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@@ -0,0 +1,1969 @@
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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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+/*-************************************
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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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+#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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+ * 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 ACCELERATION_DEFAULT 1
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+
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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__) \
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+ || 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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+# define LZ4_FORCE_SW_BITCOUNT
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+#endif
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+
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+
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+
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+/*-************************************
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+* Dependency
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+**************************************/
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+#define LZ4_STATIC_LINKING_ONLY
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+#define LZ4_DISABLE_DEPRECATE_WARNINGS /* due to LZ4_decompress_safe_withPrefix64k */
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+#include "lz4.h"
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+/* see also "memory routines" below */
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+
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+
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+/*-************************************
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+* Compiler Options
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+**************************************/
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+#ifdef _MSC_VER /* Visual Studio */
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+# include <intrin.h>
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+# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
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+# pragma warning(disable : 4293) /* disable: C4293: too large shift (32-bits) */
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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_GCC_PPC64LE and LZ4_FORCE_O2_INLINE_GCC_PPC64LE
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+ * Gcc on ppc64le generates an unrolled SIMDized loop for LZ4_wildCopy,
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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_wildCopy
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+ * functions are annotated with __attribute__((optimize("O2"))),
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+ * and also LZ4_wildCopy is forcibly inlined, so that the O2 attribute
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+ * of LZ4_wildCopy does not affect the compression speed.
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+ */
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+#if defined(__PPC64__) && defined(__LITTLE_ENDIAN__) && defined(__GNUC__)
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+# define LZ4_FORCE_O2_GCC_PPC64LE __attribute__((optimize("O2")))
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+# define LZ4_FORCE_O2_INLINE_GCC_PPC64LE __attribute__((optimize("O2"))) LZ4_FORCE_INLINE
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+#else
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+# define LZ4_FORCE_O2_GCC_PPC64LE
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+# define LZ4_FORCE_O2_INLINE_GCC_PPC64LE static
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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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+
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+/*-************************************
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+* Memory routines
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+**************************************/
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+#include <stdlib.h> /* malloc, calloc, free */
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+#define ALLOC(s) malloc(s)
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+#define ALLOC_AND_ZERO(s) calloc(1,s)
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+#define FREEMEM(p) free(p)
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+#include <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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+/*-************************************
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+* Basic Types
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+**************************************/
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+#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
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+# include <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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+ 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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+/*-************************************
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+* Reading and writing into memory
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+**************************************/
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+static unsigned LZ4_isLittleEndian(void)
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+{
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+ const union { U32 u; BYTE c[4]; } 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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+
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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 { U16 u16; U32 u32; reg_t uArch; } __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 through memcpy() */
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+
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+static U16 LZ4_read16(const void* memPtr)
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+{
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+ U16 val; memcpy(&val, memPtr, sizeof(val)); return val;
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+}
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+
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+static U32 LZ4_read32(const void* memPtr)
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+{
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+ U32 val; memcpy(&val, memPtr, sizeof(val)); return val;
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+}
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+
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+static reg_t LZ4_read_ARCH(const void* memPtr)
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+{
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+ reg_t val; memcpy(&val, memPtr, sizeof(val)); return val;
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+}
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+
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+static void LZ4_write16(void* memPtr, U16 value)
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+{
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+ memcpy(memPtr, &value, sizeof(value));
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+}
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+
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+static void LZ4_write32(void* memPtr, U32 value)
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+{
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+ memcpy(memPtr, &value, sizeof(value));
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+}
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+
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+#endif /* LZ4_FORCE_MEMORY_ACCESS */
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+
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+
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+static U16 LZ4_readLE16(const void* memPtr)
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+{
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+ if (LZ4_isLittleEndian()) {
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+ return LZ4_read16(memPtr);
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+ } else {
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+ const BYTE* p = (const BYTE*)memPtr;
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+ return (U16)((U16)p[0] + (p[1]<<8));
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+ }
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+}
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+
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+static void LZ4_writeLE16(void* memPtr, U16 value)
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+{
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+ if (LZ4_isLittleEndian()) {
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+ LZ4_write16(memPtr, value);
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+ } else {
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+ BYTE* p = (BYTE*)memPtr;
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+ p[0] = (BYTE) value;
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+ p[1] = (BYTE)(value>>8);
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+ }
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+}
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+
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+/* customized variant of memcpy, which can overwrite up to 8 bytes beyond dstEnd */
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+LZ4_FORCE_O2_INLINE_GCC_PPC64LE
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+void LZ4_wildCopy(void* dstPtr, const void* srcPtr, void* dstEnd)
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+{
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+ BYTE* d = (BYTE*)dstPtr;
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+ const BYTE* s = (const BYTE*)srcPtr;
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+ BYTE* const e = (BYTE*)dstEnd;
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+
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+ do { memcpy(d,s,8); d+=8; s+=8; } while (d<e);
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+}
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+
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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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+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 MAXD_LOG 16
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+#define MAX_DISTANCE ((1 << MAXD_LOG) - 1)
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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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+/*-************************************
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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) { enum { LZ4_static_assert = 1/(int)(!!(c)) }; } /* 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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+ if ((g_debuglog_enable) && (l<=LZ4_DEBUG)) { \
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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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+#else
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+# define DEBUGLOG(l, ...) {} /* disabled */
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+#endif
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+
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+
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+/*-************************************
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+* Common functions
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+**************************************/
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+static unsigned LZ4_NbCommonBytes (reg_t val)
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+{
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+ if (LZ4_isLittleEndian()) {
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+ if (sizeof(val)==8) {
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+# if defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT)
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+ unsigned long r = 0;
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+ _BitScanForward64( &r, (U64)val );
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+ return (int)(r>>3);
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+# elif (defined(__clang__) || (defined(__GNUC__) && (__GNUC__>=3))) && !defined(LZ4_FORCE_SW_BITCOUNT)
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+ return (__builtin_ctzll((U64)val) >> 3);
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+# else
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+ static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2,
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+ 0, 3, 1, 3, 1, 4, 2, 7,
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+ 0, 2, 3, 6, 1, 5, 3, 5,
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+ 1, 3, 4, 4, 2, 5, 6, 7,
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+ 7, 0, 1, 2, 3, 3, 4, 6,
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+ 2, 6, 5, 5, 3, 4, 5, 6,
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+ 7, 1, 2, 4, 6, 4, 4, 5,
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+ 7, 2, 6, 5, 7, 6, 7, 7 };
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|
|
+ return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58];
|
|
|
+# endif
|
|
|
+ } else /* 32 bits */ {
|
|
|
+# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
+ unsigned long r;
|
|
|
+ _BitScanForward( &r, (U32)val );
|
|
|
+ return (int)(r>>3);
|
|
|
+# elif (defined(__clang__) || (defined(__GNUC__) && (__GNUC__>=3))) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
+ return (__builtin_ctz((U32)val) >> 3);
|
|
|
+# else
|
|
|
+ static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0,
|
|
|
+ 3, 2, 2, 1, 3, 2, 0, 1,
|
|
|
+ 3, 3, 1, 2, 2, 2, 2, 0,
|
|
|
+ 3, 1, 2, 0, 1, 0, 1, 1 };
|
|
|
+ return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27];
|
|
|
+# endif
|
|
|
+ }
|
|
|
+ } else /* Big Endian CPU */ {
|
|
|
+ if (sizeof(val)==8) { /* 64-bits */
|
|
|
+# if defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
+ unsigned long r = 0;
|
|
|
+ _BitScanReverse64( &r, val );
|
|
|
+ return (unsigned)(r>>3);
|
|
|
+# elif (defined(__clang__) || (defined(__GNUC__) && (__GNUC__>=3))) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
+ return (__builtin_clzll((U64)val) >> 3);
|
|
|
+# else
|
|
|
+ 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
|
|
|
+ } else /* 32 bits */ {
|
|
|
+# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
+ unsigned long r = 0;
|
|
|
+ _BitScanReverse( &r, (unsigned long)val );
|
|
|
+ return (unsigned)(r>>3);
|
|
|
+# elif (defined(__clang__) || (defined(__GNUC__) && (__GNUC__>=3))) && !defined(LZ4_FORCE_SW_BITCOUNT)
|
|
|
+ return (__builtin_clz((U32)val) >> 3);
|
|
|
+# else
|
|
|
+ unsigned r;
|
|
|
+ if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }
|
|
|
+ r += (!val);
|
|
|
+ return r;
|
|
|
+# 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 { notLimited = 0, limitedOutput = 1, fillOutput = 2 } limitedOutput_directive;
|
|
|
+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() { return LZ4_STREAMSIZE; }
|
|
|
+
|
|
|
+
|
|
|
+/*-************************************
|
|
|
+* Internal Definitions used in Tests
|
|
|
+**************************************/
|
|
|
+#if defined (__cplusplus)
|
|
|
+extern "C" {
|
|
|
+#endif
|
|
|
+
|
|
|
+int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize);
|
|
|
+
|
|
|
+int LZ4_decompress_safe_forceExtDict(const char* in, char* out, int inSize, int outSize, const void* dict, size_t dictSize);
|
|
|
+
|
|
|
+#if defined (__cplusplus)
|
|
|
+}
|
|
|
+#endif
|
|
|
+
|
|
|
+/*-******************************
|
|
|
+* Compression functions
|
|
|
+********************************/
|
|
|
+static 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));
|
|
|
+}
|
|
|
+
|
|
|
+static U32 LZ4_hash5(U64 sequence, tableType_t const tableType)
|
|
|
+{
|
|
|
+ static const U64 prime5bytes = 889523592379ULL;
|
|
|
+ static const U64 prime8bytes = 11400714785074694791ULL;
|
|
|
+ const U32 hashLog = (tableType == byU16) ? LZ4_HASHLOG+1 : LZ4_HASHLOG;
|
|
|
+ if (LZ4_isLittleEndian())
|
|
|
+ return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog));
|
|
|
+ else
|
|
|
+ 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);
|
|
|
+}
|
|
|
+
|
|
|
+static 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; }
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+static 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)
|
|
|
+ */
|
|
|
+static 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 (cctx->tableType != clearedTable) {
|
|
|
+ if (cctx->tableType != tableType
|
|
|
+ || (tableType == byU16 && cctx->currentOffset + 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 = clearedTable;
|
|
|
+ } else {
|
|
|
+ DEBUGLOG(4, "LZ4_prepareTable: Re-use hash table (no reset)");
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Adding a gap, so all previous entries are > MAX_DISTANCE 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 */
|
|
|
+LZ4_FORCE_INLINE int LZ4_compress_generic(
|
|
|
+ LZ4_stream_t_internal* const cctx,
|
|
|
+ const char* const source,
|
|
|
+ char* const dest,
|
|
|
+ const int inputSize,
|
|
|
+ int *inputConsumed, /* only written when outputLimited == fillOutput */
|
|
|
+ const int maxOutputSize,
|
|
|
+ const limitedOutput_directive outputLimited,
|
|
|
+ const tableType_t tableType,
|
|
|
+ const dict_directive dictDirective,
|
|
|
+ const dictIssue_directive dictIssue,
|
|
|
+ const U32 acceleration)
|
|
|
+{
|
|
|
+ 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 + dictSize;
|
|
|
+ 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 = (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: srcSize=%i, tableType=%u", inputSize, tableType);
|
|
|
+ /* Init conditions */
|
|
|
+ if (outputLimited == fillOutput && maxOutputSize < 1) return 0; /* Impossible to store anything */
|
|
|
+ if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported inputSize, too large (or negative) */
|
|
|
+ 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 = (U16)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;
|
|
|
+
|
|
|
+ /* Find a match */
|
|
|
+ if (tableType == byPtr) {
|
|
|
+ const BYTE* forwardIp = ip;
|
|
|
+ unsigned step = 1;
|
|
|
+ unsigned 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+MAX_DISTANCE < ip)
|
|
|
+ || (LZ4_read32(match) != LZ4_read32(ip)) );
|
|
|
+
|
|
|
+ } else { /* byU32, byU16 */
|
|
|
+
|
|
|
+ const BYTE* forwardIp = ip;
|
|
|
+ unsigned step = 1;
|
|
|
+ unsigned 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);
|
|
|
+
|
|
|
+ if ((dictIssue == dictSmall) && (matchIndex < prefixIdxLimit)) continue; /* match outside of valid area */
|
|
|
+ assert(matchIndex < current);
|
|
|
+ if ((tableType != byU16) && (matchIndex+MAX_DISTANCE < current)) continue; /* too far */
|
|
|
+ if (tableType == byU16) assert((current - matchIndex) <= MAX_DISTANCE); /* too_far presumed impossible with byU16 */
|
|
|
+
|
|
|
+ if (LZ4_read32(match) == LZ4_read32(ip)) {
|
|
|
+ if (maybe_extMem) offset = current - matchIndex;
|
|
|
+ break; /* match found */
|
|
|
+ }
|
|
|
+
|
|
|
+ } while(1);
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Catch up */
|
|
|
+ while (((ip>anchor) & (match > lowLimit)) && (unlikely(ip[-1]==match[-1]))) { ip--; match--; }
|
|
|
+
|
|
|
+ /* Encode Literals */
|
|
|
+ { unsigned const litLength = (unsigned)(ip - anchor);
|
|
|
+ token = op++;
|
|
|
+ if ((outputLimited == limitedOutput) && /* Check output buffer overflow */
|
|
|
+ (unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength/255) > olimit)))
|
|
|
+ return 0;
|
|
|
+ if ((outputLimited == 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_wildCopy(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 ((outputLimited == 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 <= MAX_DISTANCE && offset > 0);
|
|
|
+ LZ4_writeLE16(op, (U16)offset); op+=2;
|
|
|
+ } else {
|
|
|
+ DEBUGLOG(6, " with offset=%u (same segment)", (U32)(ip - match));
|
|
|
+ assert(ip-match <= MAX_DISTANCE);
|
|
|
+ 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 += MINMATCH + matchCode;
|
|
|
+ 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 += MINMATCH + matchCode;
|
|
|
+ DEBUGLOG(6, " with matchLength=%u", matchCode+MINMATCH);
|
|
|
+ }
|
|
|
+
|
|
|
+ if ((outputLimited) && /* Check output buffer overflow */
|
|
|
+ (unlikely(op + (1 + LASTLITERALS) + (matchCode>>8) > olimit)) ) {
|
|
|
+ if (outputLimited == limitedOutput)
|
|
|
+ return 0;
|
|
|
+ if (outputLimited == fillOutput) {
|
|
|
+ /* Match description too long : reduce it */
|
|
|
+ U32 newMatchCode = 15 /* in token */ - 1 /* to avoid needing a zero byte */ + ((U32)(olimit - op) - 2 - 1 - LASTLITERALS) * 255;
|
|
|
+ ip -= matchCode - newMatchCode;
|
|
|
+ matchCode = newMatchCode;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ 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);
|
|
|
+ }
|
|
|
+
|
|
|
+ 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+MAX_DISTANCE >= 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) ? 1 : (matchIndex+MAX_DISTANCE >= 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 ( (outputLimited) && /* Check output buffer overflow */
|
|
|
+ (op + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > olimit)) {
|
|
|
+ if (outputLimited == fillOutput) {
|
|
|
+ /* adapt lastRun to fill 'dst' */
|
|
|
+ lastRun = (olimit-op) - 1;
|
|
|
+ lastRun -= (lastRun+240)/255;
|
|
|
+ }
|
|
|
+ if (outputLimited == limitedOutput)
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
+ 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);
|
|
|
+ }
|
|
|
+ memcpy(op, anchor, lastRun);
|
|
|
+ ip = anchor + lastRun;
|
|
|
+ op += lastRun;
|
|
|
+ }
|
|
|
+
|
|
|
+ if (outputLimited == fillOutput) {
|
|
|
+ *inputConsumed = (int) (((const char*)ip)-source);
|
|
|
+ }
|
|
|
+ DEBUGLOG(5, "LZ4_compress_generic: compressed %i bytes into %i bytes", inputSize, (int)(((char*)op) - dest));
|
|
|
+ return (int)(((char*)op) - dest);
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+int LZ4_compress_fast_extState(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
|
|
|
+{
|
|
|
+ LZ4_stream_t_internal* ctx = &((LZ4_stream_t*)state)->internal_donotuse;
|
|
|
+ if (acceleration < 1) acceleration = ACCELERATION_DEFAULT;
|
|
|
+ LZ4_resetStream((LZ4_stream_t*)state);
|
|
|
+ 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 > MAX_DISTANCE)) ? 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 > MAX_DISTANCE)) ? 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 = ACCELERATION_DEFAULT;
|
|
|
+
|
|
|
+ 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 > MAX_DISTANCE)) ? 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 > MAX_DISTANCE)) ? 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* source, char* dest, int inputSize, int maxOutputSize)
|
|
|
+{
|
|
|
+ return LZ4_compress_fast(source, dest, inputSize, maxOutputSize, 1);
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/* hidden debug function */
|
|
|
+/* strangely enough, gcc generates faster code when this function is uncommented, even if unused */
|
|
|
+int LZ4_compress_fast_force(const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration)
|
|
|
+{
|
|
|
+ LZ4_stream_t ctx;
|
|
|
+ LZ4_resetStream(&ctx);
|
|
|
+
|
|
|
+ if (inputSize < LZ4_64Klimit)
|
|
|
+ return LZ4_compress_generic(&ctx.internal_donotuse, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
|
|
|
+ else
|
|
|
+ return LZ4_compress_generic(&ctx.internal_donotuse, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, sizeof(void*)==8 ? byU32 : byPtr, noDict, noDictIssue, acceleration);
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/* 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)
|
|
|
+{
|
|
|
+ LZ4_resetStream(state);
|
|
|
+
|
|
|
+ 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 tableType = ((sizeof(void*)==4) && ((uptrval)src > MAX_DISTANCE)) ? byPtr : byU32;
|
|
|
+ return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, tableType, 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* 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_resetStream(lz4s);
|
|
|
+ return lz4s;
|
|
|
+}
|
|
|
+
|
|
|
+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));
|
|
|
+}
|
|
|
+
|
|
|
+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. */
|
|
|
+
|
|
|
+ if ((dictEnd - p) > 64 KB) p = dictEnd - 64 KB;
|
|
|
+ base = dictEnd - 64 KB - dict->currentOffset;
|
|
|
+ dict->dictionary = p;
|
|
|
+ dict->dictSize = (U32)(dictEnd - p);
|
|
|
+ dict->currentOffset += 64 KB;
|
|
|
+ dict->tableType = tableType;
|
|
|
+
|
|
|
+ if (dictSize < (int)HASH_UNIT) {
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
+
|
|
|
+ while (p <= dictEnd-HASH_UNIT) {
|
|
|
+ LZ4_putPosition(p, dict->hashTable, tableType, base);
|
|
|
+ p+=3;
|
|
|
+ }
|
|
|
+
|
|
|
+ return dict->dictSize;
|
|
|
+}
|
|
|
+
|
|
|
+void LZ4_attach_dictionary(LZ4_stream_t *working_stream, const LZ4_stream_t *dictionary_stream) {
|
|
|
+ if (dictionary_stream != 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 (working_stream->internal_donotuse.currentOffset == 0) {
|
|
|
+ working_stream->internal_donotuse.currentOffset = 64 KB;
|
|
|
+ }
|
|
|
+ working_stream->internal_donotuse.dictCtx = &(dictionary_stream->internal_donotuse);
|
|
|
+ } else {
|
|
|
+ working_stream->internal_donotuse.dictCtx = NULL;
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, int nextSize)
|
|
|
+{
|
|
|
+ if (LZ4_dict->currentOffset + 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);
|
|
|
+
|
|
|
+ if (streamPtr->initCheck) return 0; /* Uninitialized structure detected */
|
|
|
+ LZ4_renormDictT(streamPtr, inputSize); /* avoid index overflow */
|
|
|
+ if (acceleration < 1) acceleration = ACCELERATION_DEFAULT;
|
|
|
+
|
|
|
+ /* invalidate tiny dictionaries */
|
|
|
+ if ( (streamPtr->dictSize-1 < 4) /* 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.
|
|
|
+ */
|
|
|
+ memcpy(streamPtr, streamPtr->dictCtx, sizeof(LZ4_stream_t));
|
|
|
+ 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 = dict->dictSize;
|
|
|
+
|
|
|
+ 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) )
|
|
|
+
|
|
|
+/*! 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 */
|
|
|
+ )
|
|
|
+{
|
|
|
+ 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 = (const BYTE*)dictStart + dictSize;
|
|
|
+ const unsigned inc32table[8] = {0, 1, 2, 1, 0, 4, 4, 4};
|
|
|
+ const int dec64table[8] = {0, 0, 0, -1, -4, 1, 2, 3};
|
|
|
+
|
|
|
+ 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*/;
|
|
|
+
|
|
|
+ DEBUGLOG(5, "LZ4_decompress_generic (srcSize:%i, dstSize:%i)", srcSize, outputSize);
|
|
|
+
|
|
|
+ /* Special cases */
|
|
|
+ assert(lowPrefix <= op);
|
|
|
+ assert(src != NULL);
|
|
|
+ if ((endOnInput) && (unlikely(outputSize==0))) return ((srcSize==1) && (*ip==0)) ? 0 : -1; /* Empty output buffer */
|
|
|
+ if ((!endOnInput) && (unlikely(outputSize==0))) return (*ip==0 ? 1 : -1);
|
|
|
+ if ((endOnInput) && unlikely(srcSize==0)) return -1;
|
|
|
+
|
|
|
+ /* Main Loop : decode sequences */
|
|
|
+ while (1) {
|
|
|
+ const BYTE* match;
|
|
|
+ size_t offset;
|
|
|
+
|
|
|
+ unsigned const token = *ip++;
|
|
|
+ size_t 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 */
|
|
|
+ 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. */
|
|
|
+ memcpy(op + 0, match + 0, 8);
|
|
|
+ memcpy(op + 8, match + 8, 8);
|
|
|
+ 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) {
|
|
|
+ unsigned s;
|
|
|
+ if (unlikely(endOnInput ? ip >= iend-RUN_MASK : 0)) goto _output_error; /* overflow detection */
|
|
|
+ do {
|
|
|
+ s = *ip++;
|
|
|
+ length += s;
|
|
|
+ } while ( likely(endOnInput ? ip<iend-RUN_MASK : 1) & (s==255) );
|
|
|
+ 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) && ((cpy>oend-MFLIMIT) || (ip+length>iend-(2+1+LASTLITERALS))) )
|
|
|
+ || ((!endOnInput) && (cpy>oend-WILDCOPYLENGTH)) )
|
|
|
+ {
|
|
|
+ if (partialDecoding) {
|
|
|
+ if (cpy > oend) { cpy = oend; length = oend-op; } /* Partial decoding : stop in the middle of literal segment */
|
|
|
+ if ((endOnInput) && (ip+length > iend)) goto _output_error; /* Error : read attempt beyond end of input buffer */
|
|
|
+ } else {
|
|
|
+ if ((!endOnInput) && (cpy != oend)) goto _output_error; /* Error : block decoding must stop exactly there */
|
|
|
+ if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) goto _output_error; /* Error : input must be consumed */
|
|
|
+ }
|
|
|
+ memcpy(op, ip, length);
|
|
|
+ ip += length;
|
|
|
+ op += length;
|
|
|
+ if (!partialDecoding || (cpy == oend)) {
|
|
|
+ /* Necessarily EOF, due to parsing restrictions */
|
|
|
+ break;
|
|
|
+ }
|
|
|
+
|
|
|
+ } else {
|
|
|
+ LZ4_wildCopy(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 ((checkOffset) && (unlikely(match + dictSize < lowPrefix))) goto _output_error; /* Error : offset outside buffers */
|
|
|
+ if (!partialDecoding) {
|
|
|
+ assert(oend > op);
|
|
|
+ assert(oend - op >= 4);
|
|
|
+ LZ4_write32(op, 0); /* silence an msan warning when offset==0; costs <1%; */
|
|
|
+ } /* note : when partialDecoding, there is no guarantee that at least 4 bytes remain available in output buffer */
|
|
|
+
|
|
|
+ if (length == ML_MASK) {
|
|
|
+ unsigned s;
|
|
|
+ do {
|
|
|
+ s = *ip++;
|
|
|
+ if ((endOnInput) && (ip > iend-LASTLITERALS)) goto _output_error;
|
|
|
+ length += s;
|
|
|
+ } while (s==255);
|
|
|
+ if ((safeDecode) && unlikely((uptrval)(op)+length<(uptrval)op)) goto _output_error; /* overflow detection */
|
|
|
+ }
|
|
|
+ length += MINMATCH;
|
|
|
+
|
|
|
+ /* 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;
|
|
|
+ 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 {
|
|
|
+ memcpy(op, lowPrefix, restSize);
|
|
|
+ op += restSize;
|
|
|
+ } }
|
|
|
+ continue;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* copy match within block */
|
|
|
+ cpy = op + length;
|
|
|
+
|
|
|
+ /* partialDecoding : may not respect endBlock parsing restrictions */
|
|
|
+ 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 {
|
|
|
+ memcpy(op, match, mlen);
|
|
|
+ }
|
|
|
+ op = copyEnd;
|
|
|
+ if (op==oend) break;
|
|
|
+ continue;
|
|
|
+ }
|
|
|
+
|
|
|
+ if (unlikely(offset<8)) {
|
|
|
+ op[0] = match[0];
|
|
|
+ op[1] = match[1];
|
|
|
+ op[2] = match[2];
|
|
|
+ op[3] = match[3];
|
|
|
+ match += inc32table[offset];
|
|
|
+ memcpy(op+4, match, 4);
|
|
|
+ match -= dec64table[offset];
|
|
|
+ } else {
|
|
|
+ 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_wildCopy(op, match, oCopyLimit);
|
|
|
+ match += oCopyLimit - op;
|
|
|
+ op = oCopyLimit;
|
|
|
+ }
|
|
|
+ while (op < cpy) *op++ = *match++;
|
|
|
+ } else {
|
|
|
+ memcpy(op, match, 8);
|
|
|
+ if (length > 16) LZ4_wildCopy(op+8, match+8, cpy);
|
|
|
+ }
|
|
|
+ op = cpy; /* wildcopy correction */
|
|
|
+ }
|
|
|
+
|
|
|
+ /* end of decoding */
|
|
|
+ if (endOnInput)
|
|
|
+ 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_GCC_PPC64LE
|
|
|
+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_GCC_PPC64LE
|
|
|
+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_GCC_PPC64LE
|
|
|
+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_GCC_PPC64LE /* 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_GCC_PPC64LE
|
|
|
+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_GCC_PPC64LE
|
|
|
+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_GCC_PPC64LE
|
|
|
+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));
|
|
|
+ return lz4s;
|
|
|
+}
|
|
|
+
|
|
|
+int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream)
|
|
|
+{
|
|
|
+ if (!LZ4_stream) 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_GCC_PPC64LE
|
|
|
+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 = 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 += 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 = result;
|
|
|
+ lz4sd->prefixEnd = (BYTE*)dest + result;
|
|
|
+ }
|
|
|
+
|
|
|
+ return result;
|
|
|
+}
|
|
|
+
|
|
|
+LZ4_FORCE_O2_GCC_PPC64LE
|
|
|
+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;
|
|
|
+
|
|
|
+ if (lz4sd->prefixSize == 0) {
|
|
|
+ assert(lz4sd->extDictSize == 0);
|
|
|
+ result = LZ4_decompress_fast(source, dest, originalSize);
|
|
|
+ if (result <= 0) return result;
|
|
|
+ lz4sd->prefixSize = 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 += 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 = 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);
|
|
|
+ return LZ4_decompress_safe_withSmallPrefix(source, dest, compressedSize, maxOutputSize, dictSize);
|
|
|
+ }
|
|
|
+ return LZ4_decompress_safe_forceExtDict(source, dest, compressedSize, maxOutputSize, dictStart, 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);
|
|
|
+ return LZ4_decompress_fast_extDict(source, dest, originalSize, dictStart, 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* source, char* dest, int inputSize)
|
|
|
+{
|
|
|
+ return LZ4_compress_default(source, dest, inputSize, LZ4_compressBound(inputSize));
|
|
|
+}
|
|
|
+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() { 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 */
|
NX