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.
Following up to 5e6cee07ab, some systems (eg
FreeBSD 12.0 64-bit) will crash if the stack-overflow margin is too small.
It seems the margin of 8192 bytes (or thereabouts) is always needed. This
commit adds this much margin if the requested stack size is too small.
Fixes issue #5824.
This adds a couple of commands to the run-tests script to print the diffs
of failed tests and also to clean up the .exp and .out files after failed
tests. (And a spelling error is fixed while we are touching nearby code.)
Travis is also updated to use these new commands, including using it for
more builds.
Since automatically formatting tests with black, we have lost one line of
code coverage. This adds an explicit test to ensure we are testing the
case that is no longer covered implicitly.
This adds the Python files in the tests/ directory to be formatted with
./tools/codeformat.py. The basics/ subdirectory is excluded for now so we
aren't changing too much at once.
In a few places `# fmt: off`/`# fmt: on` was used where the code had
special formatting for readability or where the test was actually testing
the specific formatting.
These were found by buiding the unix coverage variant on macOS (so clang
compiler). Mostly, these are fixing implicit cast of float/double to
mp_float_t which is one of those two and one mp_int_t to size_t fix for
good measure.
These are mainly used by the previous version of uasyncio which is now
replaced by a newer version, with built-in C module _uasyncio. Saves about
1300 bytes of flash.
https://www.python.org/dev/peps/pep-0475/
This implements something similar to PEP 475 on the unix port, and for the
VfsPosix class.
There are a few differences from the CPython implementation:
- Since we call mp_handle_pending() between any ENITR's, additional
functions could be called if MICROPY_ENABLE_SCHEDULER is enabled, not
just signal handlers.
- CPython only handles signal on the main thread, so other threads will
raise InterruptedError instead of retrying. On MicroPython,
mp_handle_pending() will currently raise exceptions on any thread.
A new macro MP_HAL_RETRY_SYSCALL is introduced to reduce duplicated code
and ensure that all instances behave the same. This will also allow other
ports that use POSIX-like system calls (and use, eg, VfsPosix) to provide
their own implementation if needed.
The stack size adjustment for detecting stack overflow in threads was not
taking into account that the requested stack size could be <= 8k, in which
case the subtraction would overflow. This is fixed in this commit by
ensuring that the adjustment can't be more than the available size.
This fixes the test tests/thread/thread_stacksize1.py which sometimes
crashes with a segmentation fault because of an uncaught NLR jump, which is
a "maximum recursion depth exceeded" exception.
Suggested-by: @dpgeorge
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.
Includes a test where the (non uasyncio) client does a RST on the
connection, as a simple TCP server/client test where both sides are using
uasyncio, and a test for TCP stream close then write.
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.
To enable lazy loading of submodules (among other things), which is very
useful for MicroPython libraries that want to have optional subcomponents.
Disabled explicitly on minimal ports.
This function is not used by the core but having it as part of the build
allows it to be used by user C modules, or board extensions. The linker
won't include it in the final firmware if it remains unused.
On CPython, and with pylint, the variables MATCH_ROM and SEARCH_ROM are
undefined. This code works in MicroPython because these variables are
constants and the MicroPython parser/compiler optimises them out. But it
is not valid Python because they are technically undefined within the scope
they are used.
This commit makes the code valid Python code. The const part is removed
completely because these constants are part of the public API and so cannot
be moved to the global scope (where they could still use the MicroPython
const optimisation).
