Merge changes from topic "dynamic_system.data_transfer.shared_memory.size"

* changes:
  dynsystem.SparseInputStream: Implement read(buf, off, len)
  dynsystem: Enlarge default shared memory size and allow size override

packages/DynamicSystemInstallationService/src/com/android/dynsystem/InstallationAsyncTask.java

@@ -23,9 +23,11 @@ import android.os.AsyncTask;
 import android.os.Build;
 import android.os.MemoryFile;
 import android.os.ParcelFileDescriptor;
+import android.os.SystemProperties;
 import android.os.image.DynamicSystemManager;
 import android.service.persistentdata.PersistentDataBlockManager;
 import android.util.Log;
+import android.util.Range;
 import android.webkit.URLUtil;
 
 import org.json.JSONException;
@@ -48,7 +50,12 @@ class InstallationAsyncTask extends AsyncTask<String, Long, Throwable> {
 
     private static final String TAG = "InstallationAsyncTask";
 
-    private static final int READ_BUFFER_SIZE = 1 << 13;
+    private static final int MIN_SHARED_MEMORY_SIZE = 8 << 10; // 8KiB
+    private static final int MAX_SHARED_MEMORY_SIZE = 1024 << 10; // 1MiB
+    private static final int DEFAULT_SHARED_MEMORY_SIZE = 64 << 10; // 64KiB
+    private static final String SHARED_MEMORY_SIZE_PROP =
+            "dynamic_system.data_transfer.shared_memory.size";
+
     private static final long MIN_PROGRESS_TO_PUBLISH = 1 << 27;
 
     private static final List<String> UNSUPPORTED_PARTITIONS =
@@ -131,6 +138,7 @@ class InstallationAsyncTask extends AsyncTask<String, Long, Throwable> {
         void onResult(int resultCode, Throwable detail);
     }
 
+    private final int mSharedMemorySize;
     private final String mUrl;
     private final String mDsuSlot;
     private final String mPublicKey;
@@ -164,6 +172,11 @@ class InstallationAsyncTask extends AsyncTask<String, Long, Throwable> {
             Context context,
             DynamicSystemManager dynSystem,
             ProgressListener listener) {
+        mSharedMemorySize =
+                Range.create(MIN_SHARED_MEMORY_SIZE, MAX_SHARED_MEMORY_SIZE)
+                        .clamp(
+                                SystemProperties.getInt(
+                                        SHARED_MEMORY_SIZE_PROP, DEFAULT_SHARED_MEMORY_SIZE));
         mUrl = url;
         mDsuSlot = dsuSlot;
         mPublicKey = publicKey;
@@ -541,10 +554,10 @@ class InstallationAsyncTask extends AsyncTask<String, Long, Throwable> {
 
         Log.d(TAG, "Start installing: " + partitionName);
 
-        MemoryFile memoryFile = new MemoryFile("dsu_" + partitionName, READ_BUFFER_SIZE);
+        MemoryFile memoryFile = new MemoryFile("dsu_" + partitionName, mSharedMemorySize);
         ParcelFileDescriptor pfd = new ParcelFileDescriptor(memoryFile.getFileDescriptor());
 
-        mInstallationSession.setAshmem(pfd, READ_BUFFER_SIZE);
+        mInstallationSession.setAshmem(pfd, memoryFile.length());
 
         mPartitionName = partitionName;
         mPartitionSize = partitionSize;
@@ -553,10 +566,10 @@ class InstallationAsyncTask extends AsyncTask<String, Long, Throwable> {
 
         long prevInstalledSize = 0;
         long installedSize = 0;
-        byte[] bytes = new byte[READ_BUFFER_SIZE];
+        byte[] bytes = new byte[memoryFile.length()];
         int numBytesRead;
 
-        while ((numBytesRead = sis.read(bytes, 0, READ_BUFFER_SIZE)) != -1) {
+        while ((numBytesRead = sis.read(bytes, 0, bytes.length)) != -1) {
             if (isCancelled()) {
                 return;
             }

packages/DynamicSystemInstallationService/src/com/android/dynsystem/SparseInputStream.java

@@ -133,36 +133,32 @@ public class SparseInputStream extends InputStream {
         return mLeft == 0;
     }
 
-    /**
+    @Override
-     * It overrides the InputStream.read(byte[] buf)
+    public int read(byte[] buf, int off, int len) throws IOException {
-     */
-    public int read(byte[] buf) throws IOException {
         if (!mIsSparse) {
-            return mIn.read(buf);
+            return mIn.read(buf, off, len);
         }
         if (prepareChunk()) return -1;
         int n = -1;
         switch (mCur.mChunkType) {
             case SparseChunk.RAW:
-                n = mIn.read(buf, 0, (int) min(mLeft, buf.length));
+                n = mIn.read(buf, off, (int) min(mLeft, len));
                 mLeft -= n;
                 return n;
             case SparseChunk.DONTCARE:
-                n = (int) min(mLeft, buf.length);
+                n = (int) min(mLeft, len);
-                Arrays.fill(buf, 0, n - 1, (byte) 0);
+                Arrays.fill(buf, off, off + n, (byte) 0);
                 mLeft -= n;
                 return n;
             case SparseChunk.FILL:
                 // The FILL type is rarely used, so use a simple implmentation.
-                return super.read(buf);
+                return super.read(buf, off, len);
             default:
                 throw new IOException("Unsupported Chunk:" + mCur.toString());
         }
     }
 
-    /**
+    @Override
-     * It overrides the InputStream.read()
-     */
     public int read() throws IOException {
         if (!mIsSparse) {
             return mIn.read();