/usr.bin/col/col.c

  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 * 4. Neither the name of the University nor the names of its contributors
 17 *    may be used to endorse or promote products derived from this software
 18 *    without specific prior written permission.
 19 *
 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 30 * SUCH DAMAGE.
 31 */
 32
 33#ifndef lint
 34static const char copyright[] =
 35"@(#) Copyright (c) 1990, 1993, 1994\n\
 36	The Regents of the University of California.  All rights reserved.\n";
 37#endif
 38
 39#if 0
 40#ifndef lint
 41static char sccsid[] = "@(#)col.c	8.5 (Berkeley) 5/4/95";
 42#endif
 43#endif
 44
 45#include <sys/cdefs.h>
 46__FBSDID("$FreeBSD$");
 47
 48#include <err.h>
 49#include <locale.h>
 50#include <stdio.h>
 51#include <stdlib.h>
 52#include <string.h>
 53#include <unistd.h>
 54#include <wchar.h>
 55#include <wctype.h>
 56
 57#define	BS	'\b'		/* backspace */
 58#define	TAB	'\t'		/* tab */
 59#define	SPACE	' '		/* space */
 60#define	NL	'\n'		/* newline */
 61#define	CR	'\r'		/* carriage return */
 62#define	ESC	'\033'		/* escape */
 63#define	SI	'\017'		/* shift in to normal character set */
 64#define	SO	'\016'		/* shift out to alternate character set */
 65#define	VT	'\013'		/* vertical tab (aka reverse line feed) */
 66#define	RLF	'\007'		/* ESC-07 reverse line feed */
 67#define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
 68#define	FHLF	'\011'		/* ESC-011 forward half-line feed */
 69
 70/* build up at least this many lines before flushing them out */
 71#define	BUFFER_MARGIN		32
 72
 73typedef char CSET;
 74
 75typedef struct char_str {
 76#define	CS_NORMAL	1
 77#define	CS_ALTERNATE	2
 78	short		c_column;	/* column character is in */
 79	CSET		c_set;		/* character set (currently only 2) */
 80	wchar_t		c_char;		/* character in question */
 81	int		c_width;	/* character width */
 82} CHAR;
 83
 84typedef struct line_str LINE;
 85struct line_str {
 86	CHAR	*l_line;		/* characters on the line */
 87	LINE	*l_prev;		/* previous line */
 88	LINE	*l_next;		/* next line */
 89	int	l_lsize;		/* allocated sizeof l_line */
 90	int	l_line_len;		/* strlen(l_line) */
 91	int	l_needs_sort;		/* set if chars went in out of order */
 92	int	l_max_col;		/* max column in the line */
 93};
 94
 95static LINE   *alloc_line(void);
 96static void	dowarn(int);
 97static void	flush_line(LINE *);
 98static void	flush_lines(int);
 99static void	flush_blanks(void);
100static void	free_line(LINE *);
101static void	usage(void);
102
103static CSET	last_set;		/* char_set of last char printed */
104static LINE    *lines;
105static int	compress_spaces;	/* if doing space -> tab conversion */
106static int	fine;			/* if `fine' resolution (half lines) */
107static int	max_bufd_lines;		/* max # lines to keep in memory */
108static int	nblank_lines;		/* # blanks after last flushed line */
109static int	no_backspaces;		/* if not to output any backspaces */
110static int	pass_unknown_seqs;	/* pass unknown control sequences */
111
112#define	PUTC(ch) \
113	do {					\
114		if (putwchar(ch) == WEOF)	\
115			errx(1, "write error");	\
116	} while (0)
117
118int
119main(int argc, char **argv)
120{
121	wint_t ch;
122	CHAR *c;
123	CSET cur_set;			/* current character set */
124	LINE *l;			/* current line */
125	int extra_lines;		/* # of lines above first line */
126	int cur_col;			/* current column */
127	int cur_line;			/* line number of current position */
128	int max_line;			/* max value of cur_line */
129	int this_line;			/* line l points to */
130	int nflushd_lines;		/* number of lines that were flushed */
131	int adjust, opt, warned, width;
132
133	(void)setlocale(LC_CTYPE, "");
134
135	max_bufd_lines = 128;
136	compress_spaces = 1;		/* compress spaces into tabs */
137	while ((opt = getopt(argc, argv, "bfhl:px")) != -1)
138		switch (opt) {
139		case 'b':		/* do not output backspaces */
140			no_backspaces = 1;
141			break;
142		case 'f':		/* allow half forward line feeds */
143			fine = 1;
144			break;
145		case 'h':		/* compress spaces into tabs */
146			compress_spaces = 1;
147			break;
148		case 'l':		/* buffered line count */
149			if ((max_bufd_lines = atoi(optarg)) <= 0)
150				errx(1, "bad -l argument %s", optarg);
151			break;
152		case 'p':		/* pass unknown control sequences */
153			pass_unknown_seqs = 1;
154			break;
155		case 'x':		/* do not compress spaces into tabs */
156			compress_spaces = 0;
157			break;
158		case '?':
159		default:
160			usage();
161		}
162
163	if (optind != argc)
164		usage();
165
166	/* this value is in half lines */
167	max_bufd_lines *= 2;
168
169	adjust = cur_col = extra_lines = warned = 0;
170	cur_line = max_line = nflushd_lines = this_line = 0;
171	cur_set = last_set = CS_NORMAL;
172	lines = l = alloc_line();
173
174	while ((ch = getwchar()) != WEOF) {
175		if (!iswgraph(ch)) {
176			switch (ch) {
177			case BS:		/* can't go back further */
178				if (cur_col == 0)
179					continue;
180				--cur_col;
181				continue;
182			case CR:
183				cur_col = 0;
184				continue;
185			case ESC:		/* just ignore EOF */
186				switch(getwchar()) {
187				case RLF:
188					cur_line -= 2;
189					break;
190				case RHLF:
191					cur_line--;
192					break;
193				case FHLF:
194					cur_line++;
195					if (cur_line > max_line)
196						max_line = cur_line;
197				}
198				continue;
199			case NL:
200				cur_line += 2;
201				if (cur_line > max_line)
202					max_line = cur_line;
203				cur_col = 0;
204				continue;
205			case SPACE:
206				++cur_col;
207				continue;
208			case SI:
209				cur_set = CS_NORMAL;
210				continue;
211			case SO:
212				cur_set = CS_ALTERNATE;
213				continue;
214			case TAB:		/* adjust column */
215				cur_col |= 7;
216				++cur_col;
217				continue;
218			case VT:
219				cur_line -= 2;
220				continue;
221			}
222			if (iswspace(ch)) {
223				if ((width = wcwidth(ch)) > 0)
224					cur_col += width;
225				continue;
226			}
227			if (!pass_unknown_seqs)
228				continue;
229		}
230
231		/* Must stuff ch in a line - are we at the right one? */
232		if (cur_line != this_line - adjust) {
233			LINE *lnew;
234			int nmove;
235
236			adjust = 0;
237			nmove = cur_line - this_line;
238			if (!fine) {
239				/* round up to next line */
240				if (cur_line & 1) {
241					adjust = 1;
242					nmove++;
243				}
244			}
245			if (nmove < 0) {
246				for (; nmove < 0 && l->l_prev; nmove++)
247					l = l->l_prev;
248				if (nmove) {
249					if (nflushd_lines == 0) {
250						/*
251						 * Allow backup past first
252						 * line if nothing has been
253						 * flushed yet.
254						 */
255						for (; nmove < 0; nmove++) {
256							lnew = alloc_line();
257							l->l_prev = lnew;
258							lnew->l_next = l;
259							l = lines = lnew;
260							extra_lines++;
261						}
262					} else {
263						if (!warned++)
264							dowarn(cur_line);
265						cur_line -= nmove;
266					}
267				}
268			} else {
269				/* may need to allocate here */
270				for (; nmove > 0 && l->l_next; nmove--)
271					l = l->l_next;
272				for (; nmove > 0; nmove--) {
273					lnew = alloc_line();
274					lnew->l_prev = l;
275					l->l_next = lnew;
276					l = lnew;
277				}
278			}
279			this_line = cur_line + adjust;
280			nmove = this_line - nflushd_lines;
281			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
282				nflushd_lines += nmove - max_bufd_lines;
283				flush_lines(nmove - max_bufd_lines);
284			}
285		}
286		/* grow line's buffer? */
287		if (l->l_line_len + 1 >= l->l_lsize) {
288			int need;
289
290			need = l->l_lsize ? l->l_lsize * 2 : 90;
291			if ((l->l_line = realloc(l->l_line,
292			    (unsigned)need * sizeof(CHAR))) == NULL)
293				err(1, (char *)NULL);
294			l->l_lsize = need;
295		}
296		c = &l->l_line[l->l_line_len++];
297		c->c_char = ch;
298		c->c_set = cur_set;
299		c->c_column = cur_col;
300		c->c_width = wcwidth(ch);
301		/*
302		 * If things are put in out of order, they will need sorting
303		 * when it is flushed.
304		 */
305		if (cur_col < l->l_max_col)
306			l->l_needs_sort = 1;
307		else
308			l->l_max_col = cur_col;
309		if (c->c_width > 0)
310			cur_col += c->c_width;
311	}
312	if (ferror(stdin))
313		err(1, NULL);
314	if (max_line == 0)
315		exit(0);	/* no lines, so just exit */
316
317	/* goto the last line that had a character on it */
318	for (; l->l_next; l = l->l_next)
319		this_line++;
320	flush_lines(this_line - nflushd_lines + extra_lines + 1);
321
322	/* make sure we leave things in a sane state */
323	if (last_set != CS_NORMAL)
324		PUTC('\017');
325
326	/* flush out the last few blank lines */
327	nblank_lines = max_line - this_line;
328	if (max_line & 1)
329		nblank_lines++;
330	else if (!nblank_lines)
331		/* missing a \n on the last line? */
332		nblank_lines = 2;
333	flush_blanks();
334	exit(0);
335}
336
337static void
338flush_lines(int nflush)
339{
340	LINE *l;
341
342	while (--nflush >= 0) {
343		l = lines;
344		lines = l->l_next;
345		if (l->l_line) {
346			flush_blanks();
347			flush_line(l);
348		}
349		nblank_lines++;
350		if (l->l_line)
351			(void)free(l->l_line);
352		free_line(l);
353	}
354	if (lines)
355		lines->l_prev = NULL;
356}
357
358/*
359 * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
360 * is the number of half line feeds, otherwise it is the number of whole line
361 * feeds.
362 */
363static void
364flush_blanks(void)
365{
366	int half, i, nb;
367
368	half = 0;
369	nb = nblank_lines;
370	if (nb & 1) {
371		if (fine)
372			half = 1;
373		else
374			nb++;
375	}
376	nb /= 2;
377	for (i = nb; --i >= 0;)
378		PUTC('\n');
379	if (half) {
380		PUTC('\033');
381		PUTC('9');
382		if (!nb)
383			PUTC('\r');
384	}
385	nblank_lines = 0;
386}
387
388/*
389 * Write a line to stdout taking care of space to tab conversion (-h flag)
390 * and character set shifts.
391 */
392static void
393flush_line(LINE *l)
394{
395	CHAR *c, *endc;
396	int i, j, nchars, last_col, save, this_col, tot;
397
398	last_col = 0;
399	nchars = l->l_line_len;
400
401	if (l->l_needs_sort) {
402		static CHAR *sorted;
403		static int count_size, *count, sorted_size;
404
405		/*
406		 * Do an O(n) sort on l->l_line by column being careful to
407		 * preserve the order of characters in the same column.
408		 */
409		if (l->l_lsize > sorted_size) {
410			sorted_size = l->l_lsize;
411			if ((sorted = realloc(sorted,
412			    (unsigned)sizeof(CHAR) * sorted_size)) == NULL)
413				err(1, (char *)NULL);
414		}
415		if (l->l_max_col >= count_size) {
416			count_size = l->l_max_col + 1;
417			if ((count = realloc(count,
418			    (unsigned)sizeof(int) * count_size)) == NULL)
419				err(1, (char *)NULL);
420		}
421		memset(count, 0, sizeof(int) * l->l_max_col + 1);
422		for (i = nchars, c = l->l_line; --i >= 0; c++)
423			count[c->c_column]++;
424
425		/*
426		 * calculate running total (shifted down by 1) to use as
427		 * indices into new line.
428		 */
429		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
430			save = count[i];
431			count[i] = tot;
432			tot += save;
433		}
434
435		for (i = nchars, c = l->l_line; --i >= 0; c++)
436			sorted[count[c->c_column]++] = *c;
437		c = sorted;
438	} else
439		c = l->l_line;
440	while (nchars > 0) {
441		this_col = c->c_column;
442		endc = c;
443		do {
444			++endc;
445		} while (--nchars > 0 && this_col == endc->c_column);
446
447		/* if -b only print last character */
448		if (no_backspaces) {
449			c = endc - 1;
450			if (nchars > 0 &&
451			    this_col + c->c_width > endc->c_column)
452				continue;
453		}
454
455		if (this_col > last_col) {
456			int nspace = this_col - last_col;
457
458			if (compress_spaces && nspace > 1) {
459				while (1) {
460					int tab_col, tab_size;
461
462					tab_col = (last_col + 8) & ~7;
463					if (tab_col > this_col)
464						break;
465					tab_size = tab_col - last_col;
466					if (tab_size == 1)
467						PUTC(' ');
468					else
469						PUTC('\t');
470					nspace -= tab_size;
471					last_col = tab_col;
472				}
473			}
474			while (--nspace >= 0)
475				PUTC(' ');
476			last_col = this_col;
477		}
478
479		for (;;) {
480			if (c->c_set != last_set) {
481				switch (c->c_set) {
482				case CS_NORMAL:
483					PUTC('\017');
484					break;
485				case CS_ALTERNATE:
486					PUTC('\016');
487				}
488				last_set = c->c_set;
489			}
490			PUTC(c->c_char);
491			if ((c + 1) < endc)
492				for (j = 0; j < c->c_width; j++)
493					PUTC('\b');
494			if (++c >= endc)
495				break;
496		}
497		last_col += (c - 1)->c_width;
498	}
499}
500
501#define	NALLOC 64
502
503static LINE *line_freelist;
504
505static LINE *
506alloc_line(void)
507{
508	LINE *l;
509	int i;
510
511	if (!line_freelist) {
512		if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL)
513			err(1, (char *)NULL);
514		line_freelist = l;
515		for (i = 1; i < NALLOC; i++, l++)
516			l->l_next = l + 1;
517		l->l_next = NULL;
518	}
519	l = line_freelist;
520	line_freelist = l->l_next;
521
522	memset(l, 0, sizeof(LINE));
523	return (l);
524}
525
526static void
527free_line(LINE *l)
528{
529
530	l->l_next = line_freelist;
531	line_freelist = l;
532}
533
534static void
535usage(void)
536{
537
538	(void)fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n");
539	exit(1);
540}
541
542static void
543dowarn(int line)
544{
545
546	warnx("warning: can't back up %s",
547		line < 0 ? "past first line" : "-- line already flushed");
548}