| /* LzmaLib.h -- LZMA library interface |
| 2013-01-18 : Igor Pavlov : Public domain */ |
| |
| #ifndef __LZMA_LIB_H |
| #define __LZMA_LIB_H |
| |
| #include "7zTypes.h" |
| |
| EXTERN_C_BEGIN |
| |
| #define MY_STDAPI int MY_STD_CALL |
| |
| #define LZMA_PROPS_SIZE 5 |
| |
| /* |
| RAM requirements for LZMA: |
| for compression: (dictSize * 11.5 + 6 MB) + state_size |
| for decompression: dictSize + state_size |
| state_size = (4 + (1.5 << (lc + lp))) KB |
| by default (lc=3, lp=0), state_size = 16 KB. |
| |
| LZMA properties (5 bytes) format |
| Offset Size Description |
| 0 1 lc, lp and pb in encoded form. |
| 1 4 dictSize (little endian). |
| */ |
| |
| /* |
| LzmaCompress |
| ------------ |
| |
| outPropsSize - |
| In: the pointer to the size of outProps buffer; *outPropsSize = LZMA_PROPS_SIZE = 5. |
| Out: the pointer to the size of written properties in outProps buffer; *outPropsSize = LZMA_PROPS_SIZE = 5. |
| |
| LZMA Encoder will use defult values for any parameter, if it is |
| -1 for any from: level, loc, lp, pb, fb, numThreads |
| 0 for dictSize |
| |
| level - compression level: 0 <= level <= 9; |
| |
| level dictSize algo fb |
| 0: 16 KB 0 32 |
| 1: 64 KB 0 32 |
| 2: 256 KB 0 32 |
| 3: 1 MB 0 32 |
| 4: 4 MB 0 32 |
| 5: 16 MB 1 32 |
| 6: 32 MB 1 32 |
| 7+: 64 MB 1 64 |
| |
| The default value for "level" is 5. |
| |
| algo = 0 means fast method |
| algo = 1 means normal method |
| |
| dictSize - The dictionary size in bytes. The maximum value is |
| 128 MB = (1 << 27) bytes for 32-bit version |
| 1 GB = (1 << 30) bytes for 64-bit version |
| The default value is 16 MB = (1 << 24) bytes. |
| It's recommended to use the dictionary that is larger than 4 KB and |
| that can be calculated as (1 << N) or (3 << N) sizes. |
| |
| lc - The number of literal context bits (high bits of previous literal). |
| It can be in the range from 0 to 8. The default value is 3. |
| Sometimes lc=4 gives the gain for big files. |
| |
| lp - The number of literal pos bits (low bits of current position for literals). |
| It can be in the range from 0 to 4. The default value is 0. |
| The lp switch is intended for periodical data when the period is equal to 2^lp. |
| For example, for 32-bit (4 bytes) periodical data you can use lp=2. Often it's |
| better to set lc=0, if you change lp switch. |
| |
| pb - The number of pos bits (low bits of current position). |
| It can be in the range from 0 to 4. The default value is 2. |
| The pb switch is intended for periodical data when the period is equal 2^pb. |
| |
| fb - Word size (the number of fast bytes). |
| It can be in the range from 5 to 273. The default value is 32. |
| Usually, a big number gives a little bit better compression ratio and |
| slower compression process. |
| |
| numThreads - The number of thereads. 1 or 2. The default value is 2. |
| Fast mode (algo = 0) can use only 1 thread. |
| |
| Out: |
| destLen - processed output size |
| Returns: |
| SZ_OK - OK |
| SZ_ERROR_MEM - Memory allocation error |
| SZ_ERROR_PARAM - Incorrect paramater |
| SZ_ERROR_OUTPUT_EOF - output buffer overflow |
| SZ_ERROR_THREAD - errors in multithreading functions (only for Mt version) |
| */ |
| |
| MY_STDAPI LzmaCompress(unsigned char *dest, size_t *destLen, const unsigned char *src, size_t srcLen, |
| unsigned char *outProps, size_t *outPropsSize, /* *outPropsSize must be = 5 */ |
| int level, /* 0 <= level <= 9, default = 5 */ |
| unsigned dictSize, /* default = (1 << 24) */ |
| int lc, /* 0 <= lc <= 8, default = 3 */ |
| int lp, /* 0 <= lp <= 4, default = 0 */ |
| int pb, /* 0 <= pb <= 4, default = 2 */ |
| int fb, /* 5 <= fb <= 273, default = 32 */ |
| int numThreads /* 1 or 2, default = 2 */ |
| ); |
| |
| /* |
| LzmaUncompress |
| -------------- |
| In: |
| dest - output data |
| destLen - output data size |
| src - input data |
| srcLen - input data size |
| Out: |
| destLen - processed output size |
| srcLen - processed input size |
| Returns: |
| SZ_OK - OK |
| SZ_ERROR_DATA - Data error |
| SZ_ERROR_MEM - Memory allocation arror |
| SZ_ERROR_UNSUPPORTED - Unsupported properties |
| SZ_ERROR_INPUT_EOF - it needs more bytes in input buffer (src) |
| */ |
| |
| MY_STDAPI LzmaUncompress(unsigned char *dest, size_t *destLen, const unsigned char *src, SizeT *srcLen, |
| const unsigned char *props, size_t propsSize); |
| |
| EXTERN_C_END |
| |
| #endif |