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diff --git a/libjava/classpath/gnu/javax/sound/sampled/gstreamer/lines/GstPipeline.java b/libjava/classpath/gnu/javax/sound/sampled/gstreamer/lines/GstPipeline.java
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+/* GstPipeline.java -- Represents a Gstreamer Pipeline.
+ Copyright (C) 2007 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath 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; either version 2, or (at your option)
+any later version.
+
+GNU Classpath 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 GNU Classpath; 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 gnu.javax.sound.sampled.gstreamer.lines;
+
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.prefs.Preferences;
+
+import javax.sound.sampled.LineUnavailableException;
+
+import gnu.classpath.Pointer;
+
+/**
+ * This class represent a GStreamer pipeline and is resposible to handle the
+ * flow of data to and from the GStreamer native backend.
+ *
+ * @author Mario Torre <neugens@limasoftware.net>
+ */
+public class GstPipeline
+{
+  /*
+   * Implementation note:
+   * This class is at first a bit confusing as it serves as a gateway
+   * to a real filesystem named pipe.
+   * The pipelines is shared by the gstreamer backend and by the java code.
+   * If the operation we are performing is to play a given stream of bytes,
+   * we need to open the java side of the pipeline for writing, which is done
+   * in the prepareWrite method. At the same time, the native side of the code
+   * need to open the pipeline in read mode, to get access to the data,
+   * and hence, act as a source element. This is why you will see terms
+   * like "read" or "source" in methods that are used to write in the pipeline,
+   * in other words, each the native operation is the opposite of the java
+   * side operation.
+   * Opening the pipe to record audio data from the sound card works the same
+   * except that all the operation are inverted.
+   */
+
+  // These enums are used in the native code also, changes here must reflect
+  // changes in the native code.
+  public static enum State
+  {
+    PLAY, PAUSE, STOP, CLOSE
+  }
+
+  private static final int READ = 0;
+  private static final int WRITE = 1;
+  private static final int QUEUED = 1;
+
+  private static final String CAPACITY_KEY = "Capacity";
+
+  private static final Object [] lock = new Object[0];
+
+  /*
+   * Preference subsystem. We use this to store some system specific settings.
+   */
+  protected Preferences prefs =
+    Preferences.userNodeForPackage(GstPipeline.class).node("GStreamer");
+
+  // used by the native code, stores the size of the named pipeline
+  // created by the operating system.
+  private long capacity = -1;
+
+  /** Represents the playing state of this Line. */
+  private State state = State.STOP;
+
+  /** The name of the named pipe. */
+  // Will be setup and filled in the native code. See the native library
+  // for details.
+  private String name = null;
+
+  /** This is the named pipe that will be read by the gstreamer backend. */
+  private FileOutputStream output = null;
+
+  /**
+   * Defines if we are getting data from a sink pipe
+   * or writing to a source pipe.
+   */
+  private boolean source = true;
+
+  /** Indicate that we are ready to process audio data to/from the pipe. */
+  private boolean ready = false;
+
+  /**
+   * This is the native GStreamer Pipeline.
+   */
+  // This field is used by the native code, so any change to it must be
+  // followed by similar changes in the native peer.
+  private Pointer pipeline = null;
+
+  /**
+   * Creates a new GstPipeline with a capacity of
+   * {@link GstDataLine#DEFAULT_BUFFER_SIZE}.
+   *
+   * @see GstDataLine#DEFAULT_BUFFER_SIZE
+   */
+  public GstPipeline()
+  {
+    this(GstDataLine.DEFAULT_BUFFER_SIZE);
+  }
+
+  /**
+   * Creates a new GstPipeline with a capacity of bufferSize.
+   * @see GstDataLine#DEFAULT_BUFFER_SIZE
+   */
+  public GstPipeline(int bufferSize)
+  {
+    // see if we need to detect the size of the named pipe or we can use
+    // an already computet default for this system.
+    // Note that this is very different from the bufferSize parameter,
+    // see below.
+    capacity = prefs.getLong(CAPACITY_KEY, -1);
+    if (capacity == -1)
+      {
+        synchronized (lock)
+          {
+            capacity = detect_pipe_size();
+          }
+
+        prefs.putLong(CAPACITY_KEY, capacity);
+      }
+
+    // FIXME: bufferSize actually not used nor needed by the backend.
+    // Applications that expects a buffer of different size will be a
+    // bit disappointed by that..
+    init_instance();
+
+    // need to remove the named pipe in case of abnormal termination
+    Runtime.getRuntime().addShutdownHook(new CleanPipeline());
+  }
+
+  /**
+   * Creates a source pipeline. A source pipeline is a pipe you send data for
+   * processing using the write method.
+   */
+  public void createForWrite() throws LineUnavailableException
+  {
+    // create the named pipe
+    if (!create_named_pipe(this.pipeline))
+      throw new LineUnavailableException("Unable to create filesystem pipe");
+
+    open_native_pipe(this.pipeline, READ);
+    prepareWrite();
+
+    this.source = true;
+  }
+
+  /**
+   * @return the state
+   */
+  public State getState()
+  {
+    return this.state;
+  }
+
+  /**
+   * Closes this pipeline.
+   * Short hand for #setState(State.STOP).
+   */
+  public void close()
+  {
+    setState(State.STOP);
+  }
+
+  /**
+   * @param state the state to set
+   */
+  public void setState(final State state)
+  {
+    int _state = -1;
+    switch (state)
+      {
+        case PLAY:
+          _state = 0;
+          break;
+
+        case PAUSE:
+          _state = 1;
+          break;
+
+        case STOP: case CLOSE:
+          _state = 2;
+          closePipe();
+          break;
+      }
+
+    if (set_state(pipeline, _state))
+      GstPipeline.this.state = state;
+  }
+
+  /**
+   * Return a reference to the GstPipeline native class as a Pointer object.
+   * This method is intended as an helper accessor and the returned pointer
+   * needs to be casted and used in the native code only.
+   *
+   * @return Pointer to the native GstPipeline class.
+   */
+  public Pointer getNativeClass()
+  {
+    return this.pipeline;
+  }
+
+  /**
+   * Write length bytes from the given buffer into this pipeline,
+   * starting at offset.
+   * This method block if the pipeline can't accept more data.
+   *
+   * @param buffer
+   * @param offset
+   * @param length
+   * @return
+   */
+  public int write(byte[] buffer, int offset, int length)
+  {
+    if (this.state == State.STOP)
+      return -1;
+    else if (this.state == State.PAUSE)
+      return 0;
+    else if (!ready)
+      return -1;
+
+    try
+      {
+        if (output != null)
+          {
+            output.write(buffer, offset, length);
+            return length;
+          }
+        return 0;
+      }
+    catch (Exception e)
+      {
+        /* nothing to do */
+      }
+
+    return -1;
+  }
+
+  public int read(byte[] buffer, int offset, int length)
+  {
+    return 0;
+  }
+
+  public int available()
+  {
+    if (this.source)
+      return available(this.pipeline, READ);
+    else
+      return available(this.pipeline, WRITE);
+  }
+
+  /**
+   * Wait for remaining data to be enqueued in the pipeline.
+   */
+  public void drain()
+  {
+    if (this.state == State.STOP)
+      return;
+
+    try
+      {
+        // wait untill there is anymore data in the pipe
+        while (available(this.pipeline, QUEUED) > 0)
+          Thread.sleep(3000);
+
+        // plus a bit to allow data to be processed
+        Thread.sleep(1000);
+      }
+    catch (InterruptedException e)
+      {
+        /* nothing to do*/
+      }
+  }
+
+  /**
+   * Flush all the data currently waiting to be processed.
+   */
+  public void flush()
+  {
+    try
+      {
+        if (source)
+          this.output.flush();
+      }
+    catch (IOException e)
+      {
+        /* nothing */
+      }
+  }
+
+  private void closePipe()
+  {
+    try
+      {
+        GstPipeline.this.flush();
+        if (source)
+          GstPipeline.this.output.close();
+      }
+    catch (IOException e)
+      {
+        /* nothing to do */
+      }
+  }
+
+  private void prepareWrite()
+  {
+    try
+      {
+        // if this is not completed for some reason, we will catch
+        // in the write method. As this call can block, we assume we will
+        // succeed and that the dataline can get data.
+        GstPipeline.this.ready = true;
+        GstPipeline.this.output = new FileOutputStream(name);
+      }
+    catch (Exception e)
+      {
+        GstPipeline.this.ready = false;
+      }
+  }
+
+  /* ***** native ***** */
+
+  /**
+   * Initialize the native peer and enables the object cache.
+   * It is meant to be used by the static initializer.
+   */
+  native private static final void init_id_cache();
+
+  /**
+   * Set the playing state of this pipeline.
+   */
+  native private static final boolean set_state(Pointer pipeline, int state);
+
+  /**
+   * Get the number of bytes currently available for reading or writing
+   * from the pipeline.
+   */
+  native private static final int available(Pointer pipeline, int mode);
+
+  /**
+   * Open the native pipeline with the given mode.
+   */
+  native private static final void open_native_pipe(Pointer jpipeline,
+                                                    int mode);
+
+  /**
+   * Close the native pipeline.
+   */
+  native private static final void close_native_pipe(Pointer jpipeline);
+
+  /**
+   * Initialize the native peer and enables the object cache.
+   * It is meant to be used by the class constructor.
+   */
+  native private final void init_instance();
+
+  /**
+   * Crates the named pipe used to pass data between the application code
+   * and gstreamer.
+   */
+  native private final boolean create_named_pipe(Pointer jpipeline);
+
+  /**
+   * Detect and return the size of the filesystem named pipe.
+   */
+  native private final long detect_pipe_size();
+
+  private class CleanPipeline extends Thread
+  {
+    public void run()
+    {
+      GstPipeline.close_native_pipe(GstPipeline.this.pipeline);
+    }
+  }
+
+  static
+  {
+    System.loadLibrary("gstreamerpeer"); //$NON-NLS-1$
+    init_id_cache();
+  }
+}