diff options
-rw-r--r-- | lz4frame.h | 47 |
1 files changed, 33 insertions, 14 deletions
@@ -57,8 +57,6 @@ int LZ4F_isError(size_t code); Framing compression functions **************************************/ -typedef void* LZ4F_compressionContext_t; - typedef enum { LZ4F_default=0, max64KB=4, max256KB=5, max1MB=6, max4MB=7} maxBlockSize_t; typedef enum { LZ4F_default=0, blockLinked, blockIndependent} blockMode_t; typedef enum { LZ4F_default=0, contentChecksumEnabled, contentNoChecksum} contentChecksum_t; @@ -68,10 +66,37 @@ typedef struct { maxBlockSize_t maxBlockSize; blockMode_t blockMode; contentChecksum_t contentChecksumFlag; + int autoFlush; } LZ4F_preferences_t; + + +/********************************** + * Simple functions + * *********************************/ +size_t LZ4F_compressFrameBound(size_t srcSize, const LZ4F_preferences_t* preferences); + +size_t LZ4F_compressFrame(void* dstBuffer, size_t dstMaxSize, const void* srcBuffer, size_t srcSize, const LZ4F_preferences_t* preferences); +/* LZ4F_compressFrame() + * Compress an entire srcBuffer into a valid LZ4 frame, as defined by specification v1.4.1, in a single step. + * The most important rule is that dstBuffer MUST be large enough (dstMaxSize) to ensure compression completion even in worst case. + * You can get the minimum value of dstMaxSize by using LZ4F_compressFrameBound() + * If this condition is not respected, LZ4F_compressFrame() will fail (result is an errorCode) + * The LZ4F_preferences_t structure is optional : you can provide NULL as argument. All preferences will be set to default. + * The result of the function is the number of bytes written into dstBuffer. + * The function outputs an error code if it fails (can be tested using LZ4F_isError()) + */ + + + + +/********************************** + * Advanced functions + * *********************************/ + +typedef void* LZ4F_compressionContext_t; + typedef struct { - int autoFlush; /* default is 0 = no autoflush */ int stableSrc; /* unused for the time being, must be 0 */ } LZ4F_compressOptions_t; @@ -83,24 +108,18 @@ size_t LZ4F_getMaxSrcSize(size_t dstMaxSize, const LZ4F_preferences_t* preferenc * The LZ4F_preferences_t structure is optional : you can provide NULL as argument, all preferences will then be set to default. */ - -/* ********************************* - * Compression functions - * *********************************/ - /* Resource Management */ #define LZ4F_VERSION 100 -LZ4F_compressionContext_t LZ4F_createCompressionContext(int version, const LZ4F_preferences_t* preferences); -void LZ4F_freeCompressionContext(LZ4F_compressionContext_t* LZ4F_compressionContext); +LZ4F_errorCode_t LZ4F_createCompressionContext(LZ4F_compressionContext_t* LZ4F_compressionContext, int version, const LZ4F_preferences_t* preferences); +LZ4F_errorCode_t LZ4F_freeCompressionContext(LZ4F_compressionContext_t LZ4F_compressionContext); /* LZ4F_createCompressionContext() : * The first thing to do is to create a compressionContext object, which will be used in all compression operations. * This is achieved using LZ4F_createCompressionContext(), which takes as argument a version and an LZ4F_preferences_t structure. - * The version provided MUST be LZ4F_VERSION. - * It is intended to track potential version differences between a program and an external dynamic library. + * The version provided MUST be LZ4F_VERSION. It is intended to track potential version differences between different binaries. * The LZ4F_preferences_t structure is optional : you can provide NULL as argument, all preferences will then be set to default. - * The result of the function is a pointer to the LZ4F_compressionContext_t object. - * If the pointer is NULL, there was an error during context creation. + * The function will provide a pointer to a fully allocated LZ4F_compressionContext_t object. + * If the result LZ4F_errorCode_t is not zero, there was an error during context creation. * Object can release its memory using LZ4F_freeCompressionContext(); */ |