diff options
Diffstat (limited to 'Alc/ringbuffer.c')
| -rw-r--r-- | Alc/ringbuffer.c | 32 |
1 files changed, 17 insertions, 15 deletions
diff --git a/Alc/ringbuffer.c b/Alc/ringbuffer.c index c594331e..02fa857c 100644 --- a/Alc/ringbuffer.c +++ b/Alc/ringbuffer.c @@ -48,7 +48,7 @@ struct ll_ringbuffer { /* Create a new ringbuffer to hold at least `sz' elements of `elem_sz' bytes. * The number of elements is rounded up to the next power of two. */ -ll_ringbuffer_t *ll_ringbuffer_create(size_t sz, size_t elem_sz) +ll_ringbuffer_t *ll_ringbuffer_create(size_t sz, size_t elem_sz, int limit_writes) { ll_ringbuffer_t *rb; size_t power_of_two = 0; @@ -73,8 +73,8 @@ ll_ringbuffer_t *ll_ringbuffer_create(size_t sz, size_t elem_sz) ATOMIC_INIT(&rb->write_ptr, 0); ATOMIC_INIT(&rb->read_ptr, 0); - rb->size = power_of_two; - rb->size_mask = rb->size - 1; + rb->size = limit_writes ? sz : power_of_two; + rb->size_mask = power_of_two - 1; rb->elem_size = elem_sz; return rb; } @@ -90,7 +90,7 @@ void ll_ringbuffer_reset(ll_ringbuffer_t *rb) { ATOMIC_STORE(&rb->write_ptr, 0, almemory_order_release); ATOMIC_STORE(&rb->read_ptr, 0, almemory_order_release); - memset(rb->buf, 0, rb->size*rb->elem_size); + memset(rb->buf, 0, (rb->size_mask+1)*rb->elem_size); } /* Return the number of elements available for reading. This is the number of @@ -107,7 +107,8 @@ size_t ll_ringbuffer_write_space(const ll_ringbuffer_t *rb) { size_t w = ATOMIC_LOAD(&CONST_CAST(ll_ringbuffer_t*,rb)->write_ptr, almemory_order_acquire); size_t r = ATOMIC_LOAD(&CONST_CAST(ll_ringbuffer_t*,rb)->read_ptr, almemory_order_acquire); - return (r-w-1) & rb->size_mask; + w = (r-w-1) & rb->size_mask; + return (w > rb->size) ? rb->size : w; } /* The copying data reader. Copy at most `cnt' elements from `rb' to `dest'. @@ -127,9 +128,9 @@ size_t ll_ringbuffer_read(ll_ringbuffer_t *rb, char *dest, size_t cnt) read_ptr = ATOMIC_LOAD(&rb->read_ptr, almemory_order_relaxed) & rb->size_mask; cnt2 = read_ptr + to_read; - if(cnt2 > rb->size) + if(cnt2 > rb->size_mask+1) { - n1 = rb->size - read_ptr; + n1 = rb->size_mask+1 - read_ptr; n2 = cnt2 & rb->size_mask; } else @@ -168,9 +169,9 @@ size_t ll_ringbuffer_peek(ll_ringbuffer_t *rb, char *dest, size_t cnt) read_ptr = ATOMIC_LOAD(&rb->read_ptr, almemory_order_relaxed) & rb->size_mask; cnt2 = read_ptr + to_read; - if(cnt2 > rb->size) + if(cnt2 > rb->size_mask+1) { - n1 = rb->size - read_ptr; + n1 = rb->size_mask+1 - read_ptr; n2 = cnt2 & rb->size_mask; } else @@ -206,9 +207,9 @@ size_t ll_ringbuffer_write(ll_ringbuffer_t *rb, const char *src, size_t cnt) write_ptr = ATOMIC_LOAD(&rb->write_ptr, almemory_order_relaxed) & rb->size_mask; cnt2 = write_ptr + to_write; - if(cnt2 > rb->size) + if(cnt2 > rb->size_mask+1) { - n1 = rb->size - write_ptr; + n1 = rb->size_mask+1 - write_ptr; n2 = cnt2 & rb->size_mask; } else @@ -257,12 +258,12 @@ void ll_ringbuffer_get_read_vector(const ll_ringbuffer_t *rb, ll_ringbuffer_data free_cnt = (w-r) & rb->size_mask; cnt2 = r + free_cnt; - if(cnt2 > rb->size) + if(cnt2 > rb->size_mask+1) { /* Two part vector: the rest of the buffer after the current write ptr, * plus some from the start of the buffer. */ vec[0].buf = (char*)&rb->buf[r*rb->elem_size]; - vec[0].len = rb->size - r; + vec[0].len = rb->size_mask+1 - r; vec[1].buf = (char*)rb->buf; vec[1].len = cnt2 & rb->size_mask; } @@ -290,14 +291,15 @@ void ll_ringbuffer_get_write_vector(const ll_ringbuffer_t *rb, ll_ringbuffer_dat w &= rb->size_mask; r &= rb->size_mask; free_cnt = (r-w-1) & rb->size_mask; + if(free_cnt > rb->size) free_cnt = rb->size; cnt2 = w + free_cnt; - if(cnt2 > rb->size) + if(cnt2 > rb->size_mask+1) { /* Two part vector: the rest of the buffer after the current write ptr, * plus some from the start of the buffer. */ vec[0].buf = (char*)&rb->buf[w*rb->elem_size]; - vec[0].len = rb->size - w; + vec[0].len = rb->size_mask+1 - w; vec[1].buf = (char*)rb->buf; vec[1].len = cnt2 & rb->size_mask; } |