r3/linux/semevent-linux.cpp

9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync/* $Id$ */
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync/** @file
5b281ba489ca18f0380d7efc7a5108b606cce449vboxsync * IPRT - Event Semaphore, Linux (2.6.x+).
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync */
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync/*
e64031e20c39650a7bc902a3e1aba613b9415deevboxsync * Copyright (C) 2006-2010 Oracle Corporation
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync *
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * This file is part of VirtualBox Open Source Edition (OSE), as
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * available from http://www.virtualbox.org. This file is free software;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * you can redistribute it and/or modify it under the terms of the GNU
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * General Public License (GPL) as published by the Free Software
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * Foundation, in version 2 as it comes in the "COPYING" file of the
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync *
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * The contents of this file may alternatively be used under the terms
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * of the Common Development and Distribution License Version 1.0
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * VirtualBox OSE distribution, in which case the provisions of the
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * CDDL are applicable instead of those of the GPL.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync *
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * You may elect to license modified versions of this file under the
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * terms and conditions of either the GPL or the CDDL or both.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync */
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
3aad980b92149dd95a1ab72ddb8d11d61a28ace6vboxsync#include <features.h>
ceea06560fe5d384c1ed7ed0f8d5b69504456fccvboxsync#if __GLIBC_PREREQ(2,6) && !defined(IPRT_WITH_FUTEX_BASED_SEMS)
3aad980b92149dd95a1ab72ddb8d11d61a28ace6vboxsync
0a7b20727716a00270f358a1c546473d8c36e8f3vboxsync/*
0a7b20727716a00270f358a1c546473d8c36e8f3vboxsync * glibc 2.6 fixed a serious bug in the mutex implementation. We wrote this
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync * linux specific event semaphores code in order to work around the bug. We
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync * will fall back on the pthread-based implementation if glibc is known to
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync * contain the bug fix.
0a7b20727716a00270f358a1c546473d8c36e8f3vboxsync *
ad27e1d5e48ca41245120c331cc88b50464813cevboxsync * The external reference to epoll_pwait is a hack which prevents that we link
0a7b20727716a00270f358a1c546473d8c36e8f3vboxsync * against glibc < 2.6.
0a7b20727716a00270f358a1c546473d8c36e8f3vboxsync */
0a7b20727716a00270f358a1c546473d8c36e8f3vboxsync#include "../posix/semevent-posix.cpp"
3aad980b92149dd95a1ab72ddb8d11d61a28ace6vboxsyncasm volatile (".global epoll_pwait");
3aad980b92149dd95a1ab72ddb8d11d61a28ace6vboxsync
3aad980b92149dd95a1ab72ddb8d11d61a28ace6vboxsync#else /* glibc < 2.6 */
3aad980b92149dd95a1ab72ddb8d11d61a28ace6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync/*******************************************************************************
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync*   Header Files                                                               *
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync*******************************************************************************/
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#include <iprt/semaphore.h>
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#include "internal/iprt.h"
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#include <iprt/asm.h>
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#include <iprt/assert.h>
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#include <iprt/err.h>
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#include <iprt/lockvalidator.h>
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#include <iprt/mem.h>
7ccd30dd4bbced565b32c255a11640cd4093abb6vboxsync#include <iprt/time.h>
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#include "internal/magics.h"
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync#include "internal/mem.h"
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#include "internal/strict.h"
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#include <errno.h>
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#include <limits.h>
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#include <pthread.h>
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#include <unistd.h>
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#include <sys/time.h>
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#include <sys/syscall.h>
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#if 0 /* With 2.6.17 futex.h has become C++ unfriendly. */
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync# include <linux/futex.h>
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#else
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync# define FUTEX_WAIT 0
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync# define FUTEX_WAKE 1
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync#endif
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync/*******************************************************************************
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync*   Structures and Typedefs                                                    *
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync*******************************************************************************/
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync/**
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * Linux (single wakup) event semaphore.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync */
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsyncstruct RTSEMEVENTINTERNAL
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync{
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    /** Magic value. */
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    intptr_t volatile   iMagic;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    /** The futex state variable.
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync     * 0 means not signalled.
d605d5391db09e6395a1c091f148f4b86af84bd3vboxsync       1 means signalled. */
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    uint32_t volatile   fSignalled;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    /** The number of waiting threads */
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    int32_t volatile    cWaiters;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#ifdef RTSEMEVENT_STRICT
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    /** Signallers. */
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    RTLOCKVALRECSHRD    Signallers;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    /** Indicates that lock validation should be performed. */
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    bool volatile       fEverHadSignallers;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#endif
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync    /** The creation flags. */
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync    uint32_t            fFlags;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync};
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync/**
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync * Wrapper for the futex syscall.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync */
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsyncstatic long sys_futex(uint32_t volatile *uaddr, int op, int val, struct timespec *utime, int32_t *uaddr2, int val3)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync{
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    errno = 0;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    long rc = syscall(__NR_futex, uaddr, op, val, utime, uaddr2, val3);
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    if (rc < 0)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    {
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        Assert(rc == -1);
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        rc = -errno;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    }
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    return rc;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync}
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsyncRTDECL(int)  RTSemEventCreate(PRTSEMEVENT phEventSem)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync{
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync    return RTSemEventCreateEx(phEventSem, 0 /*fFlags*/, NIL_RTLOCKVALCLASS, NULL);
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync}
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsyncRTDECL(int)  RTSemEventCreateEx(PRTSEMEVENT phEventSem, uint32_t fFlags, RTLOCKVALCLASS hClass, const char *pszNameFmt, ...)
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync{
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync    AssertReturn(!(fFlags & ~(RTSEMEVENT_FLAGS_NO_LOCK_VAL | RTSEMEVENT_FLAGS_BOOTSTRAP_HACK)), VERR_INVALID_PARAMETER);
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync    Assert(!(fFlags & RTSEMEVENT_FLAGS_BOOTSTRAP_HACK) || (fFlags & RTSEMEVENT_FLAGS_NO_LOCK_VAL));
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    /*
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     * Allocate semaphore handle.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     */
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync    struct RTSEMEVENTINTERNAL *pThis;
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync    if (!(fFlags & RTSEMEVENT_FLAGS_BOOTSTRAP_HACK))
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync        pThis = (struct RTSEMEVENTINTERNAL *)RTMemAlloc(sizeof(struct RTSEMEVENTINTERNAL));
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync    else
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync        pThis = (struct RTSEMEVENTINTERNAL *)rtMemBaseAlloc(sizeof(struct RTSEMEVENTINTERNAL));
89dfdbb56cf9dddad3c7685b41bda1e4e4c1d6f9vboxsync    if (pThis)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    {
89dfdbb56cf9dddad3c7685b41bda1e4e4c1d6f9vboxsync        pThis->iMagic = RTSEMEVENT_MAGIC;
89dfdbb56cf9dddad3c7685b41bda1e4e4c1d6f9vboxsync        pThis->cWaiters = 0;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        pThis->fSignalled = 0;
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync        pThis->fFlags = fFlags;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#ifdef RTSEMEVENT_STRICT
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync        if (!pszNameFmt)
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync        {
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync            static uint32_t volatile s_iSemEventAnon = 0;
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync            RTLockValidatorRecSharedInit(&pThis->Signallers, hClass, RTLOCKVAL_SUB_CLASS_ANY, pThis,
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync                                         true /*fSignaller*/, !(fFlags & RTSEMEVENT_FLAGS_NO_LOCK_VAL),
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync                                         "RTSemEvent-%u", ASMAtomicIncU32(&s_iSemEventAnon) - 1);
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync        }
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync        else
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync        {
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync            va_list va;
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync            va_start(va, pszNameFmt);
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync            RTLockValidatorRecSharedInitV(&pThis->Signallers, hClass, RTLOCKVAL_SUB_CLASS_ANY, pThis,
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync                                          true /*fSignaller*/, !(fFlags & RTSEMEVENT_FLAGS_NO_LOCK_VAL),
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync                                          pszNameFmt, va);
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync            va_end(va);
2e42e0850e182e37277fe28ba5b5d1c37018e783vboxsync        }
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync        pThis->fEverHadSignallers = false;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#endif
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync        *phEventSem = pThis;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        return VINF_SUCCESS;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    }
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    return  VERR_NO_MEMORY;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync}
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsyncRTDECL(int)  RTSemEventDestroy(RTSEMEVENT hEventSem)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync{
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    /*
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     * Validate input.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     */
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync    if (pThis == NIL_RTSEMEVENT)
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync        return VINF_SUCCESS;
660fd430a3a8cfa16505d04c7c577acf89d45a40vboxsync    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
660fd430a3a8cfa16505d04c7c577acf89d45a40vboxsync    AssertReturn(pThis->iMagic == RTSEMEVENT_MAGIC, VERR_INVALID_HANDLE);
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    /*
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     * Invalidate the semaphore and wake up anyone waiting on it.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     */
cce6b7c4e45848f22615d68ba5865b71abbfac95vboxsync    ASMAtomicXchgSize(&pThis->iMagic, RTSEMEVENT_MAGIC | UINT32_C(0x80000000));
89dfdbb56cf9dddad3c7685b41bda1e4e4c1d6f9vboxsync    if (ASMAtomicXchgS32(&pThis->cWaiters, INT32_MIN / 2) > 0)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    {
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        sys_futex(&pThis->fSignalled, FUTEX_WAKE, INT_MAX, NULL, NULL, 0);
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        usleep(1000);
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    }
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    /*
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     * Free the semaphore memory and be gone.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     */
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#ifdef RTSEMEVENT_STRICT
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    RTLockValidatorRecSharedDelete(&pThis->Signallers);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#endif
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync    if (!(pThis->fFlags & RTSEMEVENT_FLAGS_BOOTSTRAP_HACK))
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync        RTMemFree(pThis);
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync    else
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync        rtMemBaseFree(pThis);
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    return VINF_SUCCESS;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync}
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsyncRTDECL(int)  RTSemEventSignal(RTSEMEVENT hEventSem)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync{
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    /*
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     * Validate input.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     */
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    AssertReturn(pThis->iMagic == RTSEMEVENT_MAGIC, VERR_INVALID_HANDLE);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#ifdef RTSEMEVENT_STRICT
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    if (pThis->fEverHadSignallers)
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    {
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync        int rc9 = RTLockValidatorRecSharedCheckSignaller(&pThis->Signallers, NIL_RTTHREAD);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync        if (RT_FAILURE(rc9))
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync            return rc9;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    }
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#endif
cce6b7c4e45848f22615d68ba5865b71abbfac95vboxsync
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    ASMAtomicWriteU32(&pThis->fSignalled, 1);
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    if (ASMAtomicReadS32(&pThis->cWaiters) < 1)
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        return VINF_SUCCESS;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    /* somebody is waiting, try wake up one of them. */
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    long cWoken = sys_futex(&pThis->fSignalled, FUTEX_WAKE, 1, NULL, NULL, 0);
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    if (RT_LIKELY(cWoken >= 0))
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        return VINF_SUCCESS;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    if (RT_UNLIKELY(pThis->iMagic != RTSEMEVENT_MAGIC))
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        return VERR_SEM_DESTROYED;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    return VERR_INVALID_PARAMETER;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync}
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
b79e4344bf4eb8033fd06d560cd864192728bd0bvboxsyncstatic int rtSemEventWait(RTSEMEVENT hEventSem, RTMSINTERVAL cMillies, bool fAutoResume)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync{
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    PCRTLOCKVALSRCPOS pSrcPos = NULL;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    /*
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     * Validate input.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     */
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    AssertReturn(pThis->iMagic == RTSEMEVENT_MAGIC, VERR_INVALID_HANDLE);
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    /*
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     * Quickly check whether it's signaled.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     */
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    /** @todo this isn't fair if someone is already waiting on it.  They should
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync     *        have the first go at it!
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync     *  (ASMAtomicReadS32(&pThis->cWaiters) == 0 || !cMillies) && ... */
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    if (ASMAtomicCmpXchgU32(&pThis->fSignalled, 0, 1))
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        return VINF_SUCCESS;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    /*
d605d5391db09e6395a1c091f148f4b86af84bd3vboxsync     * Convert the timeout value.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     */
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    struct timespec ts;
f9e38e609bea9e849b27173024dc82d93bcbf5fcvboxsync    struct timespec *pTimeout = NULL;
7ccd30dd4bbced565b32c255a11640cd4093abb6vboxsync    uint64_t u64End = 0; /* shut up gcc */
e190faad3061288ae099cd3ea8a858bd224c00a7vboxsync    if (cMillies != RT_INDEFINITE_WAIT)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    {
d605d5391db09e6395a1c091f148f4b86af84bd3vboxsync        if (!cMillies)
d605d5391db09e6395a1c091f148f4b86af84bd3vboxsync            return VERR_TIMEOUT;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        ts.tv_sec  = cMillies / 1000;
839735dffe669517793471bfac0775fd19db414avboxsync        ts.tv_nsec = (cMillies % 1000) * UINT32_C(1000000);
839735dffe669517793471bfac0775fd19db414avboxsync        u64End = RTTimeSystemNanoTS() + cMillies * UINT64_C(1000000);
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        pTimeout = &ts;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    }
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    ASMAtomicIncS32(&pThis->cWaiters);
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    /*
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     * The wait loop.
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync     */
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#ifdef RTSEMEVENT_STRICT
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync    RTTHREAD hThreadSelf = !(pThis->fFlags & RTSEMEVENT_FLAGS_BOOTSTRAP_HACK)
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync                         ? RTThreadSelfAutoAdopt()
418b9db49fbc652ef9c3f030fdc0f1a322403d95vboxsync                         : RTThreadSelf();
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#else
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    RTTHREAD hThreadSelf = RTThreadSelf();
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#endif
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    int rc = VINF_SUCCESS;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    for (;;)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    {
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#ifdef RTSEMEVENT_STRICT
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync        if (pThis->fEverHadSignallers)
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync        {
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync            rc = RTLockValidatorRecSharedCheckBlocking(&pThis->Signallers, hThreadSelf, pSrcPos, false,
2805b95732a8d26015a397626b96049a6e6573e7vboxsync                                                       cMillies, RTTHREADSTATE_EVENT, true);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync            if (RT_FAILURE(rc))
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync                break;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync        }
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#endif
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync        RTThreadBlocking(hThreadSelf, RTTHREADSTATE_EVENT, true);
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        long lrc = sys_futex(&pThis->fSignalled, FUTEX_WAIT, 0, pTimeout, NULL, 0);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync        RTThreadUnblocked(hThreadSelf, RTTHREADSTATE_EVENT);
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        if (RT_UNLIKELY(pThis->iMagic != RTSEMEVENT_MAGIC))
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        {
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync            rc = VERR_SEM_DESTROYED;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync            break;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        }
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        if (RT_LIKELY(lrc == 0 || lrc == -EWOULDBLOCK))
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        {
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync            /* successful wakeup or fSignalled > 0 in the meantime */
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync            if (ASMAtomicCmpXchgU32(&pThis->fSignalled, 0, 1))
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync                break;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        }
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        else if (lrc == -ETIMEDOUT)
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        {
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync            rc = VERR_TIMEOUT;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync            break;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        }
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        else if (lrc == -EINTR)
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync        {
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync            if (!fAutoResume)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync            {
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync                rc = VERR_INTERRUPTED;
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync                break;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync            }
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        }
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        else
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        {
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync            /* this shouldn't happen! */
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync            AssertMsgFailed(("rc=%ld errno=%d\n", lrc, errno));
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync            rc = RTErrConvertFromErrno(lrc);
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync            break;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync        }
7e10aea6606a51d35041e5a85f9e4f1bd19c4062vboxsync        /* adjust the relative timeout */
e190faad3061288ae099cd3ea8a858bd224c00a7vboxsync        if (pTimeout)
7e10aea6606a51d35041e5a85f9e4f1bd19c4062vboxsync        {
0a79c9258d8fae34fa527f125009ab507561b4edvboxsync            int64_t i64Diff = u64End - RTTimeSystemNanoTS();
0a79c9258d8fae34fa527f125009ab507561b4edvboxsync            if (i64Diff < 1000)
7e10aea6606a51d35041e5a85f9e4f1bd19c4062vboxsync            {
7e10aea6606a51d35041e5a85f9e4f1bd19c4062vboxsync                rc = VERR_TIMEOUT;
7e10aea6606a51d35041e5a85f9e4f1bd19c4062vboxsync                break;
7e10aea6606a51d35041e5a85f9e4f1bd19c4062vboxsync            }
839735dffe669517793471bfac0775fd19db414avboxsync            ts.tv_sec  = (uint64_t)i64Diff / UINT32_C(1000000000);
839735dffe669517793471bfac0775fd19db414avboxsync            ts.tv_nsec = (uint64_t)i64Diff % UINT32_C(1000000000);
7e10aea6606a51d35041e5a85f9e4f1bd19c4062vboxsync        }
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    }
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    ASMAtomicDecS32(&pThis->cWaiters);
65146b9eb3e96dbac286e55faa020bbfd74037d7vboxsync    return rc;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync}
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
b79e4344bf4eb8033fd06d560cd864192728bd0bvboxsyncRTDECL(int)  RTSemEventWait(RTSEMEVENT hEventSem, RTMSINTERVAL cMillies)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync{
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync    int rc = rtSemEventWait(hEventSem, cMillies, true);
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    Assert(rc != VERR_INTERRUPTED);
f9e38e609bea9e849b27173024dc82d93bcbf5fcvboxsync    Assert(rc != VERR_TIMEOUT || cMillies != RT_INDEFINITE_WAIT);
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync    return rc;
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync}
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
b79e4344bf4eb8033fd06d560cd864192728bd0bvboxsyncRTDECL(int)  RTSemEventWaitNoResume(RTSEMEVENT hEventSem, RTMSINTERVAL cMillies)
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync{
a734bb626f889ee3334bfc381be194b4ec56aae6vboxsync    return rtSemEventWait(hEventSem, cMillies, false);
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync}
9e5c26690d45216629b5f588aced8fcfb68c23b6vboxsync
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsyncRTDECL(void) RTSemEventSetSignaller(RTSEMEVENT hEventSem, RTTHREAD hThread)
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync{
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#ifdef RTSEMEVENT_STRICT
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    AssertPtrReturnVoid(pThis);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    AssertReturnVoid(pThis->iMagic == RTSEMEVENT_MAGIC);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    ASMAtomicWriteBool(&pThis->fEverHadSignallers, true);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    RTLockValidatorRecSharedResetOwner(&pThis->Signallers, hThread, NULL);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#endif
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync}
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsyncRTDECL(void) RTSemEventAddSignaller(RTSEMEVENT hEventSem, RTTHREAD hThread)
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync{
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#ifdef RTSEMEVENT_STRICT
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    AssertPtrReturnVoid(pThis);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    AssertReturnVoid(pThis->iMagic == RTSEMEVENT_MAGIC);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    ASMAtomicWriteBool(&pThis->fEverHadSignallers, true);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    RTLockValidatorRecSharedAddOwner(&pThis->Signallers, hThread, NULL);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#endif
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync}
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsyncRTDECL(void) RTSemEventRemoveSignaller(RTSEMEVENT hEventSem, RTTHREAD hThread)
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync{
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#ifdef RTSEMEVENT_STRICT
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    struct RTSEMEVENTINTERNAL *pThis = hEventSem;
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    AssertPtrReturnVoid(pThis);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    AssertReturnVoid(pThis->iMagic == RTSEMEVENT_MAGIC);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync    RTLockValidatorRecSharedRemoveOwner(&pThis->Signallers, hThread);
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync#endif
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync}
0fcf82b2591711fa8980e8f5d9cad1b8f222d6d7vboxsync
d605d5391db09e6395a1c091f148f4b86af84bd3vboxsync#endif /* glibc < 2.6 || IPRT_WITH_FUTEX_BASED_SEMS */
d605d5391db09e6395a1c091f148f4b86af84bd3vboxsync