Log Message:
xz: updated to 5.4.0

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").