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.
encoder and decoder, and put the shared things to
block_private.h. Improved the checks a little so that
they may detect too big Compressed Size at initialization
time if lzma_options_block.total_size or .total_limit is
known.
Allow encoding and decoding Blocks with combinations of
fields that are not allowed by the file format specification.
Doing this requires that the application passes such a
combination in lzma_options_lzma; liblzma doesn't do that,
but it's not impossible that someone could find them useful
in some custom file format.
- Added lzma_memlimit_max() and lzma_memlimit_reached()
API functions.
- Added simple estimation of malloc()'s memory usage
overhead.
- Fixed integer overflow detection in lzma_memlimit_alloc().
- Made some white space cleanups and added more comments.
The description of lzma_memlimit_max() in memlimit.h is bad
and should be improved.
lzma_metadata.header_metadata_size == LZMA_VLI_VALUE_UNKNOWN
is not allowed at all. To indicate missing Header Metadata
Block, header_metadata_size must be set to zero. This is
what Metadata decoder does after this patch too.
Note that other missing fields in lzma_metadata are still
indicated with LZMA_VLI_VALUE_UNKNOWN. This isn't as
illogical as it sounds at first, because missing Size of
Header Metadata Block means that Header Metadata Block is
not present in the Stream. With other Metadata fields,
a missing field means only that the value is unknown.
liblzma as easy as using zlib, because the easy API
don't require developers to know any fancy LZMA options.
Note that Multi-Block Stream encoding is currently broken.
The easy API should be OK, the bug(s) are elsewhere.
function is still shared between encoder and decoder, but the
actual coding is in separate files for encoder and decoder.
There are now separate functions for the actual delta
calculation depending on if Delta is the last filter in the
chain or not. If it is the last, the new code copies the
data from input to output buffer and does the delta
calculation at the same time. The old code first copied the
data, then did the delta in the target buffer, which required
reading through the data twice.
Support for LZMA_SYNC_FLUSH was added to the Delta encoder.
This doesn't change anything in the file format.
table-based version from LZMA SDK 4.57. This should be
fast on most systems.
A simpler and smaller alternative version is also provided.
On some CPUs this can be even a little faster than the
default table-based version (see comments in fastpos.h),
but on most systems the table-based code is faster.
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