Backport of Bug#36649 to mysql-next-mr

------------------------------------------------------------
revno: 2630.39.3
revision-id: davi.arnaut@sun.com-20081210215359-i876m4zgc2d6rzs3
parent: kostja@sun.com-20081208222938-9es7wl61moli71ht
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 36649-6.0
timestamp: Wed 2008-12-10 19:53:59 -0200
message:
  Bug#36649: Condition area is not properly cleaned up after stored routine invocation

  The problem is that the diagnostics area of a trigger is not
  isolated from the area of the statement that caused the trigger
  invocation. In MySQL terms, it means that warnings generated
  during the execution of the trigger are not removed from the
  "warning area" at the end of the execution.

  Before this fix, the rules for MySQL message list life cycle (see
  manual entry for SHOW WARNINGS) did not apply to statements
  inside stored programs:

    - The manual says that the list of messages is cleared by a
      statement that uses a table (any table). However, such
      statement, if run inside a stored program did not clear the
      message list.
    - The manual says that the list is cleared by a statement that
      generates a new error or a warning, but this was not the case
      with stored program statements either and is changed to be the
      case as well.

  In other words, after this fix, a statement has the same effect
  on the message list regardless of whether it's executed inside a
  stored program/sub-statement or not.

  This introduces an incompatible change:

    - before this fix, a, e.g. statement inside a trigger could
      never clear the global warning list
    - after this fix, a trigger that generates a warning or uses a
      table, clears the global warning list
    - however, when we leave a trigger or a function, the caller's
      warning information is restored (see more on this below).

  This change is not backward compatible as it is intended to make
  MySQL behavior similar to the SQL standard behavior:

  A stored function or trigger will get its own "warning area" (or,
  in standard terminology, diagnostics area).  At the beginning of
  the stored function or trigger, all messages from the caller area
  will be copied to the area of the trigger.  During execution, the
  message list will be cleared according to the MySQL rules
  described on the manual (SHOW WARNINGS entry).  At the end of the
  function/trigger, the "warning area" will be destroyed along with
  all warnings it contains, except that if the last statement of
  the function/trigger generated messages, these are copied into
  the "warning area" of the caller.

  Consequently, statements that use a table or generate a warning
  *will* clear warnings inside the trigger, but that will have no
  effect to the warning list of the calling (outer) statement.

mysql-test/r/sp.result

@@ -6941,6 +6941,101 @@ SELECT * FROM t1 WHERE a = f1();
 ERROR 42S02: Table 'test.t_non_existing' doesn't exist
 DROP FUNCTION f1;
 DROP TABLE t1;
+DROP PROCEDURE IF EXISTS p1;
+CREATE PROCEDURE p1(a INT, b CHAR)
+BEGIN
+IF a > 0 THEN
+CALL p1(a-1, 'ab');
+ELSE
+SELECT 1;
+END IF;
+END|
+SET @save_max_sp_recursion= @@max_sp_recursion_depth;
+SET @@max_sp_recursion_depth= 5;
+CALL p1(4, 'a');
+1
+1
+Warnings:
+Warning	1265	Data truncated for column 'b' at row 1
+Warning	1265	Data truncated for column 'b' at row 1
+Warning	1265	Data truncated for column 'b' at row 1
+Warning	1265	Data truncated for column 'b' at row 1
+SET @@max_sp_recursion_depth= @save_max_sp_recursion;
+DROP PROCEDURE p1;
+DROP PROCEDURE IF EXISTS p1;
+CREATE PROCEDURE p1(a CHAR)
+BEGIN
+SELECT 1;
+SELECT CAST('10 ' as UNSIGNED INTEGER);
+SELECT 1;
+END|
+CALL p1('data truncated parameter');
+1
+1
+CAST('10 ' as UNSIGNED INTEGER)
+10
+1
+1
+Warnings:
+Warning	1265	Data truncated for column 'a' at row 1
+Warning	1292	Truncated incorrect INTEGER value: '10 '
+DROP PROCEDURE p1;
+DROP PROCEDURE IF EXISTS p1;
+DROP PROCEDURE IF EXISTS p2;
+DROP PROCEDURE IF EXISTS p3;
+DROP PROCEDURE IF EXISTS p4;
+CREATE PROCEDURE p1()
+CALL p2()|
+CREATE PROCEDURE p2()
+CALL p3()|
+CREATE PROCEDURE p3()
+CALL p4()|
+CREATE PROCEDURE p4()
+BEGIN
+SELECT 1;
+SELECT CAST('10 ' as UNSIGNED INTEGER);
+SELECT 2;
+END|
+CALL p1();
+1
+1
+CAST('10 ' as UNSIGNED INTEGER)
+10
+2
+2
+Warnings:
+Warning	1292	Truncated incorrect INTEGER value: '10 '
+DROP PROCEDURE p1;
+DROP PROCEDURE p2;
+DROP PROCEDURE p3;
+DROP PROCEDURE p4;
+DROP FUNCTION IF EXISTS f1;
+DROP FUNCTION IF EXISTS f2;
+DROP FUNCTION IF EXISTS f3;
+DROP FUNCTION IF EXISTS f4;
+DROP TABLE IF EXISTS t1;
+CREATE TABLE t1 (a CHAR(2));
+INSERT INTO t1 VALUES ('aa');
+CREATE FUNCTION f1() RETURNS CHAR
+RETURN (SELECT f2())|
+CREATE FUNCTION f2() RETURNS CHAR
+RETURN (SELECT f3())|
+CREATE FUNCTION f3() RETURNS CHAR
+RETURN (SELECT f4())|
+CREATE FUNCTION f4() RETURNS CHAR
+BEGIN
+RETURN (SELECT a FROM t1);
+END|
+SELECT f1();
+f1()
+a
+Warnings:
+Warning	1265	Data truncated for column 'f4()' at row 1
+DROP FUNCTION f1;
+DROP FUNCTION f2;
+DROP FUNCTION f3;
+DROP FUNCTION f4;
+DROP TABLE t1;
 #
 # Bug#34197: CREATE PROCEDURE fails when COMMENT truncated in non 
 #            strict SQL mode

mysql-test/r/trigger.result

@@ -2115,3 +2115,50 @@ s1
 DELETE FROM t1;
 DROP TABLE t1;
 DROP TEMPORARY TABLE t2;
+DROP TRIGGER IF EXISTS trg1;
+DROP TABLE IF EXISTS t1;
+CREATE TABLE t1 (a INT);
+CREATE TRIGGER trg1 BEFORE INSERT ON t1 FOR EACH ROW
+BEGIN
+DECLARE a CHAR;
+SELECT 'ab' INTO a;
+SELECT 'ab' INTO a;
+SELECT 'a' INTO a;
+END|
+INSERT INTO t1 VALUES (1);
+Warnings:
+Warning	1265	Data truncated for column 'a' at row 1
+DROP TRIGGER trg1;
+DROP TABLE t1;
+DROP TRIGGER IF EXISTS trg1;
+DROP TRIGGER IF EXISTS trg2;
+DROP TABLE IF EXISTS t1;
+CREATE TABLE t1 (a INT);
+CREATE TRIGGER trg1 BEFORE INSERT ON t1 FOR EACH ROW
+BEGIN
+DECLARE trg1 CHAR;
+SELECT 'ab' INTO trg1;
+END|
+CREATE TRIGGER trg2 AFTER INSERT ON t1 FOR EACH ROW
+BEGIN
+DECLARE trg2 CHAR;
+SELECT 'ab' INTO trg2;
+END|
+INSERT INTO t1 VALUES (0);
+Warnings:
+Warning	1265	Data truncated for column 'trg1' at row 1
+Warning	1265	Data truncated for column 'trg2' at row 1
+SELECT * FROM t1;
+a
+0
+SHOW WARNINGS;
+Level	Code	Message
+INSERT INTO t1 VALUES (1),(2);
+Warnings:
+Warning	1265	Data truncated for column 'trg1' at row 1
+Warning	1265	Data truncated for column 'trg2' at row 1
+Warning	1265	Data truncated for column 'trg1' at row 1
+Warning	1265	Data truncated for column 'trg2' at row 1
+DROP TRIGGER trg1;
+DROP TRIGGER trg2;
+DROP TABLE t1;

mysql-test/t/sp.test

@@ -8295,6 +8295,119 @@ SELECT * FROM t1 WHERE a = f1();
 DROP FUNCTION f1;
 DROP TABLE t1;
 
+#
+# Bug#36649: Condition area is not properly cleaned up after stored routine invocation
+#
+
+--disable_warnings
+DROP PROCEDURE IF EXISTS p1;
+--enable_warnings
+
+delimiter |;
+CREATE PROCEDURE p1(a INT, b CHAR)
+BEGIN
+  IF a > 0 THEN
+    CALL p1(a-1, 'ab');
+  ELSE
+    SELECT 1;
+  END IF;
+END|
+delimiter ;|
+
+SET @save_max_sp_recursion= @@max_sp_recursion_depth;
+SET @@max_sp_recursion_depth= 5;
+CALL p1(4, 'a');
+SET @@max_sp_recursion_depth= @save_max_sp_recursion;
+
+DROP PROCEDURE p1;
+
+#
+# Ensure that rules for message list clean up are being respected.
+#
+
+--disable_warnings
+DROP PROCEDURE IF EXISTS p1;
+--enable_warnings
+
+delimiter |;
+CREATE PROCEDURE p1(a CHAR)
+BEGIN
+  SELECT 1;
+  SELECT CAST('10 ' as UNSIGNED INTEGER);
+  SELECT 1;
+END|
+delimiter ;|
+
+CALL p1('data truncated parameter');
+
+DROP PROCEDURE p1;
+
+#
+# Cascading stored procedure/function calls.
+#
+
+--disable_warnings
+DROP PROCEDURE IF EXISTS p1;
+DROP PROCEDURE IF EXISTS p2;
+DROP PROCEDURE IF EXISTS p3;
+DROP PROCEDURE IF EXISTS p4;
+--enable_warnings
+
+delimiter |;
+CREATE PROCEDURE p1()
+  CALL p2()|
+CREATE PROCEDURE p2()
+  CALL p3()|
+CREATE PROCEDURE p3()
+  CALL p4()|
+CREATE PROCEDURE p4()
+BEGIN
+  SELECT 1;
+  SELECT CAST('10 ' as UNSIGNED INTEGER);
+  SELECT 2;
+END|
+delimiter ;|
+
+CALL p1();
+
+DROP PROCEDURE p1;
+DROP PROCEDURE p2;
+DROP PROCEDURE p3;
+DROP PROCEDURE p4;
+
+--disable_warnings
+DROP FUNCTION IF EXISTS f1;
+DROP FUNCTION IF EXISTS f2;
+DROP FUNCTION IF EXISTS f3;
+DROP FUNCTION IF EXISTS f4;
+DROP TABLE IF EXISTS t1;
+--enable_warnings
+
+CREATE TABLE t1 (a CHAR(2));
+
+INSERT INTO t1 VALUES ('aa');
+
+delimiter |;
+CREATE FUNCTION f1() RETURNS CHAR
+  RETURN (SELECT f2())|
+CREATE FUNCTION f2() RETURNS CHAR
+  RETURN (SELECT f3())|
+CREATE FUNCTION f3() RETURNS CHAR
+  RETURN (SELECT f4())|
+CREATE FUNCTION f4() RETURNS CHAR
+BEGIN
+  RETURN (SELECT a FROM t1);
+END|
+delimiter ;|
+
+SELECT f1();
+
+DROP FUNCTION f1;
+DROP FUNCTION f2;
+DROP FUNCTION f3;
+DROP FUNCTION f4;
+DROP TABLE t1;
+
 --echo #
 --echo # Bug#34197: CREATE PROCEDURE fails when COMMENT truncated in non 
 --echo #            strict SQL mode

mysql-test/t/trigger.test

@@ -2425,3 +2425,67 @@ DELETE FROM t1;
 
 DROP TABLE t1;
 DROP TEMPORARY TABLE t2;
+
+#
+# Bug#36649: Condition area is not properly cleaned up after stored routine invocation
+#
+
+--disable_warnings
+DROP TRIGGER IF EXISTS trg1;
+DROP TABLE IF EXISTS t1;
+--enable_warnings
+
+CREATE TABLE t1 (a INT);
+
+delimiter |;
+CREATE TRIGGER trg1 BEFORE INSERT ON t1 FOR EACH ROW
+BEGIN
+  DECLARE a CHAR;
+  SELECT 'ab' INTO a;
+  SELECT 'ab' INTO a;
+  SELECT 'a' INTO a;
+END|
+delimiter ;|
+
+INSERT INTO t1 VALUES (1);
+
+DROP TRIGGER trg1;
+DROP TABLE t1;
+
+#
+# Successive trigger actuations
+#
+
+--disable_warnings
+DROP TRIGGER IF EXISTS trg1;
+DROP TRIGGER IF EXISTS trg2;
+DROP TABLE IF EXISTS t1;
+--enable_warnings
+
+CREATE TABLE t1 (a INT);
+
+delimiter |;
+
+CREATE TRIGGER trg1 BEFORE INSERT ON t1 FOR EACH ROW
+BEGIN
+  DECLARE trg1 CHAR;
+  SELECT 'ab' INTO trg1;
+END|
+
+CREATE TRIGGER trg2 AFTER INSERT ON t1 FOR EACH ROW
+BEGIN
+  DECLARE trg2 CHAR;
+  SELECT 'ab' INTO trg2;
+END|
+
+delimiter ;|
+
+INSERT INTO t1 VALUES (0);
+SELECT * FROM t1;
+SHOW WARNINGS;
+INSERT INTO t1 VALUES (1),(2);
+
+DROP TRIGGER trg1;
+DROP TRIGGER trg2;
+DROP TABLE t1;
+

sql/sp_head.cc

@@ -1083,7 +1083,6 @@ sp_head::execute(THD *thd)
   Item_change_list old_change_list;
   String old_packet;
   Reprepare_observer *save_reprepare_observer= thd->m_reprepare_observer;
-
   Object_creation_ctx *saved_creation_ctx;
   Warning_info *saved_warning_info, warning_info(thd->warning_info->warn_id());
 

sql/sql_parse.cc

@@ -2065,7 +2065,6 @@ mysql_execute_command(THD *thd)
     A better approach would be to reset this for any commands
     that is not a SHOW command or a select that only access local
     variables, but for now this is probably good enough.
-    Don't reset warnings when executing a stored routine.
   */
   if ((sql_command_flags[lex->sql_command] & CF_DIAGNOSTIC_STMT) != 0)
     thd->warning_info->set_read_only(TRUE);