windows-xp/Source/XPSP1/NT/termsrv/tsuserex/registry.cpp

/*--------------------------------------------------------------------------------------------------------
*  Copyright (c) 1998  Microsoft Corporation
*
*  Module Name:
*
*      Registry.cpp
*
*  Abstract:
*
*      Registry.cpp: implementation of the CRegistry class.
*      This class helps with registry by allocating memory by itself
*      As a result caller must copy the pointer returned by Get functions
*      immediately.
*
*
*
*  Author:
*
*      Makarand Patwardhan  - April 9, 1997
*
* -------------------------------------------------------------------------------------------------------*/

#include "stdafx.h"
#include "Registry.h"


/*--------------------------------------------------------------------------------------------------------
* Constructor
* -------------------------------------------------------------------------------------------------------*/
CRegistry::CRegistry()
{
    m_pMemBlock = NULL;
    m_hKey = NULL;
    m_iEnumIndex = -1;
    m_iEnumValueIndex = -1;

#ifdef DBG
    m_dwSizeDebugOnly = 0;
#endif
}

/*--------------------------------------------------------------------------------------------------------
* Destructor
* -------------------------------------------------------------------------------------------------------*/
CRegistry::~CRegistry()
{
    if (m_hKey != NULL)
    {
        RegCloseKey(m_hKey);
        m_hKey = NULL;
    }
    Release();
}

/*--------------------------------------------------------------------------------------------------------
* void Allocate (DWORD dwSize)
* This private function is used for allocating the memory for 
* reading registry
* returns the pointer to memory allocated.
* -------------------------------------------------------------------------------------------------------*/
void *CRegistry::Allocate (DWORD dwSize)
{
    ASSERT(dwSize != 0);
    if (m_pMemBlock)
        Release();
    
    m_pMemBlock = new BYTE[dwSize];

#ifdef DBG
    // remember the size of the block to be allocated.
    m_dwSizeDebugOnly = dwSize;
#endif

    return m_pMemBlock;
}

/*--------------------------------------------------------------------------------------------------------
* void Release ()
* This private function is used for releasing internal memory block
* -------------------------------------------------------------------------------------------------------*/
void CRegistry::Release ()
{
    if (m_pMemBlock)
    {

#ifdef DBG
        // fistly fill up the block we allocated previously with garbage.
        // so that if anybody is using this block, it is more lilely to 
        // catch the bug.
        ASSERT(m_dwSizeDebugOnly != 0);
        FillMemory(m_pMemBlock, m_dwSizeDebugOnly, 'c');
        m_dwSizeDebugOnly = 0;

#endif

        delete [] m_pMemBlock;
    }
    
    m_pMemBlock = 0;
}


/*--------------------------------------------------------------------------------------------------------
* DWORD CRegistry::CreateKey(HKEY hKey, LPCTSTR lpSubKey, REGSAM access = KEY_ALL_ACCESS, DWORD *pDisposition = NULL)
* opens/creates the key specified. before attempting any operation on any key/value. this function
* must be called.
* hKey - hive
* lpSubKey - Path of the key in the format _T("SYSTEM\\CurrentControlSet\\Control\\Terminal Server")
* access - access desired. like REG_READ, REG_WRITE..
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::CreateKey(HKEY hKey, LPCTSTR lpSubKey, REGSAM access /*= KEY_ALL_ACCESS*/, DWORD *pDisposition /*= NULL*/)
{
    ASSERT(lpSubKey);
    ASSERT(*lpSubKey != '\\');

    if (m_hKey != NULL)
    {
        RegCloseKey(m_hKey);
        m_hKey = NULL;
    }

    DWORD dwDisposition;
    LONG lResult = RegCreateKeyEx( 
                    hKey,               // handle of an open key 
                    lpSubKey,           // address of subkey name 
                    0,                  // reserved 
                    NULL,               // address of class string 
                    REG_OPTION_NON_VOLATILE ,  // special options flag 
                    access,             // desired security access 
                    NULL,               // address of key security structure 
                    &m_hKey,            // address of buffer for opened handle 
                    &dwDisposition      // address of disposition value buffer 
                    ); 

    if (lResult != ERROR_SUCCESS)
    {
        m_hKey = NULL;
    }

    if (pDisposition)
        *pDisposition = dwDisposition;

    return lResult;
}

/*--------------------------------------------------------------------------------------------------------
* DWORD OpenKey(HKEY hKey, LPCTSTR lpSubKey, REGSAM access) ()
* opens the key specified. before attempting any operation on any key/value. this function
* must be called.
* hKey - hive
* lpSubKey - Path of the key in the format _T("SYSTEM\\CurrentControlSet\\Control\\Terminal Server")
* access - access desired. like REG_READ, REG_WRITE..
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::OpenKey(HKEY hKey, LPCTSTR lpSubKey, REGSAM access /*= KEY_ALL_ACCESS*/ )
{
    ASSERT(lpSubKey);
    ASSERT(*lpSubKey != '\\');

    if (m_hKey != NULL)
    {
        RegCloseKey(m_hKey);
        m_hKey = NULL;
    }
    
    LONG lResult = RegOpenKeyEx( 
        hKey,                       // handle of open key 
        lpSubKey,                   // address of name of subkey to open 
        0 ,                         // reserved 
        access,                     // security access mask 
        &m_hKey                     // address of handle of open key 
        );
    
    if (lResult != ERROR_SUCCESS)
    {
        m_hKey = NULL;
    }
    
    return lResult;
}


DWORD CRegistry::RecurseDeleteKey (LPCTSTR lpSubKey)
{
    ASSERT(lpSubKey);
    ASSERT(m_hKey);

    CRegistry reg;
    DWORD dwError = reg.OpenKey(m_hKey, lpSubKey);
    if (dwError != ERROR_SUCCESS)
        return dwError;

    
    LPTSTR lpChildKey;
    DWORD  dwSize;
    
    // we needn't/shouldn't use GetNextSubKey in here
    // as we are deleting the keys in the loop.
    while (ERROR_SUCCESS == reg.GetFirstSubKey(&lpChildKey, &dwSize))
    {
        reg.RecurseDeleteKey(lpChildKey);
    }

    return RegDeleteKey(m_hKey, lpSubKey);
    
}

/*--------------------------------------------------------------------------------------------------------
* DWORD ReadReg(LPCTSTR lpValue, LPBYTE *lppbyte, DWORD *pdw, DWORD dwDatatype)
* Reads the registry used internally.
* LPCTSTR lpValue - value to be read.
* LPBYTE *lppbyte - address of the lpbyte at which to place the output buffer.
* DWORD  *pdw  - address of dword in which size of the buffer (in bytes) is returned.
* dword datatype - datatype you are expecting.
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::ReadReg(LPCTSTR lpValue, LPBYTE *lppbyte, DWORD *pdw, DWORD dwDatatype)
{
    ASSERT(lpValue);
    ASSERT(lppbyte);
    ASSERT(pdw);
    ASSERT(m_hKey != NULL);
    *pdw = 0;
    
    DWORD dwType;
    DWORD lResult = RegQueryValueEx( 
        m_hKey,             // handle of key to query 
        lpValue,            // address of name of value to query 
        0,                  // reserved 
        &dwType,            // address of buffer for value type 
        0,                  // address of data buffer 
        pdw                 // address of data buffer size 
        ); 
    
    if (lResult == ERROR_SUCCESS)
    {
        ASSERT(dwType == dwDatatype || dwType == REG_EXPAND_SZ);
    
        if (0 == Allocate(*pdw))
            return ERROR_OUTOFMEMORY;

        lResult = RegQueryValueEx( 
            m_hKey,                 // handle of key to query 
            lpValue,                // address of name of value to query 
            0,                      // reserved 
            &dwType,                // address of buffer for value type 
            m_pMemBlock,            // address of data buffer 
            pdw                     // address of data buffer size 
            ); 
    
        ASSERT (ERROR_MORE_DATA != lResult);
    
        if (lResult == ERROR_SUCCESS)
            *lppbyte = m_pMemBlock;
    }
    
    return lResult;
}

/*--------------------------------------------------------------------------------------------------------
* DWORD ReadRegString(LPCTSTR lpValue, LPTSTR *lppStr, DWORD *pdw)
* Reads A string (REG_SZ) from the registry
* LPCTSTR lpValue value to be read.
* LPTSTR *lppStr - address of LPTSTR in which resultant buffer is returned. caller must copy 
* the buffer to immediately. caller must not use this buffer except for copying it. 
* caller must not write to this buffer.
* DWORD  *pdw  - address of dword in which size of the buffer (in bytes) is returned.
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::ReadRegString(LPCTSTR lpValue, LPTSTR *lppStr, DWORD *pdw)
{
    return ReadReg(lpValue, (LPBYTE *)lppStr, pdw, REG_SZ);
}

/*--------------------------------------------------------------------------------------------------------
* DWORD ReadRegDWord(LPCTSTR lpValue, DWORD *pdw)
* Reads A string (REG_SZ) from the registry
* LPCTSTR lpValue value to be read.
* DWORD  *pdw  - address of dword in which the read dword returned.
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::ReadRegDWord(LPCTSTR lpValue, DWORD *pdw)
{
    ASSERT(pdw);
    
    DWORD dwSize;
    LPBYTE pByte;
    DWORD dwReturn = ReadReg(lpValue, &pByte, &dwSize, REG_DWORD);
    ASSERT(dwSize == sizeof(DWORD));
    *pdw = * LPDWORD(pByte);
    return dwReturn;
}

/*--------------------------------------------------------------------------------------------------------
* DWORD ReadRegMultiString(LPCTSTR lpValue, LPTSTR *lppStr, DWORD *pdw)
* Reads A string (REG_MULTI_SZ) from the registry
* LPCTSTR lpValue value to be read.
* LPTSTR *lppStr - address of LPTSTR in which resultant buffer is returned. caller must copy 
* the buffer to immediately. caller must not use this buffer except for copying it. 
* caller must not write to this buffer.
* DWORD  *pdw  - address of dword in which size of the buffer (in bytes) is returned.
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::ReadRegMultiString(LPCTSTR lpValue, LPTSTR *lppStr, DWORD *pdw)
{
    return ReadReg(lpValue, (LPBYTE *)lppStr, pdw, REG_MULTI_SZ);
}

/*--------------------------------------------------------------------------------------------------------
* DWORD ReadRegBinary(LPCTSTR lpValue, LPBYTE *lppByte, DWORD *pdw)
* Reads A string (REG_MULTI_SZ) from the registry
* LPCTSTR lpValue value to be read.
* LPBYTE *lppByte - address of LPBYTE in which resultant buffer is returned. caller must copy 
* the buffer to immediately. caller must not use this buffer except for copying it. 
* caller must not write to this buffer.
* DWORD  *pdw  - address of dword in which size of the buffer (in bytes) is returned.
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::ReadRegBinary(LPCTSTR lpValue, LPBYTE *lppByte, DWORD *pdw)
{
    return ReadReg(lpValue, lppByte, pdw, REG_BINARY);
}

/*--------------------------------------------------------------------------------------------------------
* DWORD GetFirstSubKey(LPTSTR *lppStr, DWORD *pdw)
* Reads a first subkey for the key
* LPTSTR *lppStr - address of LPTSTR in which resultant buffer is returned. caller must copy 
* the buffer to immediately. caller must not use this buffer except for copying it. 
* caller must not write to this buffer.
* used to enumerate the registry.
* DWORD  *pdw  - address of dword in which size of the buffer (in bytes) is returned.
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::GetFirstSubKey(LPTSTR *lppStr, DWORD *pdw)
{
    ASSERT(lppStr);
    ASSERT(pdw);
    m_iEnumIndex = 0;
    
    return GetNextSubKey(lppStr, pdw);
}

/*--------------------------------------------------------------------------------------------------------
* DWORD GetNextSubKey(LPTSTR *lppStr, DWORD *pdw
* Reads the next subkey for the key
* LPTSTR *lppStr - address of LPTSTR in which resultant buffer is returned. caller must copy 
* the buffer to immediately. caller must not use this buffer except for copying it. 
* caller must not write to this buffer.
* used to enumerate the registry.
* DWORD  *pdw  - address of dword in which size of the buffer (in bytes) is returned.
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::GetNextSubKey(LPTSTR *lppStr, DWORD *pdw)
{
    ASSERT(lppStr);
    ASSERT(pdw);
    ASSERT(m_hKey != NULL);
    ASSERT(m_iEnumIndex >= 0); // must call GetFirstSubKey first.
    
    //FILETIME unused;
    
    *pdw = 256;
    if (0 == Allocate(*pdw))
        return ERROR_NOT_ENOUGH_MEMORY;

    LONG lResult = RegEnumKeyEx( 
        m_hKey,                     // handle of key to enumerate 
        m_iEnumIndex,               // index of subkey to enumerate 
        (LPTSTR)m_pMemBlock,        // address of buffer for subkey name 
        pdw,                        // address for size of subkey buffer 
        0,                          // reserved 
        NULL,                       // address of buffer for class string 
        NULL,                       // address for size of class buffer 
        NULL                        // address for time key last written to 
        ); 
    
    (*pdw)++;    // since null is not included in the size.
    if (ERROR_NO_MORE_ITEMS == lResult)
        return lResult;
    
    m_iEnumIndex++;
    
    if (lResult == ERROR_SUCCESS)
        *lppStr = (LPTSTR)m_pMemBlock;
    
    return lResult;
}

/*--------------------------------------------------------------------------------------------------------
* DWORD GetFirstValue(LPTSTR *lppStr, DWORD *pdw, DWORD *pDataType)
* Reads a first value for the key
* LPTSTR *lppStr - address of LPTSTR in which resultant buffer is returned. caller must copy 
* the buffer to immediately. caller must not use this buffer except for copying it. 
* caller must not write to this buffer.
* used to enumerate the registry.
* DWORD  *pdw  - address of dword in which size of the buffer (in bytes) is returned.
* DWORD *pDataType - datatype of the value is returned in this one.
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::GetFirstValue(LPTSTR *lppStr, DWORD *pdw, DWORD *pDataType)
{
    ASSERT(lppStr);
    ASSERT(pdw);
    ASSERT(pDataType);
    
    m_iEnumValueIndex = 0;
    return GetNextValue(lppStr, pdw, pDataType);
}

/*--------------------------------------------------------------------------------------------------------
* DWORD GetNextValue(LPTSTR *lppStr, DWORD *pdw, DWORD *pDataType)
* Reads a next value for the key
* LPTSTR *lppStr - address of LPTSTR in which resultant buffer is returned. caller must copy 
* the buffer to immediately. caller must not use this buffer except for copying it. 
* caller must not write to this buffer.
* used to enumerate the registry.
* DWORD  *pdw  - address of dword in which size of the buffer (in bytes) is returned.
* DWORD *pDataType - datatype of the value is returned in this one.
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::GetNextValue(LPTSTR *lppStr, DWORD *pdw, DWORD *pDataType)
{
    ASSERT(lppStr);
    ASSERT(pdw);
    ASSERT(pDataType);
    ASSERT(m_hKey != NULL);
    ASSERT(m_iEnumValueIndex >= 0); // must call GetFirstSubKey first.
    
    *pdw = 256;
    if (0 == Allocate(*pdw))
        return ERROR_NOT_ENOUGH_MEMORY;
    
    LONG lResult = RegEnumValue( 
        m_hKey,                     // handle of key to query 
        m_iEnumValueIndex,          // index of value to query 
        (LPTSTR)m_pMemBlock,        // address of buffer for value string 
        pdw,                        // address for size of value buffer 
        0,                          // reserved 
        pDataType,                  // address of buffer for type code 
        NULL,                       // address of buffer for value data    maks_todo : use this
        NULL                        // address for size of data buffer 
        ); 
    
    (*pdw)++;    // since null is not included in the size.
    
    if (ERROR_NO_MORE_ITEMS == lResult)
        return lResult;
    
    
    m_iEnumValueIndex++;
    if (lResult == ERROR_SUCCESS)
        *lppStr = (LPTSTR)m_pMemBlock;
    
    return lResult;
}

/*--------------------------------------------------------------------------------------------------------
* DWORD WriteRegString(LPCTSTR lpValueName, LPCTSTR lpStr)
* writes REG_SZ value into the registry 
* LPCTSTR lpValueName - value name to be written to 
* LPCTSTR lpStr - data to be written 
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::WriteRegString(LPCTSTR lpValueName, LPCTSTR lpStr)
{
    ASSERT(m_hKey != NULL);     // call setkey before calling this function.
    ASSERT(lpValueName);
    ASSERT(lpStr);

    DWORD dwSize = (_tcslen(lpStr) + 1) * sizeof(TCHAR) / sizeof(BYTE);
    return RegSetValueEx( 
        m_hKey,                 // handle of key to set value for 
        lpValueName,            // address of value to set 
        0,                      // Reserved 
        REG_SZ,                 // flag for value type 
        (LPBYTE)lpStr,          // address of value data 
        dwSize                  // size of value data 
        ); 
}

/*--------------------------------------------------------------------------------------------------------
* DWORD WriteRegMultiString(LPCTSTR lpValueName, LPCTSTR lpStr, DWORD dwSize)
* writes REG_MULTI_SZ value into the registry 
* LPCTSTR lpValueName - value name to be written to 
* LPCTSTR lpStr - data to be written 
* DWORD   dwSize - size of data.
* RETURNS error code.
* -------------------------------------------------------------------------------------------------------*/
DWORD CRegistry::WriteRegMultiString(LPCTSTR lpValueName, LPCTSTR lpStr, DWORD dwSize)
{
    ASSERT(m_hKey != NULL);     // call setkey before calling this function.
    ASSERT(lpValueName);
    ASSERT(lpStr);

#ifdef DBG
    
    // lets make sure that the given size is right.
    LPCTSTR lpTemp = lpStr;
    DWORD rightsize = 0;
    while (_tcslen(lpTemp) > 0)
    {
        rightsize  += _tcslen(lpTemp) + 1;
        lpTemp += _tcslen(lpTemp) + 1;
    }

    ASSERT(*lpTemp == 0);           // final NULL.
    rightsize++;                    // account for final terminating null

    rightsize *= sizeof(TCHAR) / sizeof(BYTE); // size must be in bytes.

    ASSERT(dwSize == rightsize);
    
#endif

    return RegSetValueEx(
        m_hKey,                 // handle of key to set value for 
        lpValueName,            // address of value to set 
        0,                      // Reserved 
        REG_MULTI_SZ,           // flag for value type 
        (LPBYTE)lpStr,          // address of value data 
        dwSize                  // size of value data 
        ); 
}

// EOF