lbrycrd/port/port_win.cc

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// LevelDB Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
//
// See port_example.h for documentation for the following types/functions.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// * Neither the name of the University of California, Berkeley nor the
// names of its contributors may be used to endorse or promote products
// derived from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
// DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
#include "port/port_win.h"
#include <windows.h>
#include <cassert>
namespace leveldb {
namespace port {
Mutex::Mutex() :
cs_(NULL) {
assert(!cs_);
cs_ = static_cast<void *>(new CRITICAL_SECTION());
::InitializeCriticalSection(static_cast<CRITICAL_SECTION *>(cs_));
assert(cs_);
}
Mutex::~Mutex() {
assert(cs_);
::DeleteCriticalSection(static_cast<CRITICAL_SECTION *>(cs_));
delete static_cast<CRITICAL_SECTION *>(cs_);
cs_ = NULL;
assert(!cs_);
}
void Mutex::Lock() {
assert(cs_);
::EnterCriticalSection(static_cast<CRITICAL_SECTION *>(cs_));
}
void Mutex::Unlock() {
assert(cs_);
::LeaveCriticalSection(static_cast<CRITICAL_SECTION *>(cs_));
}
void Mutex::AssertHeld() {
assert(cs_);
assert(1);
}
CondVar::CondVar(Mutex* mu) :
waiting_(0),
mu_(mu),
sem1_(::CreateSemaphore(NULL, 0, 10000, NULL)),
sem2_(::CreateSemaphore(NULL, 0, 10000, NULL)) {
assert(mu_);
}
CondVar::~CondVar() {
::CloseHandle(sem1_);
::CloseHandle(sem2_);
}
void CondVar::Wait() {
mu_->AssertHeld();
wait_mtx_.Lock();
++waiting_;
wait_mtx_.Unlock();
mu_->Unlock();
// initiate handshake
::WaitForSingleObject(sem1_, INFINITE);
::ReleaseSemaphore(sem2_, 1, NULL);
mu_->Lock();
}
void CondVar::Signal() {
wait_mtx_.Lock();
if (waiting_ > 0) {
--waiting_;
// finalize handshake
::ReleaseSemaphore(sem1_, 1, NULL);
::WaitForSingleObject(sem2_, INFINITE);
}
wait_mtx_.Unlock();
}
void CondVar::SignalAll() {
wait_mtx_.Lock();
::ReleaseSemaphore(sem1_, waiting_, NULL);
while(waiting_ > 0) {
--waiting_;
::WaitForSingleObject(sem2_, INFINITE);
}
wait_mtx_.Unlock();
}
AtomicPointer::AtomicPointer(void* v) {
Release_Store(v);
}
void InitOnce(OnceType* once, void (*initializer)()) {
once->InitOnce(initializer);
}
void* AtomicPointer::Acquire_Load() const {
void * p = NULL;
InterlockedExchangePointer(&p, rep_);
return p;
}
void AtomicPointer::Release_Store(void* v) {
InterlockedExchangePointer(&rep_, v);
}
void* AtomicPointer::NoBarrier_Load() const {
return rep_;
}
void AtomicPointer::NoBarrier_Store(void* v) {
rep_ = v;
}
}
}