Increase maximum window size

* Maximum window size in 32-bit mode is 1GB, since allocations for 2GB fail
  on my Mac.
* Maximum window size in 64-bit mode is 2GB, since that is the largest
  power of 2 that works with the overflow prevention.
* Allow `--long=windowLog` to set the window log, along with
  `--zstd=wlog=#`. These options also set the window size during
  decompression, but don't override `--memory=#` if it is set.
* Present a helpful error message when the window size is too large during
  decompression.
* The long range matcher defaults to a hash log 7 less than the window log,
  which keeps it at 20 for window log 27.
* Keep the default long range matcher window size and the default maximum
  window size at 27 for the API and CLI.
* Add tests that use the maximum window size and hash size for compression
  and decompression.

This commit is contained in:

Nick Terrell

2017-09-26 14:00:01 -07:00

parent 8a4d0abc1c

commit c233bdbaee

12 changed files with 139 additions and 40 deletions

									
										lib/compress/zstd_ldm.h
									
		+1
		-1
	
												View File
												
				@@ -20,7 +20,7 @@ extern "C" {

				*  Long distance matching

				***************************************/

				#define ZSTD_LDM_WINDOW_LOG 27

				#define ZSTD_LDM_DEFAULT_WINDOW_LOG ZSTD_WINDOWLOG_DEFAULTMAX

				#define ZSTD_LDM_HASHEVERYLOG_NOTSET 9999

				/** ZSTD_compressBlock_ldm_generic() :