Lrzip 0.620

I finally found some time to give lrzip some much needed love again. Fortunately the last release, 0.616, proved very stable for the vast majority of workloads so there was never any great need to give it attention, though little things slowly cropped up, so I've accumulated all the bugfixes till now to release a new stable version, 0.620.

Freecode has long since died so here's the link to the (ghetto) home and download page:


http://lrzip.kolivas.org/

and the git source code page:

https://github.com/ckolivas/lrzip


Summary of changes:
- It would previously crash if trying to decompress from STDIN with a file that was too large to fit in ram which has now been fixed.
- It would previously fail to decompress files that were too large to fit in ram decompressed, now fixed.
- There were some scenarios lrzip would run out of ram when there was plenty to allocate, now fixed.
- Some other unix platforms would consider locking a mutex in one thread and releasing it in another a bug, so I've converted the use of those mutexes to anonymous semaphores.
- In order to maintain compatibility with platforms that don't properly support anonymous semaphores (OSX I'm looking at you), I've added the use of my custom fake semaphores as discussed here: unnamed-semaphores-and-pososx
- Some files would have their size reported wrongly with -i, now fixed.
- Added the ability to limit the use of ram with -m since lrzip happily uses all of it normally.
- Other minor changes and fixes for rare corner cases.


The changelog:
* Increase maxram when we abandon use of temporary input/output buffers
* Don't delete the tmpinfile when decompressing from stdin before allowing seek
to end to succeed in checking md5
* Use temporary file from read_seekto when STDIN will not fit in the ram input
buffer
* Remove unused read_i64 function
* Add message about issue tracker in BUGS
* Use a common exit path iin lrzip_compress/decompress and fix lr leak on
successful return
* Fix parenthesis placement inside of unlikely().
* Clear sa_mask and sa_handler before calling sigaction().
* Fix for lrzip -i. Decompressed size wrong
* added '-m' command line option
* Fix wrong README file being included in Makefile
* Pass strict sizes to decompress length, rounding up only the amount we're
allocating to not confuse decompression libraries
* Convert the thread locking to use cksems
* Add cksems to util.h
* Fix 'Failed to malloc ckbuf in hash_search2' with very large files.
* Round up compression and decompression buffers to page size since malloc will
allocate them that large anyway.
* Increase the compressed buffer size given to libzpaq in case of incompressible
data since it does not check if it's trying to write beyond the end of the
buffer.
* Provide a helper function to round a value up to the nearest page size for
malloc optimisations.