33f3f40866
Even though POSIX allows us to return simply /dev/tty as a pathname identifying the controlling terminal of the running process, it is nicer if this function were actually useful, by returning the actual pathname of the controlling terminal. Implement ctermid() by using the kern.devname sysctl to resolve the actual name of /dev/tty. Don't use devname(3), since it may return bogus strings like #C:0x123.
71 lines
2.2 KiB
C
71 lines
2.2 KiB
C
/*-
|
|
* Copyright (c) 2011 Ed Schouten <ed@FreeBSD.org>
|
|
* 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/sysctl.h>
|
|
|
|
#include <errno.h>
|
|
#include <paths.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
|
|
#define LEN_PATH_DEV (sizeof(_PATH_DEV) - 1)
|
|
|
|
char *
|
|
ctermid(char *s)
|
|
{
|
|
static char def[sizeof(_PATH_DEV) + SPECNAMELEN];
|
|
struct stat sb;
|
|
size_t dlen;
|
|
int sverrno;
|
|
|
|
if (s == NULL) {
|
|
s = def;
|
|
dlen = sizeof(def) - LEN_PATH_DEV;
|
|
} else
|
|
dlen = L_ctermid - LEN_PATH_DEV;
|
|
strcpy(s, _PATH_TTY);
|
|
|
|
/* Attempt to perform a lookup of the actual TTY pathname. */
|
|
sverrno = errno;
|
|
if (stat(_PATH_TTY, &sb) == 0 && S_ISCHR(sb.st_mode))
|
|
(void)sysctlbyname("kern.devname", s + LEN_PATH_DEV,
|
|
&dlen, &sb.st_rdev, sizeof(sb.st_rdev));
|
|
errno = sverrno;
|
|
return (s);
|
|
}
|
|
|
|
char *
|
|
ctermid_r(char *s)
|
|
{
|
|
|
|
return (s != NULL ? ctermid(s) : NULL);
|
|
}
|