Commit Graph

780 Commits

Author SHA1 Message Date
Lasse Collin 386394fc9f liblzma: memcmplen: Use ctz32() from tuklib_integer.h.
The same compiler-specific #ifdefs are already in tuklib_integer.h
2019-06-01 21:36:13 +03:00
Lasse Collin 264ab971ce tuklib_integer: Cleanup MSVC-specific code. 2019-06-01 21:30:03 +03:00
Lasse Collin 33773c6f2a liblzma: Use unaligned_readXXne functions instead of type punning.
Now gcc -fsanitize=undefined should be clean.

Thanks to Jeffrey Walton.
2019-06-01 19:01:21 +03:00
Lasse Collin 3bc112c2d3 tuklib_integer: Improve unaligned memory access.
Now memcpy() or GNU C packed structs for unaligned access instead
of type punning. See the comment in this commit for details.

Avoiding type punning with unaligned access is needed to
silence gcc -fsanitize=undefined.

New functions: unaliged_readXXne and unaligned_writeXXne where
XX is 16, 32, or 64.
2019-06-01 18:41:16 +03:00
Lasse Collin 2a22de439e liblzma: Avoid memcpy(NULL, foo, 0) because it is undefined behavior.
I should have always known this but I didn't. Here is an example
as a reminder to myself:

    int mycopy(void *dest, void *src, size_t n)
    {
        memcpy(dest, src, n);
        return dest == NULL;
    }

In the example, a compiler may assume that dest != NULL because
passing NULL to memcpy() would be undefined behavior. Testing
with GCC 8.2.1, mycopy(NULL, NULL, 0) returns 1 with -O0 and -O1.
With -O2 the return value is 0 because the compiler infers that
dest cannot be NULL because it was already used with memcpy()
and thus the test for NULL gets optimized out.

In liblzma, if a null-pointer was passed to memcpy(), there were
no checks for NULL *after* the memcpy() call, so I cautiously
suspect that it shouldn't have caused bad behavior in practice,
but it's hard to be sure, and the problematic cases had to be
fixed anyway.

Thanks to Jeffrey Walton.
2019-05-13 20:05:17 +03:00
Lasse Collin 4adb8288ab xz: Update xz man page date. 2019-05-11 20:54:12 +03:00
Antoine Cœur 2fb0ddaa55 spelling 2019-05-11 20:52:37 +03:00
Lasse Collin 4ed3396061 xz: In xz -lvv look at the widths of the check names too.
Now the widths of the check names is used to adjust the width
of the Check column. This way there no longer is a need to restrict
the widths of the check names to be at most ten terminal-columns.
2019-05-01 18:43:10 +03:00
Lasse Collin 2f4281a100 xz: Fix xz -lvv column alignment to look at the translated strings. 2019-05-01 18:33:25 +03:00
Lasse Collin a750c35a7d xz: Automatically align column headings in xz -lvv. 2019-03-04 21:20:39 +02:00
Lasse Collin 6cb42e8aa1 xz: Automatically align strings ending in a colon in --list output.
This should avoid alignment errors in translations with these
strings.
2019-03-04 21:16:59 +02:00
Lasse Collin b55d79461d xz: Fix a crash in progress indicator when in passthru mode.
"xz -dcfv not_an_xz_file" crashed (all four options are
required to trigger it). It caused xz to call
lzma_get_progress(&strm, ...) when no coder was initialized
in strm. In this situation strm.internal is NULL which leads
to a crash in lzma_get_progress().

The bug was introduced when xz started using lzma_get_progress()
to get progress info for multi-threaded compression, so the
bug is present in versions 5.1.3alpha and higher.

Thanks to Filip Palian <Filip.Palian@pjwstk.edu.pl> for
the bug report.
2018-12-20 20:39:20 +02:00
Lasse Collin 4ae5526de0 xz: Update man page timestamp. 2018-11-22 17:20:31 +02:00
Pavel Raiskup 6a36d0d5f4 'have have' typos 2018-11-22 17:19:09 +02:00
Lasse Collin a18ae42a79 liblzma: Don't verify header CRC32s if building for fuzz testing.
FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION is #defined when liblzma
is being built for fuzz testing.

Most fuzzed inputs would normally get rejected because of incorrect
CRC32 and the actual header decoding code wouldn't get fuzzed.
Disabling CRC32 checks avoids this problem. The fuzzer program
must still use LZMA_IGNORE_CHECK flag to disable verification of
integrity checks of uncompressed data.
2018-10-26 22:49:10 +03:00
Lasse Collin f76f7516d6 xzless: Rename unused variables to silence static analysers.
In this particular case I don't see this affecting readability
of the code.

Thanks to Pavel Raiskup.
2018-07-27 18:10:44 +03:00
Lasse Collin 3cbcaeb07e liblzma: Remove an always-true condition from lzma_index_cat().
This should help static analysis tools to see that newg
isn't leaked.

Thanks to Pavel Raiskup.
2018-07-27 16:02:58 +03:00
Lasse Collin 76762ae609 liblzma: Improve lzma_properties_decode() API documentation. 2018-05-19 21:23:25 +03:00
Lasse Collin 2267f5b0d2 Bump the version number to 5.3.1alpha. 2018-04-29 18:58:19 +03:00
Ben Boeckel bc19799169 nothrow: use noexcept for C++11 and newer
In C++11, the `throw()` specifier is deprecated and `noexcept` is
preffered instead.
2018-02-06 18:41:45 +02:00
Lasse Collin fb6d4f83cb liblzma: Remove incorrect #ifdef from range_common.h.
In most cases it was harmless but it could affect some
custom build systems.

Thanks to Pippijn van Steenhoven.
2018-02-06 18:02:48 +02:00
Lasse Collin 713bbc1a80 tuklib_integer: New Intel C compiler needs immintrin.h.
Thanks to Melanie Blower (Intel) for the patch.
2018-01-10 21:54:27 +02:00
Lasse Collin 94e3f986aa Fix or hide warnings from GCC 7's -Wimplicit-fallthrough. 2017-08-14 20:08:33 +03:00
Lasse Collin a015cd1f90 xz: Fix "xz --list --robot missing_or_bad_file.xz".
It ended up printing an uninitialized char-array when trying to
print the check names (column 7) on the "totals" line.

This also changes the column 12 (minimum xz version) to
50000002 (xz 5.0.0) instead of 0 when there are no valid
input files.

Thanks to kidmin for the bug report.
2017-05-23 18:34:43 +03:00
Lasse Collin 8269782283 xz: Use lzma_file_info_decoder() for --list. 2017-04-24 19:48:23 +03:00
Lasse Collin e353d0b1cc liblzma: Add lzma_file_info_decoder(). 2017-04-24 19:48:04 +03:00
Lasse Collin 8c9842c265 liblzma: Rename LZMA_SEEK to LZMA_SEEK_NEEDED and seek_in to seek_pos. 2017-04-21 15:05:16 +03:00
Lasse Collin 662b27c417 Update the home page URLs to HTTPS. 2017-04-19 22:17:35 +03:00
Lasse Collin c28f0b3d00 xz: Add io_seek_src(). 2017-04-05 18:47:22 +03:00
Lasse Collin bba477257d xz: Use POSIX_FADV_RANDOM for in "xz --list" mode.
xz --list is random access so POSIX_FADV_SEQUENTIAL was clearly
wrong.
2017-03-30 22:01:54 +03:00
Lasse Collin 310d19816d liblzma: Make lzma_index_decoder_init() visible to other liblzma funcs.
This is to allow other functions to use it without going
via the public API (lzma_index_decoder()).
2017-03-30 20:03:05 +03:00
Lasse Collin a27920002d liblzma: Add generic support for input seeking (LZMA_SEEK).
Also mention LZMA_SEEK in xz/message.c to silence a warning.
2017-03-30 20:00:09 +03:00
Lasse Collin a0b1dda409 liblzma: Fix lzma_memlimit_set(strm, 0).
The 0 got treated specially in a buggy way and as a result
the function did nothing. The API doc said that 0 was supposed
to return LZMA_PROG_ERROR but it didn't.

Now 0 is treated as if 1 had been specified. This is done because
0 is already used to indicate an error from lzma_memlimit_get()
and lzma_memusage().

In addition, lzma_memlimit_set() no longer checks that the new
limit is at least LZMA_MEMUSAGE_BASE. It's counter-productive
for the Index decoder and was actually needed only by the
auto decoder. Auto decoder has now been modified to check for
LZMA_MEMUSAGE_BASE.
2017-03-30 19:51:14 +03:00
Lasse Collin 84462afaad liblzma: Similar memlimit fix for stream_, alone_, and auto_decoder. 2017-03-30 19:16:55 +03:00
Lasse Collin cbc7401793 liblzma: Fix handling of memlimit == 0 in lzma_index_decoder().
It returned LZMA_PROG_ERROR, which was done to avoid zero as
the limit (because it's a special value elsewhere), but using
LZMA_PROG_ERROR is simply inconvenient and can cause bugs.

The fix/workaround is to treat 0 as if it were 1 byte. It's
effectively the same thing. The only weird consequence is
that then lzma_memlimit_get() will return 1 even when 0 was
specified as the limit.

This fixes a very rare corner case in xz --list where a specific
memory usage limit and a multi-stream file could print the
error message "Internal error (bug)" instead of saying that
the memory usage limit is too low.
2017-03-30 19:10:55 +03:00
Lasse Collin d4a0462abe liblzma: Avoid multiple definitions of lzma_coder structures.
Only one definition was visible in a translation unit.
It avoided a few casts and temp variables but seems that
this hack doesn't work with link-time optimizations in compilers
as it's not C99/C11 compliant.

Fixes:
http://www.mail-archive.com/xz-devel@tukaani.org/msg00279.html
2016-11-21 20:24:50 +02:00
Lasse Collin df8f446e3a tuklib_cpucores: Add support for sched_getaffinity().
It's available in glibc (GNU/Linux, GNU/kFreeBSD). It's better
than sysconf(_SC_NPROCESSORS_ONLN) because sched_getaffinity()
gives the number of cores available to the process instead of
the total number of cores online.

As a side effect, this commit fixes a bug on GNU/kFreeBSD where
configure would detect the FreeBSD-specific cpuset_getaffinity()
but it wouldn't actually work because on GNU/kFreeBSD it requires
using -lfreebsd-glue when linking. Now the glibc-specific function
will be used instead.

Thanks to Sebastian Andrzej Siewior for the original patch
and testing.
2016-10-24 18:51:36 +03:00
Lasse Collin 446e4318fa xz: Fix copying of timestamps on Windows.
xz used to call utime() on Windows, but its result gets lost
on close(). Using _futime() seems to work.

Thanks to Martok for reporting the bug:
http://www.mail-archive.com/xz-devel@tukaani.org/msg00261.html
2016-06-30 20:27:36 +03:00
Lasse Collin 1b0ac0c53c xz: Silence warnings from -Wlogical-op.
Thanks to Evan Nemerson.
2016-06-16 22:46:02 +03:00
Lasse Collin c83b7a0334 Build: Fix = to += for xz_SOURCES in src/xz/Makefile.am.
Thanks to Christian Kujau.
2016-04-10 20:55:49 +03:00
Lasse Collin ac398c3baf liblzma: Disable external SHA-256 by default.
This is the sane thing to do. The conflict with OpenSSL
on some OSes and especially that the OS-provided versions
can be significantly slower makes it clear that it was
a mistake to have the external SHA-256 support enabled by
default.

Those who want it can now pass --enable-external-sha256 to
configure. INSTALL was updated with notes about OSes where
this can be a bad idea.

The SHA-256 detection code in configure.ac had some bugs that
could lead to a build failure in some situations. These were
fixed, although it doesn't matter that much now that the
external SHA-256 is disabled by default.

MINIX >= 3.2.0 uses NetBSD's libc and thus has SHA256_Init
in libc instead of libutil. Support for the libutil version
was removed.
2016-03-13 20:21:49 +02:00
Lasse Collin faf302137e tuklib_physmem: Hopefully silence a warning on Windows. 2015-11-08 20:16:10 +02:00
Lasse Collin 14115f84a3 liblzma: Make Valgrind happier with optimized (gcc -O2) liblzma.
When optimizing, GCC can reorder code so that an uninitialized
value gets used in a comparison, which makes Valgrind unhappy.
It doesn't happen when compiled with -O0, which I tend to use
when running Valgrind.

Thanks to Rich Prohaska. I remember this being mentioned long
ago by someone else but nothing was done back then.
2015-11-04 23:14:00 +02:00
Lasse Collin f4c95ba94b liblzma: Rename lzma_presets.c back to lzma_encoder_presets.c.
It would be too annoying to update other build systems
just because of this.
2015-11-03 20:55:45 +02:00
Lasse Collin cb3111e3ed xz: Make xz buildable even when encoders or decoders are disabled.
The patch is quite long but it's mostly about adding new #ifdefs
to omit code when encoders or decoders have been disabled.

This adds two new #defines to config.h: HAVE_ENCODERS and
HAVE_DECODERS.
2015-11-03 20:29:33 +02:00
Lasse Collin 4cc584985c Build: Build LZMA1/2 presets also when only decoder is wanted.
People shouldn't rely on the presets when decoding raw streams,
but xz uses the presets as the starting point for raw decoder
options anyway.

lzma_encocder_presets.c was renamed to lzma_presets.c to
make it clear it's not used solely by the encoder code.
2015-11-03 18:06:40 +02:00
Lasse Collin b0bc3e0385 Build: Don't omit lzma_cputhreads() unless using --disable-threads.
Previously it was omitted if encoders were disabled
with --disable-encoders. It didn't make sense and
it also broke the build.
2015-11-03 17:41:54 +02:00
Lasse Collin c6bf438ab3 liblzma: Fix a build failure related to external SHA-256 support.
If an appropriate header and structure were found by configure,
but a library with a usable SHA-256 functions wasn't, the build
failed.
2015-11-02 18:16:51 +02:00
Lasse Collin e18adc56f2 xz: Always close the file before trying to delete it.
unlink() can return EBUSY in errno for open files on some
operating systems and file systems.
2015-11-02 15:19:10 +02:00
Lasse Collin 21515d79d7 liblzma: Fix lzma_index_dup() for empty Streams.
Stream Flags and Stream Padding weren't copied from
empty Streams.
2015-10-12 20:45:15 +03:00
Lasse Collin 09f395b6b3 liblzma: Add a note to index.c for those using static analyzers. 2015-10-12 20:31:44 +03:00
Lasse Collin 3bf857edfe liblzma: Fix a memory leak in error path of lzma_index_dup().
lzma_index_dup() calls index_dup_stream() which, in case of
an error, calls index_stream_end() to free memory allocated
by index_stream_init(). However, it illogically didn't
actually free the memory. To make it logical, the tree
handling code was modified a bit in addition to changing
index_stream_end().

Thanks to Evan Nemerson for the bug report.
2015-10-12 20:29:09 +03:00
Lasse Collin fbbb295a91 liblzma: A MSVC-specific hack isn't needed with MSVC 2013 and newer. 2015-07-12 20:48:19 +03:00
Lasse Collin 49c26920d6 xz: Document that threaded decompression hasn't been implemented yet. 2015-05-11 21:26:16 +03:00
Lasse Collin 6bd0349c58 Revert "xz: Use pipe2() if available."
This reverts commit 7a11c4a8e5.
It is a problem when libc has pipe2() but the kernel is too
old to have pipe2() and thus pipe2() fails. In xz it's pointless
to have a fallback for non-functioning pipe2(); it's better to
avoid pipe2() completely.

Thanks to Michael Fox for the bug report.
2015-04-20 20:17:48 +03:00
Lasse Collin fc0df0f8db xz: Fix the Capsicum rights on user_abort_pipe. 2015-04-01 14:45:25 +03:00
Lasse Collin 1238381143 xz: Add support for sandboxing with Capsicum.
The sandboxing is used conditionally as described in main.c.
This isn't optimal but it was much easier to implement than
a full sandboxing solution and it still covers the most common
use cases where xz is writing to standard output. This should
have practically no effect on performance even with small files
as fork() isn't needed.

C and locale libraries can open files as needed. This has been
fine in the past, but it's a problem with things like Capsicum.
io_sandbox_enter() tries to ensure that various locale-related
files have been loaded before cap_enter() is called, but it's
possible that there are other similar problems which haven't
been seen yet.

Currently Capsicum is available on FreeBSD 10 and later
and there is a port to Linux too.

Thanks to Loganaden Velvindron for help.
2015-03-31 22:19:34 +03:00
Lasse Collin 3717885f9e Bump version to 5.3.0alpha and soname to 5.3.99.
The idea of 99 is that it looks a bit weird in this context.
For new features there's no API/ABI stability in devel versions.
2015-03-30 22:44:02 +03:00
Lasse Collin 25263fd9e7 Fix the detection of installed RAM on QNX.
The earlier version compiled but didn't actually work
since sysconf(_SC_PHYS_PAGES) always fails (or so I was told).

Thanks to Ole André Vadla Ravnås for the patch and testing.
2015-03-29 22:13:48 +03:00
Lasse Collin e0ea6737b0 xz: size_t/uint32_t cleanup in options.c. 2015-03-07 22:05:57 +02:00
Lasse Collin 8bcca29a65 xz: Fix a comment and silence a warning in message.c. 2015-03-07 22:04:23 +02:00
Lasse Collin f243f5f44c liblzma: Silence more uint32_t vs. size_t warnings. 2015-03-07 22:01:00 +02:00
Lasse Collin 7f0a4c50f4 xz: Make arg_count an unsigned int to silence a warning.
Actually the value of arg_count cannot exceed INT_MAX
but it's nicer as an unsigned int.
2015-03-07 19:54:00 +02:00
Lasse Collin f6ec468015 liblzma: Fix a warning in index.c. 2015-03-07 19:33:17 +02:00
Lasse Collin dec11497a7 Bump version and soname for 5.2.1. 2015-02-26 16:53:44 +02:00
Lasse Collin 7a11c4a8e5 xz: Use pipe2() if available. 2015-02-22 19:38:48 +02:00
Lasse Collin 117d962685 liblzma: Fix a compression-ratio regression in LZMA1/2 in fast mode.
The bug was added in the commit
f48fce093b and thus
affected 5.1.4beta and 5.2.0. Luckily the bug cannot
cause data corruption or other nasty things.
2015-02-21 23:40:26 +02:00
Lasse Collin ae984e31c1 xz: Fix the fcntl() usage when creating a pipe for the self-pipe trick.
Now it reads the old flags instead of blindly setting O_NONBLOCK.
The old code may have worked correctly, but this is better.
2015-02-21 23:00:19 +02:00
Lasse Collin d935b0cdf3 tuklib_cpucores: Use cpuset_getaffinity() on FreeBSD if available.
In FreeBSD, cpuset_getaffinity() is the preferred way to get
the number of available cores.

Thanks to Rui Paulo for the patch. I edited it slightly, but
hopefully I didn't break anything.
2015-02-10 15:28:30 +02:00
Lasse Collin eb61bc58c2 xzdiff: Make the mktemp usage compatible with FreeBSD's mktemp.
Thanks to Rui Paulo for the fix.
2015-02-09 22:08:37 +02:00
Lasse Collin b9a5b6b7a2 Add a few casts to tuklib_integer.h to silence possible warnings.
I heard that Visual Studio 2013 gave warnings without the casts.

Thanks to Gabi Davar.
2015-02-03 21:45:53 +02:00
Lasse Collin c45757135f liblzma: Set LZMA_MEMCMPLEN_EXTRA depending on the compare method. 2015-01-26 21:24:39 +02:00
Lasse Collin fec88d41e6 liblzma: Silence harmless Valgrind errors.
Thanks to Torsten Rupp for reporting this. I had
forgotten to run Valgrind before the 5.2.0 release.
2015-01-26 20:39:28 +02:00
Lasse Collin a9b45badfe xz: Fix comments. 2015-01-09 21:50:19 +02:00
Lasse Collin 4170edc914 xz: Don't fail if stdout doesn't support O_NONBLOCK.
This is similar to the case with stdin.

Thanks to Brad Smith for the bug report and testing
on OpenBSD.
2015-01-09 21:34:06 +02:00
Lasse Collin 04bbc0c284 xz: Fix a memory leak in DOS-specific code. 2015-01-07 19:18:20 +02:00
Lasse Collin f0f1f6c723 xz: Don't fail if stdin doesn't support O_NONBLOCK.
It's a problem at least on OpenBSD which doesn't support
O_NONBLOCK on e.g. /dev/null. I'm not surprised if it's
a problem on other OSes too since this behavior is allowed
in POSIX-1.2008.

The code relying on this behavior was committed in June 2013
and included in 5.1.3alpha released on 2013-10-26. Clearly
the development releases only get limited testing.
2015-01-07 19:08:06 +02:00
Lasse Collin 6060f7dc76 Bump version and soname for 5.2.0.
I know that soname != app version, but I skip AGE=1
in -version-info to make the soname match the liblzma
version anyway. It doesn't hurt anything as long as
it doesn't conflict with library versioning rules.
2014-12-21 18:11:17 +02:00
Lasse Collin 2cb82ff21c Fix build when --disable-threads is used. 2014-12-21 18:00:38 +02:00
Lasse Collin 42e97a3264 xz: Fix a comment. 2014-12-21 14:07:54 +02:00
Lasse Collin 7f7d093de7 xz: Update the man page about --threads. 2014-12-16 21:00:09 +02:00
Lasse Collin 009823448b xz: Update the man page about --block-size. 2014-12-16 20:57:43 +02:00
Lasse Collin 1190c641af liblzma: Document how lzma_mt.block_size affects memory usage. 2014-12-02 20:04:07 +02:00
Lasse Collin 34f9e40a0a Remove LZMA_UNSTABLE macro. 2014-11-26 20:12:27 +02:00
Lasse Collin 6d9c0ce9f2 liblzma: Update lzma_stream_encoder_mt() API docs. 2014-11-26 20:10:33 +02:00
Lasse Collin 2301f3f05d liblzma: Verify the filter chain in threaded encoder initialization.
This way an invalid filter chain is detected at the Stream
encoder initialization instead of delaying it to the first
call to lzma_code() which triggers the initialization of
the actual filter encoder(s).
2014-11-25 12:32:05 +02:00
Lasse Collin 7b03a15cea xzdiff: Use mkdir if mktemp isn't available. 2014-11-10 18:54:40 +02:00
Lasse Collin f8c13e5e36 xzdiff: Create a temporary directory to hold a temporary file.
This avoids the possibility of "File name too long" when
creating a temp file when the input file name is very long.

This also means that other users on the system can no longer
see the input file names in /tmp (or whatever $TMPDIR is)
since the temporary directory will have a generic name. This
usually doesn't matter since on many systems one can see
the arguments given to all processes anyway.

The number X chars to mktemp where increased from 6 to 10.

Note that with some shells temp files or dirs won't be used at all.
2014-11-10 18:45:01 +02:00
Lasse Collin 7716dcf9df liblzma: Fix lzma_mt.preset in lzma_stream_encoder_mt_memusage().
It read the filter chain from a wrong variable. This is a similar
bug that was fixed in 9494fb6d0f.
2014-11-10 15:38:47 +02:00
Lasse Collin c923b140b2 Build: Prepare to support Automake's subdir-objects.
Due to a bug in Automake, subdir-objects won't be enabled
for now.

http://debbugs.gnu.org/cgi/bugreport.cgi?bug=17354

Thanks to Daniel Richard G. for the original patches.
2014-10-29 21:15:35 +02:00
Lasse Collin 076258cc45 Add support for AmigaOS/AROS to tuklib_physmem().
Thanks to Fredrik Wikstrom.
2014-10-09 19:41:51 +03:00
Lasse Collin efa7b0a210 xzgrep: Avoid passing both -q and -l to grep.
The behavior of grep -ql varies:
  - GNU grep behaves like grep -q.
  - OpenBSD grep behaves like grep -l.

POSIX doesn't make it 100 % clear what behavior is expected.
Anyway, using both -q and -l at the same time makes no sense
so both options simply should never be used at the same time.

Thanks to Christian Weisgerber.
2014-10-09 18:42:14 +03:00
Lasse Collin d62028b4c1 liblzma: Fix a portability problem in Makefile.am.
POSIX supports $< only in inference rules (suffix rules).
Using it elsewhere is a GNU make extension and doesn't
work e.g. with OpenBSD make.

Thanks to Christian Weisgerber for the patch.
2014-09-20 19:42:56 +03:00
Lasse Collin c35de31d42 Bump the version number to 5.1.4beta. 2014-09-14 21:54:09 +03:00
Lasse Collin 6b5e3b9eff xz: Add --ignore-check. 2014-08-05 22:32:36 +03:00
Lasse Collin 9adbc2ff37 liblzma: Add support for LZMA_IGNORE_CHECK. 2014-08-05 22:15:07 +03:00
Lasse Collin 0e0f34b8e4 liblzma: Add support for lzma_block.ignore_check.
Note that this slightly changes how lzma_block_header_decode()
has been documented. Earlier it said that the .version is set
to the lowest required value, but now it says that the .version
field is kept unchanged if possible. In practice this doesn't
affect any old code, because before this commit the only
possible .version was 0.
2014-08-05 22:03:30 +03:00
Lasse Collin 71e1437ab5 liblzma: Use lzma_memcmplen() in the BT3 match finder.
I had missed this when writing the commit
5db75054e9.

Thanks to Jun I Jin.
2014-08-04 19:25:58 +03:00
Lasse Collin 5dcffdbcc2 liblzma: SHA-256: Optimize the Maj macro slightly.
The Maj macro is used where multiple things are added
together, so making Maj a sum of two expressions allows
some extra freedom for the compiler to schedule the
instructions.

I learned this trick from
<http://www.hackersdelight.org/corres.txt>.
2014-08-03 21:32:25 +03:00
Lasse Collin a9477d1e0c liblzma: SHA-256: Optimize the way rotations are done.
This looks weird because the rotations become sequential,
but it helps quite a bit on both 32-bit and 64-bit x86:

  - It requires fewer instructions on two-operand
    instruction sets like x86.

  - It requires one register less which matters especially
    on 32-bit x86.

I hope this doesn't hurt other archs.

I didn't invent this idea myself, but I don't remember where
I saw it first.
2014-08-03 21:08:12 +03:00