Fix of UNION code

Added heap_delete_table
Added HA_EXTRA_PREPARE_FOR_DELETE
Added and use my_dup() for faster open of tables.
Removed not working no-mix-table-type


BitKeeper/deleted/.del-=6~33f33b0a159dc5d5:
  Delete: =6
heap/hp_clear.c:
  Cleanup
heap/hp_close.c:
  Added delayed delete
heap/hp_create.c:
  Added heap_delete_table
heap/hp_delete.c:
  cleanup
heap/hp_test2.c:
  Added heap_delete_table
include/heap.h:
  Added heap_delete_table
include/my_base.h:
  Added HA_EXTRA_PREPARE_FOR_DELETE
include/my_sys.h:
  Adde my_dup and set_prealloc_root
isam/extra.c:
  Added HA_EXTRA_PREPARE_FOR_DELETE
myisam/mi_check.c:
  use my_dup
myisam/mi_extra.c:
  use my_dup
myisam/mi_open.c:
  use my_dup
myisam/myisamchk.c:
  use my_dup
myisam/myisamdef.h:
  use my_dup
mysys/Makefile.am:
  my_dup
mysys/hash.c:
  Add hash_replace
mysys/mf_pack.c:
  cleanup
mysys/my_alloc.c:
  Add set_prealloc_root
mysys/my_fstream.c:
  cleanup
mysys/my_lib.c:
  cleanup
mysys/my_seek.c:
  cleanup
sql/ha_heap.cc:
  Uses heap_delete_table()
sql/mysqld.cc:
  Fix SIGHUP usage
  Remove no-mix-table-types
sql/share/czech/errmsg.txt:
  new error message
sql/share/danish/errmsg.txt:
  new error message
sql/share/dutch/errmsg.txt:
  new error message
sql/share/english/errmsg.txt:
  new error message
sql/share/estonian/errmsg.txt:
  new error message
sql/share/french/errmsg.txt:
  new error message
sql/share/german/errmsg.txt:
  new error message
sql/share/greek/errmsg.txt:
  new error message
sql/share/hungarian/errmsg.txt:
  new error message
sql/share/italian/errmsg.txt:
  new error message
sql/share/japanese/errmsg.txt:
  new error message
sql/share/korean/errmsg.txt:
  new error message
sql/share/norwegian-ny/errmsg.txt:
  new error message
sql/share/norwegian/errmsg.txt:
  new error message
sql/share/polish/errmsg.txt:
  new error message
sql/share/portuguese/errmsg.txt:
  new error message
sql/share/romanian/errmsg.txt:
  new error message
sql/share/russian/errmsg.txt:
  new error message
sql/share/slovak/errmsg.txt:
  new error message
sql/share/spanish/errmsg.txt:
  new error message
sql/share/swedish/errmsg.txt:
  new error message
sql/sql_base.cc:
  remove no-mix-table-type
sql/sql_parse.cc:
  Fix UNION code

1 files changed, 26 insertions, 0 deletions

diff --git a/mysys/my_alloc.c b/mysys/my_alloc.c
index ffbed381226..0c61d2ede3c 100644
--- a/mysys/my_alloc.c
+++ b/mysys/my_alloc.c
@@ -55,6 +55,7 @@ gptr alloc_root(MEM_ROOT *mem_root,unsigned int Size)
     return((gptr) 0);				/* purecov: inspected */
   }
   next->next=mem_root->used;
+  next->size= Size;
   mem_root->used=next;
   return (gptr) (((char*) next)+ALIGN_SIZE(sizeof(USED_MEM)));
 #else
@@ -166,6 +167,31 @@ void free_root(MEM_ROOT *root, myf MyFlags)
   DBUG_VOID_RETURN;
 }
 
+/*
+  Find block that contains an object and set the pre_alloc to it
+*/
+
+void set_prealloc_root(MEM_ROOT *root, char *ptr)
+{
+  USED_MEM *next;
+  for (next=root->used; next ; next=next->next)
+  {
+    if ((char*) next <= ptr && (char*) next + next->size > ptr)
+    {
+      root->pre_alloc=next;
+      return;
+    }
+  }
+  for (next=root->free ; next ; next=next->next)
+  {
+    if ((char*) next <= ptr && (char*) next + next->size > ptr)
+    {
+      root->pre_alloc=next;
+      return;
+    }
+  }
+}  
+
 
 char *strdup_root(MEM_ROOT *root,const char *str)
 {