Add a privileged API for capturing and consuming bugreports

The API is mostly implemented; except for hooking up the listener
and handling an already running bugreport.

BugreportManager is the handle to the new API exposed to apps.

Generating bugreports requires root privileges. To limit the footprint
of the root access, the actual bugreport generation in Dumpstate binary,
is accessed as a oneshot service and dies after it finishes
running.

System server accesses Dumpstate via a binder interface since it does
not have root privileges.

Starting a oneshot service is done via setting a system property, which
needs to be done from system server. BugreportManagerService is the
new system server service that does this. BugreportManager calls into
BugreportManagerService via a binder interface, since the former is in
the app's process.

Both app to system server as well as system server to native service
calls are via implementations of IDumpstate binder interface.

Bug: 111441001
Test: builds. Flashed & verified it boots.
Test: wrote a test client (not included) and verified invoking
startBugreport works.

Change-Id: I4abeb753388c055c36ae0dd916af1ec8d40b7bf0
Merged-In: I4abeb753388c055c36ae0dd916af1ec8d40b7bf0
diff --git a/core/java/android/os/BugreportManager.java b/core/java/android/os/BugreportManager.java
new file mode 100644
index 0000000..1343d24
--- /dev/null
+++ b/core/java/android/os/BugreportManager.java
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+package android.os;
+
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.RequiresPermission;
+import android.annotation.SystemService;
+import android.content.Context;
+import android.os.IBinder.DeathRecipient;
+
+import java.io.FileDescriptor;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/**
+ * Class that provides a privileged API to capture and consume bugreports.
+ *
+ * @hide
+ */
+// TODO: Expose API when the implementation is more complete.
+// @SystemApi
+@SystemService(Context.BUGREPORT_SERVICE)
+public class BugreportManager {
+    private final Context mContext;
+    private final IDumpstate mBinder;
+
+    /** @hide */
+    public BugreportManager(@NonNull Context context, IDumpstate binder) {
+        mContext = context;
+        mBinder = binder;
+    }
+
+    /**
+     * An interface describing the listener for bugreport progress and status.
+     */
+    public interface BugreportListener {
+        /**
+         * Called when there is a progress update.
+         * @param progress the progress in [0.0, 100.0]
+         */
+        void onProgress(float progress);
+
+        @Retention(RetentionPolicy.SOURCE)
+        @IntDef(prefix = { "BUGREPORT_ERROR_" }, value = {
+                BUGREPORT_ERROR_INVALID_INPUT,
+                BUGREPORT_ERROR_RUNTIME
+        })
+
+        /** Possible error codes taking a bugreport can encounter */
+        @interface BugreportErrorCode {}
+
+        /** The input options were invalid */
+        int BUGREPORT_ERROR_INVALID_INPUT = 1;
+
+        /** A runtime error occured */
+        int BUGREPORT_ERROR_RUNTIME = 2;
+
+        /**
+         * Called when taking bugreport resulted in an error.
+         *
+         * @param errorCode the error that occurred. Possible values are
+         *     {@code BUGREPORT_ERROR_INVALID_INPUT}, {@code BUGREPORT_ERROR_RUNTIME}.
+         */
+        void onError(@BugreportErrorCode int errorCode);
+
+        /**
+         * Called when taking bugreport finishes successfully
+         *
+         * @param durationMs time capturing bugreport took in milliseconds
+         * @param title title for the bugreport; helpful in reminding the user why they took it
+         * @param description detailed description for the bugreport
+         */
+        void onFinished(long durationMs, @NonNull String title,
+                @NonNull String description);
+    }
+
+    /**
+     * Starts a bugreport asynchronously.
+     *
+     * @param bugreportFd file to write the bugreport. This should be opened in write-only,
+     *     append mode.
+     * @param screenshotFd file to write the screenshot, if necessary. This should be opened
+     *     in write-only, append mode.
+     * @param params options that specify what kind of a bugreport should be taken
+     * @param listener callback for progress and status updates
+     */
+    @RequiresPermission(android.Manifest.permission.DUMP)
+    public void startBugreport(@NonNull FileDescriptor bugreportFd,
+            @Nullable FileDescriptor screenshotFd,
+            @NonNull BugreportParams params, @Nullable BugreportListener listener) {
+        // TODO(b/111441001): Enforce android.Manifest.permission.DUMP if necessary.
+        DumpstateListener dsListener = new DumpstateListener(listener);
+
+        try {
+            mBinder.startBugreport(bugreportFd, screenshotFd, params.getMode(), dsListener);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+
+    // TODO(b/111441001) Connect up with BugreportListener methods.
+    private final class DumpstateListener extends IDumpstateListener.Stub
+            implements DeathRecipient {
+        private final BugreportListener mListener;
+
+        DumpstateListener(@Nullable BugreportListener listener) {
+            mListener = listener;
+        }
+
+        @Override
+        public void binderDied() {
+            // TODO(b/111441001): implement
+        }
+
+        @Override
+        public void onProgressUpdated(int progress) throws RemoteException {
+            // TODO(b/111441001): implement
+        }
+
+        @Override
+        public void onMaxProgressUpdated(int maxProgress) throws RemoteException {
+            // TODO(b/111441001): implement
+        }
+
+        @Override
+        public void onSectionComplete(String title, int status, int size, int durationMs)
+                throws RemoteException {
+            // TODO(b/111441001): implement
+        }
+    }
+}