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authorYann Collet <yann.collet.73@gmail.com>2015-05-07 11:23:39 (GMT)
committerYann Collet <yann.collet.73@gmail.com>2015-05-07 11:23:39 (GMT)
commit7d182b816ace89d6d6d16b7aee376a9962a05caa (patch)
tree5b2236b59cd0e42e3365b0765041a25c85519b39 /lib/lz4hc.h
parent160661c7a4cbf805f4af74d2e3932a17a66e6ce7 (diff)
parentfdd0029c3778768d0e8a80ce238d981f946c8b78 (diff)
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Merge pull request #102 from Cyan4973/devrc129v0r129
Dev
Diffstat (limited to 'lib/lz4hc.h')
-rw-r--r--lib/lz4hc.h197
1 files changed, 103 insertions, 94 deletions
diff --git a/lib/lz4hc.h b/lib/lz4hc.h
index 4a05845..431f7c8 100644
--- a/lib/lz4hc.h
+++ b/lib/lz4hc.h
@@ -38,141 +38,150 @@
extern "C" {
#endif
+/*****************************
+* Includes
+*****************************/
+#include <stddef.h> /* size_t */
-int LZ4_compressHC (const char* source, char* dest, int inputSize);
-/*
-LZ4_compressHC :
- return : the number of bytes in compressed buffer dest
- or 0 if compression fails.
- note : destination buffer must be already allocated.
- To avoid any problem, size it to handle worst cases situations (input data not compressible)
- Worst case size evaluation is provided by function LZ4_compressBound() (see "lz4.h")
-*/
-int LZ4_compressHC_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize);
+/**************************************
+* Block Compression
+**************************************/
+int LZ4_compress_HC (const char* src, char* dst, int srcSize, int maxDstSize, int compressionLevel);
/*
-LZ4_compress_limitedOutput() :
- Compress 'inputSize' bytes from 'source' into an output buffer 'dest' of maximum size 'maxOutputSize'.
- If it cannot achieve it, compression will stop, and result of the function will be zero.
- This function never writes outside of provided output buffer.
-
- inputSize : Max supported value is 1 GB
- maxOutputSize : is maximum allowed size into the destination buffer (which must be already allocated)
- return : the number of output bytes written in buffer 'dest'
- or 0 if compression fails.
+LZ4_compress_HC :
+ Destination buffer 'dst' must be already allocated.
+ Compression completion is guaranteed if 'dst' buffer is sized to handle worst circumstances (data not compressible)
+ Worst size evaluation is provided by function LZ4_compressBound() (see "lz4.h")
+ srcSize : Max supported value is LZ4_MAX_INPUT_SIZE (see "lz4.h")
+ compressionLevel : Recommended values are between 4 and 9, although any value between 0 and 16 will work.
+ 0 means "use default value" (see lz4hc.c).
+ Values >16 behave the same as 16.
+ return : the number of bytes written into buffer 'dst'
+ or 0 if compression fails.
*/
-int LZ4_compressHC2 (const char* source, char* dest, int inputSize, int compressionLevel);
-int LZ4_compressHC2_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
-/*
- Same functions as above, but with programmable 'compressionLevel'.
- Recommended values are between 4 and 9, although any value between 0 and 16 will work.
- 'compressionLevel'==0 means use default 'compressionLevel' value.
- Values above 16 behave the same as 16.
- Equivalent variants exist for all other compression functions below.
-*/
-
/* Note :
Decompression functions are provided within LZ4 source code (see "lz4.h") (BSD license)
*/
-/**************************************
-* Using an external allocation
-**************************************/
int LZ4_sizeofStateHC(void);
-int LZ4_compressHC_withStateHC (void* state, const char* source, char* dest, int inputSize);
-int LZ4_compressHC_limitedOutput_withStateHC (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
-
-int LZ4_compressHC2_withStateHC (void* state, const char* source, char* dest, int inputSize, int compressionLevel);
-int LZ4_compressHC2_limitedOutput_withStateHC(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
-
+int LZ4_compress_HC_extStateHC(void* state, const char* src, char* dst, int srcSize, int maxDstSize, int compressionLevel);
/*
-These functions are provided should you prefer to allocate memory for compression tables with your own allocation methods.
-To know how much memory must be allocated for the compression tables, use :
-int LZ4_sizeofStateHC();
+LZ4_compress_HC_extStateHC() :
+ Use this function if you prefer to manually allocate memory for compression tables.
+ To know how much memory must be allocated for the compression tables, use :
+ int LZ4_sizeofStateHC();
-Note that tables must be aligned for pointer (32 or 64 bits), otherwise compression will fail (return code 0).
+ Allocated memory must be aligned on 8-bytes boundaries (which a normal malloc() will do properly).
-The allocated memory can be provided to the compression functions using 'void* state' parameter.
-LZ4_compress_withStateHC() and LZ4_compress_limitedOutput_withStateHC() are equivalent to previously described functions.
-They just use the externally allocated memory for state instead of allocating their own (on stack, or on heap).
+ The allocated memory can then be provided to the compression functions using 'void* state' parameter.
+ LZ4_compress_HC_extStateHC() is equivalent to previously described function.
+ It just uses externally allocated memory for stateHC.
*/
-
-/*****************************
-* Includes
-*****************************/
-#include <stddef.h> /* size_t */
-
-
/**************************************
-* Experimental Streaming Functions
+* Streaming Compression
**************************************/
#define LZ4_STREAMHCSIZE 262192
#define LZ4_STREAMHCSIZE_SIZET (LZ4_STREAMHCSIZE / sizeof(size_t))
typedef struct { size_t table[LZ4_STREAMHCSIZE_SIZET]; } LZ4_streamHC_t;
/*
-LZ4_streamHC_t
-This structure allows static allocation of LZ4 HC streaming state.
-State must then be initialized using LZ4_resetStreamHC() before first use.
+ LZ4_streamHC_t
+ This structure allows static allocation of LZ4 HC streaming state.
+ State must then be initialized using LZ4_resetStreamHC() before first use.
-Static allocation should only be used with statically linked library.
-If you want to use LZ4 as a DLL, please use construction functions below, which are more future-proof.
+ Static allocation should only be used in combination with static linking.
+ If you want to use LZ4 as a DLL, please use construction functions below, which are future-proof.
*/
LZ4_streamHC_t* LZ4_createStreamHC(void);
-int LZ4_freeStreamHC (LZ4_streamHC_t* LZ4_streamHCPtr);
+int LZ4_freeStreamHC (LZ4_streamHC_t* streamHCPtr);
/*
-These functions create and release memory for LZ4 HC streaming state.
-Newly created states are already initialized.
-Existing state space can be re-used anytime using LZ4_resetStreamHC().
-If you use LZ4 as a DLL, please use these functions instead of direct struct allocation,
-to avoid size mismatch between different versions.
+ These functions create and release memory for LZ4 HC streaming state.
+ Newly created states are already initialized.
+ Existing state space can be re-used anytime using LZ4_resetStreamHC().
+ If you use LZ4 as a DLL, use these functions instead of static structure allocation,
+ to avoid size mismatch between different versions.
*/
-void LZ4_resetStreamHC (LZ4_streamHC_t* LZ4_streamHCPtr, int compressionLevel);
-int LZ4_loadDictHC (LZ4_streamHC_t* LZ4_streamHCPtr, const char* dictionary, int dictSize);
+void LZ4_resetStreamHC (LZ4_streamHC_t* streamHCPtr, int compressionLevel);
+int LZ4_loadDictHC (LZ4_streamHC_t* streamHCPtr, const char* dictionary, int dictSize);
-int LZ4_compressHC_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* source, char* dest, int inputSize);
-int LZ4_compressHC_limitedOutput_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
+int LZ4_compress_HC_continue (LZ4_streamHC_t* streamHCPtr, const char* src, char* dst, int srcSize, int maxDstSize);
-int LZ4_saveDictHC (LZ4_streamHC_t* LZ4_streamHCPtr, char* safeBuffer, int maxDictSize);
+int LZ4_saveDictHC (LZ4_streamHC_t* streamHCPtr, char* safeBuffer, int maxDictSize);
/*
-These functions compress data in successive blocks of any size, using previous blocks as dictionary.
-One key assumption is that each previous block will remain read-accessible while compressing next block.
-
-Before starting compression, state must be properly initialized, using LZ4_resetStreamHC().
-A first "fictional block" can then be designated as initial dictionary, using LZ4_loadDictHC() (Optional).
-
-Then, use LZ4_compressHC_continue() or LZ4_compressHC_limitedOutput_continue() to compress each successive block.
-They work like usual LZ4_compressHC() or LZ4_compressHC_limitedOutput(), but use previous memory blocks to improve compression.
-Previous memory blocks (including initial dictionary when present) must remain accessible and unmodified during compression.
-
-If, for any reason, previous data block can't be preserved in memory during next compression block,
-you must save it to a safer memory space,
-using LZ4_saveDictHC().
+ These functions compress data in successive blocks of any size, using previous blocks as dictionary.
+ One key assumption is that previous blocks (up to 64 KB) remain read-accessible while compressing next blocks.
+ There is an exception for ring buffers, which can be smaller 64 KB.
+ Such case is automatically detected and correctly handled by LZ4_compress_HC_continue().
+
+ Before starting compression, state must be properly initialized, using LZ4_resetStreamHC().
+ A first "fictional block" can then be designated as initial dictionary, using LZ4_loadDictHC() (Optional).
+
+ Then, use LZ4_compress_HC_continue() to compress each successive block.
+ It works like LZ4_compress_HC(), but use previous memory blocks as dictionary to improve compression.
+ Previous memory blocks (including initial dictionary when present) must remain accessible and unmodified during compression.
+ As a reminder, size 'dst' buffer to handle worst cases, using LZ4_compressBound(), to ensure success of compression operation.
+
+ If, for any reason, previous data blocks can't be preserved unmodified in memory during next compression block,
+ you must save it to a safer memory space, using LZ4_saveDictHC().
+ Return value of LZ4_saveDictHC() is the size of dictionary effectively saved into 'safeBuffer'.
*/
/**************************************
- * Deprecated Streaming Functions
- * ************************************/
-/* Note : these streaming functions follows the older model, and should no longer be used */
-void* LZ4_createHC (const char* inputBuffer);
-char* LZ4_slideInputBufferHC (void* LZ4HC_Data);
-int LZ4_freeHC (void* LZ4HC_Data);
-
-int LZ4_compressHC2_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int compressionLevel);
-int LZ4_compressHC2_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
-
-int LZ4_sizeofStreamStateHC(void);
-int LZ4_resetStreamStateHC(void* state, const char* inputBuffer);
+* Deprecated Functions
+**************************************/
+/* Deprecate Warnings */
+/* Should these warnings messages be a problem,
+ it is generally possible to disable them,
+ with -Wno-deprecated-declarations for gcc
+ or _CRT_SECURE_NO_WARNINGS in Visual for example.
+ You can also define LZ4_DEPRECATE_WARNING_DEFBLOCK. */
+#ifndef LZ4_DEPRECATE_WARNING_DEFBLOCK
+# define LZ4_DEPRECATE_WARNING_DEFBLOCK
+# define LZ4_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+# if (LZ4_GCC_VERSION >= 405) || defined(__clang__)
+# define LZ4_DEPRECATED(message) __attribute__((deprecated(message)))
+# elif (LZ4_GCC_VERSION >= 301)
+# define LZ4_DEPRECATED(message) __attribute__((deprecated))
+# elif defined(_MSC_VER)
+# define LZ4_DEPRECATED(message) __declspec(deprecated(message))
+# else
+# pragma message("WARNING: You need to implement LZ4_DEPRECATED for this compiler")
+# define LZ4_DEPRECATED(message)
+# endif
+#endif // LZ4_DEPRECATE_WARNING_DEFBLOCK
+
+/* compression functions */
+/* these functions are planned to trigger warning messages by r131 approximately */
+int LZ4_compressHC (const char* source, char* dest, int inputSize);
+int LZ4_compressHC_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize);
+int LZ4_compressHC2 (const char* source, char* dest, int inputSize, int compressionLevel);
+int LZ4_compressHC2_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
+int LZ4_compressHC_withStateHC (void* state, const char* source, char* dest, int inputSize);
+int LZ4_compressHC_limitedOutput_withStateHC (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
+int LZ4_compressHC2_withStateHC (void* state, const char* source, char* dest, int inputSize, int compressionLevel);
+int LZ4_compressHC2_limitedOutput_withStateHC(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
+int LZ4_compressHC_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* source, char* dest, int inputSize);
+int LZ4_compressHC_limitedOutput_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
+
+/* Streaming functions following the older model; should no longer be used */
+LZ4_DEPRECATED("use LZ4_createStreamHC() instead") void* LZ4_createHC (char* inputBuffer);
+LZ4_DEPRECATED("use LZ4_saveDictHC() instead") char* LZ4_slideInputBufferHC (void* LZ4HC_Data);
+LZ4_DEPRECATED("use LZ4_freeStreamHC() instead") int LZ4_freeHC (void* LZ4HC_Data);
+LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") int LZ4_compressHC2_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int compressionLevel);
+LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") int LZ4_compressHC2_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
+LZ4_DEPRECATED("use LZ4_createStreamHC() instead") int LZ4_sizeofStreamStateHC(void);
+LZ4_DEPRECATED("use LZ4_resetStreamHC() instead") int LZ4_resetStreamStateHC(void* state, char* inputBuffer);
#if defined (__cplusplus)