sandy@conexch.UUCP (Sandford Zelkovitz) (04/08/89)
The following code is the fixed version of unzip, written by S.H. Smith. It
now compiles problem under Xenix386 and also fixes the bug in subroutine
get_string. I hope the author does not mind that I have reposted his
program. ............ Sandy
---------------cut/ax/hack/snip/chop/whatever here -----------------------
#!/bin/sh
# shar: Shell Archiver (v1.22)
#
# Run the following text with /bin/sh to create:
# Makefile
# addbfcrc.c
# unzipbsd.c
#
sed 's/^X//' << 'SHAR_EOF' > Makefile &&
X# Makefile for unzipbsd
X
X
X# "make unzip" -- makes unzip in current directory
X# "make install" -- makes unzip, then moves it into DESTDIR defined below
X# "make clean" -- deletes object files and executable unzip from current dir
X# "make shar" -- make a SHell ARchive
X
X# Directory where we want to move executable unzip on "make install"
XDESTDIR=/usr/public
X
X# CFLAGS are flags for the C compiler. LDFLAGS are flags for the loader.
XCFLAGS= -O
XLDFLAGS= -s
X
XCC=cc
X
X.c.o :
X $(CC) -c $(CFLAGS) $*.c
X
XOBJS = unzipbsd.o addbfcrc.o
X
Xunzip: $(OBJS)
X cc $(LDFLAGS) -o unzip $(OBJS)
X
Xunzip.o: unzip.c
X
Xaddbfcrc.o: addbfcrc.c
X
Xinstall: unzip
X mv unzip $(DESTDIR)/unzip
X
Xclean:
X /bin/rm -f $(OBJS) core unzip
X
Xshar:
X @shar -a Makefile unzipbsd.c addbfcrc.c > unzipbsd.shar
SHAR_EOF
chmod 0644 Makefile || echo "restore of Makefile fails"
sed 's/^X//' << 'SHAR_EOF' > addbfcrc.c &&
X/* @(#) addbfcrc.c 1.5 89/03/08 14:58:35 */
X/* Most of following CRC-32 stuff is from zmodem source code */
X
X#ifndef LINT
Xstatic char sccsid[]="::[[ @(#) addbfcrc.c 1.6 89/03/10 19:08:47 ]]::";
X#endif
X
X/* I claim no copyright over the contents of this file. -- Rahul Dhesi */
X
X/*
XChecksum: 951252172 (check or update this with "brik")
X*/
X
X
Xlong crccode;
X
X/*
X * Copyright (C) 1986 Gary S. Brown. You may use this program, or
X * code or tables extracted from it, as desired without restriction.
X */
X
X/* First, the polynomial itself and its table of feedback terms. The */
X/* polynomial is */
X/* X^32+X^26+X^23+X^22+X^16+X^12+X^11+X^10+X^8+X^7+X^5+X^4+X^2+X^1+X^0 */
X/* Note that we take it "backwards" and put the highest-order term in */
X/* the lowest-order bit. The X^32 term is "implied"; the LSB is the */
X/* X^31 term, etc. The X^0 term (usually shown as "+1") results in */
X/* the MSB being 1. */
X
X/* Note that the usual hardware shift register implementation, which */
X/* is what we're using (we're merely optimizing it by doing eight-bit */
X/* chunks at a time) shifts bits into the lowest-order term. In our */
X/* implementation, that means shifting towards the right. Why do we */
X/* do it this way? Because the calculated CRC must be transmitted in */
X/* order from highest-order term to lowest-order term. UARTs transmit */
X/* characters in order from LSB to MSB. By storing the CRC this way, */
X/* we hand it to the UART in the order low-byte to high-byte; the UART */
X/* sends each low-bit to hight-bit; and the result is transmission bit */
X/* by bit from highest- to lowest-order term without requiring any bit */
X/* shuffling on our part. Reception works similarly. */
X
X/* The feedback terms table consists of 256, 32-bit entries. Notes: */
X/* */
X/* The table can be generated at runtime if desired; code to do so */
X/* is shown later. It might not be obvious, but the feedback */
X/* terms simply represent the results of eight shift/xor opera- */
X/* tions for all combinations of data and CRC register values. */
X/* */
X/* The values must be right-shifted by eight bits by the "updcrc" */
X/* logic; the shift must be unsigned (bring in zeroes). On some */
X/* hardware you could probably optimize the shift in assembler by */
X/* using byte-swap instructions. */
X
Xlong crc_32_tab[] = { /* CRC polynomial 0xedb88320 */
X 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
X 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
X 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
X 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
X 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
X 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
X 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,
X 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
X 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
X 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
X 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,
X 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
X 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,
X 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
X 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
X 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
X 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,
X 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
X 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,
X 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
X 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
X 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
X 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,
X 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
X 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
X 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
X 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
X 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
X 0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,
X 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
X 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,
X 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
X 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
X 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
X 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
X 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
X 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,
X 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
X 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
X 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
X 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,
X 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
X 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,
X 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
X 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
X 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
X 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,
X 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
X 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,
X 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
X 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
X 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
X 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,
X 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
X 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
X 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
X 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
X 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
X 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,
X 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
X 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,
X 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
X 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
X 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
X};
X
Xaddbfcrc (buf, size)
Xregister char *buf;
Xregister int size;
X{
X int i;
X for (i = 0; i < size; i ++) {
X crccode = crc_32_tab[(int) ((crccode) ^ (buf[i])) & 0xff] ^
X (((crccode) >> 8) & 0x00FFFFFFL);
X }
X}
SHAR_EOF
chmod 0644 addbfcrc.c || echo "restore of addbfcrc.c fails"
sed 's/^X//' << 'SHAR_EOF' > unzipbsd.c &&
X/*
X * Quick hack to use on BSD, on a DEC VAX
X * By Michael Enkelis @ tektronix 04/03/89
X *
X */
X
X/*
X * Copyright 1987, 1989 Samuel H. Smith; All rights reserved
X *
X * This is a component of the ProDoor System.
X * Do not distribute modified versions without my permission.
X * Do not remove or alter this notice or any other copyright notice.
X * If you use this in your own program you must distribute source code.
X * Do not use any of this in a commercial product.
X *
X */
X
X/*
X * UnZip - A simple zipfile extract utility
X *
X */
X
X#define version "UnZip: Zipfile Extract v1.1b of 04-03-89; (C) 1989 S.H.Smith"
X
Xtypedef unsigned char byte;
Xtypedef unsigned int word;
Xtypedef unsigned long longint;
Xtypedef unsigned char boolean;
X#define STRSIZ 256
X
X#include <stdio.h>
X#include <sys/types.h>
X#include <sys/file.h>
X#include <sys/stat.h>
X#include <fcntl.h>
X
X
Xint errcount = 0; /* count of errors */
Xint debugging = 0; /* debug enable flag */
Xint verbose = 0; /* be verbose */
Xint test_zip = 0; /* test CRC's only */
X
X#ifdef M_XENIX
Xint L_SET = 1;
X#endif
X
X/*
XInitializing the CRC to all one bits avoids failure of detection
Xshould entire data stream get cyclically bit-shifted by one position.
XThe calculation of the probability of this happening is left as
Xan exercise for the reader.
X*/
X#define INITCRC 0xFFFFFFFFL;
Xextern long crccode;
X
X/* ----------------------------------------------------------- */
X/*
X * Zipfile layout declarations
X *
X */
X
Xtypedef longint signature_type;
X
X
X#define local_file_header_signature 0x04034b50L
X
Xchar *strchr();
X
Xtypedef struct local_file_header {
X word version_needed_to_extract;
X word general_purpose_bit_flag;
X word compression_method;
X word last_mod_file_time;
X word last_mod_file_date;
X longint crc32;
X longint compressed_size;
X longint uncompressed_size;
X word filename_length;
X word extra_field_length;
X } local_file_header;
X
X#define central_file_header_signature 0x02014b50L
X
Xtypedef struct central_directory_file_header {
X word version_made_by;
X word version_needed_to_extract;
X word general_purpose_bit_flag;
X word compression_method;
X word last_mod_file_time;
X word last_mod_file_date;
X longint crc32;
X longint compressed_size;
X longint uncompressed_size;
X word filename_length;
X word extra_field_length;
X word file_comment_length;
X word disk_number_start;
X word internal_file_attributes;
X longint external_file_attributes;
X longint relative_offset_local_header;
X } central_directory_file_header;
X
X#define end_central_dir_signature 0x06054b50L
X
Xtypedef struct end_central_dir_record {
X word number_this_disk;
X word number_disk_with_start_central_directory;
X word total_entries_central_dir_on_this_disk;
X word total_entries_central_dir;
X longint size_central_directory;
X longint offset_start_central_directory;
X word zipfile_comment_length;
X } end_central_dir_record;
X
X
X/* ----------------------------------------------------------- */
X/*
X * input file variables
X *
X */
X
X
X#define uinbufsize 512L /* input buffer size */
X byte inbuf[uinbufsize];
X
X boolean zipeof;
X longint csize;
X longint cusize;
X int cmethod;
X int inpos;
X int incnt;
X int pc;
X int pcbits;
X int pcbitv;
X
X int zipfd;
X char zipfn[STRSIZ];
X local_file_header lrec;
X
X
X
X
X/* ----------------------------------------------------------- */
X/*
X * output stream variables
X *
X */
X
X
X byte outbuf[4096]; /* for rle look-back */
X longint outpos; /* absolute position in outfile */
X int outcnt;
X
X int outfd;
X char filename[STRSIZ];
X char extra[STRSIZ];
X
X
X
X/* ----------------------------------------------------------- */
X/*
X * shrink/reduce working storage
X *
X */
X
X
X int factor;
X byte followers[256][64];
X byte Slen[256];
X int ExState;
X int C;
X int V;
X int Len;
X
X#define max_bits 13
X#define init_bits 9
X#define hsize 8192
X#define first_ent 257
X#define clear 256
X
X typedef int hsize_array_integer[hsize+1];
X typedef byte hsize_array_byte[hsize+1];
X
X hsize_array_integer prefix_of;
X hsize_array_byte suffix_of;
X hsize_array_byte stack;
X
X int cbits;
X int maxcode;
X int free_ent;
X int maxcodemax;
X int offset;
X int sizex;
X
X
X/* ------------------------------------------------------------- */
X
Xskip_csize()
X{
X lseek(zipfd,csize,L_SET);
X zipeof = 1;
X csize = 0L;
X incnt = 0;
X}
X
X
X/* ------------------------------------------------------------- */
X
XReadByte(x)
Xint *x;
X{
X if (incnt == 0)
X {
X if (csize == 0L)
X {
X zipeof = 1;
X return;
X }
X
X inpos = sizeof(inbuf);
X if (inpos > csize)
X inpos = (int)csize;
X incnt = read(zipfd,inbuf,inpos);
X
X inpos = 1;
X csize -= incnt;
X }
X
X *x = inbuf[inpos-1];
X inpos++;
X incnt--;
X}
X
X
X/* ------------------------------------------------------------- */
X
XReadBits(bits,x)
Xint bits,*x;
X /* read the specified number of bits */
X{
X int bit;
X int bitv;
X
X *x = 0;
X bitv = 1;
X
X for (bit = 0; bit <= bits-1; bit++)
X {
X
X if (pcbits > 0)
X {
X pcbits--;
X pcbitv = pcbitv << 1;
X }
X else
X
X {
X ReadByte(&pc);
X pcbits = 7;
X pcbitv = 1;
X }
X
X if ((pc & pcbitv) != 0)
X *x = *x | bitv;
X
X bitv = (int) (bitv << 1);
X }
X
X}
X
X
X/* ---------------------------------------------------------- */
X
Xget_string(len, s)
Xint len;
Xchar *s;
X{
X read(zipfd,s,len);
X s[len] = 0;
X}
X
X
X/* ------------------------------------------------------------- */
X
XOutByte(c)
Xint c;
X /* output each character from archive to screen */
X{
X outbuf[outcnt /* outpos % sizeof(outbuf) */] = c;
X outpos++;
X outcnt++;
X
X if (outcnt == sizeof(outbuf))
X {
X if (test_zip == 0)
X write(outfd,outbuf,outcnt);
X addbfcrc (outbuf, outcnt);
X outcnt = 0;
X printf(".");
X }
X}
X
X
X/* ----------------------------------------------------------- */
X
Xreduce_L(x)
Xint x;
X {
X switch (factor) {
X case 1: return x & 0x7f;
X case 2: return x & 0x3f;
X case 3: return x & 0x1f;
X case 4: return x & 0x0f;
X }
X return 0; /* error */
X }
X
X
Xreduce_F(x)
Xint x;
X {
X switch (factor) {
X case 1: if (x == 127) return 2; else return 3;
X case 2: if (x == 63) return 2; else return 3;
X case 3: if (x == 31) return 2; else return 3;
X case 4: if (x == 15) return 2; else return 3;
X }
X return 0; /* error */
X }
X
X
Xreduce_D(x,y)
Xint x,y;
X {
X switch (factor) {
X case 1: return ((x >> 7) & 0x01) * 256 + y + 1;
X case 2: return ((x >> 6) & 0x03) * 256 + y + 1;
X case 3: return ((x >> 5) & 0x07) * 256 + y + 1;
X case 4: return ((x >> 4) & 0x0f) * 256 + y + 1;
X }
X return 0; /* error */
X }
X
X
Xreduce_B(x)
Xint x;
X /* number of bits needed to encode the specified number */
X {
X switch (x - 1) {
X
X case 0:
X case 1: return 1;
X
X case 2:
X case 3: return 2;
X
X case 4:
X case 5:
X case 6:
X case 7: return 3;
X
X case 8:
X case 9:
X case 10:
X case 11:
X case 12:
X case 13:
X case 14:
X case 15: return 4;
X
X case 16:
X case 17:
X case 18:
X case 19:
X case 20:
X case 21:
X case 22:
X case 23:
X case 24:
X case 25:
X case 26:
X case 27:
X case 28:
X case 29:
X case 30:
X case 31: return 5;
X
X case 32:
X case 33:
X case 34:
X case 35:
X case 36:
X case 37:
X case 38:
X case 39:
X case 40:
X case 41:
X case 42:
X case 43:
X case 44:
X case 45:
X case 46:
X case 47:
X case 48:
X case 49:
X case 50:
X case 51:
X case 52:
X case 53:
X case 54:
X case 55:
X case 56:
X case 57:
X case 58:
X case 59:
X case 60:
X case 61:
X case 62:
X case 63: return 6;
X
X case 64:
X case 65:
X case 66:
X case 67:
X case 68:
X case 69:
X case 70:
X case 71:
X case 72:
X case 73:
X case 74:
X case 75:
X case 76:
X case 77:
X case 78:
X case 79:
X case 80:
X case 81:
X case 82:
X case 83:
X case 84:
X case 85:
X case 86:
X case 87:
X case 88:
X case 89:
X case 90:
X case 91:
X case 92:
X case 93:
X case 94:
X case 95:
X case 96:
X case 97:
X case 98:
X case 99:
X case 100:
X case 101:
X case 102:
X case 103:
X case 104:
X case 105:
X case 106:
X case 107:
X case 108:
X case 109:
X case 110:
X case 111:
X case 112:
X case 113:
X case 114:
X case 115:
X case 116:
X case 117:
X case 118:
X case 119:
X case 120:
X case 121:
X case 122:
X case 123:
X case 124:
X case 125:
X case 126:
X case 127: return 7;
X
X default: return 8;
X }
X }
X
X
X
X/* ----------------------------------------------------------- */
X
XExpand(c)
Xint c;
X {
X#define DLE 144
X
X switch (ExState) {
X
X case 0:
X if (c != DLE)
X OutByte(c);
X else
X ExState = 1;
X break;
X
X case 1:
X if (c != 0)
X {
X V = c;
X Len = reduce_L(V);
X ExState = reduce_F(Len);
X }
X else
X {
X OutByte(DLE);
X ExState = 0;
X }
X break;
X
X case 2: {
X Len = Len + c;
X ExState = 3;
X }
X break;
X
X case 3: {
X int i;
X longint offset = reduce_D(V,c);
X longint op = outpos - offset;
X
X for (i = 0; i <= Len + 2; i++)
X {
X if (op < 0L)
X OutByte(0);
X else
X OutByte(outbuf[(int)(op % sizeof(outbuf))]);
X op++;
X }
X
X ExState = 0;
X }
X break;
X }
X }
X
X
X/* ----------------------------------------------------------- */
X
XLoadFollowers()
X {
X int x;
X int i;
X int b;
X
X for (x = 255; x >= 0; x--)
X {
X ReadBits(6,&b);
X Slen[x] = b;
X
X for (i = 0; i < Slen[x]; i++)
X {
X ReadBits(8,&b);
X followers[x][i] = b;
X }
X }
X }
X
X
X
X/* ----------------------------------------------------------- */
X
X/*
X * The Reducing algorithm is actually a combination of two
X * distinct algorithms. The first algorithm compresses repeated
X * byte sequences, and the second algorithm takes the compressed
X * stream from the first algorithm and applies a probabilistic
X * compression method.
X *
X */
X
XunReduce()
X /* expand probablisticly reduced data */
X
X {
X
X int lchar;
X int lout;
X int I;
X
X factor = cmethod - 1;
X
X if ((factor < 1) || (factor > 4))
X {
X skip_csize();
X return;
X }
X
X ExState = 0;
X LoadFollowers();
X lchar = 0;
X
X while ((!zipeof) && (outpos < cusize))
X {
X
X if (Slen[lchar] == 0)
X ReadBits(8,&lout);
X else
X
X {
X ReadBits(1,&lout);
X if (lout != 0)
X ReadBits(8,&lout);
X else
X {
X ReadBits(reduce_B(Slen[lchar]),&I);
X lout = followers[lchar][I];
X }
X }
X
X Expand(lout);
X lchar = lout;
X }
X}
X
X
X/* ------------------------------------------------------------- */
X/*
X * Shrinking is a Dynamic Ziv-Lempel-Welch compression algorithm
X * with partial clearing.
X *
X */
X
Xpartial_clear()
X{
X int pr;
X int cd;
X
X
X /* mark all nodes as potentially unused */
X for (cd = first_ent; cd < free_ent; cd++)
X prefix_of[cd] |= 0x8000;
X
X
X /* unmark those that are used by other nodes */
X for (cd = first_ent; cd < free_ent; cd++)
X {
X pr = prefix_of[cd] & 0x7fff; /* reference to another node? */
X if (pr >= first_ent) /* flag node as referenced */
X prefix_of[pr] &= 0x7fff;
X }
X
X
X /* clear the ones that are still marked */
X for (cd = first_ent; cd < free_ent; cd++)
X if ((prefix_of[cd] & 0x8000) != 0)
X prefix_of[cd] = -1;
X
X
X /* find first cleared node as next free_ent */
X free_ent = first_ent;
X while ((free_ent < maxcodemax) && (prefix_of[free_ent] != -1))
X free_ent++;
X}
X
X
X/* ------------------------------------------------------------- */
X
XunShrink()
X
X{
X int stackp;
X int finchar;
X int code;
X int oldcode;
X int incode;
X
X
X /* decompress the file */
X maxcodemax = 1 << max_bits;
X cbits = init_bits;
X maxcode = (1 << cbits) - 1;
X free_ent = first_ent;
X offset = 0;
X sizex = 0;
X
X for (code = maxcodemax; code > 255; code--)
X prefix_of[code] = -1;
X
X for (code = 255; code >= 0; code--)
X {
X prefix_of[code] = 0;
X suffix_of[code] = code;
X }
X
X ReadBits(cbits,&oldcode);
X if (zipeof) return;
X finchar = oldcode;
X
X OutByte(finchar);
X
X stackp = 0;
X
X while ((!zipeof))
X {
X ReadBits(cbits,&code);
X if (zipeof) return;
X
X while (code == clear)
X {
X ReadBits(cbits,&code);
X
X switch (code) {
X
X case 1: {
X cbits++;
X if (cbits == max_bits)
X maxcode = maxcodemax;
X else
X maxcode = (1 << cbits) - 1;
X }
X break;
X
X case 2:
X partial_clear();
X break;
X }
X
X ReadBits(cbits,&code);
X if (zipeof) return;
X }
X
X
X /* special case for KwKwK string */
X incode = code;
X if (prefix_of[code] == -1)
X {
X stack[stackp] = finchar;
X stackp++;
X code = oldcode;
X }
X
X
X /* generate output characters in reverse order */
X while (code >= first_ent)
X {
X stack[stackp] = suffix_of[code];
X stackp++;
X code = prefix_of[code];
X }
X
X finchar = suffix_of[code];
X stack[stackp] = finchar;
X stackp++;
X
X
X /* and put them out in forward order */
X while (stackp > 0)
X {
X stackp--;
X OutByte(stack[stackp]);
X }
X
X
X /* generate new entry */
X code = free_ent;
X if (code < maxcodemax)
X {
X prefix_of[code] = oldcode;
X suffix_of[code] = finchar;
X while ((free_ent < maxcodemax) && (prefix_of[free_ent] != -1))
X free_ent++;
X }
X
X
X /* remember previous code */
X oldcode = incode;
X }
X
X}
X
X
X/* ---------------------------------------------------------- */
X
Xextract_member()
X{
X int b;
X
Xfor (b=0; b<sizeof(outbuf); b++) outbuf[b]=0;
X pcbits = 0;
X incnt = 0;
X outpos = 0L;
X outcnt = 0;
X zipeof = 0;
X
X
X if (test_zip == 0) {
X outfd = creat(filename,S_IWRITE|S_IREAD);
X if (outfd < 1)
X {
X printf("Can't create output: %s\n",filename);
X exit(1);
X }
X close(outfd);
X outfd = open(filename,O_RDWR);
X }
X
X if (test_zip)
X printf(" Testing: %s ...",filename);
X
X switch (cmethod) {
X
X case 0: /* stored */
X {
X if (test_zip == 0)
X printf(" Extract: %s ...",filename);
X while ((!zipeof))
X {
X ReadByte(&b);
X OutByte(b);
X }
X }
X break;
X
X case 1: {
X if (test_zip == 0)
X printf("UnShrink: %s ...",filename);
X unShrink();
X }
X break;
X
X case 2:
X case 3:
X case 4:
X case 5: {
X if (test_zip == 0)
X printf(" Expand: %s ...",filename);
X unReduce();
X }
X break;
X
X default: printf("Unknown compression method.");
X }
X
X if (outcnt > 0) {
X if (test_zip == 0)
X write(outfd,outbuf,outcnt);
X addbfcrc (outbuf, outcnt);
X }
X
X if (test_zip == 0)
X close(outfd);
X
X if ((crccode + lrec.crc32) == -1)
X printf(" Ok");
X else
X printf(" Bad");
X
X if (verbose)
X printf(" [%d]\n",crccode);
X else
X printf("\n");
X}
X
X
X/* ---------------------------------------------------------- */
X
X/* UNIX support routines: Michael Enkelis */
Xget_byte()
X{
X unsigned int nibble;
X read(zipfd,&nibble,1);
X return (nibble & 0xff);
X}
X
Xget_word()
X{
X unsigned int nibble[2];
X nibble[0] = get_byte();
X nibble[1] = get_byte();
X return (int) (nibble[0] | nibble[1] << 8);
X}
X
Xget_long()
X{
X unsigned int nibble[4];
X nibble[0] = get_byte();
X nibble[1] = get_byte();
X nibble[2] = get_byte();
X nibble[3] = get_byte();
X return (long) ((unsigned long) nibble[0] |
X ((unsigned long) nibble[1] << 8) |
X ((unsigned long) nibble[2] << 16) |
X ((unsigned long) nibble[3] << 24));
X}
X/** End of added support routines **/
X
Xprocess_local_file_header()
X{
X lrec.version_needed_to_extract = get_word();
X lrec.general_purpose_bit_flag = get_word();
X lrec.compression_method = get_word();
X lrec.last_mod_file_time = get_word();
X lrec.last_mod_file_date = get_word();
X lrec.crc32 = get_long();
X lrec.compressed_size = get_long();
X lrec.uncompressed_size = get_long();
X lrec.filename_length = get_word();
X lrec.extra_field_length = get_word();
X
X get_string(lrec.filename_length,filename);
X get_string(lrec.extra_field_length,extra);
X
X if (debugging) {
X printf("Version used : %d\n",lrec.version_needed_to_extract);
X printf("Bit flags : %d\n",lrec.general_purpose_bit_flag);
X printf("Compression : %d\n",lrec.compression_method);
X printf("Mod time : %d\n",lrec.last_mod_file_time);
X printf("Mod date : %d\n",lrec.last_mod_file_date);
X printf("Crc32 : %d\n",~lrec.crc32);
X printf("Compressed size : %d\n",lrec.compressed_size);
X printf("Normal file size: %d\n",lrec.uncompressed_size);
X printf("File name : %s.%s\n",filename,extra);
X }
X
X csize = lrec.compressed_size;
X cusize = lrec.uncompressed_size;
X cmethod = lrec.compression_method;
X
X crccode = INITCRC;
X extract_member();
X}
X
X
X/* ---------------------------------------------------------- */
X
Xprocess_central_file_header()
X{
X central_directory_file_header rec;
X char filename[STRSIZ];
X char extra[STRSIZ];
X char comment[STRSIZ];
X
X rec.version_made_by = get_word();
X rec.version_needed_to_extract = get_word();
X rec.general_purpose_bit_flag = get_word();
X rec.compression_method = get_word();
X rec.last_mod_file_time = get_word();
X rec.last_mod_file_date = get_word();
X rec.crc32 = get_long();
X rec.compressed_size = get_long();
X rec.uncompressed_size = get_long();
X rec.filename_length = get_word();
X rec.extra_field_length = get_word();
X rec.file_comment_length = get_word();
X rec.disk_number_start = get_word();
X rec.internal_file_attributes = get_word();
X rec.external_file_attributes = get_long();
X rec.relative_offset_local_header = get_long();
X
X get_string(rec.filename_length,filename);
X get_string(rec.extra_field_length,extra);
X get_string(rec.file_comment_length,comment);
X
X crccode = INITCRC;
X}
X
X
X/* ---------------------------------------------------------- */
X
Xprocess_end_central_dir()
X{
X end_central_dir_record rec;
X char comment[STRSIZ];
X
X rec.number_this_disk = get_word();
X rec.number_disk_with_start_central_directory = get_word();
X rec.total_entries_central_dir_on_this_disk = get_word();
X rec.total_entries_central_dir = get_word();
X rec.size_central_directory = get_long();
X rec.offset_start_central_directory = get_long();
X rec.zipfile_comment_length = get_word();
X
X get_string(rec.zipfile_comment_length,comment);
X}
X
X
X/* ---------------------------------------------------------- */
X
Xprocess_headers()
X{
X longint sig;
X
X while (1)
X {
X if (read(zipfd,&sig,sizeof(sig)) != sizeof(sig))
X return;
X else
X
X if (sig == local_file_header_signature)
X process_local_file_header();
X else
X
X if (sig == central_file_header_signature)
X process_central_file_header();
X else
X
X if (sig == end_central_dir_signature)
X {
X process_end_central_dir();
X return;
X }
X
X else
X {
X printf("Invalid Zipfile Header\n");
X return;
X }
X }
X
X}
X
X
X/* ---------------------------------------------------------- */
X
Xextract_zipfile()
X{
X zipfd = open(zipfn,O_RDONLY);
X if (zipfd < 1) {
X printf("Can't open input file: %s\n",zipfn);
X return;
X }
X
X process_headers();
X
X close(zipfd);
X}
X
X
X/* ---------------------------------------------------------- */
X/*
X * main program
X *
X */
X
Xmain(argc, argv)
Xint argc;
Xchar **argv;
X{
X int c; /* next option letter */
X int count = 0; /* count of required options seen */
X
X extern int optind; /* from getopt: next arg to process */
X extern int opterr; /* used by getopt */
X extern char *optarg;
X
X opterr = 0; /* so getopt won't print err msg */
X
X printf("\n");
X printf("%s\n",version);
X printf("Courtesy of: S.H.Smith and The Tool Shop BBS,(602) 279-2673.");
X printf("\nModified by Sanford <Sandy> Zelkovitz - XBBS - (714) 898-8634");
X printf("\n\n");
X
X while ((c = getopt (argc, argv, "dtv")) != EOF)
X {
X switch (c) {
X case 'd': debugging++; break;
X case 't': test_zip++; break;
X case 'v': verbose++; break;
X default: short_help();
X }
X }
X
X strcpy(zipfn,argv[optind]);
X if (strlen(zipfn) == 0)
X short_help();
X
X if (strchr(zipfn,'.') == NULL)
X strcat(zipfn,".zip");
X
X extract_zipfile();
X
X exit(0);
X}
X
Xshort_help()
X{
X printf("Usage: UnZip -tv file[.zip]\n");
X exit(1);
X}
SHAR_EOF
chmod 0644 unzipbsd.c || echo "restore of unzipbsd.c fails"
exit 0bturner@hpcvlx.HP.COM (Bill Turner) (04/12/89)
The only problem with both the original Unzip posting and this was that they were written for byte-swapping architectures. If you want to have it work on non-byte-swapping systems, apply the following changes: 1) All of the signature values need to be byte-swapped. I.e., local_file_header_signature is 0x504b0304L central_file_header_signature is 0x504b0102L end_central_dir_signature is 0x504b0506L 2) In the routine get_byte, declare nibble as unsigned char rather than unsigned int. ----Bill Turner HP Corvallis Workstation Operation
swh@hpsmtc1.HP.COM (Steve Harrold) (04/13/89)
Re: The UNZIP program Thank you for the "byte-swapped" and "nibble" corrections. An additional correction is that the declaration for the "get_long()" function should be "longint" rather than the default "int". Failure to do this ensures that the code calculates bad CRC32 checks on a machine that has 16-bit ints. The zip file is successfully extracted, but you get a series of unsettling "bad" messages. Furthermore, the "open()" functions have to set the file mode to include the "O_BINARY" attribute for those environments that distinguish "text" files from "binary" files (e.g. MSDOS). An additional question is the use of the symbol "L_SET" in the original posting. This has a value of 0 (from file "file.h") but I think the symbol L_INCR (value = 1) should be used. The XENIX adaptation sets L_SET = 1 to achieve this purpose. Can the original author comment on these fixes?