[TableGen][SystemZ] Correctly check the range of a leaf immediate (#119931)
[llvm-project.git] / libcxx / include / __cxx03 / __support / ibm / nanosleep.h
blob1b6883bbcc1118b41894bb8a1d8b1bb2e799e026
1 // -*- C++ -*-
2 //===----------------------------------------------------------------------===//
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
10 #ifndef _LIBCPP___CXX03___SUPPORT_IBM_NANOSLEEP_H
11 #define _LIBCPP___CXX03___SUPPORT_IBM_NANOSLEEP_H
13 #include <__cxx03/unistd.h>
15 inline int nanosleep(const struct timespec* __req, struct timespec* __rem) {
16 // The nanosleep() function is not available on z/OS. Therefore, we will call
17 // sleep() to sleep for whole seconds and usleep() to sleep for any remaining
18 // fraction of a second. Any remaining nanoseconds will round up to the next
19 // microsecond.
20 if (__req->tv_sec < 0 || __req->tv_nsec < 0 || __req->tv_nsec > 999999999) {
21 errno = EINVAL;
22 return -1;
24 long __micro_sec = (__req->tv_nsec + 999) / 1000;
25 time_t __sec = __req->tv_sec;
26 if (__micro_sec > 999999) {
27 ++__sec;
28 __micro_sec -= 1000000;
30 __sec = static_cast<time_t>(sleep(static_cast<unsigned int>(__sec)));
31 if (__sec) {
32 if (__rem) {
33 // Updating the remaining time to sleep in case of unsuccessful call to sleep().
34 __rem->tv_sec = __sec;
35 __rem->tv_nsec = __micro_sec * 1000;
37 errno = EINTR;
38 return -1;
40 if (__micro_sec) {
41 int __rt = usleep(static_cast<unsigned int>(__micro_sec));
42 if (__rt != 0 && __rem) {
43 // The usleep() does not provide the amount of remaining time upon its failure,
44 // so the time slept will be ignored.
45 __rem->tv_sec = 0;
46 __rem->tv_nsec = __micro_sec * 1000;
47 // The errno is already set.
48 return -1;
50 return __rt;
52 return 0;
55 #endif // _LIBCPP___CXX03___SUPPORT_IBM_NANOSLEEP_H