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.
* 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
* Bugfix - rename fileio_asycio to fileio_asyncio
* Added copyrights & license to new files
* CR fixes
* 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).
We previously triggered release artifact generation on release creation. We
sometimes observed that the action failed to run. I hypothesized that we were
hitting rate limiting or something. I just stumbled across [this documentat-
ion](https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#release), which says:
> Note: Workflows are not triggered for the `created`, `edited`, or `deleted`
> activity types for draft releases. When you create your release through the
> GitHub browser UI, your release may automatically be saved as a draft.
This must have been what was happening. This commit therefore changes the
trigger to the `published` activity. This should be more reliable.
This does have the unfortunate side effect that artifacts won't be generated
or attached until *after* the release has been published, which is what I was
trying to avoid by using the `created` activity. Oh well.
Append -z cet-report=error to LDFLAGS if -fcf-protection is enabled by
default in compiler to catch the missing Intel CET marker:
compiling multi-threaded dynamic library 1.5.1
/usr/local/bin/ld: obj/conf_f408b4c825de923ffc88f7f21b6884b1/dynamic/huf_decompress_amd64.o: error: missing IBT and SHSTK properties
collect2: error: ld returned 1 exit status
...
LINK obj/conf_dbc0b41e36c44111bb0bb918e093d7c1/zstd
/usr/local/bin/ld: obj/conf_dbc0b41e36c44111bb0bb918e093d7c1/huf_decompress_amd64.o: error: missing IBT and SHSTK properties
collect2: error: ld returned 1 exit status
When testing amalgamating other projects it was found: invalid Unicode errors were tripping Python's text IO, and the header search order appears differs from the shell version.
Intel Control-flow Enforcement Technology (CET):
https://en.wikipedia.org/wiki/Control-flow_integrity#Intel_Control-flow_Enforcement_Technology
requires that on Linux, all linker input files are marked as CET enabled
in .note.gnu.property section. For high-level language source codes,
.note.gnu.property section is added by compiler with the -fcf-protection
option. For assembly sources, include <cet.h> to add .note.gnu.property
section.