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zlib 0.79

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This commit is contained in:
Mark Adler
2011-09-09 22:52:17 -07:00
parent bcf78a2097
commit 913afb9174
23 changed files with 559 additions and 140 deletions
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96
zlib.h
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@@ -1,5 +1,5 @@
/* zlib.h -- interface of the 'zlib' general purpose compression library
version 0.7 April 14th, 1995.
version 0.79 April 28th, 1995.
Copyright (C) 1995 Jean-loup Gailly and Mark Adler
@@ -28,7 +28,7 @@
#include "zconf.h"
#define ZLIB_VERSION "0.7"
#define ZLIB_VERSION "0.79"
/*
The 'zlib' compression library provides in-memory compression and
@@ -88,7 +88,7 @@ typedef struct z_stream_s {
zalloc must return Z_NULL if there is not enough memory for the object.
On 16-bit systems, the functions zalloc and zfree must be able to allocate
exactly 65536 bytes, but will not be require to allocate more than this
exactly 65536 bytes, but will not be required to allocate more than this
if the symbol MAXSEG_64K is defined (see zconf.h).
The fields total_in and total_out can be used for statistics or
@@ -152,10 +152,10 @@ extern int deflateInit __P((z_stream *strm, int level));
to level 6).
deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
enough memory, Z_STREAM_ERROR if the stream state was inconsistent (such
as zalloc being NULL). msg is set to null if there is no error message.
deflateInit does not perform any compression: this will be done by
deflate(). */
enough memory, Z_STREAM_ERROR if level is not a valid compression level.
msg is set to null if there is no error message. deflateInit does not
perform any compression: this will be done by deflate().
*/
extern int deflate __P((z_stream *strm, int flush));
@@ -164,8 +164,8 @@ extern int deflate __P((z_stream *strm, int flush));
- 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 is updated and processing
will resume at this point for the next call of deflate().
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.
@@ -175,20 +175,21 @@ extern int deflate __P((z_stream *strm, int flush));
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.
The application can consume the compressed output when the output
buffer is full (avail_out == 0), or after each call of deflate().
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 the parameter flush is set to Z_PARTIAL_FLUSH, the current compression
block is byte aligned and flushed to the output buffer so that the
decompressor can get all input data available so far; if the compression
method is 8 (deflate without partial flush capability), the current block
is terminated. If flush is set to Z_FULL_FLUSH, the compression block is
terminated, a special marker is output and the compression dictionary is
discarded; this is useful to allow the decompressor to synchronize if one
compressed block has been damaged.
Flushing degrades compression and so should be used only when necessary.
Using Z_FULL_FLUSH too often can seriously degrade the compression.
block is terminated and flushed to the output buffer so that the
decompressor can get all input data available so far. For method 9, a future
variant on method 8, the current block will be flushed but not terminated.
If flush is set to Z_FULL_FLUSH, the compression block is terminated, a
special marker is output and the compression dictionary is discarded; this
is useful to allow the decompressor to synchronize if one compressed block
has been damaged (see inflateSync below). Flushing degrades compression and
so should be used only when necessary. Using Z_FULL_FLUSH too often can
seriously degrade the compression.
If the parameter flush is set to Z_FINISH, all pending input is
processed and all pending output is flushed. The next operation on this
@@ -197,19 +198,18 @@ extern int deflate __P((z_stream *strm, int flush));
or a call of deflateEnd to deallocate the compression state. Z_FINISH can
be used immediately after deflateInit if all the compression is to be
done in a single step. In this case, avail_out must be at least 0.1%
larger than avail_in plus 8 bytes.
larger than avail_in plus 12 bytes.
deflate() may update strm->data_type if it can make a good guess about
deflate() may update data_type if it can make a good guess about
the input data type (Z_ASCII or Z_BINARY). In doubt, the data is considered
binary. This field is only for information purposes and does not affect
the compression algorithm in any manner.
deflate() return Z_OK if some progress has been made (more input processed
deflate() returns Z_OK if some progress has been made (more input processed
or more output produced), 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 or if there was not enough room in the output buffer
when Z_FINISH is used.
*/
when Z_FINISH is used. ??? to be changed (use Z_STEAM_END) */
extern int deflateEnd __P((z_stream *strm));
@@ -232,8 +232,7 @@ extern int inflateInit __P((z_stream *strm));
functions.
inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not
enough memory, Z_STREAM_ERROR if the stream state was inconsistent (such
as zalloc being NULL). msg is set to null if there is no error message.
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().
*/
@@ -255,8 +254,9 @@ extern int inflate __P((z_stream *strm, int flush));
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 the output
buffer is full (avail_out == 0), or after each call of inflate().
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 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
@@ -275,13 +275,13 @@ extern int inflate __P((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, 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.
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.
*/
@@ -318,9 +318,9 @@ extern int deflateInit2 __P((z_stream *strm,
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 (the value 16 will be allowed soon). 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.
version of the library (the value 16 will be allowed for method 9). Larger
values of this parameter result in better compression at the expense of
memory usage. The default value is 15 if deflateInit is used instead.
The memLevel parameter specifies how much memory should be allocated
for the internal compression state. memLevel=1 uses minimum memory but
@@ -338,8 +338,8 @@ extern int deflateInit2 __P((z_stream *strm,
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
data, or have at least (1<<windowBits) bytes and be writable. If next_in is
null, the library will allocate its own history buffer (and leave next_in
data, or have at least 1<<(windowBits+1) bytes and be writable. If next_in
is null, the library will allocate its own history buffer (and leave next_in
null). next_out need not be provided here but must be provided by the
application for the next call of deflate().
@@ -350,8 +350,7 @@ extern int deflateInit2 __P((z_stream *strm,
reset by the library in this case.
deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was
not enough memory, Z_STREAM_ERROR if the stream state was inconsistent
(such as zalloc being NULL) or the parameters are invalid (such as
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().
@@ -406,7 +405,7 @@ extern int inflateInit2 __P((z_stream *strm,
If next_out is not null, the library will use this buffer for the history
buffer; the buffer must either be large enough to hold the entire output
data, or have at least 1<<(windowBits-1) bytes. If next_out is null, the
data, or have at least 1<<windowBits bytes. If next_out is null, the
library will allocate its own buffer (and leave next_out null). next_in
need not be provided here but must be provided by the application for the
next call of inflate().
@@ -418,9 +417,8 @@ extern int inflateInit2 __P((z_stream *strm,
avail_out is zero and all output has been consumed.
inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was
not enough memory, Z_STREAM_ERROR if the stream state was inconsistent
(such as zalloc being NULL) or the parameters are invalid (such as
windowBits < 9). msg is set to null if there is no error message.
not enough memory, Z_STREAM_ERROR if a parameter is invalid (such as
windowBits < 8). msg is set to null if there is no error message.
inflateInit2 does not perform any compression: this will be done by
inflate().
*/
@@ -585,7 +583,7 @@ extern uLong crc32 __P((uLong crc, Byte *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 (0). Pre- and post-conditioning (one's complement) is performed
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: