By avoiding to use `broker::data` directly, we gain a degree of freedom
that allows us to swap out `broker::data` for something else (e.g.,
`broker::variant`) in the future. Furthermore, it also helps us to keep
Broker types "local" to the Broker manager and gives us a nicer
interface.
Also replaces uses of `broker::expected` with `std::optional`. While an
`expected `can carry additional information as to why a value is not
present, nothing in Zeek ever cared about that. Hence, using
`std::optional` removes an unnecessary dependency on a Broker detail
while also being more efficient (no extra heap allocation when no value
is present).
This largely copies over Spicy's `.clang-format` configuration file. The
one place where we deviate is header include order since Zeek depends on
headers being included in a certain order.
This commit moves some of the hash datastructures and code from
util.cc into Hash.cc - where it seems more appropriate.
It also starts to make more Keyed hash functions available - still
using siphash as the default 64 bit keyed hash, but also making
128 and 256 bit highway hashes available.
There already are a few other functions that are defined but not
yet implemented - these will be "static" keyed hashes - which use
an installation specific key. These will be used to, e.g., get
rid of md5 hashing for the generation of file UIDs.
Currently, siphash is used for strings up to 36 bytes. hmac-md5 is used
for longer strings.
This switch-over is a remnant of the previous hash-function that was
used, which apparently was slower with longer input strings.
This change serves no purpose anymore. I performed a few performance tests
on strings of varying sizes:
For a 40 byte string with 10 million iterations:
siphash: 0.31 seconds
hmac-md5: 3.8 seconds
For a 1080 byte string with 10 million iterations:
siphash: 4.2 seconds
hmac-md5: 17 seconds
For a 18360 byte string with 10 million iterations:
siphash: 69 seconds
hmac-md5: 240 seconds
Hence, this commit removes the use of hmac-md5.
This change causes reordering of lines in a few logs.
This commit also changes the datastructure for the seed in probabilistic/Hasher
to get rid of a type-punning warning.
The Zeek code base has very inconsistent #includes. Many sources
included a few headers, and those headers included other headers, and
in the end, nearly everything is included everywhere, so missing
#includes were never noticed. Another side effect was a lot of header
bloat which slows down the build.
First step to fix it: in each source file, its own header should be
included first to verify that each header's includes are correct, and
none is missing.
After adding the missing #includes, I replaced lots of #includes
inside headers with class forward declarations. In most headers,
object pointers are never referenced, so declaring the function
prototypes with forward-declared classes is just fine.
This patch speeds up the build by 19%, because each compilation unit
gets smaller. Here are the "time" numbers for a fresh build (with a
warm page cache but without ccache):
Before this patch:
3144.94user 161.63system 3:02.87elapsed 1808%CPU (0avgtext+0avgdata 2168608maxresident)k
760inputs+12008400outputs (1511major+57747204minor)pagefaults 0swaps
After this patch:
2565.17user 141.83system 2:25.46elapsed 1860%CPU (0avgtext+0avgdata 1489076maxresident)k
72576inputs+9130920outputs (1667major+49400430minor)pagefaults 0swaps
We need this to sender through Broker, and we also leverage it for
cloning opaques. The serialization methods now produce Broker data
instances directly, and no longer go through the binary formatter.
Summary of the new API for types derived from OpaqueVal:
- Add DECLARE_OPAQUE_VALUE(<class>) to the class declaration
- Add IMPLEMENT_OPAQUE_VALUE(<class>) to the class' implementation file
- Implement these two methods (which are declated by the 1st macro):
- broker::data DoSerialize() const
- bool DoUnserialize(const broker::data& data)
This machinery should work correctly from dynamic plugins as well.
OpaqueVal provides a default implementation of DoClone() as well that
goes through serialization. Derived classes can provide a more
efficient version if they want.
The declaration of the "OpaqueVal" class has moved into the header
file "OpaqueVal.h", along with the new serialization infrastructure.
This is breaking existing code that relies on the location, but
because the API is changing anyways that seems fine.
This adds an internal BiF
"Broker::__opaque_clone_through_serialization" that does what the name
says: deep-copying an opaque by serializing, then-deserializing. That
can be used to tests the new functionality from btests.
Not quite done yet. TODO:
- Not all tests pass yet:
[ 0%] language.named-set-ctors ... failed
[ 16%] language.copy-all-opaques ... failed
[ 33%] language.set-type-checking ... failed
[ 50%] language.table-init-container-ctors ... failed
[ 66%] coverage.sphinx-zeekygen-docs ... failed
[ 83%] scripts.base.frameworks.sumstats.basic-cluster ... failed
(Some of the serialization may still be buggy.)
- Clean up the code a bit more.
Note - this compiles, but you cannot run Bro anymore - it crashes
immediately with a 0-pointer access. The reason behind it is that the
required clone functionality does not work anymore.
This commit marks (hopefully) ever one-parameter constructor as explicit.
It also uses override in (hopefully) all circumstances where a virtual
method is overridden.
There are a very few other minor changes - most of them were necessary
to get everything to compile (like one additional constructor). In one
case I changed an implicit operation to an explicit string conversion -
I think the automatically chosen conversion was much more convoluted.
This took longer than I want to admit but not as long as I feared :)
CompositeHash.
We do this by hashing values added to a BloomFilter another time more
with a stable hash seeded only by either the filter's name or the
global_hash_seed (or Bro's random() seed if neither is defined).
I'm also adding a new bif bloomfilter_internal_state() that returns a
string representation of a Bloom filter's current internal state. This
is solely for writing tests that check that the filters end up
consistent when seeded with the same value.
This commit adds support for script-level specification of a seed to be used by
hashers. For example, if the given name of a Bloom filter is not empty, then
the seed used by the underlying hasher only depends on the Bloom filter name.
If the name is empty, we check whether the user defined a non-empty
global_hash_seed string variable at script and use it instead. If that script
variable does not exist, then we fall back to the initial seed computed a
Bro startup (which is affected ultimately by $BRO_SEED).
See Hasher::MakeSeed for details.
I'm moving the new files into a subdirectory probabilistic, and into a
corresponding namespace. We can later put code for the other
probabilistic data structures there as well.
* origin/topic/matthias/bloom-filter: (45 commits)
Implement and test Bloom filter merging.
Make hash functions equality comparable.
Make counter vectors mergeable.
Use half adder for bitwise addition and subtraction.
Fix and test counting Bloom filter.
Implement missing CounterVector functions.
Tweak hasher interface.
Add missing include for GCC.
Fixing for unserializion error.
Small fixes and style tweaks.
Only serialize Bloom filter type if available.
Create hash policies through factory.
Remove lingering debug code.
Factor implementation and change interface.
Expose Bro's linear congruence PRNG as utility function.
H3 does not check for zero length input.
Support seeding for hashers.
Add utility function to access first random seed.
Update H3 documentation (and minor style nits.)
Make H3 seed configurable.
...
