Commit Graph

11 Commits

Author SHA1 Message Date
Lasse Collin 369f72fd65 Fix a buffer overflow in the LZMA encoder. It was due to my
misunderstanding of the code. There's no tiny fix for this
problem, so I also cleaned up the code in general.

This reduces the speed of the encoder 2-5 % in the fastest
compression mode ("lzma -1"). High compression modes should
have no noticeable performance difference.

This commit breaks things (especially LZMA_SYNC_FLUSH) but I
will fix them once the new format and LZMA2 has been roughly
implemented. Plain LZMA won't support LZMA_SYNC_FLUSH at all
and won't be supported in the new .lzma format. This may
change still but this is what it looks like now.

Support for known uncompressed size (that is, LZMA or LZMA2
without EOPM) is likely to go away. This means there will
be API changes.
2008-06-01 12:48:17 +03:00
Lasse Collin eb348a60b6 Switch to uint16_t as the type of range coder probabilities. 2008-04-24 19:22:53 +03:00
Lasse Collin 7ab493924e Use 64-bit integer as range encoder's cache size. This fixes a
theoretical data corruption, which should be very hard to trigger
even intentionally.
2008-04-24 17:30:51 +03:00
Lasse Collin 641998c3e1 Replaced the range decoder optimization that used arithmetic
right shift with as fast version that doesn't need
arithmetic right shift. Removed the related check from
configure.ac.
2008-03-24 16:38:40 +02:00
Lasse Collin ad999efd27 Take advantage of arithmetic right shift in range decoder. 2008-03-22 14:39:34 +02:00
Lasse Collin 54ec204f58 Omit invalid space from printf() format string
in price_table_gen.c.
2008-01-15 12:20:41 +02:00
Lasse Collin 9f9b198301 Convert bittree_get_price() and bittree_reverse_get_price()
from macros to inline functions.
2008-01-15 08:36:25 +02:00
Lasse Collin d13d693155 Added precomputed range coder probability price table. 2008-01-15 07:40:21 +02:00
Lasse Collin e22b37968d Major changes to LZ encoder, LZMA encoder, and range encoder.
These changes implement support for LZMA_SYNC_FLUSH in LZMA
encoder, and move the temporary buffer needed by range encoder
from lzma_range_encoder structure to lzma_lz_encoder.
2008-01-14 13:39:54 +02:00
Lasse Collin bbfd1f6ab0 Moved range decoder initialization (reading the first
five input bytes) from LZMA decoder to range decoder
header. Did the same for decoding of direct bits.
2008-01-04 20:45:05 +02:00
Lasse Collin 5d018dc035 Imported to git. 2007-12-09 00:42:33 +02:00