rmtodd@uokmax.UUCP (Richard Michael Todd) (12/10/87)
OK, here's compress for MINIX. I've put in a rather messy maze of #ifdefs
in there so that if you've got Aztec C, you can use the same source file
to compile a version for MS-DOS as well. To compile a MSDOS version with
Aztec C:
cc -DAZTEC86 compress.c
ln -o compress.exe compress.o -lc
To compile a MINIX version with Aztec C:
cc -DAZTEC86 -DMINIX compress.c
(then follow up with the usual junk to link with the MINIX library, use
dos2out, etc.)
To compile under MINIX:
cc -i -T. -DAZTEC86 -DMINIX compress.c
Note that compress won't work if it isn't compiled split I&D. Note also that
the MINIX cc-compiled version is about 40% slower than the Aztec-compiled
one.
Once you've got a MINIX version created, with whatever compiler you
used, move it to /usr/bin/compress and make links to it named /usr/bin/zcat
and /usr/bin/uncompress. This allows you to invoke compress under the
other two names and have it perform the appropriate functions. (Alas, you
can't make links under MS-DOS. Sigh.)
------------------------- cut here ----------------------------------
#!/bin/sh
# Shell archive created with Richard Todd's makeshar on Wed Dec 9 12:55:38 1987
echo x - compress.c
sed 's/^X//' >compress.c << 'EOF'
X/* Here is source that will compile with AZTEC C86. Define AZTEC86 and compile it.
X** it is completely self-contained - no makefile. Just "cc -dAZTEC86 compress ;
X**ln compress.o -lc".
X** for some debug output add -DDEBUG
X** for more add -DDEBUG -DDEBUG2 -DAZTECBITS=12 (won't work w 13 bits)
X**
X** It also has defines for the Metaware compiler, but since that is not yet very
X** popular, I won't include the functions that Metaware lacks (stat and utime).
X** Altered by Richard Todd to allow compilation for MINIX with Aztec cc and
X** the appropriate library:
X** cc -DMINIX -DAZTEC86 compress.c
X** ln -o compress.exe -S 1 crtso.o compress.o -lminix
X** dos2out -d compress.exe
X** If MINIX isn't defined and AZTEC86 is, PCDOS will be automatically defined.
X*/
X#ifdef _lint
X/* flags for gimpel's pc-lint */
X#define AZTEC86
X/*lint -e701 -e702 signed integers are shifted with reckless abandon */
X#endif
X/*
X * Compress - data compression program
X */
X#define min(a,b) ((a>b) ? b : a)
X
X/*
X * machine variants which require cc -Dmachine: pdp11, z8000
X * compiler variants for PC-DOS which require -Dcompiler: AZTEC86
X */
X
X/*******************************************************************
X*
X* IMPORTANT MODEL 16 NOTE
X*
X* cc -DM_XENIX -DUSERMEM=128000 compress.c -o compress
X*
X*******************************************************************/
X
X
X/*
X * Set USERMEM to the maximum amount of physical user memory available
X * in bytes. USERMEM is used to determine the maximum BITS that can be used
X * for compression.
X *
X * SACREDMEM is the amount of physical memory saved for others; compress
X * will hog the rest.
X */
X#ifndef SACREDMEM
X#define SACREDMEM 0
X#endif
X
X#ifndef USERMEM
X# define USERMEM 450000 /* default user memory */
X#endif
X
X#ifdef interdata /* (Perkin-Elmer) */
X#define SIGNED_COMPARE_SLOW /* signed compare is slower than unsigned */
X#endif
X
X#ifdef pdp11
X# define BITS 12 /* max bits/code for 16-bit machine */
X# define NO_UCHAR /* also if "unsigned char" functions as signed char */
X# undef USERMEM
X#endif /* pdp11 */ /* don't forget to compile with -i */
X
X#ifdef z8000
X# define BITS 12
X# undef vax /* weird preprocessor */
X# undef USERMEM
X#endif /* z8000 */
X
X#ifdef METAWARE
X#define REGISTER
X#define AZTEC86
X#include <stdlib.h>
X#include <string.h>
X#include <system.cf>
X#include <ufile.h>
X#else
X#define REGISTER register
X#endif /* METAWARE */
X
X#ifdef AZTEC86
Xvoid prratio(),cl_block(),cl_hash(),output(),decompress(),
Xcopystat(),writeerr(),compress(),Usage(),version();
X#ifdef AZTECBITS
X# define BITS AZTECBITS
X#else
X# define BITS 13
X#endif
X# undef USERMEM
X#endif /* AZTEC86 */
X
X#ifdef USERMEM
X# if USERMEM >= (433484+SACREDMEM)
X# define PBITS 16
X# else
X# if USERMEM >= (229600+SACREDMEM)
X# define PBITS 15
X# else
X# if USERMEM >= (127536+SACREDMEM)
X# define PBITS 14
X# else
X# if USERMEM >= (73464+SACREDMEM)
X# define PBITS 13
X# else
X# define PBITS 12
X# endif
X# endif
X# endif
X# endif
X# undef USERMEM
X#endif /* USERMEM */
X
X#ifdef PBITS /* Preferred BITS for this memory size */
X# ifndef BITS
X# define BITS PBITS
X# endif
X#endif /* PBITS */
X
X#if BITS == 16
X# define HSIZE 69001 /* 95% occupancy */
X#endif
X#if BITS == 15
X# define HSIZE 35023 /* 94% occupancy */
X#endif
X#if BITS == 14
X# define HSIZE 18013 /* 91% occupancy */
X#endif
X#if BITS == 13
X# define HSIZE 9001 /* 91% occupancy */
X#endif
X#if BITS <= 12
X# define HSIZE 5003 /* 80% occupancy */
X#endif
X
X#ifdef M_XENIX /* Stupid compiler can't handle arrays with */
X# if BITS == 16 /* more than 65535 bytes - so we fake it */
X# define XENIX_16
X# else
X# if BITS > 13 /* Code only handles BITS = 12, 13, or 16 */
X# define BITS 13
X# endif
X# endif
X#endif
X
X/*
X * a code_int must be able to hold 2**BITS values of type int, and also -1
X */
X#if BITS > 15
Xtypedef long int code_int;
X#else
Xtypedef int code_int;
X#endif
X
X#ifdef SIGNED_COMPARE_SLOW
Xtypedef unsigned long int count_int;
Xtypedef unsigned short int count_short;
X#else
Xtypedef long int count_int;
X#endif
X
X#ifdef NO_UCHAR
X typedef char char_type;
X#else
X typedef unsigned char char_type;
X#endif /* UCHAR */
Xchar_type magic_header[] = { "\037\235" }; /* 1F 9D */
X
X/* Defines for third byte of header */
X#define BIT_MASK 0x1f
X#define BLOCK_MASK 0x80
X/* Masks 0x40 and 0x20 are free. I think 0x20 should mean that there is
X a fourth header byte (for expansion).
X*/
X#define INIT_BITS 9 /* initial number of bits/code */
X
X/*
X * compress.c - File compression ala IEEE Computer, June 1984.
X *
X * Authors: Spencer W. Thomas (decvax!harpo!utah-cs!utah-gr!thomas)
X * Jim McKie (decvax!mcvax!jim)
X * Steve Davies (decvax!vax135!petsd!peora!srd)
X * Ken Turkowski (decvax!decwrl!turtlevax!ken)
X * James A. Woods (decvax!ihnp4!ames!jaw)
X * Joe Orost (decvax!vax135!petsd!joe)
X *
X * $Header: compress.c,v 4.0 85/07/30 12:50:00 joe Release $
X * $Log: compress.c,v $
X * Revision 4.1 85/12/02 Kent Williams
X * Ported to AZTEC C86 under MSDOS
X * Changed appending a ".Z" to just "Z" so that MSDOS won't choke
X * changed getchar and putchar to getc(stdin) and putc(c,stdout) to
X * suppress cr/nl mapping and hi bit masking
X *
X * Revision 4.0 85/07/30 12:50:00 joe
X * Removed ferror() calls in output routine on every output except first.
X * Prepared for release to the world.
X *
X * Revision 3.6 85/07/04 01:22:21 joe
X * Remove much wasted storage by overlaying hash table with the tables
X * used by decompress: tab_suffix[1<<BITS], stack[8000]. Updated USERMEM
X * computations. Fixed dump_tab() DEBUG routine.
X *
X * Revision 3.5 85/06/30 20:47:21 jaw
X * Change hash function to use exclusive-or. Rip out hash cache. These
X * speedups render the megamemory version defunct, for now. Make decoder
X * stack global. Parts of the RCS trunks 2.7, 2.6, and 2.1 no longer apply.
X *
X * Revision 3.4 85/06/27 12:00:00 ken
X * Get rid of all floating-point calculations by doing all compression ratio
X * calculations in fixed point.
X *
X * Revision 3.3 85/06/24 21:53:24 joe
X * Incorporate portability suggestion for M_XENIX. Got rid of text on #else
X * and #endif lines. Cleaned up #ifdefs for vax and interdata.
X *
X * Revision 3.2 85/06/06 21:53:24 jaw
X * Incorporate portability suggestions for Z8000, IBM PC/XT from mailing list.
X * Default to "quiet" output (no compression statistics).
X *
X * Revision 3.1 85/05/12 18:56:13 jaw
X * Integrate decompress() stack speedups (from early pointer mods by McKie).
X * Repair multi-file USERMEM gaffe. Unify 'force' flags to mimic semantics
X * of SVR2 'pack'. Streamline block-compress table clear logic. Increase
X * output byte count by magic number size.
X *
X * Revision 3.0 84/11/27 11:50:00 petsd!joe
X * Set HSIZE depending on BITS. Set BITS depending on USERMEM. Unrolled
X * loops in clear routines. Added "-C" flag for 2.0 compatibility. Used
X * unsigned compares on Perkin-Elmer. Fixed foreground check.
X *
X * Revision 2.7 84/11/16 19:35:39 ames!jaw
X * Cache common hash codes based on input statistics; this improves
X * performance for low-density raster images. Pass on #ifdef bundle
X * from Turkowski.
X *
X * Revision 2.6 84/11/05 19:18:21 ames!jaw
X * Vary size of hash tables to reduce time for small files.
X * Tune PDP-11 hash function.
X *
X * Revision 2.5 84/10/30 20:15:14 ames!jaw
X * Junk chaining; replace with the simpler (and, on the VAX, faster)
X * double hashing, discussed within. Make block compression standard.
X *
X * Revision 2.4 84/10/16 11:11:11 ames!jaw
X * Introduce adaptive reset for block compression, to boost the rate
X * another several percent. (See mailing list notes.)
X *
X * Revision 2.3 84/09/22 22:00:00 petsd!joe
X * Implemented "-B" block compress. Implemented REVERSE sorting of tab_next.
X * Bug fix for last bits. Changed fwrite to putc loop everywhere.
X *
X * Revision 2.2 84/09/18 14:12:21 ames!jaw
X * Fold in news changes, small machine typedef from thomas,
X * #ifdef interdata from joe.
X *
X * Revision 2.1 84/09/10 12:34:56 ames!jaw
X * Configured fast table lookup for 32-bit machines.
X * This cuts user time in half for b <= FBITS, and is useful for news batching
X * from VAX to PDP sites. Also sped up decompress() [fwrite->putc] and
X * added signal catcher [plus beef in writeerr()] to delete effluvia.
X *
X * Revision 2.0 84/08/28 22:00:00 petsd!joe
X * Add check for foreground before prompting user. Insert maxbits into
X * compressed file. Force file being uncompressed to end with ".Z".
X * Added "-c" flag and "zcat". Prepared for release.
X *
X * Revision 1.10 84/08/24 18:28:00 turtlevax!ken
X * Will only compress regular files (no directories), added a magic number
X * header (plus an undocumented -n flag to handle old files without headers),
X * added -f flag to force overwriting of possibly existing destination file,
X * otherwise the user is prompted for a response. Will tack on a .Z to a
X * filename if it doesn't have one when decompressing. Will only replace
X * file if it was compressed.
X *
X * Revision 1.9 84/08/16 17:28:00 turtlevax!ken
X * Removed scanargs(), getopt(), added .Z extension and unlimited number of
X * filenames to compress. Flags may be clustered (-Ddvb12) or separated
X * (-D -d -v -b 12), or combination thereof. Modes and other status is
X * copied with copystat(). -O bug for 4.2 seems to have disappeared with
X * 1.8.
X *
X * Revision 1.8 84/08/09 23:15:00 joe
X * Made it compatible with vax version, installed jim's fixes/enhancements
X *
X * Revision 1.6 84/08/01 22:08:00 joe
X * Sped up algorithm significantly by sorting the compress chain.
X *
X * Revision 1.5 84/07/13 13:11:00 srd
X * Added C version of vax asm routines. Changed structure to arrays to
X * save much memory. Do unsigned compares where possible (faster on
X * Perkin-Elmer)
X *
X * Revision 1.4 84/07/05 03:11:11 thomas
X * Clean up the code a little and lint it. (Lint complains about all
X * the regs used in the asm, but I'm not going to "fix" this.)
X *
X * Revision 1.3 84/07/05 02:06:54 thomas
X * Minor fixes.
X *
X * Revision 1.2 84/07/05 00:27:27 thomas
X * Add variable bit length output.
X *
X */
Xstatic char rcs_ident[] = "$Header: compress.c,v 4.1 85/12/05 09:00:00 kent Release $";
X
X#include <stdio.h>
X#include <ctype.h>
X
X#ifndef METAWARE
X#include <signal.h>
X#endif
X
X#ifndef AZTEC86
X#include <sys/types.h>
X#include <sys/stat.h>
X#else
X/* stuff defined for Aztec compiler */
X#ifndef MINIX
X#define PCDOS
X/* MINIX can handle full-length filenames, DOS can't */
X/* also, MINIX has full stat capability */
X#endif
X
X#include <stat.h>
X#ifndef METAWARE
X#ifndef MINIX
X/* MINIX signal.h includes definition of signal */
Xvoid (*signal())();
X#endif
XFILE *freopen();
X#endif
X#endif
X
X#ifdef PCDOS
X#define DOTZ "Z"
X#else
X#define DOTZ ".Z"
X#endif
X
X#define ARGVAL() (*++(*argv) || (--argc && *++argv))
X
Xint n_bits; /* number of bits/code */
Xint maxbits = BITS; /* user settable max # bits/code */
Xcode_int maxcode; /* maximum code, given n_bits */
Xcode_int maxmaxcode = 1 << BITS; /* should NEVER generate this code */
X#ifdef COMPATIBLE /* But wrong! */
X# define MAXCODE(n_bits) (1 << (n_bits) - 1)
X#else
X# define MAXCODE(n_bits) ((1 << (n_bits)) - 1)
X#endif /* COMPATIBLE */
X
X#ifdef XENIX_16
Xcount_int htab0[8192];
Xcount_int htab1[8192];
Xcount_int htab2[8192];
Xcount_int htab3[8192];
Xcount_int htab4[8192];
Xcount_int htab5[8192];
Xcount_int htab6[8192];
Xcount_int htab7[8192];
Xcount_int htab8[HSIZE-65536];
Xcount_int * htab[9] = {
X htab0, htab1, htab2, htab3, htab4, htab5, htab6, htab7, htab8 };
X#define htabof(i) (htab[(i) >> 13][(i) & 0x1fff])
Xunsigned short code0tab[16384];
Xunsigned short code1tab[16384];
Xunsigned short code2tab[16384];
Xunsigned short code3tab[16384];
Xunsigned short code4tab[16384];
Xunsigned short * codetab[5] = {
X code0tab, code1tab, code2tab, code3tab, code4tab };
X
X#define codetabof(i) (codetab[(i) >> 14][(i) & 0x3fff])
X
X#else /* Normal machine */
X
X#ifndef AZTEC86
X count_int htab [HSIZE];
X unsigned short codetab [HSIZE];
X#else
X count_int *htab;
X unsigned short *codetab;
X# define HTABSIZE ((unsigned)(HSIZE*sizeof(count_int)))
X# define CODETABSIZE ((unsigned)(HSIZE*sizeof(unsigned short)))
X
X#endif
X#define htabof(i) htab[i]
X#define codetabof(i) codetab[i]
X#endif /* XENIX_16 */
Xcode_int hsize = HSIZE; /* for dynamic table sizing */
Xcount_int fsize;
X
X/*
X * To save much memory, we overlay the table used by compress() with those
X * used by decompress(). The tab_prefix table is the same size and type
X * as the codetab. The tab_suffix table needs 2**BITS characters. We
X * get this from the beginning of htab. The output stack uses the rest
X * of htab, and contains characters. There is plenty of room for any
X * possible stack (stack used to be 8000 characters).
X */
X
X#define tab_prefixof(i) codetabof(i)
X#ifdef XENIX_16
X# define tab_suffixof(i) ((char_type *)htab[(i)>>15])[(i) & 0x7fff]
X# define de_stack ((char_type *)(htab2))
X#else /* Normal machine */
X# define tab_suffixof(i) ((char_type *)(htab))[i]
X# define de_stack ((char_type *)&tab_suffixof(1<<BITS))
X#endif /* XENIX_16 */
X
Xcode_int free_ent = 0; /* first unused entry */
Xint exit_stat = 0;
X
Xcode_int getcode();
X
Xvoid Usage() {
X#ifdef DEBUG
Xfprintf(stderr,"Usage: compress [-dDVfc] [-b maxbits] [file ...]\n");
X}
Xint debug = 0;
X#else
Xfprintf(stderr,"Usage: compress [-dfvcV] [-b maxbits] [file ...]\n");
X}
X#endif /* DEBUG */
Xint nomagic = 0; /* Use a 3-byte magic number header, unless old file */
Xint zcat_flg = 0; /* Write output on stdout, suppress messages */
Xint quiet = 0; /* don't tell me about compression */
X
X/*
X * block compression parameters -- after all codes are used up,
X * and compression rate changes, start over.
X */
Xint block_compress = BLOCK_MASK;
Xint clear_flg = 0;
Xlong int ratio = 0;
X#define CHECK_GAP 10000 /* ratio check interval */
Xcount_int checkpoint = CHECK_GAP;
X/*
X * the next two codes should not be changed lightly, as they must not
X * lie within the contiguous general code space.
X */
X#define FIRST 257 /* first free entry */
X#define CLEAR 256 /* table clear output code */
X
Xint force = 0;
Xchar ofname [100];
X#ifdef DEBUG
Xint verbose = 0;
X#endif /* DEBUG */
X
X#ifndef METAWARE
X#ifdef AZTEC86
Xvoid
X#else
Xint
X#endif
X(*bgnd_flag)();
X#endif
X
Xint do_decomp = 0;
X
X/*****************************************************************
X * TAG( main )
X *
X * Algorithm from "A Technique for High Performance Data Compression",
X * Terry A. Welch, IEEE Computer Vol 17, No 6 (June 1984), pp 8-19.
X *
X * Usage: compress [-dfvc] [-b bits] [file ...]
X * Inputs:
X * -d: If given, decompression is done instead.
X *
X * -c: Write output on stdout, don't remove original.
X *
X * -b: Parameter limits the max number of bits/code.
X *
X * -f: Forces output file to be generated, even if one already
X * exists, and even if no space is saved by compressing.
X * If -f is not used, the user will be prompted if stdin is
X * a tty, otherwise, the output file will not be overwritten.
X *
X * -v: Write compression statistics
X *
X * file ...: Files to be compressed. If none specified, stdin
X * is used.
X * Outputs:
X * file.Z: Compressed form of file with same mode, owner, and utimes
X * or stdout (if stdin used as input)
X *
X * Assumptions:
X * When filenames are given, replaces with the compressed version
X * (.Z suffix) only if the file decreases in size.
X * Algorithm:
X * Modified Lempel-Ziv method (LZW). Basically finds common
X * substrings and replaces them with a variable size code. This is
X * deterministic, and can be done on the fly. Thus, the decompression
X * procedure needs no input table, but tracks the way the table was built.
X */
X
Xvoid main( argc, argv )
XREGISTER int argc; char **argv;
X{
X int overwrite = 0; /* Do not overwrite unless given -f flag */
X char tempname[100];
X char **filelist, **fileptr;
X char *cp;extern char *strrchr(), *malloc();
X struct stat statbuf;
X#ifndef METAWARE
X extern void onintr(), oops();
X if ( (bgnd_flag = signal ( SIGINT, SIG_IGN )) != SIG_IGN ) {
X signal ( SIGINT, onintr );
X signal ( SIGSEGV, oops );
X }
X#endif
X#ifdef AZTEC86
X#ifdef METAWARE
X _setmode(NULL,_ALL_FILES_BINARY);
X _setmode(stdin,_BINARY);
X _setmode(stdout,_BINARY);
X _setmode(stderr,_TEXT);
X#endif
X if (NULL == (htab = (count_int *)malloc(HTABSIZE)))
X {
X fprintf(stderr,"Can't allocate htab\n");
X exit(1);
X }
X if (NULL == (codetab = (unsigned short *)malloc(CODETABSIZE)))
X {
X fprintf(stderr,"Can't allocate codetab\n");
X exit(1);
X }
X#endif
X#ifdef COMPATIBLE
X nomagic = 1; /* Original didn't have a magic number */
X#endif /* COMPATIBLE */
X
X filelist = fileptr = (char **)(malloc((unsigned)(argc * sizeof(*argv))));
X *filelist = NULL;
X
X if((cp = strrchr(argv[0], '/')) != 0) {
X cp++;
X } else {
X cp = argv[0];
X }
X if(strcmp(cp, "uncompress") == 0) {
X do_decomp = 1;
X } else if(strcmp(cp, "zcat") == 0) {
X do_decomp = 1;
X zcat_flg = 1;
X }
X
X#ifdef BSD4_2
X /* 4.2BSD dependent - take it out if not */
X setlinebuf( stderr );
X#endif /* BSD4_2 */
X
X /* Argument Processing
X * All flags are optional.
X * -D => debug
X * -V => print Version; debug verbose
X * -d => do_decomp
X * -v => unquiet
X * -f => force overwrite of output file
X * -n => no header: useful to uncompress old files
X * -b maxbits => maxbits. If -b is specified, then maxbits MUST be
X * given also.
X * -c => cat all output to stdout
X * -C => generate output compatible with compress 2.0.
X * if a string is left, must be an input filename.
X */
X for (argc--, argv++; argc > 0; argc--, argv++)
X {
X if (**argv == '-')
X { /* A flag argument */
X while (*++(*argv))
X { /* Process all flags in this arg */
X switch (**argv)
X {
X#ifdef DEBUG
X case 'D':
X debug = 1;
X break;
X case 'V':
X verbose = 1;
X version();
X break;
X#else
X case 'V':
X version();
X break;
X#endif /* DEBUG */
X case 'v':
X quiet = 0;
X break;
X case 'd':
X do_decomp = 1;
X break;
X case 'f':
X case 'F':
X overwrite = 1;
X force = 1;
X break;
X case 'n':
X nomagic = 1;
X break;
X case 'C':
X block_compress = 0;
X break;
X case 'b':
X if (!ARGVAL())
X {
X fprintf(stderr, "Missing maxbits\n");
X Usage();
X exit(1);
X }
X maxbits = atoi(*argv);
X goto nextarg;
X case 'c':
X zcat_flg = 1;
X break;
X case 'q':
X quiet = 1;
X break;
X default:
X fprintf(stderr, "Unknown flag: '%c'; ", **argv);
X Usage();
X exit(1);
X }
X }
X }
X else
X { /* Input file name */
X *fileptr++ = *argv; /* Build input file list */
X *fileptr = NULL;
X /* process nextarg; */
X }
X nextarg: continue;
X }
X
X if(maxbits < INIT_BITS) maxbits = INIT_BITS;
X if (maxbits > BITS) maxbits = BITS;
X maxmaxcode = 1 << maxbits;
X
X if (*filelist != NULL)
X {
X for (fileptr = filelist; *fileptr; fileptr++)
X {
X exit_stat = 0;
X if (do_decomp != 0)
X { /* DECOMPRESSION */
X /* Check for .Z suffix */
X#ifndef PCDOS
X if (strcmp(*fileptr + strlen(*fileptr) - 2, DOTZ) != 0)
X#else
X if (strcmp(*fileptr + strlen(*fileptr) - 1, DOTZ) != 0)
X#endif
X {
X /* No .Z: tack one on */
X strcpy(tempname, *fileptr);
X#ifndef PCDOS
X strcat(tempname, DOTZ);
X#else
X /* either tack one on or replace last character */
X {
X char *dot;extern char *strchr();
X if (NULL == (dot = strchr(tempname,'.')))
X {
X strcat(tempname,".Z");
X }
X else
X /* if there is a dot then either tack a z on
X or replace last character */
X {
X if (strlen(dot) < 4)
X strcat(tempname,DOTZ);
X else
X dot[3] = 'Z';
X }
X }
X#endif
X *fileptr = tempname;
X }
X /* Open input file */
X if ((freopen(*fileptr, "r", stdin)) == NULL)
X {
X perror(*fileptr); continue;
X }
X /* Check the magic number */
X if (nomagic == 0)
X {
X unsigned magic1, magic2;
X if (((magic1 = getc(stdin)) != (magic_header[0] & 0xFF))
X || ((magic2 = getc(stdin)) != (magic_header[1] & 0xFF)))
X {
X fprintf(stderr,
X "%s: not in compressed format %x %x\n",
X *fileptr,magic1,magic2);
X continue;
X }
X maxbits = getc(stdin); /* set -b from file */
X block_compress = maxbits & BLOCK_MASK;
X maxbits &= BIT_MASK;
X maxmaxcode = 1 << maxbits;
X if(maxbits > BITS)
X {
X fprintf(stderr,
X "%s: compressed with %d bits, can only handle %d bits\n",
X *fileptr, maxbits, BITS);
X continue;
X }
X }
X /* Generate output filename */
X strcpy(ofname, *fileptr);
X#ifndef PCDOS
X ofname[strlen(*fileptr) - 2] = '\0'; /* Strip off .Z */
X#else
X /* kludge to handle various common three character extension */
X {
X char *dot; extern char *strchr();
X char fixup = '\0';
X /* first off, map name to upper case */
X for (dot = ofname; *dot; dot++)
X *dot = toupper(*dot);
X if (NULL == (dot = strchr(ofname,'.')))
X {
X fprintf(stderr,"Bad filename %s\n",ofname);
X exit(1);
X }
X if (strlen(dot) == 4)
X /* we got three letter extensions */
X {
X if (strcmp(dot,".EXZ") == 0)
X fixup = 'E';
X else if (strcmp(dot,".COZ") == 0)
X fixup = 'M';
X else if (strcmp(dot,".BAZ") == 0)
X fixup = 'S';
X else if (strcmp(dot,".OBZ") == 0)
X fixup = 'J';
X else if (strcmp(dot,".SYZ") == 0)
X fixup = 'S';
X else if (strcmp(dot,".DOZ") == 0)
X fixup = 'C';
X
X }
X /* replace the Z */
X ofname[strlen(*fileptr) - 1] = fixup;
X }
X#endif
X } else
X { /* COMPRESSION */
X if (strcmp(*fileptr + strlen(*fileptr) - 2, DOTZ) == 0)
X {
X fprintf(stderr, "%s: already has .Z suffix -- no change\n",
X *fileptr);
X continue;
X }
X /* Open input file */
X if ((freopen(*fileptr, "r", stdin)) == NULL)
X {
X perror(*fileptr); continue;
X }
X (void)stat( *fileptr, &statbuf );
X fsize = (long) statbuf.st_size;
X /*
X * tune hash table size for small files -- ad hoc,
X * but the sizes match earlier #defines, which
X * serve as upper bounds on the number of output codes.
X */
X hsize = HSIZE; /*lint -e506 -e712 */
X if ( fsize < (1 << 12) )
X hsize = min ( 5003, HSIZE );
X else if ( fsize < (1 << 13) )
X hsize = min ( 9001, HSIZE );
X else if ( fsize < (1 << 14) )
X hsize = min ( 18013, HSIZE );
X else if ( fsize < (1 << 15) )
X hsize = min ( 35023, HSIZE );
X else if ( fsize < 47000 )
X hsize = min ( 50021, HSIZE ); /*lint +e506 +e712 */
X
X /* Generate output filename */
X strcpy(ofname, *fileptr);
X#ifndef BSD4_2 /* Short filenames */
X if ((cp=strrchr(ofname,'/')) != NULL)
X cp++;
X else
X cp = ofname;
X if (strlen(cp) > 12)
X {
X fprintf(stderr,"%s: filename too long to tack on .Z\n",cp);
X continue;
X }
X#ifdef PCDOS
X else
X {
X /* either tack one on or replace last character */
X char *dot;extern char *strchr();
X if (NULL == (dot = strchr(cp,'.')))
X {
X strcat(cp,".Z");
X }
X else
X /* if there is a dot then either tack a z on
X or replace last character */
X {
X if (strlen(dot) < 4)
X strcat(cp,DOTZ);
X else
X dot[3] = 'Z';
X }
X }
X#endif
X#endif /* BSD4_2 Long filenames allowed */
X#ifndef PCDOS
X /* PCDOS takes care of this above */
X strcat(ofname, DOTZ);
X#endif
X }
X /* Check for overwrite of existing file */
X if (overwrite == 0 && zcat_flg == 0)
X {
X if (stat(ofname, &statbuf) == 0)
X {
X char response[2];
X response[0] = 'n';
X fprintf(stderr, "%s already exists;", ofname);
X if (foreground())
X {
X fprintf(stderr,
X " do you wish to overwrite %s (y or n)? ", ofname);
X fflush(stderr);
X (void)read(2, response, 2);
X while (response[1] != '\n')
X {
X if (read(2, response+1, 1) < 0)
X { /* Ack! */
X perror("stderr");
X break;
X }
X }
X }
X if (response[0] != 'y')
X {
X fprintf(stderr, "\tnot overwritten\n");
X continue;
X }
X }
X }
X if(zcat_flg == 0)
X { /* Open output file */
X if (freopen(ofname, "w", stdout) == NULL)
X {
X perror(ofname);
X continue;
X }
X if(!quiet)
X fprintf(stderr, "%s: ", *fileptr);
X }
X
X /* Actually do the compression/decompression */
X if (do_decomp == 0)
X compress();
X#ifndef DEBUG
X else
X decompress();
X#else
X else if (debug == 0)
X decompress();
X else
X printcodes();
X if (verbose)
X dump_tab();
X#endif /* DEBUG */
X if(zcat_flg == 0)
X {
X copystat(*fileptr, ofname); /* Copy stats */
X if((exit_stat == 1) || (!quiet))
X putc('\n', stderr);
X }
X }
X } else
X { /* Standard input */
X if (do_decomp == 0)
X {
X compress();
X#ifdef DEBUG
X if(verbose) dump_tab();
X#endif /* DEBUG */
X if(!quiet)
X putc('\n', stderr);
X } else
X {
X /* Check the magic number */
X if (nomagic == 0)
X {
X if ((getc(stdin)!=(magic_header[0] & 0xFF))
X || (getc(stdin)!=(magic_header[1] & 0xFF)))
X {
X fprintf(stderr, "stdin: not in compressed format\n");
X exit(1);
X }
X maxbits = getc(stdin); /* set -b from file */
X block_compress = maxbits & BLOCK_MASK;
X maxbits &= BIT_MASK;
X maxmaxcode = 1 << maxbits;
X fsize = 100000; /* assume stdin large for USERMEM */
X if(maxbits > BITS)
X {
X fprintf(stderr,
X "stdin: compressed with %d bits, can only handle %d bits\n",
X maxbits, BITS);
X exit(1);
X }
X }
X#ifndef DEBUG
X decompress();
X#else
X if (debug == 0) decompress();
X else printcodes();
X if (verbose) dump_tab();
X#endif /* DEBUG */
X }
X }
X exit(exit_stat);
X}
X
Xstatic int offset;
Xlong int in_count = 1; /* length of input */
Xlong int bytes_out; /* length of compressed output */
Xlong int out_count = 0; /* # of codes output (for debugging) */
X
X/*
X * compress stdin to stdout
X *
X * Algorithm: use open addressing double hashing (no chaining) on the
X * prefix code / next character combination. We do a variant of Knuth's
X * algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime
X * secondary probe. Here, the modular division first probe is gives way
X * to a faster exclusive-or manipulation. Also do block compression with
X * an adaptive reset, whereby the code table is cleared when the compression
X * ratio decreases, but after the table fills. The variable-length output
X * codes are re-sized at this point, and a special CLEAR code is generated
X * for the decompressor. Late addition: construct the table according to
X * file size for noticeable speed improvement on small files. Please direct
X * questions about this implementation to ames!jaw.
X */
X
Xvoid compress()
X{
X REGISTER long fcode;
X REGISTER code_int i = 0;
X REGISTER int c;
X REGISTER code_int ent;
X#ifdef XENIX_16
X REGISTER code_int disp;
X#else /* Normal machine */
X REGISTER int disp;
X#endif
X REGISTER code_int hsize_reg;
X REGISTER int hshift;
X
X#ifndef COMPATIBLE
X if (nomagic == 0)
X {
X putc(magic_header[0],stdout);
X putc(magic_header[1],stdout);
X putc((char)(maxbits | block_compress),stdout);
X if(ferror(stdout))
X writeerr();
X }
X#endif /* COMPATIBLE */
X
X offset = 0;
X bytes_out = 3; /* includes 3-byte header mojo */
X out_count = 0;
X clear_flg = 0;
X ratio = 0;
X in_count = 1;
X checkpoint = CHECK_GAP;
X maxcode = MAXCODE(n_bits = INIT_BITS);
X free_ent = ((block_compress) ? FIRST : 256 );
X
X ent = getc(stdin);
X
X hshift = 0;
X for ( fcode = (long) hsize; fcode < 65536L; fcode *= 2L )
X hshift++;
X hshift = 8 - hshift; /* set hash code range bound */
X
X hsize_reg = hsize;
X cl_hash( (count_int) hsize_reg); /* clear hash table */
X
X#ifdef SIGNED_COMPARE_SLOW
X while ( (c = getc(stdin)) != (unsigned) EOF )
X#else
X while ( (c = getc(stdin)) != EOF )
X#endif
X {
X in_count++;
X fcode = (long) (((long) c << maxbits) + ent);
X i = ((c << hshift) ^ ent); /* xor hashing */
X
X if ( htabof (i) == fcode )
X {
X ent = codetabof (i);
X continue;
X } else if ( (long)htabof (i) < 0 ) /* empty slot */
X goto nomatch;
X disp = hsize_reg - i; /* secondary hash (after G. Knott) */
X if ( i == 0 )
X disp = 1;
Xprobe:
X if ( (i -= disp) < 0 )
X i += hsize_reg;
X
X if ( htabof (i) == fcode )
X {
X ent = codetabof (i);
X continue;
X }
X if ( (long)htabof (i) > 0 )
X goto probe;
Xnomatch:
X output ( (code_int) ent );
X out_count++;
X ent = c;
X#ifdef SIGNED_COMPARE_SLOW
X if ( (unsigned) free_ent < (unsigned) maxmaxcode)
X#else
X if ( free_ent < maxmaxcode )
X#endif
X {
X codetabof (i) = free_ent++; /* code -> hashtable */
X htabof (i) = fcode;
X }
X else if ( (count_int)in_count >= checkpoint && block_compress )
X cl_block ();
X }
X /*
X * Put out the final code.
X */
X output( (code_int)ent );
X out_count++;
X output( (code_int)-1 );
X
X /*
X * Print out stats on stderr
X */
X if(zcat_flg == 0 && !quiet)
X {
X#ifdef DEBUG
X fprintf( stderr,
X "%ld chars in, %ld codes (%ld bytes) out, compression factor: ",
X in_count, out_count, bytes_out );
X prratio( stderr, in_count, bytes_out );
X fprintf( stderr, "\n");
X fprintf( stderr, "\tCompression as in compact: " );
X prratio( stderr, in_count-bytes_out, in_count );
X fprintf( stderr, "\n");
X fprintf( stderr, "\tLargest code (of last block) was %d (%d bits)\n",
X free_ent - 1, n_bits );
X#else /* !DEBUG */
X fprintf( stderr, "Compression: " );
X prratio( stderr, in_count-bytes_out, in_count );
X#endif /* DEBUG */
X }
X if(bytes_out > in_count) /* exit(2) if no savings */
X exit_stat = 2;
X return;
X}
X
X/*****************************************************************
X * TAG( output )
X *
X * Output the given code.
X * Inputs:
X * code: A n_bits-bit integer. If == -1, then EOF. This assumes
X * that n_bits =< (long)wordsize - 1.
X * Outputs:
X * Outputs code to the file.
X * Assumptions:
X * Chars are 8 bits long.
X * Algorithm:
X * Maintain a BITS character long buffer (so that 8 codes will
X * fit in it exactly). Use the VAX insv instruction to insert each
X * code in turn. When the buffer fills up empty it and start over.
X */
X
Xstatic char buf[BITS];
X
X#ifndef vax
Xchar_type lmask[9] = {0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80, 0x00};
Xchar_type rmask[9] = {0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff};
X#endif /* vax */
Xvoid output( code )
Xcode_int code;
X{
X#ifdef DEBUG
X static int col = 0;
X#endif /* DEBUG */
X
X /*
X * On the VAX, it is important to have the REGISTER declarations
X * in exactly the order given, or the asm will break.
X */
X REGISTER int r_off = offset, bits= n_bits;
X REGISTER char * bp = buf;
X#ifndef BREAKHIGHC
X#ifdef METAWARE
X int temp;
X#endif
X#endif
X#ifdef DEBUG
X if ( verbose )
X fprintf( stderr, "%5d%c", code,
X (col+=6) >= 74 ? (col = 0, '\n') : ' ' );
X#endif /* DEBUG */
X if ( code >= 0 )
X {
X#ifdef vax
X /* VAX DEPENDENT!! Implementation on other machines is below.
X *
X * Translation: Insert BITS bits from the argument starting at
X * offset bits from the beginning of buf.
X */
X 0; /* Work around for pcc -O bug with asm and if stmt */
X asm( "insv 4(ap),r11,r10,(r9)" );
X#else /* not a vax */
X/*
X * byte/bit numbering on the VAX is simulated by the following code
X */
X /*
X * Get to the first byte.
X */
X bp += (r_off >> 3);
X r_off &= 7;
X /*
X * Since code is always >= 8 bits, only need to mask the first
X * hunk on the left.
X */
X#ifndef BREAKHIGHC
X#ifdef METAWARE
X *bp &= rmask[r_off];
X temp = (code << r_off) & lmask[r_off];
X *bp |= temp;
X#else
X *bp = (*bp & rmask[r_off]) | (code << r_off) & lmask[r_off];
X#endif
X#else
X *bp = (*bp & rmask[r_off]) | (code << r_off) & lmask[r_off];
X#endif
X bp++;
X bits -= (8 - r_off);
X code >>= (8 - r_off);
X /* Get any 8 bit parts in the middle (<=1 for up to 16 bits). */
X if ( bits >= 8 )
X {
X *bp++ = code;
X code >>= 8;
X bits -= 8;
X }
X /* Last bits. */
X if(bits)
X *bp = code;
X#endif /* vax */
X offset += n_bits;
X if ( offset == (n_bits << 3) )
X {
X bp = buf;
X bits = n_bits;
X bytes_out += bits;
X do
X putc(*bp++,stdout);
X while(--bits);
X offset = 0;
X }
X
X /*
X * If the next entry is going to be too big for the code size,
X * then increase it, if possible.
X */
X if ( free_ent > maxcode || (clear_flg > 0))
X {
X /*
X * Write the whole buffer, because the input side won't
X * discover the size increase until after it has read it.
X */
X if ( offset > 0 )
X {
X if( fwrite( buf, 1, n_bits, stdout ) != n_bits)
X writeerr();
X bytes_out += n_bits;
X }
X offset = 0;
X
X if ( clear_flg )
X {
X maxcode = MAXCODE (n_bits = INIT_BITS);
X clear_flg = 0;
X }
X else
X {
X n_bits++;
X if ( n_bits == maxbits )
X maxcode = maxmaxcode;
X else
X maxcode = MAXCODE(n_bits);
X }
X#ifdef DEBUG
X if ( debug )
X {
X fprintf( stderr, "\nChange to %d bits\n", n_bits );
X col = 0;
X }
X#endif /* DEBUG */
X }
X } else
X {
X /*
X * At EOF, write the rest of the buffer.
X */
X if ( offset > 0 )
X fwrite( buf, 1, (offset + 7) / 8, stdout );
X bytes_out += (offset + 7) / 8;
X offset = 0;
X fflush( stdout );
X#ifdef DEBUG
X if ( verbose )
X fprintf( stderr, "\n" );
X#endif /* DEBUG */
X if( ferror( stdout ) )
X writeerr();
X }
X}
X/*
X * Decompress stdin to stdout. This routine adapts to the codes in the
X * file building the "string" table on-the-fly; requiring no table to
X * be stored in the compressed file. The tables used herein are shared
X * with those of the compress() routine. See the definitions above.
X */
X
Xvoid decompress() {
X REGISTER char_type *stackp;
X REGISTER int finchar;
X REGISTER code_int code, oldcode, incode;
X
X /*
X * As above, initialize the first 256 entries in the table.
X */
X maxcode = MAXCODE(n_bits = INIT_BITS);
X for ( code = 255; code >= 0; code-- ) {
X tab_prefixof(code) = 0;
X tab_suffixof(code) = (char_type)code;
X }
X free_ent = ((block_compress) ? FIRST : 256 );
X
X finchar = oldcode = getcode();
X if(oldcode == -1) /* EOF already? */
X return; /* Get out of here */
X putc( (char)finchar,stdout ); /* first code must be 8 bits = char */
X if(ferror(stdout)) /* Crash if can't write */
X writeerr();
X stackp = de_stack;
X
X while ( (code = getcode()) > -1 ) {
X
X if ( (code == CLEAR) && block_compress ) {
X for ( code = 255; code >= 0; code-- )
X tab_prefixof(code) = 0;
X clear_flg = 1;
X free_ent = FIRST - 1;
X if ( (code = getcode ()) == -1 ) /* O, untimely death! */
X break;
X }
X incode = code;
X /*
X * Special case for KwKwK string.
X */
X if ( code >= free_ent ) {
X *stackp++ = finchar;
X code = oldcode;
X }
X
X /*
X * Generate output characters in reverse order
X */
X#ifdef SIGNED_COMPARE_SLOW
X while ( ((unsigned long)code) >= ((unsigned long)256) ) {
X#else
X while ( code >= 256 ) {
X#endif
X *stackp++ = tab_suffixof(code);
X code = tab_prefixof(code);
X }
X *stackp++ = finchar = tab_suffixof(code);
X
X /*
X * And put them out in forward order
X */
X do
X putc ( *--stackp ,stdout);
X while ( stackp > de_stack );
X
X /*
X * Generate the new entry.
X */
X if ( (code=free_ent) < maxmaxcode )
X {
X tab_prefixof(code) = (unsigned short)oldcode;
X tab_suffixof(code) = finchar;
X free_ent = code+1;
X }
X /*
X * Remember previous code.
X */
X oldcode = incode;
X }
X fflush( stdout );
X if(ferror(stdout))
X writeerr();
X}
X
X/*****************************************************************
X * TAG( getcode )
X *
X * Read one code from the standard input. If EOF, return -1.
X * Inputs:
X * stdin
X * Outputs:
X * code or -1 is returned.
X */
X
Xcode_int
Xgetcode()
X{
X /*
X * On the VAX, it is important to have the REGISTER declarations
X * in exactly the order given, or the asm will break.
X */
X REGISTER code_int code;
X static int offset = 0, size = 0;
X static char_type buf[BITS];
X REGISTER int r_off, bits;
X REGISTER char_type *bp = buf;
X
X if ( clear_flg > 0 || offset >= size || free_ent > maxcode )
X {
X /*
X * If the next entry will be too big for the current code
X * size, then we must increase the size. This implies reading
X * a new buffer full, too.
X */
X if ( free_ent > maxcode )
X {
X n_bits++;
X if ( n_bits == maxbits )
X maxcode = maxmaxcode; /* won't get any bigger now */
X else
X maxcode = MAXCODE(n_bits);
X }
X if ( clear_flg > 0)
X {
X maxcode = MAXCODE (n_bits = INIT_BITS);
X clear_flg = 0;
X }
X size = fread( buf, 1, n_bits, stdin );
X if ( size <= 0 )
X return -1; /* end of file */
X offset = 0;
X /* Round size down to integral number of codes */
X size = (size << 3) - (n_bits - 1);
X }
X r_off = offset;
X bits = n_bits;
X#ifdef vax
X asm( "extzv r10,r9,(r8),r11" );
X#else /* not a vax */
X /*
X * Get to the first byte.
X */
X bp += (r_off >> 3);
X r_off &= 7;
X /* Get first part (low order bits) */
X#ifdef NO_UCHAR
X code = ((*bp++ >> r_off) & rmask[8 - r_off]) & 0xff;
X#else
X code = (*bp++ >> r_off);
X#endif /* NO_UCHAR */
X bits -= (8 - r_off);
X r_off = 8 - r_off; /* now, offset into code word */
X /* Get any 8 bit parts in the middle (<=1 for up to 16 bits). */
X if ( bits >= 8 )
X {
X#ifdef NO_UCHAR
X code |= (*bp++ & 0xff) << r_off;
X#else
X code |= *bp++ << r_off;
X#endif /* NO_UCHAR */
X r_off += 8;
X bits -= 8;
X }
X /* high order bits. */
X code |= (*bp & rmask[bits]) << r_off;
X#endif /* vax */
X offset += n_bits;
X
X return code;
X}
X
X#ifndef AZTEC86
Xchar *
Xstrrchr(s, c) /* For those who don't have it in libc.a */
XREGISTER char *s, c;
X{
X char *p;
X for (p = NULL; *s; s++)
X if (*s == c)
X p = s;
X return(p);
X}
X#endif
X#ifdef MINIX
Xchar *
Xstrrchr(s, c) /* For those who don't have it in libc.a */
XREGISTER char *s, c;
X{
X char *p;
X for (p = NULL; *s; s++)
X if (*s == c)
X p = s;
X return(p);
X}
X#endif
X
X
X#ifndef METAWARE
X#ifdef DEBUG
Xprintcodes()
X{
X /*
X * Just print out codes from input file. For debugging.
X */
X code_int code;
X int col = 0, bits;
X
X bits = n_bits = INIT_BITS;
X maxcode = MAXCODE(n_bits);
X free_ent = ((block_compress) ? FIRST : 256 );
X while ( ( code = getcode() ) >= 0 ) {
X if ( (code == CLEAR) && block_compress ) {
X free_ent = FIRST - 1;
X clear_flg = 1;
X }
X else if ( free_ent < maxmaxcode )
X free_ent++;
X if ( bits != n_bits ) {
X fprintf(stderr, "\nChange to %d bits\n", n_bits );
X bits = n_bits;
X col = 0;
X }
X fprintf(stderr, "%5d%c", code, (col+=6) >= 74 ? (col = 0, '\n') : ' ' );
X }
X putc( '\n', stderr );
X exit( 0 );
X}
X#ifdef DEBUG2
Xcode_int sorttab[1<<BITS]; /* sorted pointers into htab */
X#define STACK_SIZE 500
Xstatic char stack[STACK_SIZE];
X/* dumptab doesn't use main stack now -prevents distressing crashes */
Xdump_tab() /* dump string table */
X{
X REGISTER int i, first;
X REGISTER ent;
X int stack_top = STACK_SIZE;
X REGISTER c;
X
X if(do_decomp == 0) { /* compressing */
X REGISTER int flag = 1;
X
X for(i=0; i<hsize; i++) { /* build sort pointers */
X if((long)htabof(i) >= 0) {
X sorttab[codetabof(i)] = i;
X }
X }
X first = block_compress ? FIRST : 256;
X for(i = first; i < free_ent; i++) {
X fprintf(stderr, "%5d: \"", i);
X stack[--stack_top] = '\n';
X stack[--stack_top] = '"'; /* " */
X stack_top = in_stack((int)(htabof(sorttab[i])>>maxbits)&0xff,
X stack_top);
X for(ent=htabof(sorttab[i]) & ((1<<maxbits)-1);
X ent > 256;
X ent=htabof(sorttab[ent]) & ((1<<maxbits)-1)) {
X stack_top = in_stack((int)(htabof(sorttab[ent]) >> maxbits),
X stack_top);
X }
X stack_top = in_stack(ent, stack_top);
X fwrite( &stack[stack_top], 1, STACK_SIZE-stack_top, stderr);
X stack_top = STACK_SIZE;
X }
X } else if(!debug) { /* decompressing */
X
X for ( i = 0; i < free_ent; i++ ) {
X ent = i;
X c = tab_suffixof(ent);
X if ( isascii(c) && isprint(c) )
X fprintf( stderr, "%5d: %5d/'%c' \"",
X ent, tab_prefixof(ent), c );
X else
X fprintf( stderr, "%5d: %5d/\\%03o \"",
X ent, tab_prefixof(ent), c );
X stack[--stack_top] = '\n';
X stack[--stack_top] = '"'; /* " */
X for ( ; ent != NULL;
X ent = (ent >= FIRST ? tab_prefixof(ent) : NULL) ) {
X stack_top = in_stack(tab_suffixof(ent), stack_top);
X }
X fwrite( &stack[stack_top], 1, STACK_SIZE - stack_top, stderr );
X stack_top = STACK_SIZE;
X }
X }
X}
X
Xint
Xin_stack(c, stack_top)
X REGISTER int c, stack_top;
X{
X if ( (isascii(c) && isprint(c) && c != '\\') || c == ' ' ) {
X stack[--stack_top] = c;
X } else {
X switch( c ) {
X case '\n': stack[--stack_top] = 'n'; break;
X case '\t': stack[--stack_top] = 't'; break;
X case '\b': stack[--stack_top] = 'b'; break;
X case '\f': stack[--stack_top] = 'f'; break;
X case '\r': stack[--stack_top] = 'r'; break;
X case '\\': stack[--stack_top] = '\\'; break;
X default:
X stack[--stack_top] = '0' + c % 8;
X stack[--stack_top] = '0' + (c / 8) % 8;
X stack[--stack_top] = '0' + c / 64;
X break;
X }
X stack[--stack_top] = '\\';
X }
X if (stack_top<0) {
X fprintf(stderr,"dump_tab stack overflow!!!\n");
X exit(1);
X }
X return stack_top;
X}
X#else
Xdump_tab() {}
X#endif /* DEBUG2 */
X#endif /* DEBUG */
X#endif /* METAWARE */
X
Xvoid writeerr()
X{
X perror ( ofname );
X unlink ( ofname );
X exit ( 1 );
X}
X
Xvoid copystat(ifname, ofname)
Xchar *ifname, *ofname;
X{
X struct stat statbuf;
X int mode;
X#ifndef AZTEC86
X time_t timep[2];
X#else
X unsigned long timep[2];
X#endif
X fclose(stdout);
X if (stat(ifname, &statbuf))
X { /* Get stat on input file */
X perror(ifname);
X return;
X }
X#ifndef PCDOS
X /* meddling with UNIX-style file modes */
X if ((statbuf.st_mode & S_IFMT/*0170000*/) != S_IFREG/*0100000*/)
X {
X if(quiet)
X fprintf(stderr, "%s: ", ifname);
X fprintf(stderr, " -- not a regular file: unchanged");
X exit_stat = 1;
X } else if (statbuf.st_nlink > 1)
X {
X if(quiet)
X fprintf(stderr, "%s: ", ifname);
X fprintf(stderr, " -- has %d other links: unchanged",
X statbuf.st_nlink - 1);
X exit_stat = 1;
X } else
X#endif
X if (exit_stat == 2 && (!force))
X { /* No compression: remove file.Z */
X if(!quiet)
X fprintf(stderr, " -- file unchanged");
X } else
X { /* ***** Successful Compression ***** */
X exit_stat = 0;
X#ifndef PCDOS
X mode = statbuf.st_mode & 07777;
X#else
X mode = statbuf.st_attr & 07777;
X#endif
X if (chmod(ofname, mode)) /* Copy modes */
X perror(ofname);
X#ifndef PCDOS
X chown(ofname, statbuf.st_uid, statbuf.st_gid); /* Copy ownership */
X timep[0] = statbuf.st_atime;
X timep[1] = statbuf.st_mtime;
X#else
X timep[0] = statbuf.st_mtime;
X timep[1] = statbuf.st_mtime;
X#endif
X utime(ofname, timep); /* Update last accessed and modified times */
X if (unlink(ifname)) /* Remove input file */
X perror(ifname);
X if(!quiet)
X fprintf(stderr, " -- replaced with %s", ofname);
X return; /* Successful return */
X }
X
X /* Unsuccessful return -- one of the tests failed */
X if (unlink(ofname))
X perror(ofname);
X}
X/*
X * This routine returns 1 if we are running in the foreground and stderr
X * is a tty.
X */
Xint foreground()
X{
X#ifndef METAWARE
X if(bgnd_flag) { /* background? */
X return(0);
X } else { /* foreground */
X#endif
X if(isatty(2)) { /* and stderr is a tty */
X return(1);
X } else {
X return(0);
X }
X#ifndef METAWARE
X }
X#endif
X}
X#ifndef METAWARE
Xvoid onintr ( )
X{
X (void)signal(SIGINT,SIG_IGN);
X unlink ( ofname );
X exit ( 1 );
X}
X
Xvoid oops ( ) /* wild pointer -- assume bad input */
X{
X (void)signal(SIGSEGV,SIG_IGN);
X if ( do_decomp == 1 )
X fprintf ( stderr, "uncompress: corrupt input\n" );
X unlink ( ofname );
X exit ( 1 );
X}
X#endif
Xvoid cl_block () /* table clear for block compress */
X{
X REGISTER long int rat;
X
X checkpoint = in_count + CHECK_GAP;
X#ifdef DEBUG
X if ( debug ) {
X fprintf ( stderr, "count: %ld, ratio: ", in_count );
X prratio ( stderr, in_count, bytes_out );
X fprintf ( stderr, "\n");
X }
X#endif /* DEBUG */
X
X if(in_count > 0x007fffff) { /* shift will overflow */
X rat = bytes_out >> 8;
X if(rat == 0) { /* Don't divide by zero */
X rat = 0x7fffffff;
X } else {
X rat = in_count / rat;
X }
X } else {
X rat = (in_count << 8) / bytes_out; /* 8 fractional bits */
X }
X if ( rat > ratio ) {
X ratio = rat;
X } else {
X ratio = 0;
X#ifdef DEBUG
X if(verbose)
X dump_tab(); /* dump string table */
X#endif
X cl_hash ( (count_int) hsize );
X free_ent = FIRST;
X clear_flg = 1;
X output ( (code_int) CLEAR );
X#ifdef DEBUG
X if(debug)
X fprintf ( stderr, "clear\n" );
X#endif /* DEBUG */
X }
X}
X
Xvoid cl_hash(hsize) /* reset code table */
X REGISTER count_int hsize;
X{
X#ifdef AZTEC86
X#ifdef PCDOS
X /* this function only in PC-DOS lib, not in MINIX lib */
X memset(htab,-1,(int)(hsize * sizeof(count_int)));
X#else
X/* MINIX and all non-PC machines do it this way */
X#ifndef XENIX_16 /* Normal machine */
X REGISTER count_int *htab_p = htab+hsize;
X#else
X REGISTER j;
X REGISTER long k = hsize;
X REGISTER count_int *htab_p;
X#endif
X REGISTER long i;
X REGISTER long m1 = -1;
X
X#ifdef XENIX_16
X for(j=0; j<=8 && k>=0; j++,k-=8192)
X {
X i = 8192;
X if(k < 8192)
X {
X i = k;
X }
X htab_p = &(htab[j][i]);
X i -= 16;
X if(i > 0)
X {
X#else
X i = hsize - 16;
X#endif
X do
X { /* might use Sys V memset(3) here */
X *(htab_p-16) = m1;
X *(htab_p-15) = m1;
X *(htab_p-14) = m1;
X *(htab_p-13) = m1;
X *(htab_p-12) = m1;
X *(htab_p-11) = m1;
X *(htab_p-10) = m1;
X *(htab_p-9) = m1;
X *(htab_p-8) = m1;
X *(htab_p-7) = m1;
X *(htab_p-6) = m1;
X *(htab_p-5) = m1;
X *(htab_p-4) = m1;
X *(htab_p-3) = m1;
X *(htab_p-2) = m1;
X *(htab_p-1) = m1;
X htab_p -= 16;
X } while ((i -= 16) >= 0);
X#ifdef XENIX_16
X }
X }
X#endif
X for ( i += 16; i > 0; i-- )
X *--htab_p = m1;
X#endif
X#endif
X}
X
Xvoid prratio(stream, num, den)
XFILE *stream;
Xlong int num, den;
X{
X REGISTER int q; /* Doesn't need to be long */
X if(num > 214748L)
X { /* 2147483647/10000 */
X q = (int)(num / (den / 10000L));
X } else
X {
X q = (int)(10000L * num / den); /* Long calculations, though */
X }
X if (q < 0)
X {
X putc('-', stream);
X q = -q;
X }
X fprintf(stream, "%d.%02d%%", q / 100, q % 100);
X}
X
Xvoid version()
X{
X fprintf(stderr, "%s\n", rcs_ident);
X fprintf(stderr, "Options: ");
X#ifdef vax
X fprintf(stderr, "vax, ");
X#endif
X#ifdef MINIX
X fprintf(stderr, "MINIX, ");
X#endif
X#ifdef NO_UCHAR
X fprintf(stderr, "NO_UCHAR, ");
X#endif
X#ifdef SIGNED_COMPARE_SLOW
X fprintf(stderr, "SIGNED_COMPARE_SLOW, ");
X#endif
X#ifdef XENIX_16
X fprintf(stderr, "XENIX_16, ");
X#endif
X#ifdef COMPATIBLE
X fprintf(stderr, "COMPATIBLE, ");
X#endif
X#ifdef DEBUG
X fprintf(stderr, "DEBUG, ");
X#endif
X#ifdef BSD4_2
X fprintf(stderr, "BSD4_2, ");
X#endif
X fprintf(stderr, "BITS = %d\n", BITS);
X}
X/* End of text from uok.UUCP:net.sources */
X
EOF