restore static_assert

libraries/Ticker/src/Ticker.h

@@ -97,28 +97,26 @@ class Ticker
  _attach(Milliseconds(milliseconds), true);
  }
 
+ // use function pointer directly. SDK used for argument storage, so we don't support anything larger than 4 bytes
+ template <typename T>
+ using callback_with_typed_arg_t = void(*)(T);
+
  // instead of copying the callback function, store function pointer and it's argument
  // callback will still be called in SYS ctx when ticker fires in N seconds
- template <typename TArg, typename Callback = void(*)(TArg)>
- void attach(float seconds, Callback callback, TArg arg)
+ template <typename T>
+ void attach(float seconds, callback_with_typed_arg_t<T> callback, T arg)
  {
- _callback = callback_ptr_t{
- .func = reinterpret_cast<callback_with_arg_t>(callback),
- .arg = reinterpret_cast<void*>(arg),
- };
+ _callback = callback_ptr_t(callback, arg);
  _attach(Seconds(seconds), true);
  }
 
  // instead of copying the callback function, store function pointer and it's argument
- // (that may not be larger than the size of the pointer aka 4bytes)
+ // (that **cannot** be larger than the size of the pointer - 4 bytes)
  // callback will still be called in SYS ctx when ticker fires in N milliseconds
- template <typename TArg, typename Callback = void(*)(TArg)>
- void attach_ms(uint32_t milliseconds, Callback callback, TArg arg)
+ template <typename T>
+ void attach_ms(uint32_t milliseconds, callback_with_typed_arg_t<T> callback, T arg)
  {
- _callback = callback_ptr_t{
- .func = reinterpret_cast<callback_with_arg_t>(callback),
- .arg = reinterpret_cast<void*>(arg),
- };
+ _callback = callback_ptr_t(callback, arg);
  _attach(Milliseconds(milliseconds), true);
  }
 
@@ -151,24 +149,18 @@ class Ticker
  }
 
  // callback will be called in SYS ctx when ticker fires
- template <typename TArg, typename Callback = void(*)(TArg)>
- void once(float seconds, Callback callback, TArg arg)
+ template <typename T>
+ void once(float seconds, callback_with_typed_arg_t<T> callback, T arg)
  {
- _callback = callback_ptr_t{
- .func = reinterpret_cast<callback_with_arg_t>(callback),
- .arg = reinterpret_cast<void*>(arg),
- };
+ _callback = callback_ptr_t(callback, arg);
  _attach(Seconds(seconds), false);
  }
 
  // callback will be called in SYS ctx when ticker fires
- template <typename TArg, typename Callback = void(*)(TArg)>
- void once_ms(uint32_t milliseconds, Callback callback, TArg arg)
+ template <typename T>
+ void once_ms(uint32_t milliseconds, callback_with_typed_arg_t<T> callback, T arg)
  {
- _callback = callback_ptr_t{
- .func = reinterpret_cast<callback_with_arg_t>(callback),
- .arg = reinterpret_cast<void*>(arg),
- };
+ _callback = callback_ptr_t(callback, arg);
  _attach(Milliseconds(milliseconds), false);
  }
 
@@ -212,6 +204,14 @@ class Ticker
 private:
  struct callback_ptr_t
  {
+ template <typename T>
+ callback_ptr_t(callback_with_typed_arg_t<T> func, T arg) :
+ func(reinterpret_cast<callback_with_arg_t>(func)),
+ arg(reinterpret_cast<void*>(arg))
+ {
+ static_assert(sizeof(T) <= sizeof(void*), "");
+ }
+
  callback_with_arg_t func = nullptr;
  void* arg = nullptr;
  };