diff --git a/core/java/android/net/TrafficStats.java b/core/java/android/net/TrafficStats.java index ad8e2bffbc..0d64dab179 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. *

- * 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 - 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 0000000000..db8fdf2d4b --- /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 +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +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)); +} + +}