1434 lines
46 KiB
C
1434 lines
46 KiB
C
/*
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* Copyright (c) 1995 Matthias Pfaller.
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*
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* Most of this code is from the unzip512 distribution and was put
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* in the public domain by Mark Adler 1994.
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*
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by Matthias Pfaller.
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* 4. The name of the author may not be used to endorse or promote products
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* derived from this software without specific prior written permission
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* $Id: inflate.c,v 1.2 1995/09/26 20:16:38 phil Exp $
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*/
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#include <sys/param.h>
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#include <sys/reboot.h>
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#include <a.out.h>
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#include "stand.h"
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#include "samachdep.h"
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#ifndef EOF
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#define EOF -1
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#endif
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typedef unsigned char uch; /* code assumes unsigned bytes; these type- */
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typedef unsigned short ush; /* defs replace byte/UWORD/ULONG (which are */
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typedef unsigned long ulg; /* predefined on some systems) & match zip */
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extern int qflag;
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extern uch slide[];
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extern ulg crc_32_tab[];
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#define NEXTBYTE nextbyte()
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#define FLUSH(n) flush(n)
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#define WSIZE 0x8000
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#define memzero(dest, len) bzero(dest, len)
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/* Function prototypes */
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#ifndef OF
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# ifdef __STDC__
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# define OF(a) a
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# else /* !__STDC__ */
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# define OF(a) ()
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# endif /* ?__STDC__ */
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#endif
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/* From: funzip.c -- put in the public domain by Mark Adler */
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#define VERSION "3.83 of 28 August 1994"
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/*
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All funzip does is take a zip file from stdin and decompress the
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first entry to stdout. The entry has to be either deflated or
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stored. If the entry is encrypted, then the decryption password
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must be supplied on the command line as the first argument.
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funzip needs to be linked with inflate.o and crypt.o compiled from
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the unzip source. If decryption is desired, the full version of
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crypt.c (and crypt.h) from zcrypt21.zip or later must be used.
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*/
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/* compression methods */
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#define STORED 0
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#define DEFLATED 8
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/* PKZIP header definitions */
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#define ZIPMAG 0x4b50 /* two-byte zip lead-in */
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#define LOCREM 0x0403 /* remaining two bytes in zip signature */
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#define LOCSIG 0x04034b50L /* full signature */
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#define LOCFLG 4 /* offset of bit flag */
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#define CRPFLG 1 /* bit for encrypted entry */
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#define EXTFLG 8 /* bit for extended local header */
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#define LOCHOW 6 /* offset of compression method */
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#define LOCTIM 8 /* file mod time (for decryption) */
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#define LOCCRC 12 /* offset of crc */
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#define LOCSIZ 16 /* offset of compressed size */
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#define LOCLEN 20 /* offset of uncompressed length */
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#define LOCFIL 24 /* offset of file name field length */
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#define LOCEXT 26 /* offset of extra field length */
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#define LOCHDR 28 /* size of local header, including LOCREM */
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#define EXTHDR 16 /* size of extended local header, inc sig */
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/* GZIP header definitions */
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#define GZPMAG 0x8b1f /* two-byte gzip lead-in */
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#define GZPHOW 0 /* offset of method number */
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#define GZPFLG 1 /* offset of gzip flags */
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#define GZPMUL 2 /* bit for multiple-part gzip file */
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#define GZPISX 4 /* bit for extra field present */
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#define GZPISF 8 /* bit for filename present */
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#define GZPISC 16 /* bit for comment present */
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#define GZPISE 32 /* bit for encryption */
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#define GZPTIM 2 /* offset of Unix file modification time */
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#define GZPEXF 6 /* offset of extra flags */
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#define GZPCOS 7 /* offset of operating system compressed on */
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#define GZPHDR 8 /* length of minimal gzip header */
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/* Macros for getting two-byte and four-byte header values */
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#define SH(p) ((ush)(uch)((p)[0]) | ((ush)(uch)((p)[1]) << 8))
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#define LG(p) ((ulg)(SH(p)) | ((ulg)(SH((p)+2)) << 16))
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/* Function prototypes */
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ulg updcrc OF((uch *, ulg));
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int inflate OF((void));
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void err OF((int, char *));
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/* Globals */
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uch *outptr; /* points to next byte in output buffer */
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ulg outcnt; /* bytes in output buffer */
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ulg outsiz; /* total bytes written to out */
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int encrypted; /* flag to turn on decryption */
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int qflag = 1; /* turn off messages in inflate.c */
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uch slide[WSIZE];
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uch *addr, *load, *esym;
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extern uch *r3, *r6, *r7;
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int bsize;
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/* Masks for inflate.c */
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ush mask_bits[] = {
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0x0000,
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0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
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0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
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};
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extern uch input_data[];
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uch *datap = input_data;
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struct exec x;
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int nextbyte()
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{
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extern int input_len;
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if (!(input_len & 0x1fff))
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twiddle();
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if (input_len-- > 0)
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return(*datap++);
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else
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return(EOF);
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}
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int nextblock(p, n)
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char *p;
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int n;
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{
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extern int input_len;
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twiddle();
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if (input_len < n)
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return(0);
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memcpy(p, datap, n);
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input_len -= n;
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datap += n;
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return(n);
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}
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ulg updcrc(s, n)
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uch *s; /* pointer to bytes to pump through */
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ulg n; /* number of bytes in s[] */
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/* Run a set of bytes through the crc shift register. If s is a NULL
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pointer, then initialize the crc shift register contents instead.
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Return the current crc in either case. */
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{
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register ulg c; /* temporary variable */
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static ulg crc = 0xffffffffL; /* shift register contents */
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if (s == (uch *)NULL)
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c = 0xffffffffL;
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else
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{
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c = crc;
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while (n--)
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c = crc_32_tab[((int)c ^ (*s++)) & 0xff] ^ (c >> 8);
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}
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crc = c;
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return c ^ 0xffffffffL; /* (instead of ~c for 64-bit machines) */
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}
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void nextstate()
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{
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static int state = 0;
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switch (state) {
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case 0:
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if (N_BADMAG(x))
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panic("Bad exec format\n");
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load = addr = (uch *)(x.a_entry & 0x00ffff00);
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printf("Uncompressing @ 0x%x\n", addr);
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bsize = x.a_text;
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if (N_GETMAGIC(x) == ZMAGIC) {
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bcopy(&x, addr, sizeof(x));
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addr += sizeof(x);
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bsize -= sizeof(x);
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}
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printf("%d", x.a_text);
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state = 1;
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break;
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case 1:
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if (N_GETMAGIC(x) == NMAGIC)
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while ((int)addr & CLOFSET)
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*addr++ = 0;
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bsize = x.a_data;
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printf("+%d", x.a_data);
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state = 2;
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break;
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case 2:
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printf("+%d", x.a_bss);
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bzero(addr, x.a_bss );
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addr += x.a_bss;
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bcopy(&x.a_syms, addr, sizeof(x.a_syms));
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addr += sizeof(x.a_syms);
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printf(" [%d+", x.a_syms);
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if (x.a_syms) {
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bsize = x.a_syms + sizeof(int);
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state = 3;
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break;
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}
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printf("0]");
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case 4:
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printf(" total 0x%x", addr);
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x.a_entry &= 0xffffff;
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printf(" start 0x%x\n", x.a_entry);
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#define round_to_size(x,t) \
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(((int)(x) + sizeof(t) - 1) & ~(sizeof(t) - 1))
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esym = (char *)round_to_size(addr - load, int);
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#undef round_to_size
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state = -1;
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break;
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case 3:
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printf("%d]", ((int *)addr)[-1]);
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bsize = ((int *)addr)[-1] - sizeof(int);
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state = 4;
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break;
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case -1:
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printf("Already at EOF\n");
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break;
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}
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}
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int flush(w) /* used by inflate.c (FLUSH macro) */
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ulg w; /* number of bytes to flush */
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{
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uch *p = slide;
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updcrc(slide, w);
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outsiz += w;
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while (bsize <= w) {
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bcopy(p, addr, bsize);
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p += bsize;
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addr += bsize;
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w -= bsize;
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nextstate();
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}
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if (w) {
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bcopy(p, addr, w);
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addr += w;
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bsize -= w;
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}
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return(0);
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}
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main()
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{
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ush n;
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uch h[LOCHDR]; /* first local header (GZPHDR < LOCHDR) */
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int g = 0; /* true if gzip format */
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char *s = "";
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cninit();
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addr = (uch *)&x;
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bsize = sizeof(x);
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/* read local header, check validity, and skip name and extra fields */
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n = nextbyte(); n |= nextbyte() << 8;
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if (n == ZIPMAG)
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{
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if (nextblock((char *)h, LOCHDR) != LOCHDR || SH(h) != LOCREM)
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panic("invalid zip file");
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if (SH(h + LOCHOW) != STORED && SH(h + LOCHOW) != DEFLATED)
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panic("first entry not deflated or stored--can't funzip");
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for (n = SH(h + LOCFIL); n--; ) g = nextbyte();
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for (n = SH(h + LOCEXT); n--; ) g = nextbyte();
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g = 0;
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encrypted = h[LOCFLG] & CRPFLG;
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}
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else if (n == GZPMAG)
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{
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if (nextblock((char *)h, GZPHDR) != GZPHDR)
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panic("invalid gzip file");
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if (h[GZPHOW] != DEFLATED)
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panic("gzip file not deflated");
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if (h[GZPFLG] & GZPMUL)
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panic("cannot handle multi-part gzip files");
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if (h[GZPFLG] & GZPISX)
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{
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n = nextbyte(); n |= nextbyte() << 8;
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while (n--) g = nextbyte();
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}
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if (h[GZPFLG] & GZPISF)
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while ((g = nextbyte()) != 0 && g != EOF) ;
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if (h[GZPFLG] & GZPISC)
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while ((g = nextbyte()) != 0 && g != EOF) ;
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g = 1;
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encrypted = h[GZPFLG] & GZPISE;
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}
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else
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panic("input not a zip or gzip file");
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/* if entry encrypted, decrypt and validate encryption header */
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if (encrypted)
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panic("cannot decrypt entry (need to recompile with full crypt.c)");
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/* prepare output buffer and crc */
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outptr = slide;
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outcnt = 0L;
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outsiz = 0L;
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updcrc(NULL, 0L);
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/* decompress */
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if (g || h[LOCHOW])
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{ /* deflated entry */
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int r;
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if ((r = inflate()) != 0)
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if (r == 3)
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panic("out of memory");
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else
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panic("invalid compressed data--format violated");
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inflate_free();
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}
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else
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{ /* stored entry */
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register ulg n;
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n = LG(h + LOCLEN);
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if (n != LG(h + LOCSIZ)) {
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printf("len %ld, siz %ld\n", n, LG(h + LOCSIZ));
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panic("invalid compressed data--length mismatch");
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}
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while (n--) {
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ush c = nextbyte();
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*outptr++ = (uch)c;
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if (++outcnt == WSIZE) /* do FlushOutput() */
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{
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flush(outcnt);
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outptr = slide;
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outcnt = 0L;
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}
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}
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if (outcnt) /* flush one last time; no need to reset outptr/outcnt */
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flush(outcnt);
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}
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/* if extended header, get it */
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if (g)
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{
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if (nextblock((char *)h + LOCCRC, 8) != 8)
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panic("gzip file ended prematurely");
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}
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else
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if ((h[LOCFLG] & EXTFLG) &&
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nextblock((char *)h + LOCCRC - 4, EXTHDR) != EXTHDR)
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panic("zip file ended prematurely");
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/* validate decompression */
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if (LG(h + LOCCRC) != updcrc(slide, 0L))
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panic("invalid compressed data--crc error");
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if (LG(h + (g ? LOCSIZ : LOCLEN)) != outsiz)
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panic("invalid compressed data--length error");
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/* check if there are more entries */
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if (!g && nextblock((char *)h, 4) == 4 && LG(h) == LOCSIG)
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printf("funzip warning: zip file has more than one entry--rest ignored\n");
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asm(" movd %0,r3" : : "g" (r3)); /* magic */
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asm(" movd %0,r4" : : "g" (esym));
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asm(" movd %0,r5" : : "g" (load));
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asm(" movd %0,r6" : : "g" (r6)); /* devtype */
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asm(" movd %0,r7" : : "g" (r7)); /* howto */
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(*((int (*)()) x.a_entry))();
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}
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/* Table of CRC-32's of all single-byte values (made by makecrc.c) */
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ulg crc_32_tab[] = {
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0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
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0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
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0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
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0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
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0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
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0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
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0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
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0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
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0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
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0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
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0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
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0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
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0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
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0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
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0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
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0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
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0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
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0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
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0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
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0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
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0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
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0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
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0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
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0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
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0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
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0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
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0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
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0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
|
|
0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
|
|
0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
|
|
0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
|
|
0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
|
|
0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
|
|
0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
|
|
0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
|
|
0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
|
|
0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
|
|
0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
|
|
0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
|
|
0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
|
|
0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
|
|
0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
|
|
0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
|
|
0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
|
|
0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
|
|
0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
|
|
0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
|
|
0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
|
|
0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
|
|
0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
|
|
0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
|
|
0x2d02ef8dL
|
|
};
|
|
|
|
/* From: inflate.c -- put in the public domain by Mark Adler
|
|
version c14o, 23 August 1994 */
|
|
|
|
/*
|
|
Inflate deflated (PKZIP's method 8 compressed) data. The compression
|
|
method searches for as much of the current string of bytes (up to a
|
|
length of 258) in the previous 32K bytes. If it doesn't find any
|
|
matches (of at least length 3), it codes the next byte. Otherwise, it
|
|
codes the length of the matched string and its distance backwards from
|
|
the current position. There is a single Huffman code that codes both
|
|
single bytes (called "literals") and match lengths. A second Huffman
|
|
code codes the distance information, which follows a length code. Each
|
|
length or distance code actually represents a base value and a number
|
|
of "extra" (sometimes zero) bits to get to add to the base value. At
|
|
the end of each deflated block is a special end-of-block (EOB) literal/
|
|
length code. The decoding process is basically: get a literal/length
|
|
code; if EOB then done; if a literal, emit the decoded byte; if a
|
|
length then get the distance and emit the referred-to bytes from the
|
|
sliding window of previously emitted data.
|
|
|
|
There are (currently) three kinds of inflate blocks: stored, fixed, and
|
|
dynamic. The compressor outputs a chunk of data at a time and decides
|
|
which method to use on a chunk-by-chunk basis. A chunk might typically
|
|
be 32K to 64K, uncompressed. If the chunk is uncompressible, then the
|
|
"stored" method is used. In this case, the bytes are simply stored as
|
|
is, eight bits per byte, with none of the above coding. The bytes are
|
|
preceded by a count, since there is no longer an EOB code.
|
|
|
|
If the data is compressible, then either the fixed or dynamic methods
|
|
are used. In the dynamic method, the compressed data is preceded by
|
|
an encoding of the literal/length and distance Huffman codes that are
|
|
to be used to decode this block. The representation is itself Huffman
|
|
coded, and so is preceded by a description of that code. These code
|
|
descriptions take up a little space, and so for small blocks, there is
|
|
a predefined set of codes, called the fixed codes. The fixed method is
|
|
used if the block ends up smaller that way (usually for quite small
|
|
chunks); otherwise the dynamic method is used. In the latter case, the
|
|
codes are customized to the probabilities in the current block and so
|
|
can code it much better than the pre-determined fixed codes can.
|
|
|
|
The Huffman codes themselves are decoded using a mutli-level table
|
|
lookup, in order to maximize the speed of decoding plus the speed of
|
|
building the decoding tables. See the comments below that precede the
|
|
lbits and dbits tuning parameters.
|
|
*/
|
|
|
|
|
|
/*
|
|
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.
|
|
*/
|
|
|
|
|
|
#define PKZIP_BUG_WORKAROUND /* PKZIP 1.93a problem--live with it */
|
|
|
|
/*
|
|
inflate.h must supply the uch slide[WSIZE] array and the NEXTBYTE,
|
|
FLUSH() and memzero macros. If the window size is not 32K, it
|
|
should also define WSIZE. If INFMOD is defined, it can include
|
|
compiled functions to support the NEXTBYTE and/or FLUSH() macros.
|
|
There are defaults for NEXTBYTE and FLUSH() below for use as
|
|
examples of what those functions need to do. Normally, you would
|
|
also want FLUSH() to compute a crc on the data. inflate.h also
|
|
needs to provide these typedefs:
|
|
|
|
typedef unsigned char uch;
|
|
typedef unsigned short ush;
|
|
typedef unsigned long ulg;
|
|
|
|
This module uses the external functions malloc() and free() (and
|
|
probably memset() or bzero() in the memzero() macro). Their
|
|
prototypes are normally found in <string.h> and <stdlib.h>.
|
|
*/
|
|
|
|
/* Warning: the fwrite above might not work on 16-bit compilers, since
|
|
0x8000 might be interpreted as -32,768 by the library function. */
|
|
|
|
/* 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).
|
|
Valid extra bits are 0..13. e == 15 is EOB (end of block), e == 16
|
|
means that v is a literal, 16 < e < 32 means that v is a pointer to
|
|
the next table, which codes e - 16 bits, and lastly e == 99 indicates
|
|
an unused code. If a code with e == 99 is looked up, this implies an
|
|
error in the data. */
|
|
struct huft {
|
|
uch e; /* number of extra bits or operation */
|
|
uch b; /* number of bits in this code or subcode */
|
|
union {
|
|
ush n; /* literal, length base, or distance base */
|
|
struct huft *t; /* pointer to next level of table */
|
|
} v;
|
|
};
|
|
|
|
int huft_build OF((unsigned *, unsigned, unsigned, ush *, ush *,
|
|
struct huft **, int *));
|
|
int huft_free OF((struct huft *));
|
|
int inflate_codes OF((struct huft *, struct huft *, int, int));
|
|
int inflate_stored OF((void));
|
|
int inflate_fixed OF((void));
|
|
int inflate_dynamic OF((void));
|
|
int inflate_block OF((int *));
|
|
int inflate OF((void));
|
|
int inflate_free OF((void));
|
|
|
|
|
|
/* The inflate algorithm uses a sliding 32K byte window on the uncompressed
|
|
stream to find repeated byte strings. This is implemented here as a
|
|
circular buffer. The index is updated simply by incrementing and then
|
|
and'ing with 0x7fff (32K-1). */
|
|
/* It is left to other modules to supply the 32K area. It is assumed
|
|
to be usable as if it were declared "uch slide[32768];" or as just
|
|
"uch *slide;" and then malloc'ed in the latter case. The definition
|
|
must be in unzip.h, included above. */
|
|
unsigned wp; /* current position in slide */
|
|
|
|
|
|
/* Tables for deflate from PKZIP's appnote.txt. */
|
|
static unsigned 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};
|
|
static ush 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};
|
|
/* note: see note #13 above about the 258 in this list. */
|
|
static ush 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, 99, 99}; /* 99==invalid */
|
|
static ush 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};
|
|
static ush 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};
|
|
|
|
/* And'ing with mask[n] masks the lower n bits */
|
|
ush mask[] = {
|
|
0x0000,
|
|
0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
|
|
0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
|
|
};
|
|
|
|
|
|
/* Macros for inflate() bit peeking and grabbing.
|
|
The usage is:
|
|
|
|
NEEDBITS(j)
|
|
x = b & mask[j];
|
|
DUMPBITS(j)
|
|
|
|
where NEEDBITS makes sure that b has at least j bits in it, and
|
|
DUMPBITS removes the bits from b. The macros use the variable k
|
|
for the number of bits in b. Normally, b and k are register
|
|
variables for speed, and are initialized at the begining of a
|
|
routine that uses these macros from a global bit buffer and count.
|
|
|
|
In order to not ask for more bits than there are in the compressed
|
|
stream, the Huffman tables are constructed to only ask for just
|
|
enough bits to make up the end-of-block code (value 256). Then no
|
|
bytes need to be "returned" to the buffer at the end of the last
|
|
block. See the huft_build() routine.
|
|
*/
|
|
|
|
ulg bb; /* bit buffer */
|
|
unsigned bk; /* bits in bit buffer */
|
|
|
|
#ifndef CHECK_EOF
|
|
# define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE)<<k;k+=8;}}
|
|
#else
|
|
# define NEEDBITS(n) {while(k<(n)){int c=NEXTBYTE;if(c==EOF)return 1;\
|
|
b|=((ulg)c)<<k;k+=8;}}
|
|
#endif /* Piet Plomp: change "return 1" to "break" */
|
|
|
|
#define DUMPBITS(n) {b>>=(n);k-=(n);}
|
|
|
|
|
|
/*
|
|
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.
|
|
*/
|
|
|
|
|
|
int lbits = 9; /* bits in base literal/length lookup table */
|
|
int dbits = 6; /* bits in base distance lookup table */
|
|
|
|
|
|
/* If BMAX needs to be larger than 16, then h and x[] should be ulg. */
|
|
#define BMAX 16 /* maximum bit length of any code (16 for explode) */
|
|
#define N_MAX 288 /* maximum number of codes in any set */
|
|
|
|
|
|
unsigned hufts; /* track memory usage */
|
|
|
|
void *malloc(n)
|
|
int n;
|
|
{
|
|
void *p;
|
|
p = alloc(n + sizeof(n));
|
|
if (!p)
|
|
return(NULL);
|
|
*((int *)p) = n;
|
|
p += sizeof(n);
|
|
return(p);
|
|
}
|
|
|
|
int huft_build(b, n, s, d, e, t, m)
|
|
unsigned *b; /* code lengths in bits (all assumed <= BMAX) */
|
|
unsigned n; /* number of codes (assumed <= N_MAX) */
|
|
unsigned s; /* number of simple-valued codes (0..s-1) */
|
|
ush *d; /* list of base values for non-simple codes */
|
|
ush *e; /* list of extra bits for non-simple codes */
|
|
struct huft **t; /* result: starting table */
|
|
int *m; /* maximum lookup bits, returns actual */
|
|
/* Given a list of code lengths and a maximum table size, make a set of
|
|
tables to decode that set of codes. Return zero on success, one if
|
|
the given code set is incomplete (the tables are still built in this
|
|
case), two if the input is invalid (all zero length codes or an
|
|
oversubscribed set of lengths), and three if not enough memory.
|
|
The code with value 256 is special, and the tables are constructed
|
|
so that no bits beyond that code are fetched when that code is
|
|
decoded. */
|
|
{
|
|
unsigned a; /* counter for codes of length k */
|
|
unsigned c[BMAX+1]; /* bit length count table */
|
|
unsigned el; /* length of EOB code (value 256) */
|
|
unsigned f; /* i repeats in table every f entries */
|
|
int g; /* maximum code length */
|
|
int h; /* table level */
|
|
register unsigned i; /* counter, current code */
|
|
register unsigned j; /* counter */
|
|
register int k; /* number of bits in current code */
|
|
int lx[BMAX+1]; /* memory for l[-1..BMAX-1] */
|
|
int *l = lx+1; /* stack of bits per table */
|
|
register unsigned *p; /* pointer into c[], b[], or v[] */
|
|
register struct huft *q; /* points to current table */
|
|
struct huft r; /* table entry for structure assignment */
|
|
struct huft *u[BMAX]; /* table stack */
|
|
static unsigned v[N_MAX]; /* values in order of bit length */
|
|
register int w; /* bits before this table == (l * h) */
|
|
unsigned x[BMAX+1]; /* bit offsets, then code stack */
|
|
unsigned *xp; /* pointer into x */
|
|
int y; /* number of dummy codes added */
|
|
unsigned z; /* number of entries in current table */
|
|
|
|
|
|
/* Generate counts for each bit length */
|
|
el = n > 256 ? b[256] : BMAX; /* set length of EOB code, if any */
|
|
memzero((char *)c, sizeof(c));
|
|
p = b; i = n;
|
|
do {
|
|
c[*p]++; p++; /* assume all entries <= BMAX */
|
|
} while (--i);
|
|
if (c[0] == n) /* null input--all zero length codes */
|
|
{
|
|
*t = (struct huft *)NULL;
|
|
*m = 0;
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* Find minimum and maximum length, bound *m by those */
|
|
for (j = 1; j <= BMAX; j++)
|
|
if (c[j])
|
|
break;
|
|
k = j; /* minimum code length */
|
|
if ((unsigned)*m < j)
|
|
*m = j;
|
|
for (i = BMAX; i; i--)
|
|
if (c[i])
|
|
break;
|
|
g = i; /* maximum code length */
|
|
if ((unsigned)*m > i)
|
|
*m = i;
|
|
|
|
|
|
/* 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 2; /* bad input: more codes than bits */
|
|
if ((y -= c[i]) < 0)
|
|
return 2;
|
|
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[-1] = 0; /* no bits decoded yet */
|
|
u[0] = (struct huft *)NULL; /* just to keep compilers happy */
|
|
q = (struct huft *)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[h++]; /* add bits already decoded */
|
|
|
|
/* compute minimum size table less than or equal to *m bits */
|
|
z = (z = g - w) > (unsigned)*m ? *m : z; /* 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;
|
|
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 */
|
|
}
|
|
}
|
|
if ((unsigned)w + j > el && (unsigned)w < el)
|
|
j = el - w; /* make EOB code end at table */
|
|
z = 1 << j; /* table entries for j-bit table */
|
|
l[h] = j; /* set table size in stack */
|
|
|
|
/* allocate and link in new table */
|
|
if ((q = (struct huft *)malloc((z + 1)*sizeof(struct huft))) ==
|
|
(struct huft *)NULL)
|
|
{
|
|
if (h)
|
|
huft_free(u[0]);
|
|
return 3; /* not enough memory */
|
|
}
|
|
hufts += z + 1; /* track memory usage */
|
|
*t = q + 1; /* link to list for huft_free() */
|
|
*(t = &(q->v.t)) = (struct huft *)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.b = (uch)l[h-1]; /* bits to dump before this table */
|
|
r.e = (uch)(16 + j); /* bits in this table */
|
|
r.v.t = q; /* pointer to this table */
|
|
j = (i & ((1 << w) - 1)) >> (w - l[h-1]);
|
|
u[h-1][j] = r; /* connect to last table */
|
|
}
|
|
}
|
|
|
|
/* set up table entry in r */
|
|
r.b = (uch)(k - w);
|
|
if (p >= v + n)
|
|
r.e = 99; /* out of values--invalid code */
|
|
else if (*p < s)
|
|
{
|
|
r.e = (uch)(*p < 256 ? 16 : 15); /* 256 is end-of-block code */
|
|
r.v.n = *p++; /* simple code is just the value */
|
|
}
|
|
else
|
|
{
|
|
r.e = (uch)e[*p - s]; /* non-simple--look up in lists */
|
|
r.v.n = 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])
|
|
w -= l[--h]; /* don't need to update q */
|
|
}
|
|
}
|
|
|
|
|
|
/* return actual size of base table */
|
|
*m = l[0];
|
|
|
|
|
|
/* Return true (1) if we were given an incomplete table */
|
|
return y != 0 && g != 1;
|
|
}
|
|
|
|
|
|
|
|
int huft_free(t)
|
|
struct huft *t; /* table to free */
|
|
/* 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 struct huft *p, *q;
|
|
|
|
|
|
/* Go through linked list, freeing from the malloced (t[-1]) address. */
|
|
p = t;
|
|
while (p != (struct huft *)NULL)
|
|
{
|
|
q = (--p)->v.t;
|
|
free(((void *)p) - sizeof(int), ((int *)p)[-1]);
|
|
p = q;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
#ifdef ASM_INFLATECODES
|
|
# define inflate_codes(tl,td,bl,bd) flate_codes(tl,td,bl,bd,(uch *)slide)
|
|
int flate_codes OF((struct huft *, struct huft *, int, int, uch *));
|
|
|
|
#else
|
|
|
|
int inflate_codes(tl, td, bl, bd)
|
|
struct huft *tl, *td; /* literal/length and distance decoder tables */
|
|
int bl, bd; /* number of bits decoded by tl[] and td[] */
|
|
/* inflate (decompress) the codes in a deflated (compressed) block.
|
|
Return an error code or zero if it all goes ok. */
|
|
{
|
|
register unsigned e; /* table entry flag/number of extra bits */
|
|
unsigned n, d; /* length and index for copy */
|
|
unsigned w; /* current window position */
|
|
struct huft *t; /* pointer to table entry */
|
|
unsigned ml, md; /* masks for bl and bd bits */
|
|
register ulg b; /* bit buffer */
|
|
register unsigned k; /* number of bits in bit buffer */
|
|
|
|
|
|
/* make local copies of globals */
|
|
b = bb; /* initialize bit buffer */
|
|
k = bk;
|
|
w = wp; /* initialize window position */
|
|
|
|
|
|
/* inflate the coded data */
|
|
ml = mask[bl]; /* precompute masks for speed */
|
|
md = mask[bd];
|
|
while (1) /* do until end of block */
|
|
{
|
|
NEEDBITS((unsigned)bl)
|
|
if ((e = (t = tl + ((unsigned)b & ml))->e) > 16)
|
|
do {
|
|
if (e == 99)
|
|
return 1;
|
|
DUMPBITS(t->b)
|
|
e -= 16;
|
|
NEEDBITS(e)
|
|
} while ((e = (t = t->v.t + ((unsigned)b & mask[e]))->e) > 16);
|
|
DUMPBITS(t->b)
|
|
if (e == 16) /* then it's a literal */
|
|
{
|
|
slide[w++] = (uch)t->v.n;
|
|
if (w == WSIZE)
|
|
{
|
|
FLUSH(w);
|
|
w = 0;
|
|
}
|
|
}
|
|
else /* it's an EOB or a length */
|
|
{
|
|
/* exit if end of block */
|
|
if (e == 15)
|
|
break;
|
|
|
|
/* get length of block to copy */
|
|
NEEDBITS(e)
|
|
n = t->v.n + ((unsigned)b & mask[e]);
|
|
DUMPBITS(e);
|
|
|
|
/* decode distance of block to copy */
|
|
NEEDBITS((unsigned)bd)
|
|
if ((e = (t = td + ((unsigned)b & md))->e) > 16)
|
|
do {
|
|
if (e == 99)
|
|
return 1;
|
|
DUMPBITS(t->b)
|
|
e -= 16;
|
|
NEEDBITS(e)
|
|
} while ((e = (t = t->v.t + ((unsigned)b & mask[e]))->e) > 16);
|
|
DUMPBITS(t->b)
|
|
NEEDBITS(e)
|
|
d = w - t->v.n - ((unsigned)b & mask[e]);
|
|
DUMPBITS(e)
|
|
|
|
/* do the copy */
|
|
do {
|
|
n -= (e = (e = WSIZE - ((d &= WSIZE-1) > w ? d : w)) > n ? n : e);
|
|
#ifndef NOMEMCPY
|
|
if (w - d >= e) /* (this test assumes unsigned comparison) */
|
|
{
|
|
memcpy(slide + w, slide + d, e);
|
|
w += e;
|
|
d += e;
|
|
}
|
|
else /* do it slow to avoid memcpy() overlap */
|
|
#endif /* !NOMEMCPY */
|
|
do {
|
|
slide[w++] = slide[d++];
|
|
} while (--e);
|
|
if (w == WSIZE)
|
|
{
|
|
FLUSH(w);
|
|
w = 0;
|
|
}
|
|
} while (n);
|
|
}
|
|
}
|
|
|
|
|
|
/* restore the globals from the locals */
|
|
wp = w; /* restore global window pointer */
|
|
bb = b; /* restore global bit buffer */
|
|
bk = k;
|
|
|
|
|
|
/* done */
|
|
return 0;
|
|
}
|
|
|
|
#endif /* ASM_INFLATECODES */
|
|
|
|
|
|
|
|
int inflate_stored()
|
|
/* "decompress" an inflated type 0 (stored) block. */
|
|
{
|
|
unsigned n; /* number of bytes in block */
|
|
unsigned w; /* current window position */
|
|
register ulg b; /* bit buffer */
|
|
register unsigned k; /* number of bits in bit buffer */
|
|
|
|
|
|
/* make local copies of globals */
|
|
b = bb; /* initialize bit buffer */
|
|
k = bk;
|
|
w = wp; /* initialize window position */
|
|
|
|
|
|
/* go to byte boundary */
|
|
n = k & 7;
|
|
DUMPBITS(n);
|
|
|
|
|
|
/* get the length and its complement */
|
|
NEEDBITS(16)
|
|
n = ((unsigned)b & 0xffff);
|
|
DUMPBITS(16)
|
|
NEEDBITS(16)
|
|
if (n != (unsigned)((~b) & 0xffff))
|
|
return 1; /* error in compressed data */
|
|
DUMPBITS(16)
|
|
|
|
|
|
/* read and output the compressed data */
|
|
while (n--)
|
|
{
|
|
NEEDBITS(8)
|
|
slide[w++] = (uch)b;
|
|
if (w == WSIZE)
|
|
{
|
|
FLUSH(w);
|
|
w = 0;
|
|
}
|
|
DUMPBITS(8)
|
|
}
|
|
|
|
|
|
/* restore the globals from the locals */
|
|
wp = w; /* restore global window pointer */
|
|
bb = b; /* restore global bit buffer */
|
|
bk = k;
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* Globals for literal tables (built once) */
|
|
struct huft *fixed_tl = (struct huft *)NULL;
|
|
struct huft *fixed_td;
|
|
int fixed_bl, fixed_bd;
|
|
|
|
int inflate_fixed()
|
|
/* decompress an inflated type 1 (fixed Huffman codes) block. We should
|
|
either replace this with a custom decoder, or at least precompute the
|
|
Huffman tables. */
|
|
{
|
|
/* if first time, set up tables for fixed blocks */
|
|
if (fixed_tl == (struct huft *)NULL)
|
|
{
|
|
int i; /* temporary variable */
|
|
static unsigned l[288]; /* length list for huft_build */
|
|
|
|
/* literal table */
|
|
for (i = 0; i < 144; i++)
|
|
l[i] = 8;
|
|
for (; i < 256; i++)
|
|
l[i] = 9;
|
|
for (; i < 280; i++)
|
|
l[i] = 7;
|
|
for (; i < 288; i++) /* make a complete, but wrong code set */
|
|
l[i] = 8;
|
|
fixed_bl = 7;
|
|
if ((i = huft_build(l, 288, 257, cplens, cplext,
|
|
&fixed_tl, &fixed_bl)) != 0)
|
|
{
|
|
fixed_tl = (struct huft *)NULL;
|
|
return i;
|
|
}
|
|
|
|
/* distance table */
|
|
for (i = 0; i < 30; i++) /* make an incomplete code set */
|
|
l[i] = 5;
|
|
fixed_bd = 5;
|
|
if ((i = huft_build(l, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd)) > 1)
|
|
{
|
|
huft_free(fixed_tl);
|
|
fixed_tl = (struct huft *)NULL;
|
|
return i;
|
|
}
|
|
}
|
|
|
|
|
|
/* decompress until an end-of-block code */
|
|
return inflate_codes(fixed_tl, fixed_td, fixed_bl, fixed_bd) != 0;
|
|
}
|
|
|
|
|
|
|
|
int inflate_dynamic()
|
|
/* decompress an inflated type 2 (dynamic Huffman codes) block. */
|
|
{
|
|
int i; /* temporary variables */
|
|
unsigned j;
|
|
unsigned l; /* last length */
|
|
unsigned m; /* mask for bit lengths table */
|
|
unsigned n; /* number of lengths to get */
|
|
struct huft *tl; /* literal/length code table */
|
|
struct huft *td; /* distance code table */
|
|
int bl; /* lookup bits for tl */
|
|
int bd; /* lookup bits for td */
|
|
unsigned nb; /* number of bit length codes */
|
|
unsigned nl; /* number of literal/length codes */
|
|
unsigned nd; /* number of distance codes */
|
|
#ifdef PKZIP_BUG_WORKAROUND
|
|
static unsigned ll[288+32]; /* literal/length and distance code lengths */
|
|
#else
|
|
static unsigned ll[286+30]; /* literal/length and distance code lengths */
|
|
#endif
|
|
register ulg b; /* bit buffer */
|
|
register unsigned k; /* number of bits in bit buffer */
|
|
|
|
|
|
/* make local bit buffer */
|
|
b = bb;
|
|
k = bk;
|
|
|
|
|
|
/* read in table lengths */
|
|
NEEDBITS(5)
|
|
nl = 257 + ((unsigned)b & 0x1f); /* number of literal/length codes */
|
|
DUMPBITS(5)
|
|
NEEDBITS(5)
|
|
nd = 1 + ((unsigned)b & 0x1f); /* number of distance codes */
|
|
DUMPBITS(5)
|
|
NEEDBITS(4)
|
|
nb = 4 + ((unsigned)b & 0xf); /* number of bit length codes */
|
|
DUMPBITS(4)
|
|
#ifdef PKZIP_BUG_WORKAROUND
|
|
if (nl > 288 || nd > 32)
|
|
#else
|
|
if (nl > 286 || nd > 30)
|
|
#endif
|
|
return 1; /* bad lengths */
|
|
|
|
|
|
/* read in bit-length-code lengths */
|
|
for (j = 0; j < nb; j++)
|
|
{
|
|
NEEDBITS(3)
|
|
ll[border[j]] = (unsigned)b & 7;
|
|
DUMPBITS(3)
|
|
}
|
|
for (; j < 19; j++)
|
|
ll[border[j]] = 0;
|
|
|
|
|
|
/* build decoding table for trees--single level, 7 bit lookup */
|
|
bl = 7;
|
|
if ((i = huft_build(ll, 19, 19, NULL, NULL, &tl, &bl)) != 0)
|
|
{
|
|
if (i == 1)
|
|
huft_free(tl);
|
|
return i; /* incomplete code set */
|
|
}
|
|
|
|
|
|
/* read in literal and distance code lengths */
|
|
n = nl + nd;
|
|
m = mask[bl];
|
|
i = l = 0;
|
|
while ((unsigned)i < n)
|
|
{
|
|
NEEDBITS((unsigned)bl)
|
|
j = (td = tl + ((unsigned)b & m))->b;
|
|
DUMPBITS(j)
|
|
j = td->v.n;
|
|
if (j < 16) /* length of code in bits (0..15) */
|
|
ll[i++] = l = j; /* save last length in l */
|
|
else if (j == 16) /* repeat last length 3 to 6 times */
|
|
{
|
|
NEEDBITS(2)
|
|
j = 3 + ((unsigned)b & 3);
|
|
DUMPBITS(2)
|
|
if ((unsigned)i + j > n)
|
|
return 1;
|
|
while (j--)
|
|
ll[i++] = l;
|
|
}
|
|
else if (j == 17) /* 3 to 10 zero length codes */
|
|
{
|
|
NEEDBITS(3)
|
|
j = 3 + ((unsigned)b & 7);
|
|
DUMPBITS(3)
|
|
if ((unsigned)i + j > n)
|
|
return 1;
|
|
while (j--)
|
|
ll[i++] = 0;
|
|
l = 0;
|
|
}
|
|
else /* j == 18: 11 to 138 zero length codes */
|
|
{
|
|
NEEDBITS(7)
|
|
j = 11 + ((unsigned)b & 0x7f);
|
|
DUMPBITS(7)
|
|
if ((unsigned)i + j > n)
|
|
return 1;
|
|
while (j--)
|
|
ll[i++] = 0;
|
|
l = 0;
|
|
}
|
|
}
|
|
|
|
|
|
/* free decoding table for trees */
|
|
huft_free(tl);
|
|
|
|
|
|
/* restore the global bit buffer */
|
|
bb = b;
|
|
bk = k;
|
|
|
|
|
|
/* build the decoding tables for literal/length and distance codes */
|
|
bl = lbits;
|
|
if ((i = huft_build(ll, nl, 257, cplens, cplext, &tl, &bl)) != 0)
|
|
{
|
|
return i; /* incomplete code set */
|
|
}
|
|
bd = dbits;
|
|
if ((i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0)
|
|
{
|
|
if (i == 1 && !qflag) {
|
|
#ifdef PKZIP_BUG_WORKAROUND
|
|
i = 0;
|
|
}
|
|
#else
|
|
huft_free(td);
|
|
}
|
|
huft_free(tl);
|
|
return i; /* incomplete code set */
|
|
#endif
|
|
}
|
|
|
|
|
|
/* decompress until an end-of-block code */
|
|
if (inflate_codes(tl, td, bl, bd))
|
|
return 1;
|
|
|
|
|
|
/* free the decoding tables, return */
|
|
huft_free(tl);
|
|
huft_free(td);
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
int inflate_block(e)
|
|
int *e; /* last block flag */
|
|
/* decompress an inflated block */
|
|
{
|
|
unsigned t; /* block type */
|
|
register ulg b; /* bit buffer */
|
|
register unsigned k; /* number of bits in bit buffer */
|
|
|
|
|
|
/* make local bit buffer */
|
|
b = bb;
|
|
k = bk;
|
|
|
|
|
|
/* read in last block bit */
|
|
NEEDBITS(1)
|
|
*e = (int)b & 1;
|
|
DUMPBITS(1)
|
|
|
|
|
|
/* read in block type */
|
|
NEEDBITS(2)
|
|
t = (unsigned)b & 3;
|
|
DUMPBITS(2)
|
|
|
|
|
|
/* restore the global bit buffer */
|
|
bb = b;
|
|
bk = k;
|
|
|
|
|
|
/* inflate that block type */
|
|
if (t == 2)
|
|
return inflate_dynamic();
|
|
if (t == 0)
|
|
return inflate_stored();
|
|
if (t == 1)
|
|
return inflate_fixed();
|
|
|
|
|
|
/* bad block type */
|
|
return 2;
|
|
}
|
|
|
|
|
|
|
|
int inflate()
|
|
/* decompress an inflated entry */
|
|
{
|
|
int e; /* last block flag */
|
|
int r; /* result code */
|
|
unsigned h; /* maximum struct huft's malloc'ed */
|
|
|
|
|
|
/* initialize window, bit buffer */
|
|
wp = 0;
|
|
bk = 0;
|
|
bb = 0;
|
|
|
|
|
|
/* decompress until the last block */
|
|
h = 0;
|
|
do {
|
|
hufts = 0;
|
|
if ((r = inflate_block(&e)) != 0)
|
|
return r;
|
|
if (hufts > h)
|
|
h = hufts;
|
|
} while (!e);
|
|
|
|
|
|
/* flush out slide */
|
|
FLUSH(wp);
|
|
|
|
|
|
/* return success */
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
int inflate_free()
|
|
{
|
|
if (fixed_tl != (struct huft *)NULL)
|
|
{
|
|
huft_free(fixed_td);
|
|
huft_free(fixed_tl);
|
|
fixed_td = fixed_tl = (struct huft *)NULL;
|
|
}
|
|
return 0;
|
|
}
|