This commit was generated by cvs2svn to compensate for changes in r33904,

which included commits to RCS files with non-trunk default branches.
This commit is contained in:
Steve Price 1998-02-28 06:04:26 +00:00
commit 9521a6bb06
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=33905
17 changed files with 1165 additions and 420 deletions

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@ -1,6 +1,171 @@
ChangeLog file for zlib
Changes in 1.1.1 (27 Feb 98)
- fix macros _tr_tally_* in deflate.h for debug mode (Glenn Randers-Pehrson)
- remove block truncation heuristic which had very marginal effect for zlib
(smaller lit_bufsize than in gzip 1.2.4) and degraded a little the
compression ratio on some files. This also allows inlining _tr_tally for
matches in deflate_slow.
- added msdos/Makefile.w32 for WIN32 Microsoft Visual C++ (Bob Frazier)
Changes in 1.1.0 (24 Feb 98)
- do not return STREAM_END prematurely in inflate (John Bowler)
- revert to the zlib 1.0.8 inflate to avoid the gcc 2.8.0 bug (Jeremy Buhler)
- compile with -DFASTEST to get compression code optimized for speed only
- in minigzip, try mmap'ing the input file first (Miguel Albrecht)
- increase size of I/O buffers in minigzip.c and gzio.c (not a big gain
on Sun but significant on HP)
- add a pointer to experimental unzip library in README (Gilles Vollant)
- initialize variable gcc in configure (Chris Herborth)
Changes in 1.0.9 (17 Feb 1998)
- added gzputs and gzgets functions
- do not clear eof flag in gzseek (Mark Diekhans)
- fix gzseek for files in transparent mode (Mark Diekhans)
- do not assume that vsprintf returns the number of bytes written (Jens Krinke)
- replace EXPORT with ZEXPORT to avoid conflict with other programs
- added compress2 in zconf.h, zlib.def, zlib.dnt
- new asm code from Gilles Vollant in contrib/asm386
- simplify the inflate code (Mark):
. Replace ZALLOC's in huft_build() with single ZALLOC in inflate_blocks_new()
. ZALLOC the length list in inflate_trees_fixed() instead of using stack
. ZALLOC the value area for huft_build() instead of using stack
. Simplify Z_FINISH check in inflate()
- Avoid gcc 2.8.0 comparison bug a little differently than zlib 1.0.8
- in inftrees.c, avoid cc -O bug on HP (Farshid Elahi)
- in zconf.h move the ZLIB_DLL stuff earlier to avoid problems with
the declaration of FAR (Gilles VOllant)
- install libz.so* with mode 755 (executable) instead of 644 (Marc Lehmann)
- read_buf buf parameter of type Bytef* instead of charf*
- zmemcpy parameters are of type Bytef*, not charf* (Joseph Strout)
- do not redeclare unlink in minigzip.c for WIN32 (John Bowler)
- fix check for presence of directories in "make install" (Ian Willis)
Changes in 1.0.8 (27 Jan 1998)
- fixed offsets in contrib/asm386/gvmat32.asm (Gilles Vollant)
- fix gzgetc and gzputc for big endian systems (Markus Oberhumer)
- added compress2() to allow setting the compression level
- include sys/types.h to get off_t on some systems (Marc Lehmann & QingLong)
- use constant arrays for the static trees in trees.c instead of computing
them at run time (thanks to Ken Raeburn for this suggestion). To create
trees.h, compile with GEN_TREES_H and run "make test".
- check return code of example in "make test" and display result
- pass minigzip command line options to file_compress
- simplifying code of inflateSync to avoid gcc 2.8 bug
- support CC="gcc -Wall" in configure -s (QingLong)
- avoid a flush caused by ftell in gzopen for write mode (Ken Raeburn)
- fix test for shared library support to avoid compiler warnings
- zlib.lib -> zlib.dll in msdos/zlib.rc (Gilles Vollant)
- check for TARGET_OS_MAC in addition to MACOS (Brad Pettit)
- do not use fdopen for Metrowerks on Mac (Brad Pettit))
- add checks for gzputc and gzputc in example.c
- avoid warnings in gzio.c and deflate.c (Andreas Kleinert)
- use const for the CRC table (Ken Raeburn)
- fixed "make uninstall" for shared libraries
- use Tracev instead of Trace in infblock.c
- in example.c use correct compressed length for test_sync
- suppress +vnocompatwarnings in configure for HPUX (not always supported)
Changes in 1.0.7 (20 Jan 1998)
- fix gzseek which was broken in write mode
- return error for gzseek to negative absolute position
- fix configure for Linux (Chun-Chung Chen)
- increase stack space for MSC (Tim Wegner)
- get_crc_table and inflateSyncPoint are EXPORTed (Gilles Vollant)
- define EXPORTVA for gzprintf (Gilles Vollant)
- added man page zlib.3 (Rick Rodgers)
- for contrib/untgz, fix makedir() and improve Makefile
- check gzseek in write mode in example.c
- allocate extra buffer for seeks only if gzseek is actually called
- avoid signed/unsigned comparisons (Tim Wegner, Gilles Vollant)
- add inflateSyncPoint in zconf.h
- fix list of exported functions in nt/zlib.dnt and mdsos/zlib.def
Changes in 1.0.6 (19 Jan 1998)
- add functions gzprintf, gzputc, gzgetc, gztell, gzeof, gzseek, gzrewind and
gzsetparams (thanks to Roland Giersig and Kevin Ruland for some of this code)
- Fix a deflate bug occuring only with compression level 0 (thanks to
Andy Buckler for finding this one).
- In minigzip, pass transparently also the first byte for .Z files.
- return Z_BUF_ERROR instead of Z_OK if output buffer full in uncompress()
- check Z_FINISH in inflate (thanks to Marc Schluper)
- Implement deflateCopy (thanks to Adam Costello)
- make static libraries by default in configure, add --shared option.
- move MSDOS or Windows specific files to directory msdos
- suppress the notion of partial flush to simplify the interface
(but the symbol Z_PARTIAL_FLUSH is kept for compatibility with 1.0.4)
- suppress history buffer provided by application to simplify the interface
(this feature was not implemented anyway in 1.0.4)
- next_in and avail_in must be initialized before calling inflateInit or
inflateInit2
- add EXPORT in all exported functions (for Windows DLL)
- added Makefile.nt (thanks to Stephen Williams)
- added the unsupported "contrib" directory:
contrib/asm386/ by Gilles Vollant <info@winimage.com>
386 asm code replacing longest_match().
contrib/iostream/ by Kevin Ruland <kevin@rodin.wustl.edu>
A C++ I/O streams interface to the zlib gz* functions
contrib/iostream2/ by Tyge Løvset <Tyge.Lovset@cmr.no>
Another C++ I/O streams interface
contrib/untgz/ by "Pedro A. Aranda Guti\irrez" <paag@tid.es>
A very simple tar.gz file extractor using zlib
contrib/visual-basic.txt by Carlos Rios <c_rios@sonda.cl>
How to use compress(), uncompress() and the gz* functions from VB.
- pass params -f (filtered data), -h (huffman only), -1 to -9 (compression
level) in minigzip (thanks to Tom Lane)
- use const for rommable constants in deflate
- added test for gzseek and gztell in example.c
- add undocumented function inflateSyncPoint() (hack for Paul Mackerras)
- add undocumented function zError to convert error code to string
(for Tim Smithers)
- Allow compilation of gzio with -DNO_DEFLATE to avoid the compression code.
- Use default memcpy for Symantec MSDOS compiler.
- Add EXPORT keyword for check_func (needed for Windows DLL)
- add current directory to LD_LIBRARY_PATH for "make test"
- create also a link for libz.so.1
- added support for FUJITSU UXP/DS (thanks to Toshiaki Nomura)
- use $(SHAREDLIB) instead of libz.so in Makefile.in (for HPUX)
- added -soname for Linux in configure (Chun-Chung Chen,
- assign numbers to the exported functions in zlib.def (for Windows DLL)
- add advice in zlib.h for best usage of deflateSetDictionary
- work around compiler bug on Atari (cast Z_NULL in call of s->checkfn)
- allow compilation with ANSI keywords only enabled for TurboC in large model
- avoid "versionString"[0] (Borland bug)
- add NEED_DUMMY_RETURN for Borland
- use variable z_verbose for tracing in debug mode (Peter Deutsch).
- allow compilation with CC
- defined STDC for OS/2 (David Charlap)
- limit external names to 8 chars for MVS (Thomas Lund)
- in minigzip.c, use static buffers only for 16-bit systems
- fix suffix check for "minigzip -d foo.gz"
- do not return an error for the 2nd of two consecutive gzflush() (Felix Lee)
- use _fdopen instead of fdopen for MSC >= 6.0 (Thomas Fanslau)
- added makelcc.bat for lcc-win32 (Tom St Denis)
- in Makefile.dj2, use copy and del instead of install and rm (Frank Donahoe)
- Avoid expanded $Id$. Use "rcs -kb" or "cvs admin -kb" to avoid Id expansion.
- check for unistd.h in configure (for off_t)
- remove useless check parameter in inflate_blocks_free
- avoid useless assignment of s->check to itself in inflate_blocks_new
- do not flush twice in gzclose (thanks to Ken Raeburn)
- rename FOPEN as F_OPEN to avoid clash with /usr/include/sys/file.h
- use NO_ERRNO_H instead of enumeration of operating systems with errno.h
- work around buggy fclose on pipes for HP/UX
- support zlib DLL with BORLAND C++ 5.0 (thanks to Glenn Randers-Pehrson)
- fix configure if CC is already equal to gcc
Changes in 1.0.5 (3 Jan 98)
- Fix inflate to terminate gracefully when fed corrupted or invalid data
- Use const for rommable constants in inflate
- Eliminate memory leaks on error conditions in inflate
- Removed some vestigial code in inflate
- Update web address in README
Changes in 1.0.4 (24 Jul 96)
- In very rare conditions, deflate(s, Z_FINISH) could fail to produce an EOF
bit, so the decompressor could decompress all the correct data but went

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@ -1,15 +1,16 @@
zlib 1.0.4 is a general purpose data compression library. All the code
is reentrant (thread safe). The data format used by the zlib library
zlib 1.1.1 is a general purpose data compression library. All the code
is thread safe. The data format used by the zlib library
is described by RFCs (Request for Comments) 1950 to 1952 in the files
ftp://ds.internic.net/rfc/rfc1950.txt (zlib format), rfc1951.txt (deflate
format) and rfc1952.txt (gzip format). These documents are also available in
other formats from ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html
All functions of the compression library are documented in the file
zlib.h. A usage example of the library is given in the file example.c
which also tests that the library is working correctly. Another
example is given in the file minigzip.c. The compression library itself
is composed of all source files except example.c and minigzip.c.
All functions of the compression library are documented in the file zlib.h
(volunteer to write man pages welcome, contact jloup@gzip.org). A usage
example of the library is given in the file example.c which also tests that
the library is working correctly. Another example is given in the file
minigzip.c. The compression library itself is composed of all source files
except example.c and minigzip.c.
To compile all files and run the test program, follow the instructions
given at the top of Makefile. In short "make test; make install"
@ -18,45 +19,72 @@ makefiles such as Makefile.msc; for VMS, use Make_vms.com or descrip.mms.
Questions about zlib should be sent to <zlib@quest.jpl.nasa.gov> or,
if this fails, to the addresses given below in the Copyright section.
The zlib home page is http://quest.jpl.nasa.gov/zlib/
The zlib home page is http://www.cdrom.com/pub/infozip/zlib/
The official zlib ftp site is ftp://ftp.cdrom.com/pub/infozip/zlib/
Mark Nelson wrote an article about zlib for the Jan. 1997 issue of
Dr. Dobb's Journal; a copy of the article is available in
http://web2.airmail.net/markn/articles/zlibtool/zlibtool.htm
The changes made in version 1.0.4 are documented in the file ChangeLog.
The main changes since 1.0.3 are:
The changes made in version 1.1.1 are documented in the file ChangeLog.
The main changes since 1.1.0 are:
- In very rare conditions, deflate(s, Z_FINISH) could fail to produce an EOF
bit, so the decompressor could decompress all the correct data but went
on to attempt decompressing extra garbage data. This affected minigzip too.
- zlibVersion and gzerror return const char* (needed for DLL)
- port to RISCOS (no fdopen, no multiple dots, no unlink, no fileno)
- fix macros _tr_tally_* in deflate.h for debug mode (Glenn Randers-Pehrson)
- remove block truncation heuristic which had very marginal effect for zlib
(smaller lit_bufsize than in gzip 1.2.4) and degraded a little the
compression ratio on some files. This also allows inlining _tr_tally for
matches in deflate_slow.
Unsupported third party contributions are provided in directory "contrib".
A Java implementation of zlib is available in the Java Development Kit 1.1
http://www.javasoft.com/products/JDK/1.1/docs/api/Package-java.util.zip.html
See the zlib home page http://www.cdrom.com/pub/infozip/zlib/ for details.
A Perl interface to zlib written by Paul Marquess <pmarquess@bfsec.bt.co.uk>
is in the CPAN (Comprehensive Perl Archive Network) sites, such as:
ftp://ftp.cis.ufl.edu/pub/perl/CPAN/modules/by-module/Compress/Compress-Zlib*
A Python interface to zlib written by A.M. Kuchling <amk@magnet.com>
is available from the Python Software Association sites, such as:
ftp://ftp.python.org/pub/python/contrib/Encoding/zlib*.tar.gz
An experimental package to read files in .zip format, written on top of
zlib by Gilles Vollant <info@winimage.com>, is available at
http://www.winimage.com/zLibDll/unzip.html
Notes for some targets:
- For Turbo C the small model is supported only with reduced performance to
avoid any far allocation; it was tested with -DMAX_WBITS=11 -DMAX_MEM_LEVEL=3
- To build a Windows DLL version, include in a DLL project zlib.def, zlib.rc
and all .c files except example.c and minigzip.c; compile with -DZLIB_DLL
The zlib DLL support was initially done by Alessandro Iacopetti and is
now maintained by Gilles Vollant <info@winimage.com>. Check the zlib DLL
home page at http://www.winimage.com/zLibDll
- For 64-bit Iris, deflate.c must be compiled without any optimization.
From Visual Basic, you can call the DLL functions which do not take
a structure as argument: compress, uncompress and all gz* functions.
See contrib/visual-basic.txt for more information.
I don't know how to handle structures in Visual Basic, sorry.
- For 64-bit Irix, deflate.c must be compiled without any optimization.
With -O, one libpng test fails. The test works in 32 bit mode (with
the -32 compiler flag). The compiler bug has been reported to SGI.
the -n32 compiler flag). The compiler bug has been reported to SGI.
- zlib doesn't work with gcc 2.6.3 on a DEC 3000/300LX under OSF/1 2.1
it works when compiled with cc.
- zlib doesn't work on HP-UX 9.05 with one cc compiler (the one not
accepting the -O option). It works with the other cc compiler.
- zlib doesn't work on HP-UX 9.05 with some versions of /bin/cc. It works
with other compilers. Use "make test" to check your compiler.
- To build a Windows DLL version, include in a DLL project zlib.def, zlib.rc
and all .c files except example.c and minigzip.c; compile with -DZLIB_DLL
For help on building a zlib DLL, contact Alessandro Iacopetti
<iaco@email.alessandria.alpcom.it> http://lisa.unial.it/iaco ,
or contact Brad Clarke <bclarke@cyberus.ca>.
- For shared memory multiprocessors, the decompression code assumes that
writes to pointers are atomic. Also the functions zalloc and zfree passed
to deflateInit must be multi-threaded in this case.
- gzdopen is not supported on RISCOS
- gzdopen is not supported on RISCOS, BEOS and by some Mac compilers.
- For Turbo C the small model is supported only with reduced performance to
avoid any far allocation; it was tested with -DMAX_WBITS=11 -DMAX_MEM_LEVEL=3
Acknowledgments:
@ -68,7 +96,7 @@ Acknowledgments:
Copyright notice:
(C) 1995-1996 Jean-loup Gailly and Mark Adler
(C) 1995-1998 Jean-loup Gailly and Mark Adler
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
@ -87,7 +115,7 @@ Copyright notice:
3. This notice may not be removed or altered from any source distribution.
Jean-loup Gailly Mark Adler
gzip@prep.ai.mit.edu madler@alumni.caltech.edu
jloup@gzip.org madler@alumni.caltech.edu
If you use the zlib library in a product, we would appreciate *not*
receiving lengthy legal documents to sign. The sources are provided

213
lib/libz/algorithm.txt Normal file
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@ -0,0 +1,213 @@
1. Compression algorithm (deflate)
The deflation algorithm used by gzip (also zip and zlib) is a variation of
LZ77 (Lempel-Ziv 1977, see reference below). It finds duplicated strings in
the input data. The second occurrence of a string is replaced by a
pointer to the previous string, in the form of a pair (distance,
length). Distances are limited to 32K bytes, and lengths are limited
to 258 bytes. When a string does not occur anywhere in the previous
32K bytes, it is emitted as a sequence of literal bytes. (In this
description, `string' must be taken as an arbitrary sequence of bytes,
and is not restricted to printable characters.)
Literals or match lengths are compressed with one Huffman tree, and
match distances are compressed with another tree. The trees are stored
in a compact form at the start of each block. The blocks can have any
size (except that the compressed data for one block must fit in
available memory). A block is terminated when deflate() determines that
it would be useful to start another block with fresh trees. (This is
somewhat similar to the behavior of LZW-based _compress_.)
Duplicated strings are found using a hash table. All input strings of
length 3 are inserted in the hash table. A hash index is computed for
the next 3 bytes. If the hash chain for this index is not empty, all
strings in the chain are compared with the current input string, and
the longest match is selected.
The hash chains are searched starting with the most recent strings, to
favor small distances and thus take advantage of the Huffman encoding.
The hash chains are singly linked. There are no deletions from the
hash chains, the algorithm simply discards matches that are too old.
To avoid a worst-case situation, very long hash chains are arbitrarily
truncated at a certain length, determined by a runtime option (level
parameter of deflateInit). So deflate() does not always find the longest
possible match but generally finds a match which is long enough.
deflate() also defers the selection of matches with a lazy evaluation
mechanism. After a match of length N has been found, deflate() searches for
a longer match at the next input byte. If a longer match is found, the
previous match is truncated to a length of one (thus producing a single
literal byte) and the process of lazy evaluation begins again. Otherwise,
the original match is kept, and the next match search is attempted only N
steps later.
The lazy match evaluation is also subject to a runtime parameter. If
the current match is long enough, deflate() reduces the search for a longer
match, thus speeding up the whole process. If compression ratio is more
important than speed, deflate() attempts a complete second search even if
the first match is already long enough.
The lazy match evaluation is not performed for the fastest compression
modes (level parameter 1 to 3). For these fast modes, new strings
are inserted in the hash table only when no match was found, or
when the match is not too long. This degrades the compression ratio
but saves time since there are both fewer insertions and fewer searches.
2. Decompression algorithm (inflate)
2.1 Introduction
The real question is, given a Huffman tree, how to decode fast. The most
important realization is that shorter codes are much more common than
longer codes, so pay attention to decoding the short codes fast, and let
the long codes take longer to decode.
inflate() sets up a first level table that covers some number of bits of
input less than the length of longest code. It gets that many bits from the
stream, and looks it up in the table. The table will tell if the next
code is that many bits or less and how many, and if it is, it will tell
the value, else it will point to the next level table for which inflate()
grabs more bits and tries to decode a longer code.
How many bits to make the first lookup is a tradeoff between the time it
takes to decode and the time it takes to build the table. If building the
table took no time (and if you had infinite memory), then there would only
be a first level table to cover all the way to the longest code. However,
building the table ends up taking a lot longer for more bits since short
codes are replicated many times in such a table. What inflate() does is
simply to make the number of bits in the first table a variable, and set it
for the maximum speed.
inflate() sends new trees relatively often, so it is possibly set for a
smaller first level table than an application that has only one tree for
all the data. For inflate, which has 286 possible codes for the
literal/length tree, the size of the first table is nine bits. Also the
distance trees have 30 possible values, and the size of the first table is
six bits. Note that for each of those cases, the table ended up one bit
longer than the ``average'' code length, i.e. the code length of an
approximately flat code which would be a little more than eight bits for
286 symbols and a little less than five bits for 30 symbols. It would be
interesting to see if optimizing the first level table for other
applications gave values within a bit or two of the flat code size.
2.2 More details on the inflate table lookup
Ok, you want to know what this cleverly obfuscated inflate tree actually
looks like. You are correct that it's not a Huffman tree. It is simply a
lookup table for the first, let's say, nine bits of a Huffman symbol. The
symbol could be as short as one bit or as long as 15 bits. If a particular
symbol is shorter than nine bits, then that symbol's translation is duplicated
in all those entries that start with that symbol's bits. For example, if the
symbol is four bits, then it's duplicated 32 times in a nine-bit table. If a
symbol is nine bits long, it appears in the table once.
If the symbol is longer than nine bits, then that entry in the table points
to another similar table for the remaining bits. Again, there are duplicated
entries as needed. The idea is that most of the time the symbol will be short
and there will only be one table look up. (That's whole idea behind data
compression in the first place.) For the less frequent long symbols, there
will be two lookups. If you had a compression method with really long
symbols, you could have as many levels of lookups as is efficient. For
inflate, two is enough.
So a table entry either points to another table (in which case nine bits in
the above example are gobbled), or it contains the translation for the symbol
and the number of bits to gobble. Then you start again with the next
ungobbled bit.
You may wonder: why not just have one lookup table for how ever many bits the
longest symbol is? The reason is that if you do that, you end up spending
more time filling in duplicate symbol entries than you do actually decoding.
At least for deflate's output that generates new trees every several 10's of
kbytes. You can imagine that filling in a 2^15 entry table for a 15-bit code
would take too long if you're only decoding several thousand symbols. At the
other extreme, you could make a new table for every bit in the code. In fact,
that's essentially a Huffman tree. But then you spend two much time
traversing the tree while decoding, even for short symbols.
So the number of bits for the first lookup table is a trade of the time to
fill out the table vs. the time spent looking at the second level and above of
the table.
Here is an example, scaled down:
The code being decoded, with 10 symbols, from 1 to 6 bits long:
A: 0
B: 10
C: 1100
D: 11010
E: 11011
F: 11100
G: 11101
H: 11110
I: 111110
J: 111111
Let's make the first table three bits long (eight entries):
000: A,1
001: A,1
010: A,1
011: A,1
100: B,2
101: B,2
110: -> table X (gobble 3 bits)
111: -> table Y (gobble 3 bits)
Each entry is what the bits decode to and how many bits that is, i.e. how
many bits to gobble. Or the entry points to another table, with the number of
bits to gobble implicit in the size of the table.
Table X is two bits long since the longest code starting with 110 is five bits
long:
00: C,1
01: C,1
10: D,2
11: E,2
Table Y is three bits long since the longest code starting with 111 is six
bits long:
000: F,2
001: F,2
010: G,2
011: G,2
100: H,2
101: H,2
110: I,3
111: J,3
So what we have here are three tables with a total of 20 entries that had to
be constructed. That's compared to 64 entries for a single table. Or
compared to 16 entries for a Huffman tree (six two entry tables and one four
entry table). Assuming that the code ideally represents the probability of
the symbols, it takes on the average 1.25 lookups per symbol. That's compared
to one lookup for the single table, or 1.66 lookups per symbol for the
Huffman tree.
There, I think that gives you a picture of what's going on. For inflate, the
meaning of a particular symbol is often more than just a letter. It can be a
byte (a "literal"), or it can be either a length or a distance which
indicates a base value and a number of bits to fetch after the code that is
added to the base value. Or it might be the special end-of-block code. The
data structures created in inftrees.c try to encode all that information
compactly in the tables.
Jean-loup Gailly Mark Adler
jloup@gzip.org madler@alumni.caltech.edu
References:
[LZ77] Ziv J., Lempel A., ``A Universal Algorithm for Sequential Data
Compression,'' IEEE Transactions on Information Theory, Vol. 23, No. 3,
pp. 337-343.
``DEFLATE Compressed Data Format Specification'' available in
ftp://ds.internic.net/rfc/rfc1951.txt

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@ -1,5 +1,5 @@
/* infblock.c -- interpret and process block types to last block
* Copyright (C) 1995-1996 Mark Adler
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@ -66,23 +66,19 @@ inflate_blocks_statef *s;
z_streamp z;
uLongf *c;
{
if (s->checkfn != Z_NULL)
if (c != Z_NULL)
*c = s->check;
if (s->mode == BTREE || s->mode == DTREE)
ZFREE(z, s->sub.trees.blens);
if (s->mode == CODES)
{
inflate_codes_free(s->sub.decode.codes, z);
inflate_trees_free(s->sub.decode.td, z);
inflate_trees_free(s->sub.decode.tl, z);
}
s->mode = TYPE;
s->bitk = 0;
s->bitb = 0;
s->read = s->write = s->window;
if (s->checkfn != Z_NULL)
z->adler = s->check = (*s->checkfn)(0L, Z_NULL, 0);
Trace((stderr, "inflate: blocks reset\n"));
z->adler = s->check = (*s->checkfn)(0L, (const Bytef *)Z_NULL, 0);
Tracev((stderr, "inflate: blocks reset\n"));
}
@ -96,23 +92,27 @@ uInt w;
if ((s = (inflate_blocks_statef *)ZALLOC
(z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
return s;
if ((s->hufts =
(inflate_huft *)ZALLOC(z, sizeof(inflate_huft), MANY)) == Z_NULL)
{
ZFREE(z, s);
return Z_NULL;
}
if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
{
ZFREE(z, s->hufts);
ZFREE(z, s);
return Z_NULL;
}
s->end = s->window + w;
s->checkfn = c;
s->mode = TYPE;
Trace((stderr, "inflate: blocks allocated\n"));
inflate_blocks_reset(s, z, &s->check);
Tracev((stderr, "inflate: blocks allocated\n"));
inflate_blocks_reset(s, z, Z_NULL);
return s;
}
#ifdef DEBUG
extern uInt inflate_hufts;
#endif
int inflate_blocks(s, z, r)
inflate_blocks_statef *s;
z_streamp z;
@ -139,7 +139,7 @@ int r;
switch (t >> 1)
{
case 0: /* stored */
Trace((stderr, "inflate: stored block%s\n",
Tracev((stderr, "inflate: stored block%s\n",
s->last ? " (last)" : ""));
DUMPBITS(3)
t = k & 7; /* go to byte boundary */
@ -147,27 +147,25 @@ int r;
s->mode = LENS; /* get length of stored block */
break;
case 1: /* fixed */
Trace((stderr, "inflate: fixed codes block%s\n",
Tracev((stderr, "inflate: fixed codes block%s\n",
s->last ? " (last)" : ""));
{
uInt bl, bd;
inflate_huft *tl, *td;
inflate_trees_fixed(&bl, &bd, &tl, &td);
inflate_trees_fixed(&bl, &bd, &tl, &td, z);
s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
if (s->sub.decode.codes == Z_NULL)
{
r = Z_MEM_ERROR;
LEAVE
}
s->sub.decode.tl = Z_NULL; /* don't try to free these */
s->sub.decode.td = Z_NULL;
}
DUMPBITS(3)
s->mode = CODES;
break;
case 2: /* dynamic */
Trace((stderr, "inflate: dynamic codes block%s\n",
Tracev((stderr, "inflate: dynamic codes block%s\n",
s->last ? " (last)" : ""));
DUMPBITS(3)
s->mode = TABLE;
@ -224,8 +222,6 @@ int r;
}
#endif
t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
if (t < 19)
t = 19;
if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
{
r = Z_MEM_ERROR;
@ -246,7 +242,7 @@ int r;
s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
s->sub.trees.bb = 7;
t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
&s->sub.trees.tb, z);
&s->sub.trees.tb, s->hufts, z);
if (t != Z_OK)
{
ZFREE(z, s->sub.trees.blens);
@ -288,7 +284,6 @@ int r;
if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
(c == 16 && i < 1))
{
inflate_trees_free(s->sub.trees.tb, z);
ZFREE(z, s->sub.trees.blens);
s->mode = BAD;
z->msg = (char*)"invalid bit length repeat";
@ -302,7 +297,6 @@ int r;
s->sub.trees.index = i;
}
}
inflate_trees_free(s->sub.trees.tb, z);
s->sub.trees.tb = Z_NULL;
{
uInt bl, bd;
@ -312,11 +306,9 @@ int r;
bl = 9; /* must be <= 9 for lookahead assumptions */
bd = 6; /* must be <= 9 for lookahead assumptions */
t = s->sub.trees.table;
#ifdef DEBUG
inflate_hufts = 0;
#endif
t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
s->sub.trees.blens, &bl, &bd, &tl, &td, z);
s->sub.trees.blens, &bl, &bd, &tl, &td,
s->hufts, z);
ZFREE(z, s->sub.trees.blens);
if (t != Z_OK)
{
@ -325,18 +317,13 @@ int r;
r = t;
LEAVE
}
Tracev((stderr, "inflate: trees ok, %d * %d bytes used\n",
inflate_hufts, sizeof(inflate_huft)));
Tracev((stderr, "inflate: trees ok\n"));
if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
{
inflate_trees_free(td, z);
inflate_trees_free(tl, z);
r = Z_MEM_ERROR;
LEAVE
}
s->sub.decode.codes = c;
s->sub.decode.tl = tl;
s->sub.decode.td = td;
}
s->mode = CODES;
case CODES:
@ -345,8 +332,6 @@ int r;
return inflate_flush(s, z, r);
r = Z_OK;
inflate_codes_free(s->sub.decode.codes, z);
inflate_trees_free(s->sub.decode.td, z);
inflate_trees_free(s->sub.decode.tl, z);
LOAD
Tracev((stderr, "inflate: codes end, %lu total out\n",
z->total_out + (q >= s->read ? q - s->read :
@ -382,15 +367,15 @@ int r;
}
int inflate_blocks_free(s, z, c)
int inflate_blocks_free(s, z)
inflate_blocks_statef *s;
z_streamp z;
uLongf *c;
{
inflate_blocks_reset(s, z, c);
inflate_blocks_reset(s, z, Z_NULL);
ZFREE(z, s->window);
ZFREE(z, s->hufts);
ZFREE(z, s);
Trace((stderr, "inflate: blocks freed\n"));
Tracev((stderr, "inflate: blocks freed\n"));
return Z_OK;
}
@ -400,6 +385,17 @@ inflate_blocks_statef *s;
const Bytef *d;
uInt n;
{
zmemcpy((charf *)s->window, d, n);
zmemcpy(s->window, d, n);
s->read = s->write = s->window + n;
}
/* Returns true if inflate is currently at the end of a block generated
* by Z_SYNC_FLUSH or Z_FULL_FLUSH.
* IN assertion: s != Z_NULL
*/
int inflate_blocks_sync_point(s)
inflate_blocks_statef *s;
{
return s->mode == LENS;
}

View File

@ -1,5 +1,5 @@
/* infblock.h -- header to use infblock.c
* Copyright (C) 1995-1996 Mark Adler
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@ -28,10 +28,12 @@ extern void inflate_blocks_reset OF((
extern int inflate_blocks_free OF((
inflate_blocks_statef *,
z_streamp ,
uLongf *)); /* check value on output */
z_streamp));
extern void inflate_set_dictionary OF((
inflate_blocks_statef *s,
const Bytef *d, /* dictionary */
uInt n)); /* dictionary length */
extern int inflate_blocks_sync_point OF((
inflate_blocks_statef *s));

View File

@ -1,5 +1,5 @@
/* infcodes.c -- process literals and length/distance pairs
* Copyright (C) 1995-1996 Mark Adler
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@ -16,11 +16,7 @@
#define exop word.what.Exop
#define bits word.what.Bits
/* inflate codes private state */
struct inflate_codes_state {
/* mode */
enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
typedef enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
START, /* x: set up for LEN */
LEN, /* i: get length/literal/eob next */
LENEXT, /* i: getting length extra (have base) */
@ -31,7 +27,13 @@ struct inflate_codes_state {
WASH, /* o: got eob, possibly still output waiting */
END, /* x: got eob and all data flushed */
BADCODE} /* x: got error */
mode; /* current inflate_codes mode */
inflate_codes_mode;
/* inflate codes private state */
struct inflate_codes_state {
/* mode */
inflate_codes_mode mode; /* current inflate_codes mode */
/* mode dependent information */
uInt len;
@ -235,6 +237,9 @@ int r;
r = Z_STREAM_ERROR;
LEAVE
}
#ifdef NEED_DUMMY_RETURN
return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
#endif
}

View File

@ -1,5 +1,5 @@
/* infcodes.h -- header to use infcodes.c
* Copyright (C) 1995-1996 Mark Adler
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/

View File

@ -1,5 +1,5 @@
/* inffast.c -- process literals and length/distance pairs fast
* Copyright (C) 1995-1996 Mark Adler
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/

View File

@ -1,5 +1,5 @@
/* inffast.h -- header to use inffast.c
* Copyright (C) 1995-1996 Mark Adler
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/

View File

@ -1,5 +1,5 @@
/* inflate.c -- zlib interface to inflate modules
* Copyright (C) 1995-1996 Mark Adler
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@ -8,11 +8,7 @@
struct inflate_blocks_state {int dummy;}; /* for buggy compilers */
/* inflate private state */
struct internal_state {
/* mode */
enum {
typedef enum {
METHOD, /* waiting for method byte */
FLAG, /* waiting for flag byte */
DICT4, /* four dictionary check bytes to go */
@ -27,7 +23,13 @@ struct internal_state {
CHECK1, /* one check byte to go */
DONE, /* finished check, done */
BAD} /* got an error--stay here */
mode; /* current inflate mode */
inflate_mode;
/* inflate private state */
struct internal_state {
/* mode */
inflate_mode mode; /* current inflate mode */
/* mode dependent information */
union {
@ -48,39 +50,35 @@ struct internal_state {
};
int inflateReset(z)
int ZEXPORT inflateReset(z)
z_streamp z;
{
uLong c;
if (z == Z_NULL || z->state == Z_NULL)
return Z_STREAM_ERROR;
z->total_in = z->total_out = 0;
z->msg = Z_NULL;
z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
inflate_blocks_reset(z->state->blocks, z, &c);
Trace((stderr, "inflate: reset\n"));
inflate_blocks_reset(z->state->blocks, z, Z_NULL);
Tracev((stderr, "inflate: reset\n"));
return Z_OK;
}
int inflateEnd(z)
int ZEXPORT inflateEnd(z)
z_streamp z;
{
uLong c;
if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
return Z_STREAM_ERROR;
if (z->state->blocks != Z_NULL)
inflate_blocks_free(z->state->blocks, z, &c);
inflate_blocks_free(z->state->blocks, z);
ZFREE(z, z->state);
z->state = Z_NULL;
Trace((stderr, "inflate: end\n"));
Tracev((stderr, "inflate: end\n"));
return Z_OK;
}
int inflateInit2_(z, w, version, stream_size)
int ZEXPORT inflateInit2_(z, w, version, stream_size)
z_streamp z;
int w;
const char *version;
@ -129,7 +127,7 @@ int stream_size;
inflateEnd(z);
return Z_MEM_ERROR;
}
Trace((stderr, "inflate: allocated\n"));
Tracev((stderr, "inflate: allocated\n"));
/* reset state */
inflateReset(z);
@ -137,7 +135,7 @@ int stream_size;
}
int inflateInit_(z, version, stream_size)
int ZEXPORT inflateInit_(z, version, stream_size)
z_streamp z;
const char *version;
int stream_size;
@ -146,18 +144,19 @@ int stream_size;
}
#define NEEDBYTE {if(z->avail_in==0)return r;r=Z_OK;}
#define NEEDBYTE {if(z->avail_in==0)return r;r=f;}
#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
int inflate(z, f)
int ZEXPORT inflate(z, f)
z_streamp z;
int f;
{
int r;
uInt b;
if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL || f < 0)
if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL)
return Z_STREAM_ERROR;
f = f == Z_FINISH ? Z_BUF_ERROR : Z_OK;
r = Z_BUF_ERROR;
while (1) switch (z->state->mode)
{
@ -188,11 +187,11 @@ int f;
z->state->sub.marker = 5; /* can't try inflateSync */
break;
}
Trace((stderr, "inflate: zlib header ok\n"));
Tracev((stderr, "inflate: zlib header ok\n"));
if (!(b & PRESET_DICT))
{
z->state->mode = BLOCKS;
break;
break;
}
z->state->mode = DICT4;
case DICT4:
@ -226,9 +225,11 @@ int f;
z->state->sub.marker = 0; /* can try inflateSync */
break;
}
if (r == Z_OK)
r = f;
if (r != Z_STREAM_END)
return r;
r = Z_OK;
r = f;
inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
if (z->state->nowrap)
{
@ -259,7 +260,7 @@ int f;
z->state->sub.marker = 5; /* can't try inflateSync */
break;
}
Trace((stderr, "inflate: zlib check ok\n"));
Tracev((stderr, "inflate: zlib check ok\n"));
z->state->mode = DONE;
case DONE:
return Z_STREAM_END;
@ -268,10 +269,13 @@ int f;
default:
return Z_STREAM_ERROR;
}
#ifdef NEED_DUMMY_RETURN
return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
#endif
}
int inflateSetDictionary(z, dictionary, dictLength)
int ZEXPORT inflateSetDictionary(z, dictionary, dictLength)
z_streamp z;
const Bytef *dictionary;
uInt dictLength;
@ -295,7 +299,7 @@ uInt dictLength;
}
int inflateSync(z)
int ZEXPORT inflateSync(z)
z_streamp z;
{
uInt n; /* number of bytes to look at */
@ -319,7 +323,8 @@ z_streamp z;
/* search */
while (n && m < 4)
{
if (*p == (Byte)(m < 2 ? 0 : 0xff))
static const Byte mark[4] = {0, 0, 0xff, 0xff};
if (*p == mark[m])
m++;
else if (*p)
m = 0;
@ -343,3 +348,19 @@ z_streamp z;
z->state->mode = BLOCKS;
return Z_OK;
}
/* Returns true if inflate is currently at the end of a block generated
* by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
* implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
* but removes the length bytes of the resulting empty stored block. When
* decompressing, PPP checks that at the end of input packet, inflate is
* waiting for these length bytes.
*/
int ZEXPORT inflateSyncPoint(z)
z_streamp z;
{
if (z == Z_NULL || z->state == Z_NULL || z->state->blocks == Z_NULL)
return Z_STREAM_ERROR;
return inflate_blocks_sync_point(z->state->blocks);
}

View File

@ -1,12 +1,13 @@
/* inftrees.c -- generate Huffman trees for efficient decoding
* Copyright (C) 1995-1996 Mark Adler
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "zutil.h"
#include "inftrees.h"
char inflate_copyright[] = " inflate 1.0.4 Copyright 1995-1996 Mark Adler ";
const char inflate_copyright[] =
" inflate 1.1.1 Copyright 1995-1998 Mark Adler ";
/*
If you use the zlib library in a product, an acknowledgment is welcome
in the documentation of your product. If for some reason you cannot
@ -30,12 +31,9 @@ local int huft_build OF((
const uIntf *, /* list of extra bits for non-simple codes */
inflate_huft * FAR*,/* result: starting table */
uIntf *, /* maximum lookup bits (returns actual) */
z_streamp )); /* for zalloc function */
local voidpf falloc OF((
voidpf, /* opaque pointer (not used) */
uInt, /* number of items */
uInt)); /* size of item */
inflate_huft *, /* space for trees */
uInt *, /* hufts used in space */
uIntf * )); /* space for values */
/* Tables for deflate from PKZIP's appnote.txt. */
local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */
@ -89,21 +87,18 @@ local const uInt cpdext[30] = { /* Extra bits for distance codes */
/* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
#define BMAX 15 /* maximum bit length of any code */
#define N_MAX 288 /* maximum number of codes in any set */
#ifdef DEBUG
uInt inflate_hufts;
#endif
local int huft_build(b, n, s, d, e, t, m, zs)
local int huft_build(b, n, s, d, e, t, m, hp, hn, v)
uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
uInt n; /* number of codes (assumed <= N_MAX) */
uInt n; /* number of codes (assumed <= 288) */
uInt s; /* number of simple-valued codes (0..s-1) */
const uIntf *d; /* list of base values for non-simple codes */
const uIntf *e; /* list of extra bits for non-simple codes */
inflate_huft * FAR *t; /* result: starting table */
uIntf *m; /* maximum lookup bits, returns actual */
z_streamp zs; /* for zalloc function */
inflate_huft *hp; /* space for trees */
uInt *hn; /* hufts used in space */
uIntf *v; /* working area: values in order of bit length */
/* Given a list of code lengths and a maximum table size, make a set of
tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
if the given code set is incomplete (the tables are still built in this
@ -120,11 +115,11 @@ z_streamp zs; /* for zalloc function */
register uInt j; /* counter */
register int k; /* number of bits in current code */
int l; /* bits per table (returned in m) */
uInt mask; /* (1 << w) - 1, to avoid cc -O bug on HP */
register uIntf *p; /* pointer into c[], b[], or v[] */
inflate_huft *q; /* points to current table */
struct inflate_huft_s r; /* table entry for structure assignment */
inflate_huft *u[BMAX]; /* table stack */
uInt v[N_MAX]; /* values in order of bit length */
register int w; /* bits before this table == (l * h) */
uInt x[BMAX+1]; /* bit offsets, then code stack */
uIntf *xp; /* pointer into x */
@ -190,7 +185,7 @@ z_streamp zs; /* for zalloc function */
if ((j = *p++) != 0)
v[x[j]++] = i;
} while (++i < n);
n = x[g]; /* set n to length of v */
n = x[g]; /* set n to length of v */
/* Generate the Huffman codes and for each, make the table entries */
@ -232,20 +227,16 @@ z_streamp zs; /* for zalloc function */
}
z = 1 << j; /* table entries for j-bit table */
/* allocate and link in new table */
if ((q = (inflate_huft *)ZALLOC
(zs,z + 1,sizeof(inflate_huft))) == Z_NULL)
{
if (h)
inflate_trees_free(u[0], zs);
/* allocate new table */
if (*hn + z > MANY) /* (note: doesn't matter for fixed) */
return Z_MEM_ERROR; /* not enough memory */
u[h] = q = hp + *hn;
*hn += z;
if (t != Z_NULL) /* first table is returned result */
{
*t = q;
t = Z_NULL;
}
#ifdef DEBUG
inflate_hufts += z + 1;
#endif
*t = q + 1; /* link to list for huft_free() */
*(t = &(q->next)) = Z_NULL;
u[h] = ++q; /* table starts after link */
/* connect to last table, if there is one */
if (h)
@ -285,10 +276,12 @@ z_streamp zs; /* for zalloc function */
i ^= j;
/* backup over finished tables */
while ((i & ((1 << w) - 1)) != x[h])
mask = (1 << w) - 1; /* needed on HP, cc -O bug */
while ((i & mask) != x[h])
{
h--; /* don't need to update q */
w -= l;
mask = (1 << w) - 1;
}
}
}
@ -299,28 +292,34 @@ z_streamp zs; /* for zalloc function */
}
int inflate_trees_bits(c, bb, tb, z)
int inflate_trees_bits(c, bb, tb, hp, z)
uIntf *c; /* 19 code lengths */
uIntf *bb; /* bits tree desired/actual depth */
inflate_huft * FAR *tb; /* bits tree result */
z_streamp z; /* for zfree function */
inflate_huft *hp; /* space for trees */
z_streamp z; /* for messages */
{
int r;
uInt hn = 0; /* hufts used in space */
uIntf *v; /* work area for huft_build */
r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z);
if ((v = (uIntf*)ZALLOC(z, 19, sizeof(uInt))) == Z_NULL)
return Z_MEM_ERROR;
r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL,
tb, bb, hp, &hn, v);
if (r == Z_DATA_ERROR)
z->msg = (char*)"oversubscribed dynamic bit lengths tree";
else if (r == Z_BUF_ERROR || *bb == 0)
{
inflate_trees_free(*tb, z);
z->msg = (char*)"incomplete dynamic bit lengths tree";
r = Z_DATA_ERROR;
}
ZFREE(z, v);
return r;
}
int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z)
int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, hp, z)
uInt nl; /* number of literal/length codes */
uInt nd; /* number of distance codes */
uIntf *c; /* that many (total) code lengths */
@ -328,27 +327,34 @@ uIntf *bl; /* literal desired/actual bit depth */
uIntf *bd; /* distance desired/actual bit depth */
inflate_huft * FAR *tl; /* literal/length tree result */
inflate_huft * FAR *td; /* distance tree result */
z_streamp z; /* for zfree function */
inflate_huft *hp; /* space for trees */
z_streamp z; /* for messages */
{
int r;
uInt hn = 0; /* hufts used in space */
uIntf *v; /* work area for huft_build */
/* allocate work area */
if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
return Z_MEM_ERROR;
/* build literal/length tree */
r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z);
r = huft_build(c, nl, 257, cplens, cplext, tl, bl, hp, &hn, v);
if (r != Z_OK || *bl == 0)
{
if (r == Z_DATA_ERROR)
z->msg = (char*)"oversubscribed literal/length tree";
else if (r != Z_MEM_ERROR)
{
inflate_trees_free(*tl, z);
z->msg = (char*)"incomplete literal/length tree";
r = Z_DATA_ERROR;
}
ZFREE(z, v);
return r;
}
/* build distance tree */
r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z);
r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, hp, &hn, v);
if (r != Z_OK || (*bd == 0 && nl > 257))
{
if (r == Z_DATA_ERROR)
@ -358,7 +364,6 @@ z_streamp z; /* for zfree function */
r = Z_OK;
}
#else
inflate_trees_free(*td, z);
z->msg = (char*)"incomplete distance tree";
r = Z_DATA_ERROR;
}
@ -367,19 +372,20 @@ z_streamp z; /* for zfree function */
z->msg = (char*)"empty distance tree with lengths";
r = Z_DATA_ERROR;
}
inflate_trees_free(*tl, z);
ZFREE(z, v);
return r;
#endif
}
/* done */
ZFREE(z, v);
return Z_OK;
}
/* build fixed tables only once--keep them here */
local int fixed_built = 0;
#define FIXEDH 530 /* number of hufts used by fixed tables */
#define FIXEDH 424 /* number of hufts used by fixed tables */
local inflate_huft fixed_mem[FIXEDH];
local uInt fixed_bl;
local uInt fixed_bd;
@ -387,36 +393,29 @@ local inflate_huft *fixed_tl;
local inflate_huft *fixed_td;
local voidpf falloc(q, n, s)
voidpf q; /* opaque pointer */
uInt n; /* number of items */
uInt s; /* size of item */
{
Assert(s == sizeof(inflate_huft) && n <= *(intf *)q,
"inflate_trees falloc overflow");
*(intf *)q -= n+s-s; /* s-s to avoid warning */
return (voidpf)(fixed_mem + *(intf *)q);
}
int inflate_trees_fixed(bl, bd, tl, td)
int inflate_trees_fixed(bl, bd, tl, td, z)
uIntf *bl; /* literal desired/actual bit depth */
uIntf *bd; /* distance desired/actual bit depth */
inflate_huft * FAR *tl; /* literal/length tree result */
inflate_huft * FAR *td; /* distance tree result */
z_streamp z; /* for memory allocation */
{
/* build fixed tables if not already (multiple overlapped executions ok) */
if (!fixed_built)
{
int k; /* temporary variable */
unsigned c[288]; /* length list for huft_build */
z_stream z; /* for falloc function */
int f = FIXEDH; /* number of hufts left in fixed_mem */
uInt f = 0; /* number of hufts used in fixed_mem */
uIntf *c; /* length list for huft_build */
uIntf *v; /* work area for huft_build */
/* set up fake z_stream for memory routines */
z.zalloc = falloc;
z.zfree = Z_NULL;
z.opaque = (voidpf)&f;
/* allocate memory */
if ((c = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
return Z_MEM_ERROR;
if ((v = (uIntf*)ZALLOC(z, 288, sizeof(uInt))) == Z_NULL)
{
ZFREE(z, c);
return Z_MEM_ERROR;
}
/* literal table */
for (k = 0; k < 144; k++)
@ -428,16 +427,19 @@ inflate_huft * FAR *td; /* distance tree result */
for (; k < 288; k++)
c[k] = 8;
fixed_bl = 7;
huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z);
huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl,
fixed_mem, &f, v);
/* distance table */
for (k = 0; k < 30; k++)
c[k] = 5;
fixed_bd = 5;
huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z);
huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd,
fixed_mem, &f, v);
/* done */
Assert(f == 0, "invalid build of fixed tables");
ZFREE(z, v);
ZFREE(z, c);
fixed_built = 1;
}
*bl = fixed_bl;
@ -446,33 +448,3 @@ inflate_huft * FAR *td; /* distance tree result */
*td = fixed_td;
return Z_OK;
}
int inflate_trees_free(t, z)
inflate_huft *t; /* table to free */
z_streamp z; /* for zfree function */
/* Free the malloc'ed tables built by huft_build(), which makes a linked
list of the tables it made, with the links in a dummy first entry of
each table. */
{
register inflate_huft *p, *q, *r;
/* Reverse linked list */
p = Z_NULL;
q = t;
while (q != Z_NULL)
{
r = (q - 1)->next;
(q - 1)->next = p;
p = q;
q = r;
}
/* Go through linked list, freeing from the malloced (t[-1]) address. */
while (p != Z_NULL)
{
q = (--p)->next;
ZFREE(z,p);
p = q;
}
return Z_OK;
}

View File

@ -1,5 +1,5 @@
/* inftrees.h -- header to use inftrees.c
* Copyright (C) 1995-1996 Mark Adler
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@ -27,15 +27,19 @@ struct inflate_huft_s {
} more;
};
#ifdef DEBUG
extern uInt inflate_hufts;
#endif
/* Maximum size of dynamic tree. The maximum found in a long but non-
exhaustive search was 1041 huft structures (875 for length/literals
and 166 for distances, the latter actually the result of an
exhaustive search). The actual maximum is not known, but the
value below is more than safe. */
#define MANY 1440
extern int inflate_trees_bits OF((
uIntf *, /* 19 code lengths */
uIntf *, /* bits tree desired/actual depth */
inflate_huft * FAR *, /* bits tree result */
z_streamp )); /* for zalloc, zfree functions */
inflate_huft *, /* space for trees */
z_streamp)); /* for messages */
extern int inflate_trees_dynamic OF((
uInt, /* number of literal/length codes */
@ -45,15 +49,12 @@ extern int inflate_trees_dynamic OF((
uIntf *, /* distance desired/actual bit depth */
inflate_huft * FAR *, /* literal/length tree result */
inflate_huft * FAR *, /* distance tree result */
z_streamp )); /* for zalloc, zfree functions */
inflate_huft *, /* space for trees */
z_streamp)); /* for messages */
extern int inflate_trees_fixed OF((
uIntf *, /* literal desired/actual bit depth */
uIntf *, /* distance desired/actual bit depth */
inflate_huft * FAR *, /* literal/length tree result */
inflate_huft * FAR *)); /* distance tree result */
extern int inflate_trees_free OF((
inflate_huft *, /* tables to free */
z_streamp )); /* for zfree function */
inflate_huft * FAR *, /* distance tree result */
z_streamp)); /* for memory allocation */

View File

@ -1,5 +1,5 @@
/* inflate_util.c -- data and routines common to blocks and codes
* Copyright (C) 1995-1996 Mark Adler
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/

View File

@ -1,5 +1,5 @@
/* infutil.h -- types and macros common to blocks and codes
* Copyright (C) 1995-1996 Mark Adler
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
@ -41,8 +41,6 @@ struct inflate_blocks_state {
inflate_huft *tb; /* bit length decoding tree */
} trees; /* if DTREE, decoding info for trees */
struct {
inflate_huft *tl;
inflate_huft *td; /* trees to free */
inflate_codes_statef
*codes;
} decode; /* if CODES, current state */
@ -52,6 +50,7 @@ struct inflate_blocks_state {
/* mode independent information */
uInt bitk; /* bits in bit buffer */
uLong bitb; /* bit buffer */
inflate_huft *hufts; /* single malloc for tree space */
Bytef *window; /* sliding window */
Bytef *end; /* one byte after sliding window */
Bytef *read; /* window read pointer */

128
lib/libz/trees.h Normal file
View File

@ -0,0 +1,128 @@
/* header created automatically with -DGEN_TREES_H */
local const ct_data static_ltree[L_CODES+2] = {
{{ 12},{ 8}}, {{140},{ 8}}, {{ 76},{ 8}}, {{204},{ 8}}, {{ 44},{ 8}},
{{172},{ 8}}, {{108},{ 8}}, {{236},{ 8}}, {{ 28},{ 8}}, {{156},{ 8}},
{{ 92},{ 8}}, {{220},{ 8}}, {{ 60},{ 8}}, {{188},{ 8}}, {{124},{ 8}},
{{252},{ 8}}, {{ 2},{ 8}}, {{130},{ 8}}, {{ 66},{ 8}}, {{194},{ 8}},
{{ 34},{ 8}}, {{162},{ 8}}, {{ 98},{ 8}}, {{226},{ 8}}, {{ 18},{ 8}},
{{146},{ 8}}, {{ 82},{ 8}}, {{210},{ 8}}, {{ 50},{ 8}}, {{178},{ 8}},
{{114},{ 8}}, {{242},{ 8}}, {{ 10},{ 8}}, {{138},{ 8}}, {{ 74},{ 8}},
{{202},{ 8}}, {{ 42},{ 8}}, {{170},{ 8}}, {{106},{ 8}}, {{234},{ 8}},
{{ 26},{ 8}}, {{154},{ 8}}, {{ 90},{ 8}}, {{218},{ 8}}, {{ 58},{ 8}},
{{186},{ 8}}, {{122},{ 8}}, {{250},{ 8}}, {{ 6},{ 8}}, {{134},{ 8}},
{{ 70},{ 8}}, {{198},{ 8}}, {{ 38},{ 8}}, {{166},{ 8}}, {{102},{ 8}},
{{230},{ 8}}, {{ 22},{ 8}}, {{150},{ 8}}, {{ 86},{ 8}}, {{214},{ 8}},
{{ 54},{ 8}}, {{182},{ 8}}, {{118},{ 8}}, {{246},{ 8}}, {{ 14},{ 8}},
{{142},{ 8}}, {{ 78},{ 8}}, {{206},{ 8}}, {{ 46},{ 8}}, {{174},{ 8}},
{{110},{ 8}}, {{238},{ 8}}, {{ 30},{ 8}}, {{158},{ 8}}, {{ 94},{ 8}},
{{222},{ 8}}, {{ 62},{ 8}}, {{190},{ 8}}, {{126},{ 8}}, {{254},{ 8}},
{{ 1},{ 8}}, {{129},{ 8}}, {{ 65},{ 8}}, {{193},{ 8}}, {{ 33},{ 8}},
{{161},{ 8}}, {{ 97},{ 8}}, {{225},{ 8}}, {{ 17},{ 8}}, {{145},{ 8}},
{{ 81},{ 8}}, {{209},{ 8}}, {{ 49},{ 8}}, {{177},{ 8}}, {{113},{ 8}},
{{241},{ 8}}, {{ 9},{ 8}}, {{137},{ 8}}, {{ 73},{ 8}}, {{201},{ 8}},
{{ 41},{ 8}}, {{169},{ 8}}, {{105},{ 8}}, {{233},{ 8}}, {{ 25},{ 8}},
{{153},{ 8}}, {{ 89},{ 8}}, {{217},{ 8}}, {{ 57},{ 8}}, {{185},{ 8}},
{{121},{ 8}}, {{249},{ 8}}, {{ 5},{ 8}}, {{133},{ 8}}, {{ 69},{ 8}},
{{197},{ 8}}, {{ 37},{ 8}}, {{165},{ 8}}, {{101},{ 8}}, {{229},{ 8}},
{{ 21},{ 8}}, {{149},{ 8}}, {{ 85},{ 8}}, {{213},{ 8}}, {{ 53},{ 8}},
{{181},{ 8}}, {{117},{ 8}}, {{245},{ 8}}, {{ 13},{ 8}}, {{141},{ 8}},
{{ 77},{ 8}}, {{205},{ 8}}, {{ 45},{ 8}}, {{173},{ 8}}, {{109},{ 8}},
{{237},{ 8}}, {{ 29},{ 8}}, {{157},{ 8}}, {{ 93},{ 8}}, {{221},{ 8}},
{{ 61},{ 8}}, {{189},{ 8}}, {{125},{ 8}}, {{253},{ 8}}, {{ 19},{ 9}},
{{275},{ 9}}, {{147},{ 9}}, {{403},{ 9}}, {{ 83},{ 9}}, {{339},{ 9}},
{{211},{ 9}}, {{467},{ 9}}, {{ 51},{ 9}}, {{307},{ 9}}, {{179},{ 9}},
{{435},{ 9}}, {{115},{ 9}}, {{371},{ 9}}, {{243},{ 9}}, {{499},{ 9}},
{{ 11},{ 9}}, {{267},{ 9}}, {{139},{ 9}}, {{395},{ 9}}, {{ 75},{ 9}},
{{331},{ 9}}, {{203},{ 9}}, {{459},{ 9}}, {{ 43},{ 9}}, {{299},{ 9}},
{{171},{ 9}}, {{427},{ 9}}, {{107},{ 9}}, {{363},{ 9}}, {{235},{ 9}},
{{491},{ 9}}, {{ 27},{ 9}}, {{283},{ 9}}, {{155},{ 9}}, {{411},{ 9}},
{{ 91},{ 9}}, {{347},{ 9}}, {{219},{ 9}}, {{475},{ 9}}, {{ 59},{ 9}},
{{315},{ 9}}, {{187},{ 9}}, {{443},{ 9}}, {{123},{ 9}}, {{379},{ 9}},
{{251},{ 9}}, {{507},{ 9}}, {{ 7},{ 9}}, {{263},{ 9}}, {{135},{ 9}},
{{391},{ 9}}, {{ 71},{ 9}}, {{327},{ 9}}, {{199},{ 9}}, {{455},{ 9}},
{{ 39},{ 9}}, {{295},{ 9}}, {{167},{ 9}}, {{423},{ 9}}, {{103},{ 9}},
{{359},{ 9}}, {{231},{ 9}}, {{487},{ 9}}, {{ 23},{ 9}}, {{279},{ 9}},
{{151},{ 9}}, {{407},{ 9}}, {{ 87},{ 9}}, {{343},{ 9}}, {{215},{ 9}},
{{471},{ 9}}, {{ 55},{ 9}}, {{311},{ 9}}, {{183},{ 9}}, {{439},{ 9}},
{{119},{ 9}}, {{375},{ 9}}, {{247},{ 9}}, {{503},{ 9}}, {{ 15},{ 9}},
{{271},{ 9}}, {{143},{ 9}}, {{399},{ 9}}, {{ 79},{ 9}}, {{335},{ 9}},
{{207},{ 9}}, {{463},{ 9}}, {{ 47},{ 9}}, {{303},{ 9}}, {{175},{ 9}},
{{431},{ 9}}, {{111},{ 9}}, {{367},{ 9}}, {{239},{ 9}}, {{495},{ 9}},
{{ 31},{ 9}}, {{287},{ 9}}, {{159},{ 9}}, {{415},{ 9}}, {{ 95},{ 9}},
{{351},{ 9}}, {{223},{ 9}}, {{479},{ 9}}, {{ 63},{ 9}}, {{319},{ 9}},
{{191},{ 9}}, {{447},{ 9}}, {{127},{ 9}}, {{383},{ 9}}, {{255},{ 9}},
{{511},{ 9}}, {{ 0},{ 7}}, {{ 64},{ 7}}, {{ 32},{ 7}}, {{ 96},{ 7}},
{{ 16},{ 7}}, {{ 80},{ 7}}, {{ 48},{ 7}}, {{112},{ 7}}, {{ 8},{ 7}},
{{ 72},{ 7}}, {{ 40},{ 7}}, {{104},{ 7}}, {{ 24},{ 7}}, {{ 88},{ 7}},
{{ 56},{ 7}}, {{120},{ 7}}, {{ 4},{ 7}}, {{ 68},{ 7}}, {{ 36},{ 7}},
{{100},{ 7}}, {{ 20},{ 7}}, {{ 84},{ 7}}, {{ 52},{ 7}}, {{116},{ 7}},
{{ 3},{ 8}}, {{131},{ 8}}, {{ 67},{ 8}}, {{195},{ 8}}, {{ 35},{ 8}},
{{163},{ 8}}, {{ 99},{ 8}}, {{227},{ 8}}
};
local const ct_data static_dtree[D_CODES] = {
{{ 0},{ 5}}, {{16},{ 5}}, {{ 8},{ 5}}, {{24},{ 5}}, {{ 4},{ 5}},
{{20},{ 5}}, {{12},{ 5}}, {{28},{ 5}}, {{ 2},{ 5}}, {{18},{ 5}},
{{10},{ 5}}, {{26},{ 5}}, {{ 6},{ 5}}, {{22},{ 5}}, {{14},{ 5}},
{{30},{ 5}}, {{ 1},{ 5}}, {{17},{ 5}}, {{ 9},{ 5}}, {{25},{ 5}},
{{ 5},{ 5}}, {{21},{ 5}}, {{13},{ 5}}, {{29},{ 5}}, {{ 3},{ 5}},
{{19},{ 5}}, {{11},{ 5}}, {{27},{ 5}}, {{ 7},{ 5}}, {{23},{ 5}}
};
const uch _dist_code[DIST_CODE_LEN] = {
0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8,
8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10,
10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13,
13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15,
15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0, 0, 16, 17,
18, 18, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 22, 22,
23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27,
27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
27, 27, 27, 27, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
28, 28, 28, 28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29
};
const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {
0, 1, 2, 3, 4, 5, 6, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12, 12,
13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16, 16,
17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19,
19, 19, 19, 19, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20,
21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22,
22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, 23, 23, 23, 23,
23, 23, 23, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 26, 26, 26,
26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
26, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 28
};
local const int base_length[LENGTH_CODES] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56,
64, 80, 96, 112, 128, 160, 192, 224, 0
};
local const int base_dist[D_CODES] = {
0, 1, 2, 3, 4, 6, 8, 12, 16, 24,
32, 48, 64, 96, 128, 192, 256, 384, 512, 768,
1024, 1536, 2048, 3072, 4096, 6144, 8192, 12288, 16384, 24576
};

107
lib/libz/zlib.3 Normal file
View File

@ -0,0 +1,107 @@
.TH ZLIB 3 "27 February 1998"
.SH NAME
zlib \- compression/decompression library
.SH SYNOPSIS
[see
.I zlib.h
for full description]
.SH DESCRIPTION
The
.I zlib
library is a general purpose data compression library.
The code is thread safe.
It 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.
.LP
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.
.LP
The library also supports reading and writing files in
.I gzip
(.gz) format
with an interface similar to that of stdio.
.LP
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.
.LP
All functions of the compression library are documented in the file
.IR zlib.h.
The distribution source includes examples of use of the library
the files
.I example.c
and
.IR minigzip.c .
.LP
A Java implementation of
.IR zlib
is available in the Java Development Kit 1.1
.IP
http://www.javasoft.com/products/JDK/1.1/docs/api/Package-java.util.zip.html
.LP
A Perl interface to
.IR zlib ,
written by Paul Marquess (pmarquess@bfsec.bt.co.uk)
is available at CPAN (Comprehensive Perl Archive Network) sites,
such as:
.IP
ftp://ftp.cis.ufl.edu/pub/perl/CPAN/modules/by-module/Compress/Compress-Zlib*
.LP
A Python interface to
.IR zlib
written by A.M. Kuchling <amk@magnet.com>
is available from the Python Software Association sites, such as:
.IP
ftp://ftp.python.org/pub/python/contrib/Encoding/zlib*.tar.gz
.SH "SEE ALSO"
Questions about zlib should be sent to:
.IP
zlib@quest.jpl.nasa.gov
or, if this fails, to the author addresses given below.
The zlib home page is:
.IP
http://www.cdrom.com/pub/infozip/zlib/
.LP
The data format used by the zlib library is described by RFC
(Request for Comments) 1950 to 1952 in the files:
.IP
ftp://ds.internic.net/rfc/rfc1950.txt (zlib format)
.br
rfc1951.txt (deflate format)
.br
rfc1952.txt (gzip format)
.LP
These documents are also available in other formats from:
.IP
ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html
.SH AUTHORS
Version 1.1.1
Copyright (C) 1995-1998 Jean-loup Gailly (jloup@gzip.org)
and Mark Adler (madler@alumni.caltech.edu).
.LP
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.
See the distribution directory with respect to requirements
governing redistribution.
The deflate format used by
.I zlib
was defined by Phil Katz.
The deflate and
.I zlib
specifications were written by Peter Deutsch.
Thanks to all the people who reported problems and suggested various
improvements in
.IR zlib ;
who are too numerous to cite here.
.LP
UNIX manual page by R. P. C. Rodgers,
U.S. National Library of Medicine (rodgers@nlm.nih.gov).
.\" end of man page

View File

@ -1,7 +1,7 @@
/* zlib.h -- interface of the 'zlib' general purpose compression library
version 1.0.4, Jul 24th, 1996.
version 1.1.1, Feb 27th, 1998
Copyright (C) 1995-1996 Jean-loup Gailly and Mark Adler
Copyright (C) 1995-1998 Jean-loup Gailly and Mark Adler
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
@ -20,7 +20,7 @@
3. This notice may not be removed or altered from any source distribution.
Jean-loup Gailly Mark Adler
gzip@prep.ai.mit.edu madler@alumni.caltech.edu
jloup@gzip.org madler@alumni.caltech.edu
The data format used by the zlib library is described by RFCs (Request for
@ -37,30 +37,27 @@ extern "C" {
#include "zconf.h"
#define ZLIB_VERSION "1.0.4"
#define ZLIB_VERSION "1.1.1"
/*
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 may be added later and will have the same
(deflation) but other algorithms will be added later and will have the same
stream interface.
For compression the application must provide the output buffer and
may optionally provide the input buffer for optimization. For decompression,
the application must provide the input buffer and may optionally provide
the output buffer for optimization.
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 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.
The library also supports reading and writing files in gzip (.gz) format
with an interface similar to that of stdio.
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));
@ -104,6 +101,9 @@ typedef z_stream FAR *z_streamp;
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,
@ -123,7 +123,7 @@ typedef z_stream FAR *z_streamp;
/* constants */
#define Z_NO_FLUSH 0
#define Z_PARTIAL_FLUSH 1
#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
@ -168,7 +168,7 @@ typedef z_stream FAR *z_streamp;
/* basic functions */
extern const char * EXPORT zlibVersion OF((void));
extern 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.
@ -176,7 +176,7 @@ extern const char * EXPORT zlibVersion OF((void));
*/
/*
extern int EXPORT deflateInit OF((z_streamp strm, int level));
extern 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.
@ -198,9 +198,15 @@ extern int EXPORT deflateInit OF((z_streamp strm, int level));
*/
extern int EXPORT deflate OF((z_streamp strm, int flush));
extern int ZEXPORT deflate OF((z_streamp strm, int flush));
/*
Performs one or both of the following actions:
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
@ -222,24 +228,23 @@ extern int EXPORT 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.
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
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.
Z_SYNC_FLUSH has the same effect as partial flush except that the compressed
output is byte aligned (the compressor can clear its internal bit buffer)
and the current block is always terminated; this can be useful if the
compressor has to be restarted from scratch after an interruption (in which
case the internal state of the compressor may be lost).
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 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).
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
the 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).
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
@ -254,6 +259,9 @@ extern int EXPORT deflate OF((z_streamp strm, int flush));
0.1% larger than avail_in plus 12 bytes. 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 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
@ -267,7 +275,7 @@ extern int EXPORT deflate OF((z_streamp strm, int flush));
*/
extern int EXPORT deflateEnd OF((z_streamp strm));
extern 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
@ -282,24 +290,35 @@ extern int EXPORT deflateEnd OF((z_streamp strm));
/*
extern int EXPORT inflateInit OF((z_streamp strm));
extern int ZEXPORT inflateInit OF((z_streamp 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.
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: this will be
done by inflate().
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.)
*/
extern int EXPORT inflate OF((z_streamp strm, int flush));
extern int ZEXPORT inflate OF((z_streamp strm, int flush));
/*
Performs one or both of the following actions:
inflate decompresses as much data as possible, and stops when the input
buffer becomes empty or the output buffer becomes full. It may some
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
@ -320,9 +339,9 @@ extern int EXPORT inflate OF((z_streamp strm, int flush));
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
If the parameter flush is set to Z_SYNC_FLUSH, inflate flushes as much
output as possible to the output buffer. The flushing behavior of inflate is
not specified for values of the flush parameter other than Z_PARTIAL_FLUSH
not specified for values of the flush parameter other than Z_SYNC_FLUSH
and Z_FINISH, but the current implementation actually flushes as much output
as possible anyway.
@ -337,22 +356,30 @@ extern int EXPORT inflate OF((z_streamp strm, int flush));
is never required, but can be used to inform inflate that a faster routine
may be used for the single inflate() call.
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 (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.
If a preset dictionary is needed at this point (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() 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
adler32 checksum), 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.
*/
extern int EXPORT inflateEnd OF((z_streamp strm));
extern 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
@ -370,26 +397,25 @@ extern int EXPORT inflateEnd OF((z_streamp strm));
*/
/*
extern int EXPORT deflateInit2 OF((z_streamp strm,
int level,
int method,
int windowBits,
int memLevel,
int strategy));
extern 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. (Method 9 will allow a 64K history buffer and
partial block flushes.)
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 (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.
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.
The memLevel parameter specifies how much memory should be allocated
for the internal compression state. memLevel=1 uses minimum memory but
@ -408,42 +434,35 @@ extern int EXPORT deflateInit2 OF((z_streamp strm,
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
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().
If the history buffer is provided by the application, next_in must
must never be changed by the application since the compressor maintains
information inside this buffer from call to call; the application
must provide more input only by increasing avail_in. next_in is always
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 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().
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().
*/
extern int EXPORT deflateSetDictionary OF((z_streamp strm,
const Bytef *dictionary,
uInt dictLength));
extern int ZEXPORT deflateSetDictionary OF((z_streamp 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
Initializes the compression dictionary 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.
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.
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
@ -451,21 +470,16 @@ extern int EXPORT deflateSetDictionary OF((z_streamp strm,
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().
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().
*/
extern int EXPORT deflateCopy OF((z_streamp dest,
z_streamp source));
extern int ZEXPORT deflateCopy OF((z_streamp dest,
z_streamp source));
/*
Sets the destination stream as a complete copy of the source stream. If
the source stream is using an application-supplied history buffer, a new
buffer is allocated for the destination stream. The compressed output
buffer is always application-supplied. It's the responsibility of the
application to provide the correct values of next_out and avail_out for the
next call of deflate.
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
@ -480,7 +494,7 @@ extern int EXPORT deflateCopy OF((z_streamp dest,
destination.
*/
extern int EXPORT deflateReset OF((z_streamp strm));
extern 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.
@ -491,14 +505,15 @@ extern int EXPORT deflateReset OF((z_streamp strm));
stream state was inconsistent (such as zalloc or state being NULL).
*/
extern int EXPORT deflateParams OF((z_streamp strm, int level, int strategy));
extern int ZEXPORT deflateParams OF((z_streamp strm, int level, int strategy));
/*
Dynamically update the compression level and compression strategy.
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().
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
@ -510,49 +525,37 @@ extern int EXPORT deflateParams OF((z_streamp strm, int level, int strategy));
*/
/*
extern int EXPORT inflateInit2 OF((z_streamp strm,
int windowBits));
extern int ZEXPORT inflateInit2 OF((z_streamp 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.
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 value 16 will be allowed soon). The
default value is 15 if inflateInit is used instead. 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.
this version of the library. The default value is 15 if inflateInit is used
instead. 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.
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 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().
If the history buffer is provided by the application, next_out must
never be changed by the application since the decompressor maintains
history information inside this buffer from call to call; the application
can only reset next_out to the beginning of the history buffer when
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 a parameter is invalid (such as
windowBits < 8). msg is set to null if there is no error message.
inflateInit2 does not perform any decompression: this will be done by
inflate().
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 negative
memLevel). 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.)
*/
extern int EXPORT inflateSetDictionary OF((z_streamp strm,
const Bytef *dictionary,
uInt dictLength));
extern int ZEXPORT inflateSetDictionary OF((z_streamp 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
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).
inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
@ -563,14 +566,14 @@ extern int EXPORT inflateSetDictionary OF((z_streamp strm,
inflate().
*/
extern int EXPORT inflateSync OF((z_streamp strm));
extern int ZEXPORT inflateSync OF((z_streamp strm));
/*
Skips invalid compressed data until the special marker (see deflate()
above) can be found, or until all available input is skipped. No output
is provided.
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 the special marker has been found, Z_BUF_ERROR
if no more input was provided, Z_DATA_ERROR if no marker has been found,
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
@ -578,7 +581,7 @@ extern int EXPORT inflateSync OF((z_streamp strm));
until success or end of the input data.
*/
extern int EXPORT inflateReset OF((z_streamp strm));
extern 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.
@ -594,13 +597,13 @@ extern int EXPORT inflateReset OF((z_streamp strm));
/*
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, window size,
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.
*/
extern int EXPORT compress OF((Bytef *dest, uLongf *destLen,
const Bytef *source, uLong sourceLen));
extern 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
@ -614,8 +617,23 @@ extern int EXPORT compress OF((Bytef *dest, uLongf *destLen,
buffer.
*/
extern int EXPORT uncompress OF((Bytef *dest, uLongf *destLen,
const Bytef *source, uLong sourceLen));
extern 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 0.1% larger than sourceLen plus
12 bytes. 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.
*/
extern 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
@ -635,19 +653,23 @@ extern int EXPORT uncompress OF((Bytef *dest, uLongf *destLen,
typedef voidp gzFile;
extern gzFile EXPORT gzopen OF((const char *path, const char *mode));
extern 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"). 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.
("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for
Huffman only compression as in "wb1h". (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).
*/
zlib error is Z_MEM_ERROR). */
extern gzFile EXPORT gzdopen OF((int fd, const char *mode));
extern 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
@ -660,7 +682,15 @@ extern gzFile EXPORT gzdopen OF((int fd, const char *mode));
the (de)compression state.
*/
extern int EXPORT gzread OF((gzFile file, voidp buf, unsigned len));
extern 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.
*/
extern 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
@ -668,14 +698,49 @@ extern int EXPORT 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 EXPORT gzwrite OF((gzFile file, const voidp buf, unsigned len));
extern int ZEXPORT 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
(0 in case of error).
*/
extern int EXPORT gzflush OF((gzFile file, int flush));
extern 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).
*/
extern 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.
*/
extern 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.
*/
extern 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.
*/
extern 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.
*/
extern 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
@ -685,14 +750,53 @@ extern int EXPORT gzflush OF((gzFile file, int flush));
degrade compression.
*/
extern int EXPORT gzclose OF((gzFile file));
extern 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.
*/
extern 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)
*/
extern 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)
*/
extern int ZEXPORT gzeof OF((gzFile file));
/*
Returns 1 when EOF has previously been detected reading the given
input stream, otherwise zero.
*/
extern 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).
*/
extern const char * EXPORT gzerror OF((gzFile file, int *errnum));
extern 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
@ -709,7 +813,7 @@ extern const char * EXPORT gzerror OF((gzFile file, int *errnum));
compression library.
*/
extern uLong EXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
extern 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
@ -726,7 +830,7 @@ extern uLong EXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
if (adler != original_adler) error();
*/
extern uLong EXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
extern 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
@ -748,30 +852,34 @@ extern uLong EXPORT crc32 OF((uLong crc, const Bytef *buf, uInt len));
/* deflateInit and inflateInit are macros to allow checking the zlib version
* and the compiler's view of z_stream:
*/
extern int EXPORT deflateInit_ OF((z_streamp strm, int level,
const char *version, int stream_size));
extern int EXPORT inflateInit_ OF((z_streamp strm,
const char *version, int stream_size));
extern int EXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
int windowBits, int memLevel, int strategy,
const char *version, int stream_size));
extern int EXPORT inflateInit2_ OF((z_streamp strm, int windowBits,
const char *version, int stream_size));
extern int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
const char *version, int stream_size));
extern int ZEXPORT inflateInit_ OF((z_streamp strm,
const char *version, int stream_size));
extern int ZEXPORT deflateInit2_ OF((z_streamp strm, int level, int method,
int windowBits, int memLevel,
int strategy, const char *version,
int stream_size));
extern int ZEXPORT inflateInit2_ OF((z_streamp 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))
(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() */
extern const char * ZEXPORT zError OF((int err));
extern int ZEXPORT inflateSyncPoint OF((z_streamp z));
extern const uLongf * ZEXPORT get_crc_table OF((void));
#ifdef __cplusplus
}