col.c revision 1590 
1/*-
2 * Copyright (c) 1990, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Michael Rendell of the Memorial University of Newfoundland.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#ifndef lint
38static char copyright[] =
39"@(#) Copyright (c) 1990, 1993, 1994\n\
40	The Regents of the University of California.  All rights reserved.\n";
41#endif /* not lint */
42
43#ifndef lint
44static char sccsid[] = "@(#)col.c	8.3 (Berkeley) 4/2/94";
45#endif /* not lint */
46
47#include <ctype.h>
48#include <err.h>
49#include <string.h>
50#include <stdio.h>
51#include <stdlib.h>
52
53#define	BS	'\b'		/* backspace */
54#define	TAB	'\t'		/* tab */
55#define	SPACE	' '		/* space */
56#define	NL	'\n'		/* newline */
57#define	CR	'\r'		/* carriage return */
58#define	ESC	'\033'		/* escape */
59#define	SI	'\017'		/* shift in to normal character set */
60#define	SO	'\016'		/* shift out to alternate character set */
61#define	VT	'\013'		/* vertical tab (aka reverse line feed) */
62#define	RLF	'\007'		/* ESC-07 reverse line feed */
63#define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
64#define	FHLF	'\011'		/* ESC-011 forward half-line feed */
65
66/* build up at least this many lines before flushing them out */
67#define	BUFFER_MARGIN		32
68
69typedef char CSET;
70
71typedef struct char_str {
72#define	CS_NORMAL	1
73#define	CS_ALTERNATE	2
74	short		c_column;	/* column character is in */
75	CSET		c_set;		/* character set (currently only 2) */
76	char		c_char;		/* character in question */
77} CHAR;
78
79typedef struct line_str LINE;
80struct line_str {
81	CHAR	*l_line;		/* characters on the line */
82	LINE	*l_prev;		/* previous line */
83	LINE	*l_next;		/* next line */
84	int	l_lsize;		/* allocated sizeof l_line */
85	int	l_line_len;		/* strlen(l_line) */
86	int	l_needs_sort;		/* set if chars went in out of order */
87	int	l_max_col;		/* max column in the line */
88};
89
90LINE   *alloc_line __P((void));
91void	dowarn __P((int));
92void	flush_line __P((LINE *));
93void	flush_lines __P((int));
94void	flush_blanks __P((void));
95void	free_line __P((LINE *));
96void	usage __P((void));
97void	wrerr __P((void));
98void   *xmalloc __P((void *, size_t));
99
100CSET	last_set;		/* char_set of last char printed */
101LINE   *lines;
102int	compress_spaces;	/* if doing space -> tab conversion */
103int	fine;			/* if `fine' resolution (half lines) */
104int	max_bufd_lines;		/* max # lines to keep in memory */
105int	nblank_lines;		/* # blanks after last flushed line */
106int	no_backspaces;		/* if not to output any backspaces */
107
108#define	PUTC(ch) \
109	if (putchar(ch) == EOF) \
110		wrerr();
111
112int
113main(argc, argv)
114	int argc;
115	char **argv;
116{
117	int ch;
118	CHAR *c;
119	CSET cur_set;			/* current character set */
120	LINE *l;			/* current line */
121	int extra_lines;		/* # of lines above first line */
122	int cur_col;			/* current column */
123	int cur_line;			/* line number of current position */
124	int max_line;			/* max value of cur_line */
125	int this_line;			/* line l points to */
126	int nflushd_lines;		/* number of lines that were flushed */
127	int adjust, opt, warned;
128
129	max_bufd_lines = 128;
130	compress_spaces = 1;		/* compress spaces into tabs */
131	while ((opt = getopt(argc, argv, "bfhl:x")) != EOF)
132		switch (opt) {
133		case 'b':		/* do not output backspaces */
134			no_backspaces = 1;
135			break;
136		case 'f':		/* allow half forward line feeds */
137			fine = 1;
138			break;
139		case 'h':		/* compress spaces into tabs */
140			compress_spaces = 1;
141			break;
142		case 'l':		/* buffered line count */
143			if ((max_bufd_lines = atoi(optarg)) <= 0) {
144				(void)fprintf(stderr,
145				    "col: bad -l argument %s.\n", optarg);
146				exit(1);
147			}
148			break;
149		case 'x':		/* do not compress spaces into tabs */
150			compress_spaces = 0;
151			break;
152		case '?':
153		default:
154			usage();
155		}
156
157	if (optind != argc)
158		usage();
159
160	/* this value is in half lines */
161	max_bufd_lines *= 2;
162
163	adjust = cur_col = extra_lines = warned = 0;
164	cur_line = max_line = nflushd_lines = this_line = 0;
165	cur_set = last_set = CS_NORMAL;
166	lines = l = alloc_line();
167
168	while ((ch = getchar()) != EOF) {
169		if (!isgraph(ch)) {
170			switch (ch) {
171			case BS:		/* can't go back further */
172				if (cur_col == 0)
173					continue;
174				--cur_col;
175				continue;
176			case CR:
177				cur_col = 0;
178				continue;
179			case ESC:		/* just ignore EOF */
180				switch(getchar()) {
181				case RLF:
182					cur_line -= 2;
183					break;
184				case RHLF:
185					cur_line--;
186					break;
187				case FHLF:
188					cur_line++;
189					if (cur_line > max_line)
190						max_line = cur_line;
191				}
192				continue;
193			case NL:
194				cur_line += 2;
195				if (cur_line > max_line)
196					max_line = cur_line;
197				cur_col = 0;
198				continue;
199			case SPACE:
200				++cur_col;
201				continue;
202			case SI:
203				cur_set = CS_NORMAL;
204				continue;
205			case SO:
206				cur_set = CS_ALTERNATE;
207				continue;
208			case TAB:		/* adjust column */
209				cur_col |= 7;
210				++cur_col;
211				continue;
212			case VT:
213				cur_line -= 2;
214				continue;
215			}
216			continue;
217		}
218
219		/* Must stuff ch in a line - are we at the right one? */
220		if (cur_line != this_line - adjust) {
221			LINE *lnew;
222			int nmove;
223
224			adjust = 0;
225			nmove = cur_line - this_line;
226			if (!fine) {
227				/* round up to next line */
228				if (cur_line & 1) {
229					adjust = 1;
230					nmove++;
231				}
232			}
233			if (nmove < 0) {
234				for (; nmove < 0 && l->l_prev; nmove++)
235					l = l->l_prev;
236				if (nmove) {
237					if (nflushd_lines == 0) {
238						/*
239						 * Allow backup past first
240						 * line if nothing has been
241						 * flushed yet.
242						 */
243						for (; nmove < 0; nmove++) {
244							lnew = alloc_line();
245							l->l_prev = lnew;
246							lnew->l_next = l;
247							l = lines = lnew;
248							extra_lines++;
249						}
250					} else {
251						if (!warned++)
252							dowarn(cur_line);
253						cur_line -= nmove;
254					}
255				}
256			} else {
257				/* may need to allocate here */
258				for (; nmove > 0 && l->l_next; nmove--)
259					l = l->l_next;
260				for (; nmove > 0; nmove--) {
261					lnew = alloc_line();
262					lnew->l_prev = l;
263					l->l_next = lnew;
264					l = lnew;
265				}
266			}
267			this_line = cur_line + adjust;
268			nmove = this_line - nflushd_lines;
269			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
270				nflushd_lines += nmove - max_bufd_lines;
271				flush_lines(nmove - max_bufd_lines);
272			}
273		}
274		/* grow line's buffer? */
275		if (l->l_line_len + 1 >= l->l_lsize) {
276			int need;
277
278			need = l->l_lsize ? l->l_lsize * 2 : 90;
279			l->l_line = (CHAR *)xmalloc((void *) l->l_line,
280			    (unsigned) need * sizeof(CHAR));
281			l->l_lsize = need;
282		}
283		c = &l->l_line[l->l_line_len++];
284		c->c_char = ch;
285		c->c_set = cur_set;
286		c->c_column = cur_col;
287		/*
288		 * If things are put in out of order, they will need sorting
289		 * when it is flushed.
290		 */
291		if (cur_col < l->l_max_col)
292			l->l_needs_sort = 1;
293		else
294			l->l_max_col = cur_col;
295		cur_col++;
296	}
297	/* goto the last line that had a character on it */
298	for (; l->l_next; l = l->l_next)
299		this_line++;
300	flush_lines(this_line - nflushd_lines + extra_lines + 1);
301
302	/* make sure we leave things in a sane state */
303	if (last_set != CS_NORMAL)
304		PUTC('\017');
305
306	/* flush out the last few blank lines */
307	nblank_lines = max_line - this_line;
308	if (max_line & 1)
309		nblank_lines++;
310	else if (!nblank_lines)
311		/* missing a \n on the last line? */
312		nblank_lines = 2;
313	flush_blanks();
314	exit(0);
315}
316
317void
318flush_lines(nflush)
319	int nflush;
320{
321	LINE *l;
322
323	while (--nflush >= 0) {
324		l = lines;
325		lines = l->l_next;
326		if (l->l_line) {
327			flush_blanks();
328			flush_line(l);
329		}
330		nblank_lines++;
331		if (l->l_line)
332			(void)free((void *)l->l_line);
333		free_line(l);
334	}
335	if (lines)
336		lines->l_prev = NULL;
337}
338
339/*
340 * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
341 * is the number of half line feeds, otherwise it is the number of whole line
342 * feeds.
343 */
344void
345flush_blanks()
346{
347	int half, i, nb;
348
349	half = 0;
350	nb = nblank_lines;
351	if (nb & 1) {
352		if (fine)
353			half = 1;
354		else
355			nb++;
356	}
357	nb /= 2;
358	for (i = nb; --i >= 0;)
359		PUTC('\n');
360	if (half) {
361		PUTC('\033');
362		PUTC('9');
363		if (!nb)
364			PUTC('\r');
365	}
366	nblank_lines = 0;
367}
368
369/*
370 * Write a line to stdout taking care of space to tab conversion (-h flag)
371 * and character set shifts.
372 */
373void
374flush_line(l)
375	LINE *l;
376{
377	CHAR *c, *endc;
378	int nchars, last_col, this_col;
379
380	last_col = 0;
381	nchars = l->l_line_len;
382
383	if (l->l_needs_sort) {
384		static CHAR *sorted;
385		static int count_size, *count, i, save, sorted_size, tot;
386
387		/*
388		 * Do an O(n) sort on l->l_line by column being careful to
389		 * preserve the order of characters in the same column.
390		 */
391		if (l->l_lsize > sorted_size) {
392			sorted_size = l->l_lsize;
393			sorted = (CHAR *)xmalloc((void *)sorted,
394			    (unsigned)sizeof(CHAR) * sorted_size);
395		}
396		if (l->l_max_col >= count_size) {
397			count_size = l->l_max_col + 1;
398			count = (int *)xmalloc((void *)count,
399			    (unsigned)sizeof(int) * count_size);
400		}
401		memset((char *)count, 0, sizeof(int) * l->l_max_col + 1);
402		for (i = nchars, c = l->l_line; --i >= 0; c++)
403			count[c->c_column]++;
404
405		/*
406		 * calculate running total (shifted down by 1) to use as
407		 * indices into new line.
408		 */
409		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
410			save = count[i];
411			count[i] = tot;
412			tot += save;
413		}
414
415		for (i = nchars, c = l->l_line; --i >= 0; c++)
416			sorted[count[c->c_column]++] = *c;
417		c = sorted;
418	} else
419		c = l->l_line;
420	while (nchars > 0) {
421		this_col = c->c_column;
422		endc = c;
423		do {
424			++endc;
425		} while (--nchars > 0 && this_col == endc->c_column);
426
427		/* if -b only print last character */
428		if (no_backspaces)
429			c = endc - 1;
430
431		if (this_col > last_col) {
432			int nspace = this_col - last_col;
433
434			if (compress_spaces && nspace > 1) {
435				int ntabs;
436
437				ntabs = this_col / 8 - last_col / 8;
438				nspace -= ntabs * 8;
439				while (--ntabs >= 0)
440					PUTC('\t');
441			}
442			while (--nspace >= 0)
443				PUTC(' ');
444			last_col = this_col;
445		}
446		last_col++;
447
448		for (;;) {
449			if (c->c_set != last_set) {
450				switch (c->c_set) {
451				case CS_NORMAL:
452					PUTC('\017');
453					break;
454				case CS_ALTERNATE:
455					PUTC('\016');
456				}
457				last_set = c->c_set;
458			}
459			PUTC(c->c_char);
460			if (++c >= endc)
461				break;
462			PUTC('\b');
463		}
464	}
465}
466
467#define	NALLOC 64
468
469static LINE *line_freelist;
470
471LINE *
472alloc_line()
473{
474	LINE *l;
475	int i;
476
477	if (!line_freelist) {
478		l = (LINE *)xmalloc((void *)NULL, sizeof(LINE) * NALLOC);
479		line_freelist = l;
480		for (i = 1; i < NALLOC; i++, l++)
481			l->l_next = l + 1;
482		l->l_next = NULL;
483	}
484	l = line_freelist;
485	line_freelist = l->l_next;
486
487	memset(l, 0, sizeof(LINE));
488	return (l);
489}
490
491void
492free_line(l)
493	LINE *l;
494{
495
496	l->l_next = line_freelist;
497	line_freelist = l;
498}
499
500void *
501xmalloc(p, size)
502	void *p;
503	size_t size;
504{
505
506	if (!(p = (void *)realloc(p, size)))
507		err(1, NULL);
508	return (p);
509}
510
511void
512usage()
513{
514
515	(void)fprintf(stderr, "usage: col [-bfx] [-l nline]\n");
516	exit(1);
517}
518
519void
520wrerr()
521{
522
523	(void)fprintf(stderr, "col: write error.\n");
524	exit(1);
525}
526
527void
528dowarn(line)
529	int line;
530{
531
532	warnx("warning: can't back up %s",
533		line < 0 ? "past first line" : "-- line already flushed");
534}
535