freebsd-skq/usr.bin/basename/basename.c

140 lines
3.8 KiB
C

/*-
* Copyright (c) 1991, 1993, 1994
* 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
static char copyright[] =
"@(#) Copyright (c) 1991, 1993, 1994\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
static char sccsid[] = "@(#)basename.c 8.4 (Berkeley) 5/4/95";
#endif /* not lint */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
void usage __P((void));
int
main(argc, argv)
int argc;
char **argv;
{
char *p;
int ch;
while ((ch = getopt(argc, argv, "")) != EOF)
switch(ch) {
case '?':
default:
usage();
}
argc -= optind;
argv += optind;
if (argc != 1 && argc != 2)
usage();
/*
* (1) If string is // it is implementation defined whether steps (2)
* through (5) are skipped or processed.
*
* (2) If string consists entirely of slash characters, string shall
* be set to a single slash character. In this case, skip steps
* (3) through (5).
*/
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)
continue;
while (*--p == '/')
continue;
*++p = '\0';
/*
* (4) If there are any slash characters remaining in string, the
* prefix of string up to an including the last slash character
* in string shall be removed.
*/
while (--p >= *argv)
if (*p == '/')
break;
++p;
/*
* (5) If the suffix operand is present, is not identical to the
* characters remaining in string, and is identical to a suffix
* of the characters remaining in string, the suffix suffix
* shall be removed from string.
*/
if (*++argv) {
int suffixlen, stringlen, off;
suffixlen = strlen(*argv);
stringlen = strlen(p);
if (suffixlen < stringlen) {
off = stringlen - suffixlen;
if (!strcmp(p + off, *argv))
p[off] = '\0';
}
}
(void)printf("%s\n", p);
exit(0);
}
void
usage()
{
(void)fprintf(stderr, "usage: basename string [suffix]\n");
exit(1);
}