//
// Copyright (c) Microsoft Corporation.  All rights reserved.
//
//
// Use of this source code is subject to the terms of the Microsoft shared
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// this source code. If you did not accept the terms of the license agreement,
// you are not authorized to use this source code. For the terms of the license,
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/***************************************************************************/
/**                  Microsoft Windows                                    **/
/***************************************************************************/


/****************************************************************************

regentry.h

Oct. 95     LenS

Wrapper for registry access

Construct a RegEntry object by specifying the subkey (under
HKEY_CURRENT_USER by default, but can be overridden.)

All member functions (except the destructor) set an internal
error state which can be retrieved with GetError().
Zero indicates no error.

RegEntry works only with strings and DWORDS which are both set
using the overloaded function SetValue()

    SetValue("valuename", "string");
    SetValue("valuename", 42);
    
Values are retrieved with GetString() and GetNumber().  
GetNumber() allows you to specificy a default if the valuename doesn't
exist.
GetString() returns a pointer to a string internal to RegEntry that is 
invalidated when another function is called on the same RegEntry object
(e.g. its destructor) so, if you want to use the string beyond this
time, then you must copy it out of the RegEntry object first.

DeleteValue() removes the valuename and value pair.

Registry flushes are automatic when RegEntry is destroys or moves to
another key.

****************************************************************************/

#ifndef REGENTRY_INC
#define REGENTRY_INC

class RegEntry
{
    public:
        RegEntry(   LPCTSTR pszSubKey,
                    HKEY hkey = HKEY_LOCAL_MACHINE,
                    BOOL fCreate = TRUE,
                    REGSAM samDesired = 0
                    );
        ~RegEntry();

        long    GetError()  { return m_error;}
        BOOL    Success() { return m_error == ERROR_SUCCESS;}
        VOID    ClearError() {m_error = ERROR_SUCCESS;}
        long    SetValue(LPCTSTR pszValueName, LPCTSTR string);
        long    SetValue(LPCTSTR pszValueName, unsigned long dwNumber);
        long    SetValue(LPCTSTR pszValue, void* pData, DWORD cbLength);
        LPTSTR  GetString(LPCTSTR pszValueName);
        DWORD   GetBinary(LPCTSTR pszValueName, void** ppvData);
        long    GetNumber(LPCTSTR pszValueName, long dwDefault = 0);
        ULONG   GetNumberIniStyle(LPCTSTR pszValueName, ULONG dwDefault = 0);
        long    DeleteValue(LPCTSTR pszValueName);
        long    FlushKey();
        VOID    MoveToSubKey(LPCTSTR pszSubKeyName);
        HKEY    GetKey()    { return m_hkey; }
        DWORD   GetDisposition() { return m_dwDisposition; }
        VOID    DeleteKey() {ChangeKey(NULL); m_fhkeyValid = NULL;}

    private:
        VOID    ChangeKey(HKEY hNewKey);
        VOID    UpdateWrittenStatus();
        VOID    ResizeValueBuffer(DWORD length);

        HKEY    m_hkey;
        DWORD   m_dwDisposition;
        long    m_error;
        BOOL    m_fhkeyValid;
        LPBYTE  m_pbValueBuffer;
        DWORD   m_cbValueBuffer;
        BOOL    m_fValuesWritten;
        TCHAR   m_szNULL;
};


inline long 
RegEntry::FlushKey()
{
    if (m_fhkeyValid) {
        m_error = RegFlushKey(m_hkey);
    }
    return m_error;
}


class RegEnumValues
{
    public:
        RegEnumValues(RegEntry *pRegEntry);
        ~RegEnumValues();
        long    Next();
        LPTSTR  GetName()       {return m_pchName;}
        DWORD   GetType()       {return m_dwType;}
        LPBYTE  GetData()       {return m_pbValue;}
        DWORD   GetDataLength() {return m_dwDataLength;}
        DWORD   GetCount()      {return m_cEntries;}
        long    GetError()  { return m_error;}
        BOOL    Success() { return m_error == ERROR_SUCCESS;}

    private:
        RegEntry * m_pRegEntry;
        DWORD   m_iEnum;
        DWORD   m_cEntries;
        LPTSTR  m_pchName;
        LPBYTE  m_pbValue;
        DWORD   m_dwType;
        DWORD   m_dwDataLength;
        DWORD   m_cMaxValueName;
        DWORD   m_cMaxData;
        LONG    m_error;
};

class RegEnumSubKeys
{
    public:
        RegEnumSubKeys(RegEntry *pRegEntry);
        ~RegEnumSubKeys();
        long    Next();
        LPTSTR  GetName()       {return m_pchName;}
        DWORD   GetCount()      {return m_cEntries;}
        DWORD   GetMaxSubKeyLength()    {return m_cMaxKeyName;}
        long    GetError()  { return m_error;}
        BOOL    Success() { return m_error == ERROR_SUCCESS;}

    protected:
        RegEntry * m_pRegEntry;
        DWORD   m_iEnum;
        DWORD   m_cEntries;
        LPTSTR  m_pchName;
        DWORD   m_cMaxKeyName;
        LONG    m_error;
};

#endif // REGENTRY_INC
