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authorIOhannes m zmölnig <zmoelnig@iem.at>2015-10-14 15:14:38 +0200
committerIOhannes m zmölnig <zmoelnig@iem.at>2015-10-14 15:14:38 +0200
commit28b7e464fd119b8c848753a1f41070422c463c41 (patch)
tree07449abdf85d8f1fd4068839b974242b429720ca /sc4pd/headers/server/MsgFifo.h
parent90c6018a9401e38859f733b3521c919e042322b7 (diff)
parent6932ee2d22511226378218992b0005cb01eb235e (diff)
- abstractions/tb - externals/tb
Diffstat (limited to 'sc4pd/headers/server/MsgFifo.h')
-rw-r--r--sc4pd/headers/server/MsgFifo.h169
1 files changed, 169 insertions, 0 deletions
diff --git a/sc4pd/headers/server/MsgFifo.h b/sc4pd/headers/server/MsgFifo.h
new file mode 100644
index 0000000..cdc8578
--- /dev/null
+++ b/sc4pd/headers/server/MsgFifo.h
@@ -0,0 +1,169 @@
+/*
+ SuperCollider real time audio synthesis system
+ Copyright (c) 2002 James McCartney. All rights reserved.
+ http://www.audiosynth.com
+
+ 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#ifndef _MsgFifo_
+#define _MsgFifo_
+
+#ifdef SC_DARWIN
+# include <CoreServices/CoreServices.h>
+#endif
+
+/////////////////////////////////////////////////////////////////////
+
+template <class MsgType, int N>
+class MsgFifo
+{
+public:
+ MsgFifo()
+ : mReadHead(0), mWriteHead(0), mFreeHead(0)
+ {}
+
+ void MakeEmpty() { mFreeHead = mReadHead = mWriteHead; }
+ bool IsEmpty() { return mReadHead == mWriteHead; }
+ bool HasData() { return mReadHead != mWriteHead; }
+ bool NeedsFree() { return mFreeHead != mReadHead; }
+
+ bool Write(MsgType& data)
+ {
+ unsigned int next = NextPos(mWriteHead);
+ if (next == mFreeHead) return false; // fifo is full
+ mItems[next] = data;
+#ifdef SC_DARWIN
+ // we don't really need a compare and swap, but this happens to call
+ // the PowerPC memory barrier instruction lwsync.
+ CompareAndSwap(mWriteHead, next, &mWriteHead);
+#elif defined SC_WIN32
+ InterlockedExchange(reinterpret_cast<volatile LONG*>(&mWriteHead),next);
+#else
+ mWriteHead = next;
+#endif
+ return true;
+ }
+
+ void Perform() // get next and advance
+ {
+ while (HasData()) {
+ unsigned int next = NextPos(mReadHead);
+ mItems[next].Perform();
+#ifdef SC_DARWIN
+ // we don't really need a compare and swap, but this happens to call
+ // the PowerPC memory barrier instruction lwsync.
+ CompareAndSwap(mReadHead, next, &mReadHead);
+#elif defined SC_WIN32
+ InterlockedExchange(reinterpret_cast<volatile LONG*>(&mReadHead),next);
+#else
+ mReadHead = next;
+#endif
+ }
+ }
+ void Free() // reclaim messages
+ {
+ while (NeedsFree()) {
+ unsigned int next = NextPos(mFreeHead);
+ mItems[next].Free();
+#ifdef SC_DARWIN
+ // we don't really need a compare and swap, but this happens to call
+ // the PowerPC memory barrier instruction lwsync.
+ CompareAndSwap(mFreeHead, next, &mFreeHead);
+#elif defined SC_WIN32
+ InterlockedExchange(reinterpret_cast<volatile LONG*>(&mFreeHead),next);
+#else
+ mFreeHead = next;
+#endif
+ }
+ }
+
+private:
+ int NextPos(int inPos) { return (inPos + 1) & (N - 1); }
+
+#ifdef SC_DARWIN
+ UInt32 mReadHead, mWriteHead, mFreeHead;
+#else
+ volatile unsigned int mReadHead, mWriteHead, mFreeHead;
+#endif
+ MsgType mItems[N];
+};
+
+/////////////////////////////////////////////////////////////////////
+
+template <class MsgType, int N>
+class MsgFifoNoFree
+{
+public:
+ MsgFifoNoFree()
+ : mReadHead(0), mWriteHead(0)
+ {
+ }
+
+ void MakeEmpty() { mReadHead = mWriteHead; }
+ bool IsEmpty() { return mReadHead == mWriteHead; }
+ bool HasData() { return mReadHead != mWriteHead; }
+
+ bool Write(MsgType& data)
+ {
+ unsigned int next = NextPos(mWriteHead);
+ if (next == mReadHead) return false; // fifo is full
+ mItems[next] = data;
+#ifdef SC_DARWIN
+ // we don't really need a compare and swap, but this happens to call
+ // the PowerPC memory barrier instruction lwsync.
+ CompareAndSwap(mWriteHead, next, &mWriteHead);
+#elif defined SC_WIN32
+ InterlockedExchange(reinterpret_cast<volatile LONG*>(&mWriteHead),next);
+#else
+ mWriteHead = next;
+#endif
+ return true;
+ }
+
+ void Perform() // get next and advance
+ {
+ while (HasData()) {
+ unsigned int next = NextPos(mReadHead);
+ mItems[next].Perform();
+#ifdef SC_DARWIN
+ // we don't really need a compare and swap, but this happens to call
+ // the PowerPC memory barrier instruction lwsync.
+ CompareAndSwap(mReadHead, next, &mReadHead);
+#elif defined SC_WIN32
+ InterlockedExchange(reinterpret_cast<volatile LONG*>(&mReadHead),next);
+#else
+ mReadHead = next;
+#endif
+ }
+ }
+
+private:
+ int NextPos(int inPos) { return (inPos + 1) & (N - 1); }
+
+#ifdef SC_DARWIN
+ UInt32 mReadHead, mWriteHead;
+#else
+ volatile unsigned int mReadHead, mWriteHead;
+#endif
+ MsgType mItems[N];
+};
+
+/////////////////////////////////////////////////////////////////////
+
+
+#endif
+
+