sdk/runtime/platform/thread_win.cc

// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

#include "platform/thread.h"

#include <process.h>

#include "platform/assert.h"

namespace dart {

class ThreadStartData {
 public:
  ThreadStartData(Thread::ThreadStartFunction function, uword parameter)
      : function_(function), parameter_(parameter) {}

  Thread::ThreadStartFunction function() const { return function_; }
  uword parameter() const { return parameter_; }

 private:
  Thread::ThreadStartFunction function_;
  uword parameter_;

  DISALLOW_COPY_AND_ASSIGN(ThreadStartData);
};


// Dispatch to the thread start function provided by the caller. This trampoline
// is used to ensure that the thread is properly destroyed if the thread just
// exits.
static unsigned int __stdcall ThreadEntry(void* data_ptr) {
  ThreadStartData* data =  reinterpret_cast<ThreadStartData*>(data_ptr);

  Thread::ThreadStartFunction function = data->function();
  uword parameter = data->parameter();
  delete data;

  // Call the supplied thread start function handing it its parameters.
  function(parameter);

  // When the function returns here close the handle.
  CloseHandle(GetCurrentThread());

  return 0;
}


int Thread::Start(ThreadStartFunction function, uword parameter) {
  ThreadStartData* start_data = new ThreadStartData(function, parameter);
  uint32_t tid;
  uintptr_t thread =
      _beginthreadex(NULL, 64 * KB, ThreadEntry, start_data, 0, &tid);
  if (thread == -1L || thread == 0) {
#ifdef DEBUG
    fprintf(stderr, "_beginthreadex error: %d (%s)\n", errno, strerror(errno));
#endif
    return errno;
  }

  return 0;
}


ThreadLocalKey Thread::kUnsetThreadLocalKey = TLS_OUT_OF_INDEXES;


ThreadLocalKey Thread::CreateThreadLocal() {
  ThreadLocalKey key = TlsAlloc();
  if (key == kUnsetThreadLocalKey) {
    FATAL("TlsAlloc failed");
  }
  return key;
}


void Thread::DeleteThreadLocal(ThreadLocalKey key) {
  ASSERT(key != kUnsetThreadLocalKey);
  BOOL result = TlsFree(key);
  if (!result) {
    FATAL("TlsFree failed");
  }
}


void Thread::SetThreadLocal(ThreadLocalKey key, uword value) {
  ASSERT(key != kUnsetThreadLocalKey);
  BOOL result = TlsSetValue(key, reinterpret_cast<void*>(value));
  if (!result) {
    FATAL("TlsSetValue failed");
  }
}


Mutex::Mutex() {
  // Allocate unnamed semaphore with initial count 1 and max count 1.
  data_.semaphore_ = CreateSemaphore(NULL, 1, 1, NULL);
  if (data_.semaphore_ == NULL) {
    FATAL("Mutex allocation failed");
  }
}


Mutex::~Mutex() {
  CloseHandle(data_.semaphore_);
}


void Mutex::Lock() {
  DWORD result = WaitForSingleObject(data_.semaphore_, INFINITE);
  if (result != WAIT_OBJECT_0) {
    FATAL("Mutex lock failed");
  }
}


bool Mutex::TryLock() {
  // Attempt to pass the semaphore but return immediately.
  DWORD result = WaitForSingleObject(data_.semaphore_, 0);
  if (result == WAIT_OBJECT_0) {
    return true;
  }
  if (result == WAIT_ABANDONED || result == WAIT_FAILED) {
    FATAL("Mutex try lock failed");
  }
  ASSERT(result == WAIT_TIMEOUT);
  return false;
}


void Mutex::Unlock() {
  BOOL result = ReleaseSemaphore(data_.semaphore_, 1, NULL);
  if (result == 0) {
    FATAL("Mutex unlock failed");
  }
}


Monitor::Monitor() {
  InitializeCriticalSection(&data_.cs_);
  // Create auto-reset event used to implement Notify. Auto-reset
  // events only wake one thread waiting for them on SetEvent.
  data_.notify_event_ = CreateEvent(NULL, FALSE, FALSE, NULL);
  // Create manual-reset event used to implement
  // NotifyAll. Manual-reset events wake all threads waiting for them
  // on SetEvent.
  data_.notify_all_event_ = CreateEvent(NULL, TRUE, FALSE, NULL);
  if ((data_.notify_event_ == NULL) || (data_.notify_all_event_ == NULL)) {
    FATAL("Failed allocating event object for monitor");
  }
  InitializeCriticalSection(&data_.waiters_cs_);
  data_.waiters_ = 0;
}


Monitor::~Monitor() {
  DeleteCriticalSection(&data_.cs_);
  CloseHandle(data_.notify_event_);
  CloseHandle(data_.notify_all_event_);
  DeleteCriticalSection(&data_.waiters_cs_);
}


void Monitor::Enter() {
  EnterCriticalSection(&data_.cs_);
}


void Monitor::Exit() {
  LeaveCriticalSection(&data_.cs_);
}


Monitor::WaitResult Monitor::Wait(int64_t millis) {
  Monitor::WaitResult retval = kNotified;

  // Record the fact that we will start waiting. This is used to only
  // reset the notify all event when all waiting threads have dealt
  // with the event.
  EnterCriticalSection(&data_.waiters_cs_);
  data_.waiters_++;
  LeaveCriticalSection(&data_.waiters_cs_);

  // Leave the monitor critical section while waiting.
  LeaveCriticalSection(&data_.cs_);

  // Perform the actual wait using wait for multiple objects on both
  // the notify and the notify all events.
  static const intptr_t kNotifyEventIndex = 0;
  static const intptr_t kNotifyAllEventIndex = 1;
  static const intptr_t kNumberOfEvents = 2;
  HANDLE events[kNumberOfEvents];
  events[kNotifyEventIndex] = data_.notify_event_;
  events[kNotifyAllEventIndex] = data_.notify_all_event_;

  DWORD result = WAIT_FAILED;
  if (millis == 0) {
    // Wait forever for a Notify or a NotifyAll event.
    result = WaitForMultipleObjects(2, events, FALSE, INFINITE);
    if (result == WAIT_FAILED) {
      FATAL("Monitor::Wait failed");
    }
  } else {
    // Wait for the given period of time for a Notify or a NotifyAll
    // event.
    result = WaitForMultipleObjects(2, events, FALSE, millis);
    if (result == WAIT_FAILED) {
      FATAL("Monitor::Wait with timeout failed");
    }
    if (result == WAIT_TIMEOUT) {
      retval = kTimedOut;
    }
  }

  // Check if we are the last waiter on a notify all. If we are, reset
  // the notify all event.
  EnterCriticalSection(&data_.waiters_cs_);
  data_.waiters_--;
  if ((data_.waiters_ == 0) &&
      (result == (WAIT_OBJECT_0 + kNotifyAllEventIndex))) {
    ResetEvent(data_.notify_all_event_);
  }
  LeaveCriticalSection(&data_.waiters_cs_);

  // Reacquire the monitor critical section before continuing.
  EnterCriticalSection(&data_.cs_);

  return retval;
}


void Monitor::Notify() {
  // Signal one waiter through the notify auto-reset event if there
  // are any waiters.
  EnterCriticalSection(&data_.waiters_cs_);
  if (data_.waiters_ > 0) {
    SetEvent(data_.notify_event_);
  }
  LeaveCriticalSection(&data_.waiters_cs_);
}


void Monitor::NotifyAll() {
  // Signal all waiters through the notify all manual-reset event if
  // there are any waiters.
  EnterCriticalSection(&data_.waiters_cs_);
  if (data_.waiters_ > 0) {
    SetEvent(data_.notify_all_event_);
  }
  LeaveCriticalSection(&data_.waiters_cs_);
}

}  // namespace dart