Add a clone() method that can be overridden by subclasses. This allows
copying compile state when needed in a way that preserves
polymorphism.
Signed-off-by: Mark Stemm <mark.stemm@gmail.com>
In order to support external rules loaders that may extend the falco
rules format with new top level objects, move away from providing
individual filter objects to the filter_ruleset via calls to add().
Instead, pass the entire compile output returned by the compiler to
the ruleset using a new method add_compile_output(). Custom users can
then cast back the compile output to the appropriate derived class for
use in the ruleset.
Move the declaration of the compile output to a standalone class so it
can be used by rulesets without including the entire rules loader
header files, and add a new factory method new_compile_output() to the
compiler so it can create a derived class if necessary.
This change is
backwards-compatible with existing rulesets, as the default
implementation of add_compile_output() simply iterates over rules and
calls add() for each rule.
This change also speeds up rule loading. Previously, each rule
condition was compiled twice:
1. First, in the compiler, to see if it was valid.
2. Second, in the falco engine before providing each rule to the
ruleset.
Add the compiled filter to the falco_rule object instead of throwing
it away in the compiler.
Signed-off-by: Mark Stemm <mark.stemm@gmail.com>
