Coverity/static analysis issues with TCP interface code

[jsquyres]

@drwootton @jjhursey Looks like we got some static analysis problems from 0b37cd2 (PR #9681). Can you fix?

Thanks!

________________________________________________________________________________________________________
*** CID 1494436:  Null pointer dereferences  (FORWARD_NULL)
/opal/mca/btl/tcp/btl_tcp_component.c: 758 in split_and_resolve()
752             }
753     
754             free(tmp);
755         }
756     
757         /* Mark the end of the interface name array with NULL */
   CID 1494436:  Null pointer dereferences  (FORWARD_NULL)
   Dereferencing null pointer "interfaces".
758         interfaces[interface_count] = NULL;
759         free(argv);
760         free(*orig_str);
761         *orig_str = opal_argv_join(interfaces, ',');
762         return interfaces;
763     }

** CID 1494435:    (RESOURCE_LEAK)
/opal/mca/btl/tcp/btl_tcp_component.c: 676 in split_and_resolve()
/opal/mca/btl/tcp/btl_tcp_component.c: 738 in split_and_resolve()
________________________________________________________________________________________________________
*** CID 1494435:    (RESOURCE_LEAK)
/opal/mca/btl/tcp/btl_tcp_component.c: 676 in split_and_resolve()
670                     }
671                 }
672                 if (n == interface_count) {
673                     opal_output_verbose(20,
674                                         opal_btl_base_framework.framework_output,
675                                         "btl: tcp: Using interface: %s ", argv[i]);
   CID 1494435:    (RESOURCE_LEAK)
   Failing to save or free storage allocated by "strdup(argv[i])" leaks it.
676                     opal_argv_append(&interface_count, &interfaces, strdup(argv[i]));
677                 }
678                 continue;
679             }
680     
681             /* Found a subnet notation.  Convert it to an IP
/opal/mca/btl/tcp/btl_tcp_component.c: 738 in split_and_resolve()
732                     if (n == interface_count) {
733                         opal_output_verbose(20,
734                                             opal_btl_base_framework.framework_output,
735                                             "btl: tcp: Found match: %s (%s)",
736                                             opal_net_get_hostname((struct sockaddr*) &if_inaddr),
737                                             if_name);
   CID 1494435:    (RESOURCE_LEAK)
   Failing to save or free storage allocated by "strdup(if_name)" leaks it.
738                         opal_argv_append(&interface_count, &interfaces, strdup(if_name));
739                     }
740                 }
741             }
742     
743             /* If we didn't find a match, keep trying */

[drwootton]

I started looking at this. I need to discuss with @jjhursey to figure out how to deal with the resource leak complaints.

[jsquyres]

Thanks @drwootton!

[bosilca]

opal_argv_append already strdup the appended string, so you don't have to explicitly call strdup. The solution is to just remove the strdup from the opal_argv_append calls.

[drwootton]

I didn't realize the strdup was taken care of already. I also know what I need to do to take care of the potential null pointer dereference, so I'll take care of this all on Monday.

Thanks.

[jjhursey]

PR #9705 should resolve the coverity issues. We will watch the coverity report now that this is merged into master.