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Diffstat (limited to 'src/zstd/zlibWrapper/zstd_zlibwrapper.h')
-rw-r--r-- | src/zstd/zlibWrapper/zstd_zlibwrapper.h | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/src/zstd/zlibWrapper/zstd_zlibwrapper.h b/src/zstd/zlibWrapper/zstd_zlibwrapper.h new file mode 100644 index 000000000..e791043e1 --- /dev/null +++ b/src/zstd/zlibWrapper/zstd_zlibwrapper.h @@ -0,0 +1,88 @@ +/* + * Copyright (c) 2016-2020, Przemyslaw Skibinski, 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. + */ + +#ifndef ZSTD_ZLIBWRAPPER_H +#define ZSTD_ZLIBWRAPPER_H + +#if defined (__cplusplus) +extern "C" { +#endif + + +#define ZLIB_CONST +#define Z_PREFIX +#define ZLIB_INTERNAL /* disables gz*64 functions but fixes zlib 1.2.4 with Z_PREFIX */ +#include <zlib.h> + +#if !defined(z_const) + #define z_const +#endif + + +/* returns a string with version of zstd library */ +const char * zstdVersion(void); + + +/*** COMPRESSION ***/ +/* ZWRAP_useZSTDcompression() enables/disables zstd compression during runtime. + By default zstd compression is disabled. To enable zstd compression please use one of the methods: + - compilation with the additional option -DZWRAP_USE_ZSTD=1 + - using '#define ZWRAP_USE_ZSTD 1' in source code before '#include "zstd_zlibwrapper.h"' + - calling ZWRAP_useZSTDcompression(1) + All above-mentioned methods will enable zstd compression for all threads. + Be aware that ZWRAP_useZSTDcompression() is not thread-safe and may lead to a race condition. */ +void ZWRAP_useZSTDcompression(int turn_on); + +/* checks if zstd compression is turned on */ +int ZWRAP_isUsingZSTDcompression(void); + +/* Changes a pledged source size for a given compression stream. + It will change ZSTD compression parameters what may improve compression speed and/or ratio. + The function should be called just after deflateInit() or deflateReset() and before deflate() or deflateSetDictionary(). + It's only helpful when data is compressed in blocks. + There will be no change in case of deflateInit() or deflateReset() immediately followed by deflate(strm, Z_FINISH) + as this case is automatically detected. */ +int ZWRAP_setPledgedSrcSize(z_streamp strm, unsigned long long pledgedSrcSize); + +/* Similar to deflateReset but preserves dictionary set using deflateSetDictionary. + It should improve compression speed because there will be less calls to deflateSetDictionary + When using zlib compression this method redirects to deflateReset. */ +int ZWRAP_deflateReset_keepDict(z_streamp strm); + + + +/*** DECOMPRESSION ***/ +typedef enum { ZWRAP_FORCE_ZLIB, ZWRAP_AUTO } ZWRAP_decompress_type; + +/* ZWRAP_setDecompressionType() enables/disables automatic recognition of zstd/zlib compressed data during runtime. + By default auto-detection of zstd and zlib streams in enabled (ZWRAP_AUTO). + Forcing zlib decompression with ZWRAP_setDecompressionType(ZWRAP_FORCE_ZLIB) slightly improves + decompression speed of zlib-encoded streams. + Be aware that ZWRAP_setDecompressionType() is not thread-safe and may lead to a race condition. */ +void ZWRAP_setDecompressionType(ZWRAP_decompress_type type); + +/* checks zstd decompression type */ +ZWRAP_decompress_type ZWRAP_getDecompressionType(void); + +/* Checks if zstd decompression is used for a given stream. + If will return 1 only when inflate() was called and zstd header was detected. */ +int ZWRAP_isUsingZSTDdecompression(z_streamp strm); + +/* Similar to inflateReset but preserves dictionary set using inflateSetDictionary. + inflate() will return Z_NEED_DICT only for the first time what will improve decompression speed. + For zlib streams this method redirects to inflateReset. */ +int ZWRAP_inflateReset_keepDict(z_streamp strm); + + +#if defined (__cplusplus) +} +#endif + +#endif /* ZSTD_ZLIBWRAPPER_H */ |