BUG #15838: [contrib] vacuumlo: schema variable checked for NULL three times

On 07/06/2019 09:15, PG Bug reporting form wrote:

 vacuumlo() has this (starting on line 239):

                  if (!schema || !table || !field)
                  {
                          fprintf(stderr, "%s", PQerrorMessage(conn));
                          PQclear(res);
                          PQfinish(conn);
                          if (schema != NULL)
                                  PQfreemem(schema);
                          if (schema != NULL)
                                  PQfreemem(table);
                          if (schema != NULL)
                                  PQfreemem(field);
                          return -1;
                  }

 I think this can be replaced with this:

                  if (!schema || !table || !field)
                  {
                          fprintf(stderr, "%s", PQerrorMessage(conn));
                          PQclear(res);
                          PQfinish(conn);
                          if (schema != NULL) {
                                  PQfreemem(schema);
                                  PQfreemem(table);
                                  PQfreemem(field);
                          }
                          return -1;
                  }

Hmm. Currently, if allocating 'schema' fails, but allocating 'table' or
'field' succeeds, you leak memory. I'm pretty sure that was intended to be:

         if (!schema || !table || !field)
         {
             fprintf(stderr, "%s", PQerrorMessage(conn));
             PQclear(res);
             PQfinish(conn);
             if (schema != NULL)
                 PQfreemem(schema);
             if (table != NULL)
                 PQfreemem(table);
             if (field != NULL)
                 PQfreemem(field);
             return -1;
         }

I'll go fix it that way, thanks for the report!

- Heikki