pppd/plugins/radius/lock.c

   1 /*
   2  * $Id: lock.c,v 1.1 2004/11/14 07:26:26 paulus Exp $
   3  *
   4  * Copyright (C) 1997 Lars Fenneberg
   5  *
   6  * See the file COPYRIGHT for the respective terms and conditions.
   7  * If the file is missing contact me at lf@elemental.net
   8  * and I'll send you a copy.
   9  *
  10  */
  11
  12 #include "includes.h"
  13 #include <unistd.h>
  14 #include <fcntl.h>
  15
  16 int do_lock_exclusive(int fd)
  17 {
  18         struct flock fl;
  19         int res;
  20
  21         memset((void *)&fl, 0, sizeof(fl));
  22
  23         fl.l_type = F_WRLCK;
  24         fl.l_whence = fl.l_start = 0;
  25         fl.l_len = 0; /* 0 means "to end of file" */
  26
  27         res = fcntl(fd, F_SETLK, &fl);
  28
  29         if ((res == -1) && (errno == EAGAIN))
  30                 errno = EWOULDBLOCK;
  31
  32         return res;
  33 }
  34
  35 int do_unlock(int fd)
  36 {
  37         struct flock fl;
  38
  39         memset((void *)&fl, 0, sizeof(fl));
  40
  41         fl.l_type = F_UNLCK;
  42         fl.l_whence = fl.l_start = 0;
  43         fl.l_len = 0; /* 0 means "to end of file" */
  44
  45         return fcntl(fd, F_SETLK, &fl);
  46 }