/// <summary>
/// Initializes a new instance of the <see cref="AnsiStringMarshaller"/>.
/// </summary>
/// <param name="str">The string to marshal.</param>
/// <param name="buffer">Buffer that may be used for marshalling.</param>
/// <remarks>
/// The <paramref name="buffer"/> must not be movable - that is, it should not be
/// on the managed heap or it should be pinned.
/// <seealso cref="CustomTypeMarshallerFeatures.CallerAllocatedBuffer"/>
/// </remarks>
public AnsiStringMarshaller(string?str, Span <byte> buffer)
{
_allocated = null;
if (str is null)
{
_span = default;
return;
}
// + 1 for null terminator
int maxByteCount = (str.Length + 1) * Marshal.SystemMaxDBCSCharSize + 1;
if (buffer.Length >= maxByteCount)
{
Marshal.StringToAnsiString(str, (byte *)Unsafe.AsPointer(ref MemoryMarshal.GetReference(buffer)), buffer.Length);
_span = buffer;
}
else
{
_allocated = (byte *)Marshal.StringToCoTaskMemAnsi(str);
_span = default;
}
}