/* 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)

{

int i, size;

size = REAL_SIZE(obj);

for (i = 0; i < size; ++i) {

Py_XDECREF(obj->ob_item[i]);

}

PyObject_Del(obj);

}

static int

structseq_length(PyStructSequence *obj)

{

return VISIBLE_SIZE(obj);

}

static PyObject*

structseq_item(PyStructSequence *obj, int 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, int low, int high)

{

PyTupleObject *np;

int 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;

int 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 %d-sequence (%d-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 %d-sequence (%d-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 %d-sequence (%d-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, int 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);

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);

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;

long 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 = {

(inquiry)structseq_length,

(binaryfunc)structseq_concat, /* sq_concat */

(intargfunc)structseq_repeat, /* sq_repeat */

(intargfunc)structseq_item, /* sq_item */

(intintargfunc)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 */

(hashfunc)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;

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));

}