NetBSD/usr.bin/dirname/dirname.c

140 lines
3.8 KiB
C

/*-
* Copyright (c) 1991 The Regents of the University of California.
* All rights reserved.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1991 The Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */
#ifndef lint
static char sccsid[] = "@(#)dirname.c 5.6 (Berkeley) 3/9/91";
#endif /* not lint */
#include <stdio.h>
#include <stdlib.h>
main(argc, argv)
int argc;
char **argv;
{
extern int optind;
register char *p;
int ch;
while ((ch = getopt(argc, argv, "")) != EOF)
switch(ch) {
case '?':
default:
usage();
}
argc -= optind;
argv += optind;
if (argc != 1)
usage();
/*
* (1) If string is //, skip steps (2) through (5).
* (2) If string consists entirely of slash characters, string
* shall be set to a single slash character. In this case,
* skip steps (3) through (8).
*/
for (p = *argv;; ++p) {
if (!*p) {
if (p > *argv)
(void)printf("/\n");
else
(void)printf(".\n");
exit(0);
}
if (*p != '/')
break;
}
/*
* (3) If there are any trailing slash characters in string, they
* shall be removed.
*/
for (; *p; ++p);
while (*--p == '/');
*++p = '\0';
/*
* (4) If there are no slash characters remaining in string,
* string shall be set to a single period character. In this
* case skip steps (5) through (8).
*
* (5) If there are any trailing nonslash characters in string,
* they shall be removed.
*/
while (--p >= *argv)
if (*p == '/')
break;
++p;
if (p == *argv) {
(void)printf(".\n");
exit(0);
}
/*
* (6) If the remaining string is //, it is implementation defined
* whether steps (7) and (8) are skipped or processed.
*
* This case has already been handled, as part of steps (1) and (2).
*/
/*
* (7) If there are any trailing slash characters in string, they
* shall be removed.
*/
while (--p >= *argv)
if (*p != '/')
break;
++p;
/*
* (8) If the remaining string is empty, string shall be set to
* a single slash character.
*/
*p = '\0';
(void)printf("%s\n", p == *argv ? "/" : *argv);
exit(0);
}
usage()
{
(void)fprintf(stderr, "usage: dirname path\n");
exit(1);
}