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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /mozglue/misc/ConditionVariable_windows.cpp
parentInitial commit. (diff)
downloadfirefox-upstream/124.0.1.tar.xz
firefox-upstream/124.0.1.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'mozglue/misc/ConditionVariable_windows.cpp')
-rw-r--r--mozglue/misc/ConditionVariable_windows.cpp98
1 files changed, 98 insertions, 0 deletions
diff --git a/mozglue/misc/ConditionVariable_windows.cpp b/mozglue/misc/ConditionVariable_windows.cpp
new file mode 100644
index 0000000000..0c0151f1d3
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+++ b/mozglue/misc/ConditionVariable_windows.cpp
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/Assertions.h"
+
+#include <float.h>
+#include <intrin.h>
+#include <stdlib.h>
+#include <windows.h>
+
+#include "mozilla/PlatformConditionVariable.h"
+#include "mozilla/PlatformMutex.h"
+#include "MutexPlatformData_windows.h"
+
+// Some versions of the Windows SDK have a bug where some interlocked functions
+// are not redefined as compiler intrinsics. Fix that for the interlocked
+// functions that are used in this file.
+#if defined(_MSC_VER) && !defined(InterlockedExchangeAdd)
+# define InterlockedExchangeAdd(addend, value) \
+ _InterlockedExchangeAdd((volatile long*)(addend), (long)(value))
+#endif
+
+#if defined(_MSC_VER) && !defined(InterlockedIncrement)
+# define InterlockedIncrement(addend) \
+ _InterlockedIncrement((volatile long*)(addend))
+#endif
+
+// Wrapper for native condition variable APIs.
+struct mozilla::detail::ConditionVariableImpl::PlatformData {
+ CONDITION_VARIABLE cv_;
+};
+
+mozilla::detail::ConditionVariableImpl::ConditionVariableImpl() {
+ InitializeConditionVariable(&platformData()->cv_);
+}
+
+void mozilla::detail::ConditionVariableImpl::notify_one() {
+ WakeConditionVariable(&platformData()->cv_);
+}
+
+void mozilla::detail::ConditionVariableImpl::notify_all() {
+ WakeAllConditionVariable(&platformData()->cv_);
+}
+
+void mozilla::detail::ConditionVariableImpl::wait(MutexImpl& lock) {
+ SRWLOCK* srwlock = &lock.platformData()->lock;
+ bool r =
+ SleepConditionVariableSRW(&platformData()->cv_, srwlock, INFINITE, 0);
+ MOZ_RELEASE_ASSERT(r);
+}
+
+mozilla::CVStatus mozilla::detail::ConditionVariableImpl::wait_for(
+ MutexImpl& lock, const mozilla::TimeDuration& rel_time) {
+ if (rel_time == mozilla::TimeDuration::Forever()) {
+ wait(lock);
+ return CVStatus::NoTimeout;
+ }
+
+ SRWLOCK* srwlock = &lock.platformData()->lock;
+
+ // Note that DWORD is unsigned, so we have to be careful to clamp at 0. If
+ // rel_time is Forever, then ToMilliseconds is +inf, which evaluates as
+ // greater than UINT32_MAX, resulting in the correct INFINITE wait. We also
+ // don't want to round sub-millisecond waits to 0, as that wastes energy (see
+ // bug 1437167 comment 6), so we instead round submillisecond waits to 1ms.
+ double msecd = rel_time.ToMilliseconds();
+ DWORD msec;
+ if (msecd < 0.0) {
+ msec = 0;
+ } else if (msecd > UINT32_MAX) {
+ msec = INFINITE;
+ } else {
+ msec = static_cast<DWORD>(msecd);
+ // Round submillisecond waits to 1ms.
+ if (msec == 0 && !rel_time.IsZero()) {
+ msec = 1;
+ }
+ }
+
+ BOOL r = SleepConditionVariableSRW(&platformData()->cv_, srwlock, msec, 0);
+ if (r) return CVStatus::NoTimeout;
+ MOZ_RELEASE_ASSERT(GetLastError() == ERROR_TIMEOUT);
+ return CVStatus::Timeout;
+}
+
+mozilla::detail::ConditionVariableImpl::~ConditionVariableImpl() {
+ // Native condition variables don't require cleanup.
+}
+
+inline mozilla::detail::ConditionVariableImpl::PlatformData*
+mozilla::detail::ConditionVariableImpl::platformData() {
+ static_assert(sizeof platformData_ >= sizeof(PlatformData),
+ "platformData_ is too small");
+ return reinterpret_cast<PlatformData*>(platformData_);
+}