Subversion Repositories Games.Chess Giants

// util.cpp

#include "common.h"

// internal typedefs

typedef struct wsaerror_s

{

   int number;

   const wchar_t *description;

} wsaerror_t;

const wchar_t *GetDirectoryPath (const wchar_t *pathname, wchar_t *path)

{

   // this function builds a directory path out of a full file pathname

   int char_index;

   int length;

   length = (int) wcslen (pathname); // get length of pathname first

   if (length > MAX_PATH - 1)

      length = MAX_PATH - 1; // bound it to MAX_PATH characters max

   for (char_index = 0; char_index < length; char_index++)

   {

      path[char_index] = pathname[char_index]; // now copy pathname in the destination string

      if (pathname[char_index] == 0)

         break; // don't copy beyond the end of source

   }

   path[length] = 0; // terminate the string

   // now scan the destination string starting from the end until a field separator is found

   while ((length > 0) && !((path[length] == '\\') || (path[length] == '/')) && (path[length] != ':'))

      length--; // go back one character after the other as long as it's not the case

   // given the type of field separator we stopped on, keep it or not

   if (path[length] == ':')

      length++; // if it's a disk letter separator, keep it

   path[length] = 0; // terminate the string at this position

   return (path); // and return a pointer to it

}

void CenterWindow (HWND hWnd, HWND hParentWnd)

{

   // this function centers the specified window on the specified parent.

   RECT rRect;

   RECT rParentRect;

   int width;

   int height;

   int parent_width;

   int parent_height;

   int x;

   int y;

   // get the current rectangle of the current window

   GetWindowRect (hWnd, &rRect);

   width = rRect.right - rRect.left;

   height = rRect.bottom - rRect.top;

   // does this window have a parent AND it is NOT the desktop ?

   if (IsWindow (hParentWnd) && (hParentWnd != GetDesktopWindow ()))

   {

      // get the rectangle of the parent window

      GetWindowRect (hParentWnd, &rParentRect);

      parent_width = rParentRect.right - rParentRect.left;

      parent_height = rParentRect.bottom - rParentRect.top;

      // now compute the new X and Y positions so as to have the window centered in its parent

      x = rParentRect.left + parent_width / 2 - width / 2;

      y = rParentRect.top + parent_height / 2 - height / 2;

   }

   else

   {

      // else draw window in the center of the screen

      x = GetSystemMetrics (SM_CXSCREEN) / 2 - width / 2;

      y = GetSystemMetrics (SM_CYSCREEN) / 2 - height / 2;

   }

   // now ask to change the position of the window

   SetWindowPos (hWnd, NULL, x, y, 0, 0, SWP_NOSIZE | SWP_NOZORDER);

   return; // finished

}

void HintWindow (HWND hWnd)

{

   // this function makes a window blink to the foreground for one second, playing a "ding" sound

   FLASHWINFO fw;

   PlaySound (L"SystemDefault", NULL, SND_ALIAS | SND_ASYNC); // play a beep

   SetForegroundWindow (hWnd); // modal dialog windows have priority over all others

   fw.cbSize = sizeof (fw);

   fw.hwnd = hWnd;

   fw.dwFlags = FLASHW_CAPTION;

   fw.dwTimeout = 50;

   fw.uCount = 3;

   FlashWindowEx (&fw); // flash it so the user notices it

   return; // finished

}

float ProcessTime (void)

{

   // this function returns the time in seconds elapsed since the executable process started.

   // The rollover check ensures the program will continue running after clock() will have

   // overflown its integer value (it does so every 24 days or so). With this rollover check

   // we have a lifetime of more than billion years, w00t!

   // thanks to botmeister for the rollover check idea.

   static long prev_clock = 0;

   static long rollover_count = 0;

   long current_clock;

   double time_in_seconds;

   current_clock = clock (); // get system clock

   // has the clock overflown ?

   if (current_clock < prev_clock)

      rollover_count++; // omg, it has, we're running for more than 24 days!

   // now convert the time to seconds since last rollover

   time_in_seconds = (double) current_clock / CLOCKS_PER_SEC; // convert clock to seconds

   prev_clock = current_clock; // keep track of current time for future calls of this function

   // and return the time in seconds, adding the overflow differences if necessary.

   // HACK: grant the timer to start at 60 seconds to ensure all timer checks work well

   return ((float) (60.0f + time_in_seconds + (((double) LONG_MAX + 1.0) / CLOCKS_PER_SEC) * rollover_count));

}

float WrapAngle (float angle)

{

   // this function adds or substracts 360 enough times needed to angle to clamp it into the

   // [-180, 180[ bounds.

   if (angle < -180.0f)

      angle += 360.0f * abs (((int) angle - 180) / 360);

   else if (angle >= 180)

      angle -= 360.0f * abs (((int) angle + 180) / 360);

   if (angle == 180.0f)

      angle = -180.0f; // needs 2nd pass to check for floating-point rounding errors

   return (angle); // finished

}

bool SafeTerminateProcess (HANDLE hProcess, unsigned int uExitCode)

{

   // taken from Dr. Dobbs : how to terminate any process cleanly. Simple : Create a remote

   // thread in it, and make its start address point right into kernel32's ExitProcess()

   // function. This of course assumes that remote code injection is possible.

   unsigned long dwTID;

   unsigned long dwCode;

   unsigned long dwErr = 0;

   HMODULE hModule;

   HANDLE hProcessDup;

   HANDLE hRT;

   bool bSuccess = false;

   bool bDup;

   bDup = (DuplicateHandle (GetCurrentProcess (), hProcess, GetCurrentProcess (), &hProcessDup, PROCESS_ALL_ACCESS, FALSE, 0) != 0);

   // detect the special case where the process is already dead

   if (GetExitCodeProcess (bDup ? hProcessDup : hProcess, &dwCode) && (dwCode == STILL_ACTIVE))

   {

      hModule = GetModuleHandle (L"Kernel32");

      if (hModule)

      {

         hRT = CreateRemoteThread (bDup ? hProcessDup : hProcess, NULL, 0,

                                   (LPTHREAD_START_ROUTINE) GetProcAddress (hModule, "ExitProcess"),

                                   (void *) uExitCode, 0, &dwTID);

         if (hRT != NULL)

         {

            // must wait process to terminate to guarantee that it has exited

            WaitForSingleObject (bDup ? hProcessDup : hProcess, INFINITE);

            CloseHandle (hRT);

            bSuccess = true;

         }

         else

            dwErr = GetLastError ();

      }

      else

         dwErr = GetLastError ();

   }

   else

      dwErr = ERROR_PROCESS_ABORTED;

   if (bDup)

      CloseHandle (hProcessDup);

   if (!bSuccess)

      SetLastError (dwErr);

   return (bSuccess);

}

wchar_t *ReachBeginningOfCurrentLine (wchar_t *string, wchar_t *current_pos)

{

   // this function parses string backwards from current_pos until it finds either a line feed,

   // or the beginning of string, and returns the first character of the line.

   while ((current_pos > string) && (*current_pos != L'\n'))

      current_pos--; // find the previous line feed

   if (*current_pos == L'\n')

      current_pos++; // if we've found one, skip it

   return (current_pos); // and return where we are

}

wchar_t *ReachBeginningOfNextLine (wchar_t *string, wchar_t *current_pos)

{

   // this function parses string forward from current_pos until it finds either a line feed,

   // or the end of string, and returns the first character of the line (or NULL).

   current_pos = wcschr (current_pos, L'\n'); // find the next line feed

   if (current_pos != NULL)

      current_pos++; // if we've found one, skip it

   if (*current_pos == 0)

      current_pos = NULL; // if it's the end of the string, don't return anything

   return (current_pos); // and return what we've found

}

wchar_t *ReadACompleteLine (wchar_t *destination_line, int max_length, wchar_t *source_buffer)

{

   // copy a line from a given string, ONLY if it ends with a carriage return.

   // use it like:

   // while (blah = sgets (dest, sizeof (dest), blah)) != NULL)

   wchar_t *pointer;

   int char_index;

   int source_length;

   if (source_buffer[0] == 0)

   {

      destination_line[0] = 0;

      return (NULL); // if EOS return a NULL pointer

   }

   pointer = wcschr (source_buffer, L'\n'); // get to the first carriage return we can find

   // found none ?

   if (pointer == NULL)

   {

      destination_line[0] = 0;

      return (NULL); // if none return a NULL pointer

   }

   // get the number of remaining characters in source string

   source_length = wcslen (source_buffer);

   // as long as we haven't filled the destination string...

   for (char_index = 0; char_index < max_length; char_index++)

   {

      destination_line[char_index] = source_buffer[char_index]; // copy the line we found

      if ((char_index + 1 == source_length) || (source_buffer[char_index] == '\n'))

         break; // don't copy beyond the end of source string, nor beyond the end of line

   }

   if (char_index < max_length)

      destination_line[char_index] = 0; // terminate string ourselves

   else

      destination_line[max_length - 1] = 0;

   return (&pointer[1]); // and return next line's source buffer pointer

}

wchar_t *wcsgets (wchar_t *destination_line, int max_length, wchar_t *source_buffer)

{

   // copy a line from a given string. Kinda like fgets() when you're reading from a string.

   // use it like:

   // while (blah = sgets (dest, sizeof (dest), blah)) != NULL)

   wchar_t *pointer;

   int char_index;

   int source_length;

   if (source_buffer[0] == 0)

   {

      destination_line[0] = 0;

      return (NULL); // if EOS return a NULL pointer

   }

   pointer = wcschr (source_buffer, L'\n'); // get to the first carriage return we can find

   // found none ?

   if (pointer == NULL)

   {

      // if so, copy the line we found

      for (char_index = 0; char_index < max_length; char_index++)

      {

         destination_line[char_index] = source_buffer[char_index]; // copy the line we found

         if (source_buffer[char_index] == 0)

            break; // don't copy beyond the end of source

      }

      if (char_index == max_length)

         destination_line[max_length - 1] = 0; // ensure string is terminated

      return (&source_buffer[wcslen (source_buffer)]); // and return a pointer to the end of the string

   }

   else

      pointer++; // else if a carriage return was found, skip it

   // get the number of remaining characters in source string

   source_length = wcslen (source_buffer);

   // as long as we haven't filled the destination string...

   for (char_index = 0; char_index < max_length; char_index++)

   {

      destination_line[char_index] = source_buffer[char_index]; // copy the line we found

      if ((char_index + 1 == source_length) || (source_buffer[char_index] == '\n'))

         break; // don't copy beyond the end of source string, nor beyond the end of line

   }

   if (char_index < max_length)

      destination_line[char_index] = 0; // terminate string ourselves

   else

      destination_line[max_length - 1] = 0;

   return (pointer); // and return next line's source buffer pointer

}

wchar_t *wcsistr (const wchar_t *haystack, const wchar_t *needle)

{

   // windows has no wcsistr() implementation, so here is mine.

   const wchar_t *ptr_upper;

   const wchar_t *ptr_lower;

   const wchar_t *ptr_either;

   size_t needle_length;

   needle_length = wcslen (needle); // get needle length

   ptr_either = haystack; // start searching at the beginning of haystack

   for (;;) // endless loop

   {

      ptr_upper = wcschr (haystack, towupper (*needle)); // find occurence of first character (uppercase)

      ptr_lower = wcschr (haystack, towlower (*needle)); // find occurence of first character (lowercase)

      if ((ptr_upper == NULL) && (ptr_lower == NULL))

         break; // if no occurence in either case, then haystack doesn't contain needle

      else if (ptr_upper == NULL)

         ptr_either = ptr_lower; // no uppercase, check in lowercase

      else if (ptr_lower == NULL)

         ptr_either = ptr_upper; // no lowercase, check in uppercase

      else if (ptr_lower < ptr_upper)

         ptr_either = ptr_lower; // both occurences found, take the first one

      else

         ptr_either = ptr_upper; // both occurences found, take the first one

      if (_wcsnicmp (ptr_either, needle, needle_length) == 0) // now compare needle case insensitively at that position in haystack

         return ((wchar_t *) ptr_either); // if we find something, return its position

      haystack = ptr_either + 1; // else advance in haystack

   }

   return (NULL); // haystack doesn't contain needle

}

void ConvertCRLFsToSingleSpaces (wchar_t *multiline_string)

{

   // this function modifies multiline_string by removing CRs and turning LFs into single spaces

   int length;

   int char_index;

   int char_index2;

   length = wcslen (multiline_string); // get input string length

   // for each character in string that is NOT a carriage return...

   char_index2 = 0;

   for (char_index = 0; char_index < length; char_index++)

      if (multiline_string[char_index] != L'\r')

      {

         if (multiline_string[char_index] == L'\n')

            multiline_string[char_index2] = L' '; // convert newlines to spaces

         else

            multiline_string[char_index2] = multiline_string[char_index]; // else overwrite string with itself

         char_index2++; // we've written one character more

      }

   multiline_string[char_index2] = 0; // finish string

   return; // finished, string is now single-line

}

void ConvertTo7BitASCII (char *dest, size_t dest_size_in_bytes, wchar_t *source)

{

   // helper function to quickly convert a wide char string to 7-bit ASCII

   // do the conversion. Use WideCharToMultiByte() preferentially because wcstombs()

   // stops at the first non-convertible character, whereas the former doesn't.

   WideCharToMultiByte (20127, 0, source, -1, dest, dest_size_in_bytes, NULL, NULL); // 20127 is 7-bit US-ASCII code page

   return;

}

void ConvertToWideChar (wchar_t *dest, size_t dest_size_in_wchars, char *source)

{

   // helper function to quickly convert an ASCII string to wide char

   size_t converted_count;

   // do the conversion

   mbstowcs_s (&converted_count, dest, dest_size_in_wchars, source, _TRUNCATE);

   return;

}

void MinutesToWideCharString (wchar_t *dest, size_t dest_size_in_wchars, int minutes)

{

   // helper function to convert a time in minutes in a string mentioning days, hours and minutes

   int days;

   int hours;

   days = minutes / (60 * 24); // count the number of days

   minutes -= days * (60 * 24); // substract the result

   hours = minutes / 60; // count the number of hours

   minutes -= hours * 60; // substract the result

   // now choose the right display format

   if (days > 0)

      swprintf_s (dest, dest_size_in_wchars, L"%d %s %d %s %d %s", days, LOCALIZE (L"Days"), hours, LOCALIZE (L"Hours"), minutes, LOCALIZE (L"Minutes"));

   else if (hours > 0)

      swprintf_s (dest, dest_size_in_wchars, L"%d %s %d %s", hours, LOCALIZE (L"Hours"), minutes, LOCALIZE (L"Minutes"));

   else

      swprintf_s (dest, dest_size_in_wchars, L"%d %s", minutes, LOCALIZE (L"Minutes"));

   return; // finished

}

void SecondsToWideCharString (wchar_t *dest, size_t dest_size_in_wchars, int seconds)

{

   // helper function to convert a time in seconds in a string mentioning days, hours, minutes and seconds

   int days;

   int hours;

   int minutes;

   days = seconds / (60 * 60 * 24); // count the number of days

   seconds -= days * (60 * 60 * 24); // substract the result

   hours = seconds / (60 * 60); // count the number of hours

   seconds -= hours * (60 * 60); // substract the result

   minutes = seconds / 60; // count the number of minutes

   seconds -= minutes * 60; // substract the result

   // now choose the right display format

   if (days > 0)

      swprintf_s (dest, dest_size_in_wchars, L"%d %s %d %s %d %s %d %s", days, LOCALIZE (L"Days"), hours, LOCALIZE (L"Hours"), minutes, LOCALIZE (L"Minutes"), seconds, LOCALIZE (L"Seconds"));

   else if (hours > 0)

      swprintf_s (dest, dest_size_in_wchars, L"%d %s %d %s %d %s", hours, LOCALIZE (L"Hours"), minutes, LOCALIZE (L"Minutes"), seconds, LOCALIZE (L"Seconds"));

   else if (minutes > 0)

      swprintf_s (dest, dest_size_in_wchars, L"%d %s %d %s", minutes, LOCALIZE (L"Minutes"), seconds, LOCALIZE (L"Seconds"));

   else

      swprintf_s (dest, dest_size_in_wchars, L"%d %s", seconds, LOCALIZE (L"Seconds"));

   return; // finished

}

int MonthStringToNumber (wchar_t *month_string)

{

   // helper function to convert a month string to its equivalent number

   if (_wcsnicmp (month_string, L"jan", 3) == 0) return (1); // january

   else if (_wcsnicmp (month_string, L"feb", 3) == 0) return (2); // february

   else if (_wcsnicmp (month_string, L"mar", 3) == 0) return (3); // march

   else if (_wcsnicmp (month_string, L"apr", 3) == 0) return (4); // april

   else if (_wcsnicmp (month_string, L"may", 3) == 0) return (5); // may

   else if (_wcsnicmp (month_string, L"jun", 3) == 0) return (6); // june

   else if (_wcsnicmp (month_string, L"jul", 3) == 0) return (7); // july

   else if (_wcsnicmp (month_string, L"aug", 3) == 0) return (8); // august

   else if (_wcsnicmp (month_string, L"sep", 3) == 0) return (9); // september

   else if (_wcsnicmp (month_string, L"oct", 3) == 0) return (10); // october

   else if (_wcsnicmp (month_string, L"nov", 3) == 0) return (11); // november

   else if (_wcsnicmp (month_string, L"dec", 3) == 0) return (12); // december

   return (0); // month not found or not a month

}

bool GetImageSize (const wchar_t *imagefile_pathname, int *width, int *height)

{

   // routine to get the size of a DDS/JPG/PNG/TGA/BMP image. JPEG code courtesy of wischik.com.

   wchar_t valid_pathname[MAX_PATH];

   unsigned char buffer[26];

   struct _stat fileinfo;

   FILE *fp;

   int length;

   int pos;

   length = wcslen (imagefile_pathname); // get pathname length

   // does the pathname we want end with a wildcard ?

   if ((length > 0) && (imagefile_pathname[length - 1] == L'*'))

   {

      // test if a corresponding .dds, .jpg, .jpeg, .png, .tga or .bmp file exists

      wcsncpy_s (valid_pathname, WCHAR_SIZEOF (valid_pathname), imagefile_pathname, length - 1);

      // try these extensions one after the other...

      wcscpy_s (&valid_pathname[length - 1], WCHAR_SIZEOF (valid_pathname) - (length - 1), L"dds");

      if (_wstat (valid_pathname, &fileinfo) != 0)

      {

         wcscpy_s (&valid_pathname[length - 1], WCHAR_SIZEOF (valid_pathname) - (length - 1), L"jpg");

         if (_wstat (valid_pathname, &fileinfo) != 0)

         {

            wcscpy_s (&valid_pathname[length - 1], WCHAR_SIZEOF (valid_pathname) - (length - 1), L"jpeg");

            if (_wstat (valid_pathname, &fileinfo) != 0)

            {

               wcscpy_s (&valid_pathname[length - 1], WCHAR_SIZEOF (valid_pathname) - (length - 1), L"png");

               if (_wstat (valid_pathname, &fileinfo) != 0)

               {

                  wcscpy_s (&valid_pathname[length - 1], WCHAR_SIZEOF (valid_pathname) - (length - 1), L"tga");

                  if (_wstat (valid_pathname, &fileinfo) != 0)

                  {

                     wcscpy_s (&valid_pathname[length - 1], WCHAR_SIZEOF (valid_pathname) - (length - 1), L"bmp");

                     if (_wstat (valid_pathname, &fileinfo) != 0)

                        return (false); // if none of these extensions match, bomb out

                  }

               }

            }

         }

      }

   }

   else

      wcscpy_s (valid_pathname, WCHAR_SIZEOF (valid_pathname), imagefile_pathname); // the filename we want is known

   // open the file for binary reading first

   _wfopen_s (&fp, valid_pathname, L"rb");

   if (fp == NULL)

      return (false); // if unable to open the file, return FALSE

   // get file length

   fseek (fp, 0, SEEK_END);

   length = ftell (fp);

   fseek (fp, 0, SEEK_SET);

   // if file is not large enough to hold a single chunk of data, it can't possibly be a valid image

   if (length < 26)

   {

      fclose (fp); // so close it

      return (FALSE); // and return FALSE

   }

  // Strategy:

  // reading JPEG dimensions requires scanning through jpeg chunks

  // reading PNG dimensions requires the first 24 bytes of the file

  // reading BMP dimensions requires the first 26 bytes of the file

  // In all formats, the file is at least 26 bytes big, so we'll read that always

   fread (buffer, 26, 1, fp);

   // For DDS files, dimensions are given at bytes 12 (height) and 16 (width)

   if ((buffer[0] == 'D') && (buffer[1] == 'D') && (buffer[2] == 'S') && (buffer[3] == ' '))

   {

      memcpy (width, &buffer[16], sizeof (unsigned long));

      memcpy (height, &buffer[12], sizeof (unsigned long));

      fclose (fp); // close file now

      return (true); // copy out the width and height and return TRUE

   }

   // For JPEGs, we need to read the first 12 bytes of each chunk.

   // We'll read those 12 bytes at buf+2...buf+14, i.e. overwriting the existing buf.

   else if ((buffer[0] == 0xFF) && (buffer[1] == 0xD8) && (buffer[2] == 0xFF))

   {

      pos = 2; // start at the beginning

      // as long as there's the beginning of a new chunk to parse in our buffer...

      while (buffer[2] == 0xFF)

      {

         // is that chunk the one we want ?

         if ((buffer[2 + 1] == 0xC0) || (buffer[2 + 1] == 0xC1) || (buffer[2 + 1] == 0xC2) || (buffer[2 + 1] == 0xC3))

         {

            *height = 256 * (int) buffer[2 + 5] + (int) buffer[2 + 6]; // copy out the height and width

            *width = 256 * (int) buffer[2 + 7] + (int) buffer[2 + 8];

            fclose (fp); // close file now

            return (true); // and return TRUE

         }

         pos += 2 + 256 * (int) buffer[2 + 2] + (int) buffer[2 + 3]; // else increase pos by the size of the chunk

         if (pos >= length)

         {

            fclose (fp); // close file now

            return (false); // stop searching if end of file is reached

         }

         fseek (fp, pos, SEEK_SET); // seek at beginning of next block

         fread (&buffer[2], 10, 1, fp); // and read another 10-byte block

      }

   }

   // PNG: the first frame is by definition an IHDR frame, which gives dimensions

   else if ((buffer[0] == 0x89) && (buffer[1] == 'P') && (buffer[2] == 'N') && (buffer[3] == 'G')

            && (buffer[4] == 0x0D) && (buffer[5] == 0x0A) && (buffer[6] == 0x1A) && (buffer[7] == 0x0A)

            && (buffer[12] == 'I') && (buffer[13] == 'H') && (buffer[14] == 'D') && (buffer[15]=='R'))

   {

      *width = (buffer[16] << 24) | (buffer[17] << 16) | (buffer[18] << 8) | (buffer[19] << 0);

      *height = (buffer[20] << 24) | (buffer[21] << 16) | (buffer[22] << 8) | (buffer[23] << 0);

      fclose (fp); // close file now

      return (true); // copy out the width and height and return TRUE

   }

   // TGA: read the image size from the TGA header

   else if ((buffer[0] == 0x00) && ((buffer[1] == 0x00) || (buffer[1] == 0x01)))

   {

      *width = (buffer[13] << 8) | (buffer[12] << 0);

      *height = (buffer[15] << 8) | (buffer[14] << 0);

      fclose (fp); // close file now

      return (true); // copy out the width and height and return TRUE

   }

   // BMP: read the bitmap file header, then the image header

   else if ((buffer[0] == 'B') && (buffer[1] == 'M')

            && (buffer[6] == 0) && (buffer[7] == 0) && (buffer[8] == 0) && (buffer[9] == 0))

   {

      memcpy (width, &buffer[18], sizeof (unsigned long));

      memcpy (height, &buffer[22], sizeof (unsigned long));

      fclose (fp); // close file now

      return (true); // copy out the width and height and return TRUE

   }

   fclose (fp); // close file now

   return (false); // file is probably not a DDS, BMP, PNG, TGA or JPEG image

}

void Debug_Init (const wchar_t *logfile_name)

{

   // helper function for debug log file initialization

   FILE *fp;

   // build the log file full qualified path name

   swprintf_s (logfile_pathname, WCHAR_SIZEOF (logfile_pathname), L"%s/%s", app_path, logfile_name);

   // open it and erase it

   _wfopen_s (&fp, logfile_pathname, L"wb");

   if (fp != NULL)

   {

      fwprintf_s (fp, L"===LOG FILE RESET===\n"); // write the log initialization string

      fclose (fp); // flush buffers and close file

   }

   return; // finished

}

void Debug_Log (const wchar_t *fmt, ...)

{

   // helper function for debug logging

   FILE *fp;

   va_list argptr;

   // concatenate all the arguments in one string

   va_start (argptr, fmt);

   _vsnwprintf_s (log_message, WCHAR_SIZEOF (log_message), _TRUNCATE, fmt, argptr);

   va_end (argptr);

   // open the log file in append mode

   _wfopen_s (&fp, logfile_pathname, L"ab");

   if (fp != NULL)

   {

      fwprintf_s (fp, log_message); // write the log message

      fclose (fp); // flush buffers and close it

   }

   return; // finished

}

const wchar_t *GetLastNetworkError (void)

{

   // this function retrieves and translates the last WSA error code into a full text string

   static const wsaerror_t wsa_errors[] =

   {

      {6, L"WSA_INVALID_HANDLE: Specified event object handle is invalid. [An application attempts to use an event object, but the specified handle is not valid. Note that this error is returned by the operating system, so the error number may change in future releases of Windows.]"},

      {8, L"WSA_NOT_ENOUGH_MEMORY: Insufficient memory available. [An application used a Windows Sockets function that directly maps to a Windows function. The Windows function is indicating a lack of required memory resources. Note that this error is returned by the operating system, so the error number may change in future releases of Windows.]"},

      {87, L"WSA_INVALID_PARAMETER: One or more parameters are invalid. [An application used a Windows Sockets function which directly maps to a Windows function. The Windows function is indicating a problem with one or more parameters. Note that this error is returned by the operating system, so the error number may change in future releases of Windows.]"},

      {995, L"WSA_OPERATION_ABORTED: Overlapped operation aborted. [An overlapped operation was canceled due to the closure of the socket, or the execution of the SIO_FLUSH command in WSAIoctl. Note that this error is returned by the operating system, so the error number may change in future releases of Windows.]"},

      {996, L"WSA_IO_INCOMPLETE: Overlapped I/O event object not in signaled state. [The application has tried to determine the status of an overlapped operation which is not yet completed. Applications that use WSAGetOverlappedResult (with the fWait flag set to FALSE) in a polling mode to determine when an overlapped operation has completed, get this error code until the operation is complete. Note that this error is returned by the operating system, so the error number may change in future releases of Windows.]"},

      {997, L"WSA_IO_PENDING: Overlapped operations will complete later. [The application has initiated an overlapped operation that cannot be completed immediately. A completion indication will be given later when the operation has been completed. Note that this error is returned by the operating system, so the error number may change in future releases of Windows.]"},

      {10004, L"WSAEINTR: Interrupted function call. [A blocking operation was interrupted by a call to WSACancelBlockingCall.]"},

      {10009, L"WSAEBADF: File handle is not valid. [The file handle supplied is not valid.]"},

      {10013, L"WSAEACCES: Permission denied. [An attempt was made to access a socket in a way forbidden by its access permissions. An example is using a broadcast address for sendto without broadcast permission being set using setsockopt(SO_BROADCAST). Another possible reason for the WSAEACCES error is that when the bind function is called (on Windows NT 4 SP4 or later), another application, service, or kernel mode driver is bound to the same address with exclusive access. Such exclusive access is a new feature of Windows NT 4 SP4 and later, and is implemented by using the SO_EXCLUSIVEADDRUSE option.]"},

      {10014, L"WSAEFAULT: Bad address. [The system detected an invalid pointer address in attempting to use a pointer argument of a call. This error occurs if an application passes an invalid pointer value, or if the length of the buffer is too small. For instance, if the length of an argument, which is a sockaddr structure, is smaller than the sizeof(sockaddr).]"},

      {10022, L"WSAEINVAL: Invalid argument. [Some invalid argument was supplied (for example, specifying an invalid level to the setsockopt function). In some instances, it also refers to the current state of the socket—for instance, calling accept on a socket that is not listening.]"},

      {10024, L"WSAEMFILE: Too many open files. [Too many open sockets. Each implementation may have a maximum number of socket handles available, either globally, per process, or per thread.]"},

      {10035, L"WSAEWOULDBLOCK: Resource temporarily unavailable. [This error is returned from operations on nonblocking sockets that cannot be completed immediately, for example recv when no data is queued to be read from the socket. It is a nonfatal error, and the operation should be retried later. It is normal for WSAEWOULDBLOCK to be reported as the result from calling connect on a nonblocking SOCK_STREAM socket, since some time must elapse for the connection to be established.]"},

      {10036, L"WSAEINPROGRESS: Operation now in progress. [A blocking operation is currently executing. Windows Sockets only allows a single blocking operation—per- task or thread—to be outstanding, and if any other function call is made (whether or not it references that or any other socket) the function fails with the WSAEINPROGRESS error.]"},

      {10037, L"WSAEALREADY: Operation already in progress. [An operation was attempted on a nonblocking socket with an operation already in progress—that is, calling connect a second time on a nonblocking socket that is already connecting, or canceling an asynchronous request (WSAAsyncGetXbyY) that has already been canceled or completed.]"},

      {10038, L"WSAENOTSOCK: Socket operation on nonsocket. [An operation was attempted on something that is not a socket. Either the socket handle parameter did not reference a valid socket, or for select, a member of an fd_set was not valid.]"},

      {10039, L"WSAEDESTADDRREQ: Destination address required. [A required address was omitted from an operation on a socket. For example, this error is returned if sendto is called with the remote address of ADDR_ANY.]"},

      {10040, L"WSAEMSGSIZE: Message too long. [A message sent on a datagram socket was larger than the internal message buffer or some other network limit, or the buffer used to receive a datagram was smaller than the datagram itself.]"},

      {10041, L"WSAEPROTOTYPE: Protocol wrong type for socket. [A protocol was specified in the socket function call that does not support the semantics of the socket type requested. For example, the ARPA Internet UDP protocol cannot be specified with a socket type of SOCK_STREAM.]"},

      {10042, L"WSAENOPROTOOPT: Bad protocol option. [An unknown, invalid or unsupported option or level was specified in a getsockopt or setsockopt call.]"},

      {10043, L"WSAEPROTONOSUPPORT: Protocol not supported. [The requested protocol has not been configured into the system, or no implementation for it exists. For example, a socket call requests a SOCK_DGRAM socket, but specifies a stream protocol.]"},