Implement proper void pointer (void*) support

This change introduces a new type into the shiboken2 module which is
imported by calling "import PySide2.support.VoidPtr".

The type takes care of conversions from / to void* values in function
signatures.

Creating an instance can be done by passing either a shiboken wrapped
object, or an integer representing an address, or a python object that
implements the buffer interface.

For example, this is useful for passing numpy arrays to C OpenGL
functions that take void* parameters. First you convert the array into
a bytestring (using numpy.array.tobytes(), then you instantiate a
VoidPtr from that bytestring, and finally you pass it along to a GL
function.

One corner case that is currently not supported is void** parameters.

Change-Id: I01e291d6856cb6bd8b5175adc3ead6b728036535
Reviewed-by: Christian Tismer <tismer@stackless.com>

1 files changed, 9 insertions, 1 deletions

diff --git a/sources/pyside2/PySide2/support/__init__.py b/sources/pyside2/PySide2/support/__init__.py
index b2085d892..6a6d267b6 100644
--- a/sources/pyside2/PySide2/support/__init__.py
+++ b/sources/pyside2/PySide2/support/__init__.py
@@ -37,4 +37,12 @@
 ##
 #############################################################################
 
-# This file has intentionally no content.
+# Import VoidPtr type to expose it under PySide2.support.VoidPtr
+try:
+    # The normal import statement when PySide2 is installed.
+    from PySide2.shiboken2 import VoidPtr
+except ImportError:
+    # When running make test in shiboken build dir, or when running testrunner.py,
+    # shiboken2 is not part of the PySide2 module, so it needs to be imported as a standalone
+    # module.
+    from shiboken2 import VoidPtr