Hello :)
The result of various incompatibiliti es has left me needing to somehow
extract the address that a null pointer is pointing to with the null
pointer being exposed to python via PyCObject_FromV oidPtr
the code that creates the PyCObject is as follows:
tmp = PyCObject_FromV oidPtr (info.info.x11. display, NULL);
PyDict_SetItemS tring (dict, "display", tmp);
Py_DECREF (tmp);
which is exposed to python via a dictionary (the 'display' key). python
identifies that its a PyCObject but doesn't give any way to expose the
functionality. Essentially I am after the address that the void pointer
'info.info.x11. display' points to (as a long type)
As far as I can tell ctypes will only expose the pyObject type to me and
not actually let me deal with the data I am after, but being rather new
to ctypes I'm not sure weather this is correct.
--
Gord Allott (go********@gma il.com)
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On Oct 10, 5:24*am, Gordon Allott <gordall...@gma il.comwrote:
Hello :)
The result of various incompatibiliti es has left me needing to somehow
extract the address that a null pointer is pointing to with the null
pointer being exposed to python via PyCObject_FromV oidPtr
the code that creates the PyCObject is as follows:
* * tmp = PyCObject_FromV oidPtr (info.info.x11. display, NULL);
* * PyDict_SetItemS tring (dict, "display", tmp);
* * Py_DECREF (tmp);
Did you try:
tmp= PyLong_FromLong ( ( long ) info.info.x11.d isplay );
PyDict_SetItemS tring (dict, "display", tmp);
Py_DECREF (tmp);
Or also try:
PyCObject_AsVoi dPtr( tmp );
Aaron "Castironpi " Brady wrote:
Did you try:
tmp= PyLong_FromLong ( ( long ) info.info.x11.d isplay );
PyDict_SetItemS tring (dict, "display", tmp);
Py_DECREF (tmp);
Or also try:
PyCObject_AsVoi dPtr( tmp );
--
http://mail.python.org/mailman/listinfo/python-list
the problem is that I can't edit the C code - well I can and might
submit a patch to the project but I also need a solution that works from
the python side of things.
--
Gord Allott (go********@gma il.com)
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On Oct 10, 12:04*pm, Gordon Allott <gordall...@gma il.comwrote:
Aaron "Castironpi " Brady wrote:
Did you try:
tmp= PyLong_FromLong ( ( long ) info.info.x11.d isplay );
PyDict_SetItemS tring (dict, "display", tmp);
Py_DECREF (tmp);
Or also try:
PyCObject_AsVoi dPtr( tmp );
--
http://mail.python.org/mailman/listinfo/python-list
the problem is that I can't edit the C code - well I can and might
submit a patch to the project but I also need a solution that works from
the python side of things.
I see. If I understand, you have a PyCObject in a dictionary.
Look at the 'ctypes' module and try calling PyCObject_AsVoi dPtr. Its
return type should be 'c_void_p', and you can use 'result.value' to
get the original pointer.
Aaron "Castironpi " Brady wrote:
I see. If I understand, you have a PyCObject in a dictionary.
Look at the 'ctypes' module and try calling PyCObject_AsVoi dPtr. Its
return type should be 'c_void_p', and you can use 'result.value' to
get the original pointer.
--
http://mail.python.org/mailman/listinfo/python-list
I have a hard time following that, if using ctypes you used PyDLL to
call PyCObject_AsVoi dPtr on the PyCObject I already have surely it would
give me back a pointer (void for sake of simplicity) but it would be a
pointer to a new PyCObject and thus calling result.value on it would
only return the memory address of the new PyCObject?
--
Gord Allott (go********@gma il.com)
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On Oct 10, 4:16*pm, Gordon Allott <gordall...@gma il.comwrote:
Aaron "Castironpi " Brady wrote:
I see. *If I understand, you have a PyCObject in a dictionary.
Look at the 'ctypes' module and try calling PyCObject_AsVoi dPtr. *Its
return type should be 'c_void_p', and you can use 'result.value' to
get the original pointer.
--
http://mail.python.org/mailman/listinfo/python-list
I have a hard time following that, if using ctypes you used PyDLL to
call PyCObject_AsVoi dPtr on the PyCObject I already have surely it would
*give me back a pointer (void for sake of simplicity) but it would be a
pointer to a new PyCObject and thus calling result.value on it would
only return the memory address of the new PyCObject?
--
Gord Allott (gordall...@gma il.com)
*signature.asc
< 1KViewDownload
Yes, well said. But no, not true, not necessarily. You can choose/
change return types with your code. If the call is defined already
and you can't change the return, just define a new one that returns
long.
Aaron "Castironpi " Brady wrote:
Yes, well said. But no, not true, not necessarily. You can choose/
change return types with your code. If the call is defined already
and you can't change the return, just define a new one that returns
long.
--
http://mail.python.org/mailman/listinfo/python-list
the problem is that the pointer or long or whatever it is thats returned
won't be the data I am after. the code for PyCObject_FromV oidPtr is as
follows:
PyObject *
PyCObject_FromV oidPtr(void *cobj, void (*destr)(void *))
{
PyCObject *self;
self = PyObject_NEW(Py CObject, &PyCObject_Type );
if (self == NULL)
return NULL;
self->cobject=cobj ;
self->destructor=des tr;
self->desc=NULL;
return (PyObject *)self;
}
it obviously creates a new PyObject and returns that, which has already
happened once (the address I am after is passed to python via
PyCObject_FromV oidPtr(adress_i _am_after, NULL), doing that puts the
address I am after into the .cobject attribute of a new pyobject
structure and passes that to the python script via the 'display' key in
a dictionary.
If I were to then take the pycobject in this display key and pass it via
ctypes into PyCObject_FromV oidPtr it would simply create a new pycobject
and put a pointer to the old pycobject in the new pycobject's .cobject
attribute. it just means that I am getting further and further away from
where I want to be surely? if I were to take the current pointer at this
stage, to get to the address I actually want in C it would have to
follow something along the lines of
long address_i_want = (long)(new_pyco bj->cobject->cobject);
What would be great is if there is some easy simple way of accessing the
.cobject attribute of the first pycobject thats passed via the
dictionary to python.
--
Gord Allott (go********@gma il.com)
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On Oct 10, 7:59*pm, Gordon Allott <gordall...@gma il.comwrote:
Aaron "Castironpi " Brady wrote:
Yes, well said. *But no, not true, not necessarily. *You can choose/
change return types with your code. *If the call is defined already
and you can't change the return, just define a new one that returns
long.
--
http://mail.python.org/mailman/listinfo/python-list
the problem is that the pointer or long or whatever it is thats returned
won't be the data I am after. the code for PyCObject_FromV oidPtr is as
follows:
PyObject *
PyCObject_FromV oidPtr(void *cobj, void (*destr)(void *))
{
* * PyCObject *self;
* * self = PyObject_NEW(Py CObject, &PyCObject_Type );
* * if (self == NULL)
* * * * return NULL;
* * self->cobject=cobj ;
* * self->destructor=des tr;
* * self->desc=NULL;
* * return (PyObject *)self;
}
it obviously creates a new PyObject and returns that, which has already
happened once (the address I am after is passed to python via
PyCObject_FromV oidPtr(adress_i _am_after, NULL), doing that puts the
address I am after into the .cobject attribute of a new pyobject
structure and passes that to the python script via the 'display' key in
a dictionary.
If I were to then take the pycobject in this display key and pass it via
ctypes into PyCObject_FromV oidPtr it would simply create a new pycobject
*and put a pointer to the old pycobject in the new pycobject's .cobject
attribute. it just means that I am getting further and further away from
where I want to be surely? if I were to take the current pointer at this
stage, to get to the address I actually want in C it would have to
follow something along the lines of
long address_i_want = (long)(new_pyco bj->cobject->cobject);
What would be great is if there is some easy simple way of accessing the
.cobject attribute of the first pycobject thats passed via the
dictionary to python.
--
Gord Allott (gordall...@gma il.com)
*signature.asc
< 1KViewDownload
You are hard to follow. There is the 'cast' function, which I've had
some success with, even in adding pointers and offsets. It took a
look at the code for it though, and calling an undocumented version of
it. I can post that later if you don't have luck the same. You can
write extension modules to do that as well, and there's always a
Google search which personally I forget half the time too. Last, you
haven't mentioned an attempt with PyCObject_AsVoi dPtr yet:
void* PyCObject_AsVoi dPtr(PyObject* self)
Return the object void * that the PyCObject self was created with.
Where does that get you?
Aaron "Castironpi " Brady wrote:
You are hard to follow. There is the 'cast' function, which I've had
some success with, even in adding pointers and offsets. It took a
look at the code for it though, and calling an undocumented version of
it. I can post that later if you don't have luck the same. You can
write extension modules to do that as well, and there's always a
Google search which personally I forget half the time too. Last, you
haven't mentioned an attempt with PyCObject_AsVoi dPtr yet:
void* PyCObject_AsVoi dPtr(PyObject* self)
Return the object void * that the PyCObject self was created with.
Where does that get you?
--
http://mail.python.org/mailman/listinfo/python-list
sorry yes you were right, I was reading PyCObject_AsVoi dPtr as
PyCObject_FromV oidPtr :)
using AsVoidPtr is a little confusing, this is the code I am using:
display = pygame.display. get_wm_info()['display']
pyobj = py_object(displ ay)
ref = pointer(pyobj)
print pythonapi.PyCOb ject_AsVoidPtr( ref)
it produces the following traceback:
Traceback (most recent call last):
File "pygametest.py" , line 125, in <module>
app = PyGameOGREApp()
File "pygametest.py" , line 33, in __init__
self._createWin dow(width, height, fullscreen)
File "pygametest.py" , line 64, in _createWindow
print pythonapi.PyCOb ject_AsVoidPtr( ref)
TypeError: PyCObject_AsVoi dPtr with non-C-object
- I think that's because its a pointer to the ctypes py_object() rather
than the PyCObject we are dealing with but I have no idea how to create
a pointer to that.
--
Gord Allott (go********@gma il.com)
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On Oct 10, 10:54*pm, Gordon Allott <gordall...@gma il.comwrote:
Aaron "Castironpi " Brady wrote:
snip
*Last, you
haven't mentioned an attempt with PyCObject_AsVoi dPtr yet:
void* PyCObject_AsVoi dPtr(PyObject* self)
* * Return the object void * that the PyCObject self was created with.
Where does that get you?
--
http://mail.python.org/mailman/listinfo/python-list
sorry yes you were right, I was reading PyCObject_AsVoi dPtr as
PyCObject_FromV oidPtr :)
using AsVoidPtr is a little confusing, this is the code I am using:
* * * * display = pygame.display. get_wm_info()['display']
* * * * pyobj = py_object(displ ay)
* * * * ref = pointer(pyobj)
* * * * print pythonapi.PyCOb ject_AsVoidPtr( ref)
it produces the following traceback:
Traceback (most recent call last):
* File "pygametest.py" , line 125, in <module>
* * app = PyGameOGREApp()
* File "pygametest.py" , line 33, in __init__
* * self._createWin dow(width, height, fullscreen)
* File "pygametest.py" , line 64, in _createWindow
* * print pythonapi.PyCOb ject_AsVoidPtr( ref)
TypeError: PyCObject_AsVoi dPtr with non-C-object
- I think that's because its a pointer to the ctypes py_object() rather
than the PyCObject we are dealing with but I have no idea how to create
a pointer to that.
My pygame install just returns an integer in get_wm_info. Take a
look:
>>pygame.displa y.get_wm_info()
{'window': 1180066, 'hglrc': 0}
>>pygame.displa y.get_wm_info()['window']
1180066
>>ctypes.c_void _p( _ )
c_void_p(118006 6)
You're suggesting yours looks like this:
>>pygame.displa y.get_wm_info()
{ ... 'display': ctypes.py_objec t( 1180066 ), ... }
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