NetBSD/lib/libutil/getdiskrawname.c

137 lines
3.4 KiB
C

/* $NetBSD: getdiskrawname.c,v 1.5 2014/09/17 23:54:42 christos Exp $ */
/*-
* Copyright (c) 2012 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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>
__RCSID("$NetBSD: getdiskrawname.c,v 1.5 2014/09/17 23:54:42 christos Exp $");
#include <sys/stat.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <util.h>
#include <limits.h>
#include <unistd.h>
static const char *
resolve_link(char *buf, size_t bufsiz, const char *name)
{
const char *dp;
size_t nlen;
ssize_t dlen;
dlen = readlink(name, buf, bufsiz - 1);
if (dlen == -1)
return name;
buf[dlen] = '\0';
if (buf[0] != '/') {
dp = strrchr(name, '/');
if (dp != NULL) {
nlen = dp - name + 1;
if (nlen + 1 > bufsiz)
return NULL;
if (nlen + dlen + 1 > bufsiz)
return NULL;
memmove(buf + nlen, buf, (size_t)dlen + 1);
memcpy(buf, name, nlen);
}
}
return buf;
}
const char *
getdiskrawname(char *buf, size_t bufsiz, const char *name)
{
const char *dp;
struct stat st;
char dest[PATH_MAX];
if ((name = resolve_link(dest, sizeof(dest), name)) == NULL) {
errno = EINVAL;
return NULL;
}
dp = strrchr(name, '/');
if (stat(name, &st) == -1)
return NULL;
if (!S_ISBLK(st.st_mode)) {
errno = EFTYPE;
return NULL;
}
if (dp != NULL)
(void)snprintf(buf, bufsiz, "%.*s/r%s", (int)(dp - name), name, dp + 1);
else
(void)snprintf(buf, bufsiz, "r%s", name);
return buf;
}
const char *
getdiskcookedname(char *buf, size_t bufsiz, const char *name)
{
const char *dp;
struct stat st;
char dest[PATH_MAX];
if ((name = resolve_link(dest, sizeof(dest), name)) == NULL) {
errno = EINVAL;
return NULL;
}
dp = strrchr(name, '/');
if ((dp != NULL && dp[1] != 'r') || (dp == NULL && name[0] != 'r')) {
errno = EINVAL;
return NULL;
}
if (stat(name, &st) == -1)
return NULL;
if (!S_ISCHR(st.st_mode)) {
errno = EFTYPE;
return NULL;
}
if (dp != NULL)
(void)snprintf(buf, bufsiz, "%.*s/%s", (int)(dp - name), name, dp + 2);
else
(void)snprintf(buf, bufsiz, "%s", name + 1);
return buf;
}