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-rw-r--r--Python/import.c133
1 files changed, 85 insertions, 48 deletions
diff --git a/Python/import.c b/Python/import.c
index 26261e1..fad54e6 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -204,8 +204,11 @@ _PyImport_ReInitLock(void)
if (import_lock_level > 1) {
/* Forked as a side effect of import */
long me = PyThread_get_thread_ident();
- PyThread_acquire_lock(import_lock, 0);
- /* XXX: can the previous line fail? */
+ /* The following could fail if the lock is already held, but forking as
+ a side-effect of an import is a) rare, b) nuts, and c) difficult to
+ do thanks to the lock only being held when doing individual module
+ locks per import. */
+ PyThread_acquire_lock(import_lock, NOWAIT_LOCK);
import_lock_thread = me;
import_lock_level--;
} else {
@@ -292,6 +295,30 @@ static char* sys_files[] = {
NULL
};
+static int
+is_essential_module(PyObject *name)
+{
+ Py_ssize_t name_len;
+ char *name_str = PyUnicode_AsUTF8AndSize(name, &name_len);
+
+ if (name_str == NULL) {
+ PyErr_Clear();
+ return 0;
+ }
+ if (strcmp(name_str, "builtins") == 0)
+ return 1;
+ if (strcmp(name_str, "sys") == 0)
+ return 1;
+ /* These are all needed for stderr to still function */
+ if (strcmp(name_str, "codecs") == 0)
+ return 1;
+ if (strcmp(name_str, "_codecs") == 0)
+ return 1;
+ if (strncmp(name_str, "encodings.", 10) == 0)
+ return 1;
+ return 0;
+}
+
/* Un-initialize things, as good as we can */
@@ -371,9 +398,7 @@ PyImport_Cleanup(void)
if (value->ob_refcnt != 1)
continue;
if (PyUnicode_Check(key) && PyModule_Check(value)) {
- if (PyUnicode_CompareWithASCIIString(key, "builtins") == 0)
- continue;
- if (PyUnicode_CompareWithASCIIString(key, "sys") == 0)
+ if (is_essential_module(key))
continue;
if (Py_VerboseFlag)
PySys_FormatStderr(
@@ -389,9 +414,7 @@ PyImport_Cleanup(void)
pos = 0;
while (PyDict_Next(modules, &pos, &key, &value)) {
if (PyUnicode_Check(key) && PyModule_Check(value)) {
- if (PyUnicode_CompareWithASCIIString(key, "builtins") == 0)
- continue;
- if (PyUnicode_CompareWithASCIIString(key, "sys") == 0)
+ if (is_essential_module(key))
continue;
if (Py_VerboseFlag)
PySys_FormatStderr("# cleanup[2] %U\n", key);
@@ -400,24 +423,28 @@ PyImport_Cleanup(void)
}
}
- /* Next, delete sys and builtins (in that order) */
- value = PyDict_GetItemString(modules, "sys");
- if (value != NULL && PyModule_Check(value)) {
- if (Py_VerboseFlag)
- PySys_WriteStderr("# cleanup sys\n");
- _PyModule_Clear(value);
- PyDict_SetItemString(modules, "sys", Py_None);
- }
- value = PyDict_GetItemString(modules, "builtins");
- if (value != NULL && PyModule_Check(value)) {
- if (Py_VerboseFlag)
- PySys_WriteStderr("# cleanup builtins\n");
- _PyModule_Clear(value);
- PyDict_SetItemString(modules, "builtins", Py_None);
+ /* Collect garbage remaining after deleting the modules. Mostly
+ reference cycles created by classes. */
+ PyGC_Collect();
+
+ /* Dump GC stats before it's too late, since it uses the warnings
+ machinery. */
+ _PyGC_DumpShutdownStats();
+
+ /* Next, delete all remaining modules */
+ pos = 0;
+ while (PyDict_Next(modules, &pos, &key, &value)) {
+ if (PyUnicode_Check(key) && PyModule_Check(value)) {
+ if (Py_VerboseFlag)
+ PySys_FormatStderr("# cleanup[3] %U\n", key);
+ _PyModule_Clear(value);
+ PyDict_SetItem(modules, key, Py_None);
+ }
}
/* Finally, clear and delete the modules directory */
PyDict_Clear(modules);
+ _PyGC_CollectNoFail();
interp->modules = NULL;
Py_DECREF(modules);
}
@@ -451,12 +478,12 @@ PyImport_GetMagicTag(void)
/* Magic for extension modules (built-in as well as dynamically
loaded). To prevent initializing an extension module more than
- once, we keep a static dictionary 'extensions' keyed by module name
- (for built-in modules) or by filename (for dynamically loaded
- modules), containing these modules. A copy of the module's
- dictionary is stored by calling _PyImport_FixupExtensionObject()
- immediately after the module initialization function succeeds. A
- copy can be retrieved from there by calling
+ once, we keep a static dictionary 'extensions' keyed by the tuple
+ (module name, module name) (for built-in modules) or by
+ (filename, module name) (for dynamically loaded modules), containing these
+ modules. A copy of the module's dictionary is stored by calling
+ _PyImport_FixupExtensionObject() immediately after the module initialization
+ function succeeds. A copy can be retrieved from there by calling
_PyImport_FindExtensionObject().
Modules which do support multiple initialization set their m_size
@@ -469,8 +496,9 @@ int
_PyImport_FixupExtensionObject(PyObject *mod, PyObject *name,
PyObject *filename)
{
- PyObject *modules, *dict;
+ PyObject *modules, *dict, *key;
struct PyModuleDef *def;
+ int res;
if (extensions == NULL) {
extensions = PyDict_New();
if (extensions == NULL)
@@ -507,7 +535,13 @@ _PyImport_FixupExtensionObject(PyObject *mod, PyObject *name,
if (def->m_base.m_copy == NULL)
return -1;
}
- PyDict_SetItem(extensions, filename, (PyObject*)def);
+ key = PyTuple_Pack(2, filename, name);
+ if (key == NULL)
+ return -1;
+ res = PyDict_SetItem(extensions, key, (PyObject *)def);
+ Py_DECREF(key);
+ if (res < 0)
+ return -1;
return 0;
}
@@ -527,11 +561,15 @@ _PyImport_FixupBuiltin(PyObject *mod, char *name)
PyObject *
_PyImport_FindExtensionObject(PyObject *name, PyObject *filename)
{
- PyObject *mod, *mdict;
+ PyObject *mod, *mdict, *key;
PyModuleDef* def;
if (extensions == NULL)
return NULL;
- def = (PyModuleDef*)PyDict_GetItem(extensions, filename);
+ key = PyTuple_Pack(2, filename, name);
+ if (key == NULL)
+ return NULL;
+ def = (PyModuleDef *)PyDict_GetItem(extensions, key);
+ Py_DECREF(key);
if (def == NULL)
return NULL;
if (def->m_size == -1) {
@@ -690,7 +728,7 @@ PyImport_ExecCodeModuleWithPathnames(char *name, PyObject *co, char *pathname,
"no interpreter!");
}
- pathobj = _PyObject_CallMethodObjIdArgs(interp->importlib,
+ pathobj = _PyObject_CallMethodIdObjArgs(interp->importlib,
&PyId__get_sourcefile, cpathobj,
NULL);
if (pathobj == NULL)
@@ -832,7 +870,7 @@ imp_fix_co_filename(PyObject *self, PyObject *args)
/* Forward */
-static struct _frozen * find_frozen(PyObject *);
+static const struct _frozen * find_frozen(PyObject *);
/* Helper to test for built-in module */
@@ -969,10 +1007,10 @@ init_builtin(PyObject *name)
/* Frozen modules */
-static struct _frozen *
+static const struct _frozen *
find_frozen(PyObject *name)
{
- struct _frozen *p;
+ const struct _frozen *p;
if (name == NULL)
return NULL;
@@ -989,7 +1027,7 @@ find_frozen(PyObject *name)
static PyObject *
get_frozen_object(PyObject *name)
{
- struct _frozen *p = find_frozen(name);
+ const struct _frozen *p = find_frozen(name);
int size;
if (p == NULL) {
@@ -1013,7 +1051,7 @@ get_frozen_object(PyObject *name)
static PyObject *
is_frozen_package(PyObject *name)
{
- struct _frozen *p = find_frozen(name);
+ const struct _frozen *p = find_frozen(name);
int size;
if (p == NULL) {
@@ -1040,7 +1078,7 @@ is_frozen_package(PyObject *name)
int
PyImport_ImportFrozenModuleObject(PyObject *name)
{
- struct _frozen *p;
+ const struct _frozen *p;
PyObject *co, *m, *path;
int ispackage;
int size;
@@ -1069,19 +1107,17 @@ PyImport_ImportFrozenModuleObject(PyObject *name)
goto err_return;
}
if (ispackage) {
- /* Set __path__ to the package name */
+ /* Set __path__ to the empty list */
PyObject *d, *l;
int err;
m = PyImport_AddModuleObject(name);
if (m == NULL)
goto err_return;
d = PyModule_GetDict(m);
- l = PyList_New(1);
+ l = PyList_New(0);
if (l == NULL) {
goto err_return;
}
- Py_INCREF(name);
- PyList_SET_ITEM(l, 0, name);
err = PyDict_SetItemString(d, "__path__", l);
Py_DECREF(l);
if (err != 0)
@@ -1400,7 +1436,8 @@ PyImport_ImportModuleLevelObject(PyObject *name, PyObject *given_globals,
PyObject *msg = PyUnicode_FromFormat("import of %R halted; "
"None in sys.modules", abs_name);
if (msg != NULL) {
- PyErr_SetImportError(msg, abs_name, NULL);
+ PyErr_SetImportErrorSubclass(PyExc_ModuleNotFoundError, msg,
+ abs_name, NULL);
Py_DECREF(msg);
}
mod = NULL;
@@ -1427,7 +1464,7 @@ PyImport_ImportModuleLevelObject(PyObject *name, PyObject *given_globals,
}
if (initializing > 0) {
/* _bootstrap._lock_unlock_module() releases the import lock */
- value = _PyObject_CallMethodObjIdArgs(interp->importlib,
+ value = _PyObject_CallMethodIdObjArgs(interp->importlib,
&PyId__lock_unlock_module, abs_name,
NULL);
if (value == NULL)
@@ -1445,7 +1482,7 @@ PyImport_ImportModuleLevelObject(PyObject *name, PyObject *given_globals,
}
else {
/* _bootstrap._find_and_load() releases the import lock */
- mod = _PyObject_CallMethodObjIdArgs(interp->importlib,
+ mod = _PyObject_CallMethodIdObjArgs(interp->importlib,
&PyId__find_and_load, abs_name,
builtins_import, NULL);
if (mod == NULL) {
@@ -1514,7 +1551,7 @@ PyImport_ImportModuleLevelObject(PyObject *name, PyObject *given_globals,
}
}
else {
- final_mod = _PyObject_CallMethodObjIdArgs(interp->importlib,
+ final_mod = _PyObject_CallMethodIdObjArgs(interp->importlib,
&PyId__handle_fromlist, mod,
fromlist, builtins_import,
NULL);
@@ -1768,7 +1805,7 @@ static PyObject *
imp_is_frozen(PyObject *self, PyObject *args)
{
PyObject *name;
- struct _frozen *p;
+ const struct _frozen *p;
if (!PyArg_ParseTuple(args, "U:is_frozen", &name))
return NULL;
p = find_frozen(name);
generated by cgit v0.12 at 2025-05-08 19:13:53 (GMT)