libui: add the Fence class
This change adds the Fence class to libui for to wrap the libsync
functionality.
Change-Id: I93a31baeee608b93c14da807a32013dabf783f84
diff --git a/include/ui/Fence.h b/include/ui/Fence.h
new file mode 100644
index 0000000..19d1830
--- /dev/null
+++ b/include/ui/Fence.h
@@ -0,0 +1,94 @@
+/*
+ * 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.
+ */
+
+#ifndef ANDROID_FENCE_H
+#define ANDROID_FENCE_H
+
+#include <stdint.h>
+#include <limits.h>
+#include <sys/types.h>
+
+#include <ui/ANativeObjectBase.h>
+#include <ui/PixelFormat.h>
+#include <ui/Rect.h>
+#include <utils/Flattenable.h>
+#include <utils/String8.h>
+
+struct ANativeWindowBuffer;
+
+namespace android {
+
+// ===========================================================================
+// Fence
+// ===========================================================================
+
+class Fence
+ : public LightRefBase<Fence>, public Flattenable
+{
+public:
+
+ // Construct a new Fence object with an invalid file descriptor. This
+ // should be done when the Fence object will be set up by unflattening
+ // serialized data.
+ Fence();
+
+ // Construct a new Fence object to manage a given fence file descriptor.
+ // When the new Fence object is destructed the file descriptor will be
+ // closed.
+ Fence(int fenceFd);
+
+ // wait waits for up to timeout milliseconds for the fence to signal. If
+ // the fence signals then NO_ERROR is returned. If the timeout expires
+ // before the fence signals then -ETIME is returned. A timeout of
+ // TIMEOUT_NEVER may be used to indicate that the call should wait
+ // indefinitely for the fence to signal.
+ int wait(unsigned int timeout);
+
+ // TIMEOUT_NEVER may be passed to the wait method to indicate that it
+ // should wait indefinitely for the fence to signal.
+ enum { TIMEOUT_NEVER = UINT_MAX };
+
+ // merge combines two Fence objects, creating a new Fence object that
+ // becomes signaled when both f1 and f2 are signaled (even if f1 or f2 is
+ // destroyed before it becomes signaled). The name argument specifies the
+ // human-readable name to associated with the new Fence object.
+ static sp<Fence> merge(const String8& name, const sp<Fence>& f1,
+ const sp<Fence>& f2);
+
+ // Flattenable interface
+ size_t getFlattenedSize() const;
+ size_t getFdCount() const;
+ status_t flatten(void* buffer, size_t size,
+ int fds[], size_t count) const;
+ status_t unflatten(void const* buffer, size_t size,
+ int fds[], size_t count);
+
+private:
+ // Only allow instantiation using ref counting.
+ friend class LightRefBase<Fence>;
+ virtual ~Fence();
+
+ // Disallow copying
+ Fence(const Fence& rhs);
+ Fence& operator = (const Fence& rhs);
+ const Fence& operator = (const Fence& rhs) const;
+
+ int mFenceFd;
+};
+
+}; // namespace android
+
+#endif // ANDROID_FENCE_H
diff --git a/libs/ui/Fence.cpp b/libs/ui/Fence.cpp
new file mode 100644
index 0000000..993585b
--- /dev/null
+++ b/libs/ui/Fence.cpp
@@ -0,0 +1,95 @@
+/*
+ * 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 "Fence"
+#define ATRACE_TAG ATRACE_TAG_GRAPHICS
+//#define LOG_NDEBUG 0
+
+#include <sync/sync.h>
+#include <ui/Fence.h>
+#include <unistd.h>
+#include <utils/Log.h>
+#include <utils/Trace.h>
+
+namespace android {
+
+Fence::Fence() :
+ mFenceFd(-1) {
+}
+
+Fence::Fence(int fenceFd) :
+ mFenceFd(fenceFd) {
+}
+
+Fence::~Fence() {
+ if (mFenceFd != -1) {
+ close(mFenceFd);
+ }
+}
+
+int Fence::wait(unsigned int timeout) {
+ ATRACE_CALL();
+ if (mFenceFd == -1) {
+ return NO_ERROR;
+ }
+ return sync_wait(mFenceFd, timeout);
+}
+
+sp<Fence> Fence::merge(const String8& name, const sp<Fence>& f1,
+ const sp<Fence>& f2) {
+ ATRACE_CALL();
+ int result = sync_merge(name.string(), f1->mFenceFd, f2->mFenceFd);
+ if (result == -1) {
+ ALOGE("merge: sync_merge returned an error: %s (%d)", strerror(-errno),
+ errno);
+ return sp<Fence>();
+ }
+ return sp<Fence>(new Fence(result));
+}
+
+size_t Fence::getFlattenedSize() const {
+ return 0;
+}
+
+size_t Fence::getFdCount() const {
+ return 1;
+}
+
+status_t Fence::flatten(void* buffer, size_t size, int fds[],
+ size_t count) const {
+ if (size != 0 || count != 1) {
+ return BAD_VALUE;
+ }
+
+ fds[0] = mFenceFd;
+ return NO_ERROR;
+}
+
+status_t Fence::unflatten(void const* buffer, size_t size, int fds[],
+ size_t count) {
+ if (size != 0 || count != 1) {
+ return BAD_VALUE;
+ }
+ if (mFenceFd != -1) {
+ // Don't unflatten if we already have a valid fd.
+ return INVALID_OPERATION;
+ }
+
+ mFenceFd = fds[0];
+ return NO_ERROR;
+}
+
+} // namespace android