Add the kernel wrapper API. This keeps the same API and semantics as the
existing kernel API with name changes to be more kernel style and avoid
symbol collisions with zstd.
https://github.com/facebook/zstd/pull/2339 removes the single-pass zstdmt API.
This changes the compressed size, because we no longer take the # of threads into
account when deciding the job size.
We don't use it when we have a stable input buffer, so don't allocate
it. I had to slightly modify `ZSTD_copyCCtx()` by storing the
`ZSTD_buffered_policy_e` in the `ZSTD_CCtx`, since `inBuffSize > 0` is
no longer the correct signal for the buffered mode.
When we have a stable output buffer take the single-pass shortcut.
It is okay to return `dstSizeTooSmall` if the output buffer isn't
big enough, because we know it will never grow.
Sets these parameters in ZSTD_compress2() then resets them to their
orignal values after the compression call.
An alternative design could be to add a flush mode `ZSTD_e_singlePass`
which implies `ZSTD_c_stable{In,Out}Buffer` but only for a single
compression call, by directly setting the applied parameters. I've opted
for the smaller change, but this is open for discussion.
Previously only `nbWorkers` was set. Set all parameters, because that is
what is expected. This is needed for the `ZSTD_c_stable{In,Out}Buffer`
parameters.
The problem occurs in this scenario:
1. We find a synchronization point.
2. We attmept to create the job.
3. We fail because the job table is full: `mtctx->nextJobID > mtctx->doneJobID + mtctx->jobIDMask`.
4. We call `ZSTDMT_compressStream_generic` again.
5. We forget that we're at a sync point already, and we continue looking
for the next sync point.
This fix is to detect if we're currently paused at a sync point, and if
we are then don't load any more input.
Caught by zstreamtest. I modified it to make the bug occur more often
(~1/100K -> ~1/200) and verified that it is fixed after. I then ran a
few hundred thousand unmodified zstreamtest iterations to verify.
When zstdmt cannot get a buffer and `ZSTD_e_end` is passed an empty
compression job can be created. Additionally, `mtctx->frameEnded` can be
set to 1, which could potentially cause problems like unterminated blocks.
The fix is to adjust to `ZSTD_e_flush` even when we can't get a buffer.
* Run compression twice and check the compressed data is byte-identical.
The compression loop had to be rewritten to ensure deteriminism. It is
guaranteed by always making maximal forward progress.
* When nbWorkers > 0, change the number of workers 1/8 of the time.
* Run in single-pass mode 1/4 of the time.
I've run a few hundred thousand iterations of zstreamtest and have seen
no deteriminism issues so far. Before the zstdmt fix that skips the
single-pass shortcut non-determinism showed up in a few hundred
iterations.
This commit leaves only the functions used by zstd_compress.c. All other
functions have been removed from the API. The ZSTDMT unit tests in
fuzzer.c and zstreamtest.c have been rewritten to use the ZSTD API. And
the --mt zstreamtest tests have been ripped out.
Simplifies the code and removes blocking from zstdmt.
At this point we could completely delete
`ZSTDMT_compress_advanced_internal()`. However I'm leaving it in because
I think we want to do that in the zstd-1.5.0 release, in case anyone is
still using the ZSTDMT API, even though it is not installed by default.
Fixes#2327.
Pass in the `ZSTD_cParamMode_e` to select how we define our cparams.
Based on the mode we either take the `dictSize` into account or we set
it to `0`. See the documentation for `ZSTD_cParamMode_e`.
Some of the modes currently share the same behavior. But they have
distinct modes because they are drastically different cases. E.g.
compression + reprocessing the dictionary and creating a cdict.
Additionally, when downsizing the hashLog and chainLog take the
(adjusted) dictionary size into account, since the size of the
dictionary gets added onto the window size.
Adds a simple test to ensure that we aren't downsizing too far.
The DDS structure can't be copied into the working tables like the DMS.
So it doesn't need to account for the source size when sizing its
parameters, just the dictionary size.
Conditions to trigger:
* CDict is loaded as raw content.
* CDict starts with the zstd dictionary magic number.
* The CDict is reprocessed (not attached or copied).
* The new API is used (streaming or `ZSTD_compress2()`).
Bug: The dictionary is loaded as a zstd dictionary, not a raw content
dictionary, because the dict content type is set to `ZSTD_dct_auto`.
Fix: Pass in the dictionary content type from cdict creation to the call
to `ZSTD_compress_insertDictionary()`.
Test: Added a test case that exposes the bug, and fixed the raw
content tests to not modify the `dictBuffer`, which makes all future
tests with the `dictBuffer` raw content, which doesn't seem intentional.
Rename ADDRESS_SANITIZER -> ZSTD_ADDRESS_SANITIZER and same for
MEMORY_SANITIZER. Also set it to 0/1 instead of checking for defined.
This allows the user to override ASAN/MSAN detection for platforms that
don't support it.
This clarifies operator precedence, and quiets cppcheck in
the Kernel Test Robot. I think this is a slight bonus to
readability, so I am accepting the suggestion.
Add decompress_sources.h, which includes all the decompression .c files.
This is used for kernel decompression.
Also, add a test which checks that including decompress_sources.h works.
The unused function definitions are hidden behind a
`#ifndef ZSTD_NO_UNUSED_FUNCTIONS` check.
Initially hiding all functions which are unused and take up more than
2KB of stack space, because these will show up as warnings in the
Linux Kernel build system.
