This is the same approach as done for AP_HAL_Linux in e3d78b8 ("AP_HAL_Linux:
fix passing callback to member function"). It fixes the following warnings:
ardupilot/libraries/AP_HAL_PX4/Scheduler.cpp: In member function 'virtual void PX4::PX4Scheduler::init(void*)':
ardupilot/libraries/AP_HAL_PX4/Scheduler.cpp:55:95: warning: converting from 'void* (PX4::PX4Scheduler::*)()' to 'pthread_startroutine_t {aka void* (*)(void*)}' [-Wpmf-conversions]
pthread_create(&_timer_thread_ctx, &thread_attr, (pthread_startroutine_t)&PX4::PX4Scheduler::_timer_thread, this);
^
ardupilot/libraries/AP_HAL_PX4/Scheduler.cpp:65:94: warning: converting from 'void* (PX4::PX4Scheduler::*)()' to 'pthread_startroutine_t {aka void* (*)(void*)}' [-Wpmf-conversions]
pthread_create(&_uart_thread_ctx, &thread_attr, (pthread_startroutine_t)&PX4::PX4Scheduler::_uart_thread, this);
^
ardupilot/libraries/AP_HAL_PX4/Scheduler.cpp:75:92: warning: converting from 'void* (PX4::PX4Scheduler::*)()' to 'pthread_startroutine_t {aka void* (*)(void*)}' [-Wpmf-conversions]
pthread_create(&_io_thread_ctx, &thread_attr, (pthread_startroutine_t)&PX4::PX4Scheduler::_io_thread, this);
^
ardupilot/libraries/AP_HAL_PX4/Scheduler.cpp:85:100: warning: converting from 'void* (PX4::PX4Scheduler::*)()' to 'pthread_startroutine_t {aka void* (*)(void*)}' [-Wpmf-conversions]
pthread_create(&_storage_thread_ctx, &thread_attr, (pthread_startroutine_t)&PX4::PX4Scheduler::_storage_thread, this);
ardupilot/libraries/AP_HAL_PX4/NSHShellStream.cpp: In member function 'void PX4::NSHShellStream::start_shell()':
ardupilot/libraries/AP_HAL_PX4/NSHShellStream.cpp:83:99: warning: converting from 'void (PX4::NSHShellStream::*)()' to 'pthread_startroutine_t {aka void* (*)(void*)}' [-Wpmf-conversions]
pthread_create(&shell_thread_ctx, &thread_attr, (pthread_startroutine_t)&PX4::NSHShellStream::shell_thread, this);
^
The argument in init() is not used by any implementation. Add a second
method without it so the HAL implementation can used it instead. Later
the unused method will be removed.
We don't need to expose to other libraries how each backend is
implemented. AP_Baro.h is the main header, included by other libraries.
Instead of including each backend in the main header, move them to where
they are needed. Additionally standardize the order and how we include
the headers.
The advantages are:
- Internals of each backend is not exposed outside of the
library
- Faster incremental builds since we don't need to recompile
whoever includes AP_Baro.h because a backend changed
The configuration of MS5637 is different from MS5611 in 2 ways:
- The PROM is of 112 bytes rather than 128
- The CRC is located in the first MSB of the first word, not the
last one
For CRC calculation we also need to zero out the last (missing) word.
This renames _check_crc() to _read_prom(), which returns false when the
PROM doesn't contain valid data. It also makes it virtual so MS5637 can
override it. This also moves the PROM read to be all in the same place
rather than split between the CRC field and coefficient fields. Finally
calculate_crc() is renamed to crc4() to be shorter and add info on what
it does.
On MS5637 we will need to override the method to read and calculate the
PROM's crc. Thus we need a 2-phase init.
It also makes the constructor of AP_Baro_MS56XX protected since only the
derived classes should instantiate the base one.
The problem with the current MIN/MAX macros is that they evaluate twice
the arguments. For example, these cases provide unintended results:
// a is incremented twice
a = MIN(a++, b);
// foo() with side-effects
a = MIN(foo(), b);
The alternative implementation here was provided by Daniel Frenzel using
template function. It doesn't have type safety as std::min and std::max,
but adding type safety would mean to check case by case what would be a
reasonable type and add proper casts. Here the arguments for MIN and MAX
can have different types and the return type is deduced from the
expression in the function.
Inspecting the current callers no place was found with the unintended
results above, but some in which now we don't calculate twice the
parameters will benefit from this new version. Examples:
float velocity_max = MIN(_pos_control.get_speed_xy(), safe_sqrt(0.5f*_pos_control.get_accel_xy()*_radius));
float acro_level_mix = constrain_float(1-MAX(MAX(abs(roll_in), abs(pitch_in)), abs(yaw_in))/4500.0, 0, 1)*ahrs.cos_pitch()
accel_x_cmss = (GRAVITY_MSS * 100) * (-(_ahrs.cos_yaw() * _ahrs.sin_pitch() / MAX(_ahrs.cos_pitch(),0.5f)) - _ahrs.sin_yaw() * _ahrs.sin_roll() / MAX(_ahrs.cos_roll(),0.5f));
track_leash_slack = MIN(_track_leash_length*(leash_z-track_error_z)/leash_z, _track_leash_length*(leash_xy-track_error_xy)/leash_xy);
RC_Channel_aux::move_servo(RC_Channel_aux::k_sprayer_pump, MIN(MAX(ground_speed * _pump_pct_1ms, 100 *_pump_min_pct),10000),0,10000);
The problem with using min() and max() is that they conflict with some
C++ headers. Name the macros in uppercase instead. We may go case by
case later converting them to be typesafe.
Changes generated with:
git ls-files '*.cpp' '*.h' -z | xargs -0 sed -i 's/\([^_[:alnum:]]\)max(/\1MAX(/g'
git ls-files '*.cpp' '*.h' -z | xargs -0 sed -i 's/\([^_[:alnum:]]\)min(/\1MIN(/g'
