col.c revision 11765 
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#include <locale.h>
53
54#define	BS	'\b'		/* backspace */
55#define	TAB	'\t'		/* tab */
56#define	SPACE	' '		/* space */
57#define	NL	'\n'		/* newline */
58#define	CR	'\r'		/* carriage return */
59#define	ESC	'\033'		/* escape */
60#define	SI	'\017'		/* shift in to normal character set */
61#define	SO	'\016'		/* shift out to alternate character set */
62#define	VT	'\013'		/* vertical tab (aka reverse line feed) */
63#define	RLF	'\007'		/* ESC-07 reverse line feed */
64#define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
65#define	FHLF	'\011'		/* ESC-011 forward half-line feed */
66
67/* build up at least this many lines before flushing them out */
68#define	BUFFER_MARGIN		32
69
70typedef char CSET;
71
72typedef struct char_str {
73#define	CS_NORMAL	1
74#define	CS_ALTERNATE	2
75	short		c_column;	/* column character is in */
76	CSET		c_set;		/* character set (currently only 2) */
77	char		c_char;		/* character in question */
78} CHAR;
79
80typedef struct line_str LINE;
81struct line_str {
82	CHAR	*l_line;		/* characters on the line */
83	LINE	*l_prev;		/* previous line */
84	LINE	*l_next;		/* next line */
85	int	l_lsize;		/* allocated sizeof l_line */
86	int	l_line_len;		/* strlen(l_line) */
87	int	l_needs_sort;		/* set if chars went in out of order */
88	int	l_max_col;		/* max column in the line */
89};
90
91LINE   *alloc_line __P((void));
92void	dowarn __P((int));
93void	flush_line __P((LINE *));
94void	flush_lines __P((int));
95void	flush_blanks __P((void));
96void	free_line __P((LINE *));
97void	usage __P((void));
98void	wrerr __P((void));
99void   *xmalloc __P((void *, size_t));
100
101CSET	last_set;		/* char_set of last char printed */
102LINE   *lines;
103int	compress_spaces;	/* if doing space -> tab conversion */
104int	fine;			/* if `fine' resolution (half lines) */
105int	max_bufd_lines;		/* max # lines to keep in memory */
106int	nblank_lines;		/* # blanks after last flushed line */
107int	no_backspaces;		/* if not to output any backspaces */
108
109#define	PUTC(ch) \
110	do {				\
111		if (putchar(ch) == EOF) \
112			wrerr();	\
113	} while (0)
114
115int
116main(argc, argv)
117	int argc;
118	char **argv;
119{
120	int ch;
121	CHAR *c;
122	CSET cur_set;			/* current character set */
123	LINE *l;			/* current line */
124	int extra_lines;		/* # of lines above first line */
125	int cur_col;			/* current column */
126	int cur_line;			/* line number of current position */
127	int max_line;			/* max value of cur_line */
128	int this_line;			/* line l points to */
129	int nflushd_lines;		/* number of lines that were flushed */
130	int adjust, opt, warned;
131
132	(void) setlocale(LC_CTYPE, "");
133
134	max_bufd_lines = 128;
135	compress_spaces = 1;		/* compress spaces into tabs */
136	while ((opt = getopt(argc, argv, "bfhl:x")) != EOF)
137		switch (opt) {
138		case 'b':		/* do not output backspaces */
139			no_backspaces = 1;
140			break;
141		case 'f':		/* allow half forward line feeds */
142			fine = 1;
143			break;
144		case 'h':		/* compress spaces into tabs */
145			compress_spaces = 1;
146			break;
147		case 'l':		/* buffered line count */
148			if ((max_bufd_lines = atoi(optarg)) <= 0) {
149				(void)fprintf(stderr,
150				    "col: bad -l argument %s.\n", optarg);
151				exit(1);
152			}
153			break;
154		case 'x':		/* do not compress spaces into tabs */
155			compress_spaces = 0;
156			break;
157		case '?':
158		default:
159			usage();
160		}
161
162	if (optind != argc)
163		usage();
164
165	/* this value is in half lines */
166	max_bufd_lines *= 2;
167
168	adjust = cur_col = extra_lines = warned = 0;
169	cur_line = max_line = nflushd_lines = this_line = 0;
170	cur_set = last_set = CS_NORMAL;
171	lines = l = alloc_line();
172
173	while ((ch = getchar()) != EOF) {
174		if (!isgraph(ch)) {
175			switch (ch) {
176			case BS:		/* can't go back further */
177				if (cur_col == 0)
178					continue;
179				--cur_col;
180				continue;
181			case CR:
182				cur_col = 0;
183				continue;
184			case ESC:		/* just ignore EOF */
185				switch(getchar()) {
186				case RLF:
187					cur_line -= 2;
188					break;
189				case RHLF:
190					cur_line--;
191					break;
192				case FHLF:
193					cur_line++;
194					if (cur_line > max_line)
195						max_line = cur_line;
196				}
197				continue;
198			case NL:
199				cur_line += 2;
200				if (cur_line > max_line)
201					max_line = cur_line;
202				cur_col = 0;
203				continue;
204			case SPACE:
205				++cur_col;
206				continue;
207			case SI:
208				cur_set = CS_NORMAL;
209				continue;
210			case SO:
211				cur_set = CS_ALTERNATE;
212				continue;
213			case TAB:		/* adjust column */
214				cur_col |= 7;
215				++cur_col;
216				continue;
217			case VT:
218				cur_line -= 2;
219				continue;
220			}
221			continue;
222		}
223
224		/* Must stuff ch in a line - are we at the right one? */
225		if (cur_line != this_line - adjust) {
226			LINE *lnew;
227			int nmove;
228
229			adjust = 0;
230			nmove = cur_line - this_line;
231			if (!fine) {
232				/* round up to next line */
233				if (cur_line & 1) {
234					adjust = 1;
235					nmove++;
236				}
237			}
238			if (nmove < 0) {
239				for (; nmove < 0 && l->l_prev; nmove++)
240					l = l->l_prev;
241				if (nmove) {
242					if (nflushd_lines == 0) {
243						/*
244						 * Allow backup past first
245						 * line if nothing has been
246						 * flushed yet.
247						 */
248						for (; nmove < 0; nmove++) {
249							lnew = alloc_line();
250							l->l_prev = lnew;
251							lnew->l_next = l;
252							l = lines = lnew;
253							extra_lines++;
254						}
255					} else {
256						if (!warned++)
257							dowarn(cur_line);
258						cur_line -= nmove;
259					}
260				}
261			} else {
262				/* may need to allocate here */
263				for (; nmove > 0 && l->l_next; nmove--)
264					l = l->l_next;
265				for (; nmove > 0; nmove--) {
266					lnew = alloc_line();
267					lnew->l_prev = l;
268					l->l_next = lnew;
269					l = lnew;
270				}
271			}
272			this_line = cur_line + adjust;
273			nmove = this_line - nflushd_lines;
274			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
275				nflushd_lines += nmove - max_bufd_lines;
276				flush_lines(nmove - max_bufd_lines);
277			}
278		}
279		/* grow line's buffer? */
280		if (l->l_line_len + 1 >= l->l_lsize) {
281			int need;
282
283			need = l->l_lsize ? l->l_lsize * 2 : 90;
284			l->l_line = (CHAR *)xmalloc((void *) l->l_line,
285			    (unsigned) need * sizeof(CHAR));
286			l->l_lsize = need;
287		}
288		c = &l->l_line[l->l_line_len++];
289		c->c_char = ch;
290		c->c_set = cur_set;
291		c->c_column = cur_col;
292		/*
293		 * If things are put in out of order, they will need sorting
294		 * when it is flushed.
295		 */
296		if (cur_col < l->l_max_col)
297			l->l_needs_sort = 1;
298		else
299			l->l_max_col = cur_col;
300		cur_col++;
301	}
302	/* goto the last line that had a character on it */
303	for (; l->l_next; l = l->l_next)
304		this_line++;
305	flush_lines(this_line - nflushd_lines + extra_lines + 1);
306
307	/* make sure we leave things in a sane state */
308	if (last_set != CS_NORMAL)
309		PUTC('\017');
310
311	/* flush out the last few blank lines */
312	nblank_lines = max_line - this_line;
313	if (max_line & 1)
314		nblank_lines++;
315	else if (!nblank_lines)
316		/* missing a \n on the last line? */
317		nblank_lines = 2;
318	flush_blanks();
319	exit(0);
320}
321
322void
323flush_lines(nflush)
324	int nflush;
325{
326	LINE *l;
327
328	while (--nflush >= 0) {
329		l = lines;
330		lines = l->l_next;
331		if (l->l_line) {
332			flush_blanks();
333			flush_line(l);
334		}
335		nblank_lines++;
336		if (l->l_line)
337			(void)free((void *)l->l_line);
338		free_line(l);
339	}
340	if (lines)
341		lines->l_prev = NULL;
342}
343
344/*
345 * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
346 * is the number of half line feeds, otherwise it is the number of whole line
347 * feeds.
348 */
349void
350flush_blanks()
351{
352	int half, i, nb;
353
354	half = 0;
355	nb = nblank_lines;
356	if (nb & 1) {
357		if (fine)
358			half = 1;
359		else
360			nb++;
361	}
362	nb /= 2;
363	for (i = nb; --i >= 0;)
364		PUTC('\n');
365	if (half) {
366		PUTC('\033');
367		PUTC('9');
368		if (!nb)
369			PUTC('\r');
370	}
371	nblank_lines = 0;
372}
373
374/*
375 * Write a line to stdout taking care of space to tab conversion (-h flag)
376 * and character set shifts.
377 */
378void
379flush_line(l)
380	LINE *l;
381{
382	CHAR *c, *endc;
383	int nchars, last_col, this_col;
384
385	last_col = 0;
386	nchars = l->l_line_len;
387
388	if (l->l_needs_sort) {
389		static CHAR *sorted;
390		static int count_size, *count, i, save, sorted_size, tot;
391
392		/*
393		 * Do an O(n) sort on l->l_line by column being careful to
394		 * preserve the order of characters in the same column.
395		 */
396		if (l->l_lsize > sorted_size) {
397			sorted_size = l->l_lsize;
398			sorted = (CHAR *)xmalloc((void *)sorted,
399			    (unsigned)sizeof(CHAR) * sorted_size);
400		}
401		if (l->l_max_col >= count_size) {
402			count_size = l->l_max_col + 1;
403			count = (int *)xmalloc((void *)count,
404			    (unsigned)sizeof(int) * count_size);
405		}
406		memset((char *)count, 0, sizeof(int) * l->l_max_col + 1);
407		for (i = nchars, c = l->l_line; --i >= 0; c++)
408			count[c->c_column]++;
409
410		/*
411		 * calculate running total (shifted down by 1) to use as
412		 * indices into new line.
413		 */
414		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
415			save = count[i];
416			count[i] = tot;
417			tot += save;
418		}
419
420		for (i = nchars, c = l->l_line; --i >= 0; c++)
421			sorted[count[c->c_column]++] = *c;
422		c = sorted;
423	} else
424		c = l->l_line;
425	while (nchars > 0) {
426		this_col = c->c_column;
427		endc = c;
428		do {
429			++endc;
430		} while (--nchars > 0 && this_col == endc->c_column);
431
432		/* if -b only print last character */
433		if (no_backspaces)
434			c = endc - 1;
435
436		if (this_col > last_col) {
437			int nspace = this_col - last_col;
438
439			if (compress_spaces && nspace > 1) {
440				while (1) {
441					int tab_col, tab_size;;
442
443					tab_col = (last_col + 8) & ~7;
444					if (tab_col > this_col)
445						break;
446					tab_size = tab_col - last_col;
447					if (tab_size == 1)
448						PUTC(' ');
449					else
450						PUTC('\t');
451					nspace -= tab_size;
452					last_col = tab_col;
453				}
454			}
455			while (--nspace >= 0)
456				PUTC(' ');
457			last_col = this_col;
458		}
459		last_col++;
460
461		for (;;) {
462			if (c->c_set != last_set) {
463				switch (c->c_set) {
464				case CS_NORMAL:
465					PUTC('\017');
466					break;
467				case CS_ALTERNATE:
468					PUTC('\016');
469				}
470				last_set = c->c_set;
471			}
472			PUTC(c->c_char);
473			if (++c >= endc)
474				break;
475			PUTC('\b');
476		}
477	}
478}
479
480#define	NALLOC 64
481
482static LINE *line_freelist;
483
484LINE *
485alloc_line()
486{
487	LINE *l;
488	int i;
489
490	if (!line_freelist) {
491		l = (LINE *)xmalloc((void *)NULL, sizeof(LINE) * NALLOC);
492		line_freelist = l;
493		for (i = 1; i < NALLOC; i++, l++)
494			l->l_next = l + 1;
495		l->l_next = NULL;
496	}
497	l = line_freelist;
498	line_freelist = l->l_next;
499
500	memset(l, 0, sizeof(LINE));
501	return (l);
502}
503
504void
505free_line(l)
506	LINE *l;
507{
508
509	l->l_next = line_freelist;
510	line_freelist = l;
511}
512
513void *
514xmalloc(p, size)
515	void *p;
516	size_t size;
517{
518
519	if (!(p = (void *)realloc(p, size)))
520		err(1, NULL);
521	return (p);
522}
523
524void
525usage()
526{
527
528	(void)fprintf(stderr, "usage: col [-bfx] [-l nline]\n");
529	exit(1);
530}
531
532void
533wrerr()
534{
535
536	(void)fprintf(stderr, "col: write error.\n");
537	exit(1);
538}
539
540void
541dowarn(line)
542	int line;
543{
544
545	warnx("warning: can't back up %s",
546		line < 0 ? "past first line" : "-- line already flushed");
547}
548