LXR busybox/libbb/device

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * Utility routines.
   4 *
   5 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
   6 *
   7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8 */
   9#include "libbb.h"
  10
  11/* try to open up the specified device */
  12int FAST_FUNC device_open(const char *device, int mode)
  13{
  14        int m, f, fd;
  15
  16        m = mode | O_NONBLOCK;
  17
  18        /* Retry up to 5 times */
  19        /* TODO: explain why it can't be considered insane */
  20        for (f = 0; f < 5; f++) {
  21                fd = open(device, m, 0600);
  22                if (fd >= 0)
  23                        break;
  24        }
  25        if (fd < 0)
  26                return fd;
  27        /* Reset original flags. */
  28        if (m != mode)
  29                fcntl(fd, F_SETFL, mode);
  30        return fd;
  31}
  32