summaryrefslogtreecommitdiffstats
path: root/Objects
diff options
context:
space:
mode:
Diffstat (limited to 'Objects')
-rw-r--r--Objects/dictobject.c157
1 files changed, 107 insertions, 50 deletions
diff --git a/Objects/dictobject.c b/Objects/dictobject.c
index d4cd925..d6b9597 100644
--- a/Objects/dictobject.c
+++ b/Objects/dictobject.c
@@ -241,10 +241,7 @@ lookdict(dictobject *mp, PyObject *key, register long hash)
register Py_ssize_t mask = mp->ma_mask;
dictentry *ep0 = mp->ma_table;
register dictentry *ep;
- register int restore_error;
- register int checked_error;
register int cmp;
- PyObject *err_type, *err_value, *err_tb;
PyObject *startkey;
i = hash & mask;
@@ -252,24 +249,17 @@ lookdict(dictobject *mp, PyObject *key, register long hash)
if (ep->me_key == NULL || ep->me_key == key)
return ep;
- restore_error = checked_error = 0;
if (ep->me_key == dummy)
freeslot = ep;
else {
if (ep->me_hash == hash) {
- /* error can't have been checked yet */
- checked_error = 1;
- if (PyErr_Occurred()) {
- restore_error = 1;
- PyErr_Fetch(&err_type, &err_value, &err_tb);
- }
startkey = ep->me_key;
cmp = PyObject_RichCompareBool(startkey, key, Py_EQ);
if (cmp < 0)
- PyErr_Clear();
+ return NULL;
if (ep0 == mp->ma_table && ep->me_key == startkey) {
if (cmp > 0)
- goto Done;
+ return ep;
}
else {
/* The compare did major nasty stuff to the
@@ -277,8 +267,7 @@ lookdict(dictobject *mp, PyObject *key, register long hash)
* XXX A clever adversary could prevent this
* XXX from terminating.
*/
- ep = lookdict(mp, key, hash);
- goto Done;
+ return lookdict(mp, key, hash);
}
}
freeslot = NULL;
@@ -289,29 +278,18 @@ lookdict(dictobject *mp, PyObject *key, register long hash)
for (perturb = hash; ; perturb >>= PERTURB_SHIFT) {
i = (i << 2) + i + perturb + 1;
ep = &ep0[i & mask];
- if (ep->me_key == NULL) {
- if (freeslot != NULL)
- ep = freeslot;
- break;
- }
+ if (ep->me_key == NULL)
+ return freeslot == NULL ? ep : freeslot;
if (ep->me_key == key)
- break;
+ return ep;
if (ep->me_hash == hash && ep->me_key != dummy) {
- if (!checked_error) {
- checked_error = 1;
- if (PyErr_Occurred()) {
- restore_error = 1;
- PyErr_Fetch(&err_type, &err_value,
- &err_tb);
- }
- }
startkey = ep->me_key;
cmp = PyObject_RichCompareBool(startkey, key, Py_EQ);
if (cmp < 0)
- PyErr_Clear();
+ return NULL;
if (ep0 == mp->ma_table && ep->me_key == startkey) {
if (cmp > 0)
- break;
+ return ep;
}
else {
/* The compare did major nasty stuff to the
@@ -319,18 +297,12 @@ lookdict(dictobject *mp, PyObject *key, register long hash)
* XXX A clever adversary could prevent this
* XXX from terminating.
*/
- ep = lookdict(mp, key, hash);
- break;
+ return lookdict(mp, key, hash);
}
}
else if (ep->me_key == dummy && freeslot == NULL)
freeslot = ep;
}
-
-Done:
- if (restore_error)
- PyErr_Restore(err_type, err_value, err_tb);
- return ep;
}
/*
@@ -400,7 +372,7 @@ Internal routine to insert a new item into the table.
Used both by the internal resize routine and by the public insert routine.
Eats a reference to key and one to value.
*/
-static void
+static int
insertdict(register dictobject *mp, PyObject *key, long hash, PyObject *value)
{
PyObject *old_value;
@@ -409,6 +381,11 @@ insertdict(register dictobject *mp, PyObject *key, long hash, PyObject *value)
assert(mp->ma_lookup != NULL);
ep = mp->ma_lookup(mp, key, hash);
+ if (ep == NULL) {
+ Py_DECREF(key);
+ Py_DECREF(value);
+ return -1;
+ }
if (ep->me_value != NULL) {
old_value = ep->me_value;
ep->me_value = value;
@@ -427,6 +404,36 @@ insertdict(register dictobject *mp, PyObject *key, long hash, PyObject *value)
ep->me_value = value;
mp->ma_used++;
}
+ return 0;
+}
+
+/*
+Internal routine used by dictresize() to insert an item which is
+known to be absent from the dict. This routine also assumes that
+the dict contains no deleted entries. Besides the performance benefit,
+using insertdict() in dictresize() is dangerous (SF bug #1456209).
+*/
+static void
+insertdict_clean(register dictobject *mp, PyObject *key, long hash,
+ PyObject *value)
+{
+ register Py_ssize_t i;
+ register size_t perturb;
+ register unsigned int mask = mp->ma_mask;
+ dictentry *ep0 = mp->ma_table;
+ register dictentry *ep;
+
+ i = hash & mask;
+ ep = &ep0[i];
+ for (perturb = hash; ep->me_key != NULL; perturb >>= PERTURB_SHIFT) {
+ i = (i << 2) + i + perturb + 1;
+ ep = &ep0[i & mask];
+ }
+ mp->ma_fill++;
+ ep->me_key = key;
+ ep->me_hash = (Py_ssize_t)hash;
+ ep->me_value = value;
+ mp->ma_used++;
}
/*
@@ -501,7 +508,8 @@ dictresize(dictobject *mp, Py_ssize_t minused)
for (ep = oldtable; i > 0; ep++) {
if (ep->me_value != NULL) { /* active entry */
--i;
- insertdict(mp, ep->me_key, ep->me_hash, ep->me_value);
+ insertdict_clean(mp, ep->me_key, (long)ep->me_hash,
+ ep->me_value);
}
else if (ep->me_key != NULL) { /* dummy entry */
--i;
@@ -521,6 +529,8 @@ PyDict_GetItem(PyObject *op, PyObject *key)
{
long hash;
dictobject *mp = (dictobject *)op;
+ dictentry *ep;
+ PyThreadState *tstate;
if (!PyDict_Check(op)) {
return NULL;
}
@@ -533,7 +543,29 @@ PyDict_GetItem(PyObject *op, PyObject *key)
return NULL;
}
}
- return (mp->ma_lookup)(mp, key, hash)->me_value;
+
+ /* We can arrive here with a NULL tstate during initialization:
+ try running "python -Wi" for an example related to string
+ interning. Let's just hope that no exception occurs then... */
+ tstate = PyThreadState_GET();
+ if (tstate != NULL && tstate->curexc_type != NULL) {
+ /* preserve the existing exception */
+ PyObject *err_type, *err_value, *err_tb;
+ PyErr_Fetch(&err_type, &err_value, &err_tb);
+ ep = (mp->ma_lookup)(mp, key, hash);
+ /* ignore errors */
+ PyErr_Restore(err_type, err_value, err_tb);
+ if (ep == NULL)
+ return NULL;
+ }
+ else {
+ ep = (mp->ma_lookup)(mp, key, hash);
+ if (ep == NULL) {
+ PyErr_Clear();
+ return NULL;
+ }
+ }
+ return ep->me_value;
}
/* CAUTION: PyDict_SetItem() must guarantee that it won't resize the
@@ -568,7 +600,8 @@ PyDict_SetItem(register PyObject *op, PyObject *key, PyObject *value)
n_used = mp->ma_used;
Py_INCREF(value);
Py_INCREF(key);
- insertdict(mp, key, hash, value);
+ if (insertdict(mp, key, hash, value) != 0)
+ return -1;
/* If we added a key, we can safely resize. Otherwise just return!
* If fill >= 2/3 size, adjust size. Normally, this doubles or
* quaduples the size, but it's also possible for the dict to shrink
@@ -608,6 +641,8 @@ PyDict_DelItem(PyObject *op, PyObject *key)
}
mp = (dictobject *)op;
ep = (mp->ma_lookup)(mp, key, hash);
+ if (ep == NULL)
+ return -1;
if (ep->me_value == NULL) {
PyErr_SetObject(PyExc_KeyError, key);
return -1;
@@ -893,6 +928,7 @@ dict_subscript(dictobject *mp, register PyObject *key)
{
PyObject *v;
long hash;
+ dictentry *ep;
assert(mp->ma_table != NULL);
if (!PyString_CheckExact(key) ||
(hash = ((PyStringObject *) key)->ob_shash) == -1) {
@@ -900,7 +936,10 @@ dict_subscript(dictobject *mp, register PyObject *key)
if (hash == -1)
return NULL;
}
- v = (mp->ma_lookup)(mp, key, hash) -> me_value;
+ ep = (mp->ma_lookup)(mp, key, hash);
+ if (ep == NULL)
+ return NULL;
+ v = ep->me_value;
if (v == NULL) {
if (!PyDict_CheckExact(mp)) {
/* Look up __missing__ method if we're a subclass. */
@@ -1258,9 +1297,10 @@ PyDict_Merge(PyObject *a, PyObject *b, int override)
PyDict_GetItem(a, entry->me_key) == NULL)) {
Py_INCREF(entry->me_key);
Py_INCREF(entry->me_value);
- insertdict(mp, entry->me_key,
- (long)entry->me_hash,
- entry->me_value);
+ if (insertdict(mp, entry->me_key,
+ (long)entry->me_hash,
+ entry->me_value) != 0)
+ return -1;
}
}
}
@@ -1568,13 +1608,17 @@ dict_has_key(register dictobject *mp, PyObject *key)
{
long hash;
register long ok;
+ dictentry *ep;
if (!PyString_CheckExact(key) ||
(hash = ((PyStringObject *) key)->ob_shash) == -1) {
hash = PyObject_Hash(key);
if (hash == -1)
return NULL;
}
- ok = (mp->ma_lookup)(mp, key, hash)->me_value != NULL;
+ ep = (mp->ma_lookup)(mp, key, hash);
+ if (ep == NULL)
+ return NULL;
+ ok = ep->me_value != NULL;
return PyBool_FromLong(ok);
}
@@ -1585,6 +1629,7 @@ dict_get(register dictobject *mp, PyObject *args)
PyObject *failobj = Py_None;
PyObject *val = NULL;
long hash;
+ dictentry *ep;
if (!PyArg_UnpackTuple(args, "get", 1, 2, &key, &failobj))
return NULL;
@@ -1595,8 +1640,10 @@ dict_get(register dictobject *mp, PyObject *args)
if (hash == -1)
return NULL;
}
- val = (mp->ma_lookup)(mp, key, hash)->me_value;
-
+ ep = (mp->ma_lookup)(mp, key, hash);
+ if (ep == NULL)
+ return NULL;
+ val = ep->me_value;
if (val == NULL)
val = failobj;
Py_INCREF(val);
@@ -1611,6 +1658,7 @@ dict_setdefault(register dictobject *mp, PyObject *args)
PyObject *failobj = Py_None;
PyObject *val = NULL;
long hash;
+ dictentry *ep;
if (!PyArg_UnpackTuple(args, "setdefault", 1, 2, &key, &failobj))
return NULL;
@@ -1621,7 +1669,10 @@ dict_setdefault(register dictobject *mp, PyObject *args)
if (hash == -1)
return NULL;
}
- val = (mp->ma_lookup)(mp, key, hash)->me_value;
+ ep = (mp->ma_lookup)(mp, key, hash);
+ if (ep == NULL)
+ return NULL;
+ val = ep->me_value;
if (val == NULL) {
val = failobj;
if (PyDict_SetItem((PyObject*)mp, key, failobj))
@@ -1665,6 +1716,8 @@ dict_pop(dictobject *mp, PyObject *args)
return NULL;
}
ep = (mp->ma_lookup)(mp, key, hash);
+ if (ep == NULL)
+ return NULL;
if (ep->me_value == NULL) {
if (deflt) {
Py_INCREF(deflt);
@@ -1884,6 +1937,7 @@ PyDict_Contains(PyObject *op, PyObject *key)
{
long hash;
dictobject *mp = (dictobject *)op;
+ dictentry *ep;
if (!PyString_CheckExact(key) ||
(hash = ((PyStringObject *) key)->ob_shash) == -1) {
@@ -1891,7 +1945,10 @@ PyDict_Contains(PyObject *op, PyObject *key)
if (hash == -1)
return -1;
}
- return (mp->ma_lookup)(mp, key, hash)->me_value != NULL;
+ ep = (mp->ma_lookup)(mp, key, hash);
+ if (ep == NULL)
+ return -1;
+ return ep->me_value != NULL;
}
/* Hack to implement "key in dict" */
generated by cgit v0.12 at 2024-10-23 08:29:22 (GMT)