This further improves the documentation from commit
f36ca7982f. The previous wording of
"supported options" was slightly misleading since the options that are
printed are the ones that are relevant for encoding/decoding. It is not
about which options can or must be specified.
Reword "options required" to "supported options". The previous may have
suggested that the options listed were all required anytime a filter is
used for encoding or decoding. The reword makes this more clear that
adjusting the options is optional.
The \mainpage command is used in the first block of comments in lzma.h.
This changes the previously nearly empty index.html to use the first
comment block in lzma.h for its contents.
lzma.h is no longer documented separately, but this is for the better
since lzma.h only defined a few macros that users do not need to use.
The individual API header files all have a disclaimer that they should
not be #included directly, so there should be no confusion on the fact
that lzma.h should be the only header used by applications.
Additionally, the note "See ../lzma.h for information about liblzma as
a whole." was removed since lzma.h is now the main page of the
generated HTML and does not have its own page anymore. So it would be
confusing in the HTML version and was only a "nice to have" when
browsing the source files.
All functions now explicitly specify parameter and return values.
The notes and code annotations were moved before the parameter and
return value descriptions for consistency.
Also, the description above lzma_filter_encoder_is_supported() about
not being able to list available filters was removed since
lzma_str_list_filters() will do this.
The flag description for LZMA_STR_NO_VALIDATION was previously confusing
about the treatment for filters than cannot be used with .xz format
(lzma1) without using LZMA_STR_ALL_FILTERS. Now, it is clear that
LZMA_STR_NO_VALIDATION is not a super set of LZMA_STR_ALL_FILTERS.
The previous documentation for lzma_str_to_filters() was technically
correct, but misleading. lzma_str_to_filters() returns NULL on success,
which is in practice always defined to 0. This is the same value as
LZMA_OK, but lzma_str_to_filters() does not return lzma_ret so we should
be more clear.
lzma_str_to_filters() uses static error messages which makes
them not very precise. It tells the position in the string
where an error occurred though which helps quite a bit if
applications take advantage of it. Dynamic error messages can
be added later with a new flag if it seems important enough.
lzma_stream_encoder() and lzma_stream_encoder_mt() always assumed
this. Before this patch, failing lzma_filters_copy() could result
in free(invalid_pointer) or invalid memory reads in stream_encoder.c
or stream_encoder_mt.c.
To trigger this, allocating memory for a filter options structure
has to fail. These are tiny allocations so in practice they very
rarely fail.
Certain badness in the filter chain array could also make
lzma_filters_copy() fail but both stream_encoder.c and
stream_encoder_mt.c validate the filter chain before
trying to copy it, so the crash cannot occur this way.
There is a tiny risk of causing breakage: If an application
assigns lzma_stream.allocator to a non-const pointer, such
code won't compile anymore. I don't know why anyone would do
such a thing though, so in practice this shouldn't cause trouble.
Thanks to Jan Kratochvil for the 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.
Added lzma_nothrow for every function. It adds
throw() when the header is used in C++ code.
Some lzma_attrs were added or removed.
Lots of comments were improved.
lzma_memlimit_encoder and lzma_memlimit_decoder to
lzma_raw_encoder_memlimit and lzma_raw_decoder_memlimit. :-(
Now it is fixed. Hopefully it doesn't cause too much trouble
to those who already thought API is stable.
- Updated to the latest, probably final file format version.
- Command line tool reworked to not use threads anymore.
Threading will probably go into liblzma anyway.
- Memory usage limit is now about 30 % for uncompression
and about 90 % for compression.
- Progress indicator with --verbose
- Simplified --help and full --long-help
- Upgraded to the last LGPLv2.1+ getopt_long from gnulib.
- Some bug fixes
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.
Lasse Collin
Jia Tan
Dimitri Papadopoulos Orfanos