Move libnbaio out of AudioFlinger
libnbaio is now a separate shared library from AudioFlinger, rather
than a static library used only by AudioFlinger.
AudioBufferProvider interface is now also independent of AudioFlinger,
moved to include/media/
Change-Id: I9bb62ffbc38d42a38b0af76e66da5e9ab1e0e21b
diff --git a/media/libnbaio/Pipe.cpp b/media/libnbaio/Pipe.cpp
new file mode 100644
index 0000000..1c21f9c
--- /dev/null
+++ b/media/libnbaio/Pipe.cpp
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "Pipe"
+//#define LOG_NDEBUG 0
+
+#include <cutils/atomic.h>
+#include <cutils/compiler.h>
+#include <utils/Log.h>
+#include <media/nbaio/Pipe.h>
+#include <media/nbaio/roundup.h>
+
+namespace android {
+
+Pipe::Pipe(size_t maxFrames, NBAIO_Format format) :
+ NBAIO_Sink(format),
+ mMaxFrames(roundup(maxFrames)),
+ mBuffer(malloc(mMaxFrames * Format_frameSize(format))),
+ mRear(0),
+ mReaders(0)
+{
+}
+
+Pipe::~Pipe()
+{
+ ALOG_ASSERT(android_atomic_acquire_load(&mReaders) == 0);
+ free(mBuffer);
+}
+
+ssize_t Pipe::write(const void *buffer, size_t count)
+{
+ // count == 0 is unlikely and not worth checking for
+ if (CC_UNLIKELY(!mNegotiated)) {
+ return NEGOTIATE;
+ }
+ // write() is not multi-thread safe w.r.t. itself, so no mutex or atomic op needed to read mRear
+ size_t rear = mRear & (mMaxFrames - 1);
+ size_t written = mMaxFrames - rear;
+ if (CC_LIKELY(written > count)) {
+ written = count;
+ }
+ memcpy((char *) mBuffer + (rear << mBitShift), buffer, written << mBitShift);
+ if (CC_UNLIKELY(rear + written == mMaxFrames)) {
+ if (CC_UNLIKELY((count -= written) > rear)) {
+ count = rear;
+ }
+ if (CC_LIKELY(count > 0)) {
+ memcpy(mBuffer, (char *) buffer + (written << mBitShift), count << mBitShift);
+ written += count;
+ }
+ }
+ android_atomic_release_store(written + mRear, &mRear);
+ mFramesWritten += written;
+ return written;
+}
+
+} // namespace android