freebsd-dev/lib/libc/gen/dirname.c
Xin LI 7b1fac0035 Sync with OpenBSD's dirname(3) - license change, avoid strcpy() over
string constant, use memcpy() instead of strncpy() and improve code
readibility.  No functional change.
2008-11-03 05:19:45 +00:00

78 lines
1.9 KiB
C

/* $OpenBSD: dirname.c,v 1.13 2005/08/08 08:05:33 espie Exp $ */
/*
* Copyright (c) 1997, 2004 Todd C. Miller <Todd.Miller@courtesan.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <errno.h>
#include <libgen.h>
#include <stdlib.h>
#include <string.h>
#include <sys/param.h>
char *
dirname(const char *path)
{
static char *dname = NULL;
size_t len;
const char *endp;
if (dname == NULL) {
dname = (char *)malloc(MAXPATHLEN);
if (dname == NULL)
return(NULL);
}
/* Empty or NULL string gets treated as "." */
if (path == NULL || *path == '\0') {
dname[0] = '.';
dname[1] = '\0';
return (dname);
}
/* Strip any trailing slashes */
endp = path + strlen(path) - 1;
while (endp > path && *endp == '/')
endp--;
/* Find the start of the dir */
while (endp > path && *endp != '/')
endp--;
/* Either the dir is "/" or there are no slashes */
if (endp == path) {
dname[0] = *endp == '/' ? '/' : '.';
dname[1] = '\0';
return (dname);
} else {
/* Move forward past the separating slashes */
do {
endp--;
} while (endp > path && *endp == '/');
}
len = endp - path + 1;
if (len >= MAXPATHLEN) {
errno = ENAMETOOLONG;
return (NULL);
}
memcpy(dname, path, len);
dname[len] = '\0';
return (dname);
}