[PATHC] Fix minor memory leak in pg_basebackup

[Zhang, Jie]

Hi all

In some cases , PGresult is not cleared.

File: src\bin\pg_basebackup\streamutil.c

bool
RetrieveWalSegSize(PGconn *conn)
{
        PGresult   *res;
......
        res = PQexec(conn, "SHOW wal_segment_size");
        if (PQresultStatus(res) != PGRES_TUPLES_OK)
        {
                pg_log_error("could not send replication command \"%s\": %s",
                                         "SHOW wal_segment_size", 
PQerrorMessage(conn));

                PQclear(res); // *** res  is cleared  ***
                return false;
        }
......
        /* fetch xlog value and unit from the result */
        if (sscanf(PQgetvalue(res, 0, 0), "%d%s", &xlog_val, xlog_unit) != 2)
        {
                pg_log_error("WAL segment size could not be parsed");
                return false;    // *** res  is not cleared  ***
        }
......
        if (!IsValidWalSegSize(WalSegSz))
        {
                pg_log_error(ngettext("WAL segment size must be a power of two 
between 1 MB and 1 GB, but the remote server reported a value of %d byte",
                                                          "WAL segment size 
must be a power of two between 1 MB and 1 GB, but the remote server reported a 
value of %d bytes",
                                                          WalSegSz),
                                         WalSegSz);
                return false;   ;    // *** res  is not cleared  ***
        }
......


Here is a patch.

Best Regards!

pg_basebackup.patch
Description: pg_basebackup.patch