bpo-32030: Add _PyMainInterpreterConfig.executable (#4876)

* Add new fields to _PyMainInterpreterConfig:

  * executable
  * prefix
  * base_prefix
  * exec_prefix
  * base_exec_prefix

* _PySys_EndInit() now sets sys attributes from
  _PyMainInterpreterConfig

2 files changed, 32 insertions, 43 deletions

diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index 830f89d..8c62607 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -830,28 +830,7 @@ _Py_InitializeMainInterpreter(const _PyMainInterpreterConfig *config)
         return _Py_INIT_ERR("can't initialize time");
     }
 
-    /* Set sys attributes */
-    assert(interp->config.module_search_path != NULL);
-    if (PySys_SetObject("path", interp->config.module_search_path) != 0) {
-        return _Py_INIT_ERR("can't assign sys.path");
-    }
-    if (interp->config.argv != NULL) {
-        if (PySys_SetObject("argv", interp->config.argv) != 0) {
-            return _Py_INIT_ERR("can't assign sys.argv");
-        }
-    }
-    if (interp->config.warnoptions != NULL) {
-        if (PySys_SetObject("warnoptions", interp->config.warnoptions)) {
-            return _Py_INIT_ERR("can't assign sys.warnoptions");
-        }
-    }
-    if (interp->config.xoptions != NULL) {
-        if (PySys_SetObject("_xoptions", interp->config.xoptions)) {
-            return _Py_INIT_ERR("can't assign sys._xoptions");
-        }
-    }
-
-    if (_PySys_EndInit(interp->sysdict) < 0) {
+    if (_PySys_EndInit(interp->sysdict, &interp->config) < 0) {
         return _Py_INIT_ERR("can't finish initializing sys");
     }
 
@@ -1314,12 +1293,6 @@ new_interpreter(PyThreadState **tstate_p)
         return _Py_INIT_ERR("failed to copy main interpreter config");
     }
 
-    err = _PyPathConfig_Init(&interp->core_config);
-    if (_Py_INIT_FAILED(err)) {
-        return err;
-    }
-    wchar_t *sys_path = Py_GetPath();
-
     /* XXX The following is lax in error checking */
     PyObject *modules = PyDict_New();
     if (modules == NULL) {
@@ -1334,8 +1307,7 @@ new_interpreter(PyThreadState **tstate_p)
             goto handle_error;
         Py_INCREF(interp->sysdict);
         PyDict_SetItemString(interp->sysdict, "modules", modules);
-        PySys_SetPath(sys_path);
-        _PySys_EndInit(interp->sysdict);
+        _PySys_EndInit(interp->sysdict, &interp->config);
     }
 
     bimod = _PyImport_FindBuiltin("builtins", modules);
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index b33a316..24098b9 100644
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -2212,7 +2212,6 @@ err_occurred:
 }
 
 #undef SET_SYS_FROM_STRING
-#undef SET_SYS_FROM_STRING_BORROW
 
 /* Updating the sys namespace, returning integer error codes */
 #define SET_SYS_FROM_STRING_INT_RESULT(key, value)         \
@@ -2228,10 +2227,35 @@ err_occurred:
     } while (0)
 
 int
-_PySys_EndInit(PyObject *sysdict)
+_PySys_EndInit(PyObject *sysdict, _PyMainInterpreterConfig *config)
 {
     int res;
 
+    /* _PyMainInterpreterConfig_Read() must set all these variables */
+    assert(config->module_search_path != NULL);
+    assert(config->executable != NULL);
+    assert(config->prefix != NULL);
+    assert(config->base_prefix != NULL);
+    assert(config->exec_prefix != NULL);
+    assert(config->base_exec_prefix != NULL);
+
+    SET_SYS_FROM_STRING_BORROW("path", config->module_search_path);
+    SET_SYS_FROM_STRING_BORROW("executable", config->executable);
+    SET_SYS_FROM_STRING_BORROW("prefix", config->prefix);
+    SET_SYS_FROM_STRING_BORROW("base_prefix", config->base_prefix);
+    SET_SYS_FROM_STRING_BORROW("exec_prefix", config->exec_prefix);
+    SET_SYS_FROM_STRING_BORROW("base_exec_prefix", config->base_exec_prefix);
+
+    if (config->argv != NULL) {
+        SET_SYS_FROM_STRING_BORROW("argv", config->argv);
+    }
+    if (config->warnoptions != NULL) {
+        SET_SYS_FROM_STRING_BORROW("warnoptions", config->warnoptions);
+    }
+    if (config->xoptions != NULL) {
+        SET_SYS_FROM_STRING_BORROW("_xoptions", config->xoptions);
+    }
+
     /* Set flags to their final values */
     SET_SYS_FROM_STRING_INT_RESULT("flags", make_flags());
     /* prevent user from creating new instances */
@@ -2247,17 +2271,6 @@ _PySys_EndInit(PyObject *sysdict)
 
     SET_SYS_FROM_STRING_INT_RESULT("dont_write_bytecode",
                          PyBool_FromLong(Py_DontWriteBytecodeFlag));
-    SET_SYS_FROM_STRING_INT_RESULT("executable",
-                        PyUnicode_FromWideChar(
-                               Py_GetProgramFullPath(), -1));
-    SET_SYS_FROM_STRING_INT_RESULT("prefix",
-                        PyUnicode_FromWideChar(Py_GetPrefix(), -1));
-    SET_SYS_FROM_STRING_INT_RESULT("exec_prefix",
-                        PyUnicode_FromWideChar(Py_GetExecPrefix(), -1));
-    SET_SYS_FROM_STRING_INT_RESULT("base_prefix",
-                        PyUnicode_FromWideChar(Py_GetPrefix(), -1));
-    SET_SYS_FROM_STRING_INT_RESULT("base_exec_prefix",
-                        PyUnicode_FromWideChar(Py_GetExecPrefix(), -1));
 
     if (get_warnoptions() == NULL)
         return -1;
@@ -2268,8 +2281,12 @@ _PySys_EndInit(PyObject *sysdict)
     if (PyErr_Occurred())
         return -1;
     return 0;
+
+err_occurred:
+    return -1;
 }
 
+#undef SET_SYS_FROM_STRING_BORROW
 #undef SET_SYS_FROM_STRING_INT_RESULT
 
 static PyObject *