summaryrefslogtreecommitdiffstats
path: root/Objects/cobject.c
blob: 355421e635216137e97ccf217e78c2c9be0bb7a1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172

/* Wrap void* pointers to be passed between C modules */

#include "Python.h"


/* Declarations for objects of type PyCObject */

typedef void (*destructor1)(void *);
typedef void (*destructor2)(void *, void*);

static int cobject_deprecation_warning(void)
{
    return PyErr_WarnPy3k("CObject type is not supported in 3.x. "
        "Please use capsule objects instead.", 1);
}


PyObject *
PyCObject_FromVoidPtr(void *cobj, void (*destr)(void *))
{
    PyCObject *self;

    if (cobject_deprecation_warning()) {
        return NULL;
    }

    self = PyObject_NEW(PyCObject, &PyCObject_Type);
    if (self == NULL)
        return NULL;
    self->cobject=cobj;
    self->destructor=destr;
    self->desc=NULL;

    return (PyObject *)self;
}

PyObject *
PyCObject_FromVoidPtrAndDesc(void *cobj, void *desc,
                             void (*destr)(void *, void *))
{
    PyCObject *self;

    if (cobject_deprecation_warning()) {
        return NULL;
    }

    if (!desc) {
        PyErr_SetString(PyExc_TypeError,
                        "PyCObject_FromVoidPtrAndDesc called with null"
                        " description");
        return NULL;
    }
    self = PyObject_NEW(PyCObject, &PyCObject_Type);
    if (self == NULL)
        return NULL;
    self->cobject = cobj;
    self->destructor = (destructor1)destr;
    self->desc = desc;

    return (PyObject *)self;
}

void *
PyCObject_AsVoidPtr(PyObject *self)
{
    if (self) {
        if (PyCapsule_CheckExact(self)) {
            const char *name = PyCapsule_GetName(self);
            return (void *)PyCapsule_GetPointer(self, name);
        }
        if (self->ob_type == &PyCObject_Type)
            return ((PyCObject *)self)->cobject;
        PyErr_SetString(PyExc_TypeError,
                        "PyCObject_AsVoidPtr with non-C-object");
    }
    if (!PyErr_Occurred())
        PyErr_SetString(PyExc_TypeError,
                        "PyCObject_AsVoidPtr called with null pointer");
    return NULL;
}

void *
PyCObject_GetDesc(PyObject *self)
{
    if (self) {
        if (self->ob_type == &PyCObject_Type)
            return ((PyCObject *)self)->desc;
        PyErr_SetString(PyExc_TypeError,
                        "PyCObject_GetDesc with non-C-object");
    }
    if (!PyErr_Occurred())
        PyErr_SetString(PyExc_TypeError,
                        "PyCObject_GetDesc called with null pointer");
    return NULL;
}

void *
PyCObject_Import(char *module_name, char *name)
{
    PyObject *m, *c;
    void *r = NULL;

    if ((m = PyImport_ImportModule(module_name))) {
        if ((c = PyObject_GetAttrString(m,name))) {
            r = PyCObject_AsVoidPtr(c);
            Py_DECREF(c);
	}
        Py_DECREF(m);
    }
    return r;
}

int
PyCObject_SetVoidPtr(PyObject *self, void *cobj)
{
    PyCObject* cself = (PyCObject*)self;
    if (cself == NULL || !PyCObject_Check(cself) ||
	cself->destructor != NULL) {
	PyErr_SetString(PyExc_TypeError, 
			"Invalid call to PyCObject_SetVoidPtr");
	return 0;
    }
    cself->cobject = cobj;
    return 1;
}

static void
PyCObject_dealloc(PyCObject *self)
{
    if (self->destructor) {
        if(self->desc)
            ((destructor2)(self->destructor))(self->cobject, self->desc);
        else
            (self->destructor)(self->cobject);
    }
    PyObject_DEL(self);
}


PyDoc_STRVAR(PyCObject_Type__doc__,
"C objects to be exported from one extension module to another\n\
\n\
C objects are used for communication between extension modules.  They\n\
provide a way for an extension module to export a C interface to other\n\
extension modules, so that extension modules can use the Python import\n\
mechanism to link to one another.");

PyTypeObject PyCObject_Type = {
    PyVarObject_HEAD_INIT(&PyType_Type, 0)
    "PyCObject",		/*tp_name*/
    sizeof(PyCObject),		/*tp_basicsize*/
    0,				/*tp_itemsize*/
    /* methods */
    (destructor)PyCObject_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*/
    0,				/*tp_getattro*/
    0,				/*tp_setattro*/
    0,				/*tp_as_buffer*/
    0,				/*tp_flags*/
    PyCObject_Type__doc__	/*tp_doc*/
};