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zlib 1.0.1

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Mark Adler
2011-09-09 23:14:39 -07:00
parent 8a2acbffc8
commit 423eb40306
37 changed files with 1812 additions and 679 deletions
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213
zlib.h
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@@ -1,5 +1,5 @@
/* zlib.h -- interface of the 'zlib' general purpose compression library
version 1.0, Jan 14th, 1996.
version 1.0.1, May 20th, 1996.
Copyright (C) 1995-1996 Jean-loup Gailly and Mark Adler
@@ -32,7 +32,7 @@ extern "C" {
#include "zconf.h"
#define ZLIB_VERSION "1.0"
#define ZLIB_VERSION "1.0.1"
/*
The 'zlib' compression library provides in-memory compression and
@@ -51,6 +51,11 @@ extern "C" {
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 library does not install any signal handler. It is recommended to
add at least a handler for SIGSEGV when decompressing; the library checks
the consistency of the input data whenever possible but may go nuts
for some forms of corrupted input.
*/
typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
@@ -74,8 +79,9 @@ typedef struct z_stream_s {
free_func zfree; /* used to free the internal state */
voidpf opaque; /* private data object passed to zalloc and zfree */
Byte data_type; /* best guess about the data type: ascii or binary */
int data_type; /* best guess about the data type: ascii or binary */
uLong adler; /* adler32 value of the uncompressed data */
uLong reserved; /* reserved for future use */
} z_stream;
/*
@@ -118,12 +124,16 @@ typedef struct z_stream_s {
#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)
/* error codes for the compression/decompression functions */
#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
@@ -134,18 +144,19 @@ typedef struct z_stream_s {
#define Z_FILTERED 1
#define Z_HUFFMAN_ONLY 2
#define Z_DEFAULT_STRATEGY 0
/* compression strategy; see deflateInit2() below for details */
#define Z_BINARY 0
#define Z_ASCII 1
#define Z_UNKNOWN 2
/* Used to set the data_type field */
/* Possible values of the data_type field */
#define Z_DEFLATED 8
/* The deflate compression method (the only one supported in this version) */
#define Z_NULL 0 /* for initializing zalloc, zfree, opaque */
extern char *zlib_version;
extern const char *zlib_version;
/* The application can compare zlib_version 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.
@@ -153,8 +164,9 @@ extern char *zlib_version;
/* basic functions */
extern int deflateInit OF((z_stream *strm, int level));
/*
extern int deflateInit OF((z_stream *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
@@ -167,7 +179,9 @@ extern int deflateInit OF((z_stream *strm, int level));
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.
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().
*/
@@ -193,7 +207,9 @@ extern int deflate OF((z_stream *strm, int flush));
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().
(avail_out == 0), or after each call of deflate(). If deflate returns Z_OK
and with zero avail_out, it must be called again after making room in the
output buffer because there might be more output pending.
If the parameter flush is set to Z_PARTIAL_FLUSH, the current compression
block is terminated and flushed to the output buffer so that the
@@ -247,22 +263,26 @@ extern int deflateEnd OF((z_stream *strm));
pending output.
deflateEnd 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).
stream state was inconsistent, Z_DATA_ERROR if the stream was freed
prematurely (some input or output was discarded). In the error case,
msg may be set but then points to a static string (which must not be
deallocated).
*/
extern int inflateInit OF((z_stream *strm));
/*
extern int inflateInit OF((z_stream *strm));
Initializes the internal stream state for decompression. The fields
zalloc, zfree and opaque must be initialized before by the caller. 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. msg is set to null if there is no error message.
inflateInit does not perform any decompression: this will be done by
inflate().
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: this will be
done by inflate().
*/
@@ -276,15 +296,18 @@ extern int inflate OF((z_stream *strm, int flush));
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() always provides as much output as possible
(until there is no more input data or no more space in the output buffer).
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().
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.
If the parameter flush is set to Z_PARTIAL_FLUSH, inflate flushes as much
output as possible to the output buffer. The flushing behavior of inflate is
@@ -306,12 +329,15 @@ extern int inflate OF((z_stream *strm, int flush));
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_DATA_ERROR if the input data was corrupted, 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. In the Z_DATA_ERROR case, the application may then
call inflateSync to look for a good compression block.
produced, Z_NEED_DICT if a preset dictionary is needed at this point (see
inflateSetDictionary below), Z_DATA_ERROR if the input data was corrupted,
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. In the Z_DATA_ERROR case, the
application may then call inflateSync to look for a good compression block.
In the Z_NEED_DICT case, strm->adler is set to the Adler32 value of the
dictionary chosen by the compressor.
*/
@@ -326,19 +352,20 @@ extern int inflateEnd OF((z_stream *strm));
static string (which must not be deallocated).
*/
/* advanced functions */
/* Advanced functions */
/*
The following functions are needed only in some special applications.
*/
/*
extern int deflateInit2 OF((z_stream *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.
@@ -353,20 +380,22 @@ extern int deflateInit2 OF((z_stream *strm,
values of this parameter result in better compression at the expense of
memory usage. The default value is 15 if deflateInit is used instead.
The memLevel parameter specifies how much memory should be allocated
The memLevel parameter specifies how much memory should be allocated
for the internal compression state. memLevel=1 uses minimum memory but
is slow and reduces compression ratio; memLevel=9 uses maximum memory
for optimal speed. The default value is 8. See zconf.h for total memory
usage as a function of windowBits and memLevel.
The strategy parameter is used to tune the compression algorithm. Use
the value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data
produced by a filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman
encoding only (no string match). Filtered data consists mostly of small
values with a somewhat random distribution. In this case, the
compression algorithm is tuned to compress them better. The strategy
parameter only affects the compression ratio but not the correctness of
the compressed output even if it is not set appropriately.
The strategy parameter is used to tune the compression algorithm. Use the
value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
filter (or predictor), or Z_HUFFMAN_ONLY to force Huffman encoding only (no
string match). Filtered data consists mostly of small values with a
somewhat random distribution. In this case, the compression algorithm is
tuned to compress them better. The effect of Z_FILTERED is to force more
Huffman coding and less string matching; it is somewhat intermediate
between Z_DEFAULT and Z_HUFFMAN_ONLY. The strategy parameter only affects
the compression ratio but not the correctness of the compressed output even
if it is not set appropriately.
If next_in is not null, the library will use this buffer to hold also
some history information; the buffer must either hold the entire input
@@ -385,9 +414,38 @@ extern int deflateInit2 OF((z_stream *strm,
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().
deflate().
*/
extern int deflateSetDictionary OF((z_stream *strm,
const Bytef *dictionary,
uInt dictLength));
/*
Initializes the compression dictionary (history buffer) from the given
byte sequence without producing any compressed output. This function must
be called immediately after deflateInit or deflateInit2, 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. In this version of the library,
only the last 32K bytes of the dictionary are used.
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.)
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). deflateSetDictionary does not perform any compression: this will
be done by deflate().
*/
extern int deflateCopy OF((z_stream *dest,
z_stream *source));
/*
@@ -398,14 +456,14 @@ extern int deflateCopy OF((z_stream *dest,
application to provide the correct values of next_out and avail_out for the
next call of deflate.
This function is useful when several compression strategies will be
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
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.
@@ -431,13 +489,19 @@ extern int deflateParams OF((z_stream *strm, int level, int strategy));
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.
stream state was inconsistent or if a parameter was invalid, Z_BUF_ERROR
if strm->avail_out was zero.
*/
/*
extern int inflateInit2 OF((z_stream *strm,
int windowBits));
/*
This is another version of inflateInit with more compression options. The
fields next_out, zalloc, zfree and opaque must be initialized before by
the caller.
@@ -469,6 +533,25 @@ extern int inflateInit2 OF((z_stream *strm,
inflate().
*/
extern int inflateSetDictionary OF((z_stream *strm,
const Bytef *dictionary,
uInt dictLength));
/*
Initializes the decompression dictionary (history buffer) from the given
uncompressed byte sequence. This function must be called immediately after
a call of inflate if this call returned Z_NEED_DICT. The dictionary chosen
by the compressor can be determined from the Adler32 value returned by this
call of inflate. The compressor and decompressor must use exactly the same
dictionary (see deflateSetDictionary).
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().
*/
extern int inflateSync OF((z_stream *strm));
/*
Skips invalid compressed data until the special marker (see deflate()
@@ -506,7 +589,7 @@ extern int inflateReset OF((z_stream *strm));
*/
extern int compress OF((Bytef *dest, uLongf *destLen,
Bytef *source, uLong sourceLen));
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
@@ -521,7 +604,7 @@ extern int compress OF((Bytef *dest, uLongf *destLen,
*/
extern int uncompress OF((Bytef *dest, uLongf *destLen,
Bytef *source, uLong sourceLen));
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
@@ -541,7 +624,7 @@ extern int uncompress OF((Bytef *dest, uLongf *destLen,
typedef voidp gzFile;
extern gzFile gzopen OF((char *path, char *mode));
extern gzFile 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
@@ -553,12 +636,15 @@ extern gzFile gzopen OF((char *path, char *mode));
zlib error is Z_MEM_ERROR).
*/
extern gzFile gzdopen OF((int fd, char *mode));
extern gzFile 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 fopen ("rb" or "wb").
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.
*/
@@ -571,7 +657,7 @@ extern int gzread OF((gzFile file, voidp buf, unsigned len));
gzread returns the number of uncompressed bytes actually read (0 for
end of file, -1 for error). */
extern int gzwrite OF((gzFile file, voidp buf, unsigned len));
extern int gzwrite OF((gzFile file, const voidp buf, unsigned len));
/*
Writes the given number of uncompressed bytes into the compressed file.
gzwrite returns the number of uncompressed bytes actually written
@@ -612,7 +698,7 @@ extern char* gzerror OF((gzFile file, int *errnum));
compression library.
*/
extern uLong adler32 OF((uLong adler, Bytef *buf, uInt len));
extern uLong adler32 OF((uLong adler, const Bytef *buf, uInt len));
/*
Update a running Adler-32 checksum with the bytes buf[0..len-1] and
@@ -629,7 +715,7 @@ extern uLong adler32 OF((uLong adler, Bytef *buf, uInt len));
if (adler != original_adler) error();
*/
extern uLong crc32 OF((uLong crc, Bytef *buf, uInt len));
extern uLong crc32 OF((uLong crc, const Bytef *buf, uInt len));
/*
Update a running crc with the bytes buf[0..len-1] and return the updated
crc. If buf is NULL, this function returns the required initial value
@@ -645,10 +731,37 @@ extern uLong crc32 OF((uLong crc, Bytef *buf, uInt len));
if (crc != original_crc) error();
*/
#ifndef _Z_UTIL_H
/* various hacks, don't look :) */
/* deflateInit and inflateInit are macros to allow checking the zlib version
* and the compiler's view of z_stream:
*/
extern int deflateInit_ OF((z_stream *strm, int level,
const char *version, int stream_size));
extern int inflateInit_ OF((z_stream *strm,
const char *version, int stream_size));
extern int deflateInit2_ OF((z_stream *strm, int level, int method,
int windowBits, int memLevel, int strategy,
const char *version, int stream_size));
extern int inflateInit2_ OF((z_stream *strm, int windowBits,
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))
#if !defined(_Z_UTIL_H) && !defined(NO_DUMMY_DECL)
struct internal_state {int dummy;}; /* hack for buggy compilers */
#endif
uLongf *get_crc_table OF((void)); /* can be used by asm versions of crc32() */
#ifdef __cplusplus
}
#endif