Don't print warnings about 'setrlimit' if --warnings is not given

Code review/cleanup of sub subselect_uniquesubquery_engine

sql/ha_myisam.cc

@@ -898,7 +898,7 @@ int ha_myisam::index_read(byte * buf, const byte * key,
 			  uint key_len, enum ha_rkey_function find_flag)
 {
   statistic_increment(ha_read_key_count,&LOCK_status);
-  int error=mi_rkey(file,buf,active_index, key, key_len, (enum ha_rkey_function)find_flag);
+  int error=mi_rkey(file,buf,active_index, key, key_len, find_flag);
   table->status=error ? STATUS_NOT_FOUND: 0;
   return error;
 }
@@ -907,7 +907,7 @@ int ha_myisam::index_read_idx(byte * buf, uint index, const byte * key,
 			      uint key_len, enum ha_rkey_function find_flag)
 {
   statistic_increment(ha_read_key_count,&LOCK_status);
-  int error=mi_rkey(file,buf,index, key, key_len, (enum ha_rkey_function)find_flag);
+  int error=mi_rkey(file,buf,index, key, key_len, find_flag);
   table->status=error ? STATUS_NOT_FOUND: 0;
   return error;
 }

sql/item_subselect.cc

@@ -36,7 +36,7 @@ inline Item * and_items(Item* cond, Item *item)
 
 Item_subselect::Item_subselect():
   Item_result_field(), engine_owner(1), value_assigned(0), substitution(0),
-  have_to_be_excluded(0), engine_changed(0)
+  engine(0), have_to_be_excluded(0), engine_changed(0)
 {
   reset();
   /*
@@ -46,6 +46,7 @@ Item_subselect::Item_subselect():
   null_value= 1;
 }
 
+
 void Item_subselect::init(THD *thd, st_select_lex *select_lex,
 			  select_subselect *result)
 {
@@ -62,6 +63,7 @@ void Item_subselect::init(THD *thd, st_select_lex *select_lex,
   DBUG_VOID_RETURN;
 }
 
+
 Item_subselect::~Item_subselect()
 {
   if (engine_owner)
@@ -693,6 +695,7 @@ Item_in_subselect::row_value_transformer(JOIN *join,
   DBUG_RETURN(RES_OK);
 }
 
+
 Item_subselect::trans_res
 Item_in_subselect::select_transformer(JOIN *join)
 {
@@ -702,18 +705,21 @@ Item_in_subselect::select_transformer(JOIN *join)
   return row_value_transformer(join, left_expr);
 }
 
+
 Item_subselect::trans_res
 Item_allany_subselect::select_transformer(JOIN *join)
 {
   return single_value_transformer(join, left_expr, func);
 }
 
-subselect_single_select_engine::subselect_single_select_engine(THD *thd, 
-							       st_select_lex *select,
-							       select_subselect *result,
-							       Item_subselect *item):
-  subselect_engine(thd, item, result),
-    prepared(0), optimized(0), executed(0)
+
+subselect_single_select_engine::
+subselect_single_select_engine(THD *thd, 
+			       st_select_lex *select,
+			       select_subselect *result,
+			       Item_subselect *item)
+  :subselect_engine(thd, item, result),
+   prepared(0), optimized(0), executed(0)
 {
   select_lex= select;
   SELECT_LEX_UNIT *unit= select_lex->master_unit();
@@ -732,11 +738,12 @@ subselect_single_select_engine::subselect_single_select_engine(THD *thd,
   this->select_lex= select_lex;
 }
 
+
 subselect_union_engine::subselect_union_engine(THD *thd,
 					       st_select_lex_unit *u,
 					       select_subselect *result,
-					       Item_subselect *item):
-  subselect_engine(thd, item, result)
+					       Item_subselect *item)
+  :subselect_engine(thd, item, result)
 {
   unit= u;
   if (!result)
@@ -919,6 +926,7 @@ int subselect_union_engine::exec()
   return res;
 }
 
+
 int subselect_uniquesubquery_engine::exec()
 {
   DBUG_ENTER("subselect_uniquesubquery_engine::exec");
@@ -940,34 +948,22 @@ int subselect_uniquesubquery_engine::exec()
     {
       error= 0;
       table->null_row= 0;
-      if (table->status)
-	((Item_in_subselect *) item)->value= 0;
-      else
-	((Item_in_subselect *) item)->value= (!cond || cond->val_int()?1:0);
+      ((Item_in_subselect *) item)->value= (!table->status &&
+					    (!cond || cond->val_int()) ? 1 :
+					    0);
     }
   }
-  DBUG_RETURN(end_exec(table) || (error != 0));
+  DBUG_RETURN(error != 0);
 }
 
-int subselect_uniquesubquery_engine::end_exec(TABLE *table)
+
+subselect_uniquesubquery_engine::~subselect_uniquesubquery_engine()
 {
-  DBUG_ENTER("subselect_uniquesubquery_engine::end_exec");
-  int error=0, tmp;
-  if ((tmp= table->file->extra(HA_EXTRA_NO_CACHE)))
-  {
-    DBUG_PRINT("error", ("extra(HA_EXTRA_NO_CACHE) failed"));
-    error= 1;
-  }
-  if ((tmp= table->file->index_end()))
-  {
-    DBUG_PRINT("error", ("index_end() failed"));
-    error= 1;
-  }
-  if (error == 1)
-    table->file->print_error(tmp, MYF(0));
-  DBUG_RETURN(error != 0);
+  /* Tell handler we don't need the index anymore */
+  tab->table->file->index_end();
 }
 
+
 int subselect_indexsubquery_engine::exec()
 {
   DBUG_ENTER("subselect_indexsubselect_engine::exec");
@@ -976,9 +972,11 @@ int subselect_indexsubquery_engine::exec()
   TABLE *table= tab->table;
 
   ((Item_in_subselect *) item)->value= 0;
+
   if (check_null)
   {
-    *tab->null_ref_key= 0;
+    /* We need to check for NULL if there wasn't a matching value */
+    *tab->null_ref_key= 0;			// Search first for not null
     ((Item_in_subselect *) item)->was_null= 0;
   }
 
@@ -996,7 +994,7 @@ int subselect_indexsubquery_engine::exec()
       error= report_error(table, error);
     else
     {
-      for(;;)
+      for (;;)
       {
 	error= 0;
 	table->null_row= 0;
@@ -1008,7 +1006,7 @@ int subselect_indexsubquery_engine::exec()
 	      ((Item_in_subselect *) item)->was_null= 1;
 	    else
 	      ((Item_in_subselect *) item)->value= 1;
-	    goto finish;
+	    break;
 	  }
 	  error= table->file->index_next_same(table->record[0],
 					      tab->ref.key_buff,
@@ -1016,25 +1014,26 @@ int subselect_indexsubquery_engine::exec()
 	  if (error && error != HA_ERR_END_OF_FILE)
 	  {
 	    error= report_error(table, error);
-	    goto finish;
+	    break;
 	  }
 	}
 	else
 	{
 	  if (!check_null || null_finding)
-	    goto finish;
+	    break;			/* We don't need to check nulls */
 	  *tab->null_ref_key= 1;
 	  null_finding= 1;
-	  if (safe_index_read(tab))
-	    goto finish;
+	  /* Check if there exists a row with a null value in the index */
+	  if ((error= safe_index_read(tab)))
+	    break;
 	}
       }
     }
   }
-finish:
-  DBUG_RETURN(end_exec(table) || (error != 0));
+  DBUG_RETURN(error != 0);
 }
 
+
 uint subselect_single_select_engine::cols()
 {
   return select_lex->item_list.elements;

sql/item_subselect.h

@@ -230,6 +230,7 @@ public:
   friend class subselect_indexsubquery_engine;
 };
 
+
 /* ALL/ANY/SOME subselect */
 class Item_allany_subselect :public Item_in_subselect
 {
@@ -244,6 +245,7 @@ public:
   trans_res select_transformer(JOIN *join);
 };
 
+
 class subselect_engine: public Sql_alloc
 {
 protected:
@@ -275,6 +277,7 @@ public:
   bool may_be_null() { return maybe_null; };
 };
 
+
 class subselect_single_select_engine: public subselect_engine
 {
   my_bool prepared; /* simple subselect is prepared */
@@ -295,6 +298,7 @@ public:
   void exclude();
 };
 
+
 class subselect_union_engine: public subselect_engine
 {
   st_select_lex_unit *unit;  /* corresponding unit structure */
@@ -312,6 +316,7 @@ public:
   void exclude();
 };
 
+
 struct st_join_table;
 class subselect_uniquesubquery_engine: public subselect_engine
 {
@@ -324,17 +329,17 @@ public:
 				  Item_subselect *subs, Item *where)
     :subselect_engine(thd, subs, 0), tab(tab_arg), cond(where)
   {}
-    
+  ~subselect_uniquesubquery_engine();
   int prepare();
   void fix_length_and_dec(Item_cache** row);
   int exec();
   uint cols() { return 1; }
   bool dependent() { return 1; }
   bool uncacheable() { return 1; }
-  void  exclude();
-  static int end_exec(TABLE *table);
+  void exclude();
 };
 
+
 class subselect_indexsubquery_engine: public subselect_uniquesubquery_engine
 {
   bool check_null;

sql/mysqld.cc

@@ -5610,14 +5610,16 @@ static uint set_maximum_open_files(uint max_file_limit)
     rlimit.rlim_cur=rlimit.rlim_max=max_file_limit;
     if (setrlimit(RLIMIT_NOFILE,&rlimit))
     {
-      sql_print_error("Warning: setrlimit couldn't increase number of open files to more than %lu (request: %u)",
-		      old_cur, max_file_limit);	/* purecov: inspected */
+      if (global_system_variables.log_warnings)
+	sql_print_error("Warning: setrlimit couldn't increase number of open files to more than %lu (request: %u)",
+			old_cur, max_file_limit); /* purecov: inspected */
       max_file_limit=old_cur;
     }
     else
     {
       (void) getrlimit(RLIMIT_NOFILE,&rlimit);
-      if ((uint) rlimit.rlim_cur != max_file_limit)
+      if ((uint) rlimit.rlim_cur != max_file_limit &&
+	  global_system_variables.log_warnings)
 	sql_print_error("Warning: setrlimit returned ok, but didn't change limits. Max open files is %ld (request: %u)",
 			(ulong) rlimit.rlim_cur,
 			max_file_limit); /* purecov: inspected */