Merge abotchkov@work.mysql.com:/home/bk/mysql-4.1

into deer.mysql.r18.ru:/home/hf/work/mysql-default

sql/field.h

@@ -78,10 +78,11 @@ public:
   virtual void reset_fields() {}
   virtual void set_default()
   {
-    memcpy(ptr, ptr + table->rec_buff_length, pack_length());
+    my_ptrdiff_t offset = table->default_values() - table->record[0];
+    memcpy(ptr, ptr + offset, pack_length());
     if (null_ptr)
       *null_ptr= ((*null_ptr & (uchar) ~null_bit) |
-		  null_ptr[table->rec_buff_length] & null_bit);
+		  null_ptr[offset] & null_bit);
   }
   virtual bool binary() const { return 1; }
   virtual bool zero_pack() const { return 1; }

sql/item.cc

@@ -1126,6 +1126,52 @@ bool Item_ref::check_loop(uint id)
   DBUG_RETURN((*ref)->check_loop(id));
 }
 
+bool Item_default_value::eq(const Item *item, bool binary_cmp) const
+{
+  return item->type() == DEFAULT_ITEM && 
+    ((Item_default_value *)item)->arg->eq(arg, binary_cmp);
+}
+
+bool Item_default_value::fix_fields(THD *thd, struct st_table_list *table_list, Item **items)
+{
+  if (!arg)
+    return false;
+  bool res= arg->fix_fields(thd, table_list, items);
+  if (res)
+    return res;
+  /* arg->type() can be only REF_ITEM or FIELD_ITEM for it defined as
+   simple_ident in sql_yacc.yy
+  */
+  if (arg->type() == REF_ITEM)
+  {
+    Item_ref *ref= (Item_ref *)arg;
+    if (ref->ref[0]->type() != FIELD_ITEM)
+    {
+      return 1;
+    }
+    arg= ref->ref[0];
+  }
+  Item_field *field_arg= (Item_field *)arg;
+  Field *def_field= (Field*) sql_alloc(field_arg->field->size_of());
+  if (!def_field)
+    return 1;
+  memcpy(def_field, field_arg->field, field_arg->field->size_of());
+  def_field->move_field(def_field->table->default_values() - 
+			def_field->table->record[0]);
+  set_field(def_field);
+  return 0;
+}
+
+void Item_default_value::print(String *str)
+{
+  if (!arg)
+  {
+    str->append("DEFAULT");
+  }
+  str->append("DEFAULT(");
+  arg->print(str);
+  str->append(')');
+}
 
 /*
   If item is a const function, calculate it and return a const item

sql/item.h

@@ -37,6 +37,7 @@ public:
 	     PROC_ITEM,COND_ITEM, REF_ITEM, FIELD_STD_ITEM, 
 	     FIELD_VARIANCE_ITEM, CONST_ITEM,
              SUBSELECT_ITEM, ROW_ITEM, CACHE_ITEM};
+
   enum cond_result { COND_UNDEF,COND_OK,COND_TRUE,COND_FALSE };
 
   String str_value;			/* used to store value */
@@ -167,9 +168,9 @@ public:
   bool get_date(TIME *ltime,bool fuzzydate);  
   bool get_time(TIME *ltime);  
   bool is_null() { return field->is_null(); }
+  friend class Item_default_value;
 };
 
-
 class Item_null :public Item
 {
 public:
@@ -370,26 +371,6 @@ public:
   void print(String *str);
 };
 
-
-/* For INSERT ... VALUES (DEFAULT) */
-
-class Item_default :public Item
-{
-public:
-  Item_default() { name= (char*) "DEFAULT"; }
-  enum Type type() const { return DEFAULT_ITEM; }
-  int save_in_field(Field *field, bool no_conversions)
-  {
-    field->set_default();
-    return 0;
-  }
-  virtual double val() { return 0.0; }
-  virtual longlong val_int() { return 0; }
-  virtual String *val_str(String *str) { return 0; }
-  bool basic_const_item() const { return 1; }
-};
-
-
 /* for show tables */
 
 class Item_datetime :public Item_string
@@ -674,6 +655,41 @@ public:
   bool cmp(void);
 };
 
+class Item_default_value : public Item_field
+{
+public:
+  Item *arg;
+  Item_default_value() :
+    Item_field((const char *)NULL, (const char *)NULL, (const char *)NULL), arg(NULL) {}
+  Item_default_value(Item *a) : 
+    Item_field((const char *)NULL, (const char *)NULL, (const char *)NULL), arg(a) {}
+  enum Type type() const { return DEFAULT_ITEM; }
+  bool eq(const Item *item, bool binary_cmp) const;
+  bool fix_fields(THD *, struct st_table_list *, Item **);
+  bool check_loop(uint id)
+  {
+    return Item_field::check_loop(id) || arg->check_loop(id);
+  }
+  void set_outer_resolving() { arg->set_outer_resolving(); }
+  void print(String *str);
+  virtual bool basic_const_item() const { return true; }
+  int save_in_field(Field *field, bool no_conversions)
+  {
+    if (!arg)
+    {
+      field->set_default();
+      return 0;
+    }
+    return Item_field::save_in_field(field, no_conversions);
+  }
+  table_map used_tables() const
+  { 
+    if (!arg)
+      return (table_map) 0L; 
+    return Item_field::used_tables();
+  }
+};
+
 class Item_cache: public Item
 {
 public:

sql/sql_yacc.yy

@@ -1863,8 +1863,10 @@ optional_braces:
 	| '(' ')' {};
 
 /* all possible expressions */
-expr:	expr_expr	{ $$= $1; }
-	| simple_expr	{ $$= $1; };
+expr:	
+	expr_expr	{ $$= $1; }
+	| simple_expr	{ $$= $1; }
+	;
 
 comp_op:  EQ		{ $$ = &comp_eq_creator; }
 	| GE		{ $$ = &comp_ge_creator; }
@@ -2087,6 +2089,8 @@ simple_expr:
 	  { $$= new Item_func_conv_charset($3,$5); }
 	| CONVERT_SYM '(' expr ',' expr ',' expr ')'
 	  { $$= new Item_func_conv_charset3($3,$7,$5); }
+	| DEFAULT '(' simple_ident ')'
+	  { $$= new Item_default_value($3); }
 	| FUNC_ARG0 '(' ')'
 	  { $$= ((Item*(*)(void))($1.symbol->create_func))();}
 	| FUNC_ARG1 '(' expr ')'
@@ -3178,7 +3182,7 @@ values:
 
 expr_or_default:
 	expr	  { $$= $1;}
-	| DEFAULT {$$= new Item_default(); }
+	| DEFAULT {$$= new Item_default_value(); }
 	;
 
 opt_insert_update:
@@ -3216,12 +3220,12 @@ update:
 	;
 
 update_list:
-	update_list ',' simple_ident equal expr
+	update_list ',' simple_ident equal expr_or_default
 	{
 	  if (add_item_to_list(YYTHD, $3) || add_value_to_list(YYTHD, $5))
 	    YYABORT;
 	}
-	| simple_ident equal expr
+	| simple_ident equal expr_or_default
 	  {
 	    if (add_item_to_list(YYTHD, $1) || add_value_to_list(YYTHD, $3))
 	      YYABORT;

sql/table.h

@@ -137,6 +137,7 @@ struct st_table {
   uint          derived_select_number;   
   THD		*in_use;		/* Which thread uses this */
   struct st_table *next,*prev;
+  byte *default_values() { return record[2]; }
 };