1 | /* |
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2 | LZ4 - Fast LZ compression algorithm |
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3 | Copyright (C) 2011-2015, Yann Collet. |
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4 | |
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5 | BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) |
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6 | |
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7 | Redistribution and use in source and binary forms, with or without |
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8 | modification, are permitted provided that the following conditions are |
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9 | met: |
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10 | |
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11 | * Redistributions of source code must retain the above copyright |
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12 | notice, this list of conditions and the following disclaimer. |
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13 | * Redistributions in binary form must reproduce the above |
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14 | copyright notice, this list of conditions and the following disclaimer |
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15 | in the documentation and/or other materials provided with the |
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16 | distribution. |
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17 | |
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18 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
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19 | "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
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20 | LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
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21 | A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
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22 | OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
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23 | SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
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24 | LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
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25 | DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
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26 | THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
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27 | (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
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28 | OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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29 | |
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30 | You can contact the author at : |
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31 | - LZ4 source repository : https://github.com/Cyan4973/lz4 |
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32 | - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c |
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33 | */ |
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34 | |
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35 | |
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36 | /************************************** |
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37 | * Tuning parameters |
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38 | **************************************/ |
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39 | /* |
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40 | * HEAPMODE : |
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41 | * Select how default compression functions will allocate memory for their hash table, |
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42 | * in memory stack (0:default, fastest), or in memory heap (1:requires malloc()). |
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43 | */ |
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44 | #define HEAPMODE 0 |
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45 | |
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46 | /* |
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47 | * ACCELERATION_DEFAULT : |
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48 | * Select "acceleration" for LZ4_compress_fast() when parameter value <= 0 |
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49 | */ |
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50 | #define ACCELERATION_DEFAULT 1 |
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51 | |
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52 | |
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53 | /************************************** |
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54 | * CPU Feature Detection |
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55 | **************************************/ |
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56 | /* LZ4_FORCE_MEMORY_ACCESS |
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57 | * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable. |
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58 | * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal. |
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59 | * The below switch allow to select different access method for improved performance. |
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60 | * Method 0 (default) : use `memcpy()`. Safe and portable. |
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61 | * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable). |
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62 | * This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`. |
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63 | * Method 2 : direct access. This method is portable but violate C standard. |
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64 | * It can generate buggy code on targets which generate assembly depending on alignment. |
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65 | * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6) |
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66 | * See http://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details. |
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67 | * Prefer these methods in priority order (0 > 1 > 2) |
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68 | */ |
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69 | #ifndef LZ4_FORCE_MEMORY_ACCESS /* can be defined externally, on command line for example */ |
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70 | # if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) ) |
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71 | # define LZ4_FORCE_MEMORY_ACCESS 2 |
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72 | # elif defined(__INTEL_COMPILER) || \ |
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73 | (defined(__GNUC__) && ( defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__) )) |
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74 | # define LZ4_FORCE_MEMORY_ACCESS 1 |
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75 | # endif |
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76 | #endif |
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77 | |
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78 | /* |
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79 | * LZ4_FORCE_SW_BITCOUNT |
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80 | * Define this parameter if your target system or compiler does not support hardware bit count |
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81 | */ |
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82 | #if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for Windows CE does not support Hardware bit count */ |
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83 | # define LZ4_FORCE_SW_BITCOUNT |
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84 | #endif |
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85 | |
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86 | |
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87 | /************************************** |
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88 | * Includes |
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89 | **************************************/ |
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90 | #include "lz4.h" |
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91 | |
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92 | |
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93 | /************************************** |
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94 | * Compiler Options |
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95 | **************************************/ |
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96 | #ifdef _MSC_VER /* Visual Studio */ |
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97 | # define FORCE_INLINE static __forceinline |
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98 | # include <intrin.h> |
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99 | # pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ |
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100 | # pragma warning(disable : 4293) /* disable: C4293: too large shift (32-bits) */ |
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101 | #else |
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102 | # if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */ |
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103 | # if defined(__GNUC__) || defined(__clang__) |
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104 | # define FORCE_INLINE static inline __attribute__((always_inline)) |
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105 | # else |
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106 | # define FORCE_INLINE static inline |
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107 | # endif |
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108 | # else |
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109 | # define FORCE_INLINE static |
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110 | # endif /* __STDC_VERSION__ */ |
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111 | #endif /* _MSC_VER */ |
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112 | |
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113 | /* LZ4_GCC_VERSION is defined into lz4.h */ |
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114 | #if (LZ4_GCC_VERSION >= 302) || (__INTEL_COMPILER >= 800) || defined(__clang__) |
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115 | # define expect(expr,value) (__builtin_expect ((expr),(value)) ) |
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116 | #else |
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117 | # define expect(expr,value) (expr) |
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118 | #endif |
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119 | |
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120 | #define likely(expr) expect((expr) != 0, 1) |
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121 | #define unlikely(expr) expect((expr) != 0, 0) |
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122 | |
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123 | |
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124 | /************************************** |
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125 | * Memory routines |
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126 | **************************************/ |
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127 | #include <stdlib.h> /* malloc, calloc, free */ |
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128 | #define ALLOCATOR(n,s) calloc(n,s) |
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129 | #define FREEMEM free |
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130 | #include <string.h> /* memset, memcpy */ |
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131 | #define MEM_INIT memset |
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132 | |
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133 | |
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134 | /************************************** |
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135 | * Basic Types |
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136 | **************************************/ |
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137 | #if defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */ |
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138 | # include <stdint.h> |
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139 | typedef uint8_t BYTE; |
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140 | typedef uint16_t U16; |
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141 | typedef uint32_t U32; |
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142 | typedef int32_t S32; |
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143 | typedef uint64_t U64; |
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144 | #else |
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145 | typedef unsigned char BYTE; |
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146 | typedef unsigned short U16; |
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147 | typedef unsigned int U32; |
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148 | typedef signed int S32; |
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149 | typedef unsigned long long U64; |
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150 | #endif |
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151 | |
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152 | |
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153 | /************************************** |
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154 | * Reading and writing into memory |
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155 | **************************************/ |
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156 | #define STEPSIZE sizeof(size_t) |
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157 | |
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158 | static unsigned LZ4_64bits(void) { return sizeof(void*)==8; } |
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159 | |
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160 | static unsigned LZ4_isLittleEndian(void) |
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161 | { |
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162 | const union { U32 i; BYTE c[4]; } one = { 1 }; // don't use static : performance detrimental |
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163 | return one.c[0]; |
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164 | } |
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165 | |
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166 | |
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167 | #if defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==2) |
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168 | |
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169 | static U16 LZ4_read16(const void* memPtr) { return *(const U16*) memPtr; } |
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170 | static U32 LZ4_read32(const void* memPtr) { return *(const U32*) memPtr; } |
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171 | static size_t LZ4_read_ARCH(const void* memPtr) { return *(const size_t*) memPtr; } |
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172 | |
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173 | static void LZ4_write16(void* memPtr, U16 value) { *(U16*)memPtr = value; } |
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174 | |
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175 | #elif defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS==1) |
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176 | |
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177 | /* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */ |
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178 | /* currently only defined for gcc and icc */ |
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179 | typedef union { U16 u16; U32 u32; size_t uArch; } __attribute__((packed)) unalign; |
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180 | |
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181 | static U16 LZ4_read16(const void* ptr) { return ((const unalign*)ptr)->u16; } |
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182 | static U32 LZ4_read32(const void* ptr) { return ((const unalign*)ptr)->u32; } |
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183 | static size_t LZ4_read_ARCH(const void* ptr) { return ((const unalign*)ptr)->uArch; } |
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184 | |
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185 | static void LZ4_write16(void* memPtr, U16 value) { ((unalign*)memPtr)->u16 = value; } |
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186 | |
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187 | #else |
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188 | |
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189 | static U16 LZ4_read16(const void* memPtr) |
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190 | { |
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191 | U16 val; memcpy(&val, memPtr, sizeof(val)); return val; |
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192 | } |
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193 | |
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194 | static U32 LZ4_read32(const void* memPtr) |
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195 | { |
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196 | U32 val; memcpy(&val, memPtr, sizeof(val)); return val; |
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197 | } |
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198 | |
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199 | static size_t LZ4_read_ARCH(const void* memPtr) |
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200 | { |
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201 | size_t val; memcpy(&val, memPtr, sizeof(val)); return val; |
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202 | } |
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203 | |
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204 | static void LZ4_write16(void* memPtr, U16 value) |
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205 | { |
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206 | memcpy(memPtr, &value, sizeof(value)); |
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207 | } |
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208 | |
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209 | #endif // LZ4_FORCE_MEMORY_ACCESS |
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210 | |
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211 | |
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212 | static U16 LZ4_readLE16(const void* memPtr) |
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213 | { |
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214 | if (LZ4_isLittleEndian()) |
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215 | { |
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216 | return LZ4_read16(memPtr); |
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217 | } |
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218 | else |
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219 | { |
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220 | const BYTE* p = (const BYTE*)memPtr; |
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221 | return (U16)((U16)p[0] + (p[1]<<8)); |
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222 | } |
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223 | } |
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224 | |
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225 | static void LZ4_writeLE16(void* memPtr, U16 value) |
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226 | { |
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227 | if (LZ4_isLittleEndian()) |
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228 | { |
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229 | LZ4_write16(memPtr, value); |
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230 | } |
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231 | else |
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232 | { |
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233 | BYTE* p = (BYTE*)memPtr; |
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234 | p[0] = (BYTE) value; |
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235 | p[1] = (BYTE)(value>>8); |
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236 | } |
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237 | } |
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238 | |
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239 | static void LZ4_copy8(void* dst, const void* src) |
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240 | { |
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241 | memcpy(dst,src,8); |
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242 | } |
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243 | |
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244 | /* customized variant of memcpy, which can overwrite up to 7 bytes beyond dstEnd */ |
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245 | static void LZ4_wildCopy(void* dstPtr, const void* srcPtr, void* dstEnd) |
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246 | { |
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247 | BYTE* d = (BYTE*)dstPtr; |
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248 | const BYTE* s = (const BYTE*)srcPtr; |
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249 | BYTE* const e = (BYTE*)dstEnd; |
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250 | |
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251 | #if 0 |
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252 | const size_t l2 = 8 - (((size_t)d) & (sizeof(void*)-1)); |
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253 | LZ4_copy8(d,s); if (d>e-9) return; |
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254 | d+=l2; s+=l2; |
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255 | #endif /* join to align */ |
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256 | |
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257 | do { LZ4_copy8(d,s); d+=8; s+=8; } while (d<e); |
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258 | } |
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259 | |
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260 | |
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261 | /************************************** |
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262 | * Common Constants |
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263 | **************************************/ |
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264 | #define MINMATCH 4 |
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265 | |
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266 | #define WILDCOPYLENGTH 8 |
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267 | #define LASTLITERALS 5 |
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268 | #define MFLIMIT (WILDCOPYLENGTH+MINMATCH) |
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269 | static const int LZ4_minLength = (MFLIMIT+1); |
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270 | |
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271 | #define KB *(1 <<10) |
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272 | #define MB *(1 <<20) |
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273 | #define GB *(1U<<30) |
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274 | |
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275 | #define MAXD_LOG 16 |
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276 | #define MAX_DISTANCE ((1 << MAXD_LOG) - 1) |
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277 | |
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278 | #define ML_BITS 4 |
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279 | #define ML_MASK ((1U<<ML_BITS)-1) |
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280 | #define RUN_BITS (8-ML_BITS) |
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281 | #define RUN_MASK ((1U<<RUN_BITS)-1) |
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282 | |
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283 | |
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284 | /************************************** |
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285 | * Common Utils |
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286 | **************************************/ |
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287 | #define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */ |
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288 | |
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289 | |
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290 | /************************************** |
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291 | * Common functions |
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292 | **************************************/ |
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293 | static unsigned LZ4_NbCommonBytes (register size_t val) |
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294 | { |
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295 | if (LZ4_isLittleEndian()) |
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296 | { |
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297 | if (LZ4_64bits()) |
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298 | { |
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299 | # if defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT) |
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300 | unsigned long r = 0; |
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301 | _BitScanForward64( &r, (U64)val ); |
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302 | return (int)(r>>3); |
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303 | # elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) && !defined(LZ4_FORCE_SW_BITCOUNT) |
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304 | return (__builtin_ctzll((U64)val) >> 3); |
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305 | # else |
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306 | static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2, 0, 3, 1, 3, 1, 4, 2, 7, 0, 2, 3, 6, 1, 5, 3, 5, 1, 3, 4, 4, 2, 5, 6, 7, 7, 0, 1, 2, 3, 3, 4, 6, 2, 6, 5, 5, 3, 4, 5, 6, 7, 1, 2, 4, 6, 4, 4, 5, 7, 2, 6, 5, 7, 6, 7, 7 }; |
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307 | return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58]; |
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308 | # endif |
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309 | } |
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310 | else /* 32 bits */ |
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311 | { |
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312 | # if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT) |
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313 | unsigned long r; |
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314 | _BitScanForward( &r, (U32)val ); |
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315 | return (int)(r>>3); |
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316 | # elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) && !defined(LZ4_FORCE_SW_BITCOUNT) |
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317 | return (__builtin_ctz((U32)val) >> 3); |
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318 | # else |
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319 | 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 }; |
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320 | return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27]; |
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321 | # endif |
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322 | } |
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323 | } |
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324 | else /* Big Endian CPU */ |
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325 | { |
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326 | if (LZ4_64bits()) |
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327 | { |
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328 | # if defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT) |
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329 | unsigned long r = 0; |
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330 | _BitScanReverse64( &r, val ); |
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331 | return (unsigned)(r>>3); |
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332 | # elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) && !defined(LZ4_FORCE_SW_BITCOUNT) |
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333 | return (__builtin_clzll((U64)val) >> 3); |
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334 | # else |
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335 | unsigned r; |
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336 | if (!(val>>32)) { r=4; } else { r=0; val>>=32; } |
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337 | if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; } |
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338 | r += (!val); |
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339 | return r; |
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340 | # endif |
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341 | } |
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342 | else /* 32 bits */ |
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343 | { |
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344 | # if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT) |
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345 | unsigned long r = 0; |
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346 | _BitScanReverse( &r, (unsigned long)val ); |
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347 | return (unsigned)(r>>3); |
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348 | # elif (defined(__clang__) || (LZ4_GCC_VERSION >= 304)) && !defined(LZ4_FORCE_SW_BITCOUNT) |
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349 | return (__builtin_clz((U32)val) >> 3); |
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350 | # else |
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351 | unsigned r; |
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352 | if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; } |
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353 | r += (!val); |
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354 | return r; |
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355 | # endif |
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356 | } |
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357 | } |
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358 | } |
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359 | |
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360 | static unsigned LZ4_count(const BYTE* pIn, const BYTE* pMatch, const BYTE* pInLimit) |
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361 | { |
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362 | const BYTE* const pStart = pIn; |
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363 | |
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364 | while (likely(pIn<pInLimit-(STEPSIZE-1))) |
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365 | { |
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366 | size_t diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn); |
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367 | if (!diff) { pIn+=STEPSIZE; pMatch+=STEPSIZE; continue; } |
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368 | pIn += LZ4_NbCommonBytes(diff); |
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369 | return (unsigned)(pIn - pStart); |
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370 | } |
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371 | |
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372 | if (LZ4_64bits()) if ((pIn<(pInLimit-3)) && (LZ4_read32(pMatch) == LZ4_read32(pIn))) { pIn+=4; pMatch+=4; } |
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373 | if ((pIn<(pInLimit-1)) && (LZ4_read16(pMatch) == LZ4_read16(pIn))) { pIn+=2; pMatch+=2; } |
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374 | if ((pIn<pInLimit) && (*pMatch == *pIn)) pIn++; |
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375 | return (unsigned)(pIn - pStart); |
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376 | } |
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377 | |
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378 | |
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379 | #ifndef LZ4_COMMONDEFS_ONLY |
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380 | /************************************** |
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381 | * Local Constants |
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382 | **************************************/ |
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383 | #define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2) |
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384 | #define HASHTABLESIZE (1 << LZ4_MEMORY_USAGE) |
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385 | #define HASH_SIZE_U32 (1 << LZ4_HASHLOG) /* required as macro for static allocation */ |
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386 | |
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387 | static const int LZ4_64Klimit = ((64 KB) + (MFLIMIT-1)); |
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388 | static const U32 LZ4_skipTrigger = 6; /* Increase this value ==> compression run slower on incompressible data */ |
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389 | |
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390 | |
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391 | /************************************** |
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392 | * Local Structures and types |
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393 | **************************************/ |
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394 | typedef struct { |
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395 | U32 hashTable[HASH_SIZE_U32]; |
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396 | U32 currentOffset; |
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397 | U32 initCheck; |
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398 | const BYTE* dictionary; |
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399 | BYTE* bufferStart; /* obsolete, used for slideInputBuffer */ |
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400 | U32 dictSize; |
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401 | } LZ4_stream_t_internal; |
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402 | |
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403 | typedef enum { notLimited = 0, limitedOutput = 1 } limitedOutput_directive; |
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404 | typedef enum { byPtr, byU32, byU16 } tableType_t; |
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405 | |
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406 | typedef enum { noDict = 0, withPrefix64k, usingExtDict } dict_directive; |
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407 | typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive; |
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408 | |
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409 | typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive; |
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410 | typedef enum { full = 0, partial = 1 } earlyEnd_directive; |
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411 | |
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412 | |
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413 | /************************************** |
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414 | * Local Utils |
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415 | **************************************/ |
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416 | int LZ4_versionNumber (void) { return LZ4_VERSION_NUMBER; } |
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417 | int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); } |
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418 | int LZ4_sizeofState() { return LZ4_STREAMSIZE; } |
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419 | |
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420 | |
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421 | |
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422 | /******************************** |
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423 | * Compression functions |
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424 | ********************************/ |
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425 | |
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426 | static U32 LZ4_hashSequence(U32 sequence, tableType_t const tableType) |
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427 | { |
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428 | if (tableType == byU16) |
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429 | return (((sequence) * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1))); |
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430 | else |
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431 | return (((sequence) * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG)); |
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432 | } |
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433 | |
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434 | static const U64 prime5bytes = 889523592379ULL; |
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435 | static U32 LZ4_hashSequence64(size_t sequence, tableType_t const tableType) |
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436 | { |
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437 | const U32 hashLog = (tableType == byU16) ? LZ4_HASHLOG+1 : LZ4_HASHLOG; |
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438 | const U32 hashMask = (1<<hashLog) - 1; |
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439 | return ((sequence * prime5bytes) >> (40 - hashLog)) & hashMask; |
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440 | } |
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441 | |
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442 | static U32 LZ4_hashSequenceT(size_t sequence, tableType_t const tableType) |
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443 | { |
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444 | if (LZ4_64bits()) |
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445 | return LZ4_hashSequence64(sequence, tableType); |
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446 | return LZ4_hashSequence((U32)sequence, tableType); |
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447 | } |
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448 | |
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449 | static U32 LZ4_hashPosition(const void* p, tableType_t tableType) { return LZ4_hashSequenceT(LZ4_read_ARCH(p), tableType); } |
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450 | |
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451 | static void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase, tableType_t const tableType, const BYTE* srcBase) |
---|
452 | { |
---|
453 | switch (tableType) |
---|
454 | { |
---|
455 | case byPtr: { const BYTE** hashTable = (const BYTE**)tableBase; hashTable[h] = p; return; } |
---|
456 | case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); return; } |
---|
457 | case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); return; } |
---|
458 | } |
---|
459 | } |
---|
460 | |
---|
461 | static void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase) |
---|
462 | { |
---|
463 | U32 h = LZ4_hashPosition(p, tableType); |
---|
464 | LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase); |
---|
465 | } |
---|
466 | |
---|
467 | static const BYTE* LZ4_getPositionOnHash(U32 h, void* tableBase, tableType_t tableType, const BYTE* srcBase) |
---|
468 | { |
---|
469 | if (tableType == byPtr) { const BYTE** hashTable = (const BYTE**) tableBase; return hashTable[h]; } |
---|
470 | if (tableType == byU32) { U32* hashTable = (U32*) tableBase; return hashTable[h] + srcBase; } |
---|
471 | { U16* hashTable = (U16*) tableBase; return hashTable[h] + srcBase; } /* default, to ensure a return */ |
---|
472 | } |
---|
473 | |
---|
474 | static const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase) |
---|
475 | { |
---|
476 | U32 h = LZ4_hashPosition(p, tableType); |
---|
477 | return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase); |
---|
478 | } |
---|
479 | |
---|
480 | FORCE_INLINE int LZ4_compress_generic( |
---|
481 | void* const ctx, |
---|
482 | const char* const source, |
---|
483 | char* const dest, |
---|
484 | const int inputSize, |
---|
485 | const int maxOutputSize, |
---|
486 | const limitedOutput_directive outputLimited, |
---|
487 | const tableType_t tableType, |
---|
488 | const dict_directive dict, |
---|
489 | const dictIssue_directive dictIssue, |
---|
490 | const U32 acceleration) |
---|
491 | { |
---|
492 | LZ4_stream_t_internal* const dictPtr = (LZ4_stream_t_internal*)ctx; |
---|
493 | |
---|
494 | const BYTE* ip = (const BYTE*) source; |
---|
495 | const BYTE* base; |
---|
496 | const BYTE* lowLimit; |
---|
497 | const BYTE* const lowRefLimit = ip - dictPtr->dictSize; |
---|
498 | const BYTE* const dictionary = dictPtr->dictionary; |
---|
499 | const BYTE* const dictEnd = dictionary + dictPtr->dictSize; |
---|
500 | const size_t dictDelta = dictEnd - (const BYTE*)source; |
---|
501 | const BYTE* anchor = (const BYTE*) source; |
---|
502 | const BYTE* const iend = ip + inputSize; |
---|
503 | const BYTE* const mflimit = iend - MFLIMIT; |
---|
504 | const BYTE* const matchlimit = iend - LASTLITERALS; |
---|
505 | |
---|
506 | BYTE* op = (BYTE*) dest; |
---|
507 | BYTE* const olimit = op + maxOutputSize; |
---|
508 | |
---|
509 | U32 forwardH; |
---|
510 | size_t refDelta=0; |
---|
511 | |
---|
512 | /* Init conditions */ |
---|
513 | if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported input size, too large (or negative) */ |
---|
514 | switch(dict) |
---|
515 | { |
---|
516 | case noDict: |
---|
517 | default: |
---|
518 | base = (const BYTE*)source; |
---|
519 | lowLimit = (const BYTE*)source; |
---|
520 | break; |
---|
521 | case withPrefix64k: |
---|
522 | base = (const BYTE*)source - dictPtr->currentOffset; |
---|
523 | lowLimit = (const BYTE*)source - dictPtr->dictSize; |
---|
524 | break; |
---|
525 | case usingExtDict: |
---|
526 | base = (const BYTE*)source - dictPtr->currentOffset; |
---|
527 | lowLimit = (const BYTE*)source; |
---|
528 | break; |
---|
529 | } |
---|
530 | if ((tableType == byU16) && (inputSize>=LZ4_64Klimit)) return 0; /* Size too large (not within 64K limit) */ |
---|
531 | if (inputSize<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */ |
---|
532 | |
---|
533 | /* First Byte */ |
---|
534 | LZ4_putPosition(ip, ctx, tableType, base); |
---|
535 | ip++; forwardH = LZ4_hashPosition(ip, tableType); |
---|
536 | |
---|
537 | /* Main Loop */ |
---|
538 | for ( ; ; ) |
---|
539 | { |
---|
540 | const BYTE* match; |
---|
541 | BYTE* token; |
---|
542 | { |
---|
543 | const BYTE* forwardIp = ip; |
---|
544 | unsigned step = 1; |
---|
545 | unsigned searchMatchNb = acceleration << LZ4_skipTrigger; |
---|
546 | |
---|
547 | /* Find a match */ |
---|
548 | do { |
---|
549 | U32 h = forwardH; |
---|
550 | ip = forwardIp; |
---|
551 | forwardIp += step; |
---|
552 | step = (searchMatchNb++ >> LZ4_skipTrigger); |
---|
553 | |
---|
554 | if (unlikely(forwardIp > mflimit)) goto _last_literals; |
---|
555 | |
---|
556 | match = LZ4_getPositionOnHash(h, ctx, tableType, base); |
---|
557 | if (dict==usingExtDict) |
---|
558 | { |
---|
559 | if (match<(const BYTE*)source) |
---|
560 | { |
---|
561 | refDelta = dictDelta; |
---|
562 | lowLimit = dictionary; |
---|
563 | } |
---|
564 | else |
---|
565 | { |
---|
566 | refDelta = 0; |
---|
567 | lowLimit = (const BYTE*)source; |
---|
568 | } |
---|
569 | } |
---|
570 | forwardH = LZ4_hashPosition(forwardIp, tableType); |
---|
571 | LZ4_putPositionOnHash(ip, h, ctx, tableType, base); |
---|
572 | |
---|
573 | } while ( ((dictIssue==dictSmall) ? (match < lowRefLimit) : 0) |
---|
574 | || ((tableType==byU16) ? 0 : (match + MAX_DISTANCE < ip)) |
---|
575 | || (LZ4_read32(match+refDelta) != LZ4_read32(ip)) ); |
---|
576 | } |
---|
577 | |
---|
578 | /* Catch up */ |
---|
579 | while ((ip>anchor) && (match+refDelta > lowLimit) && (unlikely(ip[-1]==match[refDelta-1]))) { ip--; match--; } |
---|
580 | |
---|
581 | { |
---|
582 | /* Encode Literal length */ |
---|
583 | unsigned litLength = (unsigned)(ip - anchor); |
---|
584 | token = op++; |
---|
585 | if ((outputLimited) && (unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength/255) > olimit))) |
---|
586 | return 0; /* Check output limit */ |
---|
587 | if (litLength>=RUN_MASK) |
---|
588 | { |
---|
589 | int len = (int)litLength-RUN_MASK; |
---|
590 | *token=(RUN_MASK<<ML_BITS); |
---|
591 | for(; len >= 255 ; len-=255) *op++ = 255; |
---|
592 | *op++ = (BYTE)len; |
---|
593 | } |
---|
594 | else *token = (BYTE)(litLength<<ML_BITS); |
---|
595 | |
---|
596 | /* Copy Literals */ |
---|
597 | LZ4_wildCopy(op, anchor, op+litLength); |
---|
598 | op+=litLength; |
---|
599 | } |
---|
600 | |
---|
601 | _next_match: |
---|
602 | /* Encode Offset */ |
---|
603 | LZ4_writeLE16(op, (U16)(ip-match)); op+=2; |
---|
604 | |
---|
605 | /* Encode MatchLength */ |
---|
606 | { |
---|
607 | unsigned matchLength; |
---|
608 | |
---|
609 | if ((dict==usingExtDict) && (lowLimit==dictionary)) |
---|
610 | { |
---|
611 | const BYTE* limit; |
---|
612 | match += refDelta; |
---|
613 | limit = ip + (dictEnd-match); |
---|
614 | if (limit > matchlimit) limit = matchlimit; |
---|
615 | matchLength = LZ4_count(ip+MINMATCH, match+MINMATCH, limit); |
---|
616 | ip += MINMATCH + matchLength; |
---|
617 | if (ip==limit) |
---|
618 | { |
---|
619 | unsigned more = LZ4_count(ip, (const BYTE*)source, matchlimit); |
---|
620 | matchLength += more; |
---|
621 | ip += more; |
---|
622 | } |
---|
623 | } |
---|
624 | else |
---|
625 | { |
---|
626 | matchLength = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit); |
---|
627 | ip += MINMATCH + matchLength; |
---|
628 | } |
---|
629 | |
---|
630 | if ((outputLimited) && (unlikely(op + (1 + LASTLITERALS) + (matchLength>>8) > olimit))) |
---|
631 | return 0; /* Check output limit */ |
---|
632 | if (matchLength>=ML_MASK) |
---|
633 | { |
---|
634 | *token += ML_MASK; |
---|
635 | matchLength -= ML_MASK; |
---|
636 | for (; matchLength >= 510 ; matchLength-=510) { *op++ = 255; *op++ = 255; } |
---|
637 | if (matchLength >= 255) { matchLength-=255; *op++ = 255; } |
---|
638 | *op++ = (BYTE)matchLength; |
---|
639 | } |
---|
640 | else *token += (BYTE)(matchLength); |
---|
641 | } |
---|
642 | |
---|
643 | anchor = ip; |
---|
644 | |
---|
645 | /* Test end of chunk */ |
---|
646 | if (ip > mflimit) break; |
---|
647 | |
---|
648 | /* Fill table */ |
---|
649 | LZ4_putPosition(ip-2, ctx, tableType, base); |
---|
650 | |
---|
651 | /* Test next position */ |
---|
652 | match = LZ4_getPosition(ip, ctx, tableType, base); |
---|
653 | if (dict==usingExtDict) |
---|
654 | { |
---|
655 | if (match<(const BYTE*)source) |
---|
656 | { |
---|
657 | refDelta = dictDelta; |
---|
658 | lowLimit = dictionary; |
---|
659 | } |
---|
660 | else |
---|
661 | { |
---|
662 | refDelta = 0; |
---|
663 | lowLimit = (const BYTE*)source; |
---|
664 | } |
---|
665 | } |
---|
666 | LZ4_putPosition(ip, ctx, tableType, base); |
---|
667 | if ( ((dictIssue==dictSmall) ? (match>=lowRefLimit) : 1) |
---|
668 | && (match+MAX_DISTANCE>=ip) |
---|
669 | && (LZ4_read32(match+refDelta)==LZ4_read32(ip)) ) |
---|
670 | { token=op++; *token=0; goto _next_match; } |
---|
671 | |
---|
672 | /* Prepare next loop */ |
---|
673 | forwardH = LZ4_hashPosition(++ip, tableType); |
---|
674 | } |
---|
675 | |
---|
676 | _last_literals: |
---|
677 | /* Encode Last Literals */ |
---|
678 | { |
---|
679 | const size_t lastRun = (size_t)(iend - anchor); |
---|
680 | if ((outputLimited) && ((op - (BYTE*)dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize)) |
---|
681 | return 0; /* Check output limit */ |
---|
682 | if (lastRun >= RUN_MASK) |
---|
683 | { |
---|
684 | size_t accumulator = lastRun - RUN_MASK; |
---|
685 | *op++ = RUN_MASK << ML_BITS; |
---|
686 | for(; accumulator >= 255 ; accumulator-=255) *op++ = 255; |
---|
687 | *op++ = (BYTE) accumulator; |
---|
688 | } |
---|
689 | else |
---|
690 | { |
---|
691 | *op++ = (BYTE)(lastRun<<ML_BITS); |
---|
692 | } |
---|
693 | memcpy(op, anchor, lastRun); |
---|
694 | op += lastRun; |
---|
695 | } |
---|
696 | |
---|
697 | /* End */ |
---|
698 | return (int) (((char*)op)-dest); |
---|
699 | } |
---|
700 | |
---|
701 | |
---|
702 | int LZ4_compress_fast_extState(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration) |
---|
703 | { |
---|
704 | LZ4_resetStream((LZ4_stream_t*)state); |
---|
705 | if (acceleration < 1) acceleration = ACCELERATION_DEFAULT; |
---|
706 | |
---|
707 | if (maxOutputSize >= LZ4_compressBound(inputSize)) |
---|
708 | { |
---|
709 | if (inputSize < LZ4_64Klimit) |
---|
710 | return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue, acceleration); |
---|
711 | else |
---|
712 | return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue, acceleration); |
---|
713 | } |
---|
714 | else |
---|
715 | { |
---|
716 | if (inputSize < LZ4_64Klimit) |
---|
717 | return LZ4_compress_generic(state, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration); |
---|
718 | else |
---|
719 | return LZ4_compress_generic(state, source, dest, inputSize, maxOutputSize, limitedOutput, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue, acceleration); |
---|
720 | } |
---|
721 | } |
---|
722 | |
---|
723 | |
---|
724 | int LZ4_compress_fast(const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration) |
---|
725 | { |
---|
726 | #if (HEAPMODE) |
---|
727 | void* ctxPtr = ALLOCATOR(1, sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */ |
---|
728 | #else |
---|
729 | LZ4_stream_t ctx; |
---|
730 | void* ctxPtr = &ctx; |
---|
731 | #endif |
---|
732 | |
---|
733 | int result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration); |
---|
734 | |
---|
735 | #if (HEAPMODE) |
---|
736 | FREEMEM(ctxPtr); |
---|
737 | #endif |
---|
738 | return result; |
---|
739 | } |
---|
740 | |
---|
741 | |
---|
742 | int LZ4_compress_default(const char* source, char* dest, int inputSize, int maxOutputSize) |
---|
743 | { |
---|
744 | return LZ4_compress_fast(source, dest, inputSize, maxOutputSize, 1); |
---|
745 | } |
---|
746 | |
---|
747 | |
---|
748 | /* hidden debug function */ |
---|
749 | /* strangely enough, gcc generates faster code when this function is uncommented, even if unused */ |
---|
750 | int LZ4_compress_fast_force(const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration) |
---|
751 | { |
---|
752 | LZ4_stream_t ctx; |
---|
753 | |
---|
754 | LZ4_resetStream(&ctx); |
---|
755 | |
---|
756 | if (inputSize < LZ4_64Klimit) |
---|
757 | return LZ4_compress_generic(&ctx, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration); |
---|
758 | else |
---|
759 | return LZ4_compress_generic(&ctx, source, dest, inputSize, maxOutputSize, limitedOutput, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue, acceleration); |
---|
760 | } |
---|
761 | |
---|
762 | |
---|
763 | /******************************** |
---|
764 | * destSize variant |
---|
765 | ********************************/ |
---|
766 | |
---|
767 | static int LZ4_compress_destSize_generic( |
---|
768 | void* const ctx, |
---|
769 | const char* const src, |
---|
770 | char* const dst, |
---|
771 | int* const srcSizePtr, |
---|
772 | const int targetDstSize, |
---|
773 | const tableType_t tableType) |
---|
774 | { |
---|
775 | const BYTE* ip = (const BYTE*) src; |
---|
776 | const BYTE* base = (const BYTE*) src; |
---|
777 | const BYTE* lowLimit = (const BYTE*) src; |
---|
778 | const BYTE* anchor = ip; |
---|
779 | const BYTE* const iend = ip + *srcSizePtr; |
---|
780 | const BYTE* const mflimit = iend - MFLIMIT; |
---|
781 | const BYTE* const matchlimit = iend - LASTLITERALS; |
---|
782 | |
---|
783 | BYTE* op = (BYTE*) dst; |
---|
784 | BYTE* const oend = op + targetDstSize; |
---|
785 | BYTE* const oMaxLit = op + targetDstSize - 2 /* offset */ - 8 /* because 8+MINMATCH==MFLIMIT */ - 1 /* token */; |
---|
786 | BYTE* const oMaxMatch = op + targetDstSize - (LASTLITERALS + 1 /* token */); |
---|
787 | BYTE* const oMaxSeq = oMaxLit - 1 /* token */; |
---|
788 | |
---|
789 | U32 forwardH; |
---|
790 | |
---|
791 | |
---|
792 | /* Init conditions */ |
---|
793 | if (targetDstSize < 1) return 0; /* Impossible to store anything */ |
---|
794 | if ((U32)*srcSizePtr > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported input size, too large (or negative) */ |
---|
795 | if ((tableType == byU16) && (*srcSizePtr>=LZ4_64Klimit)) return 0; /* Size too large (not within 64K limit) */ |
---|
796 | if (*srcSizePtr<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */ |
---|
797 | |
---|
798 | /* First Byte */ |
---|
799 | *srcSizePtr = 0; |
---|
800 | LZ4_putPosition(ip, ctx, tableType, base); |
---|
801 | ip++; forwardH = LZ4_hashPosition(ip, tableType); |
---|
802 | |
---|
803 | /* Main Loop */ |
---|
804 | for ( ; ; ) |
---|
805 | { |
---|
806 | const BYTE* match; |
---|
807 | BYTE* token; |
---|
808 | { |
---|
809 | const BYTE* forwardIp = ip; |
---|
810 | unsigned step = 1; |
---|
811 | unsigned searchMatchNb = 1 << LZ4_skipTrigger; |
---|
812 | |
---|
813 | /* Find a match */ |
---|
814 | do { |
---|
815 | U32 h = forwardH; |
---|
816 | ip = forwardIp; |
---|
817 | forwardIp += step; |
---|
818 | step = (searchMatchNb++ >> LZ4_skipTrigger); |
---|
819 | |
---|
820 | if (unlikely(forwardIp > mflimit)) |
---|
821 | goto _last_literals; |
---|
822 | |
---|
823 | match = LZ4_getPositionOnHash(h, ctx, tableType, base); |
---|
824 | forwardH = LZ4_hashPosition(forwardIp, tableType); |
---|
825 | LZ4_putPositionOnHash(ip, h, ctx, tableType, base); |
---|
826 | |
---|
827 | } while ( ((tableType==byU16) ? 0 : (match + MAX_DISTANCE < ip)) |
---|
828 | || (LZ4_read32(match) != LZ4_read32(ip)) ); |
---|
829 | } |
---|
830 | |
---|
831 | /* Catch up */ |
---|
832 | while ((ip>anchor) && (match > lowLimit) && (unlikely(ip[-1]==match[-1]))) { ip--; match--; } |
---|
833 | |
---|
834 | { |
---|
835 | /* Encode Literal length */ |
---|
836 | unsigned litLength = (unsigned)(ip - anchor); |
---|
837 | token = op++; |
---|
838 | if (op + ((litLength+240)/255) + litLength > oMaxLit) |
---|
839 | { |
---|
840 | /* Not enough space for a last match */ |
---|
841 | op--; |
---|
842 | goto _last_literals; |
---|
843 | } |
---|
844 | if (litLength>=RUN_MASK) |
---|
845 | { |
---|
846 | unsigned len = litLength - RUN_MASK; |
---|
847 | *token=(RUN_MASK<<ML_BITS); |
---|
848 | for(; len >= 255 ; len-=255) *op++ = 255; |
---|
849 | *op++ = (BYTE)len; |
---|
850 | } |
---|
851 | else *token = (BYTE)(litLength<<ML_BITS); |
---|
852 | |
---|
853 | /* Copy Literals */ |
---|
854 | LZ4_wildCopy(op, anchor, op+litLength); |
---|
855 | op += litLength; |
---|
856 | } |
---|
857 | |
---|
858 | _next_match: |
---|
859 | /* Encode Offset */ |
---|
860 | LZ4_writeLE16(op, (U16)(ip-match)); op+=2; |
---|
861 | |
---|
862 | /* Encode MatchLength */ |
---|
863 | { |
---|
864 | size_t matchLength; |
---|
865 | |
---|
866 | matchLength = LZ4_count(ip+MINMATCH, match+MINMATCH, matchlimit); |
---|
867 | |
---|
868 | if (op + ((matchLength+240)/255) > oMaxMatch) |
---|
869 | { |
---|
870 | /* Match description too long : reduce it */ |
---|
871 | matchLength = (15-1) + (oMaxMatch-op) * 255; |
---|
872 | } |
---|
873 | ip += MINMATCH + matchLength; |
---|
874 | |
---|
875 | if (matchLength>=ML_MASK) |
---|
876 | { |
---|
877 | *token += ML_MASK; |
---|
878 | matchLength -= ML_MASK; |
---|
879 | while (matchLength >= 255) { matchLength-=255; *op++ = 255; } |
---|
880 | *op++ = (BYTE)matchLength; |
---|
881 | } |
---|
882 | else *token += (BYTE)(matchLength); |
---|
883 | } |
---|
884 | |
---|
885 | anchor = ip; |
---|
886 | |
---|
887 | /* Test end of block */ |
---|
888 | if (ip > mflimit) break; |
---|
889 | if (op > oMaxSeq) break; |
---|
890 | |
---|
891 | /* Fill table */ |
---|
892 | LZ4_putPosition(ip-2, ctx, tableType, base); |
---|
893 | |
---|
894 | /* Test next position */ |
---|
895 | match = LZ4_getPosition(ip, ctx, tableType, base); |
---|
896 | LZ4_putPosition(ip, ctx, tableType, base); |
---|
897 | if ( (match+MAX_DISTANCE>=ip) |
---|
898 | && (LZ4_read32(match)==LZ4_read32(ip)) ) |
---|
899 | { token=op++; *token=0; goto _next_match; } |
---|
900 | |
---|
901 | /* Prepare next loop */ |
---|
902 | forwardH = LZ4_hashPosition(++ip, tableType); |
---|
903 | } |
---|
904 | |
---|
905 | _last_literals: |
---|
906 | /* Encode Last Literals */ |
---|
907 | { |
---|
908 | size_t lastRunSize = (size_t)(iend - anchor); |
---|
909 | if (op + 1 /* token */ + ((lastRunSize+240)/255) /* litLength */ + lastRunSize /* literals */ > oend) |
---|
910 | { |
---|
911 | /* adapt lastRunSize to fill 'dst' */ |
---|
912 | lastRunSize = (oend-op) - 1; |
---|
913 | lastRunSize -= (lastRunSize+240)/255; |
---|
914 | } |
---|
915 | ip = anchor + lastRunSize; |
---|
916 | |
---|
917 | if (lastRunSize >= RUN_MASK) |
---|
918 | { |
---|
919 | size_t accumulator = lastRunSize - RUN_MASK; |
---|
920 | *op++ = RUN_MASK << ML_BITS; |
---|
921 | for(; accumulator >= 255 ; accumulator-=255) *op++ = 255; |
---|
922 | *op++ = (BYTE) accumulator; |
---|
923 | } |
---|
924 | else |
---|
925 | { |
---|
926 | *op++ = (BYTE)(lastRunSize<<ML_BITS); |
---|
927 | } |
---|
928 | memcpy(op, anchor, lastRunSize); |
---|
929 | op += lastRunSize; |
---|
930 | } |
---|
931 | |
---|
932 | /* End */ |
---|
933 | *srcSizePtr = (int) (((const char*)ip)-src); |
---|
934 | return (int) (((char*)op)-dst); |
---|
935 | } |
---|
936 | |
---|
937 | |
---|
938 | static int LZ4_compress_destSize_extState (void* state, const char* src, char* dst, int* srcSizePtr, int targetDstSize) |
---|
939 | { |
---|
940 | LZ4_resetStream((LZ4_stream_t*)state); |
---|
941 | |
---|
942 | if (targetDstSize >= LZ4_compressBound(*srcSizePtr)) /* compression success is guaranteed */ |
---|
943 | { |
---|
944 | return LZ4_compress_fast_extState(state, src, dst, *srcSizePtr, targetDstSize, 1); |
---|
945 | } |
---|
946 | else |
---|
947 | { |
---|
948 | if (*srcSizePtr < LZ4_64Klimit) |
---|
949 | return LZ4_compress_destSize_generic(state, src, dst, srcSizePtr, targetDstSize, byU16); |
---|
950 | else |
---|
951 | return LZ4_compress_destSize_generic(state, src, dst, srcSizePtr, targetDstSize, LZ4_64bits() ? byU32 : byPtr); |
---|
952 | } |
---|
953 | } |
---|
954 | |
---|
955 | |
---|
956 | int LZ4_compress_destSize(const char* src, char* dst, int* srcSizePtr, int targetDstSize) |
---|
957 | { |
---|
958 | #if (HEAPMODE) |
---|
959 | void* ctx = ALLOCATOR(1, sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */ |
---|
960 | #else |
---|
961 | LZ4_stream_t ctxBody; |
---|
962 | void* ctx = &ctxBody; |
---|
963 | #endif |
---|
964 | |
---|
965 | int result = LZ4_compress_destSize_extState(ctx, src, dst, srcSizePtr, targetDstSize); |
---|
966 | |
---|
967 | #if (HEAPMODE) |
---|
968 | FREEMEM(ctx); |
---|
969 | #endif |
---|
970 | return result; |
---|
971 | } |
---|
972 | |
---|
973 | |
---|
974 | |
---|
975 | /******************************** |
---|
976 | * Streaming functions |
---|
977 | ********************************/ |
---|
978 | |
---|
979 | LZ4_stream_t* LZ4_createStream(void) |
---|
980 | { |
---|
981 | LZ4_stream_t* lz4s = (LZ4_stream_t*)ALLOCATOR(8, LZ4_STREAMSIZE_U64); |
---|
982 | LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /* A compilation error here means LZ4_STREAMSIZE is not large enough */ |
---|
983 | LZ4_resetStream(lz4s); |
---|
984 | return lz4s; |
---|
985 | } |
---|
986 | |
---|
987 | void LZ4_resetStream (LZ4_stream_t* LZ4_stream) |
---|
988 | { |
---|
989 | MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t)); |
---|
990 | } |
---|
991 | |
---|
992 | int LZ4_freeStream (LZ4_stream_t* LZ4_stream) |
---|
993 | { |
---|
994 | FREEMEM(LZ4_stream); |
---|
995 | return (0); |
---|
996 | } |
---|
997 | |
---|
998 | |
---|
999 | #define HASH_UNIT sizeof(size_t) |
---|
1000 | int LZ4_loadDict (LZ4_stream_t* LZ4_dict, const char* dictionary, int dictSize) |
---|
1001 | { |
---|
1002 | LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict; |
---|
1003 | const BYTE* p = (const BYTE*)dictionary; |
---|
1004 | const BYTE* const dictEnd = p + dictSize; |
---|
1005 | const BYTE* base; |
---|
1006 | |
---|
1007 | if ((dict->initCheck) || (dict->currentOffset > 1 GB)) /* Uninitialized structure, or reuse overflow */ |
---|
1008 | LZ4_resetStream(LZ4_dict); |
---|
1009 | |
---|
1010 | if (dictSize < (int)HASH_UNIT) |
---|
1011 | { |
---|
1012 | dict->dictionary = NULL; |
---|
1013 | dict->dictSize = 0; |
---|
1014 | return 0; |
---|
1015 | } |
---|
1016 | |
---|
1017 | if ((dictEnd - p) > 64 KB) p = dictEnd - 64 KB; |
---|
1018 | dict->currentOffset += 64 KB; |
---|
1019 | base = p - dict->currentOffset; |
---|
1020 | dict->dictionary = p; |
---|
1021 | dict->dictSize = (U32)(dictEnd - p); |
---|
1022 | dict->currentOffset += dict->dictSize; |
---|
1023 | |
---|
1024 | while (p <= dictEnd-HASH_UNIT) |
---|
1025 | { |
---|
1026 | LZ4_putPosition(p, dict->hashTable, byU32, base); |
---|
1027 | p+=3; |
---|
1028 | } |
---|
1029 | |
---|
1030 | return dict->dictSize; |
---|
1031 | } |
---|
1032 | |
---|
1033 | |
---|
1034 | static void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, const BYTE* src) |
---|
1035 | { |
---|
1036 | if ((LZ4_dict->currentOffset > 0x80000000) || |
---|
1037 | ((size_t)LZ4_dict->currentOffset > (size_t)src)) /* address space overflow */ |
---|
1038 | { |
---|
1039 | /* rescale hash table */ |
---|
1040 | U32 delta = LZ4_dict->currentOffset - 64 KB; |
---|
1041 | const BYTE* dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize; |
---|
1042 | int i; |
---|
1043 | for (i=0; i<HASH_SIZE_U32; i++) |
---|
1044 | { |
---|
1045 | if (LZ4_dict->hashTable[i] < delta) LZ4_dict->hashTable[i]=0; |
---|
1046 | else LZ4_dict->hashTable[i] -= delta; |
---|
1047 | } |
---|
1048 | LZ4_dict->currentOffset = 64 KB; |
---|
1049 | if (LZ4_dict->dictSize > 64 KB) LZ4_dict->dictSize = 64 KB; |
---|
1050 | LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize; |
---|
1051 | } |
---|
1052 | } |
---|
1053 | |
---|
1054 | |
---|
1055 | int LZ4_compress_fast_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize, int acceleration) |
---|
1056 | { |
---|
1057 | LZ4_stream_t_internal* streamPtr = (LZ4_stream_t_internal*)LZ4_stream; |
---|
1058 | const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize; |
---|
1059 | |
---|
1060 | const BYTE* smallest = (const BYTE*) source; |
---|
1061 | if (streamPtr->initCheck) return 0; /* Uninitialized structure detected */ |
---|
1062 | if ((streamPtr->dictSize>0) && (smallest>dictEnd)) smallest = dictEnd; |
---|
1063 | LZ4_renormDictT(streamPtr, smallest); |
---|
1064 | if (acceleration < 1) acceleration = ACCELERATION_DEFAULT; |
---|
1065 | |
---|
1066 | /* Check overlapping input/dictionary space */ |
---|
1067 | { |
---|
1068 | const BYTE* sourceEnd = (const BYTE*) source + inputSize; |
---|
1069 | if ((sourceEnd > streamPtr->dictionary) && (sourceEnd < dictEnd)) |
---|
1070 | { |
---|
1071 | streamPtr->dictSize = (U32)(dictEnd - sourceEnd); |
---|
1072 | if (streamPtr->dictSize > 64 KB) streamPtr->dictSize = 64 KB; |
---|
1073 | if (streamPtr->dictSize < 4) streamPtr->dictSize = 0; |
---|
1074 | streamPtr->dictionary = dictEnd - streamPtr->dictSize; |
---|
1075 | } |
---|
1076 | } |
---|
1077 | |
---|
1078 | /* prefix mode : source data follows dictionary */ |
---|
1079 | if (dictEnd == (const BYTE*)source) |
---|
1080 | { |
---|
1081 | int result; |
---|
1082 | if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) |
---|
1083 | result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, withPrefix64k, dictSmall, acceleration); |
---|
1084 | else |
---|
1085 | result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, withPrefix64k, noDictIssue, acceleration); |
---|
1086 | streamPtr->dictSize += (U32)inputSize; |
---|
1087 | streamPtr->currentOffset += (U32)inputSize; |
---|
1088 | return result; |
---|
1089 | } |
---|
1090 | |
---|
1091 | /* external dictionary mode */ |
---|
1092 | { |
---|
1093 | int result; |
---|
1094 | if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) |
---|
1095 | result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, usingExtDict, dictSmall, acceleration); |
---|
1096 | else |
---|
1097 | result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput, byU32, usingExtDict, noDictIssue, acceleration); |
---|
1098 | streamPtr->dictionary = (const BYTE*)source; |
---|
1099 | streamPtr->dictSize = (U32)inputSize; |
---|
1100 | streamPtr->currentOffset += (U32)inputSize; |
---|
1101 | return result; |
---|
1102 | } |
---|
1103 | } |
---|
1104 | |
---|
1105 | |
---|
1106 | /* Hidden debug function, to force external dictionary mode */ |
---|
1107 | int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int inputSize) |
---|
1108 | { |
---|
1109 | LZ4_stream_t_internal* streamPtr = (LZ4_stream_t_internal*)LZ4_dict; |
---|
1110 | int result; |
---|
1111 | const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize; |
---|
1112 | |
---|
1113 | const BYTE* smallest = dictEnd; |
---|
1114 | if (smallest > (const BYTE*) source) smallest = (const BYTE*) source; |
---|
1115 | LZ4_renormDictT((LZ4_stream_t_internal*)LZ4_dict, smallest); |
---|
1116 | |
---|
1117 | result = LZ4_compress_generic(LZ4_dict, source, dest, inputSize, 0, notLimited, byU32, usingExtDict, noDictIssue, 1); |
---|
1118 | |
---|
1119 | streamPtr->dictionary = (const BYTE*)source; |
---|
1120 | streamPtr->dictSize = (U32)inputSize; |
---|
1121 | streamPtr->currentOffset += (U32)inputSize; |
---|
1122 | |
---|
1123 | return result; |
---|
1124 | } |
---|
1125 | |
---|
1126 | |
---|
1127 | int LZ4_saveDict (LZ4_stream_t* LZ4_dict, char* safeBuffer, int dictSize) |
---|
1128 | { |
---|
1129 | LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict; |
---|
1130 | const BYTE* previousDictEnd = dict->dictionary + dict->dictSize; |
---|
1131 | |
---|
1132 | if ((U32)dictSize > 64 KB) dictSize = 64 KB; /* useless to define a dictionary > 64 KB */ |
---|
1133 | if ((U32)dictSize > dict->dictSize) dictSize = dict->dictSize; |
---|
1134 | |
---|
1135 | memmove(safeBuffer, previousDictEnd - dictSize, dictSize); |
---|
1136 | |
---|
1137 | dict->dictionary = (const BYTE*)safeBuffer; |
---|
1138 | dict->dictSize = (U32)dictSize; |
---|
1139 | |
---|
1140 | return dictSize; |
---|
1141 | } |
---|
1142 | |
---|
1143 | |
---|
1144 | |
---|
1145 | /******************************* |
---|
1146 | * Decompression functions |
---|
1147 | *******************************/ |
---|
1148 | /* |
---|
1149 | * This generic decompression function cover all use cases. |
---|
1150 | * It shall be instantiated several times, using different sets of directives |
---|
1151 | * Note that it is essential this generic function is really inlined, |
---|
1152 | * in order to remove useless branches during compilation optimization. |
---|
1153 | */ |
---|
1154 | FORCE_INLINE int LZ4_decompress_generic( |
---|
1155 | const char* const source, |
---|
1156 | char* const dest, |
---|
1157 | int inputSize, |
---|
1158 | int outputSize, /* If endOnInput==endOnInputSize, this value is the max size of Output Buffer. */ |
---|
1159 | |
---|
1160 | int endOnInput, /* endOnOutputSize, endOnInputSize */ |
---|
1161 | int partialDecoding, /* full, partial */ |
---|
1162 | int targetOutputSize, /* only used if partialDecoding==partial */ |
---|
1163 | int dict, /* noDict, withPrefix64k, usingExtDict */ |
---|
1164 | const BYTE* const lowPrefix, /* == dest if dict == noDict */ |
---|
1165 | const BYTE* const dictStart, /* only if dict==usingExtDict */ |
---|
1166 | const size_t dictSize /* note : = 0 if noDict */ |
---|
1167 | ) |
---|
1168 | { |
---|
1169 | /* Local Variables */ |
---|
1170 | const BYTE* ip = (const BYTE*) source; |
---|
1171 | const BYTE* const iend = ip + inputSize; |
---|
1172 | |
---|
1173 | BYTE* op = (BYTE*) dest; |
---|
1174 | BYTE* const oend = op + outputSize; |
---|
1175 | BYTE* cpy; |
---|
1176 | BYTE* oexit = op + targetOutputSize; |
---|
1177 | const BYTE* const lowLimit = lowPrefix - dictSize; |
---|
1178 | |
---|
1179 | const BYTE* const dictEnd = (const BYTE*)dictStart + dictSize; |
---|
1180 | const unsigned dec32table[] = {4, 1, 2, 1, 4, 4, 4, 4}; |
---|
1181 | const int dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3}; |
---|
1182 | |
---|
1183 | const int safeDecode = (endOnInput==endOnInputSize); |
---|
1184 | const int checkOffset = ((safeDecode) && (dictSize < (int)(64 KB))); |
---|
1185 | |
---|
1186 | |
---|
1187 | /* Special cases */ |
---|
1188 | if ((partialDecoding) && (oexit> oend-MFLIMIT)) oexit = oend-MFLIMIT; /* targetOutputSize too high => decode everything */ |
---|
1189 | if ((endOnInput) && (unlikely(outputSize==0))) return ((inputSize==1) && (*ip==0)) ? 0 : -1; /* Empty output buffer */ |
---|
1190 | if ((!endOnInput) && (unlikely(outputSize==0))) return (*ip==0?1:-1); |
---|
1191 | |
---|
1192 | |
---|
1193 | /* Main Loop */ |
---|
1194 | while (1) |
---|
1195 | { |
---|
1196 | unsigned token; |
---|
1197 | size_t length; |
---|
1198 | const BYTE* match; |
---|
1199 | size_t offset; |
---|
1200 | |
---|
1201 | /* get literal length */ |
---|
1202 | token = *ip++; |
---|
1203 | if ((length=(token>>ML_BITS)) == RUN_MASK) |
---|
1204 | { |
---|
1205 | unsigned s; |
---|
1206 | do |
---|
1207 | { |
---|
1208 | s = *ip++; |
---|
1209 | length += s; |
---|
1210 | } |
---|
1211 | while ( likely(endOnInput ? ip<iend-RUN_MASK : 1) && (s==255) ); |
---|
1212 | if ((safeDecode) && unlikely((size_t)(op+length)<(size_t)(op))) goto _output_error; /* overflow detection */ |
---|
1213 | if ((safeDecode) && unlikely((size_t)(ip+length)<(size_t)(ip))) goto _output_error; /* overflow detection */ |
---|
1214 | } |
---|
1215 | |
---|
1216 | /* copy literals */ |
---|
1217 | cpy = op+length; |
---|
1218 | if (((endOnInput) && ((cpy>(partialDecoding?oexit:oend-MFLIMIT)) || (ip+length>iend-(2+1+LASTLITERALS))) ) |
---|
1219 | || ((!endOnInput) && (cpy>oend-WILDCOPYLENGTH))) |
---|
1220 | { |
---|
1221 | if (partialDecoding) |
---|
1222 | { |
---|
1223 | if (cpy > oend) goto _output_error; /* Error : write attempt beyond end of output buffer */ |
---|
1224 | if ((endOnInput) && (ip+length > iend)) goto _output_error; /* Error : read attempt beyond end of input buffer */ |
---|
1225 | } |
---|
1226 | else |
---|
1227 | { |
---|
1228 | if ((!endOnInput) && (cpy != oend)) goto _output_error; /* Error : block decoding must stop exactly there */ |
---|
1229 | if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) goto _output_error; /* Error : input must be consumed */ |
---|
1230 | } |
---|
1231 | memcpy(op, ip, length); |
---|
1232 | ip += length; |
---|
1233 | op += length; |
---|
1234 | break; /* Necessarily EOF, due to parsing restrictions */ |
---|
1235 | } |
---|
1236 | LZ4_wildCopy(op, ip, cpy); |
---|
1237 | ip += length; op = cpy; |
---|
1238 | |
---|
1239 | /* get offset */ |
---|
1240 | offset = LZ4_readLE16(ip); ip+=2; |
---|
1241 | match = op - offset; |
---|
1242 | if ((checkOffset) && (unlikely(match < lowLimit))) goto _output_error; /* Error : offset outside buffers */ |
---|
1243 | |
---|
1244 | /* get matchlength */ |
---|
1245 | length = token & ML_MASK; |
---|
1246 | if (length == ML_MASK) |
---|
1247 | { |
---|
1248 | unsigned s; |
---|
1249 | do |
---|
1250 | { |
---|
1251 | if ((endOnInput) && (ip > iend-LASTLITERALS)) goto _output_error; |
---|
1252 | s = *ip++; |
---|
1253 | length += s; |
---|
1254 | } while (s==255); |
---|
1255 | if ((safeDecode) && unlikely((size_t)(op+length)<(size_t)op)) goto _output_error; /* overflow detection */ |
---|
1256 | } |
---|
1257 | length += MINMATCH; |
---|
1258 | |
---|
1259 | /* check external dictionary */ |
---|
1260 | if ((dict==usingExtDict) && (match < lowPrefix)) |
---|
1261 | { |
---|
1262 | if (unlikely(op+length > oend-LASTLITERALS)) goto _output_error; /* doesn't respect parsing restriction */ |
---|
1263 | |
---|
1264 | if (length <= (size_t)(lowPrefix-match)) |
---|
1265 | { |
---|
1266 | /* match can be copied as a single segment from external dictionary */ |
---|
1267 | match = dictEnd - (lowPrefix-match); |
---|
1268 | memmove(op, match, length); op += length; |
---|
1269 | } |
---|
1270 | else |
---|
1271 | { |
---|
1272 | /* match encompass external dictionary and current block */ |
---|
1273 | size_t copySize = (size_t)(lowPrefix-match); |
---|
1274 | memcpy(op, dictEnd - copySize, copySize); |
---|
1275 | op += copySize; |
---|
1276 | copySize = length - copySize; |
---|
1277 | if (copySize > (size_t)(op-lowPrefix)) /* overlap copy */ |
---|
1278 | { |
---|
1279 | BYTE* const endOfMatch = op + copySize; |
---|
1280 | const BYTE* copyFrom = lowPrefix; |
---|
1281 | while (op < endOfMatch) *op++ = *copyFrom++; |
---|
1282 | } |
---|
1283 | else |
---|
1284 | { |
---|
1285 | memcpy(op, lowPrefix, copySize); |
---|
1286 | op += copySize; |
---|
1287 | } |
---|
1288 | } |
---|
1289 | continue; |
---|
1290 | } |
---|
1291 | |
---|
1292 | /* copy match within block */ |
---|
1293 | cpy = op + length; |
---|
1294 | if (unlikely(offset<8)) |
---|
1295 | { |
---|
1296 | const int dec64 = dec64table[offset]; |
---|
1297 | op[0] = match[0]; |
---|
1298 | op[1] = match[1]; |
---|
1299 | op[2] = match[2]; |
---|
1300 | op[3] = match[3]; |
---|
1301 | match += dec32table[offset]; |
---|
1302 | memcpy(op+4, match, 4); |
---|
1303 | match -= dec64; |
---|
1304 | } else { LZ4_copy8(op, match); match+=8; } |
---|
1305 | op += 8; |
---|
1306 | |
---|
1307 | if (unlikely(cpy>oend-12)) |
---|
1308 | { |
---|
1309 | BYTE* const oCopyLimit = oend-(WILDCOPYLENGTH-1); |
---|
1310 | if (cpy > oend-LASTLITERALS) goto _output_error; /* Error : last LASTLITERALS bytes must be literals (uncompressed) */ |
---|
1311 | if (op < oCopyLimit) |
---|
1312 | { |
---|
1313 | LZ4_wildCopy(op, match, oCopyLimit); |
---|
1314 | match += oCopyLimit - op; |
---|
1315 | op = oCopyLimit; |
---|
1316 | } |
---|
1317 | while (op<cpy) *op++ = *match++; |
---|
1318 | } |
---|
1319 | else |
---|
1320 | LZ4_wildCopy(op, match, cpy); |
---|
1321 | op=cpy; /* correction */ |
---|
1322 | } |
---|
1323 | |
---|
1324 | /* end of decoding */ |
---|
1325 | if (endOnInput) |
---|
1326 | return (int) (((char*)op)-dest); /* Nb of output bytes decoded */ |
---|
1327 | else |
---|
1328 | return (int) (((const char*)ip)-source); /* Nb of input bytes read */ |
---|
1329 | |
---|
1330 | /* Overflow error detected */ |
---|
1331 | _output_error: |
---|
1332 | return (int) (-(((const char*)ip)-source))-1; |
---|
1333 | } |
---|
1334 | |
---|
1335 | |
---|
1336 | int LZ4_decompress_safe(const char* source, char* dest, int compressedSize, int maxDecompressedSize) |
---|
1337 | { |
---|
1338 | return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize, endOnInputSize, full, 0, noDict, (BYTE*)dest, NULL, 0); |
---|
1339 | } |
---|
1340 | |
---|
1341 | int LZ4_decompress_safe_partial(const char* source, char* dest, int compressedSize, int targetOutputSize, int maxDecompressedSize) |
---|
1342 | { |
---|
1343 | return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize, endOnInputSize, partial, targetOutputSize, noDict, (BYTE*)dest, NULL, 0); |
---|
1344 | } |
---|
1345 | |
---|
1346 | int LZ4_decompress_fast(const char* source, char* dest, int originalSize) |
---|
1347 | { |
---|
1348 | return LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, withPrefix64k, (BYTE*)(dest - 64 KB), NULL, 64 KB); |
---|
1349 | } |
---|
1350 | |
---|
1351 | |
---|
1352 | /* streaming decompression functions */ |
---|
1353 | |
---|
1354 | typedef struct |
---|
1355 | { |
---|
1356 | const BYTE* externalDict; |
---|
1357 | size_t extDictSize; |
---|
1358 | const BYTE* prefixEnd; |
---|
1359 | size_t prefixSize; |
---|
1360 | } LZ4_streamDecode_t_internal; |
---|
1361 | |
---|
1362 | /* |
---|
1363 | * If you prefer dynamic allocation methods, |
---|
1364 | * LZ4_createStreamDecode() |
---|
1365 | * provides a pointer (void*) towards an initialized LZ4_streamDecode_t structure. |
---|
1366 | */ |
---|
1367 | LZ4_streamDecode_t* LZ4_createStreamDecode(void) |
---|
1368 | { |
---|
1369 | LZ4_streamDecode_t* lz4s = (LZ4_streamDecode_t*) ALLOCATOR(1, sizeof(LZ4_streamDecode_t)); |
---|
1370 | return lz4s; |
---|
1371 | } |
---|
1372 | |
---|
1373 | int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream) |
---|
1374 | { |
---|
1375 | FREEMEM(LZ4_stream); |
---|
1376 | return 0; |
---|
1377 | } |
---|
1378 | |
---|
1379 | /* |
---|
1380 | * LZ4_setStreamDecode |
---|
1381 | * Use this function to instruct where to find the dictionary |
---|
1382 | * This function is not necessary if previous data is still available where it was decoded. |
---|
1383 | * Loading a size of 0 is allowed (same effect as no dictionary). |
---|
1384 | * Return : 1 if OK, 0 if error |
---|
1385 | */ |
---|
1386 | int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize) |
---|
1387 | { |
---|
1388 | LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode; |
---|
1389 | lz4sd->prefixSize = (size_t) dictSize; |
---|
1390 | lz4sd->prefixEnd = (const BYTE*) dictionary + dictSize; |
---|
1391 | lz4sd->externalDict = NULL; |
---|
1392 | lz4sd->extDictSize = 0; |
---|
1393 | return 1; |
---|
1394 | } |
---|
1395 | |
---|
1396 | /* |
---|
1397 | *_continue() : |
---|
1398 | These decoding functions allow decompression of multiple blocks in "streaming" mode. |
---|
1399 | Previously decoded blocks must still be available at the memory position where they were decoded. |
---|
1400 | If it's not possible, save the relevant part of decoded data into a safe buffer, |
---|
1401 | and indicate where it stands using LZ4_setStreamDecode() |
---|
1402 | */ |
---|
1403 | int LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxOutputSize) |
---|
1404 | { |
---|
1405 | LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode; |
---|
1406 | int result; |
---|
1407 | |
---|
1408 | if (lz4sd->prefixEnd == (BYTE*)dest) |
---|
1409 | { |
---|
1410 | result = LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, |
---|
1411 | endOnInputSize, full, 0, |
---|
1412 | usingExtDict, lz4sd->prefixEnd - lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize); |
---|
1413 | if (result <= 0) return result; |
---|
1414 | lz4sd->prefixSize += result; |
---|
1415 | lz4sd->prefixEnd += result; |
---|
1416 | } |
---|
1417 | else |
---|
1418 | { |
---|
1419 | lz4sd->extDictSize = lz4sd->prefixSize; |
---|
1420 | lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize; |
---|
1421 | result = LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, |
---|
1422 | endOnInputSize, full, 0, |
---|
1423 | usingExtDict, (BYTE*)dest, lz4sd->externalDict, lz4sd->extDictSize); |
---|
1424 | if (result <= 0) return result; |
---|
1425 | lz4sd->prefixSize = result; |
---|
1426 | lz4sd->prefixEnd = (BYTE*)dest + result; |
---|
1427 | } |
---|
1428 | |
---|
1429 | return result; |
---|
1430 | } |
---|
1431 | |
---|
1432 | int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* source, char* dest, int originalSize) |
---|
1433 | { |
---|
1434 | LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode; |
---|
1435 | int result; |
---|
1436 | |
---|
1437 | if (lz4sd->prefixEnd == (BYTE*)dest) |
---|
1438 | { |
---|
1439 | result = LZ4_decompress_generic(source, dest, 0, originalSize, |
---|
1440 | endOnOutputSize, full, 0, |
---|
1441 | usingExtDict, lz4sd->prefixEnd - lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize); |
---|
1442 | if (result <= 0) return result; |
---|
1443 | lz4sd->prefixSize += originalSize; |
---|
1444 | lz4sd->prefixEnd += originalSize; |
---|
1445 | } |
---|
1446 | else |
---|
1447 | { |
---|
1448 | lz4sd->extDictSize = lz4sd->prefixSize; |
---|
1449 | lz4sd->externalDict = (BYTE*)dest - lz4sd->extDictSize; |
---|
1450 | result = LZ4_decompress_generic(source, dest, 0, originalSize, |
---|
1451 | endOnOutputSize, full, 0, |
---|
1452 | usingExtDict, (BYTE*)dest, lz4sd->externalDict, lz4sd->extDictSize); |
---|
1453 | if (result <= 0) return result; |
---|
1454 | lz4sd->prefixSize = originalSize; |
---|
1455 | lz4sd->prefixEnd = (BYTE*)dest + originalSize; |
---|
1456 | } |
---|
1457 | |
---|
1458 | return result; |
---|
1459 | } |
---|
1460 | |
---|
1461 | |
---|
1462 | /* |
---|
1463 | Advanced decoding functions : |
---|
1464 | *_usingDict() : |
---|
1465 | These decoding functions work the same as "_continue" ones, |
---|
1466 | the dictionary must be explicitly provided within parameters |
---|
1467 | */ |
---|
1468 | |
---|
1469 | FORCE_INLINE int LZ4_decompress_usingDict_generic(const char* source, char* dest, int compressedSize, int maxOutputSize, int safe, const char* dictStart, int dictSize) |
---|
1470 | { |
---|
1471 | if (dictSize==0) |
---|
1472 | return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, safe, full, 0, noDict, (BYTE*)dest, NULL, 0); |
---|
1473 | if (dictStart+dictSize == dest) |
---|
1474 | { |
---|
1475 | if (dictSize >= (int)(64 KB - 1)) |
---|
1476 | return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, safe, full, 0, withPrefix64k, (BYTE*)dest-64 KB, NULL, 0); |
---|
1477 | return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, safe, full, 0, noDict, (BYTE*)dest-dictSize, NULL, 0); |
---|
1478 | } |
---|
1479 | return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, safe, full, 0, usingExtDict, (BYTE*)dest, (const BYTE*)dictStart, dictSize); |
---|
1480 | } |
---|
1481 | |
---|
1482 | int LZ4_decompress_safe_usingDict(const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize) |
---|
1483 | { |
---|
1484 | return LZ4_decompress_usingDict_generic(source, dest, compressedSize, maxOutputSize, 1, dictStart, dictSize); |
---|
1485 | } |
---|
1486 | |
---|
1487 | int LZ4_decompress_fast_usingDict(const char* source, char* dest, int originalSize, const char* dictStart, int dictSize) |
---|
1488 | { |
---|
1489 | return LZ4_decompress_usingDict_generic(source, dest, 0, originalSize, 0, dictStart, dictSize); |
---|
1490 | } |
---|
1491 | |
---|
1492 | /* debug function */ |
---|
1493 | int LZ4_decompress_safe_forceExtDict(const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize) |
---|
1494 | { |
---|
1495 | return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, usingExtDict, (BYTE*)dest, (const BYTE*)dictStart, dictSize); |
---|
1496 | } |
---|
1497 | |
---|
1498 | |
---|
1499 | /*************************************************** |
---|
1500 | * Obsolete Functions |
---|
1501 | ***************************************************/ |
---|
1502 | /* obsolete compression functions */ |
---|
1503 | int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize) { return LZ4_compress_default(source, dest, inputSize, maxOutputSize); } |
---|
1504 | int LZ4_compress(const char* source, char* dest, int inputSize) { return LZ4_compress_default(source, dest, inputSize, LZ4_compressBound(inputSize)); } |
---|
1505 | 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); } |
---|
1506 | 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); } |
---|
1507 | int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_stream, const char* src, char* dst, int srcSize, int maxDstSize) { return LZ4_compress_fast_continue(LZ4_stream, src, dst, srcSize, maxDstSize, 1); } |
---|
1508 | 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); } |
---|
1509 | |
---|
1510 | /* |
---|
1511 | These function names are deprecated and should no longer be used. |
---|
1512 | They are only provided here for compatibility with older user programs. |
---|
1513 | - LZ4_uncompress is totally equivalent to LZ4_decompress_fast |
---|
1514 | - LZ4_uncompress_unknownOutputSize is totally equivalent to LZ4_decompress_safe |
---|
1515 | */ |
---|
1516 | int LZ4_uncompress (const char* source, char* dest, int outputSize) { return LZ4_decompress_fast(source, dest, outputSize); } |
---|
1517 | int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize) { return LZ4_decompress_safe(source, dest, isize, maxOutputSize); } |
---|
1518 | |
---|
1519 | |
---|
1520 | /* Obsolete Streaming functions */ |
---|
1521 | |
---|
1522 | int LZ4_sizeofStreamState() { return LZ4_STREAMSIZE; } |
---|
1523 | |
---|
1524 | static void LZ4_init(LZ4_stream_t_internal* lz4ds, BYTE* base) |
---|
1525 | { |
---|
1526 | MEM_INIT(lz4ds, 0, LZ4_STREAMSIZE); |
---|
1527 | lz4ds->bufferStart = base; |
---|
1528 | } |
---|
1529 | |
---|
1530 | int LZ4_resetStreamState(void* state, char* inputBuffer) |
---|
1531 | { |
---|
1532 | if ((((size_t)state) & 3) != 0) return 1; /* Error : pointer is not aligned on 4-bytes boundary */ |
---|
1533 | LZ4_init((LZ4_stream_t_internal*)state, (BYTE*)inputBuffer); |
---|
1534 | return 0; |
---|
1535 | } |
---|
1536 | |
---|
1537 | void* LZ4_create (char* inputBuffer) |
---|
1538 | { |
---|
1539 | void* lz4ds = ALLOCATOR(8, LZ4_STREAMSIZE_U64); |
---|
1540 | LZ4_init ((LZ4_stream_t_internal*)lz4ds, (BYTE*)inputBuffer); |
---|
1541 | return lz4ds; |
---|
1542 | } |
---|
1543 | |
---|
1544 | char* LZ4_slideInputBuffer (void* LZ4_Data) |
---|
1545 | { |
---|
1546 | LZ4_stream_t_internal* ctx = (LZ4_stream_t_internal*)LZ4_Data; |
---|
1547 | int dictSize = LZ4_saveDict((LZ4_stream_t*)LZ4_Data, (char*)ctx->bufferStart, 64 KB); |
---|
1548 | return (char*)(ctx->bufferStart + dictSize); |
---|
1549 | } |
---|
1550 | |
---|
1551 | /* Obsolete streaming decompression functions */ |
---|
1552 | |
---|
1553 | int LZ4_decompress_safe_withPrefix64k(const char* source, char* dest, int compressedSize, int maxOutputSize) |
---|
1554 | { |
---|
1555 | return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, withPrefix64k, (BYTE*)dest - 64 KB, NULL, 64 KB); |
---|
1556 | } |
---|
1557 | |
---|
1558 | int LZ4_decompress_fast_withPrefix64k(const char* source, char* dest, int originalSize) |
---|
1559 | { |
---|
1560 | return LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, withPrefix64k, (BYTE*)dest - 64 KB, NULL, 64 KB); |
---|
1561 | } |
---|
1562 | |
---|
1563 | #endif /* LZ4_COMMONDEFS_ONLY */ |
---|
1564 | |
---|