1c8af87873
posix standard on the topic.
153 lines
3.8 KiB
C
153 lines
3.8 KiB
C
/*-
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* Copyright (c) 1990, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* Kevin Ruddy.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#ifndef lint
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static char copyright[] =
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"@(#) Copyright (c) 1990, 1993\n\
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The Regents of the University of California. All rights reserved.\n";
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#endif /* not lint */
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#ifndef lint
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static char sccsid[] = "@(#)fold.c 8.1 (Berkeley) 6/6/93";
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#endif /* not lint */
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#include <stdio.h>
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#include <string.h>
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#define DEFLINEWIDTH 80
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main(argc, argv)
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int argc;
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char **argv;
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{
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extern int errno, optind;
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extern char *optarg;
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register int ch;
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int width;
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char *p;
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width = -1;
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while ((ch = getopt(argc, argv, "0123456789w:")) != -1)
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switch (ch) {
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case 'w':
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if ((width = atoi(optarg)) <= 0) {
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(void)fprintf(stderr,
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"fold: illegal width value.\n");
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exit(1);
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}
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break;
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case '0': case '1': case '2': case '3': case '4':
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case '5': case '6': case '7': case '8': case '9':
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if (width == -1) {
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p = argv[optind - 1];
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if (p[0] == '-' && p[1] == ch && !p[2])
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width = atoi(++p);
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else
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width = atoi(argv[optind] + 1);
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}
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break;
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default:
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(void)fprintf(stderr,
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"usage: fold [-w width] [file ...]\n");
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exit(1);
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}
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argv += optind;
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argc -= optind;
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if (width == -1)
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width = DEFLINEWIDTH;
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if (!*argv)
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fold(width);
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else for (; *argv; ++argv)
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if (!freopen(*argv, "r", stdin)) {
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(void)fprintf(stderr,
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"fold: %s: %s\n", *argv, strerror(errno));
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exit(1);
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} else
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fold(width);
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exit(0);
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}
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fold(width)
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register int width;
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{
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register int ch, col, new;
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for (col = 0;;) {
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switch (ch = getchar()) {
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case EOF:
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return;
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case '\b':
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new = col ? col - 1 : 0;
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break;
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case '\n':
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case '\r':
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new = 0;
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break;
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case '\t':
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new = (col + 8) & ~7;
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break;
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default:
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new = col + 1;
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break;
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}
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if (new > width) {
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putchar('\n');
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col = 0;
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}
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putchar(ch);
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switch (ch) {
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case '\b':
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if (col > 0)
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--col;
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break;
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case '\n':
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case '\r':
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col = 0;
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break;
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case '\t':
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col += 8;
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col &= ~7;
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break;
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default:
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++col;
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break;
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}
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}
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}
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