Viewing file:  offset.h (1.85 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/*
* Copyright (C) 2004, 2005, 2007, 2008 Internet Systems Consortium, Inc. ("ISC")
* Copyright (C) 2000, 2001 Internet Software Consortium.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: offset.h,v 1.17 2008-12-01 23:47:45 tbox Exp $ */
#ifndef ISC_OFFSET_H
#define ISC_OFFSET_H 1
/*! \file
* \brief
* File offsets are operating-system dependent.
*/
#include <limits.h> /* Required for CHAR_BIT. */
#include <sys/types.h>
#include <stddef.h> /* For Linux Standard Base. */
typedef off_t isc_offset_t;
/*%
* POSIX says "Additionally, blkcnt_t and off_t are extended signed integral
* types", so the maximum value is all 1s except for the high bit.
* This definition is more complex than it really needs to be because it was
* crafted to keep both the SunOS 5.6 and the HP/UX 11 compilers quiet about
* integer overflow. For example, though this is equivalent to just left
* shifting 1 to the high bit and then inverting the bits, the SunOS compiler
* is unhappy about shifting a positive "1" to negative in a signed integer.
*/
#define ISC_OFFSET_MAXIMUM \
(~(((off_t)-1 >> (sizeof(off_t) * CHAR_BIT - 1)) \
<< (sizeof(off_t) * CHAR_BIT - 1)))
#endif /* ISC_OFFSET_H */
|