view pulseaudio/src/java/org/classpath/icedtea/pulseaudio/PulseAudioSourceDataLine.java @ 2626:9ef423f94e8c

PR1741: Synchronize access to shared variable The variable writeInterrupted is accessed everywhere while holding a lock on 'this' object, except in one location. Fix that. 2012-06-28 Omair Majid <omajid@redhat.com> * pulseaudio/src/java/org/classpath/icedtea/pulseaudio/PulseAudioSourceDataLine.java (write): Synchronize access to writeInterrupted flag.
author Omair Majid <omajid@redhat.com>
date Thu, 28 Jun 2012 20:04:54 -0400
parents b746d080787e
children
line wrap: on
line source

/* PulseAudioSourceDataLine.java
   Copyright (C) 2008 Red Hat, Inc.

This file is part of IcedTea.

IcedTea is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as published by
the Free Software Foundation, version 2.

IcedTea is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with IcedTea; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module.  An independent module is a module which is not derived from
or based on this library.  If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so.  If you do not wish to do so, delete this
exception statement from your version.
 */

package org.classpath.icedtea.pulseaudio;

import java.util.ArrayList;

import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.Line;
import javax.sound.sampled.LineListener;
import javax.sound.sampled.LineUnavailableException;
import javax.sound.sampled.SourceDataLine;

import org.classpath.icedtea.pulseaudio.Debug.DebugLevel;

public final class PulseAudioSourceDataLine extends PulseAudioDataLine
        implements SourceDataLine, PulseAudioPlaybackLine {

    private PulseAudioVolumeControl volumeControl;

    public static final String DEFAULT_SOURCEDATALINE_NAME = "Audio Stream";

    /*
     * Package-private constructor only called by PulseAudioMixer
     */
    PulseAudioSourceDataLine(AudioFormat[] formats, AudioFormat defaultFormat) {

        this.supportedFormats = formats;
        this.lineListeners = new ArrayList<LineListener>();
        this.defaultFormat = defaultFormat;
        this.currentFormat = defaultFormat;
        this.streamName = DEFAULT_SOURCEDATALINE_NAME;

    }

    @Override
    synchronized public void open(AudioFormat format, int bufferSize)
            throws LineUnavailableException {

        super.open(format, bufferSize);

        volumeControl = new PulseAudioVolumeControl(this, eventLoop);
        controls.add(volumeControl);

        PulseAudioMixer parentMixer = PulseAudioMixer.getInstance();
        parentMixer.addSourceLine(this);

        Debug.println(DebugLevel.Verbose, "PulseAudioSourceDataLine.open(): "
                + "line opened");

    }

    @Override
    public void open(AudioFormat format) throws LineUnavailableException {
        open(format, DEFAULT_BUFFER_SIZE);
    }

    // FIXME
    public byte[] native_set_volume(float value) {
        synchronized (eventLoop.threadLock) {
            return stream.native_set_volume(value);
        }
    }

    public byte[] native_update_volume() {
        synchronized (eventLoop.threadLock) {
            return stream.native_update_volume();
        }
    }
    
    @Override
    public float getCachedVolume() {
        return stream.getCachedVolume();
    }

    @Override
    synchronized public void setCachedVolume(float value) {
        stream.setCachedVolume(value);
    }

    @Override
    protected void connectLine(int bufferSize, Stream masterStream)
            throws LineUnavailableException {
        StreamBufferAttributes bufferAttributes =
            new StreamBufferAttributes(
                    bufferSize,
                    bufferSize / 4,
                    bufferSize / 8,
                    Math.max(bufferSize / 10, 100),
                    0);

        if (masterStream != null) {
            synchronized (eventLoop.threadLock) {
                stream.connectForPlayback(Stream.DEFAULT_DEVICE,
                        bufferAttributes, masterStream.getStreamPointer());
            }
        } else {
            synchronized (eventLoop.threadLock) {
                stream.connectForPlayback(Stream.DEFAULT_DEVICE,
                        bufferAttributes, null);
            }
        }
    }

    @Override
    public int write(byte[] data, int offset, int length) {
        // can't call write() without open()ing first, but can call write()
        // without start()ing
        synchronized (this) {
            writeInterrupted = false;
        }

        if (!isOpen()) {
            // A closed line can write exactly 0 bytes.
            return 0;
        }

        int frameSize = currentFormat.getFrameSize();
        if (length % frameSize != 0) {
            throw new IllegalArgumentException(
                    "amount of data to write does not represent an integral number of frames");
        }
        
        if (length < 0) {
            throw new IllegalArgumentException("length is negative");
        }
        
        if (length < 0 || offset < 0 || offset > data.length - length) {
            throw new ArrayIndexOutOfBoundsException(
                    "Overflow condition: buffer.length=" + data.length + 
                            " offset= " + offset + " length=" + length );
        }

        int position = offset;
        int remainingLength = length;
        int availableSize = 0;

        int sizeWritten = 0;

        boolean interrupted = false;

        while (remainingLength != 0) {

            synchronized (eventLoop.threadLock) {

                do {
                    synchronized (this) {
                        if (writeInterrupted) {
                            return sizeWritten;
                        }
                    }

                    if (availableSize == -1) {
                        return sizeWritten;
                    }
                    availableSize = stream.getWritableSize();

                    if (availableSize == 0) {
                        try {
                            eventLoop.threadLock.wait(100);
                        } catch (InterruptedException e) {
                            // ignore for now
                            interrupted = true;
                        }

                    }

                } while (availableSize == 0);

                if (availableSize > remainingLength) {
                    availableSize = remainingLength;
                }

                // only write entire frames, so round down avialableSize to
                // a multiple of frameSize
                availableSize = (availableSize / frameSize) * frameSize;

                synchronized (this) {
                    if (writeInterrupted) {
                        return sizeWritten;
                    }
                    /* write a little bit of the buffer */
                    stream.write(data, position, availableSize);
                }

                sizeWritten += availableSize;
                position += availableSize;
                remainingLength -= availableSize;

                framesSinceOpen += availableSize / frameSize;

            }
        }

        // all the data should have been played by now
        assert (sizeWritten == length);

        if (interrupted) {
            Thread.currentThread().interrupt();
        }

        return sizeWritten;
    }

    @Override
    public int available() {
        synchronized (eventLoop.threadLock) {
            return stream.getWritableSize();
        }
    };

    @Override
    public int getFramePosition() {
        return (int) framesSinceOpen;
    }

    @Override
    public long getLongFramePosition() {
        return framesSinceOpen;
    }

    @Override
    public long getMicrosecondPosition() {

        float frameRate = currentFormat.getFrameRate();
        float time = framesSinceOpen / frameRate; // seconds
        long microseconds = (long) (time * SECONDS_TO_MICROSECONDS);
        return microseconds;
    }

    @Override
    public void drain() {

        synchronized (this) {
            writeInterrupted = true;
        }

        do {
            synchronized (this) {
                if (!isOpen()) {
                    return;
                }
                if (getBytesInBuffer() == 0) {
                    return;
                }
                if (isStarted) {
                    break;
                }
                try {
                    this.wait(100);
                } catch (InterruptedException e) {
                    return;
                }
            }
        } while (!isStarted);

        Operation operation;

        synchronized (eventLoop.threadLock) {
            operation = stream.drain();
        }

        operation.waitForCompletion();
        operation.releaseReference();

    }

    @Override
    public void flush() {
        synchronized (this) {
            writeInterrupted = true;
        }

        if (isOpen()) {
            Operation operation;
            synchronized (eventLoop.threadLock) {
                operation = stream.flush();
            }

            operation.waitForCompletion();
            operation.releaseReference();
        }

    }

    @Override
    synchronized public void close() {

        if (!isOpen()) {
            return;
        }

        writeInterrupted = true;

        PulseAudioMixer parent = PulseAudioMixer.getInstance();
        parent.removeSourceLine(this);

        super.close();

        Debug.println(DebugLevel.Verbose, "PulseAudioSourceDataLine.close():"
                + " line closed");

    }

    @Override
    public Line.Info getLineInfo() {
        return new DataLine.Info(SourceDataLine.class, supportedFormats,
                StreamBufferAttributes.MIN_VALUE,
                StreamBufferAttributes.MAX_VALUE);
    }

}