Revision control
++ // Copyright (C) 2023 Intel Corporation.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
++ // Qt-Security score:significant reason:default
++
++ #ifndef QFUTEX_LINUX_P_H
++ #define QFUTEX_LINUX_P_H
++
++ //
++ // W A R N I N G
++ // -------------
++ //
++ // This file is not part of the Qt API. It exists purely as an
++ // implementation detail. This header file may change from version to
++ // version without notice, or even be removed.
++ //
++ // We mean it.
++ //
++
++ #include <private/qcore_unix_p.h>
++ #include <qdeadlinetimer.h>
++ #include <qtsan_impl.h>
++
++ #include <asm/unistd.h>
++ #include <errno.h>
++ #include <limits.h>
++ #include <linux/futex.h>
++ #include <sys/syscall.h>
++ #include <unistd.h>
++
++ // RISC-V does not supply __NR_futex
++ #ifndef __NR_futex
++ # define __NR_futex __NR_futex_time64
++ #endif
++
++ #define QT_ALWAYS_USE_FUTEX
++
++ QT_BEGIN_NAMESPACE
++
++ namespace QtLinuxFutex {
++ constexpr inline bool futexAvailable() { return true; }
++
++ inline long _q_futex(int *addr, int op, int val, quintptr val2 = 0,
++ int *addr2 = nullptr, int val3 = 0) noexcept
++ {
++ QtTsan::futexRelease(addr, addr2);
++
++ // we use __NR_futex because some libcs (like Android's bionic) don't
++ // provide SYS_futex etc.
++ long result = syscall(__NR_futex, addr, op | FUTEX_PRIVATE_FLAG, val, val2, addr2, val3);
++
++ QtTsan::futexAcquire(addr, addr2);
++
++ return result;
++ }
++ template <typename T> int *addr(T *ptr)
++ {
++ int *int_addr = reinterpret_cast<int *>(ptr);
++ #if Q_BYTE_ORDER == Q_BIG_ENDIAN
++ if (sizeof(T) > sizeof(int))
++ int_addr++; //We want a pointer to the least significant half
++ #endif
++ return int_addr;
++ }
++
++ template <typename Atomic>
++ inline void futexWait(Atomic &futex, typename Atomic::Type expectedValue)
++ {
++ _q_futex(addr(&futex), FUTEX_WAIT, qintptr(expectedValue));
++ }
++ template <typename Atomic>
++ inline bool futexWait(Atomic &futex, typename Atomic::Type expectedValue, QDeadlineTimer deadline)
++ {
++ auto timeout = deadline.deadline<std::chrono::steady_clock>().time_since_epoch();
++ struct timespec ts = durationToTimespec(timeout);
++ long r = _q_futex(addr(&futex), FUTEX_WAIT_BITSET, qintptr(expectedValue), quintptr(&ts),
++ nullptr, FUTEX_BITSET_MATCH_ANY);
++ return r == 0 || errno != ETIMEDOUT;
++ }
++ template <typename Atomic> inline void futexWakeOne(Atomic &futex)
++ {
++ _q_futex(addr(&futex), FUTEX_WAKE, 1);
++ }
++ template <typename Atomic> inline void futexWakeAll(Atomic &futex)
++ {
++ _q_futex(addr(&futex), FUTEX_WAKE, INT_MAX);
++ }
++ template <typename Atomic> inline
++ void futexWakeOp(Atomic &futex1, int wake1, int wake2, Atomic &futex2, quint32 op)
++ {
++ _q_futex(addr(&futex1), FUTEX_WAKE_OP, wake1, wake2, addr(&futex2), op);
++ }} // namespace QtLinuxFutex
++ namespace QtFutex = QtLinuxFutex;
++
++ QT_END_NAMESPACE
++
++ #endif // QFUTEX_LINUX_P_H