windows-server-2003/drivers/wdm/capture/mini/atiwdm/atishare/registry.cpp

//==========================================================================;
//
//  Registry.CPP
//  WDM MiniDrivers development.
//      Global space.
//          Registry data management.
//  Copyright (c) 1996 - 1997  ATI Technologies Inc.  All Rights Reserved.
//
//      $Date:   15 Apr 1999 11:08:06  $
//  $Revision:   1.6  $
//    $Author:   Tashjian  $
//
//==========================================================================;

#include "common.h"

#include "registry.h"


ULONG   g_DebugLevel;
PCHAR   g_DebugComponent = WDM_DRIVER_NAME " not set in registry: ";


/*^^*
 *      OpenRegistryFolder()
 * Purpose  : Gets the specified Registry folder handle ( opens the folder) to be used later on
 *
 * Inputs   : PDEVICE_OBJECT pDeviceObject  : pointer to DeviceObject
 *            PWCHAR pwchFolderName         : name of the Registry folder to open, might be NULL
 * Outputs  : HANDLE, NULL if the Registry folder has not been opened
 * Author   : IKLEBANOV
 *^^*/
HANDLE OpenRegistryFolder( PDEVICE_OBJECT pDeviceObject, PWCHAR pwchFolderName)
{
    HANDLE              hFolder, hDevice;
    NTSTATUS            ntStatus;
    UNICODE_STRING      FolderName;
    OBJECT_ATTRIBUTES   attr;

    hFolder = hDevice = NULL;

    ENSURE
    {
        ntStatus = ::IoOpenDeviceRegistryKey( pDeviceObject,
                                              PLUGPLAY_REGKEY_DRIVER, STANDARD_RIGHTS_ALL,
                                              &hDevice);

        if( !NT_SUCCESS( ntStatus) || ( hDevice == NULL))
            FAIL;

        if( pwchFolderName != NULL)
        {
            ::RtlInitUnicodeString( &FolderName, pwchFolderName);
            InitializeObjectAttributes( &attr, &FolderName, OBJ_INHERIT|OBJ_KERNEL_HANDLE, hDevice, NULL);

            ntStatus = ::ZwOpenKey( &hFolder, KEY_QUERY_VALUE, &attr);
            ::ZwClose( hDevice);

            if( !NT_SUCCESS( ntStatus)) 
                FAIL;
        }
        else
            hFolder = hDevice;

        return( hFolder);

    } END_ENSURE;

    return( NULL);
}



/*^^*
 *      SetMiniDriverDebugLevel()
 * Purpose  : Sets the Debugging level required by user
 *
 * Inputs   : PUNICODE_STRING pRegistryPath : MiniDriver's private Registry path
 * Outputs  : none
 *
 * Author   : IKLEBANOV
 *^^*/
extern "C"
void SetMiniDriverDebugLevel( PUNICODE_STRING pRegistryPath)
{
    OBJECT_ATTRIBUTES   objectAttributes;
    HANDLE              hFolder;
    ULONG               ulValue;
    WCHAR               wcDriverName[20];

    // Set the default value as no Debug
    g_DebugLevel = 0;

    InitializeObjectAttributes( &objectAttributes, 
                                pRegistryPath, 
                                OBJ_CASE_INSENSITIVE, 
                                NULL, 
                                NULL); 

    if( NT_SUCCESS( ZwOpenKey( &hFolder, KEY_READ, &objectAttributes)))
    {
        ulValue = 0;

        if( NT_SUCCESS( ReadStringFromRegistryFolder( hFolder,
                                                      UNICODE_WDM_DEBUGLEVEL_INFO,
                                                      ( PWCHAR)&ulValue,
                                                      sizeof( ULONG))))
            g_DebugLevel = ulValue;

        // fetch the driver name from the registry
        if( NT_SUCCESS( ReadStringFromRegistryFolder( hFolder,
                                                      UNICODE_WDM_DRIVER_NAME,
                                                      wcDriverName,
                                                      sizeof(wcDriverName)))) {

            // set g_DebugComponent by using driver name
            ANSI_STRING     stringDriverName;
            UNICODE_STRING  unicodeDriverName;

            // convert unicode driver name to ansi
            RtlInitAnsiString(&stringDriverName, g_DebugComponent);
            RtlInitUnicodeString(&unicodeDriverName, wcDriverName);
            RtlUnicodeStringToAnsiString(&stringDriverName, &unicodeDriverName, FALSE);

            // remove extension and put a colon 
            PCHAR pExt = strchr(g_DebugComponent, '.');
            if (pExt) {
                *pExt++ = ':';
                *pExt++ = ' ';
                *pExt   = 0;
            }

            // convert to upper case (or lower case... whatever your fancy)
            //_strupr(g_DebugComponent);  
            //_strlwr(g_DebugComponent);  
        }
        ZwClose( hFolder);
    }

}



/*^^*
 *      ReadStringFromRegistryFolder
 * Purpose  : Read ASCII string from the Registry folder
 *
 * Inputs   : HANDLE hFolder            : Registry folder handle to read the values from
 *            PWCHAR pwcKeyNameString   : pointer to the StringValue to read
 *            PWCHAR pwchBuffer         : pointer to the buffer to read into
 *            ULONG ulDataLength        : length of the data to be expected to read
 *
 * Outputs  : NTSTATUS of the registry read operation
 * Author   : IKLEBANOV
 *^^*/
NTSTATUS ReadStringFromRegistryFolder( HANDLE hFolder, PWCHAR pwcKeyNameString, PWCHAR pwchBuffer, ULONG ulDataLength)
{
    NTSTATUS                    ntStatus = STATUS_UNSUCCESSFUL;
    UNICODE_STRING              unicodeKeyName;
    ULONG                       ulLength;
    PKEY_VALUE_FULL_INFORMATION FullInfo;

    ENSURE 
    {
        ::RtlInitUnicodeString( &unicodeKeyName, pwcKeyNameString);

        ulLength = sizeof( KEY_VALUE_FULL_INFORMATION) + unicodeKeyName.MaximumLength + ulDataLength;

        FullInfo = ( PKEY_VALUE_FULL_INFORMATION)::ExAllocatePool( PagedPool, ulLength);

        if( FullInfo) 
        {
            ntStatus = ::ZwQueryValueKey( hFolder,
                                          &unicodeKeyName,
                                          KeyValueFullInformation,
                                          FullInfo,
                                          ulLength,
                                          &ulLength);

            if( NT_SUCCESS( ntStatus)) 
            {
                if( ulDataLength >= FullInfo->DataLength) 
                    RtlCopyMemory( pwchBuffer, (( PUCHAR)FullInfo) + FullInfo->DataOffset, FullInfo->DataLength);
                else 
                {
                    TRAP;
                    ntStatus = STATUS_BUFFER_TOO_SMALL;
                } // buffer right length

            } // if success

            ::ExFreePool( FullInfo);
        }
        else
        {
            ntStatus = STATUS_NO_MEMORY;
        }

    } END_ENSURE;

    return( ntStatus);
}