lib/libc/gen/devname.c

   1 /*
   2  * Copyright (c) 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * $FreeBSD: src/lib/libc/gen/devname.c,v 1.2.2.2 2001/07/31 20:10:19 tmm Exp $
  30  *
  31  * @(#)devname.c        8.2 (Berkeley) 4/29/95
  32  */
  33
  34 #include "namespace.h"
  35 #include <sys/types.h>
  36 #include <sys/stat.h>
  37 #include <sys/param.h>
  38 #include <sys/sysctl.h>
  39
  40 #include <err.h>
  41 #include <fcntl.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45 #include "un-namespace.h"
  46
  47 char *
  48 devname_r(dev_t dev, mode_t type, char *buf, size_t len)
  49 {
  50         size_t n = len;
  51
  52         if (sysctlbyname("kern.devname", buf, &n, &dev, sizeof(dev)) == 0)
  53                 return buf;
  54
  55         /* Just format it if failed to get its name */
  56         snprintf(buf, len, "#%c%d:0x%x",
  57             (type & S_IFMT) == S_IFCHR ? 'C' : 'B',
  58             major(dev), minor(dev));
  59
  60         return (buf);
  61 }
  62
  63 char *
  64 devname(dev_t dev, mode_t type)
  65 {
  66         static char buf[MAXPATHLEN];
  67
  68         strlcpy(buf, devname_r(dev, type, buf, sizeof(buf)), sizeof(buf));
  69
  70         return (buf);
  71 }