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object.c
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object.c
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/* Generic object operations; and implementation of None */
#include "Python.h"
#include "frameobject.h"
#ifdef __cplusplus
extern "C" {
#endif
_Py_IDENTIFIER(Py_Repr);
_Py_IDENTIFIER(__bytes__);
_Py_IDENTIFIER(__dir__);
_Py_IDENTIFIER(__isabstractmethod__);
_Py_IDENTIFIER(builtins);
#ifdef Py_REF_DEBUG
Py_ssize_t _Py_RefTotal;
Py_ssize_t
_Py_GetRefTotal(void)
{
PyObject *o;
Py_ssize_t total = _Py_RefTotal;
o = _PySet_Dummy;
if (o != NULL)
total -= o->ob_refcnt;
return total;
}
void
_PyDebug_PrintTotalRefs(void) {
PyObject *xoptions, *value;
_Py_IDENTIFIER(showrefcount);
xoptions = PySys_GetXOptions();
if (xoptions == NULL)
return;
value = _PyDict_GetItemId(xoptions, &PyId_showrefcount);
if (value == Py_True)
fprintf(stderr,
"[%" PY_FORMAT_SIZE_T "d refs, "
"%" PY_FORMAT_SIZE_T "d blocks]\n",
_Py_GetRefTotal(), _Py_GetAllocatedBlocks());
}
#endif /* Py_REF_DEBUG */
/* Object allocation routines used by NEWOBJ and NEWVAROBJ macros.
These are used by the individual routines for object creation.
Do not call them otherwise, they do not initialize the object! */
#ifdef Py_TRACE_REFS
/* Head of circular doubly-linked list of all objects. These are linked
* together via the _ob_prev and _ob_next members of a PyObject, which
* exist only in a Py_TRACE_REFS build.
*/
static PyObject refchain = {&refchain, &refchain};
/* Insert op at the front of the list of all objects. If force is true,
* op is added even if _ob_prev and _ob_next are non-NULL already. If
* force is false amd _ob_prev or _ob_next are non-NULL, do nothing.
* force should be true if and only if op points to freshly allocated,
* uninitialized memory, or you've unlinked op from the list and are
* relinking it into the front.
* Note that objects are normally added to the list via _Py_NewReference,
* which is called by PyObject_Init. Not all objects are initialized that
* way, though; exceptions include statically allocated type objects, and
* statically allocated singletons (like Py_True and Py_None).
*/
void
_Py_AddToAllObjects(PyObject *op, int force)
{
#ifdef Py_DEBUG
if (!force) {
/* If it's initialized memory, op must be in or out of
* the list unambiguously.
*/
assert((op->_ob_prev == NULL) == (op->_ob_next == NULL));
}
#endif
if (force || op->_ob_prev == NULL) {
op->_ob_next = refchain._ob_next;
op->_ob_prev = &refchain;
refchain._ob_next->_ob_prev = op;
refchain._ob_next = op;
}
}
#endif /* Py_TRACE_REFS */
#ifdef COUNT_ALLOCS
static PyTypeObject *type_list;
/* All types are added to type_list, at least when
they get one object created. That makes them
immortal, which unfortunately contributes to
garbage itself. If unlist_types_without_objects
is set, they will be removed from the type_list
once the last object is deallocated. */
static int unlist_types_without_objects;
extern Py_ssize_t tuple_zero_allocs, fast_tuple_allocs;
extern Py_ssize_t quick_int_allocs, quick_neg_int_allocs;
extern Py_ssize_t null_strings, one_strings;
void
dump_counts(FILE* f)
{
PyTypeObject *tp;
PyObject *xoptions, *value;
_Py_IDENTIFIER(showalloccount);
xoptions = PySys_GetXOptions();
if (xoptions == NULL)
return;
value = _PyDict_GetItemId(xoptions, &PyId_showalloccount);
if (value != Py_True)
return;
for (tp = type_list; tp; tp = tp->tp_next)
fprintf(f, "%s alloc'd: %" PY_FORMAT_SIZE_T "d, "
"freed: %" PY_FORMAT_SIZE_T "d, "
"max in use: %" PY_FORMAT_SIZE_T "d\n",
tp->tp_name, tp->tp_allocs, tp->tp_frees,
tp->tp_maxalloc);
fprintf(f, "fast tuple allocs: %" PY_FORMAT_SIZE_T "d, "
"empty: %" PY_FORMAT_SIZE_T "d\n",
fast_tuple_allocs, tuple_zero_allocs);
fprintf(f, "fast int allocs: pos: %" PY_FORMAT_SIZE_T "d, "
"neg: %" PY_FORMAT_SIZE_T "d\n",
quick_int_allocs, quick_neg_int_allocs);
fprintf(f, "null strings: %" PY_FORMAT_SIZE_T "d, "
"1-strings: %" PY_FORMAT_SIZE_T "d\n",
null_strings, one_strings);
}
PyObject *
get_counts(void)
{
PyTypeObject *tp;
PyObject *result;
PyObject *v;
result = PyList_New(0);
if (result == NULL)
return NULL;
for (tp = type_list; tp; tp = tp->tp_next) {
v = Py_BuildValue("(snnn)", tp->tp_name, tp->tp_allocs,
tp->tp_frees, tp->tp_maxalloc);
if (v == NULL) {
Py_DECREF(result);
return NULL;
}
if (PyList_Append(result, v) < 0) {
Py_DECREF(v);
Py_DECREF(result);
return NULL;
}
Py_DECREF(v);
}
return result;
}
void
inc_count(PyTypeObject *tp)
{
if (tp->tp_next == NULL && tp->tp_prev == NULL) {
/* first time; insert in linked list */
if (tp->tp_next != NULL) /* sanity check */
Py_FatalError("XXX inc_count sanity check");
if (type_list)
type_list->tp_prev = tp;
tp->tp_next = type_list;
/* Note that as of Python 2.2, heap-allocated type objects
* can go away, but this code requires that they stay alive
* until program exit. That's why we're careful with
* refcounts here. type_list gets a new reference to tp,
* while ownership of the reference type_list used to hold
* (if any) was transferred to tp->tp_next in the line above.
* tp is thus effectively immortal after this.
*/
Py_INCREF(tp);
type_list = tp;
#ifdef Py_TRACE_REFS
/* Also insert in the doubly-linked list of all objects,
* if not already there.
*/
_Py_AddToAllObjects((PyObject *)tp, 0);
#endif
}
tp->tp_allocs++;
if (tp->tp_allocs - tp->tp_frees > tp->tp_maxalloc)
tp->tp_maxalloc = tp->tp_allocs - tp->tp_frees;
}
void dec_count(PyTypeObject *tp)
{
tp->tp_frees++;
if (unlist_types_without_objects &&
tp->tp_allocs == tp->tp_frees) {
/* unlink the type from type_list */
if (tp->tp_prev)
tp->tp_prev->tp_next = tp->tp_next;
else
type_list = tp->tp_next;
if (tp->tp_next)
tp->tp_next->tp_prev = tp->tp_prev;
tp->tp_next = tp->tp_prev = NULL;
Py_DECREF(tp);
}
}
#endif
#ifdef Py_REF_DEBUG
/* Log a fatal error; doesn't return. */
void
_Py_NegativeRefcount(const char *fname, int lineno, PyObject *op)
{
char buf[300];
PyOS_snprintf(buf, sizeof(buf),
"%s:%i object at %p has negative ref count "
"%" PY_FORMAT_SIZE_T "d",
fname, lineno, op, op->ob_refcnt);
Py_FatalError(buf);
}
#endif /* Py_REF_DEBUG */
void
Py_IncRef(PyObject *o)
{
Py_XINCREF(o);
}
void
Py_DecRef(PyObject *o)
{
Py_XDECREF(o);
}
PyObject *
PyObject_Init(PyObject *op, PyTypeObject *tp)
{
if (op == NULL)
return PyErr_NoMemory();
/* Any changes should be reflected in PyObject_INIT (objimpl.h) */
Py_TYPE(op) = tp;
_Py_NewReference(op);
return op;
}
PyVarObject *
PyObject_InitVar(PyVarObject *op, PyTypeObject *tp, Py_ssize_t size)
{
if (op == NULL)
return (PyVarObject *) PyErr_NoMemory();
/* Any changes should be reflected in PyObject_INIT_VAR */
op->ob_size = size;
Py_TYPE(op) = tp;
_Py_NewReference((PyObject *)op);
return op;
}
PyObject *
_PyObject_New(PyTypeObject *tp)
{
PyObject *op;
op = (PyObject *) PyObject_MALLOC(_PyObject_SIZE(tp));
if (op == NULL)
return PyErr_NoMemory();
return PyObject_INIT(op, tp);
}
PyVarObject *
_PyObject_NewVar(PyTypeObject *tp, Py_ssize_t nitems)
{
PyVarObject *op;
const size_t size = _PyObject_VAR_SIZE(tp, nitems);
op = (PyVarObject *) PyObject_MALLOC(size);
if (op == NULL)
return (PyVarObject *)PyErr_NoMemory();
return PyObject_INIT_VAR(op, tp, nitems);
}
void
PyObject_CallFinalizer(PyObject *self)
{
PyTypeObject *tp = Py_TYPE(self);
/* The former could happen on heaptypes created from the C API, e.g.
PyType_FromSpec(). */
if (!PyType_HasFeature(tp, Py_TPFLAGS_HAVE_FINALIZE) ||
tp->tp_finalize == NULL)
return;
/* tp_finalize should only be called once. */
if (PyType_IS_GC(tp) && _PyGC_FINALIZED(self))
return;
tp->tp_finalize(self);
if (PyType_IS_GC(tp))
_PyGC_SET_FINALIZED(self, 1);
}
int
PyObject_CallFinalizerFromDealloc(PyObject *self)
{
Py_ssize_t refcnt;
/* Temporarily resurrect the object. */
if (self->ob_refcnt != 0) {
Py_FatalError("PyObject_CallFinalizerFromDealloc called on "
"object with a non-zero refcount");
}
self->ob_refcnt = 1;
PyObject_CallFinalizer(self);
/* Undo the temporary resurrection; can't use DECREF here, it would
* cause a recursive call.
*/
assert(self->ob_refcnt > 0);
if (--self->ob_refcnt == 0)
return 0; /* this is the normal path out */
/* tp_finalize resurrected it! Make it look like the original Py_DECREF
* never happened.
*/
refcnt = self->ob_refcnt;
_Py_NewReference(self);
self->ob_refcnt = refcnt;
if (PyType_IS_GC(Py_TYPE(self))) {
assert(_PyGC_REFS(self) != _PyGC_REFS_UNTRACKED);
}
/* If Py_REF_DEBUG, _Py_NewReference bumped _Py_RefTotal, so
* we need to undo that. */
_Py_DEC_REFTOTAL;
/* If Py_TRACE_REFS, _Py_NewReference re-added self to the object
* chain, so no more to do there.
* If COUNT_ALLOCS, the original decref bumped tp_frees, and
* _Py_NewReference bumped tp_allocs: both of those need to be
* undone.
*/
#ifdef COUNT_ALLOCS
--Py_TYPE(self)->tp_frees;
--Py_TYPE(self)->tp_allocs;
#endif
return -1;
}
int
PyObject_Print(PyObject *op, FILE *fp, int flags)
{
int ret = 0;
if (PyErr_CheckSignals())
return -1;
#ifdef USE_STACKCHECK
if (PyOS_CheckStack()) {
PyErr_SetString(PyExc_MemoryError, "stack overflow");
return -1;
}
#endif
clearerr(fp); /* Clear any previous error condition */
if (op == NULL) {
Py_BEGIN_ALLOW_THREADS
fprintf(fp, "<nil>");
Py_END_ALLOW_THREADS
}
else {
if (op->ob_refcnt <= 0)
/* XXX(twouters) cast refcount to long until %zd is
universally available */
Py_BEGIN_ALLOW_THREADS
fprintf(fp, "<refcnt %ld at %p>",
(long)op->ob_refcnt, op);
Py_END_ALLOW_THREADS
else {
PyObject *s;
if (flags & Py_PRINT_RAW)
s = PyObject_Str(op);
else
s = PyObject_Repr(op);
if (s == NULL)
ret = -1;
else if (PyBytes_Check(s)) {
fwrite(PyBytes_AS_STRING(s), 1,
PyBytes_GET_SIZE(s), fp);
}
else if (PyUnicode_Check(s)) {
PyObject *t;
t = PyUnicode_AsEncodedString(s, "utf-8", "backslashreplace");
if (t == NULL) {
ret = -1;
}
else {
fwrite(PyBytes_AS_STRING(t), 1,
PyBytes_GET_SIZE(t), fp);
Py_DECREF(t);
}
}
else {
PyErr_Format(PyExc_TypeError,
"str() or repr() returned '%.100s'",
s->ob_type->tp_name);
ret = -1;
}
Py_XDECREF(s);
}
}
if (ret == 0) {
if (ferror(fp)) {
PyErr_SetFromErrno(PyExc_IOError);
clearerr(fp);
ret = -1;
}
}
return ret;
}
/* For debugging convenience. Set a breakpoint here and call it from your DLL */
void
_Py_BreakPoint(void)
{
}
/* Heuristic checking if the object memory has been deallocated.
Rely on the debug hooks on Python memory allocators which fills the memory
with DEADBYTE (0xDB) when memory is deallocated.
The function can be used to prevent segmentation fault on dereferencing
pointers like 0xdbdbdbdbdbdbdbdb. Such pointer is very unlikely to be mapped
in memory. */
int
_PyObject_IsFreed(PyObject *op)
{
uintptr_t ptr = (uintptr_t)op;
if (_PyMem_IsFreed(&ptr, sizeof(ptr))) {
return 1;
}
int freed = _PyMem_IsFreed(&op->ob_type, sizeof(op->ob_type));
/* ignore op->ob_ref: the value can have be modified
by Py_INCREF() and Py_DECREF(). */
#ifdef Py_TRACE_REFS
freed &= _PyMem_IsFreed(&op->_ob_next, sizeof(op->_ob_next));
freed &= _PyMem_IsFreed(&op->_ob_prev, sizeof(op->_ob_prev));
#endif
return freed;
}
/* For debugging convenience. See Misc/gdbinit for some useful gdb hooks */
void
_PyObject_Dump(PyObject* op)
{
if (op == NULL) {
fprintf(stderr, "<NULL object>\n");
fflush(stderr);
return;
}
if (_PyObject_IsFreed(op)) {
/* It seems like the object memory has been freed:
don't access it to prevent a segmentation fault. */
fprintf(stderr, "<freed object>\n");
return;
}
PyGILState_STATE gil;
PyObject *error_type, *error_value, *error_traceback;
fprintf(stderr, "object : ");
fflush(stderr);
gil = PyGILState_Ensure();
PyErr_Fetch(&error_type, &error_value, &error_traceback);
(void)PyObject_Print(op, stderr, 0);
fflush(stderr);
PyErr_Restore(error_type, error_value, error_traceback);
PyGILState_Release(gil);
/* XXX(twouters) cast refcount to long until %zd is
universally available */
fprintf(stderr, "\n"
"type : %s\n"
"refcount: %ld\n"
"address : %p\n",
Py_TYPE(op)==NULL ? "NULL" : Py_TYPE(op)->tp_name,
(long)op->ob_refcnt,
op);
fflush(stderr);
}
PyObject *
PyObject_Repr(PyObject *v)
{
PyObject *res;
if (PyErr_CheckSignals())
return NULL;
#ifdef USE_STACKCHECK
if (PyOS_CheckStack()) {
PyErr_SetString(PyExc_MemoryError, "stack overflow");
return NULL;
}
#endif
if (v == NULL)
return PyUnicode_FromString("<NULL>");
if (Py_TYPE(v)->tp_repr == NULL)
return PyUnicode_FromFormat("<%s object at %p>",
v->ob_type->tp_name, v);
#ifdef Py_DEBUG
/* PyObject_Repr() must not be called with an exception set,
because it may clear it (directly or indirectly) and so the
caller loses its exception */
assert(!PyErr_Occurred());
#endif
/* It is possible for a type to have a tp_repr representation that loops
infinitely. */
if (Py_EnterRecursiveCall(" while getting the repr of an object"))
return NULL;
res = (*v->ob_type->tp_repr)(v);
Py_LeaveRecursiveCall();
if (res == NULL)
return NULL;
if (!PyUnicode_Check(res)) {
PyErr_Format(PyExc_TypeError,
"__repr__ returned non-string (type %.200s)",
res->ob_type->tp_name);
Py_DECREF(res);
return NULL;
}
#ifndef Py_DEBUG
if (PyUnicode_READY(res) < 0)
return NULL;
#endif
return res;
}
PyObject *
PyObject_Str(PyObject *v)
{
PyObject *res;
if (PyErr_CheckSignals())
return NULL;
#ifdef USE_STACKCHECK
if (PyOS_CheckStack()) {
PyErr_SetString(PyExc_MemoryError, "stack overflow");
return NULL;
}
#endif
if (v == NULL)
return PyUnicode_FromString("<NULL>");
if (PyUnicode_CheckExact(v)) {
#ifndef Py_DEBUG
if (PyUnicode_READY(v) < 0)
return NULL;
#endif
Py_INCREF(v);
return v;
}
if (Py_TYPE(v)->tp_str == NULL)
return PyObject_Repr(v);
#ifdef Py_DEBUG
/* PyObject_Str() must not be called with an exception set,
because it may clear it (directly or indirectly) and so the
caller loses its exception */
assert(!PyErr_Occurred());
#endif
/* It is possible for a type to have a tp_str representation that loops
infinitely. */
if (Py_EnterRecursiveCall(" while getting the str of an object"))
return NULL;
res = (*Py_TYPE(v)->tp_str)(v);
Py_LeaveRecursiveCall();
if (res == NULL)
return NULL;
if (!PyUnicode_Check(res)) {
PyErr_Format(PyExc_TypeError,
"__str__ returned non-string (type %.200s)",
Py_TYPE(res)->tp_name);
Py_DECREF(res);
return NULL;
}
#ifndef Py_DEBUG
if (PyUnicode_READY(res) < 0)
return NULL;
#endif
assert(_PyUnicode_CheckConsistency(res, 1));
return res;
}
PyObject *
PyObject_ASCII(PyObject *v)
{
PyObject *repr, *ascii, *res;
repr = PyObject_Repr(v);
if (repr == NULL)
return NULL;
if (PyUnicode_IS_ASCII(repr))
return repr;
/* repr is guaranteed to be a PyUnicode object by PyObject_Repr */
ascii = _PyUnicode_AsASCIIString(repr, "backslashreplace");
Py_DECREF(repr);
if (ascii == NULL)
return NULL;
res = PyUnicode_DecodeASCII(
PyBytes_AS_STRING(ascii),
PyBytes_GET_SIZE(ascii),
NULL);
Py_DECREF(ascii);
return res;
}
PyObject *
PyObject_Bytes(PyObject *v)
{
PyObject *result, *func;
if (v == NULL)
return PyBytes_FromString("<NULL>");
if (PyBytes_CheckExact(v)) {
Py_INCREF(v);
return v;
}
func = _PyObject_LookupSpecial(v, &PyId___bytes__);
if (func != NULL) {
result = PyObject_CallFunctionObjArgs(func, NULL);
Py_DECREF(func);
if (result == NULL)
return NULL;
if (!PyBytes_Check(result)) {
PyErr_Format(PyExc_TypeError,
"__bytes__ returned non-bytes (type %.200s)",
Py_TYPE(result)->tp_name);
Py_DECREF(result);
return NULL;
}
return result;
}
else if (PyErr_Occurred())
return NULL;
return PyBytes_FromObject(v);
}
/* For Python 3.0.1 and later, the old three-way comparison has been
completely removed in favour of rich comparisons. PyObject_Compare() and
PyObject_Cmp() are gone, and the builtin cmp function no longer exists.
The old tp_compare slot has been renamed to tp_reserved, and should no
longer be used. Use tp_richcompare instead.
See (*) below for practical amendments.
tp_richcompare gets called with a first argument of the appropriate type
and a second object of an arbitrary type. We never do any kind of
coercion.
The tp_richcompare slot should return an object, as follows:
NULL if an exception occurred
NotImplemented if the requested comparison is not implemented
any other false value if the requested comparison is false
any other true value if the requested comparison is true
The PyObject_RichCompare[Bool]() wrappers raise TypeError when they get
NotImplemented.
(*) Practical amendments:
- If rich comparison returns NotImplemented, == and != are decided by
comparing the object pointer (i.e. falling back to the base object
implementation).
*/
/* Map rich comparison operators to their swapped version, e.g. LT <--> GT */
int _Py_SwappedOp[] = {Py_GT, Py_GE, Py_EQ, Py_NE, Py_LT, Py_LE};
static const char * const opstrings[] = {"<", "<=", "==", "!=", ">", ">="};
/* Perform a rich comparison, raising TypeError when the requested comparison
operator is not supported. */
static PyObject *
do_richcompare(PyObject *v, PyObject *w, int op)
{
richcmpfunc f;
PyObject *res;
int checked_reverse_op = 0;
if (v->ob_type != w->ob_type &&
PyType_IsSubtype(w->ob_type, v->ob_type) &&
(f = w->ob_type->tp_richcompare) != NULL) {
checked_reverse_op = 1;
res = (*f)(w, v, _Py_SwappedOp[op]);
if (res != Py_NotImplemented)
return res;
Py_DECREF(res);
}
if ((f = v->ob_type->tp_richcompare) != NULL) {
res = (*f)(v, w, op);
if (res != Py_NotImplemented)
return res;
Py_DECREF(res);
}
if (!checked_reverse_op && (f = w->ob_type->tp_richcompare) != NULL) {
res = (*f)(w, v, _Py_SwappedOp[op]);
if (res != Py_NotImplemented)
return res;
Py_DECREF(res);
}
/* If neither object implements it, provide a sensible default
for == and !=, but raise an exception for ordering. */
switch (op) {
case Py_EQ:
res = (v == w) ? Py_True : Py_False;
break;
case Py_NE:
res = (v != w) ? Py_True : Py_False;
break;
default:
PyErr_Format(PyExc_TypeError,
"'%s' not supported between instances of '%.100s' and '%.100s'",
opstrings[op],
v->ob_type->tp_name,
w->ob_type->tp_name);
return NULL;
}
Py_INCREF(res);
return res;
}
/* Perform a rich comparison with object result. This wraps do_richcompare()
with a check for NULL arguments and a recursion check. */
PyObject *
PyObject_RichCompare(PyObject *v, PyObject *w, int op)
{
PyObject *res;
assert(Py_LT <= op && op <= Py_GE);
if (v == NULL || w == NULL) {
if (!PyErr_Occurred())
PyErr_BadInternalCall();
return NULL;
}
if (Py_EnterRecursiveCall(" in comparison"))
return NULL;
res = do_richcompare(v, w, op);
Py_LeaveRecursiveCall();
return res;
}
/* Perform a rich comparison with integer result. This wraps
PyObject_RichCompare(), returning -1 for error, 0 for false, 1 for true. */
int
PyObject_RichCompareBool(PyObject *v, PyObject *w, int op)
{
PyObject *res;
int ok;
/* Quick result when objects are the same.
Guarantees that identity implies equality. */
if (v == w) {
if (op == Py_EQ)
return 1;
else if (op == Py_NE)
return 0;
}
res = PyObject_RichCompare(v, w, op);
if (res == NULL)
return -1;
if (PyBool_Check(res))
ok = (res == Py_True);
else
ok = PyObject_IsTrue(res);
Py_DECREF(res);
return ok;
}
Py_hash_t
PyObject_HashNotImplemented(PyObject *v)
{
PyErr_Format(PyExc_TypeError, "unhashable type: '%.200s'",
Py_TYPE(v)->tp_name);
return -1;
}
Py_hash_t
PyObject_Hash(PyObject *v)
{
PyTypeObject *tp = Py_TYPE(v);
if (tp->tp_hash != NULL)
return (*tp->tp_hash)(v);
/* To keep to the general practice that inheriting
* solely from object in C code should work without
* an explicit call to PyType_Ready, we implicitly call
* PyType_Ready here and then check the tp_hash slot again
*/
if (tp->tp_dict == NULL) {
if (PyType_Ready(tp) < 0)
return -1;
if (tp->tp_hash != NULL)
return (*tp->tp_hash)(v);
}
/* Otherwise, the object can't be hashed */
return PyObject_HashNotImplemented(v);
}
PyObject *
PyObject_GetAttrString(PyObject *v, const char *name)
{
PyObject *w, *res;
if (Py_TYPE(v)->tp_getattr != NULL)
return (*Py_TYPE(v)->tp_getattr)(v, (char*)name);
w = PyUnicode_InternFromString(name);
if (w == NULL)
return NULL;
res = PyObject_GetAttr(v, w);
Py_DECREF(w);
return res;
}
int
PyObject_HasAttrString(PyObject *v, const char *name)
{
PyObject *res = PyObject_GetAttrString(v, name);
if (res != NULL) {
Py_DECREF(res);
return 1;
}
PyErr_Clear();
return 0;
}
int
PyObject_SetAttrString(PyObject *v, const char *name, PyObject *w)
{
PyObject *s;
int res;
if (Py_TYPE(v)->tp_setattr != NULL)
return (*Py_TYPE(v)->tp_setattr)(v, (char*)name, w);
s = PyUnicode_InternFromString(name);
if (s == NULL)
return -1;
res = PyObject_SetAttr(v, s, w);
Py_XDECREF(s);
return res;
}
int
_PyObject_IsAbstract(PyObject *obj)
{
int res;
PyObject* isabstract;
if (obj == NULL)
return 0;
isabstract = _PyObject_GetAttrId(obj, &PyId___isabstractmethod__);
if (isabstract == NULL) {
if (PyErr_ExceptionMatches(PyExc_AttributeError)) {
PyErr_Clear();
return 0;
}
return -1;
}
res = PyObject_IsTrue(isabstract);
Py_DECREF(isabstract);
return res;
}
PyObject *
_PyObject_GetAttrId(PyObject *v, _Py_Identifier *name)
{
PyObject *result;
PyObject *oname = _PyUnicode_FromId(name); /* borrowed */
if (!oname)
return NULL;
result = PyObject_GetAttr(v, oname);
return result;
}
int
_PyObject_HasAttrId(PyObject *v, _Py_Identifier *name)
{
int result;
PyObject *oname = _PyUnicode_FromId(name); /* borrowed */
if (!oname)
return -1;
result = PyObject_HasAttr(v, oname);
return result;
}
int
_PyObject_SetAttrId(PyObject *v, _Py_Identifier *name, PyObject *w)
{
int result;
PyObject *oname = _PyUnicode_FromId(name); /* borrowed */
if (!oname)
return -1;
result = PyObject_SetAttr(v, oname, w);
return result;
}
PyObject *
PyObject_GetAttr(PyObject *v, PyObject *name)
{
PyTypeObject *tp = Py_TYPE(v);
if (!PyUnicode_Check(name)) {
PyErr_Format(PyExc_TypeError,
"attribute name must be string, not '%.200s'",
name->ob_type->tp_name);
return NULL;
}
if (tp->tp_getattro != NULL)
return (*tp->tp_getattro)(v, name);
if (tp->tp_getattr != NULL) {
char *name_str = PyUnicode_AsUTF8(name);
if (name_str == NULL)
return NULL;
return (*tp->tp_getattr)(v, name_str);
}
PyErr_Format(PyExc_AttributeError,
"'%.50s' object has no attribute '%U'",
tp->tp_name, name);
return NULL;
}
int
PyObject_HasAttr(PyObject *v, PyObject *name)
{
PyObject *res = PyObject_GetAttr(v, name);
if (res != NULL) {
Py_DECREF(res);
return 1;
}
PyErr_Clear();
return 0;
}
int
PyObject_SetAttr(PyObject *v, PyObject *name, PyObject *value)
{
PyTypeObject *tp = Py_TYPE(v);
int err;
if (!PyUnicode_Check(name)) {
PyErr_Format(PyExc_TypeError,
"attribute name must be string, not '%.200s'",
name->ob_type->tp_name);
return -1;
}
Py_INCREF(name);
PyUnicode_InternInPlace(&name);
if (tp->tp_setattro != NULL) {
err = (*tp->tp_setattro)(v, name, value);
Py_DECREF(name);
return err;
}
if (tp->tp_setattr != NULL) {
char *name_str = PyUnicode_AsUTF8(name);
if (name_str == NULL)
return -1;
err = (*tp->tp_setattr)(v, name_str, value);
Py_DECREF(name);
return err;
}
Py_DECREF(name);
assert(name->ob_refcnt >= 1);
if (tp->tp_getattr == NULL && tp->tp_getattro == NULL)
PyErr_Format(PyExc_TypeError,
"'%.100s' object has no attributes "
"(%s .%U)",
tp->tp_name,
value==NULL ? "del" : "assign to",
name);
else
PyErr_Format(PyExc_TypeError,
"'%.100s' object has only read-only attributes "
"(%s .%U)",
tp->tp_name,
value==NULL ? "del" : "assign to",
name);
return -1;
}
/* Helper to get a pointer to an object's __dict__ slot, if any */