mirror_zfs/include/os/freebsd/spl/sys/byteorder.h

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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or https://opensource.org/licenses/CDDL-1.0.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*
* $FreeBSD$
*/
/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* University Copyright- Copyright (c) 1982, 1986, 1988
* The Regents of the University of California
* All Rights Reserved
*
* University Acknowledgment- Portions of this document are derived from
* software developed by the University of California, Berkeley, and its
* contributors.
*/
#ifndef _OPENSOLARIS_SYS_BYTEORDER_H_
#define _OPENSOLARIS_SYS_BYTEORDER_H_
#include <sys/endian.h>
Reduce false positives from Static Analyzers Both Clang's Static Analyzer and Synopsys' Coverity would ignore assertions. Following Clang's advice, we annotate our assertions: https://clang-analyzer.llvm.org/annotations.html#custom_assertions This makes both Clang's Static Analyzer and Coverity properly identify assertions. This change reduced Clang's reported defects from 246 to 180. It also reduced the false positives reported by Coverityi by 10, while enabling Coverity to find 9 more defects that previously were false negatives. A couple examples of this would be CID-1524417 and CID-1524423. After submitting a build to coverity with the modified assertions, CID-1524417 disappeared while the report for CID-1524423 no longer claimed that the assertion tripped. Coincidentally, it turns out that it is possible to more accurately annotate our headers than the Coverity modelling file permits in the case of format strings. Since we can do that and this patch annotates headers whenever `__coverity_panic__()` would have been used in the model file, we drop all models that use `__coverity_panic__()` from the model file. Upon seeing the success in eliminating false positives involving assertions, it occurred to me that we could also modify our headers to eliminate coverity's false positives involving byte swaps. We now have coverity specific byteswap macros, that do nothing, to disable Coverity's false positives when we do byte swaps. This allowed us to also drop the byteswap definitions from the model file. Lastly, a model file update has been done beyond the mentioned deletions: * The definitions of `umem_alloc_aligned()`, `umem_alloc()` andi `umem_zalloc()` were originally implemented in a way that was intended to inform coverity that when KM_SLEEP has been passed these functions, they do not return NULL. A small error in how this was done was found, so we correct it. * Definitions for umem_cache_alloc() and umem_cache_free() have been added. In practice, no false positives were avoided by making these changes, but in the interest of correctness from future coverity builds, we make them anyway. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Ryan Moeller <ryan@iXsystems.com> Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu> Closes #13902
2022-10-01 01:30:12 +03:00
#ifdef __COVERITY__
/*
* Coverity's taint warnings from byteswapping are false positives for us.
* Suppress them by hiding byteswapping from Coverity.
*/
#define BSWAP_8(x) ((x) & 0xff)
#define BSWAP_16(x) ((x) & 0xffff)
#define BSWAP_32(x) ((x) & 0xffffffff)
#define BSWAP_64(x) (x)
#else /* __COVERITY__ */
/*
* Macros to reverse byte order
*/
#define BSWAP_8(x) ((x) & 0xff)
#define BSWAP_16(x) ((BSWAP_8(x) << 8) | BSWAP_8((x) >> 8))
#define BSWAP_32(x) ((BSWAP_16(x) << 16) | BSWAP_16((x) >> 16))
#define BSWAP_64(x) ((BSWAP_32(x) << 32) | BSWAP_32((x) >> 32))
Reduce false positives from Static Analyzers Both Clang's Static Analyzer and Synopsys' Coverity would ignore assertions. Following Clang's advice, we annotate our assertions: https://clang-analyzer.llvm.org/annotations.html#custom_assertions This makes both Clang's Static Analyzer and Coverity properly identify assertions. This change reduced Clang's reported defects from 246 to 180. It also reduced the false positives reported by Coverityi by 10, while enabling Coverity to find 9 more defects that previously were false negatives. A couple examples of this would be CID-1524417 and CID-1524423. After submitting a build to coverity with the modified assertions, CID-1524417 disappeared while the report for CID-1524423 no longer claimed that the assertion tripped. Coincidentally, it turns out that it is possible to more accurately annotate our headers than the Coverity modelling file permits in the case of format strings. Since we can do that and this patch annotates headers whenever `__coverity_panic__()` would have been used in the model file, we drop all models that use `__coverity_panic__()` from the model file. Upon seeing the success in eliminating false positives involving assertions, it occurred to me that we could also modify our headers to eliminate coverity's false positives involving byte swaps. We now have coverity specific byteswap macros, that do nothing, to disable Coverity's false positives when we do byte swaps. This allowed us to also drop the byteswap definitions from the model file. Lastly, a model file update has been done beyond the mentioned deletions: * The definitions of `umem_alloc_aligned()`, `umem_alloc()` andi `umem_zalloc()` were originally implemented in a way that was intended to inform coverity that when KM_SLEEP has been passed these functions, they do not return NULL. A small error in how this was done was found, so we correct it. * Definitions for umem_cache_alloc() and umem_cache_free() have been added. In practice, no false positives were avoided by making these changes, but in the interest of correctness from future coverity builds, we make them anyway. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Ryan Moeller <ryan@iXsystems.com> Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu> Closes #13902
2022-10-01 01:30:12 +03:00
#endif /* __COVERITY__ */
#define BMASK_8(x) ((x) & 0xff)
#define BMASK_16(x) ((x) & 0xffff)
#define BMASK_32(x) ((x) & 0xffffffff)
#define BMASK_64(x) (x)
/*
* Macros to convert from a specific byte order to/from native byte order
*/
#if BYTE_ORDER == _BIG_ENDIAN
#define BE_8(x) BMASK_8(x)
#define BE_16(x) BMASK_16(x)
#define BE_32(x) BMASK_32(x)
#define BE_64(x) BMASK_64(x)
#define LE_8(x) BSWAP_8(x)
#define LE_16(x) BSWAP_16(x)
#define LE_32(x) BSWAP_32(x)
#define LE_64(x) BSWAP_64(x)
#else
#define LE_8(x) BMASK_8(x)
#define LE_16(x) BMASK_16(x)
#define LE_32(x) BMASK_32(x)
#define LE_64(x) BMASK_64(x)
#define BE_8(x) BSWAP_8(x)
#define BE_16(x) BSWAP_16(x)
#define BE_32(x) BSWAP_32(x)
#define BE_64(x) BSWAP_64(x)
#endif
#if !defined(_STANDALONE)
#if BYTE_ORDER == _BIG_ENDIAN
#define htonll(x) BMASK_64(x)
#define ntohll(x) BMASK_64(x)
#else /* BYTE_ORDER == _LITTLE_ENDIAN */
#ifndef __LP64__
static __inline__ uint64_t
htonll(uint64_t n)
{
return ((((uint64_t)htonl(n)) << 32) + htonl(n >> 32));
}
static __inline__ uint64_t
ntohll(uint64_t n)
{
return ((((uint64_t)ntohl(n)) << 32) + ntohl(n >> 32));
}
#else /* !__LP64__ */
#define htonll(x) BSWAP_64(x)
#define ntohll(x) BSWAP_64(x)
#endif /* __LP64__ */
#endif /* BYTE_ORDER */
#endif /* _STANDALONE */
#define BE_IN32(xa) htonl(*((uint32_t *)(void *)(xa)))
#endif /* _OPENSOLARIS_SYS_BYTEORDER_H_ */