[DisplayEventDispatcher] Move DisplayEventDispatcher into libgui.
Original source file was at frameworks/base/libs/androidfw.
For now, libgui will be its new home so that the graphics module can
depend on libandroidfw without pulling in libgui.
Bug: 142760698
Test: builds
Change-Id: Iea51e24ffb11a6ad79ad91a9e887f5e326705f1b
diff --git a/libs/gui/DisplayEventDispatcher.cpp b/libs/gui/DisplayEventDispatcher.cpp
new file mode 100644
index 0000000..54f383e
--- /dev/null
+++ b/libs/gui/DisplayEventDispatcher.cpp
@@ -0,0 +1,156 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "DisplayEventDispatcher"
+
+#include <cinttypes>
+#include <cstdint>
+
+#include <gui/DisplayEventDispatcher.h>
+#include <gui/DisplayEventReceiver.h>
+#include <utils/Log.h>
+#include <utils/Looper.h>
+
+#include <utils/Timers.h>
+
+namespace android {
+
+// Number of events to read at a time from the DisplayEventDispatcher pipe.
+// The value should be large enough that we can quickly drain the pipe
+// using just a few large reads.
+static const size_t EVENT_BUFFER_SIZE = 100;
+
+DisplayEventDispatcher::DisplayEventDispatcher(const sp<Looper>& looper,
+ ISurfaceComposer::VsyncSource vsyncSource,
+ ISurfaceComposer::ConfigChanged configChanged)
+ : mLooper(looper), mReceiver(vsyncSource, configChanged), mWaitingForVsync(false) {
+ ALOGV("dispatcher %p ~ Initializing display event dispatcher.", this);
+}
+
+status_t DisplayEventDispatcher::initialize() {
+ status_t result = mReceiver.initCheck();
+ if (result) {
+ ALOGW("Failed to initialize display event receiver, status=%d", result);
+ return result;
+ }
+
+ int rc = mLooper->addFd(mReceiver.getFd(), 0, Looper::EVENT_INPUT, this, NULL);
+ if (rc < 0) {
+ return UNKNOWN_ERROR;
+ }
+ return OK;
+}
+
+void DisplayEventDispatcher::dispose() {
+ ALOGV("dispatcher %p ~ Disposing display event dispatcher.", this);
+
+ if (!mReceiver.initCheck()) {
+ mLooper->removeFd(mReceiver.getFd());
+ }
+}
+
+status_t DisplayEventDispatcher::scheduleVsync() {
+ if (!mWaitingForVsync) {
+ ALOGV("dispatcher %p ~ Scheduling vsync.", this);
+
+ // Drain all pending events.
+ nsecs_t vsyncTimestamp;
+ PhysicalDisplayId vsyncDisplayId;
+ uint32_t vsyncCount;
+ if (processPendingEvents(&vsyncTimestamp, &vsyncDisplayId, &vsyncCount)) {
+ ALOGE("dispatcher %p ~ last event processed while scheduling was for %" PRId64 "", this,
+ ns2ms(static_cast<nsecs_t>(vsyncTimestamp)));
+ }
+
+ status_t status = mReceiver.requestNextVsync();
+ if (status) {
+ ALOGW("Failed to request next vsync, status=%d", status);
+ return status;
+ }
+
+ mWaitingForVsync = true;
+ }
+ return OK;
+}
+
+int DisplayEventDispatcher::handleEvent(int, int events, void*) {
+ if (events & (Looper::EVENT_ERROR | Looper::EVENT_HANGUP)) {
+ ALOGE("Display event receiver pipe was closed or an error occurred. "
+ "events=0x%x",
+ events);
+ return 0; // remove the callback
+ }
+
+ if (!(events & Looper::EVENT_INPUT)) {
+ ALOGW("Received spurious callback for unhandled poll event. "
+ "events=0x%x",
+ events);
+ return 1; // keep the callback
+ }
+
+ // Drain all pending events, keep the last vsync.
+ nsecs_t vsyncTimestamp;
+ PhysicalDisplayId vsyncDisplayId;
+ uint32_t vsyncCount;
+ if (processPendingEvents(&vsyncTimestamp, &vsyncDisplayId, &vsyncCount)) {
+ ALOGV("dispatcher %p ~ Vsync pulse: timestamp=%" PRId64
+ ", displayId=%" ANDROID_PHYSICAL_DISPLAY_ID_FORMAT ", count=%d",
+ this, ns2ms(vsyncTimestamp), vsyncDisplayId, vsyncCount);
+ mWaitingForVsync = false;
+ dispatchVsync(vsyncTimestamp, vsyncDisplayId, vsyncCount);
+ }
+
+ return 1; // keep the callback
+}
+
+bool DisplayEventDispatcher::processPendingEvents(nsecs_t* outTimestamp,
+ PhysicalDisplayId* outDisplayId,
+ uint32_t* outCount) {
+ bool gotVsync = false;
+ DisplayEventReceiver::Event buf[EVENT_BUFFER_SIZE];
+ ssize_t n;
+ while ((n = mReceiver.getEvents(buf, EVENT_BUFFER_SIZE)) > 0) {
+ ALOGV("dispatcher %p ~ Read %d events.", this, int(n));
+ for (ssize_t i = 0; i < n; i++) {
+ const DisplayEventReceiver::Event& ev = buf[i];
+ switch (ev.header.type) {
+ case DisplayEventReceiver::DISPLAY_EVENT_VSYNC:
+ // Later vsync events will just overwrite the info from earlier
+ // ones. That's fine, we only care about the most recent.
+ gotVsync = true;
+ *outTimestamp = ev.header.timestamp;
+ *outDisplayId = ev.header.displayId;
+ *outCount = ev.vsync.count;
+ break;
+ case DisplayEventReceiver::DISPLAY_EVENT_HOTPLUG:
+ dispatchHotplug(ev.header.timestamp, ev.header.displayId, ev.hotplug.connected);
+ break;
+ case DisplayEventReceiver::DISPLAY_EVENT_CONFIG_CHANGED:
+ dispatchConfigChanged(ev.header.timestamp, ev.header.displayId,
+ ev.config.configId);
+ break;
+ default:
+ ALOGW("dispatcher %p ~ ignoring unknown event type %#x", this, ev.header.type);
+ break;
+ }
+ }
+ }
+ if (n < 0) {
+ ALOGW("Failed to get events from display event dispatcher, status=%d", status_t(n));
+ }
+ return gotVsync;
+}
+} // namespace android