Bug#19371 VARBINARY() have trailing zeros after upgrade from 4.1

 - Detect if a table has field of type MYSQL_TYPE_VAR_STRING while running
   "CHECK TABLE t FOR UPGRADE" and indicate it need to be fixed
   with "REPAIR TABLE t".
 - When running a "REPAIR TABLE t" or "ALTER TABLE t FORCE" on the above
   table, install a special copy function to trim off the trailing spaces
   which we safely can say that the pre 5.0 mysqld didn't put there. 


mysql-test/r/varbinary.result:
  Add test to see that a table with varbinary from 4.1 can be REPAIRED
mysql-test/t/varbinary.test:
  Add test to see that a table with varbinary from 4.1 can be REPAIRED
sql/field_conv.cc:
  Add new field copy function 'do_field_varbinary_pre50' used for copying
  between MYSQL_TYPE_VAR_STRING and MYSQL_TYPE_VARCHAR. It will remove trailing
  spaces from the field as MySQL <= 4.1 never stores the trailing spaces for
  a MYSQL_TYPE_VAR_STRING.
  Install this new copy function in ALTER TABLEs list of functions to use for
  copying data during and alter if from field is a <= 4.1 varbinary and to
  field is 5.0 varbinary.
sql/handler.cc:
  If the table has a pre 5.0 varbinary, table not to be altered so the field
  type is upgraded to 5.0 version and trailing space can be trimmed.
mysql-test/std_data/bug19371.MYD:
  New BitKeeper file ``mysql-test/std_data/bug19371.MYD''
mysql-test/std_data/bug19371.MYI:
  New BitKeeper file ``mysql-test/std_data/bug19371.MYI''
mysql-test/std_data/bug19371.frm:
  New BitKeeper file ``mysql-test/std_data/bug19371.frm''

1 files changed, 40 insertions, 0 deletions

diff --git a/mysql-test/t/varbinary.test b/mysql-test/t/varbinary.test
index 5fbd116d7b8..a20359ac00e 100644
--- a/mysql-test/t/varbinary.test
+++ b/mysql-test/t/varbinary.test
@@ -37,3 +37,43 @@ select x,xx from t1;
 drop table t1;
 
 # End of 4.1 tests
+
+#
+# Bug #19371 VARBINARY() have trailing zeros after upgrade from 4.1
+#
+
+# Test with a saved table from 4.1
+copy_file std_data/bug19371.frm $MYSQLTEST_VARDIR/master-data/test/t1.frm;
+copy_file std_data/bug19371.MYD $MYSQLTEST_VARDIR/master-data/test/t1.MYD;
+copy_file std_data/bug19371.MYI $MYSQLTEST_VARDIR/master-data/test/t1.MYI;
+
+# Everything _looks_ fine
+show create table t1;
+
+# But the length of the varbinary columns are too long
+select length(a), length(b) from t1;
+
+# Run CHECK TABLE, it should indicate table need a REPAIR TABLE
+CHECK TABLE t1 FOR UPGRADE;
+
+# Run REPAIR TABLE to alter the table and repair
+# the varbinary fields
+REPAIR TABLE t1;
+
+# Now check it's back to normal
+show create table t1;
+select length(a), length(b) from t1;
+insert into t1 values("ccc", "ddd");
+select length(a), length(b) from t1;
+select hex(a), hex(b) from t1;
+select concat("'", a, "'"), concat("'", b, "'") from t1;
+
+drop table t1;
+
+# Check that the fix does not affect table created with current version
+create table t1(a varbinary(255));
+insert into t1 values("aaa   ");
+select length(a) from t1;
+alter table t1 modify a varchar(255);
+select length(a) from t1;
+