Changes in get_table_type() and mysql_frm_type(). The main problem was

that in mysql_rm_table_part2_with_lock() previously we needed to open
same file twice. Now once is enough.

sql/mysql_priv.h

@@ -1295,7 +1295,6 @@ int openfrm(THD *thd, const char *name,const char *alias,uint filestat,
 int readfrm(const char *name, const void** data, uint* length);
 int writefrm(const char* name, const void* data, uint len);
 int closefrm(TABLE *table);
-db_type get_table_type(THD *thd, const char *name);
 int read_string(File file, gptr *to, uint length);
 void free_blobs(TABLE *table);
 int set_zone(int nr,int min_zone,int max_zone);

sql/sql_base.cc

@@ -1193,10 +1193,11 @@ TABLE *open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
     */
     {
       char path[FN_REFLEN];
+      db_type not_used;
       strxnmov(path, FN_REFLEN, mysql_data_home, "/", table_list->db, "/",
                table_list->table_name, reg_ext, NullS);
       (void) unpack_filename(path, path);
-      if (mysql_frm_type(path) == FRMTYPE_VIEW)
+      if (mysql_frm_type(thd, path, &not_used) == FRMTYPE_VIEW)
       {
         TABLE tab;// will not be used (because it's VIEW) but have to be passed
         table= &tab;

sql/sql_delete.cc

@@ -830,7 +830,8 @@ bool mysql_truncate(THD *thd, TABLE_LIST *table_list, bool dont_send_ok)
   if (!dont_send_ok)
   {
     db_type table_type;
-    if ((table_type=get_table_type(thd, path)) == DB_TYPE_UNKNOWN)
+    mysql_frm_type(thd, path, &table_type);
+    if (table_type == DB_TYPE_UNKNOWN)
     {
       my_error(ER_NO_SUCH_TABLE, MYF(0),
                table_list->db, table_list->table_name);

sql/sql_rename.cc

@@ -134,6 +134,8 @@ rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
 {
   TABLE_LIST *ren_table,*new_table;
   frm_type_enum frm_type;
+  db_type table_type;
+
   DBUG_ENTER("rename_tables");
 
   for (ren_table= table_list; ren_table; ren_table= new_table->next_local)
@@ -166,13 +168,12 @@ rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
 	    reg_ext);
     unpack_filename(name, name);
 
-    frm_type= mysql_frm_type(name);
+    frm_type= mysql_frm_type(thd, name, &table_type);
     switch (frm_type)
     {
       case FRMTYPE_TABLE:
       {
-        db_type table_type;
-        if ((table_type= get_table_type(thd, name)) == DB_TYPE_UNKNOWN) 
+        if (table_type == DB_TYPE_UNKNOWN) 
           my_error(ER_FILE_NOT_FOUND, MYF(0), name, my_errno);
         else
           rc= mysql_rename_table(table_type, ren_table->db, old_alias,

sql/sql_show.cc

@@ -2003,6 +2003,7 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
   Security_context *sctx= thd->security_ctx;
   uint derived_tables= lex->derived_tables; 
   int error= 1;
+  db_type not_used;
   Open_tables_state open_tables_state_backup;
   DBUG_ENTER("get_all_tables");
 
@@ -2114,7 +2115,7 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
               else
               {
                 my_snprintf(end, len, "/%s%s", file_name, reg_ext);
-                switch (mysql_frm_type(path)) {
+                switch (mysql_frm_type(thd, path, &not_used)) {
                 case FRMTYPE_ERROR:
                   table->field[3]->store("ERROR", 5, system_charset_info);
                   break;

sql/sql_table.cc

@@ -218,6 +218,7 @@ int mysql_rm_table_part2(THD *thd, TABLE_LIST *tables, bool if_exists,
   String wrong_tables;
   int error;
   bool some_tables_deleted=0, tmp_table_deleted=0, foreign_key_error=0;
+
   DBUG_ENTER("mysql_rm_table_part2");
 
   if (lock_table_names(thd, tables))
@@ -229,6 +230,8 @@ int mysql_rm_table_part2(THD *thd, TABLE_LIST *tables, bool if_exists,
   for (table= tables; table; table= table->next_local)
   {
     char *db=table->db;
+    db_type table_type= DB_TYPE_UNKNOWN;
+
     mysql_ha_flush(thd, table, MYSQL_HA_CLOSE_FINAL);
     if (!close_temporary_table(thd, db, table->table_name))
     {
@@ -256,7 +259,8 @@ int mysql_rm_table_part2(THD *thd, TABLE_LIST *tables, bool if_exists,
     if (drop_temporary ||
        (access(path,F_OK) &&
          ha_create_table_from_engine(thd,db,alias)) ||
-        (!drop_view && mysql_frm_type(path) != FRMTYPE_TABLE))
+        (!drop_view &&
+	 mysql_frm_type(thd, path, &table_type) != FRMTYPE_TABLE))
     {
       // Table was not found on disk and table can't be created from engine
       if (if_exists)
@@ -269,7 +273,8 @@ int mysql_rm_table_part2(THD *thd, TABLE_LIST *tables, bool if_exists,
     else
     {
       char *end;
-      db_type table_type= get_table_type(thd, path);
+      if (table_type == DB_TYPE_UNKNOWN)
+	mysql_frm_type(thd, path, &table_type);
       *(end=fn_ext(path))=0;			// Remove extension for delete
       error= ha_delete_table(thd, table_type, path, table->table_name,
                              !dont_log_query);
@@ -2611,6 +2616,8 @@ bool mysql_create_like_table(THD* thd, TABLE_LIST* table,
   char *src_table= table_ident->table.str;
   int  err;
   bool res= TRUE;
+  db_type not_used;
+
   TABLE_LIST src_tables_list;
   DBUG_ENTER("mysql_create_like_table");
   src_db= table_ident->db.str ? table_ident->db.str : thd->db;
@@ -2658,7 +2665,7 @@ bool mysql_create_like_table(THD* thd, TABLE_LIST* table,
   /* 
      create like should be not allowed for Views, Triggers, ... 
   */
-  if (mysql_frm_type(src_path) != FRMTYPE_TABLE)
+  if (mysql_frm_type(thd, src_path, &not_used) != FRMTYPE_TABLE)
   {
     my_error(ER_WRONG_OBJECT, MYF(0), src_db, src_table, "BASE TABLE");
     goto err;

sql/sql_view.cc

@@ -1110,6 +1110,7 @@ bool mysql_drop_view(THD *thd, TABLE_LIST *views, enum_drop_mode drop_mode)
   char path[FN_REFLEN];
   TABLE_LIST *view;
   bool type= 0;
+  db_type not_used;
 
   for (view= views; view; view= view->next_local)
   {
@@ -1117,7 +1118,8 @@ bool mysql_drop_view(THD *thd, TABLE_LIST *views, enum_drop_mode drop_mode)
              view->table_name, reg_ext, NullS);
     (void) unpack_filename(path, path);
     VOID(pthread_mutex_lock(&LOCK_open));
-    if (access(path, F_OK) || (type= (mysql_frm_type(path) != FRMTYPE_VIEW)))
+    if (access(path, F_OK) ||
+	(type= (mysql_frm_type(thd, path, &not_used) != FRMTYPE_VIEW)))
     {
       char name[FN_REFLEN];
       my_snprintf(name, sizeof(name), "%s.%s", view->db, view->table_name);
@@ -1164,24 +1166,36 @@ bool mysql_drop_view(THD *thd, TABLE_LIST *views, enum_drop_mode drop_mode)
     FRMTYPE_VIEW	view
 */
 
-frm_type_enum mysql_frm_type(char *path)
+frm_type_enum mysql_frm_type(THD *thd, char *path, db_type *dbt)
 {
   File file;
-  char header[10];	//"TYPE=VIEW\n" it is 10 characters
-  int length;
+  uchar header[10];	//"TYPE=VIEW\n" it is 10 characters
+  int error;
   DBUG_ENTER("mysql_frm_type");
 
+  *dbt= DB_TYPE_UNKNOWN;
+
   if ((file= my_open(path, O_RDONLY | O_SHARE, MYF(0))) < 0)
-  {
     DBUG_RETURN(FRMTYPE_ERROR);
-  }
-  length= my_read(file, (byte*) header, sizeof(header), MYF(MY_WME));
+  error= my_read(file, (byte*) header, sizeof(header), MYF(MY_WME | MY_NABP));
   my_close(file, MYF(MY_WME));
-  if (length == (int) MY_FILE_ERROR)
+
+  if (error)
     DBUG_RETURN(FRMTYPE_ERROR);
-  if (length < (int) sizeof(header) ||
-      !strncmp(header, "TYPE=VIEW\n", sizeof(header)))
+  if (!strncmp((char*) header, "TYPE=VIEW\n", sizeof(header)))
     DBUG_RETURN(FRMTYPE_VIEW);
+
+  /*
+    This is just a check for DB_TYPE. We'll return default unknown type
+    if the following test is true (arg #3). This should not have effect
+    on return value from this function (default FRMTYPE_TABLE)
+  */
+  if (header[0] != (uchar) 254 || header[1] != 1 ||
+      (header[2] != FRM_VER && header[2] != FRM_VER+1 &&
+       (header[2] < FRM_VER+3 || header[2] > FRM_VER+4)))
+    DBUG_RETURN(FRMTYPE_TABLE);
+
+  *dbt= ha_checktype(thd, (enum db_type) (uint) *(header + 3), 0, 0);
   DBUG_RETURN(FRMTYPE_TABLE);                   // Is probably a .frm table
 }
 

sql/sql_view.h

@@ -27,7 +27,7 @@ bool check_key_in_view(THD *thd, TABLE_LIST * view);
 
 bool insert_view_fields(THD *thd, List<Item> *list, TABLE_LIST *view);
 
-frm_type_enum mysql_frm_type(char *path);
+frm_type_enum mysql_frm_type(THD *thd, char *path, db_type *dbt);
 
 int view_checksum(THD *thd, TABLE_LIST *view);
 

sql/table.cc

@@ -1692,29 +1692,6 @@ bool check_column_name(const char *name)
   return last_char_is_space || (uint) (name - start) > NAME_LEN;
 }
 
-/*
-** Get type of table from .frm file
-*/
-
-db_type get_table_type(THD *thd, const char *name)
-{
-  File	 file;
-  uchar head[4];
-  int error;
-  DBUG_ENTER("get_table_type");
-  DBUG_PRINT("enter",("name: '%s'",name));
-
-  if ((file=my_open(name,O_RDONLY, MYF(0))) < 0)
-    DBUG_RETURN(DB_TYPE_UNKNOWN);
-  error=my_read(file,(byte*) head,4,MYF(MY_NABP));
-  my_close(file,MYF(0));
-  if (error || head[0] != (uchar) 254 || head[1] != 1 ||
-      (head[2] != FRM_VER && head[2] != FRM_VER+1 &&
-       (head[2] < FRM_VER+3 || head[2] > FRM_VER+4)))
-    DBUG_RETURN(DB_TYPE_UNKNOWN);
-  DBUG_RETURN(ha_checktype(thd,(enum db_type) (uint) *(head+3),0,0));
-}
-
 /*
   Create Item_field for each column in the table.