Commit 4f3865fb authored by Richard Purdie's avatar Richard Purdie Committed by 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: default avatarRichard Purdie <rpurdie@rpsys.net>
Acked-by: default avatarJoern Engel <joern@wh.fh-wedel.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 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 */
......
This diff is collapsed.
......@@ -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
This diff is collapsed.
/* 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 */
This diff is collapsed.
/* 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}
};
This diff is collapsed.
/* 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