88 lines
2.5 KiB
C
88 lines
2.5 KiB
C
/*
|
|
* 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. 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.
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include <config.h>
|
|
#endif
|
|
|
|
#ifndef HAVE_FLOCK
|
|
RCSID("$Id: flock.c,v 1.1.1.2 2000/08/02 19:59:47 assar Exp $");
|
|
|
|
#include "roken.h"
|
|
|
|
|
|
#define OP_MASK (LOCK_SH | LOCK_EX | LOCK_UN)
|
|
|
|
int
|
|
flock(int fd, int operation)
|
|
{
|
|
#if 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 & LOCK_NB)
|
|
cmd = F_SETLK;
|
|
else
|
|
cmd = F_SETLKW; /* Blocking */
|
|
|
|
switch (operation & OP_MASK) {
|
|
case LOCK_UN:
|
|
arg.l_type = F_UNLCK;
|
|
code = fcntl(fd, F_SETLK, &arg);
|
|
break;
|
|
case LOCK_SH:
|
|
arg.l_type = F_RDLCK;
|
|
code = fcntl(fd, cmd, &arg);
|
|
break;
|
|
case 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
|
|
}
|
|
|
|
#endif
|
|
|