diff options
| -rw-r--r-- | doc/lz4_manual.html | 21 | ||||
| -rw-r--r-- | lib/lz4.h | 23 |
2 files changed, 23 insertions, 21 deletions
diff --git a/doc/lz4_manual.html b/doc/lz4_manual.html index b5a4042..43107c6 100644 --- a/doc/lz4_manual.html +++ b/doc/lz4_manual.html @@ -172,28 +172,29 @@ int LZ4_freeStream (LZ4_stream_t* streamPtr); </p></pre><BR> <pre><b>int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration); -</b><p> Compress content into 'src' using data from previously compressed blocks, improving compression ratio. +</b><p> Compress 'src' content using data from previously compressed blocks, for better compression ratio. 'dst' buffer must be already allocated. If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster. - Important : The previous 64KB of compressed data is assumed to remain preset and unmodified in memory! - If less than 64KB has been compressed all the data must be present. + Important : The previous 64KB of compressed data is assumed to remain present and unmodified in memory! + Special 1 : When input is a double-buffer, they can have any size, including < 64 KB. Make sure that buffers are separated by at least one byte. - This way, rule becomes simple : each block depends on previous block only. + This way, each block only depends on previous block. Special 2 : If input buffer is a ring-buffer, it can have any size, including < 64 KB. @return : size of compressed block - or 0 if there is an error (typically, compressed data cannot fit into 'dst') + or 0 if there is an error (typically, cannot fit into 'dst'). After an error, the stream status is invalid, it can only be reset or freed. </p></pre><BR> -<pre><b>int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int dictSize); -</b><p> If previously compressed data block is not guaranteed to remain available at its current memory location, +<pre><b>int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int maxDictSize); +</b><p> If last 64KB data cannot be guaranteed to remain available at its current memory location, save it into a safer place (char* safeBuffer). - Note : it's not necessary to call LZ4_loadDict() after LZ4_saveDict(), dictionary is immediately usable. - @return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error. + This is schematically equivalent to a memcpy() followed by LZ4_loadDict(), + but is much faster, because LZ4_saveDict() doesn't need to rebuild tables. + @return : saved dictionary size in bytes (necessarily <= maxDictSize), or 0 if error. </p></pre><BR> @@ -209,7 +210,7 @@ int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream); <pre><b>int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize); </b><p> An LZ4_streamDecode_t structure can be allocated once and re-used multiple times. Use this function to start decompression of a new stream of blocks. - A dictionary can optionnally be set. Use NULL or size 0 for a simple reset order. + A dictionary can optionnally be set. Use NULL or size 0 for a reset order. @return : 1 if OK, 0 if error </p></pre><BR> @@ -236,7 +236,7 @@ LZ4LIB_API int LZ4_decompress_safe_partial (const char* src, char* dst, int srcS /*-********************************************* * Streaming Compression Functions ***********************************************/ -typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */ +typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */ /*! LZ4_createStream() and LZ4_freeStream() : * LZ4_createStream() will allocate and initialize an `LZ4_stream_t` structure. @@ -260,30 +260,31 @@ LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr); LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize); /*! LZ4_compress_fast_continue() : - * Compress content into 'src' using data from previously compressed blocks, improving compression ratio. + * Compress 'src' content using data from previously compressed blocks, for better compression ratio. * 'dst' buffer must be already allocated. * If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster. * - * Important : The previous 64KB of compressed data is assumed to remain preset and unmodified in memory! - * If less than 64KB has been compressed all the data must be present. + * Important : The previous 64KB of compressed data is assumed to remain present and unmodified in memory! + * * Special 1 : When input is a double-buffer, they can have any size, including < 64 KB. * Make sure that buffers are separated by at least one byte. - * This way, rule becomes simple : each block depends on previous block only. + * This way, each block only depends on previous block. * Special 2 : If input buffer is a ring-buffer, it can have any size, including < 64 KB. * * @return : size of compressed block - * or 0 if there is an error (typically, compressed data cannot fit into 'dst') + * or 0 if there is an error (typically, cannot fit into 'dst'). * After an error, the stream status is invalid, it can only be reset or freed. */ LZ4LIB_API int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration); /*! LZ4_saveDict() : - * If previously compressed data block is not guaranteed to remain available at its current memory location, + * If last 64KB data cannot be guaranteed to remain available at its current memory location, * save it into a safer place (char* safeBuffer). - * Note : it's not necessary to call LZ4_loadDict() after LZ4_saveDict(), dictionary is immediately usable. - * @return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error. + * This is schematically equivalent to a memcpy() followed by LZ4_loadDict(), + * but is much faster, because LZ4_saveDict() doesn't need to rebuild tables. + * @return : saved dictionary size in bytes (necessarily <= maxDictSize), or 0 if error. */ -LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int dictSize); +LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int maxDictSize); /*-********************************************** @@ -301,7 +302,7 @@ LZ4LIB_API int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_str /*! LZ4_setStreamDecode() : * An LZ4_streamDecode_t structure can be allocated once and re-used multiple times. * Use this function to start decompression of a new stream of blocks. - * A dictionary can optionnally be set. Use NULL or size 0 for a simple reset order. + * A dictionary can optionnally be set. Use NULL or size 0 for a reset order. * @return : 1 if OK, 0 if error */ LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize); |