Improve TrafficStats UID APIs.

Deprecate transport layer statistics, leaving only the summarized
network layer statistics.

Improve documentation to be clear about layers where measurements
occur, and their behavior since boot.  Under the hood, move to using
xt_qtaguid UID statistics.

Bug: 6818637, 7013662
Change-Id: I9f26992e5fcdebd88c671e5765bd91229e7b0016

1 files changed, 39 insertions, 180 deletions

diff --git a/core/jni/android_net_TrafficStats.cpp b/core/jni/android_net_TrafficStats.cpp
index aa8a58b..bf963de 100644
--- a/core/jni/android_net_TrafficStats.cpp
+++ b/core/jni/android_net_TrafficStats.cpp
@@ -32,17 +32,7 @@
 namespace android {
 
 static const char* QTAGUID_IFACE_STATS = "/proc/net/xt_qtaguid/iface_stat_fmt";
-
-enum Tx_Rx {
-    TX,
-    RX
-};
-
-enum Tcp_Udp {
-    TCP,
-    UDP,
-    TCP_AND_UDP
-};
+static const char* QTAGUID_UID_STATS = "/proc/net/xt_qtaguid/stats";
 
 // NOTE: keep these in sync with TrafficStats.java
 static const uint64_t UNKNOWN = -1;
@@ -84,27 +74,6 @@ static uint64_t getStatsType(struct Stats* stats, StatsType type) {
     }
 }
 
-// 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) ALOGE("Can't open %s: %s", filename, strerror(errno));
-        return -1;
-    }
-
-    int len = read(fd, buf, sizeof(buf) - 1);
-    if (len < 0) {
-        ALOGE("Can't read %s: %s", filename, strerror(errno));
-        close(fd);
-        return -1;
-    }
-
-    close(fd);
-    buf[len] = '\0';
-    return atoll(buf);
-}
-
 static int parseIfaceStats(const char* iface, struct Stats* stats) {
     FILE *fp = fopen(QTAGUID_IFACE_STATS, "r");
     if (fp == NULL) {
@@ -149,6 +118,36 @@ static int parseIfaceStats(const char* iface, struct Stats* stats) {
     return 0;
 }
 
+static int parseUidStats(const uint32_t uid, struct Stats* stats) {
+    FILE *fp = fopen(QTAGUID_UID_STATS, "r");
+    if (fp == NULL) {
+        return -1;
+    }
+
+    char buffer[256];
+    char iface[32];
+    uint32_t idx, cur_uid, set;
+    uint64_t tag, rxBytes, rxPackets, txBytes, txPackets;
+
+    while (fgets(buffer, 256, fp) != NULL) {
+        if (sscanf(buffer, "%d %31s 0x%llx %u %u %llu %llu %llu %llu", &idx,
+                iface, &tag, &cur_uid, &set, &rxBytes, &rxPackets, &txBytes,
+                &txPackets) == 9) {
+            if (uid == cur_uid && tag == 0L) {
+                stats->rxBytes += rxBytes;
+                stats->rxPackets += rxPackets;
+                stats->txBytes += txBytes;
+                stats->txPackets += txPackets;
+            }
+        }
+    }
+
+    if (fclose(fp) != 0) {
+        return -1;
+    }
+    return 0;
+}
+
 static jlong getTotalStat(JNIEnv* env, jclass clazz, jint type) {
     struct Stats stats;
     memset(&stats, 0, sizeof(Stats));
@@ -174,160 +173,20 @@ static jlong getIfaceStat(JNIEnv* env, jclass clazz, jstring iface, jint type) {
     }
 }
 
-
-// Per-UID stats require reading from a constructed filename.
-
-static jlong getUidBytes(JNIEnv* env, jobject clazz, jint uid,
-                         enum Tx_Rx tx_or_rx, enum Tcp_Udp tcp_or_udp) {
-    char tcp_filename[80], udp_filename[80];
-    jlong tcp_bytes = -1, udp_bytes = -1, total_bytes = -1;
-
-    switch (tx_or_rx) {
-        case TX:
-            sprintf(tcp_filename, "/proc/uid_stat/%d/tcp_snd", uid);
-            sprintf(udp_filename, "/proc/uid_stat/%d/udp_snd", uid);
-            break;
-        case RX:
-            sprintf(tcp_filename, "/proc/uid_stat/%d/tcp_rcv", uid);
-            sprintf(udp_filename, "/proc/uid_stat/%d/udp_rcv", uid);
-            break;
-        default:
-            return -1;
-    }
-
-    switch (tcp_or_udp) {
-        case TCP:
-            tcp_bytes = readNumber(tcp_filename);
-            total_bytes = (tcp_bytes >= 0) ? tcp_bytes : -1;
-            break;
-        case UDP:
-            udp_bytes = readNumber(udp_filename);
-            total_bytes = (udp_bytes >= 0) ? udp_bytes : -1;
-            break;
-        case TCP_AND_UDP:
-            tcp_bytes = readNumber(tcp_filename);
-            total_bytes += (tcp_bytes >= 0 ? tcp_bytes : 0);
-
-            udp_bytes = readNumber(udp_filename);
-            total_bytes += (udp_bytes >= 0 ? udp_bytes : 0);
-            break;
-        default:
-            return -1;
-    }
-
-    return total_bytes;
-}
-
-static jlong getUidPkts(JNIEnv* env, jobject clazz, jint uid,
-                         enum Tx_Rx tx_or_rx, enum Tcp_Udp tcp_or_udp) {
-    char tcp_filename[80], udp_filename[80];
-    jlong tcp_pkts = -1, udp_pkts = -1, total_pkts = -1;
-
-    switch (tx_or_rx) {
-        case TX:
-            sprintf(tcp_filename, "/proc/uid_stat/%d/tcp_snd_pkt", uid);
-            sprintf(udp_filename, "/proc/uid_stat/%d/udp_snd_pkt", uid);
-            break;
-        case RX:
-            sprintf(tcp_filename, "/proc/uid_stat/%d/tcp_rcv_pkt", uid);
-            sprintf(udp_filename, "/proc/uid_stat/%d/udp_rcv_pkt", uid);
-            break;
-        default:
-            return -1;
-    }
-
-    switch (tcp_or_udp) {
-        case TCP:
-            tcp_pkts = readNumber(tcp_filename);
-            total_pkts = (tcp_pkts >= 0) ? tcp_pkts : -1;
-            break;
-        case UDP:
-            udp_pkts = readNumber(udp_filename);
-            total_pkts = (udp_pkts >= 0) ? udp_pkts : -1;
-            break;
-        case TCP_AND_UDP:
-            tcp_pkts = readNumber(tcp_filename);
-            total_pkts += (tcp_pkts >= 0 ? tcp_pkts : 0);
-
-            udp_pkts = readNumber(udp_filename);
-            total_pkts += (udp_pkts >= 0 ? udp_pkts : 0);
-            break;
-        default:
-            return -1;
+static jlong getUidStat(JNIEnv* env, jclass clazz, jint uid, jint type) {
+    struct Stats stats;
+    memset(&stats, 0, sizeof(Stats));
+    if (parseUidStats(uid, &stats) == 0) {
+        return getStatsType(&stats, (StatsType) type);
+    } else {
+        return UNKNOWN;
     }
-
-    return total_pkts;
-}
-
-static jlong getUidRxBytes(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidBytes(env, clazz, uid, RX, TCP_AND_UDP);
-}
-
-static jlong getUidTxBytes(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidBytes(env, clazz, uid, TX, TCP_AND_UDP);
-}
-
-/* TCP Segments + UDP Packets */
-static jlong getUidTxPackets(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidPkts(env, clazz, uid, TX, TCP_AND_UDP);
-}
-
-/* TCP Segments + UDP Packets */
-static jlong getUidRxPackets(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidPkts(env, clazz, uid, RX, TCP_AND_UDP);
-}
-
-static jlong getUidTcpTxBytes(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidBytes(env, clazz, uid, TX, TCP);
-}
-
-static jlong getUidTcpRxBytes(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidBytes(env, clazz, uid, RX, TCP);
-}
-
-static jlong getUidUdpTxBytes(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidBytes(env, clazz, uid, TX, UDP);
-}
-
-static jlong getUidUdpRxBytes(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidBytes(env, clazz, uid, RX, UDP);
-}
-
-static jlong getUidTcpTxSegments(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidPkts(env, clazz, uid, TX, TCP);
-}
-
-static jlong getUidTcpRxSegments(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidPkts(env, clazz, uid, RX, TCP);
-}
-
-static jlong getUidUdpTxPackets(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidPkts(env, clazz, uid, TX, UDP);
-}
-
-static jlong getUidUdpRxPackets(JNIEnv* env, jobject clazz, jint uid) {
-    return getUidPkts(env, clazz, uid, RX, UDP);
 }
 
 static JNINativeMethod gMethods[] = {
     {"nativeGetTotalStat", "(I)J", (void*) getTotalStat},
     {"nativeGetIfaceStat", "(Ljava/lang/String;I)J", (void*) getIfaceStat},
-
-    /* Per-UID Stats */
-    {"getUidTxBytes", "(I)J", (void*) getUidTxBytes},
-    {"getUidRxBytes", "(I)J", (void*) getUidRxBytes},
-    {"getUidTxPackets", "(I)J", (void*) getUidTxPackets},
-    {"getUidRxPackets", "(I)J", (void*) getUidRxPackets},
-
-    {"getUidTcpTxBytes", "(I)J", (void*) getUidTcpTxBytes},
-    {"getUidTcpRxBytes", "(I)J", (void*) getUidTcpRxBytes},
-    {"getUidUdpTxBytes", "(I)J", (void*) getUidUdpTxBytes},
-    {"getUidUdpRxBytes", "(I)J", (void*) getUidUdpRxBytes},
-
-    {"getUidTcpTxSegments", "(I)J", (void*) getUidTcpTxSegments},
-    {"getUidTcpRxSegments", "(I)J", (void*) getUidTcpRxSegments},
-    {"getUidUdpTxPackets", "(I)J", (void*) getUidUdpTxPackets},
-    {"getUidUdpRxPackets", "(I)J", (void*) getUidUdpRxPackets},
+    {"nativeGetUidStat", "(II)J", (void*) getUidStat},
 };
 
 int register_android_net_TrafficStats(JNIEnv* env) {