BLD/WHL: declare Python 3 wheels as abi3-compliant (wait for #154 #156 and #157)

extension/wrapper.cpp

@@ -22,6 +22,9 @@ typedef struct {
     elsetrec satrec[0];
 } SatrecArrayObject;
 
+static PyObject* SatrecType = NULL;
+static PyObject* SatrecArrayType = NULL;
+
 /* Support routine that is used to support NumPy array broadcasting for
    both individual satellite objects and also arrays. */
 
@@ -121,7 +124,8 @@ Satrec_twoline2rv(PyTypeObject *cls, PyObject *args)
     line2[68] = '\0';
 
     /* Allocate the new object. */
-    SatrecObject *self = (SatrecObject*) cls->tp_alloc(cls, 0);
+    allocfunc alloc_func = (allocfunc)PyType_GetSlot(cls, Py_tp_alloc);
+    SatrecObject *self = (SatrecObject*)alloc_func(cls, 0);
     if (!self)
         return NULL;
 
@@ -424,7 +428,7 @@ get_intldesg(SatrecObject *self, void *closure)
 static int
 set_intldesg(SatrecObject *self, PyObject *value, void *closure)
 {
-    const char *s = PyUnicode_AsUTF8(value);
+    const char *s = PyUnicode_AsUTF8AndSize(value, NULL);
     if (!s)
         return -1;
     strncpy(self->satrec.intldesg, s, 10);
@@ -460,7 +464,7 @@ get_satnum_str(SatrecObject *self, void *closure)
 static int
 set_satnum_str(SatrecObject *self, PyObject *value, void *closure)
 {
-    const char *s = PyUnicode_AsUTF8(value);
+    const char *s = PyUnicode_AsUTF8AndSize(value, NULL);
     if (!s)
         return -1;
     strncpy(self->satrec.satnum, s, 5);
@@ -483,22 +487,13 @@ static PyGetSetDef Satrec_getset[] = {
     {NULL},
 };
 
-static PyTypeObject SatrecType = {
-    PyVarObject_HEAD_INIT(NULL, 0)
-    /* See the module initialization function at the bottom of this file. */
-};
-
 /* Details of the SatrecArray. */
 
 static Py_ssize_t
 Satrec_len(PyObject *self) {
     return ((SatrecArrayObject*)self)->ob_base.ob_size;
 }
 
-static PySequenceMethods SatrecArray_as_sequence = {
-    Satrec_len
-};
-
 static PyObject *
 SatrecArray_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 {
@@ -510,7 +505,9 @@ SatrecArray_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
     if (length == -1)
         return NULL;
 
-    return type->tp_alloc(type, length);
+    allocfunc alloc_func = (allocfunc)PyType_GetSlot(type, Py_tp_alloc);
+    PyObject *ret = alloc_func(type, length);
+    return ret;
 }
 
 
@@ -529,7 +526,7 @@ SatrecArray_init(SatrecArrayObject *self, PyObject *args, PyObject *kwds)
         PyObject *item = PySequence_GetItem(sequence, i);
         if (!item)
             return -1;
-        if (!PyObject_IsInstance(item, (PyObject*) &SatrecType)) {
+        if (!PyObject_IsInstance(item, (PyObject*) SatrecType)) {
             PyErr_Format(PyExc_ValueError, "every item must be a Satrec,"
                          " but element %d is: %R", i, item);
             Py_DECREF(item);
@@ -557,9 +554,40 @@ static PyMethodDef SatrecArray_methods[] = {
     {NULL, NULL}
 };
 
-static PyTypeObject SatrecArrayType = {
-    PyVarObject_HEAD_INIT(NULL, sizeof(elsetrec))
-    /* See the module initialization function at the bottom of this file. */
+static char doc_SatRecType[23] = "SGP4 satellite record.";
+static PyType_Slot SatrecType_slots[] = {
+    {Py_tp_doc, doc_SatRecType},
+    {Py_tp_methods, Satrec_methods},
+    {Py_tp_members, Satrec_members},
+    {Py_tp_getset, Satrec_getset},
+    {Py_tp_new, (void *)PyType_GenericNew},
+    {0, NULL},
+};
+
+static PyType_Spec SatrecType_spec = {
+    .name = "sgp4.vallado_cpp.Satrec",
+    .basicsize = sizeof(SatrecObject),
+    .itemsize = 0,
+    .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_IMMUTABLETYPE,
+    .slots = SatrecType_slots,
+};
+
+static char doc_SatRecArrayType[26] = "SGP4 array of satellites.";
+static PyType_Slot SatrecArrayType_slots[] = {
+    {Py_tp_doc, doc_SatRecArrayType},
+    {Py_tp_methods, SatrecArray_methods},
+    {Py_tp_init, (void *)SatrecArray_init},
+    {Py_tp_new, (void *)SatrecArray_new},
+    {Py_sq_length, (void *)Satrec_len},
+    {0, NULL},
+};
+
+static PyType_Spec SatrecArrayType_spec = {
+    .name = "sgp4.vallado_cpp.SatrecArray",
+    .basicsize = sizeof(SatrecArrayObject),
+    .itemsize = sizeof(elsetrec),
+    .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_IMMUTABLETYPE,
+    .slots = SatrecArrayType_slots,
 };
 
 /* The module that ties it all together. */
@@ -575,45 +603,25 @@ static PyModuleDef module = {
 PyMODINIT_FUNC
 PyInit_vallado_cpp(void)
 {
-    SatrecType.tp_name = "sgp4.vallado_cpp.Satrec";
-    SatrecType.tp_basicsize = sizeof(SatrecObject);
-    SatrecArrayType.tp_itemsize = 0;
-    SatrecType.tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE;
-    SatrecType.tp_doc = "SGP4 satellite record.";
-    SatrecType.tp_methods = Satrec_methods;
-    SatrecType.tp_members = Satrec_members;
-    SatrecType.tp_getset = Satrec_getset;
-    SatrecType.tp_new = PyType_GenericNew;
-
-    if (PyType_Ready(&SatrecType) < 0)
+    SatrecType = PyType_FromSpec(&SatrecType_spec);
+    if (SatrecType == NULL)
         return NULL;
 
-    SatrecArrayType.tp_name = "sgp4.vallado_cpp.SatrecArray";
-    SatrecArrayType.tp_basicsize = sizeof(SatrecArrayObject);
-    SatrecArrayType.tp_itemsize = sizeof(elsetrec);
-    SatrecArrayType.tp_as_sequence = &SatrecArray_as_sequence;
-    SatrecArrayType.tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE;
-    SatrecArrayType.tp_doc = "SGP4 array of satellites.";
-    SatrecArrayType.tp_methods = SatrecArray_methods;
-    SatrecArrayType.tp_init = (initproc) SatrecArray_init;
-    SatrecArrayType.tp_new = SatrecArray_new;
-
-    if (PyType_Ready(&SatrecArrayType) < 0)
+    SatrecArrayType = PyType_FromSpec(&SatrecArrayType_spec);
+    if (SatrecArrayType == NULL)
         return NULL;
 
     PyObject *m = PyModule_Create(&module);
     if (m == NULL)
         return NULL;
 
-    Py_INCREF(&SatrecType);
-    if (PyModule_AddObject(m, "Satrec", (PyObject *) &SatrecType) < 0) {
+    if (PyModule_AddObject(m, "Satrec", SatrecType) < 0) {
         Py_DECREF(&SatrecType);
         Py_DECREF(m);
         return NULL;
     }
 
-    Py_INCREF(&SatrecArrayType);
-    if (PyModule_AddObject(m, "SatrecArray", (PyObject *) &SatrecArrayType) < 0) {
+    if (PyModule_AddObject(m, "SatrecArray", SatrecArrayType) < 0) {
         Py_DECREF(&SatrecArrayType);
         Py_DECREF(&SatrecType);
         Py_DECREF(m);

setup.py

@@ -14,10 +14,26 @@
 
 import os
 import sys
+import sysconfig
+from distutils.ccompiler import get_default_compiler
 from distutils.core import setup, Extension
 
 PYTHON_SGP4_COMPILE = os.environ.get('PYTHON_SGP4_COMPILE', '')
+
+USE_PY_LIMITED_API = (
+    # Py_buffer is required
+    sys.version_info >= (3, 11)
+    # LIMITED_API is not compatible with free-threading (as of CPython 3.14)
+    and not sysconfig.get_config_var("Py_GIL_DISABLED")
+)
+ABI3_TARGET_VERSION = "".join(str(_) for _ in sys.version_info[:2])
+ABI3_TARGET_HEX = hex(sys.hexversion & 0xFFFF00F0)
+
 ext_modules = []
+define_macros = []
+
+if USE_PY_LIMITED_API:
+    define_macros.append(("Py_LIMITED_API", ABI3_TARGET_HEX))
 
 if sys.version_info[0] == 3 and PYTHON_SGP4_COMPILE != 'never':
 
@@ -33,13 +49,18 @@
             'extension/SGP4.cpp',
             'extension/wrapper.cpp',
         ],
+        define_macros=define_macros,
+        py_limited_api=USE_PY_LIMITED_API,
 
         # TODO: can we safely figure out how to use a pair of options
         # like these, adapted to as many platforms as possible, to use
         # multiple processors when available?
         # extra_compile_args=['-fopenmp'],
         # extra_link_args=['-fopenmp'],
-        extra_compile_args=['-ffloat-store'],
+        extra_compile_args=[
+            '-ffloat-store',
+            "-std=c++20" if get_default_compiler() != "msvc" else "/std:c++20",
+        ],
     ))
 
 # Read the package's docstring and "__version__" without importing it.
@@ -89,4 +110,7 @@
     package_data = {'sgp4': ['SGP4-VER.TLE', 'sample*', 'tcppver.out']},
     provides = ['sgp4'],
     ext_modules = ext_modules,
+    options={
+        "bdist_wheel": {"py_limited_api": "cp%s" % ABI3_TARGET_VERSION}
+    } if USE_PY_LIMITED_API else {},
 )