提交 4f3865fb 编写于 作者: R Richard Purdie 提交者: Linus Torvalds

[PATCH] zlib_inflate: Upgrade library code to a recent version

Upgrade the zlib_inflate implementation in the kernel from a patched
version 1.1.3/4 to a patched 1.2.3.

The code in the kernel is about seven years old and I noticed that the
external zlib library's inflate performance was significantly faster (~50%)
than the code in the kernel on ARM (and faster again on x86_32).

For comparison the newer deflate code is 20% slower on ARM and 50% slower
on x86_32 but gives an approx 1% compression ratio improvement.  I don't
consider this to be an improvement for kernel use so have no plans to
change the zlib_deflate code.

Various changes have been made to the zlib code in the kernel, the most
significant being the extra functions/flush option used by ppp_deflate.
This update reimplements the features PPP needs to ensure it continues to
work.

This code has been tested on ARM under both JFFS2 (with zlib compression
enabled) and ppp_deflate and on x86_32.  JFFS2 sees an approx.  10% real
world file read speed improvement.

This patch also removes ZLIB_VERSION as it no longer has a correct value.
We don't need version checks anyway as the kernel's module handling will
take care of that for us.  This removal is also more in keeping with the
zlib author's wishes (http://www.zlib.net/zlib_faq.html#faq24) and I've
added something to the zlib.h header to note its a modified version.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Acked-by: NJoern Engel <joern@wh.fh-wedel.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
上级 4f1bcaf0
......@@ -29,8 +29,8 @@ OBJCOPYFLAGS := contents,alloc,load,readonly,data
OBJCOPY_COFF_ARGS := -O aixcoff-rs6000 --set-start 0x500000
OBJCOPY_MIB_ARGS := -O aixcoff-rs6000 -R .stab -R .stabstr -R .comment
zlib := infblock.c infcodes.c inffast.c inflate.c inftrees.c infutil.c
zlibheader := infblock.h infcodes.h inffast.h inftrees.h infutil.h
zlib := inffast.c inflate.c inftrees.c
zlibheader := inffast.h inffixed.h inflate.h inftrees.h infutil.h
zliblinuxheader := zlib.h zconf.h zutil.h
$(addprefix $(obj)/,$(zlib) main.o): $(addprefix $(obj)/,$(zliblinuxheader)) $(addprefix $(obj)/,$(zlibheader))
......
......@@ -5,7 +5,7 @@
CFLAGS_kbd.o := -Idrivers/char
CFLAGS_vreset.o := -Iarch/ppc/boot/include
zlib := infblock.c infcodes.c inffast.c inflate.c inftrees.c infutil.c
zlib := inffast.c inflate.c inftrees.c
lib-y += $(zlib:.c=.o) div64.o
lib-$(CONFIG_VGA_CONSOLE) += vreset.o kbd.o
......
......@@ -2,7 +2,7 @@
# Makefile for some libs needed by zImage.
#
zlib := infblock.c infcodes.c inffast.c inflate.c inftrees.c infutil.c
zlib := inffast.c inflate.c inftrees.c
lib-y += $(zlib:.c=.o) zmem.o
......
......@@ -33,6 +33,18 @@
*/
#ifndef MAX_WBITS
# define MAX_WBITS 15 /* 32K LZ77 window */
#endif
/* default windowBits for decompression. MAX_WBITS is for compression only */
#ifndef DEF_WBITS
# define DEF_WBITS MAX_WBITS
#endif
/* default memLevel */
#if MAX_MEM_LEVEL >= 8
# define DEF_MEM_LEVEL 8
#else
# define DEF_MEM_LEVEL MAX_MEM_LEVEL
#endif
/* Type declarations */
......
/* zlib.h -- interface of the 'zlib' general purpose compression library
version 1.1.3, July 9th, 1998
Copyright (C) 1995-1998 Jean-loup Gailly and Mark Adler
Copyright (C) 1995-2005 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
......@@ -24,7 +23,7 @@
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
Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
(zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format).
*/
......@@ -33,7 +32,22 @@
#include <linux/zconf.h>
#define ZLIB_VERSION "1.1.3"
/* zlib deflate based on ZLIB_VERSION "1.1.3" */
/* zlib inflate based on ZLIB_VERSION "1.2.3" */
/*
This is a modified version of zlib for use inside the Linux kernel.
The main changes are to perform all memory allocation in advance.
Inflation Changes:
* Z_PACKET_FLUSH is added and used by ppp_deflate. Before returning
this checks there is no more input data available and the next data
is a STORED block. It also resets the mode to be read for the next
data, all as per PPP requirements.
* Addition of zlib_inflateIncomp which copies incompressible data into
the history window and adjusts the accoutning without calling
zlib_inflate itself to inflate the data.
*/
/*
The 'zlib' compression library provides in-memory compression and
......@@ -48,9 +62,18 @@
application must provide more input and/or consume the output
(providing more output space) before each call.
The compressed data format used by default by the in-memory functions is
the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
around a deflate stream, which is itself documented in RFC 1951.
The library also supports reading and writing files in gzip (.gz) format
with an interface similar to that of stdio.
The zlib format was designed to be compact and fast for use in memory
and on communications channels. The gzip format was designed for single-
file compression on file systems, has a larger header than zlib to maintain
directory information, and uses a different, slower check method than zlib.
The library does not install any signal handler. The decoder checks
the consistency of the compressed data, so the library should never
crash even in case of corrupted input.
......@@ -119,7 +142,8 @@ typedef z_stream *z_streamp;
#define Z_SYNC_FLUSH 3
#define Z_FULL_FLUSH 4
#define Z_FINISH 5
/* Allowed flush values; see deflate() below for details */
#define Z_BLOCK 6 /* Only for inflate at present */
/* Allowed flush values; see deflate() and inflate() below for details */
#define Z_OK 0
#define Z_STREAM_END 1
......@@ -155,13 +179,6 @@ typedef z_stream *z_streamp;
/* basic functions */
extern const char * zlib_zlibVersion (void);
/* The application can compare zlibVersion and ZLIB_VERSION for consistency.
If the first character differs, the library code actually used is
not compatible with the zlib.h header file used by the application.
This check is automatically made by deflateInit and inflateInit.
*/
extern int zlib_deflate_workspacesize (void);
/*
Returns the number of bytes that needs to be allocated for a per-
......@@ -315,9 +332,9 @@ extern int zlib_inflateInit (z_streamp strm);
extern int zlib_inflate (z_streamp strm, int flush);
/*
inflate decompresses as much data as possible, and stops when the input
buffer becomes empty or the output buffer becomes full. It may some
introduce some output latency (reading input without producing any output)
except when forced to flush.
buffer becomes empty or the output buffer becomes full. It may introduce
some output latency (reading input without producing any output) except when
forced to flush.
The detailed semantics are as follows. inflate performs one or both of the
following actions:
......@@ -341,11 +358,26 @@ extern int zlib_inflate (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_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_SYNC_FLUSH
and Z_FINISH, but the current implementation actually flushes as much output
as possible anyway.
The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH,
Z_FINISH, or Z_BLOCK. Z_SYNC_FLUSH requests that inflate() flush as much
output as possible to the output buffer. Z_BLOCK requests that inflate() stop
if and when it gets to the next deflate block boundary. When decoding the
zlib or gzip format, this will cause inflate() to return immediately after
the header and before the first block. When doing a raw inflate, inflate()
will go ahead and process the first block, and will return when it gets to
the end of that block, or when it runs out of data.
The Z_BLOCK option assists in appending to or combining deflate streams.
Also to assist in this, on return inflate() will set strm->data_type to the
number of unused bits in the last byte taken from strm->next_in, plus 64
if inflate() is currently decoding the last block in the deflate stream,
plus 128 if inflate() returned immediately after decoding an end-of-block
code or decoding the complete header up to just before the first byte of the
deflate stream. The end-of-block will not be indicated until all of the
uncompressed data from that block has been written to strm->next_out. The
number of unused bits may in general be greater than seven, except when
bit 7 of data_type is set, in which case the number of unused bits will be
less than eight.
inflate() should normally be called until it returns Z_STREAM_END or an
error. However if all decompression is to be performed in a single step
......@@ -355,29 +387,44 @@ extern int zlib_inflate (z_streamp strm, int flush);
uncompressed data. (The size of the uncompressed data may have been saved
by the compressor for this purpose.) The next operation on this stream must
be inflateEnd to deallocate the decompression state. The use of Z_FINISH
is never required, but can be used to inform inflate that a faster routine
is never required, but can be used to inform inflate that a faster approach
may be used for the single inflate() call.
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.
In this implementation, inflate() always flushes as much output as
possible to the output buffer, and always uses the faster approach on the
first call. So the only effect of the flush parameter in this implementation
is on the return value of inflate(), as noted below, or when it returns early
because Z_BLOCK is used.
If a preset dictionary is needed after this call (see inflateSetDictionary
below), inflate sets strm->adler to the adler32 checksum of the dictionary
chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
strm->adler to the adler32 checksum of all output produced so far (that is,
total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
below. At the end of the stream, inflate() checks that its computed adler32
checksum is equal to that saved by the compressor and returns Z_STREAM_END
only if the checksum is correct.
inflate() will decompress and check either zlib-wrapped or gzip-wrapped
deflate data. The header type is detected automatically. Any information
contained in the gzip header is not retained, so applications that need that
information should instead use raw inflate, see inflateInit2() below, or
inflateBack() and perform their own processing of the gzip header and
trailer.
inflate() returns Z_OK if some progress has been made (more input processed
or more output produced), Z_STREAM_END if the end of the compressed data has
been reached and all uncompressed output has been produced, Z_NEED_DICT if a
preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
corrupted (input stream not conforming to the zlib format or incorrect
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.
corrupted (input stream not conforming to the zlib format or incorrect check
value), Z_STREAM_ERROR if the stream structure was inconsistent (for example
if next_in or next_out was NULL), Z_MEM_ERROR if there was not enough memory,
Z_BUF_ERROR if no progress is possible or if there was not enough room in the
output buffer when Z_FINISH is used. Note that Z_BUF_ERROR is not fatal, and
inflate() can be called again with more input and more output space to
continue decompressing. If Z_DATA_ERROR is returned, the application may then
call inflateSync() to look for a good compression block if a partial recovery
of the data is desired.
*/
......@@ -547,16 +594,36 @@ extern int inflateInit2 (z_streamp strm, int windowBits);
The windowBits parameter is the base two logarithm of the maximum window
size (the size of the history buffer). It should be in the range 8..15 for
this version of the library. The default value is 15 if inflateInit is used
instead. 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.
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.)
instead. windowBits must be greater than or equal to the windowBits value
provided to deflateInit2() while compressing, or it must be equal to 15 if
deflateInit2() was not used. If a compressed stream with a larger window
size is given as input, inflate() will return with the error code
Z_DATA_ERROR instead of trying to allocate a larger window.
windowBits can also be -8..-15 for raw inflate. In this case, -windowBits
determines the window size. inflate() will then process raw deflate data,
not looking for a zlib or gzip header, not generating a check value, and not
looking for any check values for comparison at the end of the stream. This
is for use with other formats that use the deflate compressed data format
such as zip. Those formats provide their own check values. If a custom
format is developed using the raw deflate format for compressed data, it is
recommended that a check value such as an adler32 or a crc32 be applied to
the uncompressed data as is done in the zlib, gzip, and zip formats. For
most applications, the zlib format should be used as is. Note that comments
above on the use in deflateInit2() applies to the magnitude of windowBits.
windowBits can also be greater than 15 for optional gzip decoding. Add
32 to windowBits to enable zlib and gzip decoding with automatic header
detection, or add 16 to decode only the gzip format (the zlib format will
return a Z_DATA_ERROR). If a gzip stream is being decoded, strm->adler is
a crc32 instead of an adler32.
inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
memory, Z_STREAM_ERROR if a parameter is invalid (such as a null strm). msg
is set to null if there is no error message. inflateInit2 does not perform
any decompression apart from reading the zlib header if present: this will
be done by inflate(). (So next_in and avail_in may be modified, but next_out
and avail_out are unchanged.)
*/
extern int zlib_inflateSetDictionary (z_streamp strm,
......@@ -564,16 +631,19 @@ extern int zlib_inflateSetDictionary (z_streamp strm,
uInt dictLength);
/*
Initializes the decompression dictionary from the given uncompressed byte
sequence. This function must be called immediately after a call of inflate
if this call returned Z_NEED_DICT. The dictionary chosen by the compressor
can be determined from the Adler32 value returned by this call of
inflate. The compressor and decompressor must use exactly the same
dictionary (see deflateSetDictionary).
sequence. This function must be called immediately after a call of inflate,
if that call returned Z_NEED_DICT. The dictionary chosen by the compressor
can be determined from the adler32 value returned by that call of inflate.
The compressor and decompressor must use exactly the same dictionary (see
deflateSetDictionary). For raw inflate, this function can be called
immediately after inflateInit2() or inflateReset() and before any call of
inflate() to set the dictionary. The application must insure that the
dictionary that was used for compression is provided.
inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
parameter is invalid (such as NULL dictionary) or the stream state is
inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
expected one (incorrect Adler32 value). inflateSetDictionary does not
expected one (incorrect adler32 value). inflateSetDictionary does not
perform any decompression: this will be done by subsequent calls of
inflate().
*/
......@@ -614,40 +684,19 @@ extern int zlib_inflateIncomp (z_stream *strm);
containing the data at next_in (except that the data is not output).
*/
/* various hacks, don't look :) */
/* deflateInit and inflateInit are macros to allow checking the zlib version
* and the compiler's view of z_stream:
*/
extern int zlib_deflateInit_ (z_streamp strm, int level,
const char *version, int stream_size);
extern int zlib_inflateInit_ (z_streamp strm,
const char *version, int stream_size);
extern int zlib_deflateInit2_ (z_streamp strm, int level, int method,
int windowBits, int memLevel,
int strategy, const char *version,
int stream_size);
extern int zlib_inflateInit2_ (z_streamp strm, int windowBits,
const char *version, int stream_size);
#define zlib_deflateInit(strm, level) \
zlib_deflateInit_((strm), (level), ZLIB_VERSION, sizeof(z_stream))
zlib_deflateInit2((strm), (level), Z_DEFLATED, MAX_WBITS, \
DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY)
#define zlib_inflateInit(strm) \
zlib_inflateInit_((strm), ZLIB_VERSION, sizeof(z_stream))
#define zlib_deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
zlib_deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
(strategy), ZLIB_VERSION, sizeof(z_stream))
#define zlib_inflateInit2(strm, windowBits) \
zlib_inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
zlib_inflateInit2((strm), DEF_WBITS)
extern int zlib_deflateInit2(z_streamp strm, int level, int method,
int windowBits, int memLevel,
int strategy);
extern int zlib_inflateInit2(z_streamp strm, int windowBits);
#if !defined(_Z_UTIL_H) && !defined(NO_DUMMY_DECL)
struct internal_state {int dummy;}; /* hack for buggy compilers */
#endif
extern const char * zlib_zError (int err);
#if 0
extern int zlib_inflateSyncPoint (z_streamp z);
#endif
extern const uLong * zlib_get_crc_table (void);
#endif /* _ZLIB_H */
......@@ -23,18 +23,6 @@ typedef unsigned long ulg;
/* common constants */
#ifndef DEF_WBITS
# define DEF_WBITS MAX_WBITS
#endif
/* default windowBits for decompression. MAX_WBITS is for compression only */
#if MAX_MEM_LEVEL >= 8
# define DEF_MEM_LEVEL 8
#else
# define DEF_MEM_LEVEL MAX_MEM_LEVEL
#endif
/* default memLevel */
#define STORED_BLOCK 0
#define STATIC_TREES 1
#define DYN_TREES 2
......
......@@ -164,34 +164,17 @@ static const config configuration_table[10] = {
memset((char *)s->head, 0, (unsigned)(s->hash_size-1)*sizeof(*s->head));
/* ========================================================================= */
int zlib_deflateInit_(
z_streamp strm,
int level,
const char *version,
int stream_size
)
{
return zlib_deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS,
DEF_MEM_LEVEL,
Z_DEFAULT_STRATEGY, version, stream_size);
/* To do: ignore strm->next_in if we use it as window */
}
/* ========================================================================= */
int zlib_deflateInit2_(
int zlib_deflateInit2(
z_streamp strm,
int level,
int method,
int windowBits,
int memLevel,
int strategy,
const char *version,
int stream_size
int strategy
)
{
deflate_state *s;
int noheader = 0;
static char* my_version = ZLIB_VERSION;
deflate_workspace *mem;
ush *overlay;
......@@ -199,10 +182,6 @@ int zlib_deflateInit2_(
* output size for (length,distance) codes is <= 24 bits.
*/
if (version == NULL || version[0] != my_version[0] ||
stream_size != sizeof(z_stream)) {
return Z_VERSION_ERROR;
}
if (strm == NULL) return Z_STREAM_ERROR;
strm->msg = NULL;
......
......@@ -12,8 +12,7 @@
EXPORT_SYMBOL(zlib_deflate_workspacesize);
EXPORT_SYMBOL(zlib_deflate);
EXPORT_SYMBOL(zlib_deflateInit_);
EXPORT_SYMBOL(zlib_deflateInit2_);
EXPORT_SYMBOL(zlib_deflateInit2);
EXPORT_SYMBOL(zlib_deflateEnd);
EXPORT_SYMBOL(zlib_deflateReset);
MODULE_LICENSE("GPL");
......@@ -15,5 +15,5 @@
obj-$(CONFIG_ZLIB_INFLATE) += zlib_inflate.o
zlib_inflate-objs := infblock.o infcodes.o inffast.o inflate.o \
inflate_sync.o inftrees.o infutil.o inflate_syms.o
zlib_inflate-objs := inffast.o inflate.o \
inftrees.o inflate_syms.o
/* infblock.c -- interpret and process block types to last block
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include <linux/zutil.h>
#include "infblock.h"
#include "inftrees.h"
#include "infcodes.h"
#include "infutil.h"
struct inflate_codes_state;
/* simplify the use of the inflate_huft type with some defines */
#define exop word.what.Exop
#define bits word.what.Bits
/* Table for deflate from PKZIP's appnote.txt. */
static const uInt border[] = { /* Order of the bit length code lengths */
16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
/*
Notes beyond the 1.93a appnote.txt:
1. Distance pointers never point before the beginning of the output
stream.
2. Distance pointers can point back across blocks, up to 32k away.
3. There is an implied maximum of 7 bits for the bit length table and
15 bits for the actual data.
4. If only one code exists, then it is encoded using one bit. (Zero
would be more efficient, but perhaps a little confusing.) If two
codes exist, they are coded using one bit each (0 and 1).
5. There is no way of sending zero distance codes--a dummy must be
sent if there are none. (History: a pre 2.0 version of PKZIP would
store blocks with no distance codes, but this was discovered to be
too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
zero distance codes, which is sent as one code of zero bits in
length.
6. There are up to 286 literal/length codes. Code 256 represents the
end-of-block. Note however that the static length tree defines
288 codes just to fill out the Huffman codes. Codes 286 and 287
cannot be used though, since there is no length base or extra bits
defined for them. Similarily, there are up to 30 distance codes.
However, static trees define 32 codes (all 5 bits) to fill out the
Huffman codes, but the last two had better not show up in the data.
7. Unzip can check dynamic Huffman blocks for complete code sets.
The exception is that a single code would not be complete (see #4).
8. The five bits following the block type is really the number of
literal codes sent minus 257.
9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
(1+6+6). Therefore, to output three times the length, you output
three codes (1+1+1), whereas to output four times the same length,
you only need two codes (1+3). Hmm.
10. In the tree reconstruction algorithm, Code = Code + Increment
only if BitLength(i) is not zero. (Pretty obvious.)
11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
12. Note: length code 284 can represent 227-258, but length code 285
really is 258. The last length deserves its own, short code
since it gets used a lot in very redundant files. The length
258 is special since 258 - 3 (the min match length) is 255.
13. The literal/length and distance code bit lengths are read as a
single stream of lengths. It is possible (and advantageous) for
a repeat code (16, 17, or 18) to go across the boundary between
the two sets of lengths.
*/
void zlib_inflate_blocks_reset(
inflate_blocks_statef *s,
z_streamp z,
uLong *c
)
{
if (c != NULL)
*c = s->check;
if (s->mode == CODES)
zlib_inflate_codes_free(s->sub.decode.codes, z);
s->mode = TYPE;
s->bitk = 0;
s->bitb = 0;
s->read = s->write = s->window;
if (s->checkfn != NULL)
z->adler = s->check = (*s->checkfn)(0L, NULL, 0);
}
inflate_blocks_statef *zlib_inflate_blocks_new(
z_streamp z,
check_func c,
uInt w
)
{
inflate_blocks_statef *s;
s = &WS(z)->working_blocks_state;
s->hufts = WS(z)->working_hufts;
s->window = WS(z)->working_window;
s->end = s->window + w;
s->checkfn = c;
s->mode = TYPE;
zlib_inflate_blocks_reset(s, z, NULL);
return s;
}
int zlib_inflate_blocks(
inflate_blocks_statef *s,
z_streamp z,
int r
)
{
uInt t; /* temporary storage */
uLong b; /* bit buffer */
uInt k; /* bits in bit buffer */
Byte *p; /* input data pointer */
uInt n; /* bytes available there */
Byte *q; /* output window write pointer */
uInt m; /* bytes to end of window or read pointer */
/* copy input/output information to locals (UPDATE macro restores) */
LOAD
/* process input based on current state */
while (1) switch (s->mode)
{
case TYPE:
NEEDBITS(3)
t = (uInt)b & 7;
s->last = t & 1;
switch (t >> 1)
{
case 0: /* stored */
DUMPBITS(3)
t = k & 7; /* go to byte boundary */
DUMPBITS(t)
s->mode = LENS; /* get length of stored block */
break;
case 1: /* fixed */
{
uInt bl, bd;
inflate_huft *tl, *td;
zlib_inflate_trees_fixed(&bl, &bd, &tl, &td, s->hufts, z);
s->sub.decode.codes = zlib_inflate_codes_new(bl, bd, tl, td, z);
if (s->sub.decode.codes == NULL)
{
r = Z_MEM_ERROR;
LEAVE
}
}
DUMPBITS(3)
s->mode = CODES;
break;
case 2: /* dynamic */
DUMPBITS(3)
s->mode = TABLE;
break;
case 3: /* illegal */
DUMPBITS(3)
s->mode = B_BAD;
z->msg = (char*)"invalid block type";
r = Z_DATA_ERROR;
LEAVE
}
break;
case LENS:
NEEDBITS(32)
if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
{
s->mode = B_BAD;
z->msg = (char*)"invalid stored block lengths";
r = Z_DATA_ERROR;
LEAVE
}
s->sub.left = (uInt)b & 0xffff;
b = k = 0; /* dump bits */
s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE);
break;
case STORED:
if (n == 0)
LEAVE
NEEDOUT
t = s->sub.left;
if (t > n) t = n;
if (t > m) t = m;
memcpy(q, p, t);
p += t; n -= t;
q += t; m -= t;
if ((s->sub.left -= t) != 0)
break;
s->mode = s->last ? DRY : TYPE;
break;
case TABLE:
NEEDBITS(14)
s->sub.trees.table = t = (uInt)b & 0x3fff;
#ifndef PKZIP_BUG_WORKAROUND
if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
{
s->mode = B_BAD;
z->msg = (char*)"too many length or distance symbols";
r = Z_DATA_ERROR;
LEAVE
}
#endif
{
s->sub.trees.blens = WS(z)->working_blens;
}
DUMPBITS(14)
s->sub.trees.index = 0;
s->mode = BTREE;
case BTREE:
while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10))
{
NEEDBITS(3)
s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7;
DUMPBITS(3)
}
while (s->sub.trees.index < 19)
s->sub.trees.blens[border[s->sub.trees.index++]] = 0;
s->sub.trees.bb = 7;
t = zlib_inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
&s->sub.trees.tb, s->hufts, z);
if (t != Z_OK)
{
r = t;
if (r == Z_DATA_ERROR)
s->mode = B_BAD;
LEAVE
}
s->sub.trees.index = 0;
s->mode = DTREE;
case DTREE:
while (t = s->sub.trees.table,
s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
{
inflate_huft *h;
uInt i, j, c;
t = s->sub.trees.bb;
NEEDBITS(t)
h = s->sub.trees.tb + ((uInt)b & zlib_inflate_mask[t]);
t = h->bits;
c = h->base;
if (c < 16)
{
DUMPBITS(t)
s->sub.trees.blens[s->sub.trees.index++] = c;
}
else /* c == 16..18 */
{
i = c == 18 ? 7 : c - 14;
j = c == 18 ? 11 : 3;
NEEDBITS(t + i)
DUMPBITS(t)
j += (uInt)b & zlib_inflate_mask[i];
DUMPBITS(i)
i = s->sub.trees.index;
t = s->sub.trees.table;
if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) ||
(c == 16 && i < 1))
{
s->mode = B_BAD;
z->msg = (char*)"invalid bit length repeat";
r = Z_DATA_ERROR;
LEAVE
}
c = c == 16 ? s->sub.trees.blens[i - 1] : 0;
do {
s->sub.trees.blens[i++] = c;
} while (--j);
s->sub.trees.index = i;
}
}
s->sub.trees.tb = NULL;
{
uInt bl, bd;
inflate_huft *tl, *td;
inflate_codes_statef *c;
bl = 9; /* must be <= 9 for lookahead assumptions */
bd = 6; /* must be <= 9 for lookahead assumptions */
t = s->sub.trees.table;
t = zlib_inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
s->sub.trees.blens, &bl, &bd, &tl, &td,
s->hufts, z);
if (t != Z_OK)
{
if (t == (uInt)Z_DATA_ERROR)
s->mode = B_BAD;
r = t;
LEAVE
}
if ((c = zlib_inflate_codes_new(bl, bd, tl, td, z)) == NULL)
{
r = Z_MEM_ERROR;
LEAVE
}
s->sub.decode.codes = c;
}
s->mode = CODES;
case CODES:
UPDATE
if ((r = zlib_inflate_codes(s, z, r)) != Z_STREAM_END)
return zlib_inflate_flush(s, z, r);
r = Z_OK;
zlib_inflate_codes_free(s->sub.decode.codes, z);
LOAD
if (!s->last)
{
s->mode = TYPE;
break;
}
s->mode = DRY;
case DRY:
FLUSH
if (s->read != s->write)
LEAVE
s->mode = B_DONE;
case B_DONE:
r = Z_STREAM_END;
LEAVE
case B_BAD:
r = Z_DATA_ERROR;
LEAVE
default:
r = Z_STREAM_ERROR;
LEAVE
}
}
int zlib_inflate_blocks_free(
inflate_blocks_statef *s,
z_streamp z
)
{
zlib_inflate_blocks_reset(s, z, NULL);
return Z_OK;
}
#if 0
void zlib_inflate_set_dictionary(
inflate_blocks_statef *s,
const Byte *d,
uInt n
)
{
memcpy(s->window, d, n);
s->read = s->write = s->window + n;
}
#endif /* 0 */
/* Returns true if inflate is currently at the end of a block generated
* by Z_SYNC_FLUSH or Z_FULL_FLUSH.
* IN assertion: s != NULL
*/
#if 0
int zlib_inflate_blocks_sync_point(
inflate_blocks_statef *s
)
{
return s->mode == LENS;
}
#endif /* 0 */
/* infblock.h -- header to use infblock.c
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
#ifndef _INFBLOCK_H
#define _INFBLOCK_H
struct inflate_blocks_state;
typedef struct inflate_blocks_state inflate_blocks_statef;
extern inflate_blocks_statef * zlib_inflate_blocks_new (
z_streamp z,
check_func c, /* check function */
uInt w); /* window size */
extern int zlib_inflate_blocks (
inflate_blocks_statef *,
z_streamp ,
int); /* initial return code */
extern void zlib_inflate_blocks_reset (
inflate_blocks_statef *,
z_streamp ,
uLong *); /* check value on output */
extern int zlib_inflate_blocks_free (
inflate_blocks_statef *,
z_streamp);
#if 0
extern void zlib_inflate_set_dictionary (
inflate_blocks_statef *s,
const Byte *d, /* dictionary */
uInt n); /* dictionary length */
#endif /* 0 */
#if 0
extern int zlib_inflate_blocks_sync_point (
inflate_blocks_statef *s);
#endif /* 0 */
#endif /* _INFBLOCK_H */
/* infcodes.c -- process literals and length/distance pairs
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include <linux/zutil.h>
#include "inftrees.h"
#include "infblock.h"
#include "infcodes.h"
#include "infutil.h"
#include "inffast.h"
/* simplify the use of the inflate_huft type with some defines */
#define exop word.what.Exop
#define bits word.what.Bits
inflate_codes_statef *zlib_inflate_codes_new(
uInt bl,
uInt bd,
inflate_huft *tl,
inflate_huft *td, /* need separate declaration for Borland C++ */
z_streamp z
)
{
inflate_codes_statef *c;
c = &WS(z)->working_state;
{
c->mode = START;
c->lbits = (Byte)bl;
c->dbits = (Byte)bd;
c->ltree = tl;
c->dtree = td;
}
return c;
}
int zlib_inflate_codes(
inflate_blocks_statef *s,
z_streamp z,
int r
)
{
uInt j; /* temporary storage */
inflate_huft *t; /* temporary pointer */
uInt e; /* extra bits or operation */
uLong b; /* bit buffer */
uInt k; /* bits in bit buffer */
Byte *p; /* input data pointer */
uInt n; /* bytes available there */
Byte *q; /* output window write pointer */
uInt m; /* bytes to end of window or read pointer */
Byte *f; /* pointer to copy strings from */
inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
/* copy input/output information to locals (UPDATE macro restores) */
LOAD
/* process input and output based on current state */
while (1) switch (c->mode)
{ /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
case START: /* x: set up for LEN */
#ifndef SLOW
if (m >= 258 && n >= 10)
{
UPDATE
r = zlib_inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
LOAD
if (r != Z_OK)
{
c->mode = r == Z_STREAM_END ? WASH : BADCODE;
break;
}
}
#endif /* !SLOW */
c->sub.code.need = c->lbits;
c->sub.code.tree = c->ltree;
c->mode = LEN;
case LEN: /* i: get length/literal/eob next */
j = c->sub.code.need;
NEEDBITS(j)
t = c->sub.code.tree + ((uInt)b & zlib_inflate_mask[j]);
DUMPBITS(t->bits)
e = (uInt)(t->exop);
if (e == 0) /* literal */
{
c->sub.lit = t->base;
c->mode = LIT;
break;
}
if (e & 16) /* length */
{
c->sub.copy.get = e & 15;
c->len = t->base;
c->mode = LENEXT;
break;
}
if ((e & 64) == 0) /* next table */
{
c->sub.code.need = e;
c->sub.code.tree = t + t->base;
break;
}
if (e & 32) /* end of block */
{
c->mode = WASH;
break;
}
c->mode = BADCODE; /* invalid code */
z->msg = (char*)"invalid literal/length code";
r = Z_DATA_ERROR;
LEAVE
case LENEXT: /* i: getting length extra (have base) */
j = c->sub.copy.get;
NEEDBITS(j)
c->len += (uInt)b & zlib_inflate_mask[j];
DUMPBITS(j)
c->sub.code.need = c->dbits;
c->sub.code.tree = c->dtree;
c->mode = DIST;
case DIST: /* i: get distance next */
j = c->sub.code.need;
NEEDBITS(j)
t = c->sub.code.tree + ((uInt)b & zlib_inflate_mask[j]);
DUMPBITS(t->bits)
e = (uInt)(t->exop);
if (e & 16) /* distance */
{
c->sub.copy.get = e & 15;
c->sub.copy.dist = t->base;
c->mode = DISTEXT;
break;
}
if ((e & 64) == 0) /* next table */
{
c->sub.code.need = e;
c->sub.code.tree = t + t->base;
break;
}
c->mode = BADCODE; /* invalid code */
z->msg = (char*)"invalid distance code";
r = Z_DATA_ERROR;
LEAVE
case DISTEXT: /* i: getting distance extra */
j = c->sub.copy.get;
NEEDBITS(j)
c->sub.copy.dist += (uInt)b & zlib_inflate_mask[j];
DUMPBITS(j)
c->mode = COPY;
case COPY: /* o: copying bytes in window, waiting for space */
f = q - c->sub.copy.dist;
while (f < s->window) /* modulo window size-"while" instead */
f += s->end - s->window; /* of "if" handles invalid distances */
while (c->len)
{
NEEDOUT
OUTBYTE(*f++)
if (f == s->end)
f = s->window;
c->len--;
}
c->mode = START;
break;
case LIT: /* o: got literal, waiting for output space */
NEEDOUT
OUTBYTE(c->sub.lit)
c->mode = START;
break;
case WASH: /* o: got eob, possibly more output */
if (k > 7) /* return unused byte, if any */
{
k -= 8;
n++;
p--; /* can always return one */
}
FLUSH
if (s->read != s->write)
LEAVE
c->mode = END;
case END:
r = Z_STREAM_END;
LEAVE
case BADCODE: /* x: got error */
r = Z_DATA_ERROR;
LEAVE
default:
r = Z_STREAM_ERROR;
LEAVE
}
#ifdef NEED_DUMMY_RETURN
return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
#endif
}
void zlib_inflate_codes_free(
inflate_codes_statef *c,
z_streamp z
)
{
}
/* infcodes.h -- header to use infcodes.c
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
#ifndef _INFCODES_H
#define _INFCODES_H
#include "infblock.h"
struct inflate_codes_state;
typedef struct inflate_codes_state inflate_codes_statef;
extern inflate_codes_statef *zlib_inflate_codes_new (
uInt, uInt,
inflate_huft *, inflate_huft *,
z_streamp );
extern int zlib_inflate_codes (
inflate_blocks_statef *,
z_streamp ,
int);
extern void zlib_inflate_codes_free (
inflate_codes_statef *,
z_streamp );
#endif /* _INFCODES_H */
/* inffast.c -- process literals and length/distance pairs fast
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
/* inffast.c -- fast decoding
* Copyright (C) 1995-2004 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include <linux/zutil.h>
#include "inftrees.h"
#include "infblock.h"
#include "infcodes.h"
#include "infutil.h"
#include "inflate.h"
#include "inffast.h"
struct inflate_codes_state;
/* simplify the use of the inflate_huft type with some defines */
#define exop word.what.Exop
#define bits word.what.Bits
/* macros for bit input with no checking and for returning unused bytes */
#define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}}
#define UNGRAB {c=z->avail_in-n;c=(k>>3)<c?k>>3:c;n+=c;p-=c;k-=c<<3;}
/* Called with number of bytes left to write in window at least 258
(the maximum string length) and number of input bytes available
at least ten. The ten bytes are six bytes for the longest length/
distance pair plus four bytes for overloading the bit buffer. */
int zlib_inflate_fast(
uInt bl,
uInt bd,
inflate_huft *tl,
inflate_huft *td, /* need separate declaration for Borland C++ */
inflate_blocks_statef *s,
z_streamp z
)
#ifndef ASMINF
/* Allow machine dependent optimization for post-increment or pre-increment.
Based on testing to date,
Pre-increment preferred for:
- PowerPC G3 (Adler)
- MIPS R5000 (Randers-Pehrson)
Post-increment preferred for:
- none
No measurable difference:
- Pentium III (Anderson)
- M68060 (Nikl)
*/
#ifdef POSTINC
# define OFF 0
# define PUP(a) *(a)++
#else
# define OFF 1
# define PUP(a) *++(a)
#endif
/*
Decode literal, length, and distance codes and write out the resulting
literal and match bytes until either not enough input or output is
available, an end-of-block is encountered, or a data error is encountered.
When large enough input and output buffers are supplied to inflate(), for
example, a 16K input buffer and a 64K output buffer, more than 95% of the
inflate execution time is spent in this routine.
Entry assumptions:
state->mode == LEN
strm->avail_in >= 6
strm->avail_out >= 258
start >= strm->avail_out
state->bits < 8
On return, state->mode is one of:
LEN -- ran out of enough output space or enough available input
TYPE -- reached end of block code, inflate() to interpret next block
BAD -- error in block data
Notes:
- The maximum input bits used by a length/distance pair is 15 bits for the
length code, 5 bits for the length extra, 15 bits for the distance code,
and 13 bits for the distance extra. This totals 48 bits, or six bytes.
Therefore if strm->avail_in >= 6, then there is enough input to avoid
checking for available input while decoding.
- The maximum bytes that a single length/distance pair can output is 258
bytes, which is the maximum length that can be coded. inflate_fast()
requires strm->avail_out >= 258 for each loop to avoid checking for
output space.
*/
void inflate_fast(strm, start)
z_streamp strm;
unsigned start; /* inflate()'s starting value for strm->avail_out */
{
inflate_huft *t; /* temporary pointer */
uInt e; /* extra bits or operation */
uLong b; /* bit buffer */
uInt k; /* bits in bit buffer */
Byte *p; /* input data pointer */
uInt n; /* bytes available there */
Byte *q; /* output window write pointer */
uInt m; /* bytes to end of window or read pointer */
uInt ml; /* mask for literal/length tree */
uInt md; /* mask for distance tree */
uInt c; /* bytes to copy */
uInt d; /* distance back to copy from */
Byte *r; /* copy source pointer */
/* load input, output, bit values */
LOAD
/* initialize masks */
ml = zlib_inflate_mask[bl];
md = zlib_inflate_mask[bd];
/* do until not enough input or output space for fast loop */
do { /* assume called with m >= 258 && n >= 10 */
/* get literal/length code */
GRABBITS(20) /* max bits for literal/length code */
if ((e = (t = tl + ((uInt)b & ml))->exop) == 0)
{
DUMPBITS(t->bits)
*q++ = (Byte)t->base;
m--;
continue;
}
struct inflate_state *state;
unsigned char *in; /* local strm->next_in */
unsigned char *last; /* while in < last, enough input available */
unsigned char *out; /* local strm->next_out */
unsigned char *beg; /* inflate()'s initial strm->next_out */
unsigned char *end; /* while out < end, enough space available */
#ifdef INFLATE_STRICT
unsigned dmax; /* maximum distance from zlib header */
#endif
unsigned wsize; /* window size or zero if not using window */
unsigned whave; /* valid bytes in the window */
unsigned write; /* window write index */
unsigned char *window; /* allocated sliding window, if wsize != 0 */
unsigned long hold; /* local strm->hold */
unsigned bits; /* local strm->bits */
code const *lcode; /* local strm->lencode */
code const *dcode; /* local strm->distcode */
unsigned lmask; /* mask for first level of length codes */
unsigned dmask; /* mask for first level of distance codes */
code this; /* retrieved table entry */
unsigned op; /* code bits, operation, extra bits, or */
/* window position, window bytes to copy */
unsigned len; /* match length, unused bytes */
unsigned dist; /* match distance */
unsigned char *from; /* where to copy match from */
/* copy state to local variables */
state = (struct inflate_state *)strm->state;
in = strm->next_in - OFF;
last = in + (strm->avail_in - 5);
out = strm->next_out - OFF;
beg = out - (start - strm->avail_out);
end = out + (strm->avail_out - 257);
#ifdef INFLATE_STRICT
dmax = state->dmax;
#endif
wsize = state->wsize;
whave = state->whave;
write = state->write;
window = state->window;
hold = state->hold;
bits = state->bits;
lcode = state->lencode;
dcode = state->distcode;
lmask = (1U << state->lenbits) - 1;
dmask = (1U << state->distbits) - 1;
/* decode literals and length/distances until end-of-block or not enough
input data or output space */
do {
DUMPBITS(t->bits)
if (e & 16)
{
/* get extra bits for length */
e &= 15;
c = t->base + ((uInt)b & zlib_inflate_mask[e]);
DUMPBITS(e)
/* decode distance base of block to copy */
GRABBITS(15); /* max bits for distance code */
e = (t = td + ((uInt)b & md))->exop;
do {
DUMPBITS(t->bits)
if (e & 16)
{
/* get extra bits to add to distance base */
e &= 15;
GRABBITS(e) /* get extra bits (up to 13) */
d = t->base + ((uInt)b & zlib_inflate_mask[e]);
DUMPBITS(e)
/* do the copy */
m -= c;
r = q - d;
if (r < s->window) /* wrap if needed */
{
do {
r += s->end - s->window; /* force pointer in window */
} while (r < s->window); /* covers invalid distances */
e = s->end - r;
if (c > e)
{
c -= e; /* wrapped copy */
do {
*q++ = *r++;
} while (--e);
r = s->window;
do {
*q++ = *r++;
} while (--c);
}
else /* normal copy */
{
*q++ = *r++; c--;
*q++ = *r++; c--;
do {
*q++ = *r++;
} while (--c);
}
if (bits < 15) {
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
}
this = lcode[hold & lmask];
dolen:
op = (unsigned)(this.bits);
hold >>= op;
bits -= op;
op = (unsigned)(this.op);
if (op == 0) { /* literal */
PUP(out) = (unsigned char)(this.val);
}
else if (op & 16) { /* length base */
len = (unsigned)(this.val);
op &= 15; /* number of extra bits */
if (op) {
if (bits < op) {
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
}
len += (unsigned)hold & ((1U << op) - 1);
hold >>= op;
bits -= op;
}
if (bits < 15) {
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
}
this = dcode[hold & dmask];
dodist:
op = (unsigned)(this.bits);
hold >>= op;
bits -= op;
op = (unsigned)(this.op);
if (op & 16) { /* distance base */
dist = (unsigned)(this.val);
op &= 15; /* number of extra bits */
if (bits < op) {
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
if (bits < op) {
hold += (unsigned long)(PUP(in)) << bits;
bits += 8;
}
}
dist += (unsigned)hold & ((1U << op) - 1);
#ifdef INFLATE_STRICT
if (dist > dmax) {
strm->msg = (char *)"invalid distance too far back";
state->mode = BAD;
break;
}
#endif
hold >>= op;
bits -= op;
op = (unsigned)(out - beg); /* max distance in output */
if (dist > op) { /* see if copy from window */
op = dist - op; /* distance back in window */
if (op > whave) {
strm->msg = (char *)"invalid distance too far back";
state->mode = BAD;
break;
}
from = window - OFF;
if (write == 0) { /* very common case */
from += wsize - op;
if (op < len) { /* some from window */
len -= op;
do {
PUP(out) = PUP(from);
} while (--op);
from = out - dist; /* rest from output */
}
}
else if (write < op) { /* wrap around window */
from += wsize + write - op;
op -= write;
if (op < len) { /* some from end of window */
len -= op;
do {
PUP(out) = PUP(from);
} while (--op);
from = window - OFF;
if (write < len) { /* some from start of window */
op = write;
len -= op;
do {
PUP(out) = PUP(from);
} while (--op);
from = out - dist; /* rest from output */
}
}
}
else { /* contiguous in window */
from += write - op;
if (op < len) { /* some from window */
len -= op;
do {
PUP(out) = PUP(from);
} while (--op);
from = out - dist; /* rest from output */
}
}
while (len > 2) {
PUP(out) = PUP(from);
PUP(out) = PUP(from);
PUP(out) = PUP(from);
len -= 3;
}
if (len) {
PUP(out) = PUP(from);
if (len > 1)
PUP(out) = PUP(from);
}
}
else {
from = out - dist; /* copy direct from output */
do { /* minimum length is three */
PUP(out) = PUP(from);
PUP(out) = PUP(from);
PUP(out) = PUP(from);
len -= 3;
} while (len > 2);
if (len) {
PUP(out) = PUP(from);
if (len > 1)
PUP(out) = PUP(from);
}
}
}
else if ((op & 64) == 0) { /* 2nd level distance code */
this = dcode[this.val + (hold & ((1U << op) - 1))];
goto dodist;
}
else /* normal copy */
{
*q++ = *r++; c--;
*q++ = *r++; c--;
do {
*q++ = *r++;
} while (--c);
else {
strm->msg = (char *)"invalid distance code";
state->mode = BAD;
break;
}
}
else if ((op & 64) == 0) { /* 2nd level length code */
this = lcode[this.val + (hold & ((1U << op) - 1))];
goto dolen;
}
else if (op & 32) { /* end-of-block */
state->mode = TYPE;
break;
}
else if ((e & 64) == 0)
{
t += t->base;
e = (t += ((uInt)b & zlib_inflate_mask[e]))->exop;
}
else
{
z->msg = (char*)"invalid distance code";
UNGRAB
UPDATE
return Z_DATA_ERROR;
}
} while (1);
break;
}
if ((e & 64) == 0)
{
t += t->base;
if ((e = (t += ((uInt)b & zlib_inflate_mask[e]))->exop) == 0)
{
DUMPBITS(t->bits)
*q++ = (Byte)t->base;
m--;
break;
}
}
else if (e & 32)
{
UNGRAB
UPDATE
return Z_STREAM_END;
}
else
{
z->msg = (char*)"invalid literal/length code";
UNGRAB
UPDATE
return Z_DATA_ERROR;
}
} while (1);
} while (m >= 258 && n >= 10);
/* not enough input or output--restore pointers and return */
UNGRAB
UPDATE
return Z_OK;
else {
strm->msg = (char *)"invalid literal/length code";
state->mode = BAD;
break;
}
} while (in < last && out < end);
/* return unused bytes (on entry, bits < 8, so in won't go too far back) */
len = bits >> 3;
in -= len;
bits -= len << 3;
hold &= (1U << bits) - 1;
/* update state and return */
strm->next_in = in + OFF;
strm->next_out = out + OFF;
strm->avail_in = (unsigned)(in < last ? 5 + (last - in) : 5 - (in - last));
strm->avail_out = (unsigned)(out < end ?
257 + (end - out) : 257 - (out - end));
state->hold = hold;
state->bits = bits;
return;
}
/*
inflate_fast() speedups that turned out slower (on a PowerPC G3 750CXe):
- Using bit fields for code structure
- Different op definition to avoid & for extra bits (do & for table bits)
- Three separate decoding do-loops for direct, window, and write == 0
- Special case for distance > 1 copies to do overlapped load and store copy
- Explicit branch predictions (based on measured branch probabilities)
- Deferring match copy and interspersed it with decoding subsequent codes
- Swapping literal/length else
- Swapping window/direct else
- Larger unrolled copy loops (three is about right)
- Moving len -= 3 statement into middle of loop
*/
#endif /* !ASMINF */
/* inffast.h -- header to use inffast.c
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
* Copyright (C) 1995-2003 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
......@@ -8,10 +8,4 @@
subject to change. Applications should only use zlib.h.
*/
extern int zlib_inflate_fast (
uInt,
uInt,
inflate_huft *,
inflate_huft *,
inflate_blocks_statef *,
z_streamp );
void inflate_fast (z_streamp strm, unsigned start);
/* inffixed.h -- table for decoding fixed codes
* Generated automatically by makefixed().
*/
/* WARNING: this file should *not* be used by applications. It
is part of the implementation of the compression library and
is subject to change. Applications should only use zlib.h.
*/
static const code lenfix[512] = {
{96,7,0},{0,8,80},{0,8,16},{20,8,115},{18,7,31},{0,8,112},{0,8,48},
{0,9,192},{16,7,10},{0,8,96},{0,8,32},{0,9,160},{0,8,0},{0,8,128},
{0,8,64},{0,9,224},{16,7,6},{0,8,88},{0,8,24},{0,9,144},{19,7,59},
{0,8,120},{0,8,56},{0,9,208},{17,7,17},{0,8,104},{0,8,40},{0,9,176},
{0,8,8},{0,8,136},{0,8,72},{0,9,240},{16,7,4},{0,8,84},{0,8,20},
{21,8,227},{19,7,43},{0,8,116},{0,8,52},{0,9,200},{17,7,13},{0,8,100},
{0,8,36},{0,9,168},{0,8,4},{0,8,132},{0,8,68},{0,9,232},{16,7,8},
{0,8,92},{0,8,28},{0,9,152},{20,7,83},{0,8,124},{0,8,60},{0,9,216},
{18,7,23},{0,8,108},{0,8,44},{0,9,184},{0,8,12},{0,8,140},{0,8,76},
{0,9,248},{16,7,3},{0,8,82},{0,8,18},{21,8,163},{19,7,35},{0,8,114},
{0,8,50},{0,9,196},{17,7,11},{0,8,98},{0,8,34},{0,9,164},{0,8,2},
{0,8,130},{0,8,66},{0,9,228},{16,7,7},{0,8,90},{0,8,26},{0,9,148},
{20,7,67},{0,8,122},{0,8,58},{0,9,212},{18,7,19},{0,8,106},{0,8,42},
{0,9,180},{0,8,10},{0,8,138},{0,8,74},{0,9,244},{16,7,5},{0,8,86},
{0,8,22},{64,8,0},{19,7,51},{0,8,118},{0,8,54},{0,9,204},{17,7,15},
{0,8,102},{0,8,38},{0,9,172},{0,8,6},{0,8,134},{0,8,70},{0,9,236},
{16,7,9},{0,8,94},{0,8,30},{0,9,156},{20,7,99},{0,8,126},{0,8,62},
{0,9,220},{18,7,27},{0,8,110},{0,8,46},{0,9,188},{0,8,14},{0,8,142},
{0,8,78},{0,9,252},{96,7,0},{0,8,81},{0,8,17},{21,8,131},{18,7,31},
{0,8,113},{0,8,49},{0,9,194},{16,7,10},{0,8,97},{0,8,33},{0,9,162},
{0,8,1},{0,8,129},{0,8,65},{0,9,226},{16,7,6},{0,8,89},{0,8,25},
{0,9,146},{19,7,59},{0,8,121},{0,8,57},{0,9,210},{17,7,17},{0,8,105},
{0,8,41},{0,9,178},{0,8,9},{0,8,137},{0,8,73},{0,9,242},{16,7,4},
{0,8,85},{0,8,21},{16,8,258},{19,7,43},{0,8,117},{0,8,53},{0,9,202},
{17,7,13},{0,8,101},{0,8,37},{0,9,170},{0,8,5},{0,8,133},{0,8,69},
{0,9,234},{16,7,8},{0,8,93},{0,8,29},{0,9,154},{20,7,83},{0,8,125},
{0,8,61},{0,9,218},{18,7,23},{0,8,109},{0,8,45},{0,9,186},{0,8,13},
{0,8,141},{0,8,77},{0,9,250},{16,7,3},{0,8,83},{0,8,19},{21,8,195},
{19,7,35},{0,8,115},{0,8,51},{0,9,198},{17,7,11},{0,8,99},{0,8,35},
{0,9,166},{0,8,3},{0,8,131},{0,8,67},{0,9,230},{16,7,7},{0,8,91},
{0,8,27},{0,9,150},{20,7,67},{0,8,123},{0,8,59},{0,9,214},{18,7,19},
{0,8,107},{0,8,43},{0,9,182},{0,8,11},{0,8,139},{0,8,75},{0,9,246},
{16,7,5},{0,8,87},{0,8,23},{64,8,0},{19,7,51},{0,8,119},{0,8,55},
{0,9,206},{17,7,15},{0,8,103},{0,8,39},{0,9,174},{0,8,7},{0,8,135},
{0,8,71},{0,9,238},{16,7,9},{0,8,95},{0,8,31},{0,9,158},{20,7,99},
{0,8,127},{0,8,63},{0,9,222},{18,7,27},{0,8,111},{0,8,47},{0,9,190},
{0,8,15},{0,8,143},{0,8,79},{0,9,254},{96,7,0},{0,8,80},{0,8,16},
{20,8,115},{18,7,31},{0,8,112},{0,8,48},{0,9,193},{16,7,10},{0,8,96},
{0,8,32},{0,9,161},{0,8,0},{0,8,128},{0,8,64},{0,9,225},{16,7,6},
{0,8,88},{0,8,24},{0,9,145},{19,7,59},{0,8,120},{0,8,56},{0,9,209},
{17,7,17},{0,8,104},{0,8,40},{0,9,177},{0,8,8},{0,8,136},{0,8,72},
{0,9,241},{16,7,4},{0,8,84},{0,8,20},{21,8,227},{19,7,43},{0,8,116},
{0,8,52},{0,9,201},{17,7,13},{0,8,100},{0,8,36},{0,9,169},{0,8,4},
{0,8,132},{0,8,68},{0,9,233},{16,7,8},{0,8,92},{0,8,28},{0,9,153},
{20,7,83},{0,8,124},{0,8,60},{0,9,217},{18,7,23},{0,8,108},{0,8,44},
{0,9,185},{0,8,12},{0,8,140},{0,8,76},{0,9,249},{16,7,3},{0,8,82},
{0,8,18},{21,8,163},{19,7,35},{0,8,114},{0,8,50},{0,9,197},{17,7,11},
{0,8,98},{0,8,34},{0,9,165},{0,8,2},{0,8,130},{0,8,66},{0,9,229},
{16,7,7},{0,8,90},{0,8,26},{0,9,149},{20,7,67},{0,8,122},{0,8,58},
{0,9,213},{18,7,19},{0,8,106},{0,8,42},{0,9,181},{0,8,10},{0,8,138},
{0,8,74},{0,9,245},{16,7,5},{0,8,86},{0,8,22},{64,8,0},{19,7,51},
{0,8,118},{0,8,54},{0,9,205},{17,7,15},{0,8,102},{0,8,38},{0,9,173},
{0,8,6},{0,8,134},{0,8,70},{0,9,237},{16,7,9},{0,8,94},{0,8,30},
{0,9,157},{20,7,99},{0,8,126},{0,8,62},{0,9,221},{18,7,27},{0,8,110},
{0,8,46},{0,9,189},{0,8,14},{0,8,142},{0,8,78},{0,9,253},{96,7,0},
{0,8,81},{0,8,17},{21,8,131},{18,7,31},{0,8,113},{0,8,49},{0,9,195},
{16,7,10},{0,8,97},{0,8,33},{0,9,163},{0,8,1},{0,8,129},{0,8,65},
{0,9,227},{16,7,6},{0,8,89},{0,8,25},{0,9,147},{19,7,59},{0,8,121},
{0,8,57},{0,9,211},{17,7,17},{0,8,105},{0,8,41},{0,9,179},{0,8,9},
{0,8,137},{0,8,73},{0,9,243},{16,7,4},{0,8,85},{0,8,21},{16,8,258},
{19,7,43},{0,8,117},{0,8,53},{0,9,203},{17,7,13},{0,8,101},{0,8,37},
{0,9,171},{0,8,5},{0,8,133},{0,8,69},{0,9,235},{16,7,8},{0,8,93},
{0,8,29},{0,9,155},{20,7,83},{0,8,125},{0,8,61},{0,9,219},{18,7,23},
{0,8,109},{0,8,45},{0,9,187},{0,8,13},{0,8,141},{0,8,77},{0,9,251},
{16,7,3},{0,8,83},{0,8,19},{21,8,195},{19,7,35},{0,8,115},{0,8,51},
{0,9,199},{17,7,11},{0,8,99},{0,8,35},{0,9,167},{0,8,3},{0,8,131},
{0,8,67},{0,9,231},{16,7,7},{0,8,91},{0,8,27},{0,9,151},{20,7,67},
{0,8,123},{0,8,59},{0,9,215},{18,7,19},{0,8,107},{0,8,43},{0,9,183},
{0,8,11},{0,8,139},{0,8,75},{0,9,247},{16,7,5},{0,8,87},{0,8,23},
{64,8,0},{19,7,51},{0,8,119},{0,8,55},{0,9,207},{17,7,15},{0,8,103},
{0,8,39},{0,9,175},{0,8,7},{0,8,135},{0,8,71},{0,9,239},{16,7,9},
{0,8,95},{0,8,31},{0,9,159},{20,7,99},{0,8,127},{0,8,63},{0,9,223},
{18,7,27},{0,8,111},{0,8,47},{0,9,191},{0,8,15},{0,8,143},{0,8,79},
{0,9,255}
};
static const code distfix[32] = {
{16,5,1},{23,5,257},{19,5,17},{27,5,4097},{17,5,5},{25,5,1025},
{21,5,65},{29,5,16385},{16,5,3},{24,5,513},{20,5,33},{28,5,8193},
{18,5,9},{26,5,2049},{22,5,129},{64,5,0},{16,5,2},{23,5,385},
{19,5,25},{27,5,6145},{17,5,7},{25,5,1537},{21,5,97},{29,5,24577},
{16,5,4},{24,5,769},{20,5,49},{28,5,12289},{18,5,13},{26,5,3073},
{22,5,193},{64,5,0}
};
此差异已折叠。
/* inflate.h -- internal inflate state definition
* Copyright (C) 1995-2004 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
part of the implementation of the compression library and is
subject to change. Applications should only use zlib.h.
*/
/* Possible inflate modes between inflate() calls */
typedef enum {
HEAD, /* i: waiting for magic header */
FLAGS, /* i: waiting for method and flags (gzip) */
TIME, /* i: waiting for modification time (gzip) */
OS, /* i: waiting for extra flags and operating system (gzip) */
EXLEN, /* i: waiting for extra length (gzip) */
EXTRA, /* i: waiting for extra bytes (gzip) */
NAME, /* i: waiting for end of file name (gzip) */
COMMENT, /* i: waiting for end of comment (gzip) */
HCRC, /* i: waiting for header crc (gzip) */
DICTID, /* i: waiting for dictionary check value */
DICT, /* waiting for inflateSetDictionary() call */
TYPE, /* i: waiting for type bits, including last-flag bit */
TYPEDO, /* i: same, but skip check to exit inflate on new block */
STORED, /* i: waiting for stored size (length and complement) */
COPY, /* i/o: waiting for input or output to copy stored block */
TABLE, /* i: waiting for dynamic block table lengths */
LENLENS, /* i: waiting for code length code lengths */
CODELENS, /* i: waiting for length/lit and distance code lengths */
LEN, /* i: waiting for length/lit code */
LENEXT, /* i: waiting for length extra bits */
DIST, /* i: waiting for distance code */
DISTEXT, /* i: waiting for distance extra bits */
MATCH, /* o: waiting for output space to copy string */
LIT, /* o: waiting for output space to write literal */
CHECK, /* i: waiting for 32-bit check value */
LENGTH, /* i: waiting for 32-bit length (gzip) */
DONE, /* finished check, done -- remain here until reset */
BAD, /* got a data error -- remain here until reset */
MEM, /* got an inflate() memory error -- remain here until reset */
SYNC /* looking for synchronization bytes to restart inflate() */
} inflate_mode;
/*
State transitions between above modes -
(most modes can go to the BAD or MEM mode -- not shown for clarity)
Process header:
HEAD -> (gzip) or (zlib)
(gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME
NAME -> COMMENT -> HCRC -> TYPE
(zlib) -> DICTID or TYPE
DICTID -> DICT -> TYPE
Read deflate blocks:
TYPE -> STORED or TABLE or LEN or CHECK
STORED -> COPY -> TYPE
TABLE -> LENLENS -> CODELENS -> LEN
Read deflate codes:
LEN -> LENEXT or LIT or TYPE
LENEXT -> DIST -> DISTEXT -> MATCH -> LEN
LIT -> LEN
Process trailer:
CHECK -> LENGTH -> DONE
*/
/* state maintained between inflate() calls. Approximately 7K bytes. */
struct inflate_state {
inflate_mode mode; /* current inflate mode */
int last; /* true if processing last block */
int wrap; /* bit 0 true for zlib, bit 1 true for gzip */
int havedict; /* true if dictionary provided */
int flags; /* gzip header method and flags (0 if zlib) */
unsigned dmax; /* zlib header max distance (INFLATE_STRICT) */
unsigned long check; /* protected copy of check value */
unsigned long total; /* protected copy of output count */
/* gz_headerp head; */ /* where to save gzip header information */
/* sliding window */
unsigned wbits; /* log base 2 of requested window size */
unsigned wsize; /* window size or zero if not using window */
unsigned whave; /* valid bytes in the window */
unsigned write; /* window write index */
unsigned char *window; /* allocated sliding window, if needed */
/* bit accumulator */
unsigned long hold; /* input bit accumulator */
unsigned bits; /* number of bits in "in" */
/* for string and stored block copying */
unsigned length; /* literal or length of data to copy */
unsigned offset; /* distance back to copy string from */
/* for table and code decoding */
unsigned extra; /* extra bits needed */
/* fixed and dynamic code tables */
code const *lencode; /* starting table for length/literal codes */
code const *distcode; /* starting table for distance codes */
unsigned lenbits; /* index bits for lencode */
unsigned distbits; /* index bits for distcode */
/* dynamic table building */
unsigned ncode; /* number of code length code lengths */
unsigned nlen; /* number of length code lengths */
unsigned ndist; /* number of distance code lengths */
unsigned have; /* number of code lengths in lens[] */
code *next; /* next available space in codes[] */
unsigned short lens[320]; /* temporary storage for code lengths */
unsigned short work[288]; /* work area for code table building */
code codes[ENOUGH]; /* space for code tables */
};
......@@ -12,8 +12,7 @@
EXPORT_SYMBOL(zlib_inflate_workspacesize);
EXPORT_SYMBOL(zlib_inflate);
EXPORT_SYMBOL(zlib_inflateInit_);
EXPORT_SYMBOL(zlib_inflateInit2_);
EXPORT_SYMBOL(zlib_inflateInit2);
EXPORT_SYMBOL(zlib_inflateEnd);
EXPORT_SYMBOL(zlib_inflateReset);
EXPORT_SYMBOL(zlib_inflateIncomp);
......
/* inflate.c -- zlib interface to inflate modules
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include <linux/zutil.h>
#include "infblock.h"
#include "infutil.h"
#if 0
int zlib_inflateSync(
z_streamp z
)
{
uInt n; /* number of bytes to look at */
Byte *p; /* pointer to bytes */
uInt m; /* number of marker bytes found in a row */
uLong r, w; /* temporaries to save total_in and total_out */
/* set up */
if (z == NULL || z->state == NULL)
return Z_STREAM_ERROR;
if (z->state->mode != I_BAD)
{
z->state->mode = I_BAD;
z->state->sub.marker = 0;
}
if ((n = z->avail_in) == 0)
return Z_BUF_ERROR;
p = z->next_in;
m = z->state->sub.marker;
/* search */
while (n && m < 4)
{
static const Byte mark[4] = {0, 0, 0xff, 0xff};
if (*p == mark[m])
m++;
else if (*p)
m = 0;
else
m = 4 - m;
p++, n--;
}
/* restore */
z->total_in += p - z->next_in;
z->next_in = p;
z->avail_in = n;
z->state->sub.marker = m;
/* return no joy or set up to restart on a new block */
if (m != 4)
return Z_DATA_ERROR;
r = z->total_in; w = z->total_out;
zlib_inflateReset(z);
z->total_in = r; z->total_out = w;
z->state->mode = BLOCKS;
return Z_OK;
}
#endif /* 0 */
/* 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.
*/
#if 0
int zlib_inflateSyncPoint(
z_streamp z
)
{
if (z == NULL || z->state == NULL || z->state->blocks == NULL)
return Z_STREAM_ERROR;
return zlib_inflate_blocks_sync_point(z->state->blocks);
}
#endif /* 0 */
/*
* This subroutine adds the data at next_in/avail_in to the output history
* without performing any output. The output buffer must be "caught up";
* i.e. no pending output (hence s->read equals s->write), and the state must
* be BLOCKS (i.e. we should be willing to see the start of a series of
* BLOCKS). On exit, the output will also be caught up, and the checksum
* will have been updated if need be.
*/
static int zlib_inflate_addhistory(inflate_blocks_statef *s,
z_stream *z)
{
uLong b; /* bit buffer */ /* NOT USED HERE */
uInt k; /* bits in bit buffer */ /* NOT USED HERE */
uInt t; /* temporary storage */
Byte *p; /* input data pointer */
uInt n; /* bytes available there */
Byte *q; /* output window write pointer */
uInt m; /* bytes to end of window or read pointer */
if (s->read != s->write)
return Z_STREAM_ERROR;
if (s->mode != TYPE)
return Z_DATA_ERROR;
/* we're ready to rock */
LOAD
/* while there is input ready, copy to output buffer, moving
* pointers as needed.
*/
while (n) {
t = n; /* how many to do */
/* is there room until end of buffer? */
if (t > m) t = m;
/* update check information */
if (s->checkfn != NULL)
s->check = (*s->checkfn)(s->check, q, t);
memcpy(q, p, t);
q += t;
p += t;
n -= t;
z->total_out += t;
s->read = q; /* drag read pointer forward */
/* WWRAP */ /* expand WWRAP macro by hand to handle s->read */
if (q == s->end) {
s->read = q = s->window;
m = WAVAIL;
}
}
UPDATE
return Z_OK;
}
/*
* This subroutine adds the data at next_in/avail_in to the output history
* without performing any output. The output buffer must be "caught up";
* i.e. no pending output (hence s->read equals s->write), and the state must
* be BLOCKS (i.e. we should be willing to see the start of a series of
* BLOCKS). On exit, the output will also be caught up, and the checksum
* will have been updated if need be.
*/
int zlib_inflateIncomp(
z_stream *z
)
{
if (z->state->mode != BLOCKS)
return Z_DATA_ERROR;
return zlib_inflate_addhistory(z->state->blocks, z);
}
此差异已折叠。
/* inftrees.h -- header to use inftrees.c
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
* Copyright (C) 1995-2005 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* WARNING: this file should *not* be used by applications. It is
......@@ -8,57 +8,48 @@
subject to change. Applications should only use zlib.h.
*/
/* Huffman code lookup table entry--this entry is four bytes for machines
that have 16-bit pointers (e.g. PC's in the small or medium model). */
#ifndef _INFTREES_H
#define _INFTREES_H
typedef struct inflate_huft_s inflate_huft;
struct inflate_huft_s {
union {
struct {
Byte Exop; /* number of extra bits or operation */
Byte Bits; /* number of bits in this code or subcode */
} what;
uInt pad; /* pad structure to a power of 2 (4 bytes for */
} word; /* 16-bit, 8 bytes for 32-bit int's) */
uInt base; /* literal, length base, distance base,
or table offset */
};
/* Structure for decoding tables. Each entry provides either the
information needed to do the operation requested by the code that
indexed that table entry, or it provides a pointer to another
table that indexes more bits of the code. op indicates whether
the entry is a pointer to another table, a literal, a length or
distance, an end-of-block, or an invalid code. For a table
pointer, the low four bits of op is the number of index bits of
that table. For a length or distance, the low four bits of op
is the number of extra bits to get after the code. bits is
the number of bits in this code or part of the code to drop off
of the bit buffer. val is the actual byte to output in the case
of a literal, the base length or distance, or the offset from
the current table to the next table. Each entry is four bytes. */
typedef struct {
unsigned char op; /* operation, extra bits, table bits */
unsigned char bits; /* bits in this part of the code */
unsigned short val; /* offset in table or code value */
} code;
/* op values as set by inflate_table():
00000000 - literal
0000tttt - table link, tttt != 0 is the number of table index bits
0001eeee - length or distance, eeee is the number of extra bits
01100000 - end of block
01000000 - invalid code
*/
/* Maximum size of dynamic tree. The maximum found in a long but non-
exhaustive search was 1004 huft structures (850 for length/literals
and 154 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 zlib_inflate_trees_bits (
uInt *, /* 19 code lengths */
uInt *, /* bits tree desired/actual depth */
inflate_huft **, /* bits tree result */
inflate_huft *, /* space for trees */
z_streamp); /* for messages */
extern int zlib_inflate_trees_dynamic (
uInt, /* number of literal/length codes */
uInt, /* number of distance codes */
uInt *, /* that many (total) code lengths */
uInt *, /* literal desired/actual bit depth */
uInt *, /* distance desired/actual bit depth */
inflate_huft **, /* literal/length tree result */
inflate_huft **, /* distance tree result */
inflate_huft *, /* space for trees */
z_streamp); /* for messages */
extern int zlib_inflate_trees_fixed (
uInt *, /* literal desired/actual bit depth */
uInt *, /* distance desired/actual bit depth */
inflate_huft **, /* literal/length tree result */
inflate_huft **, /* distance tree result */
inflate_huft *, /* space for trees */
z_streamp); /* for memory allocation */
#endif /* _INFTREES_H */
exhaustive search was 1444 code structures (852 for length/literals
and 592 for distances, the latter actually the result of an
exhaustive search). The true maximum is not known, but the value
below is more than safe. */
#define ENOUGH 2048
#define MAXD 592
/* Type of code to build for inftable() */
typedef enum {
CODES,
LENS,
DISTS
} codetype;
extern int zlib_inflate_table (codetype type, unsigned short *lens,
unsigned codes, code **table,
unsigned *bits, unsigned short *work);
/* inflate_util.c -- data and routines common to blocks and codes
* Copyright (C) 1995-1998 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include <linux/zutil.h>
#include "infblock.h"
#include "inftrees.h"
#include "infcodes.h"
#include "infutil.h"
struct inflate_codes_state;
/* And'ing with mask[n] masks the lower n bits */
uInt zlib_inflate_mask[17] = {
0x0000,
0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
};
/* copy as much as possible from the sliding window to the output area */
int zlib_inflate_flush(
inflate_blocks_statef *s,
z_streamp z,
int r
)
{
uInt n;
Byte *p;
Byte *q;
/* local copies of source and destination pointers */
p = z->next_out;
q = s->read;
/* compute number of bytes to copy as far as end of window */
n = (uInt)((q <= s->write ? s->write : s->end) - q);
if (n > z->avail_out) n = z->avail_out;
if (n && r == Z_BUF_ERROR) r = Z_OK;
/* update counters */
z->avail_out -= n;
z->total_out += n;
/* update check information */
if (s->checkfn != NULL)
z->adler = s->check = (*s->checkfn)(s->check, q, n);
/* copy as far as end of window */
memcpy(p, q, n);
p += n;
q += n;
/* see if more to copy at beginning of window */
if (q == s->end)
{
/* wrap pointers */
q = s->window;
if (s->write == s->end)
s->write = s->window;
/* compute bytes to copy */
n = (uInt)(s->write - q);
if (n > z->avail_out) n = z->avail_out;
if (n && r == Z_BUF_ERROR) r = Z_OK;
/* update counters */
z->avail_out -= n;
z->total_out += n;
/* update check information */
if (s->checkfn != NULL)
z->adler = s->check = (*s->checkfn)(s->check, q, n);
/* copy */
memcpy(p, q, n);
p += n;
q += n;
}
/* update pointers */
z->next_out = p;
s->read = q;
/* done */
return r;
}
......@@ -11,184 +11,12 @@
#ifndef _INFUTIL_H
#define _INFUTIL_H
#include <linux/zconf.h>
#include "inftrees.h"
#include "infcodes.h"
typedef enum {
TYPE, /* get type bits (3, including end bit) */
LENS, /* get lengths for stored */
STORED, /* processing stored block */
TABLE, /* get table lengths */
BTREE, /* get bit lengths tree for a dynamic block */
DTREE, /* get length, distance trees for a dynamic block */
CODES, /* processing fixed or dynamic block */
DRY, /* output remaining window bytes */
B_DONE, /* finished last block, done */
B_BAD} /* got a data error--stuck here */
inflate_block_mode;
/* inflate blocks semi-private state */
struct inflate_blocks_state {
/* mode */
inflate_block_mode mode; /* current inflate_block mode */
/* mode dependent information */
union {
uInt left; /* if STORED, bytes left to copy */
struct {
uInt table; /* table lengths (14 bits) */
uInt index; /* index into blens (or border) */
uInt *blens; /* bit lengths of codes */
uInt bb; /* bit length tree depth */
inflate_huft *tb; /* bit length decoding tree */
} trees; /* if DTREE, decoding info for trees */
struct {
inflate_codes_statef
*codes;
} decode; /* if CODES, current state */
} sub; /* submode */
uInt last; /* true if this block is the last block */
/* mode independent information */
uInt bitk; /* bits in bit buffer */
uLong bitb; /* bit buffer */
inflate_huft *hufts; /* single malloc for tree space */
Byte *window; /* sliding window */
Byte *end; /* one byte after sliding window */
Byte *read; /* window read pointer */
Byte *write; /* window write pointer */
check_func checkfn; /* check function */
uLong check; /* check on output */
};
/* defines for inflate input/output */
/* update pointers and return */
#define UPDBITS {s->bitb=b;s->bitk=k;}
#define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;}
#define UPDOUT {s->write=q;}
#define UPDATE {UPDBITS UPDIN UPDOUT}
#define LEAVE {UPDATE return zlib_inflate_flush(s,z,r);}
/* get bytes and bits */
#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
#define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
#define NEXTBYTE (n--,*p++)
#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
#define DUMPBITS(j) {b>>=(j);k-=(j);}
/* output bytes */
#define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
#define LOADOUT {q=s->write;m=(uInt)WAVAIL;}
#define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
#define FLUSH {UPDOUT r=zlib_inflate_flush(s,z,r); LOADOUT}
#define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
#define OUTBYTE(a) {*q++=(Byte)(a);m--;}
/* load local pointers */
#define LOAD {LOADIN LOADOUT}
/* masks for lower bits (size given to avoid silly warnings with Visual C++) */
extern uInt zlib_inflate_mask[17];
/* copy as much as possible from the sliding window to the output area */
extern int zlib_inflate_flush (
inflate_blocks_statef *,
z_streamp ,
int);
/* inflate private state */
typedef enum {
METHOD, /* waiting for method byte */
FLAG, /* waiting for flag byte */
DICT4, /* four dictionary check bytes to go */
DICT3, /* three dictionary check bytes to go */
DICT2, /* two dictionary check bytes to go */
DICT1, /* one dictionary check byte to go */
DICT0, /* waiting for inflateSetDictionary */
BLOCKS, /* decompressing blocks */
CHECK4, /* four check bytes to go */
CHECK3, /* three check bytes to go */
CHECK2, /* two check bytes to go */
CHECK1, /* one check byte to go */
I_DONE, /* finished check, done */
I_BAD} /* got an error--stay here */
inflate_mode;
struct internal_state {
/* mode */
inflate_mode mode; /* current inflate mode */
/* mode dependent information */
union {
uInt method; /* if FLAGS, method byte */
struct {
uLong was; /* computed check value */
uLong need; /* stream check value */
} check; /* if CHECK, check values to compare */
uInt marker; /* if BAD, inflateSync's marker bytes count */
} sub; /* submode */
/* mode independent information */
int nowrap; /* flag for no wrapper */
uInt wbits; /* log2(window size) (8..15, defaults to 15) */
inflate_blocks_statef
*blocks; /* current inflate_blocks state */
};
/* inflate codes private state */
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) */
DIST, /* i: get distance next */
DISTEXT, /* i: getting distance extra */
COPY, /* o: copying bytes in window, waiting for space */
LIT, /* o: got literal, waiting for output space */
WASH, /* o: got eob, possibly still output waiting */
END, /* x: got eob and all data flushed */
BADCODE} /* x: got error */
inflate_codes_mode;
struct inflate_codes_state {
/* mode */
inflate_codes_mode mode; /* current inflate_codes mode */
/* mode dependent information */
uInt len;
union {
struct {
inflate_huft *tree; /* pointer into tree */
uInt need; /* bits needed */
} code; /* if LEN or DIST, where in tree */
uInt lit; /* if LIT, literal */
struct {
uInt get; /* bits to get for extra */
uInt dist; /* distance back to copy from */
} copy; /* if EXT or COPY, where and how much */
} sub; /* submode */
/* mode independent information */
Byte lbits; /* ltree bits decoded per branch */
Byte dbits; /* dtree bits decoder per branch */
inflate_huft *ltree; /* literal/length/eob tree */
inflate_huft *dtree; /* distance tree */
};
#include <linux/zlib.h>
/* memory allocation for inflation */
struct inflate_workspace {
inflate_codes_statef working_state;
struct inflate_blocks_state working_blocks_state;
struct internal_state internal_state;
unsigned int tree_work_area_1[19];
unsigned int tree_work_area_2[288];
unsigned working_blens[258 + 0x1f + 0x1f];
inflate_huft working_hufts[MANY];
struct inflate_state inflate_state;
unsigned char working_window[1 << MAX_WBITS];
};
......
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