pyobject_plus.cpp

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/** @file
 *  @author Bram de Greve (bram@cocamware.com)
 *  @author Tom De Muer (tom@cocamware.com)
 *
 *  *** BEGIN LICENSE INFORMATION ***
 *  
 *  The contents of this file are subject to the Common Public Attribution License 
 *  Version 1.0 (the "License"); you may not use this file except in compliance with 
 *  the License. You may obtain a copy of the License at 
 *  http://lass.sourceforge.net/cpal-license. The License is based on the 
 *  Mozilla Public License Version 1.1 but Sections 14 and 15 have been added to cover 
 *  use of software over a computer network and provide for limited attribution for 
 *  the Original Developer. In addition, Exhibit A has been modified to be consistent 
 *  with Exhibit B.
 *  
 *  Software distributed under the License is distributed on an "AS IS" basis, WITHOUT 
 *  WARRANTY OF ANY KIND, either express or implied. See the License for the specific 
 *  language governing rights and limitations under the License.
 *  
 *  The Original Code is LASS - Library of Assembled Shared Sources.
 *  
 *  The Initial Developer of the Original Code is Bram de Greve and Tom De Muer.
 *  The Original Developer is the Initial Developer.
 *  
 *  All portions of the code written by the Initial Developer are:
 *  Copyright (C) 2004-2025 the Initial Developer.
 *  All Rights Reserved.
 *  
 *  Contributor(s):
 *
 *  Alternatively, the contents of this file may be used under the terms of the 
 *  GNU General Public License Version 2 or later (the GPL), in which case the 
 *  provisions of GPL are applicable instead of those above.  If you wish to allow use
 *  of your version of this file only under the terms of the GPL and not to allow 
 *  others to use your version of this file under the CPAL, indicate your decision by 
 *  deleting the provisions above and replace them with the notice and other 
 *  provisions required by the GPL License. If you do not delete the provisions above,
 *  a recipient may use your version of this file under either the CPAL or the GPL.
 *  
 *  *** END LICENSE INFORMATION ***
 */
 
 
 
#include "python_common.h"
#include "pyobject_plus.h"
#include "py_tuple.h"
#include "pyiteratorrange.h"
#include <iostream>
 
namespace lass
{
namespace python
{
 
impl::ClassDefinition PyObjectPlus::_lassPyClassDef(
    "PyObjectPlus", 0, sizeof(PyObjectPlus), 0, 0, &PyObjectPlus::_lassPyClassRegisterHook);
 
/** This function can be used to execute some code at injection time.
 *  By default it doens't do anything, but you can override it for
 *  any type.  Be aware that the top level implementation is the
 *  only one that counts.  Consider it as a 'virtual' function at
 *  static level
 */
void PyObjectPlus::_lassPyClassRegisterHook()
{
}
 
PyObjectPlus::PyObjectPlus()
{
    // initializing the type to NULL, when the object is exported to python the type is fixed
    this->ob_type = NULL;
    LockGIL lock;
    _Py_NewReference( this );
};
 
PyObjectPlus::~PyObjectPlus()
{
    LASS_ASSERT(Py_REFCNT(this) <= 1);
    if (Py_REFCNT(this) > 1)
    {
        std::cerr << "[LASS RUN MSG] DANGLING REFERENCE to lass::python::PyObjectPlus" << std::endl;
    }
};
 
PyObjectPlus::PyObjectPlus(const PyObjectPlus& other)
{
    LockGIL lock;
    this->ob_type = other.ob_type;
    Py_XINCREF(this->ob_type);
    _Py_NewReference( this );
}
 
PyObjectPlus& PyObjectPlus::operator =([[maybe_unused]] const PyObjectPlus& iOther)
{
    LASS_ASSERT(!this->ob_type || this->ob_type == iOther.ob_type);
    return *this;
}
 
// --- impl ----------------------------------------------------------------------------------------
 
namespace impl
{
 
/** @internal
*/
bool checkSequenceSize(PyObject* obj, Py_ssize_t expectedSize)
{
    LockGIL lock;
    if (!PySequence_Check(obj))
    {
        PyErr_SetString(PyExc_TypeError, "not a python sequence (tuple, list, ...)");
        return false;
    }
    const Py_ssize_t size = PySequence_Size(obj);
    if (size != expectedSize)
    {
        std::ostringstream buffer;
        buffer << "tuple/list is not of expected size " << expectedSize << " (size is " << size << ")";
        PyErr_SetString(PyExc_TypeError, buffer.str().c_str());
        return false;
    }
    return true;
}
 
/** @internal
 *  Check that @a obj is a sequence, and return it as a "FAST sequence"
 *  so that you can use PySequence_Fast_GET_ITEM to get its items with borrowed references.
 */
TPyObjPtr checkedFastSequence(PyObject* obj)
{
    LockGIL lock;
    return TPyObjPtr(PySequence_Fast(obj, "expected a sequence (tuple, list, ...)"));
}
 
/** @internal
 *  Check that @a obj is a sequence and of expected size, and return it as a "FAST sequence"
 *  so that you can use PySequence_Fast_GET_ITEM to get its items with borrowed references.
 */
TPyObjPtr checkedFastSequence(PyObject* obj, Py_ssize_t expectedSize)
{
    LockGIL lock;
    TPyObjPtr result = checkedFastSequence(obj);
    if (result)
    {
        const Py_ssize_t size = PySequence_Fast_GET_SIZE(result.get());
        if (size != expectedSize)
        {
            std::ostringstream buffer;
            buffer << "expected a sequence of size " << expectedSize << " (your size is " << size << ")";
            PyErr_SetString(PyExc_TypeError, buffer.str().c_str());
            result.reset();
        }
    }
    return result;
}
 
/** @internal
 *  Check that @a obj is a sequence and of expected size, and return it as a "FAST sequence"
 *  so that you can use PySequence_Fast_GET_ITEM to get its items with borrowed references.
 */
TPyObjPtr checkedFastSequence(PyObject* obj, Py_ssize_t minimumSize, Py_ssize_t maximumSize)
{
    LockGIL lock;
    TPyObjPtr result = checkedFastSequence(obj);
    if (result)
    {
        const Py_ssize_t size = PySequence_Fast_GET_SIZE(result.get());
        if (size < minimumSize || size > maximumSize)
        {
            std::ostringstream buffer;
            buffer << "expected a sequence of size between " << minimumSize << " and " << maximumSize
                << " inclusive (your size is " << size << ")";
            PyErr_SetString(PyExc_TypeError, buffer.str().c_str());
            result.reset();
        }
    }
    return result;
}
 
/** Here, we try to fix some lifetime issues to guarantee some lifetime requirements on self.
 */
PyObject* establishMagicalBackLinks(PyObject* result, PyObject* self)
{
    if (!result)
    {
        return 0;
    }
    if (PyIteratorRange::_lassPyClassDef.isFrozen_ && result->ob_type == PyIteratorRange::_lassPyClassDef.type())
    {
        LockGIL lock;
        PyIteratorRange* iter = static_cast<PyIteratorRange*>(result);
        if (!iter->owner())
        {
            iter->setOwner(fromNakedToSharedPtrCast<PyObject>(self));
        }
    }
    return result;
}
 
}
}
}
 
// EOF