Extract crop hint rect from source wallpaper image

Setting the wallpaper is still synchronous: the caller blocks until any
backend cropping/manipulation has completed.  There is a timeout (currently
30 seconds) on that to avoid wedging the caller arbitrarily.

Bug 25454501

Change-Id: Idca2fe1b10e4fa34d6d54865903d9a1b9e305e3c

core/java/android/app/IWallpaperManager.aidl

@@ -35,10 +35,16 @@ interface IWallpaperManager {
      * 'which' is some combination of:
      *   FLAG_SET_SYSTEM
      *   FLAG_SET_LOCK
+     *
+     * A 'null' cropHint rectangle is explicitly permitted as a sentinel for "whatever
+     * the source image's bounding rect is."
+     *
+     * The completion callback's "onWallpaperChanged()" method is invoked when the
+     * new wallpaper content is ready to display.
      */
     ParcelFileDescriptor setWallpaper(String name, in String callingPackage,
-            out Bundle extras, int which);
-    
+            in Rect cropHint, out Bundle extras, int which, IWallpaperManagerCallback completion);
+
     /**
      * Set the live wallpaper. This only affects the system wallpaper.
      */
@@ -54,14 +60,14 @@ interface IWallpaperManager {
      */
     ParcelFileDescriptor getWallpaper(IWallpaperManagerCallback cb,
             out Bundle outParams);
-    
+
     /**
      * If the current system wallpaper is a live wallpaper component, return the
      * information about that wallpaper.  Otherwise, if it is a static image,
      * simply return null.
      */
     WallpaperInfo getWallpaperInfo();
-    
+
     /**
      * Clear the system wallpaper.
      */

core/java/android/app/WallpaperManager.java

@@ -64,6 +64,8 @@ import java.io.InputStream;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.util.List;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
 
 /**
  * Provides access to the system wallpaper. With WallpaperManager, you can
@@ -770,18 +772,26 @@ public class WallpaperManager {
             return 0;
         }
         final Bundle result = new Bundle();
+        final WallpaperSetCompletion completion = new WallpaperSetCompletion();
         try {
             Resources resources = mContext.getResources();
             /* Set the wallpaper to the default values */
             ParcelFileDescriptor fd = sGlobals.mService.setWallpaper(
                     "res:" + resources.getResourceName(resid),
-                    mContext.getOpPackageName(), result, which);
+                    mContext.getOpPackageName(), null, result, which, completion);
             if (fd != null) {
                 FileOutputStream fos = null;
+                boolean ok = false;
                 try {
                     fos = new ParcelFileDescriptor.AutoCloseOutputStream(fd);
                     copyStreamToWallpaperFile(resources.openRawResource(resid), fos);
+                    // The 'close()' is the trigger for any server-side image manipulation,
+                    // so we must do that before waiting for completion.
+                    fos.close();
+                    completion.waitForCompletion();
                 } finally {
+                    // Might be redundant but completion shouldn't wait unless the write
+                    // succeeded; this is a fallback if it threw past the close+wait.
                     IoUtils.closeQuietly(fos);
                 }
             }
@@ -876,14 +886,17 @@ public class WallpaperManager {
             return 0;
         }
         final Bundle result = new Bundle();
+        final WallpaperSetCompletion completion = new WallpaperSetCompletion();
         try {
             ParcelFileDescriptor fd = sGlobals.mService.setWallpaper(null,
-                    mContext.getOpPackageName(), result, which);
+                    mContext.getOpPackageName(), visibleCropHint, result, which, completion);
             if (fd != null) {
                 FileOutputStream fos = null;
                 try {
                     fos = new ParcelFileDescriptor.AutoCloseOutputStream(fd);
                     fullImage.compress(Bitmap.CompressFormat.PNG, 90, fos);
+                    fos.close();
+                    completion.waitForCompletion();
                 } finally {
                     IoUtils.closeQuietly(fos);
                 }
@@ -990,14 +1003,17 @@ public class WallpaperManager {
             return 0;
         }
         final Bundle result = new Bundle();
+        final WallpaperSetCompletion completion = new WallpaperSetCompletion();
         try {
             ParcelFileDescriptor fd = sGlobals.mService.setWallpaper(null,
-                    mContext.getOpPackageName(), result, which);
+                    mContext.getOpPackageName(), visibleCropHint, result, which, completion);
             if (fd != null) {
                 FileOutputStream fos = null;
                 try {
                     fos = new ParcelFileDescriptor.AutoCloseOutputStream(fd);
                     copyStreamToWallpaperFile(bitmapData, fos);
+                    fos.close();
+                    completion.waitForCompletion();
                 } finally {
                     IoUtils.closeQuietly(fos);
                 }
@@ -1385,4 +1401,28 @@ public class WallpaperManager {
 
         return null;
     }
+
+    // Private completion callback for setWallpaper() synchronization
+    private class WallpaperSetCompletion extends IWallpaperManagerCallback.Stub {
+        final CountDownLatch mLatch;
+
+        public WallpaperSetCompletion() {
+            mLatch = new CountDownLatch(1);
+        }
+
+        public void waitForCompletion() {
+            try {
+                mLatch.await(30, TimeUnit.SECONDS);
+            } catch (InterruptedException e) {
+                // This might be legit: the crop may take a very long time. Don't sweat
+                // it in that case; we are okay with display lagging behind in order to
+                // keep the caller from locking up indeterminately.
+            }
+        }
+
+        @Override
+        public void onWallpaperChanged() throws RemoteException {
+            mLatch.countDown();
+        }
+    }
 }