Hello.
I can't get the tricky boundary calculation. Perhaps I'm missing some obvious thing, or maybe it's really some circumvent for a specific case that was not commented.
The current calculation for boundary is:
boundary = buffer_size; while (boundary * 2 <= LONG_MAX - buffer_size) boundary *= 2;
I've checked out some repositories, specially alsa-driver in ALSA git, and I realized this calculation exists at least since 2001. I guess it was Jaroslav who wrote.
Visualization of the calculation (B = buffer_size):
LONG_MAX ------------------------------- ______________/ __/ B * 4 B ______/ B * 2 __/ B
Why isn't a simpler calculation used instead? e.g.:
/* closest multiple of buffer size less or equal LONG_MAX */ boundary = LONG_MAX - LONG_MAX % buffer_size;
LONG_MAX ------------------------------- __________________________/ B * 6
Cheers!
pasquali