Ilya Tokar [Wed, 23 Feb 2022 22:59:56 +0000 (17:59 -0500)]
Use helper function for bit manipulations.
We already have BIT_getLowerBits, so use it. Benefits are 2fold:
1) Somewhat cleaner code
2) We are now using bzhi instructions, when available. Performance
delta is too small for microbenchmarks, but avoiding load still helps
larger applications, by reducing data cache pressure.
Nick Terrell [Mon, 7 Feb 2022 23:20:42 +0000 (15:20 -0800)]
[cli-tests] Fix zstd symlinks
The zstd symlinks, notably `zstdcat`, weren't working as expected
because only the `tests/cli-tests/bin/zstd` wrapper was symlinked. We
still invoked `zstd` with the name `zstd`. The fix is to create a
directory of zstd symlinks in `tests/cli-tests/bin/symlinks` for each
name that zstd recognizes. And when `tets/cli-tests/bin/zstd` is
invoked, it selects the correct symlink to call.
See the test `zstd-cli/zstdcat.sh` for an example of how it would work.
* playtests.sh: fix for a bug in macos' /bin/sh that persists temporary env vars when introduced before function calls
* cli-tests/run.py: Do not use existing ZSTD* envvars
Fix required decompression memory usage reported by -vv + --long
The use of --long alters the window size internally in the underlying
library (lib/compress/zstd_compress.c:ZSTD_getCParamsFromCCtxParams),
which changes the memory required for decompression. This means that the
reported requirement from the zstd binary when -vv is specified is
incorrect.
A full fix for this would be to add an API call to be able to retrieve
the required decompression memory from the library, but as a
lighterweight fix we can just take account of the fact we've enabled
long mode and update our verbose output appropriately.
Yann Collet [Mon, 31 Jan 2022 17:34:04 +0000 (09:34 -0800)]
fix 44239
credit to oss-fuzz
This issue could happen when using the new Sequence Compression API in Explicit Delimiter Mode
with a too small dstCapacity.
In which case, there was one place where the buffer size wasn't checked.
Nick Terrell [Sun, 30 Jan 2022 20:16:16 +0000 (12:16 -0800)]
Fix static analysis false-positives
* It couldn't detect that the `fastCoverParams` can't be non-null, since it was just an assertion.
* It thought we were accesing `wksp->dtable` beyond the bounds because we were using it to set the `workSpace` value. Instead, compute the workspace size used in a different way.
Yann Collet [Sun, 30 Jan 2022 00:23:21 +0000 (16:23 -0800)]
fixed bug 44168
discovered by oss-fuzz
It's a bug in the test itself :
ZSTD_compressBound() as an upper bound of the compress size
only works for data compressed "normally".
But in situations where many flushes are forcefully introduced,
this creates many more blocks,
each of which has a potential to increase the size by 3 bytes.
In extreme cases (lots of small incompressible blocks), the expansion can go beyond ZSTD_compressBound().
This situation is similar when using the CompressSequences() API
with Explicit Block Delimiters.
In which case, each explicit block acts like a deliberate flush.
When employed by a fuzzer, it's possible to generate scenarios like the one described above,
with tons of incompressible blocks of small sizes,
thus going beyond ZSTD_compressBound().
fix : when using Explicit Block Delimiters, use a larger bound, to account for this scenario.
Nick Terrell [Mon, 24 Jan 2022 21:52:08 +0000 (13:52 -0800)]
[CI] Hook cli-tests up to CI
Add cli-tests to `make test`. This adds a `python3` dependency to `make
test`, but not `make check`. We could make this dependency optional by
skipping the tests if `python3` is not present.
Nick Terrell [Fri, 21 Jan 2022 06:45:03 +0000 (22:45 -0800)]
[zstdcli] Fix option detection for --auto-threads
The option `--auto-threads` should still be accepted and parsed, even if
`ZSTD_MULTITHREAD` is not defined. It doesn't mean anything, but we
should still accept the option. Since we want scripts to be able to work
generically.
This bug was caught by tests I added to the new testing framework.
Yann Collet [Thu, 27 Jan 2022 13:13:45 +0000 (05:13 -0800)]
fix issue 44108
credit to oss-fuzz
In rare circumstances, the block-splitter might cut a block at the exact beginning of a repcode.
In which case, since litlength=0, if the repcode expected 1+ literals in front, its signification changes.
This scenario is controlled in ZSTD_seqStore_resolveOffCodes(),
and the repcode is transformed into a raw offset when its new meaning is incorrect.
In more complex scenarios, the previous block might be emitted as uncompressed after all,
thus modifying the expected repcode history.
In the case discovered by oss-fuzz, the first block is emitted as uncompressed,
so the repcode history remains at default values: 1,4,8.
But since the starting repcode is repcode3, and the literal length is == 0,
its meaning is : = repcode1 - 1.
Since repcode1==1, it results in an offset value of 0, which is invalid.
So that's what the `assert()` was verifying : the result of the repcode translation should be a valid offset.
But actually, it doesn't matter, because this result will then be compared to reality,
and since it's an invalid offset, it will necessarily be discarded if incorrect,
then the repcode will be replaced by a raw offset.
So the `assert()` is not useful.
Furthermore, it's incorrect, because it assumes this situation cannot happen, but it does, as described in above scenario.
Nick Terrell [Thu, 27 Jan 2022 01:55:26 +0000 (17:55 -0800)]
Print zlib/lz4/lzma library versions in verbose version output
Knowing the version of zlib/lz4/lzma we're linking against is very
useful for debugging issues with those libraries, so print it out in the
verbosity 4 version output.
Also print this information at the top of `playTests.sh`.
Yann Collet [Fri, 21 Jan 2022 05:24:33 +0000 (21:24 -0800)]
improved compression of literals in specific corner cases
In rare cases, the default huffman depth selector is a bit too harsh,
requiring brutal adaptations to the tree,
resulting is some loss of compression ratio.
This new heuristic avoids the worse cases, favoring compression ratio.
As an example, compression of a specific distribution of 771 literals
is now improved to 441 bytes, from 601 bytes before.
brailovich [Tue, 25 Jan 2022 01:42:21 +0000 (17:42 -0800)]
fix for error message in recursive mode for an empty folder
-r on empty directory resulted in zstd waiting input from stdin. now zstd exits without error and prints a warning message explaining why no processing happened (no files or directories to process).
Yonatan Komornik [Mon, 24 Jan 2022 22:43:02 +0000 (14:43 -0800)]
AsyncIO compression part 1 - refactor of existing asyncio code (#3021)
* Refactored fileio.c:
- Extracted asyncio code to fileio_asyncio.c/.h
- Moved type definitions to fileio_types.h
- Moved common macro definitions needed by both fileio.c and fileio_asyncio.c to fileio_common.h
Yonatan Komornik [Fri, 21 Jan 2022 21:55:41 +0000 (13:55 -0800)]
Async write for decompression (#2975)
* Async IO decompression:
- Added --[no-]asyncio flag for CLI decompression.
- Replaced dstBuffer in decompression with a pool of write jobs.
- Added an ability to execute write jobs in a separate thread.
- Added an ability to wait (join) on all jobs in a thread pool (queued and running).
projects / thirdparty / zstd.git / log
