registrytree.cpp

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    SetError(_T("Cannot delete subkeys(s) of key %s.\nSubkey enumeration failed.\nError %d (%s)\n"),
             rKey.GetKeyName(),nError,GetErrorDescription(nError));
    return FALSE;
  }

  if (!blnKeyDeleted)
    SetError(_T("The key %s has no subkeys that match %s pattern.\n"),rKey.GetKeyName(),pszKeyPattern);

  return blnKeyDeleted;
}

const TCHAR * CRegistryTree::GetErrorDescription(LONG nError)
{
  switch(nError)
  {
  case ERROR_ACCESS_DENIED:
    return _T("Access denied");
  case ERROR_FILE_NOT_FOUND:
    return _T("The system cannot find the key specified");
  case ERROR_INTERNAL_ERROR:
    return _T("Internal error");
  case ERROR_OUTOFMEMORY:
    return _T("Out of memory");
  default:
    return _T("Unknown error");
  }
}

void CRegistryTree::SetError(LONG nError)
{
  SetError(_T("Error %u (%s)"),nError,GetErrorDescription(nError));
}

void CRegistryTree::SetError(const TCHAR *pszFormat, ...)
{
  va_list args;
  va_start(args,pszFormat);
  if (_vsntprintf(m_ErrorMsg,ERROR_MSG_BUFFER_SIZE,pszFormat,args) < 0)
    m_ErrorMsg[ERROR_MSG_BUFFER_SIZE] = 0;
  va_end(args);
}

void CRegistryTree::SetInternalError()
{
  SetError(_T("Internal Error"));
}

void CRegistryTree::AddErrorDescription(const TCHAR *pszFormat, ...)
{
  size_t size = _tcslen(m_ErrorMsg);
  if (size < ERROR_MSG_BUFFER_SIZE)
  {
    TCHAR *pszAdd = m_ErrorMsg+size;
    va_list args;
    va_start(args,pszFormat);
    size = ERROR_MSG_BUFFER_SIZE-size;
    if (_vsntprintf(pszAdd,size,pszFormat,args) < 0)
      m_ErrorMsg[size] = 0;
    va_end(args);
  }
}

void CRegistryTree::SetErrorCommandNAOnRoot(const TCHAR *pszCommand)
{
  ASSERT(pszCommand);
  if (pszCommand)
    SetError(_T("%s") COMMAND_NA_ON_ROOT,pszCommand);
  else
    SetInternalError();
}

BOOL CRegistryTree::InternalChangeCurrentKey(const TCHAR *pszSubkeyName, REGSAM DesiredAccess)
{
  size_t size = _tcslen(pszSubkeyName);
  TCHAR *pszSubkeyNameBuffer = new TCHAR[size+3];
  if (!pszSubkeyNameBuffer)
  {
    SetError(_T("Cannot open key : %s%s\nError %d (%s)\n"),
             GetCurrentPath(),pszSubkeyName,ERROR_OUTOFMEMORY,GetErrorDescription(ERROR_OUTOFMEMORY));
  }

  _tcscpy(pszSubkeyNameBuffer,pszSubkeyName);
  if (size && (pszSubkeyName[0] == _T('\"')) && (pszSubkeyName[size-1] == _T('\"')))
  {
    pszSubkeyNameBuffer[size-1] = 0;
    pszSubkeyName = pszSubkeyNameBuffer+1;
  }
  
  if (_tcscmp(pszSubkeyName,_T(".")) == 0)
  {
    delete pszSubkeyNameBuffer;
    return TRUE;
  }

  if (_tcscmp(pszSubkeyName,_T("..")) == 0)
  {
    // Up level abstraction
    if (m_pCurrentKey->m_Key.IsRoot())
    {
      // We are on root
      ASSERT(m_pCurrentKey->m_pUp == NULL);
      SetError(_T("Cannot open key. The root is not child.\n"));
      delete pszSubkeyNameBuffer;
      return FALSE;
    }
      
    ASSERT(m_pCurrentKey->m_pUp);
    if (!m_pCurrentKey->m_pUp)
    {
      SetInternalError();
      delete pszSubkeyNameBuffer;
      return FALSE;
    }
    CNode *pNode = m_pCurrentKey;
    m_pCurrentKey = m_pCurrentKey->m_pUp;
    delete pNode;
    delete pszSubkeyNameBuffer;
    return TRUE;
  }

  CNode *pNewKey = new CNode;
  if (!pNewKey)
  {
    SetError(_T("Cannot open key : %s%s\nError %d (%s)\n"),
             GetCurrentPath(),pszSubkeyName,ERROR_OUTOFMEMORY,GetErrorDescription(ERROR_OUTOFMEMORY));
    delete pszSubkeyNameBuffer;
    return FALSE;
  }

  if (!InternalGetSubkey(pszSubkeyName,DesiredAccess,pNewKey->m_Key))
  {
    delete pNewKey;
    delete pszSubkeyNameBuffer;
    return FALSE;
  }
  pNewKey->m_pUp = m_pCurrentKey;
  m_pCurrentKey = pNewKey;
  
  delete pszSubkeyNameBuffer;
  return TRUE;
}

BOOL CRegistryTree::InternalGetSubkey(const TCHAR *pszSubkeyName, REGSAM DesiredAccess, CRegistryKey& rKey)
{
  LONG nError;
  HKEY hNewKey = NULL;
  TCHAR *pszSubkeyNameCaseUpdated = NULL;

  nError = m_pCurrentKey->m_Key.OpenSubkey(DesiredAccess,pszSubkeyName,hNewKey);

  if (nError != ERROR_SUCCESS)
  {
		SetError(_T("Cannot open key : %s%s\nError %u (%s)\n"),
             GetCurrentPath(),pszSubkeyName,nError,GetErrorDescription(nError));

    return FALSE;
  }

  // enum subkeys to find the subkey and get its name in stored case.
  DWORD dwMaxSubkeyNameLength;
	nError = m_pCurrentKey->m_Key.GetSubkeyNameMaxLength(dwMaxSubkeyNameLength);
  if (nError != ERROR_SUCCESS)
    goto SkipCaseUpdate;
  
  pszSubkeyNameCaseUpdated = new TCHAR [dwMaxSubkeyNameLength];
  m_pCurrentKey->m_Key.InitSubkeyEnumeration(pszSubkeyNameCaseUpdated, dwMaxSubkeyNameLength);
  while ((nError = m_pCurrentKey->m_Key.GetNextSubkeyName()) == ERROR_SUCCESS)
    if (_tcsicmp(pszSubkeyNameCaseUpdated, pszSubkeyName) == 0)
      break;

  if (nError != ERROR_SUCCESS)
  {
    delete pszSubkeyNameCaseUpdated;
    pszSubkeyNameCaseUpdated = NULL;
  }

SkipCaseUpdate:

  HRESULT hr;
  ASSERT(hNewKey);
  if (pszSubkeyNameCaseUpdated)
  {
    hr = rKey.Init(hNewKey,GetCurrentPath(),pszSubkeyNameCaseUpdated,DesiredAccess);
    if (FAILED(hr))
    {
      if (hr == (HRESULT)E_OUTOFMEMORY)
        SetError(_T("Cannot open key : %s%s\nError %d (%s)\n"),
                 GetCurrentPath(),pszSubkeyName,ERROR_OUTOFMEMORY,GetErrorDescription(ERROR_OUTOFMEMORY));
      else
        SetError(_T("Cannot open key : %s%s\nUnknown error\n"), GetCurrentPath(), pszSubkeyName);

      goto Abort;
    }
    
    delete pszSubkeyNameCaseUpdated;
  }
  else
  {
    hr = rKey.Init(hNewKey,GetCurrentPath(),pszSubkeyName,DesiredAccess);
    if (FAILED(hr))
    {
      if (hr == (HRESULT)E_OUTOFMEMORY)
        SetError(_T("Cannot open key : %s%s\nError %d (%s)\n"),
                 GetCurrentPath(),pszSubkeyName,ERROR_OUTOFMEMORY,GetErrorDescription(ERROR_OUTOFMEMORY));
      else
        SetError(_T("Cannot open key : %s%s\nUnknown error \n"),
                 GetCurrentPath(),
                 pszSubkeyName);
      
      goto Abort;
    }
  }
  
  return TRUE;
Abort:
  if (pszSubkeyNameCaseUpdated)
    delete pszSubkeyNameCaseUpdated;

  if (hNewKey)
  {
    LONG nError = RegCloseKey(hNewKey);
    ASSERT(nError == ERROR_SUCCESS);
  }
  
  return FALSE;
}

BOOL CRegistryTree::GetKey(const TCHAR *pszRelativePath, REGSAM DesiredAccess, CRegistryKey& rKey)
{
  CRegistryTree Tree(*this);

  if (!Tree.ChangeCurrentKey(pszRelativePath))
  {
    SetError(Tree.GetLastErrorDescription());
    return FALSE;
  }

  if (Tree.m_pCurrentKey->m_Key.IsRoot())
  {
    HRESULT hr = rKey.InitRoot(m_pszMachineName);
    if (FAILED(hr))
    {
      if (hr == (HRESULT)E_OUTOFMEMORY)
        SetError(_T("\nError %d (%s)\n"),
                 ERROR_OUTOFMEMORY,GetErrorDescription(ERROR_OUTOFMEMORY));
      else
        SetInternalError();
      return FALSE;
    }
    
    return TRUE;
  }

  // open key with desired access
  
  // may be call to DuplicateHandle() is better.
  // registry key handles returned by the RegConnectRegistry function cannot be used in a call to DuplicateHandle.

  // Get short key name now...
  const TCHAR *pszKeyName = Tree.m_pCurrentKey->m_Key.GetKeyName();
  if (pszKeyName == NULL)
  {
    SetInternalError();
    return FALSE;
  }
  
  size_t size = _tcslen(pszKeyName);
  ASSERT(size);
  if (!size)
  {
    SetInternalError();
    return FALSE;
  }
  
  const TCHAR *pszShortKeyName_ = pszKeyName + size-1;
  pszShortKeyName_--; // skip ending backslash
  size = 0;
  while (pszShortKeyName_ >= pszKeyName)
  {
    if (*pszShortKeyName_ == _T('\\'))
      break;
    pszShortKeyName_--;
    size++;
  }
  
  if (!size || (*pszShortKeyName_ != _T('\\')))
  {
    ASSERT(FALSE);
    SetInternalError();
    return FALSE;
  }

  TCHAR *pszShortKeyName = new TCHAR [size+1];
  if (!pszShortKeyName)
  {
    SetError(ERROR_OUTOFMEMORY);
    return FALSE;
  }

  memcpy(pszShortKeyName,pszShortKeyName_+1,size*sizeof(TCHAR));
  pszShortKeyName[size] = 0;

  // change to parent key
	if (!Tree.InternalChangeCurrentKey(_T(".."),READ_CONTROL))
  {
    ASSERT(FALSE);
    SetInternalError();
    return FALSE;
  }
  
  // change back to target key
	if (!Tree.InternalGetSubkey(pszShortKeyName,DesiredAccess,rKey))
  {
    SetError(Tree.GetLastErrorDescription());
    return FALSE;
  }

  return TRUE;
}