diff options
| author | Tartalo <none@none> | 2010-06-06 22:37:00 +0200 | 
|---|---|---|
| committer | Tartalo <none@none> | 2010-06-06 22:37:00 +0200 | 
| commit | 12d1becdcf749106af9c5ac3fd2f1c3de42b5584 (patch) | |
| tree | 49fcaf2bfb8a58a8fd092417565ff6036f73e98a /externals/zlib/zlib.h | |
| parent | 1b32fbe085d447caa8145c4c62729462932beafe (diff) | |
| parent | 840d4ab99d270088a225af69562920fdc3043556 (diff) | |
Branch merge
--HG--
branch : trunk
Diffstat (limited to 'externals/zlib/zlib.h')
| -rw-r--r-- | externals/zlib/zlib.h | 1613 | 
1 files changed, 1613 insertions, 0 deletions
| diff --git a/externals/zlib/zlib.h b/externals/zlib/zlib.h new file mode 100644 index 00000000000..bfbba83e8ee --- /dev/null +++ b/externals/zlib/zlib.h @@ -0,0 +1,1613 @@ +/* zlib.h -- interface of the 'zlib' general purpose compression library +  version 1.2.5, April 19th, 2010 + +  Copyright (C) 1995-2010 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 "zconf.h" + +#ifdef __cplusplus +extern "C" { +#endif + +#define ZLIB_VERSION "1.2.5" +#define ZLIB_VERNUM 0x1250 +#define ZLIB_VER_MAJOR 1 +#define ZLIB_VER_MINOR 2 +#define ZLIB_VER_REVISION 5 +#define ZLIB_VER_SUBREVISION 0 + +/* +    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, +  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 using the functions that start +  with "gz".  The gzip format is different from the zlib format.  gzip is a +  gzip wrapper, documented in RFC 1952, wrapped around a deflate stream. + +    This library can optionally read and write gzip streams in memory as well. + +    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. +*/ + +typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size)); +typedef void   (*free_func)  OF((voidpf opaque, voidpf address)); + +struct internal_state; + +typedef struct z_stream_s { +    Bytef    *next_in;  /* next input byte */ +    uInt     avail_in;  /* number of bytes available at next_in */ +    uLong    total_in;  /* total nb of input bytes read so far */ + +    Bytef    *next_out; /* next output byte should be put there */ +    uInt     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 FAR *state; /* not visible by applications */ + +    alloc_func zalloc;  /* used to allocate the internal state */ +    free_func  zfree;   /* used to free the internal state */ +    voidpf     opaque;  /* private data object passed to zalloc and zfree */ + +    int     data_type;  /* best guess about the data type: binary or text */ +    uLong   adler;      /* adler32 value of the uncompressed data */ +    uLong   reserved;   /* reserved for future use */ +} z_stream; + +typedef z_stream FAR *z_streamp; + +/* +     gzip header information passed to and from zlib routines.  See RFC 1952 +  for more details on the meanings of these fields. +*/ +typedef struct gz_header_s { +    int     text;       /* true if compressed data believed to be text */ +    uLong   time;       /* modification time */ +    int     xflags;     /* extra flags (not used when writing a gzip file) */ +    int     os;         /* operating system */ +    Bytef   *extra;     /* pointer to extra field or Z_NULL if none */ +    uInt    extra_len;  /* extra field length (valid if extra != Z_NULL) */ +    uInt    extra_max;  /* space at extra (only when reading header) */ +    Bytef   *name;      /* pointer to zero-terminated file name or Z_NULL */ +    uInt    name_max;   /* space at name (only when reading header) */ +    Bytef   *comment;   /* pointer to zero-terminated comment or Z_NULL */ +    uInt    comm_max;   /* space at comment (only when reading header) */ +    int     hcrc;       /* true if there was or will be a header crc */ +    int     done;       /* true when done reading gzip header (not used +                           when writing a gzip file) */ +} gz_header; + +typedef gz_header FAR *gz_headerp; + +/* +     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 Z_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 +#define Z_SYNC_FLUSH    2 +#define Z_FULL_FLUSH    3 +#define Z_FINISH        4 +#define Z_BLOCK         5 +#define Z_TREES         6 +/* 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_RLE                 3 +#define Z_FIXED               4 +#define Z_DEFAULT_STRATEGY    0 +/* compression strategy; see deflateInit2() below for details */ + +#define Z_BINARY   0 +#define Z_TEXT     1 +#define Z_ASCII    Z_TEXT   /* for compatibility with 1.2.2 and earlier */ +#define Z_UNKNOWN  2 +/* Possible values of the data_type field (though see inflate()) */ + +#define Z_DEFLATED   8 +/* The deflate compression method (the only one supported in this version) */ + +#define Z_NULL  0  /* for initializing zalloc, zfree, opaque */ + +#define zlib_version zlibVersion() +/* for compatibility with versions < 1.0.2 */ + + +                        /* basic functions */ + +ZEXTERN const char * ZEXPORT zlibVersion OF((void)); +/* The application can compare zlibVersion and ZLIB_VERSION for consistency. +   If the first character differs, the library code actually used is not +   compatible with the zlib.h header file used by the application.  This check +   is automatically made by deflateInit and inflateInit. + */ + +/* +ZEXTERN int ZEXPORT deflateInit OF((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 Z_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, or +   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(). +*/ + + +ZEXTERN int ZEXPORT deflate OF((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. + +    Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to +  decide how much data to accumulate before producing output, in order to +  maximize compression. + +    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.  This +  completes the current deflate block and follows it with an empty stored block +  that is three bits plus filler bits to the next byte, followed by four bytes +  (00 00 ff ff). + +    If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the +  output buffer, but the output is not aligned to a byte boundary.  All of the +  input data so far will be available to the decompressor, as for Z_SYNC_FLUSH. +  This completes the current deflate block and follows it with an empty fixed +  codes block that is 10 bits long.  This assures that enough bytes are output +  in order for the decompressor to finish the block before the empty fixed code +  block. + +    If flush is set to Z_BLOCK, a deflate block is completed and emitted, as +  for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to +  seven bits of the current block are held to be written as the next byte after +  the next deflate block is completed.  In this case, the decompressor may not +  be provided enough bits at this point in order to complete decompression of +  the data provided so far to the compressor.  It may need to wait for the next +  block to be emitted.  This is for advanced applications that need to control +  the emission of deflate blocks. + +    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 +  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).  In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that +  avail_out is greater than six to avoid repeated flush markers due to +  avail_out == 0 on return. + +    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 the +  value returned by deflateBound (see below).  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 strm->data_type if it can make a good guess about +  the input data type (Z_BINARY or Z_TEXT).  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 Z_NULL), Z_BUF_ERROR if no progress is possible +  (for example avail_in or avail_out was zero).  Note that Z_BUF_ERROR is not +  fatal, and deflate() can be called again with more input and more output +  space to continue compressing. +*/ + + +ZEXTERN int ZEXPORT deflateEnd 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. + +     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, or Z_STREAM_ERROR if the parameters are +   invalid, such as a null pointer to the structure.  msg is set to null if +   there is no error message.  inflateInit does not perform any decompression +   apart from possibly reading the zlib header if present: actual decompression +   will be done by inflate().  (So next_in and avail_in may be modified, but +   next_out and avail_out are unused and unchanged.) The current implementation +   of inflateInit() does not process any header information -- that is deferred +   until inflate() is called. +*/ + + +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, +  Z_BLOCK, or Z_TREES.  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.  data_type is set as noted here every time inflate() returns for all +  flush options, and so can be used to determine the amount of currently +  consumed input in bits. + +    The Z_TREES option behaves as Z_BLOCK does, but it also returns when the +  end of each deflate block header is reached, before any actual data in that +  block is decoded.  This allows the caller to determine the length of the +  deflate block header for later use in random access within a deflate block. +  256 is added to the value of strm->data_type when inflate() returns +  immediately after reaching the end of the deflate block header. + +    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 or Z_TREES 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() can decompress and check either zlib-wrapped or gzip-wrapped +  deflate data.  The header type is detected automatically, if requested when +  initializing with inflateInit2().  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 +  next_in or next_out was Z_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_STRATEGY 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. +   Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler +   decoder for special applications. + +     deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough +   memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid +   method), or 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.  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 +   provided in deflateInit or deflateInit2.  Thus the strings most likely to be +   useful should be put at the end of the dictionary, not at the front.  In +   addition, the current implementation of deflate will use at most the window +   size minus 262 bytes of the provided dictionary. + +     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 (e.g.  dictionary being Z_NULL) 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 Z_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 Z_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 int ZEXPORT deflateTune OF((z_streamp strm, +                                    int good_length, +                                    int max_lazy, +                                    int nice_length, +                                    int max_chain)); +/* +     Fine tune deflate's internal compression parameters.  This should only be +   used by someone who understands the algorithm used by zlib's deflate for +   searching for the best matching string, and even then only by the most +   fanatic optimizer trying to squeeze out the last compressed bit for their +   specific input data.  Read the deflate.c source code for the meaning of the +   max_lazy, good_length, nice_length, and max_chain parameters. + +     deflateTune() can be called after deflateInit() or deflateInit2(), and +   returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream. + */ + +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(), and after deflateSetHeader(), if used.  This would be used +   to allocate an output buffer for deflation in a single pass, and so would be +   called before deflate(). +*/ + +ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm, +                                     int bits, +                                     int value)); +/* +     deflatePrime() inserts bits in the deflate output stream.  The intent +   is that this function is used to start off the deflate output with the bits +   leftover from a previous deflate stream when appending to it.  As such, this +   function can only be used for raw deflate, and must be used before the first +   deflate() call after a deflateInit2() or deflateReset().  bits must be less +   than or equal to 16, and that many of the least significant bits of value +   will be inserted in the output. + +     deflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source +   stream state was inconsistent. +*/ + +ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm, +                                         gz_headerp head)); +/* +     deflateSetHeader() provides gzip header information for when a gzip +   stream is requested by deflateInit2().  deflateSetHeader() may be called +   after deflateInit2() or deflateReset() and before the first call of +   deflate().  The text, time, os, extra field, name, and comment information +   in the provided gz_header structure are written to the gzip header (xflag is +   ignored -- the extra flags are set according to the compression level).  The +   caller must assure that, if not Z_NULL, name and comment are terminated with +   a zero byte, and that if extra is not Z_NULL, that extra_len bytes are +   available there.  If hcrc is true, a gzip header crc is included.  Note that +   the current versions of the command-line version of gzip (up through version +   1.3.x) do not support header crc's, and will report that it is a "multi-part +   gzip file" and give up. + +     If deflateSetHeader is not used, the default gzip header has text false, +   the time set to zero, and os set to 255, with no extra, name, or comment +   fields.  The gzip header is returned to the default state by deflateReset(). + +     deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source +   stream state was inconsistent. +*/ + +/* +ZEXTERN int ZEXPORT inflateInit2 OF((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 zero to request that inflate use the window size in +   the zlib header of the compressed stream. + +     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_VERSION_ERROR if the zlib library version is incompatible with the +   version assumed by the caller, or Z_STREAM_ERROR if the parameters are +   invalid, such as a null pointer to the structure.  msg is set to null if +   there is no error message.  inflateInit2 does not perform any decompression +   apart from possibly reading the zlib header if present: actual decompression +   will be done by inflate().  (So next_in and avail_in may be modified, but +   next_out and avail_out are unused and unchanged.) The current implementation +   of inflateInit2() does not process any header information -- that is +   deferred until inflate() is called. +*/ + +ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm, +                                             const Bytef *dictionary, +                                             uInt  dictLength)); +/* +     Initializes the decompression dictionary from the given uncompressed byte +   sequence.  This function must be called immediately after a call of inflate, +   if that call returned Z_NEED_DICT.  The dictionary chosen by the compressor +   can be determined from the adler32 value returned by that call of inflate. +   The compressor and decompressor must use exactly the same dictionary (see +   deflateSetDictionary).  For raw inflate, this function can be called +   immediately after inflateInit2() or inflateReset() and before any call of +   inflate() to set the dictionary.  The application must insure that the +   dictionary that was used for compression is provided. + +     inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a +   parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is +   inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the +   expected one (incorrect adler32 value).  inflateSetDictionary does not +   perform any decompression: this will be done by subsequent calls of +   inflate(). +*/ + +ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm)); +/* +     Skips invalid compressed data until a full flush point (see above the +   description of deflate with Z_FULL_FLUSH) can be found, or until all +   available input is skipped.  No output is provided. + +     inflateSync returns Z_OK if a full flush point has been found, Z_BUF_ERROR +   if no more input was provided, Z_DATA_ERROR if no flush point has been +   found, or Z_STREAM_ERROR if the stream structure was inconsistent.  In the +   success case, the application may save the current current value of total_in +   which indicates where valid compressed data was found.  In the error case, +   the application may repeatedly call inflateSync, providing more input each +   time, until success or end of the input data. +*/ + +ZEXTERN int ZEXPORT inflateCopy 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 randomly accessing a large stream.  The +   first pass through the stream can periodically record the inflate state, +   allowing restarting inflate at those points when randomly accessing the +   stream. + +     inflateCopy 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 Z_NULL).  msg is left unchanged in both source and +   destination. +*/ + +ZEXTERN int ZEXPORT inflateReset OF((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 Z_NULL). +*/ + +ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm, +                                      int windowBits)); +/* +     This function is the same as inflateReset, but it also permits changing +   the wrap and window size requests.  The windowBits parameter is interpreted +   the same as it is for inflateInit2. + +     inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source +   stream state was inconsistent (such as zalloc or state being Z_NULL), or if +   the windowBits parameter is invalid. +*/ + +ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm, +                                     int bits, +                                     int value)); +/* +     This function inserts bits in the inflate input stream.  The intent is +   that this function is used to start inflating at a bit position in the +   middle of a byte.  The provided bits will be used before any bytes are used +   from next_in.  This function should only be used with raw inflate, and +   should be used before the first inflate() call after inflateInit2() or +   inflateReset().  bits must be less than or equal to 16, and that many of the +   least significant bits of value will be inserted in the input. + +     If bits is negative, then the input stream bit buffer is emptied.  Then +   inflatePrime() can be called again to put bits in the buffer.  This is used +   to clear out bits leftover after feeding inflate a block description prior +   to feeding inflate codes. + +     inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source +   stream state was inconsistent. +*/ + +ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm)); +/* +     This function returns two values, one in the lower 16 bits of the return +   value, and the other in the remaining upper bits, obtained by shifting the +   return value down 16 bits.  If the upper value is -1 and the lower value is +   zero, then inflate() is currently decoding information outside of a block. +   If the upper value is -1 and the lower value is non-zero, then inflate is in +   the middle of a stored block, with the lower value equaling the number of +   bytes from the input remaining to copy.  If the upper value is not -1, then +   it is the number of bits back from the current bit position in the input of +   the code (literal or length/distance pair) currently being processed.  In +   that case the lower value is the number of bytes already emitted for that +   code. + +     A code is being processed if inflate is waiting for more input to complete +   decoding of the code, or if it has completed decoding but is waiting for +   more output space to write the literal or match data. + +     inflateMark() is used to mark locations in the input data for random +   access, which may be at bit positions, and to note those cases where the +   output of a code may span boundaries of random access blocks.  The current +   location in the input stream can be determined from avail_in and data_type +   as noted in the description for the Z_BLOCK flush parameter for inflate. + +     inflateMark returns the value noted above or -1 << 16 if the provided +   source stream state was inconsistent. +*/ + +ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm, +                                         gz_headerp head)); +/* +     inflateGetHeader() requests that gzip header information be stored in the +   provided gz_header structure.  inflateGetHeader() may be called after +   inflateInit2() or inflateReset(), and before the first call of inflate(). +   As inflate() processes the gzip stream, head->done is zero until the header +   is completed, at which time head->done is set to one.  If a zlib stream is +   being decoded, then head->done is set to -1 to indicate that there will be +   no gzip header information forthcoming.  Note that Z_BLOCK or Z_TREES can be +   used to force inflate() to return immediately after header processing is +   complete and before any actual data is decompressed. + +     The text, time, xflags, and os fields are filled in with the gzip header +   contents.  hcrc is set to true if there is a header CRC.  (The header CRC +   was valid if done is set to one.) If extra is not Z_NULL, then extra_max +   contains the maximum number of bytes to write to extra.  Once done is true, +   extra_len contains the actual extra field length, and extra contains the +   extra field, or that field truncated if extra_max is less than extra_len. +   If name is not Z_NULL, then up to name_max characters are written there, +   terminated with a zero unless the length is greater than name_max.  If +   comment is not Z_NULL, then up to comm_max characters are written there, +   terminated with a zero unless the length is greater than comm_max.  When any +   of extra, name, or comment are not Z_NULL and the respective field is not +   present in the header, then that field is set to Z_NULL to signal its +   absence.  This allows the use of deflateSetHeader() with the returned +   structure to duplicate the header.  However if those fields are set to +   allocated memory, then the application will need to save those pointers +   elsewhere so that they can be eventually freed. + +     If inflateGetHeader is not used, then the header information is simply +   discarded.  The header is always checked for validity, including the header +   CRC if present.  inflateReset() will reset the process to discard the header +   information.  The application would need to call inflateGetHeader() again to +   retrieve the header from the next gzip stream. + +     inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source +   stream state was inconsistent. +*/ + +/* +ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits, +                                        unsigned char FAR *window)); + +     Initialize the internal stream state for decompression using inflateBack() +   calls.  The fields zalloc, zfree and opaque in strm must be initialized +   before the call.  If zalloc and zfree are Z_NULL, then the default library- +   derived memory allocation routines are used.  windowBits is the base two +   logarithm of the window size, in the range 8..15.  window is a caller +   supplied buffer of that size.  Except for special applications where it is +   assured that deflate was used with small window sizes, windowBits must be 15 +   and a 32K byte window must be supplied to be able to decompress general +   deflate streams. + +     See inflateBack() for the usage of these routines. + +     inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of +   the paramaters are invalid, Z_MEM_ERROR if the internal state could not be +   allocated, or Z_VERSION_ERROR if the version of the library does not match +   the version of the header file. +*/ + +typedef unsigned (*in_func) OF((void FAR *, unsigned char FAR * FAR *)); +typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned)); + +ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm, +                                    in_func in, void FAR *in_desc, +                                    out_func out, void FAR *out_desc)); +/* +     inflateBack() does a raw inflate with a single call using a call-back +   interface for input and output.  This is more efficient than inflate() for +   file i/o applications in that it avoids copying between the output and the +   sliding window by simply making the window itself the output buffer.  This +   function trusts the application to not change the output buffer passed by +   the output function, at least until inflateBack() returns. + +     inflateBackInit() must be called first to allocate the internal state +   and to initialize the state with the user-provided window buffer. +   inflateBack() may then be used multiple times to inflate a complete, raw +   deflate stream with each call.  inflateBackEnd() is then called to free the +   allocated state. + +     A raw deflate stream is one with no zlib or gzip header or trailer. +   This routine would normally be used in a utility that reads zip or gzip +   files and writes out uncompressed files.  The utility would decode the +   header and process the trailer on its own, hence this routine expects only +   the raw deflate stream to decompress.  This is different from the normal +   behavior of inflate(), which expects either a zlib or gzip header and +   trailer around the deflate stream. + +     inflateBack() uses two subroutines supplied by the caller that are then +   called by inflateBack() for input and output.  inflateBack() calls those +   routines until it reads a complete deflate stream and writes out all of the +   uncompressed data, or until it encounters an error.  The function's +   parameters and return types are defined above in the in_func and out_func +   typedefs.  inflateBack() will call in(in_desc, &buf) which should return the +   number of bytes of provided input, and a pointer to that input in buf.  If +   there is no input available, in() must return zero--buf is ignored in that +   case--and inflateBack() will return a buffer error.  inflateBack() will call +   out(out_desc, buf, len) to write the uncompressed data buf[0..len-1].  out() +   should return zero on success, or non-zero on failure.  If out() returns +   non-zero, inflateBack() will return with an error.  Neither in() nor out() +   are permitted to change the contents of the window provided to +   inflateBackInit(), which is also the buffer that out() uses to write from. +   The length written by out() will be at most the window size.  Any non-zero +   amount of input may be provided by in(). + +     For convenience, inflateBack() can be provided input on the first call by +   setting strm->next_in and strm->avail_in.  If that input is exhausted, then +   in() will be called.  Therefore strm->next_in must be initialized before +   calling inflateBack().  If strm->next_in is Z_NULL, then in() will be called +   immediately for input.  If strm->next_in is not Z_NULL, then strm->avail_in +   must also be initialized, and then if strm->avail_in is not zero, input will +   initially be taken from strm->next_in[0 ..  strm->avail_in - 1]. + +     The in_desc and out_desc parameters of inflateBack() is passed as the +   first parameter of in() and out() respectively when they are called.  These +   descriptors can be optionally used to pass any information that the caller- +   supplied in() and out() functions need to do their job. + +     On return, inflateBack() will set strm->next_in and strm->avail_in to +   pass back any unused input that was provided by the last in() call.  The +   return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR +   if in() or out() returned an error, Z_DATA_ERROR if there was a format error +   in the deflate stream (in which case strm->msg is set to indicate the nature +   of the error), or Z_STREAM_ERROR if the stream was not properly initialized. +   In the case of Z_BUF_ERROR, an input or output error can be distinguished +   using strm->next_in which will be Z_NULL only if in() returned an error.  If +   strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning +   non-zero.  (in() will always be called before out(), so strm->next_in is +   assured to be defined if out() returns non-zero.) Note that inflateBack() +   cannot return Z_OK. +*/ + +ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm)); +/* +     All memory allocated by inflateBackInit() is freed. + +     inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream +   state was inconsistent. +*/ + +ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void)); +/* Return flags indicating compile-time options. + +    Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other: +     1.0: size of uInt +     3.2: size of uLong +     5.4: size of voidpf (pointer) +     7.6: size of z_off_t + +    Compiler, assembler, and debug options: +     8: DEBUG +     9: ASMV or ASMINF -- use ASM code +     10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention +     11: 0 (reserved) + +    One-time table building (smaller code, but not thread-safe if true): +     12: BUILDFIXED -- build static block decoding tables when needed +     13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed +     14,15: 0 (reserved) + +    Library content (indicates missing functionality): +     16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking +                          deflate code when not needed) +     17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect +                    and decode gzip streams (to avoid linking crc code) +     18-19: 0 (reserved) + +    Operation variations (changes in library functionality): +     20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate +     21: FASTEST -- deflate algorithm with only one, lowest compression level +     22,23: 0 (reserved) + +    The sprintf variant used by gzprintf (zero is best): +     24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format +     25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure! +     26: 0 = returns value, 1 = void -- 1 means inferred string length returned + +    Remainder: +     27-31: 0 (reserved) + */ + + +                        /* utility functions */ + +/* +     The following utility functions are implemented on top of the basic +   stream-oriented functions.  To simplify the interface, some default options +   are assumed (compression level and memory usage, standard memory allocation +   functions).  The source code of these utility functions can be modified if +   you need special options. +*/ + +ZEXTERN int ZEXPORT compress OF((Bytef *dest,   uLongf *destLen, +                                 const Bytef *source, uLong sourceLen)); +/* +     Compresses the source buffer into the destination buffer.  sourceLen is +   the byte length of the source buffer.  Upon entry, destLen is the total size +   of the destination buffer, which must be at least the value returned by +   compressBound(sourceLen).  Upon exit, destLen is the actual size of the +   compressed buffer. + +     compress returns Z_OK if success, Z_MEM_ERROR if there was not +   enough memory, Z_BUF_ERROR if there was not enough room in the output +   buffer. +*/ + +ZEXTERN int ZEXPORT compress2 OF((Bytef *dest,   uLongf *destLen, +                                  const Bytef *source, uLong sourceLen, +                                  int level)); +/* +     Compresses the source buffer into the destination buffer.  The level +   parameter has the same meaning as in deflateInit.  sourceLen is the byte +   length of the source buffer.  Upon entry, destLen is the total size of the +   destination buffer, which must be at least the value returned by +   compressBound(sourceLen).  Upon exit, destLen is the actual size of the +   compressed buffer. + +     compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough +   memory, Z_BUF_ERROR if there was not enough room in the output buffer, +   Z_STREAM_ERROR if the level parameter is invalid. +*/ + +ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen)); +/* +     compressBound() returns an upper bound on the compressed size after +   compress() or compress2() on sourceLen bytes.  It would be used before a +   compress() or compress2() call to allocate the destination buffer. +*/ + +ZEXTERN int ZEXPORT uncompress OF((Bytef *dest,   uLongf *destLen, +                                   const Bytef *source, uLong sourceLen)); +/* +     Decompresses the source buffer into the destination buffer.  sourceLen is +   the byte length of the source buffer.  Upon entry, destLen is the total size +   of the destination buffer, which must be large enough to hold the entire +   uncompressed data.  (The size of the uncompressed data must have been saved +   previously by the compressor and transmitted to the decompressor by some +   mechanism outside the scope of this compression library.) Upon exit, destLen +   is the actual size of the uncompressed buffer. + +     uncompress returns Z_OK if success, Z_MEM_ERROR if there was not +   enough memory, Z_BUF_ERROR if there was not enough room in the output +   buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete. +*/ + + +                        /* gzip file access functions */ + +/* +     This library supports reading and writing files in gzip (.gz) format with +   an interface similar to that of stdio, using the functions that start with +   "gz".  The gzip format is different from the zlib format.  gzip is a gzip +   wrapper, documented in RFC 1952, wrapped around a deflate stream. +*/ + +typedef voidp gzFile;       /* opaque gzip file descriptor */ + +/* +ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode)); + +     Opens a gzip (.gz) file for reading or writing.  The mode parameter is as +   in fopen ("rb" or "wb") but can also include a compression level ("wb9") or +   a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only +   compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F' +   for fixed code compression as in "wb9F".  (See the description of +   deflateInit2 for more information about the strategy parameter.) Also "a" +   can be used instead of "w" to request that the gzip stream that will be +   written be appended to the file.  "+" will result in an error, since reading +   and writing to the same gzip file is not supported. + +     gzopen can be used to read a file which is not in gzip format; in this +   case gzread will directly read from the file without decompression. + +     gzopen returns NULL if the file could not be opened, if there was +   insufficient memory to allocate the gzFile state, or if an invalid mode was +   specified (an 'r', 'w', or 'a' was not provided, or '+' was provided). +   errno can be checked to determine if the reason gzopen failed was that the +   file could not be opened. +*/ + +ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode)); +/* +     gzdopen associates a gzFile with the file descriptor fd.  File descriptors +   are obtained from calls like open, dup, creat, pipe or fileno (if the file +   has been previously opened with fopen).  The mode parameter is as in gzopen. + +     The next call of gzclose on the returned gzFile will also close the file +   descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor +   fd.  If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd, +   mode);.  The duplicated descriptor should be saved to avoid a leak, since +   gzdopen does not close fd if it fails. + +     gzdopen returns NULL if there was insufficient memory to allocate the +   gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not +   provided, or '+' was provided), or if fd is -1.  The file descriptor is not +   used until the next gz* read, write, seek, or close operation, so gzdopen +   will not detect if fd is invalid (unless fd is -1). +*/ + +ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size)); +/* +     Set the internal buffer size used by this library's functions.  The +   default buffer size is 8192 bytes.  This function must be called after +   gzopen() or gzdopen(), and before any other calls that read or write the +   file.  The buffer memory allocation is always deferred to the first read or +   write.  Two buffers are allocated, either both of the specified size when +   writing, or one of the specified size and the other twice that size when +   reading.  A larger buffer size of, for example, 64K or 128K bytes will +   noticeably increase the speed of decompression (reading). + +     The new buffer size also affects the maximum length for gzprintf(). + +     gzbuffer() returns 0 on success, or -1 on failure, such as being called +   too late. +*/ + +ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy)); +/* +     Dynamically update the compression level or strategy.  See the description +   of deflateInit2 for the meaning of these parameters. + +     gzsetparams returns Z_OK if success, or Z_STREAM_ERROR if the file was not +   opened for writing. +*/ + +ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len)); +/* +     Reads the given number of uncompressed bytes from the compressed file.  If +   the input file was not in gzip format, gzread copies the given number of +   bytes into the buffer. + +     After reaching the end of a gzip stream in the input, gzread will continue +   to read, looking for another gzip stream, or failing that, reading the rest +   of the input file directly without decompression.  The entire input file +   will be read if gzread is called until it returns less than the requested +   len. + +     gzread returns the number of uncompressed bytes actually read, less than +   len for end of file, or -1 for error. +*/ + +ZEXTERN int ZEXPORT gzwrite OF((gzFile file, +                                voidpc buf, unsigned len)); +/* +     Writes the given number of uncompressed bytes into the compressed file. +   gzwrite returns the number of uncompressed bytes written or 0 in case of +   error. +*/ + +ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...)); +/* +     Converts, formats, and writes the arguments to the compressed file under +   control of the format string, as in fprintf.  gzprintf returns the number of +   uncompressed bytes actually written, or 0 in case of error.  The number of +   uncompressed bytes written is limited to 8191, or one less than the buffer +   size given to gzbuffer().  The caller should assure that this limit is not +   exceeded.  If it is exceeded, then gzprintf() will return an error (0) with +   nothing written.  In this case, there may also be a buffer overflow with +   unpredictable consequences, which is possible only if zlib was compiled with +   the insecure functions sprintf() or vsprintf() because the secure snprintf() +   or vsnprintf() functions were not available.  This can be determined using +   zlibCompileFlags(). +*/ + +ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s)); +/* +     Writes the given null-terminated string to the compressed file, excluding +   the terminating null character. + +     gzputs returns the number of characters written, or -1 in case of error. +*/ + +ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len)); +/* +     Reads bytes from the compressed file until len-1 characters are read, or a +   newline character is read and transferred to buf, or an end-of-file +   condition is encountered.  If any characters are read or if len == 1, the +   string is terminated with a null character.  If no characters are read due +   to an end-of-file or len < 1, then the buffer is left untouched. + +     gzgets returns buf which is a null-terminated string, or it returns NULL +   for end-of-file or in case of error.  If there was an error, the contents at +   buf are indeterminate. +*/ + +ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c)); +/* +     Writes c, converted to an unsigned char, into the compressed file.  gzputc +   returns the value that was written, or -1 in case of error. +*/ + +ZEXTERN int ZEXPORT gzgetc OF((gzFile file)); +/* +     Reads one byte from the compressed file.  gzgetc returns this byte or -1 +   in case of end of file or error. +*/ + +ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file)); +/* +     Push one character back onto the stream to be read as the first character +   on the next read.  At least one character of push-back is allowed. +   gzungetc() returns the character pushed, or -1 on failure.  gzungetc() will +   fail if c is -1, and may fail if a character has been pushed but not read +   yet.  If gzungetc is used immediately after gzopen or gzdopen, at least the +   output buffer size of pushed characters is allowed.  (See gzbuffer above.) +   The pushed character will be discarded if the stream is repositioned with +   gzseek() or gzrewind(). +*/ + +ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush)); +/* +     Flushes all pending output into the compressed file.  The parameter flush +   is as in the deflate() function.  The return value is the zlib error number +   (see function gzerror below).  gzflush is only permitted when writing. + +     If the flush parameter is Z_FINISH, the remaining data is written and the +   gzip stream is completed in the output.  If gzwrite() is called again, a new +   gzip stream will be started in the output.  gzread() is able to read such +   concatented gzip streams. + +     gzflush should be called only when strictly necessary because it will +   degrade compression if called too often. +*/ + +/* +ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file, +                                   z_off_t offset, int whence)); + +     Sets the starting position for the next gzread or gzwrite on the given +   compressed file.  The offset represents a number of bytes in the +   uncompressed data stream.  The whence parameter is defined as in lseek(2); +   the value SEEK_END is not supported. + +     If the file is opened for reading, this function is emulated but can be +   extremely slow.  If the file is opened for writing, only forward seeks are +   supported; gzseek then compresses a sequence of zeroes up to the new +   starting position. + +     gzseek returns the resulting offset location as measured in bytes from +   the beginning of the uncompressed stream, or -1 in case of error, in +   particular if the file is opened for writing and the new starting position +   would be before the current position. +*/ + +ZEXTERN int ZEXPORT    gzrewind OF((gzFile file)); +/* +     Rewinds the given file. This function is supported only for reading. + +     gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET) +*/ + +/* +ZEXTERN z_off_t ZEXPORT    gztell OF((gzFile file)); + +     Returns the starting position for the next gzread or gzwrite on the given +   compressed file.  This position represents a number of bytes in the +   uncompressed data stream, and is zero when starting, even if appending or +   reading a gzip stream from the middle of a file using gzdopen(). + +     gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR) +*/ + +/* +ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file)); + +     Returns the current offset in the file being read or written.  This offset +   includes the count of bytes that precede the gzip stream, for example when +   appending or when using gzdopen() for reading.  When reading, the offset +   does not include as yet unused buffered input.  This information can be used +   for a progress indicator.  On error, gzoffset() returns -1. +*/ + +ZEXTERN int ZEXPORT gzeof OF((gzFile file)); +/* +     Returns true (1) if the end-of-file indicator has been set while reading, +   false (0) otherwise.  Note that the end-of-file indicator is set only if the +   read tried to go past the end of the input, but came up short.  Therefore, +   just like feof(), gzeof() may return false even if there is no more data to +   read, in the event that the last read request was for the exact number of +   bytes remaining in the input file.  This will happen if the input file size +   is an exact multiple of the buffer size. + +     If gzeof() returns true, then the read functions will return no more data, +   unless the end-of-file indicator is reset by gzclearerr() and the input file +   has grown since the previous end of file was detected. +*/ + +ZEXTERN int ZEXPORT gzdirect OF((gzFile file)); +/* +     Returns true (1) if file is being copied directly while reading, or false +   (0) if file is a gzip stream being decompressed.  This state can change from +   false to true while reading the input file if the end of a gzip stream is +   reached, but is followed by data that is not another gzip stream. + +     If the input file is empty, gzdirect() will return true, since the input +   does not contain a gzip stream. + +     If gzdirect() is used immediately after gzopen() or gzdopen() it will +   cause buffers to be allocated to allow reading the file to determine if it +   is a gzip file.  Therefore if gzbuffer() is used, it should be called before +   gzdirect(). +*/ + +ZEXTERN int ZEXPORT    gzclose OF((gzFile file)); +/* +     Flushes all pending output if necessary, closes the compressed file and +   deallocates the (de)compression state.  Note that once file is closed, you +   cannot call gzerror with file, since its structures have been deallocated. +   gzclose must not be called more than once on the same file, just as free +   must not be called more than once on the same allocation. + +     gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a +   file operation error, or Z_OK on success. +*/ + +ZEXTERN int ZEXPORT gzclose_r OF((gzFile file)); +ZEXTERN int ZEXPORT gzclose_w OF((gzFile file)); +/* +     Same as gzclose(), but gzclose_r() is only for use when reading, and +   gzclose_w() is only for use when writing or appending.  The advantage to +   using these instead of gzclose() is that they avoid linking in zlib +   compression or decompression code that is not used when only reading or only +   writing respectively.  If gzclose() is used, then both compression and +   decompression code will be included the application when linking to a static +   zlib library. +*/ + +ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum)); +/* +     Returns the error message for the last error which occurred on the given +   compressed file.  errnum is set to zlib error number.  If an error occurred +   in the file system and not in the compression library, errnum is set to +   Z_ERRNO and the application may consult errno to get the exact error code. + +     The application must not modify the returned string.  Future calls to +   this function may invalidate the previously returned string.  If file is +   closed, then the string previously returned by gzerror will no longer be +   available. + +     gzerror() should be used to distinguish errors from end-of-file for those +   functions above that do not distinguish those cases in their return values. +*/ + +ZEXTERN void ZEXPORT gzclearerr OF((gzFile file)); +/* +     Clears the error and end-of-file flags for file.  This is analogous to the +   clearerr() function in stdio.  This is useful for continuing to read a gzip +   file that is being written concurrently. +*/ + + +                        /* checksum functions */ + +/* +     These functions are not related to compression but are exported +   anyway because they might be useful in applications using the compression +   library. +*/ + +ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len)); +/* +     Update a running Adler-32 checksum with the bytes buf[0..len-1] and +   return the updated checksum.  If buf is Z_NULL, this function returns the +   required initial value for the checksum. + +     An Adler-32 checksum is almost as reliable as a CRC32 but can be computed +   much faster. + +   Usage example: + +     uLong adler = adler32(0L, Z_NULL, 0); + +     while (read_buffer(buffer, length) != EOF) { +       adler = adler32(adler, buffer, length); +     } +     if (adler != original_adler) error(); +*/ + +/* +ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2, +                                          z_off_t len2)); + +     Combine two Adler-32 checksums into one.  For two sequences of bytes, seq1 +   and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for +   each, adler1 and adler2.  adler32_combine() returns the Adler-32 checksum of +   seq1 and seq2 concatenated, requiring only adler1, adler2, and len2. +*/ + +ZEXTERN uLong ZEXPORT crc32   OF((uLong crc, const Bytef *buf, uInt len)); +/* +     Update a running CRC-32 with the bytes buf[0..len-1] and return the +   updated CRC-32.  If buf is Z_NULL, this function returns the required +   initial value for the for the crc.  Pre- and post-conditioning (one's +   complement) is performed within this function so it shouldn't be done by the +   application. + +   Usage example: + +     uLong crc = crc32(0L, Z_NULL, 0); + +     while (read_buffer(buffer, length) != EOF) { +       crc = crc32(crc, buffer, length); +     } +     if (crc != original_crc) error(); +*/ + +/* +ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2)); + +     Combine two CRC-32 check values into one.  For two sequences of bytes, +   seq1 and seq2 with lengths len1 and len2, CRC-32 check values were +   calculated for each, crc1 and crc2.  crc32_combine() returns the CRC-32 +   check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and +   len2. +*/ + + +                        /* various hacks, don't look :) */ + +/* deflateInit and inflateInit are macros to allow checking the zlib version + * and the compiler's view of z_stream: + */ +ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level, +                                     const char *version, int stream_size)); +ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm, +                                     const char *version, int stream_size)); +ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int  level, int  method, +                                      int windowBits, int memLevel, +                                      int strategy, const char *version, +                                      int stream_size)); +ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int  windowBits, +                                      const char *version, int stream_size)); +ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits, +                                         unsigned char FAR *window, +                                         const char *version, +                                         int stream_size)); +#define deflateInit(strm, level) \ +        deflateInit_((strm), (level),       ZLIB_VERSION, sizeof(z_stream)) +#define inflateInit(strm) \ +        inflateInit_((strm),                ZLIB_VERSION, sizeof(z_stream)) +#define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \ +        deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\ +                      (strategy),           ZLIB_VERSION, sizeof(z_stream)) +#define inflateInit2(strm, windowBits) \ +        inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream)) +#define inflateBackInit(strm, windowBits, window) \ +        inflateBackInit_((strm), (windowBits), (window), \ +                                            ZLIB_VERSION, sizeof(z_stream)) + +/* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or + * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if + * both are true, the application gets the *64 functions, and the regular + * functions are changed to 64 bits) -- in case these are set on systems + * without large file support, _LFS64_LARGEFILE must also be true + */ +#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0 +   ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *)); +   ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int)); +   ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile)); +   ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile)); +   ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t)); +   ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t)); +#endif + +#if !defined(ZLIB_INTERNAL) && _FILE_OFFSET_BITS-0 == 64 && _LFS64_LARGEFILE-0 +#  define gzopen gzopen64 +#  define gzseek gzseek64 +#  define gztell gztell64 +#  define gzoffset gzoffset64 +#  define adler32_combine adler32_combine64 +#  define crc32_combine crc32_combine64 +#  ifdef _LARGEFILE64_SOURCE +     ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *)); +     ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int)); +     ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile)); +     ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile)); +     ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t)); +     ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t)); +#  endif +#else +   ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *)); +   ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int)); +   ZEXTERN z_off_t ZEXPORT gztell OF((gzFile)); +   ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile)); +   ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t)); +   ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t)); +#endif + +/* hack for buggy compilers */ +#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL) +    struct internal_state {int dummy;}; +#endif + +/* undocumented functions */ +ZEXTERN const char   * ZEXPORT zError           OF((int)); +ZEXTERN int            ZEXPORT inflateSyncPoint OF((z_streamp)); +ZEXTERN const uLongf * ZEXPORT get_crc_table    OF((void)); +ZEXTERN int            ZEXPORT inflateUndermine OF((z_streamp, int)); + +#ifdef __cplusplus +} +#endif + +#endif /* ZLIB_H */ | 
