cpython/Objects/moduleobject.c
Victor Stinner 250035d134
bpo-42923: Dump extension modules on fatal error (GH-24207)
The Py_FatalError() function and the faulthandler module now dump the
list of extension modules on a fatal error.

Add _Py_DumpExtensionModules() and _PyModule_IsExtension() internal
functions.
2021-01-18 20:47:13 +01:00

897 lines
26 KiB
C

/* Module object implementation */
#include "Python.h"
#include "pycore_interp.h" // PyInterpreterState.importlib
#include "pycore_pystate.h" // _PyInterpreterState_GET()
#include "structmember.h" // PyMemberDef
static Py_ssize_t max_module_number;
_Py_IDENTIFIER(__doc__);
_Py_IDENTIFIER(__name__);
_Py_IDENTIFIER(__spec__);
typedef struct {
PyObject_HEAD
PyObject *md_dict;
struct PyModuleDef *md_def;
void *md_state;
PyObject *md_weaklist;
PyObject *md_name; /* for logging purposes after md_dict is cleared */
} PyModuleObject;
static PyMemberDef module_members[] = {
{"__dict__", T_OBJECT, offsetof(PyModuleObject, md_dict), READONLY},
{0}
};
PyTypeObject PyModuleDef_Type = {
PyVarObject_HEAD_INIT(&PyType_Type, 0)
"moduledef", /* tp_name */
sizeof(struct PyModuleDef), /* tp_basicsize */
0, /* tp_itemsize */
};
int
_PyModule_IsExtension(PyObject *obj)
{
if (!PyModule_Check(obj)) {
return 0;
}
PyModuleObject *module = (PyModuleObject*)obj;
struct PyModuleDef *def = module->md_def;
return (def != NULL && def->m_methods != NULL);
}
PyObject*
PyModuleDef_Init(struct PyModuleDef* def)
{
if (PyType_Ready(&PyModuleDef_Type) < 0)
return NULL;
if (def->m_base.m_index == 0) {
max_module_number++;
Py_SET_REFCNT(def, 1);
Py_SET_TYPE(def, &PyModuleDef_Type);
def->m_base.m_index = max_module_number;
}
return (PyObject*)def;
}
static int
module_init_dict(PyModuleObject *mod, PyObject *md_dict,
PyObject *name, PyObject *doc)
{
_Py_IDENTIFIER(__package__);
_Py_IDENTIFIER(__loader__);
if (md_dict == NULL)
return -1;
if (doc == NULL)
doc = Py_None;
if (_PyDict_SetItemId(md_dict, &PyId___name__, name) != 0)
return -1;
if (_PyDict_SetItemId(md_dict, &PyId___doc__, doc) != 0)
return -1;
if (_PyDict_SetItemId(md_dict, &PyId___package__, Py_None) != 0)
return -1;
if (_PyDict_SetItemId(md_dict, &PyId___loader__, Py_None) != 0)
return -1;
if (_PyDict_SetItemId(md_dict, &PyId___spec__, Py_None) != 0)
return -1;
if (PyUnicode_CheckExact(name)) {
Py_INCREF(name);
Py_XSETREF(mod->md_name, name);
}
return 0;
}
PyObject *
PyModule_NewObject(PyObject *name)
{
PyModuleObject *m;
m = PyObject_GC_New(PyModuleObject, &PyModule_Type);
if (m == NULL)
return NULL;
m->md_def = NULL;
m->md_state = NULL;
m->md_weaklist = NULL;
m->md_name = NULL;
m->md_dict = PyDict_New();
if (module_init_dict(m, m->md_dict, name, NULL) != 0)
goto fail;
PyObject_GC_Track(m);
return (PyObject *)m;
fail:
Py_DECREF(m);
return NULL;
}
PyObject *
PyModule_New(const char *name)
{
PyObject *nameobj, *module;
nameobj = PyUnicode_FromString(name);
if (nameobj == NULL)
return NULL;
module = PyModule_NewObject(nameobj);
Py_DECREF(nameobj);
return module;
}
/* Check API/ABI version
* Issues a warning on mismatch, which is usually not fatal.
* Returns 0 if an exception is raised.
*/
static int
check_api_version(const char *name, int module_api_version)
{
if (module_api_version != PYTHON_API_VERSION && module_api_version != PYTHON_ABI_VERSION) {
int err;
err = PyErr_WarnFormat(PyExc_RuntimeWarning, 1,
"Python C API version mismatch for module %.100s: "
"This Python has API version %d, module %.100s has version %d.",
name,
PYTHON_API_VERSION, name, module_api_version);
if (err)
return 0;
}
return 1;
}
static int
_add_methods_to_object(PyObject *module, PyObject *name, PyMethodDef *functions)
{
PyObject *func;
PyMethodDef *fdef;
for (fdef = functions; fdef->ml_name != NULL; fdef++) {
if ((fdef->ml_flags & METH_CLASS) ||
(fdef->ml_flags & METH_STATIC)) {
PyErr_SetString(PyExc_ValueError,
"module functions cannot set"
" METH_CLASS or METH_STATIC");
return -1;
}
func = PyCFunction_NewEx(fdef, (PyObject*)module, name);
if (func == NULL) {
return -1;
}
if (PyObject_SetAttrString(module, fdef->ml_name, func) != 0) {
Py_DECREF(func);
return -1;
}
Py_DECREF(func);
}
return 0;
}
PyObject *
PyModule_Create2(struct PyModuleDef* module, int module_api_version)
{
if (!_PyImport_IsInitialized(_PyInterpreterState_GET())) {
PyErr_SetString(PyExc_SystemError,
"Python import machinery not initialized");
return NULL;
}
return _PyModule_CreateInitialized(module, module_api_version);
}
PyObject *
_PyModule_CreateInitialized(struct PyModuleDef* module, int module_api_version)
{
const char* name;
PyModuleObject *m;
if (!PyModuleDef_Init(module))
return NULL;
name = module->m_name;
if (!check_api_version(name, module_api_version)) {
return NULL;
}
if (module->m_slots) {
PyErr_Format(
PyExc_SystemError,
"module %s: PyModule_Create is incompatible with m_slots", name);
return NULL;
}
/* Make sure name is fully qualified.
This is a bit of a hack: when the shared library is loaded,
the module name is "package.module", but the module calls
PyModule_Create*() with just "module" for the name. The shared
library loader squirrels away the true name of the module in
_Py_PackageContext, and PyModule_Create*() will substitute this
(if the name actually matches).
*/
if (_Py_PackageContext != NULL) {
const char *p = strrchr(_Py_PackageContext, '.');
if (p != NULL && strcmp(module->m_name, p+1) == 0) {
name = _Py_PackageContext;
_Py_PackageContext = NULL;
}
}
if ((m = (PyModuleObject*)PyModule_New(name)) == NULL)
return NULL;
if (module->m_size > 0) {
m->md_state = PyMem_Malloc(module->m_size);
if (!m->md_state) {
PyErr_NoMemory();
Py_DECREF(m);
return NULL;
}
memset(m->md_state, 0, module->m_size);
}
if (module->m_methods != NULL) {
if (PyModule_AddFunctions((PyObject *) m, module->m_methods) != 0) {
Py_DECREF(m);
return NULL;
}
}
if (module->m_doc != NULL) {
if (PyModule_SetDocString((PyObject *) m, module->m_doc) != 0) {
Py_DECREF(m);
return NULL;
}
}
m->md_def = module;
return (PyObject*)m;
}
PyObject *
PyModule_FromDefAndSpec2(struct PyModuleDef* def, PyObject *spec, int module_api_version)
{
PyModuleDef_Slot* cur_slot;
PyObject *(*create)(PyObject *, PyModuleDef*) = NULL;
PyObject *nameobj;
PyObject *m = NULL;
int has_execution_slots = 0;
const char *name;
int ret;
PyModuleDef_Init(def);
nameobj = PyObject_GetAttrString(spec, "name");
if (nameobj == NULL) {
return NULL;
}
name = PyUnicode_AsUTF8(nameobj);
if (name == NULL) {
goto error;
}
if (!check_api_version(name, module_api_version)) {
goto error;
}
if (def->m_size < 0) {
PyErr_Format(
PyExc_SystemError,
"module %s: m_size may not be negative for multi-phase initialization",
name);
goto error;
}
for (cur_slot = def->m_slots; cur_slot && cur_slot->slot; cur_slot++) {
if (cur_slot->slot == Py_mod_create) {
if (create) {
PyErr_Format(
PyExc_SystemError,
"module %s has multiple create slots",
name);
goto error;
}
create = cur_slot->value;
} else if (cur_slot->slot < 0 || cur_slot->slot > _Py_mod_LAST_SLOT) {
PyErr_Format(
PyExc_SystemError,
"module %s uses unknown slot ID %i",
name, cur_slot->slot);
goto error;
} else {
has_execution_slots = 1;
}
}
if (create) {
m = create(spec, def);
if (m == NULL) {
if (!PyErr_Occurred()) {
PyErr_Format(
PyExc_SystemError,
"creation of module %s failed without setting an exception",
name);
}
goto error;
} else {
if (PyErr_Occurred()) {
PyErr_Format(PyExc_SystemError,
"creation of module %s raised unreported exception",
name);
goto error;
}
}
} else {
m = PyModule_NewObject(nameobj);
if (m == NULL) {
goto error;
}
}
if (PyModule_Check(m)) {
((PyModuleObject*)m)->md_state = NULL;
((PyModuleObject*)m)->md_def = def;
} else {
if (def->m_size > 0 || def->m_traverse || def->m_clear || def->m_free) {
PyErr_Format(
PyExc_SystemError,
"module %s is not a module object, but requests module state",
name);
goto error;
}
if (has_execution_slots) {
PyErr_Format(
PyExc_SystemError,
"module %s specifies execution slots, but did not create "
"a ModuleType instance",
name);
goto error;
}
}
if (def->m_methods != NULL) {
ret = _add_methods_to_object(m, nameobj, def->m_methods);
if (ret != 0) {
goto error;
}
}
if (def->m_doc != NULL) {
ret = PyModule_SetDocString(m, def->m_doc);
if (ret != 0) {
goto error;
}
}
Py_DECREF(nameobj);
return m;
error:
Py_DECREF(nameobj);
Py_XDECREF(m);
return NULL;
}
int
PyModule_ExecDef(PyObject *module, PyModuleDef *def)
{
PyModuleDef_Slot *cur_slot;
const char *name;
int ret;
name = PyModule_GetName(module);
if (name == NULL) {
return -1;
}
if (def->m_size >= 0) {
PyModuleObject *md = (PyModuleObject*)module;
if (md->md_state == NULL) {
/* Always set a state pointer; this serves as a marker to skip
* multiple initialization (importlib.reload() is no-op) */
md->md_state = PyMem_Malloc(def->m_size);
if (!md->md_state) {
PyErr_NoMemory();
return -1;
}
memset(md->md_state, 0, def->m_size);
}
}
if (def->m_slots == NULL) {
return 0;
}
for (cur_slot = def->m_slots; cur_slot && cur_slot->slot; cur_slot++) {
switch (cur_slot->slot) {
case Py_mod_create:
/* handled in PyModule_FromDefAndSpec2 */
break;
case Py_mod_exec:
ret = ((int (*)(PyObject *))cur_slot->value)(module);
if (ret != 0) {
if (!PyErr_Occurred()) {
PyErr_Format(
PyExc_SystemError,
"execution of module %s failed without setting an exception",
name);
}
return -1;
}
if (PyErr_Occurred()) {
PyErr_Format(
PyExc_SystemError,
"execution of module %s raised unreported exception",
name);
return -1;
}
break;
default:
PyErr_Format(
PyExc_SystemError,
"module %s initialized with unknown slot %i",
name, cur_slot->slot);
return -1;
}
}
return 0;
}
int
PyModule_AddFunctions(PyObject *m, PyMethodDef *functions)
{
int res;
PyObject *name = PyModule_GetNameObject(m);
if (name == NULL) {
return -1;
}
res = _add_methods_to_object(m, name, functions);
Py_DECREF(name);
return res;
}
int
PyModule_SetDocString(PyObject *m, const char *doc)
{
PyObject *v;
v = PyUnicode_FromString(doc);
if (v == NULL || _PyObject_SetAttrId(m, &PyId___doc__, v) != 0) {
Py_XDECREF(v);
return -1;
}
Py_DECREF(v);
return 0;
}
PyObject *
PyModule_GetDict(PyObject *m)
{
PyObject *d;
if (!PyModule_Check(m)) {
PyErr_BadInternalCall();
return NULL;
}
d = ((PyModuleObject *)m) -> md_dict;
assert(d != NULL);
return d;
}
PyObject*
PyModule_GetNameObject(PyObject *m)
{
PyObject *d;
PyObject *name;
if (!PyModule_Check(m)) {
PyErr_BadArgument();
return NULL;
}
d = ((PyModuleObject *)m)->md_dict;
if (d == NULL ||
(name = _PyDict_GetItemIdWithError(d, &PyId___name__)) == NULL ||
!PyUnicode_Check(name))
{
if (!PyErr_Occurred()) {
PyErr_SetString(PyExc_SystemError, "nameless module");
}
return NULL;
}
Py_INCREF(name);
return name;
}
const char *
PyModule_GetName(PyObject *m)
{
PyObject *name = PyModule_GetNameObject(m);
if (name == NULL)
return NULL;
Py_DECREF(name); /* module dict has still a reference */
return PyUnicode_AsUTF8(name);
}
PyObject*
PyModule_GetFilenameObject(PyObject *m)
{
_Py_IDENTIFIER(__file__);
PyObject *d;
PyObject *fileobj;
if (!PyModule_Check(m)) {
PyErr_BadArgument();
return NULL;
}
d = ((PyModuleObject *)m)->md_dict;
if (d == NULL ||
(fileobj = _PyDict_GetItemIdWithError(d, &PyId___file__)) == NULL ||
!PyUnicode_Check(fileobj))
{
if (!PyErr_Occurred()) {
PyErr_SetString(PyExc_SystemError, "module filename missing");
}
return NULL;
}
Py_INCREF(fileobj);
return fileobj;
}
const char *
PyModule_GetFilename(PyObject *m)
{
PyObject *fileobj;
const char *utf8;
fileobj = PyModule_GetFilenameObject(m);
if (fileobj == NULL)
return NULL;
utf8 = PyUnicode_AsUTF8(fileobj);
Py_DECREF(fileobj); /* module dict has still a reference */
return utf8;
}
PyModuleDef*
PyModule_GetDef(PyObject* m)
{
if (!PyModule_Check(m)) {
PyErr_BadArgument();
return NULL;
}
return ((PyModuleObject *)m)->md_def;
}
void*
PyModule_GetState(PyObject* m)
{
if (!PyModule_Check(m)) {
PyErr_BadArgument();
return NULL;
}
return ((PyModuleObject *)m)->md_state;
}
void
_PyModule_Clear(PyObject *m)
{
PyObject *d = ((PyModuleObject *)m)->md_dict;
if (d != NULL)
_PyModule_ClearDict(d);
}
void
_PyModule_ClearDict(PyObject *d)
{
/* To make the execution order of destructors for global
objects a bit more predictable, we first zap all objects
whose name starts with a single underscore, before we clear
the entire dictionary. We zap them by replacing them with
None, rather than deleting them from the dictionary, to
avoid rehashing the dictionary (to some extent). */
Py_ssize_t pos;
PyObject *key, *value;
int verbose = _Py_GetConfig()->verbose;
/* First, clear only names starting with a single underscore */
pos = 0;
while (PyDict_Next(d, &pos, &key, &value)) {
if (value != Py_None && PyUnicode_Check(key)) {
if (PyUnicode_READ_CHAR(key, 0) == '_' &&
PyUnicode_READ_CHAR(key, 1) != '_') {
if (verbose > 1) {
const char *s = PyUnicode_AsUTF8(key);
if (s != NULL)
PySys_WriteStderr("# clear[1] %s\n", s);
else
PyErr_Clear();
}
if (PyDict_SetItem(d, key, Py_None) != 0) {
PyErr_WriteUnraisable(NULL);
}
}
}
}
/* Next, clear all names except for __builtins__ */
pos = 0;
while (PyDict_Next(d, &pos, &key, &value)) {
if (value != Py_None && PyUnicode_Check(key)) {
if (PyUnicode_READ_CHAR(key, 0) != '_' ||
!_PyUnicode_EqualToASCIIString(key, "__builtins__"))
{
if (verbose > 1) {
const char *s = PyUnicode_AsUTF8(key);
if (s != NULL)
PySys_WriteStderr("# clear[2] %s\n", s);
else
PyErr_Clear();
}
if (PyDict_SetItem(d, key, Py_None) != 0) {
PyErr_WriteUnraisable(NULL);
}
}
}
}
/* Note: we leave __builtins__ in place, so that destructors
of non-global objects defined in this module can still use
builtins, in particularly 'None'. */
}
/*[clinic input]
class module "PyModuleObject *" "&PyModule_Type"
[clinic start generated code]*/
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=3e35d4f708ecb6af]*/
#include "clinic/moduleobject.c.h"
/* Methods */
/*[clinic input]
module.__init__
name: unicode
doc: object = None
Create a module object.
The name must be a string; the optional doc argument can have any type.
[clinic start generated code]*/
static int
module___init___impl(PyModuleObject *self, PyObject *name, PyObject *doc)
/*[clinic end generated code: output=e7e721c26ce7aad7 input=57f9e177401e5e1e]*/
{
PyObject *dict = self->md_dict;
if (dict == NULL) {
dict = PyDict_New();
if (dict == NULL)
return -1;
self->md_dict = dict;
}
if (module_init_dict(self, dict, name, doc) < 0)
return -1;
return 0;
}
static void
module_dealloc(PyModuleObject *m)
{
int verbose = _Py_GetConfig()->verbose;
PyObject_GC_UnTrack(m);
if (verbose && m->md_name) {
PySys_FormatStderr("# destroy %U\n", m->md_name);
}
if (m->md_weaklist != NULL)
PyObject_ClearWeakRefs((PyObject *) m);
/* bpo-39824: Don't call m_free() if m_size > 0 and md_state=NULL */
if (m->md_def && m->md_def->m_free
&& (m->md_def->m_size <= 0 || m->md_state != NULL))
{
m->md_def->m_free(m);
}
Py_XDECREF(m->md_dict);
Py_XDECREF(m->md_name);
if (m->md_state != NULL)
PyMem_Free(m->md_state);
Py_TYPE(m)->tp_free((PyObject *)m);
}
static PyObject *
module_repr(PyModuleObject *m)
{
PyInterpreterState *interp = _PyInterpreterState_GET();
return PyObject_CallMethod(interp->importlib, "_module_repr", "O", m);
}
/* Check if the "_initializing" attribute of the module spec is set to true.
Clear the exception and return 0 if spec is NULL.
*/
int
_PyModuleSpec_IsInitializing(PyObject *spec)
{
if (spec != NULL) {
_Py_IDENTIFIER(_initializing);
PyObject *value = _PyObject_GetAttrId(spec, &PyId__initializing);
if (value != NULL) {
int initializing = PyObject_IsTrue(value);
Py_DECREF(value);
if (initializing >= 0) {
return initializing;
}
}
}
PyErr_Clear();
return 0;
}
static PyObject*
module_getattro(PyModuleObject *m, PyObject *name)
{
PyObject *attr, *mod_name, *getattr;
attr = PyObject_GenericGetAttr((PyObject *)m, name);
if (attr || !PyErr_ExceptionMatches(PyExc_AttributeError)) {
return attr;
}
PyErr_Clear();
if (m->md_dict) {
_Py_IDENTIFIER(__getattr__);
getattr = _PyDict_GetItemIdWithError(m->md_dict, &PyId___getattr__);
if (getattr) {
return PyObject_CallOneArg(getattr, name);
}
if (PyErr_Occurred()) {
return NULL;
}
mod_name = _PyDict_GetItemIdWithError(m->md_dict, &PyId___name__);
if (mod_name && PyUnicode_Check(mod_name)) {
Py_INCREF(mod_name);
PyObject *spec = _PyDict_GetItemIdWithError(m->md_dict, &PyId___spec__);
if (spec == NULL && PyErr_Occurred()) {
Py_DECREF(mod_name);
return NULL;
}
Py_XINCREF(spec);
if (_PyModuleSpec_IsInitializing(spec)) {
PyErr_Format(PyExc_AttributeError,
"partially initialized "
"module '%U' has no attribute '%U' "
"(most likely due to a circular import)",
mod_name, name);
}
else {
PyErr_Format(PyExc_AttributeError,
"module '%U' has no attribute '%U'",
mod_name, name);
}
Py_XDECREF(spec);
Py_DECREF(mod_name);
return NULL;
}
else if (PyErr_Occurred()) {
return NULL;
}
}
PyErr_Format(PyExc_AttributeError,
"module has no attribute '%U'", name);
return NULL;
}
static int
module_traverse(PyModuleObject *m, visitproc visit, void *arg)
{
/* bpo-39824: Don't call m_traverse() if m_size > 0 and md_state=NULL */
if (m->md_def && m->md_def->m_traverse
&& (m->md_def->m_size <= 0 || m->md_state != NULL))
{
int res = m->md_def->m_traverse((PyObject*)m, visit, arg);
if (res)
return res;
}
Py_VISIT(m->md_dict);
return 0;
}
static int
module_clear(PyModuleObject *m)
{
/* bpo-39824: Don't call m_clear() if m_size > 0 and md_state=NULL */
if (m->md_def && m->md_def->m_clear
&& (m->md_def->m_size <= 0 || m->md_state != NULL))
{
int res = m->md_def->m_clear((PyObject*)m);
if (PyErr_Occurred()) {
PySys_FormatStderr("Exception ignored in m_clear of module%s%V\n",
m->md_name ? " " : "",
m->md_name, "");
PyErr_WriteUnraisable(NULL);
}
if (res)
return res;
}
Py_CLEAR(m->md_dict);
return 0;
}
static PyObject *
module_dir(PyObject *self, PyObject *args)
{
_Py_IDENTIFIER(__dict__);
_Py_IDENTIFIER(__dir__);
PyObject *result = NULL;
PyObject *dict = _PyObject_GetAttrId(self, &PyId___dict__);
if (dict != NULL) {
if (PyDict_Check(dict)) {
PyObject *dirfunc = _PyDict_GetItemIdWithError(dict, &PyId___dir__);
if (dirfunc) {
result = _PyObject_CallNoArg(dirfunc);
}
else if (!PyErr_Occurred()) {
result = PyDict_Keys(dict);
}
}
else {
const char *name = PyModule_GetName(self);
if (name)
PyErr_Format(PyExc_TypeError,
"%.200s.__dict__ is not a dictionary",
name);
}
}
Py_XDECREF(dict);
return result;
}
static PyMethodDef module_methods[] = {
{"__dir__", module_dir, METH_NOARGS,
PyDoc_STR("__dir__() -> list\nspecialized dir() implementation")},
{0}
};
PyTypeObject PyModule_Type = {
PyVarObject_HEAD_INIT(&PyType_Type, 0)
"module", /* tp_name */
sizeof(PyModuleObject), /* tp_basicsize */
0, /* tp_itemsize */
(destructor)module_dealloc, /* tp_dealloc */
0, /* tp_vectorcall_offset */
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_as_async */
(reprfunc)module_repr, /* tp_repr */
0, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */
0, /* tp_hash */
0, /* tp_call */
0, /* tp_str */
(getattrofunc)module_getattro, /* tp_getattro */
PyObject_GenericSetAttr, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
Py_TPFLAGS_BASETYPE, /* tp_flags */
module___init____doc__, /* tp_doc */
(traverseproc)module_traverse, /* tp_traverse */
(inquiry)module_clear, /* tp_clear */
0, /* tp_richcompare */
offsetof(PyModuleObject, md_weaklist), /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
module_methods, /* tp_methods */
module_members, /* tp_members */
0, /* tp_getset */
0, /* tp_base */
0, /* tp_dict */
0, /* tp_descr_get */
0, /* tp_descr_set */
offsetof(PyModuleObject, md_dict), /* tp_dictoffset */
module___init__, /* tp_init */
PyType_GenericAlloc, /* tp_alloc */
PyType_GenericNew, /* tp_new */
PyObject_GC_Del, /* tp_free */
};