py_panda: Remove panda-specific MAIN_DIR init code

Author: rdb

src/interrogatedb/py_panda.cxx

@@ -5,7 +5,6 @@
  */
 
 #include "py_panda.h"
-#include "executionEnvironment.h"
 
 #ifdef HAVE_PYTHON
 
@@ -696,66 +695,6 @@ PyObject *Dtool_PyModuleInitHelper(const LibraryDef *defs[], const char *modulen
 #endif
   }
 
-  // MAIN_DIR needs to be set very early; this seems like a convenient place
-  // to do that.  Perhaps we'll find a better place for this in the future.
-  static bool initialized_main_dir = false;
-  if (!initialized_main_dir) {
-    /*if (interrogatedb_cat.is_debug()) {
-      // Good opportunity to print this out once, at startup.
-      interrogatedb_cat.debug()
-        << "Python " << version << "\n";
-    }*/
-
-    if (!ExecutionEnvironment::has_environment_variable("MAIN_DIR")) {
-      // Grab the __main__ module.
-      PyObject *main_module = PyImport_ImportModule("__main__");
-      if (main_module == NULL) {
-        std::cerr << "Warning: unable to import __main__\n";
-      }
-
-      // Extract the __file__ attribute, if present.
-      Filename main_dir;
-      PyObject *file_attr = nullptr;
-      if (main_module != nullptr) {
-        file_attr = PyObject_GetAttrString(main_module, "__file__");
-      }
-      if (file_attr == nullptr) {
-        // Must be running in the interactive interpreter.  Use the CWD.
-        main_dir = ExecutionEnvironment::get_cwd();
-      } else {
-#if PY_MAJOR_VERSION >= 3
-        Py_ssize_t length;
-        wchar_t *buffer = PyUnicode_AsWideCharString(file_attr, &length);
-        if (buffer != nullptr) {
-          main_dir = Filename::from_os_specific_w(std::wstring(buffer, length));
-          main_dir.make_absolute();
-          main_dir = main_dir.get_dirname();
-          PyMem_Free(buffer);
-        }
-#else
-        char *buffer;
-        Py_ssize_t length;
-        if (PyString_AsStringAndSize(file_attr, &buffer, &length) != -1) {
-          main_dir = Filename::from_os_specific(std::string(buffer, length));
-          main_dir.make_absolute();
-          main_dir = main_dir.get_dirname();
-        }
-#endif
-        else {
-          std::cerr << "Invalid string for __main__.__file__\n";
-        }
-      }
-      ExecutionEnvironment::shadow_environment_variable("MAIN_DIR", main_dir.to_os_specific());
-      PyErr_Clear();
-    }
-    initialized_main_dir = true;
-
-    // Also, while we are at it, initialize the thread swap hook.
-#if defined(HAVE_THREADS) && defined(SIMPLE_THREADS)
-    global_thread_state_swap = PyThreadState_Swap;
-#endif
-  }
-
   PyModule_AddIntConstant(module, "Dtool_PyNativeInterface", 1);
   return module;
 }