zlib.c
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- /*
- * BK Id: SCCS/s.zlib.c 1.8 05/18/01 15:17:24 cort
- */
- /*
- * 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 "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
- /* common constants */
- #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 */
- /* functions */
- #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)
- (*((strm)->zalloc))((strm)->opaque, (items), (size))
- #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: resetn"));
- 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: endn"));
- 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: allocatedn"));
- /* 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 okn"));
- 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;
- }
- if (r != Z_STREAM_END)
- return r;
- r = Z_OK;
- inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
- if (z->state->nowrap)
- {
- z->state->mode = DONE;
- break;
- }
- 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;
- }
- Trace((stderr, "inflate: zlib check okn"));
- 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
- *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 */
- 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
- */
- local uInt protect_mask[] = {0, 0, 0, 0, 0, 0, 0, 0, 0 ,0 ,0 ,0};
- /* 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};
- /*
- 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);
- Trace((stderr, "inflate: blocks resetn"));
- }
- 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 allocatedn"));
- 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)
- {
- case 0: /* stored */
- Trace((stderr, "inflate: stored block%sn",
- 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%sn",
- 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%sn",
- 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 %un", s->sub.left));
- s->mode = s->sub.left ? STORED : TYPE;
- break;
- case STORED:
- if (n == 0)
- LEAVE
- 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)
- break;
- Tracev((stderr, "inflate: stored end, %lu total outn",
- 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)
- t = 19;
- if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL)
- {
- r = Z_MEM_ERROR;
- LEAVE
- }
- s->sub.trees.nblens = t;
- DUMPBITS(14)
- s->sub.trees.index = 0;
- Tracev((stderr, "inflate: table sizes okn"));
- 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 = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb,
- &s->sub.trees.tb, z);
- if (t != Z_OK)
- {
- r = t;
- if (r == Z_DATA_ERROR)
- s->mode = BADB;
- LEAVE
- }
- s->sub.trees.index = 0;
- Tracev((stderr, "inflate: bits tree okn"));
- 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 & 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;
- LEAVE
- }
- Tracev((stderr, "inflate: trees okn"));
- if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
- {
- inflate_trees_free(td, z);
- inflate_trees_free(tl, z);
- r = Z_MEM_ERROR;
- LEAVE
- }
- ZFREE(z, s->sub.trees.blens, s->sub.trees.nblens * sizeof(uInt));
- s->sub.decode.codes = c;
- s->sub.decode.tl = tl;
- s->sub.decode.td = td;
- }
- s->mode = CODES;
- case CODES:
- UPDATE
- if ((r = inflate_codes(s, z, r)) != Z_STREAM_END)
- return inflate_flush(s, z, r);
- r = Z_OK;
- inflate_codes_free(s->sub.decode.codes, z);
- inflate_trees_free(s->sub.decode.td, z);
- inflate_trees_free(s->sub.decode.tl, z);
- LOAD
- Tracev((stderr, "inflate: codes end, %lu total outn",
- z->total_out + (q >= s->read ? q - s->read :
- (s->end - s->read) + (q - s->window))));
- if (!s->last)
- {
- s->mode = TYPE;
- break;
- }
- if (k > 7) /* return unused byte, if any */
- {
- Assert(k < 16, "inflate_codes grabbed too many bytes")
- k -= 8;
- n++;
- p--; /* can always return one */
- }
- s->mode = DRY;
- case DRY:
- FLUSH
- if (s->read != s->write)
- LEAVE
- s->mode = DONEB;
- case DONEB:
- r = Z_STREAM_END;
- LEAVE
- case BADB:
- r = Z_DATA_ERROR;
- LEAVE
- default:
- r = Z_STREAM_ERROR;
- LEAVE
- }
- }
- local int inflate_blocks_free(s, z, c)
- inflate_blocks_statef *s;
- z_stream *z;
- uLongf *c;
- {
- inflate_blocks_reset(s, z, c);
- ZFREE(z, s->window, s->end - s->window);
- ZFREE(z, s, sizeof(struct inflate_blocks_state));
- Trace((stderr, "inflate: blocks freedn"));
- 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.
- */
- local int inflate_addhistory(s, z)
- 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 */
- 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 */
- 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 != Z_NULL)
- s->check = (*s->checkfn)(s->check, q, t);
- zmemcpy(q, p, t);
- q += t;
- p += t;
- n -= t;
- z->total_out += t;
- s->read = q; /* drag read pointer forward */
- /* WRAP */ /* expand WRAP macro by hand to handle s->read */
- if (q == s->end) {
- s->read = q = s->window;
- m = WAVAIL;
- }
- }
- UPDATE
- return Z_OK;
- }
- /*
- * At the end of a Deflate-compressed PPP packet, we expect to have seen
- * a `stored' block type value but not the (zero) length bytes.
- */
- local int inflate_packet_flush(s)
- inflate_blocks_statef *s;
- {
- if (s->mode != LENS)
- return Z_DATA_ERROR;
- s->mode = TYPE;
- return Z_OK;
- }
- /*+++++*/
- /* inftrees.c -- generate Huffman trees for efficient decoding
- * Copyright (C) 1995 Mark Adler
- * For conditions of distribution and use, see copyright notice in zlib.h
- */
- /* simplify the use of the inflate_huft type with some defines */
- #define base more.Base
- #define next more.Next
- #define exop word.what.Exop
- #define bits word.what.Bits
- local int huft_build OF((
- uIntf *, /* code lengths in bits */
- uInt, /* number of codes */
- uInt, /* number of "simple" codes */
- uIntf *, /* list of base values for non-simple codes */
- uIntf *, /* list of extra bits for non-simple codes */
- inflate_huft * FAR*,/* result: starting table */
- uIntf *, /* maximum lookup bits (returns actual) */
- z_stream *)); /* for zalloc function */
- local voidpf falloc OF((
- voidpf, /* opaque pointer (not used) */
- uInt, /* number of items */
- uInt)); /* size of item */
- local void ffree OF((
- voidpf q, /* opaque pointer (not used) */
- voidpf p, /* what to free (not used) */
- uInt n)); /* number of bytes (not used) */
- /* Tables for deflate from PKZIP's appnote.txt. */
- local uInt cplens[] = { /* Copy lengths for literal codes 257..285 */
- 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
- 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
- /* actually lengths - 2; also see note #13 above about 258 */
- local uInt cplext[] = { /* Extra bits for literal codes 257..285 */
- 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
- 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 192, 192}; /* 192==invalid */
- local uInt cpdist[] = { /* Copy offsets for distance codes 0..29 */
- 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
- 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
- 8193, 12289, 16385, 24577};
- local uInt cpdext[] = { /* Extra bits for distance codes */
- 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
- 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
- 12, 12, 13, 13};
- /*
- Huffman code decoding is performed using a multi-level table lookup.
- The fastest way to decode is to simply build a lookup table whose
- size is determined by the longest code. However, the time it takes
- to build this table can also be a factor if the data being decoded
- is not very long. The most common codes are necessarily the
- shortest codes, so those codes dominate the decoding time, and hence
- the speed. The idea is you can have a shorter table that decodes the
- shorter, more probable codes, and then point to subsidiary tables for
- the longer codes. The time it costs to decode the longer codes is
- then traded against the time it takes to make longer tables.
- This results of this trade are in the variables lbits and dbits
- below. lbits is the number of bits the first level table for literal/
- length codes can decode in one step, and dbits is the same thing for
- the distance codes. Subsequent tables are also less than or equal to
- those sizes. These values may be adjusted either when all of the
- codes are shorter than that, in which case the longest code length in
- bits is used, or when the shortest code is *longer* than the requested
- table size, in which case the length of the shortest code in bits is
- used.
- There are two different values for the two tables, since they code a
- different number of possibilities each. The literal/length table
- codes 286 possible values, or in a flat code, a little over eight
- bits. The distance table codes 30 possible values, or a little less
- than five bits, flat. The optimum values for speed end up being
- about one bit more than those, so lbits is 8+1 and dbits is 5+1.
- The optimum values may differ though from machine to machine, and
- possibly even between compilers. Your mileage may vary.
- */
- /* If BMAX needs to be larger than 16, then h and x[] should be uLong. */
- #define BMAX 15 /* maximum bit length of any code */
- #define N_MAX 288 /* maximum number of codes in any set */
- #ifdef DEBUG_ZLIB
- uInt inflate_hufts;
- #endif
- local int huft_build(b, n, s, d, e, t, m, zs)
- uIntf *b; /* code lengths in bits (all assumed <= BMAX) */
- uInt n; /* number of codes (assumed <= N_MAX) */
- uInt s; /* number of simple-valued codes (0..s-1) */
- uIntf *d; /* list of base values for non-simple codes */
- uIntf *e; /* list of extra bits for non-simple codes */
- inflate_huft * FAR *t; /* result: starting table */
- uIntf *m; /* maximum lookup bits, returns actual */
- z_stream *zs; /* for zalloc function */
- /* Given a list of code lengths and a maximum table size, make a set of
- tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR
- if the given code set is incomplete (the tables are still built in this
- case), Z_DATA_ERROR if the input is invalid (all zero length codes or an
- over-subscribed set of lengths), or Z_MEM_ERROR if not enough memory. */
- {
- uInt a; /* counter for codes of length k */
- uInt c[BMAX+1]; /* bit length count table */
- uInt f; /* i repeats in table every f entries */
- int g; /* maximum code length */
- int h; /* table level */
- register uInt i; /* counter, current code */
- register uInt j; /* counter */
- register int k; /* number of bits in current code */
- int l; /* bits per table (returned in m) */
- register uIntf *p; /* pointer into c[], b[], or v[] */
- inflate_huft *q; /* points to current table */
- struct inflate_huft_s r; /* table entry for structure assignment */
- inflate_huft *u[BMAX]; /* table stack */
- uInt v[N_MAX]; /* values in order of bit length */
- register int w; /* bits before this table == (l * h) */
- uInt x[BMAX+1]; /* bit offsets, then code stack */
- uIntf *xp; /* pointer into x */
- int y; /* number of dummy codes added */
- uInt z; /* number of entries in current table */
- /* Generate counts for each bit length */
- p = c;
- #define C0 *p++ = 0;
- #define C2 C0 C0 C0 C0
- #define C4 C2 C2 C2 C2
- C4 /* clear c[]--assume BMAX+1 is 16 */
- p = b; i = n;
- do {
- c[*p++]++; /* assume all entries <= BMAX */
- } while (--i);
- if (c[0] == n) /* null input--all zero length codes */
- {
- *t = (inflate_huft *)Z_NULL;
- *m = 0;
- return Z_OK;
- }
- /* Find minimum and maximum length, bound *m by those */
- l = *m;
- for (j = 1; j <= BMAX; j++)
- if (c[j])
- break;
- k = j; /* minimum code length */
- if ((uInt)l < j)
- l = j;
- for (i = BMAX; i; i--)
- if (c[i])
- break;
- g = i; /* maximum code length */
- if ((uInt)l > i)
- l = i;
- *m = l;
- /* Adjust last length count to fill out codes, if needed */
- for (y = 1 << j; j < i; j++, y <<= 1)
- if ((y -= c[j]) < 0)
- return Z_DATA_ERROR;
- if ((y -= c[i]) < 0)
- return Z_DATA_ERROR;
- c[i] += y;
- /* Generate starting offsets into the value table for each length */
- x[1] = j = 0;
- p = c + 1; xp = x + 2;
- while (--i) { /* note that i == g from above */
- *xp++ = (j += *p++);
- }
- /* Make a table of values in order of bit lengths */
- p = b; i = 0;
- do {
- if ((j = *p++) != 0)
- v[x[j]++] = i;
- } while (++i < n);
- /* Generate the Huffman codes and for each, make the table entries */
- x[0] = i = 0; /* first Huffman code is zero */
- p = v; /* grab values in bit order */
- h = -1; /* no tables yet--level -1 */
- w = -l; /* bits decoded == (l * h) */
- u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */
- q = (inflate_huft *)Z_NULL; /* ditto */
- z = 0; /* ditto */
- /* go through the bit lengths (k already is bits in shortest code) */
- for (; k <= g; k++)
- {
- a = c[k];
- while (a--)
- {
- /* here i is the Huffman code of length k bits for value *p */
- /* make tables up to required level */
- while (k > w + l)
- {
- h++;
- w += l; /* previous table always l bits */
- /* compute minimum size table less than or equal to l bits */
- z = (z = g - w) > (uInt)l ? l : z; /* table size upper limit */
- if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
- { /* too few codes for k-w bit table */
- f -= a + 1; /* deduct codes from patterns left */
- xp = c + k;
- if (j < z)
- while (++j < z) /* try smaller tables up to z bits */
- {
- if ((f <<= 1) <= *++xp)
- break; /* enough codes to use up j bits */
- f -= *xp; /* else deduct codes from patterns */
- }
- }
- z = 1 << j; /* table entries for j-bit table */
- /* allocate and link in new table */
- if ((q = (inflate_huft *)ZALLOC
- (zs,z + 1,sizeof(inflate_huft))) == Z_NULL)
- {
- if (h)
- inflate_trees_free(u[0], zs);
- return Z_MEM_ERROR; /* not enough memory */
- }
- q->word.Nalloc = z + 1;
- #ifdef DEBUG_ZLIB
- inflate_hufts += z + 1;
- #endif
- *t = q + 1; /* link to list for huft_free() */
- *(t = &(q->next)) = Z_NULL;
- u[h] = ++q; /* table starts after link */
- /* connect to last table, if there is one */
- if (h)
- {
- x[h] = i; /* save pattern for backing up */
- r.bits = (Byte)l; /* bits to dump before this table */
- r.exop = (Byte)j; /* bits in this table */
- r.next = q; /* pointer to this table */
- j = i >> (w - l); /* (get around Turbo C bug) */
- u[h-1][j] = r; /* connect to last table */
- }
- }
- /* set up table entry in r */
- r.bits = (Byte)(k - w);
- if (p >= v + n)
- r.exop = 128 + 64; /* out of values--invalid code */
- else if (*p < s)
- {
- r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */
- r.base = *p++; /* simple code is just the value */
- }
- else
- {
- r.exop = (Byte)e[*p - s] + 16 + 64; /* non-simple--look up in lists */
- r.base = d[*p++ - s];
- }
- /* fill code-like entries with r */
- f = 1 << (k - w);
- for (j = i >> w; j < z; j += f)
- q[j] = r;
- /* backwards increment the k-bit code i */
- for (j = 1 << (k - 1); i & j; j >>= 1)
- i ^= j;
- i ^= j;
- /* backup over finished tables */
- while ((i & ((1 << w) - 1)) != x[h])
- {
- h--; /* don't need to update q */
- w -= l;
- }
- }
- }
- /* Return Z_BUF_ERROR if we were given an incomplete table */
- return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
- }
- local int inflate_trees_bits(c, bb, tb, z)
- uIntf *c; /* 19 code lengths */
- uIntf *bb; /* bits tree desired/actual depth */
- inflate_huft * FAR *tb; /* bits tree result */
- z_stream *z; /* for zfree function */
- {
- int r;
- r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z);
- if (r == Z_DATA_ERROR)
- z->msg = "oversubscribed dynamic bit lengths tree";
- else if (r == Z_BUF_ERROR)
- {
- inflate_trees_free(*tb, z);
- z->msg = "incomplete dynamic bit lengths tree";
- r = Z_DATA_ERROR;
- }
- return r;
- }
- local int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z)
- uInt nl; /* number of literal/length codes */
- uInt nd; /* number of distance codes */
- uIntf *c; /* that many (total) code lengths */
- uIntf *bl; /* literal desired/actual bit depth */
- uIntf *bd; /* distance desired/actual bit depth */
- inflate_huft * FAR *tl; /* literal/length tree result */
- inflate_huft * FAR *td; /* distance tree result */
- z_stream *z; /* for zfree function */
- {
- int r;
- /* build literal/length tree */
- if ((r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z)) != Z_OK)
- {
- if (r == Z_DATA_ERROR)
- z->msg = "oversubscribed literal/length tree";
- else if (r == Z_BUF_ERROR)
- {
- inflate_trees_free(*tl, z);
- z->msg = "incomplete literal/length tree";
- r = Z_DATA_ERROR;
- }
- return r;
- }
- /* build distance tree */
- if ((r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z)) != Z_OK)
- {
- if (r == Z_DATA_ERROR)
- z->msg = "oversubscribed literal/length tree";
- else if (r == Z_BUF_ERROR) {
- #ifdef PKZIP_BUG_WORKAROUND
- r = Z_OK;
- }
- #else
- inflate_trees_free(*td, z);
- z->msg = "incomplete literal/length tree";
- r = Z_DATA_ERROR;
- }
- inflate_trees_free(*tl, z);
- return r;
- #endif
- }
- /* done */
- return Z_OK;
- }
- /* build fixed tables only once--keep them here */
- local int fixed_lock = 0;
- local int fixed_built = 0;
- #define FIXEDH 530 /* number of hufts used by fixed tables */
- local uInt fixed_left = FIXEDH;
- local inflate_huft fixed_mem[FIXEDH];
- local uInt fixed_bl;
- local uInt fixed_bd;
- local inflate_huft *fixed_tl;
- local inflate_huft *fixed_td;
- local voidpf falloc(q, n, s)
- voidpf q; /* opaque pointer (not used) */
- uInt n; /* number of items */
- uInt s; /* size of item */
- {
- Assert(s == sizeof(inflate_huft) && n <= fixed_left,
- "inflate_trees falloc overflow");
- if (q) s++; /* to make some compilers happy */
- fixed_left -= n;
- return (voidpf)(fixed_mem + fixed_left);
- }
- local void ffree(q, p, n)
- voidpf q;
- voidpf p;
- uInt n;
- {
- Assert(0, "inflate_trees ffree called!");
- if (q) q = p; /* to make some compilers happy */
- }
- local int inflate_trees_fixed(bl, bd, tl, td)
- uIntf *bl; /* literal desired/actual bit depth */
- uIntf *bd; /* distance desired/actual bit depth */
- inflate_huft * FAR *tl; /* literal/length tree result */
- inflate_huft * FAR *td; /* distance tree result */
- {
- /* build fixed tables if not built already--lock out other instances */
- while (++fixed_lock > 1)
- fixed_lock--;
- if (!fixed_built)
- {
- int k; /* temporary variable */
- unsigned c[288]; /* length list for huft_build */
- z_stream z; /* for falloc function */
- /* set up fake z_stream for memory routines */
- z.zalloc = falloc;
- z.zfree = ffree;
- z.opaque = Z_NULL;
- /* literal table */
- for (k = 0; k < 144; k++)
- c[k] = 8;
- for (; k < 256; k++)
- c[k] = 9;
- for (; k < 280; k++)
- c[k] = 7;
- for (; k < 288; k++)
- c[k] = 8;
- fixed_bl = 7;
- huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z);
- /* distance table */
- for (k = 0; k < 30; k++)
- c[k] = 5;
- fixed_bd = 5;
- huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z);
- /* done */
- fixed_built = 1;
- }
- fixed_lock--;
- *bl = fixed_bl;
- *bd = fixed_bd;
- *tl = fixed_tl;
- *td = fixed_td;
- return Z_OK;
- }
- local int inflate_trees_free(t, z)
- inflate_huft *t; /* table to free */
- z_stream *z; /* for zfree function */
- /* Free the malloc'ed tables built by huft_build(), which makes a linked
- list of the tables it made, with the links in a dummy first entry of
- each table. */
- {
- register inflate_huft *p, *q;
- /* Go through linked list, freeing from the malloced (t[-1]) address. */
- p = t;
- while (p != Z_NULL)
- {
- q = (--p)->next;
- ZFREE(z, p, p->word.Nalloc * sizeof(inflate_huft));
- p = q;
- }
- return Z_OK;
- }
- /*+++++*/
- /* infcodes.c -- process literals and length/distance pairs
- * Copyright (C) 1995 Mark Adler
- * For conditions of distribution and use, see copyright notice in zlib.h
- */
- /* simplify the use of the inflate_huft type with some defines */
- #define base more.Base
- #define next more.Next
- #define exop word.what.Exop
- #define bits word.what.Bits
- /* inflate codes private state */
- struct inflate_codes_state {
- /* mode */
- enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
- 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 */
- 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 */
- };
- local inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z)
- uInt bl, bd;
- inflate_huft *tl, *td;
- z_stream *z;
- {
- inflate_codes_statef *c;
- if ((c = (inflate_codes_statef *)
- ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
- {
- c->mode = START;
- c->lbits = (Byte)bl;
- c->dbits = (Byte)bd;
- c->ltree = tl;
- c->dtree = td;
- Tracev((stderr, "inflate: codes newn"));
- }
- return c;
- }
- local int inflate_codes(s, z, r)
- inflate_blocks_statef *s;
- z_stream *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 */
- 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 */
- Bytef *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 = 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 & inflate_mask[j]);
- DUMPBITS(t->bits)
- e = (uInt)(t->exop);
- if (e == 0) /* literal */
- {
- c->sub.lit = t->base;
- Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
- "inflate: literal '%c'n" :
- "inflate: literal 0x%02xn", 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->next;
- break;
- }
- if (e & 32) /* end of block */
- {
- Tracevv((stderr, "inflate: end of blockn"));
- c->mode = WASH;
- break;
- }
- c->mode = BADCODE; /* invalid code */
- z->msg = "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 & inflate_mask[j];
- DUMPBITS(j)
- c->sub.code.need = c->dbits;
- c->sub.code.tree = c->dtree;
- Tracevv((stderr, "inflate: length %un", c->len));
- c->mode = DIST;
- case DIST: /* i: get distance next */
- j = c->sub.code.need;
- NEEDBITS(j)
- t = c->sub.code.tree + ((uInt)b & 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->next;
- break;
- }
- c->mode = BADCODE; /* invalid code */
- z->msg = "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 & inflate_mask[j];
- DUMPBITS(j)
- Tracevv((stderr, "inflate: distance %un", c->sub.copy.dist));
- c->mode = COPY;
- case COPY: /* o: copying bytes in window, waiting for space */
- #ifndef __TURBOC__ /* Turbo C bug for following expression */
- f = (uInt)(q - s->window) < c->sub.copy.dist ?
- s->end - (c->sub.copy.dist - (q - s->window)) :
- q - c->sub.copy.dist;
- #else
- f = q - c->sub.copy.dist;
- if ((uInt)(q - s->window) < c->sub.copy.dist)
- f = s->end - (c->sub.copy.dist - (q - s->window));
- #endif
- 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 */
- 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
- }
- }
- local void inflate_codes_free(c, z)
- inflate_codes_statef *c;
- z_stream *z;
- {
- ZFREE(z, c, sizeof(struct inflate_codes_state));
- Tracev((stderr, "inflate: codes freen"));
- }
- /*+++++*/
- /* inflate_util.c -- data and routines common to blocks and codes
- * Copyright (C) 1995 Mark Adler
- * For conditions of distribution and use, see copyright notice in zlib.h
- */
- /* copy as much as possible from the sliding window to the output area */
- local int inflate_flush(s, z, r)
- inflate_blocks_statef *s;
- z_stream *z;
- int r;
- {
- uInt n;
- Bytef *p, *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 != Z_NULL)
- s->check = (*s->checkfn)(s->check, q, n);
- /* copy as far as end of window */
- zmemcpy(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 != Z_NULL)
- s->check = (*s->checkfn)(s->check, q, n);
- /* copy */
- zmemcpy(p, q, n);
- p += n;
- q += n;
- }
- /* update pointers */
- z->next_out = p;
- s->read = q;
- /* done */
- return r;
- }
- /*+++++*/
- /* inffast.c -- process literals and length/distance pairs fast
- * Copyright (C) 1995 Mark Adler
- * For conditions of distribution and use, see copyright notice in zlib.h
- */
- /* simplify the use of the inflate_huft type with some defines */
- #define base more.Base
- #define next more.Next
- #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 {n+=(c=k>>3);p-=c;k&=7;}
- /* 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. */
- local int inflate_fast(bl, bd, tl, td, s, z)
- uInt bl, bd;
- inflate_huft *tl, *td;
- inflate_blocks_statef *s;
- z_stream *z;
- {
- inflate_huft *t; /* temporary pointer */
- uInt e; /* extra bits or operation */
- 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 */
- 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 */
- Bytef *r; /* copy source pointer */
- /* load input, output, bit values */
- LOAD
- /* initialize masks */
- ml = inflate_mask[bl];
- md = 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)
- Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
- "inflate: * literal '%c'n" :
- "inflate: * literal 0x%02xn", t->base));
- *q++ = (Byte)t->base;
- m--;
- continue;
- }
- do {
- DUMPBITS(t->bits)
- if (e & 16)
- {
- /* get extra bits for length */
- e &= 15;
- c = t->base + ((uInt)b & inflate_mask[e]);
- DUMPBITS(e)
- Tracevv((stderr, "inflate: * length %un", c));
- /* 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 & inflate_mask[e]);
- DUMPBITS(e)
- Tracevv((stderr, "inflate: * distance %un", d));
- /* do the copy */
- m -= c;
- if ((uInt)(q - s->window) >= d) /* offset before dest */
- { /* just copy */
- r = q - d;
- *q++ = *r++; c--; /* minimum count is three, */
- *q++ = *r++; c--; /* so unroll loop a little */
- }
- else /* else offset after destination */
- {
- e = d - (q - s->window); /* bytes from offset to end */
- r = s->end - e; /* pointer to offset */
- if (c > e) /* if source crosses, */
- {
- c -= e; /* copy to end of window */
- do {
- *q++ = *r++;
- } while (--e);
- r = s->window; /* copy rest from start of window */
- }
- }
- do { /* copy all or what's left */
- *q++ = *r++;
- } while (--c);
- break;
- }
- else if ((e & 64) == 0)
- e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop;
- else
- {
- z->msg = "invalid distance code";
- UNGRAB
- UPDATE
- return Z_DATA_ERROR;
- }
- } while (1);
- break;
- }
- if ((e & 64) == 0)
- {
- if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0)
- {
- DUMPBITS(t->bits)
- Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ?
- "inflate: * literal '%c'n" :
- "inflate: * literal 0x%02xn", t->base));
- *q++ = (Byte)t->base;
- m--;
- break;
- }
- }
- else if (e & 32)
- {
- Tracevv((stderr, "inflate: * end of blockn"));
- UNGRAB
- UPDATE
- return Z_STREAM_END;
- }
- else
- {
- z->msg = "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;
- }
- /*+++++*/
- /* zutil.c -- target dependent utility functions for the compression library
- * Copyright (C) 1995 Jean-loup Gailly.
- * For conditions of distribution and use, see copyright notice in zlib.h
- */
- /* From: zutil.c,v 1.8 1995/05/03 17:27:12 jloup Exp */
- char *zlib_version = ZLIB_VERSION;
- char *z_errmsg[] = {
- "stream end", /* Z_STREAM_END 1 */
- "", /* Z_OK 0 */
- "file error", /* Z_ERRNO (-1) */
- "stream error", /* Z_STREAM_ERROR (-2) */
- "data error", /* Z_DATA_ERROR (-3) */
- "insufficient memory", /* Z_MEM_ERROR (-4) */
- "buffer error", /* Z_BUF_ERROR (-5) */
- ""};
- /*+++++*/
- /* adler32.c -- compute the Adler-32 checksum of a data stream
- * Copyright (C) 1995 Mark Adler
- * For conditions of distribution and use, see copyright notice in zlib.h
- */
- /* From: adler32.c,v 1.6 1995/05/03 17:27:08 jloup Exp */
- #define BASE 65521L /* largest prime smaller than 65536 */
- #define NMAX 5552
- /* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */
- #define DO1(buf) {s1 += *buf++; s2 += s1;}
- #define DO2(buf) DO1(buf); DO1(buf);
- #define DO4(buf) DO2(buf); DO2(buf);
- #define DO8(buf) DO4(buf); DO4(buf);
- #define DO16(buf) DO8(buf); DO8(buf);
- /* ========================================================================= */
- uLong adler32(adler, buf, len)
- uLong adler;
- Bytef *buf;
- uInt len;
- {
- unsigned long s1 = adler & 0xffff;
- unsigned long s2 = (adler >> 16) & 0xffff;
- int k;
- if (buf == Z_NULL) return 1L;
- while (len > 0) {
- k = len < NMAX ? len : NMAX;
- len -= k;
- while (k >= 16) {
- DO16(buf);
- k -= 16;
- }
- if (k != 0) do {
- DO1(buf);
- } while (--k);
- s1 %= BASE;
- s2 %= BASE;
- }
- return (s2 << 16) | s1;
- }