diff options
Diffstat (limited to 'Python/import.c')
| -rw-r--r-- | Python/import.c | 123 |
1 files changed, 80 insertions, 43 deletions
diff --git a/Python/import.c b/Python/import.c index 26261e1914..1fbafecc1b 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); @@ -400,20 +423,23 @@ 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 */ @@ -451,12 +477,12 @@ 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 +495,9 @@ 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 +534,13 @@ _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 +560,15 @@ _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 +727,7 @@ 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 +869,7 @@ 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 +1006,10 @@ 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 +1026,7 @@ 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 +1050,7 @@ 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 +1077,7 @@ 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; @@ -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); |