Mercurial > hg
view contrib/python-zstandard/zstd/deprecated/zbuff_compress.c @ 51370:0d414fb8336f
cleanup: remove unnecessary list constructor calls around list comprehensions
author | Manuel Jacob <me@manueljacob.de> |
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date | Fri, 02 Feb 2024 03:39:37 +0100 |
parents | b1fb341d8a61 |
children |
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/* * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. * All rights reserved. * * This source code is licensed under both the BSD-style license (found in the * LICENSE file in the root directory of this source tree) and the GPLv2 (found * in the COPYING file in the root directory of this source tree). * You may select, at your option, one of the above-listed licenses. */ /* ************************************* * Dependencies ***************************************/ #define ZBUFF_STATIC_LINKING_ONLY #include "zbuff.h" /*-*********************************************************** * Streaming compression * * A ZBUFF_CCtx object is required to track streaming operation. * Use ZBUFF_createCCtx() and ZBUFF_freeCCtx() to create/release resources. * Use ZBUFF_compressInit() to start a new compression operation. * ZBUFF_CCtx objects can be reused multiple times. * * Use ZBUFF_compressContinue() repetitively to consume your input. * *srcSizePtr and *dstCapacityPtr can be any size. * The function will report how many bytes were read or written by modifying *srcSizePtr and *dstCapacityPtr. * Note that it may not consume the entire input, in which case it's up to the caller to call again the function with remaining input. * The content of dst will be overwritten (up to *dstCapacityPtr) at each function call, so save its content if it matters or change dst . * @return : a hint to preferred nb of bytes to use as input for next function call (it's only a hint, to improve latency) * or an error code, which can be tested using ZBUFF_isError(). * * ZBUFF_compressFlush() can be used to instruct ZBUFF to compress and output whatever remains within its buffer. * Note that it will not output more than *dstCapacityPtr. * Therefore, some content might still be left into its internal buffer if dst buffer is too small. * @return : nb of bytes still present into internal buffer (0 if it's empty) * or an error code, which can be tested using ZBUFF_isError(). * * ZBUFF_compressEnd() instructs to finish a frame. * It will perform a flush and write frame epilogue. * Similar to ZBUFF_compressFlush(), it may not be able to output the entire internal buffer content if *dstCapacityPtr is too small. * @return : nb of bytes still present into internal buffer (0 if it's empty) * or an error code, which can be tested using ZBUFF_isError(). * * Hint : recommended buffer sizes (not compulsory) * input : ZSTD_BLOCKSIZE_MAX (128 KB), internal unit size, it improves latency to use this value. * output : ZSTD_compressBound(ZSTD_BLOCKSIZE_MAX) + ZSTD_blockHeaderSize + ZBUFF_endFrameSize : ensures it's always possible to write/flush/end a full block at best speed. * ***********************************************************/ ZBUFF_CCtx* ZBUFF_createCCtx(void) { return ZSTD_createCStream(); } ZBUFF_CCtx* ZBUFF_createCCtx_advanced(ZSTD_customMem customMem) { return ZSTD_createCStream_advanced(customMem); } size_t ZBUFF_freeCCtx(ZBUFF_CCtx* zbc) { return ZSTD_freeCStream(zbc); } /* ====== Initialization ====== */ size_t ZBUFF_compressInit_advanced(ZBUFF_CCtx* zbc, const void* dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize) { if (pledgedSrcSize==0) pledgedSrcSize = ZSTD_CONTENTSIZE_UNKNOWN; /* preserve "0 == unknown" behavior */ return ZSTD_initCStream_advanced(zbc, dict, dictSize, params, pledgedSrcSize); } size_t ZBUFF_compressInitDictionary(ZBUFF_CCtx* zbc, const void* dict, size_t dictSize, int compressionLevel) { return ZSTD_initCStream_usingDict(zbc, dict, dictSize, compressionLevel); } size_t ZBUFF_compressInit(ZBUFF_CCtx* zbc, int compressionLevel) { return ZSTD_initCStream(zbc, compressionLevel); } /* ====== Compression ====== */ size_t ZBUFF_compressContinue(ZBUFF_CCtx* zbc, void* dst, size_t* dstCapacityPtr, const void* src, size_t* srcSizePtr) { size_t result; ZSTD_outBuffer outBuff; ZSTD_inBuffer inBuff; outBuff.dst = dst; outBuff.pos = 0; outBuff.size = *dstCapacityPtr; inBuff.src = src; inBuff.pos = 0; inBuff.size = *srcSizePtr; result = ZSTD_compressStream(zbc, &outBuff, &inBuff); *dstCapacityPtr = outBuff.pos; *srcSizePtr = inBuff.pos; return result; } /* ====== Finalize ====== */ size_t ZBUFF_compressFlush(ZBUFF_CCtx* zbc, void* dst, size_t* dstCapacityPtr) { size_t result; ZSTD_outBuffer outBuff; outBuff.dst = dst; outBuff.pos = 0; outBuff.size = *dstCapacityPtr; result = ZSTD_flushStream(zbc, &outBuff); *dstCapacityPtr = outBuff.pos; return result; } size_t ZBUFF_compressEnd(ZBUFF_CCtx* zbc, void* dst, size_t* dstCapacityPtr) { size_t result; ZSTD_outBuffer outBuff; outBuff.dst = dst; outBuff.pos = 0; outBuff.size = *dstCapacityPtr; result = ZSTD_endStream(zbc, &outBuff); *dstCapacityPtr = outBuff.pos; return result; } /* ************************************* * Tool functions ***************************************/ size_t ZBUFF_recommendedCInSize(void) { return ZSTD_CStreamInSize(); } size_t ZBUFF_recommendedCOutSize(void) { return ZSTD_CStreamOutSize(); }