xapian-core-1.4.13

[Bruce Dubbs]

New point version.

[Bruce Dubbs]

Xapian-core 1.4.13 (2019-10-14):

API:

• Fix write one past end of std::vector on certain QueryParser parser errors. This is undefined behaviour, but the write was always into reserved space, so in practice we'd actually get away with it (it was noticed because it triggers an error when running under ubsan and using libc++). Reported by Germán M. Bravo.

• MSet::get_matches_estimated(): Improve rounding of result - a bug meant we would almost always round down.

• Optimise test for UTF-8 continuation character. Performing a signed char comparison shaves an instruction or two on most architectures.

• Database::get_revision(): Return revision 0 for a Database with no shards rather that throwing InvalidOperationError.

• DPHWeight: Avoid dividing by 0 when searching a sharded database when one shard is empty. The result wasn't used in this case, but it's still undefined behaviour. Detected by UBSan.

testsuite:

• The "singlefile" test harness backend manager now creates databases by compacting the corresponding underlying backend database (creating it first if need be) rather than always creating a temporary database to compact.

• Enable compaction testcases for multi and singlefile test harness backends.

• Add generated database support for remoteprog and remotetcp test harness backends. Implemented by Tanmay Sachan.

• Add test harness support for running testcases using a multi database comprised of one local and one remote shard, or two remote shards. Implemented by Tanmay Sachan.

• Check if removing existing multi stub failed. Previously if removing an existing stub failed, the test harness would create a temporary new stub and then try to rename it over the old one, which will always fail on Microsoft Windows.

• Wait for xapian-tcpsrv processes to finish before moving on to the next testcase under WIN32 like we already do on POSIX platforms.

matcher:

• Optimise OP_AND_NOT better. We now combine its left argument with other connected and-like subqueries, and gather up and hoist the negated subqueries and apply them together above the combined and-like subqueries, just below any positional filters.

• Optimise OP_AND_MAYBE better. We now combine its left argument with other connected and-like subqueries, and gather up and hoist the optional subqueries and apply them together above the combined and-like subqueries and any hoisted positional filters.

• Treat all BoolWeight queries as scaled by 0 - we can optimise better if we know the query is unweighted.

glass backend:

• Allow zlib compression to reduce size by one byte. We were specifying an output buffer size one byte smaller than the input, but it appears zlib won't use the final byte in the buffer, so we actually need to pass the input size as the output buffer size.

• Only try to compress Btree item values > 18 bytes, which saves CPU time without sacrificing any significant size savings.

remote backend:

• Fix match stats when searching with collapsing over multiple shards and at least some shards are remote. Bug discovered by Tanmay Sachan's test harness improvements.

• Ignore orphaned remote protocol replies which can happen when searching with a remote shard if an exception is thrown by another shard. Bug discovered by Tanmay Sachan's test harness improvements.

• Wait for xapian-progsrv child to exit when a remote Database or WritableDatabase object is closed under WIN32 like we already do for POSIX platforms.

documentation:

• Correct documentation of initial messages in replication protocol.

tools:

• quest: Report bounds and estimate of number of matches.

• xapian-delve: Improve output when database revision information is not available. We now specially handle the cases of a DB with multiple shards and a backend which doesn't support get_revision().

portability:

• Fix warning from GCC 9 with -Wdeprecated-copy (which is enabled by -Wextra) if a reference to an Error object is thrown.

• Suppress GCC warning in our API headers when compiling code using Xapian with GCC and -Wduplicated-branches.

• Mark some internal classes as final (following GCC -Wsuggest-final-types suggestions to allow some method calls to be devirtualised).

• Fix to build with --enable-maintainer-mode and Perl < 5.10, which doesn't have the //= operator. It's unlikely developers will have such an old Perl, but the mingw environment on appveyor CI does. The use of //= was introduced by changes in 1.4.10.

[Bruce Dubbs]

Fixed at revision 22276.