Question

我无法使用采样器初始化和整体化音频图形而没有内存泄漏。我试图减少我的示例中的代码量，因此以下示例甚至不启动/停止图形。所以下面的代码并没有真正做任何有用的事情，但它不应该泄漏，是吗？

    AudioComponentDescription cd = {};
    cd.componentManufacturer     = kAudioUnitManufacturer_Apple;
    cd.componentFlags            = 0;
    cd.componentFlagsMask        = 0;

    AUGraph graph;
    AUNode sNode;
    AUNode IONode;
    // Instantiate an audio processing graph
    result = NewAUGraph (&graph); 

    //Specify the Sampler unit, to be used as the first node of the graph
    cd.componentType = kAudioUnitType_MusicDevice;
    cd.componentSubType = kAudioUnitSubType_Sampler;

    // THESE WOULDN'T CAUSE THE LEAK!!!
    // cd.componentType = kAudioUnitType_Effect;
    // cd.componentSubType = kAudioUnitSubType_HighPassFilter;

    // Add the Sampler unit node to the graph
    result = AUGraphAddNode (graph, &cd, &sNode);

    // Specify the Output unit, to be used as the second and final node of the graph
    cd.componentType = kAudioUnitType_Output;
    cd.componentSubType = kAudioUnitSubType_RemoteIO;

    // Add the Output unit node to the graph
    result = AUGraphAddNode (graph, &cd, &IONode);

    // Open the graph
    result = AUGraphOpen (graph);

    // Connect the Sampler unit to the output unit
    result = AUGraphConnectNodeInput (graph, sNode, 0, IONode, 0);

    // Initialize the audio processing graph.        
    result = AUGraphInitialize (graph);

    // Uninitialize
    result = AUGraphUninitialize(graph);

    CAShow(graph); // two nodes, 1 connection as expected


    AUGraphClearConnections(graph);
    AUGraphRemoveNode(graph, IONode);
    AUGraphRemoveNode(graph, sNode);

    CAShow(graph); // graph empty as expected

    result = DisposeAUGraph(graph);

    // -------> LEAK!

所有返回值都没问题，图表按预期工作，但我找不到内存泄漏的原因。这只发生在kAudioUnitSubType_Sampler上，而不是音频效果。

泄漏是48个字节，调用树看起来像这样（来自仪器中的Leaks-tool）：

0 libsystem_c.dylib calloc
1 libobjc.A.dylib class_createInstance
2 libdispatch.dylib _os_object_alloc
3 libdispatch.dylib dispatch_semaphore_create$VARIANT$up
4 AudioToolbox AudioStreamerImpl::Initialize()
5 AudioToolbox Sampler::Initialize()
6 AudioToolbox AUBase::DoInitialize()
7 AudioToolbox _ZL18AUMethodInitializePv
8 AudioToolbox AudioUnitNodeInfo::Initialize(AudioUnitGraph*)
9 AudioToolbox AudioUnitGraph::Initialize()
10 AudioToolbox AUGraphInitialize

泄漏的对象称为“OS_dispatch_semaphore”。我使用的是iOS 6.1，这种情况发生在模拟器以及iPhone 4和iPad 2中。任何想法导致泄漏？我一直试图追查原因几天，这真的让我疯狂：）

带采样器的AUGraph导致内存泄漏

0 个答案: