The code conventions suggest using header guards, but do not define how
those should look like and instead point to existing files. However, not
all existing files follow the same scheme, sometimes omitting header guards
altogether, sometimes using non-standard names, making it easy to
accidentally pick a "wrong" example.
This commit ensures that all header files of the MicroPython project (that
were not simply copied from somewhere else) follow the same pattern, that
was already present in the majority of files, especially in the py folder.
The rules are as follows.
Naming convention:
* start with the words MICROPY_INCLUDED
* contain the full path to the file
* replace special characters with _
In addition, there are no empty lines before #ifndef, between #ifndef and
one empty line before #endif. #endif is followed by a comment containing
the name of the guard macro.
py/grammar.h cannot use header guards by design, since it has to be
included multiple times in a single C file. Several other files also do not
need header guards as they are only used internally and guaranteed to be
included only once:
* MICROPY_MPHALPORT_H
* mpconfigboard.h
* mpconfigport.h
* mpthreadport.h
* pin_defs_*.h
* qstrdefs*.h
This allows to use the On-Chip retention registers for both the
RTC and to share notification flags between the bootloader and the
application. The two flags being shared right now are the "safe boot"
request and the WDT reset cause. we still have 2 more bits free for
future use.
The safe boot pin, when pulled high during reset rolls back the
firmware to the "factory" image and skips execution of 'boot.py'
and 'main.py'. This is useful to recover from a crash condition.
The system led is used mostly to signal errors.
The port currently implements support for GPIO, RTC, ExtInt and the WiFi
subsystem. A small file system is available in the serial flash. A
bootloader which makes OTA updates possible, is also part of this initial
implementation.