McRogueFace/src/PyRAII.h

138 lines
3.9 KiB
C++

#pragma once
#include "Python.h"
#include <utility>
namespace PyRAII {
// RAII wrapper for PyObject* that automatically manages reference counting
class PyObjectRef {
private:
PyObject* ptr;
public:
// Constructors
PyObjectRef() : ptr(nullptr) {}
explicit PyObjectRef(PyObject* p, bool steal_ref = false) : ptr(p) {
if (ptr && !steal_ref) {
Py_INCREF(ptr);
}
}
// Copy constructor
PyObjectRef(const PyObjectRef& other) : ptr(other.ptr) {
if (ptr) {
Py_INCREF(ptr);
}
}
// Move constructor
PyObjectRef(PyObjectRef&& other) noexcept : ptr(other.ptr) {
other.ptr = nullptr;
}
// Destructor
~PyObjectRef() {
Py_XDECREF(ptr);
}
// Copy assignment
PyObjectRef& operator=(const PyObjectRef& other) {
if (this != &other) {
Py_XDECREF(ptr);
ptr = other.ptr;
if (ptr) {
Py_INCREF(ptr);
}
}
return *this;
}
// Move assignment
PyObjectRef& operator=(PyObjectRef&& other) noexcept {
if (this != &other) {
Py_XDECREF(ptr);
ptr = other.ptr;
other.ptr = nullptr;
}
return *this;
}
// Access operators
PyObject* get() const { return ptr; }
PyObject* operator->() const { return ptr; }
PyObject& operator*() const { return *ptr; }
operator bool() const { return ptr != nullptr; }
// Release ownership (for returning to Python)
PyObject* release() {
PyObject* temp = ptr;
ptr = nullptr;
return temp;
}
// Reset with new pointer
void reset(PyObject* p = nullptr, bool steal_ref = false) {
if (p != ptr) {
Py_XDECREF(ptr);
ptr = p;
if (ptr && !steal_ref) {
Py_INCREF(ptr);
}
}
}
};
// Helper class for managing PyTypeObject* references from module lookups
class PyTypeRef {
private:
PyTypeObject* type;
public:
PyTypeRef() : type(nullptr) {}
explicit PyTypeRef(const char* typeName, PyObject* module) {
type = (PyTypeObject*)PyObject_GetAttrString(module, typeName);
// GetAttrString returns a new reference, so we own it
}
~PyTypeRef() {
Py_XDECREF((PyObject*)type);
}
// Delete copy operations to prevent accidental reference issues
PyTypeRef(const PyTypeRef&) = delete;
PyTypeRef& operator=(const PyTypeRef&) = delete;
// Allow move operations
PyTypeRef(PyTypeRef&& other) noexcept : type(other.type) {
other.type = nullptr;
}
PyTypeRef& operator=(PyTypeRef&& other) noexcept {
if (this != &other) {
Py_XDECREF((PyObject*)type);
type = other.type;
other.type = nullptr;
}
return *this;
}
PyTypeObject* get() const { return type; }
PyTypeObject* operator->() const { return type; }
operator bool() const { return type != nullptr; }
};
// Convenience function to create a new object with RAII
template<typename PyObjType>
PyObjectRef createObject(const char* typeName, PyObject* module) {
PyTypeRef type(typeName, module);
if (!type) {
return PyObjectRef();
}
PyObject* obj = type->tp_alloc(type.get(), 0);
// tp_alloc returns a new reference, so we steal it
return PyObjectRef(obj, true);
}
}