Merge of last changes

sql/ChangeLog:
  Update of last changes
sql/mysql_priv.h:
  RENAME TABLE
sql/sql_parse.cc:
  RENAME TABLE ; MORE Access checks; Faster alloc

sql/ChangeLog

+2000-08-21  Michael Widenius  <monty@mysql.com>
+
+* Added RENAME TABLE.
+
 2000-08-20  Michael Widenius  <monty@mysql.com>
 
 * Added memory as inline functions to THD to get them a bit faster

sql/mysql_priv.h

@@ -217,6 +217,7 @@ void mysql_binlog_send(THD* thd, char* log_ident, ulong pos, ushort flags);
 int mysql_rm_table(THD *thd,TABLE_LIST *tables, my_bool if_exists);
 int quick_rm_table(enum db_type base,const char *db,
 		   const char *table_name);
+bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list);
 bool mysql_change_db(THD *thd,const char *name);
 void mysql_parse(THD *thd,char *inBuf,uint length);
 void mysql_init_select(LEX *lex);
@@ -293,6 +294,11 @@ int mysql_alter_table(THD *thd, char *new_db, char *new_name,
 		      List<Alter_column> &alter_list,
 		      bool drop_primary,
 		      enum enum_duplicates handle_duplicates);
+bool mysql_rename_table(enum db_type base,
+			const char *old_db,
+			const char * old_name,
+			const char *new_db,
+			const char * new_name);
 bool close_cached_table(THD *thd,TABLE *table);
 int mysql_create_index(THD *thd, TABLE_LIST *table_list, List<Key> &keys);
 int mysql_drop_index(THD *thd, TABLE_LIST *table_list,
@@ -316,6 +322,7 @@ bool reopen_tables(THD *thd,bool get_locks,bool in_refresh);
 void close_old_data_files(THD *thd, TABLE *table, bool abort_locks);
 bool close_data_tables(THD *thd,const char *db, const char *table_name);
 bool wait_for_tables(THD *thd);
+bool table_is_used(TABLE *table);
 bool drop_locked_tables(THD *thd,const char *db, const char *table_name);
 void abort_locked_tables(THD *thd,const char *db, const char *table_name);
 Field *find_field_in_tables(THD *thd,Item_field *item,TABLE_LIST *tables);
@@ -488,6 +495,11 @@ void mysql_lock_remove(THD *thd, MYSQL_LOCK *locked,TABLE *table);
 void mysql_lock_abort(THD *thd, TABLE *table);
 MYSQL_LOCK *mysql_lock_merge(MYSQL_LOCK *a,MYSQL_LOCK *b);
 
+/* Lock based on name */
+int lock_table_name(THD *thd, TABLE_LIST *table_list);
+void unlock_table_name(THD *thd, TABLE_LIST *table_list);
+bool wait_for_locked_table_names(THD *thd, TABLE_LIST *table_list);
+
 extern int flush_master_info(MASTER_INFO* mi);
 
 /* old unireg functions */

sql/sql_rename.cc

+/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+/*
+  Atomic rename of table;  RENAME TABLE t1 to t2, tmp to t1 [,...]
+*/
+
+#include "mysql_priv.h"
+
+
+static TABLE_LIST *mysql_rename_tables(THD *thd, TABLE_LIST *table_list,
+				       bool skip_error);
+
+/*
+  Every second entry in the table_list is the original name and every
+  second entry is the new name.
+*/
+
+bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list)
+{
+  bool error=1,got_all_locks=1;
+  db_type table_type;
+  TABLE_LIST *lock_table,*ren_table=0,*new_table;
+  DBUG_ENTER("mysql_rename_tables");
+  
+  /* Avoid problems with a rename on a table that we have locked or
+     if the user is trying to to do this in a transcation context */
+
+  if (thd->locked_tables || thd->active_transaction())
+  {
+    my_error(ER_LOCK_OR_ACTIVE_TRANSACTION,MYF(0));
+    DBUG_RETURN(1);
+  }
+      
+  VOID(pthread_mutex_lock(&LOCK_open));
+  for (lock_table=table_list ; lock_table ; lock_table=lock_table->next)
+  {
+    int got_lock;
+    if ((got_lock=lock_table_name(thd,lock_table)) < 0)
+      goto end;
+    if (got_lock)
+      got_all_locks=0;
+  }
+  
+  if (!got_all_locks && wait_for_locked_table_names(thd,table_list))
+    goto end;
+
+  if (!(ren_table=mysql_rename_tables(thd,table_list,0)))
+    error=0;
+  
+end:
+  if (ren_table)
+  {
+    /* Rename didn't succeed;  rename back the tables in reverse order */
+    TABLE_LIST *prev=0,*table;
+    /*
+      Reverse the table list ; Note that we need to handle the case that
+      every second entry must stay in place in respect to the previous
+    */
+    while (table_list)
+    {
+      TABLE_LIST *next=table_list->next->next;
+      table_list->next->next=prev;
+      prev=table_list;
+      table_list=next;
+    }
+    table_list=prev;
+
+    /* Find the last renamed table */
+    for (table=table_list ; table->next != ren_table ;
+	 table=table->next->next) ;
+    table=table->next->next;			// Skipp error table
+    /* Revert to old names */
+    mysql_rename_tables(thd, table, 1);
+    /* Note that lock_table == 0 here, so the unlock loop will work */
+  }
+  if (!error)
+  {
+    mysql_update_log.write(thd->query,thd->query_length);
+    Query_log_event qinfo(thd, thd->query);
+    mysql_bin_log.write(&qinfo);
+  }
+  for (TABLE_LIST *table=table_list ; table != lock_table ; table=table->next)
+    unlock_table_name(thd,table);
+  pthread_cond_broadcast(&COND_refresh);
+  pthread_mutex_unlock(&LOCK_open);
+  DBUG_RETURN(error);
+}
+
+
+/*
+  Rename all tables in list; Return pointer to wrong entry if something goes
+  wrong.
+*/
+
+static TABLE_LIST *
+mysql_rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
+{
+  TABLE_LIST *ren_table;
+  for (ren_table=table_list ; ren_table ; ren_table=ren_table->next)
+  {
+    db_type table_type;
+    char name[FN_REFLEN];
+    TABLE_LIST *new_table=ren_table->next;
+
+    sprintf(name,"%s/%s/%s%s",mysql_data_home,
+	    ren_table->db,ren_table->name,
+	    reg_ext);
+    if ((table_type=get_table_type(name)) == DB_TYPE_UNKNOWN ||
+	mysql_rename_table(table_type,
+			   ren_table->db, ren_table->name,
+			   new_table->db, new_table->name))
+    {
+      if (!skip_error)
+	return ren_table;
+    }
+  }
+  return 0;
+}