New IpConnectivityMetrics service
This patch defines a new metrics service for IpConnectivity events
defined in android.net.metrics, separate from currently existing
MetricsLoggerService.
Similarly to MetricsLoggerService, the new service has an event buffer.
It also implements a dumpsys interface that can be used to flush events
and output a serialized proto.
Bug: 31254800
Change-Id: I0c3faeb4008b283f85d9ba9460371fa68956ea3b
diff --git a/services/core/java/com/android/server/connectivity/IpConnectivityMetrics.java b/services/core/java/com/android/server/connectivity/IpConnectivityMetrics.java
new file mode 100644
index 0000000..8f419d8
--- /dev/null
+++ b/services/core/java/com/android/server/connectivity/IpConnectivityMetrics.java
@@ -0,0 +1,222 @@
+/*
+ * 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.
+ */
+
+package com.android.server.connectivity;
+
+import android.content.Context;
+import android.net.ConnectivityMetricsEvent;
+import android.net.IIpConnectivityMetrics;
+import android.net.metrics.IpConnectivityLog;
+import android.os.IBinder;
+import android.os.Parcelable;
+import android.text.TextUtils;
+import android.util.Base64;
+import android.util.Log;
+import com.android.internal.annotations.GuardedBy;
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.server.SystemService;
+import java.io.FileDescriptor;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.util.ArrayList;
+
+import static com.android.server.connectivity.metrics.IpConnectivityLogClass.IpConnectivityEvent;
+
+/** {@hide} */
+final public class IpConnectivityMetrics extends SystemService {
+ private static final String TAG = IpConnectivityMetrics.class.getSimpleName();
+ private static final boolean DBG = false;
+
+ private static final String SERVICE_NAME = IpConnectivityLog.SERVICE_NAME;
+
+ // Default size of the event buffer. Once the buffer is full, incoming events are dropped.
+ private static final int DEFAULT_BUFFER_SIZE = 2000;
+
+ // Lock ensuring that concurrent manipulations of the event buffer are correct.
+ // There are three concurrent operations to synchronize:
+ // - appending events to the buffer.
+ // - iterating throught the buffer.
+ // - flushing the buffer content and replacing it by a new buffer.
+ private final Object mLock = new Object();
+
+ @VisibleForTesting
+ public final Impl impl = new Impl();
+ @GuardedBy("mLock")
+ private ArrayList<ConnectivityMetricsEvent> mBuffer;
+ @GuardedBy("mLock")
+ private int mDropped;
+ @GuardedBy("mLock")
+ private int mCapacity;
+
+ public IpConnectivityMetrics(Context ctx) {
+ super(ctx);
+ initBuffer();
+ }
+
+ @Override
+ public void onStart() {
+ if (DBG) Log.d(TAG, "onStart");
+ }
+
+ @Override
+ public void onBootPhase(int phase) {
+ if (phase == SystemService.PHASE_SYSTEM_SERVICES_READY) {
+ if (DBG) Log.d(TAG, "onBootPhase");
+
+ publishBinderService(SERVICE_NAME, impl);
+ }
+ }
+
+ @VisibleForTesting
+ public int bufferCapacity() {
+ return DEFAULT_BUFFER_SIZE; // TODO: read from config
+ }
+
+ private void initBuffer() {
+ synchronized (mLock) {
+ mDropped = 0;
+ mCapacity = bufferCapacity();
+ mBuffer = new ArrayList<>(mCapacity);
+ }
+ }
+
+ private int append(ConnectivityMetricsEvent event) {
+ if (DBG) Log.d(TAG, "logEvent: " + event);
+ synchronized (mLock) {
+ final int left = mCapacity - mBuffer.size();
+ if (event == null) {
+ return left;
+ }
+ if (left == 0) {
+ mDropped++;
+ return 0;
+ }
+ mBuffer.add(event);
+ return left - 1;
+ }
+ }
+
+ private String flushEncodedOutput() {
+ final ArrayList<ConnectivityMetricsEvent> events;
+ final int dropped;
+ synchronized (mLock) {
+ events = mBuffer;
+ dropped = mDropped;
+ initBuffer();
+ }
+
+ final byte[] data;
+ try {
+ data = IpConnectivityEventBuilder.serialize(dropped, events);
+ } catch (IOException e) {
+ Log.e(TAG, "could not serialize events", e);
+ return "";
+ }
+
+ return Base64.encodeToString(data, Base64.DEFAULT);
+ }
+
+ /**
+ * Clears the event buffer and prints its content as a protobuf serialized byte array
+ * inside a base64 encoded string.
+ */
+ private void cmdFlush(FileDescriptor fd, PrintWriter pw, String[] args) {
+ pw.print(flushEncodedOutput());
+ }
+
+ /**
+ * Prints the content of the event buffer, either using the events ASCII representation
+ * or using protobuf text format.
+ */
+ private void cmdList(FileDescriptor fd, PrintWriter pw, String[] args) {
+ final ArrayList<ConnectivityMetricsEvent> events;
+ synchronized (mLock) {
+ events = new ArrayList(mBuffer);
+ }
+
+ if (args.length > 1 && args[1].equals("proto")) {
+ for (IpConnectivityEvent ev : IpConnectivityEventBuilder.toProto(events)) {
+ pw.print(ev.toString());
+ }
+ return;
+ }
+
+ for (ConnectivityMetricsEvent ev : events) {
+ pw.println(ev.toString());
+ }
+ }
+
+ private void cmdStats(FileDescriptor fd, PrintWriter pw, String[] args) {
+ synchronized (mLock) {
+ pw.println("Buffered events: " + mBuffer.size());
+ pw.println("Buffer capacity: " + mCapacity);
+ pw.println("Dropped events: " + mDropped);
+ }
+ }
+
+ private void cmdDefault(FileDescriptor fd, PrintWriter pw, String[] args) {
+ if (args.length == 0) {
+ pw.println("No command");
+ return;
+ }
+ pw.println("Unknown command " + TextUtils.join(" ", args));
+ }
+
+ public final class Impl extends IIpConnectivityMetrics.Stub {
+ static final String CMD_FLUSH = "flush";
+ static final String CMD_LIST = "list";
+ static final String CMD_STATS = "stats";
+ static final String CMD_DEFAULT = CMD_STATS;
+
+ @Override
+ public int logEvent(ConnectivityMetricsEvent event) {
+ enforceConnectivityInternalPermission();
+ return append(event);
+ }
+
+ @Override
+ public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
+ enforceDumpPermission();
+ if (DBG) Log.d(TAG, "dumpsys " + TextUtils.join(" ", args));
+ final String cmd = (args.length > 0) ? args[0] : CMD_DEFAULT;
+ switch (cmd) {
+ case CMD_FLUSH:
+ cmdFlush(fd, pw, args);
+ return;
+ case CMD_LIST:
+ cmdList(fd, pw, args);
+ return;
+ case CMD_STATS:
+ cmdStats(fd, pw, args);
+ return;
+ default:
+ cmdDefault(fd, pw, args);
+ }
+ }
+
+ private void enforceConnectivityInternalPermission() {
+ enforcePermission(android.Manifest.permission.CONNECTIVITY_INTERNAL);
+ }
+
+ private void enforceDumpPermission() {
+ enforcePermission(android.Manifest.permission.DUMP);
+ }
+
+ private void enforcePermission(String what) {
+ getContext().enforceCallingOrSelfPermission(what, "IpConnectivityMetrics");
+ }
+ };
+}