For certain basic functionality, there aren't much benefit to be able to
vary the implementation easily at runtime. So instead of using virtual
functions, use regular functions that are "resolved" at link time. The
implementation of such functions is provided per board/platform.
Examples of functions that fit this include: getting the current
time (since boot), panic'ing, getting system information, rebooting.
These functions are less likely to benefit from the indirection provided
by virtual interfaces. For more complex hardware access APIs the
indirection makes more sense and ease the testing (when we have it!).
The idea is that instead of calling
hal.scheduler->panic("on the streets of london");
now use
AP_HAL::panic("on the streets of london");
A less important side-effect is that call-site code gets
smaller. Currently the compiler needs to get the hal, get the scheduler
pointer, get the right function pointer in the vtable for that
scheduler. And the call must include an extra parameter ("this"). Now it
will be just a function call, with the address resolved at link time.
This patch introduces the first functions that will be in the namespace,
further patches will implementations for each board and then switch the
call-sites. The extra init() function allow any initial setup needed for
the functions to work.
Remove the checks for HAL_CPU_CLASS > HAL_CPU_CLASS_16 and
HAL_CPU_CLASS >= HAL_CPU_CLASS_75. Corresponding dead code will be
removed on separate commits.
Most of AP_Progmem is already gone so we can stop including it in most
of the places. The only places that need it are the ones using
pgm_read_*() APIs.
In some cases the header needed to be added in the .cpp since it was
removed from the .h to reduce scope. In those cases the headers were
also reordered.
prog_char and prog_char_t are now the same as char on supported
platforms. So, just change all places that use them and prefer char
instead.
AVR-specific places were not changed.
Now variables don't have to be declared with PROGMEM anymore, so remove
them. This was automated with:
git grep -l -z PROGMEM | xargs -0 sed -i 's/ PROGMEM / /g'
git grep -l -z PROGMEM | xargs -0 sed -i 's/PROGMEM//g'
The 2 commands were done so we don't leave behind spurious spaces.
AVR-specific places were not changed.
The PSTR is already define as a NOP for all supported platforms. It's
only needed for AVR so here we remove all the uses throughout the
codebase.
This was automated with a simple python script so it also converts
places which spans to multiple lines, removing the matching parentheses.
AVR-specific places were not changed.
Follow the following order for includes:
- Corresponding header file (if exists)
- System headers
- Other ArduPilot library headers
- "Local" headers (from the same library)
This was introduced with the HAL rework:
In file included from /p/ardupilot/libraries/AP_HAL/AP_HAL.h:11:0,
from /p/ardupilot/ArduCopter/Copter.h:35,
from /p/ardupilot/ArduCopter/ArduCopter.cpp:76:
/p/ardupilot/ArduCopter/ArduCopter.cpp: In function 'int ArduPilot_main(int, char* const*)':
/p/ardupilot/libraries/AP_HAL/AP_HAL_Main.h:11:26: warning: no previous declaration for 'int ArduPilot_main(int, char* const*)' [-Wmissing-declarations]
#define AP_MAIN __EXPORT ArduPilot_main
^
It's due to PX4 using that warning as opposed to Linux. Since it harmless, add
the prototype for everybody.
Since we are using uint8_t and uint16_t types we need to include the
correspondent system header. Otherwise it would depend on the include
order of who is including this particular header, causing failures as we
move headers around.
This is going to be used by vehicles that already have an object with
setup/loop functions. The vehicle object will just implement the
HAL::Callbacks interface.
Move the macros to a single place and reduce the variations not based on
board, but based on
- The name of the entry-point function, specified by AP_MAIN;
- Whether it contains argc/argv arguments or not.
The goal here is that programs (vehicles and examples) don't need to
include all possible boards to define a main function. Further patches
will change the programs.
Add run method, that encapsulate any mainloop logic on behalf of the
client code. The setup/loop functions are passed via a HAL::Callbacks
interface. The AP_HAL_MAIN() macro should be kept as trivial as
possible.
This interface should be implemented by the existing vehicle objects. To
make easy for the examples (that don't have the equivalent of vehicle
objects), a FunCallbacks was added to bridge to the functions directly.
Instead of requiring every program to specify the HAL related modules,
let the build system do it (in practice everything we compiled depended
on HAL anyway). This allow including only the necessary files in the
compilation.
The switching between different AP_HAL was happening by giving different
definitions of AP_HAL_BOARD_DRIVER, and the programs would use it to
instantiate.
A program or library code would have to explicitly include (and depend)
on the concrete implementation of the HAL, even when using it only via
interface.
The proposed change move this dependency to be link time. There is a
AP_HAL::get_HAL() function that is used by the client code. Each
implementation of HAL provides its own definition of this function,
returning the appropriate concrete instance.
Since this replaces the job of AP_HAL_BOARD_DRIVER, the definition was
removed.
The static variables for PX4 and VRBRAIN were named differently to avoid
shadowing the extern symbol 'hal'.
This method is not used anymore since the introduction of channel map and
allowing motors to be enabled/disabled in AP_Motors.
Later we may introduce a method to write multiple values with a default
implementation that supports the channel and enable maps rather than
requiring all subclasses to implement this method.
Caio Marcelo de Oliveira Filho
Andrew Tridgell
José Roberto de Souza
Víctor Mayoral Vilches
Lucas De Marchi
Julien BERAUD
mirkix
raspilot
Gustavo Jose de Sousa