BUG#16217 forced to introduce a separate mysql client command to adopt its

internal charset to one associated with currently being handled query. 
To note such a query can come from interactive client either.

There was a discussion within replication team and Monty who's suggestion won.
It avoids straightforward parsing of all `set' queries that could affect client side 
character set. 
According to the idea, mysql client does not parse `set' queries but rather cares of
`charset new_cs_name' command.
This command is generated by mysqlbinlog in form of exclaiming comment (Lars' suggestion)
so that enlightened clients like `mysql' knows what to do with it.

Interactive human can switch between many multi-byte charsets during the session 
providing the command explicitly. 
To note that setting new internal mysql's charset does not
trigger sending any `SET' sql statement to the server. 


client/mysql.cc:
  BUG#16217 revealed the problem of switching between charsets in mysql client.
  Such switching is necessary in a case when being scanned query consists of 
  multi-byte chars and internal charset was initialized differently. mysql finds 
  `/' escape and misiterprete it 
  while in fact one could be a part of a multi-byte symbol like the bug page reported. 
  
  This patch extends mysql `charset' command, '\C' shortcut.
mysql-test/r/ctype_ucs_binlog.result:
  comment line generated by mysqlbinlog for processing of logs with multi-byte chars.
mysql-test/r/mysql.result:
  results are altered due to #16217
mysql-test/r/mysqlbinlog.result:
  Results are altered due to #16217
mysql-test/r/mysqlbinlog2.result:
  commeted command for mysql client due to multi-byte binlog
mysql-test/r/rpl_charset.result:
  commented command for mysql due to multi-byte binlogs
mysql-test/r/rpl_timezone.result:
  commented command for mysql client due to multi-byte binlogs
mysql-test/r/user_var-binlog.result:
  commented command for mysql client due to multi-byte binlogs
mysql-test/t/mysql.test:
  Main test for mysql client is extended to check `charset' command.
mysql-test/t/mysqlbinlog.test:
  Checking how /*! \C cs_name */ are added to the output of mysqlbinlog.
  The exclaiming comment is for further processing by mysql client.
  The added part mimics the failure to recover tables from binlog - see BUG#16217.
sql/log_event.cc:
  Sending into output instructions for mysql client to switch internally 
  to appropriate charset.
  mysql client is supposed to be invoked with --default-character-set=
  "to default character set of the server created the binlog".

1 files changed, 13 insertions, 0 deletions

diff --git a/mysql-test/t/mysql.test b/mysql-test/t/mysql.test
index 0783c043ef6..7a9a1ee3f60 100644
--- a/mysql-test/t/mysql.test
+++ b/mysql-test/t/mysql.test
@@ -41,3 +41,16 @@ lock tables t1 write;
 unlock tables;
 drop table t1;
 
+#
+# BUG#16217 - MySQL client misinterpretes multi-byte char as escape `\' 
+#
+
+# new command \C or charset
+--exec $MYSQL --default-character-set=utf8 test -e "\C cp932 \g"
+--exec $MYSQL --default-character-set=cp932 test -e "charset utf8;"
+
+# its usage to switch internally in mysql to requested charset
+--exec $MYSQL --default-character-set=utf8 test -e "charset cp932; set @@session.character_set_client= cp932; select 'ソ'; create table t1 (c_cp932 TEXT CHARACTER SET cp932); insert into t1 values('ソ'); select * from t1;  drop table t1;"
+--exec $MYSQL --default-character-set=utf8 test -e "charset cp932; set character_set_client= cp932; select 'ソ'"
+--exec $MYSQL --default-character-set=utf8 test -e "/*charset cp932 */; set character_set_client= cp932; select 'ソ'"
+--exec $MYSQL --default-character-set=utf8 test -e "/*!\C cp932 */; set character_set_client= cp932; select 'ソ'"