This function discards any unprocessed input and does not flush any   pending output.     deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the   stream state was inconsistent, Z_DATA_ERROR if the stream was freed   prematurely (some input or output was discarded). In the error case,   msg may be set but then points to a static string (which must not be   deallocated).*//*ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));     Initializes the internal stream state for decompression. The fields   next_in, avail_in, zalloc, zfree and opaque must be initialized before by   the caller. If next_in is not Z_NULL and avail_in is large enough (the exact   value depends on the compression method), inflateInit determines the   compression method from the zlib header and allocates all data structures   accordingly; otherwise the allocation will be deferred to the first call of   inflate.  If zalloc and zfree are set to Z_NULL, inflateInit updates them to   use default allocation functions.     inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough   memory, Z_VERSION_ERROR if the zlib library version is incompatible with the   version assumed by the caller.  msg is set to null if there is no error   message. inflateInit does not perform any decompression apart from reading   the zlib header if present: this will be done by inflate().  (So next_in and   avail_in may be modified, but next_out and avail_out are unchanged.)*/ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));/*    inflate decompresses as much data as possible, and stops when the input  buffer becomes empty or the output buffer becomes full. It may introduce  some output latency (reading input without producing any output) except when  forced to flush.  The detailed semantics are as follows. inflate performs one or both of the  following actions:  - Decompress more input starting at next_in and update next_in and avail_in    accordingly. If not all input can be processed (because there is not    enough room in the output buffer), next_in is updated and processing    will resume at this point for the next call of inflate().  - Provide more output starting at next_out and update next_out and avail_out    accordingly.  inflate() provides as much output as possible, until there    is no more input data or no more space in the output buffer (see below    about the flush parameter).  Before the call of inflate(), the application should ensure that at least  one of the actions is possible, by providing more input and/or consuming  more output, and updating the next_* and avail_* values accordingly.  The application can consume the uncompressed output when it wants, for  example when the output buffer is full (avail_out == 0), or after each  call of inflate(). If inflate returns Z_OK and with zero avail_out, it  must be called again after making room in the output buffer because there  might be more output pending.    The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,  Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much  output as possible to the output buffer. Z_BLOCK requests that inflate() stop  if and when it get to the next deflate block boundary. When decoding the zlib  or gzip format, this will cause inflate() to return immediately after the  header and before the first block. When doing a raw inflate, inflate() will  go ahead and process the first block, and will return when it gets to the end  of that block, or when it runs out of data.    The Z_BLOCK option assists in appending to or combining deflate streams.  Also to assist in this, on return inflate() will set strm->data_type to the  number of unused bits in the last byte taken from strm->next_in, plus 64  if inflate() is currently decoding the last block in the deflate stream,  plus 128 if inflate() returned immediately after decoding an end-of-block  code or decoding the complete header up to just before the first byte of the  deflate stream. The end-of-block will not be indicated until all of the  uncompressed data from that block has been written to strm->next_out.  The  number of unused bits may in general be greater than seven, except when  bit 7 of data_type is set, in which case the number of unused bits will be  less than eight.    inflate() should normally be called until it returns Z_STREAM_END or an  error. However if all decompression is to be performed in a single step  (a single call of inflate), the parameter flush should be set to  Z_FINISH. In this case all pending input is processed and all pending  output is flushed; avail_out must be large enough to hold all the  uncompressed data. (The size of the uncompressed data may have been saved  by the compressor for this purpose.) The next operation on this stream must  be inflateEnd to deallocate the decompression state. The use of Z_FINISH  is never required, but can be used to inform inflate that a faster approach  may be used for the single inflate() call.     In this implementation, inflate() always flushes as much output as  possible to the output buffer, and always uses the faster approach on the  first call. So the only effect of the flush parameter in this implementation  is on the return value of inflate(), as noted below, or when it returns early  because Z_BLOCK is used.     If a preset dictionary is needed after this call (see inflateSetDictionary  below), inflate sets strm->adler to the adler32 checksum of the dictionary  chosen by the compressor and returns Z_NEED_DICT; otherwise it sets  strm->adler to the adler32 checksum of all output produced so far (that is,  total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described  below. At the end of the stream, inflate() checks that its computed adler32  checksum is equal to that saved by the compressor and returns Z_STREAM_END  only if the checksum is correct.    inflate() will decompress and check either zlib-wrapped or gzip-wrapped  deflate data.  The header type is detected automatically.  Any information  contained in the gzip header is not retained, so applications that need that  information should instead use raw inflate, see inflateInit2() below, or  inflateBack() and perform their own processing of the gzip header and  trailer.    inflate() returns Z_OK if some progress has been made (more input processed  or more output produced), Z_STREAM_END if the end of the compressed data has  been reached and all uncompressed output has been produced, Z_NEED_DICT if a  preset dictionary is needed at this point, Z_DATA_ERROR if the input data was  corrupted (input stream not conforming to the zlib format or incorrect check  value), Z_STREAM_ERROR if the stream structure was inconsistent (for example  if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,  Z_BUF_ERROR if no progress is possible or if there was not enough room in the  output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and  inflate() can be called again with more input and more output space to  continue decompressing. If Z_DATA_ERROR is returned, the application may then  call inflateSync() to look for a good compression block if a partial recovery  of the data is desired.*/ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));/*     All dynamically allocated data structures for this stream are freed.   This function discards any unprocessed input and does not flush any   pending output.     inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state   was inconsistent. In the error case, msg may be set but then points to a   static string (which must not be deallocated).*/                        /* Advanced functions *//*    The following functions are needed only in some special applications.*//*ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,                                     int  level,                                     int  method,                                     int  windowBits,                                     int  memLevel,                                     int  strategy));     This is another version of deflateInit with more compression options. The   fields next_in, zalloc, zfree and opaque must be initialized before by   the caller.     The method parameter is the compression method. It must be Z_DEFLATED in   this version of the library.     The windowBits parameter is the base two logarithm of the window size   (the size of the history buffer). It should be in the range 8..15 for this   version of the library. Larger values of this parameter result in better   compression at the expense of memory usage. The default value is 15 if   deflateInit is used instead.     windowBits can also be -8..-15 for raw deflate. In this case, -windowBits   determines the window size. deflate() will then generate raw deflate data   with no zlib header or trailer, and will not compute an adler32 check value.     windowBits can also be greater than 15 for optional gzip encoding. Add   16 to windowBits to write a simple gzip header and trailer around the   compressed data instead of a zlib wrapper. The gzip header will have no   file name, no extra data, no comment, no modification time (set to zero),   no header crc, and the operating system will be set to 255 (unknown).  If a   gzip stream is being written, strm->adler is a crc32 instead of an adler32.     The memLevel parameter specifies how much memory should be allocated   for the internal compression state. memLevel=1 uses minimum memory but   is slow and reduces compression ratio; memLevel=9 uses maximum memory   for optimal speed. The default value is 8. See zconf.h for total memory   usage as a function of windowBits and memLevel.     The strategy parameter is used to tune the compression algorithm. Use the   value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a   filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no   string match), or Z_RLE to limit match distances to one (run-length   encoding). Filtered data consists mostly of small values with a somewhat   random distribution. In this case, the compression algorithm is tuned to   compress them better. The effect of Z_FILTERED is to force more Huffman   coding and less string matching; it is somewhat intermediate between   Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as   Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy   parameter only affects the compression ratio but not the correctness of the   compressed output even if it is not set appropriately.      deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough   memory, Z_STREAM_ERROR if a parameter is invalid (such as an invalid   method). msg is set to null if there is no error message.  deflateInit2 does   not perform any compression: this will be done by deflate().*/ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,                                             const Bytef *dictionary,                                             uInt  dictLength));/*     Initializes the compression dictionary from the given byte sequence   without producing any compressed output. This function must be called   immediately after deflateInit, deflateInit2 or deflateReset, before any   call of deflate. The compressor and decompressor must use exactly the same   dictionary (see inflateSetDictionary).     The dictionary should consist of strings (byte sequences) that are likely   to be encountered later in the data to be compressed, with the most commonly   used strings preferably put towards the end of the dictionary. Using a   dictionary is most useful when the data to be compressed is short and can be   predicted with good accuracy; the data can then be compressed better than   with the default empty dictionary.     Depending on the size of the compression data structures selected by   deflateInit or deflateInit2, a part of the dictionary may in effect be   discarded, for example if the dictionary is larger than the window size in   deflate or deflate2. Thus the strings most likely to be useful should be   put at the end of the dictionary, not at the front.     Upon return of this function, strm->adler is set to the adler32 value   of the dictionary; the decompressor may later use this value to determine   which dictionary has been used by the compressor. (The adler32 value   applies to the whole dictionary even if only a subset of the dictionary is   actually used by the compressor.) If a raw deflate was requested, then the   adler32 value is not computed and strm->adler is not set.     deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a   parameter is invalid (such as NULL dictionary) or the stream state is   inconsistent (for example if deflate has already been called for this stream   or if the compression method is bsort). deflateSetDictionary does not   perform any compression: this will be done by deflate().*/ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,                                    z_streamp source));/*     Sets the destination stream as a complete copy of the source stream.     This function can be useful when several compression strategies will be   tried, for example when there are several ways of pre-processing the input   data with a filter. The streams that will be discarded should then be freed   by calling deflateEnd.  Note that deflateCopy duplicates the internal   compression state which can be quite large, so this strategy is slow and   can consume lots of memory.     deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not   enough memory, Z_STREAM_ERROR if the source stream state was inconsistent   (such as zalloc being NULL). msg is left unchanged in both source and   destination.*/ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));/*     This function is equivalent to deflateEnd followed by deflateInit,   but does not free and reallocate all the internal compression state.   The stream will keep the same compression level and any other attributes   that may have been set by deflateInit2.      deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source   stream state was inconsistent (such as zalloc or state being NULL).*/ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,                                      int level,                                      int strategy));/*     Dynamically update the compression level and compression strategy.  The   interpretation of level and strategy is as in deflateInit2.  This can be   used to switch between compression and straight copy of the input data, or   to switch to a different kind of input data requiring a different   strategy. If the compression level is changed, the input available so far   is compressed with the old level (and may be flushed); the new level will   take effect only at the next call of deflate().     Before the call of deflateParams, the stream state must be set as for   a call of deflate(), since the currently available input may have to   be compressed and flushed. In particular, strm->avail_out must be non-zero.     deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source   stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR   if strm->avail_out was zero.*/ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,                                       uLong sourceLen));/*     deflateBound() returns an upper bound on the compressed size after   deflation of sourceLen bytes.  It must be called after deflateInit()   or deflateInit2().  This would be used to allocate an output buffer   for deflation in a single pass, and so would be called before deflate().*/