lz4frame.h in extlz4-0.3

- old
+ new

@@ -30,14 +30,18 @@
    You can contact the author at :
    - LZ4 source repository : https://github.com/lz4/lz4
    - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
 */
 
-/* LZ4F is a stand-alone API to create LZ4-compressed frames
- * conformant with specification v1.5.1.
- * It also offers streaming capabilities.
- * lz4.h is not required when using lz4frame.h.
+/* LZ4F is a stand-alone API able to create and decode LZ4 frames
+ * conformant with specification v1.6.1 in doc/lz4_Frame_format.md .
+ * Generated frames are compatible with `lz4` CLI.
+ *
+ * LZ4F also offers streaming capabilities.
+ *
+ * lz4.h is not required when using lz4frame.h,
+ * except to extract common constant such as LZ4_VERSION_NUMBER.
  * */
 
 #ifndef LZ4F_H_09782039843
 #define LZ4F_H_09782039843
 
@@ -91,12 +95,12 @@
 /*-************************************
  *  Error management
  **************************************/
 typedef size_t LZ4F_errorCode_t;
 
-LZ4FLIB_API unsigned    LZ4F_isError(LZ4F_errorCode_t code);   /**< tells if a `LZ4F_errorCode_t` function result is an error code */
-LZ4FLIB_API const char* LZ4F_getErrorName(LZ4F_errorCode_t code);   /**< return error code string; useful for debugging */
+LZ4FLIB_API unsigned    LZ4F_isError(LZ4F_errorCode_t code);   /**< tells when a function result is an error code */
+LZ4FLIB_API const char* LZ4F_getErrorName(LZ4F_errorCode_t code);   /**< return error code string; for debugging */
 
 
 /*-************************************
  *  Frame compression types
  **************************************/
@@ -157,42 +161,52 @@
 typedef LZ4F_contentChecksum_t contentChecksum_t;
 #endif
 
 /*! LZ4F_frameInfo_t :
  *  makes it possible to set or read frame parameters.
- *  It's not required to set all fields, as long as the structure was initially memset() to zero.
- *  For all fields, 0 sets it to default value */
+ *  Structure must be first init to 0, using memset() or LZ4F_INIT_FRAMEINFO,
+ *  setting all parameters to default.
+ *  It's then possible to update selectively some parameters */
 typedef struct {
-  LZ4F_blockSizeID_t     blockSizeID;          /* max64KB, max256KB, max1MB, max4MB ; 0 == default */
-  LZ4F_blockMode_t       blockMode;            /* LZ4F_blockLinked, LZ4F_blockIndependent ; 0 == default */
-  LZ4F_contentChecksum_t contentChecksumFlag;  /* if enabled, frame is terminated with a 32-bits checksum of decompressed data ; 0 == disabled (default)  */
-  LZ4F_frameType_t       frameType;            /* read-only field : LZ4F_frame or LZ4F_skippableFrame */
-  unsigned long long     contentSize;          /* Size of uncompressed content ; 0 == unknown */
-  unsigned               dictID;               /* Dictionary ID, sent by the compressor to help decoder select the correct dictionary; 0 == no dictID provided */
-  LZ4F_blockChecksum_t   blockChecksumFlag;    /* if enabled, each block is followed by a checksum of block's compressed data ; 0 == disabled (default)  */
+  LZ4F_blockSizeID_t     blockSizeID;         /* max64KB, max256KB, max1MB, max4MB; 0 == default */
+  LZ4F_blockMode_t       blockMode;           /* LZ4F_blockLinked, LZ4F_blockIndependent; 0 == default */
+  LZ4F_contentChecksum_t contentChecksumFlag; /* 1: frame terminated with 32-bit checksum of decompressed data; 0: disabled (default) */
+  LZ4F_frameType_t       frameType;           /* read-only field : LZ4F_frame or LZ4F_skippableFrame */
+  unsigned long long     contentSize;         /* Size of uncompressed content ; 0 == unknown */
+  unsigned               dictID;              /* Dictionary ID, sent by compressor to help decoder select correct dictionary; 0 == no dictID provided */
+  LZ4F_blockChecksum_t   blockChecksumFlag;   /* 1: each block followed by a checksum of block's compressed data; 0: disabled (default) */
 } LZ4F_frameInfo_t;
 
+#define LZ4F_INIT_FRAMEINFO   { 0, 0, 0, 0, 0, 0, 0 }    /* v1.8.3+ */
+
 /*! LZ4F_preferences_t :
- *  makes it possible to supply detailed compression parameters to the stream interface.
- *  It's not required to set all fields, as long as the structure was initially memset() to zero.
+ *  makes it possible to supply advanced compression instructions to streaming interface.
+ *  Structure must be first init to 0, using memset() or LZ4F_INIT_PREFERENCES,
+ *  setting all parameters to default.
  *  All reserved fields must be set to zero. */
 typedef struct {
   LZ4F_frameInfo_t frameInfo;
-  int      compressionLevel;       /* 0 == default (fast mode); values above LZ4HC_CLEVEL_MAX count as LZ4HC_CLEVEL_MAX; values below 0 trigger "fast acceleration", proportional to value */
-  unsigned autoFlush;              /* 1 == always flush, to reduce usage of internal buffers */
-  unsigned reserved[4];            /* must be zero for forward compatibility */
+  int      compressionLevel;    /* 0: default (fast mode); values > LZ4HC_CLEVEL_MAX count as LZ4HC_CLEVEL_MAX; values < 0 trigger "fast acceleration" */
+  unsigned autoFlush;           /* 1: always flush; reduces usage of internal buffers */
+  unsigned favorDecSpeed;       /* 1: parser favors decompression speed vs compression ratio. Only works for high compression modes (>= LZ4HC_CLEVEL_OPT_MIN) */  /* v1.8.2+ */
+  unsigned reserved[3];         /* must be zero for forward compatibility */
 } LZ4F_preferences_t;
 
-LZ4FLIB_API int LZ4F_compressionLevel_max(void);
+#define LZ4F_INIT_PREFERENCES   { LZ4F_INIT_FRAMEINFO, 0, 0, 0, { 0, 0, 0 } }    /* v1.8.3+ */
 
 
 /*-*********************************
 *  Simple compression function
 ***********************************/
+
+LZ4FLIB_API int LZ4F_compressionLevel_max(void);   /* v1.8.0+ */
+
 /*! LZ4F_compressFrameBound() :
- *  Returns the maximum possible size of a frame compressed with LZ4F_compressFrame() given srcSize content and preferences.
- *  Note : this result is only usable with LZ4F_compressFrame(), not with multi-segments compression.
+ *  Returns the maximum possible compressed size with LZ4F_compressFrame() given srcSize and preferences.
+ * `preferencesPtr` is optional. It can be replaced by NULL, in which case, the function will assume default preferences.
+ *  Note : this result is only usable with LZ4F_compressFrame().
+ *         It may also be used with LZ4F_compressUpdate() _if no flush() operation_ is performed.
  */
 LZ4FLIB_API size_t LZ4F_compressFrameBound(size_t srcSize, const LZ4F_preferences_t* preferencesPtr);
 
 /*! LZ4F_compressFrame() :
  *  Compress an entire srcBuffer into a valid LZ4 frame.
@@ -217,12 +231,13 @@
   unsigned reserved[3];
 } LZ4F_compressOptions_t;
 
 /*---   Resource Management   ---*/
 
-#define LZ4F_VERSION 100
+#define LZ4F_VERSION 100    /* This number can be used to check for an incompatible API breaking change */
 LZ4FLIB_API unsigned LZ4F_getVersion(void);
+
 /*! 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.
  * The version provided MUST be LZ4F_VERSION. It is intended to track potential version mismatch, notably when using DLL.
  * The function will provide a pointer to a fully allocated LZ4F_cctx object.
@@ -233,11 +248,13 @@
 LZ4FLIB_API LZ4F_errorCode_t LZ4F_freeCompressionContext(LZ4F_cctx* cctx);
 
 
 /*----    Compression    ----*/
 
+#define LZ4F_HEADER_SIZE_MIN  7   /* LZ4 Frame header size can vary, depending on selected paramaters */
 #define LZ4F_HEADER_SIZE_MAX 19
+
 /*! LZ4F_compressBegin() :
  *  will write the frame header into dstBuffer.
  *  dstCapacity must be >= LZ4F_HEADER_SIZE_MAX bytes.
  * `prefsPtr` is optional : you can provide NULL as argument, all preferences will then be set to default.
  * @return : number of bytes written into dstBuffer for the header
@@ -246,146 +263,344 @@
 LZ4FLIB_API size_t LZ4F_compressBegin(LZ4F_cctx* cctx,
                                       void* dstBuffer, size_t dstCapacity,
                                       const LZ4F_preferences_t* prefsPtr);
 
 /*! LZ4F_compressBound() :
- * Provides dstCapacity given a srcSize to guarantee operation success in worst case situations.
- * prefsPtr is optional : you can provide NULL as argument, preferences will be set to cover worst case scenario.
- * Result is always the same for a srcSize and prefsPtr, so it can be trusted to size reusable buffers.
- * When srcSize==0, LZ4F_compressBound() provides an upper bound for LZ4F_flush() and LZ4F_compressEnd() operations.
+ *  Provides minimum dstCapacity required to guarantee success of
+ *  LZ4F_compressUpdate(), given a srcSize and preferences, for a worst case scenario.
+ *  When srcSize==0, LZ4F_compressBound() provides an upper bound for LZ4F_flush() and LZ4F_compressEnd() instead.
+ *  Note that the result is only valid for a single invocation of LZ4F_compressUpdate().
+ *  When invoking LZ4F_compressUpdate() multiple times,
+ *  if the output buffer is gradually filled up instead of emptied and re-used from its start,
+ *  one must check if there is enough remaining capacity before each invocation, using LZ4F_compressBound().
+ * @return is always the same for a srcSize and prefsPtr.
+ *  prefsPtr is optional : when NULL is provided, preferences will be set to cover worst case scenario.
+ *  tech details :
+ * @return includes the possibility that internal buffer might already be filled by up to (blockSize-1) bytes.
+ *  It also includes frame footer (ending + checksum), since it might be generated by LZ4F_compressEnd().
+ * @return doesn't include frame header, as it was already generated by LZ4F_compressBegin().
  */
 LZ4FLIB_API size_t LZ4F_compressBound(size_t srcSize, const LZ4F_preferences_t* prefsPtr);
 
 /*! LZ4F_compressUpdate() :
- * LZ4F_compressUpdate() can be called repetitively to compress as much data as necessary.
- * An important rule is that dstCapacity MUST be large enough to ensure operation success even in worst case situations.
- * This value is provided by LZ4F_compressBound().
- * If this condition is not respected, LZ4F_compress() will fail (result is an errorCode).
- * LZ4F_compressUpdate() doesn't guarantee error recovery. When an error occurs, compression context must be freed or resized.
+ *  LZ4F_compressUpdate() can be called repetitively to compress as much data as necessary.
+ *  Important rule: dstCapacity MUST be large enough to ensure operation success even in worst case situations.
+ *  This value is provided by LZ4F_compressBound().
+ *  If this condition is not respected, LZ4F_compress() will fail (result is an errorCode).
+ *  LZ4F_compressUpdate() doesn't guarantee error recovery.
+ *  When an error occurs, compression context must be freed or resized.
  * `cOptPtr` is optional : NULL can be provided, in which case all options are set to default.
  * @return : number of bytes written into `dstBuffer` (it can be zero, meaning input data was just buffered).
  *           or an error code if it fails (which can be tested using LZ4F_isError())
  */
-LZ4FLIB_API size_t LZ4F_compressUpdate(LZ4F_cctx* cctx, void* dstBuffer, size_t dstCapacity, const void* srcBuffer, size_t srcSize, const LZ4F_compressOptions_t* cOptPtr);
+LZ4FLIB_API size_t LZ4F_compressUpdate(LZ4F_cctx* cctx,
+                                       void* dstBuffer, size_t dstCapacity,
+                                 const void* srcBuffer, size_t srcSize,
+                                 const LZ4F_compressOptions_t* cOptPtr);
 
 /*! LZ4F_flush() :
- * When data must be generated and sent immediately, without waiting for a block to be completely filled,
- * it's possible to call LZ4_flush(). It will immediately compress any data buffered within cctx.
+ *  When data must be generated and sent immediately, without waiting for a block to be completely filled,
+ *  it's possible to call LZ4_flush(). It will immediately compress any data buffered within cctx.
  * `dstCapacity` must be large enough to ensure the operation will be successful.
  * `cOptPtr` is optional : it's possible to provide NULL, all options will be set to default.
- * @return : number of bytes written into dstBuffer (it can be zero, which means there was no data stored within cctx)
+ * @return : nb of bytes written into dstBuffer (can be zero, when there is no data stored within cctx)
  *           or an error code if it fails (which can be tested using LZ4F_isError())
+ *  Note : LZ4F_flush() is guaranteed to be successful when dstCapacity >= LZ4F_compressBound(0, prefsPtr).
  */
-LZ4FLIB_API size_t LZ4F_flush(LZ4F_cctx* cctx, void* dstBuffer, size_t dstCapacity, const LZ4F_compressOptions_t* cOptPtr);
+LZ4FLIB_API size_t LZ4F_flush(LZ4F_cctx* cctx,
+                              void* dstBuffer, size_t dstCapacity,
+                        const LZ4F_compressOptions_t* cOptPtr);
 
 /*! LZ4F_compressEnd() :
  *  To properly finish an LZ4 frame, invoke LZ4F_compressEnd().
  *  It will flush whatever data remained within `cctx` (like LZ4_flush())
  *  and properly finalize the frame, with an endMark and a checksum.
  * `cOptPtr` is optional : NULL can be provided, in which case all options will be set to default.
- * @return : number of bytes written into dstBuffer (necessarily >= 4 (endMark), or 8 if optional frame checksum is enabled)
+ * @return : nb of bytes written into dstBuffer, necessarily >= 4 (endMark),
  *           or an error code if it fails (which can be tested using LZ4F_isError())
+ *  Note : LZ4F_compressEnd() is guaranteed to be successful when dstCapacity >= LZ4F_compressBound(0, prefsPtr).
  *  A successful call to LZ4F_compressEnd() makes `cctx` available again for another compression task.
  */
-LZ4FLIB_API size_t LZ4F_compressEnd(LZ4F_cctx* cctx, void* dstBuffer, size_t dstCapacity, const LZ4F_compressOptions_t* cOptPtr);
+LZ4FLIB_API size_t LZ4F_compressEnd(LZ4F_cctx* cctx,
+                                    void* dstBuffer, size_t dstCapacity,
+                              const LZ4F_compressOptions_t* cOptPtr);
 
 
 /*-*********************************
 *  Decompression functions
 ***********************************/
 typedef struct LZ4F_dctx_s LZ4F_dctx;   /* incomplete type */
 typedef LZ4F_dctx* LZ4F_decompressionContext_t;   /* compatibility with previous API versions */
 
 typedef struct {
-  unsigned stableDst;    /* pledge that at least 64KB+64Bytes of previously decompressed data remain unmodifed where it was decoded. This optimization skips storage operations in tmp buffers */
+  unsigned stableDst;    /* pledges that last 64KB decompressed data will remain available unmodified. This optimization skips storage operations in tmp buffers. */
   unsigned reserved[3];  /* must be set to zero for forward compatibility */
 } LZ4F_decompressOptions_t;
 
 
 /* Resource management */
 
-/*!LZ4F_createDecompressionContext() :
- * Create an LZ4F_dctx object, to track all decompression operations.
- * The version provided MUST be LZ4F_VERSION.
- * The function provides a pointer to an allocated and initialized LZ4F_dctx object.
- * The result is an errorCode, which can be tested using LZ4F_isError().
- * dctx memory can be released using LZ4F_freeDecompressionContext();
- * The result of LZ4F_freeDecompressionContext() is indicative of the current state of decompressionContext when being released.
- * That is, it should be == 0 if decompression has been completed fully and correctly.
+/*! LZ4F_createDecompressionContext() :
+ *  Create an LZ4F_dctx object, to track all decompression operations.
+ *  The version provided MUST be LZ4F_VERSION.
+ *  The function provides a pointer to an allocated and initialized LZ4F_dctx object.
+ *  The result is an errorCode, which can be tested using LZ4F_isError().
+ *  dctx memory can be released using LZ4F_freeDecompressionContext();
+ *  Result of LZ4F_freeDecompressionContext() indicates current state of decompressionContext when being released.
+ *  That is, it should be == 0 if decompression has been completed fully and correctly.
  */
 LZ4FLIB_API LZ4F_errorCode_t LZ4F_createDecompressionContext(LZ4F_dctx** dctxPtr, unsigned version);
 LZ4FLIB_API LZ4F_errorCode_t LZ4F_freeDecompressionContext(LZ4F_dctx* dctx);
 
 
 /*-***********************************
 *  Streaming decompression functions
 *************************************/
 
+#define LZ4F_MIN_SIZE_TO_KNOW_HEADER_LENGTH 5
+
+/*! LZ4F_headerSize() : v1.9.0+
+ *  Provide the header size of a frame starting at `src`.
+ * `srcSize` must be >= LZ4F_MIN_SIZE_TO_KNOW_HEADER_LENGTH,
+ *  which is enough to decode the header length.
+ * @return : size of frame header
+ *           or an error code, which can be tested using LZ4F_isError()
+ *  note : Frame header size is variable, but is guaranteed to be
+ *         >= LZ4F_HEADER_SIZE_MIN bytes, and <= LZ4F_HEADER_SIZE_MAX bytes.
+ */
+size_t LZ4F_headerSize(const void* src, size_t srcSize);
+
 /*! LZ4F_getFrameInfo() :
  *  This function extracts frame parameters (max blockSize, dictID, etc.).
- *  Its usage is optional.
- *  Extracted information is typically useful for allocation and dictionary.
- *  This function works in 2 situations :
- *   - At the beginning of a new frame, in which case
- *     it will decode information from `srcBuffer`, starting the decoding process.
- *     Input size must be large enough to successfully decode the entire frame header.
- *     Frame header size is variable, but is guaranteed to be <= LZ4F_HEADER_SIZE_MAX bytes.
- *     It's allowed to provide more input data than this minimum.
- *   - After decoding has been started.
- *     In which case, no input is read, frame parameters are extracted from dctx.
- *   - If decoding has barely started, but not yet extracted information from header,
+ *  Its usage is optional: user can call LZ4F_decompress() directly.
+ *
+ *  Extracted information will fill an existing LZ4F_frameInfo_t structure.
+ *  This can be useful for allocation and dictionary identification purposes.
+ *
+ *  LZ4F_getFrameInfo() can work in the following situations :
+ *
+ *  1) At the beginning of a new frame, before any invocation of LZ4F_decompress().
+ *     It will decode header from `srcBuffer`,
+ *     consuming the header and starting the decoding process.
+ *
+ *     Input size must be large enough to contain the full frame header.
+ *     Frame header size can be known beforehand by LZ4F_headerSize().
+ *     Frame header size is variable, but is guaranteed to be >= LZ4F_HEADER_SIZE_MIN bytes,
+ *     and not more than <= LZ4F_HEADER_SIZE_MAX bytes.
+ *     Hence, blindly providing LZ4F_HEADER_SIZE_MAX bytes or more will always work.
+ *     It's allowed to provide more input data than the header size,
+ *     LZ4F_getFrameInfo() will only consume the header.
+ *
+ *     If input size is not large enough,
+ *     aka if it's smaller than header size,
+ *     function will fail and return an error code.
+ *
+ *  2) After decoding has been started,
+ *     it's possible to invoke LZ4F_getFrameInfo() anytime
+ *     to extract already decoded frame parameters stored within dctx.
+ *
+ *     Note that, if decoding has barely started,
+ *     and not yet read enough information to decode the header,
  *     LZ4F_getFrameInfo() will fail.
- *  The number of bytes consumed from srcBuffer will be updated within *srcSizePtr (necessarily <= original value).
- *  Decompression must resume from (srcBuffer + *srcSizePtr).
- * @return : an hint about how many srcSize bytes LZ4F_decompress() expects for next call,
+ *
+ *  The number of bytes consumed from srcBuffer will be updated in *srcSizePtr (necessarily <= original value).
+ *  LZ4F_getFrameInfo() only consumes bytes when decoding has not yet started,
+ *  and when decoding the header has been successful.
+ *  Decompression must then resume from (srcBuffer + *srcSizePtr).
+ *
+ * @return : a hint about how many srcSize bytes LZ4F_decompress() expects for next call,
  *           or an error code which can be tested using LZ4F_isError().
  *  note 1 : in case of error, dctx is not modified. Decoding operation can resume from beginning safely.
  *  note 2 : frame parameters are *copied into* an already allocated LZ4F_frameInfo_t structure.
  */
 LZ4FLIB_API size_t LZ4F_getFrameInfo(LZ4F_dctx* dctx,
                                      LZ4F_frameInfo_t* frameInfoPtr,
                                      const void* srcBuffer, size_t* srcSizePtr);
 
 /*! LZ4F_decompress() :
  *  Call this function repetitively to regenerate compressed data from `srcBuffer`.
- *  The function will attempt to decode up to *srcSizePtr bytes from srcBuffer, into dstBuffer of capacity *dstSizePtr.
+ *  The function will read up to *srcSizePtr bytes from srcBuffer,
+ *  and decompress data into dstBuffer, of capacity *dstSizePtr.
  *
- *  The number of bytes regenerated into dstBuffer is provided within *dstSizePtr (necessarily <= original value).
+ *  The nb of bytes consumed from srcBuffer will be written into *srcSizePtr (necessarily <= original value).
+ *  The nb of bytes decompressed into dstBuffer will be written into *dstSizePtr (necessarily <= original value).
  *
- *  The number of bytes consumed from srcBuffer is provided within *srcSizePtr (necessarily <= original value).
- *  Number of bytes consumed can be < number of bytes provided.
- *  It typically happens when dstBuffer is not large enough to contain all decoded data.
+ *  The function does not necessarily read all input bytes, so always check value in *srcSizePtr.
  *  Unconsumed source data must be presented again in subsequent invocations.
  *
- * `dstBuffer` content is expected to be flushed between each invocation, as its content will be overwritten.
- * `dstBuffer` itself can be changed at will between each consecutive function invocation.
+ * `dstBuffer` can freely change between each consecutive function invocation.
+ * `dstBuffer` content will be overwritten.
  *
  * @return : an hint of how many `srcSize` bytes LZ4F_decompress() expects for next call.
  *  Schematically, it's the size of the current (or remaining) compressed block + header of next block.
  *  Respecting the hint provides some small speed benefit, because it skips intermediate buffers.
  *  This is just a hint though, it's always possible to provide any srcSize.
+ *
  *  When a frame is fully decoded, @return will be 0 (no more data expected).
+ *  When provided with more bytes than necessary to decode a frame,
+ *  LZ4F_decompress() will stop reading exactly at end of current frame, and @return 0.
+ *
  *  If decompression failed, @return is an error code, which can be tested using LZ4F_isError().
+ *  After a decompression error, the `dctx` context is not resumable.
+ *  Use LZ4F_resetDecompressionContext() to return to clean state.
  *
  *  After a frame is fully decoded, dctx can be used again to decompress another frame.
- *  After a decompression error, use LZ4F_resetDecompressionContext() before re-using dctx, to return to clean state.
  */
 LZ4FLIB_API size_t LZ4F_decompress(LZ4F_dctx* dctx,
                                    void* dstBuffer, size_t* dstSizePtr,
                                    const void* srcBuffer, size_t* srcSizePtr,
                                    const LZ4F_decompressOptions_t* dOptPtr);
 
 
-/*! LZ4F_resetDecompressionContext() : v1.8.0
+/*! LZ4F_resetDecompressionContext() : added in v1.8.0
  *  In case of an error, the context is left in "undefined" state.
  *  In which case, it's necessary to reset it, before re-using it.
- *  This method can also be used to abruptly stop an unfinished decompression,
- *  and start a new one using the same context. */
+ *  This method can also be used to abruptly stop any unfinished decompression,
+ *  and start a new one using same context resources. */
 LZ4FLIB_API void LZ4F_resetDecompressionContext(LZ4F_dctx* dctx);   /* always successful */
 
 
 
 #if defined (__cplusplus)
 }
 #endif
 
 #endif  /* LZ4F_H_09782039843 */
+
+#if defined(LZ4F_STATIC_LINKING_ONLY) && !defined(LZ4F_H_STATIC_09782039843)
+#define LZ4F_H_STATIC_09782039843
+
+#if defined (__cplusplus)
+extern "C" {
+#endif
+
+/* These declarations are not stable and may change in the future.
+ * They are therefore only safe to depend on
+ * when the caller is statically linked against the library.
+ * To access their declarations, define LZ4F_STATIC_LINKING_ONLY.
+ *
+ * By default, these symbols aren't published into shared/dynamic libraries.
+ * You can override this behavior and force them to be published
+ * by defining LZ4F_PUBLISH_STATIC_FUNCTIONS.
+ * Use at your own risk.
+ */
+#ifdef LZ4F_PUBLISH_STATIC_FUNCTIONS
+#define LZ4FLIB_STATIC_API LZ4FLIB_API
+#else
+#define LZ4FLIB_STATIC_API
+#endif
+
+
+/* ---   Error List   --- */
+#define LZ4F_LIST_ERRORS(ITEM) \
+        ITEM(OK_NoError) \
+        ITEM(ERROR_GENERIC) \
+        ITEM(ERROR_maxBlockSize_invalid) \
+        ITEM(ERROR_blockMode_invalid) \
+        ITEM(ERROR_contentChecksumFlag_invalid) \
+        ITEM(ERROR_compressionLevel_invalid) \
+        ITEM(ERROR_headerVersion_wrong) \
+        ITEM(ERROR_blockChecksum_invalid) \
+        ITEM(ERROR_reservedFlag_set) \
+        ITEM(ERROR_allocation_failed) \
+        ITEM(ERROR_srcSize_tooLarge) \
+        ITEM(ERROR_dstMaxSize_tooSmall) \
+        ITEM(ERROR_frameHeader_incomplete) \
+        ITEM(ERROR_frameType_unknown) \
+        ITEM(ERROR_frameSize_wrong) \
+        ITEM(ERROR_srcPtr_wrong) \
+        ITEM(ERROR_decompressionFailed) \
+        ITEM(ERROR_headerChecksum_invalid) \
+        ITEM(ERROR_contentChecksum_invalid) \
+        ITEM(ERROR_frameDecoding_alreadyStarted) \
+        ITEM(ERROR_maxCode)
+
+#define LZ4F_GENERATE_ENUM(ENUM) LZ4F_##ENUM,
+
+/* enum list is exposed, to handle specific errors */
+typedef enum { LZ4F_LIST_ERRORS(LZ4F_GENERATE_ENUM)
+              _LZ4F_dummy_error_enum_for_c89_never_used } LZ4F_errorCodes;
+
+LZ4FLIB_STATIC_API LZ4F_errorCodes LZ4F_getErrorCode(size_t functionResult);
+
+LZ4FLIB_STATIC_API size_t LZ4F_getBlockSize(unsigned);
+
+/**********************************
+ *  Bulk processing dictionary API
+ *********************************/
+
+/* A Dictionary is useful for the compression of small messages (KB range).
+ * It dramatically improves compression efficiency.
+ *
+ * LZ4 can ingest any input as dictionary, though only the last 64 KB are useful.
+ * Best results are generally achieved by using Zstandard's Dictionary Builder
+ * to generate a high-quality dictionary from a set of samples.
+ *
+ * Loading a dictionary has a cost, since it involves construction of tables.
+ * The Bulk processing dictionary API makes it possible to share this cost
+ * over an arbitrary number of compression jobs, even concurrently,
+ * markedly improving compression latency for these cases.
+ *
+ * The same dictionary will have to be used on the decompression side
+ * for decoding to be successful.
+ * To help identify the correct dictionary at decoding stage,
+ * the frame header allows optional embedding of a dictID field.
+ */
+typedef struct LZ4F_CDict_s LZ4F_CDict;
+
+/*! LZ4_createCDict() :
+ *  When compressing multiple messages / blocks using the same dictionary, it's recommended to load it just once.
+ *  LZ4_createCDict() will create a digested dictionary, ready to start future compression operations without startup delay.
+ *  LZ4_CDict can be created once and shared by multiple threads concurrently, since its usage is read-only.
+ * `dictBuffer` can be released after LZ4_CDict creation, since its content is copied within CDict */
+LZ4FLIB_STATIC_API LZ4F_CDict* LZ4F_createCDict(const void* dictBuffer, size_t dictSize);
+LZ4FLIB_STATIC_API void        LZ4F_freeCDict(LZ4F_CDict* CDict);
+
+
+/*! LZ4_compressFrame_usingCDict() :
+ *  Compress an entire srcBuffer into a valid LZ4 frame using a digested Dictionary.
+ *  cctx must point to a context created by LZ4F_createCompressionContext().
+ *  If cdict==NULL, compress without a dictionary.
+ *  dstBuffer MUST be >= LZ4F_compressFrameBound(srcSize, preferencesPtr).
+ *  If this condition is not respected, function will fail (@return an errorCode).
+ *  The LZ4F_preferences_t structure is optional : you may provide NULL as argument,
+ *  but it's not recommended, as it's the only way to provide dictID in the frame header.
+ * @return : number of bytes written into dstBuffer.
+ *           or an error code if it fails (can be tested using LZ4F_isError()) */
+LZ4FLIB_STATIC_API size_t LZ4F_compressFrame_usingCDict(
+    LZ4F_cctx* cctx,
+    void* dst, size_t dstCapacity,
+    const void* src, size_t srcSize,
+    const LZ4F_CDict* cdict,
+    const LZ4F_preferences_t* preferencesPtr);
+
+
+/*! LZ4F_compressBegin_usingCDict() :
+ *  Inits streaming dictionary compression, and writes the frame header into dstBuffer.
+ *  dstCapacity must be >= LZ4F_HEADER_SIZE_MAX bytes.
+ * `prefsPtr` is optional : you may provide NULL as argument,
+ *  however, it's the only way to provide dictID in the frame header.
+ * @return : number of bytes written into dstBuffer for the header,
+ *           or an error code (which can be tested using LZ4F_isError()) */
+LZ4FLIB_STATIC_API size_t LZ4F_compressBegin_usingCDict(
+    LZ4F_cctx* cctx,
+    void* dstBuffer, size_t dstCapacity,
+    const LZ4F_CDict* cdict,
+    const LZ4F_preferences_t* prefsPtr);
+
+
+/*! LZ4F_decompress_usingDict() :
+ *  Same as LZ4F_decompress(), using a predefined dictionary.
+ *  Dictionary is used "in place", without any preprocessing.
+ *  It must remain accessible throughout the entire frame decoding. */
+LZ4FLIB_STATIC_API size_t LZ4F_decompress_usingDict(
+    LZ4F_dctx* dctxPtr,
+    void* dstBuffer, size_t* dstSizePtr,
+    const void* srcBuffer, size_t* srcSizePtr,
+    const void* dict, size_t dictSize,
+    const LZ4F_decompressOptions_t* decompressOptionsPtr);
+
+#if defined (__cplusplus)
+}
+#endif
+
+#endif  /* defined(LZ4F_STATIC_LINKING_ONLY) && !defined(LZ4F_H_STATIC_09782039843) */