Commit Graph

4 Commits

Author SHA1 Message Date
stijn 40ad8f1666 all: Rename "sys" module to "usys".
This is consistent with the other 'micro' modules and allows implementing
additional features in Python via e.g. micropython-lib's sys.

Note this is a breaking change (not backwards compatible) for ports which
do not enable weak links, as "import sys" must now be replaced with
"import usys".
2020-09-04 00:10:24 +10:00
David Lechner 3dc324d3f1 tests: Format all Python code with black, except tests in basics subdir.
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.
2020-03-30 13:21:58 +11:00
Damien George 96fd80db13 py/objexcept: Prevent infinite recursion when allocating exceptions.
The aim of this patch is to rewrite the functions that create exception
instances (mp_obj_exception_make_new and mp_obj_new_exception_msg_varg) so
that they do not call any functions that may raise an exception.  Otherwise
it's possible to create infinite recursion with an exception being raised
while trying to create an exception object.

The two main things that are done to accomplish this are:
1. Change mp_obj_new_exception_msg_varg to just format the string, then
   call mp_obj_exception_make_new to actually create the exception object.
2. In mp_obj_exception_make_new and mp_obj_new_exception_msg_varg try to
   allocate all memory first using functions that don't raise exceptions
   If any of the memory allocations fail (return NULL) then degrade
   gracefully by trying other options for memory allocation, eg using the
   emergency exception buffer.
3. Use a custom printer backend to conservatively format strings: if it
   can't allocate memory then it just truncates the string.

As part of this rewrite, raising an exception without a message, like
KeyError(123), will now use the emergency buffer to store the arg and
traceback data if there is no heap memory available.

Memory use with this patch is unchanged.  Code size is increased by:

   bare-arm:  +136
minimal x86:  +124
   unix x64:   +72
unix nanbox:   +96
      stm32:   +88
    esp8266:   +92
     cc3200:   +80
2017-09-21 15:24:57 +10:00
Damien George 34d0b3f85c tests/micropython: Add tests for heap_lock, and emergency exceptions. 2016-10-14 00:32:34 +11:00