Windows-Server-2003/inetcore/setup/active/ie4uinit/reg.cpp

135 lines
3.8 KiB
C++

#include "priv.h"
#include "advpub.h"
#include "sdsutils.h"
#include "utils.h"
#ifndef ARRAYSIZE
#define ARRAYSIZE(a) (sizeof(a)/sizeof(a[0]))
#endif
/*----------------------------------------------------------
Purpose: Behaves just like RegQueryValueEx, except if the
data type is REG_EXPAND_SZ, then this goes ahead
and expands out the string. *pdwType will always
be massaged to REG_SZ if this happens.
Returns:
Cond: --
*/
DWORD
SDSQueryValueExA(
IN HKEY hkey,
IN LPCSTR pszValue,
IN LPDWORD lpReserved,
OUT LPDWORD pdwType,
OUT LPVOID pvData,
IN OUT LPDWORD pcbData)
{
DWORD dwRet;
DWORD cbSize;
DWORD dwType;
LPSTR lpsz;
if (pvData)
{
// Trying to get back data
cbSize = *pcbData; // Size of output buffer
dwRet = RegQueryValueExA(hkey, pszValue, lpReserved, &dwType,
(LPBYTE)pvData, &cbSize);
// Normally, we'd be done with this. But do some extra work
// if this is an expandable string (something that has system
// variables in it), or if we need to pad the buffer.
if (NO_ERROR == dwRet)
{
// Note: on Win95, RegSetValueEx will always write the
// full string out, including the null terminator. On NT,
// it won't unless the write length was specified.
// Hence, we have the following check.
// Pad the buffer, in case the string didn't have a null
// terminator when it was stored?
if (REG_SZ == dwType)
{
// Yes
if (cbSize < *pcbData)
{
LPSTR lpszData = (LPSTR)pvData;
lpszData[cbSize] = '\0';
}
}
// Expand the string?
else if (REG_EXPAND_SZ == dwType)
{
// Yes
// Use a temporary buffer to expand
lpsz = (LPSTR)LocalAlloc(LPTR, *pcbData);
if ( !lpsz )
return ERROR_OUTOFMEMORY;
cbSize = ExpandEnvironmentStringsA((LPSTR)pvData, lpsz, *pcbData);
// BUGBUG:: NT screws up the cbSize returned...
if (cbSize > 0)
cbSize = lstrlen(lpsz) + 1;
if (cbSize > 0 && cbSize <= *pcbData)
lstrcpynA((LPSTR)pvData, lpsz, *pcbData);
else
dwRet = GetLastError();
LocalFree(lpsz);
// Massage dwType so that callers always see REG_SZ
dwType = REG_SZ;
}
}
}
else
{
// Trying to find out how big of a buffer to use
cbSize = 0;
dwRet = RegQueryValueExA(hkey, pszValue, lpReserved, &dwType,
NULL, &cbSize);
if (NO_ERROR == dwRet && REG_EXPAND_SZ == dwType)
{
CHAR szBuff[1];
// Find out the length of the expanded string
//
lpsz = (LPSTR)LocalAlloc(LPTR, cbSize);
if (!lpsz)
return ERROR_OUTOFMEMORY;
dwRet = RegQueryValueExA(hkey, pszValue, lpReserved, NULL,
(LPBYTE)lpsz, &cbSize);
if (NO_ERROR == dwRet)
{
cbSize = ExpandEnvironmentStringsA(lpsz, szBuff, ARRAYSIZE(szBuff));
// BUGBUG:: NT screws up the cbSize returned...
if (cbSize > 0)
cbSize = lstrlen(lpsz) + 1;
}
LocalFree(lpsz);
// Massage dwType so that callers always see REG_SZ
dwType = REG_SZ;
}
}
if (pdwType)
*pdwType = dwType;
if (pcbData)
*pcbData = cbSize;
return dwRet;
}