fix: Make org.jpy.PyLib.getCurrentLocals/Globals work for Python 3.13 (…

…#164)

* Made getCurrentLocals/Globals work in py3.13

* Make getting globals/locals thread safe

* Add JPy_XINCREF and use it

src/main/c/jni/org_jpy_PyLib.c

@@ -521,6 +521,7 @@ PyObject *getMainGlobals() {
  }
 
  pyGlobals = PyModule_GetDict(pyMainModule); // borrowed ref
+ JPy_INCREF(pyGlobals);
 
  return pyGlobals;
 }
@@ -532,7 +533,7 @@ JNIEXPORT jobject JNICALL Java_org_jpy_PyLib_getMainGlobals
 
  JPy_BEGIN_GIL_STATE
 
- globals = getMainGlobals(); // borrowed ref
+ globals = getMainGlobals(); // new ref
  if (globals == NULL) {
  goto error;
  }
@@ -543,6 +544,7 @@ JNIEXPORT jobject JNICALL Java_org_jpy_PyLib_getMainGlobals
  }
 
 error:
+ JPy_XDECREF(globals);
  JPy_END_GIL_STATE
 
  return objectRef;
@@ -555,7 +557,13 @@ JNIEXPORT jobject JNICALL Java_org_jpy_PyLib_getCurrentGlobals
 
  JPy_BEGIN_GIL_STATE
 
+#if PY_MAJOR_VERSION == 3 && PY_MINOR_VERSION <= 12
  globals = PyEval_GetGlobals(); // borrowed ref
+ JPy_XINCREF(globals);
+#else
+ // See https://peps.python.org/pep-0667 for the change in Python 3.13
+ globals = PyEval_GetFrameGlobals(); // new ref
+#endif
 
  if (globals == NULL) {
  goto error;
@@ -567,6 +575,7 @@ JNIEXPORT jobject JNICALL Java_org_jpy_PyLib_getCurrentGlobals
  }
 
 error:
+ JPy_XDECREF(globals);
  JPy_END_GIL_STATE
 
  return objectRef;
@@ -579,7 +588,14 @@ JNIEXPORT jobject JNICALL Java_org_jpy_PyLib_getCurrentLocals
 
  JPy_BEGIN_GIL_STATE
 
+#if PY_MAJOR_VERSION == 3 && PY_MINOR_VERSION <= 12
  locals = PyEval_GetLocals(); // borrowed ref
+ JPy_XINCREF(locals);
+#else
+ // See https://peps.python.org/pep-0667 for the change in Python 3.13
+ locals = PyEval_GetFrameLocals(); // new ref
+#endif
+
  if (locals == NULL) {
  goto error;
  }
@@ -590,6 +606,7 @@ JNIEXPORT jobject JNICALL Java_org_jpy_PyLib_getCurrentLocals
  }
 
 error:
+ JPy_XDECREF(locals);
  JPy_END_GIL_STATE
 
  return objectRef;
@@ -904,7 +921,8 @@ jlong executeInternal(JNIEnv* jenv, jclass jLibClass, jint jStart, jobject jGlob
 
  if (jGlobals == NULL) {
  JPy_DIAG_PRINT(JPy_DIAG_F_EXEC, "Java_org_jpy_PyLib_executeInternal: using main globals\n");
- pyGlobals = getMainGlobals();
+ pyGlobals = getMainGlobals(); // new ref
+ decGlobals = JNI_TRUE;
  if (pyGlobals == NULL) {
  PyLib_HandlePythonException(jenv);
  goto error;

src/main/c/jpy_module.h

@@ -33,6 +33,7 @@ extern "C" {
 #if 1
 #define JPy_DECREF(x) Py_DECREF(x)
 #define JPy_INCREF(x) Py_INCREF(x)
+#define JPy_XINCREF(x) Py_XINCREF(x)
 #define JPy_XDECREF(x) Py_XDECREF(x)
 #else
 #include "jpy_diag.h"