- Avoids copying std::shared_ptr when lifetime of the RuleMessage
is controlled by the caller.
- The RuleMessage instance is created in RuleWithActions::evaluate and
then used to call the overloaded version of this method that is
specialized by subclasses.
- Once the call to the overloaded method returns, the std::shared_ptr
is destroyed as it's not stored by any of the callers, so it can
be replaced with a stack variable and avoid paying the cost of
copying the std::shared_ptr (and its control block that is
guaranteed to be thread-safe and thus is not a straightforward
pointer copy)
- Introduced RuleMessage::reset because this is required by
RuleWithActions::performLogging when it's not the 'last log', the rule
has multimatch and it's to be logged.
- The current version is creating allocating another instance of
RuleMessage on the heap to copy the Rule & Transaction related state
while all the other members in the RuleMessage are set to their
default values.
- The new version leverages the existent, unused and incomplete
function 'clean' (renamed as 'reset') to do this on the current
instance.
- Notice that the current code preserves the value of m_saveMessage,
so 'reset' provides an argument for the caller to control whether
this member should be reinitialized.
- Renamed Transformation::evaluate to Transformation::transform to avoid
confusion with Action's overload methods.
- Updated Transformation::transform signature to receive the value by
reference and perform the transformation inline, if possible.
- Some transformations still need to use a temporary std::string to
perform their work, and then copy the result back.
- Made Transformation::transform methods const and updated Transaction
parameter to be const.
- Transaction parameter could not be removed because it's used by just
a single transformation, UrlDecodeUni.
- Removed std::string Action::evaluate(const std::string &exp,
Transaction *transaction); which was only implemented by
Transformation but was not used from the base class, but only after
downcasting to Transformation, so it can just be declared there (and
not pollute other actions with a default member implementation -that
does nothing- which is never called).
- The previous approach would create a std::unique_ptr and store it in
a std::list in VariableValue (Origins)
- The new approach now stores Origins in a std::vector and constructs
VariableOrigin elements in-place on insertion.
- Instead of having two heap-allocations for every added VariableOrigin
instance, this performs only one.
- If multiple origins are added, std::vector's growth strategy may even
prevent a heap-allocation. There's a cost on growing the size of the
vector, because a copy of current elements will be necessary.
- Introduced reserveOrigin method to notify that multiple insertions
will be made, so that we can use std::vector's reserve and do a
single allocation (and copy of previous elements), and then just
initialize the new elements in-place.
