Added support for a LOCK TABLES...WHERE ENGINE = InnoDB query which sets

transactional table locks to tables mentioned in the query. These locks
are released at the end of the transaction automatically.
This is fix for bugs #5655, #5998 and issue #3762.




innobase/include/lock0lock.h:
  Added a new lock type LOCK_TABLE_TRANSACTIONAL.
innobase/include/trx0trx.h:
  Added a varible to store the number of transactional table locks
  reserved by the transaction and stored in the trx_locks list.
innobase/lock/lock0lock.c:
  Added a lock type LOCK_TABLE_TRANSACTIONAL.
innobase/row/row0mysql.c:
  Added support for a transactional table lock.
innobase/trx/trx0roll.c:
  Make compiler happy and format function.
innobase/trx/trx0trx.c:
  Added information about number of explicit and transactional table locks in
  the innodb monitor.
sql/ha_innodb.cc:
  Added support for a LOCK_TABLE_TRANSACTIONAL table lock (SQLCOM_LOCK_TABLES_TRANSACTIONAL).
  Transactional table locks are taken in the function ::transactional_table_lock().
sql/ha_innodb.h:
  Added prototype for a function trandactional_table_lock().
sql/handler.h:
  Added prototype for a virtual function transactional_table_lock().
  Handler does not need to implement this function.
sql/lock.cc:
  Added a function transactional_lock_tables() to lock all tables in the list
  with transactional table lock. These locks can cause a deadlock and
  this error should be reported back to user.
sql/mysql_priv.h:
  Added prototype for a function transactional_lock_tables().
sql/sql_lex.h:
  Added SQLCOM_LOCK_TABLES_TRANSACTIONAL command.
sql/sql_parse.cc:
  Added SQLCOM_LOCK_TABLES_TRANSACTIONAL command.
sql/sql_yacc.yy:
  Added parsing rules for a LOCK TABLES...WHERE ENGINE = x;

1 files changed, 62 insertions, 0 deletions

diff --git a/sql/lock.cc b/sql/lock.cc
index 3367c6a2900..0db23f54c50 100644
--- a/sql/lock.cc
+++ b/sql/lock.cc
@@ -695,6 +695,9 @@ static void print_lock_error(int error)
   case HA_ERR_READ_ONLY_TRANSACTION:
     textno=ER_READ_ONLY_TRANSACTION;
     break;
+  case HA_ERR_LOCK_DEADLOCK:
+    textno=ER_LOCK_DEADLOCK;
+    break;
   default:
     textno=ER_CANT_LOCK;
     break;
@@ -870,3 +873,62 @@ bool make_global_read_lock_block_commit(THD *thd)
   thd->exit_cond(old_message);
   DBUG_RETURN(error);
 }
+
+/*
+  Take transactional table lock for all tables in the list
+
+  SYNOPSIS
+    transactional_lock_tables
+    thd			Thread THD
+    tables              list of tables
+    counter             number of tables in the list
+
+  NOTES
+
+  RETURN
+    0  - OK
+    -1 - error
+
+*/
+int transactional_lock_tables(THD *thd, TABLE_LIST *tables, uint counter)
+{ 
+  uint i;
+  int lock_type,error=0;
+  TABLE_LIST *table;
+  TABLE **start,**ptr;
+
+  DBUG_ENTER("transactional_lock_tables");
+
+  if (!(ptr=start=(TABLE**) sql_alloc(sizeof(TABLE*) * counter)))
+      return -1;
+    
+  for (table= tables; table; table= table->next_global)
+  {
+    if (!table->placeholder() && !table->schema_table)
+      *(ptr++)= table->table;
+  }
+
+  for (i=1 ; i <= counter ; i++, start++)
+  {
+    DBUG_ASSERT((*start)->reginfo.lock_type >= TL_READ);
+    lock_type=F_WRLCK;				/* Lock exclusive */
+
+    if ((*start)->db_stat & HA_READ_ONLY ||
+       ((*start)->reginfo.lock_type >= TL_READ &&
+	(*start)->reginfo.lock_type <= TL_READ_NO_INSERT))
+      lock_type=F_RDLCK;
+
+    if ((error=(*start)->file->transactional_table_lock(thd, lock_type)))
+    {
+      print_lock_error(error);
+      DBUG_RETURN(-1);
+    }
+    else
+    {
+      (*start)->db_stat &= ~ HA_BLOCK_LOCK;
+      (*start)->current_lock= lock_type;
+    }
+  }
+
+  DBUG_RETURN(0);
+}