/// <summary>
/// Scans the string looking for unmappable characters in the ASCII set, and replaces
/// them with '?'.
/// </summary>
/// <param name="inputString">A unicode string with unknown characters.</param>
/// <param name="charCount">The length of the string to sanitize.</param>
/// <param name="allocedMemory">On output, a value that needs to be freed. Only used
/// if there are any untranslaable characters.</param>
/// <returns>A string that has all legal ASCII characters.</returns>
private unsafe char *SanitizeString(char *inputString, int charCount, out IntPtr allocedMemory)
{
allocedMemory = IntPtr.Zero;
bool needToDuplicate = false;
char *returnString = inputString;
for (int i = 0; i < charCount; ++i)
{
if (inputString[i] > 127)
{
needToDuplicate = true;
break;
}
}
if (needToDuplicate)
{
allocedMemory = LibraryHelpers.MarshalAllocHGlobal(charCount);
returnString = (char *)allocedMemory;
char *dest = returnString;
for (int i = 0; i < charCount; ++i)
{
dest[i] = inputString[i] > 127 ? '?' : inputString[i];
}
}
return(returnString);
}
