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Diffstat (limited to 'src/leveldb/port/port_win.cc')
-rw-r--r-- | src/leveldb/port/port_win.cc | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/src/leveldb/port/port_win.cc b/src/leveldb/port/port_win.cc new file mode 100644 index 0000000000..786cd6018a --- /dev/null +++ b/src/leveldb/port/port_win.cc @@ -0,0 +1,182 @@ +// 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() : + mutex_(::CreateMutex(NULL, FALSE, NULL)) { + assert(mutex_); +} + +Mutex::~Mutex() { + assert(mutex_); + ::CloseHandle(mutex_); +} + +void Mutex::Lock() { + assert(mutex_); + ::WaitForSingleObject(mutex_, INFINITE); +} + +void Mutex::Unlock() { + assert(mutex_); + ::ReleaseMutex(mutex_); +} + +void Mutex::AssertHeld() { + assert(mutex_); + assert(1); +} + +CondVar::CondVar(Mutex* mu) : + waiting_(0), + mu_(mu), + sema_(::CreateSemaphore(NULL, 0, 0x7fffffff, NULL)), + event_(::CreateEvent(NULL, FALSE, FALSE, NULL)), + broadcasted_(false){ + assert(mu_); +} + +CondVar::~CondVar() { + ::CloseHandle(sema_); + ::CloseHandle(event_); +} + +void CondVar::Wait() { + wait_mtx_.Lock(); + ++waiting_; + assert(waiting_ > 0); + wait_mtx_.Unlock(); + + ::SignalObjectAndWait(mu_->mutex_, sema_, INFINITE, FALSE); + + wait_mtx_.Lock(); + bool last = broadcasted_ && (--waiting_ == 0); + assert(waiting_ >= 0); + wait_mtx_.Unlock(); + + // we leave this function with the mutex held + if (last) + { + ::SignalObjectAndWait(event_, mu_->mutex_, INFINITE, FALSE); + } + else + { + ::WaitForSingleObject(mu_->mutex_, INFINITE); + } +} + +void CondVar::Signal() { + wait_mtx_.Lock(); + bool waiters = waiting_ > 0; + wait_mtx_.Unlock(); + + if (waiters) + { + ::ReleaseSemaphore(sema_, 1, 0); + } +} + +void CondVar::SignalAll() { + wait_mtx_.Lock(); + + broadcasted_ = (waiting_ > 0); + + if (broadcasted_) + { + // release all + ::ReleaseSemaphore(sema_, waiting_, 0); + wait_mtx_.Unlock(); + ::WaitForSingleObject(event_, INFINITE); + broadcasted_ = false; + } + else + { + wait_mtx_.Unlock(); + } +} + +AtomicPointer::AtomicPointer(void* v) { + Release_Store(v); +} + +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; +} + +enum InitializationState +{ + Uninitialized = 0, + Running = 1, + Initialized = 2 +}; + +void InitOnce(OnceType* once, void (*initializer)()) { + + assert(Uninitialized == LEVELDB_ONCE_INIT); + + InitializationState state = static_cast<InitializationState>(InterlockedCompareExchange(once, Running, Uninitialized)); + + if (state == Uninitialized) { + initializer(); + *once = Initialized; + } + + if (state == Running) { + while(*once != Initialized) { + Sleep(0); // yield + } + } + + assert(*once == Initialized); +} + +} +} |