bpo-35081: Add _PyThreadState_GET() internal macro (GH-10266)

If Py_BUILD_CORE is defined, the PyThreadState_GET() macro access
_PyRuntime which comes from the internal pycore_state.h header.
Public headers must not require internal headers.

Move PyThreadState_GET() and _PyInterpreterState_GET_UNSAFE() from
Include/pystate.h to Include/internal/pycore_state.h, and rename
PyThreadState_GET() to _PyThreadState_GET() there.

The PyThreadState_GET() macro of pystate.h is now redefined when
pycore_state.h is included, to use the fast _PyThreadState_GET().

Changes:

* Add _PyThreadState_GET() macro
* Replace "PyThreadState_GET()->interp" with
  _PyInterpreterState_GET_UNSAFE()
* Replace PyThreadState_GET() with _PyThreadState_GET() in internal C
  files (compiled with Py_BUILD_CORE defined), but keep
  PyThreadState_GET() in the public header files.
* _testcapimodule.c: replace PyThreadState_GET() with
  PyThreadState_Get(); the module is not compiled with Py_BUILD_CORE
  defined.
* pycore_state.h now requires Py_BUILD_CORE to be defined.

1 files changed, 4 insertions, 4 deletions

diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index d349aaf6dec..160f30ce6d6 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -530,7 +530,7 @@ _Py_InitializeCore_impl(PyInterpreterState **interp_p,
     /* bpo-34008: For backward compatibility reasons, calling Py_Main() after
        Py_Initialize() ignores the new configuration. */
     if (_PyRuntime.core_initialized) {
-        PyThreadState *tstate = PyThreadState_GET();
+        PyThreadState *tstate = _PyThreadState_GET();
         if (!tstate) {
             return _Py_INIT_ERR("failed to read thread state");
         }
@@ -1009,7 +1009,7 @@ Py_FinalizeEx(void)
     wait_for_thread_shutdown();
 
     /* Get current thread state and interpreter pointer */
-    tstate = PyThreadState_GET();
+    tstate = _PyThreadState_GET();
     interp = tstate->interp;
 
     /* The interpreter is still entirely intact at this point, and the
@@ -1406,7 +1406,7 @@ Py_EndInterpreter(PyThreadState *tstate)
 {
     PyInterpreterState *interp = tstate->interp;
 
-    if (tstate != PyThreadState_GET())
+    if (tstate != _PyThreadState_GET())
         Py_FatalError("Py_EndInterpreter: thread is not current");
     if (tstate->frame != NULL)
         Py_FatalError("Py_EndInterpreter: thread still has a frame");
@@ -1928,7 +1928,7 @@ fatal_error(const char *prefix, const char *msg, int status)
        and holds the GIL */
     PyThreadState *tss_tstate = PyGILState_GetThisThreadState();
     if (tss_tstate != NULL) {
-        PyThreadState *tstate = PyThreadState_GET();
+        PyThreadState *tstate = _PyThreadState_GET();
         if (tss_tstate != tstate) {
             /* The Python thread does not hold the GIL */
             tss_tstate = NULL;