Merge branch 'master' into usb

.vscode/settings.json

@@ -128,7 +128,8 @@
         "current.h": "c",
         "proc-types.h": "c",
         "traceback.h": "c",
-        "bitcount.h": "c"
+        "bitcount.h": "c",
+        "limits.h": "c"
     },
     "C_Cpp.errorSquiggles": "Enabled",
     "esbonio.sphinx.confDir": ""

docs/kernel/core_api/kernel_api.md

@@ -311,3 +311,45 @@
 **...**
 
   可变参数
+
+### 内存操作
+
+#### `void *memcpy(void *dst, const void *src, uint64_t size)`
+
+##### 描述
+
+  将内存从src处拷贝到dst处。
+
+##### 参数
+
+**dst**
+
+  指向目标地址的指针
+
+**src**
+
+  指向源地址的指针
+
+**size**
+
+  待拷贝的数据大小
+
+#### `void *memmove(void *dst, const void *src, uint64_t size)`
+
+##### 描述
+
+  与`memcpy()`类似，但是在源数据区域与目标数据区域之间存在重合时，该函数能防止数据被错误的覆盖。
+
+##### 参数
+
+**dst**
+
+  指向目标地址的指针
+
+**src**
+
+  指向源地址的指针
+
+**size**
+
+  待拷贝的数据大小

kernel/common/glib.c

@@ -25,4 +25,35 @@ void __experimental_beep(uint64_t times)
     // 延迟一段时间
     for(uint64_t i=0;i<times;++i)
         pause();
+}
+
+/**
+ * @brief 将数据从src搬运到dst，并能正确处理地址重叠的问题
+ * 
+ * @param dst 目标地址指针
+ * @param src 源地址指针
+ * @param size 大小
+ * @return void* 指向目标地址的指针
+ */
+void *memmove(void *dst, const void *src, uint64_t size)
+{
+    const char *_src = src;
+	char *_dst = dst;
+
+	if (!size)
+		return dst;
+
+	// 当源地址大于目标地址时，使用memcpy来完成
+	if (dst <= src)
+		return memcpy(dst, src, size);
+
+	// 当源地址小于目标地址时，为防止重叠覆盖，因此从后往前拷贝
+	_src += size;
+	_dst += size;
+
+	// 逐字节拷贝
+	while (size--)
+		*--_dst = *--_src;
+
+	return dst;
 }

kernel/common/glib.h

@@ -552,4 +552,14 @@ static __always_inline uint32_t __read4b(uint64_t vaddr)
                  : "a"(vaddr)
                  : "memory");
     return retval;
-}
+}
+
+/**
+ * @brief 将数据从src搬运到dst，并能正确处理地址重叠的问题
+ * 
+ * @param dst 目标地址指针
+ * @param src 源地址指针
+ * @param size 大小
+ * @return void* 指向目标地址的指针
+ */
+void *memmove(void *dst, const void *src, uint64_t size);

kernel/common/lz4.h

@@ -0,0 +1,771 @@
+/*
+ *  LZ4 - Fast LZ compression algorithm
+ *  Header File
+ *  Copyright (C) 2011-present, Yann Collet.
+
+   BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are
+   met:
+
+       * Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above
+   copyright notice, this list of conditions and the following disclaimer
+   in the documentation and/or other materials provided with the
+   distribution.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+   You can contact the author at :
+    - LZ4 homepage : http://www.lz4.org
+    - LZ4 source repository : https://github.com/lz4/lz4
+*/
+#if defined(__cplusplus)
+extern "C"
+{
+#endif
+
+#ifndef LZ4_H_2983827168210
+#define LZ4_H_2983827168210
+
+/* --- Dependency --- */
+#include <common/stddef.h> /* size_t */
+
+/**
+  Introduction
+
+  LZ4 is lossless compression algorithm, providing compression speed >500 MB/s per core,
+  scalable with multi-cores CPU. It features an extremely fast decoder, with speed in
+  multiple GB/s per core, typically reaching RAM speed limits on multi-core systems.
+
+  The LZ4 compression library provides in-memory compression and decompression functions.
+  It gives full buffer control to user.
+  Compression can be done in:
+    - a single step (described as Simple Functions)
+    - a single step, reusing a context (described in Advanced Functions)
+    - unbounded multiple steps (described as Streaming compression)
+
+  lz4.h generates and decodes LZ4-compressed blocks (doc/lz4_Block_format.md).
+  Decompressing such a compressed block requires additional metadata.
+  Exact metadata depends on exact decompression function.
+  For the typical case of LZ4_decompress_safe(),
+  metadata includes block's compressed size, and maximum bound of decompressed size.
+  Each application is free to encode and pass such metadata in whichever way it wants.
+
+  lz4.h only handle blocks, it can not generate Frames.
+
+  Blocks are different from Frames (doc/lz4_Frame_format.md).
+  Frames bundle both blocks and metadata in a specified manner.
+  Embedding metadata is required for compressed data to be self-contained and portable.
+  Frame format is delivered through a companion API, declared in lz4frame.h.
+  The `lz4` CLI can only manage frames.
+*/
+
+/*^***************************************************************
+ *  Export parameters
+ *****************************************************************/
+/*
+ *  LZ4_DLL_EXPORT :
+ *  Enable exporting of functions when building a Windows DLL
+ *  LZ4LIB_VISIBILITY :
+ *  Control library symbols visibility.
+ */
+#ifndef LZ4LIB_VISIBILITY
+#if defined(__GNUC__) && (__GNUC__ >= 4)
+#define LZ4LIB_VISIBILITY __attribute__((visibility("default")))
+#else
+#define LZ4LIB_VISIBILITY
+#endif
+#endif
+#if defined(LZ4_DLL_EXPORT) && (LZ4_DLL_EXPORT == 1)
+#define LZ4LIB_API __declspec(dllexport) LZ4LIB_VISIBILITY
+#elif defined(LZ4_DLL_IMPORT) && (LZ4_DLL_IMPORT == 1)
+#define LZ4LIB_API __declspec(dllimport) LZ4LIB_VISIBILITY /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/
+#else
+#define LZ4LIB_API LZ4LIB_VISIBILITY
+#endif
+
+/*------   Version   ------*/
+#define LZ4_VERSION_MAJOR 1   /* for breaking interface changes  */
+#define LZ4_VERSION_MINOR 9   /* for new (non-breaking) interface capabilities */
+#define LZ4_VERSION_RELEASE 3 /* for tweaks, bug-fixes, or development */
+
+#define LZ4_VERSION_NUMBER (LZ4_VERSION_MAJOR * 100 * 100 + LZ4_VERSION_MINOR * 100 + LZ4_VERSION_RELEASE)
+
+#define LZ4_LIB_VERSION LZ4_VERSION_MAJOR.LZ4_VERSION_MINOR.LZ4_VERSION_RELEASE
+#define LZ4_QUOTE(str) #str
+#define LZ4_EXPAND_AND_QUOTE(str) LZ4_QUOTE(str)
+#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION)
+
+    LZ4LIB_API int LZ4_versionNumber(void);         /**< library version number; useful to check dll version */
+    LZ4LIB_API const char *LZ4_versionString(void); /**< library version string; useful to check dll version */
+
+/*-************************************
+ *  Tuning parameter
+ **************************************/
+/*!
+ * LZ4_MEMORY_USAGE :
+ * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
+ * Increasing memory usage improves compression ratio.
+ * Reduced memory usage may improve speed, thanks to better cache locality.
+ * Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
+ */
+#ifndef LZ4_MEMORY_USAGE
+#define LZ4_MEMORY_USAGE 14
+#endif
+
+    /*-************************************
+     *  Simple Functions
+     **************************************/
+    /*! LZ4_compress_default() :
+     *  Compresses 'srcSize' bytes from buffer 'src'
+     *  into already allocated 'dst' buffer of size 'dstCapacity'.
+     *  Compression is guaranteed to succeed if 'dstCapacity' >= LZ4_compressBound(srcSize).
+     *  It also runs faster, so it's a recommended setting.
+     *  If the function cannot compress 'src' into a more limited 'dst' budget,
+     *  compression stops *immediately*, and the function result is zero.
+     *  In which case, 'dst' content is undefined (invalid).
+     *      srcSize : max supported value is LZ4_MAX_INPUT_SIZE.
+     *      dstCapacity : size of buffer 'dst' (which must be already allocated)
+     *     @return  : the number of bytes written into buffer 'dst' (necessarily <= dstCapacity)
+     *                or 0 if compression fails
+     * Note : This function is protected against buffer overflow scenarios (never writes outside 'dst' buffer, nor read outside 'source' buffer).
+     */
+    LZ4LIB_API int LZ4_compress_default(const char *src, char *dst, int srcSize, int dstCapacity);
+
+    /*! LZ4_decompress_safe() :
+     *  compressedSize : is the exact complete size of the compressed block.
+     *  dstCapacity : is the size of destination buffer (which must be already allocated), presumed an upper bound of decompressed size.
+     * @return : the number of bytes decompressed into destination buffer (necessarily <= dstCapacity)
+     *           If destination buffer is not large enough, decoding will stop and output an error code (negative value).
+     *           If the source stream is detected malformed, the function will stop decoding and return a negative result.
+     * Note 1 : This function is protected against malicious data packets :
+     *          it will never writes outside 'dst' buffer, nor read outside 'source' buffer,
+     *          even if the compressed block is maliciously modified to order the decoder to do these actions.
+     *          In such case, the decoder stops immediately, and considers the compressed block malformed.
+     * Note 2 : compressedSize and dstCapacity must be provided to the function, the compressed block does not contain them.
+     *          The implementation is free to send / store / derive this information in whichever way is most beneficial.
+     *          If there is a need for a different format which bundles together both compressed data and its metadata, consider looking at lz4frame.h instead.
+     */
+    LZ4LIB_API int LZ4_decompress_safe(const char *src, char *dst, int compressedSize, int dstCapacity);
+
+/*-************************************
+ *  Advanced Functions
+ **************************************/
+#define LZ4_MAX_INPUT_SIZE 0x7E000000 /* 2 113 929 216 bytes */
+#define LZ4_COMPRESSBOUND(isize) ((unsigned)(isize) > (unsigned)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize) / 255) + 16)
+
+    /*! LZ4_compressBound() :
+        Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible)
+        This function is primarily useful for memory allocation purposes (destination buffer size).
+        Macro LZ4_COMPRESSBOUND() is also provided for compilation-time evaluation (stack memory allocation for example).
+        Note that LZ4_compress_default() compresses faster when dstCapacity is >= LZ4_compressBound(srcSize)
+            inputSize  : max supported value is LZ4_MAX_INPUT_SIZE
+            return : maximum output size in a "worst case" scenario
+                  or 0, if input size is incorrect (too large or negative)
+    */
+    LZ4LIB_API int LZ4_compressBound(int inputSize);
+
+    /*! LZ4_compress_fast() :
+        Same as LZ4_compress_default(), but allows selection of "acceleration" factor.
+        The larger the acceleration value, the faster the algorithm, but also the lesser the compression.
+        It's a trade-off. It can be fine tuned, with each successive value providing roughly +~3% to speed.
+        An acceleration value of "1" is the same as regular LZ4_compress_default()
+        Values <= 0 will be replaced by LZ4_ACCELERATION_DEFAULT (currently == 1, see lz4.c).
+        Values > LZ4_ACCELERATION_MAX will be replaced by LZ4_ACCELERATION_MAX (currently == 65537, see lz4.c).
+    */
+    LZ4LIB_API int LZ4_compress_fast(const char *src, char *dst, int srcSize, int dstCapacity, int acceleration);
+
+    /*! LZ4_compress_fast_extState() :
+     *  Same as LZ4_compress_fast(), using an externally allocated memory space for its state.
+     *  Use LZ4_sizeofState() to know how much memory must be allocated,
+     *  and allocate it on 8-bytes boundaries (using `malloc()` typically).
+     *  Then, provide this buffer as `void* state` to compression function.
+     */
+    LZ4LIB_API int LZ4_sizeofState(void);
+    LZ4LIB_API int LZ4_compress_fast_extState(void *state, const char *src, char *dst, int srcSize, int dstCapacity, int acceleration);
+
+    /*! LZ4_compress_destSize() :
+     *  Reverse the logic : compresses as much data as possible from 'src' buffer
+     *  into already allocated buffer 'dst', of size >= 'targetDestSize'.
+     *  This function either compresses the entire 'src' content into 'dst' if it's large enough,
+     *  or fill 'dst' buffer completely with as much data as possible from 'src'.
+     *  note: acceleration parameter is fixed to "default".
+     *
+     * *srcSizePtr : will be modified to indicate how many bytes where read from 'src' to fill 'dst'.
+     *               New value is necessarily <= input value.
+     * @return : Nb bytes written into 'dst' (necessarily <= targetDestSize)
+     *           or 0 if compression fails.
+     *
+     * Note : from v1.8.2 to v1.9.1, this function had a bug (fixed un v1.9.2+):
+     *        the produced compressed content could, in specific circumstances,
+     *        require to be decompressed into a destination buffer larger
+     *        by at least 1 byte than the content to decompress.
+     *        If an application uses `LZ4_compress_destSize()`,
+     *        it's highly recommended to update liblz4 to v1.9.2 or better.
+     *        If this can't be done or ensured,
+     *        the receiving decompression function should provide
+     *        a dstCapacity which is > decompressedSize, by at least 1 byte.
+     *        See https://github.com/lz4/lz4/issues/859 for details
+     */
+    LZ4LIB_API int LZ4_compress_destSize(const char *src, char *dst, int *srcSizePtr, int targetDstSize);
+
+    /*! LZ4_decompress_safe_partial() :
+     *  Decompress an LZ4 compressed block, of size 'srcSize' at position 'src',
+     *  into destination buffer 'dst' of size 'dstCapacity'.
+     *  Up to 'targetOutputSize' bytes will be decoded.
+     *  The function stops decoding on reaching this objective.
+     *  This can be useful to boost performance
+     *  whenever only the beginning of a block is required.
+     *
+     * @return : the number of bytes decoded in `dst` (necessarily <= targetOutputSize)
+     *           If source stream is detected malformed, function returns a negative result.
+     *
+     *  Note 1 : @return can be < targetOutputSize, if compressed block contains less data.
+     *
+     *  Note 2 : targetOutputSize must be <= dstCapacity
+     *
+     *  Note 3 : this function effectively stops decoding on reaching targetOutputSize,
+     *           so dstCapacity is kind of redundant.
+     *           This is because in older versions of this function,
+     *           decoding operation would still write complete sequences.
+     *           Therefore, there was no guarantee that it would stop writing at exactly targetOutputSize,
+     *           it could write more bytes, though only up to dstCapacity.
+     *           Some "margin" used to be required for this operation to work properly.
+     *           Thankfully, this is no longer necessary.
+     *           The function nonetheless keeps the same signature, in an effort to preserve API compatibility.
+     *
+     *  Note 4 : If srcSize is the exact size of the block,
+     *           then targetOutputSize can be any value,
+     *           including larger than the block's decompressed size.
+     *           The function will, at most, generate block's decompressed size.
+     *
+     *  Note 5 : If srcSize is _larger_ than block's compressed size,
+     *           then targetOutputSize **MUST** be <= block's decompressed size.
+     *           Otherwise, *silent corruption will occur*.
+     */
+    LZ4LIB_API int LZ4_decompress_safe_partial(const char *src, char *dst, int srcSize, int targetOutputSize, int dstCapacity);
+
+    /*-*********************************************
+     *  Streaming Compression Functions
+     ***********************************************/
+    typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */
+
+    LZ4LIB_API LZ4_stream_t *LZ4_createStream(void);
+    LZ4LIB_API int LZ4_freeStream(LZ4_stream_t *streamPtr);
+
+    /*! LZ4_resetStream_fast() : v1.9.0+
+     *  Use this to prepare an LZ4_stream_t for a new chain of dependent blocks
+     *  (e.g., LZ4_compress_fast_continue()).
+     *
+     *  An LZ4_stream_t must be initialized once before usage.
+     *  This is automatically done when created by LZ4_createStream().
+     *  However, should the LZ4_stream_t be simply declared on stack (for example),
+     *  it's necessary to initialize it first, using LZ4_initStream().
+     *
+     *  After init, start any new stream with LZ4_resetStream_fast().
+     *  A same LZ4_stream_t can be re-used multiple times consecutively
+     *  and compress multiple streams,
+     *  provided that it starts each new stream with LZ4_resetStream_fast().
+     *
+     *  LZ4_resetStream_fast() is much faster than LZ4_initStream(),
+     *  but is not compatible with memory regions containing garbage data.
+     *
+     *  Note: it's only useful to call LZ4_resetStream_fast()
+     *        in the context of streaming compression.
+     *        The *extState* functions perform their own resets.
+     *        Invoking LZ4_resetStream_fast() before is redundant, and even counterproductive.
+     */
+    LZ4LIB_API void LZ4_resetStream_fast(LZ4_stream_t *streamPtr);
+
+    /*! LZ4_loadDict() :
+     *  Use this function to reference a static dictionary into LZ4_stream_t.
+     *  The dictionary must remain available during compression.
+     *  LZ4_loadDict() triggers a reset, so any previous data will be forgotten.
+     *  The same dictionary will have to be loaded on decompression side for successful decoding.
+     *  Dictionary are useful for better compression of small data (KB range).
+     *  While LZ4 accept any input as dictionary,
+     *  results are generally better when using Zstandard's Dictionary Builder.
+     *  Loading a size of 0 is allowed, and is the same as reset.
+     * @return : loaded dictionary size, in bytes (necessarily <= 64 KB)
+     */
+    LZ4LIB_API int LZ4_loadDict(LZ4_stream_t *streamPtr, const char *dictionary, int dictSize);
+
+    /*! LZ4_compress_fast_continue() :
+     *  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.
+     *
+     * @return : size of compressed block
+     *           or 0 if there is an error (typically, cannot fit into 'dst').
+     *
+     *  Note 1 : Each invocation to LZ4_compress_fast_continue() generates a new block.
+     *           Each block has precise boundaries.
+     *           Each block must be decompressed separately, calling LZ4_decompress_*() with relevant metadata.
+     *           It's not possible to append blocks together and expect a single invocation of LZ4_decompress_*() to decompress them together.
+     *
+     *  Note 2 : The previous 64KB of source data is __assumed__ to remain present, unmodified, at same address in memory !
+     *
+     *  Note 3 : When input is structured as a double-buffer, each buffer can have any size, including < 64 KB.
+     *           Make sure that buffers are separated, by at least one byte.
+     *           This construction ensures that each block only depends on previous block.
+     *
+     *  Note 4 : If input buffer is a ring-buffer, it can have any size, including < 64 KB.
+     *
+     *  Note 5 : After an error, the stream status is undefined (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 last 64KB data cannot be guaranteed to remain available at its current memory location,
+     *  save it into a safer place (char* safeBuffer).
+     *  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 maxDictSize);
+
+    /*-**********************************************
+     *  Streaming Decompression Functions
+     *  Bufferless synchronous API
+     ************************************************/
+    typedef union LZ4_streamDecode_u LZ4_streamDecode_t; /* tracking context */
+
+    /*! LZ4_createStreamDecode() and LZ4_freeStreamDecode() :
+     *  creation / destruction of streaming decompression tracking context.
+     *  A tracking context can be re-used multiple times.
+     */
+    LZ4LIB_API LZ4_streamDecode_t *LZ4_createStreamDecode(void);
+    LZ4LIB_API int LZ4_freeStreamDecode(LZ4_streamDecode_t *LZ4_stream);
+
+    /*! LZ4_setStreamDecode() :
+     *  An LZ4_streamDecode_t context can be allocated once and re-used multiple times.
+     *  Use this function to start decompression of a new stream of blocks.
+     *  A dictionary can optionally be set. Use NULL or size 0 for a reset order.
+     *  Dictionary is presumed stable : it must remain accessible and unmodified during next decompression.
+     * @return : 1 if OK, 0 if error
+     */
+    LZ4LIB_API int LZ4_setStreamDecode(LZ4_streamDecode_t *LZ4_streamDecode, const char *dictionary, int dictSize);
+
+    /*! LZ4_decoderRingBufferSize() : v1.8.2+
+     *  Note : in a ring buffer scenario (optional),
+     *  blocks are presumed decompressed next to each other
+     *  up to the moment there is not enough remaining space for next block (remainingSize < maxBlockSize),
+     *  at which stage it resumes from beginning of ring buffer.
+     *  When setting such a ring buffer for streaming decompression,
+     *  provides the minimum size of this ring buffer
+     *  to be compatible with any source respecting maxBlockSize condition.
+     * @return : minimum ring buffer size,
+     *           or 0 if there is an error (invalid maxBlockSize).
+     */
+    LZ4LIB_API int LZ4_decoderRingBufferSize(int maxBlockSize);
+#define LZ4_DECODER_RING_BUFFER_SIZE(maxBlockSize) (65536 + 14 + (maxBlockSize)) /* for static allocation; maxBlockSize presumed valid */
+
+    /*! LZ4_decompress_*_continue() :
+     *  These decoding functions allow decompression of consecutive blocks in "streaming" mode.
+     *  A block is an unsplittable entity, it must be presented entirely to a decompression function.
+     *  Decompression functions only accepts one block at a time.
+     *  The last 64KB of previously decoded data *must* remain available and unmodified at the memory position where they were decoded.
+     *  If less than 64KB of data has been decoded, all the data must be present.
+     *
+     *  Special : if decompression side sets a ring buffer, it must respect one of the following conditions :
+     *  - Decompression buffer size is _at least_ LZ4_decoderRingBufferSize(maxBlockSize).
+     *    maxBlockSize is the maximum size of any single block. It can have any value > 16 bytes.
+     *    In which case, encoding and decoding buffers do not need to be synchronized.
+     *    Actually, data can be produced by any source compliant with LZ4 format specification, and respecting maxBlockSize.
+     *  - Synchronized mode :
+     *    Decompression buffer size is _exactly_ the same as compression buffer size,
+     *    and follows exactly same update rule (block boundaries at same positions),
+     *    and decoding function is provided with exact decompressed size of each block (exception for last block of the stream),
+     *    _then_ decoding & encoding ring buffer can have any size, including small ones ( < 64 KB).
+     *  - Decompression buffer is larger than encoding buffer, by a minimum of maxBlockSize more bytes.
+     *    In which case, encoding and decoding buffers do not need to be synchronized,
+     *    and encoding ring buffer can have any size, including small ones ( < 64 KB).
+     *
+     *  Whenever these conditions are not possible,
+     *  save the last 64KB of decoded data into a safe buffer where it can't be modified during decompression,
+     *  then indicate where this data is saved using LZ4_setStreamDecode(), before decompressing next block.
+     */
+    LZ4LIB_API int LZ4_decompress_safe_continue(LZ4_streamDecode_t *LZ4_streamDecode, const char *src, char *dst, int srcSize, int dstCapacity);
+
+    /*! LZ4_decompress_*_usingDict() :
+     *  These decoding functions work the same as
+     *  a combination of LZ4_setStreamDecode() followed by LZ4_decompress_*_continue()
+     *  They are stand-alone, and don't need an LZ4_streamDecode_t structure.
+     *  Dictionary is presumed stable : it must remain accessible and unmodified during decompression.
+     *  Performance tip : Decompression speed can be substantially increased
+     *                    when dst == dictStart + dictSize.
+     */
+    LZ4LIB_API int LZ4_decompress_safe_usingDict(const char *src, char *dst, int srcSize, int dstCapcity, const char *dictStart, int dictSize);
+
+#endif /* LZ4_H_2983827168210 */
+
+    /*^*************************************
+     * !!!!!!   STATIC LINKING ONLY   !!!!!!
+     ***************************************/
+
+    /*-****************************************************************************
+     * Experimental section
+     *
+     * Symbols declared in this section must be considered unstable. Their
+     * signatures or semantics may change, or they may be removed altogether in the
+     * future. They are therefore only safe to depend on when the caller is
+     * statically linked against the library.
+     *
+     * To protect against unsafe usage, not only are the declarations guarded,
+     * the definitions are hidden by default
+     * when building LZ4 as a shared/dynamic library.
+     *
+     * In order to access these declarations,
+     * define LZ4_STATIC_LINKING_ONLY in your application
+     * before including LZ4's headers.
+     *
+     * In order to make their implementations accessible dynamically, you must
+     * define LZ4_PUBLISH_STATIC_FUNCTIONS when building the LZ4 library.
+     ******************************************************************************/
+
+#ifdef LZ4_STATIC_LINKING_ONLY
+
+#ifndef LZ4_STATIC_3504398509
+#define LZ4_STATIC_3504398509
+
+#ifdef LZ4_PUBLISH_STATIC_FUNCTIONS
+#define LZ4LIB_STATIC_API LZ4LIB_API
+#else
+#define LZ4LIB_STATIC_API
+#endif
+
+    /*! LZ4_compress_fast_extState_fastReset() :
+     *  A variant of LZ4_compress_fast_extState().
+     *
+     *  Using this variant avoids an expensive initialization step.
+     *  It is only safe to call if the state buffer is known to be correctly initialized already
+     *  (see above comment on LZ4_resetStream_fast() for a definition of "correctly initialized").
+     *  From a high level, the difference is that
+     *  this function initializes the provided state with a call to something like LZ4_resetStream_fast()
+     *  while LZ4_compress_fast_extState() starts with a call to LZ4_resetStream().
+     */
+    LZ4LIB_STATIC_API int LZ4_compress_fast_extState_fastReset(void *state, const char *src, char *dst, int srcSize, int dstCapacity, int acceleration);
+
+    /*! LZ4_attach_dictionary() :
+     *  This is an experimental API that allows
+     *  efficient use of a static dictionary many times.
+     *
+     *  Rather than re-loading the dictionary buffer into a working context before
+     *  each compression, or copying a pre-loaded dictionary's LZ4_stream_t into a
+     *  working LZ4_stream_t, this function introduces a no-copy setup mechanism,
+     *  in which the working stream references the dictionary stream in-place.
+     *
+     *  Several assumptions are made about the state of the dictionary stream.
+     *  Currently, only streams which have been prepared by LZ4_loadDict() should
+     *  be expected to work.
+     *
+     *  Alternatively, the provided dictionaryStream may be NULL,
+     *  in which case any existing dictionary stream is unset.
+     *
+     *  If a dictionary is provided, it replaces any pre-existing stream history.
+     *  The dictionary contents are the only history that can be referenced and
+     *  logically immediately precede the data compressed in the first subsequent
+     *  compression call.
+     *
+     *  The dictionary will only remain attached to the working stream through the
+     *  first compression call, at the end of which it is cleared. The dictionary
+     *  stream (and source buffer) must remain in-place / accessible / unchanged
+     *  through the completion of the first compression call on the stream.
+     */
+    LZ4LIB_STATIC_API void LZ4_attach_dictionary(LZ4_stream_t *workingStream, const LZ4_stream_t *dictionaryStream);
+
+    /*! In-place compression and decompression
+     *
+     * It's possible to have input and output sharing the same buffer,
+     * for highly contrained memory environments.
+     * In both cases, it requires input to lay at the end of the buffer,
+     * and decompression to start at beginning of the buffer.
+     * Buffer size must feature some margin, hence be larger than final size.
+     *
+     * |<------------------------buffer--------------------------------->|
+     *                             |<-----------compressed data--------->|
+     * |<-----------decompressed size------------------>|
+     *                                                  |<----margin---->|
+     *
+     * This technique is more useful for decompression,
+     * since decompressed size is typically larger,
+     * and margin is short.
+     *
+     * In-place decompression will work inside any buffer
+     * which size is >= LZ4_DECOMPRESS_INPLACE_BUFFER_SIZE(decompressedSize).
+     * This presumes that decompressedSize > compressedSize.
+     * Otherwise, it means compression actually expanded data,
+     * and it would be more efficient to store such data with a flag indicating it's not compressed.
+     * This can happen when data is not compressible (already compressed, or encrypted).
+     *
+     * For in-place compression, margin is larger, as it must be able to cope with both
+     * history preservation, requiring input data to remain unmodified up to LZ4_DISTANCE_MAX,
+     * and data expansion, which can happen when input is not compressible.
+     * As a consequence, buffer size requirements are much higher,
+     * and memory savings offered by in-place compression are more limited.
+     *
+     * There are ways to limit this cost for compression :
+     * - Reduce history size, by modifying LZ4_DISTANCE_MAX.
+     *   Note that it is a compile-time constant, so all compressions will apply this limit.
+     *   Lower values will reduce compression ratio, except when input_size < LZ4_DISTANCE_MAX,
+     *   so it's a reasonable trick when inputs are known to be small.
+     * - Require the compressor to deliver a "maximum compressed size".
+     *   This is the `dstCapacity` parameter in `LZ4_compress*()`.
+     *   When this size is < LZ4_COMPRESSBOUND(inputSize), then compression can fail,
+     *   in which case, the return code will be 0 (zero).
+     *   The caller must be ready for these cases to happen,
+     *   and typically design a backup scheme to send data uncompressed.
+     * The combination of both techniques can significantly reduce
+     * the amount of margin required for in-place compression.
+     *
+     * In-place compression can work in any buffer
+     * which size is >= (maxCompressedSize)
+     * with maxCompressedSize == LZ4_COMPRESSBOUND(srcSize) for guaranteed compression success.
+     * LZ4_COMPRESS_INPLACE_BUFFER_SIZE() depends on both maxCompressedSize and LZ4_DISTANCE_MAX,
+     * so it's possible to reduce memory requirements by playing with them.
+     */
+
+#define LZ4_DECOMPRESS_INPLACE_MARGIN(compressedSize) (((compressedSize) >> 8) + 32)
+#define LZ4_DECOMPRESS_INPLACE_BUFFER_SIZE(decompressedSize) ((decompressedSize) + LZ4_DECOMPRESS_INPLACE_MARGIN(decompressedSize)) /**< note: presumes that compressedSize < decompressedSize. note2: margin is overestimated a bit, since it could use compressedSize instead */
+
+#ifndef LZ4_DISTANCE_MAX       /* history window size; can be user-defined at compile time */
+#define LZ4_DISTANCE_MAX 65535 /* set to maximum value by default */
+#endif
+
+#define LZ4_COMPRESS_INPLACE_MARGIN (LZ4_DISTANCE_MAX + 32)                                                     /* LZ4_DISTANCE_MAX can be safely replaced by srcSize when it's smaller */
+#define LZ4_COMPRESS_INPLACE_BUFFER_SIZE(maxCompressedSize) ((maxCompressedSize) + LZ4_COMPRESS_INPLACE_MARGIN) /**< maxCompressedSize is generally LZ4_COMPRESSBOUND(inputSize), but can be set to any lower value, with the risk that compression can fail (return code 0(zero)) */
+
+#endif /* LZ4_STATIC_3504398509 */
+#endif /* LZ4_STATIC_LINKING_ONLY */
+
+#ifndef LZ4_H_98237428734687
+#define LZ4_H_98237428734687
+
+/*-************************************************************
+ *  Private Definitions
+ **************************************************************
+ * Do not use these definitions directly.
+ * They are only exposed to allow static allocation of `LZ4_stream_t` and `LZ4_streamDecode_t`.
+ * Accessing members will expose user code to API and/or ABI break in future versions of the library.
+ **************************************************************/
+#define LZ4_HASHLOG (LZ4_MEMORY_USAGE - 2)
+#define LZ4_HASHTABLESIZE (1 << LZ4_MEMORY_USAGE)
+#define LZ4_HASH_SIZE_U32 (1 << LZ4_HASHLOG) /* required as macro for static allocation */
+
+#if defined(__cplusplus) || (defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
+#include <stdint.h>
+    typedef int8_t LZ4_i8;
+    typedef uint8_t LZ4_byte;
+    typedef uint16_t LZ4_u16;
+    typedef uint32_t LZ4_u32;
+#else
+    typedef signed char LZ4_i8;
+    typedef unsigned char LZ4_byte;
+    typedef unsigned short LZ4_u16;
+    typedef unsigned int LZ4_u32;
+#endif
+
+    typedef struct LZ4_stream_t_internal LZ4_stream_t_internal;
+    struct LZ4_stream_t_internal
+    {
+        LZ4_u32 hashTable[LZ4_HASH_SIZE_U32];
+        LZ4_u32 currentOffset;
+        LZ4_u32 tableType;
+        const LZ4_byte *dictionary;
+        const LZ4_stream_t_internal *dictCtx;
+        LZ4_u32 dictSize;
+    };
+
+    typedef struct
+    {
+        const LZ4_byte *externalDict;
+        size_t extDictSize;
+        const LZ4_byte *prefixEnd;
+        size_t prefixSize;
+    } LZ4_streamDecode_t_internal;
+
+/*! LZ4_stream_t :
+ *  Do not use below internal definitions directly !
+ *  Declare or allocate an LZ4_stream_t instead.
+ *  LZ4_stream_t can also be created using LZ4_createStream(), which is recommended.
+ *  The structure definition can be convenient for static allocation
+ *  (on stack, or as part of larger structure).
+ *  Init this structure with LZ4_initStream() before first use.
+ *  note : only use this definition in association with static linking !
+ *  this definition is not API/ABI safe, and may change in future versions.
+ */
+#define LZ4_STREAMSIZE 16416 /* static size, for inter-version compatibility */
+#define LZ4_STREAMSIZE_VOIDP (LZ4_STREAMSIZE / sizeof(void *))
+    union LZ4_stream_u
+    {
+        void *table[LZ4_STREAMSIZE_VOIDP];
+        LZ4_stream_t_internal internal_donotuse;
+    }; /* previously typedef'd to LZ4_stream_t */
+
+    /*! LZ4_initStream() : v1.9.0+
+     *  An LZ4_stream_t structure must be initialized at least once.
+     *  This is automatically done when invoking LZ4_createStream(),
+     *  but it's not when the structure is simply declared on stack (for example).
+     *
+     *  Use LZ4_initStream() to properly initialize a newly declared LZ4_stream_t.
+     *  It can also initialize any arbitrary buffer of sufficient size,
+     *  and will @return a pointer of proper type upon initialization.
+     *
+     *  Note : initialization fails if size and alignment conditions are not respected.
+     *         In which case, the function will @return NULL.
+     *  Note2: An LZ4_stream_t structure guarantees correct alignment and size.
+     *  Note3: Before v1.9.0, use LZ4_resetStream() instead
+     */
+    LZ4LIB_API LZ4_stream_t *LZ4_initStream(void *buffer, size_t size);
+
+/*! LZ4_streamDecode_t :
+ *  information structure to track an LZ4 stream during decompression.
+ *  init this structure  using LZ4_setStreamDecode() before first use.
+ *  note : only use in association with static linking !
+ *         this definition is not API/ABI safe,
+ *         and may change in a future version !
+ */
+#define LZ4_STREAMDECODESIZE_U64 (4 + ((sizeof(void *) == 16) ? 2 : 0) /*AS-400*/)
+#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U64 * sizeof(unsigned long long))
+    union LZ4_streamDecode_u
+    {
+        unsigned long long table[LZ4_STREAMDECODESIZE_U64];
+        LZ4_streamDecode_t_internal internal_donotuse;
+    }; /* previously typedef'd to LZ4_streamDecode_t */
+
+/*-************************************
+ *  Obsolete Functions
+ **************************************/
+
+/*! Deprecation warnings
+ *
+ *  Deprecated functions make the compiler generate a warning when invoked.
+ *  This is meant to invite users to update their source code.
+ *  Should deprecation warnings be a problem, it is generally possible to disable them,
+ *  typically with -Wno-deprecated-declarations for gcc
+ *  or _CRT_SECURE_NO_WARNINGS in Visual.
+ *
+ *  Another method is to define LZ4_DISABLE_DEPRECATE_WARNINGS
+ *  before including the header file.
+ */
+#ifdef LZ4_DISABLE_DEPRECATE_WARNINGS
+#define LZ4_DEPRECATED(message) /* disable deprecation warnings */
+#else
+#if defined(__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */
+#define LZ4_DEPRECATED(message) [[deprecated(message)]]
+#elif defined(_MSC_VER)
+#define LZ4_DEPRECATED(message) __declspec(deprecated(message))
+#elif defined(__clang__) || (defined(__GNUC__) && (__GNUC__ * 10 + __GNUC_MINOR__ >= 45))
+#define LZ4_DEPRECATED(message) __attribute__((deprecated(message)))
+#elif defined(__GNUC__) && (__GNUC__ * 10 + __GNUC_MINOR__ >= 31)
+#define LZ4_DEPRECATED(message) __attribute__((deprecated))
+#else
+#pragma message("WARNING: LZ4_DEPRECATED needs custom implementation for this compiler")
+#define LZ4_DEPRECATED(message) /* disabled */
+#endif
+#endif /* LZ4_DISABLE_DEPRECATE_WARNINGS */
+
+    /*! Obsolete compression functions (since v1.7.3) */
+    LZ4_DEPRECATED("use LZ4_compress_default() instead")
+    LZ4LIB_API int LZ4_compress(const char *src, char *dest, int srcSize);
+    LZ4_DEPRECATED("use LZ4_compress_default() instead")
+    LZ4LIB_API int LZ4_compress_limitedOutput(const char *src, char *dest, int srcSize, int maxOutputSize);
+    LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead")
+    LZ4LIB_API int LZ4_compress_withState(void *state, const char *source, char *dest, int inputSize);
+    LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead")
+    LZ4LIB_API int LZ4_compress_limitedOutput_withState(void *state, const char *source, char *dest, int inputSize, int maxOutputSize);
+    LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead")
+    LZ4LIB_API int LZ4_compress_continue(LZ4_stream_t *LZ4_streamPtr, const char *source, char *dest, int inputSize);
+    LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead")
+    LZ4LIB_API int LZ4_compress_limitedOutput_continue(LZ4_stream_t *LZ4_streamPtr, const char *source, char *dest, int inputSize, int maxOutputSize);
+
+    /*! Obsolete decompression functions (since v1.8.0) */
+    LZ4_DEPRECATED("use LZ4_decompress_fast() instead")
+    LZ4LIB_API int LZ4_uncompress(const char *source, char *dest, int outputSize);
+    LZ4_DEPRECATED("use LZ4_decompress_safe() instead")
+    LZ4LIB_API int LZ4_uncompress_unknownOutputSize(const char *source, char *dest, int isize, int maxOutputSize);
+
+    /* Obsolete streaming functions (since v1.7.0)
+     * degraded functionality; do not use!
+     *
+     * In order to perform streaming compression, these functions depended on data
+     * that is no longer tracked in the state. They have been preserved as well as
+     * possible: using them will still produce a correct output. However, they don't
+     * actually retain any history between compression calls. The compression ratio
+     * achieved will therefore be no better than compressing each chunk
+     * independently.
+     */
+    LZ4_DEPRECATED("Use LZ4_createStream() instead")
+    LZ4LIB_API void *LZ4_create(char *inputBuffer);
+    LZ4_DEPRECATED("Use LZ4_createStream() instead")
+    LZ4LIB_API int LZ4_sizeofStreamState(void);
+    LZ4_DEPRECATED("Use LZ4_resetStream() instead")
+    LZ4LIB_API int LZ4_resetStreamState(void *state, char *inputBuffer);
+    LZ4_DEPRECATED("Use LZ4_saveDict() instead")
+    LZ4LIB_API char *LZ4_slideInputBuffer(void *state);
+
+    /*! Obsolete streaming decoding functions (since v1.7.0) */
+    LZ4_DEPRECATED("use LZ4_decompress_safe_usingDict() instead")
+    LZ4LIB_API int LZ4_decompress_safe_withPrefix64k(const char *src, char *dst, int compressedSize, int maxDstSize);
+    LZ4_DEPRECATED("use LZ4_decompress_fast_usingDict() instead")
+    LZ4LIB_API int LZ4_decompress_fast_withPrefix64k(const char *src, char *dst, int originalSize);
+
+    /*! Obsolete LZ4_decompress_fast variants (since v1.9.0) :
+     *  These functions used to be faster than LZ4_decompress_safe(),
+     *  but this is no longer the case. They are now slower.
+     *  This is because LZ4_decompress_fast() doesn't know the input size,
+     *  and therefore must progress more cautiously into the input buffer to not read beyond the end of block.
+     *  On top of that `LZ4_decompress_fast()` is not protected vs malformed or malicious inputs, making it a security liability.
+     *  As a consequence, LZ4_decompress_fast() is strongly discouraged, and deprecated.
+     *
+     *  The last remaining LZ4_decompress_fast() specificity is that
+     *  it can decompress a block without knowing its compressed size.
+     *  Such functionality can be achieved in a more secure manner
+     *  by employing LZ4_decompress_safe_partial().
+     *
+     *  Parameters:
+     *  originalSize : is the uncompressed size to regenerate.
+     *                 `dst` must be already allocated, its size must be >= 'originalSize' bytes.
+     * @return : number of bytes read from source buffer (== compressed size).
+     *           The function expects to finish at block's end exactly.
+     *           If the source stream is detected malformed, the function stops decoding and returns a negative result.
+     *  note : LZ4_decompress_fast*() requires originalSize. Thanks to this information, it never writes past the output buffer.
+     *         However, since it doesn't know its 'src' size, it may read an unknown amount of input, past input buffer bounds.
+     *         Also, since match offsets are not validated, match reads from 'src' may underflow too.
+     *         These issues never happen if input (compressed) data is correct.
+     *         But they may happen if input data is invalid (error or intentional tampering).
+     *         As a consequence, use these functions in trusted environments with trusted data **only**.
+     */
+    LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe() instead")
+    LZ4LIB_API int LZ4_decompress_fast(const char *src, char *dst, int originalSize);
+    LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe_continue() instead")
+    LZ4LIB_API int LZ4_decompress_fast_continue(LZ4_streamDecode_t *LZ4_streamDecode, const char *src, char *dst, int originalSize);
+    LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe_usingDict() instead")
+    LZ4LIB_API int LZ4_decompress_fast_usingDict(const char *src, char *dst, int originalSize, const char *dictStart, int dictSize);
+
+    /*! LZ4_resetStream() :
+     *  An LZ4_stream_t structure must be initialized at least once.
+     *  This is done with LZ4_initStream(), or LZ4_resetStream().
+     *  Consider switching to LZ4_initStream(),
+     *  invoking LZ4_resetStream() will trigger deprecation warnings in the future.
+     */
+    LZ4LIB_API void LZ4_resetStream(LZ4_stream_t *streamPtr);
+
+#endif /* LZ4_H_98237428734687 */
+
+#if defined(__cplusplus)
+}
+#endif

kernel/lib/Makefile

@@ -3,10 +3,17 @@ CFLAGS += -I .
 
 kernel_lib_subdirs:= libUI
 
+kernel_lib_objs:= $(shell find ./*.c)
+
 ECHO:
 	@echo "$@"
 
 $(kernel_lib_subdirs): ECHO
 	$(MAKE) -C $@ all CFLAGS="$(CFLAGS)" ASFLAGS="$(ASFLAGS)" PIC="$(PIC)"
 
-all: $(kernel_lib_subdirs)
+$(kernel_lib_objs): ECHO
+	gcc $(CFLAGS) -c $@ -o [email protected]
+
+all: $(kernel_lib_objs) $(kernel_lib_subdirs)
+	@echo $(kernel_lib_objs)
+

kernel/lib/lz4.c

@@ -0,0 +1,3147 @@
+/*
+   LZ4 - Fast LZ compression algorithm
+   Copyright (C) 2011-present, Yann Collet.
+
+   BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are
+   met:
+
+       * Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above
+   copyright notice, this list of conditions and the following disclaimer
+   in the documentation and/or other materials provided with the
+   distribution.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+   You can contact the author at :
+    - LZ4 homepage : http://www.lz4.org
+    - LZ4 source repository : https://github.com/lz4/lz4
+*/
+
+/*-************************************
+ *  Tuning parameters
+ **************************************/
+/*
+ * LZ4_HEAPMODE :
+ * Select how default compression functions will allocate memory for their hash table,
+ * in memory stack (0:default, fastest), or in memory heap (1:requires malloc()).
+ */
+#ifndef LZ4_HEAPMODE
+#define LZ4_HEAPMODE 0
+#endif
+
+/*
+ * LZ4_ACCELERATION_DEFAULT :
+ * Select "acceleration" for LZ4_compress_fast() when parameter value <= 0
+ */
+#define LZ4_ACCELERATION_DEFAULT 1
+/*
+ * LZ4_ACCELERATION_MAX :
+ * Any "acceleration" value higher than this threshold
+ * get treated as LZ4_ACCELERATION_MAX instead (fix #876)
+ */
+#define LZ4_ACCELERATION_MAX 65537
+
+/*-************************************
+ *  CPU Feature Detection
+ **************************************/
+/* LZ4_FORCE_MEMORY_ACCESS
+ * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable.
+ * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal.
+ * The below switch allow to select different access method for improved performance.
+ * Method 0 (default) : use `memcpy()`. Safe and portable.
+ * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable).
+ *            This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`.
+ * Method 2 : direct access. This method is portable but violate C standard.
+ *            It can generate buggy code on targets which assembly generation depends on alignment.
+ *            But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6)
+ * See https://fastcompression.blogspot.fr/2015/08/accessing-unaligned-memory.html for details.
+ * Prefer these methods in priority order (0 > 1 > 2)
+ */
+#ifndef LZ4_FORCE_MEMORY_ACCESS /* can be defined externally */
+#if defined(__GNUC__) && \
+    (defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__))
+#define LZ4_FORCE_MEMORY_ACCESS 2
+#elif (defined(__INTEL_COMPILER) && !defined(_WIN32)) || defined(__GNUC__)
+#define LZ4_FORCE_MEMORY_ACCESS 1
+#endif
+#endif
+
+/*
+ * LZ4_FORCE_SW_BITCOUNT
+ * Define this parameter if your target system or compiler does not support hardware bit count
+ */
+#if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for WinCE doesn't support Hardware bit count */
+#undef LZ4_FORCE_SW_BITCOUNT                 /* avoid double def */
+#define LZ4_FORCE_SW_BITCOUNT
+#endif
+
+/*-************************************
+ *  Dependency
+ **************************************/
+/*
+ * LZ4_SRC_INCLUDED:
+ * Amalgamation flag, whether lz4.c is included
+ */
+#ifndef LZ4_SRC_INCLUDED
+#define LZ4_SRC_INCLUDED 1
+#endif
+
+#ifndef LZ4_STATIC_LINKING_ONLY
+#define LZ4_STATIC_LINKING_ONLY
+#endif
+
+#ifndef LZ4_DISABLE_DEPRECATE_WARNINGS
+#define LZ4_DISABLE_DEPRECATE_WARNINGS /* due to LZ4_decompress_safe_withPrefix64k */
+#endif
+
+#define LZ4_STATIC_LINKING_ONLY /* LZ4_DISTANCE_MAX */
+#include <common/lz4.h>
+#include <common/glib.h>
+/* see also "memory routines" below */
+
+/*-************************************
+ *  Compiler Options
+ **************************************/
+#if defined(_MSC_VER) && (_MSC_VER >= 1400) /* Visual Studio 2005+ */
+#include <intrin.h>                         /* only present in VS2005+ */
+#pragma warning(disable : 4127)             /* disable: C4127: conditional expression is constant */
+#endif                                      /* _MSC_VER */
+
+#ifndef LZ4_FORCE_INLINE
+#ifdef _MSC_VER /* Visual Studio */
+#define LZ4_FORCE_INLINE static __forceinline
+#else
+#if defined(__cplusplus) || defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
+#ifdef __GNUC__
+#define LZ4_FORCE_INLINE static inline __attribute__((always_inline))
+#else
+#define LZ4_FORCE_INLINE static inline
+#endif
+#else
+#define LZ4_FORCE_INLINE static
+#endif /* __STDC_VERSION__ */
+#endif /* _MSC_VER */
+#endif /* LZ4_FORCE_INLINE */
+
+/* LZ4_FORCE_O2 and LZ4_FORCE_INLINE
+ * gcc on ppc64le generates an unrolled SIMDized loop for LZ4_wildCopy8,
+ * together with a simple 8-byte copy loop as a fall-back path.
+ * However, this optimization hurts the decompression speed by >30%,
+ * because the execution does not go to the optimized loop
+ * for typical compressible data, and all of the preamble checks
+ * before going to the fall-back path become useless overhead.
+ * This optimization happens only with the -O3 flag, and -O2 generates
+ * a simple 8-byte copy loop.
+ * With gcc on ppc64le, all of the LZ4_decompress_* and LZ4_wildCopy8
+ * functions are annotated with __attribute__((optimize("O2"))),
+ * and also LZ4_wildCopy8 is forcibly inlined, so that the O2 attribute
+ * of LZ4_wildCopy8 does not affect the compression speed.
+ */
+#if defined(__PPC64__) && defined(__LITTLE_ENDIAN__) && defined(__GNUC__) && !defined(__clang__)
+#define LZ4_FORCE_O2 __attribute__((optimize("O2")))
+#undef LZ4_FORCE_INLINE
+#define LZ4_FORCE_INLINE static __inline __attribute__((optimize("O2"), always_inline))
+#else
+#define LZ4_FORCE_O2
+#endif
+
+#if (defined(__GNUC__) && (__GNUC__ >= 3)) || (defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 800)) || defined(__clang__)
+#define expect(expr, value) (__builtin_expect((expr), (value)))
+#else
+#define expect(expr, value) (expr)
+#endif
+
+#ifndef likely
+#define likely(expr) expect((expr) != 0, 1)
+#endif
+#ifndef unlikely
+#define unlikely(expr) expect((expr) != 0, 0)
+#endif
+
+/* Should the alignment test prove unreliable, for some reason,
+ * it can be disabled by setting LZ4_ALIGN_TEST to 0 */
+#ifndef LZ4_ALIGN_TEST /* can be externally provided */
+#define LZ4_ALIGN_TEST 1
+#endif
+
+/*-************************************
+ *  Memory routines
+ **************************************/
+#ifdef LZ4_USER_MEMORY_FUNCTIONS
+/* memory management functions can be customized by user project.
+ * Below functions must exist somewhere in the Project
+ * and be available at link time */
+void *LZ4_malloc(size_t s);
+void *LZ4_calloc(size_t n, size_t s);
+void LZ4_free(void *p);
+#define ALLOC(s) LZ4_malloc(s)
+#define ALLOC_AND_ZERO(s) LZ4_calloc(1, s)
+#define FREEMEM(p) LZ4_free(p)
+#else
+#include <mm/slab.h> /* malloc, calloc, free */
+#define ALLOC(s) kmalloc(s, 0)
+#define ALLOC_AND_ZERO(s) kzalloc(s, 0)
+#define FREEMEM(p) kfree(p)
+#endif
+
+#include <common/string.h> /* memset, memcpy */
+#define MEM_INIT(p, v, s) memset((p), (v), (s))
+
+/*-************************************
+ *  Common Constants
+ **************************************/
+#define MINMATCH 4
+
+#define WILDCOPYLENGTH 8
+#define LASTLITERALS 5                                             /* see ../doc/lz4_Block_format.md#parsing-restrictions */
+#define MFLIMIT 12                                                 /* see ../doc/lz4_Block_format.md#parsing-restrictions */
+#define MATCH_SAFEGUARD_DISTANCE ((2 * WILDCOPYLENGTH) - MINMATCH) /* ensure it's possible to write 2 x wildcopyLength without overflowing output buffer */
+#define FASTLOOP_SAFE_DISTANCE 64
+static const int LZ4_minLength = (MFLIMIT + 1);
+
+#define KB *(1 << 10)
+#define MB *(1 << 20)
+#define GB *(1U << 30)
+
+#define LZ4_DISTANCE_ABSOLUTE_MAX 65535
+#if (LZ4_DISTANCE_MAX > LZ4_DISTANCE_ABSOLUTE_MAX) /* max supported by LZ4 format */
+#error "LZ4_DISTANCE_MAX is too big : must be <= 65535"
+#endif
+
+#define ML_BITS 4
+#define ML_MASK ((1U << ML_BITS) - 1)
+#define RUN_BITS (8 - ML_BITS)
+#define RUN_MASK ((1U << RUN_BITS) - 1)
+
+/*-************************************
+ *  Error detection
+ **************************************/
+#if defined(LZ4_DEBUG) && (LZ4_DEBUG >= 1)
+#include <assert.h>
+#else
+#ifndef assert
+#define assert(condition) ((void)0)
+#endif
+#endif
+
+#define LZ4_STATIC_ASSERT(c)                     \
+    {                                            \
+        enum                                     \
+        {                                        \
+            LZ4_static_assert = 1 / (int)(!!(c)) \
+        };                                       \
+    } /* use after variable declarations */
+
+#if defined(LZ4_DEBUG) && (LZ4_DEBUG >= 2)
+#include <stdio.h>
+static int g_debuglog_enable = 1;
+#define DEBUGLOG(l, ...)                             \
+    {                                                \
+        if ((g_debuglog_enable) && (l <= LZ4_DEBUG)) \
+        {                                            \
+            fprintf(stderr, __FILE__ ": ");          \
+            fprintf(stderr, __VA_ARGS__);            \
+            fprintf(stderr, " \n");                  \
+        }                                            \
+    }
+#else
+#define DEBUGLOG(l, ...) \
+    {                    \
+    } /* disabled */
+#endif
+
+static int LZ4_isAligned(const void *ptr, size_t alignment)
+{
+    return ((size_t)ptr & (alignment - 1)) == 0;
+}
+
+/*-************************************
+ *  Types
+ **************************************/
+#include <limits.h>
+#if defined(__cplusplus) || (defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
+#include <stdint.h>
+typedef uint8_t BYTE;
+typedef uint16_t U16;
+typedef uint32_t U32;
+typedef int32_t S32;
+typedef uint64_t U64;
+typedef uintptr_t uptrval;
+#else
+#if UINT_MAX != 4294967295UL
+#error "LZ4 code (when not C++ or C99) assumes that sizeof(int) == 4"
+#endif
+typedef unsigned char BYTE;
+typedef unsigned short U16;
+typedef unsigned int U32;
+typedef signed int S32;
+typedef unsigned long long U64;
+typedef size_t uptrval; /* generally true, except OpenVMS-64 */
+#endif
+
+#if defined(__x86_64__)
+typedef U64 reg_t; /* 64-bits in x32 mode */
+#else
+typedef size_t reg_t;   /* 32-bits in x32 mode */
+#endif
+
+typedef enum
+{
+    notLimited = 0,
+    limitedOutput = 1,
+    fillOutput = 2
+} limitedOutput_directive;
+
+/*-************************************
+ *  Reading and writing into memory
+ **************************************/
+
+/**
+ * LZ4 relies on memcpy with a constant size being inlined. In freestanding
+ * environments, the compiler can't assume the implementation of memcpy() is
+ * standard compliant, so it can't apply its specialized memcpy() inlining
+ * logic. When possible, use __builtin_memcpy() to tell the compiler to analyze
+ * memcpy() as if it were standard compliant, so it can inline it in freestanding
+ * environments. This is needed when decompressing the Linux Kernel, for example.
+ */
+#define LZ4_memcpy(dst, src, size) memcpy(dst, src, size)
+
+static unsigned LZ4_isLittleEndian(void)
+{
+    const union
+    {
+        U32 u;
+        BYTE c[4];
+    } one = {1}; /* don't use static : performance detrimental */
+    return one.c[0];
+}
+
+#if defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS == 2)
+/* lie to the compiler about data alignment; use with caution */
+
+static U16 LZ4_read16(const void *memPtr) { return *(const U16 *)memPtr; }
+static U32 LZ4_read32(const void *memPtr) { return *(const U32 *)memPtr; }
+static reg_t LZ4_read_ARCH(const void *memPtr) { return *(const reg_t *)memPtr; }
+
+static void LZ4_write16(void *memPtr, U16 value) { *(U16 *)memPtr = value; }
+static void LZ4_write32(void *memPtr, U32 value) { *(U32 *)memPtr = value; }
+
+#elif defined(LZ4_FORCE_MEMORY_ACCESS) && (LZ4_FORCE_MEMORY_ACCESS == 1)
+
+/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
+/* currently only defined for gcc and icc */
+typedef union
+{
+    U16 u16;
+    U32 u32;
+    reg_t uArch;
+} __attribute__((packed)) unalign;
+
+static U16 LZ4_read16(const void *ptr) { return ((const unalign *)ptr)->u16; }
+static U32 LZ4_read32(const void *ptr) { return ((const unalign *)ptr)->u32; }
+static reg_t LZ4_read_ARCH(const void *ptr) { return ((const unalign *)ptr)->uArch; }
+
+static void LZ4_write16(void *memPtr, U16 value) { ((unalign *)memPtr)->u16 = value; }
+static void LZ4_write32(void *memPtr, U32 value) { ((unalign *)memPtr)->u32 = value; }
+
+#else /* safe and portable access using memcpy() */
+
+static U16 LZ4_read16(const void *memPtr)
+{
+    U16 val;
+    LZ4_memcpy(&val, memPtr, sizeof(val));
+    return val;
+}
+
+static U32 LZ4_read32(const void *memPtr)
+{
+    U32 val;
+    LZ4_memcpy(&val, memPtr, sizeof(val));
+    return val;
+}
+
+static reg_t LZ4_read_ARCH(const void *memPtr)
+{
+    reg_t val;
+    LZ4_memcpy(&val, memPtr, sizeof(val));
+    return val;
+}
+
+static void LZ4_write16(void *memPtr, U16 value)
+{
+    LZ4_memcpy(memPtr, &value, sizeof(value));
+}
+
+static void LZ4_write32(void *memPtr, U32 value)
+{
+    LZ4_memcpy(memPtr, &value, sizeof(value));
+}
+
+#endif /* LZ4_FORCE_MEMORY_ACCESS */
+
+static U16 LZ4_readLE16(const void *memPtr)
+{
+    if (LZ4_isLittleEndian())
+    {
+        return LZ4_read16(memPtr);
+    }
+    else
+    {
+        const BYTE *p = (const BYTE *)memPtr;
+        return (U16)((U16)p[0] + (p[1] << 8));
+    }
+}
+
+static void LZ4_writeLE16(void *memPtr, U16 value)
+{
+    if (LZ4_isLittleEndian())
+    {
+        LZ4_write16(memPtr, value);
+    }
+    else
+    {
+        BYTE *p = (BYTE *)memPtr;
+        p[0] = (BYTE)value;
+        p[1] = (BYTE)(value >> 8);
+    }
+}
+
+/* customized variant of memcpy, which can overwrite up to 8 bytes beyond dstEnd */
+LZ4_FORCE_INLINE
+void LZ4_wildCopy8(void *dstPtr, const void *srcPtr, void *dstEnd)
+{
+    BYTE *d = (BYTE *)dstPtr;
+    const BYTE *s = (const BYTE *)srcPtr;
+    BYTE *const e = (BYTE *)dstEnd;
+
+    do
+    {
+        LZ4_memcpy(d, s, 8);
+        d += 8;
+        s += 8;
+    } while (d < e);
+}
+
+static const unsigned inc32table[8] = {0, 1, 2, 1, 0, 4, 4, 4};
+static const int dec64table[8] = {0, 0, 0, -1, -4, 1, 2, 3};
+
+#ifndef LZ4_FAST_DEC_LOOP
+#if defined __i386__ || defined _M_IX86 || defined __x86_64__ || defined _M_X64
+#define LZ4_FAST_DEC_LOOP 1
+#elif defined(__aarch64__) && !defined(__clang__)
+/* On aarch64, we disable this optimization for clang because on certain
+ * mobile chipsets, performance is reduced with clang. For information
+ * refer to https://github.com/lz4/lz4/pull/707 */
+#define LZ4_FAST_DEC_LOOP 1
+#else
+#define LZ4_FAST_DEC_LOOP 0
+#endif
+#endif
+
+#if LZ4_FAST_DEC_LOOP
+
+LZ4_FORCE_INLINE void
+LZ4_memcpy_using_offset_base(BYTE *dstPtr, const BYTE *srcPtr, BYTE *dstEnd, const size_t offset)
+{
+    assert(srcPtr + offset == dstPtr);
+    if (offset < 8)
+    {
+        LZ4_write32(dstPtr, 0); /* silence an msan warning when offset==0 */
+        dstPtr[0] = srcPtr[0];
+        dstPtr[1] = srcPtr[1];
+        dstPtr[2] = srcPtr[2];
+        dstPtr[3] = srcPtr[3];
+        srcPtr += inc32table[offset];
+        LZ4_memcpy(dstPtr + 4, srcPtr, 4);
+        srcPtr -= dec64table[offset];
+        dstPtr += 8;
+    }
+    else
+    {
+        LZ4_memcpy(dstPtr, srcPtr, 8);
+        dstPtr += 8;
+        srcPtr += 8;
+    }
+
+    LZ4_wildCopy8(dstPtr, srcPtr, dstEnd);
+}
+
+/* customized variant of memcpy, which can overwrite up to 32 bytes beyond dstEnd
+ * this version copies two times 16 bytes (instead of one time 32 bytes)
+ * because it must be compatible with offsets >= 16. */
+LZ4_FORCE_INLINE void
+LZ4_wildCopy32(void *dstPtr, const void *srcPtr, void *dstEnd)
+{
+    BYTE *d = (BYTE *)dstPtr;
+    const BYTE *s = (const BYTE *)srcPtr;
+    BYTE *const e = (BYTE *)dstEnd;
+
+    do
+    {
+        LZ4_memcpy(d, s, 16);
+        LZ4_memcpy(d + 16, s + 16, 16);
+        d += 32;
+        s += 32;
+    } while (d < e);
+}
+
+/* LZ4_memcpy_using_offset()  presumes :
+ * - dstEnd >= dstPtr + MINMATCH
+ * - there is at least 8 bytes available to write after dstEnd */
+LZ4_FORCE_INLINE void
+LZ4_memcpy_using_offset(BYTE *dstPtr, const BYTE *srcPtr, BYTE *dstEnd, const size_t offset)
+{
+    BYTE v[8];
+
+    assert(dstEnd >= dstPtr + MINMATCH);
+
+    switch (offset)
+    {
+    case 1:
+        MEM_INIT(v, *srcPtr, 8);
+        break;
+    case 2:
+        LZ4_memcpy(v, srcPtr, 2);
+        LZ4_memcpy(&v[2], srcPtr, 2);
+        LZ4_memcpy(&v[4], v, 4);
+        break;
+    case 4:
+        LZ4_memcpy(v, srcPtr, 4);
+        LZ4_memcpy(&v[4], srcPtr, 4);
+        break;
+    default:
+        LZ4_memcpy_using_offset_base(dstPtr, srcPtr, dstEnd, offset);
+        return;
+    }
+
+    LZ4_memcpy(dstPtr, v, 8);
+    dstPtr += 8;
+    while (dstPtr < dstEnd)
+    {
+        LZ4_memcpy(dstPtr, v, 8);
+        dstPtr += 8;
+    }
+}
+#endif
+
+/*-************************************
+ *  Common functions
+ **************************************/
+static unsigned LZ4_NbCommonBytes(reg_t val)
+{
+    assert(val != 0);
+    if (LZ4_isLittleEndian())
+    {
+        if (sizeof(val) == 8)
+        {
+#if defined(_MSC_VER) && (_MSC_VER >= 1800) && defined(_M_AMD64) && !defined(LZ4_FORCE_SW_BITCOUNT)
+            /* x64 CPUS without BMI support interpret `TZCNT` as `REP BSF` */
+            return (unsigned)_tzcnt_u64(val) >> 3;
+#elif defined(_MSC_VER) && defined(_WIN64) && !defined(LZ4_FORCE_SW_BITCOUNT)
+            unsigned long r = 0;
+            _BitScanForward64(&r, (U64)val);
+            return (unsigned)r >> 3;
+#elif (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) ||                                \
+                                                    ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \
+    !defined(LZ4_FORCE_SW_BITCOUNT)
+            return (unsigned)__builtin_ctzll((U64)val) >> 3;
+#else
+            const U64 m = 0x0101010101010101ULL;
+            val ^= val - 1;
+            return (unsigned)(((U64)((val & (m - 1)) * m)) >> 56);
+#endif
+        }
+        else /* 32 bits */
+        {
+#if defined(_MSC_VER) && (_MSC_VER >= 1400) && !defined(LZ4_FORCE_SW_BITCOUNT)
+            unsigned long r;
+            _BitScanForward(&r, (U32)val);
+            return (unsigned)r >> 3;
+#elif (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) ||                                \
+                                                    ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \
+    !defined(__TINYC__) && !defined(LZ4_FORCE_SW_BITCOUNT)
+            return (unsigned)__builtin_ctz((U32)val) >> 3;
+#else
+            const U32 m = 0x01010101;
+            return (unsigned)((((val - 1) ^ val) & (m - 1)) * m) >> 24;
+#endif
+        }
+    }
+    else /* Big Endian CPU */
+    {
+        if (sizeof(val) == 8)
+        {
+#if (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) ||                                \
+                                                  ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \
+    !defined(__TINYC__) && !defined(LZ4_FORCE_SW_BITCOUNT)
+            return (unsigned)__builtin_clzll((U64)val) >> 3;
+#else
+#if 1
+            /* this method is probably faster,
+             * but adds a 128 bytes lookup table */
+            static const unsigned char ctz7_tab[128] = {
+                7,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                3,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                4,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                3,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                5,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                3,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                4,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                3,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                6,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                3,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                4,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                3,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                5,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                3,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                4,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+                3,
+                0,
+                1,
+                0,
+                2,
+                0,
+                1,
+                0,
+            };
+            U64 const mask = 0x0101010101010101ULL;
+            U64 const t = (((val >> 8) - mask) | val) & mask;
+            return ctz7_tab[(t * 0x0080402010080402ULL) >> 57];
+#else
+            /* this method doesn't consume memory space like the previous one,
+             * but it contains several branches,
+             * that may end up slowing execution */
+            static const U32 by32 = sizeof(val) * 4; /* 32 on 64 bits (goal), 16 on 32 bits.
+             Just to avoid some static analyzer complaining about shift by 32 on 32-bits target.
+             Note that this code path is never triggered in 32-bits mode. */
+            unsigned r;
+            if (!(val >> by32))
+            {
+                r = 4;
+            }
+            else
+            {
+                r = 0;
+                val >>= by32;
+            }
+            if (!(val >> 16))
+            {
+                r += 2;
+                val >>= 8;
+            }
+            else
+            {
+                val >>= 24;
+            }
+            r += (!val);
+            return r;
+#endif
+#endif
+        }
+        else /* 32 bits */
+        {
+#if (defined(__clang__) || (defined(__GNUC__) && ((__GNUC__ > 3) ||                                \
+                                                  ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4))))) && \
+    !defined(LZ4_FORCE_SW_BITCOUNT)
+            return (unsigned)__builtin_clz((U32)val) >> 3;
+#else
+            val >>= 8;
+            val = ((((val + 0x00FFFF00) | 0x00FFFFFF) + val) |
+                   (val + 0x00FF0000)) >>
+                  24;
+            return (unsigned)val ^ 3;
+#endif
+        }
+    }
+}
+
+#define STEPSIZE sizeof(reg_t)
+LZ4_FORCE_INLINE
+unsigned LZ4_count(const BYTE *pIn, const BYTE *pMatch, const BYTE *pInLimit)
+{
+    const BYTE *const pStart = pIn;
+
+    if (likely(pIn < pInLimit - (STEPSIZE - 1)))
+    {
+        reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
+        if (!diff)
+        {
+            pIn += STEPSIZE;
+            pMatch += STEPSIZE;
+        }
+        else
+        {
+            return LZ4_NbCommonBytes(diff);
+        }
+    }
+
+    while (likely(pIn < pInLimit - (STEPSIZE - 1)))
+    {
+        reg_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
+        if (!diff)
+        {
+            pIn += STEPSIZE;
+            pMatch += STEPSIZE;
+            continue;
+        }
+        pIn += LZ4_NbCommonBytes(diff);
+        return (unsigned)(pIn - pStart);
+    }
+
+    if ((STEPSIZE == 8) && (pIn < (pInLimit - 3)) && (LZ4_read32(pMatch) == LZ4_read32(pIn)))
+    {
+        pIn += 4;
+        pMatch += 4;
+    }
+    if ((pIn < (pInLimit - 1)) && (LZ4_read16(pMatch) == LZ4_read16(pIn)))
+    {
+        pIn += 2;
+        pMatch += 2;
+    }
+    if ((pIn < pInLimit) && (*pMatch == *pIn))
+        pIn++;
+    return (unsigned)(pIn - pStart);
+}
+
+#ifndef LZ4_COMMONDEFS_ONLY
+/*-************************************
+ *  Local Constants
+ **************************************/
+static const int LZ4_64Klimit = ((64 KB) + (MFLIMIT - 1));
+static const U32 LZ4_skipTrigger = 6; /* Increase this value ==> compression run slower on incompressible data */
+
+/*-************************************
+ *  Local Structures and types
+ **************************************/
+typedef enum
+{
+    clearedTable = 0,
+    byPtr,
+    byU32,
+    byU16
+} tableType_t;
+
+/**
+ * This enum distinguishes several different modes of accessing previous
+ * content in the stream.
+ *
+ * - noDict        : There is no preceding content.
+ * - withPrefix64k : Table entries up to ctx->dictSize before the current blob
+ *                   blob being compressed are valid and refer to the preceding
+ *                   content (of length ctx->dictSize), which is available
+ *                   contiguously preceding in memory the content currently
+ *                   being compressed.
+ * - usingExtDict  : Like withPrefix64k, but the preceding content is somewhere
+ *                   else in memory, starting at ctx->dictionary with length
+ *                   ctx->dictSize.
+ * - usingDictCtx  : Like usingExtDict, but everything concerning the preceding
+ *                   content is in a separate context, pointed to by
+ *                   ctx->dictCtx. ctx->dictionary, ctx->dictSize, and table
+ *                   entries in the current context that refer to positions
+ *                   preceding the beginning of the current compression are
+ *                   ignored. Instead, ctx->dictCtx->dictionary and ctx->dictCtx
+ *                   ->dictSize describe the location and size of the preceding
+ *                   content, and matches are found by looking in the ctx
+ *                   ->dictCtx->hashTable.
+ */
+typedef enum
+{
+    noDict = 0,
+    withPrefix64k,
+    usingExtDict,
+    usingDictCtx
+} dict_directive;
+typedef enum
+{
+    noDictIssue = 0,
+    dictSmall
+} dictIssue_directive;
+
+/*-************************************
+ *  Local Utils
+ **************************************/
+int LZ4_versionNumber(void) { return LZ4_VERSION_NUMBER; }
+const char *LZ4_versionString(void) { return LZ4_VERSION_STRING; }
+int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); }
+int LZ4_sizeofState(void) { return LZ4_STREAMSIZE; }
+
+/*-************************************
+ *  Internal Definitions used in Tests
+ **************************************/
+#if defined(__cplusplus)
+extern "C"
+{
+#endif
+
+    int LZ4_compress_forceExtDict(LZ4_stream_t *LZ4_dict, const char *source, char *dest, int srcSize);
+
+    int LZ4_decompress_safe_forceExtDict(const char *source, char *dest,
+                                         int compressedSize, int maxOutputSize,
+                                         const void *dictStart, size_t dictSize);
+
+#if defined(__cplusplus)
+}
+#endif
+
+/*-******************************
+ *  Compression functions
+ ********************************/
+LZ4_FORCE_INLINE U32 LZ4_hash4(U32 sequence, tableType_t const tableType)
+{
+    if (tableType == byU16)
+        return ((sequence * 2654435761U) >> ((MINMATCH * 8) - (LZ4_HASHLOG + 1)));
+    else
+        return ((sequence * 2654435761U) >> ((MINMATCH * 8) - LZ4_HASHLOG));
+}
+
+LZ4_FORCE_INLINE U32 LZ4_hash5(U64 sequence, tableType_t const tableType)
+{
+    const U32 hashLog = (tableType == byU16) ? LZ4_HASHLOG + 1 : LZ4_HASHLOG;
+    if (LZ4_isLittleEndian())
+    {
+        const U64 prime5bytes = 889523592379ULL;
+        return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog));
+    }
+    else
+    {
+        const U64 prime8bytes = 11400714785074694791ULL;
+        return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog));
+    }
+}
+
+LZ4_FORCE_INLINE U32 LZ4_hashPosition(const void *const p, tableType_t const tableType)
+{
+    if ((sizeof(reg_t) == 8) && (tableType != byU16))
+        return LZ4_hash5(LZ4_read_ARCH(p), tableType);
+    return LZ4_hash4(LZ4_read32(p), tableType);
+}
+
+LZ4_FORCE_INLINE void LZ4_clearHash(U32 h, void *tableBase, tableType_t const tableType)
+{
+    switch (tableType)
+    {
+    default: /* fallthrough */
+    case clearedTable:
+    { /* illegal! */
+        assert(0);
+        return;
+    }
+    case byPtr:
+    {
+        const BYTE **hashTable = (const BYTE **)tableBase;
+        hashTable[h] = NULL;
+        return;
+    }
+    case byU32:
+    {
+        U32 *hashTable = (U32 *)tableBase;
+        hashTable[h] = 0;
+        return;
+    }
+    case byU16:
+    {
+        U16 *hashTable = (U16 *)tableBase;
+        hashTable[h] = 0;
+        return;
+    }
+    }
+}
+
+LZ4_FORCE_INLINE void LZ4_putIndexOnHash(U32 idx, U32 h, void *tableBase, tableType_t const tableType)
+{
+    switch (tableType)
+    {
+    default:           /* fallthrough */
+    case clearedTable: /* fallthrough */
+    case byPtr:
+    { /* illegal! */
+        assert(0);
+        return;
+    }
+    case byU32:
+    {
+        U32 *hashTable = (U32 *)tableBase;
+        hashTable[h] = idx;
+        return;
+    }
+    case byU16:
+    {
+        U16 *hashTable = (U16 *)tableBase;
+        assert(idx < 65536);
+        hashTable[h] = (U16)idx;
+        return;
+    }
+    }
+}
+
+LZ4_FORCE_INLINE void LZ4_putPositionOnHash(const BYTE *p, U32 h,
+                                            void *tableBase, tableType_t const tableType,
+                                            const BYTE *srcBase)
+{
+    switch (tableType)
+    {
+    case clearedTable:
+    { /* illegal! */
+        assert(0);
+        return;
+    }
+    case byPtr:
+    {
+        const BYTE **hashTable = (const BYTE **)tableBase;
+        hashTable[h] = p;
+        return;
+    }
+    case byU32:
+    {
+        U32 *hashTable = (U32 *)tableBase;
+        hashTable[h] = (U32)(p - srcBase);
+        return;
+    }
+    case byU16:
+    {
+        U16 *hashTable = (U16 *)tableBase;
+        hashTable[h] = (U16)(p - srcBase);
+        return;
+    }
+    }
+}
+
+LZ4_FORCE_INLINE void LZ4_putPosition(const BYTE *p, void *tableBase, tableType_t tableType, const BYTE *srcBase)
+{
+    U32 const h = LZ4_hashPosition(p, tableType);
+    LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
+}
+
+/* LZ4_getIndexOnHash() :
+ * Index of match position registered in hash table.
+ * hash position must be calculated by using base+index, or dictBase+index.
+ * Assumption 1 : only valid if tableType == byU32 or byU16.
+ * Assumption 2 : h is presumed valid (within limits of hash table)
+ */
+LZ4_FORCE_INLINE U32 LZ4_getIndexOnHash(U32 h, const void *tableBase, tableType_t tableType)
+{
+    LZ4_STATIC_ASSERT(LZ4_MEMORY_USAGE > 2);
+    if (tableType == byU32)
+    {
+        const U32 *const hashTable = (const U32 *)tableBase;
+        assert(h < (1U << (LZ4_MEMORY_USAGE - 2)));
+        return hashTable[h];
+    }
+    if (tableType == byU16)
+    {
+        const U16 *const hashTable = (const U16 *)tableBase;
+        assert(h < (1U << (LZ4_MEMORY_USAGE - 1)));
+        return hashTable[h];
+    }
+    assert(0);
+    return 0; /* forbidden case */
+}
+
+static const BYTE *LZ4_getPositionOnHash(U32 h, const void *tableBase, tableType_t tableType, const BYTE *srcBase)
+{
+    if (tableType == byPtr)
+    {
+        const BYTE *const *hashTable = (const BYTE *const *)tableBase;
+        return hashTable[h];
+    }
+    if (tableType == byU32)
+    {
+        const U32 *const hashTable = (const U32 *)tableBase;
+        return hashTable[h] + srcBase;
+    }
+    {
+        const U16 *const hashTable = (const U16 *)tableBase;
+        return hashTable[h] + srcBase;
+    } /* default, to ensure a return */
+}
+
+LZ4_FORCE_INLINE const BYTE *
+LZ4_getPosition(const BYTE *p,
+                const void *tableBase, tableType_t tableType,
+                const BYTE *srcBase)
+{
+    U32 const h = LZ4_hashPosition(p, tableType);
+    return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
+}
+
+LZ4_FORCE_INLINE void
+LZ4_prepareTable(LZ4_stream_t_internal *const cctx,
+                 const int inputSize,
+                 const tableType_t tableType)
+{
+    /* If the table hasn't been used, it's guaranteed to be zeroed out, and is
+     * therefore safe to use no matter what mode we're in. Otherwise, we figure
+     * out if it's safe to leave as is or whether it needs to be reset.
+     */
+    if ((tableType_t)cctx->tableType != clearedTable)
+    {
+        assert(inputSize >= 0);
+        if ((tableType_t)cctx->tableType != tableType || ((tableType == byU16) && cctx->currentOffset + (unsigned)inputSize >= 0xFFFFU) || ((tableType == byU32) && cctx->currentOffset > 1 GB) || tableType == byPtr || inputSize >= 4 KB)
+        {
+            DEBUGLOG(4, "LZ4_prepareTable: Resetting table in %p", cctx);
+            MEM_INIT(cctx->hashTable, 0, LZ4_HASHTABLESIZE);
+            cctx->currentOffset = 0;
+            cctx->tableType = (U32)clearedTable;
+        }
+        else
+        {
+            DEBUGLOG(4, "LZ4_prepareTable: Re-use hash table (no reset)");
+        }
+    }
+
+    /* Adding a gap, so all previous entries are > LZ4_DISTANCE_MAX back, is faster
+     * than compressing without a gap. However, compressing with
+     * currentOffset == 0 is faster still, so we preserve that case.
+     */
+    if (cctx->currentOffset != 0 && tableType == byU32)
+    {
+        DEBUGLOG(5, "LZ4_prepareTable: adding 64KB to currentOffset");
+        cctx->currentOffset += 64 KB;
+    }
+
+    /* Finally, clear history */
+    cctx->dictCtx = NULL;
+    cctx->dictionary = NULL;
+    cctx->dictSize = 0;
+}
+
+/** LZ4_compress_generic() :
+ *  inlined, to ensure branches are decided at compilation time.
+ *  Presumed already validated at this stage:
+ *  - source != NULL
+ *  - inputSize > 0
+ */
+LZ4_FORCE_INLINE int LZ4_compress_generic_validated(
+    LZ4_stream_t_internal *const cctx,
+    const char *const source,
+    char *const dest,
+    const int inputSize,
+    int *inputConsumed, /* only written when outputDirective == fillOutput */
+    const int maxOutputSize,
+    const limitedOutput_directive outputDirective,
+    const tableType_t tableType,
+    const dict_directive dictDirective,
+    const dictIssue_directive dictIssue,
+    const int acceleration)
+{
+    int result;
+    const BYTE *ip = (const BYTE *)source;
+
+    U32 const startIndex = cctx->currentOffset;
+    const BYTE *base = (const BYTE *)source - startIndex;
+    const BYTE *lowLimit;
+
+    const LZ4_stream_t_internal *dictCtx = (const LZ4_stream_t_internal *)cctx->dictCtx;
+    const BYTE *const dictionary =
+        dictDirective == usingDictCtx ? dictCtx->dictionary : cctx->dictionary;
+    const U32 dictSize =
+        dictDirective == usingDictCtx ? dictCtx->dictSize : cctx->dictSize;
+    const U32 dictDelta = (dictDirective == usingDictCtx) ? startIndex - dictCtx->currentOffset : 0; /* make indexes in dictCtx comparable with index in current context */
+
+    int const maybe_extMem = (dictDirective == usingExtDict) || (dictDirective == usingDictCtx);
+    U32 const prefixIdxLimit = startIndex - dictSize; /* used when dictDirective == dictSmall */
+    const BYTE *const dictEnd = dictionary ? dictionary + dictSize : dictionary;
+    const BYTE *anchor = (const BYTE *)source;
+    const BYTE *const iend = ip + inputSize;
+    const BYTE *const mflimitPlusOne = iend - MFLIMIT + 1;
+    const BYTE *const matchlimit = iend - LASTLITERALS;
+
+    /* the dictCtx currentOffset is indexed on the start of the dictionary,
+     * while a dictionary in the current context precedes the currentOffset */
+    const BYTE *dictBase = !dictionary ? NULL : (dictDirective == usingDictCtx) ? dictionary + dictSize - dictCtx->currentOffset
+                                                                                : dictionary + dictSize - startIndex;
+
+    BYTE *op = (BYTE *)dest;
+    BYTE *const olimit = op + maxOutputSize;
+
+    U32 offset = 0;
+    U32 forwardH;
+
+    DEBUGLOG(5, "LZ4_compress_generic_validated: srcSize=%i, tableType=%u", inputSize, tableType);
+    assert(ip != NULL);
+    /* If init conditions are not met, we don't have to mark stream
+     * as having dirty context, since no action was taken yet */
+    if (outputDirective == fillOutput && maxOutputSize < 1)
+    {
+        return 0;
+    } /* Impossible to store anything */
+    if ((tableType == byU16) && (inputSize >= LZ4_64Klimit))
+    {
+        return 0;
+    } /* Size too large (not within 64K limit) */
+    if (tableType == byPtr)
+        assert(dictDirective == noDict); /* only supported use case with byPtr */
+    assert(acceleration >= 1);
+
+    lowLimit = (const BYTE *)source - (dictDirective == withPrefix64k ? dictSize : 0);
+
+    /* Update context state */
+    if (dictDirective == usingDictCtx)
+    {
+        /* Subsequent linked blocks can't use the dictionary. */
+        /* Instead, they use the block we just compressed. */
+        cctx->dictCtx = NULL;
+        cctx->dictSize = (U32)inputSize;
+    }
+    else
+    {
+        cctx->dictSize += (U32)inputSize;
+    }
+    cctx->currentOffset += (U32)inputSize;
+    cctx->tableType = (U32)tableType;
+
+    if (inputSize < LZ4_minLength)
+        goto _last_literals; /* Input too small, no compression (all literals) */
+
+    /* First Byte */
+    LZ4_putPosition(ip, cctx->hashTable, tableType, base);
+    ip++;
+    forwardH = LZ4_hashPosition(ip, tableType);
+
+    /* Main Loop */
+    for (;;)
+    {
+        const BYTE *match;
+        BYTE *token;
+        const BYTE *filledIp;
+
+        /* Find a match */
+        if (tableType == byPtr)
+        {
+            const BYTE *forwardIp = ip;
+            int step = 1;
+            int searchMatchNb = acceleration << LZ4_skipTrigger;
+            do
+            {
+                U32 const h = forwardH;
+                ip = forwardIp;
+                forwardIp += step;
+                step = (searchMatchNb++ >> LZ4_skipTrigger);
+
+                if (unlikely(forwardIp > mflimitPlusOne))
+                    goto _last_literals;
+                assert(ip < mflimitPlusOne);
+
+                match = LZ4_getPositionOnHash(h, cctx->hashTable, tableType, base);
+                forwardH = LZ4_hashPosition(forwardIp, tableType);
+                LZ4_putPositionOnHash(ip, h, cctx->hashTable, tableType, base);
+
+            } while ((match + LZ4_DISTANCE_MAX < ip) || (LZ4_read32(match) != LZ4_read32(ip)));
+        }
+        else
+        { /* byU32, byU16 */
+
+            const BYTE *forwardIp = ip;
+            int step = 1;
+            int searchMatchNb = acceleration << LZ4_skipTrigger;
+            do
+            {
+                U32 const h = forwardH;
+                U32 const current = (U32)(forwardIp - base);
+                U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType);
+                assert(matchIndex <= current);
+                assert(forwardIp - base < (ptrdiff_t)(2 GB - 1));
+                ip = forwardIp;
+                forwardIp += step;
+                step = (searchMatchNb++ >> LZ4_skipTrigger);
+
+                if (unlikely(forwardIp > mflimitPlusOne))
+                    goto _last_literals;
+                assert(ip < mflimitPlusOne);
+
+                if (dictDirective == usingDictCtx)
+                {
+                    if (matchIndex < startIndex)
+                    {
+                        /* there was no match, try the dictionary */
+                        assert(tableType == byU32);
+                        matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32);
+                        match = dictBase + matchIndex;
+                        matchIndex += dictDelta; /* make dictCtx index comparable with current context */
+                        lowLimit = dictionary;
+                    }
+                    else
+                    {
+                        match = base + matchIndex;
+                        lowLimit = (const BYTE *)source;
+                    }
+                }
+                else if (dictDirective == usingExtDict)
+                {
+                    if (matchIndex < startIndex)
+                    {
+                        DEBUGLOG(7, "extDict candidate: matchIndex=%5u  <  startIndex=%5u", matchIndex, startIndex);
+                        assert(startIndex - matchIndex >= MINMATCH);
+                        match = dictBase + matchIndex;
+                        lowLimit = dictionary;
+                    }
+                    else
+                    {
+                        match = base + matchIndex;
+                        lowLimit = (const BYTE *)source;
+                    }
+                }
+                else
+                { /* single continuous memory segment */
+                    match = base + matchIndex;
+                }
+                forwardH = LZ4_hashPosition(forwardIp, tableType);
+                LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType);
+
+                DEBUGLOG(7, "candidate at pos=%u  (offset=%u \n", matchIndex, current - matchIndex);
+                if ((dictIssue == dictSmall) && (matchIndex < prefixIdxLimit))
+                {
+                    continue;
+                } /* match outside of valid area */
+                assert(matchIndex < current);
+                if (((tableType != byU16) || (LZ4_DISTANCE_MAX < LZ4_DISTANCE_ABSOLUTE_MAX)) && (matchIndex + LZ4_DISTANCE_MAX < current))
+                {
+                    continue;
+                }                                                   /* too far */
+                assert((current - matchIndex) <= LZ4_DISTANCE_MAX); /* match now expected within distance */
+
+                if (LZ4_read32(match) == LZ4_read32(ip))
+                {
+                    if (maybe_extMem)
+                        offset = current - matchIndex;
+                    break; /* match found */
+                }
+
+            } while (1);
+        }
+
+        /* Catch up */
+        filledIp = ip;
+        while (((ip > anchor) & (match > lowLimit)) && (unlikely(ip[-1] == match[-1])))
+        {
+            ip--;
+            match--;
+        }
+
+        /* Encode Literals */
+        {
+            unsigned const litLength = (unsigned)(ip - anchor);
+            token = op++;
+            if ((outputDirective == limitedOutput) && /* Check output buffer overflow */
+                (unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength / 255) > olimit)))
+            {
+                return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */
+            }
+            if ((outputDirective == fillOutput) &&
+                (unlikely(op + (litLength + 240) / 255 /* litlen */ + litLength /* literals */ + 2 /* offset */ + 1 /* token */ + MFLIMIT - MINMATCH /* min last literals so last match is <= end - MFLIMIT */ > olimit)))
+            {
+                op--;
+                goto _last_literals;
+            }
+            if (litLength >= RUN_MASK)
+            {
+                int len = (int)(litLength - RUN_MASK);
+                *token = (RUN_MASK << ML_BITS);
+                for (; len >= 255; len -= 255)
+                    *op++ = 255;
+                *op++ = (BYTE)len;
+            }
+            else
+                *token = (BYTE)(litLength << ML_BITS);
+
+            /* Copy Literals */
+            LZ4_wildCopy8(op, anchor, op + litLength);
+            op += litLength;
+            DEBUGLOG(6, "seq.start:%i, literals=%u, match.start:%i",
+                     (int)(anchor - (const BYTE *)source), litLength, (int)(ip - (const BYTE *)source));
+        }
+
+    _next_match:
+        /* at this stage, the following variables must be correctly set :
+         * - ip : at start of LZ operation
+         * - match : at start of previous pattern occurence; can be within current prefix, or within extDict
+         * - offset : if maybe_ext_memSegment==1 (constant)
+         * - lowLimit : must be == dictionary to mean "match is within extDict"; must be == source otherwise
+         * - token and *token : position to write 4-bits for match length; higher 4-bits for literal length supposed already written
+         */
+
+        if ((outputDirective == fillOutput) &&
+            (op + 2 /* offset */ + 1 /* token */ + MFLIMIT - MINMATCH /* min last literals so last match is <= end - MFLIMIT */ > olimit))
+        {
+            /* the match was too close to the end, rewind and go to last literals */
+            op = token;
+            goto _last_literals;
+        }
+
+        /* Encode Offset */
+        if (maybe_extMem)
+        { /* static test */
+            DEBUGLOG(6, "             with offset=%u  (ext if > %i)", offset, (int)(ip - (const BYTE *)source));
+            assert(offset <= LZ4_DISTANCE_MAX && offset > 0);
+            LZ4_writeLE16(op, (U16)offset);
+            op += 2;
+        }
+        else
+        {
+            DEBUGLOG(6, "             with offset=%u  (same segment)", (U32)(ip - match));
+            assert(ip - match <= LZ4_DISTANCE_MAX);
+            LZ4_writeLE16(op, (U16)(ip - match));
+            op += 2;
+        }
+
+        /* Encode MatchLength */
+        {
+            unsigned matchCode;
+
+            if ((dictDirective == usingExtDict || dictDirective == usingDictCtx) && (lowLimit == dictionary) /* match within extDict */)
+            {
+                const BYTE *limit = ip + (dictEnd - match);
+                assert(dictEnd > match);
+                if (limit > matchlimit)
+                    limit = matchlimit;
+                matchCode = LZ4_count(ip + MINMATCH, match + MINMATCH, limit);
+                ip += (size_t)matchCode + MINMATCH;
+                if (ip == limit)
+                {
+                    unsigned const more = LZ4_count(limit, (const BYTE *)source, matchlimit);
+                    matchCode += more;
+                    ip += more;
+                }
+                DEBUGLOG(6, "             with matchLength=%u starting in extDict", matchCode + MINMATCH);
+            }
+            else
+            {
+                matchCode = LZ4_count(ip + MINMATCH, match + MINMATCH, matchlimit);
+                ip += (size_t)matchCode + MINMATCH;
+                DEBUGLOG(6, "             with matchLength=%u", matchCode + MINMATCH);
+            }
+
+            if ((outputDirective) && /* Check output buffer overflow */
+                (unlikely(op + (1 + LASTLITERALS) + (matchCode + 240) / 255 > olimit)))
+            {
+                if (outputDirective == fillOutput)
+                {
+                    /* Match description too long : reduce it */
+                    U32 newMatchCode = 15 /* in token */ - 1 /* to avoid needing a zero byte */ + ((U32)(olimit - op) - 1 - LASTLITERALS) * 255;
+                    ip -= matchCode - newMatchCode;
+                    assert(newMatchCode < matchCode);
+                    matchCode = newMatchCode;
+                    if (unlikely(ip <= filledIp))
+                    {
+                        /* We have already filled up to filledIp so if ip ends up less than filledIp
+                         * we have positions in the hash table beyond the current position. This is
+                         * a problem if we reuse the hash table. So we have to remove these positions
+                         * from the hash table.
+                         */
+                        const BYTE *ptr;
+                        DEBUGLOG(5, "Clearing %u positions", (U32)(filledIp - ip));
+                        for (ptr = ip; ptr <= filledIp; ++ptr)
+                        {
+                            U32 const h = LZ4_hashPosition(ptr, tableType);
+                            LZ4_clearHash(h, cctx->hashTable, tableType);
+                        }
+                    }
+                }
+                else
+                {
+                    assert(outputDirective == limitedOutput);
+                    return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */
+                }
+            }
+            if (matchCode >= ML_MASK)
+            {
+                *token += ML_MASK;
+                matchCode -= ML_MASK;
+                LZ4_write32(op, 0xFFFFFFFF);
+                while (matchCode >= 4 * 255)
+                {
+                    op += 4;
+                    LZ4_write32(op, 0xFFFFFFFF);
+                    matchCode -= 4 * 255;
+                }
+                op += matchCode / 255;
+                *op++ = (BYTE)(matchCode % 255);
+            }
+            else
+                *token += (BYTE)(matchCode);
+        }
+        /* Ensure we have enough space for the last literals. */
+        assert(!(outputDirective == fillOutput && op + 1 + LASTLITERALS > olimit));
+
+        anchor = ip;
+
+        /* Test end of chunk */
+        if (ip >= mflimitPlusOne)
+            break;
+
+        /* Fill table */
+        LZ4_putPosition(ip - 2, cctx->hashTable, tableType, base);
+
+        /* Test next position */
+        if (tableType == byPtr)
+        {
+
+            match = LZ4_getPosition(ip, cctx->hashTable, tableType, base);
+            LZ4_putPosition(ip, cctx->hashTable, tableType, base);
+            if ((match + LZ4_DISTANCE_MAX >= ip) && (LZ4_read32(match) == LZ4_read32(ip)))
+            {
+                token = op++;
+                *token = 0;
+                goto _next_match;
+            }
+        }
+        else
+        { /* byU32, byU16 */
+
+            U32 const h = LZ4_hashPosition(ip, tableType);
+            U32 const current = (U32)(ip - base);
+            U32 matchIndex = LZ4_getIndexOnHash(h, cctx->hashTable, tableType);
+            assert(matchIndex < current);
+            if (dictDirective == usingDictCtx)
+            {
+                if (matchIndex < startIndex)
+                {
+                    /* there was no match, try the dictionary */
+                    matchIndex = LZ4_getIndexOnHash(h, dictCtx->hashTable, byU32);
+                    match = dictBase + matchIndex;
+                    lowLimit = dictionary; /* required for match length counter */
+                    matchIndex += dictDelta;
+                }
+                else
+                {
+                    match = base + matchIndex;
+                    lowLimit = (const BYTE *)source; /* required for match length counter */
+                }
+            }
+            else if (dictDirective == usingExtDict)
+            {
+                if (matchIndex < startIndex)
+                {
+                    match = dictBase + matchIndex;
+                    lowLimit = dictionary; /* required for match length counter */
+                }
+                else
+                {
+                    match = base + matchIndex;
+                    lowLimit = (const BYTE *)source; /* required for match length counter */
+                }
+            }
+            else
+            { /* single memory segment */
+                match = base + matchIndex;
+            }
+            LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType);
+            assert(matchIndex < current);
+            if (((dictIssue == dictSmall) ? (matchIndex >= prefixIdxLimit) : 1) && (((tableType == byU16) && (LZ4_DISTANCE_MAX == LZ4_DISTANCE_ABSOLUTE_MAX)) ? 1 : (matchIndex + LZ4_DISTANCE_MAX >= current)) && (LZ4_read32(match) == LZ4_read32(ip)))
+            {
+                token = op++;
+                *token = 0;
+                if (maybe_extMem)
+                    offset = current - matchIndex;
+                DEBUGLOG(6, "seq.start:%i, literals=%u, match.start:%i",
+                         (int)(anchor - (const BYTE *)source), 0, (int)(ip - (const BYTE *)source));
+                goto _next_match;
+            }
+        }
+
+        /* Prepare next loop */
+        forwardH = LZ4_hashPosition(++ip, tableType);
+    }
+
+_last_literals:
+    /* Encode Last Literals */
+    {
+        size_t lastRun = (size_t)(iend - anchor);
+        if ((outputDirective) && /* Check output buffer overflow */
+            (op + lastRun + 1 + ((lastRun + 255 - RUN_MASK) / 255) > olimit))
+        {
+            if (outputDirective == fillOutput)
+            {
+                /* adapt lastRun to fill 'dst' */
+                assert(olimit >= op);
+                lastRun = (size_t)(olimit - op) - 1 /*token*/;
+                lastRun -= (lastRun + 256 - RUN_MASK) / 256; /*additional length tokens*/
+            }
+            else
+            {
+                assert(outputDirective == limitedOutput);
+                return 0; /* cannot compress within `dst` budget. Stored indexes in hash table are nonetheless fine */
+            }
+        }
+        DEBUGLOG(6, "Final literal run : %i literals", (int)lastRun);
+        if (lastRun >= RUN_MASK)
+        {
+            size_t accumulator = lastRun - RUN_MASK;
+            *op++ = RUN_MASK << ML_BITS;
+            for (; accumulator >= 255; accumulator -= 255)
+                *op++ = 255;
+            *op++ = (BYTE)accumulator;
+        }
+        else
+        {
+            *op++ = (BYTE)(lastRun << ML_BITS);
+        }
+        LZ4_memcpy(op, anchor, lastRun);
+        ip = anchor + lastRun;
+        op += lastRun;
+    }
+
+    if (outputDirective == fillOutput)
+    {
+        *inputConsumed = (int)(((const char *)ip) - source);
+    }
+    result = (int)(((char *)op) - dest);
+    assert(result > 0);
+    DEBUGLOG(5, "LZ4_compress_generic: compressed %i bytes into %i bytes", inputSize, result);
+    return result;
+}
+
+/** LZ4_compress_generic() :
+ *  inlined, to ensure branches are decided at compilation time;
+ *  takes care of src == (NULL, 0)
+ *  and forward the rest to LZ4_compress_generic_validated */
+LZ4_FORCE_INLINE int LZ4_compress_generic(
+    LZ4_stream_t_internal *const cctx,
+    const char *const src,
+    char *const dst,
+    const int srcSize,
+    int *inputConsumed, /* only written when outputDirective == fillOutput */
+    const int dstCapacity,
+    const limitedOutput_directive outputDirective,
+    const tableType_t tableType,
+    const dict_directive dictDirective,
+    const dictIssue_directive dictIssue,
+    const int acceleration)
+{
+    DEBUGLOG(5, "LZ4_compress_generic: srcSize=%i, dstCapacity=%i",
+             srcSize, dstCapacity);
+
+    if ((U32)srcSize > (U32)LZ4_MAX_INPUT_SIZE)
+    {
+        return 0;
+    } /* Unsupported srcSize, too large (or negative) */
+    if (srcSize == 0)
+    { /* src == NULL supported if srcSize == 0 */
+        if (outputDirective != notLimited && dstCapacity <= 0)
+            return 0; /* no output, can't write anything */
+        DEBUGLOG(5, "Generating an empty block");
+        assert(outputDirective == notLimited || dstCapacity >= 1);
+        assert(dst != NULL);
+        dst[0] = 0;
+        if (outputDirective == fillOutput)
+        {
+            assert(inputConsumed != NULL);
+            *inputConsumed = 0;
+        }
+        return 1;
+    }
+    assert(src != NULL);
+
+    return LZ4_compress_generic_validated(cctx, src, dst, srcSize,
+                                          inputConsumed, /* only written into if outputDirective == fillOutput */
+                                          dstCapacity, outputDirective,
+                                          tableType, dictDirective, dictIssue, acceleration);
+}
+
+int LZ4_compress_fast_extState(void *state, const char *source, char *dest, int inputSize, int maxOutputSize, int acceleration)
+{
+    LZ4_stream_t_internal *const ctx = &LZ4_initStream(state, sizeof(LZ4_stream_t))->internal_donotuse;
+    assert(ctx != NULL);
+    if (acceleration < 1)
+        acceleration = LZ4_ACCELERATION_DEFAULT;
+    if (acceleration > LZ4_ACCELERATION_MAX)
+        acceleration = LZ4_ACCELERATION_MAX;
+    if (maxOutputSize >= LZ4_compressBound(inputSize))
+    {
+        if (inputSize < LZ4_64Klimit)
+        {
+            return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, byU16, noDict, noDictIssue, acceleration);
+        }
+        else
+        {
+            const tableType_t tableType = ((sizeof(void *) == 4) && ((uptrval)source > LZ4_DISTANCE_MAX)) ? byPtr : byU32;
+            return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
+        }
+    }
+    else
+    {
+        if (inputSize < LZ4_64Klimit)
+        {
+            return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
+        }
+        else
+        {
+            const tableType_t tableType = ((sizeof(void *) == 4) && ((uptrval)source > LZ4_DISTANCE_MAX)) ? byPtr : byU32;
+            return LZ4_compress_generic(ctx, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, noDict, noDictIssue, acceleration);
+        }
+    }
+}
+
+/**
+ * LZ4_compress_fast_extState_fastReset() :
+ * A variant of LZ4_compress_fast_extState().
+ *
+ * Using this variant avoids an expensive initialization step. It is only safe
+ * to call if the state buffer is known to be correctly initialized already
+ * (see comment in lz4.h on LZ4_resetStream_fast() for a definition of
+ * "correctly initialized").
+ */
+int LZ4_compress_fast_extState_fastReset(void *state, const char *src, char *dst, int srcSize, int dstCapacity, int acceleration)
+{
+    LZ4_stream_t_internal *ctx = &((LZ4_stream_t *)state)->internal_donotuse;
+    if (acceleration < 1)
+        acceleration = LZ4_ACCELERATION_DEFAULT;
+    if (acceleration > LZ4_ACCELERATION_MAX)
+        acceleration = LZ4_ACCELERATION_MAX;
+
+    if (dstCapacity >= LZ4_compressBound(srcSize))
+    {
+        if (srcSize < LZ4_64Klimit)
+        {
+            const tableType_t tableType = byU16;
+            LZ4_prepareTable(ctx, srcSize, tableType);
+            if (ctx->currentOffset)
+            {
+                return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, dictSmall, acceleration);
+            }
+            else
+            {
+                return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
+            }
+        }
+        else
+        {
+            const tableType_t tableType = ((sizeof(void *) == 4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32;
+            LZ4_prepareTable(ctx, srcSize, tableType);
+            return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, 0, notLimited, tableType, noDict, noDictIssue, acceleration);
+        }
+    }
+    else
+    {
+        if (srcSize < LZ4_64Klimit)
+        {
+            const tableType_t tableType = byU16;
+            LZ4_prepareTable(ctx, srcSize, tableType);
+            if (ctx->currentOffset)
+            {
+                return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, dictSmall, acceleration);
+            }
+            else
+            {
+                return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration);
+            }
+        }
+        else
+        {
+            const tableType_t tableType = ((sizeof(void *) == 4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32;
+            LZ4_prepareTable(ctx, srcSize, tableType);
+            return LZ4_compress_generic(ctx, src, dst, srcSize, NULL, dstCapacity, limitedOutput, tableType, noDict, noDictIssue, acceleration);
+        }
+    }
+}
+
+int LZ4_compress_fast(const char *source, char *dest, int inputSize, int maxOutputSize, int acceleration)
+{
+    int result;
+#if (LZ4_HEAPMODE)
+    LZ4_stream_t *ctxPtr = ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
+    if (ctxPtr == NULL)
+        return 0;
+#else
+    LZ4_stream_t ctx;
+    LZ4_stream_t *const ctxPtr = &ctx;
+#endif
+    result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration);
+
+#if (LZ4_HEAPMODE)
+    FREEMEM(ctxPtr);
+#endif
+    return result;
+}
+
+int LZ4_compress_default(const char *src, char *dst, int srcSize, int maxOutputSize)
+{
+    return LZ4_compress_fast(src, dst, srcSize, maxOutputSize, 1);
+}
+
+/* Note!: This function leaves the stream in an unclean/broken state!
+ * It is not safe to subsequently use the same state with a _fastReset() or
+ * _continue() call without resetting it. */
+static int LZ4_compress_destSize_extState(LZ4_stream_t *state, const char *src, char *dst, int *srcSizePtr, int targetDstSize)
+{
+    void *const s = LZ4_initStream(state, sizeof(*state));
+    assert(s != NULL);
+    (void)s;
+
+    if (targetDstSize >= LZ4_compressBound(*srcSizePtr))
+    { /* compression success is guaranteed */
+        return LZ4_compress_fast_extState(state, src, dst, *srcSizePtr, targetDstSize, 1);
+    }
+    else
+    {
+        if (*srcSizePtr < LZ4_64Klimit)
+        {
+            return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, byU16, noDict, noDictIssue, 1);
+        }
+        else
+        {
+            tableType_t const addrMode = ((sizeof(void *) == 4) && ((uptrval)src > LZ4_DISTANCE_MAX)) ? byPtr : byU32;
+            return LZ4_compress_generic(&state->internal_donotuse, src, dst, *srcSizePtr, srcSizePtr, targetDstSize, fillOutput, addrMode, noDict, noDictIssue, 1);
+        }
+    }
+}
+
+int LZ4_compress_destSize(const char *src, char *dst, int *srcSizePtr, int targetDstSize)
+{
+#if (LZ4_HEAPMODE)
+    LZ4_stream_t *ctx = (LZ4_stream_t *)ALLOC(sizeof(LZ4_stream_t)); /* malloc-calloc always properly aligned */
+    if (ctx == NULL)
+        return 0;
+#else
+    LZ4_stream_t ctxBody;
+    LZ4_stream_t *ctx = &ctxBody;
+#endif
+
+    int result = LZ4_compress_destSize_extState(ctx, src, dst, srcSizePtr, targetDstSize);
+
+#if (LZ4_HEAPMODE)
+    FREEMEM(ctx);
+#endif
+    return result;
+}
+
+/*-******************************
+ *  Streaming functions
+ ********************************/
+
+LZ4_stream_t *LZ4_createStream(void)
+{
+    LZ4_stream_t *const lz4s = (LZ4_stream_t *)ALLOC(sizeof(LZ4_stream_t));
+    LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /* A compilation error here means LZ4_STREAMSIZE is not large enough */
+    DEBUGLOG(4, "LZ4_createStream %p", lz4s);
+    if (lz4s == NULL)
+        return NULL;
+    LZ4_initStream(lz4s, sizeof(*lz4s));
+    return lz4s;
+}
+
+static size_t LZ4_stream_t_alignment(void)
+{
+#if LZ4_ALIGN_TEST
+    typedef struct
+    {
+        char c;
+        LZ4_stream_t t;
+    } t_a;
+    return sizeof(t_a) - sizeof(LZ4_stream_t);
+#else
+    return 1; /* effectively disabled */
+#endif
+}
+
+LZ4_stream_t *LZ4_initStream(void *buffer, size_t size)
+{
+    DEBUGLOG(5, "LZ4_initStream");
+    if (buffer == NULL)
+    {
+        return NULL;
+    }
+    if (size < sizeof(LZ4_stream_t))
+    {
+        return NULL;
+    }
+    if (!LZ4_isAligned(buffer, LZ4_stream_t_alignment()))
+        return NULL;
+    MEM_INIT(buffer, 0, sizeof(LZ4_stream_t_internal));
+    return (LZ4_stream_t *)buffer;
+}
+
+/* resetStream is now deprecated,
+ * prefer initStream() which is more general */
+void LZ4_resetStream(LZ4_stream_t *LZ4_stream)
+{
+    DEBUGLOG(5, "LZ4_resetStream (ctx:%p)", LZ4_stream);
+    MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t_internal));
+}
+
+void LZ4_resetStream_fast(LZ4_stream_t *ctx)
+{
+    LZ4_prepareTable(&(ctx->internal_donotuse), 0, byU32);
+}
+
+int LZ4_freeStream(LZ4_stream_t *LZ4_stream)
+{
+    if (!LZ4_stream)
+        return 0; /* support free on NULL */
+    DEBUGLOG(5, "LZ4_freeStream %p", LZ4_stream);
+    FREEMEM(LZ4_stream);
+    return (0);
+}
+
+#define HASH_UNIT sizeof(reg_t)
+int LZ4_loadDict(LZ4_stream_t *LZ4_dict, const char *dictionary, int dictSize)
+{
+    LZ4_stream_t_internal *dict = &LZ4_dict->internal_donotuse;
+    const tableType_t tableType = byU32;
+    const BYTE *p = (const BYTE *)dictionary;
+    const BYTE *const dictEnd = p + dictSize;
+    const BYTE *base;
+
+    DEBUGLOG(4, "LZ4_loadDict (%i bytes from %p into %p)", dictSize, dictionary, LZ4_dict);
+
+    /* It's necessary to reset the context,
+     * and not just continue it with prepareTable()
+     * to avoid any risk of generating overflowing matchIndex
+     * when compressing using this dictionary */
+    LZ4_resetStream(LZ4_dict);
+
+    /* We always increment the offset by 64 KB, since, if the dict is longer,
+     * we truncate it to the last 64k, and if it's shorter, we still want to
+     * advance by a whole window length so we can provide the guarantee that
+     * there are only valid offsets in the window, which allows an optimization
+     * in LZ4_compress_fast_continue() where it uses noDictIssue even when the
+     * dictionary isn't a full 64k. */
+    dict->currentOffset += 64 KB;
+
+    if (dictSize < (int)HASH_UNIT)
+    {
+        return 0;
+    }
+
+    if ((dictEnd - p) > 64 KB)
+        p = dictEnd - 64 KB;
+    base = dictEnd - dict->currentOffset;
+    dict->dictionary = p;
+    dict->dictSize = (U32)(dictEnd - p);
+    dict->tableType = (U32)tableType;
+
+    while (p <= dictEnd - HASH_UNIT)
+    {
+        LZ4_putPosition(p, dict->hashTable, tableType, base);
+        p += 3;
+    }
+
+    return (int)dict->dictSize;
+}
+
+void LZ4_attach_dictionary(LZ4_stream_t *workingStream, const LZ4_stream_t *dictionaryStream)
+{
+    const LZ4_stream_t_internal *dictCtx = dictionaryStream == NULL ? NULL : &(dictionaryStream->internal_donotuse);
+
+    DEBUGLOG(4, "LZ4_attach_dictionary (%p, %p, size %u)",
+             workingStream, dictionaryStream,
+             dictCtx != NULL ? dictCtx->dictSize : 0);
+
+    if (dictCtx != NULL)
+    {
+        /* If the current offset is zero, we will never look in the
+         * external dictionary context, since there is no value a table
+         * entry can take that indicate a miss. In that case, we need
+         * to bump the offset to something non-zero.
+         */
+        if (workingStream->internal_donotuse.currentOffset == 0)
+        {
+            workingStream->internal_donotuse.currentOffset = 64 KB;
+        }
+
+        /* Don't actually attach an empty dictionary.
+         */
+        if (dictCtx->dictSize == 0)
+        {
+            dictCtx = NULL;
+        }
+    }
+    workingStream->internal_donotuse.dictCtx = dictCtx;
+}
+
+static void LZ4_renormDictT(LZ4_stream_t_internal *LZ4_dict, int nextSize)
+{
+    assert(nextSize >= 0);
+    if (LZ4_dict->currentOffset + (unsigned)nextSize > 0x80000000)
+    { /* potential ptrdiff_t overflow (32-bits mode) */
+        /* rescale hash table */
+        U32 const delta = LZ4_dict->currentOffset - 64 KB;
+        const BYTE *dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize;
+        int i;
+        DEBUGLOG(4, "LZ4_renormDictT");
+        for (i = 0; i < LZ4_HASH_SIZE_U32; i++)
+        {
+            if (LZ4_dict->hashTable[i] < delta)
+                LZ4_dict->hashTable[i] = 0;
+            else
+                LZ4_dict->hashTable[i] -= delta;
+        }
+        LZ4_dict->currentOffset = 64 KB;
+        if (LZ4_dict->dictSize > 64 KB)
+            LZ4_dict->dictSize = 64 KB;
+        LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize;
+    }
+}
+
+int LZ4_compress_fast_continue(LZ4_stream_t *LZ4_stream,
+                               const char *source, char *dest,
+                               int inputSize, int maxOutputSize,
+                               int acceleration)
+{
+    const tableType_t tableType = byU32;
+    LZ4_stream_t_internal *streamPtr = &LZ4_stream->internal_donotuse;
+    const BYTE *dictEnd = streamPtr->dictionary + streamPtr->dictSize;
+
+    DEBUGLOG(5, "LZ4_compress_fast_continue (inputSize=%i)", inputSize);
+
+    LZ4_renormDictT(streamPtr, inputSize); /* avoid index overflow */
+    if (acceleration < 1)
+        acceleration = LZ4_ACCELERATION_DEFAULT;
+    if (acceleration > LZ4_ACCELERATION_MAX)
+        acceleration = LZ4_ACCELERATION_MAX;
+
+    /* invalidate tiny dictionaries */
+    if ((streamPtr->dictSize - 1 < 4 - 1) /* intentional underflow */
+        && (dictEnd != (const BYTE *)source))
+    {
+        DEBUGLOG(5, "LZ4_compress_fast_continue: dictSize(%u) at addr:%p is too small", streamPtr->dictSize, streamPtr->dictionary);
+        streamPtr->dictSize = 0;
+        streamPtr->dictionary = (const BYTE *)source;
+        dictEnd = (const BYTE *)source;
+    }
+
+    /* Check overlapping input/dictionary space */
+    {
+        const BYTE *sourceEnd = (const BYTE *)source + inputSize;
+        if ((sourceEnd > streamPtr->dictionary) && (sourceEnd < dictEnd))
+        {
+            streamPtr->dictSize = (U32)(dictEnd - sourceEnd);
+            if (streamPtr->dictSize > 64 KB)
+                streamPtr->dictSize = 64 KB;
+            if (streamPtr->dictSize < 4)
+                streamPtr->dictSize = 0;
+            streamPtr->dictionary = dictEnd - streamPtr->dictSize;
+        }
+    }
+
+    /* prefix mode : source data follows dictionary */
+    if (dictEnd == (const BYTE *)source)
+    {
+        if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
+            return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, dictSmall, acceleration);
+        else
+            return LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, withPrefix64k, noDictIssue, acceleration);
+    }
+
+    /* external dictionary mode */
+    {
+        int result;
+        if (streamPtr->dictCtx)
+        {
+            /* We depend here on the fact that dictCtx'es (produced by
+             * LZ4_loadDict) guarantee that their tables contain no references
+             * to offsets between dictCtx->currentOffset - 64 KB and
+             * dictCtx->currentOffset - dictCtx->dictSize. This makes it safe
+             * to use noDictIssue even when the dict isn't a full 64 KB.
+             */
+            if (inputSize > 4 KB)
+            {
+                /* For compressing large blobs, it is faster to pay the setup
+                 * cost to copy the dictionary's tables into the active context,
+                 * so that the compression loop is only looking into one table.
+                 */
+                LZ4_memcpy(streamPtr, streamPtr->dictCtx, sizeof(*streamPtr));
+                result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration);
+            }
+            else
+            {
+                result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingDictCtx, noDictIssue, acceleration);
+            }
+        }
+        else
+        {
+            if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
+            {
+                result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, dictSmall, acceleration);
+            }
+            else
+            {
+                result = LZ4_compress_generic(streamPtr, source, dest, inputSize, NULL, maxOutputSize, limitedOutput, tableType, usingExtDict, noDictIssue, acceleration);
+            }
+        }
+        streamPtr->dictionary = (const BYTE *)source;
+        streamPtr->dictSize = (U32)inputSize;
+        return result;
+    }
+}
+
+/* Hidden debug function, to force-test external dictionary mode */
+int LZ4_compress_forceExtDict(LZ4_stream_t *LZ4_dict, const char *source, char *dest, int srcSize)
+{
+    LZ4_stream_t_internal *streamPtr = &LZ4_dict->internal_donotuse;
+    int result;
+
+    LZ4_renormDictT(streamPtr, srcSize);
+
+    if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset))
+    {
+        result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, dictSmall, 1);
+    }
+    else
+    {
+        result = LZ4_compress_generic(streamPtr, source, dest, srcSize, NULL, 0, notLimited, byU32, usingExtDict, noDictIssue, 1);
+    }
+
+    streamPtr->dictionary = (const BYTE *)source;
+    streamPtr->dictSize = (U32)srcSize;
+
+    return result;
+}
+
+/*! LZ4_saveDict() :
+ *  If previously compressed data block is not guaranteed to remain available at its memory location,
+ *  save it into a safer place (char* safeBuffer).
+ *  Note : you don't need to call LZ4_loadDict() afterwards,
+ *         dictionary is immediately usable, you can therefore call LZ4_compress_fast_continue().
+ *  Return : saved dictionary size in bytes (necessarily <= dictSize), or 0 if error.
+ */
+int LZ4_saveDict(LZ4_stream_t *LZ4_dict, char *safeBuffer, int dictSize)
+{
+    LZ4_stream_t_internal *const dict = &LZ4_dict->internal_donotuse;
+    const BYTE *const previousDictEnd = dict->dictionary + dict->dictSize;
+
+    if ((U32)dictSize > 64 KB)
+    {
+        dictSize = 64 KB;
+    } /* useless to define a dictionary > 64 KB */
+    if ((U32)dictSize > dict->dictSize)
+    {
+        dictSize = (int)dict->dictSize;
+    }
+
+    if (safeBuffer == NULL)
+        assert(dictSize == 0);
+    if (dictSize > 0)
+        memmove(safeBuffer, previousDictEnd - dictSize, dictSize);
+
+    dict->dictionary = (const BYTE *)safeBuffer;
+    dict->dictSize = (U32)dictSize;
+
+    return dictSize;
+}
+
+/*-*******************************
+ *  Decompression functions
+ ********************************/
+
+typedef enum
+{
+    endOnOutputSize = 0,
+    endOnInputSize = 1
+} endCondition_directive;
+typedef enum
+{
+    decode_full_block = 0,
+    partial_decode = 1
+} earlyEnd_directive;
+
+#undef MIN
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+
+/* Read the variable-length literal or match length.
+ *
+ * ip - pointer to use as input.
+ * lencheck - end ip.  Return an error if ip advances >= lencheck.
+ * loop_check - check ip >= lencheck in body of loop.  Returns loop_error if so.
+ * initial_check - check ip >= lencheck before start of loop.  Returns initial_error if so.
+ * error (output) - error code.  Should be set to 0 before call.
+ */
+typedef enum
+{
+    loop_error = -2,
+    initial_error = -1,
+    ok = 0
+} variable_length_error;
+LZ4_FORCE_INLINE unsigned
+read_variable_length(const BYTE **ip, const BYTE *lencheck,
+                     int loop_check, int initial_check,
+                     variable_length_error *error)
+{
+    U32 length = 0;
+    U32 s;
+    if (initial_check && unlikely((*ip) >= lencheck))
+    { /* overflow detection */
+        *error = initial_error;
+        return length;
+    }
+    do
+    {
+        s = **ip;
+        (*ip)++;
+        length += s;
+        if (loop_check && unlikely((*ip) >= lencheck))
+        { /* overflow detection */
+            *error = loop_error;
+            return length;
+        }
+    } while (s == 255);
+
+    return length;
+}
+
+/*! LZ4_decompress_generic() :
+ *  This generic decompression function covers all use cases.
+ *  It shall be instantiated several times, using different sets of directives.
+ *  Note that it is important for performance that this function really get inlined,
+ *  in order to remove useless branches during compilation optimization.
+ */
+LZ4_FORCE_INLINE int
+LZ4_decompress_generic(
+    const char *const src,
+    char *const dst,
+    int srcSize,
+    int outputSize, /* If endOnInput==endOnInputSize, this value is `dstCapacity` */
+
+    endCondition_directive endOnInput,  /* endOnOutputSize, endOnInputSize */
+    earlyEnd_directive partialDecoding, /* full, partial */
+    dict_directive dict,                /* noDict, withPrefix64k, usingExtDict */
+    const BYTE *const lowPrefix,        /* always <= dst, == dst when no prefix */
+    const BYTE *const dictStart,        /* only if dict==usingExtDict */
+    const size_t dictSize               /* note : = 0 if noDict */
+)
+{
+    if (src == NULL)
+    {
+        return -1;
+    }
+
+    {
+        const BYTE *ip = (const BYTE *)src;
+        const BYTE *const iend = ip + srcSize;
+
+        BYTE *op = (BYTE *)dst;
+        BYTE *const oend = op + outputSize;
+        BYTE *cpy;
+
+        const BYTE *const dictEnd = (dictStart == NULL) ? NULL : dictStart + dictSize;
+
+        const int safeDecode = (endOnInput == endOnInputSize);
+        const int checkOffset = ((safeDecode) && (dictSize < (int)(64 KB)));
+
+        /* Set up the "end" pointers for the shortcut. */
+        const BYTE *const shortiend = iend - (endOnInput ? 14 : 8) /*maxLL*/ - 2 /*offset*/;
+        const BYTE *const shortoend = oend - (endOnInput ? 14 : 8) /*maxLL*/ - 18 /*maxML*/;
+
+        const BYTE *match;
+        size_t offset;
+        unsigned token;
+        size_t length;
+
+        DEBUGLOG(5, "LZ4_decompress_generic (srcSize:%i, dstSize:%i)", srcSize, outputSize);
+
+        /* Special cases */
+        assert(lowPrefix <= op);
+        if ((endOnInput) && (unlikely(outputSize == 0)))
+        {
+            /* Empty output buffer */
+            if (partialDecoding)
+                return 0;
+            return ((srcSize == 1) && (*ip == 0)) ? 0 : -1;
+        }
+        if ((!endOnInput) && (unlikely(outputSize == 0)))
+        {
+            return (*ip == 0 ? 1 : -1);
+        }
+        if ((endOnInput) && unlikely(srcSize == 0))
+        {
+            return -1;
+        }
+
+        /* Currently the fast loop shows a regression on qualcomm arm chips. */
+#if LZ4_FAST_DEC_LOOP
+        if ((oend - op) < FASTLOOP_SAFE_DISTANCE)
+        {
+            DEBUGLOG(6, "skip fast decode loop");
+            goto safe_decode;
+        }
+
+        /* Fast loop : decode sequences as long as output < iend-FASTLOOP_SAFE_DISTANCE */
+        while (1)
+        {
+            /* Main fastloop assertion: We can always wildcopy FASTLOOP_SAFE_DISTANCE */
+            assert(oend - op >= FASTLOOP_SAFE_DISTANCE);
+            if (endOnInput)
+            {
+                assert(ip < iend);
+            }
+            token = *ip++;
+            length = token >> ML_BITS; /* literal length */
+
+            assert(!endOnInput || ip <= iend); /* ip < iend before the increment */
+
+            /* decode literal length */
+            if (length == RUN_MASK)
+            {
+                variable_length_error error = ok;
+                length += read_variable_length(&ip, iend - RUN_MASK, (int)endOnInput, (int)endOnInput, &error);
+                if (error == initial_error)
+                {
+                    goto _output_error;
+                }
+                if ((safeDecode) && unlikely((uptrval)(op) + length < (uptrval)(op)))
+                {
+                    goto _output_error;
+                } /* overflow detection */
+                if ((safeDecode) && unlikely((uptrval)(ip) + length < (uptrval)(ip)))
+                {
+                    goto _output_error;
+                } /* overflow detection */
+
+                /* copy literals */
+                cpy = op + length;
+                LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH);
+                if (endOnInput)
+                { /* LZ4_decompress_safe() */
+                    if ((cpy > oend - 32) || (ip + length > iend - 32))
+                    {
+                        goto safe_literal_copy;
+                    }
+                    LZ4_wildCopy32(op, ip, cpy);
+                }
+                else
+                { /* LZ4_decompress_fast() */
+                    if (cpy > oend - 8)
+                    {
+                        goto safe_literal_copy;
+                    }
+                    LZ4_wildCopy8(op, ip, cpy); /* LZ4_decompress_fast() cannot copy more than 8 bytes at a time :
+                                                 * it doesn't know input length, and only relies on end-of-block properties */
+                }
+                ip += length;
+                op = cpy;
+            }
+            else
+            {
+                cpy = op + length;
+                if (endOnInput)
+                { /* LZ4_decompress_safe() */
+                    DEBUGLOG(7, "copy %u bytes in a 16-bytes stripe", (unsigned)length);
+                    /* We don't need to check oend, since we check it once for each loop below */
+                    if (ip > iend - (16 + 1 /*max lit + offset + nextToken*/))
+                    {
+                        goto safe_literal_copy;
+                    }
+                    /* Literals can only be 14, but hope compilers optimize if we copy by a register size */
+                    LZ4_memcpy(op, ip, 16);
+                }
+                else
+                { /* LZ4_decompress_fast() */
+                    /* LZ4_decompress_fast() cannot copy more than 8 bytes at a time :
+                     * it doesn't know input length, and relies on end-of-block properties */
+                    LZ4_memcpy(op, ip, 8);
+                    if (length > 8)
+                    {
+                        LZ4_memcpy(op + 8, ip + 8, 8);
+                    }
+                }
+                ip += length;
+                op = cpy;
+            }
+
+            /* get offset */
+            offset = LZ4_readLE16(ip);
+            ip += 2;
+            match = op - offset;
+            assert(match <= op);
+
+            /* get matchlength */
+            length = token & ML_MASK;
+
+            if (length == ML_MASK)
+            {
+                variable_length_error error = ok;
+                if ((checkOffset) && (unlikely(match + dictSize < lowPrefix)))
+                {
+                    goto _output_error;
+                } /* Error : offset outside buffers */
+                length += read_variable_length(&ip, iend - LASTLITERALS + 1, (int)endOnInput, 0, &error);
+                if (error != ok)
+                {
+                    goto _output_error;
+                }
+                if ((safeDecode) && unlikely((uptrval)(op) + length < (uptrval)op))
+                {
+                    goto _output_error;
+                } /* overflow detection */
+                length += MINMATCH;
+                if (op + length >= oend - FASTLOOP_SAFE_DISTANCE)
+                {
+                    goto safe_match_copy;
+                }
+            }
+            else
+            {
+                length += MINMATCH;
+                if (op + length >= oend - FASTLOOP_SAFE_DISTANCE)
+                {
+                    goto safe_match_copy;
+                }
+
+                /* Fastpath check: Avoids a branch in LZ4_wildCopy32 if true */
+                if ((dict == withPrefix64k) || (match >= lowPrefix))
+                {
+                    if (offset >= 8)
+                    {
+                        assert(match >= lowPrefix);
+                        assert(match <= op);
+                        assert(op + 18 <= oend);
+
+                        LZ4_memcpy(op, match, 8);
+                        LZ4_memcpy(op + 8, match + 8, 8);
+                        LZ4_memcpy(op + 16, match + 16, 2);
+                        op += length;
+                        continue;
+                    }
+                }
+            }
+
+            if (checkOffset && (unlikely(match + dictSize < lowPrefix)))
+            {
+                goto _output_error;
+            } /* Error : offset outside buffers */
+            /* match starting within external dictionary */
+            if ((dict == usingExtDict) && (match < lowPrefix))
+            {
+                if (unlikely(op + length > oend - LASTLITERALS))
+                {
+                    if (partialDecoding)
+                    {
+                        DEBUGLOG(7, "partialDecoding: dictionary match, close to dstEnd");
+                        length = MIN(length, (size_t)(oend - op));
+                    }
+                    else
+                    {
+                        goto _output_error; /* end-of-block condition violated */
+                    }
+                }
+
+                if (length <= (size_t)(lowPrefix - match))
+                {
+                    /* match fits entirely within external dictionary : just copy */
+                    memmove(op, dictEnd - (lowPrefix - match), length);
+                    op += length;
+                }
+                else
+                {
+                    /* match stretches into both external dictionary and current block */
+                    size_t const copySize = (size_t)(lowPrefix - match);
+                    size_t const restSize = length - copySize;
+                    LZ4_memcpy(op, dictEnd - copySize, copySize);
+                    op += copySize;
+                    if (restSize > (size_t)(op - lowPrefix))
+                    { /* overlap copy */
+                        BYTE *const endOfMatch = op + restSize;
+                        const BYTE *copyFrom = lowPrefix;
+                        while (op < endOfMatch)
+                        {
+                            *op++ = *copyFrom++;
+                        }
+                    }
+                    else
+                    {
+                        LZ4_memcpy(op, lowPrefix, restSize);
+                        op += restSize;
+                    }
+                }
+                continue;
+            }
+
+            /* copy match within block */
+            cpy = op + length;
+
+            assert((op <= oend) && (oend - op >= 32));
+            if (unlikely(offset < 16))
+            {
+                LZ4_memcpy_using_offset(op, match, cpy, offset);
+            }
+            else
+            {
+                LZ4_wildCopy32(op, match, cpy);
+            }
+
+            op = cpy; /* wildcopy correction */
+        }
+    safe_decode:
+#endif
+
+        /* Main Loop : decode remaining sequences where output < FASTLOOP_SAFE_DISTANCE */
+        while (1)
+        {
+            token = *ip++;
+            length = token >> ML_BITS; /* literal length */
+
+            assert(!endOnInput || ip <= iend); /* ip < iend before the increment */
+
+            /* A two-stage shortcut for the most common case:
+             * 1) If the literal length is 0..14, and there is enough space,
+             * enter the shortcut and copy 16 bytes on behalf of the literals
+             * (in the fast mode, only 8 bytes can be safely copied this way).
+             * 2) Further if the match length is 4..18, copy 18 bytes in a similar
+             * manner; but we ensure that there's enough space in the output for
+             * those 18 bytes earlier, upon entering the shortcut (in other words,
+             * there is a combined check for both stages).
+             */
+            if ((endOnInput ? length != RUN_MASK : length <= 8)
+                /* strictly "less than" on input, to re-enter the loop with at least one byte */
+                && likely((endOnInput ? ip < shortiend : 1) & (op <= shortoend)))
+            {
+                /* Copy the literals */
+                LZ4_memcpy(op, ip, endOnInput ? 16 : 8);
+                op += length;
+                ip += length;
+
+                /* The second stage: prepare for match copying, decode full info.
+                 * If it doesn't work out, the info won't be wasted. */
+                length = token & ML_MASK; /* match length */
+                offset = LZ4_readLE16(ip);
+                ip += 2;
+                match = op - offset;
+                assert(match <= op); /* check overflow */
+
+                /* Do not deal with overlapping matches. */
+                if ((length != ML_MASK) && (offset >= 8) && (dict == withPrefix64k || match >= lowPrefix))
+                {
+                    /* Copy the match. */
+                    LZ4_memcpy(op + 0, match + 0, 8);
+                    LZ4_memcpy(op + 8, match + 8, 8);
+                    LZ4_memcpy(op + 16, match + 16, 2);
+                    op += length + MINMATCH;
+                    /* Both stages worked, load the next token. */
+                    continue;
+                }
+
+                /* The second stage didn't work out, but the info is ready.
+                 * Propel it right to the point of match copying. */
+                goto _copy_match;
+            }
+
+            /* decode literal length */
+            if (length == RUN_MASK)
+            {
+                variable_length_error error = ok;
+                length += read_variable_length(&ip, iend - RUN_MASK, (int)endOnInput, (int)endOnInput, &error);
+                if (error == initial_error)
+                {
+                    goto _output_error;
+                }
+                if ((safeDecode) && unlikely((uptrval)(op) + length < (uptrval)(op)))
+                {
+                    goto _output_error;
+                } /* overflow detection */
+                if ((safeDecode) && unlikely((uptrval)(ip) + length < (uptrval)(ip)))
+                {
+                    goto _output_error;
+                } /* overflow detection */
+            }
+
+            /* copy literals */
+            cpy = op + length;
+#if LZ4_FAST_DEC_LOOP
+        safe_literal_copy:
+#endif
+            LZ4_STATIC_ASSERT(MFLIMIT >= WILDCOPYLENGTH);
+            if (((endOnInput) && ((cpy > oend - MFLIMIT) || (ip + length > iend - (2 + 1 + LASTLITERALS)))) || ((!endOnInput) && (cpy > oend - WILDCOPYLENGTH)))
+            {
+                /* We've either hit the input parsing restriction or the output parsing restriction.
+                 * In the normal scenario, decoding a full block, it must be the last sequence,
+                 * otherwise it's an error (invalid input or dimensions).
+                 * In partialDecoding scenario, it's necessary to ensure there is no buffer overflow.
+                 */
+                if (partialDecoding)
+                {
+                    /* Since we are partial decoding we may be in this block because of the output parsing
+                     * restriction, which is not valid since the output buffer is allowed to be undersized.
+                     */
+                    assert(endOnInput);
+                    DEBUGLOG(7, "partialDecoding: copying literals, close to input or output end")
+                    DEBUGLOG(7, "partialDecoding: literal length = %u", (unsigned)length);
+                    DEBUGLOG(7, "partialDecoding: remaining space in dstBuffer : %i", (int)(oend - op));
+                    DEBUGLOG(7, "partialDecoding: remaining space in srcBuffer : %i", (int)(iend - ip));
+                    /* Finishing in the middle of a literals segment,
+                     * due to lack of input.
+                     */
+                    if (ip + length > iend)
+                    {
+                        length = (size_t)(iend - ip);
+                        cpy = op + length;
+                    }
+                    /* Finishing in the middle of a literals segment,
+                     * due to lack of output space.
+                     */
+                    if (cpy > oend)
+                    {
+                        cpy = oend;
+                        assert(op <= oend);
+                        length = (size_t)(oend - op);
+                    }
+                }
+                else
+                {
+                    /* We must be on the last sequence because of the parsing limitations so check
+                     * that we exactly regenerate the original size (must be exact when !endOnInput).
+                     */
+                    if ((!endOnInput) && (cpy != oend))
+                    {
+                        goto _output_error;
+                    }
+                    /* We must be on the last sequence (or invalid) because of the parsing limitations
+                     * so check that we exactly consume the input and don't overrun the output buffer.
+                     */
+                    if ((endOnInput) && ((ip + length != iend) || (cpy > oend)))
+                    {
+                        DEBUGLOG(6, "should have been last run of literals")
+                        DEBUGLOG(6, "ip(%p) + length(%i) = %p != iend (%p)", ip, (int)length, ip + length, iend);
+                        DEBUGLOG(6, "or cpy(%p) > oend(%p)", cpy, oend);
+                        goto _output_error;
+                    }
+                }
+                memmove(op, ip, length); /* supports overlapping memory regions; only matters for in-place decompression scenarios */
+                ip += length;
+                op += length;
+                /* Necessarily EOF when !partialDecoding.
+                 * When partialDecoding, it is EOF if we've either
+                 * filled the output buffer or
+                 * can't proceed with reading an offset for following match.
+                 */
+                if (!partialDecoding || (cpy == oend) || (ip >= (iend - 2)))
+                {
+                    break;
+                }
+            }
+            else
+            {
+                LZ4_wildCopy8(op, ip, cpy); /* may overwrite up to WILDCOPYLENGTH beyond cpy */
+                ip += length;
+                op = cpy;
+            }
+
+            /* get offset */
+            offset = LZ4_readLE16(ip);
+            ip += 2;
+            match = op - offset;
+
+            /* get matchlength */
+            length = token & ML_MASK;
+
+        _copy_match:
+            if (length == ML_MASK)
+            {
+                variable_length_error error = ok;
+                length += read_variable_length(&ip, iend - LASTLITERALS + 1, (int)endOnInput, 0, &error);
+                if (error != ok)
+                    goto _output_error;
+                if ((safeDecode) && unlikely((uptrval)(op) + length < (uptrval)op))
+                    goto _output_error; /* overflow detection */
+            }
+            length += MINMATCH;
+
+#if LZ4_FAST_DEC_LOOP
+        safe_match_copy:
+#endif
+            if ((checkOffset) && (unlikely(match + dictSize < lowPrefix)))
+                goto _output_error; /* Error : offset outside buffers */
+            /* match starting within external dictionary */
+            if ((dict == usingExtDict) && (match < lowPrefix))
+            {
+                if (unlikely(op + length > oend - LASTLITERALS))
+                {
+                    if (partialDecoding)
+                        length = MIN(length, (size_t)(oend - op));
+                    else
+                        goto _output_error; /* doesn't respect parsing restriction */
+                }
+
+                if (length <= (size_t)(lowPrefix - match))
+                {
+                    /* match fits entirely within external dictionary : just copy */
+                    memmove(op, dictEnd - (lowPrefix - match), length);
+                    op += length;
+                }
+                else
+                {
+                    /* match stretches into both external dictionary and current block */
+                    size_t const copySize = (size_t)(lowPrefix - match);
+                    size_t const restSize = length - copySize;
+                    LZ4_memcpy(op, dictEnd - copySize, copySize);
+                    op += copySize;
+                    if (restSize > (size_t)(op - lowPrefix))
+                    { /* overlap copy */
+                        BYTE *const endOfMatch = op + restSize;
+                        const BYTE *copyFrom = lowPrefix;
+                        while (op < endOfMatch)
+                            *op++ = *copyFrom++;
+                    }
+                    else
+                    {
+                        LZ4_memcpy(op, lowPrefix, restSize);
+                        op += restSize;
+                    }
+                }
+                continue;
+            }
+            assert(match >= lowPrefix);
+
+            /* copy match within block */
+            cpy = op + length;
+
+            /* partialDecoding : may end anywhere within the block */
+            assert(op <= oend);
+            if (partialDecoding && (cpy > oend - MATCH_SAFEGUARD_DISTANCE))
+            {
+                size_t const mlen = MIN(length, (size_t)(oend - op));
+                const BYTE *const matchEnd = match + mlen;
+                BYTE *const copyEnd = op + mlen;
+                if (matchEnd > op)
+                { /* overlap copy */
+                    while (op < copyEnd)
+                    {
+                        *op++ = *match++;
+                    }
+                }
+                else
+                {
+                    LZ4_memcpy(op, match, mlen);
+                }
+                op = copyEnd;
+                if (op == oend)
+                {
+                    break;
+                }
+                continue;
+            }
+
+            if (unlikely(offset < 8))
+            {
+                LZ4_write32(op, 0); /* silence msan warning when offset==0 */
+                op[0] = match[0];
+                op[1] = match[1];
+                op[2] = match[2];
+                op[3] = match[3];
+                match += inc32table[offset];
+                LZ4_memcpy(op + 4, match, 4);
+                match -= dec64table[offset];
+            }
+            else
+            {
+                LZ4_memcpy(op, match, 8);
+                match += 8;
+            }
+            op += 8;
+
+            if (unlikely(cpy > oend - MATCH_SAFEGUARD_DISTANCE))
+            {
+                BYTE *const oCopyLimit = oend - (WILDCOPYLENGTH - 1);
+                if (cpy > oend - LASTLITERALS)
+                {
+                    goto _output_error;
+                } /* Error : last LASTLITERALS bytes must be literals (uncompressed) */
+                if (op < oCopyLimit)
+                {
+                    LZ4_wildCopy8(op, match, oCopyLimit);
+                    match += oCopyLimit - op;
+                    op = oCopyLimit;
+                }
+                while (op < cpy)
+                {
+                    *op++ = *match++;
+                }
+            }
+            else
+            {
+                LZ4_memcpy(op, match, 8);
+                if (length > 16)
+                {
+                    LZ4_wildCopy8(op + 8, match + 8, cpy);
+                }
+            }
+            op = cpy; /* wildcopy correction */
+        }
+
+        /* end of decoding */
+        if (endOnInput)
+        {
+            DEBUGLOG(5, "decoded %i bytes", (int)(((char *)op) - dst));
+            return (int)(((char *)op) - dst); /* Nb of output bytes decoded */
+        }
+        else
+        {
+            return (int)(((const char *)ip) - src); /* Nb of input bytes read */
+        }
+
+        /* Overflow error detected */
+    _output_error:
+        return (int)(-(((const char *)ip) - src)) - 1;
+    }
+}
+
+/*===== Instantiate the API decoding functions. =====*/
+
+LZ4_FORCE_O2
+int LZ4_decompress_safe(const char *source, char *dest, int compressedSize, int maxDecompressedSize)
+{
+    return LZ4_decompress_generic(source, dest, compressedSize, maxDecompressedSize,
+                                  endOnInputSize, decode_full_block, noDict,
+                                  (BYTE *)dest, NULL, 0);
+}
+
+LZ4_FORCE_O2
+int LZ4_decompress_safe_partial(const char *src, char *dst, int compressedSize, int targetOutputSize, int dstCapacity)
+{
+    dstCapacity = MIN(targetOutputSize, dstCapacity);
+    return LZ4_decompress_generic(src, dst, compressedSize, dstCapacity,
+                                  endOnInputSize, partial_decode,
+                                  noDict, (BYTE *)dst, NULL, 0);
+}
+
+LZ4_FORCE_O2
+int LZ4_decompress_fast(const char *source, char *dest, int originalSize)
+{
+    return LZ4_decompress_generic(source, dest, 0, originalSize,
+                                  endOnOutputSize, decode_full_block, withPrefix64k,
+                                  (BYTE *)dest - 64 KB, NULL, 0);
+}
+
+/*===== Instantiate a few more decoding cases, used more than once. =====*/
+
+LZ4_FORCE_O2 /* Exported, an obsolete API function. */
+    int
+    LZ4_decompress_safe_withPrefix64k(const char *source, char *dest, int compressedSize, int maxOutputSize)
+{
+    return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
+                                  endOnInputSize, decode_full_block, withPrefix64k,
+                                  (BYTE *)dest - 64 KB, NULL, 0);
+}
+
+/* Another obsolete API function, paired with the previous one. */
+int LZ4_decompress_fast_withPrefix64k(const char *source, char *dest, int originalSize)
+{
+    /* LZ4_decompress_fast doesn't validate match offsets,
+     * and thus serves well with any prefixed dictionary. */
+    return LZ4_decompress_fast(source, dest, originalSize);
+}
+
+LZ4_FORCE_O2
+static int LZ4_decompress_safe_withSmallPrefix(const char *source, char *dest, int compressedSize, int maxOutputSize,
+                                               size_t prefixSize)
+{
+    return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
+                                  endOnInputSize, decode_full_block, noDict,
+                                  (BYTE *)dest - prefixSize, NULL, 0);
+}
+
+LZ4_FORCE_O2
+int LZ4_decompress_safe_forceExtDict(const char *source, char *dest,
+                                     int compressedSize, int maxOutputSize,
+                                     const void *dictStart, size_t dictSize)
+{
+    return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
+                                  endOnInputSize, decode_full_block, usingExtDict,
+                                  (BYTE *)dest, (const BYTE *)dictStart, dictSize);
+}
+
+LZ4_FORCE_O2
+static int LZ4_decompress_fast_extDict(const char *source, char *dest, int originalSize,
+                                       const void *dictStart, size_t dictSize)
+{
+    return LZ4_decompress_generic(source, dest, 0, originalSize,
+                                  endOnOutputSize, decode_full_block, usingExtDict,
+                                  (BYTE *)dest, (const BYTE *)dictStart, dictSize);
+}
+
+/* The "double dictionary" mode, for use with e.g. ring buffers: the first part
+ * of the dictionary is passed as prefix, and the second via dictStart + dictSize.
+ * These routines are used only once, in LZ4_decompress_*_continue().
+ */
+LZ4_FORCE_INLINE
+int LZ4_decompress_safe_doubleDict(const char *source, char *dest, int compressedSize, int maxOutputSize,
+                                   size_t prefixSize, const void *dictStart, size_t dictSize)
+{
+    return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize,
+                                  endOnInputSize, decode_full_block, usingExtDict,
+                                  (BYTE *)dest - prefixSize, (const BYTE *)dictStart, dictSize);
+}
+
+LZ4_FORCE_INLINE
+int LZ4_decompress_fast_doubleDict(const char *source, char *dest, int originalSize,
+                                   size_t prefixSize, const void *dictStart, size_t dictSize)
+{
+    return LZ4_decompress_generic(source, dest, 0, originalSize,
+                                  endOnOutputSize, decode_full_block, usingExtDict,
+                                  (BYTE *)dest - prefixSize, (const BYTE *)dictStart, dictSize);
+}
+
+/*===== streaming decompression functions =====*/
+
+LZ4_streamDecode_t *LZ4_createStreamDecode(void)
+{
+    LZ4_streamDecode_t *lz4s = (LZ4_streamDecode_t *)ALLOC_AND_ZERO(sizeof(LZ4_streamDecode_t));
+    LZ4_STATIC_ASSERT(LZ4_STREAMDECODESIZE >= sizeof(LZ4_streamDecode_t_internal)); /* A compilation error here means LZ4_STREAMDECODESIZE is not large enough */
+    return lz4s;
+}
+
+int LZ4_freeStreamDecode(LZ4_streamDecode_t *LZ4_stream)
+{
+    if (LZ4_stream == NULL)
+    {
+        return 0;
+    } /* support free on NULL */
+    FREEMEM(LZ4_stream);
+    return 0;
+}
+
+/*! LZ4_setStreamDecode() :
+ *  Use this function to instruct where to find the dictionary.
+ *  This function is not necessary if previous data is still available where it was decoded.
+ *  Loading a size of 0 is allowed (same effect as no dictionary).
+ * @return : 1 if OK, 0 if error
+ */
+int LZ4_setStreamDecode(LZ4_streamDecode_t *LZ4_streamDecode, const char *dictionary, int dictSize)
+{
+    LZ4_streamDecode_t_internal *lz4sd = &LZ4_streamDecode->internal_donotuse;
+    lz4sd->prefixSize = (size_t)dictSize;
+    lz4sd->prefixEnd = (const BYTE *)dictionary + dictSize;
+    lz4sd->externalDict = NULL;
+    lz4sd->extDictSize = 0;
+    return 1;
+}
+
+/*! LZ4_decoderRingBufferSize() :
+ *  when setting a ring buffer for streaming decompression (optional scenario),
+ *  provides the minimum size of this ring buffer
+ *  to be compatible with any source respecting maxBlockSize condition.
+ *  Note : in a ring buffer scenario,
+ *  blocks are presumed decompressed next to each other.
+ *  When not enough space remains for next block (remainingSize < maxBlockSize),
+ *  decoding resumes from beginning of ring buffer.
+ * @return : minimum ring buffer size,
+ *           or 0 if there is an error (invalid maxBlockSize).
+ */
+int LZ4_decoderRingBufferSize(int maxBlockSize)
+{
+    if (maxBlockSize < 0)
+        return 0;
+    if (maxBlockSize > LZ4_MAX_INPUT_SIZE)
+        return 0;
+    if (maxBlockSize < 16)
+        maxBlockSize = 16;
+    return LZ4_DECODER_RING_BUFFER_SIZE(maxBlockSize);
+}
+
+/*
+*_continue() :
+    These decoding functions allow decompression of multiple blocks in "streaming" mode.
+    Previously decoded blocks must still be available at the memory position where they were decoded.
+    If it's not possible, save the relevant part of decoded data into a safe buffer,
+    and indicate where it stands using LZ4_setStreamDecode()
+*/
+LZ4_FORCE_O2
+int LZ4_decompress_safe_continue(LZ4_streamDecode_t *LZ4_streamDecode, const char *source, char *dest, int compressedSize, int maxOutputSize)
+{
+    LZ4_streamDecode_t_internal *lz4sd = &LZ4_streamDecode->internal_donotuse;
+    int result;
+
+    if (lz4sd->prefixSize == 0)
+    {
+        /* The first call, no dictionary yet. */
+        assert(lz4sd->extDictSize == 0);
+        result = LZ4_decompress_safe(source, dest, compressedSize, maxOutputSize);
+        if (result <= 0)
+            return result;
+        lz4sd->prefixSize = (size_t)result;
+        lz4sd->prefixEnd = (BYTE *)dest + result;
+    }
+    else if (lz4sd->prefixEnd == (BYTE *)dest)
+    {
+        /* They're rolling the current segment. */
+        if (lz4sd->prefixSize >= 64 KB - 1)
+            result = LZ4_decompress_safe_withPrefix64k(source, dest, compressedSize, maxOutputSize);
+        else if (lz4sd->extDictSize == 0)
+            result = LZ4_decompress_safe_withSmallPrefix(source, dest, compressedSize, maxOutputSize,
+                                                         lz4sd->prefixSize);
+        else
+            result = LZ4_decompress_safe_doubleDict(source, dest, compressedSize, maxOutputSize,
+                                                    lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize);
+        if (result <= 0)
+            return result;
+        lz4sd->prefixSize += (size_t)result;
+        lz4sd->prefixEnd += result;
+    }
+    else
+    {
+        /* The buffer wraps around, or they're switching to another buffer. */
+        lz4sd->extDictSize = lz4sd->prefixSize;
+        lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
+        result = LZ4_decompress_safe_forceExtDict(source, dest, compressedSize, maxOutputSize,
+                                                  lz4sd->externalDict, lz4sd->extDictSize);
+        if (result <= 0)
+            return result;
+        lz4sd->prefixSize = (size_t)result;
+        lz4sd->prefixEnd = (BYTE *)dest + result;
+    }
+
+    return result;
+}
+
+LZ4_FORCE_O2
+int LZ4_decompress_fast_continue(LZ4_streamDecode_t *LZ4_streamDecode, const char *source, char *dest, int originalSize)
+{
+    LZ4_streamDecode_t_internal *lz4sd = &LZ4_streamDecode->internal_donotuse;
+    int result;
+    assert(originalSize >= 0);
+
+    if (lz4sd->prefixSize == 0)
+    {
+        assert(lz4sd->extDictSize == 0);
+        result = LZ4_decompress_fast(source, dest, originalSize);
+        if (result <= 0)
+            return result;
+        lz4sd->prefixSize = (size_t)originalSize;
+        lz4sd->prefixEnd = (BYTE *)dest + originalSize;
+    }
+    else if (lz4sd->prefixEnd == (BYTE *)dest)
+    {
+        if (lz4sd->prefixSize >= 64 KB - 1 || lz4sd->extDictSize == 0)
+            result = LZ4_decompress_fast(source, dest, originalSize);
+        else
+            result = LZ4_decompress_fast_doubleDict(source, dest, originalSize,
+                                                    lz4sd->prefixSize, lz4sd->externalDict, lz4sd->extDictSize);
+        if (result <= 0)
+            return result;
+        lz4sd->prefixSize += (size_t)originalSize;
+        lz4sd->prefixEnd += originalSize;
+    }
+    else
+    {
+        lz4sd->extDictSize = lz4sd->prefixSize;
+        lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
+        result = LZ4_decompress_fast_extDict(source, dest, originalSize,
+                                             lz4sd->externalDict, lz4sd->extDictSize);
+        if (result <= 0)
+            return result;
+        lz4sd->prefixSize = (size_t)originalSize;
+        lz4sd->prefixEnd = (BYTE *)dest + originalSize;
+    }
+
+    return result;
+}
+
+/*
+Advanced decoding functions :
+*_usingDict() :
+    These decoding functions work the same as "_continue" ones,
+    the dictionary must be explicitly provided within parameters
+*/
+
+int LZ4_decompress_safe_usingDict(const char *source, char *dest, int compressedSize, int maxOutputSize, const char *dictStart, int dictSize)
+{
+    if (dictSize == 0)
+        return LZ4_decompress_safe(source, dest, compressedSize, maxOutputSize);
+    if (dictStart + dictSize == dest)
+    {
+        if (dictSize >= 64 KB - 1)
+        {
+            return LZ4_decompress_safe_withPrefix64k(source, dest, compressedSize, maxOutputSize);
+        }
+        assert(dictSize >= 0);
+        return LZ4_decompress_safe_withSmallPrefix(source, dest, compressedSize, maxOutputSize, (size_t)dictSize);
+    }
+    assert(dictSize >= 0);
+    return LZ4_decompress_safe_forceExtDict(source, dest, compressedSize, maxOutputSize, dictStart, (size_t)dictSize);
+}
+
+int LZ4_decompress_fast_usingDict(const char *source, char *dest, int originalSize, const char *dictStart, int dictSize)
+{
+    if (dictSize == 0 || dictStart + dictSize == dest)
+        return LZ4_decompress_fast(source, dest, originalSize);
+    assert(dictSize >= 0);
+    return LZ4_decompress_fast_extDict(source, dest, originalSize, dictStart, (size_t)dictSize);
+}
+
+/*=*************************************************
+ *  Obsolete Functions
+ ***************************************************/
+/* obsolete compression functions */
+int LZ4_compress_limitedOutput(const char *source, char *dest, int inputSize, int maxOutputSize)
+{
+    return LZ4_compress_default(source, dest, inputSize, maxOutputSize);
+}
+int LZ4_compress(const char *src, char *dest, int srcSize)
+{
+    return LZ4_compress_default(src, dest, srcSize, LZ4_compressBound(srcSize));
+}
+int LZ4_compress_limitedOutput_withState(void *state, const char *src, char *dst, int srcSize, int dstSize)
+{
+    return LZ4_compress_fast_extState(state, src, dst, srcSize, dstSize, 1);
+}
+int LZ4_compress_withState(void *state, const char *src, char *dst, int srcSize)
+{
+    return LZ4_compress_fast_extState(state, src, dst, srcSize, LZ4_compressBound(srcSize), 1);
+}
+int LZ4_compress_limitedOutput_continue(LZ4_stream_t *LZ4_stream, const char *src, char *dst, int srcSize, int dstCapacity)
+{
+    return LZ4_compress_fast_continue(LZ4_stream, src, dst, srcSize, dstCapacity, 1);
+}
+int LZ4_compress_continue(LZ4_stream_t *LZ4_stream, const char *source, char *dest, int inputSize)
+{
+    return LZ4_compress_fast_continue(LZ4_stream, source, dest, inputSize, LZ4_compressBound(inputSize), 1);
+}
+
+/*
+These decompression functions are deprecated and should no longer be used.
+They are only provided here for compatibility with older user programs.
+- LZ4_uncompress is totally equivalent to LZ4_decompress_fast
+- LZ4_uncompress_unknownOutputSize is totally equivalent to LZ4_decompress_safe
+*/
+int LZ4_uncompress(const char *source, char *dest, int outputSize)
+{
+    return LZ4_decompress_fast(source, dest, outputSize);
+}
+int LZ4_uncompress_unknownOutputSize(const char *source, char *dest, int isize, int maxOutputSize)
+{
+    return LZ4_decompress_safe(source, dest, isize, maxOutputSize);
+}
+
+/* Obsolete Streaming functions */
+
+int LZ4_sizeofStreamState(void) { return LZ4_STREAMSIZE; }
+
+int LZ4_resetStreamState(void *state, char *inputBuffer)
+{
+    (void)inputBuffer;
+    LZ4_resetStream((LZ4_stream_t *)state);
+    return 0;
+}
+
+void *LZ4_create(char *inputBuffer)
+{
+    (void)inputBuffer;
+    return LZ4_createStream();
+}
+
+char *LZ4_slideInputBuffer(void *state)
+{
+    /* avoid const char * -> char * conversion warning */
+    return (char *)(uptrval)((LZ4_stream_t *)state)->internal_donotuse.dictionary;
+}
+
+#endif /* LZ4_COMMONDEFS_ONLY */

kernel/process/process.c

@@ -24,6 +24,8 @@
 
 #include <mm/mmio.h>
 
+#include <common/lz4.h>
+
 // #pragma GCC push_options
 // #pragma GCC optimize("O0")
 
@@ -462,6 +464,7 @@ ul initial_kernel_thread(ul arg)
     // kinfo("initial proc running...\targ:%#018lx", arg);
     fat32_init();
     usb_init();
+    kinfo("LZ4 lib Version=%s", LZ4_versionString());
 
     // 对一些组件进行单元测试
     uint64_t tpid[] = {
@@ -1152,9 +1155,11 @@ int process_fd_alloc(struct vfs_file_t *file)
     int fd_num = -1;
     struct vfs_file_t **f = current_pcb->fds;
 
-    for (int i = 0; i < PROC_MAX_FD_NUM; ++i) {
+    for (int i = 0; i < PROC_MAX_FD_NUM; ++i)
+    {
         /* 找到指针数组中的空位 */
-        if (f[i] == NULL) {
+        if (f[i] == NULL)
+        {
             fd_num = i;
             f[i] = file;
             break;