1
0
mirror of https://github.com/MariaDB/server.git synced 2025-07-27 18:02:13 +03:00

Fix for BUG#7716: in in_string::set() take into account that the value returned

by item->val_str() may be a substring of the passed string. 
Disallow string=its_substring assignment in String::operator=().


mysql-test/r/func_misc.result:
  Testcase for BUG#7716
mysql-test/t/func_misc.test:
  Testcase for BUG#7716
sql/item_cmpfunc.cc:
  Fix for BUG#7716: in in_string::set() take into account that the string returned 
  by item->val_str(S) may be not S but use the buffer owned by S.
sql/sql_string.h:
  * Added assert: String& String::operator=(const String&) may not be used to do 
    assignments like str = string_that_uses_buffer_owned_by_str
  * Added String::uses_buffer_owned_by().
This commit is contained in:
unknown
2005-02-04 09:14:22 +03:00
parent bd556f0d70
commit ebda548d0d
4 changed files with 50 additions and 0 deletions

View File

@ -182,6 +182,11 @@ public:
{
if (&s != this)
{
/*
It is forbidden to do assignments like
some_string = substring_of_that_string
*/
DBUG_ASSERT(!s.uses_buffer_owned_by(this));
free();
Ptr=s.Ptr ; str_length=s.str_length ; Alloced_length=s.Alloced_length;
alloced=0;
@ -313,4 +318,9 @@ public:
/* Swap two string objects. Efficient way to exchange data without memcpy. */
void swap(String &s);
inline bool uses_buffer_owned_by(const String *s) const
{
return (s->alloced && Ptr >= s->Ptr && Ptr < s->Ptr + s->str_length);
}
};