1/* LzmaLib.h -- LZMA library interface 22023-04-02 : Igor Pavlov : Public domain */ 3 4#ifndef ZIP7_INC_LZMA_LIB_H 5#define ZIP7_INC_LZMA_LIB_H 6 7#include "7zTypes.h" 8 9EXTERN_C_BEGIN 10 11#define Z7_STDAPI int Z7_STDCALL 12 13#define LZMA_PROPS_SIZE 5 14 15/* 16RAM requirements for LZMA: 17 for compression: (dictSize * 11.5 + 6 MB) + state_size 18 for decompression: dictSize + state_size 19 state_size = (4 + (1.5 << (lc + lp))) KB 20 by default (lc=3, lp=0), state_size = 16 KB. 21 22LZMA properties (5 bytes) format 23 Offset Size Description 24 0 1 lc, lp and pb in encoded form. 25 1 4 dictSize (little endian). 26*/ 27 28/* 29LzmaCompress 30------------ 31 32outPropsSize - 33 In: the pointer to the size of outProps buffer; *outPropsSize = LZMA_PROPS_SIZE = 5. 34 Out: the pointer to the size of written properties in outProps buffer; *outPropsSize = LZMA_PROPS_SIZE = 5. 35 36 LZMA Encoder will use defult values for any parameter, if it is 37 -1 for any from: level, loc, lp, pb, fb, numThreads 38 0 for dictSize 39 40level - compression level: 0 <= level <= 9; 41 42 level dictSize algo fb 43 0: 64 KB 0 32 44 1: 256 KB 0 32 45 2: 1 MB 0 32 46 3: 4 MB 0 32 47 4: 16 MB 0 32 48 5: 16 MB 1 32 49 6: 32 MB 1 32 50 7: 32 MB 1 64 51 8: 64 MB 1 64 52 9: 64 MB 1 64 53 54 The default value for "level" is 5. 55 56 algo = 0 means fast method 57 algo = 1 means normal method 58 59dictSize - The dictionary size in bytes. The maximum value is 60 128 MB = (1 << 27) bytes for 32-bit version 61 1 GB = (1 << 30) bytes for 64-bit version 62 The default value is 16 MB = (1 << 24) bytes. 63 It's recommended to use the dictionary that is larger than 4 KB and 64 that can be calculated as (1 << N) or (3 << N) sizes. 65 66lc - The number of literal context bits (high bits of previous literal). 67 It can be in the range from 0 to 8. The default value is 3. 68 Sometimes lc=4 gives the gain for big files. 69 70lp - The number of literal pos bits (low bits of current position for literals). 71 It can be in the range from 0 to 4. The default value is 0. 72 The lp switch is intended for periodical data when the period is equal to 2^lp. 73 For example, for 32-bit (4 bytes) periodical data you can use lp=2. Often it's 74 better to set lc=0, if you change lp switch. 75 76pb - The number of pos bits (low bits of current position). 77 It can be in the range from 0 to 4. The default value is 2. 78 The pb switch is intended for periodical data when the period is equal 2^pb. 79 80fb - Word size (the number of fast bytes). 81 It can be in the range from 5 to 273. The default value is 32. 82 Usually, a big number gives a little bit better compression ratio and 83 slower compression process. 84 85numThreads - The number of thereads. 1 or 2. The default value is 2. 86 Fast mode (algo = 0) can use only 1 thread. 87 88In: 89 dest - output data buffer 90 destLen - output data buffer size 91 src - input data 92 srcLen - input data size 93Out: 94 destLen - processed output size 95Returns: 96 SZ_OK - OK 97 SZ_ERROR_MEM - Memory allocation error 98 SZ_ERROR_PARAM - Incorrect paramater 99 SZ_ERROR_OUTPUT_EOF - output buffer overflow 100 SZ_ERROR_THREAD - errors in multithreading functions (only for Mt version) 101*/ 102 103Z7_STDAPI LzmaCompress(unsigned char *dest, size_t *destLen, const unsigned char *src, size_t srcLen, 104 unsigned char *outProps, size_t *outPropsSize, /* *outPropsSize must be = 5 */ 105 int level, /* 0 <= level <= 9, default = 5 */ 106 unsigned dictSize, /* default = (1 << 24) */ 107 int lc, /* 0 <= lc <= 8, default = 3 */ 108 int lp, /* 0 <= lp <= 4, default = 0 */ 109 int pb, /* 0 <= pb <= 4, default = 2 */ 110 int fb, /* 5 <= fb <= 273, default = 32 */ 111 int numThreads /* 1 or 2, default = 2 */ 112 ); 113 114/* 115LzmaUncompress 116-------------- 117In: 118 dest - output data buffer 119 destLen - output data buffer size 120 src - input data 121 srcLen - input data size 122Out: 123 destLen - processed output size 124 srcLen - processed input size 125Returns: 126 SZ_OK - OK 127 SZ_ERROR_DATA - Data error 128 SZ_ERROR_MEM - Memory allocation arror 129 SZ_ERROR_UNSUPPORTED - Unsupported properties 130 SZ_ERROR_INPUT_EOF - it needs more bytes in input buffer (src) 131*/ 132 133Z7_STDAPI LzmaUncompress(unsigned char *dest, size_t *destLen, const unsigned char *src, SizeT *srcLen, 134 const unsigned char *props, size_t propsSize); 135 136EXTERN_C_END 137 138#endif 139