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/*
* This file is derived from various .h and .c files from the zlib-0.95
* distribution by Jean-loup Gailly and Mark Adler, with some additions
* by Paul Mackerras to aid in implementing Deflate compression and
* decompression for PPP packets. See zlib.h for conditions of
* distribution and use.
*
* Changes that have been made include:
* - changed functions not used outside this file to "local"
* - added minCompression parameter to deflateInit2
* - added Z_PACKET_FLUSH (see zlib.h for details)
* - added inflateIncomp
*/
/*+++++*/
/* zutil.h -- internal interface and configuration of the compression library
* Copyright (C) 1995 Jean-loup Gailly.
* 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.
*/
/* From: zutil.h,v 1.9 1995/05/03 17:27:12 jloup Exp */
#define _Z_UTIL_H
#include "u-boot/zlib.h"
#ifndef local
# define local static
#endif
/* compile with -Dlocal if your debugger can't find static symbols */
#define FAR
typedef unsigned char uch;
typedef uch FAR uchf;
typedef unsigned short ush;
typedef ush FAR ushf;
typedef unsigned long ulg;
extern char *z_errmsg[]; /* indexed by 1-zlib_error */
#define ERR_RETURN(strm,err) return (strm->msg=z_errmsg[1-err], err)
/* To be used only when the state is known to be valid */
#ifndef NULL
#define NULL ((void *) 0)
#endif
#define DEFLATED 8
#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
/* The three kinds of block type */
#define MIN_MATCH 3
#define MAX_MATCH 258
/* The minimum and maximum match lengths */
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#include <linux/string.h>
#define zmemcpy memcpy
#define zmemzero(dest, len) memset(dest, 0, len)
/* Diagnostic functions */
#ifdef DEBUG_ZLIB
# include <stdio.h>
# ifndef verbose
# define verbose 0
# endif
# define Assert(cond,msg) {if(!(cond)) z_error(msg);}
# define Trace(x) fprintf x
# define Tracev(x) {if (verbose) fprintf x ;}
# define Tracevv(x) {if (verbose>1) fprintf x ;}
# define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
#else
# define Assert(cond,msg)
# define Trace(x)
# define Tracev(x)
# define Tracevv(x)
# define Tracec(c,x)
# define Tracecv(c,x)
#endif
typedef uLong (*check_func) OF((uLong check, Bytef *buf, uInt len));
/* voidpf zcalloc OF((voidpf opaque, unsigned items, unsigned size)); */
/* void zcfree OF((voidpf opaque, voidpf ptr)); */
#define ZALLOC(strm, items, size) \
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#define ZFREE(strm, addr, size) \
(*((strm)->zfree))((strm)->opaque, (voidpf)(addr), (size))
#define TRY_FREE(s, p, n) {if (p) ZFREE(s, p, n);}
/* deflate.h -- internal compression state
* Copyright (C) 1995 Jean-loup Gailly
* 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.
*/
/*+++++*/
/* infblock.h -- header to use infblock.c
* Copyright (C) 1995 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.
*/
struct inflate_blocks_state;
typedef struct inflate_blocks_state FAR inflate_blocks_statef;
local inflate_blocks_statef * inflate_blocks_new OF((
z_stream *z,
check_func c, /* check function */
uInt w)); /* window size */
local int inflate_blocks OF((
inflate_blocks_statef *,
z_stream *,
int)); /* initial return code */
local void inflate_blocks_reset OF((
inflate_blocks_statef *,
z_stream *,
uLongf *)); /* check value on output */
local int inflate_blocks_free OF((
inflate_blocks_statef *,
z_stream *,
uLongf *)); /* check value on output */
local int inflate_addhistory OF((
inflate_blocks_statef *,
z_stream *));
local int inflate_packet_flush OF((
inflate_blocks_statef *));
/*+++++*/
/* inftrees.h -- header to use inftrees.c
* Copyright (C) 1995 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.
*/
/* 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). */
typedef struct inflate_huft_s FAR 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 Nalloc; /* number of these allocated here */
Bytef *pad; /* pad structure to a power of 2 (4 bytes for */
} word; /* 16-bit, 8 bytes for 32-bit machines) */
union {
uInt Base; /* literal, length base, or distance base */
inflate_huft *Next; /* pointer to next level of table */
} more;
};
#ifdef DEBUG_ZLIB
local uInt inflate_hufts;
#endif
local int inflate_trees_bits OF((
uIntf *, /* 19 code lengths */
uIntf *, /* bits tree desired/actual depth */
inflate_huft * FAR *, /* bits tree result */
z_stream *)); /* for zalloc, zfree functions */
local int inflate_trees_dynamic OF((
uInt, /* number of literal/length codes */
uInt, /* number of distance codes */
uIntf *, /* that many (total) code lengths */
uIntf *, /* literal desired/actual bit depth */
uIntf *, /* distance desired/actual bit depth */
inflate_huft * FAR *, /* literal/length tree result */
inflate_huft * FAR *, /* distance tree result */
z_stream *)); /* for zalloc, zfree functions */
local int inflate_trees_fixed OF((
uIntf *, /* literal desired/actual bit depth */
uIntf *, /* distance desired/actual bit depth */
inflate_huft * FAR *, /* literal/length tree result */
inflate_huft * FAR *)); /* distance tree result */
local int inflate_trees_free OF((
inflate_huft *, /* tables to free */
z_stream *)); /* for zfree function */
/*+++++*/
/* infcodes.h -- header to use infcodes.c
* Copyright (C) 1995 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.
*/
struct inflate_codes_state;
typedef struct inflate_codes_state FAR inflate_codes_statef;
local inflate_codes_statef *inflate_codes_new OF((
uInt, uInt,
inflate_huft *, inflate_huft *,
z_stream *));
local int inflate_codes OF((
inflate_blocks_statef *,
z_stream *,
int));
local void inflate_codes_free OF((
inflate_codes_statef *,
z_stream *));
/*+++++*/
/* inflate.c -- zlib interface to inflate modules
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* inflate private state */
struct internal_state {
/* mode */
enum {
METHOD, /* waiting for method byte */
FLAG, /* waiting for flag byte */
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 */
DONE, /* finished check, done */
BAD} /* got an error--stay here */
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 */
};
int inflateReset(z)
z_stream *z;
{
uLong c;
if (z == Z_NULL || z->state == Z_NULL)
return Z_STREAM_ERROR;
z->total_in = z->total_out = 0;
z->msg = Z_NULL;
z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
inflate_blocks_reset(z->state->blocks, z, &c);
Trace((stderr, "inflate: reset\n"));
return Z_OK;
}
int inflateEnd(z)
z_stream *z;
{
uLong c;
if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL)
return Z_STREAM_ERROR;
if (z->state->blocks != Z_NULL)
inflate_blocks_free(z->state->blocks, z, &c);
ZFREE(z, z->state, sizeof(struct internal_state));
z->state = Z_NULL;
Trace((stderr, "inflate: end\n"));
return Z_OK;
}
int inflateInit2(z, w)
z_stream *z;
int w;
{
/* initialize state */
if (z == Z_NULL)
return Z_STREAM_ERROR;
/* if (z->zalloc == Z_NULL) z->zalloc = zcalloc; */
/* if (z->zfree == Z_NULL) z->zfree = zcfree; */
if ((z->state = (struct internal_state FAR *)
ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL)
return Z_MEM_ERROR;
z->state->blocks = Z_NULL;
/* handle undocumented nowrap option (no zlib header or check) */
z->state->nowrap = 0;
if (w < 0)
{
w = - w;
z->state->nowrap = 1;
}
/* set window size */
if (w < 8 || w > 15)
{
inflateEnd(z);
return Z_STREAM_ERROR;
}
z->state->wbits = (uInt)w;
/* create inflate_blocks state */
if ((z->state->blocks =
inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, 1 << w))
== Z_NULL)
{
inflateEnd(z);
return Z_MEM_ERROR;
}
Trace((stderr, "inflate: allocated\n"));
/* reset state */
inflateReset(z);
return Z_OK;
}
int inflateInit(z)
z_stream *z;
{
return inflateInit2(z, DEF_WBITS);
}
#define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;}
#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
int inflate(z, f)
z_stream *z;
int f;
{
int r;
uInt b;
if (z == Z_NULL || z->next_in == Z_NULL)
return Z_STREAM_ERROR;
r = Z_BUF_ERROR;
while (1) switch (z->state->mode)
{
case METHOD:
NEEDBYTE
if (((z->state->sub.method = NEXTBYTE) & 0xf) != DEFLATED)
{
z->state->mode = BAD;
z->msg = "unknown compression method";
z->state->sub.marker = 5; /* can't try inflateSync */
break;
}
if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
{
z->state->mode = BAD;
z->msg = "invalid window size";
z->state->sub.marker = 5; /* can't try inflateSync */
break;
}
z->state->mode = FLAG;
case FLAG:
NEEDBYTE
if ((b = NEXTBYTE) & 0x20)
{
z->state->mode = BAD;
z->msg = "invalid reserved bit";
z->state->sub.marker = 5; /* can't try inflateSync */
break;
}
if (((z->state->sub.method << 8) + b) % 31)
{
z->state->mode = BAD;
z->msg = "incorrect header check";
z->state->sub.marker = 5; /* can't try inflateSync */
break;
}
Trace((stderr, "inflate: zlib header ok\n"));
z->state->mode = BLOCKS;
case BLOCKS:
r = inflate_blocks(z->state->blocks, z, r);
if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
r = inflate_packet_flush(z->state->blocks);
if (r == Z_DATA_ERROR)
{
z->state->mode = BAD;
z->state->sub.marker = 0; /* can try inflateSync */
break;
r = Z_OK;
inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
if (z->state->nowrap)
{
}
z->state->mode = CHECK4;
case CHECK4:
NEEDBYTE
z->state->sub.check.need = (uLong)NEXTBYTE << 24;
z->state->mode = CHECK3;
case CHECK3:
NEEDBYTE
z->state->sub.check.need += (uLong)NEXTBYTE << 16;
z->state->mode = CHECK2;
case CHECK2:
NEEDBYTE
z->state->sub.check.need += (uLong)NEXTBYTE << 8;
z->state->mode = CHECK1;
case CHECK1:
NEEDBYTE
z->state->sub.check.need += (uLong)NEXTBYTE;
if (z->state->sub.check.was != z->state->sub.check.need)
{
z->state->mode = BAD;
z->msg = "incorrect data check";
z->state->sub.marker = 5; /* can't try inflateSync */
break;
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}
Trace((stderr, "inflate: zlib check ok\n"));
z->state->mode = DONE;
case DONE:
return Z_STREAM_END;
case BAD:
return Z_DATA_ERROR;
default:
return Z_STREAM_ERROR;
}
empty:
if (f != Z_PACKET_FLUSH)
return r;
z->state->mode = BAD;
z->state->sub.marker = 0; /* can try inflateSync */
return Z_DATA_ERROR;
}
/*
* 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 inflateIncomp(z)
z_stream *z;
{
if (z->state->mode != BLOCKS)
return Z_DATA_ERROR;
return inflate_addhistory(z->state->blocks, z);
}
int inflateSync(z)
z_stream *z;
{
uInt n; /* number of bytes to look at */
Bytef *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 == Z_NULL || z->state == Z_NULL)
return Z_STREAM_ERROR;
if (z->state->mode != BAD)
{
z->state->mode = 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)
{
if (*p == (Byte)(m < 2 ? 0 : 0xff))
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;
inflateReset(z);
z->total_in = r; z->total_out = w;
z->state->mode = BLOCKS;
return Z_OK;
}
#undef NEEDBYTE
#undef NEXTBYTE
/*+++++*/
/* infutil.h -- types and macros common to blocks and codes
* Copyright (C) 1995 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.
*/
/* inflate blocks semi-private state */
struct inflate_blocks_state {
/* mode */
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 */
DONEB, /* finished last block, done */
BADB} /* got a data error--stuck here */
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) */
uIntf *blens; /* bit lengths of codes */
uInt bb; /* bit length tree depth */
inflate_huft *tb; /* bit length decoding tree */
int nblens; /* # elements allocated at blens */
} trees; /* if DTREE, decoding info for trees */
struct {
inflate_huft *tl, *td; /* trees to free */
inflate_codes_statef
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} 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 */
Bytef *window; /* sliding window */
Bytef *end; /* one byte after sliding window */
Bytef *read; /* window read pointer */
Bytef *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 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 (q<s->read?s->read-q-1:s->end-q)
#define LOADOUT {q=s->write;m=WAVAIL;}
#define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=WAVAIL;}}
#define FLUSH {UPDOUT r=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}
/*
* The IBM 150 firmware munges the data right after _etext[]. This
* protects it. -- Cort
*/
#if 0
local uInt protect_mask[] = {0, 0, 0, 0, 0, 0, 0, 0, 0 ,0 ,0 ,0};
#endif
/* And'ing with mask[n] masks the lower n bits */
local uInt inflate_mask[] = {
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 */
local int inflate_flush OF((
inflate_blocks_statef *,
z_stream *,
int));
/*+++++*/
/* inffast.h -- header to use inffast.c
* Copyright (C) 1995 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.
*/
local int inflate_fast OF((
uInt,
uInt,
inflate_huft *,
inflate_huft *,
inflate_blocks_statef *,
z_stream *));
/*+++++*/
/* infblock.c -- interpret and process block types to last block
* Copyright (C) 1995 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
/* Table for deflate from PKZIP's appnote.txt. */
local 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};
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
/*
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.
*/
local void inflate_blocks_reset(s, z, c)
inflate_blocks_statef *s;
z_stream *z;
uLongf *c;
{
if (s->checkfn != Z_NULL)
*c = s->check;
if (s->mode == BTREE || s->mode == DTREE)
ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt));
if (s->mode == CODES)
{
inflate_codes_free(s->sub.decode.codes, z);
inflate_trees_free(s->sub.decode.td, z);
inflate_trees_free(s->sub.decode.tl, z);
}
s->mode = TYPE;
s->bitk = 0;
s->bitb = 0;
s->read = s->write = s->window;
if (s->checkfn != Z_NULL)
s->check = (*s->checkfn)(0L, Z_NULL, 0);
if (z->outcb != Z_NULL)
(*z->outcb)(Z_NULL, 0);
Trace((stderr, "inflate: blocks reset\n"));
}
local inflate_blocks_statef *inflate_blocks_new(z, c, w)
z_stream *z;
check_func c;
uInt w;
{
inflate_blocks_statef *s;
if ((s = (inflate_blocks_statef *)ZALLOC
(z,1,sizeof(struct inflate_blocks_state))) == Z_NULL)
return s;
if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL)
{
ZFREE(z, s, sizeof(struct inflate_blocks_state));
return Z_NULL;
}
s->end = s->window + w;
s->checkfn = c;
s->mode = TYPE;
Trace((stderr, "inflate: blocks allocated\n"));
inflate_blocks_reset(s, z, &s->check);
return s;
}
local int inflate_blocks(s, z, r)
inflate_blocks_statef *s;
z_stream *z;
int r;
{
uInt t; /* temporary storage */
uLong b; /* bit buffer */
uInt k; /* bits in bit buffer */
Bytef *p; /* input data pointer */
uInt n; /* bytes available there */
Bytef *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)
{
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
case 0: /* stored */
Trace((stderr, "inflate: stored block%s\n",
s->last ? " (last)" : ""));
DUMPBITS(3)
t = k & 7; /* go to byte boundary */
DUMPBITS(t)
s->mode = LENS; /* get length of stored block */
break;
case 1: /* fixed */
Trace((stderr, "inflate: fixed codes block%s\n",
s->last ? " (last)" : ""));
{
uInt bl, bd;
inflate_huft *tl, *td;
inflate_trees_fixed(&bl, &bd, &tl, &td);
s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z);
if (s->sub.decode.codes == Z_NULL)
{
r = Z_MEM_ERROR;
LEAVE
}
s->sub.decode.tl = Z_NULL; /* don't try to free these */
s->sub.decode.td = Z_NULL;
}
DUMPBITS(3)
s->mode = CODES;
break;
case 2: /* dynamic */
Trace((stderr, "inflate: dynamic codes block%s\n",
s->last ? " (last)" : ""));
DUMPBITS(3)
s->mode = TABLE;
break;
case 3: /* illegal */
DUMPBITS(3)
s->mode = BADB;
z->msg = "invalid block type";
r = Z_DATA_ERROR;
LEAVE
}
break;
case LENS:
NEEDBITS(32)
if (((~b) >> 16) != (b & 0xffff))
{
s->mode = BADB;
z->msg = "invalid stored block lengths";
r = Z_DATA_ERROR;
LEAVE
}
s->sub.left = (uInt)b & 0xffff;
b = k = 0; /* dump bits */
Tracev((stderr, "inflate: stored length %u\n", s->sub.left));
s->mode = s->sub.left ? STORED : TYPE;
break;
case STORED:
if (n == 0)
NEEDOUT
t = s->sub.left;
if (t > n) t = n;
if (t > m) t = m;
zmemcpy(q, p, t);
p += t; n -= t;
q += t; m -= t;
if ((s->sub.left -= t) != 0)
Tracev((stderr, "inflate: stored end, %lu total out\n",
z->total_out + (q >= s->read ? q - s->read :
(s->end - s->read) + (q - s->window))));
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 = BADB;
z->msg = "too many length or distance symbols";
r = Z_DATA_ERROR;
LEAVE
}
#endif
t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
if (t < 19)
if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
{
}
s->sub.trees.nblens = t;
DUMPBITS(14)
s->sub.trees.index = 0;
Tracev((stderr, "inflate: table sizes ok\n"));
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)
s->sub.trees.bb = 7;
t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
r = t;
if (r == Z_DATA_ERROR)
s->mode = BADB;
LEAVE
}
s->sub.trees.index = 0;
Tracev((stderr, "inflate: bits tree ok\n"));
s->mode = DTREE;
case DTREE:
while (t = s->sub.trees.table,
s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
inflate_huft *h;
uInt i, j, c;
t = s->sub.trees.bb;
NEEDBITS(t)
h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]);
t = h->word.what.Bits;
c = h->more.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 & 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 = BADB;
z->msg = "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;
}
}
inflate_trees_free(s->sub.trees.tb, z);
s->sub.trees.tb = Z_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 = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f),
s->sub.trees.blens, &bl, &bd, &tl, &td, z);
if (t != Z_OK)
{
if (t == (uInt)Z_DATA_ERROR)
s->mode = BADB;
r = t;