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+/* zlib.h -- interface of the 'zlib' general purpose compression library
+
+ Copyright (C) 1995-2005 Jean-loup Gailly and Mark Adler
+
+ This software is provided 'as-is', without any express or implied
+ warranty. In no event will the authors be held liable for any damages
+ arising from the use of this software.
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute it
+ freely, subject to the following restrictions:
+
+ 1. The origin of this software must not be misrepresented; you must not
+ claim that you wrote the original software. If you use this software
+ in a product, an acknowledgment in the product documentation would be
+ appreciated but is not required.
+ 2. Altered source versions must be plainly marked as such, and must not be
+ misrepresented as being the original software.
+ 3. This notice may not be removed or altered from any source distribution.
+
+ Jean-loup Gailly Mark Adler
+ jloup@gzip.org madler@alumni.caltech.edu
+
+
+ The data format used by the zlib library is described by RFCs (Request for
+ Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
+ (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
+*/
+
+#ifndef _ZLIB_H
+#define _ZLIB_H
+
+#include <linux/zconf.h>
+
+/* zlib deflate based on ZLIB_VERSION "1.1.3" */
+/* zlib inflate based on ZLIB_VERSION "1.2.3" */
+
+/*
+ This is a modified version of zlib for use inside the Linux kernel.
+ The main changes are to perform all memory allocation in advance.
+
+ Inflation Changes:
+ * Z_PACKET_FLUSH is added and used by ppp_deflate. Before returning
+ this checks there is no more input data available and the next data
+ is a STORED block. It also resets the mode to be read for the next
+ data, all as per PPP requirements.
+ * Addition of zlib_inflateIncomp which copies incompressible data into
+ the history window and adjusts the accoutning without calling
+ zlib_inflate itself to inflate the data.
+*/
+
+/*
+ The 'zlib' compression library provides in-memory compression and
+ decompression functions, including integrity checks of the uncompressed
+ data. This version of the library supports only one compression method
+ (deflation) but other algorithms will be added later and will have the same
+ stream interface.
+
+ Compression can be done in a single step if the buffers are large
+ enough (for example if an input file is mmap'ed), or can be done by
+ repeated calls of the compression function. In the latter case, the
+ application must provide more input and/or consume the output
+ (providing more output space) before each call.
+
+ The compressed data format used by default by the in-memory functions is
+ the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
+ around a deflate stream, which is itself documented in RFC 1951.
+
+ The library also supports reading and writing files in gzip (.gz) format
+ with an interface similar to that of stdio.
+
+ The zlib format was designed to be compact and fast for use in memory
+ and on communications channels. The gzip format was designed for single-
+ file compression on file systems, has a larger header than zlib to maintain
+ directory information, and uses a different, slower check method than zlib.
+
+ The library does not install any signal handler. The decoder checks
+ the consistency of the compressed data, so the library should never
+ crash even in case of corrupted input.
+*/
+
+struct internal_state;
+
+typedef struct z_stream_s {
+ const Byte *next_in; /* next input byte */
+ uLong avail_in; /* number of bytes available at next_in */
+ uLong total_in; /* total nb of input bytes read so far */
+
+ Byte *next_out; /* next output byte should be put there */
+ uLong avail_out; /* remaining free space at next_out */
+ uLong total_out; /* total nb of bytes output so far */
+
+ char *msg; /* last error message, NULL if no error */
+ struct internal_state *state; /* not visible by applications */
+
+ void *workspace; /* memory allocated for this stream */
+
+ int data_type; /* best guess about the data type: ascii or binary */
+ uLong adler; /* adler32 value of the uncompressed data */
+ uLong reserved; /* reserved for future use */
+} z_stream;
+
+typedef z_stream *z_streamp;
+
+/*
+ The application must update next_in and avail_in when avail_in has
+ dropped to zero. It must update next_out and avail_out when avail_out
+ has dropped to zero. The application must initialize zalloc, zfree and
+ opaque before calling the init function. All other fields are set by the
+ compression library and must not be updated by the application.
+
+ The opaque value provided by the application will be passed as the first
+ parameter for calls of zalloc and zfree. This can be useful for custom
+ memory management. The compression library attaches no meaning to the
+ opaque value.
+
+ zalloc must return NULL if there is not enough memory for the object.
+ If zlib is used in a multi-threaded application, zalloc and zfree must be
+ thread safe.
+
+ On 16-bit systems, the functions zalloc and zfree must be able to allocate
+ exactly 65536 bytes, but will not be required to allocate more than this
+ if the symbol MAXSEG_64K is defined (see zconf.h). WARNING: On MSDOS,
+ pointers returned by zalloc for objects of exactly 65536 bytes *must*
+ have their offset normalized to zero. The default allocation function
+ provided by this library ensures this (see zutil.c). To reduce memory
+ requirements and avoid any allocation of 64K objects, at the expense of
+ compression ratio, compile the library with -DMAX_WBITS=14 (see zconf.h).
+
+ The fields total_in and total_out can be used for statistics or
+ progress reports. After compression, total_in holds the total size of
+ the uncompressed data and may be saved for use in the decompressor
+ (particularly if the decompressor wants to decompress everything in
+ a single step).
+*/
+
+ /* constants */
+
+#define Z_NO_FLUSH 0
+#define Z_PARTIAL_FLUSH 1 /* will be removed, use Z_SYNC_FLUSH instead */
+#define Z_PACKET_FLUSH 2
+#define Z_SYNC_FLUSH 3
+#define Z_FULL_FLUSH 4
+#define Z_FINISH 5
+#define Z_BLOCK 6 /* Only for inflate at present */
+/* Allowed flush values; see deflate() and inflate() below for details */
+
+#define Z_OK 0
+#define Z_STREAM_END 1
+#define Z_NEED_DICT 2
+#define Z_ERRNO (-1)
+#define Z_STREAM_ERROR (-2)
+#define Z_DATA_ERROR (-3)
+#define Z_MEM_ERROR (-4)
+#define Z_BUF_ERROR (-5)
+#define Z_VERSION_ERROR (-6)
+/* Return codes for the compression/decompression functions. Negative
+ * values are errors, positive values are used for special but normal events.
+ */
+
+#define Z_NO_COMPRESSION 0
+#define Z_BEST_SPEED 1
+#define Z_BEST_COMPRESSION 9
+#define Z_DEFAULT_COMPRESSION (-1)
+/* compression levels */
+
+#define Z_FILTERED 1
+#define Z_HUFFMAN_ONLY 2
+#define Z_DEFAULT_STRATEGY 0
+/* compression strategy; see deflateInit2() below for details */
+
+#define Z_BINARY 0
+#define Z_ASCII 1
+#define Z_UNKNOWN 2
+/* Possible values of the data_type field */
+
+#define Z_DEFLATED 8
+/* The deflate compression method (the only one supported in this version) */
+
+ /* basic functions */
+
+extern int zlib_deflate_workspacesize (int windowBits, int memLevel);
+/*
+ Returns the number of bytes that needs to be allocated for a per-
+ stream workspace with the specified parameters. A pointer to this
+ number of bytes should be returned in stream->workspace before
+ you call zlib_deflateInit() or zlib_deflateInit2(). If you call
+ zlib_deflateInit(), specify windowBits = MAX_WBITS and memLevel =
+ MAX_MEM_LEVEL here. If you call zlib_deflateInit2(), the windowBits
+ and memLevel parameters passed to zlib_deflateInit2() must not
+ exceed those passed here.
+*/
+
+/*
+extern int deflateInit (z_streamp strm, int level);
+
+ Initializes the internal stream state for compression. The fields
+ zalloc, zfree and opaque must be initialized before by the caller.
+ If zalloc and zfree are set to NULL, deflateInit updates them to
+ use default allocation functions.
+
+ The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
+ 1 gives best speed, 9 gives best compression, 0 gives no compression at
+ all (the input data is simply copied a block at a time).
+ Z_DEFAULT_COMPRESSION requests a default compromise between speed and
+ compression (currently equivalent to level 6).
+
+ deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
+ enough memory, Z_STREAM_ERROR if level is not a valid compression level,
+ Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
+ with the version assumed by the caller (ZLIB_VERSION).
+ msg is set to null if there is no error message. deflateInit does not
+ perform any compression: this will be done by deflate().
+*/
+
+
+extern int zlib_deflate (z_streamp strm, int flush);
+/*
+ deflate compresses 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. deflate performs one or both of the
+ following actions:
+
+ - Compress 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 and avail_in are updated and
+ processing will resume at this point for the next call of deflate().
+
+ - Provide more output starting at next_out and update next_out and avail_out
+ accordingly. This action is forced if the parameter flush is non zero.
+ Forcing flush frequently degrades the compression ratio, so this parameter
+ should be set only when necessary (in interactive applications).
+ Some output may be provided even if flush is not set.
+
+ Before the call of deflate(), the application should ensure that at least
+ one of the actions is possible, by providing more input and/or consuming
+ more output, and updating avail_in or avail_out accordingly; avail_out
+ should never be zero before the call. The application can consume the
+ compressed output when it wants, for example when the output buffer is full
+ (avail_out == 0), or after each call of deflate(). If deflate 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.
+
+ If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
+ flushed to the output buffer and the output is aligned on a byte boundary, so
+ that the decompressor can get all input data available so far. (In particular
+ avail_in is zero after the call if enough output space has been provided
+ before the call.) Flushing may degrade compression for some compression
+ algorithms and so it should be used only when necessary.
+
+ If flush is set to Z_FULL_FLUSH, all output is flushed as with
+ Z_SYNC_FLUSH, and the compression state is reset so that decompression can
+ restart from this point if previous compressed data has been damaged or if
+ random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
+ the compression.
+
+ If deflate returns with avail_out == 0, this function must be called again
+ with the same value of the flush parameter and more output space (updated
+ avail_out), until the flush is complete (deflate returns with non-zero
+ avail_out).
+
+ If the parameter flush is set to Z_FINISH, pending input is processed,
+ pending output is flushed and deflate returns with Z_STREAM_END if there
+ was enough output space; if deflate returns with Z_OK, this function must be
+ called again with Z_FINISH and more output space (updated avail_out) but no
+ more input data, until it returns with Z_STREAM_END or an error. After
+ deflate has returned Z_STREAM_END, the only possible operations on the
+ stream are deflateReset or deflateEnd.
+
+ Z_FINISH can be used immediately after deflateInit if all the compression
+ is to be done in a single step. In this case, avail_out must be at least
+ 0.1% larger than avail_in plus 12 bytes. If deflate does not return
+ Z_STREAM_END, then it must be called again as described above.
+
+ deflate() sets strm->adler to the adler32 checksum of all input read
+ so far (that is, total_in bytes).
+
+ deflate() may update data_type if it can make a good guess about
+ the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered
+ binary. This field is only for information purposes and does not affect
+ the compression algorithm in any manner.
+
+ deflate() returns Z_OK if some progress has been made (more input
+ processed or more output produced), Z_STREAM_END if all input has been
+ consumed and all output has been produced (only when flush is set to
+ Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
+ if next_in or next_out was NULL), Z_BUF_ERROR if no progress is possible
+ (for example avail_in or avail_out was zero).
+*/
+
+
+extern int zlib_deflateEnd (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.
+
+ 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).
+*/
+
+
+extern int zlib_inflate_workspacesize (void);
+/*
+ Returns the number of bytes that needs to be allocated for a per-
+ stream workspace. A pointer to this number of bytes should be
+ returned in stream->workspace before calling zlib_inflateInit().
+*/
+
+/*
+extern int zlib_inflateInit (z_streamp strm);
+
+ Initializes the internal stream state for decompression. The fields
+ next_in, avail_in, and workspace must be initialized before by
+ the caller. If next_in is not 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 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.)
+*/
+
+
+extern int zlib_inflate (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 gets 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.
+*/
+
+
+extern int zlib_inflateEnd (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.
+*/
+
+/*
+extern int deflateInit2 (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.
+
+ 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), or Z_HUFFMAN_ONLY to force Huffman encoding only (no
+ string match). 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. 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().
+*/
+
+extern int zlib_deflateReset (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).
+*/
+
+static inline unsigned long deflateBound(unsigned long s)
+{
+ return s + ((s + 7) >> 3) + ((s + 63) >> 6) + 11;
+}
+
+/*
+extern int inflateInit2 (z_streamp strm, int windowBits);
+
+ This is another version of inflateInit with an extra parameter. The
+ fields next_in, avail_in, zalloc, zfree and opaque must be initialized
+ before by the caller.
+
+ The windowBits parameter is the base two logarithm of the maximum window
+ size (the size of the history buffer). It should be in the range 8..15 for
+ this version of the library. The default value is 15 if inflateInit is used
+ instead. windowBits must be greater than or equal to the windowBits value
+ provided to deflateInit2() while compressing, or it must be equal to 15 if
+ deflateInit2() was not used. If a compressed stream with a larger window
+ size is given as input, inflate() will return with the error code
+ Z_DATA_ERROR instead of trying to allocate a larger window.
+
+ windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
+ determines the window size. inflate() will then process raw deflate data,
+ not looking for a zlib or gzip header, not generating a check value, and not
+ looking for any check values for comparison at the end of the stream. This
+ is for use with other formats that use the deflate compressed data format
+ such as zip. Those formats provide their own check values. If a custom
+ format is developed using the raw deflate format for compressed data, it is
+ recommended that a check value such as an adler32 or a crc32 be applied to
+ the uncompressed data as is done in the zlib, gzip, and zip formats. For
+ most applications, the zlib format should be used as is. Note that comments
+ above on the use in deflateInit2() applies to the magnitude of windowBits.
+
+ windowBits can also be greater than 15 for optional gzip decoding. Add
+ 32 to windowBits to enable zlib and gzip decoding with automatic header
+ detection, or add 16 to decode only the gzip format (the zlib format will
+ return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is
+ a crc32 instead of an adler32.
+
+ inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
+ memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg
+ is set to null if there is no error message. inflateInit2 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.)
+*/
+
+extern int zlib_inflateReset (z_streamp strm);
+/*
+ This function is equivalent to inflateEnd followed by inflateInit,
+ but does not free and reallocate all the internal decompression state.
+ The stream will keep attributes that may have been set by inflateInit2.
+
+ inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
+ stream state was inconsistent (such as zalloc or state being NULL).
+*/
+
+extern int zlib_inflateIncomp (z_stream *strm);
+/*
+ This function adds the data at next_in (avail_in bytes) to the output
+ history without performing any output. There must be no pending output,
+ and the decompressor must be expecting to see the start of a block.
+ Calling this function is equivalent to decompressing a stored block
+ containing the data at next_in (except that the data is not output).
+*/
+
+#define zlib_deflateInit(strm, level) \
+ zlib_deflateInit2((strm), (level), Z_DEFLATED, MAX_WBITS, \
+ DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY)
+#define zlib_inflateInit(strm) \
+ zlib_inflateInit2((strm), DEF_WBITS)
+
+extern int zlib_deflateInit2(z_streamp strm, int level, int method,
+ int windowBits, int memLevel,
+ int strategy);
+extern int zlib_inflateInit2(z_streamp strm, int windowBits);
+
+#if !defined(_Z_UTIL_H) && !defined(NO_DUMMY_DECL)
+ struct internal_state {int dummy;}; /* hack for buggy compilers */
+#endif
+
+/* Utility function: initialize zlib, unpack binary blob, clean up zlib,
+ * return len or negative error code. */
+extern int zlib_inflate_blob(void *dst, unsigned dst_sz, const void *src, unsigned src_sz);
+
+#endif /* _ZLIB_H */