This is a list of notable changes to Hyperscan, in reverse chronological order.
- Introduce an interpreter for many complex actions to replace the use of internal reports within the core of Hyperscan (the "Rose" engine). This improves scanning performance and reduces database size for many pattern sets.
- Many enhancements to the acceleration framework used by NFA and DFA engines, including more flexible multibyte implementations and more AVX2 support. This improves scanning performance for many pattern sets.
- Improved prefiltering support for complex patterns containing very large
bounded repeats (
R{M,N}
with largeN
). - Improve scanning performance of pattern sets with a very large number of EOD-anchored patterns.
- Improve scanning performance of large pattern sets that use the
HS_FLAG_SINGLEMATCH
flag. - Improve scanning performance of pattern sets that contain a single literal by improving the "Noodle" literal matcher.
- Small reductions in total stream state for many pattern sets.
- Improve runtime detection of AVX2 support.
- Disable -Werror for release builds, in order to behave better for packagers and users with different compiler combinations than those that we test.
- Improve support for building on Windows with MSVC 2015 (github issue #14). Support for Hyperscan on Windows is still experimental.
- Small updates to fix warnings identified by Coverity.
- Remove Python codegen for the "FDR" and "Teddy" literal matchers. These are now implemented directly in C code.
- Remove the specialist "Sidecar" engine in favour of using our more general repeat engines.
- New API function: add the
hs_expression_ext_info()
function. This is a variant ofhs_expression_info()
that can accept patterns with extended parameters. - New API error value: add the
HS_SCRATCH_IN_USE
error, which is returned when Hyperscan detects that a scratch region is already in use on entry to an API function.
- Update version of PCRE used by testing tools as a syntax and semantic reference to PCRE 8.38.
- Small updates to fix warnings identified by Coverity.
- Clean up and unify exception handling behaviour across GPR and SIMD NFA models.
- Fix bug in handling of bounded repeat triggers with large gaps between them for sparse repeat model.
- Correctly reject POSIX collating elements (
[.ch.]
,[=ch=]
) in the parser. These are not supported by Hyperscan. - Add support for quoted sequences (
\Q...\E
) inside character classes. - Simplify FDR literal matcher runtime by removing some static specialization.
- Fix handling of the POSIX
[:graph:]
,[:print:]
and[:punct:]
character classes to match the behaviour of PCRE 8.38 in both standard operation and with the UCP flag set. (Note: some bugs were fixed in this area in PCRE 8.38.) Previously Hyperscan's behaviour was the same as versions of PCRE before 8.34. - Improve performance when compiling pattern sets that include a large number of similar bounded repeat constructs. (github issue #9)
- Minor cleanups to test code.
- CMake and other build system improvements.
- API update: allow
hs_reset_stream()
andhs_reset_and_copy_stream()
to be supplied with a NULL scratch pointer if no matches are required. This is in line with the behaviour ofhs_close_stream()
. - Disallow bounded repeats with a very large minimum repeat but no maximum, i.e. {N,} for very large N.
- Reduce compile memory usage in literal set explansion for some large cases.
- Original release of Hyperscan as open-source software.