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libwinpr-utils: convert BitStream to macros

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This commit is contained in:
Marc-André Moreau 2014-03-11 22:17:31 -04:00
parent 85049299e0
commit c2d8486d8a
2 changed files with 140 additions and 51 deletions
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85
winpr/include/winpr/bitstream.h
View File

@ -46,15 +46,88 @@ typedef struct _wBitStream wBitStream;
extern "C" {
#endif
WINPR_API void BitStream_Attach(wBitStream* bs, BYTE* buffer, UINT32 capacity);
WINPR_API void BitStream_Write_Bits(wBitStream* bs, UINT32 bits, UINT32 nbits);
WINPR_API void BitStream_Flush(wBitStream* bs);
WINPR_API void BitStream_Prefetch(wBitStream* bs);
WINPR_API void BitStream_Fetch(wBitStream* bs);
WINPR_API void BitStream_Shift(wBitStream* bs, UINT32 nbits);
#define BitStream_Prefetch(_bs) do { \
(_bs->prefetch) = 0; \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 4)) \
(_bs->prefetch) |= (*(_bs->pointer + 4) << 24); \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 5)) \
(_bs->prefetch) |= (*(_bs->pointer + 5) << 16); \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 6)) \
(_bs->prefetch) |= (*(_bs->pointer + 6) << 8); \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 7)) \
(_bs->prefetch) |= (*(_bs->pointer + 7) << 0); \
} while(0)
#define BitStream_Fetch(_bs) do { \
(_bs->accumulator) = 0; \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 0)) \
(_bs->accumulator) |= (*(_bs->pointer + 0) << 24); \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 1)) \
(_bs->accumulator) |= (*(_bs->pointer + 1) << 16); \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 2)) \
(_bs->accumulator) |= (*(_bs->pointer + 2) << 8); \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 3)) \
(_bs->accumulator) |= (*(_bs->pointer + 3) << 0); \
BitStream_Prefetch(_bs); \
} while(0)
#define BitStream_Flush(_bs) do { \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 0)) \
*(_bs->pointer + 0) = (_bs->accumulator >> 24); \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 1)) \
*(_bs->pointer + 1) = (_bs->accumulator >> 16); \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 2)) \
*(_bs->pointer + 2) = (_bs->accumulator >> 8); \
if ((_bs->pointer - _bs->buffer) < (_bs->capacity + 3)) \
*(_bs->pointer + 3) = (_bs->accumulator >> 0); \
} while(0)
#define BitStream_Shift(_bs, _nbits) do { \
_bs->accumulator <<= _nbits; \
_bs->position += _nbits; \
_bs->offset += _nbits; \
if (_bs->offset < 32) { \
_bs->mask = ((1 << _nbits) - 1); \
_bs->accumulator |= ((_bs->prefetch >> (32 - _nbits)) & _bs->mask); \
_bs->prefetch <<= _nbits; \
} else { \
_bs->mask = ((1 << _nbits) - 1); \
_bs->accumulator |= ((_bs->prefetch >> (32 - _nbits)) & _bs->mask); \
_bs->prefetch <<= _nbits; \
_bs->offset -= 32; \
_bs->pointer += 4; \
BitStream_Prefetch(_bs); \
if (_bs->offset) { \
_bs->mask = ((1 << _bs->offset) - 1); \
_bs->accumulator |= ((_bs->prefetch >> (32 - _bs->offset)) & _bs->mask); \
_bs->prefetch <<= _bs->offset; \
} \
} \
} while(0)
#define BitStream_Write_Bits(_bs, _bits, _nbits) do { \
_bs->position += _nbits; \
_bs->offset += _nbits; \
if (_bs->offset < 32) { \
_bs->accumulator |= (_bits << (32 - _bs->offset)); \
} else { \
_bs->offset -= 32; \
_bs->mask = ((1 << (_nbits - _bs->offset)) - 1); \
_bs->accumulator |= ((_bits >> _bs->offset) & _bs->mask); \
BitStream_Flush(bs); \
_bs->accumulator = 0; \
_bs->pointer += 4; \
if (_bs->offset) { \
_bs->mask = ((1 << _bs->offset) - 1); \
_bs->accumulator |= ((_bits & _bs->mask) << (32 - _bs->offset)); \
} \
} \
} while(0)
WINPR_API void BitDump(const BYTE* buffer, UINT32 length, UINT32 flags);
WINPR_API void BitStream_Attach(wBitStream* bs, BYTE* buffer, UINT32 capacity);
WINPR_API wBitStream* BitStream_New();
WINPR_API void BitStream_Free(wBitStream* bs);

106
winpr/libwinpr/utils/collections/BitStream.c
View File

@ -183,28 +183,19 @@ void BitDump(const BYTE* buffer, UINT32 length, UINT32 flags)
printf("\n");
}
void BitStream_Attach(wBitStream* bs, BYTE* buffer, UINT32 capacity)
{
bs->position = 0;
bs->buffer = buffer;
bs->offset = 0;
bs->accumulator = 0;
bs->pointer = bs->buffer;
bs->capacity = capacity;
bs->length = bs->capacity * 8;
}
#if 0
void BitStream_Flush(wBitStream* bs)
{
if ((bs->pointer - bs->buffer) < (bs->capacity + 0))
*(bs->pointer + 0) = (bs->accumulator >> 24);
if ((bs->pointer - bs->buffer) < (bs->capacity + 1))
*(bs->pointer + 1) = (bs->accumulator >> 16);
if ((bs->pointer - bs->buffer) < (bs->capacity + 2))
*(bs->pointer + 2) = (bs->accumulator >> 8);
if ((bs->pointer - bs->buffer) < (bs->capacity + 3))
*(bs->pointer + 3) = (bs->accumulator >> 0);
}
/**
* These are the original functions from which the macros are derived.
* Since it is much easier to develop and debug functions than macros,
* we keep a copy here for later improvements and modifications.
*/
WINPR_API void BitStream_Prefetch(wBitStream* bs);
WINPR_API void BitStream_Fetch(wBitStream* bs);
WINPR_API void BitStream_Flush(wBitStream* bs);
WINPR_API void BitStream_Shift(wBitStream* bs, UINT32 nbits);
WINPR_API void BitStream_Write_Bits(wBitStream* bs, UINT32 bits, UINT32 nbits);
void BitStream_Prefetch(wBitStream* bs)
{
@ -235,31 +226,16 @@ void BitStream_Fetch(wBitStream* bs)
BitStream_Prefetch(bs);
}
void BitStream_Write_Bits(wBitStream* bs, UINT32 bits, UINT32 nbits)
void BitStream_Flush(wBitStream* bs)
{
bs->position += nbits;
bs->offset += nbits;
if (bs->offset < 32)
{
bs->accumulator |= (bits << (32 - bs->offset));
}
else
{
bs->offset -= 32;
bs->mask = ((1 << (nbits - bs->offset)) - 1);
bs->accumulator |= ((bits >> bs->offset) & bs->mask);
BitStream_Flush(bs);
bs->accumulator = 0;
bs->pointer += 4;
if (bs->offset)
{
bs->mask = ((1 << bs->offset) - 1);
bs->accumulator |= ((bits & bs->mask) << (32 - bs->offset));
}
}
if ((bs->pointer - bs->buffer) < (bs->capacity + 0))
*(bs->pointer + 0) = (bs->accumulator >> 24);
if ((bs->pointer - bs->buffer) < (bs->capacity + 1))
*(bs->pointer + 1) = (bs->accumulator >> 16);
if ((bs->pointer - bs->buffer) < (bs->capacity + 2))
*(bs->pointer + 2) = (bs->accumulator >> 8);
if ((bs->pointer - bs->buffer) < (bs->capacity + 3))
*(bs->pointer + 3) = (bs->accumulator >> 0);
}
void BitStream_Shift(wBitStream* bs, UINT32 nbits)
@ -294,6 +270,46 @@ void BitStream_Shift(wBitStream* bs, UINT32 nbits)
}
}
void BitStream_Write_Bits(wBitStream* bs, UINT32 bits, UINT32 nbits)
{
bs->position += nbits;
bs->offset += nbits;
if (bs->offset < 32)
{
bs->accumulator |= (bits << (32 - bs->offset));
}
else
{
bs->offset -= 32;
bs->mask = ((1 << (nbits - bs->offset)) - 1);
bs->accumulator |= ((bits >> bs->offset) & bs->mask);
BitStream_Flush(bs);
bs->accumulator = 0;
bs->pointer += 4;
if (bs->offset)
{
bs->mask = ((1 << bs->offset) - 1);
bs->accumulator |= ((bits & bs->mask) << (32 - bs->offset));
}
}
}
#endif
void BitStream_Attach(wBitStream* bs, BYTE* buffer, UINT32 capacity)
{
bs->position = 0;
bs->buffer = buffer;
bs->offset = 0;
bs->accumulator = 0;
bs->pointer = bs->buffer;
bs->capacity = capacity;
bs->length = bs->capacity * 8;
}
wBitStream* BitStream_New()
{
wBitStream* bs = NULL;