#include "lock.h"

#include <fcntl.h>
#include <sys/file.h>
#include <sys/types.h>
#include <unistd.h>

/**
  @file lock.c
  @author djb
  @ref qmail
  @brief locking of resources
*/

#ifdef HASFLOCK
int lock_ex(int fd)
{
  return flock(fd, LOCK_EX);
}

int lock_exnb(int fd)
{
  return flock(fd, LOCK_EX | LOCK_NB);
}

int lock_un(int fd)
{
  return flock(fd, LOCK_UN);
}
#else
int lock_ex(int fd)
{
  return lockf(fd, 1, 0);
}

int lock_exnb(int fd)
{
  return lockf(fd, 2, 0);
}

int lock_un(int fd)
{
  return lockf(fd, 0, 0);
}
#endif