Fixed bug in LOCK TABLE + DROP TABLE when other thread was waiting for a table...

Fixed bug in LOCK TABLE + DROP TABLE when other thread was waiting for a table that was locked bug not droped


client/mysqltest.c:
  Fixed bug that comments did a ping
include/thr_lock.h:
  Added function to abort a lock for a specific thread
mysql-test/mysql-test-run.sh:
  Fixed where mysqltest traces are put
mysql-test/r/lock_multi.result:
  Test for LOCK TABLE + DROP TABLE bug
mysql-test/t/lock_multi.test:
  Test for LOCK TABLE + DROP TABLE bug
mysys/thr_lock.c:
  Added function to abort a lock for a specific thread
sql/handler.cc:
  Indentation cleanup
sql/lock.cc:
  Added function to abort a lock for a specific thread
sql/mysql_priv.h:
  Added function to abort a lock for a specific thread
sql/mysqld.cc:
  Use automatic recover even with --safe

client/mysqltest.c

@@ -2484,6 +2484,7 @@ int main(int argc, char** argv)
       }
       case Q_COMMENT:				/* Ignore row */
       case Q_COMMENT_WITH_COMMAND:
+	break;
       case Q_PING:
 	(void) mysql_ping(&cur_con->mysql);
 	break;

include/thr_lock.h

@@ -107,6 +107,7 @@ void thr_unlock(THR_LOCK_DATA *data);
 int thr_multi_lock(THR_LOCK_DATA **data,uint count);
 void thr_multi_unlock(THR_LOCK_DATA **data,uint count);
 void thr_abort_locks(THR_LOCK *lock);
+void thr_abort_locks_for_thread(THR_LOCK *lock, pthread_t thread);
 void thr_print_locks(void);		/* For debugging */
 my_bool thr_upgrade_write_delay_lock(THR_LOCK_DATA *data);
 my_bool thr_reschedule_write_lock(THR_LOCK_DATA *data);

mysql-test/mysql-test-run.sh

@@ -349,7 +349,8 @@ while test $# -gt 0; do
        --debug=d:t:i:A,$MYSQL_TEST_DIR/var/log/master.trace"
       EXTRA_SLAVE_MYSQLD_OPT="$EXTRA_SLAVE_MYSQLD_OPT \
        --debug=d:t:i:A,$MYSQL_TEST_DIR/var/log/slave.trace"
-      EXTRA_MYSQL_TEST_OPT="$EXTRA_MYSQL_TEST_OPT --debug"
+      EXTRA_MYSQL_TEST_OPT="$EXTRA_MYSQL_TEST_OPT \
+       --debug=d:t:A,$MYSQL_TEST_DIR/var/log/mysqltest.trace"
       ;;
     --fast)
       FAST_START=1

mysql-test/r/lock_multi.result

-drop table if exists t1;
+drop table if exists t1,t2;
 create table t1(n int);
 insert into t1 values (1);
 lock tables t1 write;
@@ -17,3 +17,10 @@ unlock tables;
 n
 1
 drop table t1;
+create table t1 (a int);
+create table t2 (a int);
+lock table t1 write, t2 write;
+ insert t1 select * from t2;
+drop table t2;
+Table 'test.t2' doesn't exist
+drop table t1;

mysql-test/t/lock_multi.test

@@ -6,8 +6,9 @@
 #
 -- source include/not_embedded.inc
 
-drop table if exists t1;
-#test to see if select will get the lock ahead of low priority update
+drop table if exists t1,t2;
+
+# test to see if select will get the lock ahead of low priority update
 
 connect (locker,localhost,root,,);
 connect (reader,localhost,root,,);
@@ -48,3 +49,22 @@ reap;
 connection reader;
 reap;
 drop table t1;
+
+#
+# Test problem when using locks on many tables and droping a table that
+# is to-be-locked by another thread
+#
+
+connection locker;
+create table t1 (a int);
+create table t2 (a int);
+lock table t1 write, t2 write;
+connection reader;
+send insert t1 select * from t2;
+connection locker;
+drop table t2;
+connection reader;
+--error 1146
+reap;
+connection locker;
+drop table t1;

mysys/thr_lock.c

@@ -945,6 +945,54 @@ void thr_abort_locks(THR_LOCK *lock)
 }
 
 
+/*
+  Abort all locks for specific table/thread combination
+
+  This is used to abort all locks for a specific thread
+*/
+
+void thr_abort_locks_for_thread(THR_LOCK *lock, pthread_t thread)
+{
+  THR_LOCK_DATA *data;
+  DBUG_ENTER("thr_abort_locks_for_thread");
+
+  pthread_mutex_lock(&lock->mutex);
+  for (data= lock->read_wait.data; data ; data= data->next)
+  {
+    if (pthread_equal(thread, data->thread))
+    {
+      DBUG_PRINT("info",("Aborting read-wait lock"));
+      data->type= TL_UNLOCK;			/* Mark killed */
+      pthread_cond_signal(data->cond);
+      data->cond= 0;				/* Removed from list */
+
+      if (((*data->prev)= data->next))
+	data->next->prev= data->prev;
+      else
+	lock->read_wait.last= data->prev;
+    }
+  }
+  for (data= lock->write_wait.data; data ; data= data->next)
+  {
+    if (pthread_equal(thread, data->thread))
+    {
+      DBUG_PRINT("info",("Aborting write-wait lock"));
+      data->type= TL_UNLOCK;
+      pthread_cond_signal(data->cond);
+      data->cond= 0;
+
+      if (((*data->prev)= data->next))
+	data->next->prev= data->prev;
+      else
+	lock->write_wait.last= data->prev;
+    }
+  }
+  pthread_mutex_unlock(&lock->mutex);
+  DBUG_VOID_RETURN;
+}
+
+
+
 /* Upgrade a WRITE_DELAY lock to a WRITE_LOCK */
 
 my_bool thr_upgrade_write_delay_lock(THR_LOCK_DATA *data)

sql/handler.cc

@@ -473,7 +473,8 @@ int handler::ha_open(const char *name, int mode, int test_if_locked)
   int error;
   DBUG_ENTER("handler::open");
   DBUG_PRINT("enter",("name: %s  db_type: %d  db_stat: %d  mode: %d  lock_test: %d",
-		      name, table->db_type, table->db_stat, mode, test_if_locked));
+		      name, table->db_type, table->db_stat, mode,
+		      test_if_locked));
 
   if ((error=open(name,mode,test_if_locked)))
   {

sql/lock.cc

@@ -313,6 +313,25 @@ void mysql_lock_abort(THD *thd, TABLE *table)
 }
 
 
+/* Abort one thread / table combination */
+
+void mysql_lock_abort_for_thread(THD *thd, TABLE *table)
+{
+  MYSQL_LOCK *locked;
+  TABLE *write_lock_used;
+  DBUG_ENTER("mysql_lock_abort_for_thread");
+
+  if ((locked = get_lock_data(thd,&table,1,1,&write_lock_used)))
+  {
+    for (uint i=0; i < locked->lock_count; i++)
+      thr_abort_locks_for_thread(locked->locks[i]->lock,
+				 table->in_use->real_id);
+    my_free((gptr) locked,MYF(0));
+  }
+  DBUG_VOID_RETURN;
+}
+
+
 MYSQL_LOCK *mysql_lock_merge(MYSQL_LOCK *a,MYSQL_LOCK *b)
 {
   MYSQL_LOCK *sql_lock;

sql/mysql_priv.h

@@ -711,6 +711,7 @@ void mysql_unlock_read_tables(THD *thd, MYSQL_LOCK *sql_lock);
 void mysql_unlock_some_tables(THD *thd, TABLE **table,uint count);
 void mysql_lock_remove(THD *thd, MYSQL_LOCK *locked,TABLE *table);
 void mysql_lock_abort(THD *thd, TABLE *table);
+void mysql_lock_abort_for_thread(THD *thd, TABLE *table);
 MYSQL_LOCK *mysql_lock_merge(MYSQL_LOCK *a,MYSQL_LOCK *b);
 bool lock_global_read_lock(THD *thd);
 void unlock_global_read_lock(THD *thd);

sql/mysqld.cc

@@ -4416,8 +4416,8 @@ get_one_option(int optid, const struct my_option *opt __attribute__((unused)),
   case (int) OPT_SAFE:
     opt_specialflag|= SPECIAL_SAFE_MODE;
     delay_key_write_options= (uint) DELAY_KEY_WRITE_NONE;
-    myisam_recover_options= HA_RECOVER_NONE;	// To be changed
-    ha_open_options&= ~(HA_OPEN_ABORT_IF_CRASHED | HA_OPEN_DELAY_KEY_WRITE);
+    myisam_recover_options= HA_RECOVER_DEFAULT;
+    ha_open_options&= ~(HA_OPEN_DELAY_KEY_WRITE);
     break;
   case (int) OPT_SKIP_PRIOR:
     opt_specialflag|= SPECIAL_NO_PRIOR;

sql/sql_base.cc

@@ -1244,25 +1244,44 @@ bool drop_locked_tables(THD *thd,const char *db, const char *table_name)
 }
 
 
-/* lock table to force abort of any threads trying to use table */
+/*
+  If we have the table open, which only happens when a LOCK TABLE has been
+  done on the table, change the lock type to a lock that will abort all
+  other threads trying to get the lock.
+*/
 
 void abort_locked_tables(THD *thd,const char *db, const char *table_name)
 {
   TABLE *table;
-  for (table=thd->open_tables; table ; table=table->next)
+  for (table= thd->open_tables; table ; table= table->next)
   {
     if (!strcmp(table->real_name,table_name) &&
 	!strcmp(table->table_cache_key,db))
+    {
       mysql_lock_abort(thd,table);
+      break;
+    }
   }
 }
 
-/****************************************************************************
-**	open_unireg_entry
-**	Purpose : Load a table definition from file and open unireg table
-**	Args	: entry with DB and table given
-**	Returns : 0 if ok
-**	Note that the extra argument for open is taken from thd->open_options
+
+/*
+  Load a table definition from file and open unireg table
+
+  SYNOPSIS
+    open_unireg_entry()
+    thd			Thread handle
+    entry		Store open table definition here
+    db			Database name
+    name		Table name
+    alias		Alias name
+
+  NOTES
+   Extra argument for open is taken from thd->open_options
+
+  RETURN
+    0	ok
+    #	Error
 */
 
 static int open_unireg_entry(THD *thd, TABLE *entry, const char *db,
@@ -2277,6 +2296,17 @@ bool remove_table_from_cache(THD *thd, const char *db, const char *table_name,
 	}
 	pthread_mutex_unlock(&in_use->mysys_var->mutex);
       }
+      /*
+	Now we must abort all tables locks used by this thread
+	as the thread may be waiting to get a lock for another table
+      */
+      for (TABLE *thd_table= in_use->open_tables;
+	   thd_table ;
+	   thd_table= thd_table->next)
+      {
+	if (thd_table->db_stat)			// If table is open
+	  mysql_lock_abort_for_thread(thd, thd_table);
+      }
     }
     else
       result= result || return_if_owned_by_thd;