BUG#2304 - HANDLER and tables in non-current db

mysql-test/r/handler.result

@@ -173,3 +173,21 @@ Unknown column 'W' in 'field list'
 handler t1 read a=(a);
 Wrong arguments to HANDLER ... READ
 drop table t1;
+create table t1 (a char(5));
+insert into t1 values ("Ok");
+handler t1 open as t;
+handler t read first;
+a
+Ok
+use mysql;
+handler t read first;
+a
+Ok
+handler t close;
+handler test.t1 open as t;
+handler t read first;
+a
+Ok
+handler t close;
+use test;
+drop table t1;

mysql-test/t/handler.test

@@ -107,3 +107,19 @@ handler t1 read a=(W);
 handler t1 read a=(a);
 drop table t1;
 
+#
+# BUG#2304
+#
+create table t1 (a char(5));
+insert into t1 values ("Ok");
+handler t1 open as t;
+handler t read first;
+use mysql;
+handler t read first;
+handler t close;
+handler test.t1 open as t;
+handler t read first;
+handler t close;
+use test;
+drop table t1;
+

sql/sql_handler.cc

@@ -276,14 +276,13 @@ static TABLE **find_table_ptr_by_name(THD *thd, const char *db,
   int dblen;
   TABLE **ptr;
 
-  if (!db || ! *db)
-    db= thd->db ? thd->db : "";
-  dblen=strlen(db)+1;
+  DBUG_ASSERT(db);
+  dblen=*db ? strlen(db)+1 : 0;
   ptr=&(thd->handler_tables);
 
   for (TABLE *table=*ptr; table ; table=*ptr)
   {
-    if (!memcmp(table->table_cache_key, db, dblen) &&
+    if ((!dblen || !memcmp(table->table_cache_key, db, dblen)) &&
         !my_strcasecmp((is_alias ? table->table_name : table->real_name),table_name))
     {
       if (table->version != refresh_version)

sql/sql_yacc.yy

@@ -501,7 +501,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 	opt_table_alias
 
 %type <table>
-	table_ident
+	table_ident table_ident_ref
 
 %type <simple_string>
 	remember_name remember_end opt_len opt_ident opt_db text_or_password
@@ -3243,8 +3243,13 @@ field_ident:
 table_ident:
 	ident			{ $$=new Table_ident($1); }
 	| ident '.' ident	{ $$=new Table_ident($1,$3,0);}
-	| '.' ident		{ $$=new Table_ident($2);}
-   /* For Delphi */;
+	| '.' ident		{ $$=new Table_ident($2);} /* For Delphi */
+        ;
+
+table_ident_ref:
+	ident			{ LEX_STRING db={"",0}; $$=new Table_ident(db,$1,0); }
+	| ident '.' ident	{ $$=new Table_ident($1,$3,0);}
+        ;
 
 ident:
 	IDENT	    { $$=$1; }
@@ -3610,13 +3615,13 @@ handler:
 	  if (!add_table_to_list($2,$4,0))
 	    YYABORT;
 	}
-	| HANDLER_SYM table_ident CLOSE_SYM
+	| HANDLER_SYM table_ident_ref CLOSE_SYM
 	{
 	  Lex->sql_command = SQLCOM_HA_CLOSE;
 	  if (!add_table_to_list($2,0,0))
 	    YYABORT;
 	}
-	| HANDLER_SYM table_ident READ_SYM
+	| HANDLER_SYM table_ident_ref READ_SYM
 	{
 	  LEX *lex=Lex;
 	  lex->sql_command = SQLCOM_HA_READ;