diff options
| author | simon <none@none> | 2014-05-07 13:19:05 -0700 | 
|---|---|---|
| committer | simon <none@none> | 2014-05-07 13:19:05 -0700 | 
| commit | dc4c184696b308b8f60fa1dd751b35e22bd47d62 (patch) | |
| tree | 1606d992f1cce6fe19572042c456725eb95d7066 /indra/llcommon/llbitpack.h | |
| parent | 883467a3cc421fca68a25589114e0e3f0538ff0e (diff) | |
| parent | 250db74bf9325acdc1169f6c13d297e7fe44b753 (diff) | |
Merge downstream version 3.7.8 code
Diffstat (limited to 'indra/llcommon/llbitpack.h')
| -rwxr-xr-x | indra/llcommon/llbitpack.h | 208 | 
1 files changed, 208 insertions, 0 deletions
| diff --git a/indra/llcommon/llbitpack.h b/indra/llcommon/llbitpack.h new file mode 100755 index 0000000000..f99a354cd4 --- /dev/null +++ b/indra/llcommon/llbitpack.h @@ -0,0 +1,208 @@ +/**  + * @file llbitpack.h + * @brief Convert data to packed bit stream + * + * $LicenseInfo:firstyear=2000&license=viewerlgpl$ + * Second Life Viewer Source Code + * Copyright (C) 2010, Linden Research, Inc. + *  + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; + * version 2.1 of the License only. + *  + * This library 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 + * Lesser General Public License for more details. + *  + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA + *  + * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA + * $/LicenseInfo$ + */ + +#ifndef LL_BITPACK_H +#define LL_BITPACK_H + +#include "llerror.h" + +const U32 MAX_DATA_BITS = 8; + + +class LLBitPack +{ +public: +	LLBitPack(U8 *buffer, U32 max_size) : mBuffer(buffer), mBufferSize(0), mLoad(0), mLoadSize(0), mTotalBits(0), mMaxSize(max_size) +	{ +	} + +	~LLBitPack() +	{ +	} + +	void resetBitPacking() +	{ +		mLoad = 0; +		mLoadSize = 0; +		mTotalBits = 0; +		mBufferSize = 0; +	} + +	U32 bitPack(U8 *total_data, U32 total_dsize) +	{ +		U32 dsize; +		U8 data; + +		while (total_dsize > 0) +		{ +			if (total_dsize > MAX_DATA_BITS) +			{ +				dsize = MAX_DATA_BITS; +				total_dsize -= MAX_DATA_BITS; +			} +			else +			{ +				dsize = total_dsize; +				total_dsize = 0; +			} + +			data = *total_data++; + +			data <<= (MAX_DATA_BITS - dsize); +			while (dsize > 0)  +			{ +				if (mLoadSize == MAX_DATA_BITS)  +				{ +					*(mBuffer + mBufferSize++) = mLoad; +					if (mBufferSize > mMaxSize) +					{ +						LL_ERRS() << "mBufferSize exceeding mMaxSize!" << LL_ENDL; +					} +					mLoadSize = 0; +					mLoad = 0x00; +				} +				mLoad <<= 1;			 +				mLoad |= (data >> (MAX_DATA_BITS - 1)); +				data <<= 1; +				mLoadSize++; +				mTotalBits++; +				dsize--; +			} +		} +		return mBufferSize; +	} + +	U32 bitCopy(U8 *total_data, U32 total_dsize) +	{ +		U32 dsize; +		U8  data; + +		while (total_dsize > 0) +		{ +			if (total_dsize > MAX_DATA_BITS) +			{ +				dsize = MAX_DATA_BITS; +				total_dsize -= MAX_DATA_BITS; +			} +			else +			{ +				dsize = total_dsize; +				total_dsize = 0; +			} + +			data = *total_data++; + +			while (dsize > 0)  +			{ +				if (mLoadSize == MAX_DATA_BITS)  +				{ +					*(mBuffer + mBufferSize++) = mLoad; +					if (mBufferSize > mMaxSize) +					{ +						LL_ERRS() << "mBufferSize exceeding mMaxSize!" << LL_ENDL; +					} +					mLoadSize = 0; +					mLoad = 0x00; +				} +				mLoad <<= 1;			 +				mLoad |= (data >> (MAX_DATA_BITS - 1)); +				data <<= 1; +				mLoadSize++; +				mTotalBits++; +				dsize--; +			} +		} +		return mBufferSize; +	} + +	U32 bitUnpack(U8 *total_retval, U32 total_dsize) +	{ +		U32 dsize; +		U8	*retval; + +		while (total_dsize > 0) +		{ +			if (total_dsize > MAX_DATA_BITS) +			{ +				dsize = MAX_DATA_BITS; +				total_dsize -= MAX_DATA_BITS; +			} +			else +			{ +				dsize = total_dsize; +				total_dsize = 0; +			} + +			retval = total_retval++; +			*retval = 0x00; +			while (dsize > 0)  +			{ +				if (mLoadSize == 0)  +				{ +#ifdef _DEBUG +					if (mBufferSize > mMaxSize) +					{ +						LL_ERRS() << "mBufferSize exceeding mMaxSize" << LL_ENDL; +						LL_ERRS() << mBufferSize << " > " << mMaxSize << LL_ENDL; +					} +#endif +					mLoad = *(mBuffer + mBufferSize++); +					mLoadSize = MAX_DATA_BITS; +				} +				*retval <<= 1; +				*retval |= (mLoad >> (MAX_DATA_BITS - 1)); +				mLoadSize--; +				mLoad <<= 1; +				dsize--; +			} +		} +		return mBufferSize; +	} + +	U32 flushBitPack() +	{ +		if (mLoadSize)  +		{ +			mLoad <<= (MAX_DATA_BITS - mLoadSize); +			*(mBuffer + mBufferSize++) = mLoad; +			if (mBufferSize > mMaxSize) +			{ +				LL_ERRS() << "mBufferSize exceeding mMaxSize!" << LL_ENDL; +			} +			mLoadSize = 0; +		} +		return mBufferSize; +	} + +	U8		*mBuffer; +	U32		mBufferSize; +	U8		mLoad; +	U32		mLoadSize; +	U32		mTotalBits; +	U32		mMaxSize; +}; + +#endif | 
