Preparing the CAST(..AS [UN]SIGNED) related code to fix a number

of bugs easier (MDEV-8919, MDEV-10304, MDEV-10305, MDEV-10307)

- Adding Item::push_note_converted_to_negative_complement() and
  Item::push_note_converted_to_positive_complement()
- Adding virtual methods Item::val_int_signed_typecast() and
  Item::val_int_unsigned_typecast()
- Moving COLUMN_GET() related code from
  Item_func_signed::val_int() and Item_func_unsigned::val_int() to
  Item_dyncol_get::val_int_signed_typecast() and
  Item_dyncol_get::val_int_unsigned_typecast()
- Moving Item_func_signed::val_int_from_str() to Item::val_int_from_str()
  and changing it to get the value from "this" instead of args[0].

The patch does not change behaviour. It's only to simplify fixing of the
mentioned bugs. It will also simplify switching the CAST related code to
use the type handler infrastructure easier (soon).

1 files changed, 16 insertions, 0 deletions

diff --git a/sql/item_strfunc.h b/sql/item_strfunc.h
index 0ff38157c25..72cdf06adde 100644
--- a/sql/item_strfunc.h
+++ b/sql/item_strfunc.h
@@ -1254,6 +1254,22 @@ public:
   const char *func_name() const { return "column_get"; }
   String *val_str(String *);
   longlong val_int();
+  longlong val_int_signed_typecast()
+  {
+    unsigned_flag= false;   // Mark that we want to have a signed value
+    longlong value= val_int(); // val_int() can change unsigned_flag
+    if (!null_value && unsigned_flag && value < 0)
+      push_note_converted_to_negative_complement(current_thd);
+    return value;
+  }
+  longlong val_int_unsigned_typecast()
+  {
+    unsigned_flag= true; // Mark that we want to have an unsigned value
+    longlong value= val_int(); // val_int() can change unsigned_flag
+    if (!null_value && unsigned_flag == 0 && value < 0)
+      push_note_converted_to_positive_complement(current_thd);
+    return value;
+  }
   double val_real();
   my_decimal *val_decimal(my_decimal *);
   bool get_dyn_value(THD *thd, DYNAMIC_COLUMN_VALUE *val, String *tmp);