patch-2.4.5 linux/arch/ppc/boot/lib/zlib.c
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- Lines: 2151
- Date:
Thu May 24 15:02:06 2001
- Orig file:
v2.4.4/linux/arch/ppc/boot/lib/zlib.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.4.4/linux/arch/ppc/boot/lib/zlib.c linux/arch/ppc/boot/lib/zlib.c
@@ -0,0 +1,2150 @@
+/*
+ * 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: 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;
+ }
+ 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 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
+ *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 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)
+ {
+ 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)
+ 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 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)
+ 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 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)
+ }
+ 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 ok\n"));
+ 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 ok\n"));
+ if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL)
+ {
+ inflate_trees_free(td, z);
+ inflate_trees_free(tl, z);
+ r = Z_MEM_ERROR;
+ LEAVE
+ }
+ 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 out\n",
+ 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 freed\n"));
+ 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 new\n"));
+ }
+ 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%02x\n", 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 block\n"));
+ 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 %u\n", 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 %u\n", 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 free\n"));
+}
+
+/*+++++*/
+/* 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%02x\n", 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 %u\n", 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 %u\n", 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%02x\n", t->base));
+ *q++ = (Byte)t->base;
+ m--;
+ break;
+ }
+ }
+ else if (e & 32)
+ {
+ Tracevv((stderr, "inflate: * end of block\n"));
+ 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;
+}
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)