Merge "Change TrafficStats to a new JNI implementation." into froyo

1 files changed, 15 insertions, 155 deletions

diff --git a/core/java/android/net/TrafficStats.java b/core/java/android/net/TrafficStats.java
index ad8e2bffbc68..0d64dab179e9 100644
--- a/core/java/android/net/TrafficStats.java
+++ b/core/java/android/net/TrafficStats.java
@@ -23,12 +23,12 @@ 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.
+ * 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.
+ * 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 {
     /**
@@ -36,27 +36,13 @@ public class TrafficStats {
      */
     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 getMobileTxPackets() {
-        return getMobileStat(MOBILE_TX_PACKETS);
-    }
+    public static native long getMobileTxPackets();
 
     /**
      * Get the total number of packets received through the mobile interface.
@@ -64,9 +50,7 @@ public class TrafficStats {
      * @return number of packets.  If the statistics are not supported by this device,
      * {@link #UNSUPPORTED} will be returned.
      */
-    public static long getMobileRxPackets() {
-        return getMobileStat(MOBILE_RX_PACKETS);
-    }
+    public static native long getMobileRxPackets();
 
     /**
      * Get the total number of bytes transmitted through the mobile interface.
@@ -74,9 +58,7 @@ public class TrafficStats {
      * @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);
-      }
+      public static native long getMobileTxBytes();
 
     /**
      * Get the total number of bytes received through the mobile interface.
@@ -84,9 +66,7 @@ public class TrafficStats {
      * @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);
-    }
+    public static native long getMobileRxBytes();
 
     /**
      * Get the total number of packets sent through all network interfaces.
@@ -94,9 +74,7 @@ public class TrafficStats {
      * @return the number of packets.  If the statistics are not supported by this device,
      * {@link #UNSUPPORTED} will be returned.
      */
-    public static long getTotalTxPackets() {
-        return getTotalStat("tx_packets");
-    }
+    public static native long getTotalTxPackets();
 
     /**
      * Get the total number of packets received through all network interfaces.
@@ -104,9 +82,7 @@ public class TrafficStats {
      * @return number of packets.  If the statistics are not supported by this device,
      * {@link #UNSUPPORTED} will be returned.
      */
-    public static long getTotalRxPackets() {
-        return getTotalStat("rx_packets");
-    }
+    public static native long getTotalRxPackets();
 
     /**
      * Get the total number of bytes sent through all network interfaces.
@@ -114,9 +90,7 @@ public class TrafficStats {
      * @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");
-    }
+    public static native long getTotalTxBytes();
 
     /**
      * Get the total number of bytes received through all network interfaces.
@@ -124,9 +98,7 @@ public class TrafficStats {
      * @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");
-    }
+    public static native long getTotalRxBytes();
 
     /**
      * Get the number of bytes sent through the network for this UID.
@@ -138,9 +110,7 @@ public class TrafficStats {
      * @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");
-    }
+    public static native long getUidTxBytes(int uid);
 
     /**
      * Get the number of bytes received through the network for this UID.
@@ -151,115 +121,5 @@ public class TrafficStats {
      * @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;
-        }
-    }
+    public static native long getUidRxBytes(int uid);
 }