From d28601d504dff57c49089f3adcaf0dce83893d83 Mon Sep 17 00:00:00 2001 From: Peter Eisentraut Date: Wed, 5 Mar 2025 17:38:06 +0100 Subject: [PATCH v3 1/2] Prepare for Python "Limited API" in PL/Python Using the Python Limited API would allow building PL/Python against any Python 3.x version and using another Python 3.x version at run time. This commit does not activate that, but it prepares the code to only use APIs supported by the Limited API. Implementation details: - Convert static types to heap types (https://docs.python.org/3/howto/isolating-extensions.html#heap-types). - Replace PyRun_String() with component functions. - Replace PyList_SET_ITEM() with PyList_SetItem(). Discussion: https://www.postgresql.org/message-id/flat/ee410de1-1e0b-4770-b125-eeefd4726a24@eisentraut.org --- src/pl/plpython/plpy_cursorobject.c | 84 +++++++++++++++------ src/pl/plpython/plpy_planobject.c | 70 +++++++++++------ src/pl/plpython/plpy_procedure.c | 5 +- src/pl/plpython/plpy_resultobject.c | 109 +++++++++++++++++---------- src/pl/plpython/plpy_subxactobject.c | 46 ++++++----- src/pl/plpython/plpy_typeio.c | 6 +- 6 files changed, 213 insertions(+), 107 deletions(-) diff --git a/src/pl/plpython/plpy_cursorobject.c b/src/pl/plpython/plpy_cursorobject.c index bb3fa8a3909..1c6be756120 100644 --- a/src/pl/plpython/plpy_cursorobject.c +++ b/src/pl/plpython/plpy_cursorobject.c @@ -20,7 +20,7 @@ #include "utils/memutils.h" static PyObject *PLy_cursor_query(const char *query); -static void PLy_cursor_dealloc(PyObject *arg); +static void PLy_cursor_dealloc(PLyCursorObject *self); static PyObject *PLy_cursor_iternext(PyObject *self); static PyObject *PLy_cursor_fetch(PyObject *self, PyObject *args); static PyObject *PLy_cursor_close(PyObject *self, PyObject *unused); @@ -33,22 +33,43 @@ static PyMethodDef PLy_cursor_methods[] = { {NULL, NULL, 0, NULL} }; -static PyTypeObject PLy_CursorType = { - PyVarObject_HEAD_INIT(NULL, 0) - .tp_name = "PLyCursor", - .tp_basicsize = sizeof(PLyCursorObject), - .tp_dealloc = PLy_cursor_dealloc, - .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, - .tp_doc = PLy_cursor_doc, - .tp_iter = PyObject_SelfIter, - .tp_iternext = PLy_cursor_iternext, - .tp_methods = PLy_cursor_methods, +static PyType_Slot PLyCursor_slots[] = +{ + { + Py_tp_dealloc, PLy_cursor_dealloc + }, + { + Py_tp_doc, (char *) PLy_cursor_doc + }, + { + Py_tp_iter, PyObject_SelfIter + }, + { + Py_tp_iternext, PLy_cursor_iternext + }, + { + Py_tp_methods, PLy_cursor_methods + }, + { + 0, NULL + } }; +static PyType_Spec PLyCursor_spec = +{ + .name = "PLyCursor", + .basicsize = sizeof(PLyCursorObject), + .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, + .slots = PLyCursor_slots, +}; + +static PyTypeObject *PLy_CursorType; + void PLy_cursor_init_type(void) { - if (PyType_Ready(&PLy_CursorType) < 0) + PLy_CursorType = (PyTypeObject *) PyType_FromSpec(&PLyCursor_spec); + if (!PLy_CursorType) elog(ERROR, "could not initialize PLy_CursorType"); } @@ -80,8 +101,12 @@ PLy_cursor_query(const char *query) volatile MemoryContext oldcontext; volatile ResourceOwner oldowner; - if ((cursor = PyObject_New(PLyCursorObject, &PLy_CursorType)) == NULL) + if ((cursor = PyObject_New(PLyCursorObject, PLy_CursorType)) == NULL) return NULL; +#if PY_VERSION_HEX < 0x03080000 + /* Workaround for Python issue 35810; no longer necessary in Python 3.8 */ + Py_INCREF(PLy_CursorType); +#endif cursor->portalname = NULL; cursor->closed = false; cursor->mcxt = AllocSetContextCreate(TopMemoryContext, @@ -177,8 +202,12 @@ PLy_cursor_plan(PyObject *ob, PyObject *args) return NULL; } - if ((cursor = PyObject_New(PLyCursorObject, &PLy_CursorType)) == NULL) + if ((cursor = PyObject_New(PLyCursorObject, PLy_CursorType)) == NULL) return NULL; +#if PY_VERSION_HEX < 0x03080000 + /* Workaround for Python issue 35810; no longer necessary in Python 3.8 */ + Py_INCREF(PLy_CursorType); +#endif cursor->portalname = NULL; cursor->closed = false; cursor->mcxt = AllocSetContextCreate(TopMemoryContext, @@ -272,30 +301,35 @@ PLy_cursor_plan(PyObject *ob, PyObject *args) } static void -PLy_cursor_dealloc(PyObject *arg) +PLy_cursor_dealloc(PLyCursorObject *self) { - PLyCursorObject *cursor; +#if PY_VERSION_HEX >= 0x03080000 + PyTypeObject *tp = Py_TYPE(self); +#endif Portal portal; - cursor = (PLyCursorObject *) arg; - - if (!cursor->closed) + if (!self->closed) { - portal = GetPortalByName(cursor->portalname); + portal = GetPortalByName(self->portalname); if (PortalIsValid(portal)) { UnpinPortal(portal); SPI_cursor_close(portal); } - cursor->closed = true; + self->closed = true; } - if (cursor->mcxt) + if (self->mcxt) { - MemoryContextDelete(cursor->mcxt); - cursor->mcxt = NULL; + MemoryContextDelete(self->mcxt); + self->mcxt = NULL; } - arg->ob_type->tp_free(arg); + + PyObject_Free(self); +#if PY_VERSION_HEX >= 0x03080000 + /* This was not needed before Python 3.8 (Python issue 35810) */ + Py_DECREF(tp); +#endif } static PyObject * diff --git a/src/pl/plpython/plpy_planobject.c b/src/pl/plpython/plpy_planobject.c index 9427674d2f4..3e385555e5e 100644 --- a/src/pl/plpython/plpy_planobject.c +++ b/src/pl/plpython/plpy_planobject.c @@ -12,7 +12,7 @@ #include "plpython.h" #include "utils/memutils.h" -static void PLy_plan_dealloc(PyObject *arg); +static void PLy_plan_dealloc(PLyPlanObject *self); static PyObject *PLy_plan_cursor(PyObject *self, PyObject *args); static PyObject *PLy_plan_execute(PyObject *self, PyObject *args); static PyObject *PLy_plan_status(PyObject *self, PyObject *args); @@ -26,20 +26,37 @@ static PyMethodDef PLy_plan_methods[] = { {NULL, NULL, 0, NULL} }; -static PyTypeObject PLy_PlanType = { - PyVarObject_HEAD_INIT(NULL, 0) - .tp_name = "PLyPlan", - .tp_basicsize = sizeof(PLyPlanObject), - .tp_dealloc = PLy_plan_dealloc, - .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, - .tp_doc = PLy_plan_doc, - .tp_methods = PLy_plan_methods, +static PyType_Slot PLyPlan_slots[] = +{ + { + Py_tp_dealloc, PLy_plan_dealloc + }, + { + Py_tp_doc, (char *) PLy_plan_doc + }, + { + Py_tp_methods, PLy_plan_methods + }, + { + 0, NULL + } }; +static PyType_Spec PLyPlan_spec = +{ + .name = "PLyPlan", + .basicsize = sizeof(PLyPlanObject), + .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, + .slots = PLyPlan_slots, +}; + +static PyTypeObject *PLy_PlanType; + void PLy_plan_init_type(void) { - if (PyType_Ready(&PLy_PlanType) < 0) + PLy_PlanType = (PyTypeObject *) PyType_FromSpec(&PLyPlan_spec); + if (!PLy_PlanType) elog(ERROR, "could not initialize PLy_PlanType"); } @@ -48,8 +65,12 @@ PLy_plan_new(void) { PLyPlanObject *ob; - if ((ob = PyObject_New(PLyPlanObject, &PLy_PlanType)) == NULL) + if ((ob = PyObject_New(PLyPlanObject, PLy_PlanType)) == NULL) return NULL; +#if PY_VERSION_HEX < 0x03080000 + /* Workaround for Python issue 35810; no longer necessary in Python 3.8 */ + Py_INCREF(PLy_PlanType); +#endif ob->plan = NULL; ob->nargs = 0; @@ -63,25 +84,32 @@ PLy_plan_new(void) bool is_PLyPlanObject(PyObject *ob) { - return ob->ob_type == &PLy_PlanType; + return ob->ob_type == PLy_PlanType; } static void -PLy_plan_dealloc(PyObject *arg) +PLy_plan_dealloc(PLyPlanObject *self) { - PLyPlanObject *ob = (PLyPlanObject *) arg; +#if PY_VERSION_HEX >= 0x03080000 + PyTypeObject *tp = Py_TYPE(self); +#endif - if (ob->plan) + if (self->plan) { - SPI_freeplan(ob->plan); - ob->plan = NULL; + SPI_freeplan(self->plan); + self->plan = NULL; } - if (ob->mcxt) + if (self->mcxt) { - MemoryContextDelete(ob->mcxt); - ob->mcxt = NULL; + MemoryContextDelete(self->mcxt); + self->mcxt = NULL; } - arg->ob_type->tp_free(arg); + + PyObject_Free(self); +#if PY_VERSION_HEX >= 0x03080000 + /* This was not needed before Python 3.8 (Python issue 35810) */ + Py_DECREF(tp); +#endif } diff --git a/src/pl/plpython/plpy_procedure.c b/src/pl/plpython/plpy_procedure.c index c35a3b801ab..b494eeb474f 100644 --- a/src/pl/plpython/plpy_procedure.c +++ b/src/pl/plpython/plpy_procedure.c @@ -350,6 +350,7 @@ PLy_procedure_compile(PLyProcedure *proc, const char *src) { PyObject *crv = NULL; char *msrc; + PyObject *code0; proc->globals = PyDict_Copy(PLy_interp_globals); @@ -368,7 +369,9 @@ PLy_procedure_compile(PLyProcedure *proc, const char *src) msrc = PLy_procedure_munge_source(proc->pyname, src); /* Save the mangled source for later inclusion in tracebacks */ proc->src = MemoryContextStrdup(proc->mcxt, msrc); - crv = PyRun_String(msrc, Py_file_input, proc->globals, NULL); + code0 = Py_CompileString(msrc, "", Py_file_input); + if (code0) + crv = PyEval_EvalCode(code0, proc->globals, NULL); pfree(msrc); if (crv != NULL) diff --git a/src/pl/plpython/plpy_resultobject.c b/src/pl/plpython/plpy_resultobject.c index 95acce65493..80fa1d7accc 100644 --- a/src/pl/plpython/plpy_resultobject.c +++ b/src/pl/plpython/plpy_resultobject.c @@ -10,7 +10,7 @@ #include "plpy_resultobject.h" #include "plpython.h" -static void PLy_result_dealloc(PyObject *arg); +static void PLy_result_dealloc(PLyResultObject *self); static PyObject *PLy_result_colnames(PyObject *self, PyObject *unused); static PyObject *PLy_result_coltypes(PyObject *self, PyObject *unused); static PyObject *PLy_result_coltypmods(PyObject *self, PyObject *unused); @@ -24,17 +24,6 @@ static int PLy_result_ass_subscript(PyObject *arg, PyObject *item, PyObject *val static char PLy_result_doc[] = "Results of a PostgreSQL query"; -static PySequenceMethods PLy_result_as_sequence = { - .sq_length = PLy_result_length, - .sq_item = PLy_result_item, -}; - -static PyMappingMethods PLy_result_as_mapping = { - .mp_length = PLy_result_length, - .mp_subscript = PLy_result_subscript, - .mp_ass_subscript = PLy_result_ass_subscript, -}; - static PyMethodDef PLy_result_methods[] = { {"colnames", PLy_result_colnames, METH_NOARGS, NULL}, {"coltypes", PLy_result_coltypes, METH_NOARGS, NULL}, @@ -44,23 +33,55 @@ static PyMethodDef PLy_result_methods[] = { {NULL, NULL, 0, NULL} }; -static PyTypeObject PLy_ResultType = { - PyVarObject_HEAD_INIT(NULL, 0) - .tp_name = "PLyResult", - .tp_basicsize = sizeof(PLyResultObject), - .tp_dealloc = PLy_result_dealloc, - .tp_as_sequence = &PLy_result_as_sequence, - .tp_as_mapping = &PLy_result_as_mapping, - .tp_str = &PLy_result_str, - .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, - .tp_doc = PLy_result_doc, - .tp_methods = PLy_result_methods, +static PyType_Slot PLyResult_slots[] = +{ + { + Py_tp_dealloc, PLy_result_dealloc + }, + { + Py_sq_length, PLy_result_length + }, + { + Py_sq_item, PLy_result_item + }, + { + Py_mp_length, PLy_result_length + }, + { + Py_mp_subscript, PLy_result_subscript + }, + { + Py_mp_ass_subscript, PLy_result_ass_subscript + }, + { + Py_tp_str, PLy_result_str + }, + { + Py_tp_doc, (char *) PLy_result_doc + }, + { + Py_tp_methods, PLy_result_methods + }, + { + 0, NULL + } +}; + +static PyType_Spec PLyResult_spec = +{ + .name = "PLyResult", + .basicsize = sizeof(PLyResultObject), + .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, + .slots = PLyResult_slots, }; +static PyTypeObject *PLy_ResultType; + void PLy_result_init_type(void) { - if (PyType_Ready(&PLy_ResultType) < 0) + PLy_ResultType = (PyTypeObject *) PyType_FromSpec(&PLyResult_spec); + if (!PLy_ResultType) elog(ERROR, "could not initialize PLy_ResultType"); } @@ -69,8 +90,12 @@ PLy_result_new(void) { PLyResultObject *ob; - if ((ob = PyObject_New(PLyResultObject, &PLy_ResultType)) == NULL) + if ((ob = PyObject_New(PLyResultObject, PLy_ResultType)) == NULL) return NULL; +#if PY_VERSION_HEX < 0x03080000 + /* Workaround for Python issue 35810; no longer necessary in Python 3.8 */ + Py_INCREF(PLy_ResultType); +#endif /* ob->tuples = NULL; */ @@ -89,20 +114,26 @@ PLy_result_new(void) } static void -PLy_result_dealloc(PyObject *arg) +PLy_result_dealloc(PLyResultObject *self) { - PLyResultObject *ob = (PLyResultObject *) arg; - - Py_XDECREF(ob->nrows); - Py_XDECREF(ob->rows); - Py_XDECREF(ob->status); - if (ob->tupdesc) +#if PY_VERSION_HEX >= 0x03080000 + PyTypeObject *tp = Py_TYPE(self); +#endif + + Py_XDECREF(self->nrows); + Py_XDECREF(self->rows); + Py_XDECREF(self->status); + if (self->tupdesc) { - FreeTupleDesc(ob->tupdesc); - ob->tupdesc = NULL; + FreeTupleDesc(self->tupdesc); + self->tupdesc = NULL; } - arg->ob_type->tp_free(arg); + PyObject_Free(self); +#if PY_VERSION_HEX >= 0x03080000 + /* This was not needed before Python 3.8 (Python issue 35810) */ + Py_DECREF(tp); +#endif } static PyObject * @@ -125,7 +156,7 @@ PLy_result_colnames(PyObject *self, PyObject *unused) { Form_pg_attribute attr = TupleDescAttr(ob->tupdesc, i); - PyList_SET_ITEM(list, i, PLyUnicode_FromString(NameStr(attr->attname))); + PyList_SetItem(list, i, PLyUnicode_FromString(NameStr(attr->attname))); } return list; @@ -151,7 +182,7 @@ PLy_result_coltypes(PyObject *self, PyObject *unused) { Form_pg_attribute attr = TupleDescAttr(ob->tupdesc, i); - PyList_SET_ITEM(list, i, PyLong_FromLong(attr->atttypid)); + PyList_SetItem(list, i, PyLong_FromLong(attr->atttypid)); } return list; @@ -177,7 +208,7 @@ PLy_result_coltypmods(PyObject *self, PyObject *unused) { Form_pg_attribute attr = TupleDescAttr(ob->tupdesc, i); - PyList_SET_ITEM(list, i, PyLong_FromLong(attr->atttypmod)); + PyList_SetItem(list, i, PyLong_FromLong(attr->atttypmod)); } return list; @@ -227,7 +258,7 @@ PLy_result_str(PyObject *arg) PLyResultObject *ob = (PLyResultObject *) arg; return PyUnicode_FromFormat("<%s status=%S nrows=%S rows=%S>", - Py_TYPE(ob)->tp_name, + "PLyResult", ob->status, ob->nrows, ob->rows); diff --git a/src/pl/plpython/plpy_subxactobject.c b/src/pl/plpython/plpy_subxactobject.c index 5c92a0e089a..ad24a9fc4b8 100644 --- a/src/pl/plpython/plpy_subxactobject.c +++ b/src/pl/plpython/plpy_subxactobject.c @@ -15,7 +15,6 @@ List *explicit_subtransactions = NIL; -static void PLy_subtransaction_dealloc(PyObject *subxact); static PyObject *PLy_subtransaction_enter(PyObject *self, PyObject *unused); static PyObject *PLy_subtransaction_exit(PyObject *self, PyObject *args); @@ -31,21 +30,35 @@ static PyMethodDef PLy_subtransaction_methods[] = { {NULL, NULL, 0, NULL} }; -static PyTypeObject PLy_SubtransactionType = { - PyVarObject_HEAD_INIT(NULL, 0) - .tp_name = "PLySubtransaction", - .tp_basicsize = sizeof(PLySubtransactionObject), - .tp_dealloc = PLy_subtransaction_dealloc, - .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, - .tp_doc = PLy_subtransaction_doc, - .tp_methods = PLy_subtransaction_methods, +static PyType_Slot PLySubtransaction_slots[] = +{ + { + Py_tp_doc, (char *) PLy_subtransaction_doc + }, + { + Py_tp_methods, PLy_subtransaction_methods + }, + { + 0, NULL + } }; +static PyType_Spec PLySubtransaction_spec = +{ + .name = "PLySubtransaction", + .basicsize = sizeof(PLySubtransactionObject), + .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, + .slots = PLySubtransaction_slots, +}; + +static PyTypeObject *PLy_SubtransactionType; + void PLy_subtransaction_init_type(void) { - if (PyType_Ready(&PLy_SubtransactionType) < 0) + PLy_SubtransactionType = (PyTypeObject *) PyType_FromSpec(&PLySubtransaction_spec); + if (!PLy_SubtransactionType) elog(ERROR, "could not initialize PLy_SubtransactionType"); } @@ -55,10 +68,13 @@ PLy_subtransaction_new(PyObject *self, PyObject *unused) { PLySubtransactionObject *ob; - ob = PyObject_New(PLySubtransactionObject, &PLy_SubtransactionType); - + ob = PyObject_New(PLySubtransactionObject, PLy_SubtransactionType); if (ob == NULL) return NULL; +#if PY_VERSION_HEX < 0x03080000 + /* Workaround for Python issue 35810; no longer necessary in Python 3.8 */ + Py_INCREF(PLy_SubtransactionType); +#endif ob->started = false; ob->exited = false; @@ -66,12 +82,6 @@ PLy_subtransaction_new(PyObject *self, PyObject *unused) return (PyObject *) ob; } -/* Python requires a dealloc function to be defined */ -static void -PLy_subtransaction_dealloc(PyObject *subxact) -{ -} - /* * subxact.__enter__() or subxact.enter() * diff --git a/src/pl/plpython/plpy_typeio.c b/src/pl/plpython/plpy_typeio.c index 51e1d610259..1d127ae3ffe 100644 --- a/src/pl/plpython/plpy_typeio.c +++ b/src/pl/plpython/plpy_typeio.c @@ -723,7 +723,7 @@ PLyList_FromArray_recurse(PLyDatumToOb *elm, int *dims, int ndim, int dim, sublist = PLyList_FromArray_recurse(elm, dims, ndim, dim + 1, dataptr_p, bitmap_p, bitmask_p); - PyList_SET_ITEM(list, i, sublist); + PyList_SetItem(list, i, sublist); } } else @@ -742,14 +742,14 @@ PLyList_FromArray_recurse(PLyDatumToOb *elm, int *dims, int ndim, int dim, if (bitmap && (*bitmap & bitmask) == 0) { Py_INCREF(Py_None); - PyList_SET_ITEM(list, i, Py_None); + PyList_SetItem(list, i, Py_None); } else { Datum itemvalue; itemvalue = fetch_att(dataptr, elm->typbyval, elm->typlen); - PyList_SET_ITEM(list, i, elm->func(elm, itemvalue)); + PyList_SetItem(list, i, elm->func(elm, itemvalue)); dataptr = att_addlength_pointer(dataptr, elm->typlen, dataptr); dataptr = (char *) att_align_nominal(dataptr, elm->typalign); } base-commit: ad40644eb8582fc1f537330b76ae7893cacf7b21 -- 2.48.1