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/*
* Copyright (c) 1995, 1996, 1997 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* 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 Kungliga Tekniska
* Högskolan and its contributors.
*
* 4. Neither the name of the Institute 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 INSTITUTE 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 INSTITUTE 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 "krb_locl.h"
RCSID("$Id: k_flock.c,v 1.8 1997/04/01 08:18:30 joda Exp $");
#define K_OP_MASK (K_LOCK_SH | K_LOCK_EX | K_LOCK_UN)
int
k_flock(int fd, int operation)
{
#ifdef HAVE_FLOCK
int op = 0;
if (operation & K_LOCK_SH)
op |= LOCK_SH;
if (operation & K_LOCK_EX)
op |= LOCK_EX;
if (operation & K_LOCK_UN)
op |= LOCK_UN;
if (operation & K_LOCK_NB)
op |= LOCK_NB;
return flock(fd, op);
#elif defined(HAVE_FCNTL) && defined(F_SETLK)
struct flock arg;
int code, cmd;
arg.l_whence = SEEK_SET;
arg.l_start = 0;
arg.l_len = 0; /* means to EOF */
if (operation & K_LOCK_NB)
cmd = F_SETLK;
else
cmd = F_SETLKW; /* Blocking */
switch (operation & K_OP_MASK) {
case K_LOCK_UN:
arg.l_type = F_UNLCK;
code = fcntl(fd, F_SETLK, &arg);
break;
case K_LOCK_SH:
arg.l_type = F_RDLCK;
code = fcntl(fd, cmd, &arg);
break;
case K_LOCK_EX:
arg.l_type = F_WRLCK;
code = fcntl(fd, cmd, &arg);
break;
default:
errno = EINVAL;
code = -1;
break;
}
return code;
#else
return -1;
#endif /* !HAVE_FLOCK */
}
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