maikel / senders-io Goto Github PK

An async_allocator<T> provides functions of an allocate but returning senders instead of the values.

The defaulted async allocator could be one that blockingly calls std::allocator<T>. But we could implement an async memory pool where an allocate sender completes when a suitable memory chunk gets available.

This can be used in an async::accept algorithm

I tried using stdexec from nvhpc-23.09.rc4 and HEAD, but both produce the same build error:

vscode ➜ /workspaces/cxx-init/senders-io (main) $ cmake --build build/ --parallel
[  2%] Building CXX object CMakeFiles/sio.dir/source/sio/const_buffer_span.cpp.o
[  8%] Building CXX object CMakeFiles/sio.dir/source/sio/io_uring/file_handle.cpp.o
[  8%] Building CXX object CMakeFiles/sio.dir/source/sio/mutable_buffer_span.cpp.o
[ 11%] Building CXX object CMakeFiles/sio.dir/source/sio/memory_pool.cpp.o
In file included from /workspaces/cxx-init/senders-io/source/sio/memory_pool.cpp:1:
/workspaces/cxx-init/senders-io/source/sio/./memory_pool.hpp:197:17: error: no matching function for call to object of type 'const __connect::connect_t'
  197 |       auto op = stdexec::connect(self, rcvr{})

Is there a specific commit that needs to be used?

See https://github.com/maikel/stdexec/blob/sequence-senders/include/exec/sequence/merge_each.hpp for an example impl

async::accept returns a sequence of socket_handles.

The lifetime of the underlying socket is bounded by the operations lifetime of the sequence elements

Come up with an interface to use io_urings registered buffers

I've discussed the async_allocator with kirk and its probably better to not give out senders to raw memory allocation but instead to async_new and async_delete which does both, allocation/construction and deallocation/destroy.

See https://git.kernel.dk/cgit/fio/tree/t/io_uring.c

See also https://github.com/maikel/stdexec/blob/sequence-senders/include/exec/sequence/any_sequence_sender_of.hpp

I have compiled inside a docker container with G++11. After running the tests, all but a single fail is observed. The test output below:

root@a100cse:/localscratch/senders-io/build/tests# ./test_sio 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
test_sio is a Catch v2.13.6 host application.
Run with -? for options

-------------------------------------------------------------------------------
async::resolve - Resolve ipv4 localhost
-------------------------------------------------------------------------------
/localscratch/senders-io/tests/net/test_resolve.cpp:22
...............................................................................

/localscratch/senders-io/tests/net/test_resolve.cpp:22: FAILED:
due to unexpected exception with message:
  Servname not supported for ai_socktype

===============================================================================
test cases:  87 |  86 passed | 1 failed
assertions: 306 | 305 passed | 1 failed

Great work! I am trying to experiment with the file_handle API in this library. I added stdexec dependency using CPM but couldn't get the library to compile. What version of the compiler and stdexec do I need to build this library?

Also, what is the use of passing multiple buffers to the read API? From what I can see, the read happens from a single offset, and the buffers are filled one after another. It would be nice to have a batched read that takes a span of buffers and a span of offsets in one-to-one correspondence.

The implementation for endpoints and adresses is incomplete. The resolver needs refactoring

Implement a timeout algorithm that uses when_any as default implementation

The current socket implementation of io_uring assumes an ip::endpoint. We should implement local::endpoint and a local::stream_protocol similar to asio https://www.boost.org/doc/libs/1_82_0/doc/html/boost_asio/reference/local__stream_protocol.html

reduce is last(scan)