BUG#11764339 - valgrind errors, random data when returning

               ordered data from archive tables

Archive was using wrong memory address to check if field
is NULL (after filesort, when reading record again).

mysql-test/r/archive.result:
  A test case for BUG#11764339.
mysql-test/t/archive.test:
  A test case for BUG#11764339.
storage/archive/ha_archive.cc:
  Null bytes are restored to "record" buffer, which may
  or may not be equal to record buffer for field. Check
  null bits in "record" buffer, instead of Field::null_ptr.

mysql-test/r/archive.result

@@ -12756,3 +12756,19 @@ a
 1
 2
 DROP TABLE t1;
+#
+# BUG#57162 - valgrind errors, random data when returning
+#             ordered data from archive tables
+#
+SET sort_buffer_size=32804;
+CREATE TABLE t1(a INT, b CHAR(255), c CHAR(255), d CHAR(255),
+e CHAR(255), f INT) ENGINE=ARCHIVE DEFAULT CHARSET utf8;
+INSERT INTO t1 VALUES(-1,'b','c','d','e',1);
+INSERT INTO t1 SELECT * FROM t1;
+INSERT INTO t1 SELECT * FROM t1;
+INSERT INTO t1 SELECT t1.* FROM t1,t1 t2,t1 t3,t1 t4,t1 t5,t1 t6;
+SELECT * FROM t1 ORDER BY f LIMIT 1;
+a	b	c	d	e	f
+-1	b	c	d	e	1
+DROP TABLE t1;
+SET sort_buffer_size=DEFAULT;

mysql-test/t/archive.test

@@ -1678,3 +1678,18 @@ SELECT * FROM t1;
 REPAIR TABLE t1 EXTENDED;
 SELECT * FROM t1;
 DROP TABLE t1;
+
+--echo #
+--echo # BUG#57162 - valgrind errors, random data when returning
+--echo #             ordered data from archive tables
+--echo #
+SET sort_buffer_size=32804;
+CREATE TABLE t1(a INT, b CHAR(255), c CHAR(255), d CHAR(255),
+  e CHAR(255), f INT) ENGINE=ARCHIVE DEFAULT CHARSET utf8;
+INSERT INTO t1 VALUES(-1,'b','c','d','e',1);
+INSERT INTO t1 SELECT * FROM t1;
+INSERT INTO t1 SELECT * FROM t1;
+INSERT INTO t1 SELECT t1.* FROM t1,t1 t2,t1 t3,t1 t4,t1 t5,t1 t6;
+SELECT * FROM t1 ORDER BY f LIMIT 1;
+DROP TABLE t1;
+SET sort_buffer_size=DEFAULT;

storage/archive/ha_archive.cc

@@ -1111,7 +1111,7 @@ int ha_archive::unpack_row(azio_stream *file_to_read, uchar *record)
   ptr+= table->s->null_bytes;
   for (Field **field=table->field ; *field ; field++)
   {
-    if (!((*field)->is_null()))
+    if (!((*field)->is_null_in_record(record)))
     {
       ptr= (*field)->unpack(record + (*field)->offset(table->record[0]), ptr);
     }