Re: SQLPutData bug ? - Mailing list pgsql-bugs

Hiroshi Inoue wrote:

> Mika Mantyla wrote:
>
>>Your name               : Mika Ma"ntyla"
>>
>
>>Your email address      : mmantyla@soberit.hut.fi
>>
>>System Configuration
>>---------------------
>>   Architecture (example: Intel Pentium)         : AMD Athlon
>>
>>   Operating System (example: Linux 2.0.26 ELF)  : RH 7.1
>>
>>   PostgreSQL version (example: PostgreSQL-7.1.3): PostgreSQL-7.1.3
>>
>>   Compiler used (example:  gcc 2.95.2)          : gcc-2.96-97.1 (Used
>>pre-build binaries)
>>
>>FULL description of your problem:
>>------------------------------------------------
>>We have ODBC application that is currently running on top of commercial
>>Solid and Sybase databases.With some fixes I got this application to
>>also work on PSQL on top of W2K. Now I'm trying to get the app to work
>>in Linux with libiodbc-3.0.5-1 and postgresql-odbc-7.1.3
>>
>>However there seems to be problem with SQLPutData call. This was already
>>a problem in W2k with PSQL (ODBC 07_01_0006), and you can see the ugly
>>fix I made in the code. In Linux the same fix causes the program to get
>>segmentation fault in st.ParamData call. If I remove the fix the final
>>st.PutData call in the loop fails.
>>
>>I think this could be problem related to odbc somehow, but I really
>>don't know.
>>
>>-------------------------------------------------------
>>/**** Code with the problem **************************
>>     else
>>     {
>>         char buf[256];
>>         int got;
>>         pos = 0;
>>         do
>>         {
>>            // This copies data to buffer buf nothing more
>>             got = data->GetData( pos, buf, sizeof(buf) );
>>
>>#ifdef PSQL
>>#ifdef WIN32
>>            if (got == 0)
>>              break;
>>#endif //WIN32
>>#endif //PSQL
>>
>
> I don't think it's preferable to call SQLPutData with length 0
> for any dbms. Why is the #ifdef needed ?


If I remove the #ifdef, I sometimes get segmentation fault from
st.ParamData(&pos) which calls SQLParamData.

This segmentation fault from SQLParamData only comes with large values
of variable pos e.g 358228.

So it actually could be a problem with the SQLParamData and large values.





>
>
>>            st.PutData( buf, got );
>>             pos += got;
>>         } while( got > 0 );
>>     }
>>     rc = st.ParamData( &pos );
>>
>>-----------------------------------------------------
>>/**** PutData call ************************/
>>void
>>DBStmt::PutData( void *buf, int bufsize )
>>{
>>     t_usec = 0;
>>     do
>>     {
>>         rc = SQLPutData( hstmt, buf, bufsize );
>>     } while( rc==SQL_STILL_EXECUTING && SocketOK() );
>>
>>     if( rc!=SQL_SUCCESS )
>>         throw SQLExc( "SQLPutData failed", rc, hdbc, hstmt );
>>}
>>-----------------------------------------------------
>>/**** ParamData call ************************/
>>int
>>DBStmt::ParamData( long *val )
>>{
>>     t_usec = 0;
>>     do
>>     {
>>         rc = SQLParamData( hstmt, (void**)&val );
>>
>
>                                      Why &val not val ?


Pointer to pointer. Tried chaning that, and it really broke to hole
application down.




--
Mika Ma"ntyla" || SoberIT
09-451 6001  || Spektri Kvartti 3330a