[3.6] bpo-29723: Consistently configure sys.path[0] (#636)
Directory and zipfile execution previously added
the parent directory of the directory or zipfile
as sys.path[0] and then subsequently overwrote
it with the directory or zipfile itself.
This caused problems in isolated mode, as it
overwrote the "stdlib as a zip archive" entry
in sys.path, as the parent directory was
never added.
The attempted fix to that issue in bpo-29319
created the opposite problem in *non*-isolated
mode, by potentially leaving the parent
directory on sys.path instead of overwriting it.
This change fixes the root cause of the problem
by removing the whole "add-and-overwrite" dance
for sys.path[0], and instead simply never adds
the parent directory to sys.path in the first
place.
(cherry picked from commit d2977a3ae2cc6802921b1e3b6e9d13fcfbda872d)
(cherry picked from commit c60948464fb0ec116ea227f6bce8a4bb8fb75257)
diff --git a/Modules/main.c b/Modules/main.c
index 2e6a60b..dd50211 100644
--- a/Modules/main.c
+++ b/Modules/main.c
@@ -225,55 +225,60 @@
return 0;
}
-static int
-RunMainFromImporter(wchar_t *filename)
+static PyObject *
+AsImportPathEntry(wchar_t *filename)
{
- PyObject *argv0 = NULL, *importer, *sys_path, *sys_path0;
- int sts;
+ PyObject *sys_path0 = NULL, *importer;
- argv0 = PyUnicode_FromWideChar(filename, wcslen(filename));
- if (argv0 == NULL)
+ sys_path0 = PyUnicode_FromWideChar(filename, wcslen(filename));
+ if (sys_path0 == NULL)
goto error;
- importer = PyImport_GetImporter(argv0);
+ importer = PyImport_GetImporter(sys_path0);
if (importer == NULL)
goto error;
if (importer == Py_None) {
- Py_DECREF(argv0);
+ Py_DECREF(sys_path0);
Py_DECREF(importer);
- return -1;
+ return NULL;
}
Py_DECREF(importer);
+ return sys_path0;
- /* argv0 is usable as an import source, so put it in sys.path[0]
- and import __main__ */
+error:
+ Py_XDECREF(sys_path0);
+ PySys_WriteStderr("Failed checking if argv[0] is an import path entry\n");
+ PyErr_Print();
+ PyErr_Clear();
+ return NULL;
+}
+
+
+static int
+RunMainFromImporter(PyObject *sys_path0)
+{
+ PyObject *sys_path;
+ int sts;
+
+ /* Assume sys_path0 has already been checked by AsImportPathEntry,
+ * so put it in sys.path[0] and import __main__ */
sys_path = PySys_GetObject("path");
if (sys_path == NULL) {
PyErr_SetString(PyExc_RuntimeError, "unable to get sys.path");
goto error;
}
- sys_path0 = PyList_GetItem(sys_path, 0);
- sts = 0;
- if (!sys_path0) {
- PyErr_Clear();
- sts = PyList_Append(sys_path, argv0);
- } else if (PyObject_IsTrue(sys_path0)) {
- sts = PyList_Insert(sys_path, 0, argv0);
- } else {
- sts = PyList_SetItem(sys_path, 0, argv0);
- }
+ sts = PyList_Insert(sys_path, 0, sys_path0);
if (sts) {
- argv0 = NULL;
+ sys_path0 = NULL;
goto error;
}
- Py_INCREF(argv0);
sts = RunModule(L"__main__", 0);
return sts != 0;
error:
- Py_XDECREF(argv0);
+ Py_XDECREF(sys_path0);
PyErr_Print();
return 1;
}
@@ -358,6 +363,7 @@
int saw_unbuffered_flag = 0;
char *opt;
PyCompilerFlags cf;
+ PyObject *main_importer_path = NULL;
PyObject *warning_option = NULL;
PyObject *warning_options = NULL;
@@ -714,7 +720,17 @@
argv[_PyOS_optind] = L"-m";
}
- PySys_SetArgv(argc-_PyOS_optind, argv+_PyOS_optind);
+ if (filename != NULL) {
+ main_importer_path = AsImportPathEntry(filename);
+ }
+
+ if (main_importer_path != NULL) {
+ /* Let RunMainFromImporter adjust sys.path[0] later */
+ PySys_SetArgvEx(argc-_PyOS_optind, argv+_PyOS_optind, 0);
+ } else {
+ /* Use config settings to decide whether or not to update sys.path[0] */
+ PySys_SetArgv(argc-_PyOS_optind, argv+_PyOS_optind);
+ }
if ((Py_InspectFlag || (command == NULL && filename == NULL && module == NULL)) &&
isatty(fileno(stdin)) &&
@@ -744,11 +760,11 @@
sts = -1; /* keep track of whether we've already run __main__ */
- if (filename != NULL) {
- sts = RunMainFromImporter(filename);
+ if (main_importer_path != NULL) {
+ sts = RunMainFromImporter(main_importer_path);
}
- if (sts==-1 && filename!=NULL) {
+ if (sts==-1 && filename != NULL) {
fp = _Py_wfopen(filename, L"r");
if (fp == NULL) {
char *cfilename_buffer;