/usr.bin/colrm/colrm.c

  1/*-
  2 * Copyright (c) 1991, 1993
  3 *	The Regents of the University of California.  All rights reserved.
  4 *
  5 * Redistribution and use in source and binary forms, with or without
  6 * modification, are permitted provided that the following conditions
  7 * are met:
  8 * 1. Redistributions of source code must retain the above copyright
  9 *    notice, this list of conditions and the following disclaimer.
 10 * 2. Redistributions in binary form must reproduce the above copyright
 11 *    notice, this list of conditions and the following disclaimer in the
 12 *    documentation and/or other materials provided with the distribution.
 13 * 4. Neither the name of the University nor the names of its contributors
 14 *    may be used to endorse or promote products derived from this software
 15 *    without specific prior written permission.
 16 *
 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 27 * SUCH DAMAGE.
 28 */
 29
 30#ifndef lint
 31static const char copyright[] =
 32"@(#) Copyright (c) 1991, 1993\n\
 33	The Regents of the University of California.  All rights reserved.\n";
 34#endif
 35
 36#if 0
 37#ifndef lint
 38static char sccsid[] = "@(#)colrm.c	8.2 (Berkeley) 5/4/95";
 39#endif
 40#endif
 41
 42#include <sys/cdefs.h>
 43__FBSDID("$FreeBSD$");
 44
 45#include <sys/types.h>
 46#include <err.h>
 47#include <errno.h>
 48#include <limits.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
 56#define	TAB	8
 57
 58void check(FILE *);
 59static void usage(void);
 60
 61int
 62main(int argc, char *argv[])
 63{
 64	u_long column, start, stop;
 65	int ch, width;
 66	char *p;
 67
 68	setlocale(LC_ALL, "");
 69
 70	while ((ch = getopt(argc, argv, "")) != -1)
 71		switch(ch) {
 72		case '?':
 73		default:
 74			usage();
 75		}
 76	argc -= optind;
 77	argv += optind;
 78
 79	start = stop = 0;
 80	switch(argc) {
 81	case 2:
 82		stop = strtol(argv[1], &p, 10);
 83		if (stop <= 0 || *p)
 84			errx(1, "illegal column -- %s", argv[1]);
 85		/* FALLTHROUGH */
 86	case 1:
 87		start = strtol(argv[0], &p, 10);
 88		if (start <= 0 || *p)
 89			errx(1, "illegal column -- %s", argv[0]);
 90		break;
 91	case 0:
 92		break;
 93	default:
 94		usage();
 95	}
 96
 97	if (stop && start > stop)
 98		errx(1, "illegal start and stop columns");
 99
100	for (column = 0;;) {
101		switch (ch = getwchar()) {
102		case WEOF:
103			check(stdin);
104			break;
105		case '\b':
106			if (column)
107				--column;
108			break;
109		case '\n':
110			column = 0;
111			break;
112		case '\t':
113			column = (column + TAB) & ~(TAB - 1);
114			break;
115		default:
116			if ((width = wcwidth(ch)) > 0)
117				column += width;
118			break;
119		}
120
121		if ((!start || column < start || (stop && column > stop)) &&
122		    putwchar(ch) == WEOF)
123			check(stdout);
124	}
125}
126
127void
128check(FILE *stream)
129{
130	if (feof(stream))
131		exit(0);
132	if (ferror(stream))
133		err(1, "%s", stream == stdin ? "stdin" : "stdout");
134}
135
136void
137usage(void)
138{
139	(void)fprintf(stderr, "usage: colrm [start [stop]]\n");
140	exit(1);
141}
142