Re: [Swig-user] %apply not working with pointers

[Javier D. C. <jav...@fo...>]

More information, the output with debug option:

swig/aj_helper.i:21: Searching for a suitable 'in' typemap for: uint32_t *OUTPUT
  Looking for: uint32_t *OUTPUT
  Looking for: uint32_t *
  Looking for: SWIGTYPE *OUTPUT
  Looking for: SWIGTYPE *
  Using: %typemap(in) SWIGTYPE *

in theory, acording to the docs, OUTPUT should be mapped to out
typemap, shouldn't it?

Just in case someone wonders, I included typemaps.in in the higher level header


Javier Domingo Cansino
Research & Development Junior Engineer
Fon Labs Workgroup, Getxo - Spain.


On Fri, Sep 19, 2014 at 12:54 PM, Javier Domingo Cansino
<jav...@fo...> wrote:
> Seems that this is caused because SWIG does return by reference
> different from what I thought.
>
> Anyone knows how to override just one function to mark a function's
> argument as OUTPUT using
> http://www.swig.org/Doc3.0/SWIGDocumentation.html#Arguments_nn5 but I
> don't know how to make it in a bigger file.
>
> I have tried copying the header file, etc. but nothing worked. My
> header file atm is:
>
> =====
> %include aj_status.i
> %include aj_bus.i
>
> %{
> AJ_EXPORT AJ_Status AJ_StartClient(AJ_BusAttachment* bus,
>                          const char* daemonName,
>                          uint32_t timeout,
>                          uint8_t connected,
>                          const char* name,
>                          uint16_t port,
>                          uint32_t* OUTPUT,
>                          const AJ_SessionOpts* opts);
> %}
>
> AJ_EXPORT AJ_Status AJ_StartClient(AJ_BusAttachment* bus,
>                          const char* daemonName,
>                          uint32_t timeout,
>                          uint8_t connected,
>                          const char* name,
>                          uint16_t port,
>                          uint32_t* OUTPUT,
>                          const AJ_SessionOpts* opts);
>
>
> %{
> #include "aj_helper.h"
> %}
>
> %include aj_helper.h
> =====
>
> But doesn't seem to get overriden
>
> Javier Domingo Cansino
> Research & Development Junior Engineer
> Fon Labs Workgroup, Getxo - Spain.
>
>
> On Fri, Sep 12, 2014 at 3:44 PM, Javier Domingo Cansino
> <jav...@fo...> wrote:
>> Hi,
>>
>> I am struggling against how to map different well known and C standard
>> data types, such as uint32, etc. I have found that %apply unsigned
>> long {uint32_t} works like a charm, and maps correctly values.
>>
>> The problem comes when I want to use a uint32_t *. In that case, SWIG
>> doesn't interpret it correctly.
>>
>> The output error message is (once modified the SWIG_ConvertPtr):
>> ```
>> No type cast needed
>> sobj
>> Argument 7 about to be parsed
>> Traceback (most recent call last):
>>   File "test.py", line 15, in <module>
>>     None)
>> TypeError: in method 'AJ_StartClient', argument 7 of type 'uint32_t *'
>> No type cast needed
>> sobj
>> ```
>>
>> The code generated is like this:
>> ```
>>   res7 = SWIG_ConvertPtr(obj6, &argp7,SWIGTYPE_p_uint32_t, 0 |  0 );
>>   if (!SWIG_IsOK(res7)) {
>>     SWIG_exception_fail(SWIG_ArgError(res7), "in method '"
>> "AJ_StartClient" "', argument " "7"" of type '" "uint32_t *""'");
>>   }
>>   arg7 = (uint32_t *)(argp7);
>> ```
>>
>> If I follow the code execution through SWIG_ConvertPtr() and it
>> doesn't seem to qualify for (!SWIG_IsOK(res7)), so I am unable to know
>> what if failing here:
>> ```
>> SWIGRUNTIME int
>> SWIG_Python_ConvertPtrAndOwn(PyObject *obj, void **ptr, swig_type_info
>> *ty, int flags, int *own) {
>>   int res;
>>   SwigPyObject *sobj;
>>   int implicit_conv = (flags & SWIG_POINTER_IMPLICIT_CONV) != 0;
>>
>>   if (!obj){
>>     printf("No obj\n");
>>     return SWIG_ERROR;
>>   }
>>   if (obj == Py_None && !implicit_conv) {
>>     if (ptr)
>>       *ptr = 0;
>>     return SWIG_OK;
>>   }
>>
>>   res = SWIG_ERROR;
>>
>>   sobj = SWIG_Python_GetSwigThis(obj);
>>   if (own)
>>     *own = 0;
>>   while (sobj) {
>>     void *vptr = sobj->ptr;
>>     if (ty) {
>>       swig_type_info *to = sobj->ty;
>>       if (to == ty) {
>>         printf("No type cast needed\n");
>>         /* no type cast needed */
>>         if (ptr) *ptr = vptr;
>>         break;
>>       } else {
>>         printf("Type cast needed\n");
>>         swig_cast_info *tc = SWIG_TypeCheck(to->name,ty);
>>         if (!tc) {
>>           printf("No tc\n");
>>           sobj = (SwigPyObject *)sobj->next;
>>         } else {
>>           printf("Typcast yes\n");
>>           if (ptr) {
>>             printf("If pointer\n");
>>             int newmemory = 0;
>>             *ptr = SWIG_TypeCast(tc,vptr,&newmemory);
>>             if (newmemory == SWIG_CAST_NEW_MEMORY) {
>>               printf("newmemory\n");
>>               assert(own); /* badly formed typemap which will lead to
>> a memory leak - it must set and use own to delete *ptr */
>>               if (own)
>>                 *own = *own | SWIG_CAST_NEW_MEMORY;
>>             }
>>           }
>>           break;
>>         }
>>       }
>>     } else {
>>       printf("pointer\n");
>>       if (ptr) *ptr = vptr;
>>       break;
>>     }
>>   }
>>   if (sobj) {
>>     if (own)
>>       *own = *own | sobj->own;
>>     if (flags & SWIG_POINTER_DISOWN) {
>>       sobj->own = 0;
>>     }
>>     printf("sobj\n");
>>     res = SWIG_OK;
>>   } else {
>>     if (implicit_conv) {
>>       printf("implicit_conv\n");
>>       SwigPyClientData *data = ty ? (SwigPyClientData *) ty->clientdata : 0;
>>       if (data && !data->implicitconv) {
>>         printf("data && !data->implicitconv\n");
>>         PyObject *klass = data->klass;
>>         if (klass) {
>>           printf("klass\n");
>>           PyObject *impconv;
>>           data->implicitconv = 1; /* avoid recursion and call
>> 'explicit' constructors*/
>>           impconv = SWIG_Python_CallFunctor(klass, obj);
>>           data->implicitconv = 0;
>>           if (PyErr_Occurred()) {
>>             printf("PyErr_Occurred()\n");
>>             PyErr_Clear();
>>             impconv = 0;
>>           }
>>           if (impconv) {
>>             printf("impconv\n");
>>             SwigPyObject *iobj = SWIG_Python_GetSwigThis(impconv);
>>             if (iobj) {
>>               printf("iobj\n");
>>               void *vptr;
>>               res = SWIG_Python_ConvertPtrAndOwn((PyObject*)iobj,
>> &vptr, ty, 0, 0);
>>               if (SWIG_IsOK(res)) {
>>                 printf("SWIG_IsOK(res)\n");
>>                 if (ptr) {
>>                   printf("ptr\n");
>>                   *ptr = vptr;
>>                   /* transfer the ownership to 'ptr' */
>>                   iobj->own = 0;
>>                   res = SWIG_AddCast(res);
>>                   res = SWIG_AddNewMask(res);
>>                 } else {
>>                   printf("else ptr\n");
>>                   res = SWIG_AddCast(res);
>>                 }
>>               }
>>             }
>>             Py_DECREF(impconv);
>>           }
>>         }
>>       }
>>     }
>>     if (!SWIG_IsOK(res) && obj == Py_None) {
>>       printf("!SWIG_IsOK(res) && obj == Py_None\n");
>>       if (ptr)
>>         *ptr = 0;
>>       if (PyErr_Occurred())
>>         PyErr_Clear();
>>       res = SWIG_OK;
>>     }
>>   }
>>   return res;
>> }
>> ```
>>
>> I hope someone can help with something... Just in case, you have code
>> available in github:
>> https://github.com/fonlabs/ajtcl/blob/33bd4ba03556c5afafb447cdc4667e4f3faaf782/swig/alljoyn.i
>>
>> Cheers,
>>
>> Javier Domingo Cansino
>> Research & Development Junior Engineer
>> Fon Labs Workgroup, Getxo - Spain.