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object.c
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2314 lines (2082 loc) · 54 KB
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/* Generic object operations; and implementation of None (NoObject) */
#include "Python.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifdef Py_REF_DEBUG
Py_ssize_t _Py_RefTotal;
Py_ssize_t
_Py_GetRefTotal(void)
{
PyObject *o;
Py_ssize_t total = _Py_RefTotal;
/* ignore the references to the dummy object of the dicts and sets
because they are not reliable and not useful (now that the
hash table code is well-tested) */
o = _PyDict_Dummy();
if (o != NULL)
total -= o->ob_refcnt;
o = _PySet_Dummy();
if (o != NULL)
total -= o->ob_refcnt;
return total;
}
#endif /* Py_REF_DEBUG */
int Py_DivisionWarningFlag;
int Py_Py3kWarningFlag;
/* 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;
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);
}
/* for binary compatibility with 2.2 */
#undef _PyObject_Del
void
_PyObject_Del(PyObject *op)
{
PyObject_FREE(op);
}
/* Implementation of PyObject_Print with recursion checking */
static int
internal_print(PyObject *op, FILE *fp, int flags, int nesting)
{
int ret = 0;
if (nesting > 10) {
PyErr_SetString(PyExc_RuntimeError, "print recursion");
return -1;
}
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 if (Py_TYPE(op)->tp_print == NULL) {
PyObject *s;
if (flags & Py_PRINT_RAW)
s = PyObject_Str(op);
else
s = PyObject_Repr(op);
if (s == NULL)
ret = -1;
else {
ret = internal_print(s, fp, Py_PRINT_RAW,
nesting+1);
}
Py_XDECREF(s);
}
else
ret = (*Py_TYPE(op)->tp_print)(op, fp, flags);
}
if (ret == 0) {
if (ferror(fp)) {
PyErr_SetFromErrno(PyExc_IOError);
clearerr(fp);
ret = -1;
}
}
return ret;
}
int
PyObject_Print(PyObject *op, FILE *fp, int flags)
{
return internal_print(op, fp, flags, 0);
}
/* For debugging convenience. See Misc/gdbinit for some useful gdb hooks */
void _PyObject_Dump(PyObject* op)
{
if (op == NULL)
fprintf(stderr, "NULL\n");
else {
PyGILState_STATE gil;
fprintf(stderr, "object : ");
gil = PyGILState_Ensure();
(void)PyObject_Print(op, stderr, 0);
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);
}
}
PyObject *
PyObject_Repr(PyObject *v)
{
if (PyErr_CheckSignals())
return NULL;
#ifdef USE_STACKCHECK
if (PyOS_CheckStack()) {
PyErr_SetString(PyExc_MemoryError, "stack overflow");
return NULL;
}
#endif
if (v == NULL)
return PyString_FromString("<NULL>");
else if (Py_TYPE(v)->tp_repr == NULL)
return PyString_FromFormat("<%s object at %p>",
Py_TYPE(v)->tp_name, v);
else {
PyObject *res;
res = (*Py_TYPE(v)->tp_repr)(v);
if (res == NULL)
return NULL;
#ifdef Py_USING_UNICODE
if (PyUnicode_Check(res)) {
PyObject* str;
str = PyUnicode_AsEncodedString(res, NULL, NULL);
Py_DECREF(res);
if (str)
res = str;
else
return NULL;
}
#endif
if (!PyString_Check(res)) {
PyErr_Format(PyExc_TypeError,
"__repr__ returned non-string (type %.200s)",
Py_TYPE(res)->tp_name);
Py_DECREF(res);
return NULL;
}
return res;
}
}
PyObject *
_PyObject_Str(PyObject *v)
{
PyObject *res;
int type_ok;
if (v == NULL)
return PyString_FromString("<NULL>");
if (PyString_CheckExact(v)) {
Py_INCREF(v);
return v;
}
#ifdef Py_USING_UNICODE
if (PyUnicode_CheckExact(v)) {
Py_INCREF(v);
return v;
}
#endif
if (Py_TYPE(v)->tp_str == NULL)
return PyObject_Repr(v);
/* 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;
type_ok = PyString_Check(res);
#ifdef Py_USING_UNICODE
type_ok = type_ok || PyUnicode_Check(res);
#endif
if (!type_ok) {
PyErr_Format(PyExc_TypeError,
"__str__ returned non-string (type %.200s)",
Py_TYPE(res)->tp_name);
Py_DECREF(res);
return NULL;
}
return res;
}
PyObject *
PyObject_Str(PyObject *v)
{
PyObject *res = _PyObject_Str(v);
if (res == NULL)
return NULL;
#ifdef Py_USING_UNICODE
if (PyUnicode_Check(res)) {
PyObject* str;
str = PyUnicode_AsEncodedString(res, NULL, NULL);
Py_DECREF(res);
if (str)
res = str;
else
return NULL;
}
#endif
assert(PyString_Check(res));
return res;
}
#ifdef Py_USING_UNICODE
PyObject *
PyObject_Unicode(PyObject *v)
{
PyObject *res;
PyObject *func;
PyObject *str;
int unicode_method_found = 0;
static PyObject *unicodestr;
if (v == NULL) {
res = PyString_FromString("<NULL>");
if (res == NULL)
return NULL;
str = PyUnicode_FromEncodedObject(res, NULL, "strict");
Py_DECREF(res);
return str;
} else if (PyUnicode_CheckExact(v)) {
Py_INCREF(v);
return v;
}
/* Try the __unicode__ method */
if (unicodestr == NULL) {
unicodestr= PyString_InternFromString("__unicode__");
if (unicodestr == NULL)
return NULL;
}
if (PyInstance_Check(v)) {
/* We're an instance of a classic class */
/* Try __unicode__ from the instance -- alas we have no type */
func = PyObject_GetAttr(v, unicodestr);
if (func != NULL) {
unicode_method_found = 1;
res = PyObject_CallFunctionObjArgs(func, NULL);
Py_DECREF(func);
}
else {
PyErr_Clear();
}
}
else {
/* Not a classic class instance, try __unicode__ from type */
/* _PyType_Lookup doesn't create a reference */
func = _PyType_Lookup(Py_TYPE(v), unicodestr);
if (func != NULL) {
unicode_method_found = 1;
res = PyObject_CallFunctionObjArgs(func, v, NULL);
}
else {
PyErr_Clear();
}
}
/* Didn't find __unicode__ */
if (!unicode_method_found) {
if (PyUnicode_Check(v)) {
/* For a Unicode subtype that's didn't overwrite __unicode__,
return a true Unicode object with the same data. */
return PyUnicode_FromUnicode(PyUnicode_AS_UNICODE(v),
PyUnicode_GET_SIZE(v));
}
if (PyString_CheckExact(v)) {
Py_INCREF(v);
res = v;
}
else {
if (Py_TYPE(v)->tp_str != NULL)
res = (*Py_TYPE(v)->tp_str)(v);
else
res = PyObject_Repr(v);
}
}
if (res == NULL)
return NULL;
if (!PyUnicode_Check(res)) {
str = PyUnicode_FromEncodedObject(res, NULL, "strict");
Py_DECREF(res);
res = str;
}
return res;
}
#endif
/* Helper to warn about deprecated tp_compare return values. Return:
-2 for an exception;
-1 if v < w;
0 if v == w;
1 if v > w.
(This function cannot return 2.)
*/
static int
adjust_tp_compare(int c)
{
if (PyErr_Occurred()) {
if (c != -1 && c != -2) {
PyObject *t, *v, *tb;
PyErr_Fetch(&t, &v, &tb);
if (PyErr_Warn(PyExc_RuntimeWarning,
"tp_compare didn't return -1 or -2 "
"for exception") < 0) {
Py_XDECREF(t);
Py_XDECREF(v);
Py_XDECREF(tb);
}
else
PyErr_Restore(t, v, tb);
}
return -2;
}
else if (c < -1 || c > 1) {
if (PyErr_Warn(PyExc_RuntimeWarning,
"tp_compare didn't return -1, 0 or 1") < 0)
return -2;
else
return c < -1 ? -1 : 1;
}
else {
assert(c >= -1 && c <= 1);
return c;
}
}
/* Macro to get the tp_richcompare field of a type if defined */
#define RICHCOMPARE(t) (PyType_HasFeature((t), Py_TPFLAGS_HAVE_RICHCOMPARE) \
? (t)->tp_richcompare : NULL)
/* 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};
/* Try a genuine rich comparison, returning an object. Return:
NULL for exception;
NotImplemented if this particular rich comparison is not implemented or
undefined;
some object not equal to NotImplemented if it is implemented
(this latter object may not be a Boolean).
*/
static PyObject *
try_rich_compare(PyObject *v, PyObject *w, int op)
{
richcmpfunc f;
PyObject *res;
if (v->ob_type != w->ob_type &&
PyType_IsSubtype(w->ob_type, v->ob_type) &&
(f = RICHCOMPARE(w->ob_type)) != NULL) {
res = (*f)(w, v, _Py_SwappedOp[op]);
if (res != Py_NotImplemented)
return res;
Py_DECREF(res);
}
if ((f = RICHCOMPARE(v->ob_type)) != NULL) {
res = (*f)(v, w, op);
if (res != Py_NotImplemented)
return res;
Py_DECREF(res);
}
if ((f = RICHCOMPARE(w->ob_type)) != NULL) {
return (*f)(w, v, _Py_SwappedOp[op]);
}
res = Py_NotImplemented;
Py_INCREF(res);
return res;
}
/* Try a genuine rich comparison, returning an int. Return:
-1 for exception (including the case where try_rich_compare() returns an
object that's not a Boolean);
0 if the outcome is false;
1 if the outcome is true;
2 if this particular rich comparison is not implemented or undefined.
*/
static int
try_rich_compare_bool(PyObject *v, PyObject *w, int op)
{
PyObject *res;
int ok;
if (RICHCOMPARE(v->ob_type) == NULL && RICHCOMPARE(w->ob_type) == NULL)
return 2; /* Shortcut, avoid INCREF+DECREF */
res = try_rich_compare(v, w, op);
if (res == NULL)
return -1;
if (res == Py_NotImplemented) {
Py_DECREF(res);
return 2;
}
ok = PyObject_IsTrue(res);
Py_DECREF(res);
return ok;
}
/* Try rich comparisons to determine a 3-way comparison. Return:
-2 for an exception;
-1 if v < w;
0 if v == w;
1 if v > w;
2 if this particular rich comparison is not implemented or undefined.
*/
static int
try_rich_to_3way_compare(PyObject *v, PyObject *w)
{
static struct { int op; int outcome; } tries[3] = {
/* Try this operator, and if it is true, use this outcome: */
{Py_EQ, 0},
{Py_LT, -1},
{Py_GT, 1},
};
int i;
if (RICHCOMPARE(v->ob_type) == NULL && RICHCOMPARE(w->ob_type) == NULL)
return 2; /* Shortcut */
for (i = 0; i < 3; i++) {
switch (try_rich_compare_bool(v, w, tries[i].op)) {
case -1:
return -2;
case 1:
return tries[i].outcome;
}
}
return 2;
}
/* Try a 3-way comparison, returning an int. Return:
-2 for an exception;
-1 if v < w;
0 if v == w;
1 if v > w;
2 if this particular 3-way comparison is not implemented or undefined.
*/
static int
try_3way_compare(PyObject *v, PyObject *w)
{
int c;
cmpfunc f;
/* Comparisons involving instances are given to instance_compare,
which has the same return conventions as this function. */
f = v->ob_type->tp_compare;
if (PyInstance_Check(v))
return (*f)(v, w);
if (PyInstance_Check(w))
return (*w->ob_type->tp_compare)(v, w);
/* If both have the same (non-NULL) tp_compare, use it. */
if (f != NULL && f == w->ob_type->tp_compare) {
c = (*f)(v, w);
return adjust_tp_compare(c);
}
/* If either tp_compare is _PyObject_SlotCompare, that's safe. */
if (f == _PyObject_SlotCompare ||
w->ob_type->tp_compare == _PyObject_SlotCompare)
return _PyObject_SlotCompare(v, w);
/* If we're here, v and w,
a) are not instances;
b) have different types or a type without tp_compare; and
c) don't have a user-defined tp_compare.
tp_compare implementations in C assume that both arguments
have their type, so we give up if the coercion fails or if
it yields types which are still incompatible (which can
happen with a user-defined nb_coerce).
*/
c = PyNumber_CoerceEx(&v, &w);
if (c < 0)
return -2;
if (c > 0)
return 2;
f = v->ob_type->tp_compare;
if (f != NULL && f == w->ob_type->tp_compare) {
c = (*f)(v, w);
Py_DECREF(v);
Py_DECREF(w);
return adjust_tp_compare(c);
}
/* No comparison defined */
Py_DECREF(v);
Py_DECREF(w);
return 2;
}
/* Final fallback 3-way comparison, returning an int. Return:
-2 if an error occurred;
-1 if v < w;
0 if v == w;
1 if v > w.
*/
static int
default_3way_compare(PyObject *v, PyObject *w)
{
int c;
const char *vname, *wname;
if (v->ob_type == w->ob_type) {
/* When comparing these pointers, they must be cast to
* integer types (i.e. Py_uintptr_t, our spelling of C9X's
* uintptr_t). ANSI specifies that pointer compares other
* than == and != to non-related structures are undefined.
*/
Py_uintptr_t vv = (Py_uintptr_t)v;
Py_uintptr_t ww = (Py_uintptr_t)w;
return (vv < ww) ? -1 : (vv > ww) ? 1 : 0;
}
/* None is smaller than anything */
if (v == Py_None)
return -1;
if (w == Py_None)
return 1;
/* different type: compare type names; numbers are smaller */
if (PyNumber_Check(v))
vname = "";
else
vname = v->ob_type->tp_name;
if (PyNumber_Check(w))
wname = "";
else
wname = w->ob_type->tp_name;
c = strcmp(vname, wname);
if (c < 0)
return -1;
if (c > 0)
return 1;
/* Same type name, or (more likely) incomparable numeric types */
return ((Py_uintptr_t)(v->ob_type) < (
Py_uintptr_t)(w->ob_type)) ? -1 : 1;
}
/* Do a 3-way comparison, by hook or by crook. Return:
-2 for an exception (but see below);
-1 if v < w;
0 if v == w;
1 if v > w;
BUT: if the object implements a tp_compare function, it returns
whatever this function returns (whether with an exception or not).
*/
static int
do_cmp(PyObject *v, PyObject *w)
{
int c;
cmpfunc f;
if (v->ob_type == w->ob_type
&& (f = v->ob_type->tp_compare) != NULL) {
c = (*f)(v, w);
if (PyInstance_Check(v)) {
/* Instance tp_compare has a different signature.
But if it returns undefined we fall through. */
if (c != 2)
return c;
/* Else fall through to try_rich_to_3way_compare() */
}
else
return adjust_tp_compare(c);
}
/* We only get here if one of the following is true:
a) v and w have different types
b) v and w have the same type, which doesn't have tp_compare
c) v and w are instances, and either __cmp__ is not defined or
__cmp__ returns NotImplemented
*/
c = try_rich_to_3way_compare(v, w);
if (c < 2)
return c;
c = try_3way_compare(v, w);
if (c < 2)
return c;
return default_3way_compare(v, w);
}
/* Compare v to w. Return
-1 if v < w or exception (PyErr_Occurred() true in latter case).
0 if v == w.
1 if v > w.
XXX The docs (C API manual) say the return value is undefined in case
XXX of error.
*/
int
PyObject_Compare(PyObject *v, PyObject *w)
{
int result;
if (v == NULL || w == NULL) {
PyErr_BadInternalCall();
return -1;
}
if (v == w)
return 0;
if (Py_EnterRecursiveCall(" in cmp"))
return -1;
result = do_cmp(v, w);
Py_LeaveRecursiveCall();
return result < 0 ? -1 : result;
}
/* Return (new reference to) Py_True or Py_False. */
static PyObject *
convert_3way_to_object(int op, int c)
{
PyObject *result;
switch (op) {
case Py_LT: c = c < 0; break;
case Py_LE: c = c <= 0; break;
case Py_EQ: c = c == 0; break;
case Py_NE: c = c != 0; break;
case Py_GT: c = c > 0; break;
case Py_GE: c = c >= 0; break;
}
result = c ? Py_True : Py_False;
Py_INCREF(result);
return result;
}
/* We want a rich comparison but don't have one. Try a 3-way cmp instead.
Return
NULL if error
Py_True if v op w
Py_False if not (v op w)
*/
static PyObject *
try_3way_to_rich_compare(PyObject *v, PyObject *w, int op)
{
int c;
c = try_3way_compare(v, w);
if (c >= 2) {
/* Py3K warning if types are not equal and comparison isn't == or != */
if (Py_Py3kWarningFlag &&
v->ob_type != w->ob_type && op != Py_EQ && op != Py_NE &&
PyErr_WarnEx(PyExc_DeprecationWarning,
"comparing unequal types not supported "
"in 3.x", 1) < 0) {
return NULL;
}
c = default_3way_compare(v, w);
}
if (c <= -2)
return NULL;
return convert_3way_to_object(op, c);
}
/* Do rich comparison on v and w. Return
NULL if error
Else a new reference to an object other than Py_NotImplemented, usually(?):
Py_True if v op w
Py_False if not (v op w)
*/
static PyObject *
do_richcmp(PyObject *v, PyObject *w, int op)
{
PyObject *res;
res = try_rich_compare(v, w, op);
if (res != Py_NotImplemented)
return res;
Py_DECREF(res);
return try_3way_to_rich_compare(v, w, op);
}
/* Return:
NULL for exception;
some object not equal to NotImplemented if it is implemented
(this latter object may not be a Boolean).
*/
PyObject *
PyObject_RichCompare(PyObject *v, PyObject *w, int op)
{
PyObject *res;
assert(Py_LT <= op && op <= Py_GE);
if (Py_EnterRecursiveCall(" in cmp"))
return NULL;
/* If the types are equal, and not old-style instances, try to
get out cheap (don't bother with coercions etc.). */
if (v->ob_type == w->ob_type && !PyInstance_Check(v)) {
cmpfunc fcmp;
richcmpfunc frich = RICHCOMPARE(v->ob_type);
/* If the type has richcmp, try it first. try_rich_compare
tries it two-sided, which is not needed since we've a
single type only. */
if (frich != NULL) {
res = (*frich)(v, w, op);
if (res != Py_NotImplemented)
goto Done;
Py_DECREF(res);
}
/* No richcmp, or this particular richmp not implemented.
Try 3-way cmp. */
fcmp = v->ob_type->tp_compare;
if (fcmp != NULL) {
int c = (*fcmp)(v, w);
c = adjust_tp_compare(c);
if (c == -2) {
res = NULL;
goto Done;
}
res = convert_3way_to_object(op, c);
goto Done;
}
}
/* Fast path not taken, or couldn't deliver a useful result. */
res = do_richcmp(v, w, op);
Done:
Py_LeaveRecursiveCall();
return res;
}
/* Return -1 if error; 1 if v op w; 0 if not (v op w). */
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)