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@@ -1,3160 +0,0 @@
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-/*
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- LZ4 - Fast LZ compression algorithm
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- Copyright (C) 2011-present, Yann Collet.
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-
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- BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
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-
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- Redistribution and use in source and binary forms, with or without
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- modification, are permitted provided that the following conditions are
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- met:
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-
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- * Redistributions of source code must retain the above copyright
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- notice, this list of conditions and the following disclaimer.
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- * Redistributions in binary form must reproduce the above
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- copyright notice, this list of conditions and the following disclaimer
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- in the documentation and/or other materials provided with the
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- distribution.
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-
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- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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- "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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- LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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- A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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- OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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- SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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- LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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- DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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- THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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- OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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-
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- You can contact the author at :
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- - LZ4 homepage : http://www.lz4.org
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- - LZ4 source repository : https://github.com/lz4/lz4
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-*/
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-
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-/*-************************************
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- * Tuning parameters
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- **************************************/
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-/*
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- * LZ4_HEAPMODE :
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- * Select how default compression functions will allocate memory for their hash table,
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- * in memory stack (0:default, fastest), or in memory heap (1:requires malloc()).
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- */
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-#include<arch/arch.h>
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-#if ARCH(I386) || ARCH(X86_64)
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-
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-#if ARCH(I386) || ARCH(X86_64)
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-#include <arch/x86_64/math/bitcount.h>
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-#else
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-#error Arch not supported.
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-#endif
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-
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-#ifndef LZ4_HEAPMODE
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-#define LZ4_HEAPMODE 0
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-#endif
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-
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-/*
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- * LZ4_ACCELERATION_DEFAULT :
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- * Select "acceleration" for LZ4_compress_fast() when parameter value <= 0
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- */
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-#define LZ4_ACCELERATION_DEFAULT 1
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-/*
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- * LZ4_ACCELERATION_MAX :
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- * Any "acceleration" value higher than this threshold
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- * get treated as LZ4_ACCELERATION_MAX instead (fix #876)
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- */
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-#define LZ4_ACCELERATION_MAX 65537
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-
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-/*-************************************
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- * CPU Feature Detection
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- **************************************/
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-/* LZ4_FORCE_MEMORY_ACCESS
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- * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable.
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- * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal.
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- * The below switch allow to select different access method for improved performance.
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- * Method 0 (default) : use `memcpy()`. Safe and portable.
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- * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable).
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- * This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`.
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- * Method 2 : direct access. This method is portable but violate C standard.
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- * It can generate buggy code on targets which assembly generation depends on alignment.
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- * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6)
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- * See https://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details.
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- * Prefer these methods in priority order (0 > 1 > 2)
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- */
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-#ifndef LZ4_FORCE_MEMORY_ACCESS /* can be defined externally */
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-#if defined(__GNUC__) && \
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- (defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__))
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-#define LZ4_FORCE_MEMORY_ACCESS 2
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-#elif (defined(__INTEL_COMPILER) && !defined(_WIN32)) || defined(__GNUC__)
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-#define LZ4_FORCE_MEMORY_ACCESS 1
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-#endif
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-#endif
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-
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-/*
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- * LZ4_FORCE_SW_BITCOUNT
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- * Define this parameter if your target system or compiler does not support hardware bit count
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- */
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-#if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for WinCE doesn't support Hardware bit count */
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-#undef LZ4_FORCE_SW_BITCOUNT /* avoid double def */
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-#define LZ4_FORCE_SW_BITCOUNT
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-#endif
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-
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-/*-************************************
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- * Dependency
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- **************************************/
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-/*
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- * LZ4_SRC_INCLUDED:
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- * Amalgamation flag, whether lz4.c is included
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- */
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-#ifndef LZ4_SRC_INCLUDED
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-#define LZ4_SRC_INCLUDED 1
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-#endif
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-
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-#ifndef LZ4_STATIC_LINKING_ONLY
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-#define LZ4_STATIC_LINKING_ONLY
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-#endif
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-
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-#ifndef LZ4_DISABLE_DEPRECATE_WARNINGS
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-#define LZ4_DISABLE_DEPRECATE_WARNINGS /* due to LZ4_decompress_safe_withPrefix64k */
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-#endif
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-
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-#define LZ4_STATIC_LINKING_ONLY /* LZ4_DISTANCE_MAX */
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-#include <common/lz4.h>
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-#include <common/glib.h>
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-/* see also "memory routines" below */
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-
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-/*-************************************
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- * Compiler Options
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- **************************************/
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-#if defined(_MSC_VER) && (_MSC_VER >= 1400) /* Visual Studio 2005+ */
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-#include <intrin.h> /* only present in VS2005+ */
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-#pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
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-#endif /* _MSC_VER */
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-
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-#ifndef LZ4_FORCE_INLINE
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-#ifdef _MSC_VER /* Visual Studio */
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-#define LZ4_FORCE_INLINE static __forceinline
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-#else
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-#if defined(__cplusplus) || defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
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-#ifdef __GNUC__
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-#define LZ4_FORCE_INLINE static inline __attribute__((always_inline))
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-#else
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-#define LZ4_FORCE_INLINE static inline
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-#endif
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-#else
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-#define LZ4_FORCE_INLINE static
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-#endif /* __STDC_VERSION__ */
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-#endif /* _MSC_VER */
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-#endif /* LZ4_FORCE_INLINE */
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-
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-/* LZ4_FORCE_O2 and LZ4_FORCE_INLINE
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- * gcc on ppc64le generates an unrolled SIMDized loop for LZ4_wildCopy8,
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- * together with a simple 8-byte copy loop as a fall-back path.
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- * However, this optimization hurts the decompression speed by >30%,
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- * because the execution does not go to the optimized loop
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- * for typical compressible data, and all of the preamble checks
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- * before going to the fall-back path become useless overhead.
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- * This optimization happens only with the -O3 flag, and -O2 generates
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- * a simple 8-byte copy loop.
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- * With gcc on ppc64le, all of the LZ4_decompress_* and LZ4_wildCopy8
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- * functions are annotated with __attribute__((optimize("O2"))),
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- * and also LZ4_wildCopy8 is forcibly inlined, so that the O2 attribute
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- * of LZ4_wildCopy8 does not affect the compression speed.
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- */
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-#if defined(__PPC64__) && defined(__LITTLE_ENDIAN__) && defined(__GNUC__) && !defined(__clang__)
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-#define LZ4_FORCE_O2 __attribute__((optimize("O2")))
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-#undef LZ4_FORCE_INLINE
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-#define LZ4_FORCE_INLINE static __inline __attribute__((optimize("O2"), always_inline))
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-#else
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-#define LZ4_FORCE_O2
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-#endif
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-
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-#if (defined(__GNUC__) && (__GNUC__ >= 3)) || (defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 800)) || defined(__clang__)
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-#define expect(expr, value) (__builtin_expect((expr), (value)))
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-#else
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-#define expect(expr, value) (expr)
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-#endif
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-
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-#ifndef likely
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-#define likely(expr) expect((expr) != 0, 1)
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-#endif
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-#ifndef unlikely
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-#define unlikely(expr) expect((expr) != 0, 0)
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-#endif
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-
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-/* Should the alignment test prove unreliable, for some reason,
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- * it can be disabled by setting LZ4_ALIGN_TEST to 0 */
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-#ifndef LZ4_ALIGN_TEST /* can be externally provided */
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-#define LZ4_ALIGN_TEST 1
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-#endif
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-
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-/*-************************************
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- * Memory routines
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- **************************************/
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-#ifdef LZ4_USER_MEMORY_FUNCTIONS
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-/* memory management functions can be customized by user project.
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- * Below functions must exist somewhere in the Project
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- * and be available at link time */
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-void *LZ4_malloc(size_t s);
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-void *LZ4_calloc(size_t n, size_t s);
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-void LZ4_free(void *p);
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-#define ALLOC(s) LZ4_malloc(s)
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-#define ALLOC_AND_ZERO(s) LZ4_calloc(1, s)
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-#define FREEMEM(p) LZ4_free(p)
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-#else
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-#include <mm/slab.h> /* malloc, calloc, free */
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-#define ALLOC(s) kmalloc(s, 0)
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-#define ALLOC_AND_ZERO(s) kzalloc(s, 0)
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-#define FREEMEM(p) kfree(p)
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-#endif
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-
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-#include <common/string.h> /* memset, memcpy */
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-#define MEM_INIT(p, v, s) memset((p), (v), (s))
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-
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-/*-************************************
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- * Common Constants
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- **************************************/
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-#define MINMATCH 4
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-
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-#define WILDCOPYLENGTH 8
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-#define LASTLITERALS 5 /* see ../doc/lz4_Block_format.md#parsing-restrictions */
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-#define MFLIMIT 12 /* see ../doc/lz4_Block_format.md#parsing-restrictions */
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-#define MATCH_SAFEGUARD_DISTANCE ((2 * WILDCOPYLENGTH) - MINMATCH) /* ensure it's possible to write 2 x wildcopyLength without overflowing output buffer */
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-#define FASTLOOP_SAFE_DISTANCE 64
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-static const int LZ4_minLength = (MFLIMIT + 1);
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-
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-#define KB *(1 << 10)
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-#define MB *(1 << 20)
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-#define GB *(1U << 30)
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-
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-#define LZ4_DISTANCE_ABSOLUTE_MAX 65535
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-#if (LZ4_DISTANCE_MAX > LZ4_DISTANCE_ABSOLUTE_MAX) /* max supported by LZ4 format */
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-#error "LZ4_DISTANCE_MAX is too big : must be <= 65535"
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-#endif
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-
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-#define ML_BITS 4
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-#define ML_MASK ((1U << ML_BITS) - 1)
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-#define RUN_BITS (8 - ML_BITS)
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-#define RUN_MASK ((1U << RUN_BITS) - 1)
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-
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-/*-************************************
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- * Error detection
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- **************************************/
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-#if defined(LZ4_DEBUG) && (LZ4_DEBUG >= 1)
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-#include <assert.h>
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-#else
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-#ifndef assert
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-#define assert(condition) ((void)0)
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-#endif
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-#endif
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-
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-#define LZ4_STATIC_ASSERT(c) \
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- { \
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- enum \
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- { \
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- LZ4_static_assert = 1 / (int)(!!(c)) \
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- }; \
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- } /* use after variable declarations */
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-
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-#if defined(LZ4_DEBUG) && (LZ4_DEBUG >= 2)
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-#include <stdio.h>
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-static int g_debuglog_enable = 1;
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-#define DEBUGLOG(l, ...) \
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- { \
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- if ((g_debuglog_enable) && (l <= LZ4_DEBUG)) \
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- { \
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- fprintf(stderr, __FILE__ ": "); \
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- fprintf(stderr, __VA_ARGS__); \
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- fprintf(stderr, " \n"); \
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- } \
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- }
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-#else
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-#define DEBUGLOG(l, ...) \
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- { \
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- } /* disabled */
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-#endif
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-
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-static int LZ4_isAligned(const void *ptr, size_t alignment)
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-{
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- return ((size_t)ptr & (alignment - 1)) == 0;
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-}
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-
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-/*-************************************
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- * Types
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- **************************************/
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-#include <limits.h>
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-#if defined(__cplusplus) || (defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
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-#include <DragonOS/stdint.h>
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-typedef uint8_t BYTE;
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-typedef uint16_t U16;
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-typedef uint32_t U32;
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-typedef int32_t S32;
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-typedef uint64_t U64;
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-typedef uintptr_t uptrval;
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-#else
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-#if UINT_MAX != 4294967295UL
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-#error "LZ4 code (when not C++ or C99) assumes that sizeof(int) == 4"
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-#endif
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-typedef unsigned char BYTE;
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-typedef unsigned short U16;
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-typedef unsigned int U32;
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-typedef signed int S32;
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-typedef unsigned long long U64;
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-typedef size_t uptrval; /* generally true, except OpenVMS-64 */
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-#endif
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-
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-#if defined(__x86_64__)
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-typedef U64 reg_t; /* 64-bits in x32 mode */
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-#else
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-typedef size_t reg_t; /* 32-bits in x32 mode */
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-#endif
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-
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-typedef enum
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-{
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- notLimited = 0,
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- limitedOutput = 1,
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- fillOutput = 2
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-} limitedOutput_directive;
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-
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-/*-************************************
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- * Reading and writing into memory
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- **************************************/
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-
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-/**
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- * LZ4 relies on memcpy with a constant size being inlined. In freestanding
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- * environments, the compiler can't assume the implementation of memcpy() is
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- * standard compliant, so it can't apply its specialized memcpy() inlining
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- * logic. When possible, use __builtin_memcpy() to tell the compiler to analyze
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- * memcpy() as if it were standard compliant, so it can inline it in freestanding
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- * environments. This is needed when decompressing the Linux Kernel, for example.
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- */
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-#define LZ4_memcpy(dst, src, size) memcpy(dst, src, size)
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-
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-static unsigned LZ4_isLittleEndian(void)
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-{
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- const union
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- {
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- U32 u;
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- BYTE c[4];
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- } one = {1}; /* don't use static : performance detrimental */
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- return one.c[0];
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-}
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-
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-#if defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS == 2)
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-/* lie to the compiler about data alignment; use with caution */
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-
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-static U16 LZ4_read16(const void *memPtr) { return *(const U16 *)memPtr; }
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-static U32 LZ4_read32(const void *memPtr) { return *(const U32 *)memPtr; }
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-static reg_t LZ4_read_ARCH(const void *memPtr) { return *(const reg_t *)memPtr; }
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-
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-static void LZ4_write16(void *memPtr, U16 value) { *(U16 *)memPtr = value; }
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-static void LZ4_write32(void *memPtr, U32 value) { *(U32 *)memPtr = value; }
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-
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-#elif defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS == 1)
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-
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-/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
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-/* currently only defined for gcc and icc */
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-typedef union
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-{
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- U16 u16;
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- U32 u32;
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- reg_t uArch;
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-} __attribute__((packed)) unalign;
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-
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-static U16 LZ4_read16(const void *ptr) { return ((const unalign *)ptr)->u16; }
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-static U32 LZ4_read32(const void *ptr) { return ((const unalign *)ptr)->u32; }
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-static reg_t LZ4_read_ARCH(const void *ptr) { return ((const unalign *)ptr)->uArch; }
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-
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-static void LZ4_write16(void *memPtr, U16 value) { ((unalign *)memPtr)->u16 = value; }
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-static void LZ4_write32(void *memPtr, U32 value) { ((unalign *)memPtr)->u32 = value; }
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-
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-#else /* safe and portable access using memcpy() */
|
|
|
-
|
|
|
-static U16 LZ4_read16(const void *memPtr)
|
|
|
-{
|
|
|
- U16 val;
|
|
|
- LZ4_memcpy(&val, memPtr, sizeof(val));
|
|
|
- return val;
|
|
|
-}
|
|
|
-
|
|
|
-static U32 LZ4_read32(const void *memPtr)
|
|
|
-{
|
|
|
- U32 val;
|
|
|
- LZ4_memcpy(&val, memPtr, sizeof(val));
|
|
|
- return val;
|
|
|
-}
|
|
|
-
|
|
|
-static reg_t LZ4_read_ARCH(const void *memPtr)
|
|
|
-{
|
|
|
- reg_t val;
|
|
|
- LZ4_memcpy(&val, memPtr, sizeof(val));
|
|
|
- return val;
|
|
|
-}
|
|
|
-
|
|
|
-static void LZ4_write16(void *memPtr, U16 value)
|
|
|
-{
|
|
|
- LZ4_memcpy(memPtr, &value, sizeof(value));
|
|
|
-}
|
|
|
-
|
|
|
-static void LZ4_write32(void *memPtr, U32 value)
|
|
|
-{
|
|
|
- LZ4_memcpy(memPtr, &value, sizeof(value));
|
|
|
-}
|
|
|
-
|
|
|
-#endif /* LZ4_FORCE_MEMORY_ACCESS */
|
|
|
-
|
|
|
-static U16 LZ4_readLE16(const void *memPtr)
|
|
|
-{
|
|
|
- if (LZ4_isLittleEndian())
|
|
|
- {
|
|
|
- return LZ4_read16(memPtr);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- const BYTE *p = (const BYTE *)memPtr;
|
|
|
- return (U16)((U16)p[0] + (p[1] << 8));
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-static void LZ4_writeLE16(void *memPtr, U16 value)
|
|
|
-{
|
|
|
- if (LZ4_isLittleEndian())
|
|
|
- {
|
|
|
- LZ4_write16(memPtr, value);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- BYTE *p = (BYTE *)memPtr;
|
|
|
- p[0] = (BYTE)value;
|
|
|
- p[1] = (BYTE)(value >> 8);
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-/* customized variant of memcpy, which can overwrite up to 8 bytes beyond dstEnd */
|
|
|
-LZ4_FORCE_INLINE
|
|
|
-void LZ4_wildCopy8(void *dstPtr, const void *srcPtr, void *dstEnd)
|
|
|
-{
|
|
|
- BYTE *d = (BYTE *)dstPtr;
|
|
|
- const BYTE *s = (const BYTE *)srcPtr;
|
|
|
- BYTE *const e = (BYTE *)dstEnd;
|
|
|
-
|
|
|
- do
|
|
|
- {
|
|
|
- LZ4_memcpy(d, s, 8);
|
|
|
- d += 8;
|
|
|
- s += 8;
|
|
|
- } while (d < e);
|
|
|
-}
|
|
|
-
|
|
|
-static const unsigned inc32table[8] = {0, 1, 2, 1, 0, 4, 4, 4};
|
|
|
-static const int dec64table[8] = {0, 0, 0, -1, -4, 1, 2, 3};
|
|
|
-
|
|
|
-#ifndef LZ4_FAST_DEC_LOOP
|
|
|
-#if defined __i386__ || defined _M_IX86 || defined __x86_64__ || defined _M_X64
|
|
|
-#define LZ4_FAST_DEC_LOOP 1
|
|
|
-#elif defined(__aarch64__) && !defined(__clang__)
|
|
|
-/* On aarch64, we disable this optimization for clang because on certain
|
|
|
- * mobile chipsets, performance is reduced with clang. For information
|
|
|
- * refer to https://github.com/lz4/lz4/pull/707 */
|
|
|
-#define LZ4_FAST_DEC_LOOP 1
|
|
|
-#else
|
|
|
-#define LZ4_FAST_DEC_LOOP 0
|
|
|
-#endif
|
|
|
-#endif
|
|
|
-
|
|
|
-#if LZ4_FAST_DEC_LOOP
|
|
|
-
|
|
|
-LZ4_FORCE_INLINE void
|
|
|
-LZ4_memcpy_using_offset_base(BYTE *dstPtr, const BYTE *srcPtr, BYTE *dstEnd, const size_t offset)
|
|
|
-{
|
|
|
- assert(srcPtr + offset == dstPtr);
|
|
|
- if (offset < 8)
|
|
|
- {
|
|
|
- LZ4_write32(dstPtr, 0); /* silence an msan warning when offset==0 */
|
|
|
- dstPtr[0] = srcPtr[0];
|
|
|
- dstPtr[1] = srcPtr[1];
|
|
|
- dstPtr[2] = srcPtr[2];
|
|
|
- dstPtr[3] = srcPtr[3];
|
|
|
- srcPtr += inc32table[offset];
|
|
|
- LZ4_memcpy(dstPtr + 4, srcPtr, 4);
|
|
|
- srcPtr -= dec64table[offset];
|
|
|
- dstPtr += 8;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- LZ4_memcpy(dstPtr, srcPtr, 8);
|
|
|
- dstPtr += 8;
|
|
|
- srcPtr += 8;
|
|
|
- }
|
|
|
-
|
|
|
- LZ4_wildCopy8(dstPtr, srcPtr, dstEnd);
|
|
|
-}
|
|
|
-
|
|
|
-/* customized variant of memcpy, which can overwrite up to 32 bytes beyond dstEnd
|
|
|
- * this version copies two times 16 bytes (instead of one time 32 bytes)
|
|
|
- * because it must be compatible with offsets >= 16. */
|
|
|
-LZ4_FORCE_INLINE void
|
|
|
-LZ4_wildCopy32(void *dstPtr, const void *srcPtr, void *dstEnd)
|
|
|
-{
|
|
|
- BYTE *d = (BYTE *)dstPtr;
|
|
|
- const BYTE *s = (const BYTE *)srcPtr;
|
|
|
- BYTE *const e = (BYTE *)dstEnd;
|
|
|
-
|
|
|
- do
|
|
|
- {
|
|
|
- LZ4_memcpy(d, s, 16);
|
|
|
- LZ4_memcpy(d + 16, s + 16, 16);
|
|
|
- d += 32;
|
|
|
- s += 32;
|
|
|
- } while (d < e);
|
|
|
-}
|
|
|
-
|
|
|
-/* LZ4_memcpy_using_offset() presumes :
|
|
|
- * - dstEnd >= dstPtr + MINMATCH
|
|
|
- * - there is at least 8 bytes available to write after dstEnd */
|
|
|
-LZ4_FORCE_INLINE void
|
|
|
-LZ4_memcpy_using_offset(BYTE *dstPtr, const BYTE *srcPtr, BYTE *dstEnd, const size_t offset)
|
|
|
-{
|
|
|
- BYTE v[8];
|
|
|
-
|
|
|
- assert(dstEnd >= dstPtr + MINMATCH);
|
|
|
-
|
|
|
- switch (offset)
|
|
|
- {
|
|
|
- case 1:
|
|
|
- MEM_INIT(v, *srcPtr, 8);
|
|
|
- break;
|
|
|
- case 2:
|
|
|
- LZ4_memcpy(v, srcPtr, 2);
|
|
|
- LZ4_memcpy(&v[2], srcPtr, 2);
|
|
|
- LZ4_memcpy(&v[4], v, 4);
|
|
|
- break;
|
|
|
- case 4:
|
|
|
- LZ4_memcpy(v, srcPtr, 4);
|
|
|
- LZ4_memcpy(&v[4], srcPtr, 4);
|
|
|
- break;
|
|
|
- default:
|
|
|
- LZ4_memcpy_using_offset_base(dstPtr, srcPtr, dstEnd, offset);
|
|
|
- return;
|
|
|
- }
|
|
|
-
|
|
|
- LZ4_memcpy(dstPtr, v, 8);
|
|
|
- dstPtr += 8;
|
|
|
- while (dstPtr < dstEnd)
|
|
|
- {
|
|
|
- LZ4_memcpy(dstPtr, v, 8);
|
|
|
- dstPtr += 8;
|
|
|
- }
|
|
|
-}
|
|
|
-#endif
|
|
|
-
|
|
|
-/*-************************************
|
|
|
- * Common functions
|
|
|
- **************************************/
|
|
|
-static unsigned LZ4_NbCommonBytes(reg_t val)
|
|
|
-{
|
|
|
- assert(val != 0);
|
|
|
- if (LZ4_isLittleEndian())
|
|
|
- {
|
|
|
- if (sizeof(val) == 8)
|
|
|
- {
|
|
|
-#if defined(_MSC_VER) && (_MSC_VER >= 1800) && defined(_M_AMD64) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
- /* x64 CPUS without BMI support interpret `TZCNT` as `REP BSF` */
|
|
|
- return (unsigned)_tzcnt_u64(val) >> 3;
|
|
|
-#elif defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
- unsigned long r = 0;
|
|
|
- _BitScanForward64(&r, (U64)val);
|
|
|
- return (unsigned)r >> 3;
|
|
|
-#elif (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \
|
|
|
- ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \
|
|
|
- !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
- return (unsigned)__builtin_ctzll((U64)val) >> 3;
|
|
|
-#else
|
|
|
- const U64 m = 0x0101010101010101ULL;
|
|
|
- val ^= val - 1;
|
|
|
- return (unsigned)(((U64)((val & (m - 1)) * m)) >> 56);
|
|
|
-#endif
|
|
|
- }
|
|
|
- else /* 32 bits */
|
|
|
- {
|
|
|
-#if defined(_MSC_VER) && (_MSC_VER >= 1400) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
- unsigned long r;
|
|
|
- _BitScanForward(&r, (U32)val);
|
|
|
- return (unsigned)r >> 3;
|
|
|
-#elif (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \
|
|
|
- ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \
|
|
|
- !defined(__TINYC__) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
- return (unsigned)__builtin_ctz((U32)val) >> 3;
|
|
|
-#else
|
|
|
- const U32 m = 0x01010101;
|
|
|
- return (unsigned)((((val - 1) ^ val) & (m - 1)) * m) >> 24;
|
|
|
-#endif
|
|
|
- }
|
|
|
- }
|
|
|
- else /* Big Endian CPU */
|
|
|
- {
|
|
|
- if (sizeof(val) == 8)
|
|
|
- {
|
|
|
-#if (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \
|
|
|
- ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \
|
|
|
- !defined(__TINYC__) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
- return (unsigned)__clzll((U64)val) >> 3;
|
|
|
-#else
|
|
|
-#if 1
|
|
|
- /* this method is probably faster,
|
|
|
- * but adds a 128 bytes lookup table */
|
|
|
- static const unsigned char ctz7_tab[128] = {
|
|
|
- 7,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 3,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 4,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 3,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 5,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 3,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 4,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 3,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 6,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 3,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 4,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 3,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 5,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 3,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 4,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 3,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- 2,
|
|
|
- 0,
|
|
|
- 1,
|
|
|
- 0,
|
|
|
- };
|
|
|
- U64 const mask = 0x0101010101010101ULL;
|
|
|
- U64 const t = (((val >> 8) - mask) | val) & mask;
|
|
|
- return ctz7_tab[(t * 0x0080402010080402ULL) >> 57];
|
|
|
-#else
|
|
|
- /* this method doesn't consume memory space like the previous one,
|
|
|
- * but it contains several branches,
|
|
|
- * that may end up slowing execution */
|
|
|
- static const U32 by32 = sizeof(val) * 4; /* 32 on 64 bits (goal), 16 on 32 bits.
|
|
|
- Just to avoid some static analyzer complaining about shift by 32 on 32-bits target.
|
|
|
- Note that this code path is never triggered in 32-bits mode. */
|
|
|
- unsigned r;
|
|
|
- if (!(val >> by32))
|
|
|
- {
|
|
|
- r = 4;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- r = 0;
|
|
|
- val >>= by32;
|
|
|
- }
|
|
|
- if (!(val >> 16))
|
|
|
- {
|
|
|
- r += 2;
|
|
|
- val >>= 8;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- val >>= 24;
|
|
|
- }
|
|
|
- r += (!val);
|
|
|
- return r;
|
|
|
-#endif
|
|
|
-#endif
|
|
|
- }
|
|
|
- else /* 32 bits */
|
|
|
- {
|
|
|
-#if (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) || \
|
|
|
- ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \
|
|
|
- !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
- return (unsigned)__clz((U32)val) >> 3;
|
|
|
-#else
|
|
|
- val >>= 8;
|
|
|
- val = ((((val + 0x00FFFF00) | 0x00FFFFFF) + val) |
|
|
|
- (val + 0x00FF0000)) >>
|
|
|
- 24;
|
|
|
- return (unsigned)val ^ 3;
|
|
|
-#endif
|
|
|
- }
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-#define STEPSIZE sizeof(reg_t)
|
|
|
-LZ4_FORCE_INLINE
|
|
|
-unsigned LZ4_count(const BYTE *pIn, const BYTE *pMatch, const BYTE *pInLimit)
|
|
|
-{
|
|
|
- const BYTE *const pStart = pIn;
|
|
|
-
|
|
|
- if (likely(pIn < pInLimit - (STEPSIZE - 1)))
|
|
|
- {
|
|
|
- reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
|
|
|
- if (!diff)
|
|
|
- {
|
|
|
- pIn += STEPSIZE;
|
|
|
- pMatch += STEPSIZE;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- return LZ4_NbCommonBytes(diff);
|
|
|
- }
|
|
|
- }
|
|
|
-
|
|
|
- while (likely(pIn < pInLimit - (STEPSIZE - 1)))
|
|
|
- {
|
|
|
- reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
|
|
|
- if (!diff)
|
|
|
- {
|
|
|
- pIn += STEPSIZE;
|
|
|
- pMatch += STEPSIZE;
|
|
|
- continue;
|
|
|
- }
|
|
|
- pIn += LZ4_NbCommonBytes(diff);
|
|
|
- return (unsigned)(pIn - pStart);
|
|
|
- }
|
|
|
-
|
|
|
- if ((STEPSIZE == 8) && (pIn < (pInLimit - 3)) && (LZ4_read32(pMatch) == LZ4_read32(pIn)))
|
|
|
- {
|
|
|
- pIn += 4;
|
|
|
- pMatch += 4;
|
|
|
- }
|
|
|
- if ((pIn < (pInLimit - 1)) && (LZ4_read16(pMatch) == LZ4_read16(pIn)))
|
|
|
- {
|
|
|
- pIn += 2;
|
|
|
- pMatch += 2;
|
|
|
- }
|
|
|
- if ((pIn < pInLimit) && (*pMatch == *pIn))
|
|
|
- pIn++;
|
|
|
- return (unsigned)(pIn - pStart);
|
|
|
-}
|
|
|
-
|
|
|
-#ifndef LZ4_COMMONDEFS_ONLY
|
|
|
-/*-************************************
|
|
|
- * Local Constants
|
|
|
- **************************************/
|
|
|
-static const int LZ4_64Klimit = ((64 KB) + (MFLIMIT - 1));
|
|
|
-static const U32 LZ4_skipTrigger = 6; /* Increase this value ==> compression run slower on incompressible data */
|
|
|
-
|
|
|
-/*-************************************
|
|
|
- * Local Structures and types
|
|
|
- **************************************/
|
|
|
-typedef enum
|
|
|
-{
|
|
|
- clearedTable = 0,
|
|
|
- byPtr,
|
|
|
- byU32,
|
|
|
- byU16
|
|
|
-} tableType_t;
|
|
|
-
|
|
|
-/**
|
|
|
- * This enum distinguishes several different modes of accessing previous
|
|
|
- * content in the stream.
|
|
|
- *
|
|
|
- * - noDict : There is no preceding content.
|
|
|
- * - withPrefix64k : Table entries up to ctx->dictSize before the current blob
|
|
|
- * blob being compressed are valid and refer to the preceding
|
|
|
- * content (of length ctx->dictSize), which is available
|
|
|
- * contiguously preceding in memory the content currently
|
|
|
- * being compressed.
|
|
|
- * - usingExtDict : Like withPrefix64k, but the preceding content is somewhere
|
|
|
- * else in memory, starting at ctx->dictionary with length
|
|
|
- * ctx->dictSize.
|
|
|
- * - usingDictCtx : Like usingExtDict, but everything concerning the preceding
|
|
|
- * content is in a separate context, pointed to by
|
|
|
- * ctx->dictCtx. ctx->dictionary, ctx->dictSize, and table
|
|
|
- * entries in the current context that refer to positions
|
|
|
- * preceding the beginning of the current compression are
|
|
|
- * ignored. Instead, ctx->dictCtx->dictionary and ctx->dictCtx
|
|
|
- * ->dictSize describe the location and size of the preceding
|
|
|
- * content, and matches are found by looking in the ctx
|
|
|
- * ->dictCtx->hashTable.
|
|
|
- */
|
|
|
-typedef enum
|
|
|
-{
|
|
|
- noDict = 0,
|
|
|
- withPrefix64k,
|
|
|
- usingExtDict,
|
|
|
- usingDictCtx
|
|
|
-} dict_directive;
|
|
|
-typedef enum
|
|
|
-{
|
|
|
- noDictIssue = 0,
|
|
|
- dictSmall
|
|
|
-} dictIssue_directive;
|
|
|
-
|
|
|
-/*-************************************
|
|
|
- * Local Utils
|
|
|
- **************************************/
|
|
|
-int LZ4_versionNumber(void) { return LZ4_VERSION_NUMBER; }
|
|
|
-const char *LZ4_versionString(void) { return LZ4_VERSION_STRING; }
|
|
|
-int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); }
|
|
|
-int LZ4_sizeofState(void) { return LZ4_STREAMSIZE; }
|
|
|
-
|
|
|
-/*-************************************
|
|
|
- * Internal Definitions used in Tests
|
|
|
- **************************************/
|
|
|
-#if defined(__cplusplus)
|
|
|
-extern "C"
|
|
|
-{
|
|
|
-#endif
|
|
|
-
|
|
|
- int LZ4_compress_forceExtDict(LZ4_stream_t *LZ4_dict, const char *source, char *dest, int srcSize);
|
|
|
-
|
|
|
- int LZ4_decompress_safe_forceExtDict(const char *source, char *dest,
|
|
|
- int compressedSize, int maxOutputSize,
|
|
|
- const void *dictStart, size_t dictSize);
|
|
|
-
|
|
|
-#if defined(__cplusplus)
|
|
|
-}
|
|
|
-#endif
|
|
|
-
|
|
|
-/*-******************************
|
|
|
- * Compression functions
|
|
|
- ********************************/
|
|
|
-LZ4_FORCE_INLINE U32 LZ4_hash4(U32 sequence, tableType_t const tableType)
|
|
|
-{
|
|
|
- if (tableType == byU16)
|
|
|
- return ((sequence * 2654435761U) >> ((MINMATCH * 8) - (LZ4_HASHLOG + 1)));
|
|
|
- else
|
|
|
- return ((sequence * 2654435761U) >> ((MINMATCH * 8) - LZ4_HASHLOG));
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_INLINE U32 LZ4_hash5(U64 sequence, tableType_t const tableType)
|
|
|
-{
|
|
|
- const U32 hashLog = (tableType == byU16) ? LZ4_HASHLOG + 1 : LZ4_HASHLOG;
|
|
|
- if (LZ4_isLittleEndian())
|
|
|
- {
|
|
|
- const U64 prime5bytes = 889523592379ULL;
|
|
|
- return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog));
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- const U64 prime8bytes = 11400714785074694791ULL;
|
|
|
- return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog));
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_INLINE U32 LZ4_hashPosition(const void *const p, tableType_t const tableType)
|
|
|
-{
|
|
|
- if ((sizeof(reg_t) == 8) && (tableType != byU16))
|
|
|
- return LZ4_hash5(LZ4_read_ARCH(p), tableType);
|
|
|
- return LZ4_hash4(LZ4_read32(p), tableType);
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_INLINE void LZ4_clearHash(U32 h, void *tableBase, tableType_t const tableType)
|
|
|
-{
|
|
|
- switch (tableType)
|
|
|
- {
|
|
|
- default: /* fallthrough */
|
|
|
- case clearedTable:
|
|
|
- { /* illegal! */
|
|
|
- assert(0);
|
|
|
- return;
|
|
|
- }
|
|
|
- case byPtr:
|
|
|
- {
|
|
|
- const BYTE **hashTable = (const BYTE **)tableBase;
|
|
|
- hashTable[h] = NULL;
|
|
|
- return;
|
|
|
- }
|
|
|
- case byU32:
|
|
|
- {
|
|
|
- U32 *hashTable = (U32 *)tableBase;
|
|
|
- hashTable[h] = 0;
|
|
|
- return;
|
|
|
- }
|
|
|
- case byU16:
|
|
|
- {
|
|
|
- U16 *hashTable = (U16 *)tableBase;
|
|
|
- hashTable[h] = 0;
|
|
|
- return;
|
|
|
- }
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_INLINE void LZ4_putIndexOnHash(U32 idx, U32 h, void *tableBase, tableType_t const tableType)
|
|
|
-{
|
|
|
- switch (tableType)
|
|
|
- {
|
|
|
- default: /* fallthrough */
|
|
|
- case clearedTable: /* fallthrough */
|
|
|
- case byPtr:
|
|
|
- { /* illegal! */
|
|
|
- assert(0);
|
|
|
- return;
|
|
|
- }
|
|
|
- case byU32:
|
|
|
- {
|
|
|
- U32 *hashTable = (U32 *)tableBase;
|
|
|
- hashTable[h] = idx;
|
|
|
- return;
|
|
|
- }
|
|
|
- case byU16:
|
|
|
- {
|
|
|
- U16 *hashTable = (U16 *)tableBase;
|
|
|
- assert(idx < 65536);
|
|
|
- hashTable[h] = (U16)idx;
|
|
|
- return;
|
|
|
- }
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_INLINE void LZ4_putPositionOnHash(const BYTE *p, U32 h,
|
|
|
- void *tableBase, tableType_t const tableType,
|
|
|
- const BYTE *srcBase)
|
|
|
-{
|
|
|
- switch (tableType)
|
|
|
- {
|
|
|
- case clearedTable:
|
|
|
- { /* illegal! */
|
|
|
- assert(0);
|
|
|
- return;
|
|
|
- }
|
|
|
- case byPtr:
|
|
|
- {
|
|
|
- const BYTE **hashTable = (const BYTE **)tableBase;
|
|
|
- hashTable[h] = p;
|
|
|
- return;
|
|
|
- }
|
|
|
- case byU32:
|
|
|
- {
|
|
|
- U32 *hashTable = (U32 *)tableBase;
|
|
|
- hashTable[h] = (U32)(p - srcBase);
|
|
|
- return;
|
|
|
- }
|
|
|
- case byU16:
|
|
|
- {
|
|
|
- U16 *hashTable = (U16 *)tableBase;
|
|
|
- hashTable[h] = (U16)(p - srcBase);
|
|
|
- return;
|
|
|
- }
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_INLINE void LZ4_putPosition(const BYTE *p, void *tableBase, tableType_t tableType, const BYTE *srcBase)
|
|
|
-{
|
|
|
- U32 const h = LZ4_hashPosition(p, tableType);
|
|
|
- LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
|
|
|
-}
|
|
|
-
|
|
|
-/* LZ4_getIndexOnHash() :
|
|
|
- * Index of match position registered in hash table.
|
|
|
- * hash position must be calculated by using base+index, or dictBase+index.
|
|
|
- * Assumption 1 : only valid if tableType == byU32 or byU16.
|
|
|
- * Assumption 2 : h is presumed valid (within limits of hash table)
|
|
|
- */
|
|
|
-LZ4_FORCE_INLINE U32 LZ4_getIndexOnHash(U32 h, const void *tableBase, tableType_t tableType)
|
|
|
-{
|
|
|
- LZ4_STATIC_ASSERT(LZ4_MEMORY_USAGE > 2);
|
|
|
- if (tableType == byU32)
|
|
|
- {
|
|
|
- const U32 *const hashTable = (const U32 *)tableBase;
|
|
|
- assert(h < (1U << (LZ4_MEMORY_USAGE - 2)));
|
|
|
- return hashTable[h];
|
|
|
- }
|
|
|
- if (tableType == byU16)
|
|
|
- {
|
|
|
- const U16 *const hashTable = (const U16 *)tableBase;
|
|
|
- assert(h < (1U << (LZ4_MEMORY_USAGE - 1)));
|
|
|
- return hashTable[h];
|
|
|
- }
|
|
|
- assert(0);
|
|
|
- return 0; /* forbidden case */
|
|
|
-}
|
|
|
-
|
|
|
-static const BYTE *LZ4_getPositionOnHash(U32 h, const void *tableBase, tableType_t tableType, const BYTE *srcBase)
|
|
|
-{
|
|
|
- if (tableType == byPtr)
|
|
|
- {
|
|
|
- const BYTE *const *hashTable = (const BYTE *const *)tableBase;
|
|
|
- return hashTable[h];
|
|
|
- }
|
|
|
- if (tableType == byU32)
|
|
|
- {
|
|
|
- const U32 *const hashTable = (const U32 *)tableBase;
|
|
|
- return hashTable[h] + srcBase;
|
|
|
- }
|
|
|
- {
|
|
|
- const U16 *const hashTable = (const U16 *)tableBase;
|
|
|
- return hashTable[h] + srcBase;
|
|
|
- } /* default, to ensure a return */
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_INLINE const BYTE *
|
|
|
-LZ4_getPosition(const BYTE *p,
|
|
|
- const void *tableBase, tableType_t tableType,
|
|
|
- const BYTE *srcBase)
|
|
|
-{
|
|
|
- U32 const h = LZ4_hashPosition(p, tableType);
|
|
|
- return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_INLINE void
|
|
|
-LZ4_prepareTable(LZ4_stream_t_internal *const cctx,
|
|
|
- const int inputSize,
|
|
|
- const tableType_t tableType)
|
|
|
-{
|
|
|
- /* If the table hasn't been used, it's guaranteed to be zeroed out, and is
|
|
|
- * therefore safe to use no matter what mode we're in. Otherwise, we figure
|
|
|
- * out if it's safe to leave as is or whether it needs to be reset.
|
|
|
- */
|
|
|
- if ((tableType_t)cctx->tableType != clearedTable)
|
|
|
- {
|
|
|
- assert(inputSize >= 0);
|
|
|
- if ((tableType_t)cctx->tableType != tableType || ((tableType == byU16) && cctx->currentOffset + (unsigned)inputSize >= 0xFFFFU) || ((tableType == byU32) && cctx->currentOffset > 1 GB) || tableType == byPtr || inputSize >= 4 KB)
|
|
|
- {
|
|
|
- DEBUGLOG(4, "LZ4_prepareTable: Resetting table in %p", cctx);
|
|
|
- MEM_INIT(cctx->hashTable, 0, LZ4_HASHTABLESIZE);
|
|
|
- cctx->currentOffset = 0;
|
|
|
- cctx->tableType = (U32)clearedTable;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- DEBUGLOG(4, "LZ4_prepareTable: Re-use hash table (no reset)");
|
|
|
- }
|
|
|
- }
|
|
|
-
|
|
|
- /* Adding a gap, so all previous entries are > LZ4_DISTANCE_MAX back, is faster
|
|
|
- * than compressing without a gap. However, compressing with
|
|
|
- * currentOffset == 0 is faster still, so we preserve that case.
|
|
|
- */
|
|
|
- if (cctx->currentOffset != 0 && tableType == byU32)
|
|
|
- {
|
|
|
- DEBUGLOG(5, "LZ4_prepareTable: adding 64KB to currentOffset");
|
|
|
- cctx->currentOffset += 64 KB;
|
|
|
- }
|
|
|
-
|
|
|
- /* Finally, clear history */
|
|
|
- cctx->dictCtx = NULL;
|
|
|
- cctx->dictionary = NULL;
|
|
|
- cctx->dictSize = 0;
|
|
|
-}
|
|
|
-
|
|
|
-/** LZ4_compress_generic() :
|
|
|
- * inlined, to ensure branches are decided at compilation time.
|
|
|
- * Presumed already validated at this stage:
|
|
|
- * - source != NULL
|
|
|
- * - inputSize > 0
|
|
|
- */
|
|
|
-LZ4_FORCE_INLINE int LZ4_compress_generic_validated(
|
|
|
- LZ4_stream_t_internal *const cctx,
|
|
|
- const char *const source,
|
|
|
- char *const dest,
|
|
|
- const int inputSize,
|
|
|
- int *inputConsumed, /* only written when outputDirective == fillOutput */
|
|
|
- const int maxOutputSize,
|
|
|
- const limitedOutput_directive outputDirective,
|
|
|
- const tableType_t tableType,
|
|
|
- const dict_directive dictDirective,
|
|
|
- const dictIssue_directive dictIssue,
|
|
|
- const int acceleration)
|
|
|
-{
|
|
|
- int result;
|
|
|
- const BYTE *ip = (const BYTE *)source;
|
|
|
-
|
|
|
- U32 const startIndex = cctx->currentOffset;
|
|
|
- const BYTE *base = (const BYTE *)source - startIndex;
|
|
|
- const BYTE *lowLimit;
|
|
|
-
|
|
|
- const LZ4_stream_t_internal *dictCtx = (const LZ4_stream_t_internal *)cctx->dictCtx;
|
|
|
- const BYTE *const dictionary =
|
|
|
- dictDirective == usingDictCtx ? dictCtx->dictionary : cctx->dictionary;
|
|
|
- const U32 dictSize =
|
|
|
- dictDirective == usingDictCtx ? dictCtx->dictSize : cctx->dictSize;
|
|
|
- const U32 dictDelta = (dictDirective == usingDictCtx) ? startIndex - dictCtx->currentOffset : 0; /* make indexes in dictCtx comparable with index in current context */
|
|
|
-
|
|
|
- int const maybe_extMem = (dictDirective == usingExtDict) || (dictDirective == usingDictCtx);
|
|
|
- U32 const prefixIdxLimit = startIndex - dictSize; /* used when dictDirective == dictSmall */
|
|
|
- const BYTE *const dictEnd = dictionary ? dictionary + dictSize : dictionary;
|
|
|
- const BYTE *anchor = (const BYTE *)source;
|
|
|
- const BYTE *const iend = ip + inputSize;
|
|
|
- const BYTE *const mflimitPlusOne = iend - MFLIMIT + 1;
|
|
|
- const BYTE *const matchlimit = iend - LASTLITERALS;
|
|
|
-
|
|
|
- /* the dictCtx currentOffset is indexed on the start of the dictionary,
|
|
|
- * while a dictionary in the current context precedes the currentOffset */
|
|
|
- const BYTE *dictBase = !dictionary ? NULL : (dictDirective == usingDictCtx) ? dictionary + dictSize - dictCtx->currentOffset
|
|
|
- : dictionary + dictSize - startIndex;
|
|
|
-
|
|
|
- BYTE *op = (BYTE *)dest;
|
|
|
- BYTE *const olimit = op + maxOutputSize;
|
|
|
-
|
|
|
- U32 offset = 0;
|
|
|
- U32 forwardH;
|
|
|
-
|
|
|
- DEBUGLOG(5, "LZ4_compress_generic_validated: srcSize=%i, tableType=%u", inputSize, tableType);
|
|
|
- assert(ip != NULL);
|
|
|
- /* If init conditions are not met, we don't have to mark stream
|
|
|
- * as having dirty context, since no action was taken yet */
|
|
|
- if (outputDirective == fillOutput && maxOutputSize < 1)
|
|
|
- {
|
|
|
- return 0;
|
|
|
- } /* Impossible to store anything */
|
|
|
- if ((tableType == byU16) && (inputSize >= LZ4_64Klimit))
|
|
|
- {
|
|
|
- return 0;
|
|
|
- } /* Size too large (not within 64K limit) */
|
|
|
- if (tableType == byPtr)
|
|
|
- assert(dictDirective == noDict); /* only supported use case with byPtr */
|
|
|
- assert(acceleration >= 1);
|
|
|
-
|
|
|
- lowLimit = (const BYTE *)source - (dictDirective == withPrefix64k ? dictSize : 0);
|
|
|
-
|
|
|
- /* Update context state */
|
|
|
- if (dictDirective == usingDictCtx)
|
|
|
- {
|
|
|
- /* Subsequent linked blocks can't use the dictionary. */
|
|
|
- /* Instead, they use the block we just compressed. */
|
|
|
- cctx->dictCtx = NULL;
|
|
|
- cctx->dictSize = (U32)inputSize;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- cctx->dictSize += (U32)inputSize;
|
|
|
- }
|
|
|
- cctx->currentOffset += (U32)inputSize;
|
|
|
- cctx->tableType = (U32)tableType;
|
|
|
-
|
|
|
- if (inputSize < LZ4_minLength)
|
|
|
- goto _last_literals; /* Input too small, no compression (all literals) */
|
|
|
-
|
|
|
- /* First Byte */
|
|
|
- LZ4_putPosition(ip, cctx->hashTable, tableType, base);
|
|
|
- ip++;
|
|
|
- forwardH = LZ4_hashPosition(ip, tableType);
|
|
|
-
|
|
|
- /* Main Loop */
|
|
|
- for (;;)
|
|
|
- {
|
|
|
- const BYTE *match;
|
|
|
- BYTE *token;
|
|
|
- const BYTE *filledIp;
|
|
|
-
|
|
|
- /* Find a match */
|
|
|
- if (tableType == byPtr)
|
|
|
- {
|
|
|
- const BYTE *forwardIp = ip;
|
|
|
- int step = 1;
|
|
|
- int searchMatchNb = acceleration << LZ4_skipTrigger;
|
|
|
- do
|
|
|
- {
|
|
|
- U32 const h = forwardH;
|
|
|
- ip = forwardIp;
|
|
|
- forwardIp += step;
|
|
|
- step = (searchMatchNb++ >> LZ4_skipTrigger);
|
|
|
-
|
|
|
- if (unlikely(forwardIp > mflimitPlusOne))
|
|
|
- goto _last_literals;
|
|
|
- assert(ip < mflimitPlusOne);
|
|
|
-
|
|
|
- match = LZ4_getPositionOnHash(h, cctx->hashTable, tableType, base);
|
|
|
- forwardH = LZ4_hashPosition(forwardIp, tableType);
|
|
|
- LZ4_putPositionOnHash(ip, h, cctx->hashTable, tableType, base);
|
|
|
-
|
|
|
- } while ((match + LZ4_DISTANCE_MAX < ip) || (LZ4_read32(match) != LZ4_read32(ip)));
|
|
|
- }
|
|
|
- else
|
|
|
- { /* byU32, byU16 */
|
|
|
-
|
|
|
- const BYTE *forwardIp = ip;
|
|
|
- int step = 1;
|
|
|
- int searchMatchNb = acceleration << LZ4_skipTrigger;
|
|
|
- do
|
|
|
- {
|
|
|
- U32 const h = forwardH;
|
|
|
- U32 const current = (U32)(forwardIp - base);
|
|
|
- U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType);
|
|
|
- assert(matchIndex <= current);
|
|
|
- assert(forwardIp - base < (ptrdiff_t)(2 GB - 1));
|
|
|
- ip = forwardIp;
|
|
|
- forwardIp += step;
|
|
|
- step = (searchMatchNb++ >> LZ4_skipTrigger);
|
|
|
-
|
|
|
- if (unlikely(forwardIp > mflimitPlusOne))
|
|
|
- goto _last_literals;
|
|
|
- assert(ip < mflimitPlusOne);
|
|
|
-
|
|
|
- if (dictDirective == usingDictCtx)
|
|
|
- {
|
|
|
- if (matchIndex < startIndex)
|
|
|
- {
|
|
|
- /* there was no match, try the dictionary */
|
|
|
- assert(tableType == byU32);
|
|
|
- matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32);
|
|
|
- match = dictBase + matchIndex;
|
|
|
- matchIndex += dictDelta; /* make dictCtx index comparable with current context */
|
|
|
- lowLimit = dictionary;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- match = base + matchIndex;
|
|
|
- lowLimit = (const BYTE *)source;
|
|
|
- }
|
|
|
- }
|
|
|
- else if (dictDirective == usingExtDict)
|
|
|
- {
|
|
|
- if (matchIndex < startIndex)
|
|
|
- {
|
|
|
- DEBUGLOG(7, "extDict candidate: matchIndex=%5u < startIndex=%5u", matchIndex, startIndex);
|
|
|
- assert(startIndex - matchIndex >= MINMATCH);
|
|
|
- match = dictBase + matchIndex;
|
|
|
- lowLimit = dictionary;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- match = base + matchIndex;
|
|
|
- lowLimit = (const BYTE *)source;
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- { /* single continuous memory segment */
|
|
|
- match = base + matchIndex;
|
|
|
- }
|
|
|
- forwardH = LZ4_hashPosition(forwardIp, tableType);
|
|
|
- LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType);
|
|
|
-
|
|
|
- DEBUGLOG(7, "candidate at pos=%u (offset=%u \n", matchIndex, current - matchIndex);
|
|
|
- if ((dictIssue == dictSmall) && (matchIndex < prefixIdxLimit))
|
|
|
- {
|
|
|
- continue;
|
|
|
- } /* match outside of valid area */
|
|
|
- assert(matchIndex < current);
|
|
|
- if (((tableType != byU16) || (LZ4_DISTANCE_MAX < LZ4_DISTANCE_ABSOLUTE_MAX)) && (matchIndex + LZ4_DISTANCE_MAX < current))
|
|
|
- {
|
|
|
- continue;
|
|
|
- } /* too far */
|
|
|
- assert((current - matchIndex) <= LZ4_DISTANCE_MAX); /* match now expected within distance */
|
|
|
-
|
|
|
- if (LZ4_read32(match) == LZ4_read32(ip))
|
|
|
- {
|
|
|
- if (maybe_extMem)
|
|
|
- offset = current - matchIndex;
|
|
|
- break; /* match found */
|
|
|
- }
|
|
|
-
|
|
|
- } while (1);
|
|
|
- }
|
|
|
-
|
|
|
- /* Catch up */
|
|
|
- filledIp = ip;
|
|
|
- while (((ip > anchor) & (match > lowLimit)) && (unlikely(ip[-1] == match[-1])))
|
|
|
- {
|
|
|
- ip--;
|
|
|
- match--;
|
|
|
- }
|
|
|
-
|
|
|
- /* Encode Literals */
|
|
|
- {
|
|
|
- unsigned const litLength = (unsigned)(ip - anchor);
|
|
|
- token = op++;
|
|
|
- if ((outputDirective == limitedOutput) && /* Check output buffer overflow */
|
|
|
- (unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength / 255) > olimit)))
|
|
|
- {
|
|
|
- return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */
|
|
|
- }
|
|
|
- if ((outputDirective == fillOutput) &&
|
|
|
- (unlikely(op + (litLength + 240) / 255 /* litlen */ + litLength /* literals */ + 2 /* offset */ + 1 /* token */ + MFLIMIT - MINMATCH /* min last literals so last match is <= end - MFLIMIT */ > olimit)))
|
|
|
- {
|
|
|
- op--;
|
|
|
- goto _last_literals;
|
|
|
- }
|
|
|
- if (litLength >= RUN_MASK)
|
|
|
- {
|
|
|
- int len = (int)(litLength - RUN_MASK);
|
|
|
- *token = (RUN_MASK << ML_BITS);
|
|
|
- for (; len >= 255; len -= 255)
|
|
|
- *op++ = 255;
|
|
|
- *op++ = (BYTE)len;
|
|
|
- }
|
|
|
- else
|
|
|
- *token = (BYTE)(litLength << ML_BITS);
|
|
|
-
|
|
|
- /* Copy Literals */
|
|
|
- LZ4_wildCopy8(op, anchor, op + litLength);
|
|
|
- op += litLength;
|
|
|
- DEBUGLOG(6, "seq.start:%i, literals=%u, match.start:%i",
|
|
|
- (int)(anchor - (const BYTE *)source), litLength, (int)(ip - (const BYTE *)source));
|
|
|
- }
|
|
|
-
|
|
|
- _next_match:
|
|
|
- /* at this stage, the following variables must be correctly set :
|
|
|
- * - ip : at start of LZ operation
|
|
|
- * - match : at start of previous pattern occurence; can be within current prefix, or within extDict
|
|
|
- * - offset : if maybe_ext_memSegment==1 (constant)
|
|
|
- * - lowLimit : must be == dictionary to mean "match is within extDict"; must be == source otherwise
|
|
|
- * - token and *token : position to write 4-bits for match length; higher 4-bits for literal length supposed already written
|
|
|
- */
|
|
|
-
|
|
|
- if ((outputDirective == fillOutput) &&
|
|
|
- (op + 2 /* offset */ + 1 /* token */ + MFLIMIT - MINMATCH /* min last literals so last match is <= end - MFLIMIT */ > olimit))
|
|
|
- {
|
|
|
- /* the match was too close to the end, rewind and go to last literals */
|
|
|
- op = token;
|
|
|
- goto _last_literals;
|
|
|
- }
|
|
|
-
|
|
|
- /* Encode Offset */
|
|
|
- if (maybe_extMem)
|
|
|
- { /* static test */
|
|
|
- DEBUGLOG(6, " with offset=%u (ext if > %i)", offset, (int)(ip - (const BYTE *)source));
|
|
|
- assert(offset <= LZ4_DISTANCE_MAX && offset > 0);
|
|
|
- LZ4_writeLE16(op, (U16)offset);
|
|
|
- op += 2;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- DEBUGLOG(6, " with offset=%u (same segment)", (U32)(ip - match));
|
|
|
- assert(ip - match <= LZ4_DISTANCE_MAX);
|
|
|
- LZ4_writeLE16(op, (U16)(ip - match));
|
|
|
- op += 2;
|
|
|
- }
|
|
|
-
|
|
|
- /* Encode MatchLength */
|
|
|
- {
|
|
|
- unsigned matchCode;
|
|
|
-
|
|
|
- if ((dictDirective == usingExtDict || dictDirective == usingDictCtx) && (lowLimit == dictionary) /* match within extDict */)
|
|
|
- {
|
|
|
- const BYTE *limit = ip + (dictEnd - match);
|
|
|
- assert(dictEnd > match);
|
|
|
- if (limit > matchlimit)
|
|
|
- limit = matchlimit;
|
|
|
- matchCode = LZ4_count(ip + MINMATCH, match + MINMATCH, limit);
|
|
|
- ip += (size_t)matchCode + MINMATCH;
|
|
|
- if (ip == limit)
|
|
|
- {
|
|
|
- unsigned const more = LZ4_count(limit, (const BYTE *)source, matchlimit);
|
|
|
- matchCode += more;
|
|
|
- ip += more;
|
|
|
- }
|
|
|
- DEBUGLOG(6, " with matchLength=%u starting in extDict", matchCode + MINMATCH);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- matchCode = LZ4_count(ip + MINMATCH, match + MINMATCH, matchlimit);
|
|
|
- ip += (size_t)matchCode + MINMATCH;
|
|
|
- DEBUGLOG(6, " with matchLength=%u", matchCode + MINMATCH);
|
|
|
- }
|
|
|
-
|
|
|
- if ((outputDirective) && /* Check output buffer overflow */
|
|
|
- (unlikely(op + (1 + LASTLITERALS) + (matchCode + 240) / 255 > olimit)))
|
|
|
- {
|
|
|
- if (outputDirective == fillOutput)
|
|
|
- {
|
|
|
- /* Match description too long : reduce it */
|
|
|
- U32 newMatchCode = 15 /* in token */ - 1 /* to avoid needing a zero byte */ + ((U32)(olimit - op) - 1 - LASTLITERALS) * 255;
|
|
|
- ip -= matchCode - newMatchCode;
|
|
|
- assert(newMatchCode < matchCode);
|
|
|
- matchCode = newMatchCode;
|
|
|
- if (unlikely(ip <= filledIp))
|
|
|
- {
|
|
|
- /* We have already filled up to filledIp so if ip ends up less than filledIp
|
|
|
- * we have positions in the hash table beyond the current position. This is
|
|
|
- * a problem if we reuse the hash table. So we have to remove these positions
|
|
|
- * from the hash table.
|
|
|
- */
|
|
|
- const BYTE *ptr;
|
|
|
- DEBUGLOG(5, "Clearing %u positions", (U32)(filledIp - ip));
|
|
|
- for (ptr = ip; ptr <= filledIp; ++ptr)
|
|
|
- {
|
|
|
- U32 const h = LZ4_hashPosition(ptr, tableType);
|
|
|
- LZ4_clearHash(h, cctx->hashTable, tableType);
|
|
|
- }
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- assert(outputDirective == limitedOutput);
|
|
|
- return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */
|
|
|
- }
|
|
|
- }
|
|
|
- if (matchCode >= ML_MASK)
|
|
|
- {
|
|
|
- *token += ML_MASK;
|
|
|
- matchCode -= ML_MASK;
|
|
|
- LZ4_write32(op, 0xFFFFFFFF);
|
|
|
- while (matchCode >= 4 * 255)
|
|
|
- {
|
|
|
- op += 4;
|
|
|
- LZ4_write32(op, 0xFFFFFFFF);
|
|
|
- matchCode -= 4 * 255;
|
|
|
- }
|
|
|
- op += matchCode / 255;
|
|
|
- *op++ = (BYTE)(matchCode % 255);
|
|
|
- }
|
|
|
- else
|
|
|
- *token += (BYTE)(matchCode);
|
|
|
- }
|
|
|
- /* Ensure we have enough space for the last literals. */
|
|
|
- assert(!(outputDirective == fillOutput && op + 1 + LASTLITERALS > olimit));
|
|
|
-
|
|
|
- anchor = ip;
|
|
|
-
|
|
|
- /* Test end of chunk */
|
|
|
- if (ip >= mflimitPlusOne)
|
|
|
- break;
|
|
|
-
|
|
|
- /* Fill table */
|
|
|
- LZ4_putPosition(ip - 2, cctx->hashTable, tableType, base);
|
|
|
-
|
|
|
- /* Test next position */
|
|
|
- if (tableType == byPtr)
|
|
|
- {
|
|
|
-
|
|
|
- match = LZ4_getPosition(ip, cctx->hashTable, tableType, base);
|
|
|
- LZ4_putPosition(ip, cctx->hashTable, tableType, base);
|
|
|
- if ((match + LZ4_DISTANCE_MAX >= ip) && (LZ4_read32(match) == LZ4_read32(ip)))
|
|
|
- {
|
|
|
- token = op++;
|
|
|
- *token = 0;
|
|
|
- goto _next_match;
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- { /* byU32, byU16 */
|
|
|
-
|
|
|
- U32 const h = LZ4_hashPosition(ip, tableType);
|
|
|
- U32 const current = (U32)(ip - base);
|
|
|
- U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType);
|
|
|
- assert(matchIndex < current);
|
|
|
- if (dictDirective == usingDictCtx)
|
|
|
- {
|
|
|
- if (matchIndex < startIndex)
|
|
|
- {
|
|
|
- /* there was no match, try the dictionary */
|
|
|
- matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32);
|
|
|
- match = dictBase + matchIndex;
|
|
|
- lowLimit = dictionary; /* required for match length counter */
|
|
|
- matchIndex += dictDelta;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- match = base + matchIndex;
|
|
|
- lowLimit = (const BYTE *)source; /* required for match length counter */
|
|
|
- }
|
|
|
- }
|
|
|
- else if (dictDirective == usingExtDict)
|
|
|
- {
|
|
|
- if (matchIndex < startIndex)
|
|
|
- {
|
|
|
- match = dictBase + matchIndex;
|
|
|
- lowLimit = dictionary; /* required for match length counter */
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- match = base + matchIndex;
|
|
|
- lowLimit = (const BYTE *)source; /* required for match length counter */
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- { /* single memory segment */
|
|
|
- match = base + matchIndex;
|
|
|
- }
|
|
|
- LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType);
|
|
|
- assert(matchIndex < current);
|
|
|
- if (((dictIssue == dictSmall) ? (matchIndex >= prefixIdxLimit) : 1) && (((tableType == byU16) && (LZ4_DISTANCE_MAX == LZ4_DISTANCE_ABSOLUTE_MAX)) ? 1 : (matchIndex + LZ4_DISTANCE_MAX >= current)) && (LZ4_read32(match) == LZ4_read32(ip)))
|
|
|
- {
|
|
|
- token = op++;
|
|
|
- *token = 0;
|
|
|
- if (maybe_extMem)
|
|
|
- offset = current - matchIndex;
|
|
|
- DEBUGLOG(6, "seq.start:%i, literals=%u, match.start:%i",
|
|
|
- (int)(anchor - (const BYTE *)source), 0, (int)(ip - (const BYTE *)source));
|
|
|
- goto _next_match;
|
|
|
- }
|
|
|
- }
|
|
|
-
|
|
|
- /* Prepare next loop */
|
|
|
- forwardH = LZ4_hashPosition(++ip, tableType);
|
|
|
- }
|
|
|
-
|
|
|
-_last_literals:
|
|
|
- /* Encode Last Literals */
|
|
|
- {
|
|
|
- size_t lastRun = (size_t)(iend - anchor);
|
|
|
- if ((outputDirective) && /* Check output buffer overflow */
|
|
|
- (op + lastRun + 1 + ((lastRun + 255 - RUN_MASK) / 255) > olimit))
|
|
|
- {
|
|
|
- if (outputDirective == fillOutput)
|
|
|
- {
|
|
|
- /* adapt lastRun to fill 'dst' */
|
|
|
- assert(olimit >= op);
|
|
|
- lastRun = (size_t)(olimit - op) - 1 /*token*/;
|
|
|
- lastRun -= (lastRun + 256 - RUN_MASK) / 256; /*additional length tokens*/
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- assert(outputDirective == limitedOutput);
|
|
|
- return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */
|
|
|
- }
|
|
|
- }
|
|
|
- DEBUGLOG(6, "Final literal run : %i literals", (int)lastRun);
|
|
|
- if (lastRun >= RUN_MASK)
|
|
|
- {
|
|
|
- size_t accumulator = lastRun - RUN_MASK;
|
|
|
- *op++ = RUN_MASK << ML_BITS;
|
|
|
- for (; accumulator >= 255; accumulator -= 255)
|
|
|
- *op++ = 255;
|
|
|
- *op++ = (BYTE)accumulator;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- *op++ = (BYTE)(lastRun << ML_BITS);
|
|
|
- }
|
|
|
- LZ4_memcpy(op, anchor, lastRun);
|
|
|
- ip = anchor + lastRun;
|
|
|
- op += lastRun;
|
|
|
- }
|
|
|
-
|
|
|
- if (outputDirective == fillOutput)
|
|
|
- {
|
|
|
- *inputConsumed = (int)(((const char *)ip) - source);
|
|
|
- }
|
|
|
- result = (int)(((char *)op) - dest);
|
|
|
- assert(result > 0);
|
|
|
- DEBUGLOG(5, "LZ4_compress_generic: compressed %i bytes into %i bytes", inputSize, result);
|
|
|
- return result;
|
|
|
-}
|
|
|
-
|
|
|
-/** LZ4_compress_generic() :
|
|
|
- * inlined, to ensure branches are decided at compilation time;
|
|
|
- * takes care of src == (NULL, 0)
|
|
|
- * and forward the rest to LZ4_compress_generic_validated */
|
|
|
-LZ4_FORCE_INLINE int LZ4_compress_generic(
|
|
|
- LZ4_stream_t_internal *const cctx,
|
|
|
- const char *const src,
|
|
|
- char *const dst,
|
|
|
- const int srcSize,
|
|
|
- int *inputConsumed, /* only written when outputDirective == fillOutput */
|
|
|
- const int dstCapacity,
|
|
|
- const limitedOutput_directive outputDirective,
|
|
|
- const tableType_t tableType,
|
|
|
- const dict_directive dictDirective,
|
|
|
- const dictIssue_directive dictIssue,
|
|
|
- const int acceleration)
|
|
|
-{
|
|
|
- DEBUGLOG(5, "LZ4_compress_generic: srcSize=%i, dstCapacity=%i",
|
|
|
- srcSize, dstCapacity);
|
|
|
-
|
|
|
- if ((U32)srcSize > (U32)LZ4_MAX_INPUT_SIZE)
|
|
|
- {
|
|
|
- return 0;
|
|
|
- } /* Unsupported srcSize, too large (or negative) */
|
|
|
- if (srcSize == 0)
|
|
|
- { /* src == NULL supported if srcSize == 0 */
|
|
|
- if (outputDirective != notLimited && dstCapacity <= 0)
|
|
|
- return 0; /* no output, can't write anything */
|
|
|
- DEBUGLOG(5, "Generating an empty block");
|
|
|
- assert(outputDirective == notLimited || dstCapacity >= 1);
|
|
|
- assert(dst != NULL);
|
|
|
- dst[0] = 0;
|
|
|
- if (outputDirective == fillOutput)
|
|
|
- {
|
|
|
- assert(inputConsumed != NULL);
|
|
|
- *inputConsumed = 0;
|
|
|
- }
|
|
|
- return 1;
|
|
|
- }
|
|
|
- assert(src != NULL);
|
|
|
-
|
|
|
- return LZ4_compress_generic_validated(cctx, src, dst, srcSize,
|
|
|
- inputConsumed, /* only written into if outputDirective == fillOutput */
|
|
|
- dstCapacity, outputDirective,
|
|
|
- tableType, dictDirective, dictIssue, acceleration);
|
|
|
-}
|
|
|
-
|
|
|
-int LZ4_compress_fast_extState(void *state, const char *source, char *dest, int inputSize, int maxOutputSize, int acceleration)
|
|
|
-{
|
|
|
- LZ4_stream_t_internal *const ctx = &LZ4_initStream(state, sizeof(LZ4_stream_t))->internal_donotuse;
|
|
|
- assert(ctx != NULL);
|
|
|
- if (acceleration < 1)
|
|
|
- acceleration = LZ4_ACCELERATION_DEFAULT;
|
|
|
- if (acceleration > LZ4_ACCELERATION_MAX)
|
|
|
- acceleration = LZ4_ACCELERATION_MAX;
|
|
|
- if (maxOutputSize >= LZ4_compressBound(inputSize))
|
|
|
- {
|
|
|
- if (inputSize < LZ4_64Klimit)
|
|
|
- {
|
|
|
- return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, byU16, noDict, noDictIssue, acceleration);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- const tableType_t tableType = ((sizeof(void *) == 4) && ((uptrval)source > LZ4_DISTANCE_MAX)) ? byPtr : byU32;
|
|
|
- return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- if (inputSize < LZ4_64Klimit)
|
|
|
- {
|
|
|
- return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- const tableType_t tableType = ((sizeof(void *) == 4) && ((uptrval)source > LZ4_DISTANCE_MAX)) ? byPtr : byU32;
|
|
|
- return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, noDict, noDictIssue, acceleration);
|
|
|
- }
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-/**
|
|
|
- * LZ4_compress_fast_extState_fastReset() :
|
|
|
- * A variant of LZ4_compress_fast_extState().
|
|
|
- *
|
|
|
- * Using this variant avoids an expensive initialization step. It is only safe
|
|
|
- * to call if the state buffer is known to be correctly initialized already
|
|
|
- * (see comment in lz4.h on LZ4_resetStream_fast() for a definition of
|
|
|
- * "correctly initialized").
|
|
|
- */
|
|
|
-int LZ4_compress_fast_extState_fastReset(void *state, const char *src, char *dst, int srcSize, int dstCapacity, int acceleration)
|
|
|
-{
|
|
|
- LZ4_stream_t_internal *ctx = &((LZ4_stream_t *)state)->internal_donotuse;
|
|
|
- if (acceleration < 1)
|
|
|
- acceleration = LZ4_ACCELERATION_DEFAULT;
|
|
|
- if (acceleration > LZ4_ACCELERATION_MAX)
|
|
|
- acceleration = LZ4_ACCELERATION_MAX;
|
|
|
-
|
|
|
- if (dstCapacity >= LZ4_compressBound(srcSize))
|
|
|
- {
|
|
|
- if (srcSize < LZ4_64Klimit)
|
|
|
- {
|
|
|
- const tableType_t tableType = byU16;
|
|
|
- LZ4_prepareTable(ctx, srcSize, tableType);
|
|
|
- if (ctx->currentOffset)
|
|
|
- {
|
|
|
- return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, dictSmall, acceleration);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- const tableType_t tableType = ((sizeof(void *) == 4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32;
|
|
|
- LZ4_prepareTable(ctx, srcSize, tableType);
|
|
|
- return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- if (srcSize < LZ4_64Klimit)
|
|
|
- {
|
|
|
- const tableType_t tableType = byU16;
|
|
|
- LZ4_prepareTable(ctx, srcSize, tableType);
|
|
|
- if (ctx->currentOffset)
|
|
|
- {
|
|
|
- return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, dictSmall, acceleration);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration);
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- const tableType_t tableType = ((sizeof(void *) == 4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32;
|
|
|
- LZ4_prepareTable(ctx, srcSize, tableType);
|
|
|
- return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration);
|
|
|
- }
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-int LZ4_compress_fast(const char *source, char *dest, int inputSize, int maxOutputSize, int acceleration)
|
|
|
-{
|
|
|
- int result;
|
|
|
-#if (LZ4_HEAPMODE)
|
|
|
- LZ4_stream_t *ctxPtr = ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
|
|
|
- if (ctxPtr == NULL)
|
|
|
- return 0;
|
|
|
-#else
|
|
|
- LZ4_stream_t ctx;
|
|
|
- LZ4_stream_t *const ctxPtr = &ctx;
|
|
|
-#endif
|
|
|
- result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration);
|
|
|
-
|
|
|
-#if (LZ4_HEAPMODE)
|
|
|
- FREEMEM(ctxPtr);
|
|
|
-#endif
|
|
|
- return result;
|
|
|
-}
|
|
|
-
|
|
|
-int LZ4_compress_default(const char *src, char *dst, int srcSize, int maxOutputSize)
|
|
|
-{
|
|
|
- return LZ4_compress_fast(src, dst, srcSize, maxOutputSize, 1);
|
|
|
-}
|
|
|
-
|
|
|
-/* Note!: This function leaves the stream in an unclean/broken state!
|
|
|
- * It is not safe to subsequently use the same state with a _fastReset() or
|
|
|
- * _continue() call without resetting it. */
|
|
|
-static int LZ4_compress_destSize_extState(LZ4_stream_t *state, const char *src, char *dst, int *srcSizePtr, int targetDstSize)
|
|
|
-{
|
|
|
- void *const s = LZ4_initStream(state, sizeof(*state));
|
|
|
- assert(s != NULL);
|
|
|
- (void)s;
|
|
|
-
|
|
|
- if (targetDstSize >= LZ4_compressBound(*srcSizePtr))
|
|
|
- { /* compression success is guaranteed */
|
|
|
- return LZ4_compress_fast_extState(state, src, dst, *srcSizePtr, targetDstSize, 1);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- if (*srcSizePtr < LZ4_64Klimit)
|
|
|
- {
|
|
|
- return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, byU16, noDict, noDictIssue, 1);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- tableType_t const addrMode = ((sizeof(void *) == 4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32;
|
|
|
- return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, addrMode, noDict, noDictIssue, 1);
|
|
|
- }
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-int LZ4_compress_destSize(const char *src, char *dst, int *srcSizePtr, int targetDstSize)
|
|
|
-{
|
|
|
-#if (LZ4_HEAPMODE)
|
|
|
- LZ4_stream_t *ctx = (LZ4_stream_t *)ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
|
|
|
- if (ctx == NULL)
|
|
|
- return 0;
|
|
|
-#else
|
|
|
- LZ4_stream_t ctxBody;
|
|
|
- LZ4_stream_t *ctx = &ctxBody;
|
|
|
-#endif
|
|
|
-
|
|
|
- int result = LZ4_compress_destSize_extState(ctx, src, dst, srcSizePtr, targetDstSize);
|
|
|
-
|
|
|
-#if (LZ4_HEAPMODE)
|
|
|
- FREEMEM(ctx);
|
|
|
-#endif
|
|
|
- return result;
|
|
|
-}
|
|
|
-
|
|
|
-/*-******************************
|
|
|
- * Streaming functions
|
|
|
- ********************************/
|
|
|
-
|
|
|
-LZ4_stream_t *LZ4_createStream(void)
|
|
|
-{
|
|
|
- LZ4_stream_t *const lz4s = (LZ4_stream_t *)ALLOC(sizeof(LZ4_stream_t));
|
|
|
- LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /* A compilation error here means LZ4_STREAMSIZE is not large enough */
|
|
|
- DEBUGLOG(4, "LZ4_createStream %p", lz4s);
|
|
|
- if (lz4s == NULL)
|
|
|
- return NULL;
|
|
|
- LZ4_initStream(lz4s, sizeof(*lz4s));
|
|
|
- return lz4s;
|
|
|
-}
|
|
|
-
|
|
|
-static size_t LZ4_stream_t_alignment(void)
|
|
|
-{
|
|
|
-#if LZ4_ALIGN_TEST
|
|
|
- typedef struct
|
|
|
- {
|
|
|
- char c;
|
|
|
- LZ4_stream_t t;
|
|
|
- } t_a;
|
|
|
- return sizeof(t_a) - sizeof(LZ4_stream_t);
|
|
|
-#else
|
|
|
- return 1; /* effectively disabled */
|
|
|
-#endif
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_stream_t *LZ4_initStream(void *buffer, size_t size)
|
|
|
-{
|
|
|
- DEBUGLOG(5, "LZ4_initStream");
|
|
|
- if (buffer == NULL)
|
|
|
- {
|
|
|
- return NULL;
|
|
|
- }
|
|
|
- if (size < sizeof(LZ4_stream_t))
|
|
|
- {
|
|
|
- return NULL;
|
|
|
- }
|
|
|
- if (!LZ4_isAligned(buffer, LZ4_stream_t_alignment()))
|
|
|
- return NULL;
|
|
|
- MEM_INIT(buffer, 0, sizeof(LZ4_stream_t_internal));
|
|
|
- return (LZ4_stream_t *)buffer;
|
|
|
-}
|
|
|
-
|
|
|
-/* resetStream is now deprecated,
|
|
|
- * prefer initStream() which is more general */
|
|
|
-void LZ4_resetStream(LZ4_stream_t *LZ4_stream)
|
|
|
-{
|
|
|
- DEBUGLOG(5, "LZ4_resetStream (ctx:%p)", LZ4_stream);
|
|
|
- MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t_internal));
|
|
|
-}
|
|
|
-
|
|
|
-void LZ4_resetStream_fast(LZ4_stream_t *ctx)
|
|
|
-{
|
|
|
- LZ4_prepareTable(&(ctx->internal_donotuse), 0, byU32);
|
|
|
-}
|
|
|
-
|
|
|
-int LZ4_freeStream(LZ4_stream_t *LZ4_stream)
|
|
|
-{
|
|
|
- if (!LZ4_stream)
|
|
|
- return 0; /* support free on NULL */
|
|
|
- DEBUGLOG(5, "LZ4_freeStream %p", LZ4_stream);
|
|
|
- FREEMEM(LZ4_stream);
|
|
|
- return (0);
|
|
|
-}
|
|
|
-
|
|
|
-#define HASH_UNIT sizeof(reg_t)
|
|
|
-int LZ4_loadDict(LZ4_stream_t *LZ4_dict, const char *dictionary, int dictSize)
|
|
|
-{
|
|
|
- LZ4_stream_t_internal *dict = &LZ4_dict->internal_donotuse;
|
|
|
- const tableType_t tableType = byU32;
|
|
|
- const BYTE *p = (const BYTE *)dictionary;
|
|
|
- const BYTE *const dictEnd = p + dictSize;
|
|
|
- const BYTE *base;
|
|
|
-
|
|
|
- DEBUGLOG(4, "LZ4_loadDict (%i bytes from %p into %p)", dictSize, dictionary, LZ4_dict);
|
|
|
-
|
|
|
- /* It's necessary to reset the context,
|
|
|
- * and not just continue it with prepareTable()
|
|
|
- * to avoid any risk of generating overflowing matchIndex
|
|
|
- * when compressing using this dictionary */
|
|
|
- LZ4_resetStream(LZ4_dict);
|
|
|
-
|
|
|
- /* We always increment the offset by 64 KB, since, if the dict is longer,
|
|
|
- * we truncate it to the last 64k, and if it's shorter, we still want to
|
|
|
- * advance by a whole window length so we can provide the guarantee that
|
|
|
- * there are only valid offsets in the window, which allows an optimization
|
|
|
- * in LZ4_compress_fast_continue() where it uses noDictIssue even when the
|
|
|
- * dictionary isn't a full 64k. */
|
|
|
- dict->currentOffset += 64 KB;
|
|
|
-
|
|
|
- if (dictSize < (int)HASH_UNIT)
|
|
|
- {
|
|
|
- return 0;
|
|
|
- }
|
|
|
-
|
|
|
- if ((dictEnd - p) > 64 KB)
|
|
|
- p = dictEnd - 64 KB;
|
|
|
- base = dictEnd - dict->currentOffset;
|
|
|
- dict->dictionary = p;
|
|
|
- dict->dictSize = (U32)(dictEnd - p);
|
|
|
- dict->tableType = (U32)tableType;
|
|
|
-
|
|
|
- while (p <= dictEnd - HASH_UNIT)
|
|
|
- {
|
|
|
- LZ4_putPosition(p, dict->hashTable, tableType, base);
|
|
|
- p += 3;
|
|
|
- }
|
|
|
-
|
|
|
- return (int)dict->dictSize;
|
|
|
-}
|
|
|
-
|
|
|
-void LZ4_attach_dictionary(LZ4_stream_t *workingStream, const LZ4_stream_t *dictionaryStream)
|
|
|
-{
|
|
|
- const LZ4_stream_t_internal *dictCtx = dictionaryStream == NULL ? NULL : &(dictionaryStream->internal_donotuse);
|
|
|
-
|
|
|
- DEBUGLOG(4, "LZ4_attach_dictionary (%p, %p, size %u)",
|
|
|
- workingStream, dictionaryStream,
|
|
|
- dictCtx != NULL ? dictCtx->dictSize : 0);
|
|
|
-
|
|
|
- if (dictCtx != NULL)
|
|
|
- {
|
|
|
- /* If the current offset is zero, we will never look in the
|
|
|
- * external dictionary context, since there is no value a table
|
|
|
- * entry can take that indicate a miss. In that case, we need
|
|
|
- * to bump the offset to something non-zero.
|
|
|
- */
|
|
|
- if (workingStream->internal_donotuse.currentOffset == 0)
|
|
|
- {
|
|
|
- workingStream->internal_donotuse.currentOffset = 64 KB;
|
|
|
- }
|
|
|
-
|
|
|
- /* Don't actually attach an empty dictionary.
|
|
|
- */
|
|
|
- if (dictCtx->dictSize == 0)
|
|
|
- {
|
|
|
- dictCtx = NULL;
|
|
|
- }
|
|
|
- }
|
|
|
- workingStream->internal_donotuse.dictCtx = dictCtx;
|
|
|
-}
|
|
|
-
|
|
|
-static void LZ4_renormDictT(LZ4_stream_t_internal *LZ4_dict, int nextSize)
|
|
|
-{
|
|
|
- assert(nextSize >= 0);
|
|
|
- if (LZ4_dict->currentOffset + (unsigned)nextSize > 0x80000000)
|
|
|
- { /* potential ptrdiff_t overflow (32-bits mode) */
|
|
|
- /* rescale hash table */
|
|
|
- U32 const delta = LZ4_dict->currentOffset - 64 KB;
|
|
|
- const BYTE *dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize;
|
|
|
- int i;
|
|
|
- DEBUGLOG(4, "LZ4_renormDictT");
|
|
|
- for (i = 0; i < LZ4_HASH_SIZE_U32; i++)
|
|
|
- {
|
|
|
- if (LZ4_dict->hashTable[i] < delta)
|
|
|
- LZ4_dict->hashTable[i] = 0;
|
|
|
- else
|
|
|
- LZ4_dict->hashTable[i] -= delta;
|
|
|
- }
|
|
|
- LZ4_dict->currentOffset = 64 KB;
|
|
|
- if (LZ4_dict->dictSize > 64 KB)
|
|
|
- LZ4_dict->dictSize = 64 KB;
|
|
|
- LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize;
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-int LZ4_compress_fast_continue(LZ4_stream_t *LZ4_stream,
|
|
|
- const char *source, char *dest,
|
|
|
- int inputSize, int maxOutputSize,
|
|
|
- int acceleration)
|
|
|
-{
|
|
|
- const tableType_t tableType = byU32;
|
|
|
- LZ4_stream_t_internal *streamPtr = &LZ4_stream->internal_donotuse;
|
|
|
- const BYTE *dictEnd = streamPtr->dictionary + streamPtr->dictSize;
|
|
|
-
|
|
|
- DEBUGLOG(5, "LZ4_compress_fast_continue (inputSize=%i)", inputSize);
|
|
|
-
|
|
|
- LZ4_renormDictT(streamPtr, inputSize); /* avoid index overflow */
|
|
|
- if (acceleration < 1)
|
|
|
- acceleration = LZ4_ACCELERATION_DEFAULT;
|
|
|
- if (acceleration > LZ4_ACCELERATION_MAX)
|
|
|
- acceleration = LZ4_ACCELERATION_MAX;
|
|
|
-
|
|
|
- /* invalidate tiny dictionaries */
|
|
|
- if ((streamPtr->dictSize - 1 < 4 - 1) /* intentional underflow */
|
|
|
- && (dictEnd != (const BYTE *)source))
|
|
|
- {
|
|
|
- DEBUGLOG(5, "LZ4_compress_fast_continue: dictSize(%u) at addr:%p is too small", streamPtr->dictSize, streamPtr->dictionary);
|
|
|
- streamPtr->dictSize = 0;
|
|
|
- streamPtr->dictionary = (const BYTE *)source;
|
|
|
- dictEnd = (const BYTE *)source;
|
|
|
- }
|
|
|
-
|
|
|
- /* Check overlapping input/dictionary space */
|
|
|
- {
|
|
|
- const BYTE *sourceEnd = (const BYTE *)source + inputSize;
|
|
|
- if ((sourceEnd > streamPtr->dictionary) && (sourceEnd < dictEnd))
|
|
|
- {
|
|
|
- streamPtr->dictSize = (U32)(dictEnd - sourceEnd);
|
|
|
- if (streamPtr->dictSize > 64 KB)
|
|
|
- streamPtr->dictSize = 64 KB;
|
|
|
- if (streamPtr->dictSize < 4)
|
|
|
- streamPtr->dictSize = 0;
|
|
|
- streamPtr->dictionary = dictEnd - streamPtr->dictSize;
|
|
|
- }
|
|
|
- }
|
|
|
-
|
|
|
- /* prefix mode : source data follows dictionary */
|
|
|
- if (dictEnd == (const BYTE *)source)
|
|
|
- {
|
|
|
- if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
|
|
|
- return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, dictSmall, acceleration);
|
|
|
- else
|
|
|
- return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, noDictIssue, acceleration);
|
|
|
- }
|
|
|
-
|
|
|
- /* external dictionary mode */
|
|
|
- {
|
|
|
- int result;
|
|
|
- if (streamPtr->dictCtx)
|
|
|
- {
|
|
|
- /* We depend here on the fact that dictCtx'es (produced by
|
|
|
- * LZ4_loadDict) guarantee that their tables contain no references
|
|
|
- * to offsets between dictCtx->currentOffset - 64 KB and
|
|
|
- * dictCtx->currentOffset - dictCtx->dictSize. This makes it safe
|
|
|
- * to use noDictIssue even when the dict isn't a full 64 KB.
|
|
|
- */
|
|
|
- if (inputSize > 4 KB)
|
|
|
- {
|
|
|
- /* For compressing large blobs, it is faster to pay the setup
|
|
|
- * cost to copy the dictionary's tables into the active context,
|
|
|
- * so that the compression loop is only looking into one table.
|
|
|
- */
|
|
|
- LZ4_memcpy(streamPtr, streamPtr->dictCtx, sizeof(*streamPtr));
|
|
|
- result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingDictCtx, noDictIssue, acceleration);
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
|
|
|
- {
|
|
|
- result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, dictSmall, acceleration);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration);
|
|
|
- }
|
|
|
- }
|
|
|
- streamPtr->dictionary = (const BYTE *)source;
|
|
|
- streamPtr->dictSize = (U32)inputSize;
|
|
|
- return result;
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-/* Hidden debug function, to force-test external dictionary mode */
|
|
|
-int LZ4_compress_forceExtDict(LZ4_stream_t *LZ4_dict, const char *source, char *dest, int srcSize)
|
|
|
-{
|
|
|
- LZ4_stream_t_internal *streamPtr = &LZ4_dict->internal_donotuse;
|
|
|
- int result;
|
|
|
-
|
|
|
- LZ4_renormDictT(streamPtr, srcSize);
|
|
|
-
|
|
|
- if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
|
|
|
- {
|
|
|
- result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, dictSmall, 1);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, noDictIssue, 1);
|
|
|
- }
|
|
|
-
|
|
|
- streamPtr->dictionary = (const BYTE *)source;
|
|
|
- streamPtr->dictSize = (U32)srcSize;
|
|
|
-
|
|
|
- return result;
|
|
|
-}
|
|
|
-
|
|
|
-/*! LZ4_saveDict() :
|
|
|
- * If previously compressed data block is not guaranteed to remain available at its memory location,
|
|
|
- * save it into a safer place (char* safeBuffer).
|
|
|
- * Note : you don't need to call LZ4_loadDict() afterwards,
|
|
|
- * dictionary is immediately usable, you can therefore call LZ4_compress_fast_continue().
|
|
|
- * Return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error.
|
|
|
- */
|
|
|
-int LZ4_saveDict(LZ4_stream_t *LZ4_dict, char *safeBuffer, int dictSize)
|
|
|
-{
|
|
|
- LZ4_stream_t_internal *const dict = &LZ4_dict->internal_donotuse;
|
|
|
- const BYTE *const previousDictEnd = dict->dictionary + dict->dictSize;
|
|
|
-
|
|
|
- if ((U32)dictSize > 64 KB)
|
|
|
- {
|
|
|
- dictSize = 64 KB;
|
|
|
- } /* useless to define a dictionary > 64 KB */
|
|
|
- if ((U32)dictSize > dict->dictSize)
|
|
|
- {
|
|
|
- dictSize = (int)dict->dictSize;
|
|
|
- }
|
|
|
-
|
|
|
- if (safeBuffer == NULL)
|
|
|
- assert(dictSize == 0);
|
|
|
- if (dictSize > 0)
|
|
|
- memmove(safeBuffer, previousDictEnd - dictSize, dictSize);
|
|
|
-
|
|
|
- dict->dictionary = (const BYTE *)safeBuffer;
|
|
|
- dict->dictSize = (U32)dictSize;
|
|
|
-
|
|
|
- return dictSize;
|
|
|
-}
|
|
|
-
|
|
|
-/*-*******************************
|
|
|
- * Decompression functions
|
|
|
- ********************************/
|
|
|
-
|
|
|
-typedef enum
|
|
|
-{
|
|
|
- endOnOutputSize = 0,
|
|
|
- endOnInputSize = 1
|
|
|
-} endCondition_directive;
|
|
|
-typedef enum
|
|
|
-{
|
|
|
- decode_full_block = 0,
|
|
|
- partial_decode = 1
|
|
|
-} earlyEnd_directive;
|
|
|
-
|
|
|
-#undef MIN
|
|
|
-#define MIN(a, b) ((a) < (b) ? (a) : (b))
|
|
|
-
|
|
|
-/* Read the variable-length literal or match length.
|
|
|
- *
|
|
|
- * ip - pointer to use as input.
|
|
|
- * lencheck - end ip. Return an error if ip advances >= lencheck.
|
|
|
- * loop_check - check ip >= lencheck in body of loop. Returns loop_error if so.
|
|
|
- * initial_check - check ip >= lencheck before start of loop. Returns initial_error if so.
|
|
|
- * error (output) - error code. Should be set to 0 before call.
|
|
|
- */
|
|
|
-typedef enum
|
|
|
-{
|
|
|
- loop_error = -2,
|
|
|
- initial_error = -1,
|
|
|
- ok = 0
|
|
|
-} variable_length_error;
|
|
|
-LZ4_FORCE_INLINE unsigned
|
|
|
-read_variable_length(const BYTE **ip, const BYTE *lencheck,
|
|
|
- int loop_check, int initial_check,
|
|
|
- variable_length_error *error)
|
|
|
-{
|
|
|
- U32 length = 0;
|
|
|
- U32 s;
|
|
|
- if (initial_check && unlikely((*ip) >= lencheck))
|
|
|
- { /* overflow detection */
|
|
|
- *error = initial_error;
|
|
|
- return length;
|
|
|
- }
|
|
|
- do
|
|
|
- {
|
|
|
- s = **ip;
|
|
|
- (*ip)++;
|
|
|
- length += s;
|
|
|
- if (loop_check && unlikely((*ip) >= lencheck))
|
|
|
- { /* overflow detection */
|
|
|
- *error = loop_error;
|
|
|
- return length;
|
|
|
- }
|
|
|
- } while (s == 255);
|
|
|
-
|
|
|
- return length;
|
|
|
-}
|
|
|
-
|
|
|
-/*! LZ4_decompress_generic() :
|
|
|
- * This generic decompression function covers all use cases.
|
|
|
- * It shall be instantiated several times, using different sets of directives.
|
|
|
- * Note that it is important for performance that this function really get inlined,
|
|
|
- * in order to remove useless branches during compilation optimization.
|
|
|
- */
|
|
|
-LZ4_FORCE_INLINE int
|
|
|
-LZ4_decompress_generic(
|
|
|
- const char *const src,
|
|
|
- char *const dst,
|
|
|
- int srcSize,
|
|
|
- int outputSize, /* If endOnInput==endOnInputSize, this value is `dstCapacity` */
|
|
|
-
|
|
|
- endCondition_directive endOnInput, /* endOnOutputSize, endOnInputSize */
|
|
|
- earlyEnd_directive partialDecoding, /* full, partial */
|
|
|
- dict_directive dict, /* noDict, withPrefix64k, usingExtDict */
|
|
|
- const BYTE *const lowPrefix, /* always <= dst, == dst when no prefix */
|
|
|
- const BYTE *const dictStart, /* only if dict==usingExtDict */
|
|
|
- const size_t dictSize /* note : = 0 if noDict */
|
|
|
-)
|
|
|
-{
|
|
|
- if (src == NULL)
|
|
|
- {
|
|
|
- return -1;
|
|
|
- }
|
|
|
-
|
|
|
- {
|
|
|
- const BYTE *ip = (const BYTE *)src;
|
|
|
- const BYTE *const iend = ip + srcSize;
|
|
|
-
|
|
|
- BYTE *op = (BYTE *)dst;
|
|
|
- BYTE *const oend = op + outputSize;
|
|
|
- BYTE *cpy;
|
|
|
-
|
|
|
- const BYTE *const dictEnd = (dictStart == NULL) ? NULL : dictStart + dictSize;
|
|
|
-
|
|
|
- const int safeDecode = (endOnInput == endOnInputSize);
|
|
|
- const int checkOffset = ((safeDecode) && (dictSize < (int)(64 KB)));
|
|
|
-
|
|
|
- /* Set up the "end" pointers for the shortcut. */
|
|
|
- const BYTE *const shortiend = iend - (endOnInput ? 14 : 8) /*maxLL*/ - 2 /*offset*/;
|
|
|
- const BYTE *const shortoend = oend - (endOnInput ? 14 : 8) /*maxLL*/ - 18 /*maxML*/;
|
|
|
-
|
|
|
- const BYTE *match;
|
|
|
- size_t offset;
|
|
|
- unsigned token;
|
|
|
- size_t length;
|
|
|
-
|
|
|
- DEBUGLOG(5, "LZ4_decompress_generic (srcSize:%i, dstSize:%i)", srcSize, outputSize);
|
|
|
-
|
|
|
- /* Special cases */
|
|
|
- assert(lowPrefix <= op);
|
|
|
- if ((endOnInput) && (unlikely(outputSize == 0)))
|
|
|
- {
|
|
|
- /* Empty output buffer */
|
|
|
- if (partialDecoding)
|
|
|
- return 0;
|
|
|
- return ((srcSize == 1) && (*ip == 0)) ? 0 : -1;
|
|
|
- }
|
|
|
- if ((!endOnInput) && (unlikely(outputSize == 0)))
|
|
|
- {
|
|
|
- return (*ip == 0 ? 1 : -1);
|
|
|
- }
|
|
|
- if ((endOnInput) && unlikely(srcSize == 0))
|
|
|
- {
|
|
|
- return -1;
|
|
|
- }
|
|
|
-
|
|
|
- /* Currently the fast loop shows a regression on qualcomm arm chips. */
|
|
|
-#if LZ4_FAST_DEC_LOOP
|
|
|
- if ((oend - op) < FASTLOOP_SAFE_DISTANCE)
|
|
|
- {
|
|
|
- DEBUGLOG(6, "skip fast decode loop");
|
|
|
- goto safe_decode;
|
|
|
- }
|
|
|
-
|
|
|
- /* Fast loop : decode sequences as long as output < iend-FASTLOOP_SAFE_DISTANCE */
|
|
|
- while (1)
|
|
|
- {
|
|
|
- /* Main fastloop assertion: We can always wildcopy FASTLOOP_SAFE_DISTANCE */
|
|
|
- assert(oend - op >= FASTLOOP_SAFE_DISTANCE);
|
|
|
- if (endOnInput)
|
|
|
- {
|
|
|
- assert(ip < iend);
|
|
|
- }
|
|
|
- token = *ip++;
|
|
|
- length = token >> ML_BITS; /* literal length */
|
|
|
-
|
|
|
- assert(!endOnInput || ip <= iend); /* ip < iend before the increment */
|
|
|
-
|
|
|
- /* decode literal length */
|
|
|
- if (length == RUN_MASK)
|
|
|
- {
|
|
|
- variable_length_error error = ok;
|
|
|
- length += read_variable_length(&ip, iend - RUN_MASK, (int)endOnInput, (int)endOnInput, &error);
|
|
|
- if (error == initial_error)
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- }
|
|
|
- if ((safeDecode) && unlikely((uptrval)(op) + length < (uptrval)(op)))
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- } /* overflow detection */
|
|
|
- if ((safeDecode) && unlikely((uptrval)(ip) + length < (uptrval)(ip)))
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- } /* overflow detection */
|
|
|
-
|
|
|
- /* copy literals */
|
|
|
- cpy = op + length;
|
|
|
- LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH);
|
|
|
- if (endOnInput)
|
|
|
- { /* LZ4_decompress_safe() */
|
|
|
- if ((cpy > oend - 32) || (ip + length > iend - 32))
|
|
|
- {
|
|
|
- goto safe_literal_copy;
|
|
|
- }
|
|
|
- LZ4_wildCopy32(op, ip, cpy);
|
|
|
- }
|
|
|
- else
|
|
|
- { /* LZ4_decompress_fast() */
|
|
|
- if (cpy > oend - 8)
|
|
|
- {
|
|
|
- goto safe_literal_copy;
|
|
|
- }
|
|
|
- LZ4_wildCopy8(op, ip, cpy); /* LZ4_decompress_fast() cannot copy more than 8 bytes at a time :
|
|
|
- * it doesn't know input length, and only relies on end-of-block properties */
|
|
|
- }
|
|
|
- ip += length;
|
|
|
- op = cpy;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- cpy = op + length;
|
|
|
- if (endOnInput)
|
|
|
- { /* LZ4_decompress_safe() */
|
|
|
- DEBUGLOG(7, "copy %u bytes in a 16-bytes stripe", (unsigned)length);
|
|
|
- /* We don't need to check oend, since we check it once for each loop below */
|
|
|
- if (ip > iend - (16 + 1 /*max lit + offset + nextToken*/))
|
|
|
- {
|
|
|
- goto safe_literal_copy;
|
|
|
- }
|
|
|
- /* Literals can only be 14, but hope compilers optimize if we copy by a register size */
|
|
|
- LZ4_memcpy(op, ip, 16);
|
|
|
- }
|
|
|
- else
|
|
|
- { /* LZ4_decompress_fast() */
|
|
|
- /* LZ4_decompress_fast() cannot copy more than 8 bytes at a time :
|
|
|
- * it doesn't know input length, and relies on end-of-block properties */
|
|
|
- LZ4_memcpy(op, ip, 8);
|
|
|
- if (length > 8)
|
|
|
- {
|
|
|
- LZ4_memcpy(op + 8, ip + 8, 8);
|
|
|
- }
|
|
|
- }
|
|
|
- ip += length;
|
|
|
- op = cpy;
|
|
|
- }
|
|
|
-
|
|
|
- /* get offset */
|
|
|
- offset = LZ4_readLE16(ip);
|
|
|
- ip += 2;
|
|
|
- match = op - offset;
|
|
|
- assert(match <= op);
|
|
|
-
|
|
|
- /* get matchlength */
|
|
|
- length = token & ML_MASK;
|
|
|
-
|
|
|
- if (length == ML_MASK)
|
|
|
- {
|
|
|
- variable_length_error error = ok;
|
|
|
- if ((checkOffset) && (unlikely(match + dictSize < lowPrefix)))
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- } /* Error : offset outside buffers */
|
|
|
- length += read_variable_length(&ip, iend - LASTLITERALS + 1, (int)endOnInput, 0, &error);
|
|
|
- if (error != ok)
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- }
|
|
|
- if ((safeDecode) && unlikely((uptrval)(op) + length < (uptrval)op))
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- } /* overflow detection */
|
|
|
- length += MINMATCH;
|
|
|
- if (op + length >= oend - FASTLOOP_SAFE_DISTANCE)
|
|
|
- {
|
|
|
- goto safe_match_copy;
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- length += MINMATCH;
|
|
|
- if (op + length >= oend - FASTLOOP_SAFE_DISTANCE)
|
|
|
- {
|
|
|
- goto safe_match_copy;
|
|
|
- }
|
|
|
-
|
|
|
- /* Fastpath check: Avoids a branch in LZ4_wildCopy32 if true */
|
|
|
- if ((dict == withPrefix64k) || (match >= lowPrefix))
|
|
|
- {
|
|
|
- if (offset >= 8)
|
|
|
- {
|
|
|
- assert(match >= lowPrefix);
|
|
|
- assert(match <= op);
|
|
|
- assert(op + 18 <= oend);
|
|
|
-
|
|
|
- LZ4_memcpy(op, match, 8);
|
|
|
- LZ4_memcpy(op + 8, match + 8, 8);
|
|
|
- LZ4_memcpy(op + 16, match + 16, 2);
|
|
|
- op += length;
|
|
|
- continue;
|
|
|
- }
|
|
|
- }
|
|
|
- }
|
|
|
-
|
|
|
- if (checkOffset && (unlikely(match + dictSize < lowPrefix)))
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- } /* Error : offset outside buffers */
|
|
|
- /* match starting within external dictionary */
|
|
|
- if ((dict == usingExtDict) && (match < lowPrefix))
|
|
|
- {
|
|
|
- if (unlikely(op + length > oend - LASTLITERALS))
|
|
|
- {
|
|
|
- if (partialDecoding)
|
|
|
- {
|
|
|
- DEBUGLOG(7, "partialDecoding: dictionary match, close to dstEnd");
|
|
|
- length = MIN(length, (size_t)(oend - op));
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- goto _output_error; /* end-of-block condition violated */
|
|
|
- }
|
|
|
- }
|
|
|
-
|
|
|
- if (length <= (size_t)(lowPrefix - match))
|
|
|
- {
|
|
|
- /* match fits entirely within external dictionary : just copy */
|
|
|
- memmove(op, dictEnd - (lowPrefix - match), length);
|
|
|
- op += length;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- /* match stretches into both external dictionary and current block */
|
|
|
- size_t const copySize = (size_t)(lowPrefix - match);
|
|
|
- size_t const restSize = length - copySize;
|
|
|
- LZ4_memcpy(op, dictEnd - copySize, copySize);
|
|
|
- op += copySize;
|
|
|
- if (restSize > (size_t)(op - lowPrefix))
|
|
|
- { /* overlap copy */
|
|
|
- BYTE *const endOfMatch = op + restSize;
|
|
|
- const BYTE *copyFrom = lowPrefix;
|
|
|
- while (op < endOfMatch)
|
|
|
- {
|
|
|
- *op++ = *copyFrom++;
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- LZ4_memcpy(op, lowPrefix, restSize);
|
|
|
- op += restSize;
|
|
|
- }
|
|
|
- }
|
|
|
- continue;
|
|
|
- }
|
|
|
-
|
|
|
- /* copy match within block */
|
|
|
- cpy = op + length;
|
|
|
-
|
|
|
- assert((op <= oend) && (oend - op >= 32));
|
|
|
- if (unlikely(offset < 16))
|
|
|
- {
|
|
|
- LZ4_memcpy_using_offset(op, match, cpy, offset);
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- LZ4_wildCopy32(op, match, cpy);
|
|
|
- }
|
|
|
-
|
|
|
- op = cpy; /* wildcopy correction */
|
|
|
- }
|
|
|
- safe_decode:
|
|
|
-#endif
|
|
|
-
|
|
|
- /* Main Loop : decode remaining sequences where output < FASTLOOP_SAFE_DISTANCE */
|
|
|
- while (1)
|
|
|
- {
|
|
|
- token = *ip++;
|
|
|
- length = token >> ML_BITS; /* literal length */
|
|
|
-
|
|
|
- assert(!endOnInput || ip <= iend); /* ip < iend before the increment */
|
|
|
-
|
|
|
- /* A two-stage shortcut for the most common case:
|
|
|
- * 1) If the literal length is 0..14, and there is enough space,
|
|
|
- * enter the shortcut and copy 16 bytes on behalf of the literals
|
|
|
- * (in the fast mode, only 8 bytes can be safely copied this way).
|
|
|
- * 2) Further if the match length is 4..18, copy 18 bytes in a similar
|
|
|
- * manner; but we ensure that there's enough space in the output for
|
|
|
- * those 18 bytes earlier, upon entering the shortcut (in other words,
|
|
|
- * there is a combined check for both stages).
|
|
|
- */
|
|
|
- if ((endOnInput ? length != RUN_MASK : length <= 8)
|
|
|
- /* strictly "less than" on input, to re-enter the loop with at least one byte */
|
|
|
- && likely((endOnInput ? ip < shortiend : 1) & (op <= shortoend)))
|
|
|
- {
|
|
|
- /* Copy the literals */
|
|
|
- LZ4_memcpy(op, ip, endOnInput ? 16 : 8);
|
|
|
- op += length;
|
|
|
- ip += length;
|
|
|
-
|
|
|
- /* The second stage: prepare for match copying, decode full info.
|
|
|
- * If it doesn't work out, the info won't be wasted. */
|
|
|
- length = token & ML_MASK; /* match length */
|
|
|
- offset = LZ4_readLE16(ip);
|
|
|
- ip += 2;
|
|
|
- match = op - offset;
|
|
|
- assert(match <= op); /* check overflow */
|
|
|
-
|
|
|
- /* Do not deal with overlapping matches. */
|
|
|
- if ((length != ML_MASK) && (offset >= 8) && (dict == withPrefix64k || match >= lowPrefix))
|
|
|
- {
|
|
|
- /* Copy the match. */
|
|
|
- LZ4_memcpy(op + 0, match + 0, 8);
|
|
|
- LZ4_memcpy(op + 8, match + 8, 8);
|
|
|
- LZ4_memcpy(op + 16, match + 16, 2);
|
|
|
- op += length + MINMATCH;
|
|
|
- /* Both stages worked, load the next token. */
|
|
|
- continue;
|
|
|
- }
|
|
|
-
|
|
|
- /* The second stage didn't work out, but the info is ready.
|
|
|
- * Propel it right to the point of match copying. */
|
|
|
- goto _copy_match;
|
|
|
- }
|
|
|
-
|
|
|
- /* decode literal length */
|
|
|
- if (length == RUN_MASK)
|
|
|
- {
|
|
|
- variable_length_error error = ok;
|
|
|
- length += read_variable_length(&ip, iend - RUN_MASK, (int)endOnInput, (int)endOnInput, &error);
|
|
|
- if (error == initial_error)
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- }
|
|
|
- if ((safeDecode) && unlikely((uptrval)(op) + length < (uptrval)(op)))
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- } /* overflow detection */
|
|
|
- if ((safeDecode) && unlikely((uptrval)(ip) + length < (uptrval)(ip)))
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- } /* overflow detection */
|
|
|
- }
|
|
|
-
|
|
|
- /* copy literals */
|
|
|
- cpy = op + length;
|
|
|
-#if LZ4_FAST_DEC_LOOP
|
|
|
- safe_literal_copy:
|
|
|
-#endif
|
|
|
- LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH);
|
|
|
- if (((endOnInput) && ((cpy > oend - MFLIMIT) || (ip + length > iend - (2 + 1 + LASTLITERALS)))) || ((!endOnInput) && (cpy > oend - WILDCOPYLENGTH)))
|
|
|
- {
|
|
|
- /* We've either hit the input parsing restriction or the output parsing restriction.
|
|
|
- * In the normal scenario, decoding a full block, it must be the last sequence,
|
|
|
- * otherwise it's an error (invalid input or dimensions).
|
|
|
- * In partialDecoding scenario, it's necessary to ensure there is no buffer overflow.
|
|
|
- */
|
|
|
- if (partialDecoding)
|
|
|
- {
|
|
|
- /* Since we are partial decoding we may be in this block because of the output parsing
|
|
|
- * restriction, which is not valid since the output buffer is allowed to be undersized.
|
|
|
- */
|
|
|
- assert(endOnInput);
|
|
|
- DEBUGLOG(7, "partialDecoding: copying literals, close to input or output end")
|
|
|
- DEBUGLOG(7, "partialDecoding: literal length = %u", (unsigned)length);
|
|
|
- DEBUGLOG(7, "partialDecoding: remaining space in dstBuffer : %i", (int)(oend - op));
|
|
|
- DEBUGLOG(7, "partialDecoding: remaining space in srcBuffer : %i", (int)(iend - ip));
|
|
|
- /* Finishing in the middle of a literals segment,
|
|
|
- * due to lack of input.
|
|
|
- */
|
|
|
- if (ip + length > iend)
|
|
|
- {
|
|
|
- length = (size_t)(iend - ip);
|
|
|
- cpy = op + length;
|
|
|
- }
|
|
|
- /* Finishing in the middle of a literals segment,
|
|
|
- * due to lack of output space.
|
|
|
- */
|
|
|
- if (cpy > oend)
|
|
|
- {
|
|
|
- cpy = oend;
|
|
|
- assert(op <= oend);
|
|
|
- length = (size_t)(oend - op);
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- /* We must be on the last sequence because of the parsing limitations so check
|
|
|
- * that we exactly regenerate the original size (must be exact when !endOnInput).
|
|
|
- */
|
|
|
- if ((!endOnInput) && (cpy != oend))
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- }
|
|
|
- /* We must be on the last sequence (or invalid) because of the parsing limitations
|
|
|
- * so check that we exactly consume the input and don't overrun the output buffer.
|
|
|
- */
|
|
|
- if ((endOnInput) && ((ip + length != iend) || (cpy > oend)))
|
|
|
- {
|
|
|
- DEBUGLOG(6, "should have been last run of literals")
|
|
|
- DEBUGLOG(6, "ip(%p) + length(%i) = %p != iend (%p)", ip, (int)length, ip + length, iend);
|
|
|
- DEBUGLOG(6, "or cpy(%p) > oend(%p)", cpy, oend);
|
|
|
- goto _output_error;
|
|
|
- }
|
|
|
- }
|
|
|
- memmove(op, ip, length); /* supports overlapping memory regions; only matters for in-place decompression scenarios */
|
|
|
- ip += length;
|
|
|
- op += length;
|
|
|
- /* Necessarily EOF when !partialDecoding.
|
|
|
- * When partialDecoding, it is EOF if we've either
|
|
|
- * filled the output buffer or
|
|
|
- * can't proceed with reading an offset for following match.
|
|
|
- */
|
|
|
- if (!partialDecoding || (cpy == oend) || (ip >= (iend - 2)))
|
|
|
- {
|
|
|
- break;
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- LZ4_wildCopy8(op, ip, cpy); /* may overwrite up to WILDCOPYLENGTH beyond cpy */
|
|
|
- ip += length;
|
|
|
- op = cpy;
|
|
|
- }
|
|
|
-
|
|
|
- /* get offset */
|
|
|
- offset = LZ4_readLE16(ip);
|
|
|
- ip += 2;
|
|
|
- match = op - offset;
|
|
|
-
|
|
|
- /* get matchlength */
|
|
|
- length = token & ML_MASK;
|
|
|
-
|
|
|
- _copy_match:
|
|
|
- if (length == ML_MASK)
|
|
|
- {
|
|
|
- variable_length_error error = ok;
|
|
|
- length += read_variable_length(&ip, iend - LASTLITERALS + 1, (int)endOnInput, 0, &error);
|
|
|
- if (error != ok)
|
|
|
- goto _output_error;
|
|
|
- if ((safeDecode) && unlikely((uptrval)(op) + length < (uptrval)op))
|
|
|
- goto _output_error; /* overflow detection */
|
|
|
- }
|
|
|
- length += MINMATCH;
|
|
|
-
|
|
|
-#if LZ4_FAST_DEC_LOOP
|
|
|
- safe_match_copy:
|
|
|
-#endif
|
|
|
- if ((checkOffset) && (unlikely(match + dictSize < lowPrefix)))
|
|
|
- goto _output_error; /* Error : offset outside buffers */
|
|
|
- /* match starting within external dictionary */
|
|
|
- if ((dict == usingExtDict) && (match < lowPrefix))
|
|
|
- {
|
|
|
- if (unlikely(op + length > oend - LASTLITERALS))
|
|
|
- {
|
|
|
- if (partialDecoding)
|
|
|
- length = MIN(length, (size_t)(oend - op));
|
|
|
- else
|
|
|
- goto _output_error; /* doesn't respect parsing restriction */
|
|
|
- }
|
|
|
-
|
|
|
- if (length <= (size_t)(lowPrefix - match))
|
|
|
- {
|
|
|
- /* match fits entirely within external dictionary : just copy */
|
|
|
- memmove(op, dictEnd - (lowPrefix - match), length);
|
|
|
- op += length;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- /* match stretches into both external dictionary and current block */
|
|
|
- size_t const copySize = (size_t)(lowPrefix - match);
|
|
|
- size_t const restSize = length - copySize;
|
|
|
- LZ4_memcpy(op, dictEnd - copySize, copySize);
|
|
|
- op += copySize;
|
|
|
- if (restSize > (size_t)(op - lowPrefix))
|
|
|
- { /* overlap copy */
|
|
|
- BYTE *const endOfMatch = op + restSize;
|
|
|
- const BYTE *copyFrom = lowPrefix;
|
|
|
- while (op < endOfMatch)
|
|
|
- *op++ = *copyFrom++;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- LZ4_memcpy(op, lowPrefix, restSize);
|
|
|
- op += restSize;
|
|
|
- }
|
|
|
- }
|
|
|
- continue;
|
|
|
- }
|
|
|
- assert(match >= lowPrefix);
|
|
|
-
|
|
|
- /* copy match within block */
|
|
|
- cpy = op + length;
|
|
|
-
|
|
|
- /* partialDecoding : may end anywhere within the block */
|
|
|
- assert(op <= oend);
|
|
|
- if (partialDecoding && (cpy > oend - MATCH_SAFEGUARD_DISTANCE))
|
|
|
- {
|
|
|
- size_t const mlen = MIN(length, (size_t)(oend - op));
|
|
|
- const BYTE *const matchEnd = match + mlen;
|
|
|
- BYTE *const copyEnd = op + mlen;
|
|
|
- if (matchEnd > op)
|
|
|
- { /* overlap copy */
|
|
|
- while (op < copyEnd)
|
|
|
- {
|
|
|
- *op++ = *match++;
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- LZ4_memcpy(op, match, mlen);
|
|
|
- }
|
|
|
- op = copyEnd;
|
|
|
- if (op == oend)
|
|
|
- {
|
|
|
- break;
|
|
|
- }
|
|
|
- continue;
|
|
|
- }
|
|
|
-
|
|
|
- if (unlikely(offset < 8))
|
|
|
- {
|
|
|
- LZ4_write32(op, 0); /* silence msan warning when offset==0 */
|
|
|
- op[0] = match[0];
|
|
|
- op[1] = match[1];
|
|
|
- op[2] = match[2];
|
|
|
- op[3] = match[3];
|
|
|
- match += inc32table[offset];
|
|
|
- LZ4_memcpy(op + 4, match, 4);
|
|
|
- match -= dec64table[offset];
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- LZ4_memcpy(op, match, 8);
|
|
|
- match += 8;
|
|
|
- }
|
|
|
- op += 8;
|
|
|
-
|
|
|
- if (unlikely(cpy > oend - MATCH_SAFEGUARD_DISTANCE))
|
|
|
- {
|
|
|
- BYTE *const oCopyLimit = oend - (WILDCOPYLENGTH - 1);
|
|
|
- if (cpy > oend - LASTLITERALS)
|
|
|
- {
|
|
|
- goto _output_error;
|
|
|
- } /* Error : last LASTLITERALS bytes must be literals (uncompressed) */
|
|
|
- if (op < oCopyLimit)
|
|
|
- {
|
|
|
- LZ4_wildCopy8(op, match, oCopyLimit);
|
|
|
- match += oCopyLimit - op;
|
|
|
- op = oCopyLimit;
|
|
|
- }
|
|
|
- while (op < cpy)
|
|
|
- {
|
|
|
- *op++ = *match++;
|
|
|
- }
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- LZ4_memcpy(op, match, 8);
|
|
|
- if (length > 16)
|
|
|
- {
|
|
|
- LZ4_wildCopy8(op + 8, match + 8, cpy);
|
|
|
- }
|
|
|
- }
|
|
|
- op = cpy; /* wildcopy correction */
|
|
|
- }
|
|
|
-
|
|
|
- /* end of decoding */
|
|
|
- if (endOnInput)
|
|
|
- {
|
|
|
- DEBUGLOG(5, "decoded %i bytes", (int)(((char *)op) - dst));
|
|
|
- return (int)(((char *)op) - dst); /* Nb of output bytes decoded */
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- return (int)(((const char *)ip) - src); /* Nb of input bytes read */
|
|
|
- }
|
|
|
-
|
|
|
- /* Overflow error detected */
|
|
|
- _output_error:
|
|
|
- return (int)(-(((const char *)ip) - src)) - 1;
|
|
|
- }
|
|
|
-}
|
|
|
-
|
|
|
-/*===== Instantiate the API decoding functions. =====*/
|
|
|
-
|
|
|
-LZ4_FORCE_O2
|
|
|
-int LZ4_decompress_safe(const char *source, char *dest, int compressedSize, int maxDecompressedSize)
|
|
|
-{
|
|
|
- return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize,
|
|
|
- endOnInputSize, decode_full_block, noDict,
|
|
|
- (BYTE *)dest, NULL, 0);
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_O2
|
|
|
-int LZ4_decompress_safe_partial(const char *src, char *dst, int compressedSize, int targetOutputSize, int dstCapacity)
|
|
|
-{
|
|
|
- dstCapacity = MIN(targetOutputSize, dstCapacity);
|
|
|
- return LZ4_decompress_generic(src, dst, compressedSize, dstCapacity,
|
|
|
- endOnInputSize, partial_decode,
|
|
|
- noDict, (BYTE *)dst, NULL, 0);
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_O2
|
|
|
-int LZ4_decompress_fast(const char *source, char *dest, int originalSize)
|
|
|
-{
|
|
|
- return LZ4_decompress_generic(source, dest, 0, originalSize,
|
|
|
- endOnOutputSize, decode_full_block, withPrefix64k,
|
|
|
- (BYTE *)dest - 64 KB, NULL, 0);
|
|
|
-}
|
|
|
-
|
|
|
-/*===== Instantiate a few more decoding cases, used more than once. =====*/
|
|
|
-
|
|
|
-LZ4_FORCE_O2 /* Exported, an obsolete API function. */
|
|
|
- int
|
|
|
- LZ4_decompress_safe_withPrefix64k(const char *source, char *dest, int compressedSize, int maxOutputSize)
|
|
|
-{
|
|
|
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
|
|
|
- endOnInputSize, decode_full_block, withPrefix64k,
|
|
|
- (BYTE *)dest - 64 KB, NULL, 0);
|
|
|
-}
|
|
|
-
|
|
|
-/* Another obsolete API function, paired with the previous one. */
|
|
|
-int LZ4_decompress_fast_withPrefix64k(const char *source, char *dest, int originalSize)
|
|
|
-{
|
|
|
- /* LZ4_decompress_fast doesn't validate match offsets,
|
|
|
- * and thus serves well with any prefixed dictionary. */
|
|
|
- return LZ4_decompress_fast(source, dest, originalSize);
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_O2
|
|
|
-static int LZ4_decompress_safe_withSmallPrefix(const char *source, char *dest, int compressedSize, int maxOutputSize,
|
|
|
- size_t prefixSize)
|
|
|
-{
|
|
|
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
|
|
|
- endOnInputSize, decode_full_block, noDict,
|
|
|
- (BYTE *)dest - prefixSize, NULL, 0);
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_O2
|
|
|
-int LZ4_decompress_safe_forceExtDict(const char *source, char *dest,
|
|
|
- int compressedSize, int maxOutputSize,
|
|
|
- const void *dictStart, size_t dictSize)
|
|
|
-{
|
|
|
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
|
|
|
- endOnInputSize, decode_full_block, usingExtDict,
|
|
|
- (BYTE *)dest, (const BYTE *)dictStart, dictSize);
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_O2
|
|
|
-static int LZ4_decompress_fast_extDict(const char *source, char *dest, int originalSize,
|
|
|
- const void *dictStart, size_t dictSize)
|
|
|
-{
|
|
|
- return LZ4_decompress_generic(source, dest, 0, originalSize,
|
|
|
- endOnOutputSize, decode_full_block, usingExtDict,
|
|
|
- (BYTE *)dest, (const BYTE *)dictStart, dictSize);
|
|
|
-}
|
|
|
-
|
|
|
-/* The "double dictionary" mode, for use with e.g. ring buffers: the first part
|
|
|
- * of the dictionary is passed as prefix, and the second via dictStart + dictSize.
|
|
|
- * These routines are used only once, in LZ4_decompress_*_continue().
|
|
|
- */
|
|
|
-LZ4_FORCE_INLINE
|
|
|
-int LZ4_decompress_safe_doubleDict(const char *source, char *dest, int compressedSize, int maxOutputSize,
|
|
|
- size_t prefixSize, const void *dictStart, size_t dictSize)
|
|
|
-{
|
|
|
- return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
|
|
|
- endOnInputSize, decode_full_block, usingExtDict,
|
|
|
- (BYTE *)dest - prefixSize, (const BYTE *)dictStart, dictSize);
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_INLINE
|
|
|
-int LZ4_decompress_fast_doubleDict(const char *source, char *dest, int originalSize,
|
|
|
- size_t prefixSize, const void *dictStart, size_t dictSize)
|
|
|
-{
|
|
|
- return LZ4_decompress_generic(source, dest, 0, originalSize,
|
|
|
- endOnOutputSize, decode_full_block, usingExtDict,
|
|
|
- (BYTE *)dest - prefixSize, (const BYTE *)dictStart, dictSize);
|
|
|
-}
|
|
|
-
|
|
|
-/*===== streaming decompression functions =====*/
|
|
|
-
|
|
|
-LZ4_streamDecode_t *LZ4_createStreamDecode(void)
|
|
|
-{
|
|
|
- LZ4_streamDecode_t *lz4s = (LZ4_streamDecode_t *)ALLOC_AND_ZERO(sizeof(LZ4_streamDecode_t));
|
|
|
- LZ4_STATIC_ASSERT(LZ4_STREAMDECODESIZE >= sizeof(LZ4_streamDecode_t_internal)); /* A compilation error here means LZ4_STREAMDECODESIZE is not large enough */
|
|
|
- return lz4s;
|
|
|
-}
|
|
|
-
|
|
|
-int LZ4_freeStreamDecode(LZ4_streamDecode_t *LZ4_stream)
|
|
|
-{
|
|
|
- if (LZ4_stream == NULL)
|
|
|
- {
|
|
|
- return 0;
|
|
|
- } /* support free on NULL */
|
|
|
- FREEMEM(LZ4_stream);
|
|
|
- return 0;
|
|
|
-}
|
|
|
-
|
|
|
-/*! LZ4_setStreamDecode() :
|
|
|
- * Use this function to instruct where to find the dictionary.
|
|
|
- * This function is not necessary if previous data is still available where it was decoded.
|
|
|
- * Loading a size of 0 is allowed (same effect as no dictionary).
|
|
|
- * @return : 1 if OK, 0 if error
|
|
|
- */
|
|
|
-int LZ4_setStreamDecode(LZ4_streamDecode_t *LZ4_streamDecode, const char *dictionary, int dictSize)
|
|
|
-{
|
|
|
- LZ4_streamDecode_t_internal *lz4sd = &LZ4_streamDecode->internal_donotuse;
|
|
|
- lz4sd->prefixSize = (size_t)dictSize;
|
|
|
- lz4sd->prefixEnd = (const BYTE *)dictionary + dictSize;
|
|
|
- lz4sd->externalDict = NULL;
|
|
|
- lz4sd->extDictSize = 0;
|
|
|
- return 1;
|
|
|
-}
|
|
|
-
|
|
|
-/*! LZ4_decoderRingBufferSize() :
|
|
|
- * when setting a ring buffer for streaming decompression (optional scenario),
|
|
|
- * provides the minimum size of this ring buffer
|
|
|
- * to be compatible with any source respecting maxBlockSize condition.
|
|
|
- * Note : in a ring buffer scenario,
|
|
|
- * blocks are presumed decompressed next to each other.
|
|
|
- * When not enough space remains for next block (remainingSize < maxBlockSize),
|
|
|
- * decoding resumes from beginning of ring buffer.
|
|
|
- * @return : minimum ring buffer size,
|
|
|
- * or 0 if there is an error (invalid maxBlockSize).
|
|
|
- */
|
|
|
-int LZ4_decoderRingBufferSize(int maxBlockSize)
|
|
|
-{
|
|
|
- if (maxBlockSize < 0)
|
|
|
- return 0;
|
|
|
- if (maxBlockSize > LZ4_MAX_INPUT_SIZE)
|
|
|
- return 0;
|
|
|
- if (maxBlockSize < 16)
|
|
|
- maxBlockSize = 16;
|
|
|
- return LZ4_DECODER_RING_BUFFER_SIZE(maxBlockSize);
|
|
|
-}
|
|
|
-
|
|
|
-/*
|
|
|
-*_continue() :
|
|
|
- These decoding functions allow decompression of multiple blocks in "streaming" mode.
|
|
|
- Previously decoded blocks must still be available at the memory position where they were decoded.
|
|
|
- If it's not possible, save the relevant part of decoded data into a safe buffer,
|
|
|
- and indicate where it stands using LZ4_setStreamDecode()
|
|
|
-*/
|
|
|
-LZ4_FORCE_O2
|
|
|
-int LZ4_decompress_safe_continue(LZ4_streamDecode_t *LZ4_streamDecode, const char *source, char *dest, int compressedSize, int maxOutputSize)
|
|
|
-{
|
|
|
- LZ4_streamDecode_t_internal *lz4sd = &LZ4_streamDecode->internal_donotuse;
|
|
|
- int result;
|
|
|
-
|
|
|
- if (lz4sd->prefixSize == 0)
|
|
|
- {
|
|
|
- /* The first call, no dictionary yet. */
|
|
|
- assert(lz4sd->extDictSize == 0);
|
|
|
- result = LZ4_decompress_safe(source, dest, compressedSize, maxOutputSize);
|
|
|
- if (result <= 0)
|
|
|
- return result;
|
|
|
- lz4sd->prefixSize = (size_t)result;
|
|
|
- lz4sd->prefixEnd = (BYTE *)dest + result;
|
|
|
- }
|
|
|
- else if (lz4sd->prefixEnd == (BYTE *)dest)
|
|
|
- {
|
|
|
- /* They're rolling the current segment. */
|
|
|
- if (lz4sd->prefixSize >= 64 KB - 1)
|
|
|
- result = LZ4_decompress_safe_withPrefix64k(source, dest, compressedSize, maxOutputSize);
|
|
|
- else if (lz4sd->extDictSize == 0)
|
|
|
- result = LZ4_decompress_safe_withSmallPrefix(source, dest, compressedSize, maxOutputSize,
|
|
|
- lz4sd->prefixSize);
|
|
|
- else
|
|
|
- result = LZ4_decompress_safe_doubleDict(source, dest, compressedSize, maxOutputSize,
|
|
|
- lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize);
|
|
|
- if (result <= 0)
|
|
|
- return result;
|
|
|
- lz4sd->prefixSize += (size_t)result;
|
|
|
- lz4sd->prefixEnd += result;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- /* The buffer wraps around, or they're switching to another buffer. */
|
|
|
- lz4sd->extDictSize = lz4sd->prefixSize;
|
|
|
- lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
|
|
|
- result = LZ4_decompress_safe_forceExtDict(source, dest, compressedSize, maxOutputSize,
|
|
|
- lz4sd->externalDict, lz4sd->extDictSize);
|
|
|
- if (result <= 0)
|
|
|
- return result;
|
|
|
- lz4sd->prefixSize = (size_t)result;
|
|
|
- lz4sd->prefixEnd = (BYTE *)dest + result;
|
|
|
- }
|
|
|
-
|
|
|
- return result;
|
|
|
-}
|
|
|
-
|
|
|
-LZ4_FORCE_O2
|
|
|
-int LZ4_decompress_fast_continue(LZ4_streamDecode_t *LZ4_streamDecode, const char *source, char *dest, int originalSize)
|
|
|
-{
|
|
|
- LZ4_streamDecode_t_internal *lz4sd = &LZ4_streamDecode->internal_donotuse;
|
|
|
- int result;
|
|
|
- assert(originalSize >= 0);
|
|
|
-
|
|
|
- if (lz4sd->prefixSize == 0)
|
|
|
- {
|
|
|
- assert(lz4sd->extDictSize == 0);
|
|
|
- result = LZ4_decompress_fast(source, dest, originalSize);
|
|
|
- if (result <= 0)
|
|
|
- return result;
|
|
|
- lz4sd->prefixSize = (size_t)originalSize;
|
|
|
- lz4sd->prefixEnd = (BYTE *)dest + originalSize;
|
|
|
- }
|
|
|
- else if (lz4sd->prefixEnd == (BYTE *)dest)
|
|
|
- {
|
|
|
- if (lz4sd->prefixSize >= 64 KB - 1 || lz4sd->extDictSize == 0)
|
|
|
- result = LZ4_decompress_fast(source, dest, originalSize);
|
|
|
- else
|
|
|
- result = LZ4_decompress_fast_doubleDict(source, dest, originalSize,
|
|
|
- lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize);
|
|
|
- if (result <= 0)
|
|
|
- return result;
|
|
|
- lz4sd->prefixSize += (size_t)originalSize;
|
|
|
- lz4sd->prefixEnd += originalSize;
|
|
|
- }
|
|
|
- else
|
|
|
- {
|
|
|
- lz4sd->extDictSize = lz4sd->prefixSize;
|
|
|
- lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
|
|
|
- result = LZ4_decompress_fast_extDict(source, dest, originalSize,
|
|
|
- lz4sd->externalDict, lz4sd->extDictSize);
|
|
|
- if (result <= 0)
|
|
|
- return result;
|
|
|
- lz4sd->prefixSize = (size_t)originalSize;
|
|
|
- lz4sd->prefixEnd = (BYTE *)dest + originalSize;
|
|
|
- }
|
|
|
-
|
|
|
- return result;
|
|
|
-}
|
|
|
-
|
|
|
-/*
|
|
|
-Advanced decoding functions :
|
|
|
-*_usingDict() :
|
|
|
- These decoding functions work the same as "_continue" ones,
|
|
|
- the dictionary must be explicitly provided within parameters
|
|
|
-*/
|
|
|
-
|
|
|
-int LZ4_decompress_safe_usingDict(const char *source, char *dest, int compressedSize, int maxOutputSize, const char *dictStart, int dictSize)
|
|
|
-{
|
|
|
- if (dictSize == 0)
|
|
|
- return LZ4_decompress_safe(source, dest, compressedSize, maxOutputSize);
|
|
|
- if (dictStart + dictSize == dest)
|
|
|
- {
|
|
|
- if (dictSize >= 64 KB - 1)
|
|
|
- {
|
|
|
- return LZ4_decompress_safe_withPrefix64k(source, dest, compressedSize, maxOutputSize);
|
|
|
- }
|
|
|
- assert(dictSize >= 0);
|
|
|
- return LZ4_decompress_safe_withSmallPrefix(source, dest, compressedSize, maxOutputSize, (size_t)dictSize);
|
|
|
- }
|
|
|
- assert(dictSize >= 0);
|
|
|
- return LZ4_decompress_safe_forceExtDict(source, dest, compressedSize, maxOutputSize, dictStart, (size_t)dictSize);
|
|
|
-}
|
|
|
-
|
|
|
-int LZ4_decompress_fast_usingDict(const char *source, char *dest, int originalSize, const char *dictStart, int dictSize)
|
|
|
-{
|
|
|
- if (dictSize == 0 || dictStart + dictSize == dest)
|
|
|
- return LZ4_decompress_fast(source, dest, originalSize);
|
|
|
- assert(dictSize >= 0);
|
|
|
- return LZ4_decompress_fast_extDict(source, dest, originalSize, dictStart, (size_t)dictSize);
|
|
|
-}
|
|
|
-
|
|
|
-/*=*************************************************
|
|
|
- * Obsolete Functions
|
|
|
- ***************************************************/
|
|
|
-/* obsolete compression functions */
|
|
|
-int LZ4_compress_limitedOutput(const char *source, char *dest, int inputSize, int maxOutputSize)
|
|
|
-{
|
|
|
- return LZ4_compress_default(source, dest, inputSize, maxOutputSize);
|
|
|
-}
|
|
|
-int LZ4_compress(const char *src, char *dest, int srcSize)
|
|
|
-{
|
|
|
- return LZ4_compress_default(src, dest, srcSize, LZ4_compressBound(srcSize));
|
|
|
-}
|
|
|
-int LZ4_compress_limitedOutput_withState(void *state, const char *src, char *dst, int srcSize, int dstSize)
|
|
|
-{
|
|
|
- return LZ4_compress_fast_extState(state, src, dst, srcSize, dstSize, 1);
|
|
|
-}
|
|
|
-int LZ4_compress_withState(void *state, const char *src, char *dst, int srcSize)
|
|
|
-{
|
|
|
- return LZ4_compress_fast_extState(state, src, dst, srcSize, LZ4_compressBound(srcSize), 1);
|
|
|
-}
|
|
|
-int LZ4_compress_limitedOutput_continue(LZ4_stream_t *LZ4_stream, const char *src, char *dst, int srcSize, int dstCapacity)
|
|
|
-{
|
|
|
- return LZ4_compress_fast_continue(LZ4_stream, src, dst, srcSize, dstCapacity, 1);
|
|
|
-}
|
|
|
-int LZ4_compress_continue(LZ4_stream_t *LZ4_stream, const char *source, char *dest, int inputSize)
|
|
|
-{
|
|
|
- return LZ4_compress_fast_continue(LZ4_stream, source, dest, inputSize, LZ4_compressBound(inputSize), 1);
|
|
|
-}
|
|
|
-
|
|
|
-/*
|
|
|
-These decompression functions are deprecated and should no longer be used.
|
|
|
-They are only provided here for compatibility with older user programs.
|
|
|
-- LZ4_uncompress is totally equivalent to LZ4_decompress_fast
|
|
|
-- LZ4_uncompress_unknownOutputSize is totally equivalent to LZ4_decompress_safe
|
|
|
-*/
|
|
|
-int LZ4_uncompress(const char *source, char *dest, int outputSize)
|
|
|
-{
|
|
|
- return LZ4_decompress_fast(source, dest, outputSize);
|
|
|
-}
|
|
|
-int LZ4_uncompress_unknownOutputSize(const char *source, char *dest, int isize, int maxOutputSize)
|
|
|
-{
|
|
|
- return LZ4_decompress_safe(source, dest, isize, maxOutputSize);
|
|
|
-}
|
|
|
-
|
|
|
-/* Obsolete Streaming functions */
|
|
|
-
|
|
|
-int LZ4_sizeofStreamState(void) { return LZ4_STREAMSIZE; }
|
|
|
-
|
|
|
-int LZ4_resetStreamState(void *state, char *inputBuffer)
|
|
|
-{
|
|
|
- (void)inputBuffer;
|
|
|
- LZ4_resetStream((LZ4_stream_t *)state);
|
|
|
- return 0;
|
|
|
-}
|
|
|
-
|
|
|
-void *LZ4_create(char *inputBuffer)
|
|
|
-{
|
|
|
- (void)inputBuffer;
|
|
|
- return LZ4_createStream();
|
|
|
-}
|
|
|
-
|
|
|
-char *LZ4_slideInputBuffer(void *state)
|
|
|
-{
|
|
|
- /* avoid const char * -> char * conversion warning */
|
|
|
- return (char *)(uptrval)((LZ4_stream_t *)state)->internal_donotuse.dictionary;
|
|
|
-}
|
|
|
-
|
|
|
-#endif /* LZ4_COMMONDEFS_ONLY */
|
|
|
-
|
|
|
-#else
|
|
|
-
|
|
|
-#endif
|
