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setobject.c
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setobject.c
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/* set object implementation
Written and maintained by Raymond D. Hettinger <[email protected]>
Derived from Lib/sets.py and Objects/dictobject.c.
Copyright (c) 2003-2007 Python Software Foundation.
All rights reserved.
*/
#include "Python.h"
#include "structmember.h"
/* Set a key error with the specified argument, wrapping it in a
* tuple automatically so that tuple keys are not unpacked as the
* exception arguments. */
static void
set_key_error(PyObject *arg)
{
PyObject *tup;
tup = PyTuple_Pack(1, arg);
if (!tup)
return; /* caller will expect error to be set anyway */
PyErr_SetObject(PyExc_KeyError, tup);
Py_DECREF(tup);
}
/* This must be >= 1. */
#define PERTURB_SHIFT 5
/* Object used as dummy key to fill deleted entries */
static PyObject *dummy = NULL; /* Initialized by first call to make_new_set() */
#ifdef Py_REF_DEBUG
PyObject *
_PySet_Dummy(void)
{
return dummy;
}
#endif
#define INIT_NONZERO_SET_SLOTS(so) do { \
(so)->table = (so)->smalltable; \
(so)->mask = PySet_MINSIZE - 1; \
(so)->hash = -1; \
} while(0)
#define EMPTY_TO_MINSIZE(so) do { \
memset((so)->smalltable, 0, sizeof((so)->smalltable)); \
(so)->used = (so)->fill = 0; \
INIT_NONZERO_SET_SLOTS(so); \
} while(0)
/* Reuse scheme to save calls to malloc, free, and memset */
#ifndef PySet_MAXFREELIST
#define PySet_MAXFREELIST 80
#endif
static PySetObject *free_list[PySet_MAXFREELIST];
static int numfree = 0;
/*
The basic lookup function used by all operations.
This is based on Algorithm D from Knuth Vol. 3, Sec. 6.4.
Open addressing is preferred over chaining since the link overhead for
chaining would be substantial (100% with typical malloc overhead).
The initial probe index is computed as hash mod the table size. Subsequent
probe indices are computed as explained in Objects/dictobject.c.
All arithmetic on hash should ignore overflow.
Unlike the dictionary implementation, the lookkey functions can return
NULL if the rich comparison returns an error.
*/
static setentry *
set_lookkey(PySetObject *so, PyObject *key, register long hash)
{
register Py_ssize_t i;
register size_t perturb;
register setentry *freeslot;
register size_t mask = so->mask;
setentry *table = so->table;
register setentry *entry;
register int cmp;
PyObject *startkey;
i = hash & mask;
entry = &table[i];
if (entry->key == NULL || entry->key == key)
return entry;
if (entry->key == dummy)
freeslot = entry;
else {
if (entry->hash == hash) {
startkey = entry->key;
Py_INCREF(startkey);
cmp = PyObject_RichCompareBool(startkey, key, Py_EQ);
Py_DECREF(startkey);
if (cmp < 0)
return NULL;
if (table == so->table && entry->key == startkey) {
if (cmp > 0)
return entry;
}
else {
/* The compare did major nasty stuff to the
* set: start over.
*/
return set_lookkey(so, key, hash);
}
}
freeslot = NULL;
}
/* In the loop, key == dummy is by far (factor of 100s) the
least likely outcome, so test for that last. */
for (perturb = hash; ; perturb >>= PERTURB_SHIFT) {
i = (i << 2) + i + perturb + 1;
entry = &table[i & mask];
if (entry->key == NULL) {
if (freeslot != NULL)
entry = freeslot;
break;
}
if (entry->key == key)
break;
if (entry->hash == hash && entry->key != dummy) {
startkey = entry->key;
Py_INCREF(startkey);
cmp = PyObject_RichCompareBool(startkey, key, Py_EQ);
Py_DECREF(startkey);
if (cmp < 0)
return NULL;
if (table == so->table && entry->key == startkey) {
if (cmp > 0)
break;
}
else {
/* The compare did major nasty stuff to the
* set: start over.
*/
return set_lookkey(so, key, hash);
}
}
else if (entry->key == dummy && freeslot == NULL)
freeslot = entry;
}
return entry;
}
/*
* Hacked up version of set_lookkey which can assume keys are always strings;
* This means we can always use _PyString_Eq directly and not have to check to
* see if the comparison altered the table.
*/
static setentry *
set_lookkey_string(PySetObject *so, PyObject *key, register long hash)
{
register Py_ssize_t i;
register size_t perturb;
register setentry *freeslot;
register size_t mask = so->mask;
setentry *table = so->table;
register setentry *entry;
/* Make sure this function doesn't have to handle non-string keys,
including subclasses of str; e.g., one reason to subclass
strings is to override __eq__, and for speed we don't cater to
that here. */
if (!PyString_CheckExact(key)) {
so->lookup = set_lookkey;
return set_lookkey(so, key, hash);
}
i = hash & mask;
entry = &table[i];
if (entry->key == NULL || entry->key == key)
return entry;
if (entry->key == dummy)
freeslot = entry;
else {
if (entry->hash == hash && _PyString_Eq(entry->key, key))
return entry;
freeslot = NULL;
}
/* In the loop, key == dummy is by far (factor of 100s) the
least likely outcome, so test for that last. */
for (perturb = hash; ; perturb >>= PERTURB_SHIFT) {
i = (i << 2) + i + perturb + 1;
entry = &table[i & mask];
if (entry->key == NULL)
return freeslot == NULL ? entry : freeslot;
if (entry->key == key
|| (entry->hash == hash
&& entry->key != dummy
&& _PyString_Eq(entry->key, key)))
return entry;
if (entry->key == dummy && freeslot == NULL)
freeslot = entry;
}
assert(0); /* NOT REACHED */
return 0;
}
/*
Internal routine to insert a new key into the table.
Used by the public insert routine.
Eats a reference to key.
*/
static int
set_insert_key(register PySetObject *so, PyObject *key, long hash)
{
register setentry *entry;
typedef setentry *(*lookupfunc)(PySetObject *, PyObject *, long);
assert(so->lookup != NULL);
entry = so->lookup(so, key, hash);
if (entry == NULL)
return -1;
if (entry->key == NULL) {
/* UNUSED */
so->fill++;
entry->key = key;
entry->hash = hash;
so->used++;
} else if (entry->key == dummy) {
/* DUMMY */
entry->key = key;
entry->hash = hash;
so->used++;
Py_DECREF(dummy);
} else {
/* ACTIVE */
Py_DECREF(key);
}
return 0;
}
/*
Internal routine used by set_table_resize() to insert an item which is
known to be absent from the set. This routine also assumes that
the set contains no deleted entries. Besides the performance benefit,
using set_insert_clean() in set_table_resize() is dangerous (SF bug #1456209).
Note that no refcounts are changed by this routine; if needed, the caller
is responsible for incref'ing `key`.
*/
static void
set_insert_clean(register PySetObject *so, PyObject *key, long hash)
{
register size_t i;
register size_t perturb;
register size_t mask = (size_t)so->mask;
setentry *table = so->table;
register setentry *entry;
i = hash & mask;
entry = &table[i];
for (perturb = hash; entry->key != NULL; perturb >>= PERTURB_SHIFT) {
i = (i << 2) + i + perturb + 1;
entry = &table[i & mask];
}
so->fill++;
entry->key = key;
entry->hash = hash;
so->used++;
}
/*
Restructure the table by allocating a new table and reinserting all
keys again. When entries have been deleted, the new table may
actually be smaller than the old one.
*/
static int
set_table_resize(PySetObject *so, Py_ssize_t minused)
{
Py_ssize_t newsize;
setentry *oldtable, *newtable, *entry;
Py_ssize_t i;
int is_oldtable_malloced;
setentry small_copy[PySet_MINSIZE];
assert(minused >= 0);
/* Find the smallest table size > minused. */
for (newsize = PySet_MINSIZE;
newsize <= minused && newsize > 0;
newsize <<= 1)
;
if (newsize <= 0) {
PyErr_NoMemory();
return -1;
}
/* Get space for a new table. */
oldtable = so->table;
assert(oldtable != NULL);
is_oldtable_malloced = oldtable != so->smalltable;
if (newsize == PySet_MINSIZE) {
/* A large table is shrinking, or we can't get any smaller. */
newtable = so->smalltable;
if (newtable == oldtable) {
if (so->fill == so->used) {
/* No dummies, so no point doing anything. */
return 0;
}
/* We're not going to resize it, but rebuild the
table anyway to purge old dummy entries.
Subtle: This is *necessary* if fill==size,
as set_lookkey needs at least one virgin slot to
terminate failing searches. If fill < size, it's
merely desirable, as dummies slow searches. */
assert(so->fill > so->used);
memcpy(small_copy, oldtable, sizeof(small_copy));
oldtable = small_copy;
}
}
else {
newtable = PyMem_NEW(setentry, newsize);
if (newtable == NULL) {
PyErr_NoMemory();
return -1;
}
}
/* Make the set empty, using the new table. */
assert(newtable != oldtable);
so->table = newtable;
so->mask = newsize - 1;
memset(newtable, 0, sizeof(setentry) * newsize);
so->used = 0;
i = so->fill;
so->fill = 0;
/* Copy the data over; this is refcount-neutral for active entries;
dummy entries aren't copied over, of course */
for (entry = oldtable; i > 0; entry++) {
if (entry->key == NULL) {
/* UNUSED */
;
} else if (entry->key == dummy) {
/* DUMMY */
--i;
assert(entry->key == dummy);
Py_DECREF(entry->key);
} else {
/* ACTIVE */
--i;
set_insert_clean(so, entry->key, entry->hash);
}
}
if (is_oldtable_malloced)
PyMem_DEL(oldtable);
return 0;
}
/* CAUTION: set_add_key/entry() must guarantee it won't resize the table */
static int
set_add_entry(register PySetObject *so, setentry *entry)
{
register Py_ssize_t n_used;
assert(so->fill <= so->mask); /* at least one empty slot */
n_used = so->used;
Py_INCREF(entry->key);
if (set_insert_key(so, entry->key, entry->hash) == -1) {
Py_DECREF(entry->key);
return -1;
}
if (!(so->used > n_used && so->fill*3 >= (so->mask+1)*2))
return 0;
return set_table_resize(so, so->used>50000 ? so->used*2 : so->used*4);
}
static int
set_add_key(register PySetObject *so, PyObject *key)
{
register long hash;
register Py_ssize_t n_used;
if (!PyString_CheckExact(key) ||
(hash = ((PyStringObject *) key)->ob_shash) == -1) {
hash = PyObject_Hash(key);
if (hash == -1)
return -1;
}
assert(so->fill <= so->mask); /* at least one empty slot */
n_used = so->used;
Py_INCREF(key);
if (set_insert_key(so, key, hash) == -1) {
Py_DECREF(key);
return -1;
}
if (!(so->used > n_used && so->fill*3 >= (so->mask+1)*2))
return 0;
return set_table_resize(so, so->used>50000 ? so->used*2 : so->used*4);
}
#define DISCARD_NOTFOUND 0
#define DISCARD_FOUND 1
static int
set_discard_entry(PySetObject *so, setentry *oldentry)
{ register setentry *entry;
PyObject *old_key;
entry = (so->lookup)(so, oldentry->key, oldentry->hash);
if (entry == NULL)
return -1;
if (entry->key == NULL || entry->key == dummy)
return DISCARD_NOTFOUND;
old_key = entry->key;
Py_INCREF(dummy);
entry->key = dummy;
so->used--;
Py_DECREF(old_key);
return DISCARD_FOUND;
}
static int
set_discard_key(PySetObject *so, PyObject *key)
{
register long hash;
register setentry *entry;
PyObject *old_key;
assert (PyAnySet_Check(so));
if (!PyString_CheckExact(key) ||
(hash = ((PyStringObject *) key)->ob_shash) == -1) {
hash = PyObject_Hash(key);
if (hash == -1)
return -1;
}
entry = (so->lookup)(so, key, hash);
if (entry == NULL)
return -1;
if (entry->key == NULL || entry->key == dummy)
return DISCARD_NOTFOUND;
old_key = entry->key;
Py_INCREF(dummy);
entry->key = dummy;
so->used--;
Py_DECREF(old_key);
return DISCARD_FOUND;
}
static int
set_clear_internal(PySetObject *so)
{
setentry *entry, *table;
int table_is_malloced;
Py_ssize_t fill;
setentry small_copy[PySet_MINSIZE];
#ifdef Py_DEBUG
Py_ssize_t i, n;
assert (PyAnySet_Check(so));
n = so->mask + 1;
i = 0;
#endif
table = so->table;
assert(table != NULL);
table_is_malloced = table != so->smalltable;
/* This is delicate. During the process of clearing the set,
* decrefs can cause the set to mutate. To avoid fatal confusion
* (voice of experience), we have to make the set empty before
* clearing the slots, and never refer to anything via so->ref while
* clearing.
*/
fill = so->fill;
if (table_is_malloced)
EMPTY_TO_MINSIZE(so);
else if (fill > 0) {
/* It's a small table with something that needs to be cleared.
* Afraid the only safe way is to copy the set entries into
* another small table first.
*/
memcpy(small_copy, table, sizeof(small_copy));
table = small_copy;
EMPTY_TO_MINSIZE(so);
}
/* else it's a small table that's already empty */
/* Now we can finally clear things. If C had refcounts, we could
* assert that the refcount on table is 1 now, i.e. that this function
* has unique access to it, so decref side-effects can't alter it.
*/
for (entry = table; fill > 0; ++entry) {
#ifdef Py_DEBUG
assert(i < n);
++i;
#endif
if (entry->key) {
--fill;
Py_DECREF(entry->key);
}
#ifdef Py_DEBUG
else
assert(entry->key == NULL);
#endif
}
if (table_is_malloced)
PyMem_DEL(table);
return 0;
}
/*
* Iterate over a set table. Use like so:
*
* Py_ssize_t pos;
* setentry *entry;
* pos = 0; # important! pos should not otherwise be changed by you
* while (set_next(yourset, &pos, &entry)) {
* Refer to borrowed reference in entry->key.
* }
*
* CAUTION: In general, it isn't safe to use set_next in a loop that
* mutates the table.
*/
static int
set_next(PySetObject *so, Py_ssize_t *pos_ptr, setentry **entry_ptr)
{
Py_ssize_t i;
Py_ssize_t mask;
register setentry *table;
assert (PyAnySet_Check(so));
i = *pos_ptr;
assert(i >= 0);
table = so->table;
mask = so->mask;
while (i <= mask && (table[i].key == NULL || table[i].key == dummy))
i++;
*pos_ptr = i+1;
if (i > mask)
return 0;
assert(table[i].key != NULL);
*entry_ptr = &table[i];
return 1;
}
static void
set_dealloc(PySetObject *so)
{
register setentry *entry;
Py_ssize_t fill = so->fill;
PyObject_GC_UnTrack(so);
Py_TRASHCAN_SAFE_BEGIN(so)
if (so->weakreflist != NULL)
PyObject_ClearWeakRefs((PyObject *) so);
for (entry = so->table; fill > 0; entry++) {
if (entry->key) {
--fill;
Py_DECREF(entry->key);
}
}
if (so->table != so->smalltable)
PyMem_DEL(so->table);
if (numfree < PySet_MAXFREELIST && PyAnySet_CheckExact(so))
free_list[numfree++] = so;
else
Py_TYPE(so)->tp_free(so);
Py_TRASHCAN_SAFE_END(so)
}
static int
set_tp_print(PySetObject *so, FILE *fp, int flags)
{
setentry *entry;
Py_ssize_t pos=0;
char *emit = ""; /* No separator emitted on first pass */
char *separator = ", ";
int status = Py_ReprEnter((PyObject*)so);
if (status != 0) {
if (status < 0)
return status;
Py_BEGIN_ALLOW_THREADS
fprintf(fp, "%s(...)", so->ob_type->tp_name);
Py_END_ALLOW_THREADS
return 0;
}
Py_BEGIN_ALLOW_THREADS
fprintf(fp, "%s([", so->ob_type->tp_name);
Py_END_ALLOW_THREADS
while (set_next(so, &pos, &entry)) {
Py_BEGIN_ALLOW_THREADS
fputs(emit, fp);
Py_END_ALLOW_THREADS
emit = separator;
if (PyObject_Print(entry->key, fp, 0) != 0) {
Py_ReprLeave((PyObject*)so);
return -1;
}
}
Py_BEGIN_ALLOW_THREADS
fputs("])", fp);
Py_END_ALLOW_THREADS
Py_ReprLeave((PyObject*)so);
return 0;
}
static PyObject *
set_repr(PySetObject *so)
{
PyObject *keys, *result=NULL, *listrepr;
int status = Py_ReprEnter((PyObject*)so);
if (status != 0) {
if (status < 0)
return NULL;
return PyString_FromFormat("%s(...)", so->ob_type->tp_name);
}
keys = PySequence_List((PyObject *)so);
if (keys == NULL)
goto done;
listrepr = PyObject_Repr(keys);
Py_DECREF(keys);
if (listrepr == NULL)
goto done;
result = PyString_FromFormat("%s(%s)", so->ob_type->tp_name,
PyString_AS_STRING(listrepr));
Py_DECREF(listrepr);
done:
Py_ReprLeave((PyObject*)so);
return result;
}
static Py_ssize_t
set_len(PyObject *so)
{
return ((PySetObject *)so)->used;
}
static int
set_merge(PySetObject *so, PyObject *otherset)
{
PySetObject *other;
register Py_ssize_t i;
register setentry *entry;
assert (PyAnySet_Check(so));
assert (PyAnySet_Check(otherset));
other = (PySetObject*)otherset;
if (other == so || other->used == 0)
/* a.update(a) or a.update({}); nothing to do */
return 0;
/* Do one big resize at the start, rather than
* incrementally resizing as we insert new keys. Expect
* that there will be no (or few) overlapping keys.
*/
if ((so->fill + other->used)*3 >= (so->mask+1)*2) {
if (set_table_resize(so, (so->used + other->used)*2) != 0)
return -1;
}
for (i = 0; i <= other->mask; i++) {
entry = &other->table[i];
if (entry->key != NULL &&
entry->key != dummy) {
Py_INCREF(entry->key);
if (set_insert_key(so, entry->key, entry->hash) == -1) {
Py_DECREF(entry->key);
return -1;
}
}
}
return 0;
}
static int
set_contains_key(PySetObject *so, PyObject *key)
{
long hash;
setentry *entry;
if (!PyString_CheckExact(key) ||
(hash = ((PyStringObject *) key)->ob_shash) == -1) {
hash = PyObject_Hash(key);
if (hash == -1)
return -1;
}
entry = (so->lookup)(so, key, hash);
if (entry == NULL)
return -1;
key = entry->key;
return key != NULL && key != dummy;
}
static int
set_contains_entry(PySetObject *so, setentry *entry)
{
PyObject *key;
setentry *lu_entry;
lu_entry = (so->lookup)(so, entry->key, entry->hash);
if (lu_entry == NULL)
return -1;
key = lu_entry->key;
return key != NULL && key != dummy;
}
static PyObject *
set_pop(PySetObject *so)
{
register Py_ssize_t i = 0;
register setentry *entry;
PyObject *key;
assert (PyAnySet_Check(so));
if (so->used == 0) {
PyErr_SetString(PyExc_KeyError, "pop from an empty set");
return NULL;
}
/* Set entry to "the first" unused or dummy set entry. We abuse
* the hash field of slot 0 to hold a search finger:
* If slot 0 has a value, use slot 0.
* Else slot 0 is being used to hold a search finger,
* and we use its hash value as the first index to look.
*/
entry = &so->table[0];
if (entry->key == NULL || entry->key == dummy) {
i = entry->hash;
/* The hash field may be a real hash value, or it may be a
* legit search finger, or it may be a once-legit search
* finger that's out of bounds now because it wrapped around
* or the table shrunk -- simply make sure it's in bounds now.
*/
if (i > so->mask || i < 1)
i = 1; /* skip slot 0 */
while ((entry = &so->table[i])->key == NULL || entry->key==dummy) {
i++;
if (i > so->mask)
i = 1;
}
}
key = entry->key;
Py_INCREF(dummy);
entry->key = dummy;
so->used--;
so->table[0].hash = i + 1; /* next place to start */
return key;
}
PyDoc_STRVAR(pop_doc, "Remove and return an arbitrary set element.\n\
Raises KeyError if the set is empty.");
static int
set_traverse(PySetObject *so, visitproc visit, void *arg)
{
Py_ssize_t pos = 0;
setentry *entry;
while (set_next(so, &pos, &entry))
Py_VISIT(entry->key);
return 0;
}
static long
frozenset_hash(PyObject *self)
{
PySetObject *so = (PySetObject *)self;
long h, hash = 1927868237L;
setentry *entry;
Py_ssize_t pos = 0;
if (so->hash != -1)
return so->hash;
hash *= PySet_GET_SIZE(self) + 1;
while (set_next(so, &pos, &entry)) {
/* Work to increase the bit dispersion for closely spaced hash
values. The is important because some use cases have many
combinations of a small number of elements with nearby
hashes so that many distinct combinations collapse to only
a handful of distinct hash values. */
h = entry->hash;
hash ^= (h ^ (h << 16) ^ 89869747L) * 3644798167u;
}
hash = hash * 69069L + 907133923L;
if (hash == -1)
hash = 590923713L;
so->hash = hash;
return hash;
}
/***** Set iterator type ***********************************************/
typedef struct {
PyObject_HEAD
PySetObject *si_set; /* Set to NULL when iterator is exhausted */
Py_ssize_t si_used;
Py_ssize_t si_pos;
Py_ssize_t len;
} setiterobject;
static void
setiter_dealloc(setiterobject *si)
{
Py_XDECREF(si->si_set);
PyObject_GC_Del(si);
}
static int
setiter_traverse(setiterobject *si, visitproc visit, void *arg)
{
Py_VISIT(si->si_set);
return 0;
}
static PyObject *
setiter_len(setiterobject *si)
{
Py_ssize_t len = 0;
if (si->si_set != NULL && si->si_used == si->si_set->used)
len = si->len;
return PyInt_FromLong(len);
}
PyDoc_STRVAR(length_hint_doc, "Private method returning an estimate of len(list(it)).");
static PyMethodDef setiter_methods[] = {
{"__length_hint__", (PyCFunction)setiter_len, METH_NOARGS, length_hint_doc},
{NULL, NULL} /* sentinel */
};
static PyObject *setiter_iternext(setiterobject *si)
{
PyObject *key;
register Py_ssize_t i, mask;
register setentry *entry;
PySetObject *so = si->si_set;
if (so == NULL)
return NULL;
assert (PyAnySet_Check(so));
if (si->si_used != so->used) {
PyErr_SetString(PyExc_RuntimeError,
"Set changed size during iteration");
si->si_used = -1; /* Make this state sticky */
return NULL;
}
i = si->si_pos;
assert(i>=0);
entry = so->table;
mask = so->mask;
while (i <= mask && (entry[i].key == NULL || entry[i].key == dummy))
i++;
si->si_pos = i+1;
if (i > mask)
goto fail;
si->len--;
key = entry[i].key;
Py_INCREF(key);
return key;
fail:
Py_DECREF(so);
si->si_set = NULL;
return NULL;
}
static PyTypeObject PySetIter_Type = {
PyVarObject_HEAD_INIT(&PyType_Type, 0)
"setiterator", /* tp_name */
sizeof(setiterobject), /* tp_basicsize */
0, /* tp_itemsize */
/* methods */
(destructor)setiter_dealloc, /* tp_dealloc */
0, /* tp_print */
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_compare */
0, /* tp_repr */
0, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */
0, /* tp_hash */
0, /* tp_call */
0, /* tp_str */
PyObject_GenericGetAttr, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
0, /* tp_doc */
(traverseproc)setiter_traverse, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
PyObject_SelfIter, /* tp_iter */
(iternextfunc)setiter_iternext, /* tp_iternext */
setiter_methods, /* tp_methods */
0,
};
static PyObject *
set_iter(PySetObject *so)
{
setiterobject *si = PyObject_GC_New(setiterobject, &PySetIter_Type);
if (si == NULL)
return NULL;
Py_INCREF(so);
si->si_set = so;
si->si_used = so->used;
si->si_pos = 0;
si->len = so->used;
_PyObject_GC_TRACK(si);
return (PyObject *)si;
}
static int
set_update_internal(PySetObject *so, PyObject *other)
{
PyObject *key, *it;
if (PyAnySet_Check(other))
return set_merge(so, other);
if (PyDict_CheckExact(other)) {
PyObject *value;
Py_ssize_t pos = 0;
long hash;
Py_ssize_t dictsize = PyDict_Size(other);
/* Do one big resize at the start, rather than
* incrementally resizing as we insert new keys. Expect
* that there will be no (or few) overlapping keys.
*/
if (dictsize == -1)
return -1;
if ((so->fill + dictsize)*3 >= (so->mask+1)*2) {
if (set_table_resize(so, (so->used + dictsize)*2) != 0)
return -1;
}
while (_PyDict_Next(other, &pos, &key, &value, &hash)) {
setentry an_entry;
an_entry.hash = hash;
an_entry.key = key;
if (set_add_entry(so, &an_entry) == -1)
return -1;
}
return 0;
}
it = PyObject_GetIter(other);
if (it == NULL)
return -1;
while ((key = PyIter_Next(it)) != NULL) {
if (set_add_key(so, key) == -1) {
Py_DECREF(it);
Py_DECREF(key);
return -1;
}
Py_DECREF(key);
}
Py_DECREF(it);
if (PyErr_Occurred())
return -1;
return 0;
}
static PyObject *
set_update(PySetObject *so, PyObject *args)
{
Py_ssize_t i;
for (i=0 ; i<PyTuple_GET_SIZE(args) ; i++) {
PyObject *other = PyTuple_GET_ITEM(args, i);
if (set_update_internal(so, other) == -1)
return NULL;
}
Py_RETURN_NONE;
}
PyDoc_STRVAR(update_doc,
"Update a set with the union of itself and others.");
static PyObject *
make_new_set(PyTypeObject *type, PyObject *iterable)
{
register PySetObject *so = NULL;
if (dummy == NULL) { /* Auto-initialize dummy */
dummy = PyString_FromString("<dummy key>");