sdch/open_vcdiff/depot/opensource/open-vcdiff/src/zlib.h - Issue 5203: Transition to pulling open-vcdiff from repository, instead of using snapshot...

Unified Diff: sdch/open_vcdiff/depot/opensource/open-vcdiff/src/zlib.h

Issue 5203: Transition to pulling open-vcdiff from repository, instead of using snapshot... (Closed) Base URL: svn://chrome-svn/chrome/trunk/src/

Patch Set: Created 12 years, 3 months ago

Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.

Jump to:

View side-by-side diff with in-line comments

Download patch

« no previous file with comments | « sdch/open_vcdiff/depot/opensource/open-vcdiff/src/zconf.h ('k') | sdch/open_vcdiff/depot/opensource/open-vcdiff/vsprojects/addrcache_test/addrcache_test.vcproj » ('j') | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Hide Comments ('s')

Index: sdch/open_vcdiff/depot/opensource/open-vcdiff/src/zlib.h

===================================================================

--- sdch/open_vcdiff/depot/opensource/open-vcdiff/src/zlib.h (revision 2678)

+++ sdch/open_vcdiff/depot/opensource/open-vcdiff/src/zlib.h (working copy)

@@ -1,1373 +0,0 @@

-/* zlib.h -- interface of the 'zlib' general purpose compression library

- version 1.2.3, July 18th, 2005

- 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 "1.2.3"

-#define ZLIB_VERNUM 0x1230

-/*

- 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 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 /* will be removed, use Z_SYNC_FLUSH instead */

-#define Z_SYNC_FLUSH 2

-#define Z_FULL_FLUSH 3

-#define Z_FINISH 4

-#define Z_BLOCK 5

-/* 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,

- 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 accumualte 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.

- 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 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. msg is set to null if there is no error

- message. inflateInit does not perform any decompression apart from reading

- the zlib header if present: this will be done by inflate(). (So next_in and

- avail_in may be modified, but next_out and avail_out are unchanged.)

-*/

-ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush));

-/*

- inflate decompresses as much data as possible, and stops when the input

- buffer becomes empty or the output buffer becomes full. It may introduce

- some output latency (reading input without producing any output) except when

- forced to flush.

- The detailed semantics are as follows. inflate performs one or both of the

- following actions:

- - Decompress more input starting at next_in and update next_in and avail_in

- accordingly. If not all input can be processed (because there is not

- enough room in the output buffer), next_in is updated and processing

- will resume at this point for the next call of inflate().

- - Provide more output starting at next_out and update next_out and avail_out

- accordingly. inflate() provides as much output as possible, until there

- is no more input data or no more space in the output buffer (see below

- about the flush parameter).

- Before the call of inflate(), the application should ensure that at least

- one of the actions is possible, by providing more input and/or consuming

- more output, and updating the next_* and avail_* values accordingly.

- The application can consume the uncompressed output when it wants, for

- example when the output buffer is full (avail_out == 0), or after each

- call of inflate(). If inflate returns Z_OK and with zero avail_out, it

- must be called again after making room in the output buffer because there

- might be more output pending.

- The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,

- Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much

- output as possible to the output buffer. Z_BLOCK requests that inflate() stop

- if and when it 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.

-*/

-ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));

-/*

- All dynamically allocated data structures for this stream are freed.

- This function discards any unprocessed input and does not flush any

- pending output.

- inflateEnd returns Z_OK if success, Z_STREAM_ERROR if the stream state

- was inconsistent. In the error case, msg may be set but then points to a

- static string (which must not be deallocated).

-*/

- /* Advanced functions */

-/*

- The following functions are needed only in some special applications.

-*/

-/*

-ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,

- int level,

- int method,

- int windowBits,

- int memLevel,

- int strategy));

- This is another version of deflateInit with more compression options. The

- fields next_in, zalloc, zfree and opaque must be initialized before by

- the caller.

- The method parameter is the compression method. It must be Z_DEFLATED in

- this version of the library.

- The windowBits parameter is the base two logarithm of the window size

- (the size of the history buffer). It should be in the range 8..15 for this

- version of the library. Larger values of this parameter result in better

- compression at the expense of memory usage. The default value is 15 if

- deflateInit is used instead.

- windowBits can also be -8..-15 for raw deflate. In this case, -windowBits

- determines the window size. deflate() will then generate raw deflate data

- with no zlib header or trailer, and will not compute an adler32 check value.

- windowBits can also be greater than 15 for optional gzip encoding. Add

- 16 to windowBits to write a simple gzip header and trailer around the

- compressed data instead of a zlib wrapper. The gzip header will have no

- file name, no extra data, no comment, no modification time (set to zero),

- no header crc, and the operating system will be set to 255 (unknown). If a

- gzip stream is being written, strm->adler is a crc32 instead of an adler32.

- The memLevel parameter specifies how much memory should be allocated

- for the internal compression state. memLevel=1 uses minimum memory but

- is slow and reduces compression ratio; memLevel=9 uses maximum memory

- for optimal speed. The default value is 8. See zconf.h for total memory

- usage as a function of windowBits and memLevel.

- The strategy parameter is used to tune the compression algorithm. Use the

- value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a

- filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no

- string match), or Z_RLE to limit match distances to one (run-length

- encoding). Filtered data consists mostly of small values with a somewhat

- random distribution. In this case, the compression algorithm is tuned to

- compress them better. The effect of Z_FILTERED is to force more Huffman

- coding and less string matching; it is somewhat intermediate between

- Z_DEFAULT and Z_HUFFMAN_ONLY. Z_RLE is designed to be almost as fast as

- Z_HUFFMAN_ONLY, but give better compression for PNG image data. The strategy

- parameter only affects the compression ratio but not the correctness of the

- compressed output even if it is not set appropriately. 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 a parameter is invalid (such as an invalid

- method). msg is set to null if there is no error message. deflateInit2 does

- not perform any compression: this will be done by deflate().

-*/

-ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,

- const Bytef *dictionary,

- uInt dictLength));

-/*

- Initializes the compression dictionary from the given byte sequence

- without producing any compressed output. This function must be called

- immediately after deflateInit, deflateInit2 or deflateReset, before any

- call of deflate. The compressor and decompressor must use exactly the same

- dictionary (see inflateSetDictionary).

- The dictionary should consist of strings (byte sequences) that are likely

- to be encountered later in the data to be compressed, with the most commonly

- used strings preferably put towards the end of the dictionary. Using a

- dictionary is most useful when the data to be compressed is short and can be

- predicted with good accuracy; the data can then be compressed better than

- with the default empty dictionary.

- Depending on the size of the compression data structures selected by

- deflateInit or deflateInit2, a part of the dictionary may in effect be

- discarded, for example if the dictionary is larger than the window size in

- deflate or deflate2. Thus the strings most likely to be useful should be

- put at the end of the dictionary, not at the front. 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 (such as NULL dictionary) or the stream state is

- inconsistent (for example if deflate has already been called for this stream

- or if the compression method is bsort). deflateSetDictionary does not

- perform any compression: this will be done by deflate().

-*/

-ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,

- z_streamp source));

-/*

- Sets the destination stream as a complete copy of the source stream.

- This function can be useful when several compression strategies will be

- tried, for example when there are several ways of pre-processing the input

- data with a filter. The streams that will be discarded should then be freed

- by calling deflateEnd. Note that deflateCopy duplicates the internal

- compression state which can be quite large, so this strategy is slow and

- can consume lots of memory.

- deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not

- enough memory, Z_STREAM_ERROR if the source stream state was inconsistent

- (such as zalloc being NULL). msg is left unchanged in both source and

- destination.

-*/

-ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));

-/*

- This function is equivalent to deflateEnd followed by deflateInit,

- but does not free and reallocate all the internal compression state.

- The stream will keep the same compression level and any other attributes

- that may have been set by deflateInit2.

- deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source

- stream state was inconsistent (such as zalloc or state being NULL).

-*/

-ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,

- int level,

- int strategy));

-/*

- Dynamically update the compression level and compression strategy. The

- interpretation of level and strategy is as in deflateInit2. This can be

- used to switch between compression and straight copy of the input data, or

- to switch to a different kind of input data requiring a different

- strategy. If the compression level is changed, the input available so far

- is compressed with the old level (and may be flushed); the new level will

- take effect only at the next call of deflate().

- Before the call of deflateParams, the stream state must be set as for

- a call of deflate(), since the currently available input may have to

- be compressed and flushed. In particular, strm->avail_out must be non-zero.

- deflateParams returns Z_OK if success, Z_STREAM_ERROR if the source

- stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR

- if strm->avail_out was zero.

-*/

-ZEXTERN 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(). 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 -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.)

-*/

-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 (such as NULL dictionary) 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 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 NULL).

-*/

-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.

- inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the 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 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 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 easily 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.

- This function can be used to compress a whole file at once if the

- input file is mmap'ed.

- 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 compressed buffer.

- This function can be used to decompress a whole file at once if the

- input file is mmap'ed.

- 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.

-*/

-typedef voidp gzFile;

-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", or 'R' for run-length encoding

- as in "wb1R". (See the description of deflateInit2 for more information

- about the strategy parameter.)

- 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 or if there was

- insufficient memory to allocate the (de)compression state; errno

- can be checked to distinguish the two cases (if errno is zero, the

- zlib error is Z_MEM_ERROR). */

-long long gzgetMtime(gzFile file);

-/* Return modify time */

-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 (in 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 gzdopen(dup(fd), mode).

- gzdopen returns NULL if there was insufficient memory to allocate

- the (de)compression state.

-*/

-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.

- gzread returns the number of uncompressed bytes actually read (0 for

- end of file, -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 actually written

- (0 in case of error).

-*/

-ZEXTERN int ZEXPORTVA gzprintf OF((gzFile file, const char *format, ...));

-/*

- Converts, formats, and writes the args to the compressed file under

- control of the format string, as in fprintf. gzprintf returns the number of

- uncompressed bytes actually written (0 in case of error). The number of

- uncompressed bytes written is limited to 4095. The caller should assure that

- this limit is not exceeded. If it is exceeded, then gzprintf() will return

- 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.

-*/

-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. The string is then terminated with a null

- character.

- gzgets returns buf, or Z_NULL in case of error.

-*/

-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 again later.

- Only one character of push-back is allowed. gzungetc() returns the

- character pushed, or -1 on failure. gzungetc() will fail if a

- character has been pushed but not read yet, or if c is -1. 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 returns Z_OK if

- the flush parameter is Z_FINISH and all output could be flushed.

- gzflush should be called only when strictly necessary because it can

- degrade compression.

-*/

-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.

- gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)

-*/

-ZEXTERN int ZEXPORT gzeof OF((gzFile file));

-/*

- Returns 1 when EOF has previously been detected reading the given

- input stream, otherwise zero.

-*/

-ZEXTERN int ZEXPORT gzdirect OF((gzFile file));

-/*

- Returns 1 if file is being read directly without decompression, otherwise

- zero.

-*/

-ZEXTERN int ZEXPORT gzclose OF((gzFile file));

-/*

- Flushes all pending output if necessary, closes the compressed file

- and deallocates all the (de)compression state. The return value is the zlib

- error number (see function gzerror below).

-*/

-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.

-*/

-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 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 void ZEXPORT adler32_range OF((uLong* min, uLong* max));

-/*

- Set *min and *max (both of which must not be null) to the minimum and

- maximum possible checksum values that adler32 can produce.

- This function is not part of original software distribution. It is

- which permits alteration and redistribution of the original software

- provided, among other things, that altered source versions must be

- plainly marked as such and not misrepresented as being the original

- software.

-*/

-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 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))

-#if !defined(ZUTIL_H) && !defined(NO_DUMMY_DECL)

- struct internal_state {int dummy;}; /* hack for buggy compilers */

-#endif

-ZEXTERN const char * ZEXPORT zError OF((int));

-ZEXTERN int ZEXPORT inflateSyncPoint OF((z_streamp z));

-ZEXTERN const uLongf * ZEXPORT get_crc_table OF((void));

-#ifdef __cplusplus

-#endif

-#endif /* ZLIB_H */