MDEV-33582 Add more warnings to be able to better diagnose network issues

Warnings are added to net_server.cc when
global_system_variables.log_warnings >= 4.

When the above condition holds then:
- All communication errors from net_serv.cc is also written to the
  error log.
- In case of a of not being able to read or write a packet, a more
  detailed error is given.

Other things:
- Added detection of slaves that has hangup to Ack_receiver::run()
- vio_close() is now first marking the socket closed before closing it.
  The reason for this is to ensure that the connection that gets a read
  error can check if the reason was that the socket was closed.
- Add a new state to vio to be able to detect if vio is acive, shutdown or
  closed. This is used to detect if socket is closed by another thread.
- Testing of the new warnings is done in rpl_get_lock.test
- Suppress some of the new warnings in mtr to allow one to run some of
  the tests with -mysqld=--log-warnings=4. All test in the 'rpl' suite
  can now be run with this option.
 - Ensure that global.log_warnings are restored at test end in a way
   that allows one to use mtr --mysqld=--log-warnings=4.

Reviewed-by: <serg@mariadb.org>,<brandon.nesterenko@mariadb.com>

Author: montywi

include/my_global.h

@@ -962,6 +962,7 @@ typedef struct st_mysql_lex_string LEX_STRING;
 #define SOCKET_ECONNRESET WSAECONNRESET
 #define SOCKET_ENFILE	ENFILE
 #define SOCKET_EMFILE	EMFILE
+#define SOCKET_CLOSED   EIO
 #else /* Unix */
 #define socket_errno	errno
 #define closesocket(A)	close(A)
@@ -971,6 +972,7 @@ typedef struct st_mysql_lex_string LEX_STRING;
 #define SOCKET_EADDRINUSE EADDRINUSE
 #define SOCKET_ETIMEDOUT ETIMEDOUT
 #define SOCKET_ECONNRESET ECONNRESET
+#define SOCKET_CLOSED   EIO
 #define SOCKET_ENFILE	ENFILE
 #define SOCKET_EMFILE	EMFILE
 #endif

include/violite.h

@@ -41,6 +41,13 @@ enum enum_vio_type
   VIO_TYPE_SSL
   /* see also vio_type_names[] */
 };
+
+enum enum_vio_state
+{
+  VIO_STATE_NOT_INITIALIZED, VIO_STATE_ACTIVE, VIO_STATE_SHUTDOWN,
+  VIO_STATE_CLOSED
+};
+
 #define FIRST_VIO_TYPE VIO_CLOSED
 #define LAST_VIO_TYPE VIO_TYPE_SSL
 
@@ -244,6 +251,7 @@ struct st_vio
   struct sockaddr_storage local;	/* Local internet address */
   struct sockaddr_storage remote;	/* Remote internet address */
   enum enum_vio_type	type;		/* Type of connection */
+  enum enum_vio_state	state;		/* State of the connection */
   const char		*desc;		/* String description */
   char                  *read_buffer;   /* buffer for vio_read_buff */
   char                  *read_pos;      /* start of unfetched data in the

mysql-test/mariadb-test-run.pl

@@ -4486,6 +4486,13 @@ ($$)
      qr/Slave I\/0: Master command COM_BINLOG_DUMP failed/,
      qr/Error reading packet/,
      qr/Lost connection to MariaDB server at 'reading initial communication packet'/,
+     qr/Could not read packet:.* state: [2-3] /,
+     qr/Could not read packet:.* errno: 104 /,
+     qr/Could not read packet:.* errno: 0 .* length: 0/,
+     qr/Could not write packet:.* errno: 32 /,
+     qr/Could not write packet:.* errno: 104 /,
+     qr/Semisync ack receiver got error 1158/,
+     qr/Connection was killed/,
      qr/Failed on request_dump/,
      qr/Slave: Can't drop database.* database doesn't exist/,
      qr/Slave: Operation DROP USER failed for 'create_rout_db'/,

mysql-test/suite/binlog_encryption/rpl_packet.result

@@ -2,6 +2,8 @@ include/master-slave.inc
 [connection master]
 call mtr.add_suppression("Slave I/O: Got a packet bigger than 'slave_max_allowed_packet' bytes, .*error.* 1153");
 call mtr.add_suppression("Log entry on master is longer than slave_max_allowed_packet");
+call mtr.add_suppression("Could not write packet:");
+call mtr.add_suppression("Got a packet bigger than 'max_allowed_packet' bytes");
 drop database if exists DB_NAME_OF_MAX_LENGTH_AKA_NAME_LEN_64_BYTES_____________________;
 create database DB_NAME_OF_MAX_LENGTH_AKA_NAME_LEN_64_BYTES_____________________;
 connection master;

mysql-test/suite/rpl/include/rpl_extra_col_master.test

@@ -59,6 +59,10 @@
 #VARCHAR(M)    
 #
 
+--disable_query_log
+call mtr.add_suppression("Could not read packet:.* errno: 11");
+--enable_query_log
+
 --let $_saved_conn= $CURRENT_CONNECTION
 
 let $binformat = `SHOW VARIABLES LIKE '%binlog_format%'`;

mysql-test/suite/rpl/r/rpl_binlog_dump_slave_gtid_state_info.result

@@ -1,6 +1,7 @@
 include/master-slave.inc
 [connection master]
 connection master;
+SET @org_log_warnings=@@GLOBAL.LOG_WARNINGS;
 SET GLOBAL LOG_WARNINGS=2;
 connection slave;
 include/stop_slave.inc
@@ -41,11 +42,11 @@ connection master;
 include/wait_for_pattern_in_file.inc
 FOUND 1 /using_gtid\(1\), gtid\(\'0-1-2,10-1-1\'\).*/ in mysqld.1.err
 "===== Clean up ====="
+SET GLOBAL LOG_WARNINGS=@org_log_warnings;
 connection slave;
 include/stop_slave.inc
 CHANGE MASTER TO MASTER_USE_GTID=no;
 include/start_slave.inc
 connection master;
 DROP TABLE t;
-SET GLOBAL LOG_WARNINGS=default;
 include/rpl_end.inc

mysql-test/suite/rpl/r/rpl_domain_id_filter_master_crash.result

@@ -1,9 +1,6 @@
 include/master-slave.inc
 [connection master]
 connection master;
-call mtr.add_suppression("mysqld: Table '.*gtid_slave_pos' is marked as crashed and should be repaired");
-call mtr.add_suppression("Checking table:   './mysql/gtid_slave_pos'");
-call mtr.add_suppression("mysql.gtid_slave_pos: 1 client is using or hasn't closed the table properly");
 SET @@session.gtid_domain_id= 0;
 create table ti (a int auto_increment primary key) engine=innodb;
 create table tm (a int auto_increment primary key) engine=myisam;

mysql-test/suite/rpl/r/rpl_get_lock.result

@@ -1,6 +1,6 @@
 include/master-slave.inc
 [connection master]
-CALL mtr.add_suppression("Unsafe statement written to the binary log using statement format since BINLOG_FORMAT = STATEMENT");
+SET GLOBAL LOG_WARNINGS=4;
 create table t1(n int);
 insert into t1 values(get_lock("lock",2));
 disconnect master;
@@ -35,4 +35,5 @@ NULL
 connection master1;
 drop table t1;
 connection slave;
+connection default;
 include/rpl_end.inc

mysql-test/suite/rpl/r/rpl_gtid_crash.result

@@ -4,6 +4,7 @@ connection server_1;
 call mtr.add_suppression("Checking table:");
 call mtr.add_suppression("client is using or hasn't closed the table properly");
 call mtr.add_suppression("Table .* is marked as crashed and should be repaired");
+call mtr.add_suppression("Could not read packet:.* errno: 11");
 flush tables;
 ALTER TABLE mysql.gtid_slave_pos ENGINE=InnoDB;
 CREATE TABLE t1 (a INT PRIMARY KEY, b INT) ENGINE=InnoDB;

mysql-test/suite/rpl/r/rpl_gtid_grouping.result

@@ -50,5 +50,4 @@ CHANGE MASTER TO MASTER_USE_GTID=no;
 include/start_slave.inc
 connection master;
 DROP TABLE t;
-SET GLOBAL LOG_WARNINGS=default;
 include/rpl_end.inc