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zlib 1.2.2.1

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This commit is contained in:
Mark Adler
2011-09-09 23:24:24 -07:00
parent 79fbcdc939
commit 9811b53dd9
36 changed files with 1334 additions and 429 deletions
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157
zlib.h
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@@ -1,5 +1,5 @@
/* zlib.h -- interface of the 'zlib' general purpose compression library
version 1.2.2, October 3rd, 2004
version 1.2.2.1, October 31st, 2004
Copyright (C) 1995-2004 Jean-loup Gailly and Mark Adler
@@ -37,8 +37,8 @@
extern "C" {
#endif
#define ZLIB_VERSION "1.2.2"
#define ZLIB_VERNUM 0x1220
#define ZLIB_VERSION "1.2.2.1"
#define ZLIB_VERNUM 0x1221
/*
The 'zlib' compression library provides in-memory compression and
@@ -95,13 +95,36 @@ typedef struct z_stream_s {
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: ascii or binary */
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
@@ -170,7 +193,8 @@ typedef z_stream FAR *z_streamp;
/* compression strategy; see deflateInit2() below for details */
#define Z_BINARY 0
#define Z_ASCII 1
#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()) */
@@ -244,6 +268,10 @@ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
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
@@ -255,7 +283,7 @@ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
Z_SYNC_FLUSH, and the compression state is reset so that decompression can
restart from this point if previous compressed data has been damaged or if
random access is desired. Using Z_FULL_FLUSH too often can seriously degrade
the compression.
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
@@ -280,8 +308,8 @@ ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
deflate() sets strm->adler to the adler32 checksum of all input read
so far (that is, total_in bytes).
deflate() may update data_type if it can make a good guess about
the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered
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.
@@ -616,6 +644,30 @@ ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
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));
@@ -664,11 +716,14 @@ ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
uInt dictLength));
/*
Initializes the decompression dictionary 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).
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
@@ -719,8 +774,48 @@ ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
stream state was inconsistent (such as zalloc or state being NULL).
*/
ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
gz_headerp head));
/*
ZEXTERN int ZEXPORT inflateBackInit OF((z_stream FAR *strm, int windowBits,
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()
@@ -744,7 +839,7 @@ ZEXTERN int ZEXPORT inflateBackInit OF((z_stream FAR *strm, int windowBits,
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_stream FAR *strm,
ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
in_func in, void FAR *in_desc,
out_func out, void FAR *out_desc));
/*
@@ -813,7 +908,7 @@ ZEXTERN int ZEXPORT inflateBack OF((z_stream FAR *strm,
that inflateBack() cannot return Z_OK.
*/
ZEXTERN int ZEXPORT inflateBackEnd OF((z_stream FAR *strm));
ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
/*
All memory allocated by inflateBackInit() is freed.
@@ -1119,7 +1214,6 @@ ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
*/
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
@@ -1135,12 +1229,21 @@ ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
if (adler != original_adler) error();
*/
ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
uLong 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 with the bytes buf[0..len-1] and return the updated
crc. If buf is NULL, this function returns the required initial value
for the crc. Pre- and post-conditioning (one's complement) is performed
within this function so it shouldn't be done by the application.
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);
@@ -1151,6 +1254,16 @@ ZEXTERN uLong ZEXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
if (crc != original_crc) error();
*/
ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, uLong 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 :) */
@@ -1167,7 +1280,7 @@ ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
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_stream FAR *strm, int windowBits,
ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
unsigned char FAR *window,
const char *version,
int stream_size));