This should reduce the cases where --extreme makes
compression worse. On the other hand, some other
files may now benefit slightly less from --extreme.
It was 8 + nice_len / 4, now it is 4 + nice_len / 4.
This allows faster settings at lower nice_len values,
even though it seems that I won't use automatic depth
calcuation with HC3 and HC4 in the presets.
For several people, the limiter causes bigger problems that
it solves, so it is better to have it disabled by default.
Those who want to have a limiter by default need to enable
it via the environment variable XZ_DEFAULTS.
Support for environment variable XZ_DEFAULTS was added. It is
parsed before XZ_OPT and technically identical with it. The
intended uses differ quite a bit though; see the man page.
The memory usage limit can now be set separately for
compression and decompression using --memlimit-compress and
--memlimit-decompress. To set both at once, -M or --memlimit
can be used. --memory was retained as a legacy alias for
--memlimit for backwards compatibility.
The semantics of --info-memory were changed in backwards
incompatible way. Compatibility wasn't meaningful due to
changes in the memory usage limiter functionality.
The memory usage limiter info is no longer shown at the
bottom of xz --long -help.
The memory usage limiter support for removed completely from xzdec.
xz's man page was updated to match the above changes. Various
unrelated fixes were also made to the man page.
When using -O2 with GCC, it liked to swap two comparisons
in one "if" statement. It's otherwise fine except that
the latter part, which is seemingly never executed, got
executed (nothing wrong with that) and then triggered
warning in Valgrind about conditional jump depending on
uninitialized variable. A few people find this annoying
so do things a bit differently to avoid the warning.
message_filters_to_str() converts the filter chain to
a string. message_filters_show() replaces the original
message_filters().
uint32_to_optstr() was also added to show the dictionary
size in nicer format when possible.
Don't use #error to generate compile error, because some
compilers actually don't take it as an error. This fixes
tuklib_physmem on IRIX.
Fix incorrect error check for sysconf() return values.
Add AIX, HP-UX, and Tru64 specific code to detect the
amount RAM.
Add HP-UX specific code to detect the number of CPU cores.
Thanks a lot to Peter O'Gorman for initial patches,
testing, and debugging these fixes.
The extra space for showing both has been taken from the
sizes field. If the sizes grow big, bigger units than MiB
will be used. It makes it slightly difficult to see that
progress is still happening with huge files, but it should
be OK in practice.
Thanks to Trent W. Buck for <http://bugs.debian.org/574583>
and Jonathan Nieder for suggestions how to fix it.
Originally both base-2 and base-10 were supported, but since
there seems to be little need for base-10 in XZ Utils, treat
everything as base-2 and also be more relaxed about the case
of the first letter of the suffix. Now xz will accept e.g.
KiB, Ki, k, K, kB, and KB, and interpret them all as 1024. The
recommended spelling of the suffixes are still KiB, MiB, and GiB.
It still feels a bit wrong to round 1 byte to 1 MiB but
at least it is now done consistently so that the same
byte value is always rounded the same way to MiB.
Previously the default limit was always 40 % of RAM. The
new limit is a little bit more complex:
- If 40 % of RAM is at least 80 MiB, 40 % of RAM is used
as the limit.
- If 80 % of RAM is over 80 MiB, 80 MiB is used as the limit.
- Otherwise 80 % of RAM is used as the limit.
This should make it possible to decompress files created with
"xz -9" on more systems. Swapping is generally more expected
on systems with less RAM, so higher default limit on them
shouldn't cause too bad surprises in terms of heavy swapping.
Instead, the higher default limit should reduce the number of
bad surprises when it used to prevent decompression of files
created with "xz -9". The DoS prevention system shouldn't be
a DoS itself.
Note that even with the new default limit, a system with 64 MiB
RAM cannot decompress files created with "xz -9" without user
overriding the limit. This should be OK, because if xz is going
to need more memory than the system has RAM, it will run very
very slowly and thus it's good that user has to override the limit
in that case.
With bad luck, lzma_code() could return LZMA_BUF_ERROR
when it shouldn't.
This has been here since the early days of liblzma.
It got triggered by the modifications made to the xz
tool in commit 18c10c30d2
but only when decompressing .lzma files. Somehow I managed
to miss testing that with Valgrind earlier.
This fixes <http://bugs.gentoo.org/show_bug.cgi?id=305591>.
Thanks to Rafał Mużyło for helping to debug it on IRC.
lzma_block.version has to be initialized even for
lzma_block_header_decode(). This way a future version
of liblzma won't allocate memory in a way that an old
application doesn't know how to free it.
The subtlety of this change is that all current apps
using lzma_block_header_decode() will keep working for
now, because the only possible version value is zero,
and lzma_block_header_decode() unconditionally sets the
version to zero even now. Unless fixed, these apps will
break in the future if a new version of the Block options
is ever needed.
If signal handlers haven't been established, then it's
useless to try to block them, especially since the sigset_t
used for blocking hasn't been initialized yet.
The opening of the destination file is now delayed a little.
The coder is initialized, and if decompressing, the memory
usage of the first Block compared against the memory
usage limit before the destination file is opened. This
means that if --force was used, the old "target" file won't
be deleted so easily when something goes wrong very early.
Thanks to Mark K for the bug report.
The above fix required some changes to progress message
handling. Now there is a separate function for setting and
printing the filename. It is used also in list.c.
list_file() now handles stdin correctly (gives an error).
A useless check for user_abort was removed from file_io.c.
This is a bit rough but should be useful for basic things.
Ideas (with detailed examples) about the output format are
welcome.
The output of --robot --list is not necessarily stable yet,
although I don't currently have any plans about changing it.
The man page hasn't been updated yet.
to stdout even if --force is used.
--force will still enable compression of symlinks, but only
in case they point to a regular file.
The new way simply seems more reasonable. It matches gzip's
behavior while the old one matched bzip2's behavior.
This breaks API and ABI but most apps are not affected
since most apps don't use this part of the API. You will
get a compile error if you are using anything that got
broken.
Summary of changes:
- Ability to store Stream Flags, which are needed
for random-access reading in multi-Stream files.
- Separate function to set size of Stream Padding.
- Iterator structure makes it possible to read the same
lzma_index from multiple threads at the same time.
- A lot faster code to locate Blocks.
- Removed lzma_index_equal() without adding anything
to replace it. I don't know what it should do exactly
with the new features and what actually needs this
function in the first place other than test_index.c,
which now has its own code to compare lzma_indexes.
lzma_index_read() didn't skip over Stream Padding
if it was the first record in the Index.
lzma_index_cat() didn't combine small Indexes correctly.
The test suite was updated to check for these bugs.
These bugs didn't affect the xz command line tool or
most users of liblzma in any way.
The Index decoder code didn't perfectly match the API docs,
which said that *i will be set to point to the decoded Index
only after decoding has succeeded. The docs were a bit unclear
too.
Now the decoder will initially set *i to NULL. *i will be set
to point to the decoded Index once decoding has succeeded.
This simplifies applications too, since it avoids dangling
pointers.
a regular file.
Sparse file creation can be disabled with --no-sparse.
I don't promise yet that the name of this option won't
change before 5.0.0. It's possible that the code, that
checks when it is safe to use sparse output on stdout,
is not good enough, and a more flexible command line
option is needed to configure sparse file handling.
Currently --robot works only with --info-memory and
--version. --help and --long-help work too, but --robot
has no effect on them.
Thanks to Jonathan Nieder for the original patches.
I had hoped to keep liblzma as purely a compression
library as possible (e.g. file I/O will go into
a different library), but it seems that applications
linking agaisnt liblzma need some way to determine
the memory usage limit, and knowing the amount of RAM
is one reasonable way to help making such decisions.
Thanks to Jonathan Nieder for the original patch.
Originally the idea was that using LZMA_FULL_FLUSH
with Stream encoder would read the filter chain
from the same array that was used to intialize the
Stream encoder. Since most apps wouldn't use
LZMA_FULL_FLUSH, most apps wouldn't need to keep
the filter chain available after initializing the
Stream encoder. However, due to my mistake, it
actually required keeping the array always available.
Since setting the new filter chain via the array
used at initialization time is not a nice way to do
it for a couple of reasons, this commit ditches it
and introduces lzma_filters_update(). This new function
replaces also the "persistent" flag used by LZMA2
(and to-be-designed Subblock filter), which was also
an ugly thing to do.
Thanks to Alexey Tourbin for reminding me about the problem
that Stream encoder used to require keeping the filter
chain allocated.
This will be needed internally by liblzma once I fix
a design mistake in the encoder API. This function may
be useful to applications too so it's good to export it.
A minus sign is larger, easier to see in a printout, and more
likely to use the same glyph as ASCII hyphen-minus in a terminal
than a hyphen. Since broken manual pagers do not find hyphens
when the user searches for a hyphen-minus, minus signs are also
easier to search for. So use minus signs instead of hyphens to
render sample terminal output.