Add chrome to the repository.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@15 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 140 insertions, 0 deletions

diff --git a/chrome/common/worker_thread_ticker.cc b/chrome/common/worker_thread_ticker.cc
new file mode 100644
index 0000000..282a0c3
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+++ b/chrome/common/worker_thread_ticker.cc
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+// Copyright 2008, Google Inc.
+// All rights reserved.
+//
+// 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 Google Inc. 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 COPYRIGHT HOLDERS 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 COPYRIGHT
+// OWNER OR 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 <algorithm>
+#include "base/logging.h"
+#include "chrome/common/worker_thread_ticker.h"
+
+WorkerThreadTicker::WorkerThreadTicker(int tick_interval)
+    : tick_interval_(tick_interval),
+      wait_handle_(NULL) {
+}
+
+WorkerThreadTicker::~WorkerThreadTicker() {
+  Stop();
+}
+
+bool WorkerThreadTicker::RegisterTickHandler(Callback *tick_handler) {
+  DCHECK(tick_handler);
+  AutoLock lock(tick_handler_list_lock_);
+  // You cannot change the list of handlers when the timer is running.
+  // You need to call Stop first.
+  if (IsRunning()) {
+    return false;
+  }
+  tick_handler_list_.push_back(tick_handler);
+  return true;
+}
+
+bool WorkerThreadTicker::UnregisterTickHandler(Callback *tick_handler) {
+  DCHECK(tick_handler);
+  AutoLock lock(tick_handler_list_lock_);
+  // You cannot change the list of handlers when the timer is running.
+  // You need to call Stop first.
+  if (IsRunning()) {
+    return false;
+  }
+  TickHandlerListType::iterator index = std::remove(tick_handler_list_.begin(),
+                                                    tick_handler_list_.end(),
+                                                    tick_handler);
+  if (index == tick_handler_list_.end()) {
+    return false;
+  }
+  tick_handler_list_.erase(index, tick_handler_list_.end());
+  return true;
+}
+
+bool WorkerThreadTicker::Start() {
+  // Do this in a lock because we don't want 2 threads to
+  // call Start at the same time
+  AutoLock lock(tick_handler_list_lock_);
+  if (IsRunning()) {
+    return false;
+  }
+  bool ret = false;
+  HANDLE event = CreateEvent(NULL, FALSE, FALSE, NULL);
+  if (!event) {
+    NOTREACHED();
+  } else {
+    if (!RegisterWaitForSingleObject(
+            &wait_handle_,
+            event,
+            reinterpret_cast<WAITORTIMERCALLBACK>(TickCallback),
+            this,
+            tick_interval_,
+            WT_EXECUTEDEFAULT)) {
+      NOTREACHED();
+      CloseHandle(event);
+    } else {
+      dummy_event_.Attach(event);
+      ret = true;
+    }
+  }
+  return ret;
+}
+
+bool WorkerThreadTicker::Stop() {
+  // Do this in a lock because we don't want 2 threads to
+  // call Stop at the same time
+  AutoLock lock(tick_handler_list_lock_);
+  if (!IsRunning()) {
+    return false;
+  }
+  DCHECK(wait_handle_);
+
+  // Wait for the callbacks to be done. Passing
+  // INVALID_HANDLE_VALUE to UnregisterWaitEx achieves this.
+  UnregisterWaitEx(wait_handle_, INVALID_HANDLE_VALUE);
+  wait_handle_ = NULL;
+  dummy_event_.Close();
+  return true;
+}
+
+bool WorkerThreadTicker::IsRunning() const {
+  return (wait_handle_ != NULL);
+}
+
+void WorkerThreadTicker::InvokeHandlers() {
+  // When the ticker is running, the handler list CANNOT be modified.
+  // So we can do the enumeration safely without a lock
+  TickHandlerListType::iterator index = tick_handler_list_.begin();
+  while (index != tick_handler_list_.end()) {
+    (*index)->OnTick();
+    index++;
+  }
+}
+
+void CALLBACK WorkerThreadTicker::TickCallback(WorkerThreadTicker* this_ticker,
+                                               BOOLEAN timer_or_wait_fired) {
+  DCHECK(NULL != this_ticker);
+  if (NULL != this_ticker) {
+    this_ticker->InvokeHandlers();
+  }
+}
+