/*
* 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 androidx.media3.datasource;
import androidx.media3.common.C;
import androidx.media3.common.util.Assertions;
import androidx.media3.common.util.UnstableApi;
import java.io.IOException;
import java.io.InputStream;
/**
* Allows data corresponding to a given {@link DataSpec} to be read from a {@link DataSource} and
* consumed through an {@link InputStream}.
*/
@UnstableApi
public final class DataSourceInputStream extends InputStream {
private final DataSource dataSource;
private final DataSpec dataSpec;
private final byte[] singleByteArray;
private boolean opened = false;
private boolean closed = false;
private long totalBytesRead;
/**
* @param dataSource The {@link DataSource} from which the data should be read.
* @param dataSpec The {@link DataSpec} defining the data to be read from {@code dataSource}.
*/
public DataSourceInputStream(DataSource dataSource, DataSpec dataSpec) {
this.dataSource = dataSource;
this.dataSpec = dataSpec;
singleByteArray = new byte[1];
}
/** Returns the total number of bytes that have been read or skipped. */
public long bytesRead() {
return totalBytesRead;
}
/**
* Optional call to open the underlying {@link DataSource}.
*
* <p>Calling this method does nothing if the {@link DataSource} is already open. Calling this
* method is optional, since the read and skip methods will automatically open the underlying
* {@link DataSource} if it's not open already.
*
* @throws IOException If an error occurs opening the {@link DataSource}.
*/
public void open() throws IOException {
checkOpened();
}
@Override
public int read() throws IOException {
int length = read(singleByteArray);
return length == -1 ? -1 : (singleByteArray[0] & 0xFF);
}
@Override
public int read(byte[] buffer) throws IOException {
return read(buffer, 0, buffer.length);
}
@Override
public int read(byte[] buffer, int offset, int length) throws IOException {
Assertions.checkState(!closed);
checkOpened();
int bytesRead = dataSource.read(buffer, offset, length);
if (bytesRead == C.RESULT_END_OF_INPUT) {
return -1;
} else {
totalBytesRead += bytesRead;
return bytesRead;
}
}
@Override
public void close() throws IOException {
if (!closed) {
dataSource.close();
closed = true;
}
}
private void checkOpened() throws IOException {
if (!opened) {
dataSource.open(dataSpec);
opened = true;
}
}
}