It's not good to mix old and new API
ZSTD_resetCStream() doesn't just set pledgedSrcSize :
it also sets the CCtx for a single thread compression.
Problem is, when 2+ threads are defined in cctx->requestedParams,
ZSTD_compress_generic() will want to start MT compression,
since initialization is supposed to have already happened (thanks to ZSTD_resetCStream())
except that the underlying ZSTDMT_CCtx* object is not created,
resulting in a segfault.
This is an invalid construction
(correct one is to use ZSTD_CCtx_setPledgedSrcSize()).
I haven't found a nice way to mitigate this impact if someone makes the same mistake.
At some point, removing the old API to keep only the new API within fileio.c will limit these risks.
srcSize is read and provided at each file, not at resource creation.
This used to be useful with older API, because it could not re-adapt parameters between sessions.
At some point, it will be better to remove the old code, and only keep the new_api.
It works fine by now.
* 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.
for easier invocation.
- no longer expose frequency timer :
it's either useless, or stored internally in a static variable (init is only necessary once).
- UTIL_getTime() provides result by function return.
The timer used was only accurate up to 0.01 seconds. This timer is accurate up to 1 ns.
It is a monotonic timer that measures the real time difference, not on CPU time.
