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+/*
+ LZ4 - Fast LZ compression algorithm
+ Header File
+ Copyright (C) 2011-2014, 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 source repository : http://code.google.com/p/lz4/
+ - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
+*/
+#pragma once
+
+#if defined (__cplusplus)
+extern "C" {
+#endif
+
+
+/**************************************
+ Version
+**************************************/
+#define LZ4_VERSION_MAJOR 1 /* for major interface/format changes */
+#define LZ4_VERSION_MINOR 2 /* for minor interface/format changes */
+#define LZ4_VERSION_RELEASE 0 /* for tweaks, bug-fixes, or development */
+
+
+/**************************************
+ 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 can improve speed, due to cache effect
+ * Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
+ */
+#define LZ4_MEMORY_USAGE 14
+
+
+/**************************************
+ Simple Functions
+**************************************/
+
+int LZ4_compress (const char* source, char* dest, int inputSize);
+int LZ4_decompress_safe (const char* source, char* dest, int compressedSize, int maxOutputSize);
+
+/*
+LZ4_compress() :
+ Compresses 'inputSize' bytes from 'source' into 'dest'.
+ Destination buffer must be already allocated,
+ and must be sized to handle worst cases situations (input data not compressible)
+ Worst case size evaluation is provided by function LZ4_compressBound()
+ inputSize : Max supported value is LZ4_MAX_INPUT_VALUE
+ return : the number of bytes written in buffer dest
+ or 0 if the compression fails
+
+LZ4_decompress_safe() :
+ compressedSize : is obviously the source size
+ maxOutputSize : is the size of the destination buffer, which must be already allocated.
+ return : the number of bytes decoded in the destination buffer (necessarily <= maxOutputSize)
+ If the destination buffer is not large enough, decoding will stop and output an error code (<0).
+ If the source stream is detected malformed, the function will stop decoding and return a negative result.
+ This function is protected against buffer overflow exploits :
+ it never writes outside of output buffer, and never reads outside of input buffer.
+ Therefore, it is protected against malicious data packets.
+*/
+
+
+/*
+Note :
+ Should you prefer to explicitly allocate compression-table memory using your own allocation method,
+ use the streaming functions provided below, simply reset the memory area between each call to LZ4_compress_continue()
+*/
+
+
+/**************************************
+ Advanced Functions
+**************************************/
+#define LZ4_MAX_INPUT_SIZE 0x7E000000 /* 2 113 929 216 bytes */
+#define LZ4_COMPRESSBOUND(isize) ((unsigned int)(isize) > (unsigned int)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16)
+
+/*
+LZ4_compressBound() :
+ Provides the maximum size that LZ4 may output in a "worst case" scenario (input data not compressible)
+ primarily useful for memory allocation of output buffer.
+ macro is also provided when result needs to be evaluated at compilation (such as stack memory allocation).
+
+ isize : is the input size. Max supported value is LZ4_MAX_INPUT_SIZE
+ return : maximum output size in a "worst case" scenario
+ or 0, if input size is too large ( > LZ4_MAX_INPUT_SIZE)
+*/
+int LZ4_compressBound(int isize);
+
+
+/*
+LZ4_compress_limitedOutput() :
+ Compress 'inputSize' bytes from 'source' into an output buffer 'dest' of maximum size 'maxOutputSize'.
+ If it cannot achieve it, compression will stop, and result of the function will be zero.
+ This function never writes outside of provided output buffer.
+
+ inputSize : Max supported value is LZ4_MAX_INPUT_VALUE
+ maxOutputSize : is the size of the destination buffer (which must be already allocated)
+ return : the number of bytes written in buffer 'dest'
+ or 0 if the compression fails
+*/
+int LZ4_compress_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize);
+
+
+/*
+LZ4_decompress_fast() :
+ originalSize : is the original and therefore uncompressed size
+ return : the number of bytes read from the source buffer (in other words, the compressed size)
+ If the source stream is malformed, the function will stop decoding and return a negative result.
+ Destination buffer must be already allocated. Its size must be a minimum of 'originalSize' bytes.
+ note : This function is a bit faster than LZ4_decompress_safe()
+ It provides fast decompression and fully respect memory boundaries for properly formed compressed data.
+ It does not provide full protection against intentionnally modified data stream.
+ Use this function in a trusted environment (data to decode comes from a trusted source).
+*/
+int LZ4_decompress_fast (const char* source, char* dest, int originalSize);
+
+
+/*
+LZ4_decompress_safe_partial() :
+ This function decompress a compressed block of size 'compressedSize' at position 'source'
+ into output buffer 'dest' of size 'maxOutputSize'.
+ The function tries to stop decompressing operation as soon as 'targetOutputSize' has been reached,
+ reducing decompression time.
+ return : the number of bytes decoded in the destination buffer (necessarily <= maxOutputSize)
+ Note : this number can be < 'targetOutputSize' should the compressed block to decode be smaller.
+ Always control how many bytes were decoded.
+ If the source stream is detected malformed, the function will stop decoding and return a negative result.
+ This function never writes outside of output buffer, and never reads outside of input buffer. It is therefore protected against malicious data packets
+*/
+int LZ4_decompress_safe_partial (const char* source, char* dest, int compressedSize, int targetOutputSize, int maxOutputSize);
+
+
+/***********************************************
+ Experimental Streaming Compression Functions
+***********************************************/
+
+#define LZ4_STREAMSIZE_U32 ((1 << (LZ4_MEMORY_USAGE-2)) + 8)
+#define LZ4_STREAMSIZE (LZ4_STREAMSIZE_U32 * sizeof(unsigned int))
+/*
+ * LZ4_stream_t
+ * information structure to track an LZ4 stream.
+ * important : set this structure content to zero before first use !
+ */
+typedef struct { unsigned int table[LZ4_STREAMSIZE_U32]; } LZ4_stream_t;
+
+/*
+ * If you prefer dynamic allocation methods,
+ * LZ4_createStream
+ * provides a pointer (void*) towards an initialized LZ4_stream_t structure.
+ * LZ4_free just frees it.
+ */
+void* LZ4_createStream();
+int LZ4_free (void* LZ4_stream);
+
+
+/*
+ * LZ4_loadDict
+ * Use this function to load a static dictionary into LZ4_stream.
+ * Any previous data will be forgotten, only 'dictionary' will remain in memory.
+ * Loading a size of 0 is allowed (same effect as init).
+ * Return : 1 if OK, 0 if error
+ */
+int LZ4_loadDict (void* LZ4_stream, const char* dictionary, int dictSize);
+
+/*
+ * LZ4_compress_continue
+ * Compress data block 'source', using blocks compressed before as dictionary to improve compression ratio
+ * Previous data blocks are assumed to still be present at their previous location.
+ */
+int LZ4_compress_continue (void* LZ4_stream, const char* source, char* dest, int inputSize);
+
+/*
+ * LZ4_compress_limitedOutput_continue
+ * Same as before, but also specify a maximum target compressed size (maxOutputSize)
+ * If objective cannot be met, compression exits, and returns a zero.
+ */
+int LZ4_compress_limitedOutput_continue (void* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize);
+
+/*
+ * LZ4_saveDict
+ * If previously compressed data block is not guaranteed to remain at its previous memory location
+ * save it into a safe place (char* safeBuffer)
+ * Note : you don't need to call LZ4_loadDict() afterwards,
+ * dictionary is immediately usable, you can therefore call again LZ4_compress_continue()
+ * Return : 1 if OK, 0 if error
+ * Note : any dictSize > 64 KB will be interpreted as 64KB.
+ */
+int LZ4_saveDict (void* LZ4_stream, char* safeBuffer, int dictSize);
+
+
+/************************************************
+ Experimental Streaming Decompression Functions
+************************************************/
+
+#define LZ4_STREAMDECODESIZE_U32 4
+#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U32 * sizeof(unsigned int))
+/*
+ * LZ4_streamDecode_t
+ * information structure to track an LZ4 stream.
+ * important : set this structure content to zero before first use !
+ */
+typedef struct { unsigned int table[LZ4_STREAMDECODESIZE_U32]; } LZ4_streamDecode_t;
+
+/*
+ * If you prefer dynamic allocation methods,
+ * LZ4_createStreamDecode()
+ * provides a pointer (void*) towards an initialized LZ4_streamDecode_t structure.
+ * LZ4_free just frees it.
+ */
+void* LZ4_createStreamDecode();
+int LZ4_free (void* LZ4_stream); /* yes, it's the same one as for compression */
+
+/*
+*_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_setDictDecode()
+*/
+int LZ4_decompress_safe_continue (void* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxOutputSize);
+int LZ4_decompress_fast_continue (void* LZ4_streamDecode, const char* source, char* dest, int originalSize);
+
+/*
+ * LZ4_setDictDecode
+ * Use this function to instruct where to find the dictionary.
+ * This function can be used to specify a static dictionary,
+ * or to instruct where to find some previously decoded data saved into a different memory space.
+ * Setting a size of 0 is allowed (same effect as no dictionary).
+ * Return : 1 if OK, 0 if error
+ */
+int LZ4_setDictDecode (void* LZ4_streamDecode, const char* dictionary, int dictSize);
+
+
+/*
+Advanced decoding functions :
+*_usingDict() :
+ These decoding functions work the same as
+ a combination of LZ4_setDictDecode() followed by LZ4_decompress_x_continue()
+ all together into a single function call.
+ It doesn't use nor update an LZ4_streamDecode_t structure.
+*/
+int LZ4_decompress_safe_usingDict (const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize);
+int LZ4_decompress_fast_usingDict (const char* source, char* dest, int originalSize, const char* dictStart, int dictSize);
+
+
+
+#if defined (__cplusplus)
+}
+#endif