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authorTaybin Rutkin <taybin@taybin.com>2006-06-29 22:21:30 +0000
committerTaybin Rutkin <taybin@taybin.com>2006-06-29 22:21:30 +0000
commit481f7c39655afec832ac10430dd61a3bb464aa58 (patch)
treecde736699cbe49374a6aaa079258f88c1d0c7059 /libs/pbd/pbd/ringbufferNPT.h
parentd1a4f74ef2c86042a0cbe0e83e611596df27575f (diff)
Fixed i18n system.
Renamed pbd3 back to pbd, since it's version 4.1 now. Very minor fixes git-svn-id: svn://localhost/ardour2/trunk@656 d708f5d6-7413-0410-9779-e7cbd77b26cf
Diffstat (limited to 'libs/pbd/pbd/ringbufferNPT.h')
-rw-r--r--libs/pbd/pbd/ringbufferNPT.h275
1 files changed, 275 insertions, 0 deletions
diff --git a/libs/pbd/pbd/ringbufferNPT.h b/libs/pbd/pbd/ringbufferNPT.h
new file mode 100644
index 0000000000..fee2efce3d
--- /dev/null
+++ b/libs/pbd/pbd/ringbufferNPT.h
@@ -0,0 +1,275 @@
+/*
+ Copyright (C) 2000 Paul Davis & Benno Senoner
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ $Id$
+*/
+
+#ifndef ringbuffer_npt_h
+#define ringbuffer_npt_h
+
+//#include <sys/mman.h>
+
+#include <glib.h>
+
+/* ringbuffer class where the element size is not required to be a power of two */
+
+template<class T>
+class RingBufferNPT
+{
+ public:
+ RingBufferNPT (size_t sz) {
+ size = sz;
+ buf = new T[size];
+ reset ();
+
+ };
+
+ virtual ~RingBufferNPT() {
+ delete [] buf;
+ }
+
+ void reset () {
+ /* !!! NOT THREAD SAFE !!! */
+ g_atomic_int_set (&write_ptr, 0);
+ g_atomic_int_set (&read_ptr, 0);
+ }
+
+ void set (size_t r, size_t w) {
+ /* !!! NOT THREAD SAFE !!! */
+ g_atomic_int_set (&write_ptr, w);
+ g_atomic_int_set (&read_ptr, r);
+ }
+
+ size_t read (T *dest, size_t cnt);
+ size_t write (T *src, size_t cnt);
+
+ struct rw_vector {
+ T *buf[2];
+ size_t 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);
+ }
+
+ void increment_read_ptr (size_t cnt) {
+ g_atomic_int_set (&read_ptr, (g_atomic_int_get(&read_ptr) + cnt) % size);
+ }
+
+ void increment_write_ptr (size_t cnt) {
+ g_atomic_int_set (&write_ptr, (g_atomic_int_get(&write_ptr) + cnt) % size);
+ }
+
+ size_t write_space () {
+ size_t w, r;
+
+ w = g_atomic_int_get (&write_ptr);
+ r = g_atomic_int_get (&read_ptr);
+
+ if (w > r) {
+ return ((r - w + size) % size) - 1;
+ } else if (w < r) {
+ return (r - w) - 1;
+ } else {
+ return size - 1;
+ }
+ }
+
+ size_t read_space () {
+ size_t w, r;
+
+ w = g_atomic_int_get (&write_ptr);
+ r = g_atomic_int_get (&read_ptr);
+
+ if (w > r) {
+ return w - r;
+ } else {
+ return (w - r + size) % size;
+ }
+ }
+
+ 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; }
+
+ protected:
+ T *buf;
+ size_t size;
+ mutable gint write_ptr;
+ mutable gint read_ptr;
+};
+
+template<class T> size_t
+RingBufferNPT<T>::read (T *dest, size_t cnt)
+{
+ size_t free_cnt;
+ size_t cnt2;
+ size_t to_read;
+ size_t n1, n2;
+ size_t priv_read_ptr;
+
+ priv_read_ptr=g_atomic_int_get(&read_ptr);
+
+ if ((free_cnt = read_space ()) == 0) {
+ return 0;
+ }
+
+ to_read = cnt > free_cnt ? free_cnt : cnt;
+
+ cnt2 = priv_read_ptr + to_read;
+
+ if (cnt2 > size) {
+ n1 = size - priv_read_ptr;
+ n2 = cnt2 % size;
+ } else {
+ n1 = to_read;
+ n2 = 0;
+ }
+
+ memcpy (dest, &buf[priv_read_ptr], n1 * sizeof (T));
+ priv_read_ptr = (priv_read_ptr + n1) % size;
+
+ if (n2) {
+ memcpy (dest+n1, buf, n2 * sizeof (T));
+ priv_read_ptr = n2;
+ }
+
+ g_atomic_int_set(&read_ptr, priv_read_ptr);
+ return to_read;
+}
+
+template<class T> size_t
+RingBufferNPT<T>::write (T *src, size_t cnt)
+{
+ size_t free_cnt;
+ size_t cnt2;
+ size_t to_write;
+ size_t n1, n2;
+ size_t priv_write_ptr;
+
+ priv_write_ptr=g_atomic_int_get(&write_ptr);
+
+ if ((free_cnt = write_space ()) == 0) {
+ return 0;
+ }
+
+ to_write = cnt > free_cnt ? free_cnt : cnt;
+
+ cnt2 = priv_write_ptr + to_write;
+
+ if (cnt2 > size) {
+ n1 = size - priv_write_ptr;
+ n2 = cnt2 % size;
+ } else {
+ n1 = to_write;
+ n2 = 0;
+ }
+
+ memcpy (&buf[priv_write_ptr], src, n1 * sizeof (T));
+ priv_write_ptr = (priv_write_ptr + n1) % size;
+
+ if (n2) {
+ memcpy (buf, src+n1, n2 * sizeof (T));
+ priv_write_ptr = n2;
+ }
+
+ g_atomic_int_set(&write_ptr, priv_write_ptr);
+ return to_write;
+}
+
+template<class T> void
+RingBufferNPT<T>::get_read_vector (RingBufferNPT<T>::rw_vector *vec)
+{
+ size_t free_cnt;
+ size_t cnt2;
+ size_t w, r;
+
+ w = g_atomic_int_get (&write_ptr);
+ r = g_atomic_int_get (&read_ptr);
+
+ if (w > r) {
+ free_cnt = w - r;
+ } else {
+ free_cnt = (w - r + size) % size;
+ }
+
+ cnt2 = r + free_cnt;
+
+ if (cnt2 > size) {
+ /* Two part vector: the rest of the buffer after the
+ current write ptr, plus some from the start of
+ the buffer.
+ */
+
+ vec->buf[0] = &buf[r];
+ vec->len[0] = size - r;
+ vec->buf[1] = buf;
+ vec->len[1] = cnt2 % size;
+
+ } else {
+
+ /* Single part vector: just the rest of the buffer */
+
+ vec->buf[0] = &buf[r];
+ vec->len[0] = free_cnt;
+ vec->len[1] = 0;
+ }
+}
+
+template<class T> void
+RingBufferNPT<T>::get_write_vector (RingBufferNPT<T>::rw_vector *vec)
+{
+ size_t free_cnt;
+ size_t cnt2;
+ size_t w, r;
+
+ w = g_atomic_int_get (&write_ptr);
+ r = g_atomic_int_get (&read_ptr);
+
+ if (w > r) {
+ free_cnt = ((r - w + size) % size) - 1;
+ } else if (w < r) {
+ free_cnt = (r - w) - 1;
+ } else {
+ free_cnt = size - 1;
+ }
+
+ cnt2 = w + free_cnt;
+
+ if (cnt2 > size) {
+
+ /* Two part vector: the rest of the buffer after the
+ current write ptr, plus some from the start of
+ the buffer.
+ */
+
+ vec->buf[0] = &buf[w];
+ vec->len[0] = size - w;
+ vec->buf[1] = buf;
+ vec->len[1] = cnt2 % size;
+ } else {
+ vec->buf[0] = &buf[w];
+ vec->len[0] = free_cnt;
+ vec->len[1] = 0;
+ }
+}
+
+#endif /* __ringbuffer_npt_h__ */