diff options
Diffstat (limited to 'sql/item_strfunc.h')
| -rw-r--r-- | sql/item_strfunc.h | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/sql/item_strfunc.h b/sql/item_strfunc.h index 0a6375e80a5..8974feb10fa 100644 --- a/sql/item_strfunc.h +++ b/sql/item_strfunc.h @@ -22,6 +22,23 @@ class Item_str_func :public Item_func { +protected: + /** + Sets the result value of the function an empty string, using the current + character set. No memory is allocated. + @retval A pointer to the str_value member. + */ + String *make_empty_result() + { + /* + Reset string length to an empty string. We don't use str_value.set() as + we don't want to free and potentially have to reallocate the buffer + for each call. + */ + str_value.length(0); + str_value.set_charset(collation.collation); + return &str_value; + } public: Item_str_func() :Item_func() { decimals=NOT_FIXED_DEC; } Item_str_func(Item *a) :Item_func(a) {decimals=NOT_FIXED_DEC; } @@ -694,15 +711,17 @@ public: String *val_str(String *); void fix_length_and_dec() { - ulonglong max_result_length= (ulonglong) args[0]->max_length * 2 + 2; - max_length= (uint32) min(max_result_length, MAX_BLOB_WIDTH); collation.set(args[0]->collation); + ulonglong max_result_length= (ulonglong) args[0]->max_length * 2 + + 2 * collation.collation->mbmaxlen; + max_length= (uint32) min(max_result_length, MAX_BLOB_WIDTH); } }; class Item_func_conv_charset :public Item_str_func { bool use_cached_value; + String tmp_value; public: bool safe; CHARSET_INFO *conv_charset; // keep it public |