1 files changed, 198 insertions, 0 deletions
diff --git a/Source/WebCore/platform/win/MainThreadSharedTimerWin.cpp b/Source/WebCore/platform/win/MainThreadSharedTimerWin.cpp
new file mode 100644
index 000000000..9a660db01
--- /dev/null
+++ b/Source/WebCore/platform/win/MainThreadSharedTimerWin.cpp
@@ -0,0 +1,198 @@
+/*
+ * Copyright (C) 2006 Apple 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:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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 "config.h"
+#include "MainThreadSharedTimer.h"
+
+#include "Page.h"
+#include "Settings.h"
+#include "WebCoreInstanceHandle.h"
+#include "Widget.h"
+#include <wtf/Assertions.h>
+#include <wtf/CurrentTime.h>
+#include <wtf/WindowsExtras.h>
+
+#include <mmsystem.h>
+
+// These aren't in winuser.h with the MSVS 2003 Platform SDK, 
+// so use default values in that case.
+#ifndef USER_TIMER_MINIMUM
+#define USER_TIMER_MINIMUM 0x0000000A
+#endif
+
+#ifndef USER_TIMER_MAXIMUM
+#define USER_TIMER_MAXIMUM 0x7FFFFFFF
+#endif
+
+#ifndef QS_RAWINPUT
+#define QS_RAWINPUT         0x0400
+#endif
+
+namespace WebCore {
+
+static UINT timerID;
+
+static HANDLE timer;
+static HWND timerWindowHandle = 0;
+const LPCWSTR kTimerWindowClassName = L"TimerWindowClass";
+
+static UINT timerFiredMessage = 0;
+static HANDLE timerQueue;
+static bool highResTimerActive;
+static bool processingCustomTimerMessage = false;
+static LONG pendingTimers;
+
+const int timerResolution = 1; // To improve timer resolution, we call timeBeginPeriod/timeEndPeriod with this value to increase timer resolution to 1ms.
+const int highResolutionThresholdMsec = 16; // Only activate high-res timer for sub-16ms timers (Windows can fire timers at 16ms intervals without changing the system resolution).
+const int stopHighResTimerInMsec = 300; // Stop high-res timer after 0.3 seconds to lessen power consumption (we don't use a smaller time since oscillating between high and low resolution breaks timer accuracy on XP).
+
+enum {
+    sharedTimerID = 1000,
+    endHighResTimerID = 1001,
+};
+
+LRESULT CALLBACK TimerWindowWndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
+{
+    if (message == WM_TIMER) {
+        if (wParam == sharedTimerID) {
+            KillTimer(timerWindowHandle, sharedTimerID);
+            MainThreadSharedTimer::singleton().fired();
+        } else if (wParam == endHighResTimerID) {
+            KillTimer(timerWindowHandle, endHighResTimerID);
+            highResTimerActive = false;
+            timeEndPeriod(timerResolution);
+        }
+    } else if (message == timerFiredMessage) {
+        InterlockedExchange(&pendingTimers, 0);
+        processingCustomTimerMessage = true;
+        MainThreadSharedTimer::singleton().fired();
+        processingCustomTimerMessage = false;
+    } else
+        return DefWindowProc(hWnd, message, wParam, lParam);
+
+    return 0;
+}
+
+static void initializeOffScreenTimerWindow()
+{
+    if (timerWindowHandle)
+        return;
+
+    WNDCLASSEX wcex;
+    memset(&wcex, 0, sizeof(WNDCLASSEX));
+    wcex.cbSize = sizeof(WNDCLASSEX);
+
+    wcex.lpfnWndProc    = TimerWindowWndProc;
+    wcex.hInstance      = WebCore::instanceHandle();
+    wcex.lpszClassName  = kTimerWindowClassName;
+    RegisterClassEx(&wcex);
+
+    timerWindowHandle = CreateWindow(kTimerWindowClassName, 0, 0,
+       CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, HWND_MESSAGE, 0, WebCore::instanceHandle(), 0);
+
+    timerFiredMessage = RegisterWindowMessage(L"com.apple.WebKit.TimerFired");
+}
+
+static void NTAPI queueTimerProc(PVOID, BOOLEAN)
+{
+    if (InterlockedIncrement(&pendingTimers) == 1)
+        PostMessage(timerWindowHandle, timerFiredMessage, 0, 0);
+}
+
+void MainThreadSharedTimer::setFireInterval(double interval)
+{
+    ASSERT(m_firedFunction);
+
+    unsigned intervalInMS;
+    interval *= 1000;
+    if (interval > USER_TIMER_MAXIMUM)
+        intervalInMS = USER_TIMER_MAXIMUM;
+    else
+        intervalInMS = static_cast<unsigned>(interval);
+
+    initializeOffScreenTimerWindow();
+    bool timerSet = false;
+
+    if (Settings::shouldUseHighResolutionTimers()) {
+        if (interval < highResolutionThresholdMsec) {
+            if (!highResTimerActive) {
+                highResTimerActive = true;
+                timeBeginPeriod(timerResolution);
+            }
+            SetTimer(timerWindowHandle, endHighResTimerID, stopHighResTimerInMsec, 0);
+        }
+
+        DWORD queueStatus = LOWORD(GetQueueStatus(QS_PAINT | QS_MOUSEBUTTON | QS_KEY | QS_RAWINPUT));
+
+        // Win32 has a tri-level queue with application messages > user input > WM_PAINT/WM_TIMER.
+
+        // If the queue doesn't contains input events, we use a higher priorty timer event posting mechanism.
+        if (!(queueStatus & (QS_MOUSEBUTTON | QS_KEY | QS_RAWINPUT))) {
+            if (intervalInMS < USER_TIMER_MINIMUM && !processingCustomTimerMessage && !(queueStatus & QS_PAINT)) {
+                // Call PostMessage immediately if the timer is already expired, unless a paint is pending.
+                // (we prioritize paints over timers)
+                if (InterlockedIncrement(&pendingTimers) == 1)
+                    PostMessage(timerWindowHandle, timerFiredMessage, 0, 0);
+                timerSet = true;
+            } else {
+                // Otherwise, delay the PostMessage via a CreateTimerQueueTimer
+                if (!timerQueue)
+                    timerQueue = CreateTimerQueue();
+                if (timer)
+                    DeleteTimerQueueTimer(timerQueue, timer, 0);
+                timerSet = CreateTimerQueueTimer(&timer, timerQueue, queueTimerProc, 0, intervalInMS, 0, WT_EXECUTEINTIMERTHREAD | WT_EXECUTEONLYONCE);
+            }
+        }
+    }
+
+    if (timerSet) {
+        if (timerID) {
+            KillTimer(timerWindowHandle, timerID);
+            timerID = 0;
+        }
+    } else {
+        timerID = SetTimer(timerWindowHandle, sharedTimerID, intervalInMS, 0);
+        timer = 0;
+    }
+}
+
+void MainThreadSharedTimer::stop()
+{
+    if (timerQueue && timer) {
+        DeleteTimerQueueTimer(timerQueue, timer, 0);
+        timer = 0;
+    }
+
+    if (timerID) {
+        KillTimer(timerWindowHandle, timerID);
+        timerID = 0;
+    }
+}
+
+void MainThreadSharedTimer::invalidate()
+{
+}
+
+}