Upgrade WX to r74856, mainly to support @2x.

Externals/wxWidgets3/include/wx/msw/private/pipestream.h

@@ -0,0 +1,50 @@
+///////////////////////////////////////////////////////////////////////////////
+// Name:        wx/msw/private/pipestream.h
+// Purpose:     MSW wxPipeInputStream and wxPipeOutputStream declarations
+// Author:      Vadim Zeitlin
+// Created:     2013-06-08 (extracted from src/msw/utilsexc.cpp)
+// Copyright:   (c) 2013 Vadim Zeitlin <vadim@wxwidgets.org>
+// Licence:     wxWindows licence
+///////////////////////////////////////////////////////////////////////////////
+
+#ifndef _WX_MSW_PRIVATE_PIPESTREAM_H_
+#define _WX_MSW_PRIVATE_PIPESTREAM_H_
+
+class wxPipeInputStream : public wxInputStream
+{
+public:
+    wxEXPLICIT wxPipeInputStream(HANDLE hInput);
+    virtual ~wxPipeInputStream();
+
+    // returns true if the pipe is still opened
+    bool IsOpened() const { return m_hInput != INVALID_HANDLE_VALUE; }
+
+    // returns true if there is any data to be read from the pipe
+    virtual bool CanRead() const;
+
+protected:
+    virtual size_t OnSysRead(void *buffer, size_t len);
+
+protected:
+    HANDLE m_hInput;
+
+    wxDECLARE_NO_COPY_CLASS(wxPipeInputStream);
+};
+
+class wxPipeOutputStream: public wxOutputStream
+{
+public:
+    wxEXPLICIT wxPipeOutputStream(HANDLE hOutput);
+    virtual ~wxPipeOutputStream() { Close(); }
+    bool Close();
+
+protected:
+    size_t OnSysWrite(const void *buffer, size_t len);
+
+protected:
+    HANDLE m_hOutput;
+
+    wxDECLARE_NO_COPY_CLASS(wxPipeOutputStream);
+};
+
+#endif // _WX_MSW_PRIVATE_PIPESTREAM_H_