Native Windows LevelDB port

Import native Windows LevelDB port by Hiram Chirino.

Extracted from from https://github.com/chirino/leveldb.git using
git diff dd0d562..aea83b7

1 files changed, 154 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..7cf9537937
--- /dev/null
+++ b/src/leveldb/port/port_win.cc
@@ -0,0 +1,154 @@
+// 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_(nullptr) {
+  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_ = nullptr;
+  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();
+  for(long i = 0; i < waiting_; ++i) {
+    ::ReleaseSemaphore(sem1_, 1, NULL);
+    while(waiting_ > 0) {
+      --waiting_;
+      ::WaitForSingleObject(sem2_, INFINITE);
+    }
+  }
+  wait_mtx_.Unlock();
+}
+
+AtomicPointer::AtomicPointer(void* v) {
+  Release_Store(v);
+}
+
+BOOL CALLBACK InitHandleFunction (PINIT_ONCE InitOnce, PVOID func, PVOID *lpContext) {
+  ((void (*)())func)();
+  return true;
+}
+
+void InitOnce(OnceType* once, void (*initializer)()) {
+  InitOnceExecuteOnce((PINIT_ONCE)once, InitHandleFunction, initializer, NULL);
+}
+
+void* AtomicPointer::Acquire_Load() const {
+  void * p = nullptr;
+  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;
+}
+
+}
+}