1 files changed, 113 insertions, 0 deletions
diff --git a/android/WALT/app/src/main/java/org/chromium/latency/walt/TraceLogger.java b/android/WALT/app/src/main/java/org/chromium/latency/walt/TraceLogger.java
new file mode 100644
index 0000000..6fdb8d9
--- /dev/null
+++ b/android/WALT/app/src/main/java/org/chromium/latency/walt/TraceLogger.java
@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+package org.chromium.latency.walt;
+
+import android.content.Context;
+import android.os.Environment;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.OutputStreamWriter;
+import java.text.DecimalFormat;
+import java.util.ArrayList;
+
+/**
+ * Used to log events for Android systrace
+ */
+class TraceLogger {
+
+    private static final Object LOCK = new Object();
+    private static TraceLogger instance;
+
+    private ArrayList<TraceEvent> traceEvents;
+
+    public static TraceLogger getInstance() {
+        synchronized (LOCK) {
+            if (instance == null) {
+                instance = new TraceLogger();
+            }
+            return instance;
+        }
+    }
+
+    private TraceLogger() {
+        traceEvents = new ArrayList<>();
+    }
+
+    public synchronized void log(long startTimeMicros, long finishTimeMicros, String title, String description) {
+        traceEvents.add(new TraceEvent(startTimeMicros, finishTimeMicros, title, description));
+    }
+
+    public String getLogText() {
+        DecimalFormat df = new DecimalFormat(".000000");
+        StringBuilder sb = new StringBuilder();
+        int pid = android.os.Process.myPid();
+        for (TraceEvent e : traceEvents) {
+            sb.append(String.format(
+                    "WALTThread-1234 (%d) [000] ...1 %s: tracing_mark_write: B|%d|%s|description=%s|WALT\n",
+                    pid, df.format(e.startTimeMicros / 1e6), pid, e.title, e.description));
+            sb.append(String.format(
+                    "WALTThread-1234 (%d) [000] ...1 %s: tracing_mark_write: E|%d|%s||WALT\n",
+                    pid, df.format(e.finishTimeMicros / 1e6), pid, e.title));
+        }
+        return sb.toString();
+    }
+
+    void flush(Context context) {
+        SimpleLogger logger = SimpleLogger.getInstance(context);
+        if (!isExternalStorageWritable()) {
+            logger.log("ERROR: could not write systrace logs to file");
+            return;
+        }
+        writeSystraceLogs(context);
+        traceEvents.clear();
+    }
+
+    private void writeSystraceLogs(Context context) {
+        File file = new File(context.getExternalFilesDir(null), "trace.txt");
+        SimpleLogger logger = SimpleLogger.getInstance(context);
+        try {
+            OutputStreamWriter writer = new OutputStreamWriter(new FileOutputStream(file, true));
+            writer.write(getLogText());
+            writer.close();
+            logger.log(String.format("TraceLogger wrote %d events to %s",
+                    traceEvents.size(), file.getAbsolutePath()));
+        } catch (IOException e) {
+            logger.log("ERROR: IOException writing to trace.txt");
+            e.printStackTrace();
+        }
+    }
+
+    private boolean isExternalStorageWritable() {
+        String state = Environment.getExternalStorageState();
+        return Environment.MEDIA_MOUNTED.equals(state);
+    }
+
+    private class TraceEvent {
+        long startTimeMicros;
+        long finishTimeMicros;
+        String title;
+        String description;
+        TraceEvent(long startTimeMicros, long finishTimeMicros, String title, String description) {
+            this.startTimeMicros = startTimeMicros;
+            this.finishTimeMicros = finishTimeMicros;
+            this.title = title;
+            this.description = description;
+        }
+    }
+}