xref: /titanic_41/usr/src/cmd/compress/compress.c (revision 355b4669e025ff377602b6fc7caaf30dbc218371)
1 /*
2  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
7 /*	  All Rights Reserved  	*/
8 
9 
10 /*
11  * Copyright (c) 1986 Regents of the University of California.
12  * All rights reserved.  The Berkeley software License Agreement
13  * specifies the terms and conditions for redistribution.
14  */
15 
16 #pragma ident	"%Z%%M%	%I%	%E% SMI"
17 
18 /*
19  * Compress - data compression program
20  */
21 #define	min(a, b)	((a > b) ? b : a)
22 
23 /*
24  * machine variants which require cc -Dmachine:  pdp11, z8000, pcxt
25  */
26 
27 /*
28  * Set USERMEM to the maximum amount of physical user memory available
29  * in bytes.  USERMEM is used to determine the maximum BITS that can be used
30  * for compression.
31  *
32  * SACREDMEM is the amount of physical memory saved for others; compress
33  * will hog the rest.
34  */
35 #ifndef SACREDMEM
36 #define	SACREDMEM	0
37 #endif
38 
39 #ifndef USERMEM
40 #define	USERMEM 	450000	/* default user memory */
41 #endif
42 
43 #ifdef USERMEM
44 #if USERMEM >= (433484+SACREDMEM)
45 #define	PBITS	16
46 #else
47 #if USERMEM >= (229600+SACREDMEM)
48 #define	PBITS	15
49 #else
50 #if USERMEM >= (127536+SACREDMEM)
51 #define	PBITS	14
52 #else
53 #if USERMEM >= (73464+SACREDMEM)
54 #define	PBITS	13
55 #else
56 #define	PBITS	12
57 #endif
58 #endif
59 #endif
60 #endif
61 #undef USERMEM
62 #endif /* USERMEM */
63 
64 #ifdef PBITS		/* Preferred BITS for this memory size */
65 #ifndef BITS
66 #define	BITS PBITS
67 #endif /* BITS */
68 #endif /* PBITS */
69 
70 #if BITS == 16
71 #define	HSIZE	69001		/* 95% occupancy */
72 #endif
73 #if BITS == 15
74 #define	HSIZE	35023		/* 94% occupancy */
75 #endif
76 #if BITS == 14
77 #define	HSIZE	18013		/* 91% occupancy */
78 #endif
79 #if BITS == 13
80 #define	HSIZE	9001		/* 91% occupancy */
81 #endif
82 #if BITS <= 12
83 #define	HSIZE	5003		/* 80% occupancy */
84 #endif
85 
86 #define	OUTSTACKSIZE	(2<<BITS)
87 
88 /*
89  * a code_int must be able to hold 2**BITS values of type int, and also -1
90  */
91 #if BITS > 15
92 typedef long int	code_int;
93 #else
94 typedef int		code_int;
95 #endif
96 
97 typedef long int	count_int;
98 typedef long long	count_long;
99 
100 typedef	unsigned char	char_type;
101 
102 static char_type magic_header[] = { "\037\235" }; /* 1F 9D */
103 
104 /* Defines for third byte of header */
105 #define	BIT_MASK	0x1f
106 #define	BLOCK_MASK	0x80
107 /*
108  * Masks 0x40 and 0x20 are free.  I think 0x20 should mean that there is
109  * a fourth header byte(for expansion).
110  */
111 #define	INIT_BITS 9			/* initial number of bits/code */
112 
113 /*
114  * compress.c - File compression ala IEEE Computer, June 1984.
115  */
116 static char rcs_ident[] =
117 	"$Header: compress.c,v 4.0 85/07/30 12:50:00 joe Release $";
118 
119 #include <stdio.h>
120 #include <ctype.h>
121 #include <signal.h>
122 #include <sys/types.h>
123 #include <sys/stat.h>
124 #include <unistd.h>
125 #include <sys/param.h>
126 #include <stdlib.h>			/* XCU4 */
127 #include <limits.h>
128 #include <libintl.h>
129 #include <locale.h>
130 #include <langinfo.h>
131 #include <string.h>
132 #include <sys/acl.h>
133 #include <utime.h>
134 #include <libgen.h>
135 #include <setjmp.h>
136 #include <strings.h>
137 #include <fcntl.h>
138 #include <dirent.h>
139 #include <aclutils.h>
140 
141 /*
142  * Multi-byte handling for 'y' or 'n'
143  */
144 static char	*yesstr;		/* string contains int'l for "yes" */
145 static char	*nostr;			/* string contains int'l for "yes" */
146 static int	ynsize = 0;		/* # of (multi)bytes for "y" */
147 static char	*yesorno;		/* int'l input for 'y' */
148 
149 static int n_bits;			/* number of bits/code */
150 static int maxbits = BITS;	/* user settable max # bits/code */
151 static code_int maxcode;	/* maximum code, given n_bits */
152 			/* should NEVER generate this code */
153 static code_int maxmaxcode = 1 << BITS;
154 #define	MAXCODE(n_bits)	((1 << (n_bits)) - 1)
155 
156 static count_int htab [OUTSTACKSIZE];
157 static unsigned short codetab [OUTSTACKSIZE];
158 
159 #define	htabof(i)	htab[i]
160 #define	codetabof(i)	codetab[i]
161 static code_int hsize = HSIZE; /* for dynamic table sizing */
162 static off_t	fsize;	/* file size of input file */
163 
164 /*
165  * To save much memory, we overlay the table used by compress() with those
166  * used by decompress().  The tab_prefix table is the same size and type
167  * as the codetab.  The tab_suffix table needs 2**BITS characters.  We
168  * get this from the beginning of htab.  The output stack uses the rest
169  * of htab, and contains characters.  There is plenty of room for any
170  * possible stack (stack used to be 8000 characters).
171  */
172 
173 #define	tab_prefixof(i)		codetabof(i)
174 #define	tab_suffixof(i)		((char_type *)(htab))[i]
175 #define	de_stack		((char_type *)&tab_suffixof(1<<BITS))
176 #define	stack_max		((char_type *)&tab_suffixof(OUTSTACKSIZE))
177 
178 static code_int free_ent = 0; /* first unused entry */
179 static int newline_needed = 0;
180 static int didnt_shrink = 0;
181 static int perm_stat = 0;	/* permanent status */
182 
183 static code_int getcode();
184 
185 	/* Use a 3-byte magic number header, unless old file */
186 static int nomagic = 0;
187 	/* Write output on stdout, suppress messages */
188 static int zcat_flg = 0;	/* use stdout on all files */
189 static int zcat_cmd = 0;	/* zcat cmd */
190 static int use_stdout = 0;	/* set for each file processed */
191 	/* Don't unlink output file on interrupt */
192 static int precious = 1;
193 static int quiet = 1;	/* don't tell me about compression */
194 
195 /*
196  * block compression parameters -- after all codes are used up,
197  * and compression rate changes, start over.
198  */
199 static int block_compress = BLOCK_MASK;
200 static int clear_flg = 0;
201 static long int ratio = 0;
202 #define	CHECK_GAP 10000	/* ratio check interval */
203 static count_long checkpoint = CHECK_GAP;
204 /*
205  * the next two codes should not be changed lightly, as they must not
206  * lie within the contiguous general code space.
207  */
208 #define	FIRST	257	/* first free entry */
209 #define	CLEAR	256	/* table clear output code */
210 
211 static int force = 0;
212 static char ofname [MAXPATHLEN];
213 
214 static int Vflg = 0;
215 static int vflg = 0;
216 static int qflg = 0;
217 static int bflg = 0;
218 static int Fflg = 0;
219 static int dflg = 0;
220 static int cflg = 0;
221 static int Cflg = 0;
222 
223 #ifdef DEBUG
224 int verbose = 0;
225 int debug = 0;
226 #endif /* DEBUG */
227 
228 static void (*oldint)();
229 static int bgnd_flag;
230 
231 static int do_decomp = 0;
232 
233 static char *progname;
234 static char *optstr;
235 /*
236  * Fix lint errors
237  */
238 
239 static char *local_basename(char *);
240 
241 static int  addDotZ(char *, size_t);
242 
243 static void Usage(void);
244 static void cl_block(count_long);
245 static void cl_hash(count_int);
246 static void compress(void);
247 static void copystat(char *, struct stat *, char *);
248 static void decompress(void);
249 static void ioerror(void);
250 static void onintr();
251 static void oops();
252 static void output(code_int);
253 static void prratio(FILE *, count_long, count_long);
254 static void version(void);
255 static int mv_xattrs(char *, char *, int);
256 
257 #ifdef DEBUG
258 static int in_stack(int, int);
259 static void dump_tab(void);
260 static void printcodes(void);
261 #endif
262 
263 /* For error-handling */
264 
265 static jmp_buf env;
266 
267 /* For input and ouput */
268 
269 static FILE *inp;		/* the current input file */
270 static FILE *infile;		/* disk-based input stream */
271 static FILE *outp;		/* current output file */
272 static FILE *outfile;		/* disk-based output stream */
273 
274 /* For output() */
275 
276 static char buf[BITS];
277 
278 static char_type lmask[9] =
279 	{0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80, 0x00};
280 static char_type rmask[9] =
281 	{0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff};
282 
283 /* For compress () */
284 
285 static int offset;
286 static count_long bytes_out;	/* length of compressed output */
287 	/* # of codes output (for debugging) */
288 
289 /* For dump_tab() */
290 
291 #define	STACK_SIZE	15000
292 #ifdef DEBUG
293 code_int sorttab[1<<BITS];	/* sorted pointers into htab */
294 #endif
295 
296 /*
297  * *************************************************************
298  * TAG( main )
299  *
300  * Algorithm from "A Technique for High Performance Data Compression",
301  * Terry A. Welch, IEEE Computer Vol 17, No 6 (June 1984), pp 8-19.
302  *
303  * Usage: compress [-dfvc] [-b bits] [file ...]
304  * Inputs:
305  *	-d:	    If given, decompression is done instead.
306  *
307  *	-c:	    Write output on stdout, don't remove original.
308  *
309  *	-b:	    Parameter limits the max number of bits/code.
310  *
311  *	-f:	    Forces output file to be generated, even if one already
312  *		    exists, and even if no space is saved by compressing.
313  *		    If -f is not used, the user will be prompted if stdin is
314  *		    a tty, otherwise, the output file will not be overwritten.
315  *
316  *  -v:	    Write compression statistics
317  *
318  * 	file ...:   Files to be compressed.  If none specified, stdin
319  *		    is used.
320  * Outputs:
321  *	file.Z:	    Compressed form of file with same mode, owner, and utimes
322  * 	or stdout   (if stdin used as input)
323  *
324  * Assumptions:
325  * When filenames are given, replaces with the compressed version
326  * (.Z suffix) only if the file decreases in size.
327  * Algorithm:
328  * Modified Lempel-Ziv method (LZW).  Basically finds common
329  * substrings and replaces them with a variable size code.  This is
330  * deterministic, and can be done on the fly.  Thus, the decompression
331  * procedure needs no input table, but tracks the way the table was built.
332  */
333 
334 int
335 main(int argc, char *argv[])
336 {
337 	int overwrite = 0;	/* Do not overwrite unless given -f flag */
338 	char tempname[MAXPATHLEN];
339 	char line[LINE_MAX];
340 	char **filelist, **fileptr;
341 	char *cp;
342 	struct stat statbuf;
343 	struct stat ostatbuf;
344 	int ch;				/* XCU4 */
345 	char	*p, *yptr, *nptr;
346 	extern int optind, optopt;
347 	extern char *optarg;
348 	int dash_count = 0;		/* times "-" is on cmdline */
349 
350 	/* XCU4 changes */
351 	(void) setlocale(LC_ALL, "");
352 #if !defined(TEXT_DOMAIN)	/* Should be defined by cc -D */
353 #define	TEXT_DOMAIN "SYS_TEST"	/* Use this only if it weren't */
354 #endif
355 	(void) textdomain(TEXT_DOMAIN);
356 	/* Build multi-byte char for 'y' char */
357 	if ((yptr = nl_langinfo(YESSTR)) == NULL)
358 		yptr = "y";
359 
360 	yesstr = (char *)malloc(strlen(yptr) + 1);
361 	(void) strcpy(yesstr, yptr);
362 	/* Build multi-byte char for 'n' char */
363 	if ((nptr = nl_langinfo(NOSTR)) == NULL)
364 		nptr = "n";
365 
366 	nostr = (char *)malloc(strlen(nptr) + 1);
367 	(void) strcpy(nostr, nptr);
368 
369 	/* Build multi-byte char for input char */
370 	yesorno = (char *)malloc((size_t)ynsize + 1);
371 	ynsize = mblen(yesstr, strlen(yesstr));
372 
373 	/* This bg check only works for sh. */
374 	if ((oldint = signal(SIGINT, SIG_IGN)) != SIG_IGN) {
375 		(void) signal(SIGINT, onintr);
376 		(void) signal(SIGSEGV, oops);
377 	}
378 	bgnd_flag = oldint != SIG_DFL;
379 
380 	/* Allocate room for argv + "-" (if stdin needs to be added) */
381 
382 	filelist = fileptr = (char **)(malloc((argc + 1) * sizeof (*argv)));
383 	*filelist = NULL;
384 
385 	if ((cp = rindex(argv[0], '/')) != 0) {
386 		cp++;
387 	} else {
388 		cp = argv[0];
389 	}
390 
391 	if (strcmp(cp, "uncompress") == 0) {
392 		do_decomp = 1;
393 	} else if (strcmp(cp, "zcat") == 0) {
394 		do_decomp = 1;
395 		zcat_cmd = zcat_flg = 1;
396 	}
397 
398 	progname = local_basename(argv[0]);
399 
400 	/*
401 	 * Argument Processing
402 	 * All flags are optional.
403 	 * -D = > debug
404 	 * -V = > print Version; debug verbose
405 	 * -d = > do_decomp
406 	 * -v = > unquiet
407 	 * -f = > force overwrite of output file
408 	 * -n = > no header: useful to uncompress old files
409 	 * -b	  maxbits => maxbits.  If -b is specified,
410 	 *	  then maxbits MUST be given also.
411 	 * -c = > cat all output to stdout
412 	 * -C = > generate output compatible with compress 2.0.
413 	 * if a string is left, must be an input filename.
414 	 */
415 #ifdef DEBUG
416 	optstr = "b:cCdDfFnqvV";
417 #else
418 	optstr = "b:cCdfFnqvV";
419 #endif
420 
421 	while ((ch = getopt(argc, argv, optstr)) != EOF) {
422 		/* Process all flags in this arg */
423 		switch (ch) {
424 #ifdef DEBUG
425 			case 'D':
426 				debug = 1;
427 				break;
428 			case 'V':
429 				verbose = 1;
430 				version();
431 				break;
432 #else
433 			case 'V':
434 				version();
435 				Vflg++;
436 				break;
437 #endif /* DEBUG */
438 			case 'v':
439 				quiet = 0;
440 				vflg++;
441 				break;
442 			case 'd':
443 				do_decomp = 1;
444 				dflg++;
445 				break;
446 			case 'f':
447 			case 'F':
448 				Fflg++;
449 				overwrite = 1;
450 				force = 1;
451 				break;
452 			case 'n':
453 				nomagic = 1;
454 				break;
455 			case 'C':
456 				Cflg++;
457 				block_compress = 0;
458 				break;
459 			case 'b':
460 				bflg++;
461 				p = optarg;
462 				if (!p) {
463 					(void) fprintf(stderr, gettext(
464 						"Missing maxbits\n"));
465 					Usage();
466 					exit(1);
467 				}
468 				maxbits = strtoul(optarg, &p, 10);
469 				if (*p) {
470 					(void) fprintf(stderr, gettext(
471 						"Missing maxbits\n"));
472 					Usage();
473 					exit(1);
474 				}
475 				break;
476 
477 			case 'c':
478 				cflg++;
479 				zcat_flg = 1;
480 				break;
481 			case 'q':
482 				qflg++;
483 				quiet = 1;
484 				break;
485 			default:
486 				(void) fprintf(stderr, gettext(
487 					"Unknown flag: '%c'\n"), optopt);
488 				Usage();
489 				exit(1);
490 		}
491 	} /* while */
492 
493 	/*
494 	 * Validate zcat syntax
495 	 */
496 
497 	if (zcat_cmd && (Fflg | Cflg | cflg |
498 	    bflg | qflg | dflg | nomagic)) {
499 		(void) fprintf(stderr, gettext(
500 			"Invalid Option\n"));
501 		Usage();
502 		exit(1);
503 	}
504 
505 	/*
506 	 * Process the file list
507 	 */
508 
509 	for (; optind < argc; optind++) {
510 		if (strcmp(argv[optind], "-") == 0) {
511 			dash_count++;
512 		}
513 
514 		*fileptr++ = argv[optind];	/* Build input file list */
515 		*fileptr = NULL;
516 	}
517 
518 	if (dash_count > 1) {
519 		(void) fprintf(stderr,
520 			gettext("%s may only appear once in the file"
521 				" list\n"), "\"-\"");
522 		exit(1);
523 	}
524 
525 	if (fileptr - filelist == 0) {
526 		*fileptr++ = "-";
527 		*fileptr = NULL;
528 	}
529 
530 	if (fileptr - filelist > 1 && cflg && !do_decomp) {
531 		(void) fprintf(stderr,
532 			gettext("compress: only one file may be compressed"
533 				" to stdout\n"));
534 		exit(1);
535 	}
536 
537 	if (maxbits < INIT_BITS)
538 		maxbits = INIT_BITS;
539 	if (maxbits > BITS)
540 		maxbits = BITS;
541 	maxmaxcode = 1 << maxbits;
542 
543 	/* Need to open something to close with freopen later */
544 
545 	if ((infile = fopen("/dev/null", "r")) == NULL) {
546 		(void) fprintf(stderr, gettext("Error opening /dev/null for "
547 			"input\n"));
548 		exit(1);
549 	}
550 
551 	if ((outfile = fopen("/dev/null", "w")) == NULL) {
552 		(void) fprintf(stderr, gettext("Error opening /dev/null for "
553 			"output\n"));
554 		exit(1);
555 	}
556 
557 	for (fileptr = filelist; *fileptr; fileptr++) {
558 		int jmpval = 0;
559 		didnt_shrink = 0;
560 		newline_needed = 0;
561 
562 		if (do_decomp) {
563 			/* DECOMPRESSION */
564 
565 			if (strcmp(*fileptr, "-") == 0) {
566 				/* process stdin */
567 				inp = stdin;
568 				outp = stdout;
569 				use_stdout = 1;
570 				*fileptr = "stdin"; /* for error messages */
571 			} else {
572 				/* process the named file */
573 
574 				inp = infile;
575 				outp = outfile;
576 				use_stdout = 0;
577 
578 				if (zcat_flg) {
579 					use_stdout = 1;
580 					outp = stdout;
581 				}
582 
583 				/* Check for .Z suffix */
584 
585 				if (strcmp(*fileptr +
586 				    strlen(*fileptr) - 2, ".Z") != 0) {
587 					/* No .Z: tack one on */
588 
589 					if (strlcpy(tempname, *fileptr,
590 						sizeof (tempname)) >=
591 						sizeof (tempname)) {
592 						(void) fprintf(stderr,
593 						    gettext("%s: filename "
594 							"too long\n"),
595 							*fileptr);
596 						perm_stat = 1;
597 						continue;
598 					}
599 
600 					if (addDotZ(tempname,
601 					    sizeof (tempname)) < 0) {
602 						perm_stat = 1;
603 						continue;
604 					}
605 
606 					*fileptr = tempname;
607 				}
608 
609 				/* Open input file */
610 
611 				if (stat(*fileptr, &statbuf) < 0) {
612 					perror(*fileptr);
613 					perm_stat = 1;
614 					continue;
615 				}
616 
617 				if ((freopen(*fileptr, "r", inp)) == NULL) {
618 					perror(*fileptr);
619 					perm_stat = 1;
620 					continue;
621 				}
622 			}
623 
624 			/* Check the magic number */
625 
626 			if (nomagic == 0) {
627 				if ((getc(inp) !=
628 				    (magic_header[0] & 0xFF)) ||
629 				    (getc(inp) !=
630 				    (magic_header[1] & 0xFF))) {
631 					(void) fprintf(stderr, gettext(
632 						"%s: not in compressed "
633 						"format\n"),
634 						*fileptr);
635 					perm_stat = 1;
636 					continue;
637 				}
638 
639 				/* set -b from file */
640 				if ((maxbits = getc(inp)) == EOF &&
641 				    ferror(inp)) {
642 					perror(*fileptr);
643 					perm_stat = 1;
644 					continue;
645 				}
646 
647 				block_compress = maxbits & BLOCK_MASK;
648 				maxbits &= BIT_MASK;
649 				maxmaxcode = 1 << maxbits;
650 
651 				if (maxbits > BITS) {
652 					(void) fprintf(stderr,
653 						gettext("%s: compressed "
654 							"with %d bits, "
655 							"can only handle"
656 							" %d bits\n"),
657 						*fileptr, maxbits, BITS);
658 					perm_stat = 1;
659 					continue;
660 				}
661 			}
662 
663 			if (!use_stdout) {
664 				/* Generate output filename */
665 
666 				if (strlcpy(ofname, *fileptr,
667 					    sizeof (ofname)) >=
668 				    sizeof (ofname)) {
669 					(void) fprintf(stderr,
670 						gettext("%s: filename "
671 							"too long\n"),
672 						*fileptr);
673 					perm_stat = 1;
674 					continue;
675 				}
676 
677 				/* Strip off .Z */
678 
679 				ofname[strlen(*fileptr) - 2] = '\0';
680 			}
681 		} else {
682 			/* COMPRESSION */
683 
684 			if (strcmp(*fileptr, "-") == 0) {
685 				/* process stdin */
686 				inp = stdin;
687 				outp = stdout;
688 				use_stdout = 1;
689 				*fileptr = "stdin"; /* for error messages */
690 
691 				/* Use the largest possible hash table */
692 				hsize =  HSIZE;
693 			} else {
694 				/* process the named file */
695 
696 				inp = infile;
697 				outp = outfile;
698 				use_stdout = 0;
699 
700 				if (zcat_flg) {
701 					use_stdout = 1;
702 					outp = stdout;
703 				}
704 
705 				if (strcmp(*fileptr +
706 				    strlen(*fileptr) - 2, ".Z") == 0) {
707 					(void) fprintf(stderr, gettext(
708 						"%s: already has .Z "
709 						"suffix -- no change\n"),
710 						*fileptr);
711 					perm_stat = 1;
712 					continue;
713 				}
714 				/* Open input file */
715 
716 				if (stat(*fileptr, &statbuf) < 0) {
717 					perror(*fileptr);
718 					perm_stat = 1;
719 					continue;
720 				}
721 
722 				if ((freopen(*fileptr, "r", inp)) == NULL) {
723 					perror(*fileptr);
724 					perm_stat = 1;
725 					continue;
726 				}
727 
728 				fsize = (off_t)statbuf.st_size;
729 
730 				/*
731 				 * tune hash table size for small
732 				 * files -- ad hoc,
733 				 * but the sizes match earlier #defines, which
734 				 * serve as upper bounds on the number of
735 				 * output codes.
736 				 */
737 				hsize = HSIZE;
738 				if (fsize < (1 << 12))
739 					hsize = min(5003, HSIZE);
740 				else if (fsize < (1 << 13))
741 					hsize = min(9001, HSIZE);
742 				else if (fsize < (1 << 14))
743 					hsize = min(18013, HSIZE);
744 				else if (fsize < (1 << 15))
745 					hsize = min(35023, HSIZE);
746 				else if (fsize < 47000)
747 					hsize = min(50021, HSIZE);
748 
749 				if (!use_stdout) {
750 					/* Generate output filename */
751 
752 					if (strlcpy(ofname, *fileptr,
753 						sizeof (ofname)) >=
754 						sizeof (ofname)) {
755 						(void) fprintf(stderr,
756 						    gettext("%s: filename "
757 							"too long\n"),
758 							*fileptr);
759 						perm_stat = 1;
760 						continue;
761 					}
762 
763 					if (addDotZ(ofname,
764 						sizeof (ofname)) < 0) {
765 						perm_stat = 1;
766 						continue;
767 					}
768 				}
769 			}
770 		}	/* if (do_decomp) */
771 
772 		/* Check for overwrite of existing file */
773 
774 		if (!overwrite && !use_stdout) {
775 			if (stat(ofname, &ostatbuf) == 0) {
776 				yesorno[ynsize] = (char)NULL;
777 				(void) fprintf(stderr, gettext(
778 					"%s already exists;"), ofname);
779 				if (bgnd_flag == 0 && isatty(2)) {
780 					int cin;
781 
782 					(void) fprintf(stderr, gettext(
783 						" do you wish to overwr"
784 						"ite %s (%s or %s)? "),
785 						ofname, yesstr, nostr);
786 					(void) fflush(stderr);
787 					for (cin = 0; cin < LINE_MAX;
788 					    cin++)
789 						line[cin] = 0;
790 					(void) read(2, line, LINE_MAX);
791 					(void) strncpy(yesorno, line,
792 						ynsize);
793 
794 					if (!((strncmp(yesstr, yesorno,
795 						ynsize) == 0) ||
796 						(yesorno[0] == 'y') ||
797 						(yesorno[0] == 'Y'))) {
798 						(void) fprintf(stderr,
799 							gettext(
800 							"\tnot overwri"
801 							"tten\n"));
802 						continue;
803 					}
804 				} else {
805 					/*
806 					 * XPG4: Assertion 1009
807 					 * Standard input is not
808 					 * terminal, and no '-f',
809 					 * and file exists.
810 					 */
811 
812 					(void) fprintf(stderr, gettext(
813 						"%s: File exists, -f not"
814 						" specified, and ru"
815 						"nning in the backgro"
816 						"und.\n"), *fileptr);
817 					perm_stat = 1;
818 					continue;
819 				}
820 			}
821 		}
822 		if (!use_stdout) {
823 			if (pathconf(ofname, _PC_XATTR_EXISTS) == 1) {
824 				(void) unlink(ofname);
825 			}
826 			/* Open output file */
827 			if (freopen(ofname, "w", outp) == NULL) {
828 				perror(ofname);
829 				perm_stat = 1;
830 				continue;
831 			}
832 			precious = 0;
833 			if (!quiet) {
834 				(void) fprintf(stderr, "%s: ",
835 					*fileptr);
836 				newline_needed = 1;
837 			}
838 		} else if (!quiet && !do_decomp) {
839 			(void) fprintf(stderr, "%s: ",
840 				*fileptr);
841 				newline_needed = 1;
842 		}
843 
844 		/* Actually do the compression/decompression */
845 
846 		if ((jmpval = setjmp(env)) == 0) {
847 			/* We'll see how things go */
848 #ifndef DEBUG
849 			if (do_decomp == 0)  {
850 				compress();
851 			} else {
852 				decompress();
853 			}
854 #else
855 			if (do_decomp == 0)  {
856 				compress();
857 			} else if (debug == 0)  {
858 				decompress();
859 			} else {
860 				printcodes();
861 			}
862 
863 			if (verbose) {
864 				dump_tab();
865 			}
866 #endif
867 		} else {
868 			/*
869 			 * Things went badly - clean up and go on.
870 			 * jmpval's values break down as follows:
871 			 *   1 == message determined by ferror() values.
872 			 *   2 == input problem message needed.
873 			 *   3 == output problem message needed.
874 			 */
875 
876 			if (ferror(inp) || jmpval == 2) {
877 				if (do_decomp) {
878 					(void) fprintf(stderr, gettext(
879 						"uncompress: %s: corrupt"
880 						" input\n"), *fileptr);
881 				} else {
882 					perror(*fileptr);
883 				}
884 			}
885 
886 			if (ferror(outp) || jmpval == 3) {
887 				/* handle output errors */
888 
889 				if (use_stdout) {
890 					perror("");
891 				} else {
892 					perror(ofname);
893 				}
894 			}
895 
896 			if (ofname[0] != '\0') {
897 				if (unlink(ofname) < 0)  {
898 					perror(ofname);
899 				}
900 
901 				ofname[0] = '\0';
902 			}
903 
904 			perm_stat = 1;
905 			continue;
906 		}
907 
908 		/* Things went well */
909 
910 		if (!use_stdout) {
911 				/* Copy stats */
912 			copystat(*fileptr, &statbuf, ofname);
913 			precious = 1;
914 			if (newline_needed) {
915 				(void) putc('\n', stderr);
916 			}
917 			/*
918 			 * Print the info. for unchanged file
919 			 * when no -v
920 			 */
921 
922 			if (didnt_shrink) {
923 				if (!force && perm_stat == 0) {
924 					if (quiet) {
925 						(void) fprintf(stderr, gettext(
926 							"%s: -- file "
927 							"unchanged\n"),
928 							*fileptr);
929 					}
930 
931 					perm_stat = 2;
932 				}
933 			}
934 		} else {
935 			if (didnt_shrink && !force && perm_stat == 0) {
936 				perm_stat = 2;
937 			}
938 
939 			if (newline_needed) {
940 				(void) fprintf(stderr, "\n");
941 			}
942 		}
943 	}	/* for */
944 
945 	return (perm_stat);
946 }
947 
948 static void
949 cinterr(int hshift)
950 {
951 	/* we have exceeded the hash table */
952 	(void) fprintf(stderr,
953 		"internal error: hashtable exceeded - hsize = %ld\n", hsize);
954 	(void) fprintf(stderr, "hshift = %d, %d\n", hshift, (1 << hshift) -1);
955 	(void) fprintf(stderr, "maxbits = %d\n", maxbits);
956 	(void) fprintf(stderr, "n_bits = %d\n", n_bits);
957 	(void) fprintf(stderr, "maxcode = %ld\n", maxcode);
958 	longjmp(env, 1);
959 }
960 
961 static code_int
962 adjusti(code_int i, code_int hsize_reg)
963 {
964 	while (i < 0) {
965 		i += hsize_reg;
966 	}
967 
968 	while (i >= hsize_reg) {
969 		i -= hsize_reg;
970 	}
971 	return (i);
972 }
973 
974 /*
975  * compress inp to outp
976  *
977  * Algorithm:  use open addressing double hashing(no chaining) on the
978  * prefix code / next character combination.  We do a variant of Knuth's
979  * algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime
980  * secondary probe.  Here, the modular division first probe is gives way
981  * to a faster exclusive-or manipulation.  Also do block compression with
982  * an adaptive reset, whereby the code table is cleared when the compression
983  * ratio decreases, but after the table fills.  The variable-length output
984  * codes are re-sized at this point, and a special CLEAR code is generated
985  * for the decompressor.  Late addition:  construct the table according to
986  * file size for noticeable speed improvement on small files.  Please direct
987  * questions about this implementation to ames!jaw.
988  */
989 
990 static void
991 compress()
992 {
993 	long fcode;
994 	code_int i = 0;
995 	int c;
996 	code_int ent;
997 	int disp;
998 	code_int hsize_reg;
999 	int hshift;
1000 	int probecnt;
1001 	count_long in_count;
1002 	uint32_t inchi, inclo;
1003 	int maxbits_reg;
1004 	FILE *fin = inp;
1005 #ifdef DEBUG
1006 	count_long out_count = 0;
1007 #endif
1008 
1009 	if (nomagic == 0) {
1010 		if ((putc(magic_header[0], outp) == EOF ||
1011 		    putc(magic_header[1], outp) == EOF ||
1012 		    putc((char)(maxbits | block_compress),
1013 			outp) == EOF) &&
1014 		    ferror(outp)) {
1015 			ioerror();
1016 		}
1017 	}
1018 
1019 	offset = 0;
1020 	bytes_out = 3;		/* includes 3-byte header mojo */
1021 	clear_flg = 0;
1022 	ratio = 0;
1023 	in_count = 1;
1024 	inchi = 0;
1025 	inclo = 1;
1026 	checkpoint = CHECK_GAP;
1027 	maxcode = MAXCODE(n_bits = INIT_BITS);
1028 	free_ent = ((block_compress) ? FIRST : 256);
1029 
1030 	if ((ent = getc(fin)) == EOF && ferror(fin)) {
1031 		ioerror();
1032 	}
1033 
1034 	hshift = 0;
1035 
1036 	for (fcode = (long)hsize;  fcode < 65536L; fcode *= 2L)
1037 		hshift++;
1038 
1039 	hshift = 8 - hshift;		/* set hash code range bound */
1040 
1041 	hsize_reg = hsize;
1042 	maxbits_reg = maxbits;
1043 
1044 	cl_hash((count_int) hsize_reg);		/* clear hash table */
1045 
1046 	while ((c = getc(fin)) != EOF) {
1047 		if (++inclo == 0)
1048 			inchi++;
1049 		fcode = (long)(((long)c << maxbits_reg) + ent);
1050 		i = ((c << hshift) ^ ent);	/* xor hashing */
1051 
1052 		if ((unsigned int)i >= hsize_reg)
1053 			i = adjusti(i, hsize_reg);
1054 
1055 		if (htabof(i) == fcode) {
1056 			ent = codetabof(i);
1057 			continue;
1058 		} else if ((long)htabof(i) < 0) {
1059 			/* empty slot */
1060 			goto nomatch;
1061 		}
1062 
1063 		/* secondary hash (after G. Knott) */
1064 		disp = hsize_reg - i;
1065 
1066 		if (i == 0) {
1067 			disp = 1;
1068 		}
1069 
1070 		probecnt = 0;
1071 	probe:
1072 		if (++probecnt > hsize_reg)
1073 			cinterr(hshift);
1074 
1075 		if ((i -= disp) < 0) {
1076 			while (i < 0)
1077 				i += hsize_reg;
1078 		}
1079 
1080 		if (htabof(i) == fcode) {
1081 			ent = codetabof(i);
1082 			continue;
1083 		}
1084 
1085 		if ((long)htabof(i) > 0) {
1086 			goto probe;
1087 		}
1088 	nomatch:
1089 		output((code_int) ent);
1090 #ifdef DEBUG
1091 		out_count++;
1092 #endif
1093 		ent = c;
1094 		if (free_ent < maxmaxcode) {
1095 			codetabof(i) = free_ent++;
1096 			/* code -> hashtable */
1097 			htabof(i) = fcode;
1098 		} else {
1099 			in_count = ((long long)inchi<<32|inclo);
1100 			if ((count_long)in_count >=
1101 			    (count_long)checkpoint && block_compress) {
1102 				cl_block(in_count);
1103 			}
1104 		}
1105 	}
1106 
1107 	in_count = ((long long)inchi<<32|inclo);
1108 
1109 	if (ferror(fin) != 0) {
1110 		ioerror();
1111 	}
1112 
1113 	/*
1114 	 * Put out the final code.
1115 	 */
1116 	output((code_int)ent);
1117 #ifdef DEBUG
1118 	out_count++;
1119 #endif
1120 
1121 	output((code_int)-1);
1122 
1123 	/*
1124 	 * Print out stats on stderr
1125 	 */
1126 	if (!quiet) {
1127 #ifdef DEBUG
1128 		(void) fprintf(stderr,
1129 			"%lld chars in, %lld codes (%lld bytes) out, "
1130 			"compression factor: ",
1131 			(count_long)in_count, (count_long)out_count,
1132 			(count_long) bytes_out);
1133 		prratio(stderr, (count_long)in_count,
1134 			(count_long)bytes_out);
1135 		(void) fprintf(stderr, "\n");
1136 		(void) fprintf(stderr, "\tCompression as in compact: ");
1137 		prratio(stderr,
1138 			(count_long)in_count-(count_long)bytes_out,
1139 			(count_long)in_count);
1140 		(void) fprintf(stderr, "\n");
1141 		(void) fprintf(stderr,
1142 			"\tLargest code (of last block) was %d"
1143 			" (%d bits)\n",
1144 			free_ent - 1, n_bits);
1145 #else /* !DEBUG */
1146 		(void) fprintf(stderr, gettext("Compression: "));
1147 		prratio(stderr,
1148 			(count_long)in_count-(count_long)bytes_out,
1149 			(count_long)in_count);
1150 #endif /* DEBUG */
1151 	}
1152 	/* report if no savings */
1153 	if ((count_long)bytes_out > (count_long)in_count) {
1154 		didnt_shrink = 1;
1155 	}
1156 }
1157 
1158 /*
1159  * **************************************************************
1160  * TAG(output)
1161  *
1162  * Output the given code.
1163  * Inputs:
1164  * 	code:	A n_bits-bit integer.  If == -1, then EOF.  This assumes
1165  *		that n_bits = < (long)wordsize - 1.
1166  * Outputs:
1167  * 	Outputs code to the file.
1168  * Assumptions:
1169  *	Chars are 8 bits long.
1170  * Algorithm:
1171  * 	Maintain a BITS character long buffer(so that 8 codes will
1172  * fit in it exactly).  Use the VAX insv instruction to insert each
1173  * code in turn.  When the buffer fills up empty it and start over.
1174  */
1175 
1176 static void
1177 output(code_int code)
1178 {
1179 #ifdef DEBUG
1180 	static int col = 0;
1181 #endif /* DEBUG */
1182 
1183 	int r_off = offset, bits = n_bits;
1184 	char *bp = buf;
1185 
1186 #ifdef DEBUG
1187 	if (verbose)
1188 		(void) fprintf(stderr, "%5d%c", code,
1189 			(col += 6) >= 74 ? (col = 0, '\n') : ' ');
1190 #endif /* DEBUG */
1191 	if (code >= 0) {
1192 		/*
1193 		 * byte/bit numbering on the VAX is simulated
1194 		 * by the following code
1195 		 */
1196 		/*
1197 		 * Get to the first byte.
1198 		 */
1199 		bp += (r_off >> 3);
1200 		r_off &= 7;
1201 		/*
1202 		 * Since code is always >= 8 bits, only need to mask the first
1203 		 * hunk on the left.
1204 		 */
1205 		*bp = (*bp & rmask[r_off]) | (code << r_off) & lmask[r_off];
1206 		bp++;
1207 		bits -= (8 - r_off);
1208 		code >>= 8 - r_off;
1209 		/*
1210 		 * Get any 8 bit parts in the middle (<=1 for up to 16
1211 		 * bits).
1212 		 */
1213 		if (bits >= 8) {
1214 			*bp++ = code;
1215 			code >>= 8;
1216 			bits -= 8;
1217 		}
1218 		/* Last bits. */
1219 		if (bits)
1220 			*bp = code;
1221 		offset += n_bits;
1222 		if (offset == (n_bits << 3)) {
1223 			bp = buf;
1224 			bits = n_bits;
1225 			bytes_out += bits;
1226 			do {
1227 				if (putc(*bp, outp) == EOF &&
1228 				    ferror(outp)) {
1229 					ioerror();
1230 				}
1231 				bp++;
1232 			} while (--bits);
1233 			offset = 0;
1234 		}
1235 
1236 		/*
1237 		 * If the next entry is going to be too big for the code size,
1238 		 * then increase it, if possible.
1239 		 */
1240 		if (free_ent > maxcode || (clear_flg > 0)) {
1241 			/*
1242 			 * Write the whole buffer, because the input
1243 			 * side won't discover the size increase until
1244 			 * after it has read it.
1245 			 */
1246 			if (offset > 0) {
1247 				if (fwrite(buf, 1, n_bits, outp) != n_bits) {
1248 					longjmp(env, 3);
1249 				}
1250 				bytes_out += n_bits;
1251 			}
1252 			offset = 0;
1253 
1254 			if (clear_flg) {
1255 				maxcode = MAXCODE(n_bits = INIT_BITS);
1256 				clear_flg = 0;
1257 			} else {
1258 				n_bits++;
1259 				if (n_bits == maxbits)
1260 					maxcode = maxmaxcode;
1261 				else
1262 					maxcode = MAXCODE(n_bits);
1263 			}
1264 #ifdef DEBUG
1265 			if (debug) {
1266 				(void) fprintf(stderr,
1267 					"\nChange to %d bits\n", n_bits);
1268 				col = 0;
1269 			}
1270 #endif /* DEBUG */
1271 		}
1272 	} else {
1273 		/*
1274 		 * At EOF, write the rest of the buffer.
1275 		 */
1276 		if (offset > 0) {
1277 			if (fwrite(buf, 1, (offset + 7) / 8, outp) == 0 &&
1278 			    ferror(outp)) {
1279 				ioerror();
1280 			}
1281 			bytes_out += (offset + 7) / 8;
1282 		}
1283 		offset = 0;
1284 		(void) fflush(outp);
1285 #ifdef DEBUG
1286 		if (verbose)
1287 			(void) fprintf(stderr, "\n");
1288 #endif /* DEBUG */
1289 		if (ferror(outp))
1290 			ioerror();
1291 	}
1292 }
1293 
1294 /*
1295  * Decompress inp to outp.  This routine adapts to the codes in the
1296  * file building the "string" table on-the-fly; requiring no table to
1297  * be stored in the compressed file.  The tables used herein are shared
1298  * with those of the compress() routine.  See the definitions above.
1299  */
1300 
1301 static void
1302 decompress()
1303 {
1304 	char_type *stackp, *stack_lim;
1305 	int finchar;
1306 	code_int code, oldcode, incode;
1307 	FILE *fout = outp;
1308 
1309 	/*
1310 	 * As above, initialize the first 256 entries in the table.
1311 	 */
1312 	maxcode = MAXCODE(n_bits = INIT_BITS);
1313 	for (code = 255; code >= 0; code--) {
1314 		tab_prefixof(code) = 0;
1315 		tab_suffixof(code) = (char_type)code;
1316 	}
1317 	free_ent = ((block_compress) ? FIRST : 256);
1318 
1319 	finchar = oldcode = getcode();
1320 	if (oldcode == -1)	/* EOF already? */
1321 		return;			/* Get out of here */
1322 	/* first code must be 8 bits = char */
1323 	if (putc((char)finchar, outp) == EOF && ferror(outp)) {
1324 		/* Crash if can't write */
1325 		ioerror();
1326 	}
1327 	stackp = de_stack;
1328 	stack_lim = stack_max;
1329 
1330 	while ((code = getcode()) > -1) {
1331 
1332 		if ((code == CLEAR) && block_compress) {
1333 			for (code = 255; code >= 0; code--)
1334 			tab_prefixof(code) = 0;
1335 			clear_flg = 1;
1336 			free_ent = FIRST - 1;
1337 			if ((code = getcode()) == -1)	/* O, untimely death! */
1338 				break;
1339 		}
1340 		incode = code;
1341 		/*
1342 		 * Special case for KwKwK string.
1343 		 */
1344 		if (code >= free_ent) {
1345 			if (stackp < stack_lim) {
1346 				*stackp++ = (char_type) finchar;
1347 				code = oldcode;
1348 			} else {
1349 				/* badness */
1350 				longjmp(env, 2);
1351 			}
1352 		}
1353 
1354 		/*
1355 		 * Generate output characters in reverse order
1356 		 */
1357 		while (code >= 256) {
1358 			if (stackp < stack_lim) {
1359 				*stackp++ = tab_suffixof(code);
1360 				code = tab_prefixof(code);
1361 			} else {
1362 				/* badness */
1363 				longjmp(env, 2);
1364 			}
1365 		}
1366 		*stackp++ = finchar = tab_suffixof(code);
1367 
1368 		/*
1369 		 * And put them out in forward order
1370 		 */
1371 		do {
1372 			stackp--;
1373 			(void) putc(*stackp, fout);
1374 		} while (stackp > de_stack);
1375 
1376 		if (ferror(fout))
1377 			ioerror();
1378 
1379 		/*
1380 		 * Generate the new entry.
1381 		 */
1382 		if ((code = free_ent) < maxmaxcode) {
1383 			tab_prefixof(code) = (unsigned short) oldcode;
1384 			tab_suffixof(code) = (char_type) finchar;
1385 			free_ent = code+1;
1386 		}
1387 		/*
1388 		 * Remember previous code.
1389 		 */
1390 		oldcode = incode;
1391 	}
1392 	(void) fflush(outp);
1393 	if (ferror(outp))
1394 		ioerror();
1395 }
1396 
1397 /*
1398  * **************************************************************
1399  * TAG( getcode )
1400  *
1401  * Read one code from the standard input.  If EOF, return -1.
1402  * Inputs:
1403  * 	inp
1404  * Outputs:
1405  * 	code or -1 is returned.
1406  */
1407 
1408 code_int
1409 getcode() {
1410 	code_int code;
1411 	static int offset = 0, size = 0;
1412 	static char_type buf[BITS];
1413 	int r_off, bits;
1414 	char_type *bp = buf;
1415 
1416 	if (clear_flg > 0 || offset >= size || free_ent > maxcode) {
1417 		/*
1418 		 * If the next entry will be too big for the current code
1419 		 * size, then we must increase the size.  This implies reading
1420 		 * a new buffer full, too.
1421 		 */
1422 		if (free_ent > maxcode) {
1423 			n_bits++;
1424 			if (n_bits == maxbits)
1425 				/* won't get any bigger now */
1426 				maxcode = maxmaxcode;
1427 			else
1428 				maxcode = MAXCODE(n_bits);
1429 		}
1430 		if (clear_flg > 0) {
1431 			maxcode = MAXCODE(n_bits = INIT_BITS);
1432 			clear_flg = 0;
1433 		}
1434 		size = fread(buf, 1, n_bits, inp);
1435 
1436 		if (size <= 0) {
1437 			if (feof(inp)) {
1438 				/* end of file */
1439 				return (-1);
1440 			} else if (ferror(inp)) {
1441 				ioerror();
1442 			}
1443 		}
1444 
1445 		offset = 0;
1446 		/* Round size down to integral number of codes */
1447 		size = (size << 3) - (n_bits - 1);
1448 	}
1449 	r_off = offset;
1450 	bits = n_bits;
1451 	/*
1452 	 * Get to the first byte.
1453 	 */
1454 	bp += (r_off >> 3);
1455 	r_off &= 7;
1456 	/* Get first part (low order bits) */
1457 	code = (*bp++ >> r_off);
1458 	bits -= (8 - r_off);
1459 	r_off = 8 - r_off;		/* now, offset into code word */
1460 	/* Get any 8 bit parts in the middle (<=1 for up to 16 bits). */
1461 	if (bits >= 8) {
1462 		code |= *bp++ << r_off;
1463 		r_off += 8;
1464 		bits -= 8;
1465 	}
1466 	/* high order bits. */
1467 	code |= (*bp & rmask[bits]) << r_off;
1468 	offset += n_bits;
1469 
1470 	return (code);
1471 }
1472 
1473 #ifdef DEBUG
1474 static void
1475 printcodes()
1476 {
1477 	/*
1478 	 * Just print out codes from input file.  For debugging.
1479 	 */
1480 	code_int code;
1481 	int col = 0, bits;
1482 
1483 	bits = n_bits = INIT_BITS;
1484 	maxcode = MAXCODE(n_bits);
1485 	free_ent = ((block_compress) ? FIRST : 256);
1486 	while ((code = getcode()) >= 0) {
1487 		if ((code == CLEAR) && block_compress) {
1488 			free_ent = FIRST - 1;
1489 			clear_flg = 1;
1490 		} else if (free_ent < maxmaxcode)
1491 			free_ent++;
1492 		if (bits != n_bits) {
1493 			(void) fprintf(stderr, "\nChange to %d bits\n", n_bits);
1494 			bits = n_bits;
1495 			col = 0;
1496 		}
1497 		(void) fprintf(stderr, "%5d%c",
1498 			code, (col += 6) >= 74 ? (col = 0, '\n') : ' ');
1499 	}
1500 	(void) putc('\n', stderr);
1501 }
1502 
1503 #endif /* DEBUG */
1504 
1505 #ifdef DEBUG
1506 static void
1507 dump_tab()	/* dump string table */
1508 {
1509 	int i, first;
1510 	int ent;
1511 	int stack_top = STACK_SIZE;
1512 	int c;
1513 
1514 	if (do_decomp == 0) {	/* compressing */
1515 		int flag = 1;
1516 
1517 		for (i = 0; i < hsize; i++) {	/* build sort pointers */
1518 			if ((long)htabof(i) >= 0) {
1519 				sorttab[codetabof(i)] = i;
1520 			}
1521 		}
1522 		first = block_compress ? FIRST : 256;
1523 		for (i = first; i < free_ent; i++) {
1524 			(void) fprintf(stderr, "%5d: \"", i);
1525 			de_stack[--stack_top] = '\n';
1526 			de_stack[--stack_top] = '"';
1527 			stack_top =
1528 				in_stack((htabof(sorttab[i]) >> maxbits) & 0xff,
1529 					stack_top);
1530 			for (ent = htabof(sorttab[i]) & ((1 << maxbits) -1);
1531 				ent > 256;
1532 				ent = htabof(sorttab[ent]) & ((1<<maxbits)-1)) {
1533 				stack_top = in_stack(
1534 					htabof(sorttab[ent]) >> maxbits,
1535 					stack_top);
1536 			}
1537 			stack_top = in_stack(ent, stack_top);
1538 			(void) fwrite(&de_stack[stack_top], 1,
1539 				STACK_SIZE - stack_top, stderr);
1540 			stack_top = STACK_SIZE;
1541 		}
1542 	} else if (!debug) {	/* decompressing */
1543 
1544 		for (i = 0; i < free_ent; i++) {
1545 			ent = i;
1546 			c = tab_suffixof(ent);
1547 			if (isascii(c) && isprint(c))
1548 				(void) fprintf(stderr, "%5d: %5d/'%c'  \"",
1549 					ent, tab_prefixof(ent), c);
1550 			else
1551 				(void) fprintf(stderr, "%5d: %5d/\\%03o \"",
1552 					ent, tab_prefixof(ent), c);
1553 			de_stack[--stack_top] = '\n';
1554 			de_stack[--stack_top] = '"';
1555 			for (; ent != NULL;
1556 				ent = (ent >= FIRST ? tab_prefixof(ent) :
1557 						NULL)) {
1558 				stack_top = in_stack(tab_suffixof(ent),
1559 								stack_top);
1560 			}
1561 			(void) fwrite(&de_stack[stack_top], 1,
1562 				STACK_SIZE - stack_top, stderr);
1563 			stack_top = STACK_SIZE;
1564 		}
1565 	}
1566 }
1567 
1568 #endif /* DEBUG */
1569 #ifdef DEBUG
1570 static int
1571 in_stack(int c, int stack_top)
1572 {
1573 	if ((isascii(c) && isprint(c) && c != '\\') || c == ' ') {
1574 		de_stack[--stack_top] = c;
1575 	} else {
1576 		switch (c) {
1577 		case '\n': de_stack[--stack_top] = 'n'; break;
1578 		case '\t': de_stack[--stack_top] = 't'; break;
1579 		case '\b': de_stack[--stack_top] = 'b'; break;
1580 		case '\f': de_stack[--stack_top] = 'f'; break;
1581 		case '\r': de_stack[--stack_top] = 'r'; break;
1582 		case '\\': de_stack[--stack_top] = '\\'; break;
1583 		default:
1584 			de_stack[--stack_top] = '0' + c % 8;
1585 			de_stack[--stack_top] = '0' + (c / 8) % 8;
1586 			de_stack[--stack_top] = '0' + c / 64;
1587 			break;
1588 		}
1589 		de_stack[--stack_top] = '\\';
1590 	}
1591 	return (stack_top);
1592 }
1593 
1594 #endif /* DEBUG */
1595 static void
1596 ioerror()
1597 {
1598 	longjmp(env, 1);
1599 }
1600 
1601 static void
1602 copystat(char *ifname, struct stat *ifstat, char *ofname)
1603 {
1604 	mode_t mode;
1605 	struct utimbuf timep;
1606 	acl_t *aclp = NULL;
1607 	int error;
1608 
1609 	if (fclose(outp)) {
1610 		perror(ofname);
1611 		if (!quiet) {
1612 			(void) fprintf(stderr, gettext(" -- file unchanged"));
1613 			newline_needed = 1;
1614 		}
1615 		perm_stat = 1;
1616 	} else if (ifstat == NULL) {	/* Get stat on input file */
1617 		perror(ifname);
1618 		return;
1619 	} else if ((ifstat->st_mode &
1620 			S_IFMT /* 0170000 */) != S_IFREG /* 0100000 */) {
1621 		if (quiet) {
1622 			(void) fprintf(stderr, "%s: ", ifname);
1623 		}
1624 		(void) fprintf(stderr, gettext(
1625 			" -- not a regular file: unchanged"));
1626 		newline_needed = 1;
1627 		perm_stat = 1;
1628 	} else if (ifstat->st_nlink > 1) {
1629 		if (quiet) {
1630 			(void) fprintf(stderr, "%s: ", ifname);
1631 		}
1632 		(void) fprintf(stderr, gettext(
1633 			" -- has %d other links: unchanged"),
1634 			(uint_t)ifstat->st_nlink - 1);
1635 		newline_needed = 1;
1636 		perm_stat = 1;
1637 	} else if (didnt_shrink && !force) {
1638 		/* No compression: remove file.Z */
1639 		if (!quiet) {
1640 			(void) fprintf(stderr, gettext(
1641 				" -- file unchanged"));
1642 			newline_needed = 1;
1643 		}
1644 	} else if ((pathconf(ifname, _PC_XATTR_EXISTS) == 1) &&
1645 			(mv_xattrs(ifname, ofname, 0) < 0)) {
1646 		(void) fprintf(stderr, gettext(
1647 			"%s: -- cannot preserve extended attributes, "
1648 			"file unchanged"), ifname);
1649 		newline_needed = 1;
1650 		/* Move attributes back ... */
1651 		(void) mv_xattrs(ofname, ifname, 1);
1652 		perm_stat = 1;
1653 	} else {	/* ***** Successful Compression ***** */
1654 		mode = ifstat->st_mode & 07777;
1655 		if (chmod(ofname, mode))	 /* Copy modes */
1656 			perror(ofname);
1657 
1658 		error = acl_get(ifname, ACL_NO_TRIVIAL, &aclp);
1659 		if (error != 0) {
1660 			(void) fprintf(stderr, gettext(
1661 			    "%s: failed to retrieve acl : %s\n"),
1662 			    ifname, acl_strerror(error));
1663 			perm_stat = 1;
1664 		}
1665 		if (aclp && (acl_set(ofname, aclp) < 0)) {
1666 			(void) fprintf(stderr, gettext("%s: failed to set acl "
1667 			    "entries\n"), ofname);
1668 			perm_stat = 1;
1669 		}
1670 		if (aclp) {
1671 			acl_free(aclp);
1672 			aclp = NULL;
1673 		}
1674 
1675 		/* Copy ownership */
1676 		(void) chown(ofname, ifstat->st_uid, ifstat->st_gid);
1677 		timep.actime = ifstat->st_atime;
1678 		timep.modtime = ifstat->st_mtime;
1679 		/* Update last accessed and modified times */
1680 		(void) utime(ofname, &timep);
1681 		if (unlink(ifname))	/* Remove input file */
1682 			perror(ifname);
1683 		if (!quiet) {
1684 			(void) fprintf(stderr, gettext(
1685 				" -- replaced with %s"), ofname);
1686 			newline_needed = 1;
1687 		}
1688 		return;		/* Successful return */
1689 	}
1690 
1691 	/* Unsuccessful return -- one of the tests failed */
1692 	if (ofname[0] != '\0') {
1693 		if (unlink(ofname)) {
1694 			perror(ofname);
1695 		}
1696 
1697 		ofname[0] = '\0';
1698 	}
1699 }
1700 
1701 static void
1702 onintr()
1703 {
1704 	if (!precious && !use_stdout && ofname[0] != '\0')
1705 		(void) unlink(ofname);
1706 	exit(1);
1707 }
1708 
1709 static void
1710 oops()	/* wild pointer -- assume bad input */
1711 {
1712 	if (do_decomp) {
1713 		(void) fprintf(stderr, gettext("uncompress: corrupt input\n"));
1714 	}
1715 
1716 	if (!use_stdout && ofname[0] != '\0') {
1717 		(void) unlink(ofname);
1718 	}
1719 
1720 	exit(1);
1721 }
1722 
1723 static void
1724 cl_block(count_long in_count)	/* table clear for block compress */
1725 {
1726 	count_long rat;
1727 
1728 	checkpoint = (count_long)in_count + (count_long)CHECK_GAP;
1729 #ifdef DEBUG
1730 	if (debug) {
1731 		(void) fprintf(stderr, "count: %lld, ratio: ",
1732 			(count_long)in_count);
1733 		prratio(stderr, (count_long)in_count, (count_long)bytes_out);
1734 		(void) fprintf(stderr, "\n");
1735 	}
1736 #endif /* DEBUG */
1737 
1738 	/* shift will overflow */
1739 	if ((count_long)in_count > 0x007fffffffffffffLL) {
1740 		rat = (count_long)bytes_out >> 8;
1741 		if (rat == 0) {		/* Don't divide by zero */
1742 			rat = 0x7fffffffffffffffLL;
1743 		} else {
1744 			rat = (count_long)in_count / (count_long)rat;
1745 		}
1746 	} else {
1747 		/* 8 fractional bits */
1748 		rat = ((count_long)in_count << 8) /(count_long)bytes_out;
1749 	}
1750 	if (rat > ratio) {
1751 		ratio = rat;
1752 	} else {
1753 		ratio = 0;
1754 #ifdef DEBUG
1755 		if (verbose)
1756 			dump_tab();	/* dump string table */
1757 #endif
1758 		cl_hash((count_int) hsize);
1759 		free_ent = FIRST;
1760 		clear_flg = 1;
1761 		output((code_int) CLEAR);
1762 #ifdef DEBUG
1763 		if (debug)
1764 			(void) fprintf(stderr, "clear\n");
1765 #endif /* DEBUG */
1766 	}
1767 }
1768 
1769 static void
1770 cl_hash(count_int hsize)		/* reset code table */
1771 {
1772 	count_int *htab_p = htab+hsize;
1773 	long i;
1774 	long m1 = -1;
1775 
1776 	i = hsize - 16;
1777 	do {				/* might use Sys V memset(3) here */
1778 		*(htab_p-16) = m1;
1779 		*(htab_p-15) = m1;
1780 		*(htab_p-14) = m1;
1781 		*(htab_p-13) = m1;
1782 		*(htab_p-12) = m1;
1783 		*(htab_p-11) = m1;
1784 		*(htab_p-10) = m1;
1785 		*(htab_p-9) = m1;
1786 		*(htab_p-8) = m1;
1787 		*(htab_p-7) = m1;
1788 		*(htab_p-6) = m1;
1789 		*(htab_p-5) = m1;
1790 		*(htab_p-4) = m1;
1791 		*(htab_p-3) = m1;
1792 		*(htab_p-2) = m1;
1793 		*(htab_p-1) = m1;
1794 		htab_p -= 16;
1795 	} while ((i -= 16) >= 0);
1796 		for (i += 16; i > 0; i--)
1797 			*--htab_p = m1;
1798 }
1799 
1800 static void
1801 prratio(FILE *stream, count_long num, count_long den)
1802 {
1803 	int q;  /* store percentage */
1804 
1805 	q = (int)(10000LL * (count_long)num / (count_long)den);
1806 	if (q < 0) {
1807 		(void) putc('-', stream);
1808 		q = -q;
1809 	}
1810 	(void) fprintf(stream, "%d%s%02d%%", q / 100,
1811 			localeconv()->decimal_point, q % 100);
1812 }
1813 
1814 static void
1815 version()
1816 {
1817 	(void) fprintf(stderr, "%s, Berkeley 5.9 5/11/86\n", rcs_ident);
1818 	(void) fprintf(stderr, "Options: ");
1819 #ifdef DEBUG
1820 	(void) fprintf(stderr, "DEBUG, ");
1821 #endif
1822 	(void) fprintf(stderr, "BITS = %d\n", BITS);
1823 }
1824 
1825 static void
1826 Usage()
1827 {
1828 #ifdef DEBUG
1829 	(void) fprintf(stderr,
1830 	"Usage: compress [-dDVfc] [-b maxbits] [file ...]\n");
1831 #else
1832 	if (strcmp(progname, "compress") == 0) {
1833 		(void) fprintf(stderr,
1834 		    gettext(
1835 		    "Usage: compress [-fv] [-b maxbits] [file ...]\n"\
1836 		    "       compress [-cfv] [-b maxbits] [file]\n"));
1837 	} else if (strcmp(progname, "uncompress") == 0)
1838 		(void) fprintf(stderr, gettext(
1839 		    "Usage: uncompress [-cfv] [file ...]\n"));
1840 	else if (strcmp(progname, "zcat") == 0)
1841 		(void) fprintf(stderr, gettext("Usage: zcat [file ...]\n"));
1842 
1843 #endif /* DEBUG */
1844 }
1845 
1846 static char *
1847 local_basename(char *path)
1848 {
1849 	char *p;
1850 	char *ret = (char *)path;
1851 
1852 	while ((p = (char *)strpbrk(ret, "/")) != NULL)
1853 		ret = p + 1;
1854 	return (ret);
1855 }
1856 
1857 static int
1858 addDotZ(char *fn, size_t fnsize)
1859 {
1860 	char *fn_dup;
1861 	char *dir;
1862 	long int max_name;
1863 	long int max_path;
1864 
1865 	fn_dup = strdup(fn);
1866 	dir = dirname(fn_dup);
1867 	max_name = pathconf(dir, _PC_NAME_MAX);
1868 	max_path = pathconf(dir, _PC_PATH_MAX);
1869 	free(fn_dup);
1870 
1871 	/* Check for component length too long */
1872 
1873 	if ((strlen(local_basename(fn)) + 2) > (size_t)max_name) {
1874 		(void) fprintf(stderr,
1875 			gettext("%s: filename too long to tack on .Z:"
1876 				" %s\n"), progname, fn);
1877 		return (-1);
1878 	}
1879 
1880 	/* Check for path length too long */
1881 
1882 	if ((strlen(fn) + 2) > (size_t)max_path - 1) {
1883 		(void) fprintf(stderr,
1884 			gettext("%s: Pathname too long to tack on .Z:"
1885 				" %s\n"), progname, fn);
1886 		return (-1);
1887 	}
1888 
1889 	if (strlcat(fn, ".Z", fnsize) >= fnsize) {
1890 		(void) fprintf(stderr,
1891 			gettext("%s: Buffer overflow adding .Z to %s\n"),
1892 				progname, fn);
1893 		return (-1);
1894 	}
1895 
1896 	return (0);
1897 }
1898 
1899 /*
1900  * mv_xattrs - move (via renameat) all of the extended attributes
1901  *	associated with the file infile to the file outfile.
1902  *	This function returns 0 on success and -1 on error.
1903  */
1904 static int
1905 mv_xattrs(char *infile, char *outfile, int silent)
1906 {
1907 	int indfd, outdfd, tmpfd;
1908 	DIR *dirp = NULL;
1909 	struct dirent *dp = NULL;
1910 	int error = 0;
1911 	char *etext;
1912 
1913 	indfd = outdfd = tmpfd = -1;
1914 
1915 	if ((indfd = attropen(infile, ".", O_RDONLY)) == -1) {
1916 		etext = gettext("cannot open source");
1917 		error = -1;
1918 		goto out;
1919 	}
1920 
1921 	if ((outdfd = attropen(outfile, ".", O_RDONLY)) == -1) {
1922 		etext = gettext("cannot open target");
1923 		error = -1;
1924 		goto out;
1925 	}
1926 
1927 	if ((tmpfd = dup(indfd)) == -1) {
1928 		etext = gettext("cannot dup descriptor");
1929 		error = -1;
1930 		goto out;
1931 
1932 	}
1933 	if ((dirp = fdopendir(tmpfd)) == NULL) {
1934 		etext = gettext("cannot access source");
1935 		error = -1;
1936 		goto out;
1937 	}
1938 
1939 	while (dp = readdir(dirp)) {
1940 		if ((dp->d_name[0] == '.' && dp->d_name[1] == '\0') ||
1941 		    (dp->d_name[0] == '.' && dp->d_name[1] == '.' &&
1942 		    dp->d_name[2] == '\0'))
1943 			continue;
1944 		if ((renameat(indfd, dp->d_name, outdfd, dp->d_name)) == -1) {
1945 			etext = dp->d_name;
1946 			error = -1;
1947 			goto out;
1948 		}
1949 	}
1950 out:
1951 	if (error == -1 && silent == 0) {
1952 		if (quiet) {
1953 			(void) fprintf(stderr, "%s: ", infile);
1954 		} else {
1955 			(void) fprintf(stderr, ", ");
1956 		}
1957 		(void) fprintf(stderr, gettext("extended attribute error: "));
1958 		perror(etext);
1959 	}
1960 	if (dirp)
1961 		(void) closedir(dirp);
1962 	if (indfd != -1)
1963 		(void) close(indfd);
1964 	if (outdfd != -1)
1965 		(void) close(outdfd);
1966 	return (error);
1967 }
1968