/*

ToDo:

Get rid of the checker (and also the converters) field in PyCFuncPtrObject and

StgDictObject, and replace them by slot functions in StgDictObject.

think about a buffer-like object (memory? bytes?)

Should POINTER(c_char) and POINTER(c_wchar) have a .value property?

What about c_char and c_wchar arrays then?

Add from_mmap, from_file, from_string metaclass methods.

Maybe we can get away with from_file (calls read) and with a from_buffer

method?

And what about the to_mmap, to_file, to_str(?) methods? They would clobber

the namespace, probably. So, functions instead? And we already have memmove...

*/

/*

Name methods, members, getsets

==============================================================================

PyCStructType_Type __new__(), from_address(), __mul__(), from_param()

UnionType_Type __new__(), from_address(), __mul__(), from_param()

PyCPointerType_Type __new__(), from_address(), __mul__(), from_param(), set_type()

PyCArrayType_Type __new__(), from_address(), __mul__(), from_param()

PyCSimpleType_Type __new__(), from_address(), __mul__(), from_param()

PyCData_Type

Struct_Type __new__(), __init__()

PyCPointer_Type __new__(), __init__(), _as_parameter_, contents

PyCArray_Type __new__(), __init__(), _as_parameter_, __get/setitem__(), __len__()

Simple_Type __new__(), __init__(), _as_parameter_

PyCField_Type

PyCStgDict_Type

==============================================================================

class methods

-------------

It has some similarity to the byref() construct compared to pointer()

from_address(addr)

- construct an instance from a given memory block (sharing this memory block)

from_param(obj)

- typecheck and convert a Python object into a C function call parameter

The result may be an instance of the type, or an integer or tuple

(typecode, value[, obj])

instance methods/properties

---------------------------

_as_parameter_

- convert self into a C function call parameter

This is either an integer, or a 3-tuple (typecode, value, obj)

functions

---------

sizeof(cdata)

- return the number of bytes the buffer contains

sizeof(ctype)

- return the number of bytes the buffer of an instance would contain

byref(cdata)

addressof(cdata)

pointer(cdata)

POINTER(ctype)

bytes(cdata)

- return the buffer contents as a sequence of bytes (which is currently a string)

*/

/*

* PyCStgDict_Type

* PyCStructType_Type

* UnionType_Type

* PyCPointerType_Type

* PyCArrayType_Type

* PyCSimpleType_Type

*

* PyCData_Type

* Struct_Type

* Union_Type

* PyCArray_Type

* Simple_Type

* PyCPointer_Type

* PyCField_Type

*

*/

#define PY_SSIZE_T_CLEAN

#include "Python.h"

#include "structmember.h"

#include <ffi.h>

#ifdef MS_WIN32

#include <windows.h>

#include <malloc.h>

#ifndef IS_INTRESOURCE

#define IS_INTRESOURCE(x) (((size_t)(x) >> 16) == 0)

#endif

#else

#include "ctypes_dlfcn.h"

#endif

#include "ctypes.h"

PyObject *PyExc_ArgError = NULL;

/* This dict maps ctypes types to POINTER types */

PyObject *_ctypes_ptrtype_cache = NULL;

static PyTypeObject Simple_Type;

/* a callable object used for unpickling */

static PyObject *_unpickle;

/****************************************************************/

typedef struct {

PyObject_HEAD

PyObject *key;

PyObject *dict;

} DictRemoverObject;

static void

_DictRemover_dealloc(PyObject *myself)

{

DictRemoverObject *self = (DictRemoverObject *)myself;

Py_XDECREF(self->key);

Py_XDECREF(self->dict);

Py_TYPE(self)->tp_free(myself);

}

static PyObject *

_DictRemover_call(PyObject *myself, PyObject *args, PyObject *kw)

{

DictRemoverObject *self = (DictRemoverObject *)myself;

if (self->key && self->dict) {

if (-1 == PyDict_DelItem(self->dict, self->key))

/* XXX Error context */

PyErr_WriteUnraisable(Py_None);

Py_CLEAR(self->key);

Py_CLEAR(self->dict);

}

Py_RETURN_NONE;

}

static PyTypeObject DictRemover_Type = {

PyVarObject_HEAD_INIT(NULL, 0)

"_ctypes.DictRemover", /* tp_name */

sizeof(DictRemoverObject), /* tp_basicsize */

0, /* tp_itemsize */

_DictRemover_dealloc, /* tp_dealloc */

0, /* tp_print */

0, /* tp_getattr */

0, /* tp_setattr */

0, /* tp_reserved */

0, /* tp_repr */

0, /* tp_as_number */

0, /* tp_as_sequence */

0, /* tp_as_mapping */

0, /* tp_hash */

_DictRemover_call, /* tp_call */

0, /* tp_str */

0, /* tp_getattro */

0, /* tp_setattro */

0, /* tp_as_buffer */

/* XXX should participate in GC? */

Py_TPFLAGS_DEFAULT, /* tp_flags */

"deletes a key from a dictionary", /* tp_doc */

0, /* tp_traverse */

0, /* tp_clear */

0, /* tp_richcompare */

0, /* tp_weaklistoffset */

0, /* tp_iter */

0, /* tp_iternext */

0, /* tp_methods */

0, /* 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 */

0, /* tp_new */

0, /* tp_free */

};

int

PyDict_SetItemProxy(PyObject *dict, PyObject *key, PyObject *item)

{

PyObject *obj;

DictRemoverObject *remover;

PyObject *proxy;

int result;

obj = _PyObject_CallNoArg((PyObject *)&DictRemover_Type);

if (obj == NULL)

return -1;

remover = (DictRemoverObject *)obj;

assert(remover->key == NULL);

assert(remover->dict == NULL);

Py_INCREF(key);

remover->key = key;

Py_INCREF(dict);

remover->dict = dict;

proxy = PyWeakref_NewProxy(item, obj);

Py_DECREF(obj);

if (proxy == NULL)

return -1;

result = PyDict_SetItem(dict, key, proxy);

Py_DECREF(proxy);

return result;

}

PyObject *

PyDict_GetItemProxy(PyObject *dict, PyObject *key)

{

PyObject *result;

PyObject *item = PyDict_GetItem(dict, key);

if (item == NULL)

return NULL;

if (!PyWeakref_CheckProxy(item))

return item;

result = PyWeakref_GET_OBJECT(item);

if (result == Py_None)

return NULL;

return result;

}

/******************************************************************/

/*

Allocate a memory block for a pep3118 format string, filled with

a suitable PEP 3118 type code corresponding to the given ctypes

type. Returns NULL on failure, with the error indicator set.

This produces type codes in the standard size mode (cf. struct module),

since the endianness may need to be swapped to a non-native one

later on.

*/

static char *

_ctypes_alloc_format_string_for_type(char code, int big_endian)

{

char *result;

char pep_code = '\0';

switch (code) {

#if SIZEOF_INT == 2

case 'i': pep_code = 'h'; break;

case 'I': pep_code = 'H'; break;

#elif SIZEOF_INT == 4

case 'i': pep_code = 'i'; break;

case 'I': pep_code = 'I'; break;

#elif SIZEOF_INT == 8

case 'i': pep_code = 'q'; break;

case 'I': pep_code = 'Q'; break;

#else

# error SIZEOF_INT has an unexpected value

#endif /* SIZEOF_INT */

#if SIZEOF_LONG == 4

case 'l': pep_code = 'l'; break;

case 'L': pep_code = 'L'; break;

#elif SIZEOF_LONG == 8

case 'l': pep_code = 'q'; break;

case 'L': pep_code = 'Q'; break;

#else

# error SIZEOF_LONG has an unexpected value

#endif /* SIZEOF_LONG */

#if SIZEOF__BOOL == 1

case '?': pep_code = '?'; break;

#elif SIZEOF__BOOL == 2

case '?': pep_code = 'H'; break;

#elif SIZEOF__BOOL == 4

case '?': pep_code = 'L'; break;

#elif SIZEOF__BOOL == 8

case '?': pep_code = 'Q'; break;

#else

# error SIZEOF__BOOL has an unexpected value

#endif /* SIZEOF__BOOL */

default:

/* The standard-size code is the same as the ctypes one */

pep_code = code;

break;

}

result = PyMem_Malloc(3);

if (result == NULL) {

PyErr_NoMemory();

return NULL;

}

result[0] = big_endian ? '>' : '<';

result[1] = pep_code;

result[2] = '\0';

return result;

}

/*

Allocate a memory block for a pep3118 format string, copy prefix (if

non-null) and suffix into it. Returns NULL on failure, with the error

indicator set. If called with a suffix of NULL the error indicator must

already be set.

*/

char *

_ctypes_alloc_format_string(const char *prefix, const char *suffix)

{

size_t len;

char *result;

if (suffix == NULL) {

assert(PyErr_Occurred());

return NULL;

}

len = strlen(suffix);

if (prefix)

len += strlen(prefix);

result = PyMem_Malloc(len + 1);

if (result == NULL) {

PyErr_NoMemory();

return NULL;

}

if (prefix)

strcpy(result, prefix);

else

result[0] = '\0';

strcat(result, suffix);

return result;

}

/*

Allocate a memory block for a pep3118 format string, adding

the given prefix (if non-null), an additional shape prefix, and a suffix.

Returns NULL on failure, with the error indicator set. If called with

a suffix of NULL the error indicator must already be set.

*/

char *

_ctypes_alloc_format_string_with_shape(int ndim, const Py_ssize_t *shape,

const char *prefix, const char *suffix)

{

char *new_prefix;

char *result;

char buf[32];

Py_ssize_t prefix_len;

int k;

prefix_len = 32 * ndim + 3;

if (prefix)

prefix_len += strlen(prefix);

new_prefix = PyMem_Malloc(prefix_len);

if (new_prefix == NULL) {

PyErr_NoMemory();

return NULL;

}

new_prefix[0] = '\0';

if (prefix)

strcpy(new_prefix, prefix);

if (ndim > 0) {

/* Add the prefix "(shape[0],shape[1],...,shape[ndim-1])" */

strcat(new_prefix, "(");

for (k = 0; k < ndim; ++k) {

if (k < ndim-1) {

sprintf(buf, "%"PY_FORMAT_SIZE_T"d,", shape[k]);

} else {

sprintf(buf, "%"PY_FORMAT_SIZE_T"d)", shape[k]);

}

strcat(new_prefix, buf);

}

}

result = _ctypes_alloc_format_string(new_prefix, suffix);

PyMem_Free(new_prefix);

return result;

}

/*

PyCStructType_Type - a meta type/class. Creating a new class using this one as

__metaclass__ will call the constructor StructUnionType_new. It replaces the

tp_dict member with a new instance of StgDict, and initializes the C

accessible fields somehow.

*/

static PyCArgObject *

StructUnionType_paramfunc(CDataObject *self)

{

PyCArgObject *parg;

StgDictObject *stgdict;

parg = PyCArgObject_new();

if (parg == NULL)

return NULL;

parg->tag = 'V';

stgdict = PyObject_stgdict((PyObject *)self);

assert(stgdict); /* Cannot be NULL for structure/union instances */

parg->pffi_type = &stgdict->ffi_type_pointer;

/* For structure parameters (by value), parg->value doesn't contain the structure

data itself, instead parg->value.p *points* to the structure's data

See also _ctypes.c, function _call_function_pointer().

*/

parg->value.p = self->b_ptr;

parg->size = self->b_size;

Py_INCREF(self);

parg->obj = (PyObject *)self;

return parg;

}

static PyObject *

StructUnionType_new(PyTypeObject *type, PyObject *args, PyObject *kwds, int isStruct)

{

PyTypeObject *result;

PyObject *fields;

StgDictObject *dict;

/* create the new instance (which is a class,

since we are a metatype!) */

result = (PyTypeObject *)PyType_Type.tp_new(type, args, kwds);

if (!result)

return NULL;

/* keep this for bw compatibility */

if (PyDict_GetItemString(result->tp_dict, "_abstract_"))

return (PyObject *)result;

dict = (StgDictObject *)_PyObject_CallNoArg((PyObject *)&PyCStgDict_Type);

if (!dict) {

Py_DECREF(result);

return NULL;

}

if (!isStruct) {

dict->flags |= TYPEFLAG_HASUNION;

}

/* replace the class dict by our updated stgdict, which holds info

about storage requirements of the instances */

if (-1 == PyDict_Update((PyObject *)dict, result->tp_dict)) {

Py_DECREF(result);

Py_DECREF((PyObject *)dict);

return NULL;

}

Py_SETREF(result->tp_dict, (PyObject *)dict);

dict->format = _ctypes_alloc_format_string(NULL, "B");

if (dict->format == NULL) {

Py_DECREF(result);

return NULL;

}

dict->paramfunc = StructUnionType_paramfunc;

fields = PyDict_GetItemString((PyObject *)dict, "_fields_");

if (!fields) {

StgDictObject *basedict = PyType_stgdict((PyObject *)result->tp_base);

if (basedict == NULL)

return (PyObject *)result;

/* copy base dict */

if (-1 == PyCStgDict_clone(dict, basedict)) {

Py_DECREF(result);

return NULL;

}

dict->flags &= ~DICTFLAG_FINAL; /* clear the 'final' flag in the subclass dict */

basedict->flags |= DICTFLAG_FINAL; /* set the 'final' flag in the baseclass dict */

return (PyObject *)result;

}

if (-1 == PyObject_SetAttrString((PyObject *)result, "_fields_", fields)) {

Py_DECREF(result);

return NULL;

}

return (PyObject *)result;

}

static PyObject *

PyCStructType_new(PyTypeObject *type, PyObject *args, PyObject *kwds)

{

return StructUnionType_new(type, args, kwds, 1);

}

static PyObject *

UnionType_new(PyTypeObject *type, PyObject *args, PyObject *kwds)

{

return StructUnionType_new(type, args, kwds, 0);

}

static const char from_address_doc[] =

"C.from_address(integer) -> C instance\naccess a C instance at the specified address";

static PyObject *

CDataType_from_address(PyObject *type, PyObject *value)

{

void *buf;

if (!PyLong_Check(value)) {

PyErr_SetString(PyExc_TypeError,

"integer expected");

return NULL;

}

buf = (void *)PyLong_AsVoidPtr(value);

if (PyErr_Occurred())

return NULL;

return PyCData_AtAddress(type, buf);

}

static const char from_buffer_doc[] =

"C.from_buffer(object, offset=0) -> C instance\ncreate a C instance from a writeable buffer";

static int

KeepRef(CDataObject *target, Py_ssize_t index, PyObject *keep);

static PyObject *

CDataType_from_buffer(PyObject *type, PyObject *args)

{

PyObject *obj;

PyObject *mv;

PyObject *result;

Py_buffer *buffer;

Py_ssize_t offset = 0;

StgDictObject *dict = PyType_stgdict(type);

if (!dict) {

PyErr_SetString(PyExc_TypeError, "abstract class");

return NULL;

}

if (!PyArg_ParseTuple(args, "O|n:from_buffer", &obj, &offset))

return NULL;

mv = PyMemoryView_FromObject(obj);

if (mv == NULL)

return NULL;

buffer = PyMemoryView_GET_BUFFER(mv);

if (buffer->readonly) {

PyErr_SetString(PyExc_TypeError,

"underlying buffer is not writable");

Py_DECREF(mv);

return NULL;

}

if (!PyBuffer_IsContiguous(buffer, 'C')) {

PyErr_SetString(PyExc_TypeError,

"underlying buffer is not C contiguous");

Py_DECREF(mv);

return NULL;

}

if (offset < 0) {

PyErr_SetString(PyExc_ValueError,

"offset cannot be negative");

Py_DECREF(mv);

return NULL;

}

if (dict->size > buffer->len - offset) {

PyErr_Format(PyExc_ValueError,

"Buffer size too small "

"(%zd instead of at least %zd bytes)",

buffer->len, dict->size + offset);

Py_DECREF(mv);

return NULL;

}

result = PyCData_AtAddress(type, (char *)buffer->buf + offset);

if (result == NULL) {

Py_DECREF(mv);

return NULL;

}

if (-1 == KeepRef((CDataObject *)result, -1, mv)) {

Py_DECREF(result);

return NULL;

}

return result;

}

static const char from_buffer_copy_doc[] =

"C.from_buffer_copy(object, offset=0) -> C instance\ncreate a C instance from a readable buffer";

static PyObject *

GenericPyCData_new(PyTypeObject *type, PyObject *args, PyObject *kwds);

static PyObject *

CDataType_from_buffer_copy(PyObject *type, PyObject *args)

{

Py_buffer buffer;

Py_ssize_t offset = 0;

PyObject *result;

StgDictObject *dict = PyType_stgdict(type);

if (!dict) {

PyErr_SetString(PyExc_TypeError, "abstract class");

return NULL;

}

if (!PyArg_ParseTuple(args, "y*|n:from_buffer_copy", &buffer, &offset))

return NULL;

if (offset < 0) {

PyErr_SetString(PyExc_ValueError,

"offset cannot be negative");

PyBuffer_Release(&buffer);

return NULL;

}

if (dict->size > buffer.len - offset) {

PyErr_Format(PyExc_ValueError,

"Buffer size too small (%zd instead of at least %zd bytes)",

buffer.len, dict->size + offset);

PyBuffer_Release(&buffer);

return NULL;

}

result = GenericPyCData_new((PyTypeObject *)type, NULL, NULL);

if (result != NULL) {

memcpy(((CDataObject *)result)->b_ptr,

(char *)buffer.buf + offset, dict->size);

}

PyBuffer_Release(&buffer);

return result;

}

static const char in_dll_doc[] =

"C.in_dll(dll, name) -> C instance\naccess a C instance in a dll";

static PyObject *

CDataType_in_dll(PyObject *type, PyObject *args)

{

PyObject *dll;

char *name;

PyObject *obj;

void *handle;

void *address;

if (!PyArg_ParseTuple(args, "Os:in_dll", &dll, &name))

return NULL;

obj = PyObject_GetAttrString(dll, "_handle");

if (!obj)

return NULL;

if (!PyLong_Check(obj)) {

PyErr_SetString(PyExc_TypeError,

"the _handle attribute of the second argument must be an integer");

Py_DECREF(obj);

return NULL;

}

handle = (void *)PyLong_AsVoidPtr(obj);

Py_DECREF(obj);

if (PyErr_Occurred()) {

PyErr_SetString(PyExc_ValueError,

"could not convert the _handle attribute to a pointer");

return NULL;

}

#ifdef MS_WIN32

address = (void *)GetProcAddress(handle, name);

if (!address) {

PyErr_Format(PyExc_ValueError,

"symbol '%s' not found",

name);

return NULL;

}

#else

address = (void *)ctypes_dlsym(handle, name);

if (!address) {

#ifdef __CYGWIN__

/* dlerror() isn't very helpful on cygwin */

PyErr_Format(PyExc_ValueError,

"symbol '%s' not found",

name);

#else

PyErr_SetString(PyExc_ValueError, ctypes_dlerror());

#endif

return NULL;

}

#endif

return PyCData_AtAddress(type, address);

}

static const char from_param_doc[] =

"Convert a Python object into a function call parameter.";

static PyObject *

CDataType_from_param(PyObject *type, PyObject *value)

{

PyObject *as_parameter;

int res = PyObject_IsInstance(value, type);

if (res == -1)

return NULL;

if (res) {

Py_INCREF(value);

return value;

}

if (PyCArg_CheckExact(value)) {

PyCArgObject *p = (PyCArgObject *)value;

PyObject *ob = p->obj;

const char *ob_name;

StgDictObject *dict;

dict = PyType_stgdict(type);

/* If we got a PyCArgObject, we must check if the object packed in it

is an instance of the type's dict->proto */

if(dict && ob) {

res = PyObject_IsInstance(ob, dict->proto);

if (res == -1)

return NULL;

if (res) {

Py_INCREF(value);

return value;

}

}

ob_name = (ob) ? Py_TYPE(ob)->tp_name : "???";

PyErr_Format(PyExc_TypeError,

"expected %s instance instead of pointer to %s",

((PyTypeObject *)type)->tp_name, ob_name);

return NULL;

}

as_parameter = PyObject_GetAttrString(value, "_as_parameter_");

if (as_parameter) {

value = CDataType_from_param(type, as_parameter);

Py_DECREF(as_parameter);

return value;

}

PyErr_Format(PyExc_TypeError,

"expected %s instance instead of %s",

((PyTypeObject *)type)->tp_name,

Py_TYPE(value)->tp_name);

return NULL;

}

static PyMethodDef CDataType_methods[] = {

{ "from_param", CDataType_from_param, METH_O, from_param_doc },

{ "from_address", CDataType_from_address, METH_O, from_address_doc },

{ "from_buffer", CDataType_from_buffer, METH_VARARGS, from_buffer_doc, },

{ "from_buffer_copy", CDataType_from_buffer_copy, METH_VARARGS, from_buffer_copy_doc, },

{ "in_dll", CDataType_in_dll, METH_VARARGS, in_dll_doc },

{ NULL, NULL },

};

static PyObject *

CDataType_repeat(PyObject *self, Py_ssize_t length)

{

if (length < 0)

return PyErr_Format(PyExc_ValueError,

"Array length must be >= 0, not %zd",

length);

return PyCArrayType_from_ctype(self, length);

}

static PySequenceMethods CDataType_as_sequence = {

0, /* inquiry sq_length; */

0, /* binaryfunc sq_concat; */

CDataType_repeat, /* intargfunc sq_repeat; */

0, /* intargfunc sq_item; */

0, /* intintargfunc sq_slice; */

0, /* intobjargproc sq_ass_item; */

0, /* intintobjargproc sq_ass_slice; */

0, /* objobjproc sq_contains; */

0, /* binaryfunc sq_inplace_concat; */

0, /* intargfunc sq_inplace_repeat; */

};

static int

CDataType_clear(PyTypeObject *self)

{

StgDictObject *dict = PyType_stgdict((PyObject *)self);

if (dict)

Py_CLEAR(dict->proto);

return PyType_Type.tp_clear((PyObject *)self);

}

static int

CDataType_traverse(PyTypeObject *self, visitproc visit, void *arg)

{

StgDictObject *dict = PyType_stgdict((PyObject *)self);

if (dict)

Py_VISIT(dict->proto);

return PyType_Type.tp_traverse((PyObject *)self, visit, arg);

}

static int

PyCStructType_setattro(PyObject *self, PyObject *key, PyObject *value)

{

/* XXX Should we disallow deleting _fields_? */

if (-1 == PyType_Type.tp_setattro(self, key, value))

return -1;

if (value && PyUnicode_Check(key) &&

_PyUnicode_EqualToASCIIString(key, "_fields_"))

return PyCStructUnionType_update_stgdict(self, value, 1);

return 0;

}

static int

UnionType_setattro(PyObject *self, PyObject *key, PyObject *value)

{

/* XXX Should we disallow deleting _fields_? */

if (-1 == PyObject_GenericSetAttr(self, key, value))

return -1;

if (PyUnicode_Check(key) &&

_PyUnicode_EqualToASCIIString(key, "_fields_"))

return PyCStructUnionType_update_stgdict(self, value, 0);

return 0;

}

PyTypeObject PyCStructType_Type = {

PyVarObject_HEAD_INIT(NULL, 0)

"_ctypes.PyCStructType", /* tp_name */

0, /* tp_basicsize */

0, /* tp_itemsize */

0, /* tp_dealloc */

0, /* tp_print */

0, /* tp_getattr */

0, /* tp_setattr */

0, /* tp_reserved */

0, /* tp_repr */

0, /* tp_as_number */

&CDataType_as_sequence, /* tp_as_sequence */

0, /* tp_as_mapping */

0, /* tp_hash */

0, /* tp_call */

0, /* tp_str */

0, /* tp_getattro */

PyCStructType_setattro, /* tp_setattro */

0, /* tp_as_buffer */

Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, /* tp_flags */

"metatype for the CData Objects", /* tp_doc */

(traverseproc)CDataType_traverse, /* tp_traverse */

(inquiry)CDataType_clear, /* tp_clear */

0, /* tp_richcompare */

0, /* tp_weaklistoffset */

0, /* tp_iter */

0, /* tp_iternext */

CDataType_methods, /* tp_methods */

0, /* 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 */

PyCStructType_new, /* tp_new */

0, /* tp_free */

};

static PyTypeObject UnionType_Type = {

PyVarObject_HEAD_INIT(NULL, 0)

"_ctypes.UnionType", /* tp_name */

0, /* tp_basicsize */

0, /* tp_itemsize */

0, /* tp_dealloc */

0, /* tp_print */

0, /* tp_getattr */

0, /* tp_setattr */

0, /* tp_reserved */

0, /* tp_repr */

0, /* tp_as_number */

&CDataType_as_sequence, /* tp_as_sequence */

0, /* tp_as_mapping */

0, /* tp_hash */

0, /* tp_call */

0, /* tp_str */

0, /* tp_getattro */

UnionType_setattro, /* tp_setattro */

0, /* tp_as_buffer */

Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, /* tp_flags */

"metatype for the CData Objects", /* tp_doc */

(traverseproc)CDataType_traverse, /* tp_traverse */

(inquiry)CDataType_clear, /* tp_clear */

0, /* tp_richcompare */

0, /* tp_weaklistoffset */

0, /* tp_iter */

0, /* tp_iternext */

CDataType_methods, /* tp_methods */

0, /* 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 */

UnionType_new, /* tp_new */

0, /* tp_free */

};

/******************************************************************/

/*

The PyCPointerType_Type metaclass must ensure that the subclass of Pointer can be

created. It must check for a _type_ attribute in the class. Since are no

runtime created properties, a CField is probably *not* needed ?

class IntPointer(Pointer):

_type_ = "i"

The PyCPointer_Type provides the functionality: a contents method/property, a

size property/method, and the sequence protocol.

*/

static int

PyCPointerType_SetProto(StgDictObject *stgdict, PyObject *proto)

{

if (!proto || !PyType_Check(proto)) {

PyErr_SetString(PyExc_TypeError,

"_type_ must be a type");

return -1;

}

if (!PyType_stgdict(proto)) {

PyErr_SetString(PyExc_TypeError,

"_type_ must have storage info");

return -1;

}

Py_INCREF(proto);

Py_XSETREF(stgdict->proto, proto);

return 0;

}

static PyCArgObject *

PyCPointerType_paramfunc(CDataObject *self)

{

PyCArgObject *parg;

parg = PyCArgObject_new();

if (parg == NULL)

return NULL;

parg->tag = 'P';

parg->pffi_type = &ffi_type_pointer;

Py_INCREF(self);

parg->obj = (PyObject *)self;

parg->value.p = *(void **)self->b_ptr;

return parg;

}

static PyObject *

PyCPointerType_new(PyTypeObject *type, PyObject *args, PyObject *kwds)

{

PyTypeObject *result;

StgDictObject *stgdict;

PyObject *proto;

PyObject *typedict;

typedict = PyTuple_GetItem(args, 2);

if (!typedict)

return NULL;

/*

stgdict items size, align, length contain info about pointers itself,

stgdict->proto has info about the pointed to type!

*/

stgdict = (StgDictObject *)PyObject_CallObject(

(PyObject *)&PyCStgDict_Type, NULL);

if (!stgdict)

return NULL;

stgdict->size = sizeof(void *);

stgdict->align = _ctypes_get_fielddesc("P")->pffi_type->alignment;

stgdict->length = 1;

stgdict->ffi_type_pointer = ffi_type_pointer;

stgdict->paramfunc = PyCPointerType_paramfunc;

stgdict->flags |= TYPEFLAG_ISPOINTER;

proto = PyDict_GetItemString(typedict, "_type_"); /* Borrowed ref */

if (proto && -1 == PyCPointerType_SetProto(stgdict, proto)) {

Py_DECREF((PyObject *)stgdict);

return NULL;

}

if (proto) {

StgDictObject *itemdict = PyType_stgdict(proto);

const char *current_format;

/* PyCPointerType_SetProto has verified proto has a stgdict. */

assert(itemdict);