utility.cpp

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// Get needed system and custom include files
#include "Utility.h"
#include <stdlib.h>
#include <time.h>
#include <sys/types.h>
#include <sys/timeb.h>
#include <strstream>


// Generic error reporting function
// Display error text and HRESULT
void ReportError(const std::string& strErrorText, HRESULT hResult)
{
   #ifdef NO_CONSOLE
      std::strstream strbuff;
      strbuff << "Error: \"" << strErrorText << "\"\n";
      strbuff << "HRESULT: 0x" << std::hex << (ULONG) hResult << std::dec << std::ends;
      MessageBox(NULL, strbuff.str(), "Error", MB_OK | MB_ICONWARNING);
   #else
      std::cout << "Error: \"" << strErrorText << "\"\n";
      std::cout << "HRESULT: 0x" << std::hex << (ULONG) hResult << std::dec << std::endl;
   #endif
}


// Convert a ULONG to a string or CString object
UTILSTR ULongToStr(const ULONG ulNumber)
{
   CHAR chBuffer[33];
   _ultoa(ulNumber, chBuffer, 10);
   return UTILSTR(chBuffer);
}


//
// The following two methods were written by Microsoft technical support
// staff. A detailed writeup of these functions can be found in the
// Microsoft OLE Knowledge Base, article Q138813.
//
//


/*
 * AnsiToUnicode converts the ANSI string pszA to a Unicode string
 * and returns the Unicode string through ppszW. Space for the
 * the converted string is allocated by AnsiToUnicode.
 */
HRESULT __fastcall AnsiToUnicode(LPCSTR pszA, LPOLESTR* ppszW)
{
   ULONG cCharacters;
   DWORD dwError;

   // If input is null then just return the same.
   if (NULL == pszA)
   {
      *ppszW = NULL;
      return NOERROR;
   }

   // Determine number of wide characters to be allocated for the
   // Unicode string.
   cCharacters =  strlen(pszA)+1;

   // Use of the OLE allocator is required if the resultant Unicode
   // string will be passed to another COM component and if that
   // component will free it. Otherwise you can use your own allocator.
   *ppszW = (LPOLESTR) CoTaskMemAlloc(cCharacters*2);
   if (NULL == *ppszW)
      return E_OUTOFMEMORY;

   // Covert to Unicode.
   if (0 == MultiByteToWideChar(CP_ACP, 0, pszA, cCharacters,
                                *ppszW, cCharacters))
   {
      dwError = GetLastError();
      CoTaskMemFree(*ppszW);
      *ppszW = NULL;
      return HRESULT_FROM_WIN32(dwError);
   }

   return NOERROR;
}


/*
 * UnicodeToAnsi converts the Unicode string pszW to an ANSI string
 * and returns the ANSI string through ppszA. Space for the
 * the converted string is allocated by UnicodeToAnsi.
 */
HRESULT __fastcall UnicodeToAnsi(LPCOLESTR pszW, LPSTR* ppszA)
{
   ULONG cbAnsi, cCharacters;
   DWORD dwError;

   // If input is null then just return the same.
   if (pszW == NULL)
   {
       *ppszA = NULL;
       return NOERROR;
   }

   cCharacters = wcslen(pszW)+1;
   // Determine number of bytes to be allocated for ANSI string. An
   // ANSI string can have at most 2 bytes per character (for Double
   // Byte Character Strings.)
   cbAnsi = cCharacters*2;

   // Use of the OLE allocator is not required because the resultant
   // ANSI string will never be passed to another COM component. You
   // can use your own allocator.
   *ppszA = (LPSTR) CoTaskMemAlloc(cbAnsi);
   if (NULL == *ppszA)
      return E_OUTOFMEMORY;

   // Convert to ANSI.
   if (0 == WideCharToMultiByte(CP_ACP, 0, pszW, cCharacters, *ppszA,
                                cbAnsi, NULL, NULL))
   {
      dwError = GetLastError();
      CoTaskMemFree(*ppszA);
      *ppszA = NULL;
      return HRESULT_FROM_WIN32(dwError);
   }

   return NOERROR;
}
 

// Function to seed the random number generator based on the system time
void SeedRandomGenerator()
{
   struct _timeb timebuffer;
   _ftime(&timebuffer);
   srand(timebuffer.millitm);
}