Added Shiboken buffer interface.

This interface is just a wrapper to the differents API's provided by Python
to deal with memory buffers in various versions of Python, so is recommended
to use this API to deal with Python memory buffers instead of the CPython API.

If you want to have a Python buffer as argument of any function just change
the argument type to "PyBuffer" and the generator will handle it right regarding
to type checking.

Reviewer: Renato Araújo <renato.filho@openbossa.org>
          Luciano Wolf <luciano.wolf@openbossa.org>

4 files changed, 123 insertions, 0 deletions

diff --git a/libshiboken/CMakeLists.txt b/libshiboken/CMakeLists.txt
index 0cf3f3d21..38aa46bc7 100644
--- a/libshiboken/CMakeLists.txt
+++ b/libshiboken/CMakeLists.txt
@@ -29,6 +29,7 @@ sbkenum.cpp
 bindingmanager.cpp
 threadstatesaver.cpp
 typeresolver.cpp
+shibokenbuffer.cpp
 )
 
 include_directories(${CMAKE_CURRENT_SOURCE_DIR}
@@ -55,6 +56,7 @@ install(FILES
         shibokenmacros.h
         threadstatesaver.h
         typeresolver.h
+        shibokenbuffer.h
         DESTINATION include/shiboken${shiboken_SUFFIX})
 install(TARGETS libshiboken EXPORT shiboken
                             LIBRARY DESTINATION "${LIB_INSTALL_DIR}"
diff --git a/libshiboken/shiboken.h b/libshiboken/shiboken.h
index 6a2df306c..f2087fe0e 100644
--- a/libshiboken/shiboken.h
+++ b/libshiboken/shiboken.h
@@ -34,6 +34,7 @@
 #include "sbkenum.h"
 #include "shibokenmacros.h"
 #include "typeresolver.h"
+#include "shibokenbuffer.h"
 
 #endif // SHIBOKEN_H
 
diff --git a/libshiboken/shibokenbuffer.cpp b/libshiboken/shibokenbuffer.cpp
new file mode 100644
index 000000000..67b3ba726
--- /dev/null
+++ b/libshiboken/shibokenbuffer.cpp
@@ -0,0 +1,52 @@
+/*
+* This file is part of the Shiboken Python Bindings Generator project.
+*
+* Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+*
+* Contact: PySide team <contact@pyside.org>
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU Lesser General Public
+* License as published by the Free Software Foundation; either
+* version 2.1 of the License, or (at your option) any later version.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+* Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser General Public
+* License along with this library; if not, write to the Free Software
+* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#include "shibokenbuffer.h"
+#include <cstdlib>
+#include <cstring>
+
+bool Shiboken::Buffer::checkType(PyObject* pyObj)
+{
+    return PyObject_CheckReadBuffer(pyObj);
+}
+
+void* Shiboken::Buffer::getPointer(PyObject* pyObj, Py_ssize_t* size)
+{
+    const void* buffer = 0;
+    Py_ssize_t bufferSize = 0;
+
+    PyObject_AsReadBuffer(pyObj, &buffer, &bufferSize);
+
+    if (size)
+        *size = bufferSize;
+    return const_cast<void*>(buffer);
+}
+
+PyObject* Shiboken::Buffer::newObject(void* memory, Py_ssize_t size, Type type)
+{
+    return type == ReadOnly ? PyBuffer_FromMemory(memory, size) : PyBuffer_FromReadWriteMemory(memory, size);
+}
+
+PyObject* Shiboken::Buffer::newObject(const void* memory, Py_ssize_t size)
+{
+    return newObject(const_cast<void*>(memory), size, ReadOnly);
+}
diff --git a/libshiboken/shibokenbuffer.h b/libshiboken/shibokenbuffer.h
new file mode 100644
index 000000000..8f8e91dbe
--- /dev/null
+++ b/libshiboken/shibokenbuffer.h
@@ -0,0 +1,68 @@
+/*
+* This file is part of the Shiboken Python Bindings Generator project.
+*
+* Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+*
+* Contact: PySide team <contact@pyside.org>
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU Lesser General Public
+* License as published by the Free Software Foundation; either
+* version 2.1 of the License, or (at your option) any later version.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+* Lesser General Public License for more details.
+*
+* You should have received a copy of the GNU Lesser General Public
+* License along with this library; if not, write to the Free Software
+* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef SHIBOKEN_BUFFER_H
+#define SHIBOKEN_BUFFER_H
+
+#include <Python.h>
+#include "shibokenmacros.h"
+
+namespace Shiboken
+{
+
+namespace Buffer
+{
+    enum Type {
+        ReadOnly,
+        WriteOnly,
+        ReadWrite
+    };
+
+    /**
+     * Creates a new Python buffer pointing to a contiguous memory block at
+     * \p memory of size \p size.
+     */
+    LIBSHIBOKEN_API PyObject* newObject(void* memory, Py_ssize_t size, Type type);
+
+    /**
+     * Creates a new <b>read only</b> Python buffer pointing to a contiguous memory block at
+     * \p memory of size \p size.
+     */
+    LIBSHIBOKEN_API PyObject* newObject(const void* memory, Py_ssize_t size);
+
+    /**
+     * Check if is ok to use \p pyObj as argument in all function under Shiboken::Buffer namespace.
+     */
+    LIBSHIBOKEN_API bool checkType(PyObject* pyObj);
+
+    /**
+     * Returns a pointer to the memory pointed by the buffer \p pyObj, \p size is filled with the buffer
+     * size if not null.
+     *
+     * If the \p pyObj is a non-contiguous buffer a Python error is set.
+     */
+    LIBSHIBOKEN_API void* getPointer(PyObject* pyObj, Py_ssize_t* size = 0);
+
+} // namespace Buffer
+} // namespace Shiboken
+
+#endif
\ No newline at end of file