bk commit into 4.1 tree (tnurnberg:1.2538) BUG#21913

[Tatjana A Nuernberg]

Below is the list of changes that have just been committed into a local
4.1 repository of tnurnberg. When tnurnberg does a push these changes will
be propagated to the main repository and, within 24 hours after the
push, to the public repository.
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see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html

ChangeSet@stripped, 2006-09-04 06:16:34+02:00, tnurnberg@stripped +3 -0
  Bug#21913: DATE_FORMAT() Crashes mysql server if I use it through mysql-connector-j
driver.
  
  Variable character_set_results can legally be NULL (for "no conversion.")
  This could result in a NULL deref that crashed the server.  Fixed.
  
  (Although ran some additional precursory tests to see whether I could break
  anything else, but no breakage so far.)

  mysql-test/r/func_time.result@stripped, 2006-09-04 06:16:28+02:00,
tnurnberg@stripped +12 -0
    Bug#21913: DATE_FORMAT() Crashes mysql server if I use it through mysql-connector-j
driver.
    
    Prove DATE_FORMAT() no longer crashes the server when character_set_results is
    NULL (which is a legal value and means, "no conversion").

  mysql-test/t/func_time.test@stripped, 2006-09-04 06:16:28+02:00,
tnurnberg@stripped +18 -0
    Bug#21913: DATE_FORMAT() Crashes mysql server if I use it through mysql-connector-j
driver.
    
    Prove DATE_FORMAT() no longer crashes the server when character_set_results is
    NULL (which is a legal value and means, "no conversion").

  sql/sql_string.cc@stripped, 2006-09-04 06:16:28+02:00,
tnurnberg@stripped +6 -1
    Bug#21913: DATE_FORMAT() Crashes mysql server if I use it through mysql-connector-j
driver.
    
    Avoid NULL deref in my_charset_same() -- if !to_cs, we won't need to compare
    because it is magic for, "no conversion."

# This is a BitKeeper patch.  What follows are the unified diffs for the
# set of deltas contained in the patch.  The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User:	tnurnberg
# Host:	salvation.intern.azundris.com
# Root:	/home/tnurnberg/21913/my41-21913

--- 1.94/sql/sql_string.cc	2006-09-04 06:16:49 +02:00
+++ 1.95/sql/sql_string.cc	2006-09-04 06:16:49 +02:00
@@ -248,6 +248,10 @@ bool String::copy(const char *str,uint32
    0  No conversion needed
    1  Either character set conversion or adding leading  zeros
       (e.g. for UCS-2) must be done
+
+  NOTE
+  to_cs may be NULL for "no conversion" if the system variable
+  character_set_results is NULL.
 */
 
 bool String::needs_conversion(uint32 arg_length,
@@ -256,7 +260,8 @@ bool String::needs_conversion(uint32 arg
 			      uint32 *offset)
 {
   *offset= 0;
-  if ((to_cs == &my_charset_bin) || 
+  if (!to_cs ||
+      (to_cs == &my_charset_bin) || 
       (to_cs == from_cs) ||
       my_charset_same(from_cs, to_cs) ||
       ((from_cs == &my_charset_bin) &&

--- 1.42/mysql-test/r/func_time.result	2006-09-04 06:16:49 +02:00
+++ 1.43/mysql-test/r/func_time.result	2006-09-04 06:16:49 +02:00
@@ -688,3 +688,15 @@ t1	CREATE TABLE `t1` (
   `from_unixtime(1) + 0` double(23,6) default NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
+SET NAMES latin1;
+SET character_set_results = NULL;
+SHOW VARIABLES LIKE 'character_set_results';
+Variable_name	Value
+character_set_results	
+CREATE TABLE testBug8868 (field1 DATE, field2 VARCHAR(32) CHARACTER SET BINARY);
+INSERT INTO testBug8868 VALUES ('2006-09-04', 'abcd');
+SELECT DATE_FORMAT(field1,'%b-%e %l:%i%p') as fmtddate, field2 FROM testBug8868;
+fmtddate	field2
+Sep-4 12:00AM	abcd
+DROP TABLE testBug8868;
+SET NAMES DEFAULT;

--- 1.37/mysql-test/t/func_time.test	2006-09-04 06:16:49 +02:00
+++ 1.38/mysql-test/t/func_time.test	2006-09-04 06:16:49 +02:00
@@ -358,4 +358,22 @@ create table t1 select now() - now(), cu
 show create table t1;
 drop table t1;
 
+#
+# 21913: DATE_FORMAT() Crashes mysql server if I use it through
+#        mysql-connector-j driver.
+#
+
+SET NAMES latin1;
+SET character_set_results = NULL;
+SHOW VARIABLES LIKE 'character_set_results';
+
+CREATE TABLE testBug8868 (field1 DATE, field2 VARCHAR(32) CHARACTER SET BINARY);
+INSERT INTO testBug8868 VALUES ('2006-09-04', 'abcd');
+
+SELECT DATE_FORMAT(field1,'%b-%e %l:%i%p') as fmtddate, field2 FROM testBug8868;
+
+DROP TABLE testBug8868;
+
+SET NAMES DEFAULT;
+
 # End of 4.1 tests