Fix for:

bug #26215: mysql command line client should not strip comments
              from SQL statements
and
  bug #11230: Keeping comments when storing stored procedures

With the introduction of multiline comments support in the command line
client (mysql) in MySQL 4.1, it became impossible to preserve
client-side comments within single SQL statements or stored routines.
This feature was useful for monitoring tools and maintenance.

The patch adds a new option to the command line client
('--enable-comments', '-c') which allows to preserve SQL comments and
send them to the server for single SQL statements, and to keep comments
in the code for stored procedures / functions / triggers.

The patch is a modification of the contributed patch from bug #11230
with the following changes:
- code style changes to conform to the coding guidelines
- changed is_prefix() to my_strnncoll() to detect the DELIMITER
command, since the first one is case-sensitive and not charset-aware
- renamed t/comments-51.* to t/mysql_comments.*
- removed tests for comments in triggers since 5.0 does not have SHOW
CREATE TRIGGER (those tests will be added back in 5.1).

The test cases are only for bug #11230. No automated test case for bug
#26215 is possible due to the test suite deficiencies (though the cases
from the bug report were tested manually).

mysql-test/r/mysql_comments.result

@@ -0,0 +1,50 @@
+drop table if exists t1;
+drop function if exists foofct;
+drop procedure if exists empty;
+drop procedure if exists foosp;
+drop procedure if exists nicesp;
+drop trigger if exists t1_empty;
+drop trigger if exists t1_bi;
+"Pass 1 : --disable-comments"
+1
+1
+2
+2
+foofct("call 1")
+call 1
+Function	sql_mode	Create Function
+foofct		CREATE DEFINER=`root`@`localhost` FUNCTION `foofct`(x char(20)) RETURNS char(20) CHARSET latin1\nreturn\n\n\n\nx
+foofct("call 2")
+call 2
+Function	sql_mode	Create Function
+foofct		CREATE DEFINER=`root`@`localhost` FUNCTION `foofct`(x char(20)) RETURNS char(20) CHARSET latin1\nbegin\n  \n  \n  \n\n  \n\n  \n  return x;\nend
+Procedure	sql_mode	Create Procedure
+empty		CREATE DEFINER=`root`@`localhost` PROCEDURE `empty`()\nbegin\nend
+id	data
+foo	42
+Procedure	sql_mode	Create Procedure
+foosp		CREATE DEFINER=`root`@`localhost` PROCEDURE `foosp`()\ninsert into test.t1\n\n\n\n\n  \n\n  \n  values ("foo", 42)
+Procedure	sql_mode	Create Procedure
+nicesp		CREATE DEFINER=`root`@`localhost` PROCEDURE `nicesp`(a int)\nbegin\n  \n  declare b int;\n  declare c float;\n\n  \n  \n\n  \nend
+"Pass 2 : --enable-comments"
+1
+1
+2
+2
+foofct("call 1")
+call 1
+Function	sql_mode	Create Function
+foofct		CREATE DEFINER=`root`@`localhost` FUNCTION `foofct`(x char(20)) RETURNS char(20) CHARSET latin1\nreturn\n-- comment 1a\n# comment 1b\n/* comment 1c */\nx # after body, on same line
+foofct("call 2")
+call 2
+Function	sql_mode	Create Function
+foofct		CREATE DEFINER=`root`@`localhost` FUNCTION `foofct`(x char(20)) RETURNS char(20) CHARSET latin1\nbegin\n  -- comment 1a\n  # comment 1b\n  /*\n     comment 1c\n  */\n\n  -- empty line below\n\n  -- empty line above\n  return x;\nend
+Procedure	sql_mode	Create Procedure
+empty		CREATE DEFINER=`root`@`localhost` PROCEDURE `empty`()\nbegin\nend
+id	data
+foo	42
+Procedure	sql_mode	Create Procedure
+foosp		CREATE DEFINER=`root`@`localhost` PROCEDURE `foosp`()\ninsert into test.t1\n## These comments are part of the procedure body, and should be kept.\n# Comment 2a\n-- Comment 2b\n/* Comment 2c */\n  -- empty line below\n\n  -- empty line above\n  values ("foo", 42) # comment 3, still part of the body
+Procedure	sql_mode	Create Procedure
+nicesp		CREATE DEFINER=`root`@`localhost` PROCEDURE `nicesp`(a int)\nbegin\n  -- declare some variables here\n  declare b int;\n  declare c float;\n\n  -- do more stuff here\n  -- commented nicely and so on\n\n  -- famous last words ...\nend
+End of 5.0 tests