col.c revision 132824 
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 const char copyright[] =
39"@(#) Copyright (c) 1990, 1993, 1994\n\
40	The Regents of the University of California.  All rights reserved.\n";
41#endif
42
43#if 0
44#ifndef lint
45static char sccsid[] = "@(#)col.c	8.5 (Berkeley) 5/4/95";
46#endif
47#endif
48
49#include <sys/cdefs.h>
50__FBSDID("$FreeBSD: head/usr.bin/col/col.c 132824 2004-07-29 07:23:37Z tjr $");
51
52#include <err.h>
53#include <locale.h>
54#include <string.h>
55#include <stdio.h>
56#include <stdlib.h>
57#include <unistd.h>
58#include <locale.h>
59#include <wchar.h>
60#include <wctype.h>
61
62#define	BS	'\b'		/* backspace */
63#define	TAB	'\t'		/* tab */
64#define	SPACE	' '		/* space */
65#define	NL	'\n'		/* newline */
66#define	CR	'\r'		/* carriage return */
67#define	ESC	'\033'		/* escape */
68#define	SI	'\017'		/* shift in to normal character set */
69#define	SO	'\016'		/* shift out to alternate character set */
70#define	VT	'\013'		/* vertical tab (aka reverse line feed) */
71#define	RLF	'\007'		/* ESC-07 reverse line feed */
72#define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
73#define	FHLF	'\011'		/* ESC-011 forward half-line feed */
74
75/* build up at least this many lines before flushing them out */
76#define	BUFFER_MARGIN		32
77
78typedef char CSET;
79
80typedef struct char_str {
81#define	CS_NORMAL	1
82#define	CS_ALTERNATE	2
83	short		c_column;	/* column character is in */
84	CSET		c_set;		/* character set (currently only 2) */
85	wchar_t		c_char;		/* character in question */
86	int		c_width;	/* character width */
87} CHAR;
88
89typedef struct line_str LINE;
90struct line_str {
91	CHAR	*l_line;		/* characters on the line */
92	LINE	*l_prev;		/* previous line */
93	LINE	*l_next;		/* next line */
94	int	l_lsize;		/* allocated sizeof l_line */
95	int	l_line_len;		/* strlen(l_line) */
96	int	l_needs_sort;		/* set if chars went in out of order */
97	int	l_max_col;		/* max column in the line */
98};
99
100LINE   *alloc_line(void);
101void	dowarn(int);
102void	flush_line(LINE *);
103void	flush_lines(int);
104void	flush_blanks(void);
105void	free_line(LINE *);
106void	usage(void);
107
108CSET	last_set;		/* char_set of last char printed */
109LINE   *lines;
110int	compress_spaces;	/* if doing space -> tab conversion */
111int	fine;			/* if `fine' resolution (half lines) */
112int	max_bufd_lines;		/* max # lines to keep in memory */
113int	nblank_lines;		/* # blanks after last flushed line */
114int	no_backspaces;		/* if not to output any backspaces */
115int	pass_unknown_seqs;	/* pass unknown control sequences */
116
117#define	PUTC(ch) \
118	do {					\
119		if (putwchar(ch) == WEOF)	\
120			errx(1, "write error");	\
121	} while (0)
122
123int
124main(int argc, char **argv)
125{
126	wint_t ch;
127	CHAR *c;
128	CSET cur_set;			/* current character set */
129	LINE *l;			/* current line */
130	int extra_lines;		/* # of lines above first line */
131	int cur_col;			/* current column */
132	int cur_line;			/* line number of current position */
133	int max_line;			/* max value of cur_line */
134	int this_line;			/* line l points to */
135	int nflushd_lines;		/* number of lines that were flushed */
136	int adjust, opt, warned, width;
137
138	(void)setlocale(LC_CTYPE, "");
139
140	max_bufd_lines = 128;
141	compress_spaces = 1;		/* compress spaces into tabs */
142	while ((opt = getopt(argc, argv, "bfhl:px")) != -1)
143		switch (opt) {
144		case 'b':		/* do not output backspaces */
145			no_backspaces = 1;
146			break;
147		case 'f':		/* allow half forward line feeds */
148			fine = 1;
149			break;
150		case 'h':		/* compress spaces into tabs */
151			compress_spaces = 1;
152			break;
153		case 'l':		/* buffered line count */
154			if ((max_bufd_lines = atoi(optarg)) <= 0)
155				errx(1, "bad -l argument %s", optarg);
156			break;
157		case 'p':		/* pass unknown control sequences */
158			pass_unknown_seqs = 1;
159			break;
160		case 'x':		/* do not compress spaces into tabs */
161			compress_spaces = 0;
162			break;
163		case '?':
164		default:
165			usage();
166		}
167
168	if (optind != argc)
169		usage();
170
171	/* this value is in half lines */
172	max_bufd_lines *= 2;
173
174	adjust = cur_col = extra_lines = warned = 0;
175	cur_line = max_line = nflushd_lines = this_line = 0;
176	cur_set = last_set = CS_NORMAL;
177	lines = l = alloc_line();
178
179	while ((ch = getwchar()) != WEOF) {
180		if (!iswgraph(ch)) {
181			switch (ch) {
182			case BS:		/* can't go back further */
183				if (cur_col == 0)
184					continue;
185				--cur_col;
186				continue;
187			case CR:
188				cur_col = 0;
189				continue;
190			case ESC:		/* just ignore EOF */
191				switch(getwchar()) {
192				case RLF:
193					cur_line -= 2;
194					break;
195				case RHLF:
196					cur_line--;
197					break;
198				case FHLF:
199					cur_line++;
200					if (cur_line > max_line)
201						max_line = cur_line;
202				}
203				continue;
204			case NL:
205				cur_line += 2;
206				if (cur_line > max_line)
207					max_line = cur_line;
208				cur_col = 0;
209				continue;
210			case SPACE:
211				++cur_col;
212				continue;
213			case SI:
214				cur_set = CS_NORMAL;
215				continue;
216			case SO:
217				cur_set = CS_ALTERNATE;
218				continue;
219			case TAB:		/* adjust column */
220				cur_col |= 7;
221				++cur_col;
222				continue;
223			case VT:
224				cur_line -= 2;
225				continue;
226			}
227			if (iswspace(ch)) {
228				if ((width = wcwidth(ch)) > 0)
229					cur_col += width;
230				continue;
231			}
232			if (!pass_unknown_seqs)
233				continue;
234		}
235
236		/* Must stuff ch in a line - are we at the right one? */
237		if (cur_line != this_line - adjust) {
238			LINE *lnew;
239			int nmove;
240
241			adjust = 0;
242			nmove = cur_line - this_line;
243			if (!fine) {
244				/* round up to next line */
245				if (cur_line & 1) {
246					adjust = 1;
247					nmove++;
248				}
249			}
250			if (nmove < 0) {
251				for (; nmove < 0 && l->l_prev; nmove++)
252					l = l->l_prev;
253				if (nmove) {
254					if (nflushd_lines == 0) {
255						/*
256						 * Allow backup past first
257						 * line if nothing has been
258						 * flushed yet.
259						 */
260						for (; nmove < 0; nmove++) {
261							lnew = alloc_line();
262							l->l_prev = lnew;
263							lnew->l_next = l;
264							l = lines = lnew;
265							extra_lines++;
266						}
267					} else {
268						if (!warned++)
269							dowarn(cur_line);
270						cur_line -= nmove;
271					}
272				}
273			} else {
274				/* may need to allocate here */
275				for (; nmove > 0 && l->l_next; nmove--)
276					l = l->l_next;
277				for (; nmove > 0; nmove--) {
278					lnew = alloc_line();
279					lnew->l_prev = l;
280					l->l_next = lnew;
281					l = lnew;
282				}
283			}
284			this_line = cur_line + adjust;
285			nmove = this_line - nflushd_lines;
286			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
287				nflushd_lines += nmove - max_bufd_lines;
288				flush_lines(nmove - max_bufd_lines);
289			}
290		}
291		/* grow line's buffer? */
292		if (l->l_line_len + 1 >= l->l_lsize) {
293			int need;
294
295			need = l->l_lsize ? l->l_lsize * 2 : 90;
296			if ((l->l_line = realloc(l->l_line,
297			    (unsigned)need * sizeof(CHAR))) == NULL)
298				err(1, (char *)NULL);
299			l->l_lsize = need;
300		}
301		c = &l->l_line[l->l_line_len++];
302		c->c_char = ch;
303		c->c_set = cur_set;
304		c->c_column = cur_col;
305		c->c_width = wcwidth(ch);
306		/*
307		 * If things are put in out of order, they will need sorting
308		 * when it is flushed.
309		 */
310		if (cur_col < l->l_max_col)
311			l->l_needs_sort = 1;
312		else
313			l->l_max_col = cur_col;
314		if (c->c_width > 0)
315			cur_col += c->c_width;
316	}
317	if (ferror(stdin))
318		err(1, NULL);
319	if (max_line == 0)
320		exit(0);	/* no lines, so just exit */
321
322	/* goto the last line that had a character on it */
323	for (; l->l_next; l = l->l_next)
324		this_line++;
325	flush_lines(this_line - nflushd_lines + extra_lines + 1);
326
327	/* make sure we leave things in a sane state */
328	if (last_set != CS_NORMAL)
329		PUTC('\017');
330
331	/* flush out the last few blank lines */
332	nblank_lines = max_line - this_line;
333	if (max_line & 1)
334		nblank_lines++;
335	else if (!nblank_lines)
336		/* missing a \n on the last line? */
337		nblank_lines = 2;
338	flush_blanks();
339	exit(0);
340}
341
342void
343flush_lines(int nflush)
344{
345	LINE *l;
346
347	while (--nflush >= 0) {
348		l = lines;
349		lines = l->l_next;
350		if (l->l_line) {
351			flush_blanks();
352			flush_line(l);
353		}
354		nblank_lines++;
355		if (l->l_line)
356			(void)free(l->l_line);
357		free_line(l);
358	}
359	if (lines)
360		lines->l_prev = NULL;
361}
362
363/*
364 * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
365 * is the number of half line feeds, otherwise it is the number of whole line
366 * feeds.
367 */
368void
369flush_blanks(void)
370{
371	int half, i, nb;
372
373	half = 0;
374	nb = nblank_lines;
375	if (nb & 1) {
376		if (fine)
377			half = 1;
378		else
379			nb++;
380	}
381	nb /= 2;
382	for (i = nb; --i >= 0;)
383		PUTC('\n');
384	if (half) {
385		PUTC('\033');
386		PUTC('9');
387		if (!nb)
388			PUTC('\r');
389	}
390	nblank_lines = 0;
391}
392
393/*
394 * Write a line to stdout taking care of space to tab conversion (-h flag)
395 * and character set shifts.
396 */
397void
398flush_line(LINE *l)
399{
400	CHAR *c, *endc;
401	int i, nchars, last_col, this_col;
402
403	last_col = 0;
404	nchars = l->l_line_len;
405
406	if (l->l_needs_sort) {
407		static CHAR *sorted;
408		static int count_size, *count, i, save, sorted_size, tot;
409
410		/*
411		 * Do an O(n) sort on l->l_line by column being careful to
412		 * preserve the order of characters in the same column.
413		 */
414		if (l->l_lsize > sorted_size) {
415			sorted_size = l->l_lsize;
416			if ((sorted = realloc(sorted,
417			    (unsigned)sizeof(CHAR) * sorted_size)) == NULL)
418				err(1, (char *)NULL);
419		}
420		if (l->l_max_col >= count_size) {
421			count_size = l->l_max_col + 1;
422			if ((count = realloc(count,
423			    (unsigned)sizeof(int) * count_size)) == NULL)
424				err(1, (char *)NULL);
425		}
426		memset(count, 0, sizeof(int) * l->l_max_col + 1);
427		for (i = nchars, c = l->l_line; --i >= 0; c++)
428			count[c->c_column]++;
429
430		/*
431		 * calculate running total (shifted down by 1) to use as
432		 * indices into new line.
433		 */
434		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
435			save = count[i];
436			count[i] = tot;
437			tot += save;
438		}
439
440		for (i = nchars, c = l->l_line; --i >= 0; c++)
441			sorted[count[c->c_column]++] = *c;
442		c = sorted;
443	} else
444		c = l->l_line;
445	while (nchars > 0) {
446		this_col = c->c_column;
447		endc = c;
448		do {
449			++endc;
450		} while (--nchars > 0 && this_col == endc->c_column);
451
452		/* if -b only print last character */
453		if (no_backspaces) {
454			c = endc - 1;
455			if (nchars > 0 &&
456			    this_col + c->c_width > endc->c_column)
457				continue;
458		}
459
460		if (this_col > last_col) {
461			int nspace = this_col - last_col;
462
463			if (compress_spaces && nspace > 1) {
464				while (1) {
465					int tab_col, tab_size;;
466
467					tab_col = (last_col + 8) & ~7;
468					if (tab_col > this_col)
469						break;
470					tab_size = tab_col - last_col;
471					if (tab_size == 1)
472						PUTC(' ');
473					else
474						PUTC('\t');
475					nspace -= tab_size;
476					last_col = tab_col;
477				}
478			}
479			while (--nspace >= 0)
480				PUTC(' ');
481			last_col = this_col;
482		}
483
484		for (;;) {
485			if (c->c_set != last_set) {
486				switch (c->c_set) {
487				case CS_NORMAL:
488					PUTC('\017');
489					break;
490				case CS_ALTERNATE:
491					PUTC('\016');
492				}
493				last_set = c->c_set;
494			}
495			PUTC(c->c_char);
496			if ((c + 1) < endc)
497				for (i = 0; i < c->c_width; i++)
498					PUTC('\b');
499			if (++c >= endc)
500				break;
501		}
502		last_col += (c - 1)->c_width;
503	}
504}
505
506#define	NALLOC 64
507
508static LINE *line_freelist;
509
510LINE *
511alloc_line(void)
512{
513	LINE *l;
514	int i;
515
516	if (!line_freelist) {
517		if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL)
518			err(1, (char *)NULL);
519		line_freelist = l;
520		for (i = 1; i < NALLOC; i++, l++)
521			l->l_next = l + 1;
522		l->l_next = NULL;
523	}
524	l = line_freelist;
525	line_freelist = l->l_next;
526
527	memset(l, 0, sizeof(LINE));
528	return (l);
529}
530
531void
532free_line(LINE *l)
533{
534
535	l->l_next = line_freelist;
536	line_freelist = l;
537}
538
539void
540usage(void)
541{
542
543	(void)fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n");
544	exit(1);
545}
546
547void
548dowarn(int line)
549{
550
551	warnx("warning: can't back up %s",
552		line < 0 ? "past first line" : "-- line already flushed");
553}
554