gh-126220: Adapt _lsprof to Argument Clinic

Lib/test/test_cprofile.py

@@ -30,6 +30,22 @@ def test_bad_counter_during_dealloc(self):
 
             self.assertEqual(cm.unraisable.exc_type, TypeError)
 
+    def test_crash_on_no_args(self):
+        # gh-126220
+        import _lsprof
+
+        for profile in [_lsprof.Profiler(), cProfile.Profile()]:
+            for method in [
+                "_pystart_callback",
+                "_pyreturn_callback",
+                "_ccall_callback",
+                "_creturn_callback",
+            ]:
+                with self.subTest(profile=profile, method=method):
+                    method_obj = getattr(profile, method)
+                    with self.assertRaises(TypeError):
+                        method_obj()  # should not crash
+
     def test_evil_external_timer(self):
         # gh-120289
         # Disabling profiler in external timer should not crash

Misc/NEWS.d/next/Library/2024-10-31-14-06-28.gh-issue-126220.uJAJCU.rst

@@ -0,0 +1,2 @@
+Fix crash of ``cProfile.Profile`` and ``_lsprof.Profiler`` when their
+callbacks were directly called with 0 arguments.

Modules/_lsprof.c

@@ -606,17 +606,42 @@ setBuiltins(ProfilerObject *pObj, int nvalue)
     return 0;
 }
 
-PyObject* pystart_callback(ProfilerObject* self, PyObject *const *args, Py_ssize_t size)
+/*[clinic input]
+_lsprof.Profiler._pystart_callback
+
+    code: object
+    instruction_offset: object
+    /
+
+[clinic start generated code]*/
+
+static PyObject *
+_lsprof_Profiler__pystart_callback_impl(ProfilerObject *self, PyObject *code,
+                                        PyObject *instruction_offset)
+/*[clinic end generated code: output=5fec8b7ad5ed25e8 input=b166e6953c579cda]*/
 {
-    PyObject* code = args[0];
-    ptrace_enter_call((PyObject*)self, (void *)code, (PyObject *)code);
+    ptrace_enter_call((PyObject*)self, (void *)code, code);
 
     Py_RETURN_NONE;
 }
 
-PyObject* pyreturn_callback(ProfilerObject* self, PyObject *const *args, Py_ssize_t size)
+/*[clinic input]
+_lsprof.Profiler._pyreturn_callback
+
+    code: object
+    instruction_offset: object
+    retval: object
+    /
+
+[clinic start generated code]*/
+
+static PyObject *
+_lsprof_Profiler__pyreturn_callback_impl(ProfilerObject *self,
+                                         PyObject *code,
+                                         PyObject *instruction_offset,
+                                         PyObject *retval)
+/*[clinic end generated code: output=9e2f6fc1b882c51e input=667ffaeb2fa6fd1f]*/
 {
-    PyObject* code = args[0];
     ptrace_leave_call((PyObject*)self, (void *)code);
 
     Py_RETURN_NONE;
@@ -649,12 +674,24 @@ PyObject* get_cfunc_from_callable(PyObject* callable, PyObject* self_arg, PyObje
     return NULL;
 }
 
-PyObject* ccall_callback(ProfilerObject* self, PyObject *const *args, Py_ssize_t size)
+/*[clinic input]
+_lsprof.Profiler._ccall_callback
+
+    code: object
+    instruction_offset: object
+    callable: object
+    self_arg: object
+    /
+
+[clinic start generated code]*/
+
+static PyObject *
+_lsprof_Profiler__ccall_callback_impl(ProfilerObject *self, PyObject *code,
+                                      PyObject *instruction_offset,
+                                      PyObject *callable, PyObject *self_arg)
+/*[clinic end generated code: output=152db83cabd18cad input=0e66687cfb95c001]*/
 {
     if (self->flags & POF_BUILTINS) {
-        PyObject* callable = args[2];
-        PyObject* self_arg = args[3];
-
         PyObject* cfunc = get_cfunc_from_callable(callable, self_arg, self->missing);
 
         if (cfunc) {
@@ -667,12 +704,25 @@ PyObject* ccall_callback(ProfilerObject* self, PyObject *const *args, Py_ssize_t
     Py_RETURN_NONE;
 }
 
-PyObject* creturn_callback(ProfilerObject* self, PyObject *const *args, Py_ssize_t size)
+/*[clinic input]
+_lsprof.Profiler._creturn_callback
+
+    code: object
+    instruction_offset: object
+    callable: object
+    self_arg: object
+    /
+
+[clinic start generated code]*/
+
+static PyObject *
+_lsprof_Profiler__creturn_callback_impl(ProfilerObject *self, PyObject *code,
+                                        PyObject *instruction_offset,
+                                        PyObject *callable,
+                                        PyObject *self_arg)
+/*[clinic end generated code: output=1e886dde8fed8fb0 input=b18afe023746923a]*/
 {
     if (self->flags & POF_BUILTINS) {
-        PyObject* callable = args[2];
-        PyObject* self_arg = args[3];
-
         PyObject* cfunc = get_cfunc_from_callable(callable, self_arg, self->missing);
 
         if (cfunc) {
@@ -783,7 +833,7 @@ Stop collecting profiling information.\n\
 ");
 
 static PyObject*
-profiler_disable(ProfilerObject *self, PyObject* noarg)
+profiler_disable(ProfilerObject *self, PyObject* Py_UNUSED(unused))
 {
     if (self->flags & POF_EXT_TIMER) {
         PyErr_SetString(PyExc_RuntimeError,
@@ -921,14 +971,10 @@ static PyMethodDef profiler_methods[] = {
                     METH_NOARGS,                        disable_doc},
     {"clear",              (PyCFunction)profiler_clear,
                     METH_NOARGS,                        clear_doc},
-    {"_pystart_callback",  _PyCFunction_CAST(pystart_callback),
-                    METH_FASTCALL,                       NULL},
-    {"_pyreturn_callback", _PyCFunction_CAST(pyreturn_callback),
-                    METH_FASTCALL,                       NULL},
-    {"_ccall_callback",    _PyCFunction_CAST(ccall_callback),
-                    METH_FASTCALL,                       NULL},
-    {"_creturn_callback", _PyCFunction_CAST(creturn_callback),
-                    METH_FASTCALL,                       NULL},
+    _LSPROF_PROFILER__PYSTART_CALLBACK_METHODDEF
+    _LSPROF_PROFILER__PYRETURN_CALLBACK_METHODDEF
+    _LSPROF_PROFILER__CCALL_CALLBACK_METHODDEF
+    _LSPROF_PROFILER__CRETURN_CALLBACK_METHODDEF
     {NULL, NULL}
 };