DSENUM.C

/*========================================================================== 
 * 
 *  Copyright (C) 1995-1997 Microsoft Corporation. All Rights Reserved. 
 * 
 *  File:   dstrenum.c 
 *  Content:   Illustrates enumerating DirectSound drivers 
 * 
 ***************************************************************************/ 
#define WIN32_LEAN_AND_MEAN 
#include <windows.h> 
#include <windowsx.h> 
#include <mmsystem.h> 
#include <dsound.h> 
#include <memory.h> 
 
#include "dsenum.h" 
#include "resource.h" 
 
extern HINSTANCE hInst; 
extern HWND      hWndMain; 
 
 
 
/****************************************************************************/ 
/* DoDSoundEnumerate()                                                      */ 
/*                                                                          */ 
/*   This function takes care of handling the DirectSound enumeration, which*/ 
/* simply means creating a dialog box, at this point...                     */ 
/****************************************************************************/ 
BOOL DoDSoundEnumerate( LPGUID lpGUID ) 
    { 
    if( DialogBoxParam( hInst, MAKEINTRESOURCE(IDD_DSENUMBOX), hWndMain, 
                        DSEnumDlgProc, (LPARAM)lpGUID )) 
        return( TRUE ); 
 
    return( FALSE ); 
    } 
 
/****************************************************************************/ 
/* DSEnumDlgProc()                                                          */ 
/*                                                                          */ 
/*   Dialog procedure for the DSound enumeration choice dialog. Allows the  */ 
/* user to choose from installed drivers.  Returns TRUE on error.           */ 
/****************************************************************************/ 
BOOL CALLBACK DSEnumDlgProc( HWND hDlg, UINT msg, 
                                WPARAM wParam, LPARAM lParam ) 
    { 
    static HWND   hCombo; 
    static LPGUID lpGUID; 
    LPGUID        lpTemp; 
    int           i; 
 
    switch( msg ) 
        { 
        case WM_INITDIALOG: 
            hCombo = GetDlgItem( hDlg, IDC_DSENUM_COMBO ); 
            lpGUID = (LPGUID)lParam; 
 
            if( DirectSoundEnumerate( (LPDSENUMCALLBACK)DSEnumProc, &hCombo ) != DS_OK ) 
                { 
                EndDialog( hDlg, TRUE ); 
                return( TRUE ); 
                } 
            if( ComboBox_GetCount( hCombo )) 
                ComboBox_SetCurSel( hCombo, 0 ); 
            else 
                { 
                EndDialog( hDlg, TRUE ); 
                return( TRUE ); 
                } 
            return( TRUE ); 
 
 
        case WM_COMMAND: 
            switch( LOWORD( wParam )) 
                { 
                case IDOK: 
                    for( i = 0; i < ComboBox_GetCount( hCombo ); i++ ) 
                        { 
                        lpTemp = (LPGUID)ComboBox_GetItemData( hCombo, i ); 
                        if( i == ComboBox_GetCurSel( hCombo )) 
                            { 
                            if( lpTemp != NULL ) 
                                memcpy( lpGUID, lpTemp, sizeof(GUID)); 
    else 
        lpGUID = NULL; 
    } 
                        if( lpTemp ) 
                            LocalFree( lpTemp ); 
                        } 
                    // If we got the NULL GUID, then we want to open the default 
                    // sound driver, so return with an error and the init code 
    // will know not to pass in the guID and will send NULL 
    // instead. 
                    if( lpGUID == NULL ) 
        EndDialog( hDlg, TRUE ); 
                    else 
                        EndDialog( hDlg, FALSE ); 
                    return( TRUE ); 
 
                case IDCANCEL: 
                    // Force a NULL GUID 
                    EndDialog( hDlg, TRUE ); 
                    return( TRUE ); 
                } 
            break; 
 
 
        default: 
            return( FALSE ); 
        } 
 
    return( FALSE ); 
    } 
 
 
/****************************************************************************/ 
/* DSEnumProc()                                                             */ 
/*                                                                          */ 
/*   This is the Enumeration procedure called by DirectSoundEnumerate with  */ 
/* the parameters of each DirectSound Object available in the system.       */ 
/****************************************************************************/ 
BOOL CALLBACK DSEnumProc( LPGUID lpGUID, LPSTR lpszDesc, 
                                LPSTR lpszDrvName, LPVOID lpContext ) 
    { 
    HWND   hCombo = *(HWND *)lpContext; 
    LPGUID lpTemp = NULL; 
 
    if( lpGUID != NULL ) 
        { 
        if(( lpTemp = LocalAlloc( LPTR, sizeof(GUID))) == NULL ) 
    return( TRUE ); 
 
        memcpy( lpTemp, lpGUID, sizeof(GUID)); 
} 
 
    ComboBox_AddString( hCombo, lpszDesc ); 
    ComboBox_SetItemData( hCombo, 
    ComboBox_FindString( hCombo, 0, lpszDesc ), 
    lpTemp ); 
    return( TRUE ); 
    }