Added some missing mutex_locks() when manipulating the table cache.

This should fix some possible table cache corruptions when doing
OPTIMIZE or REPAIR table when other threads are opening new tables.


sql/sql_base.cc:
  Added missing mutex unlock on error condition
sql/sql_insert.cc:
  Added TODO item
sql/sql_show.cc:
  Added missing pthread_mutex_lock(&LOCK_open) when calling
  query_table_status().
sql/sql_table.cc:
  Added missing pthread_mutex_lock(&LOCK_open) when calling
  hash_delete(), unlock_table_name() and remove_table_from_cache().
BitKeeper/etc/logging_ok:
  Logging to logging@openlogging.org accepted

BitKeeper/etc/logging_ok

@@ -25,3 +25,4 @@ zak@balfor.local
 monty@narttu.
 monty@mashka.mysql.fi
 bar@bar.udmsearch.izhnet.ru
+monty@narttu.mysql.fi

sql/sql_base.cc

@@ -279,6 +279,16 @@ void intern_close_table(TABLE *table)
     VOID(closefrm(table));			// close file
 }
 
+/*
+  Remove table from the open table cache
+
+  SYNOPSIS
+    free_cache_entry()
+    table		Table to remove
+
+  NOTE
+    We need to have a lock on LOCK_open when calling this
+*/
 
 static void free_cache_entry(TABLE *table)
 {
@@ -833,7 +843,10 @@ TABLE *open_table(THD *thd,const char *db,const char *table_name,
 
     /* make a new table */
     if (!(table=(TABLE*) my_malloc(sizeof(*table),MYF(MY_WME))))
+    {
+      VOID(pthread_mutex_unlock(&LOCK_open));
       DBUG_RETURN(NULL);
+    }
     if (open_unireg_entry(thd, table,db,table_name,alias,1) ||
 	!(table->table_cache_key=memdup_root(&table->mem_root,(char*) key,
 					     key_length)))
@@ -1181,7 +1194,6 @@ bool wait_for_tables(THD *thd)
     /* Now we can open all tables without any interference */
     thd->proc_info="Reopen tables";
     result=reopen_tables(thd,0,0);
-     
   }
   pthread_mutex_unlock(&LOCK_open);
   thd->proc_info=0;
@@ -1372,9 +1384,9 @@ int open_tables(THD *thd,TABLE_LIST *start)
 	  }
 	}
 	*prev_table=0;
+	pthread_mutex_unlock(&LOCK_open);
 	if (found)
 	  VOID(pthread_cond_broadcast(&COND_refresh)); // Signal to refresh
-	pthread_mutex_unlock(&LOCK_open);
 	goto restart;
       }
       result= -1;				// Fatal error

sql/sql_insert.cc

@@ -1419,6 +1419,11 @@ bool select_create::send_eof()
     table->file->extra(HA_EXTRA_NO_IGNORE_DUP_KEY);
     VOID(pthread_mutex_lock(&LOCK_open));
     mysql_unlock_tables(thd, lock);
+    /*
+      TODO:
+      Check if we can remove the following two rows.
+      We should be able to just keep the table in the table cache.
+    */
     if (!table->tmp_table)
       hash_delete(&open_cache,(byte*) table);
     lock=0; table=0;

sql/sql_show.cc

@@ -117,6 +117,7 @@ int mysqld_show_open_tables(THD *thd,const char *db,const char *wild)
   if (list_open_tables(thd,&tables,db,wild))
     DBUG_RETURN(-1);
 
+  pthread_mutex_lock(&LOCK_open);
   List_iterator<char> it(tables);
   while ((table_name=it++))
   {
@@ -124,13 +125,17 @@ int mysqld_show_open_tables(THD *thd,const char *db,const char *wild)
     net_store_data(&thd->packet,table_name);
     net_store_data(&thd->packet,query_table_status(thd,db,table_name));
     if (my_net_write(&thd->net,(char*) thd->packet.ptr(),thd->packet.length()))
+    {
+      pthread_mutex_unlock(&LOCK_open);
       DBUG_RETURN(-1);
+    }
   }
-
+  pthread_mutex_unlock(&LOCK_open);
   send_eof(&thd->net);
   DBUG_RETURN(0);
 }
 
+
 /***************************************************************************
 ** List all tables in a database (fast version)
 ** A table is a .frm file in the current databasedir

sql/sql_table.cc

@@ -147,8 +147,8 @@ int mysql_rm_table(THD *thd,TABLE_LIST *tables, my_bool if_exists)
   
   error = 0;
  err:  
-  VOID(pthread_cond_broadcast(&COND_refresh)); // Signal to refresh
   pthread_mutex_unlock(&LOCK_open);
+  VOID(pthread_cond_broadcast(&COND_refresh)); // Signal to refresh
 
   pthread_mutex_lock(&thd->mysys_var->mutex);
   thd->mysys_var->current_mutex= 0;
@@ -160,7 +160,7 @@ int mysql_rm_table(THD *thd,TABLE_LIST *tables, my_bool if_exists)
     my_error(ER_BAD_TABLE_ERROR,MYF(0),wrong_tables.c_ptr());
     error=1;
   }
-  if(error)
+  if (error)
     DBUG_RETURN(-1);
   send_ok(&thd->net);
   DBUG_RETURN(0);
@@ -711,7 +711,9 @@ TABLE *create_table_from_items(THD *thd, HA_CREATE_INFO *create_info,
   table->reginfo.lock_type=TL_WRITE;
   if (!((*lock)=mysql_lock_tables(thd,&table,1)))
   {
+    VOID(pthread_mutex_lock(&LOCK_open));
     hash_delete(&open_cache,(byte*) table);
+    VOID(pthread_mutex_unlock(&LOCK_open));
     quick_rm_table(create_info->db_type,db,name);
     DBUG_RETURN(0);
   }
@@ -859,7 +861,9 @@ static int prepare_for_restore(THD* thd, TABLE_LIST* table)
 			 reg_ext, 4),
 	       MYF(MY_WME)))
     {
+      pthread_mutex_lock(&LOCK_open);
       unlock_table_name(thd, table);
+      pthread_mutex_unlock(&LOCK_open);
       DBUG_RETURN(send_check_errmsg(thd, table, "restore",
 				    "Failed copying .frm file"));
     }
@@ -870,7 +874,9 @@ static int prepare_for_restore(THD* thd, TABLE_LIST* table)
 
     if (generate_table(thd, table, 0))
     {
+      pthread_mutex_lock(&LOCK_open);
       unlock_table_name(thd, table);
+      pthread_mutex_unlock(&LOCK_open);
       thd->net.no_send_ok = save_no_send_ok;
       DBUG_RETURN(send_check_errmsg(thd, table, "restore",
 				    "Failed generating table from .frm file"));
@@ -930,9 +936,12 @@ static int mysql_admin_table(THD* thd, TABLE_LIST* tables,
       // now we should be able to open the partially restored table
       // to finish the restore in the handler later on
       if (!(table->table = reopen_name_locked_table(thd, table)))
+      {
+	pthread_mutex_lock(&LOCK_open);
         unlock_table_name(thd, table);
+	pthread_mutex_unlock(&LOCK_open);
+      }
     }
-
     if (!table->table)
     {
       const char *err_msg;
@@ -1031,8 +1040,12 @@ static int mysql_admin_table(THD* thd, TABLE_LIST* tables,
     if (fatal_error)
       table->table->version=0;			// Force close of table
     else if (open_for_modify)
+    {
+      pthread_mutex_lock(&LOCK_open);
       remove_table_from_cache(thd, table->table->table_cache_key,
 			      table->table->real_name);
+      pthread_mutex_unlock(&LOCK_open);
+    }
     close_thread_tables(thd);
     if (my_net_write(&thd->net, (char*) packet->ptr(),
 		     packet->length()))
@@ -1648,8 +1661,8 @@ int mysql_alter_table(THD *thd,char *new_db, char *new_name,
     error=1;
   if (error)
   {
-    VOID(pthread_cond_broadcast(&COND_refresh));
     VOID(pthread_mutex_unlock(&LOCK_open));
+    VOID(pthread_cond_broadcast(&COND_refresh));
     goto err;
   }
 #ifdef HAVE_BERKELEY_DB