Gamepad API support for chrome on android

content/browser/gamepad/gamepad_platform_data_fetcher_android.cc

+/*
+ * Copyright (c) 2014, NVIDIA CORPORATION. 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 NVIDIA CORPORATION 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 ``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 "base/strings/string_number_conversions.h"
+#include "base/strings/string_util.h"
+#include "base/strings/utf_string_conversions.h"
+#include "content/browser/gamepad/gamepad_platform_data_fetcher_android.h"
+#include "third_party/WebKit/public/platform/WebGamepads.h"
+
+#if defined(OS_ANDROID)
+
+namespace content {
+
+GamepadPlatformDataFetcherAndroid::GamepadPlatformDataFetcherAndroid() {
+}
+
+void GamepadPlatformDataFetcherAndroid::GetGamepadData(
+                                            blink::WebGamepads* pads, bool) {
+
+    GamepadsReader* m_gamepadsReader = GamepadsReader::GetInstance();
+
+    pads->length = m_gamepadsReader->updateGamepadsCount();
+    if (pads->length == 0)
+        return;
+
+    for (unsigned int i = 0; i < WebGamepads::itemsLengthCap; i++) {
+        bool ifDeviceConnected = m_gamepadsReader->isDeviceConnected(i);
+        if (ifDeviceConnected) {
+
+            // Set connected flag to true for all the gamepad devices that are
+            // attached.
+            pads->items[i].connected = true;
+
+            // Map the Gamepad DeviceName String to the WebGamepad Id and then
+            // convert the utf-8 id string to WebUChar.
+            // Ideally it should be mapped to vendor and product information
+            // but it is only available at kernel level and it can not be
+            // queried using class android.hardware.input.InputManager.
+
+            std::string string1 = m_gamepadsReader->getDeviceName(i);
+            base::TruncateUTF8ToByteSize(string1, WebGamepad::idLengthCap - 1,
+                                            &string1);
+            base::string16 tmp16 = base::UTF8ToUTF16(string1);
+            memset(pads->items[i].id, 0, sizeof(pads->items[i].id));
+            tmp16.copy(pads->items[i].id, arraysize(pads->items[i].id) - 1);
+
+            // timestamp is queried from GamepadReader.
+            pads->items[i].timestamp = m_gamepadsReader->getDeviceTimestamp(i);
+
+            // A float vector is queried from GamepadReader that stores the
+            // state of axeses.
+            std::vector<float> axes = m_gamepadsReader->getDeviceAxes(i);
+
+            // Set WebGamepad axeslength to total number of axes on the gamepad
+            // device.
+            pads->items[i].axesLength = axes.size();
+
+            // A float vector is queried from GamepadReader that stores the
+            // button's state.
+            std::vector<float> buttons = m_gamepadsReader->getDeviceButtons(i);
+
+            // Set WebGamepad buttonslength to total numbers of buttons on the
+            // gamepad device.
+            pads->items[i].buttonsLength = buttons.size();
+
+            // Set WebGamepad connected flag to false if buttonslength or
+            // axeslength returned by
+            // JNI are larger than permitted value.
+            if (pads->items[i].axesLength > WebGamepad::axesLengthCap ||
+                                pads->items[i].buttonsLength >
+                                                WebGamepad::buttonsLengthCap) {
+                pads->items[i].connected = false;
+            } else {
+                // Copy axes state to the WebGamepad axes[].
+                for (unsigned int j = 0; j < pads->items[i].axesLength; j++)
+                    pads->items[i].axes[j] = axes[j];
+
+                // Copy buttons state to the WebGamepad buttons[].
+                for (unsigned int j = 0; j < pads->items[i].buttonsLength; j++)
+                    pads->items[i].buttons[j] = buttons[j];
+            }
+        } else {
+            // Set connected flag to flase for all the gamepad devices that are
+            // not attached.
+            pads->items[i].connected = false;
+        }
+    }
+}
+
+void GamepadPlatformDataFetcherAndroid::PauseHint(bool isaccesspaused) {
+    GamepadsReader::GetInstance()->notifyForGamepadsAccess(isaccesspaused);
+}
+
+GamepadPlatformDataFetcherAndroid::~GamepadPlatformDataFetcherAndroid() {
+}
+
+}  // namespace content
+#endif