68 lines
2.2 KiB
Text
68 lines
2.2 KiB
Text
|
|
||
|
|
XZ Utils To-Do List
|
||
|
|
===================
|
||
|
|
|
||
|
|
Known bugs
|
||
|
|
----------
|
||
|
|
|
||
|
|
The test suite is too incomplete.
|
||
|
|
|
||
|
|
If the memory usage limit is less than about 13 MiB, xz is unable to
|
||
|
|
automatically scale down the compression settings enough even though
|
||
|
|
it would be possible by switching from BT2/BT3/BT4 match finder to
|
||
|
|
HC3/HC4.
|
||
|
|
|
||
|
|
The code to detect number of CPU cores doesn't count hyperthreading
|
||
|
|
as multiple cores. In context of xz, it probably should.
|
||
|
|
Hyperthreading is good at least with p7zip.
|
||
|
|
|
||
|
|
XZ Utils compress some files significantly worse than LZMA Utils.
|
||
|
|
This is due to faster compression presets used by XZ Utils, and
|
||
|
|
can often be worked around by using "xz --extreme". With some files
|
||
|
|
--extreme isn't enough though: it's most likely with files that
|
||
|
|
compress extremely well, so going from compression ratio of 0.003
|
||
|
|
to 0.004 means big relative increase in the compressed file size.
|
||
|
|
|
||
|
|
xz doesn't quote unprintable characters when it displays file names
|
||
|
|
given on the command line.
|
||
|
|
|
||
|
|
tuklib_exit() doesn't block signals => EINTR is possible.
|
||
|
|
|
||
|
|
SIGTSTP is not handled. If xz is stopped, the estimated remaining
|
||
|
|
time and calculated (de)compression speed won't make sense in the
|
||
|
|
progress indicator (xz --verbose).
|
||
|
|
|
||
|
|
|
||
|
|
Missing features
|
||
|
|
----------------
|
||
|
|
|
||
|
|
xz doesn't support copying extended attributes, access control
|
||
|
|
lists etc. from source to target file.
|
||
|
|
|
||
|
|
Multithreaded compression
|
||
|
|
|
||
|
|
Multithreaded decompression
|
||
|
|
|
||
|
|
Buffer-to-buffer coding could use less RAM (especially when
|
||
|
|
decompressing LZMA1 or LZMA2).
|
||
|
|
|
||
|
|
I/O library is not implemented (similar to gzopen() in zlib).
|
||
|
|
It will be a separate library that supports uncompressed, .gz,
|
||
|
|
.bz2, .lzma, and .xz files.
|
||
|
|
|
||
|
|
lzma_strerror() to convert lzma_ret to human readable form?
|
||
|
|
This is tricky, because the same error codes are used with
|
||
|
|
slightly different meanings, and this cannot be fixed anymore.
|
||
|
|
|
||
|
|
|
||
|
|
Documentation
|
||
|
|
-------------
|
||
|
|
|
||
|
|
Some tutorial is needed for liblzma. I have planned to write some
|
||
|
|
extremely well commented example programs, which would work as
|
||
|
|
a tutorial. I suppose the Doxygen tags are quite OK as a quick
|
||
|
|
reference once one is familiar with the liblzma API.
|
||
|
|
|
||
|
|
Document the LZMA1 and LZMA2 algorithms.
|
||
|
|
|