Everything converge towards ZSTD_compressBegin_internal
which delegated to ZSTD_copyCCtx_internal if cdict!=NULL.
This simplifies routing which was previously depending on cdict.
The following warning appears during build.
../lib/compress/huf_compress.c: In function ‘HUF_compress1X_usingCTable’:
../lib/compress/huf_compress.c:444:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (sizeof((stream)->bitContainer)*8 < HUF_TABLELOG_MAX*4+7) HUF_FLUSHBITS(stream)
^
../lib/compress/huf_compress.c:465:18: note: in expansion of macro ‘HUF_FLUSHBITS_2’
HUF_FLUSHBITS_2(&bitC);
^~~~~~~~~~~~~~~
../lib/compress/huf_compress.c:466:9: note: here
case 2 : HUF_encodeSymbol(&bitC, ip[n+ 1], CTable);
../lib/compress/zstd_compress.c: In function ‘ZSTD_compressStream_generic’:
../lib/compress/zstd_compress.c:3366:34: warning: this statement may fall through [-Wimplicit-fallthrough=]
zcs->streamStage = zcss_flush; /* pass-through to flush stage */
~~~~~~~~~~~~~~~~~^~~~~~~~~~~~
../lib/compress/zstd_compress.c:3369:9: note: here
case zcss_flush:
Signed-off-by: Jos Collin <jcollin@redhat.com>
* upstream/dev: (305 commits)
added test for ZSTD_estimateCStreamSize()
changed variable name, for clarity
fixed ZSTD_estimateCStreamSize()
shortened ZSTD_createCStream_Advanced()
fixed symbols test
added ZSTD_estimateDStreamSize()
changed name frameParams into frameHeader
regroup memory usage function declarations
separated ZSTD_estimateCStreamSize() from ZSTD_estimateCCtxSize()
bumped version number
added ZSTD_estimateCDictSize() and ZSTD_estimateDDictSize()
Updated ZSTD_freeCCtx()
updated ZSTD_estimateCCtxSize()
Updated ZSTD_sizeof_CCtx()
merged CCtx and CStream as a single same object
cli : -d and -t do not stop after a failed decompression
added dev branch CircleCI badge
added dev branch Appveyor badge
keep dev branch status only
creates a binary archive without the `programs` directory
...
added a parameter streaming,
to estimate memory allocation size
when the CCtx is used for streaming (CStream).
Note : this function is not able to estimate
memory cost of a potential internal CDict
which can only happen when starting with ZSTD_initCStream_usingDict()
Previous -18 : 4.7 MB/s, R:3.833
New -18 : 5.1 MB/s. R:3.825
It's a better fit within -17 (6.8 MB/s) and -19 (4.0 MB/s)
The new level 18 also uses significantly less memory.
And, it makes a good transition between level 17 (mml5)
and level 19 (mml3).
Up to now, there was no level with mml4.
(note : minmatch setting can have a large impact on some (specific) datasets)
It now only uses compressionParameters as argument.
It produces many changes throughout user code,
though hopefully they tend to be simple :
just provide the cParams part from existing ZSTD_parameters.
Some programs might depend on ZSTD_createCDict_advanced() to pass frame parameters.
This change will force them to revisit this strategy and fix it,
since frame parameters are effectively silently ignored in current version.
clearer separation between variables and buffers
clearer buffers category
kept static buffers at the beginning, favoring cache locality
(it will be easier to add FSE tables there later)
This break a few assumptions that hashTable was always at the beginning.
This is fixed.
And remaining assumptions (namely that tables stand next to each other in memory)
are now tested with assert.
because by definition srcSize is not known when using this prototype.
added relevant test
Note : this use was already working, because at a later stage
(both ZSTD_compressBegin_usingCDict() and ZSTD_copyCCtx())
pledgedSrcSize=0 is translated into "unknown", no matter the frame parameter.
This is not correct, but of little importance,
as the medium term plan is to no longer set fParams within CDict
This is now the regroup point for ZSTD_initCStream*() functions
ZSTD_initCStream_advanced() now properly checks for parameters validity.
Also : added <assert.h> usage inside zstd_compress.c
Needs ZSTD_DEBUG=1 macro to be triggered.
Will be triggered by default from `tests` directory
does no longer allocate temporary buffers
when there is enough room in dstBuffer to decompress directly there.
(previous method would skip that for 1st chunk only).
Also : fix ZSTD_compressBound() for small srcSize
required so that if Total = A+B
compressBound(Total) <= compressBound(A) + compressBound(B)
under condition of a minimum size for A and B
Will help for ZSTDMT_compress() memory allocation
forgot to add the dictionary content
(tests were not failing, just compressing less).
Also : added size protections when adding dict content
since hc/bt table filling would fail if size < 8
The compressor always reuses the existing Huffman table if the literals
size is at most 1 KiB. If the compression strategy is `ZSTD_lazy` or
stronger always check to see if reusing the previous table or creating
a new table is better.
This doesn't yet weigh in decompression speed. I don't want to add any
heuristics there until I have real data to work with to ensure that the
heuristic works for at least one use case, preferably more.
