1309 lines
33 KiB
Plaintext
1309 lines
33 KiB
Plaintext
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/*
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* Copyright (c) 1985, 1986 The Regents of the University of California.
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* All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* James A. Woods, derived from original work by Spencer Thomas
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* and Joseph Orost.
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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 the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#ifndef lint
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char copyright[] =
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"@(#) Copyright (c) 1985, 1986 The Regents of the University of California.\n\
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All rights reserved.\n";
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#endif /* not lint */
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#ifndef lint
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static char sccsid[] = "@(#)compress.c 5.19 (Berkeley) 3/18/91";
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#endif /* not lint */
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/*
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* compress.c - File compression ala IEEE Computer, June 1984.
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*
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* Authors: Spencer W. Thomas (decvax!utah-cs!thomas)
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* Jim McKie (decvax!mcvax!jim)
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* Steve Davies (decvax!vax135!petsd!peora!srd)
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* Ken Turkowski (decvax!decwrl!turtlevax!ken)
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* James A. Woods (decvax!ihnp4!ames!jaw)
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* Joe Orost (decvax!vax135!petsd!joe)
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*/
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#include <sys/param.h>
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#include <sys/stat.h>
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#include <signal.h>
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#include <utime.h>
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#include <errno.h>
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#include <unistd.h>
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#include <stdio.h>
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#include <ctype.h>
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#include <stdlib.h>
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#include <string.h>
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/*
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* Set USERMEM to the maximum amount of physical user memory available
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* in bytes. USERMEM is used to determine the maximum BITS that can be used
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* for compression.
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*
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* SACREDMEM is the amount of physical memory saved for others; compress
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* will hog the rest.
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*/
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#ifndef SACREDMEM
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#define SACREDMEM 0
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#endif
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#ifndef USERMEM
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# define USERMEM 450000 /* default user memory */
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#endif
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#ifdef pdp11
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# define BITS 12 /* max bits/code for 16-bit machine */
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# define NO_UCHAR /* also if "unsigned char" functions as signed char */
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# undef USERMEM
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#endif /* pdp11 */ /* don't forget to compile with -i */
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#ifdef USERMEM
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# if USERMEM >= (433484+SACREDMEM)
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# define PBITS 16
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# else
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# if USERMEM >= (229600+SACREDMEM)
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# define PBITS 15
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# else
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# if USERMEM >= (127536+SACREDMEM)
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# define PBITS 14
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# else
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# if USERMEM >= (73464+SACREDMEM)
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# define PBITS 13
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# else
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# define PBITS 12
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# endif
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# endif
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# endif
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# endif
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# undef USERMEM
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#endif /* USERMEM */
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#ifdef PBITS /* Preferred BITS for this memory size */
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# ifndef BITS
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# define BITS PBITS
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# endif BITS
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#endif /* PBITS */
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#if BITS == 16
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# define HSIZE 69001 /* 95% occupancy */
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#endif
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#if BITS == 15
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# define HSIZE 35023 /* 94% occupancy */
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#endif
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#if BITS == 14
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# define HSIZE 18013 /* 91% occupancy */
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#endif
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#if BITS == 13
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# define HSIZE 9001 /* 91% occupancy */
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#endif
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#if BITS <= 12
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# define HSIZE 5003 /* 80% occupancy */
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#endif
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/*
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* a code_int must be able to hold 2**BITS values of type int, and also -1
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*/
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#if BITS > 15
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typedef long int code_int;
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#else
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typedef int code_int;
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#endif
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#ifdef SIGNED_COMPARE_SLOW
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typedef unsigned long int count_int;
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typedef unsigned short int count_short;
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#else
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typedef long int count_int;
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#endif
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#ifdef NO_UCHAR
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typedef char char_type;
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#else
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typedef unsigned char char_type;
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#endif /* UCHAR */
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char_type magic_header[] = { "\037\235" }; /* 1F 9D */
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/* Defines for third byte of header */
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#define BIT_MASK 0x1f
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#define BLOCK_MASK 0x80
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/* Masks 0x40 and 0x20 are free. I think 0x20 should mean that there is
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a fourth header byte (for expansion).
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*/
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#define INIT_BITS 9 /* initial number of bits/code */
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int n_bits; /* number of bits/code */
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int maxbits = BITS; /* user settable max # bits/code */
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code_int maxcode; /* maximum code, given n_bits */
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code_int maxmaxcode = 1 << BITS; /* should NEVER generate this code */
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#ifdef COMPATIBLE /* But wrong! */
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# define MAXCODE(n_bits) (1 << (n_bits) - 1)
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#else
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# define MAXCODE(n_bits) ((1 << (n_bits)) - 1)
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#endif /* COMPATIBLE */
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count_int htab [HSIZE];
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unsigned short codetab [HSIZE];
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#define htabof(i) htab[i]
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#define codetabof(i) codetab[i]
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code_int hsize = HSIZE; /* for dynamic table sizing */
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count_int fsize;
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/*
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* To save much memory, we overlay the table used by compress() with those
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* used by decompress(). The tab_prefix table is the same size and type
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* as the codetab. The tab_suffix table needs 2**BITS characters. We
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* get this from the beginning of htab. The output stack uses the rest
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* of htab, and contains characters. There is plenty of room for any
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* possible stack (stack used to be 8000 characters).
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*/
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#define tab_prefixof(i) codetabof(i)
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# define tab_suffixof(i) ((char_type *)(htab))[i]
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# define de_stack ((char_type *)&tab_suffixof(1<<BITS))
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code_int free_ent = 0; /* first unused entry */
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int exit_stat = 0; /* per-file status */
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int perm_stat = 0; /* permanent status */
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code_int getcode();
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int nomagic = 0; /* Use a 3-byte magic number header, unless old file */
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int zcat_flg = 0; /* Write output on stdout, suppress messages */
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int precious = 1; /* Don't unlink output file on interrupt */
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int quiet = 1; /* don't tell me about compression */
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/*
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* block compression parameters -- after all codes are used up,
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* and compression rate changes, start over.
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*/
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int block_compress = BLOCK_MASK;
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int clear_flg = 0;
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long int ratio = 0;
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#define CHECK_GAP 10000 /* ratio check interval */
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count_int checkpoint = CHECK_GAP;
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/*
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* the next two codes should not be changed lightly, as they must not
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* lie within the contiguous general code space.
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*/
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#define FIRST 257 /* first free entry */
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#define CLEAR 256 /* table clear output code */
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int force = 0;
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char ofname [100];
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#ifdef DEBUG
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int debug, verbose;
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#endif
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sig_t oldint;
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int bgnd_flag;
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int do_decomp = 0;
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/*-
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* Algorithm from "A Technique for High Performance Data Compression",
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* Terry A. Welch, IEEE Computer Vol 17, No 6 (June 1984), pp 8-19.
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*
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* Usage: compress [-dfvc] [-b bits] [file ...]
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* Inputs:
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* -d: If given, decompression is done instead.
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*
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* -c: Write output on stdout, don't remove original.
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*
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* -b: Parameter limits the max number of bits/code.
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*
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* -f: Forces output file to be generated, even if one already
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* exists, and even if no space is saved by compressing.
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* If -f is not used, the user will be prompted if stdin is
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* a tty, otherwise, the output file will not be overwritten.
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*
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* -v: Write compression statistics
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*
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* file ...: Files to be compressed. If none specified, stdin
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* is used.
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* Outputs:
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* file.Z: Compressed form of file with same mode, owner, and utimes
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* or stdout (if stdin used as input)
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*
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* Assumptions:
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* When filenames are given, replaces with the compressed version
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* (.Z suffix) only if the file decreases in size.
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* Algorithm:
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* Modified Lempel-Ziv method (LZW). Basically finds common
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* substrings and replaces them with a variable size code. This is
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* deterministic, and can be done on the fly. Thus, the decompression
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* procedure needs no input table, but tracks the way the table was built.
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*/
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main(argc, argv)
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int argc;
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char **argv;
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{
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extern int optind;
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extern char *optarg;
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struct stat statbuf;
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int ch, overwrite;
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char **filelist, **fileptr, *cp, tempname[MAXPATHLEN];
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void onintr(), oops();
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/* This bg check only works for sh. */
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if ((oldint = signal(SIGINT, SIG_IGN)) != SIG_IGN) {
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(void)signal(SIGINT, onintr);
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(void)signal(SIGSEGV, oops); /* XXX */
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}
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bgnd_flag = oldint != SIG_DFL;
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#ifdef COMPATIBLE
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nomagic = 1; /* Original didn't have a magic number */
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#endif
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if (cp = rindex(argv[0], '/'))
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++cp;
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else
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cp = argv[0];
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if (strcmp(cp, "uncompress") == 0)
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do_decomp = 1;
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else if(strcmp(cp, "zcat") == 0) {
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do_decomp = 1;
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zcat_flg = 1;
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}
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/*
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* -b maxbits => maxbits.
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* -C => generate output compatible with compress 2.0.
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* -c => cat all output to stdout
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* -D => debug
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* -d => do_decomp
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* -f => force overwrite of output file
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* -n => no header: useful to uncompress old files
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* -V => print Version; debug verbose
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* -v => unquiet
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*/
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overwrite = 0;
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#ifdef DEBUG
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while ((ch = getopt(argc, argv, "b:CcDdfnVv")) != EOF)
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#else
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while ((ch = getopt(argc, argv, "b:Ccdfnv")) != EOF)
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#endif
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switch(ch) {
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case 'b':
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maxbits = atoi(optarg);
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break;
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case 'C':
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block_compress = 0;
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break;
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case 'c':
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zcat_flg = 1;
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break;
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#ifdef DEBUG
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case 'D':
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debug = 1;
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break;
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#endif
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case 'd':
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do_decomp = 1;
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break;
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case 'f':
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overwrite = 1;
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force = 1;
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break;
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case 'n':
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nomagic = 1;
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break;
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case 'q':
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quiet = 1;
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break;
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#ifdef DEBUG
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case 'V':
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verbose = 1;
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break;
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#endif
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case 'v':
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quiet = 0;
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break;
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case '?':
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default:
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usage();
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}
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argc -= optind;
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argv += optind;
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if (maxbits < INIT_BITS)
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maxbits = INIT_BITS;
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if (maxbits > BITS)
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maxbits = BITS;
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maxmaxcode = 1 << maxbits;
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/* Build useless input file list. */
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filelist = fileptr = (char **)(malloc(argc * sizeof(*argv)));
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while (*argv)
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*fileptr++ = *argv++;
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*fileptr = NULL;
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if (*filelist != NULL) {
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for (fileptr = filelist; *fileptr; fileptr++) {
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exit_stat = 0;
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if (do_decomp) { /* DECOMPRESSION */
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/* Check for .Z suffix */
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if (strcmp(*fileptr + strlen(*fileptr) - 2, ".Z") != 0) {
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/* No .Z: tack one on */
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strcpy(tempname, *fileptr);
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strcat(tempname, ".Z");
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*fileptr = tempname;
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}
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/* Open input file */
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if ((freopen(*fileptr, "r", stdin)) == NULL) {
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perror(*fileptr);
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perm_stat = 1;
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continue;
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}
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/* Check the magic number */
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if (nomagic == 0) {
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if ((getchar() != (magic_header[0] & 0xFF))
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|| (getchar() != (magic_header[1] & 0xFF))) {
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fprintf(stderr, "%s: not in compressed format\n",
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*fileptr);
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continue;
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}
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maxbits = getchar(); /* set -b from file */
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block_compress = maxbits & BLOCK_MASK;
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maxbits &= BIT_MASK;
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maxmaxcode = 1 << maxbits;
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if(maxbits > BITS) {
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fprintf(stderr,
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"%s: compressed with %d bits, can only handle %d bits\n",
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*fileptr, maxbits, BITS);
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continue;
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}
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}
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/* Generate output filename */
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strcpy(ofname, *fileptr);
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ofname[strlen(*fileptr) - 2] = '\0'; /* Strip off .Z */
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} else { /* COMPRESSION */
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if (strcmp(*fileptr + strlen(*fileptr) - 2, ".Z") == 0) {
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fprintf(stderr, "%s: already has .Z suffix -- no change\n",
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*fileptr);
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continue;
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}
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/* Open input file */
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if ((freopen(*fileptr, "r", stdin)) == NULL) {
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perror(*fileptr);
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perm_stat = 1;
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continue;
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}
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stat ( *fileptr, &statbuf );
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fsize = (long) statbuf.st_size;
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/*
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* tune hash table size for small files -- ad hoc,
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* but the sizes match earlier #defines, which
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* serve as upper bounds on the number of output codes.
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*/
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hsize = HSIZE;
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if ( fsize < (1 << 12) )
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hsize = MIN ( 5003, HSIZE );
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else if ( fsize < (1 << 13) )
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hsize = MIN ( 9001, HSIZE );
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else if ( fsize < (1 << 14) )
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||
|
hsize = MIN ( 18013, HSIZE );
|
||
|
else if ( fsize < (1 << 15) )
|
||
|
hsize = MIN ( 35023, HSIZE );
|
||
|
else if ( fsize < 47000 )
|
||
|
hsize = MIN ( 50021, HSIZE );
|
||
|
|
||
|
/* Generate output filename */
|
||
|
strcpy(ofname, *fileptr);
|
||
|
strcat(ofname, ".Z");
|
||
|
}
|
||
|
/* Check for overwrite of existing file */
|
||
|
if (overwrite == 0 && zcat_flg == 0) {
|
||
|
if (stat(ofname, &statbuf) == 0) {
|
||
|
char response[2];
|
||
|
response[0] = 'n';
|
||
|
fprintf(stderr, "%s already exists;", ofname);
|
||
|
if (bgnd_flag == 0 && isatty(2)) {
|
||
|
fprintf(stderr, " do you wish to overwrite %s (y or n)? ",
|
||
|
ofname);
|
||
|
fflush(stderr);
|
||
|
read(2, response, 2);
|
||
|
while (response[1] != '\n') {
|
||
|
if (read(2, response+1, 1) < 0) { /* Ack! */
|
||
|
perror("stderr"); break;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
if (response[0] != 'y') {
|
||
|
fprintf(stderr, "\tnot overwritten\n");
|
||
|
continue;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
if(zcat_flg == 0) { /* Open output file */
|
||
|
if (freopen(ofname, "w", stdout) == NULL) {
|
||
|
perror(ofname);
|
||
|
perm_stat = 1;
|
||
|
continue;
|
||
|
}
|
||
|
precious = 0;
|
||
|
if(!quiet)
|
||
|
fprintf(stderr, "%s: ", *fileptr);
|
||
|
}
|
||
|
|
||
|
/* Actually do the compression/decompression */
|
||
|
if (do_decomp == 0) compress();
|
||
|
#ifndef DEBUG
|
||
|
else decompress();
|
||
|
#else
|
||
|
else if (debug == 0) decompress();
|
||
|
else printcodes();
|
||
|
if (verbose) dump_tab();
|
||
|
#endif /* DEBUG */
|
||
|
if(zcat_flg == 0) {
|
||
|
copystat(*fileptr, ofname); /* Copy stats */
|
||
|
precious = 1;
|
||
|
if((exit_stat == 1) || (!quiet))
|
||
|
putc('\n', stderr);
|
||
|
}
|
||
|
}
|
||
|
} else { /* Standard input */
|
||
|
if (do_decomp == 0) {
|
||
|
compress();
|
||
|
#ifdef DEBUG
|
||
|
if(verbose) dump_tab();
|
||
|
#endif /* DEBUG */
|
||
|
if(!quiet)
|
||
|
putc('\n', stderr);
|
||
|
} else {
|
||
|
/* Check the magic number */
|
||
|
if (nomagic == 0) {
|
||
|
if ((getchar()!=(magic_header[0] & 0xFF))
|
||
|
|| (getchar()!=(magic_header[1] & 0xFF))) {
|
||
|
fprintf(stderr, "stdin: not in compressed format\n");
|
||
|
exit(1);
|
||
|
}
|
||
|
maxbits = getchar(); /* set -b from file */
|
||
|
block_compress = maxbits & BLOCK_MASK;
|
||
|
maxbits &= BIT_MASK;
|
||
|
maxmaxcode = 1 << maxbits;
|
||
|
fsize = 100000; /* assume stdin large for USERMEM */
|
||
|
if(maxbits > BITS) {
|
||
|
fprintf(stderr,
|
||
|
"stdin: compressed with %d bits, can only handle %d bits\n",
|
||
|
maxbits, BITS);
|
||
|
exit(1);
|
||
|
}
|
||
|
}
|
||
|
#ifndef DEBUG
|
||
|
decompress();
|
||
|
#else
|
||
|
if (debug == 0) decompress();
|
||
|
else printcodes();
|
||
|
if (verbose) dump_tab();
|
||
|
#endif /* DEBUG */
|
||
|
}
|
||
|
}
|
||
|
exit(perm_stat ? perm_stat : exit_stat);
|
||
|
}
|
||
|
|
||
|
static int offset;
|
||
|
long int in_count = 1; /* length of input */
|
||
|
long int bytes_out; /* length of compressed output */
|
||
|
long int out_count = 0; /* # of codes output (for debugging) */
|
||
|
|
||
|
/*
|
||
|
* compress stdin to stdout
|
||
|
*
|
||
|
* Algorithm: use open addressing double hashing (no chaining) on the
|
||
|
* prefix code / next character combination. We do a variant of Knuth's
|
||
|
* algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime
|
||
|
* secondary probe. Here, the modular division first probe is gives way
|
||
|
* to a faster exclusive-or manipulation. Also do block compression with
|
||
|
* an adaptive reset, whereby the code table is cleared when the compression
|
||
|
* ratio decreases, but after the table fills. The variable-length output
|
||
|
* codes are re-sized at this point, and a special CLEAR code is generated
|
||
|
* for the decompressor. Late addition: construct the table according to
|
||
|
* file size for noticeable speed improvement on small files. Please direct
|
||
|
* questions about this implementation to ames!jaw.
|
||
|
*/
|
||
|
|
||
|
compress()
|
||
|
{
|
||
|
register long fcode;
|
||
|
register code_int i = 0;
|
||
|
register int c;
|
||
|
register code_int ent;
|
||
|
register int disp;
|
||
|
register code_int hsize_reg;
|
||
|
register int hshift;
|
||
|
|
||
|
#ifndef COMPATIBLE
|
||
|
if (nomagic == 0) {
|
||
|
putchar(magic_header[0]);
|
||
|
putchar(magic_header[1]);
|
||
|
putchar((char)(maxbits | block_compress));
|
||
|
if(ferror(stdout))
|
||
|
writeerr();
|
||
|
}
|
||
|
#endif /* COMPATIBLE */
|
||
|
|
||
|
offset = 0;
|
||
|
bytes_out = 3; /* includes 3-byte header mojo */
|
||
|
out_count = 0;
|
||
|
clear_flg = 0;
|
||
|
ratio = 0;
|
||
|
in_count = 1;
|
||
|
checkpoint = CHECK_GAP;
|
||
|
maxcode = MAXCODE(n_bits = INIT_BITS);
|
||
|
free_ent = ((block_compress) ? FIRST : 256 );
|
||
|
|
||
|
ent = getchar ();
|
||
|
|
||
|
hshift = 0;
|
||
|
for ( fcode = (long) hsize; fcode < 65536L; fcode *= 2L )
|
||
|
hshift++;
|
||
|
hshift = 8 - hshift; /* set hash code range bound */
|
||
|
|
||
|
hsize_reg = hsize;
|
||
|
cl_hash( (count_int) hsize_reg); /* clear hash table */
|
||
|
|
||
|
#ifdef SIGNED_COMPARE_SLOW
|
||
|
while ( (c = getchar()) != (unsigned) EOF ) {
|
||
|
#else
|
||
|
while ( (c = getchar()) != EOF ) {
|
||
|
#endif
|
||
|
in_count++;
|
||
|
fcode = (long) (((long) c << maxbits) + ent);
|
||
|
i = ((c << hshift) ^ ent); /* xor hashing */
|
||
|
|
||
|
if ( htabof (i) == fcode ) {
|
||
|
ent = codetabof (i);
|
||
|
continue;
|
||
|
} else if ( (long)htabof (i) < 0 ) /* empty slot */
|
||
|
goto nomatch;
|
||
|
disp = hsize_reg - i; /* secondary hash (after G. Knott) */
|
||
|
if ( i == 0 )
|
||
|
disp = 1;
|
||
|
probe:
|
||
|
if ( (i -= disp) < 0 )
|
||
|
i += hsize_reg;
|
||
|
|
||
|
if ( htabof (i) == fcode ) {
|
||
|
ent = codetabof (i);
|
||
|
continue;
|
||
|
}
|
||
|
if ( (long)htabof (i) > 0 )
|
||
|
goto probe;
|
||
|
nomatch:
|
||
|
output ( (code_int) ent );
|
||
|
out_count++;
|
||
|
ent = c;
|
||
|
#ifdef SIGNED_COMPARE_SLOW
|
||
|
if ( (unsigned) free_ent < (unsigned) maxmaxcode) {
|
||
|
#else
|
||
|
if ( free_ent < maxmaxcode ) {
|
||
|
#endif
|
||
|
codetabof (i) = free_ent++; /* code -> hashtable */
|
||
|
htabof (i) = fcode;
|
||
|
}
|
||
|
else if ( (count_int)in_count >= checkpoint && block_compress )
|
||
|
cl_block ();
|
||
|
}
|
||
|
/*
|
||
|
* Put out the final code.
|
||
|
*/
|
||
|
output( (code_int)ent );
|
||
|
out_count++;
|
||
|
output( (code_int)-1 );
|
||
|
|
||
|
/*
|
||
|
* Print out stats on stderr
|
||
|
*/
|
||
|
if(zcat_flg == 0 && !quiet) {
|
||
|
#ifdef DEBUG
|
||
|
fprintf( stderr,
|
||
|
"%ld chars in, %ld codes (%ld bytes) out, compression factor: ",
|
||
|
in_count, out_count, bytes_out );
|
||
|
prratio( stderr, in_count, bytes_out );
|
||
|
fprintf( stderr, "\n");
|
||
|
fprintf( stderr, "\tCompression as in compact: " );
|
||
|
prratio( stderr, in_count-bytes_out, in_count );
|
||
|
fprintf( stderr, "\n");
|
||
|
fprintf( stderr, "\tLargest code (of last block) was %d (%d bits)\n",
|
||
|
free_ent - 1, n_bits );
|
||
|
#else /* !DEBUG */
|
||
|
fprintf( stderr, "Compression: " );
|
||
|
prratio( stderr, in_count-bytes_out, in_count );
|
||
|
#endif /* DEBUG */
|
||
|
}
|
||
|
if(bytes_out > in_count) /* exit(2) if no savings */
|
||
|
exit_stat = 2;
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
/*-
|
||
|
* Output the given code.
|
||
|
* Inputs:
|
||
|
* code: A n_bits-bit integer. If == -1, then EOF. This assumes
|
||
|
* that n_bits =< (long)wordsize - 1.
|
||
|
* Outputs:
|
||
|
* Outputs code to the file.
|
||
|
* Assumptions:
|
||
|
* Chars are 8 bits long.
|
||
|
* Algorithm:
|
||
|
* Maintain a BITS character long buffer (so that 8 codes will
|
||
|
* fit in it exactly). Use the VAX insv instruction to insert each
|
||
|
* code in turn. When the buffer fills up empty it and start over.
|
||
|
*/
|
||
|
|
||
|
static char buf[BITS];
|
||
|
|
||
|
#ifndef vax
|
||
|
char_type lmask[9] = {0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80, 0x00};
|
||
|
char_type rmask[9] = {0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff};
|
||
|
#endif /* vax */
|
||
|
|
||
|
output( code )
|
||
|
code_int code;
|
||
|
{
|
||
|
#ifdef DEBUG
|
||
|
static int col = 0;
|
||
|
#endif /* DEBUG */
|
||
|
|
||
|
/*
|
||
|
* On the VAX, it is important to have the register declarations
|
||
|
* in exactly the order given, or the asm will break.
|
||
|
*/
|
||
|
register int r_off = offset, bits= n_bits;
|
||
|
register char * bp = buf;
|
||
|
|
||
|
#ifdef DEBUG
|
||
|
if ( verbose )
|
||
|
fprintf( stderr, "%5d%c", code,
|
||
|
(col+=6) >= 74 ? (col = 0, '\n') : ' ' );
|
||
|
#endif /* DEBUG */
|
||
|
if ( code >= 0 ) {
|
||
|
#if defined(vax) && !defined(__GNUC__)
|
||
|
/*
|
||
|
* VAX and PCC DEPENDENT!! Implementation on other machines is
|
||
|
* below.
|
||
|
*
|
||
|
* Translation: Insert BITS bits from the argument starting at
|
||
|
* offset bits from the beginning of buf.
|
||
|
*/
|
||
|
0; /* Work around for pcc -O bug with asm and if stmt */
|
||
|
asm( "insv 4(ap),r11,r10,(r9)" );
|
||
|
#else
|
||
|
/*
|
||
|
* byte/bit numbering on the VAX is simulated by the following code
|
||
|
*/
|
||
|
/*
|
||
|
* Get to the first byte.
|
||
|
*/
|
||
|
bp += (r_off >> 3);
|
||
|
r_off &= 7;
|
||
|
/*
|
||
|
* Since code is always >= 8 bits, only need to mask the first
|
||
|
* hunk on the left.
|
||
|
*/
|
||
|
*bp = (*bp & rmask[r_off]) | (code << r_off) & lmask[r_off];
|
||
|
bp++;
|
||
|
bits -= (8 - r_off);
|
||
|
code >>= 8 - r_off;
|
||
|
/* Get any 8 bit parts in the middle (<=1 for up to 16 bits). */
|
||
|
if ( bits >= 8 ) {
|
||
|
*bp++ = code;
|
||
|
code >>= 8;
|
||
|
bits -= 8;
|
||
|
}
|
||
|
/* Last bits. */
|
||
|
if(bits)
|
||
|
*bp = code;
|
||
|
#endif /* vax */
|
||
|
offset += n_bits;
|
||
|
if ( offset == (n_bits << 3) ) {
|
||
|
bp = buf;
|
||
|
bits = n_bits;
|
||
|
bytes_out += bits;
|
||
|
do {
|
||
|
putchar(*bp++);
|
||
|
if (ferror(stdout))
|
||
|
writeerr();
|
||
|
} while(--bits);
|
||
|
offset = 0;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* If the next entry is going to be too big for the code size,
|
||
|
* then increase it, if possible.
|
||
|
*/
|
||
|
if ( free_ent > maxcode || (clear_flg > 0))
|
||
|
{
|
||
|
/*
|
||
|
* Write the whole buffer, because the input side won't
|
||
|
* discover the size increase until after it has read it.
|
||
|
*/
|
||
|
if ( offset > 0 ) {
|
||
|
if( fwrite( buf, 1, n_bits, stdout ) != n_bits)
|
||
|
writeerr();
|
||
|
bytes_out += n_bits;
|
||
|
}
|
||
|
offset = 0;
|
||
|
|
||
|
if ( clear_flg ) {
|
||
|
maxcode = MAXCODE (n_bits = INIT_BITS);
|
||
|
clear_flg = 0;
|
||
|
}
|
||
|
else {
|
||
|
n_bits++;
|
||
|
if ( n_bits == maxbits )
|
||
|
maxcode = maxmaxcode;
|
||
|
else
|
||
|
maxcode = MAXCODE(n_bits);
|
||
|
}
|
||
|
#ifdef DEBUG
|
||
|
if ( debug ) {
|
||
|
fprintf( stderr, "\nChange to %d bits\n", n_bits );
|
||
|
col = 0;
|
||
|
}
|
||
|
#endif /* DEBUG */
|
||
|
}
|
||
|
} else {
|
||
|
/*
|
||
|
* At EOF, write the rest of the buffer.
|
||
|
*/
|
||
|
if ( offset > 0 ) {
|
||
|
offset = (offset + 7) / 8;
|
||
|
if( fwrite( buf, 1, offset, stdout ) != offset )
|
||
|
writeerr();
|
||
|
bytes_out += offset;
|
||
|
}
|
||
|
offset = 0;
|
||
|
(void)fflush( stdout );
|
||
|
if( ferror( stdout ) )
|
||
|
writeerr();
|
||
|
#ifdef DEBUG
|
||
|
if ( verbose )
|
||
|
fprintf( stderr, "\n" );
|
||
|
#endif
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Decompress stdin to stdout. This routine adapts to the codes in the
|
||
|
* file building the "string" table on-the-fly; requiring no table to
|
||
|
* be stored in the compressed file. The tables used herein are shared
|
||
|
* with those of the compress() routine. See the definitions above.
|
||
|
*/
|
||
|
|
||
|
decompress() {
|
||
|
register char_type *stackp;
|
||
|
register int finchar;
|
||
|
register code_int code, oldcode, incode;
|
||
|
int n, nwritten, offset; /* Variables for buffered write */
|
||
|
char buff[BUFSIZ]; /* Buffer for buffered write */
|
||
|
|
||
|
|
||
|
/*
|
||
|
* As above, initialize the first 256 entries in the table.
|
||
|
*/
|
||
|
maxcode = MAXCODE(n_bits = INIT_BITS);
|
||
|
for ( code = 255; code >= 0; code-- ) {
|
||
|
tab_prefixof(code) = 0;
|
||
|
tab_suffixof(code) = (char_type)code;
|
||
|
}
|
||
|
free_ent = ((block_compress) ? FIRST : 256 );
|
||
|
|
||
|
finchar = oldcode = getcode();
|
||
|
if(oldcode == -1) /* EOF already? */
|
||
|
return; /* Get out of here */
|
||
|
|
||
|
/* first code must be 8 bits = char */
|
||
|
n=0;
|
||
|
buff[n++] = (char)finchar;
|
||
|
|
||
|
stackp = de_stack;
|
||
|
|
||
|
while ( (code = getcode()) > -1 ) {
|
||
|
|
||
|
if ( (code == CLEAR) && block_compress ) {
|
||
|
for ( code = 255; code >= 0; code-- )
|
||
|
tab_prefixof(code) = 0;
|
||
|
clear_flg = 1;
|
||
|
free_ent = FIRST - 1;
|
||
|
if ( (code = getcode ()) == -1 ) /* O, untimely death! */
|
||
|
break;
|
||
|
}
|
||
|
incode = code;
|
||
|
/*
|
||
|
* Special case for KwKwK string.
|
||
|
*/
|
||
|
if ( code >= free_ent ) {
|
||
|
*stackp++ = finchar;
|
||
|
code = oldcode;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Generate output characters in reverse order
|
||
|
*/
|
||
|
#ifdef SIGNED_COMPARE_SLOW
|
||
|
while ( ((unsigned long)code) >= ((unsigned long)256) ) {
|
||
|
#else
|
||
|
while ( code >= 256 ) {
|
||
|
#endif
|
||
|
*stackp++ = tab_suffixof(code);
|
||
|
code = tab_prefixof(code);
|
||
|
}
|
||
|
*stackp++ = finchar = tab_suffixof(code);
|
||
|
|
||
|
/*
|
||
|
* And put them out in forward order
|
||
|
*/
|
||
|
do {
|
||
|
/*
|
||
|
* About 60% of the time is spent in the putchar() call
|
||
|
* that appeared here. It was originally
|
||
|
* putchar ( *--stackp );
|
||
|
* If we buffer the writes ourselves, we can go faster (about
|
||
|
* 30%).
|
||
|
*
|
||
|
* At this point, the next line is the next *big* time
|
||
|
* sink in the code. It takes up about 10% of the time.
|
||
|
*/
|
||
|
buff[n++] = *--stackp;
|
||
|
if (n == BUFSIZ) {
|
||
|
offset = 0;
|
||
|
do {
|
||
|
nwritten = write(fileno(stdout), &buff[offset], n);
|
||
|
if (nwritten < 0)
|
||
|
writeerr();
|
||
|
offset += nwritten;
|
||
|
} while ((n -= nwritten) > 0);
|
||
|
}
|
||
|
} while ( stackp > de_stack );
|
||
|
|
||
|
/*
|
||
|
* Generate the new entry.
|
||
|
*/
|
||
|
if ( (code=free_ent) < maxmaxcode ) {
|
||
|
tab_prefixof(code) = (unsigned short)oldcode;
|
||
|
tab_suffixof(code) = finchar;
|
||
|
free_ent = code+1;
|
||
|
}
|
||
|
/*
|
||
|
* Remember previous code.
|
||
|
*/
|
||
|
oldcode = incode;
|
||
|
}
|
||
|
/*
|
||
|
* Flush the stuff remaining in our buffer...
|
||
|
*/
|
||
|
offset = 0;
|
||
|
while (n > 0) {
|
||
|
nwritten = write(fileno(stdout), &buff[offset], n);
|
||
|
if (nwritten < 0)
|
||
|
writeerr();
|
||
|
offset += nwritten;
|
||
|
n -= nwritten;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/*-
|
||
|
* Read one code from the standard input. If EOF, return -1.
|
||
|
* Inputs:
|
||
|
* stdin
|
||
|
* Outputs:
|
||
|
* code or -1 is returned.
|
||
|
*/
|
||
|
code_int
|
||
|
getcode() {
|
||
|
/*
|
||
|
* On the VAX, it is important to have the register declarations
|
||
|
* in exactly the order given, or the asm will break.
|
||
|
*/
|
||
|
register code_int code;
|
||
|
static int offset = 0, size = 0;
|
||
|
static char_type buf[BITS];
|
||
|
register int r_off, bits;
|
||
|
register char_type *bp = buf;
|
||
|
|
||
|
if ( clear_flg > 0 || offset >= size || free_ent > maxcode ) {
|
||
|
/*
|
||
|
* If the next entry will be too big for the current code
|
||
|
* size, then we must increase the size. This implies reading
|
||
|
* a new buffer full, too.
|
||
|
*/
|
||
|
if ( free_ent > maxcode ) {
|
||
|
n_bits++;
|
||
|
if ( n_bits == maxbits )
|
||
|
maxcode = maxmaxcode; /* won't get any bigger now */
|
||
|
else
|
||
|
maxcode = MAXCODE(n_bits);
|
||
|
}
|
||
|
if ( clear_flg > 0) {
|
||
|
maxcode = MAXCODE (n_bits = INIT_BITS);
|
||
|
clear_flg = 0;
|
||
|
}
|
||
|
size = fread( buf, 1, n_bits, stdin );
|
||
|
if ( size <= 0 )
|
||
|
return -1; /* end of file */
|
||
|
offset = 0;
|
||
|
/* Round size down to integral number of codes */
|
||
|
size = (size << 3) - (n_bits - 1);
|
||
|
}
|
||
|
r_off = offset;
|
||
|
bits = n_bits;
|
||
|
#ifdef vax
|
||
|
asm( "extzv r10,r9,(r8),r11" );
|
||
|
#else /* not a vax */
|
||
|
/*
|
||
|
* Get to the first byte.
|
||
|
*/
|
||
|
bp += (r_off >> 3);
|
||
|
r_off &= 7;
|
||
|
/* Get first part (low order bits) */
|
||
|
#ifdef NO_UCHAR
|
||
|
code = ((*bp++ >> r_off) & rmask[8 - r_off]) & 0xff;
|
||
|
#else
|
||
|
code = (*bp++ >> r_off);
|
||
|
#endif /* NO_UCHAR */
|
||
|
bits -= (8 - r_off);
|
||
|
r_off = 8 - r_off; /* now, offset into code word */
|
||
|
/* Get any 8 bit parts in the middle (<=1 for up to 16 bits). */
|
||
|
if ( bits >= 8 ) {
|
||
|
#ifdef NO_UCHAR
|
||
|
code |= (*bp++ & 0xff) << r_off;
|
||
|
#else
|
||
|
code |= *bp++ << r_off;
|
||
|
#endif /* NO_UCHAR */
|
||
|
r_off += 8;
|
||
|
bits -= 8;
|
||
|
}
|
||
|
/* high order bits. */
|
||
|
code |= (*bp & rmask[bits]) << r_off;
|
||
|
#endif /* vax */
|
||
|
offset += n_bits;
|
||
|
|
||
|
return code;
|
||
|
}
|
||
|
|
||
|
#ifdef DEBUG
|
||
|
printcodes()
|
||
|
{
|
||
|
/*
|
||
|
* Just print out codes from input file. For debugging.
|
||
|
*/
|
||
|
code_int code;
|
||
|
int col = 0, bits;
|
||
|
|
||
|
bits = n_bits = INIT_BITS;
|
||
|
maxcode = MAXCODE(n_bits);
|
||
|
free_ent = ((block_compress) ? FIRST : 256 );
|
||
|
while ( ( code = getcode() ) >= 0 ) {
|
||
|
if ( (code == CLEAR) && block_compress ) {
|
||
|
free_ent = FIRST - 1;
|
||
|
clear_flg = 1;
|
||
|
}
|
||
|
else if ( free_ent < maxmaxcode )
|
||
|
free_ent++;
|
||
|
if ( bits != n_bits ) {
|
||
|
fprintf(stderr, "\nChange to %d bits\n", n_bits );
|
||
|
bits = n_bits;
|
||
|
col = 0;
|
||
|
}
|
||
|
fprintf(stderr, "%5d%c", code, (col+=6) >= 74 ? (col = 0, '\n') : ' ' );
|
||
|
}
|
||
|
putc( '\n', stderr );
|
||
|
exit( 0 );
|
||
|
}
|
||
|
|
||
|
code_int sorttab[1<<BITS]; /* sorted pointers into htab */
|
||
|
|
||
|
dump_tab() /* dump string table */
|
||
|
{
|
||
|
register int i, first;
|
||
|
register ent;
|
||
|
#define STACK_SIZE 15000
|
||
|
int stack_top = STACK_SIZE;
|
||
|
register c;
|
||
|
|
||
|
if(do_decomp == 0) { /* compressing */
|
||
|
register int flag = 1;
|
||
|
|
||
|
for(i=0; i<hsize; i++) { /* build sort pointers */
|
||
|
if((long)htabof(i) >= 0) {
|
||
|
sorttab[codetabof(i)] = i;
|
||
|
}
|
||
|
}
|
||
|
first = block_compress ? FIRST : 256;
|
||
|
for(i = first; i < free_ent; i++) {
|
||
|
fprintf(stderr, "%5d: \"", i);
|
||
|
de_stack[--stack_top] = '\n';
|
||
|
de_stack[--stack_top] = '"';
|
||
|
stack_top = in_stack((htabof(sorttab[i])>>maxbits)&0xff,
|
||
|
stack_top);
|
||
|
for(ent=htabof(sorttab[i]) & ((1<<maxbits)-1);
|
||
|
ent > 256;
|
||
|
ent=htabof(sorttab[ent]) & ((1<<maxbits)-1)) {
|
||
|
stack_top = in_stack(htabof(sorttab[ent]) >> maxbits,
|
||
|
stack_top);
|
||
|
}
|
||
|
stack_top = in_stack(ent, stack_top);
|
||
|
fwrite( &de_stack[stack_top], 1, STACK_SIZE-stack_top, stderr);
|
||
|
stack_top = STACK_SIZE;
|
||
|
}
|
||
|
} else if(!debug) { /* decompressing */
|
||
|
|
||
|
for ( i = 0; i < free_ent; i++ ) {
|
||
|
ent = i;
|
||
|
c = tab_suffixof(ent);
|
||
|
if ( isascii(c) && isprint(c) )
|
||
|
fprintf( stderr, "%5d: %5d/'%c' \"",
|
||
|
ent, tab_prefixof(ent), c );
|
||
|
else
|
||
|
fprintf( stderr, "%5d: %5d/\\%03o \"",
|
||
|
ent, tab_prefixof(ent), c );
|
||
|
de_stack[--stack_top] = '\n';
|
||
|
de_stack[--stack_top] = '"';
|
||
|
for ( ; ent != NULL;
|
||
|
ent = (ent >= FIRST ? tab_prefixof(ent) : NULL) ) {
|
||
|
stack_top = in_stack(tab_suffixof(ent), stack_top);
|
||
|
}
|
||
|
fwrite( &de_stack[stack_top], 1, STACK_SIZE - stack_top, stderr );
|
||
|
stack_top = STACK_SIZE;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
int
|
||
|
in_stack(c, stack_top)
|
||
|
register c, stack_top;
|
||
|
{
|
||
|
if ( (isascii(c) && isprint(c) && c != '\\') || c == ' ' ) {
|
||
|
de_stack[--stack_top] = c;
|
||
|
} else {
|
||
|
switch( c ) {
|
||
|
case '\n': de_stack[--stack_top] = 'n'; break;
|
||
|
case '\t': de_stack[--stack_top] = 't'; break;
|
||
|
case '\b': de_stack[--stack_top] = 'b'; break;
|
||
|
case '\f': de_stack[--stack_top] = 'f'; break;
|
||
|
case '\r': de_stack[--stack_top] = 'r'; break;
|
||
|
case '\\': de_stack[--stack_top] = '\\'; break;
|
||
|
default:
|
||
|
de_stack[--stack_top] = '0' + c % 8;
|
||
|
de_stack[--stack_top] = '0' + (c / 8) % 8;
|
||
|
de_stack[--stack_top] = '0' + c / 64;
|
||
|
break;
|
||
|
}
|
||
|
de_stack[--stack_top] = '\\';
|
||
|
}
|
||
|
return stack_top;
|
||
|
}
|
||
|
#endif /* DEBUG */
|
||
|
|
||
|
writeerr()
|
||
|
{
|
||
|
(void)fprintf(stderr, "compress: %s: %s\n",
|
||
|
ofname[0] ? ofname : "stdout", strerror(errno));
|
||
|
(void)unlink(ofname);
|
||
|
exit(1);
|
||
|
}
|
||
|
|
||
|
copystat(ifname, ofname)
|
||
|
char *ifname, *ofname;
|
||
|
{
|
||
|
struct stat statbuf;
|
||
|
int mode;
|
||
|
struct utimbuf tp;
|
||
|
|
||
|
fclose(stdout);
|
||
|
if (stat(ifname, &statbuf)) { /* Get stat on input file */
|
||
|
perror(ifname);
|
||
|
return;
|
||
|
}
|
||
|
if ((statbuf.st_mode & S_IFMT/*0170000*/) != S_IFREG/*0100000*/) {
|
||
|
if(quiet)
|
||
|
fprintf(stderr, "%s: ", ifname);
|
||
|
fprintf(stderr, " -- not a regular file: unchanged");
|
||
|
exit_stat = 1;
|
||
|
perm_stat = 1;
|
||
|
} else if (statbuf.st_nlink > 1) {
|
||
|
if(quiet)
|
||
|
fprintf(stderr, "%s: ", ifname);
|
||
|
fprintf(stderr, " -- has %d other links: unchanged",
|
||
|
statbuf.st_nlink - 1);
|
||
|
exit_stat = 1;
|
||
|
perm_stat = 1;
|
||
|
} else if (exit_stat == 2 && (!force)) { /* No compression: remove file.Z */
|
||
|
if(!quiet)
|
||
|
fprintf(stderr, " -- file unchanged");
|
||
|
} else { /* ***** Successful Compression ***** */
|
||
|
exit_stat = 0;
|
||
|
mode = statbuf.st_mode & 07777;
|
||
|
if (chmod(ofname, mode)) /* Copy modes */
|
||
|
perror(ofname);
|
||
|
chown(ofname, statbuf.st_uid, statbuf.st_gid); /* Copy ownership */
|
||
|
tp.actime = statbuf.st_atime;
|
||
|
tp.modtime = statbuf.st_mtime;
|
||
|
utime(ofname, &tp); /* Update last accessed and modified times */
|
||
|
if (unlink(ifname)) /* Remove input file */
|
||
|
perror(ifname);
|
||
|
if(!quiet)
|
||
|
fprintf(stderr, " -- replaced with %s", ofname);
|
||
|
return; /* Successful return */
|
||
|
}
|
||
|
|
||
|
/* Unsuccessful return -- one of the tests failed */
|
||
|
if (unlink(ofname))
|
||
|
perror(ofname);
|
||
|
}
|
||
|
|
||
|
void
|
||
|
onintr ( )
|
||
|
{
|
||
|
if (!precious)
|
||
|
unlink ( ofname );
|
||
|
exit ( 1 );
|
||
|
}
|
||
|
|
||
|
void
|
||
|
oops ( ) /* wild pointer -- assume bad input */
|
||
|
{
|
||
|
if ( do_decomp )
|
||
|
fprintf ( stderr, "uncompress: corrupt input\n" );
|
||
|
unlink ( ofname );
|
||
|
exit ( 1 );
|
||
|
}
|
||
|
|
||
|
cl_block () /* table clear for block compress */
|
||
|
{
|
||
|
register long int rat;
|
||
|
|
||
|
checkpoint = in_count + CHECK_GAP;
|
||
|
#ifdef DEBUG
|
||
|
if ( debug ) {
|
||
|
fprintf ( stderr, "count: %ld, ratio: ", in_count );
|
||
|
prratio ( stderr, in_count, bytes_out );
|
||
|
fprintf ( stderr, "\n");
|
||
|
}
|
||
|
#endif /* DEBUG */
|
||
|
|
||
|
if(in_count > 0x007fffff) { /* shift will overflow */
|
||
|
rat = bytes_out >> 8;
|
||
|
if(rat == 0) { /* Don't divide by zero */
|
||
|
rat = 0x7fffffff;
|
||
|
} else {
|
||
|
rat = in_count / rat;
|
||
|
}
|
||
|
} else {
|
||
|
rat = (in_count << 8) / bytes_out; /* 8 fractional bits */
|
||
|
}
|
||
|
if ( rat > ratio ) {
|
||
|
ratio = rat;
|
||
|
} else {
|
||
|
ratio = 0;
|
||
|
#ifdef DEBUG
|
||
|
if(verbose)
|
||
|
dump_tab(); /* dump string table */
|
||
|
#endif
|
||
|
cl_hash ( (count_int) hsize );
|
||
|
free_ent = FIRST;
|
||
|
clear_flg = 1;
|
||
|
output ( (code_int) CLEAR );
|
||
|
#ifdef DEBUG
|
||
|
if(debug)
|
||
|
fprintf ( stderr, "clear\n" );
|
||
|
#endif /* DEBUG */
|
||
|
}
|
||
|
}
|
||
|
|
||
|
cl_hash(hsize) /* reset code table */
|
||
|
register count_int hsize;
|
||
|
{
|
||
|
register count_int *htab_p = htab+hsize;
|
||
|
register long i;
|
||
|
register long m1 = -1;
|
||
|
|
||
|
i = hsize - 16;
|
||
|
do { /* might use Sys V memset(3) here */
|
||
|
*(htab_p-16) = m1;
|
||
|
*(htab_p-15) = m1;
|
||
|
*(htab_p-14) = m1;
|
||
|
*(htab_p-13) = m1;
|
||
|
*(htab_p-12) = m1;
|
||
|
*(htab_p-11) = m1;
|
||
|
*(htab_p-10) = m1;
|
||
|
*(htab_p-9) = m1;
|
||
|
*(htab_p-8) = m1;
|
||
|
*(htab_p-7) = m1;
|
||
|
*(htab_p-6) = m1;
|
||
|
*(htab_p-5) = m1;
|
||
|
*(htab_p-4) = m1;
|
||
|
*(htab_p-3) = m1;
|
||
|
*(htab_p-2) = m1;
|
||
|
*(htab_p-1) = m1;
|
||
|
htab_p -= 16;
|
||
|
} while ((i -= 16) >= 0);
|
||
|
for ( i += 16; i > 0; i-- )
|
||
|
*--htab_p = m1;
|
||
|
}
|
||
|
|
||
|
prratio(stream, num, den)
|
||
|
FILE *stream;
|
||
|
long int num, den;
|
||
|
{
|
||
|
register int q; /* Doesn't need to be long */
|
||
|
|
||
|
if(num > 214748L) { /* 2147483647/10000 */
|
||
|
q = num / (den / 10000L);
|
||
|
} else {
|
||
|
q = 10000L * num / den; /* Long calculations, though */
|
||
|
}
|
||
|
if (q < 0) {
|
||
|
putc('-', stream);
|
||
|
q = -q;
|
||
|
}
|
||
|
fprintf(stream, "%d.%02d%%", q / 100, q % 100);
|
||
|
}
|
||
|
|
||
|
usage()
|
||
|
{
|
||
|
(void)fprintf(stderr,
|
||
|
#ifdef DEBUG
|
||
|
"compress [-CDVcdfnv] [-b maxbits] [file ...]\n");
|
||
|
#else
|
||
|
"compress [-Ccdfnv] [-b maxbits] [file ...]\n");
|
||
|
#endif
|
||
|
exit(1);
|
||
|
}
|