HardwareTimer for STM32 (blue pill) board

[Louis91]

I'm trying to implement class function from "hardwareTimer.h" lib. There are two versions of the function:

"void hardwareTimer::attachInterrupt(int channel, void (*handler)(void))"
"void hardwareTimer::attachInterrupt(int channel, std::function<void(void)>)"

I'm not sure if they are same. Question is, how to write handler function outside of the class that would work with thesse attachInterrupt() functions?

[helios]

I'm not sure if they are same.

They're clearly not.

Question is, how to write handler function outside of the class that would work with thesse attachInterrupt() functions?

I imagine it's something like

void some_simple_handler(){
    //do something
}

ht.attachInterrupt(channel, some_simple_handler);
auto some_object = std::make_shared<Foo>();
ht.attachInterrupt(channel + 1, [some_object](){
    //do something using some_object
});

[mbozzi]

Watch out, since it's possible to leak some_object using the above, depending on what happens inside attachInterrupt.

[helios]

Is it? With a shared_ptr? What could it do to leak it?

[mbozzi]

It's probably not going to be lost forever, unless something silly happens. But the shared_ptr might be cached inside some library data structure for an unknown length of time.

[Louis91]

For platform I am using (Arduino IDE) std::make_shared<>() doesn't work. This is what I tried to do

#include <HardwareTimer.h>

HardwareTimer T1(TIM1);

void handler(void){/*do something*/}

void setup(){
  T1.pause();  // Disable all microcontroler's counters
  // Set timer1 to run handler function every 100ms
  T1.setOverflow(10, HERTZ_FORMAT);
  T1.attachInterrupt(channel, handler); // here I have an error 

  T1.resume(); // Resume all counters
}

and my error message looks like this:
invalid conversion from 'void (*)()' to 'void (*)(HardwareTimer*)' [-fpermissive]

I suspect handler function to be in different form because handler function should be of type "std::function<void(void)>". I do not quite understand this type. Can anybody explain it to me? And how I can implement my handler function correctly?