This is a quick and slightly dirty fix to make the code
conform to the latest file format specification. Without
this patch, it's possible to make corrupt files by
specifying start offset that is not a multiple of the
filter's alignment. Custom start offset is almost never
used, so this was only a minor bug.
The xz command line tool doesn't validate the start offset,
so one will get a bit unclear error message if trying to use
an invalid start offset.
Don't use libtool convenience libraries to avoid recently
discovered long-standing subtle but somewhat severe bugs
in libtool (at least 1.5.22 and 2.2.6 are affected). It
was found when porting XZ Utils to Windows
<http://lists.gnu.org/archive/html/libtool/2009-06/msg00070.html>
but the problem is significant also e.g. on GNU/Linux.
Unless --disable-shared is passed to configure, static
library built from a set of convenience libraries will
contain PIC objects. That is, while libtool builds non-PIC
objects too, only PIC objects will be used from the
convenience libraries. On 32-bit x86 (tested on mobile XP2400+),
using PIC instead of non-PIC makes the decompressor 10 % slower
with the default CFLAGS.
So while xz was linked against static liblzma by default,
it got the slower PIC objects unless --disable-shared was
used. I tend develop and benchmark with --disable-shared
due to faster build time, so I hadn't noticed the problem
in benchmarks earlier.
This commit also adds support for building Windows resources
into liblzma and executables.
broken. API has changed a lot and it will still change a
little more here and there. The command line tool doesn't
have all the required changes to reflect the API changes, so
it's easy to get "internal error" or trigger assertions.
specification. Simplify things by removing most of the
support for known uncompressed size in most places.
There are some miscellaneous changes here and there too.
The API of liblzma has got many changes and still some
more will be done soon. While most of the code has been
updated, some things are not fixed (the command line tool
will choke with invalid filter chain, if nothing else).
Subblock filter is somewhat broken for now. It will be
updated once the encoded format of the Subblock filter
has been decided.
of the so called simple filters. If there is demand, limited
support for LZMA_SYNC_FLUSH may be added in future.
After this commit, using LZMA_SYNC_FLUSH shouldn't cause
undefined behavior in any situation.
in ia64_coder_init(). It triggered assert() in
simple_coder.c, and could have caused a buffer overflow.
This error was probably a copypaste mistake, since most
of the simple filters use unfiltered_max = 4.
It's not strictly needed there, and just complicates the
code. LZ encoder never even had this feature.
The primary reason to have uncompressed size tracking in
filter encoders was validating that the application
doesn't give different amount of input that it had
promised. A side effect was to validate internal workings
of liblzma.
Uncompressed size tracking is still present in the Block
encoder. Maybe it should be added to LZMA_Alone and raw
encoders too. It's simpler to have one coder just to
validate the uncompressed size instead of having it
in every filter.
Lasse Collin