content: /*
   * Copyright (C) 2006 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.content;
  
  import android.annotation.UnsupportedAppUsage;
  import android.app.ActivityManager;
  import android.app.ActivityThread;
  import android.app.IActivityManager;
  import android.app.QueuedWork;
  import android.os.Build;
  import android.os.Bundle;
  import android.os.IBinder;
  import android.os.RemoteException;
  import android.util.Log;
  import android.util.Slog;
  
  /**
   * Base class for code that receives and handles broadcast intents sent by
   * {@link android.content.Context#sendBroadcast(Intent)}.
   *
   * <p>You can either dynamically register an instance of this class with
   * {@link Context#registerReceiver Context.registerReceiver()}
   * or statically declare an implementation with the
   * {@link android.R.styleable#AndroidManifestReceiver &lt;receiver&gt;}
   * tag in your <code>AndroidManifest.xml</code>.
   *
   * <div class="special reference">
   * <h3>Developer Guides</h3>
   * <p>For more information about using BroadcastReceiver, read the
   * <a href="{@docRoot}guide/components/broadcasts.html">Broadcasts</a> developer guide.</p></div>
   *
   */
  public abstract class BroadcastReceiver {
      @UnsupportedAppUsage
      private PendingResult mPendingResult;
      private boolean mDebugUnregister;
  
      /**
       * State for a result that is pending for a broadcast receiver.  Returned
       * by {@link BroadcastReceiver#goAsync() goAsync()}
       * while in {@link BroadcastReceiver#onReceive BroadcastReceiver.onReceive()}.
       * This allows you to return from onReceive() without having the broadcast
       * terminate; you must call {@link #finish()} once you are done with the
       * broadcast.  This allows you to process the broadcast off of the main
       * thread of your app.
       *
       * <p>Note on threading: the state inside of this class is not itself
       * thread-safe, however you can use it from any thread if you properly
       * sure that you do not have races.  Typically this means you will hand
       * the entire object to another thread, which will be solely responsible
       * for setting any results and finally calling {@link #finish()}.
       */
      public static class PendingResult {
          /** @hide */
          public static final int TYPE_COMPONENT = 0;
          /** @hide */
          public static final int TYPE_REGISTERED = 1;
          /** @hide */
          public static final int TYPE_UNREGISTERED = 2;
  
          @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
          final int mType;
          @UnsupportedAppUsage
          final boolean mOrderedHint;
          @UnsupportedAppUsage
          final boolean mInitialStickyHint;
          @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
          final IBinder mToken;
          @UnsupportedAppUsage
          final int mSendingUser;
          @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
          final int mFlags;
  
          @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
          int mResultCode;
          @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
          String mResultData;
          @UnsupportedAppUsage
          Bundle mResultExtras;
          @UnsupportedAppUsage
          boolean mAbortBroadcast;
          @UnsupportedAppUsage
          boolean mFinished;
  
          /** @hide */
          @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
          public PendingResult(int resultCode, String resultData, Bundle resultExtras, int type,
                  boolean ordered, boolean sticky, IBinder token, int userId, int flags) {
              mResultCode = resultCode;
              mResultData = resultData;
              mResultExtras = resultExtras;
              mType = type;
              mOrderedHint = ordered;
              mInitialStickyHint = sticky;
              mToken = token;
              mSendingUser = userId;
              mFlags = flags;
          }
  
          /**
           * Version of {@link BroadcastReceiver#setResultCode(int)
           * BroadcastReceiver.setResultCode(int)} for
           * asynchronous broadcast handling.
           */
          public final void setResultCode(int code) {
              checkSynchronousHint();
              mResultCode = code;
          }
  
          /**
           * Version of {@link BroadcastReceiver#getResultCode()
           * BroadcastReceiver.getResultCode()} for
           * asynchronous broadcast handling.
           */
          public final int getResultCode() {
              return mResultCode;
          }
  
          /**
           * Version of {@link BroadcastReceiver#setResultData(String)
           * BroadcastReceiver.setResultData(String)} for
           * asynchronous broadcast handling.
           */
          public final void setResultData(String data) {
              checkSynchronousHint();
              mResultData = data;
          }
  
          /**
           * Version of {@link BroadcastReceiver#getResultData()
           * BroadcastReceiver.getResultData()} for
           * asynchronous broadcast handling.
           */
          public final String getResultData() {
              return mResultData;
          }
  
          /**
           * Version of {@link BroadcastReceiver#setResultExtras(Bundle)
           * BroadcastReceiver.setResultExtras(Bundle)} for
           * asynchronous broadcast handling.
           */
          public final void setResultExtras(Bundle extras) {
              checkSynchronousHint();
              mResultExtras = extras;
          }
  
          /**
           * Version of {@link BroadcastReceiver#getResultExtras(boolean)
           * BroadcastReceiver.getResultExtras(boolean)} for
           * asynchronous broadcast handling.
           */
          public final Bundle getResultExtras(boolean makeMap) {
              Bundle e = mResultExtras;
              if (!makeMap) return e;
              if (e == null) mResultExtras = e = new Bundle();
              return e;
          }
  
          /**
           * Version of {@link BroadcastReceiver#setResult(int, String, Bundle)
           * BroadcastReceiver.setResult(int, String, Bundle)} for
           * asynchronous broadcast handling.
           */
          public final void setResult(int code, String data, Bundle extras) {
              checkSynchronousHint();
              mResultCode = code;
              mResultData = data;
              mResultExtras = extras;
          }
  
          /**
           * Version of {@link BroadcastReceiver#getAbortBroadcast()
           * BroadcastReceiver.getAbortBroadcast()} for
           * asynchronous broadcast handling.
           */
          public final boolean getAbortBroadcast() {
              return mAbortBroadcast;
          }
  
          /**
           * Version of {@link BroadcastReceiver#abortBroadcast()
           * BroadcastReceiver.abortBroadcast()} for
           * asynchronous broadcast handling.
           */
          public final void abortBroadcast() {
              checkSynchronousHint();
              mAbortBroadcast = true;
          }
  
          /**
           * Version of {@link BroadcastReceiver#clearAbortBroadcast()
           * BroadcastReceiver.clearAbortBroadcast()} for
           * asynchronous broadcast handling.
           */
          public final void clearAbortBroadcast() {
              mAbortBroadcast = false;
          }
  
          /**
           * Finish the broadcast.  The current result will be sent and the
           * next broadcast will proceed.
           */
          public final void finish() {
              if (mType == TYPE_COMPONENT) {
                  final IActivityManager mgr = ActivityManager.getService();
                  if (QueuedWork.hasPendingWork()) {
                      // If this is a broadcast component, we need to make sure any
                      // queued work is complete before telling AM we are done, so
                      // we don't have our process killed before that.  We now know
                      // there is pending work; put another piece of work at the end
                      // of the list to finish the broadcast, so we don't block this
                      // thread (which may be the main thread) to have it finished.
                      //
                      // Note that we don't need to use QueuedWork.addFinisher() with the
                      // runnable, since we know the AM is waiting for us until the
                      // executor gets to it.
                      QueuedWork.queue(new Runnable() {
                          @Override public void run() {
                              if (ActivityThread.DEBUG_BROADCAST) Slog.i(ActivityThread.TAG,
                                      "Finishing broadcast after work to component " + mToken);
                              sendFinished(mgr);
                          }
                      }, false);
                  } else {
                      if (ActivityThread.DEBUG_BROADCAST) Slog.i(ActivityThread.TAG,
                              "Finishing broadcast to component " + mToken);
                      sendFinished(mgr);
                  }
              } else if (mOrderedHint && mType != TYPE_UNREGISTERED) {
                  if (ActivityThread.DEBUG_BROADCAST) Slog.i(ActivityThread.TAG,
                          "Finishing broadcast to " + mToken);
                  final IActivityManager mgr = ActivityManager.getService();
                  sendFinished(mgr);
              }
          }
  
          /** @hide */
          public void setExtrasClassLoader(ClassLoader cl) {
              if (mResultExtras != null) {
                  mResultExtras.setClassLoader(cl);
              }
          }
  
          /** @hide */
          public void sendFinished(IActivityManager am) {
              synchronized (this) {
                  if (mFinished) {
                      throw new IllegalStateException("Broadcast already finished");
                  }
                  mFinished = true;
  
                  try {
                      if (mResultExtras != null) {
                          mResultExtras.setAllowFds(false);
                      }
                      if (mOrderedHint) {
                          am.finishReceiver(mToken, mResultCode, mResultData, mResultExtras,
                                  mAbortBroadcast, mFlags);
                      } else {
                          // This broadcast was sent to a component; it is not ordered,
                          // but we still need to tell the activity manager we are done.
                          am.finishReceiver(mToken, 0, null, null, false, mFlags);
                      }
                  } catch (RemoteException ex) {
                  }
              }
          }
  
          /** @hide */
          public int getSendingUserId() {
              return mSendingUser;
          }
  
          void checkSynchronousHint() {
              // Note that we don't assert when receiving the initial sticky value,
              // since that may have come from an ordered broadcast.  We'll catch
              // them later when the real broadcast happens again.
              if (mOrderedHint || mInitialStickyHint) {
                  return;
              }
              RuntimeException e = new RuntimeException(
                      "BroadcastReceiver trying to return result during a non-ordered broadcast");
              e.fillInStackTrace();
              Log.e("BroadcastReceiver", e.getMessage(), e);
          }
      }
  
      public BroadcastReceiver() {
      }
  
      /**
       * This method is called when the BroadcastReceiver is receiving an Intent
       * broadcast.  During this time you can use the other methods on
       * BroadcastReceiver to view/modify the current result values.  This method
       * is always called within the main thread of its process, unless you
       * explicitly asked for it to be scheduled on a different thread using
       * {@link android.content.Context#registerReceiver(BroadcastReceiver,
       * IntentFilter, String, android.os.Handler)}. When it runs on the main
       * thread you should
       * never perform long-running operations in it (there is a timeout of
       * 10 seconds that the system allows before considering the receiver to
       * be blocked and a candidate to be killed). You cannot launch a popup dialog
       * in your implementation of onReceive().
       *
       * <p><b>If this BroadcastReceiver was launched through a &lt;receiver&gt; tag,
       * then the object is no longer alive after returning from this
       * function.</b> This means you should not perform any operations that
       * return a result to you asynchronously. If you need to perform any follow up
       * background work, schedule a {@link android.app.job.JobService} with
       * {@link android.app.job.JobScheduler}.
       *
       * If you wish to interact with a service that is already running and previously
       * bound using {@link android.content.Context#bindService(Intent, ServiceConnection, int) bindService()},
       * you can use {@link #peekService}.
       *
       * <p>The Intent filters used in {@link android.content.Context#registerReceiver}
       * and in application manifests are <em>not</em> guaranteed to be exclusive. They
       * are hints to the operating system about how to find suitable recipients. It is
       * possible for senders to force delivery to specific recipients, bypassing filter
       * resolution.  For this reason, {@link #onReceive(Context, Intent) onReceive()}
       * implementations should respond only to known actions, ignoring any unexpected
       * Intents that they may receive.
       *
       * @param context The Context in which the receiver is running.
       * @param intent The Intent being received.
       */
      public abstract void onReceive(Context context, Intent intent);
  
      /**
       * This can be called by an application in {@link #onReceive} to allow
       * it to keep the broadcast active after returning from that function.
       * This does <em>not</em> change the expectation of being relatively
       * responsive to the broadcast, but does allow
       * the implementation to move work related to it over to another thread
       * to avoid glitching the main UI thread due to disk IO.
       *
       * <p>As a general rule, broadcast receivers are allowed to run for up to 10 seconds
       * before they system will consider them non-responsive and ANR the app.  Since these usually
       * execute on the app's main thread, they are already bound by the ~5 second time limit
       * of various operations that can happen there (not to mention just avoiding UI jank), so
       * the receive limit is generally not of concern.  However, once you use {@code goAsync}, though
       * able to be off the main thread, the broadcast execution limit still applies, and that
       * includes the time spent between calling this method and ultimately
       * {@link PendingResult#finish() PendingResult.finish()}.</p>
       *
       * <p>If you are taking advantage of this method to have more time to execute, it is useful
       * to know that the available time can be longer in certain situations.  In particular, if
       * the broadcast you are receiving is not a foreground broadcast (that is, the sender has not
       * used {@link Intent#FLAG_RECEIVER_FOREGROUND}), then more time is allowed for the receivers
       * to run, allowing them to execute for 30 seconds or even a bit more.  This is something that
       * receivers should rarely take advantage of (long work should be punted to another system
       * facility such as {@link android.app.job.JobScheduler}, {@link android.app.Service}, or
       * see especially {@link android.support.v4.app.JobIntentService}), but can be useful in
       * certain rare cases where it is necessary to do some work as soon as the broadcast is
       * delivered.  Keep in mind that the work you do here will block further broadcasts until
       * it completes, so taking advantage of this at all excessively can be counter-productive
       * and cause later events to be received more slowly.</p>
       *
       * @return Returns a {@link PendingResult} representing the result of
       * the active broadcast.  The BroadcastRecord itself is no longer active;
       * all data and other interaction must go through {@link PendingResult}
       * APIs.  The {@link PendingResult#finish PendingResult.finish()} method
       * must be called once processing of the broadcast is done.
       */
      public final PendingResult goAsync() {
          PendingResult res = mPendingResult;
          mPendingResult = null;
          return res;
      }
  
      /**
       * Provide a binder to an already-bound service.  This method is synchronous
       * and will not start the target service if it is not present, so it is safe
       * to call from {@link #onReceive}.
       *
       * For peekService() to return a non null {@link android.os.IBinder} interface
       * the service must have published it before. In other words some component
       * must have called {@link android.content.Context#bindService(Intent, ServiceConnection, int)} on it.
       *
       * @param myContext The Context that had been passed to {@link #onReceive(Context, Intent)}
       * @param service Identifies the already-bound service you wish to use. See
       * {@link android.content.Context#bindService(Intent, ServiceConnection, int)}
       * for more information.
       */
      public IBinder peekService(Context myContext, Intent service) {
          IActivityManager am = ActivityManager.getService();
          IBinder binder = null;
          try {
              service.prepareToLeaveProcess(myContext);
              binder = am.peekService(service, service.resolveTypeIfNeeded(
                      myContext.getContentResolver()), myContext.getOpPackageName());
          } catch (RemoteException e) {
          }
          return binder;
      }
  
      /**
       * Change the current result code of this broadcast; only works with
       * broadcasts sent through
       * {@link Context#sendOrderedBroadcast(Intent, String)
       * Context.sendOrderedBroadcast}.  Often uses the
       * Activity {@link android.app.Activity#RESULT_CANCELED} and
       * {@link android.app.Activity#RESULT_OK} constants, though the
       * actual meaning of this value is ultimately up to the broadcaster.
       *
       * <p class="note">This method does not work with non-ordered broadcasts such
       * as those sent with {@link Context#sendBroadcast(Intent)
       * Context.sendBroadcast}</p>
       *
       * @param code The new result code.
       *
       * @see #setResult(int, String, Bundle)
       */
      public final void setResultCode(int code) {
          checkSynchronousHint();
          mPendingResult.mResultCode = code;
      }
  
      /**
       * Retrieve the current result code, as set by the previous receiver.
       *
       * @return int The current result code.
       */
      public final int getResultCode() {
          return mPendingResult != null ? mPendingResult.mResultCode : 0;
      }
  
      /**
       * Change the current result data of this broadcast; only works with
       * broadcasts sent through
       * {@link Context#sendOrderedBroadcast(Intent, String)
       * Context.sendOrderedBroadcast}.  This is an arbitrary
       * string whose interpretation is up to the broadcaster.
       *
       * <p><strong>This method does not work with non-ordered broadcasts such
       * as those sent with {@link Context#sendBroadcast(Intent)
       * Context.sendBroadcast}</strong></p>
       *
       * @param data The new result data; may be null.
       *
       * @see #setResult(int, String, Bundle)
       */
      public final void setResultData(String data) {
          checkSynchronousHint();
          mPendingResult.mResultData = data;
      }
  
      /**
       * Retrieve the current result data, as set by the previous receiver.
       * Often this is null.
       *
       * @return String The current result data; may be null.
       */
      public final String getResultData() {
          return mPendingResult != null ? mPendingResult.mResultData : null;
      }
  
      /**
       * Change the current result extras of this broadcast; only works with
       * broadcasts sent through
       * {@link Context#sendOrderedBroadcast(Intent, String)
       * Context.sendOrderedBroadcast}.  This is a Bundle
       * holding arbitrary data, whose interpretation is up to the
       * broadcaster.  Can be set to null.  Calling this method completely
       * replaces the current map (if any).
       *
       * <p><strong>This method does not work with non-ordered broadcasts such
       * as those sent with {@link Context#sendBroadcast(Intent)
       * Context.sendBroadcast}</strong></p>
       *
       * @param extras The new extra data map; may be null.
       *
       * @see #setResult(int, String, Bundle)
       */
      public final void setResultExtras(Bundle extras) {
          checkSynchronousHint();
          mPendingResult.mResultExtras = extras;
      }
  
      /**
       * Retrieve the current result extra data, as set by the previous receiver.
       * Any changes you make to the returned Map will be propagated to the next
       * receiver.
       *
       * @param makeMap If true then a new empty Map will be made for you if the
       *                current Map is null; if false you should be prepared to
       *                receive a null Map.
       *
       * @return Map The current extras map.
       */
      public final Bundle getResultExtras(boolean makeMap) {
          if (mPendingResult == null) {
              return null;
          }
          Bundle e = mPendingResult.mResultExtras;
          if (!makeMap) return e;
          if (e == null) mPendingResult.mResultExtras = e = new Bundle();
          return e;
      }
  
      /**
       * Change all of the result data returned from this broadcasts; only works
       * with broadcasts sent through
       * {@link Context#sendOrderedBroadcast(Intent, String)
       * Context.sendOrderedBroadcast}.  All current result data is replaced
       * by the value given to this method.
       *
       * <p><strong>This method does not work with non-ordered broadcasts such
       * as those sent with {@link Context#sendBroadcast(Intent)
       * Context.sendBroadcast}</strong></p>
       *
       * @param code The new result code.  Often uses the
       * Activity {@link android.app.Activity#RESULT_CANCELED} and
       * {@link android.app.Activity#RESULT_OK} constants, though the
       * actual meaning of this value is ultimately up to the broadcaster.
       * @param data The new result data.  This is an arbitrary
       * string whose interpretation is up to the broadcaster; may be null.
       * @param extras The new extra data map.  This is a Bundle
       * holding arbitrary data, whose interpretation is up to the
       * broadcaster.  Can be set to null.  This completely
       * replaces the current map (if any).
       */
      public final void setResult(int code, String data, Bundle extras) {
          checkSynchronousHint();
          mPendingResult.mResultCode = code;
          mPendingResult.mResultData = data;
          mPendingResult.mResultExtras = extras;
      }
  
      /**
       * Returns the flag indicating whether or not this receiver should
       * abort the current broadcast.
       *
       * @return True if the broadcast should be aborted.
       */
      public final boolean getAbortBroadcast() {
          return mPendingResult != null ? mPendingResult.mAbortBroadcast : false;
      }
  
      /**
       * Sets the flag indicating that this receiver should abort the
       * current broadcast; only works with broadcasts sent through
       * {@link Context#sendOrderedBroadcast(Intent, String)
       * Context.sendOrderedBroadcast}.  This will prevent
       * any other broadcast receivers from receiving the broadcast. It will still
       * call {@link #onReceive} of the BroadcastReceiver that the caller of
       * {@link Context#sendOrderedBroadcast(Intent, String)
       * Context.sendOrderedBroadcast} passed in.
       *
       * <p><strong>This method does not work with non-ordered broadcasts such
       * as those sent with {@link Context#sendBroadcast(Intent)
       * Context.sendBroadcast}</strong></p>
       */
      public final void abortBroadcast() {
          checkSynchronousHint();
          mPendingResult.mAbortBroadcast = true;
      }
  
      /**
       * Clears the flag indicating that this receiver should abort the current
       * broadcast.
       */
      public final void clearAbortBroadcast() {
          if (mPendingResult != null) {
              mPendingResult.mAbortBroadcast = false;
          }
      }
  
      /**
       * Returns true if the receiver is currently processing an ordered
       * broadcast.
       */
      public final boolean isOrderedBroadcast() {
          return mPendingResult != null ? mPendingResult.mOrderedHint : false;
      }
  
      /**
       * Returns true if the receiver is currently processing the initial
       * value of a sticky broadcast -- that is, the value that was last
       * broadcast and is currently held in the sticky cache, so this is
       * not directly the result of a broadcast right now.
       */
      public final boolean isInitialStickyBroadcast() {
          return mPendingResult != null ? mPendingResult.mInitialStickyHint : false;
      }
  
      /**
       * For internal use, sets the hint about whether this BroadcastReceiver is
       * running in ordered mode.
       */
      public final void setOrderedHint(boolean isOrdered) {
          // Accidentally left in the SDK.
      }
  
      /**
       * For internal use to set the result data that is active. @hide
       */
      @UnsupportedAppUsage
      public final void setPendingResult(PendingResult result) {
          mPendingResult = result;
      }
  
      /**
       * For internal use to set the result data that is active. @hide
       */
      @UnsupportedAppUsage
      public final PendingResult getPendingResult() {
          return mPendingResult;
      }
  
      /** @hide */
      public int getSendingUserId() {
          return mPendingResult.mSendingUser;
      }
  
      /**
       * Control inclusion of debugging help for mismatched
       * calls to {@link Context#registerReceiver(BroadcastReceiver, IntentFilter)
       * Context.registerReceiver()}.
       * If called with true, before given to registerReceiver(), then the
       * callstack of the following {@link Context#unregisterReceiver(BroadcastReceiver)
       * Context.unregisterReceiver()} call is retained, to be printed if a later
       * incorrect unregister call is made.  Note that doing this requires retaining
       * information about the BroadcastReceiver for the lifetime of the app,
       * resulting in a leak -- this should only be used for debugging.
       */
      public final void setDebugUnregister(boolean debug) {
          mDebugUnregister = debug;
      }
  
      /**
       * Return the last value given to {@link #setDebugUnregister}.
       */
      public final boolean getDebugUnregister() {
          return mDebugUnregister;
      }
  
      void checkSynchronousHint() {
          if (mPendingResult == null) {
              throw new IllegalStateException("Call while result is not pending");
          }
  
          // Note that we don't assert when receiving the initial sticky value,
          // since that may have come from an ordered broadcast.  We'll catch
          // them later when the real broadcast happens again.
          if (mPendingResult.mOrderedHint || mPendingResult.mInitialStickyHint) {
              return;
          }
          RuntimeException e = new RuntimeException(
                  "BroadcastReceiver trying to return result during a non-ordered broadcast");
          e.fillInStackTrace();
          Log.e("BroadcastReceiver", e.getMessage(), e);
      }
  }
  
  