Fix AudioNode.disconnect() to support selective disconnection.

Source/modules/webaudio/AudioNode.cpp

 /*
  * Copyright (C) 2010, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 259 matching lines @@
     if (context() != param->context()) {
         exceptionState.throwDOMException(
             SyntaxError,
             "cannot connect to an AudioParam belonging to a different audio context.");
         return;
     }
 
     param->connect(*output(outputIndex));
 }
 
+void AudioNode::disconnect()
+{
+    ASSERT(isMainThread());
+    AudioContext::AutoLocker locker(context());
+
+    // Disconnect all outgoing connections.
+    for (unsigned i = 0; i < numberOfOutputs(); ++i)
+        this->output(i)->disconnectAll();
+}
+
 void AudioNode::disconnect(unsigned outputIndex, ExceptionState& exceptionState)
 {
     ASSERT(isMainThread());
     AudioContext::AutoLocker locker(context());
 
+    // Sanity check on the output index.
+    if (outputIndex >= numberOfOutputs()) {
+        exceptionState.throwDOMException(
+            IndexSizeError,
+            ExceptionMessages::indexOutsideRange(
+                "output",

[Raymond Toy, 2015/02/12 19:45:53]

Would the error message be better if you said "output index" instead of just
"output"?

[hongchan, 2015/02/13 01:16:57]

I went back and forth on this one. Now the whole message has changed, I agree
that the 'output index' reads better.

+                outputIndex,
+                0u,
+                ExceptionMessages::InclusiveBound,
+                numberOfOutputs(),
+                ExceptionMessages::InclusiveBound));
+        return;
+    }
+
+    // Disconnect all outgoing connections from the given output.
+    AudioNodeOutput* output = this->output(outputIndex);
+    output->disconnectAll();
+}
+
+void AudioNode::disconnect(AudioNode* destination, ExceptionState& exceptionState)
+{
+    ASSERT(isMainThread());
+    AudioContext::AutoLocker locker(context());
+
+    unsigned numberOfDisconnections = 0;
+
+    // FIXME: Can this be optimized? ChannelSplitter and ChannelMerger can have
+    // 32 ports and that requires 1024 iterations to validate entire connections.
+    for (unsigned i = 0; i < numberOfOutputs(); ++i) {
+        AudioNodeOutput* output = this->output(i);
+        for (unsigned j = 0; j < destination->numberOfInputs(); ++j) {
+            AudioNodeInput* input = destination->input(j);
+            if (output->isConnectedToInput(*input)) {
+                output->disconnectInput(*input);
+                numberOfDisconnections++;
+            }
+        }
+    }
+
+    // If there is no connection to the destination, throw an exception.
+    if (numberOfDisconnections == 0) {
+        exceptionState.throwDOMException(
+            InvalidAccessError,
+            "the given destination is not connected.");
+        return;
+    }
+}
+
+void AudioNode::disconnect(AudioNode* destination, unsigned outputIndex, ExceptionState& exceptionState)
+{
+    ASSERT(isMainThread());
+    AudioContext::AutoLocker locker(context());
+
+    // Sanity check on output index.
+    if (outputIndex >= numberOfOutputs()) {
+        exceptionState.throwDOMException(
+            IndexSizeError,
+            ExceptionMessages::indexOutsideRange(
+                "output",

[Raymond Toy, 2015/02/12 19:45:53]

Same comment as on line 300.

+                outputIndex,
+                0u,
+                ExceptionMessages::InclusiveBound,
+                numberOfOutputs(),
+                ExceptionMessages::InclusiveBound));
+        return;
+    }
+
+    unsigned numberOfDisconnections = 0;
+    AudioNodeOutput* output = this->output(outputIndex);
+
+    // Sanity check on destination inputs and disconnect when possible.
+    for (unsigned i = 0; i < destination->numberOfInputs(); ++i) {
+        AudioNodeInput* input = destination->input(i);
+        if (output->isConnectedToInput(*input)) {
+            output->disconnectInput(*input);
+            numberOfDisconnections++;
+        }
+    }
+
+    // If there is no connection to the destination, throw an exception.
+    if (numberOfDisconnections == 0) {
+        exceptionState.throwDOMException(
+            InvalidAccessError,
+            "output (" + String::number(outputIndex) + ") is not connected to the given destination.");
+        return;
+    }
+}
+
+void AudioNode::disconnect(AudioNode* destination, unsigned outputIndex, unsigned inputIndex, ExceptionState& exceptionState)
+{
+    ASSERT(isMainThread());
+    AudioContext::AutoLocker locker(context());
+
     // Sanity check input and output indices.
     if (outputIndex >= numberOfOutputs()) {
         exceptionState.throwDOMException(
             IndexSizeError,
-            "output index (" + String::number(outputIndex) + ") exceeds number of outputs (" + String::number(numberOfOutputs()) + ").");
-        return;
-    }
-
-    AudioNodeOutput* output = this->output(outputIndex);
-    output->disconnectAll();
+            ExceptionMessages::indexOutsideRange(
+                "output",
+                outputIndex,
+                0u,
+                ExceptionMessages::InclusiveBound,
+                numberOfOutputs(),
+                ExceptionMessages::InclusiveBound));
+        return;
+    }
+
+    if (inputIndex >= destination->numberOfInputs()) {
+        exceptionState.throwDOMException(
+            IndexSizeError,
+            ExceptionMessages::indexOutsideRange(
+                "input",
+                outputIndex,
+                0u,
+                ExceptionMessages::InclusiveBound,
+                destination->numberOfInputs(),
+                ExceptionMessages::InclusiveBound));
+        return;
+    }
+
+    AudioNodeOutput* output = this->output(outputIndex);
+    AudioNodeInput* input = destination->input(inputIndex);
+
+    // Sanity check on the connection between the output and the destination input.
+    if (!output->isConnectedToInput(*input)) {
+        exceptionState.throwDOMException(
+            InvalidAccessError,
+            "output (" + String::number(outputIndex) + ") is not connected to the input (" + String::number(inputIndex) + ") of the destination.");
+        return;
+    }
+
+    output->disconnectInput(*input);
+}
+
+void AudioNode::disconnect(AudioParam* destinationParam, ExceptionState& exceptionState)
+{
+    ASSERT(isMainThread());
+    AudioContext::AutoLocker locker(context());
+
+    unsigned numberOfDisconnections = 0;
+
+    for (unsigned i = 0; i < numberOfOutputs(); ++i) {
+        AudioNodeOutput* output = this->output(i);
+        if (output->isConnectedToAudioParam(*destinationParam)) {
+            output->disconnectAudioParam(*destinationParam);
+            numberOfDisconnections++;
+        }
+    }
+
+    // Throw an exception when there is no valid connection to the destination.
+    if (numberOfDisconnections == 0) {
+        exceptionState.throwDOMException(
+            InvalidAccessError,
+            "the node and the given AudioParam are not connected.");

[Raymond Toy, 2015/02/12 19:45:53]

Make this error message consistent with the error messages for similar
situations above.

[hongchan, 2015/02/13 01:16:57]

Done.

+        return;
+    }
+}
+
+void AudioNode::disconnect(AudioParam* destinationParam, unsigned outputIndex, ExceptionState& exceptionState)
+{
+    ASSERT(isMainThread());
+    AudioContext::AutoLocker locker(context());
+
+    // Sanity check on the output index.
+    if (outputIndex >= numberOfOutputs()) {
+        exceptionState.throwDOMException(
+            IndexSizeError,
+            ExceptionMessages::indexOutsideRange(
+                "output",
+                outputIndex,
+                0u,
+                ExceptionMessages::InclusiveBound,
+                numberOfOutputs(),
+                ExceptionMessages::InclusiveBound));
+        return;
+    }
+
+    AudioNodeOutput* output = this->output(outputIndex);
+
+    // Sanity check on the connection between the output and the destination.
+    if (!output->isConnectedToAudioParam(*destinationParam)) {
+        exceptionState.throwDOMException(
+            InvalidAccessError,
+            "specified destination AudioParam and node output (" + String::number(outputIndex) + ") are not connected.");
+        return;
+    }
+
+    output->disconnectAudioParam(*destinationParam);
 }
 
 void AudioNode::disconnectWithoutException(unsigned outputIndex)
 {
     ASSERT(isMainThread());
     AudioContext::AutoLocker locker(context());
 
     // Sanity check input and output indices.
     if (outputIndex < numberOfOutputs()) {
         AudioNodeOutput* output = this->output(outputIndex);
@@ skipping 298 matching lines @@
 
 void AudioNode::updateChannelCountMode()
 {
     m_channelCountMode = m_newChannelCountMode;
     updateChannelsForInputs();
 }
 
 } // namespace blink
 
 #endif // ENABLE(WEB_AUDIO)