mirror of
https://github.com/python/cpython.git
synced 2025-08-04 00:48:58 +00:00
bpo-42208: Move _PyImport_Cleanup() to pylifecycle.c (GH-23040)
Move _PyImport_Cleanup() to pylifecycle.c, rename it to finalize_modules(), split it (200 lines) into many smaller sub-functions and cleanup the code.
This commit is contained in:
Victor Stinner
GitHub
parent
8b3414818f
commit
dff1ad5090
2 changed files with 290 additions and 230 deletions
|
|
@ -8,7 +8,6 @@
|
|||
#include "pycore_ceval.h" // _PyEval_FiniGIL()
|
||||
#include "pycore_context.h" // _PyContext_Init()
|
||||
#include "pycore_fileutils.h" // _Py_ResetForceASCII()
|
||||
#include "pycore_import.h" // _PyImport_Cleanup()
|
||||
#include "pycore_initconfig.h" // _PyStatus_OK()
|
||||
#include "pycore_object.h" // _PyDebug_PrintTotalRefs()
|
||||
#include "pycore_pathconfig.h" // _PyConfig_WritePathConfig()
|
||||
|
|
@ -1192,6 +1191,292 @@ Py_Initialize(void)
|
|||
}
|
||||
|
||||
|
||||
static void
|
||||
finalize_modules_delete_special(PyThreadState *tstate, int verbose)
|
||||
{
|
||||
// List of names to clear in sys
|
||||
static const char * const sys_deletes[] = {
|
||||
"path", "argv", "ps1", "ps2",
|
||||
"last_type", "last_value", "last_traceback",
|
||||
"path_hooks", "path_importer_cache", "meta_path",
|
||||
"__interactivehook__",
|
||||
NULL
|
||||
};
|
||||
|
||||
static const char * const sys_files[] = {
|
||||
"stdin", "__stdin__",
|
||||
"stdout", "__stdout__",
|
||||
"stderr", "__stderr__",
|
||||
NULL
|
||||
};
|
||||
|
||||
PyInterpreterState *interp = tstate->interp;
|
||||
if (verbose) {
|
||||
PySys_WriteStderr("# clear builtins._\n");
|
||||
}
|
||||
if (PyDict_SetItemString(interp->builtins, "_", Py_None) < 0) {
|
||||
PyErr_WriteUnraisable(NULL);
|
||||
}
|
||||
|
||||
const char * const *p;
|
||||
for (p = sys_deletes; *p != NULL; p++) {
|
||||
if (verbose) {
|
||||
PySys_WriteStderr("# clear sys.%s\n", *p);
|
||||
}
|
||||
if (PyDict_SetItemString(interp->sysdict, *p, Py_None) < 0) {
|
||||
PyErr_WriteUnraisable(NULL);
|
||||
}
|
||||
}
|
||||
for (p = sys_files; *p != NULL; p+=2) {
|
||||
const char *name = p[0];
|
||||
const char *orig_name = p[1];
|
||||
if (verbose) {
|
||||
PySys_WriteStderr("# restore sys.%s\n", name);
|
||||
}
|
||||
PyObject *value = _PyDict_GetItemStringWithError(interp->sysdict,
|
||||
orig_name);
|
||||
if (value == NULL) {
|
||||
if (_PyErr_Occurred(tstate)) {
|
||||
PyErr_WriteUnraisable(NULL);
|
||||
}
|
||||
value = Py_None;
|
||||
}
|
||||
if (PyDict_SetItemString(interp->sysdict, name, value) < 0) {
|
||||
PyErr_WriteUnraisable(NULL);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
static PyObject*
|
||||
finalize_remove_modules(PyObject *modules, int verbose)
|
||||
{
|
||||
PyObject *weaklist = PyList_New(0);
|
||||
if (weaklist == NULL) {
|
||||
PyErr_WriteUnraisable(NULL);
|
||||
}
|
||||
|
||||
#define STORE_MODULE_WEAKREF(name, mod) \
|
||||
if (weaklist != NULL) { \
|
||||
PyObject *wr = PyWeakref_NewRef(mod, NULL); \
|
||||
if (wr) { \
|
||||
PyObject *tup = PyTuple_Pack(2, name, wr); \
|
||||
if (!tup || PyList_Append(weaklist, tup) < 0) { \
|
||||
PyErr_WriteUnraisable(NULL); \
|
||||
} \
|
||||
Py_XDECREF(tup); \
|
||||
Py_DECREF(wr); \
|
||||
} \
|
||||
else { \
|
||||
PyErr_WriteUnraisable(NULL); \
|
||||
} \
|
||||
}
|
||||
|
||||
#define CLEAR_MODULE(name, mod) \
|
||||
if (PyModule_Check(mod)) { \
|
||||
if (verbose && PyUnicode_Check(name)) { \
|
||||
PySys_FormatStderr("# cleanup[2] removing %U\n", name); \
|
||||
} \
|
||||
STORE_MODULE_WEAKREF(name, mod); \
|
||||
if (PyObject_SetItem(modules, name, Py_None) < 0) { \
|
||||
PyErr_WriteUnraisable(NULL); \
|
||||
} \
|
||||
}
|
||||
|
||||
if (PyDict_CheckExact(modules)) {
|
||||
Py_ssize_t pos = 0;
|
||||
PyObject *key, *value;
|
||||
while (PyDict_Next(modules, &pos, &key, &value)) {
|
||||
CLEAR_MODULE(key, value);
|
||||
}
|
||||
}
|
||||
else {
|
||||
PyObject *iterator = PyObject_GetIter(modules);
|
||||
if (iterator == NULL) {
|
||||
PyErr_WriteUnraisable(NULL);
|
||||
}
|
||||
else {
|
||||
PyObject *key;
|
||||
while ((key = PyIter_Next(iterator))) {
|
||||
PyObject *value = PyObject_GetItem(modules, key);
|
||||
if (value == NULL) {
|
||||
PyErr_WriteUnraisable(NULL);
|
||||
continue;
|
||||
}
|
||||
CLEAR_MODULE(key, value);
|
||||
Py_DECREF(value);
|
||||
Py_DECREF(key);
|
||||
}
|
||||
if (PyErr_Occurred()) {
|
||||
PyErr_WriteUnraisable(NULL);
|
||||
}
|
||||
Py_DECREF(iterator);
|
||||
}
|
||||
}
|
||||
#undef CLEAR_MODULE
|
||||
#undef STORE_MODULE_WEAKREF
|
||||
|
||||
return weaklist;
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
finalize_clear_modules_dict(PyObject *modules)
|
||||
{
|
||||
if (PyDict_CheckExact(modules)) {
|
||||
PyDict_Clear(modules);
|
||||
}
|
||||
else {
|
||||
_Py_IDENTIFIER(clear);
|
||||
if (_PyObject_CallMethodIdNoArgs(modules, &PyId_clear) == NULL) {
|
||||
PyErr_WriteUnraisable(NULL);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
finalize_restore_builtins(PyThreadState *tstate)
|
||||
{
|
||||
PyInterpreterState *interp = tstate->interp;
|
||||
PyObject *dict = PyDict_Copy(interp->builtins);
|
||||
if (dict == NULL) {
|
||||
PyErr_WriteUnraisable(NULL);
|
||||
}
|
||||
PyDict_Clear(interp->builtins);
|
||||
if (PyDict_Update(interp->builtins, interp->builtins_copy)) {
|
||||
_PyErr_Clear(tstate);
|
||||
}
|
||||
Py_XDECREF(dict);
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
finalize_modules_clear_weaklist(PyInterpreterState *interp,
|
||||
PyObject *weaklist, int verbose)
|
||||
{
|
||||
// First clear modules imported later
|
||||
for (Py_ssize_t i = PyList_GET_SIZE(weaklist) - 1; i >= 0; i--) {
|
||||
PyObject *tup = PyList_GET_ITEM(weaklist, i);
|
||||
PyObject *name = PyTuple_GET_ITEM(tup, 0);
|
||||
PyObject *mod = PyWeakref_GET_OBJECT(PyTuple_GET_ITEM(tup, 1));
|
||||
if (mod == Py_None) {
|
||||
continue;
|
||||
}
|
||||
assert(PyModule_Check(mod));
|
||||
PyObject *dict = PyModule_GetDict(mod);
|
||||
if (dict == interp->builtins || dict == interp->sysdict) {
|
||||
continue;
|
||||
}
|
||||
Py_INCREF(mod);
|
||||
if (verbose && PyUnicode_Check(name)) {
|
||||
PySys_FormatStderr("# cleanup[3] wiping %U\n", name);
|
||||
}
|
||||
_PyModule_Clear(mod);
|
||||
Py_DECREF(mod);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
finalize_clear_sys_builtins_dict(PyInterpreterState *interp, int verbose)
|
||||
{
|
||||
// Clear sys dict
|
||||
if (verbose) {
|
||||
PySys_FormatStderr("# cleanup[3] wiping sys\n");
|
||||
}
|
||||
_PyModule_ClearDict(interp->sysdict);
|
||||
|
||||
// Clear builtins dict
|
||||
if (verbose) {
|
||||
PySys_FormatStderr("# cleanup[3] wiping builtins\n");
|
||||
}
|
||||
_PyModule_ClearDict(interp->builtins);
|
||||
}
|
||||
|
||||
|
||||
/* Clear modules, as good as we can */
|
||||
static void
|
||||
finalize_modules(PyThreadState *tstate)
|
||||
{
|
||||
PyInterpreterState *interp = tstate->interp;
|
||||
PyObject *modules = interp->modules;
|
||||
if (modules == NULL) {
|
||||
// Already done
|
||||
return;
|
||||
}
|
||||
int verbose = _PyInterpreterState_GetConfig(interp)->verbose;
|
||||
|
||||
// Delete some special builtins._ and sys attributes first. These are
|
||||
// common places where user values hide and people complain when their
|
||||
// destructors fail. Since the modules containing them are
|
||||
// deleted *last* of all, they would come too late in the normal
|
||||
// destruction order. Sigh.
|
||||
//
|
||||
// XXX Perhaps these precautions are obsolete. Who knows?
|
||||
finalize_modules_delete_special(tstate, verbose);
|
||||
|
||||
// Remove all modules from sys.modules, hoping that garbage collection
|
||||
// can reclaim most of them: set all sys.modules values to None.
|
||||
//
|
||||
// We prepare a list which will receive (name, weakref) tuples of
|
||||
// modules when they are removed from sys.modules. The name is used
|
||||
// for diagnosis messages (in verbose mode), while the weakref helps
|
||||
// detect those modules which have been held alive.
|
||||
PyObject *weaklist = finalize_remove_modules(modules, verbose);
|
||||
|
||||
// Clear the modules dict
|
||||
finalize_clear_modules_dict(modules);
|
||||
|
||||
// Restore the original builtins dict, to ensure that any
|
||||
// user data gets cleared.
|
||||
finalize_restore_builtins(tstate);
|
||||
|
||||
// Collect garbage
|
||||
_PyGC_CollectNoFail(tstate);
|
||||
|
||||
// Dump GC stats before it's too late, since it uses the warnings
|
||||
// machinery.
|
||||
_PyGC_DumpShutdownStats(tstate);
|
||||
|
||||
if (weaklist != NULL) {
|
||||
// Now, if there are any modules left alive, clear their globals to
|
||||
// minimize potential leaks. All C extension modules actually end
|
||||
// up here, since they are kept alive in the interpreter state.
|
||||
//
|
||||
// The special treatment of "builtins" here is because even
|
||||
// when it's not referenced as a module, its dictionary is
|
||||
// referenced by almost every module's __builtins__. Since
|
||||
// deleting a module clears its dictionary (even if there are
|
||||
// references left to it), we need to delete the "builtins"
|
||||
// module last. Likewise, we don't delete sys until the very
|
||||
// end because it is implicitly referenced (e.g. by print).
|
||||
//
|
||||
// Since dict is ordered in CPython 3.6+, modules are saved in
|
||||
// importing order. First clear modules imported later.
|
||||
finalize_modules_clear_weaklist(interp, weaklist, verbose);
|
||||
Py_DECREF(weaklist);
|
||||
}
|
||||
|
||||
// Clear sys and builtins modules dict
|
||||
finalize_clear_sys_builtins_dict(interp, verbose);
|
||||
|
||||
// Clear module dict copies stored in the interpreter state:
|
||||
// clear PyInterpreterState.modules_by_index and
|
||||
// clear PyModuleDef.m_base.m_copy (of extensions not using the multi-phase
|
||||
// initialization API)
|
||||
_PyInterpreterState_ClearModules(interp);
|
||||
|
||||
// Clear and delete the modules directory. Actual modules will
|
||||
// still be there only if imported during the execution of some
|
||||
// destructor.
|
||||
Py_SETREF(interp->modules, NULL);
|
||||
|
||||
// Collect garbage once more
|
||||
_PyGC_CollectNoFail(tstate);
|
||||
}
|
||||
|
||||
|
||||
/* Flush stdout and stderr */
|
||||
|
||||
static int
|
||||
|
|
@ -1210,6 +1495,7 @@ file_is_closed(PyObject *fobj)
|
|||
return r > 0;
|
||||
}
|
||||
|
||||
|
||||
static int
|
||||
flush_std_files(void)
|
||||
{
|
||||
|
|
@ -1417,7 +1703,7 @@ Py_FinalizeEx(void)
|
|||
PyGC_Collect();
|
||||
|
||||
/* Destroy all modules */
|
||||
_PyImport_Cleanup(tstate);
|
||||
finalize_modules(tstate);
|
||||
|
||||
/* Print debug stats if any */
|
||||
_PyEval_Fini();
|
||||
|
|
@ -1660,7 +1946,8 @@ Py_EndInterpreter(PyThreadState *tstate)
|
|||
Py_FatalError("not the last thread");
|
||||
}
|
||||
|
||||
_PyImport_Cleanup(tstate);
|
||||
finalize_modules(tstate);
|
||||
|
||||
finalize_interp_clear(tstate);
|
||||
finalize_interp_delete(tstate);
|
||||
}
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue