Add TrafficStats class to SDK.

This class (a rename of NetStat) provides network byte and packet statistics.
NetStat will be removed separately, to avoid breaking other packages when submitting.

1 files changed, 265 insertions, 0 deletions

diff --git a/core/java/android/net/TrafficStats.java b/core/java/android/net/TrafficStats.java
new file mode 100644
index 0000000..62e9f1f
--- /dev/null
+++ b/core/java/android/net/TrafficStats.java
@@ -0,0 +1,265 @@
+/*
+ * Copyright (C) 2007 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 android.net;
+
+import android.util.Log;
+
+import java.io.File;
+import java.io.RandomAccessFile;
+import java.io.IOException;
+
+/**
+ * Class that provides network traffic statistics.  These statistics include bytes transmitted and
+ * received and network packets transmitted and received, over all interfaces, over the mobile
+ * interface, and on a per-UID basis.
+ * <p>
+ * These statistics may not be available on all platforms.  If the statistics are not supported
+ * by this device, {@link #UNSUPPORTED} will be returned.
+ */
+public class TrafficStats {
+    /**
+     * The return value to indicate that the device does not support the statistic.
+     */
+    public final static int UNSUPPORTED = -1;
+
+    // Logging tag.
+    private final static String TAG = "trafficstats";
+
+    // We pre-create all the File objects so we don't spend a lot of
+    // CPU at runtime converting from Java Strings to byte[] for the
+    // kernel calls.
+    private final static File[] MOBILE_TX_PACKETS = mobileFiles("tx_packets");
+    private final static File[] MOBILE_RX_PACKETS = mobileFiles("rx_packets");
+    private final static File[] MOBILE_TX_BYTES = mobileFiles("tx_bytes");
+    private final static File[] MOBILE_RX_BYTES = mobileFiles("rx_bytes");
+    private final static File SYS_CLASS_NET_DIR = new File("/sys/class/net");
+
+    /**
+     * Get the total number of packets transmitted through the mobile interface.
+     *
+     * @return number of packets.  If the statistics are not supported by this device,
+     * {@link #UNSUPPORTED} will be returned.
+     */
+    public static long getMobileTxPkts() {
+        return getMobileStat(MOBILE_TX_PACKETS);
+    }
+
+    /**
+     * Get the total number of packets received through the mobile interface.
+     *
+     * @return number of packets.  If the statistics are not supported by this device,
+     * {@link #UNSUPPORTED} will be returned.
+     */
+    public static long getMobileRxPkts() {
+        return getMobileStat(MOBILE_RX_PACKETS);
+    }
+
+    /**
+     * Get the total number of bytes transmitted through the mobile interface.
+     *
+     * @return number of bytes.  If the statistics are not supported by this device,
+     * {@link #UNSUPPORTED} will be returned.
+     */
+      public static long getMobileTxBytes() {
+          return getMobileStat(MOBILE_TX_BYTES);
+      }
+
+    /**
+     * Get the total number of bytes received through the mobile interface.
+     *
+     * @return number of bytes.  If the statistics are not supported by this device,
+     * {@link #UNSUPPORTED} will be returned.
+     */
+    public static long getMobileRxBytes() {
+        return getMobileStat(MOBILE_RX_BYTES);
+    }
+
+    /**
+     * Get the total number of packets sent through all network interfaces.
+     *
+     * @return the number of packets.  If the statistics are not supported by this device,
+     * {@link #UNSUPPORTED} will be returned.
+     */
+    public static long getTotalTxPkts() {
+        return getTotalStat("tx_packets");
+    }
+
+    /**
+     * Get the total number of packets received through all network interfaces.
+     *
+     * @return number of packets.  If the statistics are not supported by this device,
+     * {@link #UNSUPPORTED} will be returned.
+     */
+    public static long getTotalRxPkts() {
+        return getTotalStat("rx_packets");
+    }
+
+    /**
+     * Get the total number of bytes sent through all network interfaces.
+     *
+     * @return number of bytes.  If the statistics are not supported by this device,
+     * {@link #UNSUPPORTED} will be returned.
+     */
+    public static long getTotalTxBytes() {
+        return getTotalStat("tx_bytes");
+    }
+
+    /**
+     * Get the total number of bytes received through all network interfaces.
+     *
+     * @return number of bytes.  If the statistics are not supported by this device,
+     * {@link #UNSUPPORTED} will be returned.
+     */
+    public static long getTotalRxBytes() {
+        return getTotalStat("rx_bytes");
+    }
+
+    /**
+     * Get the number of bytes sent through the network for this UID.
+     * The statistics are across all interfaces.
+     *
+     * {@see android.os.Process#myUid()}.
+     *
+     * @param uid The UID of the process to examine.
+     * @return number of bytes.  If the statistics are not supported by this device,
+     * {@link #UNSUPPORTED} will be returned.
+     */
+    public static long getUidTxBytes(int uid) {
+        return getNumberFromFilePath("/proc/uid_stat/" + uid + "/tcp_snd");
+    }
+
+    /**
+     * Get the number of bytes received through the network for this UID.
+     * The statistics are across all interfaces.
+     *
+     * {@see android.os.Process#myUid()}.
+     *
+     * @param uid The UID of the process to examine.
+     * @return number of bytes
+     */
+    public static long getUidRxBytes(int uid) {
+        return getNumberFromFilePath("/proc/uid_stat/" + uid + "/tcp_rcv");
+    }
+
+    /**
+     * Returns the array of two possible File locations for a given
+     * statistic.
+     */
+    private static File[] mobileFiles(String whatStat) {
+        // Note that we stat them at runtime to see which is
+        // available, rather than here, to guard against the files
+        // coming & going later as modules shut down (e.g. airplane
+        // mode) and whatnot.  The runtime stat() isn't expensive compared
+        // to the previous charset conversion that happened before we
+        // were reusing File instances.
+        File[] files = new File[2];
+        files[0] = new File("/sys/class/net/rmnet0/statistics/" + whatStat);
+        files[1] = new File("/sys/class/net/ppp0/statistics/" + whatStat);
+        return files;
+    }
+
+    private static long getTotalStat(String whatStat) {
+        File netdir = new File("/sys/class/net");
+
+        File[] nets = SYS_CLASS_NET_DIR.listFiles();
+        if (nets == null) {
+            return UNSUPPORTED;
+        }
+        long total = 0;
+        StringBuffer strbuf = new StringBuffer();
+        for (File net : nets) {
+            strbuf.append(net.getPath()).append(File.separator).append("statistics")
+                    .append(File.separator).append(whatStat);
+            total += getNumberFromFilePath(strbuf.toString());
+            strbuf.setLength(0);
+        }
+        return total;
+    }
+
+    private static long getMobileStat(File[] files) {
+        for (int i = 0; i < files.length; i++) {
+            File file = files[i];
+            if (!file.exists()) {
+                continue;
+            }
+            try {
+                RandomAccessFile raf = new RandomAccessFile(file, "r");
+                return getNumberFromFile(raf, file.getAbsolutePath());
+            } catch (IOException e) {
+                Log.w(TAG,
+                      "Exception opening TCP statistics file " + file.getAbsolutePath(),
+                      e);
+            }
+        }
+        return UNSUPPORTED;
+    }
+
+    // File will have format <number><newline>
+    private static long getNumberFromFilePath(String filename) {
+        RandomAccessFile raf = getFile(filename);
+        if (raf == null) {
+            return UNSUPPORTED;
+        }
+        return getNumberFromFile(raf, filename);
+    }
+
+    // Private buffer for getNumberFromFile.  Safe for re-use because
+    // getNumberFromFile is synchronized.
+    private final static byte[] buf = new byte[16];
+
+    private static synchronized long getNumberFromFile(RandomAccessFile raf, String filename) {
+        try {
+            raf.read(buf);
+            raf.close();
+        } catch (IOException e) {
+            Log.w(TAG, "Exception getting TCP bytes from " + filename, e);
+            return UNSUPPORTED;
+        } finally {
+            if (raf != null) {
+                try {
+                    raf.close();
+                } catch (IOException e) {
+                    Log.w(TAG, "Exception closing " + filename, e);
+                }
+            }
+        }
+
+        long num = 0L;
+        for (int i = 0; i < buf.length; i++) {
+            if (buf[i] < '0' || buf[i] > '9') {
+                break;
+            }
+            num *= 10;
+            num += buf[i] - '0';
+        }
+        return num;
+    }
+
+    private static RandomAccessFile getFile(String filename) {
+        File f = new File(filename);
+        if (!f.canRead()) {
+            return null;
+        }
+
+        try {
+            return new RandomAccessFile(f, "r");
+        } catch (IOException e) {
+            Log.w(TAG, "Exception opening TCP statistics file " + filename, e);
+            return null;
+        }
+    }
+}