Fix DataSchemeDataSource re-opening and range requests

Issue:#6192
PiperOrigin-RevId: 258592902

RELEASENOTES.md

@@ -25,6 +25,8 @@
 * Add `enable` and `disable` methods to `MediaSource` to improve resource
   management in playlists.
 * Fix issue where initial seek positions get ignored when playing a preroll ad.
+* Fix `DataSchemeDataSource` re-opening and range requests
+  ([#6192](https://github.com/google/ExoPlayer/issues/6192)).
 
 ### 2.10.3 ###
 

library/core/src/main/java/com/google/android/exoplayer2/upstream/DataSchemeDataSource.java

@@ -33,8 +33,8 @@ public final class DataSchemeDataSource extends BaseDataSource {
 
   @Nullable private DataSpec dataSpec;
   @Nullable private byte[] data;
-  private int dataLength;
+  private int endPosition;
-  private int bytesRead;
+  private int readPosition;
 
   public DataSchemeDataSource() {
     super(/* isNetwork= */ false);
@@ -44,6 +44,7 @@ public final class DataSchemeDataSource extends BaseDataSource {
   public long open(DataSpec dataSpec) throws IOException {
     transferInitializing(dataSpec);
     this.dataSpec = dataSpec;
+    readPosition = (int) dataSpec.position;
     Uri uri = dataSpec.uri;
     String scheme = uri.getScheme();
     if (!SCHEME_DATA.equals(scheme)) {
@@ -57,17 +58,21 @@ public final class DataSchemeDataSource extends BaseDataSource {
     if (uriParts[0].contains(";base64")) {
       try {
         data = Base64.decode(dataString, 0);
-        dataLength = data.length;
       } catch (IllegalArgumentException e) {
         throw new ParserException("Error while parsing Base64 encoded string: " + dataString, e);
       }
     } else {
       // TODO: Add support for other charsets.
       data = Util.getUtf8Bytes(URLDecoder.decode(dataString, C.ASCII_NAME));
-      dataLength = data.length;
+    }
+    endPosition =
+        dataSpec.length != C.LENGTH_UNSET ? (int) dataSpec.length + readPosition : data.length;
+    if (endPosition > data.length || readPosition > endPosition) {
+      data = null;
+      throw new DataSourceException(DataSourceException.POSITION_OUT_OF_RANGE);
     }
     transferStarted(dataSpec);
-    return dataLength;
+    return (long) endPosition - readPosition;
   }
 
   @Override
@@ -75,13 +80,13 @@ public final class DataSchemeDataSource extends BaseDataSource {
     if (readLength == 0) {
       return 0;
     }
-    int remainingBytes = dataLength - bytesRead;
+    int remainingBytes = endPosition - readPosition;
     if (remainingBytes == 0) {
       return C.RESULT_END_OF_INPUT;
     }
     readLength = Math.min(readLength, remainingBytes);
-    System.arraycopy(castNonNull(data), bytesRead, buffer, offset, readLength);
+    System.arraycopy(castNonNull(data), readPosition, buffer, offset, readLength);
-    bytesRead += readLength;
+    readPosition += readLength;
     bytesTransferred(readLength);
     return readLength;
   }
@@ -93,12 +98,11 @@ public final class DataSchemeDataSource extends BaseDataSource {
   }
 
   @Override
-  public void close() throws IOException {
+  public void close() {
     if (data != null) {
       data = null;
       transferEnded();
     }
     dataSpec = null;
   }
-
 }

library/core/src/test/java/com/google/android/exoplayer2/upstream/DataSchemeDataSourceTest.java

@@ -21,6 +21,7 @@ import static org.junit.Assert.fail;
 
 import android.net.Uri;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
+import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.util.Util;
 import java.io.IOException;
 import org.junit.Before;
@@ -31,6 +32,9 @@ import org.junit.runner.RunWith;
 @RunWith(AndroidJUnit4.class)
 public final class DataSchemeDataSourceTest {
 
+  private static final String DATA_SCHEME_URI =
+      "data:text/plain;base64,eyJwcm92aWRlciI6IndpZGV2aW5lX3Rlc3QiLCJjb250ZW50X2lkIjoiTWpBeE5WOTBaV"
+          + "0Z5Y3c9PSIsImtleV9pZHMiOlsiMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAiXX0=";
   private DataSource schemeDataDataSource;
 
   @Before
@@ -40,9 +44,7 @@ public final class DataSchemeDataSourceTest {
 
   @Test
   public void testBase64Data() throws IOException {
-    DataSpec dataSpec = buildDataSpec("data:text/plain;base64,eyJwcm92aWRlciI6IndpZGV2aW5lX3Rlc3QiL"
+    DataSpec dataSpec = buildDataSpec(DATA_SCHEME_URI);
-        + "CJjb250ZW50X2lkIjoiTWpBeE5WOTBaV0Z5Y3c9PSIsImtleV9pZHMiOlsiMDAwMDAwMDAwMDAwMDAwMDAwMDAwM"
-        + "DAwMDAwMDAwMDAiXX0=");
     DataSourceAsserts.assertDataSourceContent(
         schemeDataDataSource,
         dataSpec,
@@ -72,6 +74,52 @@ public final class DataSchemeDataSourceTest {
     assertThat(Util.fromUtf8Bytes(buffer, 0, 18)).isEqualTo("012345678901234567");
   }
 
+  @Test
+  public void testSequentialRangeRequests() throws IOException {
+    DataSpec dataSpec =
+        buildDataSpec(DATA_SCHEME_URI, /* position= */ 1, /* length= */ C.LENGTH_UNSET);
+    DataSourceAsserts.assertDataSourceContent(
+        schemeDataDataSource,
+        dataSpec,
+        Util.getUtf8Bytes(
+            "\"provider\":\"widevine_test\",\"content_id\":\"MjAxNV90ZWFycw==\",\"key_ids\":"
+                + "[\"00000000000000000000000000000000\"]}"));
+    dataSpec = buildDataSpec(DATA_SCHEME_URI, /* position= */ 10, /* length= */ C.LENGTH_UNSET);
+    DataSourceAsserts.assertDataSourceContent(
+        schemeDataDataSource,
+        dataSpec,
+        Util.getUtf8Bytes(
+            "\":\"widevine_test\",\"content_id\":\"MjAxNV90ZWFycw==\",\"key_ids\":"
+                + "[\"00000000000000000000000000000000\"]}"));
+    dataSpec = buildDataSpec(DATA_SCHEME_URI, /* position= */ 15, /* length= */ 5);
+    DataSourceAsserts.assertDataSourceContent(
+        schemeDataDataSource, dataSpec, Util.getUtf8Bytes("devin"));
+  }
+
+  @Test
+  public void testInvalidStartPositionRequest() throws IOException {
+    try {
+      // Try to open a range starting one byte beyond the resource's length.
+      schemeDataDataSource.open(
+          buildDataSpec(DATA_SCHEME_URI, /* position= */ 108, /* length= */ C.LENGTH_UNSET));
+      fail();
+    } catch (DataSourceException e) {
+      assertThat(e.reason).isEqualTo(DataSourceException.POSITION_OUT_OF_RANGE);
+    }
+  }
+
+  @Test
+  public void testRangeExceedingResourceLengthRequest() throws IOException {
+    try {
+      // Try to open a range exceeding the resource's length.
+      schemeDataDataSource.open(
+          buildDataSpec(DATA_SCHEME_URI, /* position= */ 97, /* length= */ 11));
+      fail();
+    } catch (DataSourceException e) {
+      assertThat(e.reason).isEqualTo(DataSourceException.POSITION_OUT_OF_RANGE);
+    }
+  }
+
   @Test
   public void testIncorrectScheme() {
     try {
@@ -99,7 +147,11 @@ public final class DataSchemeDataSourceTest {
   }
 
   private static DataSpec buildDataSpec(String uriString) {
-    return new DataSpec(Uri.parse(uriString));
+    return buildDataSpec(uriString, /* position= */ 0, /* length= */ C.LENGTH_UNSET);
+  }
+
+  private static DataSpec buildDataSpec(String uriString, int position, int length) {
+    return new DataSpec(Uri.parse(uriString), position, length, /* key= */ null);
   }
 
 }