Commit Graph

13 Commits

Author SHA1 Message Date
Damien George 55c76eaac1 extmod/uasyncio: Truncate negative sleeps to 0.
Otherwise a task that continuously awaits on a large negative sleep can
monopolise the scheduler (because its wake time is always less than
everything else in the pairing heap).

Signed-off-by: Damien George <damien@micropython.org>
2020-08-22 12:17:06 +10:00
Damien George 441460d81f extmod/uasyncio: Add StreamReader.readexactly(n) method.
It raises on EOFError instead of an IncompleteReadError (which is what
CPython does).  But the latter is derived from EOFError so code compatible
with MicroPython and CPython can be written by catching EOFError (eg see
included test).

Fixes issue #6156.

Signed-off-by: Damien George <damien@micropython.org>
2020-07-25 23:10:05 +10:00
Damien George a4c96fb3b0 extmod/uasyncio: Add asyncio.wait_for_ms function.
Fixes issue #6107.
2020-06-10 22:29:44 +10:00
Damien George 5f0661b4fe extmod/uasyncio: Change cannot to can't in error message, and test exp.
Follow up to 8e048d2548 which missed these.
2020-04-14 21:51:25 +10:00
Damien George db137e70dc extmod/uasyncio: Add Loop.new_event_loop method.
This commit adds Loop.new_event_loop() which is used to reset the singleton
event loop.  This functionality is put here instead of in Loop.close() to
make it possible to write code that is compatible with CPython.
2020-04-13 22:16:52 +10:00
Kevin Köck 15f41c2dbf extmod/uasyncio: Add global exception handling methods.
This commit adds support for global exception handling in uasyncio
according to the CPython error handling:
https://docs.python.org/3/library/asyncio-eventloop.html#error-handling-api

This allows a program to receive exceptions from detached tasks and log
them to an appropriate location, instead of them being printed to the REPL.

The implementation preallocates a context dictionary so in case of an
exception there shouldn't be any RAM allocation.

The approach here is compatible with CPython except that in CPython the
exception handler is called once the task that threw an uncaught exception
is freed, whereas in MicroPython the exception handler is called
immediately when the exception is thrown.
2020-04-04 10:37:00 +11:00
Damien George f97b5395ed extmod/uasyncio: Add StreamReader/StreamWriter as aliases of Stream cls.
To be compatible with CPython.  Fixes issue #5847.
2020-04-02 00:51:00 +11:00
Kevin Köck aca19c25d2 extmod/uasyncio: Add error message to Lock.release's RuntimeError.
Otherwise it can be hard to understand what the error is if a blank
RuntimeError is raised.
2020-04-02 00:40:23 +11:00
Damien George b389bc0afa extmod/uasyncio: Implement Loop.stop() to stop the event loop. 2020-04-02 00:14:18 +11:00
Damien George 711dd392d3 extmod/uasyncio: Don't create a Loop instance in get_event_loop().
The event loop is (for now) just a singleton so make it so that Loop
instances are not needed.
2020-04-01 23:56:31 +11:00
Damien George 3b68f36175 extmod/uasyncio: Add manifest.py for freezing uasyncio Py files. 2020-03-26 01:25:45 +11:00
Damien George bc009fdd62 extmod/uasyncio: Add optional implementation of core uasyncio in C.
Implements Task and TaskQueue classes in C, using a pairing-heap data
structure.  Using this reduces RAM use of each Task, and improves overall
performance of the uasyncio scheduler.
2020-03-26 01:25:45 +11:00
Damien George 63b9944382 extmod/uasyncio: Add new implementation of uasyncio module.
This commit adds a completely new implementation of the uasyncio module.
The aim of this version (compared to the original one in micropython-lib)
is to be more compatible with CPython's asyncio module, so that one can
more easily write code that runs under both MicroPython and CPython (and
reuse CPython asyncio libraries, follow CPython asyncio tutorials, etc).
Async code is not easy to write and any knowledge users already have from
CPython asyncio should transfer to uasyncio without effort, and vice versa.

The implementation here attempts to provide good compatibility with
CPython's asyncio while still being "micro" enough to run where MicroPython
runs. This follows the general philosophy of MicroPython itself, to make it
feel like Python.

The main change is to use a Task object for each coroutine.  This allows
more flexibility to queue tasks in various places, eg the main run loop,
tasks waiting on events, locks or other tasks.  It no longer requires
pre-allocating a fixed queue size for the main run loop.

A pairing heap is used to queue Tasks.

It's currently implemented in pure Python, separated into components with
lazy importing for optional components.  In the future parts of this
implementation can be moved to C to improve speed and reduce memory usage.
But the aim is to maintain a pure-Python version as a reference version.
2020-03-26 01:25:45 +11:00