Re: [libodbcxx-devel] segmentation fault help please

[Pete <pe...@ka...>]

Further to Jan's suggestions, unless you do:

odbc::DriverManager::shutdown();
 
before exiting from your program you'll get leaks.

Pete

> -----Original Message-----
> From: Simon Walter [mailto:si...@gi...] 
> Sent: Wednesday, 6 June 2012 5:45 p.m.
> To: lib...@li...
> Subject: [libodbcxx-devel] segmentation fault help please
> 
> Hi,
> 
> I have here a very simple test program that crashes with a 
> SIGSEGV. When running it through valgrind, it shows memory leaks.
> 
> I've written this piece of code as I am having trouble with a 
> larger project. However, I think I've isolated it to 
> libodbc++ or unixodbc.
> 
> I initially used std::unique_ptr. But thought I'd try plain 
> old pointers for this test. Either way, there are probelms.
> 
> Here is the program:
> ---------------------------------------
> #include <string>
> #include <sstream>
> #include <iostream>
> #include <odbc++/drivermanager.h>
> #include <odbc++/connection.h>
> #include <odbc++/preparedstatement.h>
> #include <odbc++/callablestatement.h>
> #include <odbc++/resultset.h>
> #include <odbc++/databasemetadata.h>
> #include <odbc++/resultsetmetadata.h>
> 
> 
> int main(int argc, char** argv)
> {
>      int test;
>      std::string dbConnectString = 
> "DSN=agentportal;USER=xxx;PASSWORD=xxx";
>      std::stringstream query;
>      query << "select sleep(" << 30 << "), 1 as test";
> 
>      try
>      {
>          odbc::Connection* connection = 
> odbc::DriverManager::getConnection(dbConnectString);
>          odbc::Statement* statement = connection->createStatement();
>          odbc::ResultSet* resultSet = 
> statement->executeQuery(query.str());
> 
>          while (resultSet->next())
>          {
>              test = resultSet->getInt("test");
>          }
> 
>          delete connection;
>          delete statement;
>          delete resultSet;
>      }
>      catch(odbc::SQLException& e)
>      {
>          std::cout << std::endl << "error code: "<< 
> e.getErrorCode() << std::endl << "error message: " << 
> e.getMessage() << std::endl;
>      }
> 
>      return 0;
> }
> ---------------------------------------
> #include <string>
> #include <sstream>
> #include <iostream>
> #include <memory>
> #include <odbc++/drivermanager.h>
> #include <odbc++/connection.h>
> #include <odbc++/preparedstatement.h>
> #include <odbc++/callablestatement.h>
> #include <odbc++/resultset.h>
> #include <odbc++/databasemetadata.h>
> #include <odbc++/resultsetmetadata.h>
> 
> 
> int main(int argc, char** argv)
> {
>      int test;
>      std::string dbConnectString = 
> "DSN=agentportal;USER=xxx;PASSWORD=xxx";
>      std::stringstream query;
>      query << "select 1 as test";
> 
>      try
>      {
>          std::unique_ptr<odbc::Connection> connection 
> (odbc::DriverManager::getConnection(dbConnectString));
>          std::unique_ptr<odbc::Statement> statement 
> (connection->createStatement());
>          std::unique_ptr<odbc::ResultSet> resultSet 
> (statement->executeQuery(query.str()));
> 
>          while (resultSet->next())
>          {
>              test = resultSet->getInt("test");
>          }
>          std::cout << test << std::endl;
>      }
>      catch(odbc::SQLException& e)
>      {
>          std::cout << std::endl << "error code: "<< 
> e.getErrorCode() << std::endl << "error message: " << 
> e.getMessage() << std::endl;
>      }
> 
>      return 0;
> }
> ---------------------------------------
> (gdb) r
> Starting program: /home/weelz/htserve/trunk/testODBC
> [Thread debugging using libthread_db enabled] [New Thread 
> 0xb799cb70 (LWP 7865)] [Thread 0xb799cb70 (LWP 7865) exited]
> 
> Program received signal SIGSEGV, Segmentation fault.
> 0x00000489 in ?? ()
> (gdb) bt
> #0  0x00000489 in ?? ()
> #1  0xb7d18ca6 in __libc_start_main (main=0x8048e64 <main>, 
> argc=1, ubp_av=0xbffff7a4, init=0x8049230 <__libc_csu_init>, 
> fini=0x8049220 <__libc_csu_fini>, rtld_fini=0xb7ff1380 
> <_dl_fini>, stack_end=0xbffff79c)
>      at libc-start.c:228
> #2  0x08048dd1 in _start ()
> (gdb)
> ---------------------------------------
> I've attached the valgrind output as it is rather long. 
> prt.log is for the plain pointer version up top. unique.log 
> is for the version that uses unique_ptr. Admittedly, the 
> unique_ptr behaves better, but still has issues.
> 
> I suspect I am doing something wrong when compiling libodbc++ 
> rather than there is a bug. I see the similar behavior with 
> TDS as well.
> 
> Short of building everything from source (gentoo?), I thought 
> I'd see if anyone has any ideas on what could be the problem.
> 
> Has anyone run into similar issues?
> 
> Thanks,
> 
> Simon
> 
> --
> simonsmicrophone.com
>