自动挂机麦克风录音测试

要则试麦克风重复打开关闭的功能，如果手动也太麻烦了。
为了让打开关闭的时间更随机一点，使用WASAPI做了这么一个小功能。

#include <iostream>
#include <Shlwapi.h>
#include <MMDeviceAPI.h>
#include <AudioClient.h>

#define SAFE_RELEASE(punk)  \
              if ((punk) != NULL)  \
                { (punk)->Release(); (punk) = NULL; }

void MicTest(ULONGLONG EndTieme)
{
    IMMDeviceEnumerator* deviceEnumerator = NULL;
    HRESULT hr = CoCreateInstance(__uuidof(MMDeviceEnumerator), NULL, CLSCTX_INPROC_SERVER, IID_PPV_ARGS(&deviceEnumerator));
    if (FAILED(hr)) 
    {
        printf("Unable to retrieve CoCreateInstance %x\n", hr);
        return;
    }

    IAudioClient* _AudioClient;
    IAudioCaptureClient* _CaptureClient;
    IMMDevice* _Device;

    hr = deviceEnumerator->GetDefaultAudioEndpoint(eCapture, eMultimedia, &_Device);
    if (FAILED(hr))
    {
        printf("Unable to retrieve device %x\n", hr);
        return;
    }


    HANDLE _AudioSamplesReadyEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
    if (_AudioSamplesReadyEvent == NULL)
    {
        printf("Unable to create samples ready event: %d.\n", GetLastError());
        return;
    }

    hr = _Device->Activate(__uuidof(IAudioClient), CLSCTX_INPROC_SERVER, NULL, reinterpret_cast<void**>(&_AudioClient));
    if (FAILED(hr))
    {
        printf("Unable to activate audio client: %x.\n", hr);
        return;
    }

    WAVEFORMATEX* _MixFormat;
    hr = _AudioClient->GetMixFormat(&_MixFormat);
    if (FAILED(hr))
    {
        printf("Unable to get mix format on audio client: %x.\n", hr);
        return ;
    }

    REFERENCE_TIME hnsDefaultDevicePeriod;
    hr = _AudioClient->GetDevicePeriod(&hnsDefaultDevicePeriod, NULL);
    if (FAILED(hr)) 
    {
        return ;
    }

    hr = _AudioClient->Initialize(AUDCLNT_SHAREMODE_SHARED,AUDCLNT_STREAMFLAGS_EVENTCALLBACK, hnsDefaultDevicePeriod, hnsDefaultDevicePeriod, _MixFormat, NULL);
    if (FAILED(hr))
    {
        printf("Unable to initialize audio client: %x.\n", hr);
        return ;
    }

    UINT32              _BufferSize;
    hr = _AudioClient->GetBufferSize(&_BufferSize);
    if (FAILED(hr))
    {
        printf("Unable to get audio client buffer: %x. \n", hr);
        return ;
    }

    hr = _AudioClient->SetEventHandle(_AudioSamplesReadyEvent);
    if (FAILED(hr))
    {
        printf("Unable to set ready event: %x.\n", hr);
        return ;
    }

    hr = _AudioClient->GetService(IID_PPV_ARGS(&_CaptureClient));
    if (FAILED(hr))
    {
        printf("Unable to get new capture client: %x.\n", hr);
        return ;
    }

    hr = _AudioClient->Reset();
    if (FAILED(hr))
    {
        printf("Unable to get new capture client: %x.\n", hr);
        return ;
    }

    hr = _AudioClient->Start();
    if (FAILED(hr))
    {
        printf("Unable to get new capture client: %x.\n", hr);
        return ;
    }

    while (GetTickCount64() < EndTieme)
    {
        DWORD waitResult = WaitForSingleObject(_AudioSamplesReadyEvent, INFINITE);
        BYTE* pData;
        UINT32 framesAvailable;
        DWORD  flags;

        hr = _CaptureClient->GetBuffer(&pData, &framesAvailable, &flags, NULL, NULL);
        if (SUCCEEDED(hr))
        {
            hr = _CaptureClient->ReleaseBuffer(framesAvailable);
            if (FAILED(hr))
            {
                printf("Unable to release capture buffer: %x!\n", hr);
            }
        }
    }

    hr = _AudioClient->Stop();

    CloseHandle(_AudioSamplesReadyEvent);
    SAFE_RELEASE(deviceEnumerator);
    SAFE_RELEASE(_Device);
    SAFE_RELEASE(_AudioClient);
    SAFE_RELEASE(_CaptureClient);

}
int main()
{
    CoInitializeEx(NULL, COINIT_MULTITHREADED);
    for(int i=0;;i++)
    {
        ULONG range = rand() % 100000;
        ULONGLONG EndTime = GetTickCount64() + range;
        printf("%d %dms test\n", i, range);
        MicTest(EndTime);

    }
    return 0;
}