aboutsummaryrefslogtreecommitdiff
path: root/NEWS
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--NEWS202
1 files changed, 202 insertions, 0 deletions
diff --git a/NEWS b/NEWS
index 5fe60b4b..feae8a46 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,208 @@
XZ Utils Release Notes
======================
+5.4.0 (2022-12-13)
+
+ This bumps the minor version of liblzma because new features were
+ added. The API and ABI are still backward compatible with liblzma
+ 5.2.x and 5.0.x.
+
+ Since 5.3.5beta:
+
+ * All fixes from 5.2.10.
+
+ * The ARM64 filter is now stable. The xz option is now --arm64.
+ Decompression requires XZ Utils 5.4.0. In the future the ARM64
+ filter will be supported by XZ for Java, XZ Embedded (including
+ the version in Linux), LZMA SDK, and 7-Zip.
+
+ * Translations:
+
+ - Updated Catalan, Croatian, German, Romanian, and Turkish
+ translations.
+
+ - Updated German man page translations.
+
+ - Added Romanian man page translations.
+
+ Summary of new features added in the 5.3.x development releases:
+
+ * liblzma:
+
+ - Added threaded .xz decompressor lzma_stream_decoder_mt().
+ It can use multiple threads with .xz files that have multiple
+ Blocks with size information in Block Headers. The threaded
+ encoder in xz has always created such files.
+
+ Single-threaded encoder cannot store the size information in
+ Block Headers even if one used LZMA_FULL_FLUSH to create
+ multiple Blocks, so this threaded decoder cannot use multiple
+ threads with such files.
+
+ If there are multiple Streams (concatenated .xz files), one
+ Stream will be decompressed completely before starting the
+ next Stream.
+
+ - A new decoder flag LZMA_FAIL_FAST was added. It makes the
+ threaded decompressor report errors soon instead of first
+ flushing all pending data before the error location.
+
+ - New Filter IDs:
+ * LZMA_FILTER_ARM64 is for ARM64 binaries.
+ * LZMA_FILTER_LZMA1EXT is for raw LZMA1 streams that don't
+ necessarily use the end marker.
+
+ - Added lzma_str_to_filters(), lzma_str_from_filters(), and
+ lzma_str_list_filters() to convert a preset or a filter chain
+ string to a lzma_filter[] and vice versa. These should make
+ it easier to write applications that allow users to specify
+ custom compression options.
+
+ - Added lzma_filters_free() which can be convenient for freeing
+ the filter options in a filter chain (an array of lzma_filter
+ structures).
+
+ - lzma_file_info_decoder() to makes it a little easier to get
+ the Index field from .xz files. This helps in getting the
+ uncompressed file size but an easy-to-use random access
+ API is still missing which has existed in XZ for Java for
+ a long time.
+
+ - Added lzma_microlzma_encoder() and lzma_microlzma_decoder().
+ It is used by erofs-utils and may be used by others too.
+
+ The MicroLZMA format is a raw LZMA stream (without end marker)
+ whose first byte (always 0x00) has been replaced with
+ bitwise-negation of the LZMA properties (lc/lp/pb). It was
+ created for use in EROFS but may be used in other contexts
+ as well where it is important to avoid wasting bytes for
+ stream headers or footers. The format is also supported by
+ XZ Embedded (the XZ Embedded version in Linux got MicroLZMA
+ support in Linux 5.16).
+
+ The MicroLZMA encoder API in liblzma can compress into a
+ fixed-sized output buffer so that as much data is compressed
+ as can be fit into the buffer while still creating a valid
+ MicroLZMA stream. This is needed for EROFS.
+
+ - Added lzma_lzip_decoder() to decompress the .lz (lzip) file
+ format version 0 and the original unextended version 1 files.
+ Also lzma_auto_decoder() supports .lz files.
+
+ - lzma_filters_update() can now be used with the multi-threaded
+ encoder (lzma_stream_encoder_mt()) to change the filter chain
+ after LZMA_FULL_BARRIER or LZMA_FULL_FLUSH.
+
+ - In lzma_options_lzma, allow nice_len = 2 and 3 with the match
+ finders that require at least 3 or 4. Now it is internally
+ rounded up if needed.
+
+ - CLMUL-based CRC64 on x86-64 and E2K with runtime processor
+ detection. On 32-bit x86 it currently isn't available unless
+ --disable-assembler is used which can make the non-CLMUL
+ CRC64 slower; this might be fixed in the future.
+
+ - Building with --disable-threads --enable-small
+ is now thread-safe if the compiler supports
+ __attribute__((__constructor__)).
+
+ * xz:
+
+ - Using -T0 (--threads=0) will now use multi-threaded encoder
+ even on a single-core system. This is to ensure that output
+ from the same xz binary is identical on both single-core and
+ multi-core systems.
+
+ - --threads=+1 or -T+1 is now a way to put xz into
+ multi-threaded mode while using only one worker thread.
+ The + is ignored if the number is not 1.
+
+ - A default soft memory usage limit is now used for compression
+ when -T0 is used and no explicit limit has been specified.
+ This soft limit is used to restrict the number of threads
+ but if the limit is exceeded with even one thread then xz
+ will continue with one thread using the multi-threaded
+ encoder and this limit is ignored. If the number of threads
+ is specified manually then no default limit will be used;
+ this affects only -T0.
+
+ This change helps on systems that have very many cores and
+ using all of them for xz makes no sense. Previously xz -T0
+ could run out of memory on such systems because it attempted
+ to reserve memory for too many threads.
+
+ This also helps with 32-bit builds which don't have a large
+ amount of address space that would be required for many
+ threads. The default soft limit for -T0 is at most 1400 MiB
+ on all 32-bit platforms.
+
+ - Previously a low value in --memlimit-compress wouldn't cause
+ xz to switch from multi-threaded mode to single-threaded mode
+ if the limit cannot otherwise be met; xz failed instead. Now
+ xz can switch to single-threaded mode and then, if needed,
+ scale down the LZMA2 dictionary size too just like it already
+ did when it was started in single-threaded mode.
+
+ - The option --no-adjust no longer prevents xz from scaling down
+ the number of threads as that doesn't affect the compressed
+ output (only performance). Now --no-adjust only prevents
+ adjustments that affect compressed output, that is, with
+ --no-adjust xz won't switch from multi-threaded mode to
+ single-threaded mode and won't scale down the LZMA2
+ dictionary size.
+
+ - Added a new option --memlimit-mt-decompress=LIMIT. This is
+ used to limit the number of decompressor threads (possibly
+ falling back to single-threaded mode) but it will never make
+ xz refuse to decompress a file. This has a system-specific
+ default value because without any limit xz could end up
+ allocating memory for the whole compressed input file, the
+ whole uncompressed output file, multiple thread-specific
+ decompressor instances and so on. Basically xz could
+ attempt to use an insane amount of memory even with fairly
+ common files. The system-specific default value is currently
+ the same as the one used for compression with -T0.
+
+ The new option works together with the existing option
+ --memlimit-decompress=LIMIT. The old option sets a hard limit
+ that must not be exceeded (xz will refuse to decompress)
+ while the new option only restricts the number of threads.
+ If the limit set with --memlimit-mt-decompress is greater
+ than the limit set with --memlimit-compress, then the latter
+ value is used also for --memlimit-mt-decompress.
+
+ - Added new information to the output of xz --info-memory and
+ new fields to the output of xz --robot --info-memory.
+
+ - In --lzma2=nice=NUMBER allow 2 and 3 with all match finders
+ now that liblzma handles it.
+
+ - Don't mention endianness for ARM and ARM-Thumb filters in
+ --long-help. The filters only work for little endian
+ instruction encoding but modern ARM processors using
+ big endian data access still use little endian
+ instruction encoding. So the help text was misleading.
+ In contrast, the PowerPC filter is only for big endian
+ 32/64-bit PowerPC code. Little endian PowerPC would need
+ a separate filter.
+
+ - Added decompression support for the .lz (lzip) file format
+ version 0 and the original unextended version 1. It is
+ autodetected by default. See also the option --format on
+ the xz man page.
+
+ - Sandboxing enabled by default:
+ * Capsicum (FreeBSD)
+ * pledge(2) (OpenBSD)
+
+ * Scripts now support the .lz format using xz.
+
+ * A few new tests were added.
+
+ * The liblzma-specific tests are now supported in CMake-based
+ builds too ("make test").
+
+
5.3.5beta (2022-12-01)
* All fixes from 5.2.9.