diff options
Diffstat (limited to 'sources/pyside6/libpyside/pysideqenum.cpp')
| -rw-r--r-- | sources/pyside6/libpyside/pysideqenum.cpp | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/sources/pyside6/libpyside/pysideqenum.cpp b/sources/pyside6/libpyside/pysideqenum.cpp new file mode 100644 index 000000000..c0479160f --- /dev/null +++ b/sources/pyside6/libpyside/pysideqenum.cpp @@ -0,0 +1,197 @@ +// Copyright (C) 2020 The Qt Company Ltd. +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only + +#include <shiboken.h> + +#include "pysideqenum.h" +#include "dynamicqmetaobject.h" +#include "pyside_p.h" + + +/////////////////////////////////////////////////////////////// +// +// PYSIDE-957: Create QEnum dynamically from Python Enum +// +// +extern "C" { + +using namespace Shiboken; + +static PyObject *analyzePyEnum(PyObject *pyenum) +{ + /* + * This is the straight-forward implementation of QEnum/QFlag. It does no + * longer create an equivalent Qt enum but takes the Python enum as-is. + * + * It parses an Enum/Flag derived Python enum completely so that + * registering can be done without error checks. This would be impossible + * in MetaObjectBuilderPrivate::parsePythonType. + */ + AutoDecRef members(PyObject_GetAttr(pyenum, Shiboken::PyMagicName::members())); + if (members.isNull()) + return nullptr; + AutoDecRef items(PyMapping_Items(members)); + if (items.isNull()) + return nullptr; + int iflag = PySide::QEnum::isFlag(pyenum); + if (iflag < 0) + return nullptr; + Py_ssize_t nr_items = PySequence_Length(items); + if (nr_items < 0) + return nullptr; + + for (Py_ssize_t idx = 0; idx < nr_items; ++idx) { + AutoDecRef item(PySequence_GetItem(items, idx)); + if (item.isNull()) + return nullptr; + + // The item should be a 2-element sequence of the key name and an + // object containing the value. + AutoDecRef key(PySequence_GetItem(item, 0)); + AutoDecRef member(PySequence_GetItem(item, 1)); + if (key.isNull() || member.isNull()) + return nullptr; + if (!Shiboken::String::check(key)) { + // '%.200s' is the safety stringbuffer size of most CPython functions. + PyErr_Format(PyExc_TypeError, + "QEnum expected a string mapping as __members__, got '%.200s'", + Py_TYPE(key)->tp_name); + return nullptr; + } + + // Get the value. + AutoDecRef value(PyObject_GetAttr(member, Shiboken::PyName::value())); + if (value.isNull()) + return nullptr; + if (!PyLong_Check(value)) { + PyErr_Format(PyExc_TypeError, + "QEnum expected an int value as '%.200s', got '%.200s'", + Shiboken::String::toCString(key), Py_TYPE(value)->tp_name); + return nullptr; + } + } + Py_RETURN_NONE; +} + +static Py_ssize_t get_lineno() +{ + PyObject *frame = reinterpret_cast<PyObject *>(PyEval_GetFrame()); // borrowed ref + AutoDecRef ob_lineno(PyObject_GetAttr(frame, Shiboken::PyName::f_lineno())); + if (ob_lineno.isNull() || !PyLong_Check(ob_lineno)) + return -1; + return PyLong_AsSsize_t(ob_lineno); +} + +static bool is_module_code() +{ + PyObject *frame = reinterpret_cast<PyObject *>(PyEval_GetFrame()); // borrowed ref + AutoDecRef ob_code(PyObject_GetAttr(frame, Shiboken::PyName::f_code())); + if (ob_code.isNull()) + return false; + AutoDecRef ob_name(PyObject_GetAttr(ob_code, Shiboken::PyName::co_name())); + if (ob_name.isNull()) + return false; + const char *codename = Shiboken::String::toCString(ob_name); + return strcmp(codename, "<module>") == 0; +} + +} // extern "C" + +namespace PySide::QEnum { + +static std::map<int, PyObject *> enumCollector; + +int isFlag(PyObject *obType) +{ + /* + * Find out if this is an Enum or a Flag derived class. + * It checks also if things come from the enum module and if it is + * an Enum or Flag class at all. + * + * The function is called in MetaObjectBuilderPrivate::parsePythonType + * again to obtain the flag value. + */ + int res = enumIsFlag(obType); + if (res < 0) { + auto *type = reinterpret_cast<PyTypeObject *>(obType); + PyErr_Format(PyExc_TypeError, "type %.200s does not inherit from 'Enum' or 'Flag'", + type->tp_name); + return -1; + } + return bool(res); +} + +PyObject *QEnumMacro(PyObject *pyenum, bool flag) +{ + /* + * This is the official interface of 'QEnum'. It first calls 'analyzePyEnum'. + * When called as toplevel enum, it simply returns after some checks. + * Otherwise, 'pyenum' is stored for later use by the meta class registation. + */ + int computedFlag = isFlag(pyenum); + if (computedFlag < 0) + return nullptr; + if (bool(computedFlag) != flag) { + AutoDecRef name(PyObject_GetAttr(pyenum, PyMagicName::qualname())); + auto cname = String::toCString(name); + const char *e = "Enum"; + const char *f = "Flag"; + PyErr_Format(PyExc_TypeError, "expected '%s' but got '%s' (%.200s)", + flag ? f : e, flag ? e : f, cname); + return nullptr; + } + auto ok = analyzePyEnum(pyenum); + if (ok == nullptr) + return nullptr; + if (is_module_code()) { + // This is a toplevel enum which we resolve immediately. + Py_INCREF(pyenum); + return pyenum; + } + + Py_ssize_t lineno = get_lineno(); + if (lineno < 0) + return nullptr; + // Handle the rest via line number and the meta class. + Py_INCREF(pyenum); + Py_XDECREF(enumCollector[lineno]); + enumCollector[lineno] = pyenum; + Py_RETURN_NONE; +} + +std::vector<PyObject *> resolveDelayedQEnums(PyTypeObject *containerType) +{ + /* + * This is the internal interface of 'QEnum'. + * It is called at the end of the meta class call 'SbkObjectType_tp_new' via + * MetaObjectBuilderPrivate::parsePythonType and resolves the collected + * Python Enum arguments. The result is then registered. + */ + if (enumCollector.empty()) + return {}; + PyObject *obContainerType = reinterpret_cast<PyObject *>(containerType); + Py_ssize_t lineno = get_lineno(); + + std::vector<PyObject *> result; + + auto it = enumCollector.begin(); + while (it != enumCollector.end()) { + int nr = it->first; + PyObject *pyenum = it->second; + if (nr >= lineno) { + AutoDecRef name(PyObject_GetAttr(pyenum, PyMagicName::name())); + if (name.isNull() || PyObject_SetAttr(obContainerType, name, pyenum) < 0) + return {}; + result.push_back(pyenum); + it = enumCollector.erase(it); + } else { + ++it; + } + } + return result; +} + +} // namespace Shiboken::Enum + +// +/////////////////////////////////////////////////////////////// |