This commit changes the way libraries headers are included in source files:
- If the header is in the same directory the source belongs to, so the
notation '#include ""' is used with the path relative to the directory
containing the source.
- If the header is outside the directory containing the source, then we use
the notation '#include <>' with the path relative to libraries folder.
Some of the advantages of such approach:
- Only one search path for libraries headers.
- OSs like Windows may have a better lookup time.
The main thread would always be blocked on the semaphore to read the
data from accelerometer and gyroscope. Especially if we have a slow
update of these values in _accumulate() due to the I2C transfer function
taking too much time: the timer thread would never give up the CPU,
causing starvation on the main thread.
This fixes the issue by reducing the critical region using a flip-buffer
so _accumulate() can work on its own copy of the data. Now that the
critical region is smaller, also avoid the semaphore and use a spinlock
instead.
Andrew Tridgell
Gustavo Jose de Sousa
Lucas De Marchi
Jonathan Challinger
Andrew Tridgell
Víctor Mayoral Vilches