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Allow for queue sizes that are not a power of 2. 

This prevents nasty surprises because this restriction is not mentioned in the configuration files. It also allows better tuning of performance against memory usage.

Traumflug: costs 18 bytes flash, so it's bearable.
This commit is contained in:
Bas Laarhoven 2011-08-13 12:12:57 -07:00 committed by Markus Hitter
parent 1683db7f57
commit 0dd3b7a892
1 changed files with 6 additions and 1 deletions
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7
dda_queue.c
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@ -32,12 +32,17 @@ uint8_t mb_tail = 0;
/// once writing starts in interrupts on a specific slot, the
/// slot will only be modified in interrupts until the slot is
/// is no longer live.
/// The size does not need to be a power of 2 anymore!
DDA movebuffer[MOVEBUFFER_SIZE] __attribute__ ((__section__ (".bss")));
/// check if the queue is completely full
uint8_t queue_full() {
MEMORY_BARRIER();
return (((mb_tail - mb_head - 1) & (MOVEBUFFER_SIZE - 1)) == 0)?255:0;
if (mb_tail > mb_head) {
return ((mb_tail - mb_head - 1) == 0) ? 255 : 0;
} else {
return ((mb_tail + MOVEBUFFER_SIZE - mb_head - 1) == 0) ? 255 : 0;
}
}
/// check if the queue is completely empty