ref: 2c9e3861a54e22498fb2e3226defe4393b20b202
dir: /sys/src/cmd/python/Objects/structseq.c/
/* Implementation helper: a struct that looks like a tuple. See timemodule
and posixmodule for example uses. */
#include "Python.h"
#include "structmember.h"
#include "structseq.h"
static char visible_length_key[] = "n_sequence_fields";
static char real_length_key[] = "n_fields";
static char unnamed_fields_key[] = "n_unnamed_fields";
/* Fields with this name have only a field index, not a field name.
They are only allowed for indices < n_visible_fields. */
char *PyStructSequence_UnnamedField = "unnamed field";
#define VISIBLE_SIZE(op) ((op)->ob_size)
#define VISIBLE_SIZE_TP(tp) PyInt_AsLong( \
PyDict_GetItemString((tp)->tp_dict, visible_length_key))
#define REAL_SIZE_TP(tp) PyInt_AsLong( \
PyDict_GetItemString((tp)->tp_dict, real_length_key))
#define REAL_SIZE(op) REAL_SIZE_TP((op)->ob_type)
#define UNNAMED_FIELDS_TP(tp) PyInt_AsLong( \
PyDict_GetItemString((tp)->tp_dict, unnamed_fields_key))
#define UNNAMED_FIELDS(op) UNNAMED_FIELDS_TP((op)->ob_type)
PyObject *
PyStructSequence_New(PyTypeObject *type)
{
PyStructSequence *obj;
obj = PyObject_New(PyStructSequence, type);
obj->ob_size = VISIBLE_SIZE_TP(type);
return (PyObject*) obj;
}
static void
structseq_dealloc(PyStructSequence *obj)
{
Py_ssize_t i, size;
size = REAL_SIZE(obj);
for (i = 0; i < size; ++i) {
Py_XDECREF(obj->ob_item[i]);
}
PyObject_Del(obj);
}
static Py_ssize_t
structseq_length(PyStructSequence *obj)
{
return VISIBLE_SIZE(obj);
}
static PyObject*
structseq_item(PyStructSequence *obj, Py_ssize_t i)
{
if (i < 0 || i >= VISIBLE_SIZE(obj)) {
PyErr_SetString(PyExc_IndexError, "tuple index out of range");
return NULL;
}
Py_INCREF(obj->ob_item[i]);
return obj->ob_item[i];
}
static PyObject*
structseq_slice(PyStructSequence *obj, Py_ssize_t low, Py_ssize_t high)
{
PyTupleObject *np;
Py_ssize_t i;
if (low < 0)
low = 0;
if (high > VISIBLE_SIZE(obj))
high = VISIBLE_SIZE(obj);
if (high < low)
high = low;
np = (PyTupleObject *)PyTuple_New(high-low);
if (np == NULL)
return NULL;
for(i = low; i < high; ++i) {
PyObject *v = obj->ob_item[i];
Py_INCREF(v);
PyTuple_SET_ITEM(np, i-low, v);
}
return (PyObject *) np;
}
static PyObject *
structseq_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
PyObject *arg = NULL;
PyObject *dict = NULL;
PyObject *ob;
PyStructSequence *res = NULL;
Py_ssize_t len, min_len, max_len, i, n_unnamed_fields;
static char *kwlist[] = {"sequence", "dict", 0};
if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|O:structseq",
kwlist, &arg, &dict))
return NULL;
arg = PySequence_Fast(arg, "constructor requires a sequence");
if (!arg) {
return NULL;
}
if (dict && !PyDict_Check(dict)) {
PyErr_Format(PyExc_TypeError,
"%.500s() takes a dict as second arg, if any",
type->tp_name);
Py_DECREF(arg);
return NULL;
}
len = PySequence_Fast_GET_SIZE(arg);
min_len = VISIBLE_SIZE_TP(type);
max_len = REAL_SIZE_TP(type);
n_unnamed_fields = UNNAMED_FIELDS_TP(type);
if (min_len != max_len) {
if (len < min_len) {
PyErr_Format(PyExc_TypeError,
"%.500s() takes an at least %zd-sequence (%zd-sequence given)",
type->tp_name, min_len, len);
Py_DECREF(arg);
return NULL;
}
if (len > max_len) {
PyErr_Format(PyExc_TypeError,
"%.500s() takes an at most %zd-sequence (%zd-sequence given)",
type->tp_name, max_len, len);
Py_DECREF(arg);
return NULL;
}
}
else {
if (len != min_len) {
PyErr_Format(PyExc_TypeError,
"%.500s() takes a %zd-sequence (%zd-sequence given)",
type->tp_name, min_len, len);
Py_DECREF(arg);
return NULL;
}
}
res = (PyStructSequence*) PyStructSequence_New(type);
if (res == NULL) {
return NULL;
}
for (i = 0; i < len; ++i) {
PyObject *v = PySequence_Fast_GET_ITEM(arg, i);
Py_INCREF(v);
res->ob_item[i] = v;
}
for (; i < max_len; ++i) {
if (dict && (ob = PyDict_GetItemString(
dict, type->tp_members[i-n_unnamed_fields].name))) {
}
else {
ob = Py_None;
}
Py_INCREF(ob);
res->ob_item[i] = ob;
}
Py_DECREF(arg);
return (PyObject*) res;
}
static PyObject *
make_tuple(PyStructSequence *obj)
{
return structseq_slice(obj, 0, VISIBLE_SIZE(obj));
}
static PyObject *
structseq_repr(PyStructSequence *obj)
{
PyObject *tup, *str;
tup = make_tuple(obj);
str = PyObject_Repr(tup);
Py_DECREF(tup);
return str;
}
static PyObject *
structseq_concat(PyStructSequence *obj, PyObject *b)
{
PyObject *tup, *result;
tup = make_tuple(obj);
result = PySequence_Concat(tup, b);
Py_DECREF(tup);
return result;
}
static PyObject *
structseq_repeat(PyStructSequence *obj, Py_ssize_t n)
{
PyObject *tup, *result;
tup = make_tuple(obj);
result = PySequence_Repeat(tup, n);
Py_DECREF(tup);
return result;
}
static int
structseq_contains(PyStructSequence *obj, PyObject *o)
{
PyObject *tup;
int result;
tup = make_tuple(obj);
if (!tup)
return -1;
result = PySequence_Contains(tup, o);
Py_DECREF(tup);
return result;
}
static long
structseq_hash(PyObject *obj)
{
PyObject *tup;
long result;
tup = make_tuple((PyStructSequence*) obj);
if (!tup)
return -1;
result = PyObject_Hash(tup);
Py_DECREF(tup);
return result;
}
static PyObject *
structseq_richcompare(PyObject *obj, PyObject *o2, int op)
{
PyObject *tup, *result;
tup = make_tuple((PyStructSequence*) obj);
result = PyObject_RichCompare(tup, o2, op);
Py_DECREF(tup);
return result;
}
static PyObject *
structseq_reduce(PyStructSequence* self)
{
PyObject* tup;
PyObject* dict;
PyObject* result;
Py_ssize_t n_fields, n_visible_fields, n_unnamed_fields;
int i;
n_fields = REAL_SIZE(self);
n_visible_fields = VISIBLE_SIZE(self);
n_unnamed_fields = UNNAMED_FIELDS(self);
tup = PyTuple_New(n_visible_fields);
if (!tup) {
return NULL;
}
dict = PyDict_New();
if (!dict) {
Py_DECREF(tup);
return NULL;
}
for (i = 0; i < n_visible_fields; i++) {
Py_INCREF(self->ob_item[i]);
PyTuple_SET_ITEM(tup, i, self->ob_item[i]);
}
for (; i < n_fields; i++) {
char *n = self->ob_type->tp_members[i-n_unnamed_fields].name;
PyDict_SetItemString(dict, n,
self->ob_item[i]);
}
result = Py_BuildValue("(O(OO))", self->ob_type, tup, dict);
Py_DECREF(tup);
Py_DECREF(dict);
return result;
}
static PySequenceMethods structseq_as_sequence = {
(lenfunc)structseq_length,
(binaryfunc)structseq_concat, /* sq_concat */
(ssizeargfunc)structseq_repeat, /* sq_repeat */
(ssizeargfunc)structseq_item, /* sq_item */
(ssizessizeargfunc)structseq_slice, /* sq_slice */
0, /* sq_ass_item */
0, /* sq_ass_slice */
(objobjproc)structseq_contains, /* sq_contains */
};
static PyMethodDef structseq_methods[] = {
{"__reduce__", (PyCFunction)structseq_reduce,
METH_NOARGS, NULL},
{NULL, NULL}
};
static PyTypeObject _struct_sequence_template = {
PyObject_HEAD_INIT(&PyType_Type)
0, /* ob_size */
NULL, /* tp_name */
0, /* tp_basicsize */
0, /* tp_itemsize */
(destructor)structseq_dealloc, /* tp_dealloc */
0, /* tp_print */
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_compare */
(reprfunc)structseq_repr, /* tp_repr */
0, /* tp_as_number */
&structseq_as_sequence, /* tp_as_sequence */
0, /* tp_as_mapping */
structseq_hash, /* tp_hash */
0, /* tp_call */
0, /* tp_str */
0, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT, /* tp_flags */
NULL, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
structseq_richcompare, /* tp_richcompare */
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
structseq_methods, /* tp_methods */
NULL, /* tp_members */
0, /* tp_getset */
0, /* tp_base */
0, /* tp_dict */
0, /* tp_descr_get */
0, /* tp_descr_set */
0, /* tp_dictoffset */
0, /* tp_init */
0, /* tp_alloc */
structseq_new, /* tp_new */
};
void
PyStructSequence_InitType(PyTypeObject *type, PyStructSequence_Desc *desc)
{
PyObject *dict;
PyMemberDef* members;
int n_members, n_unnamed_members, i, k;
#ifdef Py_TRACE_REFS
/* if the type object was chained, unchain it first
before overwriting its storage */
if (type->_ob_next) {
_Py_ForgetReference((PyObject*)type);
}
#endif
n_unnamed_members = 0;
for (i = 0; desc->fields[i].name != NULL; ++i)
if (desc->fields[i].name == PyStructSequence_UnnamedField)
n_unnamed_members++;
n_members = i;
memcpy(type, &_struct_sequence_template, sizeof(PyTypeObject));
type->tp_name = desc->name;
type->tp_doc = desc->doc;
type->tp_basicsize = sizeof(PyStructSequence)+
sizeof(PyObject*)*(n_members-1);
type->tp_itemsize = 0;
members = PyMem_NEW(PyMemberDef, n_members-n_unnamed_members+1);
if (members == NULL)
return;
for (i = k = 0; i < n_members; ++i) {
if (desc->fields[i].name == PyStructSequence_UnnamedField)
continue;
members[k].name = desc->fields[i].name;
members[k].type = T_OBJECT;
members[k].offset = offsetof(PyStructSequence, ob_item)
+ i * sizeof(PyObject*);
members[k].flags = READONLY;
members[k].doc = desc->fields[i].doc;
k++;
}
members[k].name = NULL;
type->tp_members = members;
if (PyType_Ready(type) < 0)
return;
Py_INCREF(type);
dict = type->tp_dict;
PyDict_SetItemString(dict, visible_length_key,
PyInt_FromLong((long) desc->n_in_sequence));
PyDict_SetItemString(dict, real_length_key,
PyInt_FromLong((long) n_members));
PyDict_SetItemString(dict, unnamed_fields_key,
PyInt_FromLong((long) n_unnamed_members));
}