minix/usr.bin/fold/fold.c

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/* $NetBSD: fold.c,v 1.17 2011/09/04 20:24:59 joerg Exp $ */
/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kevin Ruddy.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1990, 1993\
The Regents of the University of California. All rights reserved.");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)fold.c 8.1 (Berkeley) 6/6/93";
#endif
__RCSID("$NetBSD: fold.c,v 1.17 2011/09/04 20:24:59 joerg Exp $");
#endif /* not lint */
#include <limits.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <wchar.h>
#include <err.h>
#define DEFLINEWIDTH 80
static void fold(int);
static int new_column_position(int, wint_t);
__dead static void usage(void);
static int count_bytes = 0;
static int split_words = 0;
int
main(int argc, char **argv)
{
int ch;
int width;
char *p;
setlocale(LC_CTYPE, "");
setprogname(argv[0]);
width = -1;
while ((ch = getopt(argc, argv, "0123456789bsw:")) != -1)
switch (ch) {
case 'b':
count_bytes = 1;
break;
case 's':
split_words = 1;
break;
case 'w':
if ((width = atoi(optarg)) <= 0)
errx(1, "illegal width value");
break;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
if (width == -1) {
p = argv[optind - 1];
if (p[0] == '-' && p[1] == ch && !p[2])
width = atoi(++p);
else
width = atoi(argv[optind] + 1);
}
break;
default:
usage();
}
argv += optind;
argc -= optind;
if (width == -1)
width = DEFLINEWIDTH;
if (!*argv)
fold(width);
else for (; *argv; ++argv)
if (!freopen(*argv, "r", stdin)) {
err (1, "%s", *argv);
/* NOTREACHED */
} else
fold(width);
exit(0);
}
/*
* Fold the contents of standard input to fit within WIDTH columns
* (or bytes) and write to standard output.
*
* If split_words is set, split the line at the last space character
* on the line. This flag necessitates storing the line in a buffer
* until the current column > width, or a newline or EOF is read.
*
* The buffer can grow larger than WIDTH due to backspaces and carriage
* returns embedded in the input stream.
*/
static void
fold(int width)
{
static wchar_t *buf = NULL;
wchar_t *nbuf;
static int buf_max = 0;
wint_t ch;
int col, indx, i;
col = indx = 0;
while ((ch = getwchar()) != WEOF) {
if (ch == L'\n') {
if (indx != 0) {
for (i = 0; i < indx; i++)
putwchar(buf[i]);
}
putwchar(L'\n');
col = indx = 0;
continue;
}
col = new_column_position (col, ch);
if (col > width) {
int last_space;
#ifdef __GNUC__
last_space = 0; /* XXX gcc */
#endif
if (split_words) {
for (i = 0, last_space = -1; i < indx; i++)
if (buf[i] == L' ')
last_space = i;
}
if (split_words && last_space != -1) {
for (i = 0; i < last_space; i++)
putwchar(buf[i]);
/* increase last_space here, so we skip trailing whitespace */
last_space++;
wmemmove (buf, buf+last_space, indx-last_space);
indx -= last_space;
col = 0;
for (i = 0; i < indx; i++) {
col = new_column_position (col, buf[i]);
}
} else {
for (i = 0; i < indx; i++)
putwchar(buf[i]);
col = indx = 0;
}
putwchar('\n');
/* calculate the column position for the next line. */
col = new_column_position (col, ch);
}
if (indx + 1 > buf_max) {
/* Allocate buffer in LINE_MAX increments */
if ((nbuf = realloc (buf, buf_max + 2048)) == NULL) {
err (1, "realloc");
/* NOTREACHED */
}
buf = nbuf;
buf_max += 2048;
}
buf[indx++] = ch;
}
if (indx != 0) {
for (i = 0; i < indx; i++)
putwchar(buf[i]);
}
}
/*
* calculate the column position
*/
static int
new_column_position (int col, wint_t ch)
{
int w;
if (!count_bytes) {
switch (ch) {
case L'\b':
if (col > 0)
--col;
break;
case L'\r':
col = 0;
break;
case L'\t':
col = (col + 8) & ~7;
break;
default:
w = wcwidth(ch);
if (w > 0)
col += w;
break;
}
} else {
char dummy[MB_LEN_MAX];
/* XXX: we assume stateless encoding */
col += wcrtomb(dummy, ch, NULL);
}
return col;
}
static void
usage(void)
{
(void)fprintf(stderr,
"usage: %s [-bs] [-w width] [file ...]\n", getprogname());
exit(1);
}