Bug 865650 - Ensure that looping will only happen if the start offset is less than the end offset; r=padenot

Ehsan Akhgari · Ehsan Akhgari · commit ce979bfbded5 · 2013-04-25T09:34:47.000-04:00
--HG--
extra : rebase_source : 3de31185083df174f7b6e823d1a135aee39c211d
diff --git a/content/media/webaudio/AudioBufferSourceNode.cpp b/content/media/webaudio/AudioBufferSourceNode.cpp
@@ -562,8 +562,6 @@ AudioBufferSourceNode::SendDopplerShiftToStream(double aDopplerShift)
 void
 AudioBufferSourceNode::SendLoopParametersToStream()
 {
-  SendInt32ParameterToStream(LOOP, mLoop ? 1 : 0);
-
   // Don't compute and set the loop parameters unnecessarily
   if (mLoop && mBuffer) {
     float rate = mBuffer->SampleRate();
@@ -580,8 +578,13 @@ AudioBufferSourceNode::SendLoopParametersToStream()
     }
     int32_t loopStartTicks = NS_lround(actualLoopStart * rate);
     int32_t loopEndTicks = NS_lround(actualLoopEnd * rate);
-    SendInt32ParameterToStream(LOOPSTART, loopStartTicks);
-    SendInt32ParameterToStream(LOOPEND, loopEndTicks);
+    if (loopStartTicks < loopEndTicks) {
+      SendInt32ParameterToStream(LOOPSTART, loopStartTicks);
+      SendInt32ParameterToStream(LOOPEND, loopEndTicks);
+      SendInt32ParameterToStream(LOOP, 1);
+    }
+  } else if (!mLoop) {
+    SendInt32ParameterToStream(LOOP, 0);
   }
 }
 
diff --git a/content/media/webaudio/test/Makefile.in b/content/media/webaudio/test/Makefile.in
@@ -25,6 +25,7 @@ MOCHITEST_FILES := \
   test_audioBufferSourceNode.html \
   test_audioBufferSourceNodeLoop.html \
   test_audioBufferSourceNodeLoopStartEnd.html \
+  test_audioBufferSourceNodeLoopStartEndSame.html \
   test_audioBufferSourceNodeNullBuffer.html \
   test_badConnect.html \
   test_biquadFilterNode.html \
diff --git a/content/media/webaudio/test/test_audioBufferSourceNodeLoopStartEndSame.html b/content/media/webaudio/test/test_audioBufferSourceNodeLoopStartEndSame.html
@@ -0,0 +1,44 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test AudioBufferSourceNode looping</title>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="webaudio.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+SimpleTest.waitForExplicitFinish();
+addLoadEvent(function() {
+  SpecialPowers.setBoolPref("media.webaudio.enabled", true);
+
+  var context = new AudioContext();
+  var buffer = context.createBuffer(1, 0, context.sampleRate);
+
+  var expectedBuffer = context.createBuffer(1, 2048, context.sampleRate);
+
+  var source = context.createBufferSource();
+  source.buffer = buffer;
+
+  var sp = context.createScriptProcessor(2048, 1);
+  source.loop = true;
+  source.start(0);
+  source.connect(sp);
+  sp.connect(context.destination);
+  sp.onaudioprocess = function(e) {
+    is(e.inputBuffer.numberOfChannels, 1, "input buffer must have only one channel");
+    compareBuffers(e.inputBuffer.getChannelData(0), expectedBuffer.getChannelData(0));
+
+    sp.onaudioprocess = null;
+
+    SpecialPowers.clearUserPref("media.webaudio.enabled");
+    SimpleTest.finish();
+  };
+});
+
+</script>
+</pre>
+</body>
+</html>

Original file line number	Diff line number	Diff line change
`@@ -562,8 +562,6 @@ AudioBufferSourceNode::SendDopplerShiftToStream(double aDopplerShift)`
`562`	`562`	`void`
`563`	`563`	`AudioBufferSourceNode::SendLoopParametersToStream()`
`564`	`564`	`{`
`565`		`- SendInt32ParameterToStream(LOOP, mLoop ? 1 : 0);`
`566`		`-`
`567`	`565`	`// Don't compute and set the loop parameters unnecessarily`
`568`	`566`	`if (mLoop && mBuffer) {`
`569`	`567`	`float rate = mBuffer->SampleRate();`
`@@ -580,8 +578,13 @@ AudioBufferSourceNode::SendLoopParametersToStream()`
`580`	`578`	`}`
`581`	`579`	`int32_t loopStartTicks = NS_lround(actualLoopStart * rate);`
`582`	`580`	`int32_t loopEndTicks = NS_lround(actualLoopEnd * rate);`
`583`		`- SendInt32ParameterToStream(LOOPSTART, loopStartTicks);`
`584`		`- SendInt32ParameterToStream(LOOPEND, loopEndTicks);`
	`581`	`+ if (loopStartTicks < loopEndTicks) {`
	`582`	`+ SendInt32ParameterToStream(LOOPSTART, loopStartTicks);`
	`583`	`+ SendInt32ParameterToStream(LOOPEND, loopEndTicks);`
	`584`	`+ SendInt32ParameterToStream(LOOP, 1);`
	`585`	`+ }`
	`586`	`+ } else if (!mLoop) {`
	`587`	`+ SendInt32ParameterToStream(LOOP, 0);`
`585`	`588`	`}`
`586`	`589`	`}`
`587`	`590`