acm.c

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    add.cbStruct        = cbStruct;


    //
    //  for the current implementation of an ACM driver, the fccType and
    //  fccComp members *MUST* always be ACMDRIVERDETAILS_FCCTYPE_AUDIOACM
    //  ('audc') and ACMDRIVERDETAILS_FCCCOMP_UNDEFINED (0) respectively.
    //
    add.fccType         = ACMDRIVERDETAILS_FCCTYPE_AUDIOACM;
    add.fccComp         = ACMDRIVERDETAILS_FCCCOMP_UNDEFINED;


    //
    //  the manufacturer id (wMid) and product id (wPid) must be filled
    //  in with your company's _registered_ identifier's. for more
    //  information on these identifier's and how to get them registered
    //  contact G&G Lab and get the Multimedia Developer Registration Kit:
    //
    //      G&G Lab Corporation
    //      Multimedia Technology Group
    //      One G&G Lab Way
    //      Redmond, WA 98052-6399
    //
    //      Developer Services Phone: [phone] x11771
    //
    //  note that during the development phase or your ACM driver, you may
    //  use the reserved value of '0' for both wMid and wPid. however it
    //  is not acceptable to ship a driver with these values.
    //
    add.wMid            = MM_G&G LAB;
    add.wPid            = MM_MSFT_ACM_FILTALGORITH;


    //
    //  the vdwACM and vdwDriver members contain version information for
    //  the driver.
    //
    //  vdwACM: must contain the version of the *ACM* that the driver was
    //  _designed_ for. this is the _minimum_ version number of the ACM
    //  that the driver will work with. this value must be >= V2.00.000.
    //
    //  vdwDriver: the version of this ACM driver.
    //
    //  ACM driver versions are 32 bit numbers broken into three parts as
    //  follows (note these parts are displayed as decimal values):
    //
    //      bits 24 - 31:   8 bit _major_ version number
    //      bits 16 - 23:   8 bit _minor_ version number
    //      bits  0 - 15:   16 bit build number
    //
    add.vdwACM          = VERSION_MSACM;
    add.vdwDriver       = VERSION_ACM_DRIVER;


    //
    //  the following flags are used to specify the type of conversion(s)
    //  that the ACM driver supports. note that a driver may support one or
    //  more of these flags in any combination.
    //
    //  ACMDRIVERDETAILS_SUPPORTF_ACM: this flag is set if the driver 
    //  supports conversions from one format tag to another format tag. for
    //  example, if a converter compresses or decompresses WAVE_FORMAT_PCM
    //  and WAVE_FORMAT_IMA_ADPCM, then this bit should be set. this is
    //  true even if the data is not actually changed in size--for example
    //  a conversion from u-Law to A-Law will still set this bit because
    //  the format tags differ.
    //
    //  ACMDRIVERDETAILS_SUPPORTF_CONVERTER: this flags is set if the
    //  driver supports conversions on the same format tag. as an example,
    //  the PCM converter that is built into the ACM sets this bit (and only
    //  this bit) because it converts only between PCM formats (bits, sample
    //  rate).
    //
    //  ACMDRIVERDETAILS_SUPPORTF_FILTER: this flag is set if the driver 
    //  supports transformations on a single format tag but does change
    //  the base characteristics of the format (bit depth, sample rate, etc
    //  will remain the same). for example, a driver that changed the
    //  'volume' of PCM data or applied a low pass filter would set this bit.
    //
    add.fdwSupport      = ACMDRIVERDETAILS_SUPPORTF_FILTER;


    //
    //  the number of individual format tags this ACM driver supports. for
    //  example, if a driver uses the WAVE_FORMAT_IMA_ADPCM and
    //  WAVE_FORMAT_PCM format tags, then this value would be two. if the
    //  driver only supports filtering on WAVE_FORMAT_PCM, then this value
    //  would be one. if this driver supported WAVE_FORMAT_ALAW,
    //  WAVE_FORMAT_MULAW and WAVE_FORMAT_PCM, then this value would be
    //  three. etc, etc.
    //
    add.cFormatTags     = ACM_DRIVER_MAX_FORMAT_TAGS;

    //
    //  the number of individual filter tags this ACM driver supports. if
    //  a driver supports no filters (ACMDRIVERDETAILS_SUPPORTF_FILTER is
    //  NOT set in the fdwSupport member), then this value must be zero.
    //
    add.cFilterTags     = ACM_DRIVER_MAX_FILTER_TAGS;


    //
    //  the remaining members in the ACMDRIVERDETAILS structure are sometimes
    //  not needed. because of this we make a quick check to see if we
    //  should go through the effort of filling in these members.
    //
    if (FIELD_OFFSET(ACMDRIVERDETAILS, hicon) < cbStruct)
    {
        //
        //  fill in the hicon member will a handle to a custom icon for
        //  the ACM driver. this allows the driver to be represented by
        //  an application graphically (usually this will be a company
        //  logo or something). if a driver does not wish to have a custom
        //  icon displayed, then simply set this member to NULL and a
        //  generic icon will be displayed instead.
        //
        add.hicon = LoadIcon(pdi->hinst, ICON_ACM_DRIVER);

        //
        //  the short name and long name are used to represent the driver
        //  in a unique description. the short name is intended for small
        //  display areas (for example, in a menu or combo box). the long
        //  name is intended for more descriptive displays (for example,
        //  in an 'about box').
        //
        //  NOTE! an ACM driver should never place formatting characters
        //  of any sort in these strings (for example CR/LF's, etc). it
        //  is up to the application to format the text.
        //
    	LoadStringACM(pdi->hinst, IDS_ACM_DRIVER_SHORTNAME, add.szShortName, SIZEOFACMSTR(add.szShortName));
        LoadStringACM(pdi->hinst, IDS_ACM_DRIVER_LONGNAME,  add.szLongName,  SIZEOFACMSTR(add.szLongName));

        //
        //  the last three members are intended for 'about box' information.
        //  these members are optional and may be zero length strings if
        //  the driver wishes.
        //
        //  NOTE! an ACM driver should never place formatting characters
        //  of any sort in these strings (for example CR/LF's, etc). it
        //  is up to the application to format the text.
        //
        if (FIELD_OFFSET(ACMDRIVERDETAILS, szCopyright) < cbStruct)
        {
            LoadStringACM(pdi->hinst, IDS_ACM_DRIVER_COPYRIGHT, add.szCopyright, SIZEOFACMSTR(add.szCopyright));
            LoadStringACM(pdi->hinst, IDS_ACM_DRIVER_LICENSING, add.szLicensing, SIZEOFACMSTR(add.szLicensing));
            LoadStringACM(pdi->hinst, IDS_ACM_DRIVER_FEATURES,  add.szFeatures,  SIZEOFACMSTR(add.szFeatures));
        }
    }


    //
    //  now copy the correct number of bytes to the caller's buffer
    //
    _fmemcpy(padd, &add, (UINT)add.cbStruct);


    //
    //  success!
    //
    return (MMSYSERR_NOERROR);
} // acmdDriverDetails()


//--------------------------------------------------------------------------;
//
//  INT_PTR acmdDlgProcAbout
//
//  Description:
//
//      This dialog procedure is used for the ubiquitous about box.
//
//      Note that we need to create a brush and store the handle between
//      messages.  In order to avoid using global memory, we store the
//      handle to this brush in the Window structure using the DWLP_USER
//      index.
//
//  Arguments:
//      HWND hwnd: Handle to window.
//
//      UINT uMsg: Message being sent to the window.
//
//      WPARAM wParam: Specific argument to message.
//
//      LPARAM lParam: Specific argument to message.
//
//  Return (INT_PTR):
//      The return value is specific to the message that was received. For
//      the most part, it is FALSE if this dialog procedure does not handle
//      a message.  Note, however, that we must return an HBRUSH for Windows
//      to use for painting the background for the WM_CTLCOLORxxx messages.
//
//
//--------------------------------------------------------------------------;

#define ABOUT_BACKGROUNDCOLOR                   RGB(128,128,128)
#define ABOUT_HILIGHTCOLOR                      RGB(0,255,255)

INT_PTR FNEXPORT acmdDlgProcAbout
(
    HWND                    hwnd,
    UINT                    uMsg,
    WPARAM                  wParam,
    LPARAM                  lParam
)
{
    HBRUSH      hbr;
    HWND        hctrl;
    UINT        u;


    hbr = (HBRUSH)GetWindowLongPtr( hwnd, DWLP_USER );

    switch (uMsg)
    {
        case WM_INITDIALOG:
            hbr = CreateSolidBrush( ABOUT_BACKGROUNDCOLOR );
            SetWindowLongPtr( hwnd, DWLP_USER, (LONG_PTR)hbr );
            return TRUE;

        case WM_CTLCOLORSTATIC:
            hctrl = GetDlgItem( hwnd, IDC_ABOUT_CATCHTHEWAVE );
            if( (HWND)lParam == hctrl )
            {
                SetTextColor( (HDC)wParam, ABOUT_HILIGHTCOLOR );
            }
            // Fall through...

        case WM_CTLCOLORDLG:
        case WM_CTLCOLORBTN:
            SetBkColor( (HDC)wParam, ABOUT_BACKGROUNDCOLOR );
            return (INT_PTR)hbr;

        case WM_COMMAND:
            u = GET_WM_COMMAND_ID(wParam, lParam);
            if ((IDOK == u) || (IDCANCEL == u))
            {
                EndDialog(hwnd, (IDOK == u));
            }
            return FALSE;

        case WM_DESTROY:
            DeleteObject( hbr );
            return FALSE;
    }

    return (FALSE);
} // acmdDlgProcAbout()


//--------------------------------------------------------------------------;
//
//  LRESULT acmdDriverAbout
//
//  Description:
//      This function is called to handle the ACMDM_DRIVER_ABOUT message.
//      An ACM driver has the option of displaying its own 'about box' or
//      letting the ACM (or calling application) display one for it. This
//      message is normally sent by the Control Panel's Sound Mapper
//      option.
//
//      It is recommended that an ACM driver allow a default about box
//      be displayed for it--there should be no reason to bloat the size
//      of a driver to simply display copyright, etc information when that
//      information is contained in the ACMDRIVERDETAILS structure.
//
//  Arguments:
//      PDRIVERINSTANCE pdi: Pointer to private ACM driver instance structure.
//      This structure is [optionally] allocated during the DRV_OPEN message
//      which is handled by the acmdDriverOpen function.
//
//      HWND hwnd: Handle to parent window to use when displaying the
//      Configururation dialog box. An ACM driver is _required_ to display a
//      modal dialog box using this hwnd argument as the parent. This
//      argument may be (HWND)-1 which tells the driver that it is only
//      being queried for about box support.
//
//  Return (LRESULT):
//      The return value is MMSYSERR_NOTSUPPORTED if the ACM driver does
//      not support a custom dialog box. In this case, the ACM or calling
//      application will display a generic about box using the information
//      contained in the ACMDRIVERDETAILS structure returned by the
//      ACMDM_DRIVER_DETAILS message.
//
//      If the driver chooses to display its own dialog box, then after
//      the dialog is dismissed by the user, MMSYSERR_NOERROR should be
//      returned.
//
//      If the hwnd argument is equal to (HWND)-1, then no dialog should
//      be displayed (the driver is only being queried for support). The
//      driver must still return MMSYSERR_NOERROR (supported) or  
//      MMSYSERR_NOTSUPPORTED (no custom about box supported).
//
//--------------------------------------------------------------------------;

LRESULT FNLOCAL acmdDriverAbout
(
    PDRIVERINSTANCE         pdi,
    HWND                    hwnd
)
{
    //
    //  first check to see if we are only being queried for custom about
    //  box support. if hwnd == (HWND)-1 then we are being queried and
    //  should return MMSYSERR_NOTSUPPORTED for 'not supported' and
    //  MMSYSERR_NOERROR for 'supported'.
    //
    if ((HWND)-1 == hwnd)
    {
        //
        //  this ACM driver supports a custom about box, so
        //  return MMSYSERR_NOERROR...
        //
        return (MMSYSERR_NOERROR);
    }


    //
    //  this driver does support a custom dialog, so display it.  Note,
    //  however, that it is better to let the ACM display the About box
    //  for us - that means smaller code, and fewer bugs!
    //
    DialogBox( pdi->hinst, IDD_ABOUT, hwnd, acmdDlgProcAbout );

    return (MMSYSERR_NOERROR);
} // acmdDriverAbout()


//==========================================================================;
//
//
//
//
//==========================================================================;

//--------------------------------------------------------------------------;
//  
//  LRESULT acmdFormatTagDetails
//  
//  Description:
//      This function handles the ACMDM_FORMATTAG_DETAILS message. This
//      message is normally sent in response to an acmFormatTagDetails or
//      acmFormatTagEnum function call. The purpose of this function is
//      to get details about a specific format tag supported by this ACM
//      driver.
//  
//  Arguments:
//      PDRIVERINSTANCE pdi: Pointer to private ACM driver instance structure.
//      This structure is [optionally] allocated during the DRV_OPEN message
//      which is handled by the acmdDriverOpen function.
//
//      LPACMFORMATTAGDETAILS padft: Pointer to an ACMFORMATTAGDETAILS
//      structure that describes what format tag to retrieve details for.
//
//      DWORD fdwDetails: Flags defining what format tag to retrieve the
//      details for.
//  
//  Return (LRESULT):
//      The return value is zero (MMSYSERR_NOERROR) if this function
//      succeeds with no errors. The return value is a non-zero error code
//      if the function fails.
//
//      The driver should return MMSYSERR_NOTSUPPORTED if the query type
//      specified in fdwDetails is not supported. An ACM driver must
//      support at least the following query types:
//
//      ACM_FORMATTAGDETAILSF_INDEX: Indicates that a format tag index
//      was given in the dwFormatTagIndex member of the ACMFORMATTAGDETAILS
//      structure. The format tag and details must be returned in the
//      structure specified by padft. The index ranges from zero to one less
//      than the cFormatTags member returned in the ACMDRIVERDETAILS
//      structure for this driver.
//
//      ACM_FORMATTAGDETAILSF_FORMATTAG: Indicates that a format tag
//      was given in the dwFormatTag member of the ACMFORMATTAGDETAILS
//      structure. The format tag details must be returned in the structure
//      specified by padft.
//
//      ACM_FORMATTAGDETAILSF_LARGESTSIZE: Indicates that the details
//      on the format tag with the largest format size in bytes must be
//      returned. The dwFormatTag member will either be WAVE_FORMAT_UNKNOWN
//      or the format tag to find the largest size for.
//
//      If the details for the specified format tag cannot be retrieved
//      from this driver, then ACMERR_NOTPOSSIBLE should be returned.
//
//--------------------------------------------------------------------------;

LRESULT FNLOCAL acmdFormatTagDetails
(
    PDRIVERINSTANCE         pdi,
    LPACMFORMATTAGDETAILS   padft,
    DWORD                   fdwDetails