col.c revision 132825 
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 132825 2004-07-29 07:28:26Z tjr $");
51
52#include <err.h>
53#include <locale.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57#include <unistd.h>
58#include <wchar.h>
59#include <wctype.h>
60
61#define	BS	'\b'		/* backspace */
62#define	TAB	'\t'		/* tab */
63#define	SPACE	' '		/* space */
64#define	NL	'\n'		/* newline */
65#define	CR	'\r'		/* carriage return */
66#define	ESC	'\033'		/* escape */
67#define	SI	'\017'		/* shift in to normal character set */
68#define	SO	'\016'		/* shift out to alternate character set */
69#define	VT	'\013'		/* vertical tab (aka reverse line feed) */
70#define	RLF	'\007'		/* ESC-07 reverse line feed */
71#define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
72#define	FHLF	'\011'		/* ESC-011 forward half-line feed */
73
74/* build up at least this many lines before flushing them out */
75#define	BUFFER_MARGIN		32
76
77typedef char CSET;
78
79typedef struct char_str {
80#define	CS_NORMAL	1
81#define	CS_ALTERNATE	2
82	short		c_column;	/* column character is in */
83	CSET		c_set;		/* character set (currently only 2) */
84	wchar_t		c_char;		/* character in question */
85	int		c_width;	/* character width */
86} CHAR;
87
88typedef struct line_str LINE;
89struct line_str {
90	CHAR	*l_line;		/* characters on the line */
91	LINE	*l_prev;		/* previous line */
92	LINE	*l_next;		/* next line */
93	int	l_lsize;		/* allocated sizeof l_line */
94	int	l_line_len;		/* strlen(l_line) */
95	int	l_needs_sort;		/* set if chars went in out of order */
96	int	l_max_col;		/* max column in the line */
97};
98
99LINE   *alloc_line(void);
100void	dowarn(int);
101void	flush_line(LINE *);
102void	flush_lines(int);
103void	flush_blanks(void);
104void	free_line(LINE *);
105void	usage(void);
106
107CSET	last_set;		/* char_set of last char printed */
108LINE   *lines;
109int	compress_spaces;	/* if doing space -> tab conversion */
110int	fine;			/* if `fine' resolution (half lines) */
111int	max_bufd_lines;		/* max # lines to keep in memory */
112int	nblank_lines;		/* # blanks after last flushed line */
113int	no_backspaces;		/* if not to output any backspaces */
114int	pass_unknown_seqs;	/* pass unknown control sequences */
115
116#define	PUTC(ch) \
117	do {					\
118		if (putwchar(ch) == WEOF)	\
119			errx(1, "write error");	\
120	} while (0)
121
122int
123main(int argc, char **argv)
124{
125	wint_t ch;
126	CHAR *c;
127	CSET cur_set;			/* current character set */
128	LINE *l;			/* current line */
129	int extra_lines;		/* # of lines above first line */
130	int cur_col;			/* current column */
131	int cur_line;			/* line number of current position */
132	int max_line;			/* max value of cur_line */
133	int this_line;			/* line l points to */
134	int nflushd_lines;		/* number of lines that were flushed */
135	int adjust, opt, warned, width;
136
137	(void)setlocale(LC_CTYPE, "");
138
139	max_bufd_lines = 128;
140	compress_spaces = 1;		/* compress spaces into tabs */
141	while ((opt = getopt(argc, argv, "bfhl:px")) != -1)
142		switch (opt) {
143		case 'b':		/* do not output backspaces */
144			no_backspaces = 1;
145			break;
146		case 'f':		/* allow half forward line feeds */
147			fine = 1;
148			break;
149		case 'h':		/* compress spaces into tabs */
150			compress_spaces = 1;
151			break;
152		case 'l':		/* buffered line count */
153			if ((max_bufd_lines = atoi(optarg)) <= 0)
154				errx(1, "bad -l argument %s", optarg);
155			break;
156		case 'p':		/* pass unknown control sequences */
157			pass_unknown_seqs = 1;
158			break;
159		case 'x':		/* do not compress spaces into tabs */
160			compress_spaces = 0;
161			break;
162		case '?':
163		default:
164			usage();
165		}
166
167	if (optind != argc)
168		usage();
169
170	/* this value is in half lines */
171	max_bufd_lines *= 2;
172
173	adjust = cur_col = extra_lines = warned = 0;
174	cur_line = max_line = nflushd_lines = this_line = 0;
175	cur_set = last_set = CS_NORMAL;
176	lines = l = alloc_line();
177
178	while ((ch = getwchar()) != WEOF) {
179		if (!iswgraph(ch)) {
180			switch (ch) {
181			case BS:		/* can't go back further */
182				if (cur_col == 0)
183					continue;
184				--cur_col;
185				continue;
186			case CR:
187				cur_col = 0;
188				continue;
189			case ESC:		/* just ignore EOF */
190				switch(getwchar()) {
191				case RLF:
192					cur_line -= 2;
193					break;
194				case RHLF:
195					cur_line--;
196					break;
197				case FHLF:
198					cur_line++;
199					if (cur_line > max_line)
200						max_line = cur_line;
201				}
202				continue;
203			case NL:
204				cur_line += 2;
205				if (cur_line > max_line)
206					max_line = cur_line;
207				cur_col = 0;
208				continue;
209			case SPACE:
210				++cur_col;
211				continue;
212			case SI:
213				cur_set = CS_NORMAL;
214				continue;
215			case SO:
216				cur_set = CS_ALTERNATE;
217				continue;
218			case TAB:		/* adjust column */
219				cur_col |= 7;
220				++cur_col;
221				continue;
222			case VT:
223				cur_line -= 2;
224				continue;
225			}
226			if (iswspace(ch)) {
227				if ((width = wcwidth(ch)) > 0)
228					cur_col += width;
229				continue;
230			}
231			if (!pass_unknown_seqs)
232				continue;
233		}
234
235		/* Must stuff ch in a line - are we at the right one? */
236		if (cur_line != this_line - adjust) {
237			LINE *lnew;
238			int nmove;
239
240			adjust = 0;
241			nmove = cur_line - this_line;
242			if (!fine) {
243				/* round up to next line */
244				if (cur_line & 1) {
245					adjust = 1;
246					nmove++;
247				}
248			}
249			if (nmove < 0) {
250				for (; nmove < 0 && l->l_prev; nmove++)
251					l = l->l_prev;
252				if (nmove) {
253					if (nflushd_lines == 0) {
254						/*
255						 * Allow backup past first
256						 * line if nothing has been
257						 * flushed yet.
258						 */
259						for (; nmove < 0; nmove++) {
260							lnew = alloc_line();
261							l->l_prev = lnew;
262							lnew->l_next = l;
263							l = lines = lnew;
264							extra_lines++;
265						}
266					} else {
267						if (!warned++)
268							dowarn(cur_line);
269						cur_line -= nmove;
270					}
271				}
272			} else {
273				/* may need to allocate here */
274				for (; nmove > 0 && l->l_next; nmove--)
275					l = l->l_next;
276				for (; nmove > 0; nmove--) {
277					lnew = alloc_line();
278					lnew->l_prev = l;
279					l->l_next = lnew;
280					l = lnew;
281				}
282			}
283			this_line = cur_line + adjust;
284			nmove = this_line - nflushd_lines;
285			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
286				nflushd_lines += nmove - max_bufd_lines;
287				flush_lines(nmove - max_bufd_lines);
288			}
289		}
290		/* grow line's buffer? */
291		if (l->l_line_len + 1 >= l->l_lsize) {
292			int need;
293
294			need = l->l_lsize ? l->l_lsize * 2 : 90;
295			if ((l->l_line = realloc(l->l_line,
296			    (unsigned)need * sizeof(CHAR))) == NULL)
297				err(1, (char *)NULL);
298			l->l_lsize = need;
299		}
300		c = &l->l_line[l->l_line_len++];
301		c->c_char = ch;
302		c->c_set = cur_set;
303		c->c_column = cur_col;
304		c->c_width = wcwidth(ch);
305		/*
306		 * If things are put in out of order, they will need sorting
307		 * when it is flushed.
308		 */
309		if (cur_col < l->l_max_col)
310			l->l_needs_sort = 1;
311		else
312			l->l_max_col = cur_col;
313		if (c->c_width > 0)
314			cur_col += c->c_width;
315	}
316	if (ferror(stdin))
317		err(1, NULL);
318	if (max_line == 0)
319		exit(0);	/* no lines, so just exit */
320
321	/* goto the last line that had a character on it */
322	for (; l->l_next; l = l->l_next)
323		this_line++;
324	flush_lines(this_line - nflushd_lines + extra_lines + 1);
325
326	/* make sure we leave things in a sane state */
327	if (last_set != CS_NORMAL)
328		PUTC('\017');
329
330	/* flush out the last few blank lines */
331	nblank_lines = max_line - this_line;
332	if (max_line & 1)
333		nblank_lines++;
334	else if (!nblank_lines)
335		/* missing a \n on the last line? */
336		nblank_lines = 2;
337	flush_blanks();
338	exit(0);
339}
340
341void
342flush_lines(int nflush)
343{
344	LINE *l;
345
346	while (--nflush >= 0) {
347		l = lines;
348		lines = l->l_next;
349		if (l->l_line) {
350			flush_blanks();
351			flush_line(l);
352		}
353		nblank_lines++;
354		if (l->l_line)
355			(void)free(l->l_line);
356		free_line(l);
357	}
358	if (lines)
359		lines->l_prev = NULL;
360}
361
362/*
363 * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
364 * is the number of half line feeds, otherwise it is the number of whole line
365 * feeds.
366 */
367void
368flush_blanks(void)
369{
370	int half, i, nb;
371
372	half = 0;
373	nb = nblank_lines;
374	if (nb & 1) {
375		if (fine)
376			half = 1;
377		else
378			nb++;
379	}
380	nb /= 2;
381	for (i = nb; --i >= 0;)
382		PUTC('\n');
383	if (half) {
384		PUTC('\033');
385		PUTC('9');
386		if (!nb)
387			PUTC('\r');
388	}
389	nblank_lines = 0;
390}
391
392/*
393 * Write a line to stdout taking care of space to tab conversion (-h flag)
394 * and character set shifts.
395 */
396void
397flush_line(LINE *l)
398{
399	CHAR *c, *endc;
400	int i, nchars, last_col, this_col;
401
402	last_col = 0;
403	nchars = l->l_line_len;
404
405	if (l->l_needs_sort) {
406		static CHAR *sorted;
407		static int count_size, *count, i, save, sorted_size, tot;
408
409		/*
410		 * Do an O(n) sort on l->l_line by column being careful to
411		 * preserve the order of characters in the same column.
412		 */
413		if (l->l_lsize > sorted_size) {
414			sorted_size = l->l_lsize;
415			if ((sorted = realloc(sorted,
416			    (unsigned)sizeof(CHAR) * sorted_size)) == NULL)
417				err(1, (char *)NULL);
418		}
419		if (l->l_max_col >= count_size) {
420			count_size = l->l_max_col + 1;
421			if ((count = realloc(count,
422			    (unsigned)sizeof(int) * count_size)) == NULL)
423				err(1, (char *)NULL);
424		}
425		memset(count, 0, sizeof(int) * l->l_max_col + 1);
426		for (i = nchars, c = l->l_line; --i >= 0; c++)
427			count[c->c_column]++;
428
429		/*
430		 * calculate running total (shifted down by 1) to use as
431		 * indices into new line.
432		 */
433		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
434			save = count[i];
435			count[i] = tot;
436			tot += save;
437		}
438
439		for (i = nchars, c = l->l_line; --i >= 0; c++)
440			sorted[count[c->c_column]++] = *c;
441		c = sorted;
442	} else
443		c = l->l_line;
444	while (nchars > 0) {
445		this_col = c->c_column;
446		endc = c;
447		do {
448			++endc;
449		} while (--nchars > 0 && this_col == endc->c_column);
450
451		/* if -b only print last character */
452		if (no_backspaces) {
453			c = endc - 1;
454			if (nchars > 0 &&
455			    this_col + c->c_width > endc->c_column)
456				continue;
457		}
458
459		if (this_col > last_col) {
460			int nspace = this_col - last_col;
461
462			if (compress_spaces && nspace > 1) {
463				while (1) {
464					int tab_col, tab_size;;
465
466					tab_col = (last_col + 8) & ~7;
467					if (tab_col > this_col)
468						break;
469					tab_size = tab_col - last_col;
470					if (tab_size == 1)
471						PUTC(' ');
472					else
473						PUTC('\t');
474					nspace -= tab_size;
475					last_col = tab_col;
476				}
477			}
478			while (--nspace >= 0)
479				PUTC(' ');
480			last_col = this_col;
481		}
482
483		for (;;) {
484			if (c->c_set != last_set) {
485				switch (c->c_set) {
486				case CS_NORMAL:
487					PUTC('\017');
488					break;
489				case CS_ALTERNATE:
490					PUTC('\016');
491				}
492				last_set = c->c_set;
493			}
494			PUTC(c->c_char);
495			if ((c + 1) < endc)
496				for (i = 0; i < c->c_width; i++)
497					PUTC('\b');
498			if (++c >= endc)
499				break;
500		}
501		last_col += (c - 1)->c_width;
502	}
503}
504
505#define	NALLOC 64
506
507static LINE *line_freelist;
508
509LINE *
510alloc_line(void)
511{
512	LINE *l;
513	int i;
514
515	if (!line_freelist) {
516		if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL)
517			err(1, (char *)NULL);
518		line_freelist = l;
519		for (i = 1; i < NALLOC; i++, l++)
520			l->l_next = l + 1;
521		l->l_next = NULL;
522	}
523	l = line_freelist;
524	line_freelist = l->l_next;
525
526	memset(l, 0, sizeof(LINE));
527	return (l);
528}
529
530void
531free_line(LINE *l)
532{
533
534	l->l_next = line_freelist;
535	line_freelist = l;
536}
537
538void
539usage(void)
540{
541
542	(void)fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n");
543	exit(1);
544}
545
546void
547dowarn(int line)
548{
549
550	warnx("warning: can't back up %s",
551		line < 0 ? "past first line" : "-- line already flushed");
552}
553