This module implements three main sets of C implementations that are used within SABnzbd:
- yEnc decoding and encoding using SIMD routines
- CRC32 calculations
- Non-blocking SSL-socket reading
- Marking files as sparse
Of course, they can also be used in any other application.
yEnc decoding and encoding performed by using yencode from animetosho,
which utilizes x86/ARM SIMD optimised routines if such CPU features are available.
We used the crcutil library for very fast CRC calculations.
When Python reads data from a non-blocking SSL socket, it is limited to receiving 16K data at once. This module implements a patched version that can read as much data is available at once. For more details, see the cpython pull request.
Uses Windows specific system calls to mark files as sparse and set the desired size.
On other platforms the same is achieved by calling truncate.
Use sabctools.bytearray_malloc(size) to get an bytearray that is uninitialized (not set to 0's).
This is much faster than the built-in bytearray(size) because the data inside the new bytearray will be whatever is present in the memory block.
As simple as running:
pip install sabctools --upgrade
When you want to compile from sources, you can run in the sabctools directory:
pip install .
To see which SIMD set was detected on your system, run:
python -c "import sabctools; print(sabctools.simd);"
To see if we could link to OpenSSL library on your system, run:
python -c "import sabctools; print(sabctools.openssl_linked);"
For testing we use pytest (install via pip install -r tests/requirements.txt) and test can simply be executed by browsing to the sabctools directory and running:
pytest
Note that tests can fail if git modified the line endings of data files when checking out the repository!