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settimeofday.c revision 1.10
      1  1.10    kardel /*	$NetBSD: settimeofday.c,v 1.10 2006/10/07 20:02:01 kardel Exp $ */
      2   1.1      manu 
      3   1.1      manu /*
      4   1.1      manu  * Copyright (c) 2001 The NetBSD Foundation, Inc.
      5   1.1      manu  * All rights reserved.
      6   1.1      manu  *
      7   1.1      manu  * This code is derived from software contributed to The NetBSD Foundation
      8   1.1      manu  * by Emmanuel Dreyfus.
      9   1.1      manu  *
     10   1.1      manu  * Redistribution and use in source and binary forms, with or without
     11   1.1      manu  * modification, are permitted provided that the following conditions
     12   1.1      manu  * are met:
     13   1.1      manu  * 1. Redistributions of source code must retain the above copyright
     14   1.1      manu  *    notice, this list of conditions and the following disclaimer.
     15   1.1      manu  * 2. Redistributions in binary form must reproduce the above copyright
     16   1.1      manu  *    notice, this list of conditions and the following disclaimer in the
     17   1.1      manu  *    documentation and/or other materials provided with the distribution.
     18   1.1      manu  * 3. The name of the author may not be used to endorse or promote products
     19   1.1      manu  *    derived from this software without specific prior written permission.
     20   1.1      manu  *
     21   1.1      manu  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     22   1.1      manu  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     23   1.1      manu  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     24   1.1      manu  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     25   1.1      manu  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
     26   1.1      manu  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     27   1.1      manu  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
     28   1.1      manu  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
     29   1.1      manu  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     30   1.1      manu  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     31   1.1      manu  * SUCH DAMAGE.
     32   1.1      manu  */
     33   1.1      manu 
     34   1.7     lukem #include <sys/cdefs.h>
     35   1.7     lukem #if defined(LIBC_SCCS) && !defined(lint)
     36  1.10    kardel __RCSID("$NetBSD: settimeofday.c,v 1.10 2006/10/07 20:02:01 kardel Exp $");
     37   1.7     lukem #endif /* LIBC_SCCS and not lint */
     38   1.7     lukem 
     39   1.1      manu #include "namespace.h"
     40   1.2   thorpej 
     41   1.1      manu #include <sys/types.h>
     42   1.1      manu #include <sys/ioctl.h>
     43   1.1      manu #include <sys/syscall.h>
     44   1.3      manu 
     45   1.1      manu #include <sys/clockctl.h>
     46   1.2   thorpej 
     47   1.3      manu #include <errno.h>
     48   1.2   thorpej #include <fcntl.h>
     49   1.2   thorpej #include <paths.h>
     50   1.2   thorpej #include <string.h>
     51   1.2   thorpej #include <time.h>
     52   1.2   thorpej #include <unistd.h>
     53   1.1      manu 
     54   1.1      manu #ifdef __weak_alias
     55   1.1      manu __weak_alias(settimeofday,_settimeofday)
     56   1.1      manu #endif
     57   1.1      manu 
     58  1.10    kardel int __clockctl_fd = -1;
     59   1.3      manu 
     60   1.1      manu int
     61   1.1      manu settimeofday(tv, tzp)
     62   1.1      manu 	const struct timeval *tv;
     63   1.6    kleink 	const void *tzp;
     64   1.1      manu {
     65   1.8  christos 	struct clockctl_settimeofday args;
     66   1.1      manu 	quad_t q;
     67   1.1      manu 	int rv;
     68   1.1      manu 
     69   1.3      manu 	/*
     70  1.10    kardel 	 * try syscal first and attempt to switch to clockctl
     71  1.10    kardel 	 * if that fails with EPERM
     72   1.3      manu 	 */
     73   1.3      manu 	if (__clockctl_fd == -1) {
     74   1.3      manu 		q = __syscall((quad_t)SYS_settimeofday, tv, tzp);
     75   1.3      manu 		if (/* LINTED constant */ sizeof (quad_t) == sizeof (register_t)
     76   1.3      manu 		    || /* LINTED constant */ BYTE_ORDER == LITTLE_ENDIAN)
     77   1.3      manu 			rv = (int)q;
     78   1.3      manu 		else
     79   1.3      manu 			rv = (int)((u_quad_t)q >> 32);
     80   1.3      manu 
     81   1.3      manu 		/*
     82  1.10    kardel 		 * switch to clockctl if we fail with EPERM, this
     83  1.10    kardel 		 * may be cause by an attempt to set the time backwards
     84  1.10    kardel 		 * but we should leave the access permission checking
     85  1.10    kardel 		 * entirely to the kernel
     86   1.3      manu 		 */
     87  1.10    kardel 		if (rv != -1 || errno != EPERM)
     88   1.3      manu 			return rv;
     89   1.3      manu 
     90  1.10    kardel 		__clockctl_fd = open(_PATH_CLOCKCTL, O_WRONLY, 0);
     91  1.10    kardel 		if (__clockctl_fd == -1) {
     92  1.10    kardel 			/* original error was EPERM - don't leak open errors */
     93  1.10    kardel 			errno = EPERM;
     94  1.10    kardel 			return -1;
     95   1.3      manu 		}
     96   1.3      manu 
     97   1.5        cb 		(void) fcntl(__clockctl_fd, F_SETFD, FD_CLOEXEC);
     98   1.3      manu 	}
     99   1.1      manu 
    100   1.1      manu 	/*
    101   1.3      manu 	 * If __clockctl_fd >=0, clockctl has already been open
    102   1.3      manu 	 * and used, so we carry on using it.
    103   1.1      manu 	 */
    104   1.8  christos 	args.tv = tv;
    105   1.8  christos 	args.tzp = tzp;
    106  1.10    kardel 	return ioctl(__clockctl_fd, CLOCKCTL_SETTIMEOFDAY, &args);
    107   1.1      manu }
    108