Basic binary event-log helpers
EventLog can be used from SurfaceFlinger to log jank
statistics events to the binary event log.
Change-Id: If0fbbe7d7111f10957697166d37fd0c3418109bb
diff --git a/services/surfaceflinger/EventLog/EventLog.h b/services/surfaceflinger/EventLog/EventLog.h
new file mode 100644
index 0000000..2f1cd9b
--- /dev/null
+++ b/services/surfaceflinger/EventLog/EventLog.h
@@ -0,0 +1,83 @@
+/*
+ * Copyright 2013 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.
+ */
+
+#include <stdint.h>
+#include <utils/Errors.h>
+#include <utils/Singleton.h>
+
+#ifndef ANDROID_SF_EVENTLOG_H
+#define ANDROID_SF_EVENTLOG_H
+
+// ---------------------------------------------------------------------------
+namespace android {
+// ---------------------------------------------------------------------------
+
+class String8;
+
+class EventLog : public Singleton<EventLog> {
+
+public:
+ static void logJank(const String8& window, int32_t value);
+
+protected:
+ EventLog();
+
+private:
+ /*
+ * EventLogBuffer is a helper class to construct an in-memory event log
+ * tag. In this version the buffer is not dynamic, so write operation can
+ * fail if there is not enough space in the temporary buffer.
+ * Once constructed, the buffer can be logger by calling the log()
+ * method.
+ */
+
+ class TagBuffer {
+ enum { STORAGE_MAX_SIZE = 128 };
+ int32_t mPos;
+ int32_t mTag;
+ bool mOverflow;
+ char mStorage[STORAGE_MAX_SIZE];
+ public:
+ TagBuffer(int32_t tag);
+
+ // starts list of items
+ void startList(int8_t count);
+ // terminates the list
+ void endList();
+ // write a 32-bit integer
+ void writeInt32(int32_t value);
+ // write a 64-bit integer
+ void writeInt64(int64_t value);
+ // write a C string
+ void writeString8(const String8& value);
+
+ // outputs the the buffer to the log
+ void log();
+ };
+
+ friend class Singleton<EventLog>;
+ EventLog(const EventLog&);
+ EventLog& operator =(const EventLog&);
+
+ enum { LOGTAG_SF_JANK = 60100 };
+ void doLogJank(const String8& window, int32_t value);
+};
+
+// ---------------------------------------------------------------------------
+}// namespace android
+// ---------------------------------------------------------------------------
+
+#endif /* ANDROID_SF_EVENTLOG_H */