1 //===-- Implementation of sched_getcpuisset -------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "src/sched/sched_getcpuisset.h" 10 11 #include "src/__support/common.h" // LLVM_LIBC_FUNCTION 12 #include "src/__support/macros/config.h" // LIBC_NAMESPACE_DECL 13 #include "src/__support/macros/null_check.h" // LIBC_CRASH_ON_NULLPTR 14 15 #include "hdr/sched_macros.h" // NCPUBITS 16 #include "hdr/types/cpu_set_t.h" 17 #include "hdr/types/size_t.h" 18 19 namespace LIBC_NAMESPACE_DECL { 20 21 LLVM_LIBC_FUNCTION(int, __sched_getcpuisset, 22 (int cpu, const size_t cpuset_size, cpu_set_t *set)) { 23 LIBC_CRASH_ON_NULLPTR(set); 24 25 if (static_cast<size_t>(cpu) / 8 < cpuset_size) { 26 const size_t element_index = static_cast<size_t>(cpu) / NCPUBITS; 27 const size_t bit_position = static_cast<size_t>(cpu) % NCPUBITS; 28 29 const unsigned long mask = 1UL << bit_position; 30 return (set->__mask[element_index] & mask) != 0; 31 } 32 33 return 0; 34 } 35 36 } // namespace LIBC_NAMESPACE_DECL 37