Initial Android Auto External View Systems drivers

Add support for EVS system camera and display drivers.
These build and run but still contain significant placeholder code and
TODO items.

Bug: 32095143
Test:  run against evs_test (submitted in future change set)
Change-Id: I9187e888f03248e5cd43293253dc76a71184c02d
diff --git a/evs/1.0/default/EvsEnumerator.cpp b/evs/1.0/default/EvsEnumerator.cpp
new file mode 100644
index 0000000..9f38041
--- /dev/null
+++ b/evs/1.0/default/EvsEnumerator.cpp
@@ -0,0 +1,161 @@
+/*
+ * Copyright (C) 2016 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 "android.hardware.evs@1.0-service"
+
+#include "EvsEnumerator.h"
+#include "EvsCamera.h"
+#include "EvsDisplay.h"
+
+namespace android {
+namespace hardware {
+namespace evs {
+namespace V1_0 {
+namespace implementation {
+
+
+EvsEnumerator::EvsEnumerator() {
+    ALOGD("EvsEnumerator created");
+
+    // Add sample camera data to our list of cameras
+    // NOTE:  The id strings trigger special initialization inside the EvsCamera constructor
+    mCameraList.emplace_back( new EvsCamera(EvsCamera::kCameraName_Backup),    false );
+    mCameraList.emplace_back( new EvsCamera("LaneView"),                       false );
+    mCameraList.emplace_back( new EvsCamera(EvsCamera::kCameraName_RightTurn), false );
+}
+
+// Methods from ::android::hardware::evs::V1_0::IEvsEnumerator follow.
+Return<void> EvsEnumerator::getCameraList(getCameraList_cb _hidl_cb)  {
+    ALOGD("getCameraList");
+
+    const unsigned numCameras = mCameraList.size();
+
+    // Build up a packed array of CameraDesc for return
+    // NOTE:  Only has to live until the callback returns
+    std::vector<CameraDesc> descriptions;
+    descriptions.reserve(numCameras);
+    for (const auto& cam : mCameraList) {
+        descriptions.push_back( cam.pCamera->getDesc() );
+    }
+
+    // Encapsulate our camera descriptions in the HIDL vec type
+    hidl_vec<CameraDesc> hidlCameras(descriptions);
+
+    // Send back the results
+    ALOGD("reporting %zu cameras available", hidlCameras.size());
+    _hidl_cb(hidlCameras);
+
+    // HIDL convention says we return Void if we sent our result back via callback
+    return Void();
+}
+
+Return<void> EvsEnumerator::openCamera(const hidl_string& cameraId,
+                                             openCamera_cb callback) {
+    ALOGD("openCamera");
+
+    // Find the named camera
+    CameraRecord *pRecord = nullptr;
+    for (auto &&cam : mCameraList) {
+        if (cam.pCamera->getDesc().cameraId == cameraId) {
+            // Found a match!
+            pRecord = &cam;
+            break;
+        }
+    }
+
+    if (!pRecord) {
+        ALOGE("Requested camera %s not found", cameraId.c_str());
+        callback(nullptr);
+    }
+    else if (pRecord->inUse) {
+        ALOGE("Cannot open camera %s which is already in use", cameraId.c_str());
+        callback(nullptr);
+    }
+    else {
+        /* TODO(b/33492405):  Do this, When HIDL can give us back a recognizable pointer
+        pRecord->inUse = true;
+         */
+        callback(pRecord->pCamera);
+    }
+
+    return Void();
+}
+
+Return<void> EvsEnumerator::closeCamera(const ::android::sp<IEvsCamera>& camera) {
+    ALOGD("closeCamera");
+
+    if (camera == nullptr) {
+        ALOGE("Ignoring call to closeCamera with null camera pointer");
+    }
+    else {
+        // Make sure the camera has stopped streaming
+        camera->stopVideoStream();
+
+        /* TODO(b/33492405):  Do this, When HIDL can give us back a recognizable pointer
+        pRecord->inUse = false;
+         */
+    }
+
+    return Void();
+}
+
+Return<void> EvsEnumerator::openDisplay(openDisplay_cb callback) {
+    ALOGD("openDisplay");
+
+    // If we already have a display active, then this request must be denied
+    if (mActiveDisplay != nullptr) {
+        ALOGW("Rejecting openDisplay request the display is already in use.");
+        callback(nullptr);
+    }
+    else {
+        // Create a new display interface and return it
+        mActiveDisplay = new EvsDisplay();
+        ALOGD("Returning new EvsDisplay object %p", mActiveDisplay.get());
+        callback(mActiveDisplay);
+    }
+
+    return Void();
+}
+
+Return<void> EvsEnumerator::closeDisplay(const ::android::sp<IEvsDisplay>& display) {
+    ALOGD("closeDisplay");
+
+    if (mActiveDisplay == nullptr) {
+        ALOGE("Ignoring closeDisplay when display is not active");
+    }
+    else if (display == nullptr) {
+        ALOGE("Ignoring closeDisplay with null display pointer");
+    }
+    else {
+        // Drop the active display
+        // TODO(b/33492405):  When HIDL provides recognizable pointers, add validation here.
+        mActiveDisplay = nullptr;
+    }
+
+    return Void();
+}
+
+
+// TODO(b/31632518):  Need to get notification when our client dies so we can close the camera.
+// As possible work around would be to give the client a HIDL object to exclusively hold
+// and use it's destructor to perform some work in the server side.
+
+
+} // namespace implementation
+} // namespace V1_0
+} // namespace evs
+} // namespace hardware
+} // namespace android