available in ARMv6T2 and above
|
||||
asm ("rbit "
|
||||
#if defined(MY_CPU_ARM)
|
||||
"%0,%0" // it uses default register size,
|
||||
// but we need 32-bit register here.
|
||||
// we must use it only if default register size is 32-bit.
|
||||
// it will work incorrectly for ARM64.
|
||||
#else
|
||||
"%w0,%w0" // it uses 32-bit registers in ARM64.
|
||||
// compiler for (MY_CPU_ARM) can't compile it.
|
||||
#endif
|
||||
: "+r" (i));
|
||||
return i >> 24;
|
||||
#else
|
||||
unsigned
|
||||
x = ((i & 0x55) << 1) | ((i >> 1) & 0x55);
|
||||
x = ((x & 0x33) << 2) | ((x >> 2) & 0x33);
|
||||
return ((x & 0x0f) << 4) | (x >> 4);
|
||||
#endif
|
||||
}
|
||||
|
||||
|
||||
/* TInByte must support "Extra Bytes" (bytes that can be read after the end of stream
|
||||
TInByte::ReadByte() returns 0xFF after the end of stream
|
||||
TInByte::NumExtraBytes contains the number "Extra Bytes"
|
||||
|
||||
Bitl decoder can read up to 4 bytes ahead to internal buffer. */
|
||||
|
||||
template<class TInByte>
|
||||
class CBaseDecoder
|
||||
{
|
||||
protected:
|
||||
unsigned _bitPos;
|
||||
UInt32 _value;
|
||||
TInByte _stream;
|
||||
public:
|
||||
bool Create(UInt32 bufSize) { return _stream.Create(bufSize); }
|
||||
void SetStream(ISequentialInStream *inStream) { _stream.SetStream(inStream); }
|
||||
void ClearStreamPtr() { _stream.ClearStreamPtr(); }
|
||||
void Init()
|
||||
{
|
||||
_stream.Init();
|
||||
_bitPos = kNumBigValueBits;
|
||||
_value = 0;
|
||||
}
|
||||
|
||||
// the size of portion data in real stream that was already read from this object.
|
||||
// it doesn't include unused data in BitStream object buffer (up to 4 bytes)
|
||||
// it doesn't include unused data in TInByte buffers
|
||||
// it doesn't include virtual Extra bytes after the end of real stream data
|
||||
UInt64 GetStreamSize() const
|
||||
{
|
||||
return ExtraBitsWereRead() ?
|
||||
_stream.GetStreamSize():
|
||||
GetProcessedSize();
|
||||
}
|
||||
|
||||
// the size of virtual data that was read from this object.
|
||||
UInt64 GetProcessedSize() const { return _stream.GetProcessedSize() - ((kNumBigValueBits - _bitPos) >> 3); }
|
||||
|
||||
bool ThereAreDataInBitsBuffer() const { return this->_bitPos != kNumBigValueBits; }
|
||||
|
||||
Z7_FORCE_INLINE
|
||||
void Normalize()
|
||||
{
|
||||
for (; _bitPos >= 8; _bitPos -= 8)
|
||||
_value = ((UInt32)_stream.ReadByte() << (kNumBigValueBits - _bitPos)) | _value;
|
||||
}
|
||||
|
||||
Z7_FORCE_INLINE
|
||||
UInt32 ReadBits(unsigned numBits)
|
||||
{
|
||||
Normalize();
|
||||
UInt32 res = _value & ((1 << numBits) - 1);
|
||||
_bitPos += numBits;
|
||||
_value >>= numBits;
|
||||
return res;
|
||||
}
|
||||
|
||||
bool ExtraBitsWereRead() const
|
||||
{
|
||||
return (_stream.NumExtraBytes > 4 || kNumBigValueBits - _bitPos < (_stream.NumExtraBytes << 3));
|
||||
}
|
||||
|
||||
bool ExtraBitsWereRead_Fast() const
|
||||
{
|
||||
// full version is not inlined in vc6.
|
||||
// return _stream.NumExtraBytes != 0 && (_stream.NumExtraBytes > 4 || kNumBigValueBits - _bitPos < (_stream.NumExtraBytes << 3));
|
||||
|
||||
// (_stream.NumExtraBytes > 4) is fast overread detection. It's possible that
|
||||
// it doesn't return true, if small number of extra bits were read.
|
||||
return (_stream.NumExtraBytes > 4);
|
||||
}
|
||||
|
||||
// it must be fixed !!! with extra bits
|
||||
// UInt32 GetNumExtraBytes() const { return _stream.NumExtraBytes; }
|
||||
};
|
||||
|
||||
template<class TInByte>
|
||||
class CDecoder: public CBaseDecoder<TInByte>
|
||||
{
|
||||
UInt32 _normalValue;
|
||||
|
||||
public:
|
||||
void Init()
|
||||
{
|
||||
CBaseDecoder<TInByte>::Init();
|
||||
_normalValue = 0;
|
||||
}
|
||||
|
||||
Z7_FORCE_INLINE
|
||||
void Normalize()
|
||||
{
|
||||
for (; this->_bitPos >= 8; this->_bitPos -= 8)
|
||||
{
|
||||
const unsigned b = this->_stream.ReadByte();
|
||||
_normalValue = ((UInt32)b << (kNumBigValueBits - this->_bitPos)) | _normalValue;
|
||||
this->_value = (this->_value << 8) | ReverseBits8(b);
|
||||
}
|
||||
}
|
||||
|
||||
Z7_FORCE_INLINE
|
||||
UInt32 GetValue(unsigned numBits)
|
||||
{
|
||||
Normalize();
|
||||
return ((this->_value >> (8 - this->_bitPos)) & kMask) >> (kNumValueBits - numBits);
|
||||
}
|
||||
|
||||
Z7_FORCE_INLINE
|
||||
UInt32 GetValue_InHigh32bits()
|
||||
{
|
||||
Normalize();
|
||||
return this->_value << this->_bitPos;
|
||||
}
|
||||
|
||||
Z7_FORCE_INLINE
|
||||
void MovePos(size_t numBits)
|
||||
{
|
||||
this->_bitPos += (unsigned)numBits;
|
||||
_normalValue >>= numBits;
|
||||
}
|
||||
|
||||
Z7_FORCE_INLINE
|
||||
UInt32 ReadBits(unsigned numBits)
|
||||
{
|
||||
Normalize();
|
||||
UInt32 res = _normalValue & ((1 << numBits) - 1);
|
||||
MovePos(numBits);
|
||||
return res;
|
||||
}
|
||||
|
||||
void AlignToByte() { MovePos((32 - this->_bitPos) & 7); }
|
||||
|
||||
Z7_FORCE_INLINE
|
||||
Byte ReadDirectByte() { return this->_stream.ReadByte(); }
|
||||
|
||||
Z7_FORCE_INLINE
|
||||
size_t ReadDirectBytesPart(Byte *buf, size_t size) { return this->_stream.ReadBytesPart(buf, size); }
|
||||
|
||||
Z7_FORCE_INLINE
|
||||
Byte ReadAlignedByte()
|
||||
{
|
||||
if (this->_bitPos == kNumBigValueBits)
|
||||
return this->_stream.ReadByte();
|
||||
Byte b = (Byte)(_normalValue & 0xFF);
|
||||
MovePos(8);
|
||||
return b;
|
||||
}
|
||||
|
||||
// call it only if the object is aligned for byte.
|
||||
Z7_FORCE_INLINE
|
||||
bool ReadAlignedByte_FromBuf(Byte &b)
|
||||
{
|
||||
if (this->_stream.NumExtraBytes != 0)
|
||||
if (this->_stream.NumExtraBytes >= 4
|
||||
|| kNumBigValueBits - this->_bitPos <= (this->_stream.NumExtraBytes << 3))
|
||||
return false;
|
||||
if (this->_bitPos == kNumBigValueBits)
|
||||
return this->_stream.ReadByte_FromBuf(b);
|
||||
b = (Byte)(_normalValue & 0xFF);
|
||||
MovePos(8);
|
||||
return true;
|
||||
}
|
||||
};
|
||||
|
||||
}
|
||||
|
||||
#endif
|
||||
Reference in New Issue
Block a user