1 /*
2 * Copyright (c) 2015-2017 Dmitry V. Levin <ldv@altlinux.org>
3 * Copyright (c) 2017-2018 The strace developers.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #ifndef STRACE_NEGATED_ERRNO_H
30 #define STRACE_NEGATED_ERRNO_H
31
32 /*
33 * Check the syscall return value register value for whether it is
34 * a negated errno code indicating an error, or a success return value.
35 */
36 static inline bool
is_negated_errno(kernel_ulong_t val)37 is_negated_errno(kernel_ulong_t val)
38 {
39 kernel_ulong_t max = -(kernel_long_t) MAX_ERRNO_VALUE;
40
41 #ifndef current_klongsize
42 if (current_klongsize < sizeof(val)) {
43 val = (uint32_t) val;
44 max = (uint32_t) max;
45 }
46 #endif /* !current_klongsize */
47
48 return val >= max;
49 }
50
51 #endif /* !STRACE_NEGATED_ERRNO_H */
52