Bug #30755992: MYSQL DUMP "SUFFICIENTLY LONG" NETWORK TIMEOUT TOO SHORT

RB#23667

Increased the hard-coded network timeout from 700 secs to 86400 (1 day
in seconds).
The rationale is that it has to be big enough. One day is big enough for
everybody. But not infinite.

client/mysqldump.cc

@@ -1,5 +1,5 @@
 /*
-   Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
+   Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License, version 2.0,
@@ -1520,7 +1520,7 @@ static int connect_to_db(char *host, char *user, char *passwd) {
                 &opt_zstd_compress_level);
 
   if (opt_network_timeout) {
-    uint timeout = 700;
+    uint timeout = 86400;  // 1 day in seconds
     ulong max_packet_allowed = 1024L * 1024L * 1024L;
 
     mysql_options(&mysql_connection, MYSQL_OPT_READ_TIMEOUT, (char *)&timeout);
@@ -1597,8 +1597,8 @@ static int connect_to_db(char *host, char *user, char *passwd) {
   */
   if (opt_network_timeout) {
     snprintf(buff, sizeof(buff),
-             "SET SESSION NET_READ_TIMEOUT= 700, "
-             "SESSION NET_WRITE_TIMEOUT= 700 ");
+             "SET SESSION NET_READ_TIMEOUT= 86400, "
+             "SESSION NET_WRITE_TIMEOUT= 86400 ");  // 1 day in seconds
     if (mysql_query_with_error_report(mysql, 0, buff)) return 1;
   }