MDEV-16865 InnoDB fts_query() ignores KILL

The functions fts_ast_visit() and fts_query() inside
InnoDB FULLTEXT INDEX query processing are not checking
for THD::killed (trx_is_interrupted()), like anything
that potentially takes a long time should do.

This is a port of the following change from MySQL 5.7.23,
with a completely rewritten test case.

commit c58c6f8f66ddd0357ecd0c99646aa6bf1dae49c8
Author: Aakanksha Verma <aakanksha.verma@oracle.com>
Date:   Fri May 4 15:53:13 2018 +0530

Bug #27155294 MAX_EXECUTION_TIME NOT INTERUPTED WITH FULLTEXT SEARCH USING MECAB

2 files changed, 36 insertions, 0 deletions

diff --git a/mysql-test/suite/innodb_fts/r/fts_kill_query.result b/mysql-test/suite/innodb_fts/r/fts_kill_query.result
new file mode 100644
index 00000000000..45623f96ab0
--- /dev/null
+++ b/mysql-test/suite/innodb_fts/r/fts_kill_query.result
@@ -0,0 +1,6 @@
+CREATE TABLE t1 (a VARCHAR(7), b text, FULLTEXT KEY idx (a,b)) ENGINE=InnoDB;
+COMMIT;
+SELECT COUNT(*) FROM t1
+WHERE MATCH (a,b) AGAINST ('foo bar' IN BOOLEAN MODE);
+KILL QUERY @id;
+DROP TABLE t1;
diff --git a/mysql-test/suite/innodb_fts/t/fts_kill_query.test b/mysql-test/suite/innodb_fts/t/fts_kill_query.test
new file mode 100644
index 00000000000..3dda29a3876
--- /dev/null
+++ b/mysql-test/suite/innodb_fts/t/fts_kill_query.test
@@ -0,0 +1,30 @@
+--source include/have_innodb.inc
+
+CREATE TABLE t1 (a VARCHAR(7), b text, FULLTEXT KEY idx (a,b)) ENGINE=InnoDB;
+
+--disable_query_log
+BEGIN;
+let $n=1000;
+while ($n) {
+INSERT INTO t1 VALUES('foo bar','boo far');
+dec $n;
+}
+--enable_query_log
+COMMIT;
+
+let $id = `SELECT CONNECTION_ID()`;
+send SELECT COUNT(*) FROM t1
+WHERE MATCH (a,b) AGAINST ('foo bar' IN BOOLEAN MODE);
+
+connect (con1,localhost,root,,);
+let $ignore= `SELECT @id := $ID`;
+KILL QUERY @id;
+disconnect con1;
+
+connection default;
+# The following would return a result set if the KILL was not fast enough.
+--disable_result_log
+--error 0,ER_QUERY_INTERRUPTED,HA_ERR_ABORTED_BY_USER
+reap;
+--enable_result_log
+DROP TABLE t1;