87 lines
3.7 KiB
C++
87 lines
3.7 KiB
C++
/*
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* Copyright (C) 2008 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef SkPackBits_DEFINED
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#define SkPackBits_DEFINED
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#include "SkTypes.h"
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class SkPackBits {
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public:
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/** Given the number of 16bit values that will be passed to Pack16,
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returns the worst-case size needed for the dst[] buffer.
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*/
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static size_t ComputeMaxSize16(int count);
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/** Given the number of 8bit values that will be passed to Pack8,
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returns the worst-case size needed for the dst[] buffer.
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*/
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static size_t ComputeMaxSize8(int count);
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/** Write the src array into a packed format. The packing process may end
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up writing more bytes than it read, so dst[] must be large enough.
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@param src Input array of 16bit values
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@param count Number of entries in src[]
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@param dst Buffer (allocated by caller) to write the packed data
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into
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@return the number of bytes written to dst[]
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*/
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static size_t Pack16(const uint16_t src[], int count, uint8_t dst[]);
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/** Write the src array into a packed format. The packing process may end
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up writing more bytes than it read, so dst[] must be large enough.
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@param src Input array of 8bit values
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@param count Number of entries in src[]
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@param dst Buffer (allocated by caller) to write the packed data
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into
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@return the number of bytes written to dst[]
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*/
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static size_t Pack8(const uint8_t src[], int count, uint8_t dst[]);
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/** Unpack the data in src[], and expand it into dst[]. The src[] data was
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written by a previous call to Pack16.
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@param src Input data to unpack, previously created by Pack16.
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@param srcSize Number of bytes of src to unpack
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@param dst Buffer (allocated by caller) to expand the src[] into.
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@return the number of dst elements (not bytes) written into dst.
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*/
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static int Unpack16(const uint8_t src[], size_t srcSize, uint16_t dst[]);
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/** Unpack the data in src[], and expand it into dst[]. The src[] data was
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written by a previous call to Pack8.
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@param src Input data to unpack, previously created by Pack8.
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@param srcSize Number of bytes of src to unpack
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@param dst Buffer (allocated by caller) to expand the src[] into.
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@return the number of bytes written into dst.
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*/
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static int Unpack8(const uint8_t src[], size_t srcSize, uint8_t dst[]);
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/** Unpack the data from src[], skip the first dstSkip bytes, then write
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dstWrite bytes into dst[]. The src[] data was written by a previous
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call to Pack8. Return the number of bytes actually writtten into dst[]
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@param src Input data to unpack, previously created by Pack8.
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@param dst Buffer (allocated by caller) to expand the src[] into.
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@param dstSkip Number of bytes of unpacked src to skip before writing
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into dst
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@param dstWrite Number of bytes of unpacked src to write into dst (after
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skipping dstSkip bytes)
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*/
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static void Unpack8(uint8_t dst[], size_t dstSkip, size_t dstWrite,
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const uint8_t src[]);
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};
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#endif
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