bzr push into mysql-6.0 branch (konstantin:2820 to 2821) Bug#31048, Bug#26180

[Konstantin Osipov]

 2821 Konstantin Osipov	2008-09-03
      Fix a valgrind test suite failure on blade13 (pb-valgrind host).
      The test case for Bug#31048 runs out of stack there in --ps-protocol.
      This is a 64 bit host, and we need a lot of stack there.
modified:
  sql/handler.cc

 2820 Alexander Barkov	2008-09-03
       Bug#26180 Can't add columns to tables created with utf8 (regular) text indexes
            Problem: On ALTER TABLE, maximum possible key part length for TEXT
            variants was calculated similar to VARCHAR datatype, which was wrong
            because TEXT columns are limited in bytes, while VARCHAR columns
            are limited in characters.
            Fix: adding a special code for TEXT variants.
            
            mysql-test/r/ctype_utf8.result
            mysql-test/t/ctype_utf8.test
              Adding test case
            
            sql/sql_table.cc
              Adding special code for TEXT variants.
modified:
  mysql-test/r/ctype_utf8.result
  mysql-test/t/ctype_utf8.test
  sql/sql_table.cc

=== modified file 'sql/handler.cc'
--- a/sql/handler.cc	2008-08-22 11:16:08 +0000
+++ b/sql/handler.cc	2008-09-03 14:40:19 +0000
@@ -4262,6 +4262,13 @@ int DsMrr_impl::dsmrr_init(handler *h, K
 
   /* Create a separate handler object to do rndpos() calls. */
   THD *thd= current_thd;
+
+  /*
+    ::clone() takes up a lot of stack, especially on 64 bit platforms.
+    The constant 5 is an empiric result.
+  */
+  if (check_stack_overrun(thd, 5*STACK_MIN_SIZE, (uchar*) &new_h2))
+    DBUG_RETURN(1);
   if (!(new_h2= h->clone(thd->mem_root)) || 
       new_h2->ha_external_lock(thd, F_RDLCK))
   {