diff options
Diffstat (limited to 'libs/pbd/pbd/ringbuffer.h')
| -rw-r--r-- | libs/pbd/pbd/ringbuffer.h | 146 |
1 files changed, 71 insertions, 75 deletions
diff --git a/libs/pbd/pbd/ringbuffer.h b/libs/pbd/pbd/ringbuffer.h index 1d9c9b04e3..d98601461e 100644 --- a/libs/pbd/pbd/ringbuffer.h +++ b/libs/pbd/pbd/ringbuffer.h @@ -15,25 +15,21 @@ along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - $Id$ */ #ifndef ringbuffer_h #define ringbuffer_h -//#include <sys/mman.h> - #include <glib.h> template<class T> class RingBuffer { public: - RingBuffer (size_t sz) { - size_t power_of_two; - - for (power_of_two = 1; 1U<<power_of_two < sz; power_of_two++); - + RingBuffer (guint sz) { +// size = ffs(sz); /* find first [bit] set is a single inlined assembly instruction. But it looks like the API rounds up so... */ + guint power_of_two; + for (power_of_two = 1; 1U<<power_of_two < sz; power_of_two++); size = 1<<power_of_two; size_mask = size; size_mask -= 1; @@ -48,44 +44,44 @@ class RingBuffer void reset () { /* !!! NOT THREAD SAFE !!! */ - g_atomic_int_set (&write_ptr, 0); - g_atomic_int_set (&read_ptr, 0); + g_atomic_int_set (&write_idx, 0); + g_atomic_int_set (&read_idx, 0); } - void set (size_t r, size_t w) { + void set (guint r, guint w) { /* !!! NOT THREAD SAFE !!! */ - g_atomic_int_set (&write_ptr, w); - g_atomic_int_set (&read_ptr, r); + g_atomic_int_set (&write_idx, w); + g_atomic_int_set (&read_idx, r); } - size_t read (T *dest, size_t cnt); - size_t write (T *src, size_t cnt); + guint read (T *dest, guint cnt); + guint write (T *src, guint cnt); struct rw_vector { T *buf[2]; - size_t len[2]; + guint len[2]; }; void get_read_vector (rw_vector *); void get_write_vector (rw_vector *); - void decrement_read_ptr (size_t cnt) { - g_atomic_int_set (&read_ptr, (g_atomic_int_get(&read_ptr) - cnt) & size_mask); + void decrement_read_idx (guint cnt) { + g_atomic_int_set (&read_idx, (g_atomic_int_get(&read_idx) - cnt) & size_mask); } - void increment_read_ptr (size_t cnt) { - g_atomic_int_set (&read_ptr, (g_atomic_int_get(&read_ptr) + cnt) & size_mask); + void increment_read_idx (guint cnt) { + g_atomic_int_set (&read_idx, (g_atomic_int_get(&read_idx) + cnt) & size_mask); } - void increment_write_ptr (size_t cnt) { - g_atomic_int_set (&write_ptr, (g_atomic_int_get(&write_ptr) + cnt) & size_mask); + void increment_write_idx (guint cnt) { + g_atomic_int_set (&write_idx, (g_atomic_int_get(&write_idx) + cnt) & size_mask); } - size_t write_space () { - size_t w, r; + guint write_space () { + guint w, r; - w = g_atomic_int_get (&write_ptr); - r = g_atomic_int_get (&read_ptr); + w = g_atomic_int_get (&write_idx); + r = g_atomic_int_get (&read_idx); if (w > r) { return ((r - w + size) & size_mask) - 1; @@ -96,11 +92,11 @@ class RingBuffer } } - size_t read_space () { - size_t w, r; + guint read_space () { + guint w, r; - w = g_atomic_int_get (&write_ptr); - r = g_atomic_int_get (&read_ptr); + w = g_atomic_int_get (&write_idx); + r = g_atomic_int_get (&read_idx); if (w > r) { return w - r; @@ -110,28 +106,28 @@ class RingBuffer } T *buffer () { return buf; } - size_t get_write_ptr () const { return g_atomic_int_get (&write_ptr); } - size_t get_read_ptr () const { return g_atomic_int_get (&read_ptr); } - size_t bufsize () const { return size; } + guint get_write_idx () const { return g_atomic_int_get (&write_idx); } + guint get_read_idx () const { return g_atomic_int_get (&read_idx); } + guint bufsize () const { return size; } protected: T *buf; - size_t size; - mutable gint write_ptr; - mutable gint read_ptr; - size_t size_mask; + guint size; + mutable gint write_idx; + mutable gint read_idx; + guint size_mask; }; -template<class T> size_t -RingBuffer<T>::read (T *dest, size_t cnt) +template<class T> guint +RingBuffer<T>::read (T *dest, guint cnt) { - size_t free_cnt; - size_t cnt2; - size_t to_read; - size_t n1, n2; - size_t priv_read_ptr; + guint free_cnt; + guint cnt2; + guint to_read; + guint n1, n2; + guint priv_read_idx; - priv_read_ptr=g_atomic_int_get(&read_ptr); + priv_read_idx=g_atomic_int_get(&read_idx); if ((free_cnt = read_space ()) == 0) { return 0; @@ -139,39 +135,39 @@ RingBuffer<T>::read (T *dest, size_t cnt) to_read = cnt > free_cnt ? free_cnt : cnt; - cnt2 = priv_read_ptr + to_read; + cnt2 = priv_read_idx + to_read; if (cnt2 > size) { - n1 = size - priv_read_ptr; + n1 = size - priv_read_idx; n2 = cnt2 & size_mask; } else { n1 = to_read; n2 = 0; } - memcpy (dest, &buf[priv_read_ptr], n1 * sizeof (T)); - priv_read_ptr = (priv_read_ptr + n1) & size_mask; + memcpy (dest, &buf[priv_read_idx], n1 * sizeof (T)); + priv_read_idx = (priv_read_idx + n1) & size_mask; if (n2) { memcpy (dest+n1, buf, n2 * sizeof (T)); - priv_read_ptr = n2; + priv_read_idx = n2; } - g_atomic_int_set(&read_ptr, priv_read_ptr); + g_atomic_int_set(&read_idx, priv_read_idx); return to_read; } -template<class T> size_t -RingBuffer<T>::write (T *src, size_t cnt) +template<class T> guint +RingBuffer<T>::write (T *src, guint cnt) { - size_t free_cnt; - size_t cnt2; - size_t to_write; - size_t n1, n2; - size_t priv_write_ptr; + guint free_cnt; + guint cnt2; + guint to_write; + guint n1, n2; + guint priv_write_idx; - priv_write_ptr=g_atomic_int_get(&write_ptr); + priv_write_idx=g_atomic_int_get(&write_idx); if ((free_cnt = write_space ()) == 0) { return 0; @@ -179,25 +175,25 @@ RingBuffer<T>::write (T *src, size_t cnt) to_write = cnt > free_cnt ? free_cnt : cnt; - cnt2 = priv_write_ptr + to_write; + cnt2 = priv_write_idx + to_write; if (cnt2 > size) { - n1 = size - priv_write_ptr; + n1 = size - priv_write_idx; n2 = cnt2 & size_mask; } else { n1 = to_write; n2 = 0; } - memcpy (&buf[priv_write_ptr], src, n1 * sizeof (T)); - priv_write_ptr = (priv_write_ptr + n1) & size_mask; + memcpy (&buf[priv_write_idx], src, n1 * sizeof (T)); + priv_write_idx = (priv_write_idx + n1) & size_mask; if (n2) { memcpy (buf, src+n1, n2 * sizeof (T)); - priv_write_ptr = n2; + priv_write_idx = n2; } - g_atomic_int_set(&write_ptr, priv_write_ptr); + g_atomic_int_set(&write_idx, priv_write_idx); return to_write; } @@ -205,12 +201,12 @@ template<class T> void RingBuffer<T>::get_read_vector (RingBuffer<T>::rw_vector *vec) { - size_t free_cnt; - size_t cnt2; - size_t w, r; + guint free_cnt; + guint cnt2; + guint w, r; - w = g_atomic_int_get (&write_ptr); - r = g_atomic_int_get (&read_ptr); + w = g_atomic_int_get (&write_idx); + r = g_atomic_int_get (&read_idx); if (w > r) { free_cnt = w - r; @@ -245,12 +241,12 @@ template<class T> void RingBuffer<T>::get_write_vector (RingBuffer<T>::rw_vector *vec) { - size_t free_cnt; - size_t cnt2; - size_t w, r; + guint free_cnt; + guint cnt2; + guint w, r; - w = g_atomic_int_get (&write_ptr); - r = g_atomic_int_get (&read_ptr); + w = g_atomic_int_get (&write_idx); + r = g_atomic_int_get (&read_idx); if (w > r) { free_cnt = ((r - w + size) & size_mask) - 1; |