Function update_user_table

phx_percona/percona/sql/sql_acl.cc:2908–2992

*/

static bool
update_user_table(THD *thd, TABLE *table,
                  const char *host, const char *user,
                  const char *new_password, uint new_password_len,
                  enum mysql_user_table_field password_field,
                  bool password_expired, bool is_user_table_positioned)
{
  char user_key[MAX_KEY_LENGTH];
  int error;
  DBUG_ENTER("update_user_table");
  DBUG_PRINT("enter",("user: %s  host: %s",user,host));

  /* ALTER USER PASSWORD EXPIRE makes no sense on old system tables */
  if (table->s->fields <= MYSQL_USER_FIELD_PASSWORD_EXPIRED &&
      password_expired)
  {
    my_error(ER_BAD_FIELD_ERROR, MYF(0), "password_expired", "mysql.user");
    DBUG_RETURN(1);
  }

  /* 
    If this function is reached through change_password, the user record is 
    already available and hence need not be read again.
  */

  if (!is_user_table_positioned)
  {
    table->use_all_columns();
    DBUG_ASSERT(host != '\0');
    table->field[MYSQL_USER_FIELD_HOST]->store(host, (uint) strlen(host),
					       system_charset_info);
    table->field[MYSQL_USER_FIELD_USER]->store(user, (uint) strlen(user),
					       system_charset_info);
    key_copy((uchar *) user_key, table->record[0], table->key_info,
	     table->key_info->key_length);

    if (table->file->ha_index_read_idx_map(table->record[0], 0,
					   (uchar *) user_key, HA_WHOLE_KEY,
					   HA_READ_KEY_EXACT))
    {
      my_message(ER_PASSWORD_NO_MATCH, ER(ER_PASSWORD_NO_MATCH),
		 MYF(0));	/* purecov: deadcode */
      DBUG_RETURN(1);		/* purecov: deadcode */
    }
  }
  store_record(table,record[1]);
 
  /* 
    When the flag is on we're inside ALTER TABLE ... PASSWORD EXPIRE and we 
    have no password to update.
  */
  if (!password_expired)
  {
    if (table->s->fields >= (uint) password_field)
      table->field[(uint) password_field]->store(new_password, new_password_len,
                                                 system_charset_info);
    else
    {