Swig and pointers

[Java and Swing]

I've tried sending a email to the swig mailing list 3 times...but it
never seems to get it...not sure what is going on, still looking into
it. Until then...

I now have a C function such as...

int doIt(char *a, MY_DIGIT **digit) {
...
}

so I am trying to figure out how to pass in that "digit" pointer.

My SWIG interface file looks like...

extern int doIt(char *a, MY_DIGIT **digit);
%include cpointer.i
%pointer_functions(MY_DIGIT, md_prt);
%typemap(in) (char *a, MY_DIGIT **argv) {
/* Check if is a list */
if (PyList_Check($input)) {
int i;
$1 = PyList_Size($input);
$2 = (MY_DIGIT **) malloc(($1+1)*sizeof(long *));
for (i = 0; i < $1; i++) {
PyObject *o = PyList_GetItem($input,i);
if (PyString_Check(o))
$2 = PyString_AsString(PyList_GetItem($input,i));
else {
PyErr_SetString(PyExc_TypeError,"list must contain strings");
free($2);
return NULL;
}
}
$2 = 0;
} else {
PyErr_SetString(PyExc_TypeError,"not a list");
return NULL;
}
}

%typemap(freearg) (char *a, MY_DIGIT **argv) {
free((MY_DIGIT *) $2);
}


...from Python I am trying

ptr = []
doIt("blah", ptr)

I thought this was the correct approach as described here:
http://www.swig.org/Doc1.3/SWIGDocumentation.html#Python_nn59

However, python comes back and says "TypeError: argument number 2: a
'MY_DIGIT **' is expected, 'list([])' is received"

...any ideas? Thanks for all the help. The python community has been
great.

 

[Miki Tebeka]

Hello Java,

...
extern int doIt(char *a, MY_DIGIT **digit);
%include cpointer.i
%pointer_functions(MY_DIGIT, md_prt);

Don't you mean md_ptr?

%typemap(in) (char *a, MY_DIGIT **argv) {
/* Check if is a list */
if (PyList_Check($input)) {
int i;
$1 = PyList_Size($input);
$2 = (MY_DIGIT **) malloc(($1+1)*sizeof(long *));
for (i = 0; i < $1; i++) {
PyObject *o = PyList_GetItem($input,i);
if (PyString_Check(o))
$2 = PyString_AsString(PyList_GetItem($input,i));
else {
PyErr_SetString(PyExc_TypeError,"list must contain strings");
free($2);
return NULL;
}
}
$2 = 0;
} else {
PyErr_SetString(PyExc_TypeError,"not a list");
return NULL;
}
}

%typemap(freearg) (char *a, MY_DIGIT **argv) {
free((MY_DIGIT *) $2);
}


..from Python I am trying

ptr = []
doIt("blah", ptr)

I thought this was the correct approach as described here:
http://www.swig.org/Doc1.3/SWIGDocumentation.html#Python_nn59

However, python comes back and says "TypeError: argument number 2: a
'MY_DIGIT **' is expected, 'list([])' is received"

..any ideas?

Didn't check it but from http://www.swig.org/Doc1.3/Library.html it looks
like you need to do:
ptr = new_md_prt()

HTH.
--
------------------------------------------------------------------------
Miki Tebeka <[email protected]>
http://tebeka.bizhat.com
The only difference between children and adults is the price of the toys

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[Java and Swing]

im sorry, why would it be md_ptr? what is md_ptr?

i tried..
%include cpointer.i
%pointer_functions(MY_DIGIT, digit_ptr)

ptr = new_digit_ptr()
doIt("a message", ptr)
....doesnt work..still needs a DIGIT **

 

[Java and Swing]

(reposting, i was just told how I should properly reply via
groups.google.com)

im sorry, why would it be md_ptr? what is md_ptr?

i tried..
%include cpointer.i
%pointer_functions(MY_DIGIT, digit_ptr)

ptr = new_digit_ptr()
doIt("a message", ptr)
....doesnt work..still needs a DIGIT **

Hello Java,

...
extern int doIt(char *a, MY_DIGIT **digit);
%include cpointer.i
%pointer_functions(MY_DIGIT, md_prt);

Don't you mean md_ptr?

%typemap(in) (char *a, MY_DIGIT **argv) {
/* Check if is a list */
if (PyList_Check($input)) {
int i;
$1 = PyList_Size($input);
$2 = (MY_DIGIT **) malloc(($1+1)*sizeof(long *));
for (i = 0; i < $1; i++) {
PyObject *o = PyList_GetItem($input,i);
if (PyString_Check(o))
$2 = PyString_AsString(PyList_GetItem($input,i));
else {
PyErr_SetString(PyExc_TypeError,"list must contain strings");
free($2);
return NULL;
}
}
$2 = 0;
} else {
PyErr_SetString(PyExc_TypeError,"not a list");
return NULL;
}
}

%typemap(freearg) (char *a, MY_DIGIT **argv) {
free((MY_DIGIT *) $2);
}


..from Python I am trying

ptr = []
doIt("blah", ptr)

I thought this was the correct approach as described here:
http://www.swig.org/Doc1.3/SWIGDocumentation.html#Python_nn59

However, python comes back and says "TypeError: argument number 2: a
'MY_DIGIT **' is expected, 'list([])' is received"

..any ideas?

Didn't check it but from http://www.swig.org/Doc1.3/Library.html it looks
like you need to do:
ptr = new_md_prt()

HTH.
--