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3053 lines (2630 loc) · 82.8 KB
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/*
This file is the C part of the bitarray package. Almost all
functionality is implemented here.
Author: Ilan Schnell
*/
#define PY_SSIZE_T_CLEAN
#include "Python.h"
#if PY_MAJOR_VERSION >= 3
#define IS_PY3K
#endif
#ifdef IS_PY3K
#include "bytesobject.h"
#define PyString_FromStringAndSize PyBytes_FromStringAndSize
#define PyString_FromString PyBytes_FromString
#define PyString_Check PyBytes_Check
#define PyString_Size PyBytes_Size
#define PyString_AsString PyBytes_AsString
#define PyString_ConcatAndDel PyBytes_ConcatAndDel
#define Py_TPFLAGS_HAVE_WEAKREFS 0
#endif
#if PY_MAJOR_VERSION == 2 && PY_MINOR_VERSION < 5
/* Py_ssize_t was introduced in Python 2.5, substitute long for it */
typedef long Py_ssize_t;
#define PY_SSIZE_T_MAX LONG_MAX
#define PY_SSIZE_T_MIN LONG_MIN
Py_ssize_t PyNumber_AsSsize_t(PyObject *o, PyObject *exc)
{
return PyLong_AsLong(o);
}
int PyIndex_Check(PyObject *o)
{
return 0;
}
#define PY_SSIZE_T_FMT "l"
#else
/* Python 2.5 and up uses 'n' as the format char for Py_ssize_t */
#define PY_SSIZE_T_FMT "n"
#endif
#if PY_MAJOR_VERSION == 2 && PY_MINOR_VERSION < 6
/* backward compatibility with Python 2.5 */
#define Py_TYPE(ob) (((PyObject *) (ob))->ob_type)
#define Py_SIZE(ob) (((PyVarObject *) (ob))->ob_size)
#endif
#if PY_MAJOR_VERSION == 2 && PY_MINOR_VERSION == 7
/* (new) buffer protocol */
#define WITH_BUFFER
#endif
#ifdef STDC_HEADERS
#include <stddef.h>
#else /* !STDC_HEADERS */
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h> /* For size_t */
#endif /* HAVE_SYS_TYPES_H */
#endif /* !STDC_HEADERS */
typedef long long int idx_t;
/* throughout: 0 = little endian 1 = big endian */
#define DEFAULT_ENDIAN 1
typedef struct {
PyObject_VAR_HEAD
#ifdef WITH_BUFFER
int ob_exports; /* how many buffer exports */
#endif
char *ob_item;
Py_ssize_t allocated; /* how many bytes allocated */
idx_t nbits; /* length og bitarray */
int endian; /* bit endianness of bitarray */
PyObject *weakreflist; /* list of weak references */
} bitarrayobject;
static PyTypeObject Bitarraytype;
#define bitarray_Check(obj) PyObject_TypeCheck(obj, &Bitarraytype)
#define BITS(bytes) (((idx_t) 8) * ((idx_t) (bytes)))
#define BYTES(bits) (((bits) == 0) ? 0 : (((bits) - 1) / 8 + 1))
#define BITMASK(endian, i) (((char) 1) << ((endian) ? (7 - (i)%8) : (i)%8))
/* ------------ low level access to bits in bitarrayobject ------------- */
#define GETBIT(self, i) \
((self)->ob_item[(i) / 8] & BITMASK((self)->endian, i) ? 1 : 0)
static void
setbit(bitarrayobject *self, idx_t i, int bit)
{
char *cp, mask;
mask = BITMASK(self->endian, i);
cp = self->ob_item + i / 8;
if (bit)
*cp |= mask;
else
*cp &= ~mask;
}
static int
check_overflow(idx_t nbits)
{
idx_t max_bits;
assert(nbits >= 0);
if (sizeof(void *) == 4) { /* 32bit machine */
max_bits = ((idx_t) 1) << 34; /* 2^34 = 16 Gbits*/
if (nbits > max_bits) {
char buff[256];
sprintf(buff, "cannot create bitarray of size %lld, "
"max size is %lld", nbits, max_bits);
PyErr_SetString(PyExc_OverflowError, buff);
return -1;
}
}
return 0;
}
static int
resize(bitarrayobject *self, idx_t nbits)
{
Py_ssize_t newsize;
size_t _new_size; /* for allocation */
if (check_overflow(nbits) < 0)
return -1;
newsize = (Py_ssize_t) BYTES(nbits);
/* Bypass realloc() when a previous overallocation is large enough
to accommodate the newsize. If the newsize is 16 smaller than the
current size, then proceed with the realloc() to shrink the list.
*/
if (self->allocated >= newsize &&
Py_SIZE(self) < newsize + 16 &&
self->ob_item != NULL)
{
Py_SIZE(self) = newsize;
self->nbits = nbits;
return 0;
}
if (newsize >= Py_SIZE(self) + 65536)
/* Don't overallocate when the size increase is very large. */
_new_size = newsize;
else
/* This over-allocates proportional to the bitarray size, making
room for additional growth. The over-allocation is mild, but is
enough to give linear-time amortized behavior over a long
sequence of appends() in the presence of a poorly-performing
system realloc().
The growth pattern is: 0, 4, 8, 16, 25, 34, 44, 54, 65, 77, ...
Note, the pattern starts out the same as for lists but then
grows at a smaller rate so that larger bitarrays only overallocate
by about 1/16th -- this is done because bitarrays are assumed
to be memory critical.
*/
_new_size = (newsize >> 4) + (Py_SIZE(self) < 8 ? 3 : 7) + newsize;
self->ob_item = PyMem_Realloc(self->ob_item, _new_size);
if (self->ob_item == NULL) {
PyErr_NoMemory();
return -1;
}
Py_SIZE(self) = newsize;
self->allocated = _new_size;
self->nbits = nbits;
return 0;
}
/* create new bitarray object without initialization of buffer */
static PyObject *
newbitarrayobject(PyTypeObject *type, idx_t nbits, int endian)
{
bitarrayobject *obj;
Py_ssize_t nbytes;
if (check_overflow(nbits) < 0)
return NULL;
obj = (bitarrayobject *) type->tp_alloc(type, 0);
if (obj == NULL)
return NULL;
nbytes = (Py_ssize_t) BYTES(nbits);
Py_SIZE(obj) = nbytes;
obj->nbits = nbits;
obj->endian = endian;
if (nbytes == 0) {
obj->ob_item = NULL;
}
else {
obj->ob_item = PyMem_Malloc((size_t) nbytes);
if (obj->ob_item == NULL) {
PyObject_Del(obj);
PyErr_NoMemory();
return NULL;
}
}
obj->allocated = nbytes;
obj->weakreflist = NULL;
return (PyObject *) obj;
}
static void
bitarray_dealloc(bitarrayobject *self)
{
if (self->weakreflist != NULL)
PyObject_ClearWeakRefs((PyObject *) self);
if (self->ob_item != NULL)
PyMem_Free((void *) self->ob_item);
Py_TYPE(self)->tp_free((PyObject *) self);
}
/* copy n bits from other (starting at b) onto self (starting at a) */
static void
copy_n(bitarrayobject *self, idx_t a,
bitarrayobject *other, idx_t b, idx_t n)
{
idx_t i;
assert(0 <= n && n <= self->nbits && n <= other->nbits);
assert(0 <= a && a <= self->nbits - n);
assert(0 <= b && b <= other->nbits - n);
/* XXX
if (self->endian == other->endian && a % 8 == 0 && b % 8 == 0 && n >= 8)
{
Py_ssize_t bytes;
idx_t bits;
bytes = n / 8;
bits = 8 * bytes;
copy_n(self, bits + a, other, bits + b, n - bits);
memmove(self->ob_item + a / 8, other->ob_item + b / 8, bytes);
return;
}
*/
/* the different type of looping is only relevant when other and self
are the same object, i.e. when copying a piece of an bitarrayobject
onto itself */
if (a < b) {
for (i = 0; i < n; i++) /* loop forward (delete) */
setbit(self, i + a, GETBIT(other, i + b));
}
else {
for (i = n - 1; i >= 0; i--) /* loop backwards (insert) */
setbit(self, i + a, GETBIT(other, i + b));
}
}
/* starting at start, delete n bits from self */
static int
delete_n(bitarrayobject *self, idx_t start, idx_t n)
{
assert(0 <= start && start <= self->nbits);
assert(0 <= n && n <= self->nbits - start);
if (n == 0)
return 0;
copy_n(self, start, self, start + n, self->nbits - start - n);
return resize(self, self->nbits - n);
}
/* starting at start, insert n (uninitialized) bits into self */
static int
insert_n(bitarrayobject *self, idx_t start, idx_t n)
{
assert(0 <= start && start <= self->nbits);
assert(n >= 0);
if (n == 0)
return 0;
if (resize(self, self->nbits + n) < 0)
return -1;
copy_n(self, start + n, self, start, self->nbits - start - n);
return 0;
}
/* sets ususet bits to 0, i.e. the ones in the last byte (if any),
and return the number of bits set -- self->nbits is unchanged */
static int
setunused(bitarrayobject *self)
{
idx_t i, n;
int res = 0;
n = BITS(Py_SIZE(self));
for (i = self->nbits; i < n; i++) {
setbit(self, i, 0);
res++;
}
assert(res < 8);
return res;
}
/* repeat self n times */
static int
repeat(bitarrayobject *self, idx_t n)
{
idx_t nbits, i;
if (n <= 0) {
if (resize(self, 0) < 0)
return -1;
}
if (n > 1) {
nbits = self->nbits;
if (resize(self, nbits * n) < 0)
return -1;
for (i = 1; i < n; i++)
copy_n(self, i * nbits, self, 0, nbits);
}
return 0;
}
enum op_type {
OP_and,
OP_or,
OP_xor,
};
/* perform bitwise operation */
static int
bitwise(bitarrayobject *self, PyObject *arg, enum op_type oper)
{
bitarrayobject *other;
Py_ssize_t i;
if (!bitarray_Check(arg)) {
PyErr_SetString(PyExc_TypeError,
"bitarray object expected for bitwise operation");
return -1;
}
other = (bitarrayobject *) arg;
if (self->nbits != other->nbits) {
PyErr_SetString(PyExc_ValueError,
"bitarrays of equal length expected for bitwise operation");
return -1;
}
setunused(self);
setunused(other);
switch (oper) {
case OP_and:
for (i = 0; i < Py_SIZE(self); i++)
self->ob_item[i] &= other->ob_item[i];
break;
case OP_or:
for (i = 0; i < Py_SIZE(self); i++)
self->ob_item[i] |= other->ob_item[i];
break;
case OP_xor:
for (i = 0; i < Py_SIZE(self); i++)
self->ob_item[i] ^= other->ob_item[i];
break;
}
return 0;
}
/* set the bits from start to stop (excluding) in self to val */
static void
setrange(bitarrayobject *self, idx_t start, idx_t stop, int val)
{
idx_t i;
assert(0 <= start && start <= self->nbits);
assert(0 <= stop && stop <= self->nbits);
for (i = start; i < stop; i++)
setbit(self, i, val);
}
static void
invert(bitarrayobject *self)
{
Py_ssize_t i;
for (i = 0; i < Py_SIZE(self); i++)
self->ob_item[i] = ~self->ob_item[i];
}
/* reverse the order of bits in each byte of the buffer */
static void
bytereverse(bitarrayobject *self)
{
static char trans[256];
static int setup = 0;
Py_ssize_t i;
unsigned char c;
if (!setup) {
/* setup translation table, which maps each byte to it's reversed:
trans = {0, 128, 64, 192, 32, 160, ..., 255} */
int j, k;
for (k = 0; k < 256; k++) {
trans[k] = 0x00;
for (j = 0; j < 8; j++)
if (1 << (7 - j) & k)
trans[k] |= 1 << j;
}
setup = 1;
}
setunused(self);
for (i = 0; i < Py_SIZE(self); i++) {
c = self->ob_item[i];
self->ob_item[i] = trans[c];
}
}
static int bitcount_lookup[256] = {
0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8,
};
/* returns number of 1 bits */
static idx_t
count(bitarrayobject *self)
{
Py_ssize_t i;
idx_t res = 0;
unsigned char c;
setunused(self);
for (i = 0; i < Py_SIZE(self); i++) {
c = self->ob_item[i];
res += bitcount_lookup[c];
}
return res;
}
/* return index of first occurrence of vi, -1 when x is not in found. */
static idx_t
findfirst(bitarrayobject *self, int vi, idx_t start, idx_t stop)
{
Py_ssize_t j;
idx_t i;
char c;
if (Py_SIZE(self) == 0)
return -1;
if (start < 0 || start > self->nbits)
start = 0;
if (stop < 0 || stop > self->nbits)
stop = self->nbits;
if (start >= stop)
return -1;
if (stop > start + 8) {
/* seraching for 1 means: break when byte is not 0x00
searching for 0 means: break when byte is not 0xff */
c = vi ? 0x00 : 0xff;
/* skip ahead by checking whole bytes */
for (j = (Py_ssize_t) (start / 8); j < BYTES(stop); j++)
if (c ^ self->ob_item[j])
break;
if (j == Py_SIZE(self))
j--;
assert(0 <= j && j < Py_SIZE(self));
if (start < BITS(j))
start = BITS(j);
}
/* fine grained search */
for (i = start; i < stop; i++)
if (GETBIT(self, i) == vi)
return i;
return -1;
}
/* search for the first occurrence bitarray xa (in self), starting at p,
and return its position (-1 when not found)
*/
static idx_t
search(bitarrayobject *self, bitarrayobject *xa, idx_t p)
{
idx_t i;
assert(p >= 0);
while (p < self->nbits - xa->nbits + 1) {
for (i = 0; i < xa->nbits; i++)
if (GETBIT(self, p + i) != GETBIT(xa, i))
goto next;
return p;
next:
p++;
}
return -1;
}
static int
set_item(bitarrayobject *self, idx_t i, PyObject *v)
{
long vi;
assert(0 <= i && i < self->nbits);
vi = PyObject_IsTrue(v);
if (vi < 0)
return -1;
setbit(self, i, vi);
return 0;
}
static int
append_item(bitarrayobject *self, PyObject *item)
{
if (resize(self, self->nbits + 1) < 0)
return -1;
return set_item(self, self->nbits - 1, item);
}
static PyObject *
unpack(bitarrayobject *self, char zero, char one)
{
PyObject *res;
Py_ssize_t i;
char *str;
if (self->nbits > PY_SSIZE_T_MAX) {
PyErr_SetString(PyExc_OverflowError, "bitarray too large to unpack");
return NULL;
}
str = PyMem_Malloc((size_t) self->nbits);
if (str == NULL) {
PyErr_NoMemory();
return NULL;
}
for (i = 0; i < self->nbits; i++) {
*(str + i) = GETBIT(self, i) ? one : zero;
}
res = PyString_FromStringAndSize(str, (Py_ssize_t) self->nbits);
PyMem_Free((void *) str);
return res;
}
static int
extend_bitarray(bitarrayobject *self, bitarrayobject *other)
{
idx_t n_sum;
if (other->nbits == 0)
return 0;
n_sum = self->nbits + other->nbits;
if (resize(self, n_sum) < 0)
return -1;
copy_n(self, n_sum - other->nbits, other, 0, other->nbits);
return 0;
}
static int
extend_iter(bitarrayobject *self, PyObject *iter)
{
PyObject *item;
assert(PyIter_Check(iter));
while ((item = PyIter_Next(iter)) != NULL) {
if (append_item(self, item) < 0) {
Py_DECREF(item);
return -1;
}
Py_DECREF(item);
}
if (PyErr_Occurred())
return -1;
return 0;
}
static int
extend_list(bitarrayobject *self, PyObject *list)
{
PyObject *item;
Py_ssize_t n, i;
assert(PyList_Check(list));
n = PyList_Size(list);
if (n == 0)
return 0;
if (resize(self, self->nbits + n) < 0)
return -1;
for (i = 0; i < n; i++) {
item = PyList_GetItem(list, i);
if (item == NULL)
return -1;
if (set_item(self, self->nbits - n + i, item) < 0)
return -1;
}
return 0;
}
static int
extend_tuple(bitarrayobject *self, PyObject *tuple)
{
PyObject *item;
Py_ssize_t n, i;
assert(PyTuple_Check(tuple));
n = PyTuple_Size(tuple);
if (n == 0)
return 0;
if (resize(self, self->nbits + n) < 0)
return -1;
for (i = 0; i < n; i++) {
item = PyTuple_GetItem(tuple, i);
if (item == NULL)
return -1;
if (set_item(self, self->nbits - n + i, item) < 0)
return -1;
}
return 0;
}
/* extend_string(): extend the bitarray from a string, where each whole
characters is converted to a single bit
*/
enum conv_tp {
STR_01, /* '0' -> 0 '1' -> 1 no other characters allowed */
STR_RAW, /* 0x00 -> 0 other -> 1 */
};
static int
extend_string(bitarrayobject *self, PyObject *string, enum conv_tp conv)
{
Py_ssize_t strlen, i;
char c, *str;
int vi = 0;
assert(PyString_Check(string));
strlen = PyString_Size(string);
if (strlen == 0)
return 0;
if (resize(self, self->nbits + strlen) < 0)
return -1;
str = PyString_AsString(string);
for (i = 0; i < strlen; i++) {
c = *(str + i);
/* depending on conv, map c to bit */
switch (conv) {
case STR_01:
switch (c) {
case '0': vi = 0; break;
case '1': vi = 1; break;
default:
PyErr_Format(PyExc_ValueError,
"character must be '0' or '1', found '%c'", c);
return -1;
}
break;
case STR_RAW:
vi = c ? 1 : 0;
break;
}
setbit(self, self->nbits - strlen + i, vi);
}
return 0;
}
static int
extend_rawstring(bitarrayobject *self, PyObject *string)
{
Py_ssize_t strlen;
char *str;
assert(PyString_Check(string) && self->nbits % 8 == 0);
strlen = PyString_Size(string);
if (strlen == 0)
return 0;
if (resize(self, self->nbits + BITS(strlen)) < 0)
return -1;
str = PyString_AsString(string);
memcpy(self->ob_item + (Py_SIZE(self) - strlen), str, strlen);
return 0;
}
static int
extend_dispatch(bitarrayobject *self, PyObject *obj)
{
PyObject *iter;
int ret;
/* dispatch on type */
if (bitarray_Check(obj)) /* bitarray */
return extend_bitarray(self, (bitarrayobject *) obj);
if (PyList_Check(obj)) /* list */
return extend_list(self, obj);
if (PyTuple_Check(obj)) /* tuple */
return extend_tuple(self, obj);
if (PyString_Check(obj)) /* str01 */
return extend_string(self, obj, STR_01);
#ifdef IS_PY3K
if (PyUnicode_Check(obj)) { /* str01 */
PyObject *string;
string = PyUnicode_AsEncodedString(obj, NULL, NULL);
ret = extend_string(self, string, STR_01);
Py_DECREF(string);
return ret;
}
#endif
if (PyIter_Check(obj)) /* iter */
return extend_iter(self, obj);
/* finally, try to get the iterator of the object */
iter = PyObject_GetIter(obj);
if (iter == NULL) {
PyErr_SetString(PyExc_TypeError, "could not extend bitarray");
return -1;
}
ret = extend_iter(self, iter);
Py_DECREF(iter);
return ret;
}
/* --------- helper functions NOT involving bitarrayobjects ------------ */
#define ENDIAN_STR(ba) (((ba)->endian) ? "big" : "little")
#ifdef IS_PY3K
#define IS_INDEX(x) (PyLong_Check(x) || PyIndex_Check(x))
#define IS_INT_OR_BOOL(x) (PyBool_Check(x) || PyLong_Check(x))
#else
#define IS_INDEX(x) (PyInt_Check(x) || PyLong_Check(x) || PyIndex_Check(x))
#define IS_INT_OR_BOOL(x) (PyBool_Check(x) || PyInt_Check(x) || \
PyLong_Check(x))
#endif
/* given an PyLong (which must be 0 or 1), or a PyBool, return 0 or 1,
or -1 on error */
static int
IntBool_AsInt(PyObject *v)
{
long x;
if (PyBool_Check(v))
return PyObject_IsTrue(v);
#ifndef IS_PY3K
if (PyInt_Check(v)) {
x = PyInt_AsLong(v);
}
else
#endif
if (PyLong_Check(v)) {
x = PyLong_AsLong(v);
}
else {
PyErr_SetString(PyExc_TypeError, "integer or bool expected");
return -1;
}
if (x < 0 || x > 1) {
PyErr_SetString(PyExc_ValueError,
"integer value between 0 and 1 expected");
return -1;
}
return (int) x;
}
/* Extract a slice index from a PyInt or PyLong or an object with the
nb_index slot defined, and store in *i.
However, this function returns -1 on error and 0 on success.
This is almost _PyEval_SliceIndex() with Py_ssize_t replaced by idx_t
*/
static int
getIndex(PyObject *v, idx_t *i)
{
idx_t x;
#ifndef IS_PY3K
if (PyInt_Check(v)) {
x = PyInt_AS_LONG(v);
}
else
#endif
if (PyLong_Check(v)) {
x = PyLong_AsLongLong(v);
}
else if (PyIndex_Check(v)) {
x = PyNumber_AsSsize_t(v, NULL);
if (x == -1 && PyErr_Occurred())
return -1;
}
else {
PyErr_SetString(PyExc_TypeError, "slice indices must be integers or "
"None or have an __index__ method");
return -1;
}
*i = x;
return 0;
}
/* this is PySlice_GetIndicesEx() with Py_ssize_t replaced by idx_t */
static int
slice_GetIndicesEx(PySliceObject *r, idx_t length,
idx_t *start, idx_t *stop, idx_t *step, idx_t *slicelength)
{
idx_t defstart, defstop;
if (r->step == Py_None) {
*step = 1;
}
else {
if (getIndex(r->step, step) < 0)
return -1;
if (*step == 0) {
PyErr_SetString(PyExc_ValueError, "slice step cannot be zero");
return -1;
}
}
defstart = *step < 0 ? length - 1 : 0;
defstop = *step < 0 ? -1 : length;
if (r->start == Py_None) {
*start = defstart;
}
else {
if (getIndex(r->start, start) < 0)
return -1;
if (*start < 0) *start += length;
if (*start < 0) *start = (*step < 0) ? -1 : 0;
if (*start >= length) *start = (*step < 0) ? length - 1 : length;
}
if (r->stop == Py_None) {
*stop = defstop;
}
else {
if (getIndex(r->stop, stop) < 0)
return -1;
if (*stop < 0) *stop += length;
if (*stop < 0) *stop = -1;
if (*stop > length) *stop = length;
}
if ((*step < 0 && *stop >= *start) || (*step > 0 && *start >= *stop)) {
*slicelength = 0;
}
else if (*step < 0) {
*slicelength = (*stop - *start + 1) / (*step) + 1;
}
else {
*slicelength = (*stop - *start - 1) / (*step) + 1;
}
return 0;
}
/**************************************************************************
Implementation of API methods
**************************************************************************/
static PyObject *
bitarray_length(bitarrayobject *self)
{
return PyLong_FromLongLong(self->nbits);
}
PyDoc_STRVAR(length_doc,
"length() -> int\n\
\n\
Return the length, i.e. number of bits stored in the bitarray.\n\
This method is preferred over __len__ (used when typing ``len(a)``),\n\
since __len__ will fail for a bitarray object with 2^31 or more elements\n\
on a 32bit machine, whereas this method will return the correct value,\n\
on 32bit and 64bit machines.");
PyDoc_STRVAR(len_doc,
"__len__() -> int\n\
\n\
Return the length, i.e. number of bits stored in the bitarray.\n\
This method will fail for a bitarray object with 2^31 or more elements\n\
on a 32bit machine. Use bitarray.length() instead.");
static PyObject *
bitarray_copy(bitarrayobject *self)
{
PyObject *res;
res = newbitarrayobject(Py_TYPE(self), self->nbits, self->endian);
if (res == NULL)
return NULL;
memcpy(((bitarrayobject *) res)->ob_item, self->ob_item, Py_SIZE(self));
return res;
}
PyDoc_STRVAR(copy_doc,
"copy() -> bitarray\n\
\n\
Return a copy of the bitarray.");
static PyObject *
bitarray_count(bitarrayobject *self, PyObject *args)
{
idx_t n1;
long x = 1;
if (!PyArg_ParseTuple(args, "|i:count", &x))
return NULL;
n1 = count(self);
return PyLong_FromLongLong(x ? n1 : (self->nbits - n1));
}
PyDoc_STRVAR(count_doc,
"count([value]) -> int\n\
\n\
Return number of occurrences of value (defaults to True) in the bitarray.");
static PyObject *
bitarray_index(bitarrayobject *self, PyObject *args)
{
PyObject *x;
idx_t i, start = 0, stop = -1;
long vi;
if (!PyArg_ParseTuple(args, "O|LL:index", &x, &start, &stop))
return NULL;
vi = PyObject_IsTrue(x);
if (vi < 0)
return NULL;
i = findfirst(self, vi, start, stop);
if (i < 0) {
PyErr_SetString(PyExc_ValueError, "index(x): x not in bitarray");
return NULL;
}
return PyLong_FromLongLong(i);
}
PyDoc_STRVAR(index_doc,
"index(value, [start, [stop]]) -> int\n\
\n\
Return index of the first occurrence of bool(value) in the bitarray.\n\
Raises ValueError if the value is not present.");
static PyObject *
bitarray_extend(bitarrayobject *self, PyObject *obj)
{
if (extend_dispatch(self, obj) < 0)
return NULL;
Py_RETURN_NONE;
}
PyDoc_STRVAR(extend_doc,
"extend(object)\n\
You can’t perform that action at this time.