Change TrafficStats to a new JNI implementation.
Also change phone's ConnectionStateTrackers to use it directly,
rather than through the INetStat binder interface.
Bug: 2578938
Change-Id: I8858e2609cbec3be845a0ce5178cb03f67e01b41
diff --git a/core/java/android/net/TrafficStats.java b/core/java/android/net/TrafficStats.java
index ad8e2bf..0d64dab 100644
--- a/core/java/android/net/TrafficStats.java
+++ b/core/java/android/net/TrafficStats.java
@@ -23,12 +23,12 @@
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 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 @@
* @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 @@
* @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 @@
* @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 @@
* @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 @@
* @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 @@
* @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 @@
* @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 @@
* @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 @@
* @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);
}
diff --git a/core/jni/android_net_TrafficStats.cpp b/core/jni/android_net_TrafficStats.cpp
new file mode 100644
index 0000000..db8fdf2
--- /dev/null
+++ b/core/jni/android_net_TrafficStats.cpp
@@ -0,0 +1,165 @@
+/*
+ * Copyright (C) 2010 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 "TrafficStats"
+
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <android_runtime/AndroidRuntime.h>
+#include <cutils/logger.h>
+#include <jni.h>
+#include <utils/misc.h>
+#include <utils/Log.h>
+
+namespace android {
+
+// Returns an ASCII decimal number read from the specified file, -1 on error.
+static jlong readNumber(char const* filename) {
+ char buf[80];
+ int fd = open(filename, O_RDONLY);
+ if (fd < 0) {
+ if (errno != ENOENT) LOGE("Can't open %s: %s", filename, strerror(errno));
+ return -1;
+ }
+
+ int len = read(fd, buf, sizeof(buf) - 1);
+ if (len < 0) {
+ LOGE("Can't read %s: %s", filename, strerror(errno));
+ close(fd);
+ return -1;
+ }
+
+ close(fd);
+ buf[len] = '\0';
+ return atoll(buf);
+}
+
+// Return the number from the first file which exists and contains data
+static jlong tryBoth(char const* a, char const* b) {
+ jlong num = readNumber(a);
+ return num >= 0 ? num : readNumber(b);
+}
+
+// Returns the sum of numbers from the specified path under /sys/class/net/*,
+// -1 if no such file exists.
+static jlong readTotal(char const* suffix) {
+ char filename[PATH_MAX] = "/sys/class/net/";
+ DIR *dir = opendir(filename);
+ if (dir == NULL) {
+ LOGE("Can't list %s: %s", filename, strerror(errno));
+ return -1;
+ }
+
+ int len = strlen(filename);
+ jlong total = -1;
+ while (struct dirent *entry = readdir(dir)) {
+ // Skip ., .., and localhost interfaces.
+ if (entry->d_name[0] != '.' && strncmp(entry->d_name, "lo", 2) != 0) {
+ strlcpy(filename + len, entry->d_name, sizeof(filename) - len);
+ strlcat(filename, suffix, sizeof(filename));
+ jlong num = readNumber(filename);
+ if (num >= 0) total = total < 0 ? num : total + num;
+ }
+ }
+
+ closedir(dir);
+ return total;
+}
+
+// Mobile stats get accessed a lot more often than total stats.
+// Note the individual files can come and go at runtime, so we check
+// each file every time (rather than caching which ones exist).
+
+static jlong getMobileTxPackets(JNIEnv* env, jobject clazz) {
+ return tryBoth(
+ "/sys/class/net/rmnet0/statistics/tx_packets",
+ "/sys/class/net/ppp0/statistics/tx_packets");
+}
+
+static jlong getMobileRxPackets(JNIEnv* env, jobject clazz) {
+ return tryBoth(
+ "/sys/class/net/rmnet0/statistics/rx_packets",
+ "/sys/class/net/ppp0/statistics/rx_packets");
+}
+
+static jlong getMobileTxBytes(JNIEnv* env, jobject clazz) {
+ return tryBoth(
+ "/sys/class/net/rmnet0/statistics/tx_bytes",
+ "/sys/class/net/ppp0/statistics/tx_bytes");
+}
+
+static jlong getMobileRxBytes(JNIEnv* env, jobject clazz) {
+ return tryBoth(
+ "/sys/class/net/rmnet0/statistics/rx_bytes",
+ "/sys/class/net/ppp0/statistics/rx_bytes");
+}
+
+// Total stats are read less often, so we're willing to put up
+// with listing the directory and concatenating filenames.
+
+static jlong getTotalTxPackets(JNIEnv* env, jobject clazz) {
+ return readTotal("/statistics/tx_packets");
+}
+
+static jlong getTotalRxPackets(JNIEnv* env, jobject clazz) {
+ return readTotal("/statistics/rx_packets");
+}
+
+static jlong getTotalTxBytes(JNIEnv* env, jobject clazz) {
+ return readTotal("/statistics/tx_bytes");
+}
+
+static jlong getTotalRxBytes(JNIEnv* env, jobject clazz) {
+ return readTotal("/statistics/rx_bytes");
+}
+
+// Per-UID stats require reading from a constructed filename.
+
+static jlong getUidRxBytes(JNIEnv* env, jobject clazz, jint uid) {
+ char filename[80];
+ sprintf(filename, "/proc/uid_stat/%d/tcp_rcv", uid);
+ return readNumber(filename);
+}
+
+static jlong getUidTxBytes(JNIEnv* env, jobject clazz, jint uid) {
+ char filename[80];
+ sprintf(filename, "/proc/uid_stat/%d/tcp_snd", uid);
+ return readNumber(filename);
+}
+
+static JNINativeMethod gMethods[] = {
+ {"getMobileTxPackets", "()J", (void*) getMobileTxPackets},
+ {"getMobileRxPackets", "()J", (void*) getMobileRxPackets},
+ {"getMobileTxBytes", "()J", (void*) getMobileTxBytes},
+ {"getMobileRxBytes", "()J", (void*) getMobileRxBytes},
+ {"getTotalTxPackets", "()J", (void*) getTotalTxPackets},
+ {"getTotalRxPackets", "()J", (void*) getTotalRxPackets},
+ {"getTotalTxBytes", "()J", (void*) getTotalTxBytes},
+ {"getTotalRxBytes", "()J", (void*) getTotalRxBytes},
+ {"getUidTxBytes", "(I)J", (void*) getUidTxBytes},
+ {"getUidRxBytes", "(I)J", (void*) getUidRxBytes},
+};
+
+int register_android_net_TrafficStats(JNIEnv* env) {
+ return AndroidRuntime::registerNativeMethods(env, "android/net/TrafficStats",
+ gMethods, NELEM(gMethods));
+}
+
+}