WL#1324 table name to file name encoding

- Encoding itself, implemented as a charset
  "filename". Originally planned to use '.'
  as an escape character, but now changed to '@'
  for two reasons: "ls" does not return
  file names starting with '.' considering them
  as a kind of hidden files; some platforms
  do not allow several dots in a file name.
- replacing many calls of my_snprintf() and
  strnxmov() to the new build_table_filename().
- Adding MY_APPEND_EXT mysys flag, to append
  an extention rather that replace it.
- Replacing all numeric constants in fn_format
  flag arguments to their mysys definitions, e.g.
  MY_UNPACK_FILENAME,
- Predictability in several function/methods:
  when a table name can appear with or withot .frm
  extension. Some functions/methods were changed
  so accept names strictly with .frm, other - strictly
  without .frm extensions. Several DBUG_ASSERTs were
  added to check whether an extension is passed.
Many files:
  table name to file name encoding
mysql_priv.h:
  Prototypes for new table name encoding tools.
ctype-utf8.c:
  Implementing "filename" charset for
  table name to file name encoding.
row0mysql.c:
  Fixing table name prefix.
mf_format.c:
  Adding MY_APPEND_EXT processing.
Many files:
  Fixing tests.
my_sys.h:
  Adding new flag to append rather than replace an extension.
m_ctype.h:
  Adding "filename" charset definition.

24 files changed, 392 insertions, 204 deletions

diff --git a/sql/discover.cc b/sql/discover.cc
index 1251055c70e..2a3da55f154 100644
--- a/sql/discover.cc
+++ b/sql/discover.cc
@@ -55,7 +55,8 @@ int readfrm(const char *name,
   *frmdata= NULL;      // In case of errors
   *len= 0;
   error= 1;
-  if ((file=my_open(fn_format(index_file,name,"",reg_ext,4),
+  if ((file=my_open(fn_format(index_file,name,"",reg_ext,
+                              MY_UNPACK_FILENAME|MY_APPEND_EXT),
 		    O_RDONLY | O_SHARE,
 		    MYF(0))) < 0)  
     goto err_end; 
@@ -112,7 +113,8 @@ int writefrm(const char *name, const void *frmdata, uint len)
   //DBUG_DUMP("frmdata", (char*)frmdata, len);
 
   error= 0;
-  if ((file=my_create(fn_format(index_file,name,"",reg_ext,4),
+  if ((file=my_create(fn_format(index_file,name,"",reg_ext,
+                      MY_UNPACK_FILENAME|MY_APPEND_EXT),
 		      CREATE_MODE,O_RDWR | O_TRUNC,MYF(MY_WME))) >= 0)
   {
     if (my_write(file,(byte*)frmdata,len,MYF(MY_WME | MY_NABP)))
diff --git a/sql/ha_berkeley.cc b/sql/ha_berkeley.cc
index 900372a2204..01d6ceed3f2 100644
--- a/sql/ha_berkeley.cc
+++ b/sql/ha_berkeley.cc
@@ -699,7 +699,7 @@ int ha_berkeley::open(const char *name, int mode, uint test_if_locked)
     if ((error= db_env->txn_begin(db_env, NULL, (DB_TXN**) &transaction, 0)) ||
 	(error= (file->open(file, transaction,
 			    fn_format(name_buff, name, "", ha_berkeley_ext,
-				      2 | 4),
+				      MY_UNPACK_FILENAME|MY_APPEND_EXT),
 			    "main", DB_BTREE, open_mode, 0))) ||
 	(error= transaction->commit(transaction, 0)))
     {
@@ -2093,7 +2093,8 @@ int ha_berkeley::create(const char *name, register TABLE *form,
   int error;
   DBUG_ENTER("ha_berkeley::create");
 
-  fn_format(name_buff,name,"", ha_berkeley_ext,2 | 4);
+  fn_format(name_buff,name,"", ha_berkeley_ext,
+            MY_UNPACK_FILENAME|MY_APPEND_EXT);
 
   /* Create the main table that will hold the real rows */
   if ((error= create_sub_table(name_buff,"main",DB_BTREE,0)))
@@ -2142,8 +2143,9 @@ int ha_berkeley::delete_table(const char *name)
   if ((error=db_create(&file, db_env, 0)))
     my_errno=error; /* purecov: inspected */
   else
-    error=file->remove(file,fn_format(name_buff,name,"",ha_berkeley_ext,2 | 4),
-		       NULL,0);
+    error=file->remove(file,fn_format(name_buff,name,"",ha_berkeley_ext,
+                                      MY_UNPACK_FILENAME|MY_APPEND_EXT),
+                       NULL,0);
   file=0;					// Safety
   DBUG_RETURN(error);
 }
@@ -2161,9 +2163,11 @@ int ha_berkeley::rename_table(const char * from, const char * to)
   {
     /* On should not do a file->close() after rename returns */
     error= file->rename(file, 
-			fn_format(from_buff, from, "", ha_berkeley_ext, 2 | 4),
+			fn_format(from_buff, from, "", 
+                                  ha_berkeley_ext,
+                                  MY_UNPACK_FILENAME|MY_APPEND_EXT),
 			NULL, fn_format(to_buff, to, "", ha_berkeley_ext,
-					2 | 4), 0);
+                                        MY_UNPACK_FILENAME|MY_APPEND_EXT), 0);
   }
   return error;
 }
@@ -2413,7 +2417,8 @@ int ha_berkeley::check(THD* thd, HA_CHECK_OPT* check_opt)
 			   (hidden_primary_key ? berkeley_cmp_hidden_key :
 			    berkeley_cmp_packed_key));
   tmp_file->app_private= (void*) (table->key_info+table->primary_key);
-  fn_format(name_buff,share->table_name.str,"", ha_berkeley_ext, 2 | 4);
+  fn_format(name_buff,share->table_name.str,"", ha_berkeley_ext,
+            MY_UNPACK_FILENAME|MY_APPEND_EXT);      
   if ((error=tmp_file->verify(tmp_file, name_buff, NullS, (FILE*) 0,
 			      hidden_primary_key ? 0 : DB_NOORDERCHK)))
   {
@@ -2559,7 +2564,8 @@ void ha_berkeley::get_status()
       char name_buff[FN_REFLEN];
       uint open_mode= (((table->db_stat & HA_READ_ONLY) ? DB_RDONLY : 0)
 		       | DB_THREAD);
-      fn_format(name_buff, share->table_name, "", ha_berkeley_ext, 2 | 4);
+      fn_format(name_buff, share->table_name, "", ha_berkeley_ext,
+                MY_UNPACK_FILENAME|MY_APPEND_EXT);
       if (!db_create(&share->status_block, db_env, 0))
       {
 	if (share->status_block->open(share->status_block, NULL, name_buff,
@@ -2641,7 +2647,8 @@ static void update_status(BDB_SHARE *share, TABLE *table)
       share->status_block->set_flags(share->status_block,0); /* purecov: inspected */
       if (share->status_block->open(share->status_block, NULL,
 				    fn_format(name_buff,share->table_name,
-                                              "", ha_berkeley_ext,2 | 4),
+                                              "", ha_berkeley_ext,
+                                              MY_UNPACK_FILENAME|MY_APPEND_EXT),
 				    "status", DB_BTREE,
 				    DB_THREAD | DB_CREATE, my_umask)) /* purecov: inspected */
 	goto end; /* purecov: inspected */
diff --git a/sql/ha_innodb.cc b/sql/ha_innodb.cc
index 7909f39154f..27262e6f197 100644
--- a/sql/ha_innodb.cc
+++ b/sql/ha_innodb.cc
@@ -4857,7 +4857,7 @@ ha_innobase::create(
 		srv_lower_case_table_names = FALSE;
 	}
 
-	fn_format(name2, name, "", "", 2);	// Remove the .frm extension
+	strcpy(name2, name);
 
 	normalize_table_name(norm_name, name2);
 
diff --git a/sql/ha_myisam.cc b/sql/ha_myisam.cc
index 5fe82e9ccae..41000564e53 100644
--- a/sql/ha_myisam.cc
+++ b/sql/ha_myisam.cc
@@ -539,8 +539,8 @@ int ha_myisam::backup(THD* thd, HA_CHECK_OPT *check_opt)
   }
 
   /* Change extension */
-  if (!fn_format(dst_path, dst_path, "", MI_NAME_DEXT,
-		 MY_REPLACE_EXT | MY_UNPACK_FILENAME | MY_SAFE_PATH))
+  if (fn_format_relative_to_data_home(dst_path, table_name, backup_dir,
+                                      MI_NAME_DEXT))
   {
     errmsg = "Failed in fn_format() for .MYD file (errno: %d)";
     error = HA_ADMIN_INVALID;
@@ -1361,10 +1361,10 @@ void ha_myisam::info(uint flag)
      if table is symlinked (Ie;  Real name is not same as generated name)
    */
     data_file_name= index_file_name= 0;
-    fn_format(name_buff, file->filename, "", MI_NAME_DEXT, 2);
+    fn_format(name_buff, file->filename, "", MI_NAME_DEXT, MY_APPEND_EXT);
     if (strcmp(name_buff, info.data_file_name))
       data_file_name=info.data_file_name;
-    strmov(fn_ext(name_buff),MI_NAME_IEXT);
+    fn_format(name_buff, file->filename, "", MI_NAME_IEXT, MY_APPEND_EXT);
     if (strcmp(name_buff, info.index_file_name))
       index_file_name=info.index_file_name;
   }
@@ -1647,7 +1647,7 @@ int ha_myisam::create(const char *name, register TABLE *table_arg,
     create_flags|= HA_CREATE_DELAY_KEY_WRITE;
 
   /* TODO: Check that the following fn_format is really needed */
-  error=mi_create(fn_format(buff,name,"","",2+4),
+  error=mi_create(fn_format(buff,name,"","",MY_UNPACK_FILENAME|MY_APPEND_EXT),
 		  share->keys,keydef,
 		  (uint) (recinfo_pos-recinfo), recinfo,
 		  0, (MI_UNIQUEDEF*) 0,
diff --git a/sql/ha_myisammrg.cc b/sql/ha_myisammrg.cc
index 1be4fb62fa1..ccb3475e34f 100644
--- a/sql/ha_myisammrg.cc
+++ b/sql/ha_myisammrg.cc
@@ -105,8 +105,9 @@ int ha_myisammrg::open(const char *name, int mode, uint test_if_locked)
   char name_buff[FN_REFLEN];
 
   DBUG_PRINT("info", ("ha_myisammrg::open"));
-  if (!(file=myrg_open(fn_format(name_buff,name,"","",2 | 4), mode,
-		       test_if_locked)))
+  if (!(file=myrg_open(fn_format(name_buff,name,"","",
+                                 MY_UNPACK_FILENAME|MY_APPEND_EXT),
+                       mode, test_if_locked)))
   {
     DBUG_PRINT("info", ("ha_myisammrg::open exit %d", my_errno));
     return (my_errno ? my_errno : -1);
@@ -469,8 +470,8 @@ int ha_myisammrg::create(const char *name, register TABLE *form,
         This means that it might not be possible to move the DATADIR of
         an embedded server without changing the paths in the .MRG file.
       */
-      uint length= my_snprintf(buff, FN_REFLEN, "%s/%s/%s", mysql_data_home,
-			       tables->db, tables->table_name);
+      uint length= build_table_filename(buff, sizeof(buff),
+                                        tables->db, tables->table_name, "");
       /*
         If a MyISAM table is in the same directory as the MERGE table,
         we use the table name without a path. This means that the
@@ -488,7 +489,9 @@ int ha_myisammrg::create(const char *name, register TABLE *form,
     *pos++= table_name;
   }
   *pos=0;
-  DBUG_RETURN(myrg_create(fn_format(buff,name,"","",2+4+16),
+  DBUG_RETURN(myrg_create(fn_format(buff,name,"","",
+                                    MY_RESOLVE_SYMLINKS|
+                                    MY_UNPACK_FILENAME|MY_APPEND_EXT),
 			  table_names,
                           create_info->merge_insert_method,
                           (my_bool) 0));
diff --git a/sql/ha_ndbcluster.cc b/sql/ha_ndbcluster.cc
index 31548ef0d61..dfbe1993ea8 100644
--- a/sql/ha_ndbcluster.cc
+++ b/sql/ha_ndbcluster.cc
@@ -3961,7 +3961,8 @@ int ha_ndbcluster::create(const char *name,
   DBUG_ENTER("ha_ndbcluster::create");
   DBUG_PRINT("enter", ("name: %s", name));
 
-  fn_format(name2, name, "", "",2);       // Remove the .frm extension
+  strcpy(name2, name);
+  DBUG_ASSERT(*fn_rext((char*)name2) == 0);
   set_dbname(name2);
   set_tabname(name2);    
 
diff --git a/sql/ha_partition.cc b/sql/ha_partition.cc
index 3b8f26d88f2..4784a0c7530 100644
--- a/sql/ha_partition.cc
+++ b/sql/ha_partition.cc
@@ -399,7 +399,8 @@ int ha_partition::create(const char *name, TABLE *table_arg,
   DBUG_ENTER("ha_partition::create");
 
   strmov(t_name, name);
-  *fn_ext(t_name)= 0;
+//  *fn_ext(t_name)= 0;
+  DBUG_ASSERT(*fn_rext((char*)name) == '\0');
   if (del_ren_cre_table(t_name, NULL, table_arg, create_info))
   {
     handler::delete_table(t_name);
@@ -677,7 +678,7 @@ bool ha_partition::create_handler_file(const char *name)
     Create and write and close file
     to be used at open, delete_table and rename_table
   */
-  fn_format(file_name, name, "", ".par", MYF(MY_REPLACE_EXT));
+  fn_format(file_name, name, "", ".par", MY_APPEND_EXT);
   if ((file= my_create(file_name, CREATE_MODE, O_RDWR | O_TRUNC,
 		       MYF(MY_WME))) >= 0)
   {
@@ -802,7 +803,7 @@ bool ha_partition::get_from_handler_file(const char *name)
 
   if (m_file_buffer)
     DBUG_RETURN(FALSE);
-  fn_format(buff, name, "", ha_par_ext, MYF(0));
+  fn_format(buff, name, "", ha_par_ext, MY_APPEND_EXT);
 
   /* Following could be done with my_stat to read in whole file */
   if ((file= my_open(buff, O_RDONLY | O_SHARE, MYF(0))) < 0)
diff --git a/sql/handler.cc b/sql/handler.cc
index 59445a1b2f1..db97b14da2a 100644
--- a/sql/handler.cc
+++ b/sql/handler.cc
@@ -2023,7 +2023,7 @@ int handler::delete_table(const char *name)
 
   for (const char **ext=bas_ext(); *ext ; ext++)
   {
-    fn_format(buff, name, "", *ext, 2 | 4);
+    fn_format(buff, name, "", *ext, MY_UNPACK_FILENAME|MY_APPEND_EXT);
     if (my_delete_with_symlink(buff, MYF(0)))
     {
       if ((error= my_errno) != ENOENT)
diff --git a/sql/init.cc b/sql/init.cc
index e53eeab8902..9f975296cb6 100644
--- a/sql/init.cc
+++ b/sql/init.cc
@@ -39,6 +39,7 @@ void unireg_init(ulong options)
 #endif
 
   VOID(strmov(reg_ext,".frm"));
+  reg_ext_length= 4;
   specialflag=SPECIAL_SAME_DB_NAME | options;  /* Set options from argv */
   /* Make a tab of powers of 10 */
   for (i=0,nr=1.0; i < array_elements(log_10) ; i++)
diff --git a/sql/mysql_priv.h b/sql/mysql_priv.h
index c815cb22495..fabc2e2e1cd 100644
--- a/sql/mysql_priv.h
+++ b/sql/mysql_priv.h
@@ -1174,6 +1174,7 @@ extern Lt_creator lt_creator;
 extern Ge_creator ge_creator;
 extern Le_creator le_creator;
 extern char language[FN_REFLEN], reg_ext[FN_EXTLEN];
+extern uint reg_ext_length;
 extern char glob_hostname[FN_REFLEN], mysql_home[FN_REFLEN];
 extern char pidfile_name[FN_REFLEN], system_time_zone[30], *opt_init_file;
 extern char log_error_file[FN_REFLEN], *opt_tc_log_file;
@@ -1499,6 +1500,23 @@ bool check_table_name(const char *name, uint length);
 char *get_field(MEM_ROOT *mem, Field *field);
 bool get_field(MEM_ROOT *mem, Field *field, class String *res);
 int wild_case_compare(CHARSET_INFO *cs, const char *str,const char *wildstr);
+char *fn_rext(char *name);
+
+/* Conversion functions */
+uint strconvert(CHARSET_INFO *from_cs, const char *from,
+                CHARSET_INFO *to_cs, char *to, uint to_length);
+uint build_table_filename(char *buff, size_t bufflen, const char *db,
+                          const char *table, const char *ext);
+inline uint filename_to_tablename(const char *from, char *to, uint to_length)
+{
+  return strconvert(&my_charset_filename, from,
+                    system_charset_info, to, to_length);
+}
+inline uint tablename_to_filename(const char *from, char *to, uint to_length)
+{
+  return strconvert(system_charset_info, from,
+                    &my_charset_filename, to, to_length);
+}
 
 /* from hostname.cc */
 struct in_addr;
diff --git a/sql/mysqld.cc b/sql/mysqld.cc
index 7e25ea51823..6bceb51809e 100644
--- a/sql/mysqld.cc
+++ b/sql/mysqld.cc
@@ -511,7 +511,7 @@ char mysql_real_data_home[FN_REFLEN],
      language[FN_REFLEN], reg_ext[FN_EXTLEN], mysql_charsets_dir[FN_REFLEN],
      *opt_init_file, *opt_tc_log_file,
      def_ft_boolean_syntax[sizeof(ft_boolean_syntax)];
-
+uint reg_ext_length;
 const key_map key_map_empty(0);
 key_map key_map_full(0);                        // Will be initialized later
 
@@ -7455,7 +7455,7 @@ fn_format_relative_to_data_home(my_string to, const char *name,
     dir=tmp_path;
   }
   return !fn_format(to, name, dir, extension,
-		    MY_REPLACE_EXT | MY_UNPACK_FILENAME | MY_SAFE_PATH);
+		    MY_APPEND_EXT | MY_UNPACK_FILENAME | MY_SAFE_PATH);
 }
 
 
diff --git a/sql/parse_file.cc b/sql/parse_file.cc
index fe82054c528..0b2bfe83b6f 100644
--- a/sql/parse_file.cc
+++ b/sql/parse_file.cc
@@ -226,8 +226,20 @@ sql_create_definition_file(const LEX_STRING *dir, const LEX_STRING *file_name,
   DBUG_PRINT("enter", ("Dir: %s, file: %s, base 0x%lx",
 		       dir->str, file_name->str, (ulong) base));
 
-  fn_format(path, file_name->str, dir->str, 0, MY_UNPACK_FILENAME);
-  path_end= strlen(path);
+  if (dir)
+  {
+    fn_format(path, file_name->str, dir->str, 0, MY_UNPACK_FILENAME);
+    path_end= strlen(path);
+  }
+  else
+  {
+    /*
+      if not dir is passed, it means file_name is a full path,
+      including dir name, file name itself, and an extension,
+      and with unpack_filename() executed over it.
+    */    
+    path_end= strxnmov(path, FN_REFLEN, file_name->str, NullS) - path;
+  }
 
   // temporary file name
   path[path_end]='~';
diff --git a/sql/sql_acl.cc b/sql/sql_acl.cc
index 4d12922f75d..f24b30729b1 100644
--- a/sql/sql_acl.cc
+++ b/sql/sql_acl.cc
@@ -2796,9 +2796,10 @@ bool mysql_table_grant(THD *thd, TABLE_LIST *table_list,
       if (!(rights & CREATE_ACL))
       {
         char buf[FN_REFLEN];
-        sprintf(buf,"%s/%s/%s.frm",mysql_data_home, table_list->db,
-                table_list->table_name);
-        fn_format(buf,buf,"","",4+16+32);
+        build_table_filename(buf, sizeof(buf), table_list->db,
+                             table_list->table_name, reg_ext);
+        fn_format(buf, buf, "", "", MY_UNPACK_FILENAME  | MY_RESOLVE_SYMLINKS |
+                                    MY_RETURN_REAL_PATH | MY_APPEND_EXT);
         if (access(buf,F_OK))
         {
           my_error(ER_NO_SUCH_TABLE, MYF(0), table_list->db, table_list->alias);
diff --git a/sql/sql_base.cc b/sql/sql_base.cc
index 032cf485862..c1fad0a9bbf 100644
--- a/sql/sql_base.cc
+++ b/sql/sql_base.cc
@@ -1819,9 +1819,8 @@ TABLE *open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
     {
       char path[FN_REFLEN];
       enum legacy_db_type not_used;
-      strxnmov(path, FN_REFLEN-1, mysql_data_home, "/", table_list->db, "/",
-               table_list->table_name, reg_ext, NullS);
-      (void) unpack_filename(path, path);
+      build_table_filename(path, sizeof(path) - 1,
+                           table_list->db, table_list->table_name, reg_ext);
       if (mysql_frm_type(thd, path, &not_used) == FRMTYPE_VIEW)
       {
         /*
diff --git a/sql/sql_db.cc b/sql/sql_db.cc
index 0e6c0c45cf1..d91f091174f 100644
--- a/sql/sql_db.cc
+++ b/sql/sql_db.cc
@@ -425,8 +425,7 @@ bool mysql_create_db(THD *thd, char *db, HA_CREATE_INFO *create_info,
   }
 
   /* Check directory */
-  strxmov(path, mysql_data_home, "/", db, NullS);
-  path_len= unpack_dirname(path,path);    // Convert if not unix
+  path_len= build_table_filename(path, sizeof(path), db, "", "");
   path[path_len-1]= 0;                    // Remove last '/' from path
 
   if (my_stat(path,&stat_info,MYF(0)))
@@ -549,9 +548,12 @@ bool mysql_alter_db(THD *thd, const char *db, HA_CREATE_INFO *create_info)
   if ((error=wait_if_global_read_lock(thd,0,1)))
     goto exit2;
 
-  /* Check directory */
-  strxmov(path, mysql_data_home, "/", db, "/", MY_DB_OPT_FILE, NullS);
-  fn_format(path, path, "", "", MYF(MY_UNPACK_FILENAME));
+  /* 
+     Recreate db options file: /dbpath/.db.opt
+     We pass MY_DB_OPT_FILE as "extension" to avoid
+     "table name to file name" encoding.
+  */
+  build_table_filename(path, sizeof(path), db, "", MY_DB_OPT_FILE);
   if ((error=write_db_opt(thd, path, create_info)))
     goto exit;
 
@@ -629,8 +631,7 @@ bool mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent)
     goto exit2;
   }
 
-  (void) sprintf(path,"%s/%s",mysql_data_home,db);
-  length= unpack_dirname(path,path);		// Convert if not unix
+  length= build_table_filename(path, sizeof(path), db, "", "");
   strmov(path+length, MY_DB_OPT_FILE);		// Append db option file name
   del_dbopt(path);				// Remove dboption hash entry
   path[length]= '\0';				// Remove file name
@@ -852,7 +853,8 @@ static long mysql_rm_known_files(THD *thd, MY_DIR *dirp, const char *db,
       found_other_files++;
       continue;
     }
-    extension= fn_ext(file->name);
+    if (!(extension= strrchr(file->name, '.')))
+      extension= strend(file->name);
     if (find_type(extension, &deletable_extentions,1+2) <= 0)
     {
       if (find_type(extension, ha_known_exts(),1+2) <= 0)
@@ -870,7 +872,9 @@ static long mysql_rm_known_files(THD *thd, MY_DIR *dirp, const char *db,
       if (!table_list)
 	goto err;
       table_list->db= (char*) (table_list+1);
-      strmov(table_list->table_name= strmov(table_list->db,db)+1, file->name);
+      table_list->table_name= strmov(table_list->db, db) + 1;
+      VOID(filename_to_tablename(file->name, table_list->table_name,
+                                 strlen(file->name) + 1));
       table_list->alias= table_list->table_name;	// If lower_case_table_names=2
       /* Link into list */
       (*tot_list_next)= table_list;
@@ -1151,8 +1155,7 @@ bool mysql_change_db(THD *thd, const char *name, bool no_access_check)
     }
   }
 #endif
-  (void) sprintf(path,"%s/%s",mysql_data_home,dbname);
-  length=unpack_dirname(path,path);		// Convert if not unix
+  length= build_table_filename(path, sizeof(path), dbname, "", "");
   if (length && path[length-1] == FN_LIBCHAR)
     path[length-1]=0;				// remove ending '\'
   if (my_access(path,F_OK))
diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc
index 66644abe9e3..ba1cce3abfe 100644
--- a/sql/sql_delete.cc
+++ b/sql/sql_delete.cc
@@ -837,6 +837,7 @@ bool mysql_truncate(THD *thd, TABLE_LIST *table_list, bool dont_send_ok)
   char path[FN_REFLEN];
   TABLE *table;
   bool error;
+  uint path_length;
   DBUG_ENTER("mysql_truncate");
 
   bzero((char*) &create_info,sizeof(create_info));
@@ -867,9 +868,8 @@ bool mysql_truncate(THD *thd, TABLE_LIST *table_list, bool dont_send_ok)
     goto end;
   }
 
-  (void) sprintf(path,"%s/%s/%s%s",mysql_data_home,table_list->db,
-		 table_list->table_name,reg_ext);
-  fn_format(path, path, "", "", MY_UNPACK_FILENAME);
+  path_length= build_table_filename(path, sizeof(path), table_list->db,
+                                    table_list->table_name, reg_ext);
 
   if (!dont_send_ok)
   {
@@ -889,7 +889,8 @@ bool mysql_truncate(THD *thd, TABLE_LIST *table_list, bool dont_send_ok)
       DBUG_RETURN(TRUE);
   }
 
-  *fn_ext(path)=0;				// Remove the .frm extension
+  // Remove the .frm extension
+  *(path + path_length - reg_ext_length)= '\0';
   error= ha_create_table(thd, path, table_list->db, table_list->table_name,
                          &create_info, 1);
   query_cache_invalidate3(thd, table_list, 0);
diff --git a/sql/sql_rename.cc b/sql/sql_rename.cc
index a1bbb69bc17..150c1dba1c9 100644
--- a/sql/sql_rename.cc
+++ b/sql/sql_rename.cc
@@ -155,18 +155,15 @@ rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
       old_alias= ren_table->table_name;
       new_alias= new_table->table_name;
     }
-    sprintf(name,"%s/%s/%s%s",mysql_data_home,
-	    new_table->db, new_alias, reg_ext);
-    unpack_filename(name, name);
+    build_table_filename(name, sizeof(name),
+                         new_table->db, new_alias, reg_ext);
     if (!access(name,F_OK))
     {
       my_error(ER_TABLE_EXISTS_ERROR, MYF(0), new_alias);
       DBUG_RETURN(ren_table);			// This can't be skipped
     }
-    sprintf(name,"%s/%s/%s%s",mysql_data_home,
-	    ren_table->db, old_alias,
-	    reg_ext);
-    unpack_filename(name, name);
+    build_table_filename(name, sizeof(name),
+                         ren_table->db, old_alias, reg_ext);
 
     frm_type= mysql_frm_type(thd, name, &table_type);
     switch (frm_type)
diff --git a/sql/sql_show.cc b/sql/sql_show.cc
index b7f7f1b9487..16a783a2ad0 100644
--- a/sql/sql_show.cc
+++ b/sql/sql_show.cc
@@ -413,9 +413,14 @@ mysql_find_files(THD *thd,List<char> *files, const char *db,const char *path,
 
   for (i=0 ; i < (uint) dirp->number_off_files  ; i++)
   {
+    char uname[NAME_LEN*3+1];                   /* Unencoded name */
     file=dirp->dir_entry+i;
     if (dir)
     {                                           /* Return databases */
+      if ((file->name[0] == '.' && 
+          ((file->name[1] == '.' && file->name[2] == '\0') ||
+            file->name[1] == '\0')))
+        continue;                               /* . or .. */
 #ifdef USE_SYMDIR
       char *ext;
       char buff[FN_REFLEN];
@@ -432,17 +437,21 @@ mysql_find_files(THD *thd,List<char> *files, const char *db,const char *path,
                continue;
        }
 #endif
-        if (file->name[0] == '.' || !MY_S_ISDIR(file->mystat->st_mode) ||
-            (wild && wild_compare(file->name,wild,0)))
-          continue;
+      VOID(filename_to_tablename(file->name, uname, sizeof(uname)));
+      if (!MY_S_ISDIR(file->mystat->st_mode) ||
+          (wild && wild_compare(uname, wild, 0)))
+        continue;
+      file->name= uname;
     }
     else
     {
         // Return only .frm files which aren't temp files.
-      if (my_strcasecmp(system_charset_info, ext=fn_ext(file->name),reg_ext) ||
+      if (my_strcasecmp(system_charset_info, ext=fn_rext(file->name),reg_ext) ||
           is_prefix(file->name,tmp_file_prefix))
         continue;
       *ext=0;
+      VOID(filename_to_tablename(file->name, uname, sizeof(uname)));
+      file->name= uname;
       if (wild)
       {
 	if (lower_case_table_names)
@@ -604,8 +613,7 @@ bool mysqld_show_create_db(THD *thd, char *dbname,
   }
   else
   {
-    (void) sprintf(path,"%s/%s",mysql_data_home, dbname);
-    length=unpack_dirname(path,path);		// Convert if not unix
+    length= build_table_filename(path, sizeof(path), dbname, "", "");
     found_libchar= 0;
     if (length && path[length-1] == FN_LIBCHAR)
     {
@@ -883,7 +891,7 @@ store_create_info(THD *thd, TABLE_LIST *table_list, String *packet,
                   HA_CREATE_INFO *create_info_arg)
 {
   List<Item> field_list;
-  char tmp[MAX_FIELD_WIDTH], *for_str, buff[128], *end;
+  char tmp[MAX_FIELD_WIDTH], *for_str, buff[128], *end, uname[NAME_LEN*3+1];
   const char *alias;
   String type(tmp, sizeof(tmp), system_charset_info);
   Field **ptr,*field;
@@ -914,8 +922,14 @@ store_create_info(THD *thd, TABLE_LIST *table_list, String *packet,
   if (table_list->schema_table)
     alias= table_list->schema_table->table_name;
   else
-    alias= (lower_case_table_names == 2 ? table->alias :
-            share->table_name.str);
+  {
+    if (lower_case_table_names == 2)
+      alias= table->alias;
+    else
+    {
+      alias= share->table_name.str;
+    }
+  }
   append_identifier(thd, packet, alias, strlen(alias));
   packet->append(STRING_WITH_LEN(" (\n"));
 
@@ -2312,8 +2326,8 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
       }
       else
       {
-        strxmov(path, mysql_data_home, "/", base_name, NullS);
-        end= path + (len= unpack_dirname(path,path));
+        len= build_table_filename(path, sizeof(path), base_name, "", "");
+        end= path + len;
         len= FN_LEN - len;
         if (mysql_find_files(thd, &files, base_name, 
                              path, idx_field_vals.table_value, 0))
@@ -2460,8 +2474,7 @@ int fill_schema_shemata(THD *thd, TABLE_LIST *tables, COND *cond)
 	(grant_option && !check_grant_db(thd, file_name)))
 #endif
     {
-      strxmov(path, mysql_data_home, "/", file_name, NullS);
-      length=unpack_dirname(path,path);		// Convert if not unix
+      length= build_table_filename(path, sizeof(path), file_name, "", "");
       found_libchar= 0;
       if (length && path[length-1] == FN_LIBCHAR)
       {
diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index be30e487f28..5a083fcdd22 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -103,28 +103,53 @@ static bool abort_and_upgrade_lock(THD *thd, TABLE *table, const char *db,
 }
 
 /*
- Build the path to a file for a table (or the base path that can
- then have various extensions stuck on to it).
+  Creates path to a file: mysql_data_dir/db/table.ext
 
   SYNOPSIS
-   build_table_path()
-   buff                 Buffer to build the path into
-   bufflen              sizeof(buff)
-   db                   Name of database
-   table                Name of table
-   ext                  Filename extension
+   build_table_filename()
+   buff			where to write result
+   bufflen              buff size
+   db                   database name, in system_charset_info
+   table                table name, in system_charset_info
+   ext                  file extension
+
+  NOTES
+
+    Uses database and table name, and extension to create
+    a file name in mysql_data_dir. Database and table
+    names are converted from system_charset_info into "fscs".
+    'ext' is not converted.
 
   RETURN
-    0                   Error
-    #                   Size of path
- */
 
-static uint build_table_path(char *buff, size_t bufflen, const char *db,
+*/
+
+
+uint build_table_filename(char *buff, size_t bufflen, const char *db,
+                          const char *table, const char *ext)
+{
+  uint length;
+  char dbbuff[FN_REFLEN];
+  char tbbuff[FN_REFLEN];
+  VOID(tablename_to_filename(table, tbbuff, sizeof(tbbuff)));
+  VOID(tablename_to_filename(db, dbbuff, sizeof(dbbuff)));
+  strxnmov(buff, bufflen,
+           mysql_data_home, "/", dbbuff, "/", tbbuff, ext, NullS);
+  length= unpack_filename(buff, buff);
+  return length;
+}
+
+
+uint build_tmptable_filename(char *buff, size_t bufflen,
+                             const char *tmpdir,
                              const char *table, const char *ext)
 {
-  strxnmov(buff, bufflen-1, mysql_data_home, "/", db, "/", table, ext,
-           NullS);
-  return unpack_filename(buff,buff);
+  uint length;
+  char tbbuff[FN_REFLEN];
+  VOID(tablename_to_filename(table, tbbuff, sizeof(tbbuff)));
+  strxnmov(buff, bufflen, tmpdir, "/", tbbuff, ext, NullS);
+  length= unpack_filename(buff, buff);
+  return length;
 }
 
 
@@ -276,7 +301,8 @@ int mysql_rm_table_part2(THD *thd, TABLE_LIST *tables, bool if_exists,
 			 bool dont_log_query)
 {
   TABLE_LIST *table;
-  char	path[FN_REFLEN], *alias;
+  char path[FN_REFLEN], *alias;
+  uint path_length;
   String wrong_tables;
   int error;
   int non_temp_tables_count= 0;
@@ -365,7 +391,8 @@ int mysql_rm_table_part2(THD *thd, TABLE_LIST *tables, bool if_exists,
       }
       alias= (lower_case_table_names == 2) ? table->alias : table->table_name;
       /* remove .frm file and engine files */
-      build_table_path(path, sizeof(path), db, alias, reg_ext);
+      path_length= build_table_filename(path, sizeof(path),
+                                        db, alias, reg_ext);
     }
     if (table_type == NULL &&
         (drop_temporary ||
@@ -390,7 +417,8 @@ int mysql_rm_table_part2(THD *thd, TABLE_LIST *tables, bool if_exists,
 	mysql_frm_type(thd, path, &frm_db_type);
         table_type= ha_resolve_by_legacy_type(thd, frm_db_type);
       }
-      *(end=fn_ext(path))=0;			// Remove extension for delete
+      // Remove extension for delete
+      *(end= path + path_length - reg_ext_length)= '\0';
       error= ha_delete_table(thd, table_type, path, db, table->table_name,
                              !dont_log_query);
       if ((error == ENOENT || error == HA_ERR_NO_SUCH_TABLE) && 
@@ -495,10 +523,11 @@ bool quick_rm_table(handlerton *base,const char *db,
   bool error= 0;
   DBUG_ENTER("quick_rm_table");
 
-  build_table_path(path, sizeof(path), db, table_name, reg_ext);
+  uint path_length= build_table_filename(path, sizeof(path),
+                                         db, table_name, reg_ext);
   if (my_delete(path,MYF(0)))
     error= 1; /* purecov: inspected */
-  *fn_ext(path)= 0;                             // Remove reg_ext
+  path[path_length - reg_ext_length]= '\0'; // Remove reg_ext
   DBUG_RETURN(ha_delete_table(current_thd, base, path, db, table_name, 0) ||
               error);
 }
@@ -1562,8 +1591,8 @@ static void set_table_default_charset(THD *thd,
   {
     HA_CREATE_INFO db_info;
     char path[FN_REFLEN];
-    /* Abuse build_table_path() to build the path to the db.opt file */
-    build_table_path(path, sizeof(path), db, MY_DB_OPT_FILE, "");
+    /* Abuse build_table_filename() to build the path to the db.opt file */
+    build_table_filename(path, sizeof(path), db, "", MY_DB_OPT_FILE);
     load_db_opt(thd, path, &db_info);
     create_info->default_table_charset= db_info.default_table_charset;
   }
@@ -1707,6 +1736,7 @@ bool mysql_create_table(THD *thd,const char *db, const char *table_name,
                         uint select_field_count)
 {
   char		path[FN_REFLEN];
+  uint          path_length;
   const char	*alias;
   uint		db_options, key_count;
   KEY		*key_info_buffer;
@@ -1822,15 +1852,18 @@ bool mysql_create_table(THD *thd,const char *db, const char *table_name,
       /* Check if table exists */
   if (create_info->options & HA_LEX_CREATE_TMP_TABLE)
   {
-    my_snprintf(path, sizeof(path), "%s%s%lx_%lx_%x%s",
-		mysql_tmpdir, tmp_file_prefix, current_pid, thd->thread_id,
-		thd->tmp_table++, reg_ext);
+    char tmp_table_name[tmp_file_prefix_length+22+22+22+3];
+    my_snprintf(tmp_table_name, sizeof(tmp_table_name), "%s%lx_%lx_%x",
+		tmp_file_prefix, current_pid, thd->thread_id,
+		thd->tmp_table++);
+    path_length= build_tmptable_filename(path, sizeof(path), mysql_tmpdir,
+                                         tmp_table_name, reg_ext);
     if (lower_case_table_names)
       my_casedn_str(files_charset_info, path);
     create_info->table_options|=HA_CREATE_DELAY_KEY_WRITE;
   }
   else
-    build_table_path(path, sizeof(path), db, alias, reg_ext);
+    path_length= build_table_filename(path, sizeof(path), db, alias, reg_ext);
 
   /* Check if table already exists */
   if ((create_info->options & HA_LEX_CREATE_TMP_TABLE) &&
@@ -1894,6 +1927,7 @@ bool mysql_create_table(THD *thd,const char *db, const char *table_name,
     create_info->data_file_name= create_info->index_file_name= 0;
   create_info->table_options=db_options;
 
+  path[path_length - reg_ext_length]= '\0'; // Remove .frm extension
   if (rea_create_table(thd, path, db, table_name, create_info, fields,
                        key_count, key_info_buffer, file))
     goto unlock_and_end;
@@ -1901,7 +1935,6 @@ bool mysql_create_table(THD *thd,const char *db, const char *table_name,
   if (create_info->options & HA_LEX_CREATE_TMP_TABLE)
   {
     /* Open table and put in temporary table list */
-    *fn_ext(path)= 0;
     if (!(open_temporary_table(thd, path, db, table_name, 1)))
     {
       (void) rm_temporary_table(create_info->db_type, path);
@@ -2105,8 +2138,8 @@ mysql_rename_table(handlerton *base,
   file= (base == NULL ? 0 :
          get_new_handler((TABLE_SHARE*) 0, thd->mem_root, base));
 
-  build_table_path(from, sizeof(from), old_db, old_name, "");
-  build_table_path(to, sizeof(to), new_db, new_name, "");
+  build_table_filename(from, sizeof(from), old_db, old_name, "");
+  build_table_filename(to, sizeof(to), new_db, new_name, "");
 
   /*
     If lower_case_table_names == 2 (case-preserving but case-insensitive
@@ -2118,12 +2151,12 @@ mysql_rename_table(handlerton *base,
   {
     strmov(tmp_name, old_name);
     my_casedn_str(files_charset_info, tmp_name);
-    build_table_path(lc_from, sizeof(lc_from), old_db, tmp_name, "");
+    build_table_filename(lc_from, sizeof(lc_from), old_db, tmp_name, "");
     from_base= lc_from;
 
     strmov(tmp_name, new_name);
     my_casedn_str(files_charset_info, tmp_name);
-    build_table_path(lc_to, sizeof(lc_to), new_db, tmp_name, "");
+    build_table_filename(lc_to, sizeof(lc_to), new_db, tmp_name, "");
     to_base= lc_to;
   }
 
@@ -2248,23 +2281,21 @@ static int prepare_for_restore(THD* thd, TABLE_LIST* table,
   else
   {
     char* backup_dir= thd->lex->backup_dir;
-    char src_path[FN_REFLEN], dst_path[FN_REFLEN];
+    char src_path[FN_REFLEN], dst_path[FN_REFLEN], uname[FN_REFLEN];
     char* table_name= table->table_name;
     char* db= table->db;
 
-    if (fn_format_relative_to_data_home(src_path, table_name, backup_dir,
-					reg_ext))
+    VOID(tablename_to_filename(table->table_name, uname, sizeof(uname)));
+
+    if (fn_format_relative_to_data_home(src_path, uname, backup_dir, reg_ext))
       DBUG_RETURN(-1); // protect buffer overflow
 
-    my_snprintf(dst_path, sizeof(dst_path), "%s%s/%s",
-		mysql_real_data_home, db, table_name);
+    build_table_filename(dst_path, sizeof(dst_path), db, table_name, reg_ext);
 
     if (lock_and_wait_for_table_name(thd,table))
       DBUG_RETURN(-1);
 
-    if (my_copy(src_path,
-		fn_format(dst_path, dst_path,"", reg_ext, 4),
-		MYF(MY_WME)))
+    if (my_copy(src_path, dst_path, MYF(MY_WME)))
     {
       pthread_mutex_lock(&LOCK_open);
       unlock_table_name(thd, table);
@@ -2937,6 +2968,7 @@ bool mysql_create_like_table(THD* thd, TABLE_LIST* table,
 {
   TABLE *tmp_table;
   char src_path[FN_REFLEN], dst_path[FN_REFLEN];
+  uint dst_path_length;
   char *db= table->db;
   char *table_name= table->table_name;
   char *src_db;
@@ -2976,8 +3008,8 @@ bool mysql_create_like_table(THD* thd, TABLE_LIST* table,
     strxmov(src_path, tmp_table->s->path.str, reg_ext, NullS);
   else
   {
-    strxmov(src_path, mysql_data_home, "/", src_db, "/", src_table,
-	    reg_ext, NullS);
+    build_table_filename(src_path, sizeof(src_path),
+                         src_db, src_table, reg_ext);
     /* Resolve symlinks (for windows) */
     unpack_filename(src_path, src_path);
     if (lower_case_table_names)
@@ -3008,18 +3040,18 @@ bool mysql_create_like_table(THD* thd, TABLE_LIST* table,
   {
     if (find_temporary_table(thd, db, table_name))
       goto table_exists;
-    my_snprintf(dst_path, sizeof(dst_path), "%s%s%lx_%lx_%x%s",
-		mysql_tmpdir, tmp_file_prefix, current_pid,
-		thd->thread_id, thd->tmp_table++, reg_ext);
+    dst_path_length= my_snprintf(dst_path, sizeof(dst_path),
+                                 "%s%s%lx_%lx_%x%s",
+                                 mysql_tmpdir, tmp_file_prefix, current_pid,
+                                 thd->thread_id, thd->tmp_table++, reg_ext);
     if (lower_case_table_names)
       my_casedn_str(files_charset_info, dst_path);
     create_info->table_options|= HA_CREATE_DELAY_KEY_WRITE;
   }
   else
   {
-    strxmov(dst_path, mysql_data_home, "/", db, "/", table_name,
-	    reg_ext, NullS);
-    unpack_filename(dst_path, dst_path);
+    dst_path_length= build_table_filename(dst_path, sizeof(dst_path),
+                                          db, table_name, reg_ext);
     if (!access(dst_path, F_OK))
       goto table_exists;
   }
@@ -3041,7 +3073,7 @@ bool mysql_create_like_table(THD* thd, TABLE_LIST* table,
     creation, instead create the table directly (for both normal
     and temporary tables).
   */
-  *fn_ext(dst_path)= 0;                         // Remove .frm
+  dst_path[dst_path_length - reg_ext_length]= '\0';  // Remove .frm
   err= ha_create_table(thd, dst_path, db, table_name, create_info, 1);
 
   if (create_info->options & HA_LEX_CREATE_TMP_TABLE)
@@ -3324,10 +3356,10 @@ int mysql_create_indexes(THD *thd, TABLE_LIST *table_list, List<Key> &keys)
   else
   {
     if (table->file->add_index(table, key_info_buffer, key_count)||
-        build_table_path(path, sizeof(path), table_list->db,
-                         (lower_case_table_names == 2) ?
-                         table_list->alias : table_list->table_name,
-                         reg_ext) == 0 ||
+        build_table_filename(path, sizeof(path), table_list->db,
+                             (lower_case_table_names == 2) ?
+                             table_list->alias : table_list->table_name,
+                             reg_ext) == 0 ||
 	mysql_create_frm(thd, path, &create_info,
 			 fields, key_count, key_info_buffer, table->file))
       /* don't need to free((gptr) key_info_buffer);*/
@@ -3425,10 +3457,10 @@ int mysql_drop_indexes(THD *thd, TABLE_LIST *table_list,
 			    &keys, /*tmp_table*/ 0, &db_options, table->file,
 			    &key_info_buffer, key_count,
 			    /*select_field_count*/ 0)||
-        build_table_path(path, sizeof(path), table_list->db,
-                         (lower_case_table_names == 2) ?
-                         table_list->alias : table_list->table_name,
-                         reg_ext) == 0 ||
+        build_table_filename(path, sizeof(path), table_list->db,
+                             (lower_case_table_names == 2) ?
+                             table_list->alias : table_list->table_name,
+                             reg_ext) == 0 ||
 	mysql_create_frm(thd, path, &create_info,
 			 fields, key_count, key_info_buffer, table->file))
       /*don't need to free((gptr) key_numbers);*/
@@ -4532,7 +4564,7 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
       */
       uint old_lock_type;
       partition_info *part_info= table->part_info;
-      char path[FN_REFLEN+1];
+      char path[FN_REFLEN+1], noext_path[FN_REFLEN+1];
       uint db_options= 0, key_count, syntax_len;
       KEY *key_info_buffer;
       char *part_syntax_buf;
@@ -4555,7 +4587,7 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
       }
       part_info->part_info_string= part_syntax_buf;
       part_info->part_info_len= syntax_len;
-      build_table_path(path, sizeof(path), db, table_name, reg_ext);
+      build_table_filename(path, sizeof(path), db, table_name, reg_ext);
       if (mysql_create_frm(thd, path, db, table_name, create_info,
                            create_list, key_count, key_info_buffer,
                            table->file))
@@ -4563,7 +4595,7 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
         DBUG_RETURN(TRUE);
       }
       thd->lex->part_info= part_info;
-      build_table_path(path, sizeof(path), db, table_name, "");
+      build_table_filename(path, sizeof(path), db, table_name, "");
       if (table->file->drop_partitions(path))
       {
         DBUG_RETURN(TRUE);
@@ -4591,11 +4623,12 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
       }
       part_info->part_info_string= part_syntax_buf;
       part_info->part_info_len= syntax_len;
-      build_table_path(path, sizeof(path), db, table_name, reg_ext);
+      build_table_filename(path, sizeof(path), db, table_name, reg_ext);
+      build_table_filename(noext_path, sizeof(noext_path), db, table_name, "");
       if (mysql_create_frm(thd, path, db, table_name, create_info,
                            create_list, key_count, key_info_buffer,
                            table->file)  ||
-          table->file->create_handler_files(path))
+          table->file->create_handler_files(noext_path))
       {
         DBUG_RETURN(TRUE);
       }
@@ -4688,9 +4721,7 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
     {
       char path[FN_REFLEN];
       /* table is a normal table: Create temporary table in same directory */
-      strxnmov(path, sizeof(path)-1, mysql_data_home, "/",new_db, "/",
-               tmp_name, NullS);
-      unpack_filename(path, path);
+      build_table_filename(path, sizeof(path), new_db, tmp_name, "");
       new_table=open_temporary_table(thd, path, new_db, tmp_name,0);
     }
     if (!new_table)
@@ -4906,7 +4937,7 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
       shutdown.
     */
     char path[FN_REFLEN];
-    build_table_path(path, sizeof(path), new_db, table_name, "");
+    build_table_filename(path, sizeof(path), new_db, table_name, "");
     table=open_temporary_table(thd, path, new_db, tmp_name,0);
     if (table)
     {
diff --git a/sql/sql_trigger.cc b/sql/sql_trigger.cc
index 7b501364701..2b124fb5bb4 100644
--- a/sql/sql_trigger.cc
+++ b/sql/sql_trigger.cc
@@ -305,9 +305,9 @@ bool Table_triggers_list::create_trigger(THD *thd, TABLE_LIST *tables,
 {
   LEX *lex= thd->lex;
   TABLE *table= tables->table;
-  char dir_buff[FN_REFLEN], file_buff[FN_REFLEN], trigname_buff[FN_REFLEN],
+  char file_buff[FN_REFLEN], trigname_buff[FN_REFLEN],
        trigname_path[FN_REFLEN];
-  LEX_STRING dir, file, trigname_file;
+  LEX_STRING file, trigname_file;
   LEX_STRING *trg_def, *name;
   ulonglong *trg_sql_mode;
   char trg_definer_holder[HOSTNAME_LENGTH + USERNAME_LENGTH + 2];
@@ -386,20 +386,18 @@ bool Table_triggers_list::create_trigger(THD *thd, TABLE_LIST *tables,
     sql_create_definition_file() files handles renaming and backup of older
     versions
   */
-  strxnmov(dir_buff, FN_REFLEN-1, mysql_data_home, "/", tables->db, "/", NullS);
-  dir.length= unpack_filename(dir_buff, dir_buff);
-  dir.str= dir_buff;
-  file.length=  strxnmov(file_buff, FN_REFLEN-1, tables->table_name,
-                         triggers_file_ext, NullS) - file_buff;
+  file.length= build_table_filename(file_buff, FN_REFLEN-1,
+                                    tables->db, tables->table_name,
+                                    triggers_file_ext);
   file.str= file_buff;
-  trigname_file.length= strxnmov(trigname_buff, FN_REFLEN-1,
-                                 lex->spname->m_name.str,
-                                 trigname_file_ext, NullS) - trigname_buff;
+  trigname_file.length= build_table_filename(trigname_buff, FN_REFLEN-1,
+                                             tables->db,
+                                             lex->spname->m_name.str,
+                                             trigname_file_ext);
   trigname_file.str= trigname_buff;
-  strxnmov(trigname_path, FN_REFLEN-1, dir_buff, trigname_buff, NullS);
 
   /* Use the filesystem to enforce trigger namespace constraints. */
-  if (!access(trigname_path, F_OK))
+  if (!access(trigname_buff, F_OK))
   {
     my_error(ER_TRG_ALREADY_EXISTS, MYF(0));
     return 1;
@@ -408,7 +406,7 @@ bool Table_triggers_list::create_trigger(THD *thd, TABLE_LIST *tables,
   trigname.trigger_table.str= tables->table_name;
   trigname.trigger_table.length= tables->table_name_length;
 
-  if (sql_create_definition_file(&dir, &trigname_file, &trigname_file_type,
+  if (sql_create_definition_file(NULL, &trigname_file, &trigname_file_type,
                                  (gptr)&trigname, trigname_file_parameters, 0))
     return 1;
 
@@ -455,7 +453,7 @@ bool Table_triggers_list::create_trigger(THD *thd, TABLE_LIST *tables,
   trg_definer->length= strxmov(trg_definer->str, definer_user->str, "@",
                                definer_host->str, NullS) - trg_definer->str;
 
-  if (!sql_create_definition_file(&dir, &file, &triggers_file_type,
+  if (!sql_create_definition_file(NULL, &file, &triggers_file_type,
                                   (gptr)this, triggers_file_parameters,
                                   TRG_MAX_VERSIONS))
     return 0;
@@ -483,9 +481,7 @@ err_with_cleanup:
 
 static bool rm_trigger_file(char *path, char *db, char *table_name)
 {
-  strxnmov(path, FN_REFLEN-1, mysql_data_home, "/", db, "/", table_name,
-           triggers_file_ext, NullS);
-  unpack_filename(path, path);
+  build_table_filename(path, FN_REFLEN-1, db, table_name, triggers_file_ext);
   return my_delete(path, MYF(MY_WME));
 }
 
@@ -507,9 +503,7 @@ static bool rm_trigger_file(char *path, char *db, char *table_name)
 
 static bool rm_trigname_file(char *path, char *db, char *trigger_name)
 {
-  strxnmov(path, FN_REFLEN-1, mysql_data_home, "/", db, "/", trigger_name,
-           trigname_file_ext, NullS);
-  unpack_filename(path, path);
+  build_table_filename(path, FN_REFLEN-1, db, trigger_name, trigname_file_ext);
   return my_delete(path, MYF(MY_WME));
 }
 
@@ -567,18 +561,14 @@ bool Table_triggers_list::drop_trigger(THD *thd, TABLE_LIST *tables)
       }
       else
       {
-        char dir_buff[FN_REFLEN], file_buff[FN_REFLEN];
-        LEX_STRING dir, file;
-
-        strxnmov(dir_buff, FN_REFLEN-1, mysql_data_home, "/", tables->db,
-                 "/", NullS);
-        dir.length= unpack_filename(dir_buff, dir_buff);
-        dir.str= dir_buff;
-        file.length=  strxnmov(file_buff, FN_REFLEN-1, tables->table_name,
-                               triggers_file_ext, NullS) - file_buff;
-        file.str= file_buff;
+        char file_buff[FN_REFLEN];
+        LEX_STRING file;
 
-        if (sql_create_definition_file(&dir, &file, &triggers_file_type,
+        file.length= build_table_filename(file_buff, FN_REFLEN-1,
+                                          tables->db, tables->table_name,
+                                          triggers_file_ext);
+        file.str= file_buff;
+        if (sql_create_definition_file(NULL, &file, &triggers_file_type,
                                        (gptr)this, triggers_file_parameters,
                                        TRG_MAX_VERSIONS))
           return 1;
@@ -692,9 +682,8 @@ bool Table_triggers_list::check_n_load(THD *thd, const char *db,
 
   DBUG_ENTER("Table_triggers_list::check_n_load");
 
-  strxnmov(path_buff, FN_REFLEN-1, mysql_data_home, "/", db, "/", table_name,
-           triggers_file_ext, NullS);
-  path.length= unpack_filename(path_buff, path_buff);
+  path.length= build_table_filename(path_buff, FN_REFLEN-1,
+                                    db, table_name, triggers_file_ext);
   path.str= path_buff;
 
   // QQ: should we analyze errno somehow ?
@@ -1026,9 +1015,9 @@ static TABLE_LIST *add_table_for_trigger(THD *thd, sp_name *trig)
   struct st_trigname trigname;
   DBUG_ENTER("add_table_for_trigger");
 
-  strxnmov(path_buff, FN_REFLEN-1, mysql_data_home, "/", trig->m_db.str, "/",
-           trig->m_name.str, trigname_file_ext, NullS);
-  path.length= unpack_filename(path_buff, path_buff);
+  path.length= build_table_filename(path_buff, FN_REFLEN-1,
+                                    trig->m_db.str, trig->m_name.str,
+                                    trigname_file_ext);
   path.str= path_buff;
 
   if (access(path_buff, F_OK))
diff --git a/sql/sql_view.cc b/sql/sql_view.cc
index aea07be1eda..78497a2cf8b 100644
--- a/sql/sql_view.cc
+++ b/sql/sql_view.cc
@@ -568,8 +568,8 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
   String str(buff,(uint32) sizeof(buff), system_charset_info);
   char md5[MD5_BUFF_LENGTH];
   bool can_be_merged;
-  char dir_buff[FN_REFLEN], file_buff[FN_REFLEN];
-  LEX_STRING dir, file;
+  char dir_buff[FN_REFLEN], file_buff[FN_REFLEN], path_buff[FN_REFLEN];
+  LEX_STRING dir, file, path;
   DBUG_ENTER("mysql_register_view");
 
   /* print query */
@@ -584,15 +584,17 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
   DBUG_PRINT("info", ("View: %s", str.ptr()));
 
   /* print file name */
-  (void) my_snprintf(dir_buff, FN_REFLEN, "%s/%s/",
-		     mysql_data_home, view->db);
-  unpack_filename(dir_buff, dir_buff);
+  dir.length= build_table_filename(dir_buff, sizeof(dir_buff),
+                                   view->db, "", "");
   dir.str= dir_buff;
-  dir.length= strlen(dir_buff);
 
-  file.str= file_buff;
-  file.length= (strxnmov(file_buff, FN_REFLEN-1, view->table_name, reg_ext,
-                         NullS) - file_buff);
+  path.length= build_table_filename(path_buff, sizeof(path_buff),
+                                    view->db, view->table_name, reg_ext);
+  path.str= path_buff;
+
+  file.str= path.str + dir.length;
+  file.length= path.length - dir.length;
+
   /* init timestamp */
   if (!view->timestamp.str)
     view->timestamp.str= view->timestamp_buffer;
@@ -1184,9 +1186,8 @@ bool mysql_drop_view(THD *thd, TABLE_LIST *views, enum_drop_mode drop_mode)
   {
     TABLE_SHARE *share;
     bool type= 0;
-    strxnmov(path, FN_REFLEN-1, mysql_data_home, "/", view->db, "/",
-             view->table_name, reg_ext, NullS);
-    (void) unpack_filename(path, path);
+    build_table_filename(path, sizeof(path),
+                         view->db, view->table_name, reg_ext);
     VOID(pthread_mutex_lock(&LOCK_open));
     if (access(path, F_OK) ||
 	(type= (mysql_frm_type(thd, path, &not_used) != FRMTYPE_VIEW)))
diff --git a/sql/strfunc.cc b/sql/strfunc.cc
index c822d10af46..4eb20faa97c 100644
--- a/sql/strfunc.cc
+++ b/sql/strfunc.cc
@@ -235,3 +235,79 @@ uint check_word(TYPELIB *lib, const char *val, const char *end,
     *end_of_word= ptr;
   return res;
 }
+
+
+/*
+  Converts a string between character sets
+
+  SYNOPSIS
+    strconvert()
+    from_cs       source character set
+    from          source, a null terminated string
+    to            destination buffer
+    to_length     destination buffer length
+
+  NOTES
+    'to' is always terminated with a '\0' character.
+    If there is no enough space to convert whole string,
+    only prefix is converted, and terminated with '\0'.
+
+  RETURN VALUES
+    result string length
+*/
+
+
+uint strconvert(CHARSET_INFO *from_cs, const char *from,
+                CHARSET_INFO *to_cs, char *to, uint to_length)
+{
+  int cnvres;
+  my_wc_t wc;
+  char *to_start= to;
+  uchar *to_end= (uchar*) to + to_length - 1;
+  int (*mb_wc)(struct charset_info_st *, my_wc_t *, const uchar *,
+	       const uchar *)= from_cs->cset->mb_wc;
+  int (*wc_mb)(struct charset_info_st *, my_wc_t, uchar *s, uchar *e)=
+    to_cs->cset->wc_mb;
+  uint error_count= 0;
+
+  while (1)
+  {
+    /*
+      Using 'from + 10' is safe:
+      - it is enough to scan a single character in any character set.
+      - if remaining string is shorter than 10, then mb_wc will return
+        with error because of unexpected '\0' character.
+    */
+    if ((cnvres= (*mb_wc)(from_cs, &wc,
+                          (uchar*) from, (uchar*) from + 10)) > 0)
+    {
+      if (!wc)
+        break;
+      from+= cnvres;
+    }
+    else if (cnvres == MY_CS_ILSEQ)
+    {
+      error_count++;
+      from++;
+      wc= '?';
+    }
+    else
+      break; // Impossible char.
+
+outp:
+
+    if ((cnvres= (*wc_mb)(to_cs, wc, (uchar*) to, to_end)) > 0)
+      to+= cnvres;
+    else if (cnvres == MY_CS_ILUNI && wc != '?')
+    {
+      error_count++;
+      wc= '?';
+      goto outp;
+    }
+    else
+      break;
+  }
+  *to= '\0';
+  return (uint32) (to - to_start);
+
+}
diff --git a/sql/table.cc b/sql/table.cc
index bf208918346..02d56eb01e8 100644
--- a/sql/table.cc
+++ b/sql/table.cc
@@ -43,6 +43,37 @@ static byte *get_field_name(Field **buff, uint *length,
 }
 
 
+
+/*
+  Returns pointer to '.frm' extension of the file name.
+
+  SYNOPSIS
+    fn_rext()
+    name       file name
+
+  DESCRIPTION
+    Checks file name part starting with the rightmost '.' character,
+    and returns it if it is equal to '.frm'. 
+
+  TODO
+    It is a good idea to get rid of this function modifying the code
+    to garantee that the functions presently calling fn_rext() always
+    get arguments in the same format: either with '.frm' or without '.frm'.
+
+  RETURN VALUES
+    Pointer to the '.frm' extension. If there is no extension,
+    or extension is not '.frm', pointer at the end of file name.
+*/
+
+char *fn_rext(char *name)
+{
+  char *res= strrchr(name, '.');
+  if (res && !strcmp(res, ".frm"))
+    return res;
+  return name + strlen(name);
+}
+
+
 /*
   Allocate a setup TABLE_SHARE structure
 
@@ -65,9 +96,13 @@ TABLE_SHARE *alloc_table_share(TABLE_LIST *table_list, char *key,
   char path[FN_REFLEN], normalized_path[FN_REFLEN];
   uint path_length, normalized_length;
 
-  path_length= (uint) (strxmov(path, mysql_data_home, "/", table_list->db,
-                               "/", table_list->table_name, NullS) - path);
-  normalized_length= unpack_filename(normalized_path, path);
+  path_length= build_table_filename(path, sizeof(path) - 1,
+                                    table_list->db,
+                                    table_list->table_name, "");
+  normalized_length= build_table_filename(normalized_path,
+                                          sizeof(normalized_path) - 1,
+                                          table_list->db,
+                                          table_list->table_name, "");
 
   init_sql_alloc(&mem_root, TABLE_ALLOC_BLOCK_SIZE, 0);
   if ((share= (TABLE_SHARE*) alloc_root(&mem_root,
@@ -1883,6 +1918,7 @@ void append_unescaped(String *res, const char *pos, uint length)
   res->append('\'');
 }
 
+
 	/* Create a .frm file */
 
 File create_frm(THD *thd, const char *name, const char *db,
@@ -2103,9 +2139,6 @@ bool check_db_name(char *name)
 #else
     last_char_is_space= *name==' ';
 #endif
-    if (*name == '/' || *name == '\\' || *name == FN_LIBCHAR ||
-	*name == FN_EXTCHAR)
-      return 1;
     name++;
   }
   return last_char_is_space || (uint) (name - start) > NAME_LEN;
@@ -2114,8 +2147,7 @@ bool check_db_name(char *name)
 
 /*
   Allow anything as a table name, as long as it doesn't contain an
-  a '/', or a '.' character
-  or ' ' at the end
+  ' ' at the end
   returns 1 on error
 */
 
@@ -2146,8 +2178,6 @@ bool check_table_name(const char *name, uint length)
       }
     }
 #endif
-    if (*name == '/' || *name == '\\' || *name == FN_EXTCHAR)
-      return 1;
     name++;
   }
 #if defined(USE_MB) && defined(USE_MB_IDENT)
diff --git a/sql/unireg.cc b/sql/unireg.cc
index 66be20736e8..7b15e14bdaf 100644
--- a/sql/unireg.cc
+++ b/sql/unireg.cc
@@ -93,6 +93,7 @@ bool mysql_create_frm(THD *thd, const char *file_name,
   thd->lex->part_info= NULL;
 #endif
 
+  DBUG_ASSERT(*fn_rext((char*)file_name)); // Check .frm extension
   formnames.type_names=0;
   if (!(screen_buff=pack_screens(create_fields,&info_length,&screens,0)))
     DBUG_RETURN(1);
@@ -289,7 +290,7 @@ err3:
   SYNOPSIS
     rea_create_table()
     thd			Thread handler
-    path		Name of file (including database and .frm)
+    path		Name of file (including database, without .frm)
     db			Data base name
     table_name		Table name
     create_info		create info parameters
@@ -309,25 +310,26 @@ int rea_create_table(THD *thd, const char *path,
                      List<create_field> &create_fields,
                      uint keys, KEY *key_info, handler *file)
 {
-  char *ext;
   DBUG_ENTER("rea_create_table");
 
-  if (mysql_create_frm(thd, path, db, table_name, create_info,
+  char frm_name[FN_REFLEN];
+  strxmov(frm_name, path, reg_ext, NullS);
+  if (mysql_create_frm(thd, frm_name, db, table_name, create_info,
                        create_fields, keys, key_info, file))
+
     DBUG_RETURN(1);
+
+  // Make sure mysql_create_frm din't remove extension
+  DBUG_ASSERT(*fn_rext(frm_name));
   if (file->create_handler_files(path))
     goto err_handler;
-  *(ext= fn_ext(path))= 0;                             // Remove .frm
   if (!create_info->frm_only && ha_create_table(thd, path, db, table_name,
                                                 create_info,0))
-  {
-    *ext= FN_EXTCHAR;                           // Add extension back
     goto err_handler;
-  }
   DBUG_RETURN(0);
 
 err_handler:
-  my_delete(path, MYF(0));
+  my_delete(frm_name, MYF(0));
   DBUG_RETURN(1);
 } /* rea_create_table */