Fix for

bug#33094: Error in upgrading from 5.0 to 5.1 when table contains
triggers
and
#41385: Crash when attempting to repair a #mysql50# upgraded table
with triggers.

Problem:
1. trigger code didn't assume a table name may have
a "#mysql50#" prefix, that may lead to a failing ASSERT().
2. "ALTER DATABASE ... UPGRADE DATA DIRECTORY NAME" failed
for databases with "#mysql50#" prefix if any trigger.
3. mysqlcheck --fix-table-name didn't use UTF8 as a default
character set that resulted in (parsing) errors for tables with
non-latin symbols in their names and definitions of triggers.

Fix:
1. properly handle table/database names with "#mysql50#" prefix.
2. handle --default-character-set mysqlcheck option;
if mysqlcheck is launched with --fix-table-name or --fix-db-name
set default character set to UTF8 if no --default-character-set
option given.

Note: if given --fix-table-name or --fix-db-name option,
without --default-character-set mysqlcheck option
default character set is UTF8.


client/mysqlcheck.c:
  Fix for
  bug#33094: Error in upgrading from 5.0 to 5.1 when table contains
  triggers
  and
  #41385: Crash when attempting to repair a #mysql50# upgraded table
  with triggers.
    - check and set default charset if --default-character-set option
      given.
    - set default charset to "utf8" if there's
      --fix-table-name or --fix-db-name and no --default-character-set.
mysql-test/r/mysqlcheck.result:
  Fix for
  bug#33094: Error in upgrading from 5.0 to 5.1 when table contains
  triggers
  and
  #41385: Crash when attempting to repair a #mysql50# upgraded table
  with triggers.
    - test result.
mysql-test/t/mysqlcheck.test:
  Fix for
  bug#33094: Error in upgrading from 5.0 to 5.1 when table contains
  triggers
  and
  #41385: Crash when attempting to repair a #mysql50# upgraded table
  with triggers.
    - test case.
sql/mysql_priv.h:
  Fix for
  bug#33094: Error in upgrading from 5.0 to 5.1 when table contains
  triggers
  and
  #41385: Crash when attempting to repair a #mysql50# upgraded table
  with triggers.
    - check_n_cut_mysql50_prefix() introduced.
sql/sql_table.cc:
  Fix for
  bug#33094: Error in upgrading from 5.0 to 5.1 when table contains
  triggers
  and
  #41385: Crash when attempting to repair a #mysql50# upgraded table
  with triggers.
    - tablename_to_filename() code split into 2 parts
    - check_n_cut_mysql50_prefix() introduced to cut #mysql50# prefixes,
      used in the trigger code as well.
sql/sql_trigger.cc:
  Fix for
  bug#33094: Error in upgrading from 5.0 to 5.1 when table contains
  triggers
  and
  #41385: Crash when attempting to repair a #mysql50# upgraded table
  with triggers.
    - Table_triggers_list::check_n_load() - checking triggers assume
      a table/database name given may have "#mysql50#" prefix in some cases.
    - Table_triggers_list::change_table_name_in_triggers() -
      create .TRG file in new database directory and delete it in old one,
      as they may differ in case of
      "ALTER DATABASE ... UPGRADE DATA DIRECTORY NAME"
    - Table_triggers_list::change_table_name_in_trignames() - remove stale .TRN
      files in #mysql50#dbname directory in case of database upgrade
    - Table_triggers_list::change_table_name() - allow changing trigger's
      database in case of its upgrading
sql/sql_trigger.h:
  Fix for
  bug#33094: Error in upgrading from 5.0 to 5.1 when table contains
  triggers
  and
  #41385: Crash when attempting to repair a #mysql50# upgraded table
  with triggers.
    - new old_db_name parameter added in
      Table_triggers_list::change_table_name_in_trignames() and
      Table_triggers_list::change_table_name_in_triggers()

1 files changed, 26 insertions, 5 deletions

diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index 224cf1123e2..3ec03be72a5 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -114,6 +114,30 @@ uint filename_to_tablename(const char *from, char *to, uint to_length)
 }
 
 
+/**
+  Check if given string begins with "#mysql50#" prefix, cut it if so.
+  
+  @param   from          string to check and cut 
+  @param   to[out]       buffer for result string
+  @param   to_length     its size
+  
+  @retval
+    0      no prefix found
+  @retval
+    non-0  result string length
+*/
+
+uint check_n_cut_mysql50_prefix(const char *from, char *to, uint to_length)
+{
+  if (from[0] == '#' && 
+      !strncmp(from, MYSQL50_TABLE_NAME_PREFIX,
+               MYSQL50_TABLE_NAME_PREFIX_LENGTH))
+    return (uint) (strmake(to, from + MYSQL50_TABLE_NAME_PREFIX_LENGTH,
+                           to_length - 1) - to);
+  return 0;
+}
+
+
 /*
   Translate a table name to a file name (WL #1324).
 
@@ -133,11 +157,8 @@ uint tablename_to_filename(const char *from, char *to, uint to_length)
   DBUG_ENTER("tablename_to_filename");
   DBUG_PRINT("enter", ("from '%s'", from));
 
-  if (from[0] == '#' && !strncmp(from, MYSQL50_TABLE_NAME_PREFIX,
-                                 MYSQL50_TABLE_NAME_PREFIX_LENGTH))
-    DBUG_RETURN((uint) (strmake(to, from+MYSQL50_TABLE_NAME_PREFIX_LENGTH,
-                                to_length-1) -
-                        (from + MYSQL50_TABLE_NAME_PREFIX_LENGTH)));
+  if ((length= check_n_cut_mysql50_prefix(from, to, to_length)))
+    DBUG_RETURN(length);
   length= strconvert(system_charset_info, from,
                      &my_charset_filename, to, to_length, &errors);
   if (check_if_legal_tablename(to) &&