Remove the gettetherstats command.

Bug: 32163131
Bug: 64995262
Test: netd_{unit,integration}_test pass
Test: tethering data usage UI reflects actual data usage
Change-Id: I1722f64cf775e73d71df997f6bae4820133e67bf
diff --git a/server/CommandListener.cpp b/server/CommandListener.cpp
index 10f069e..1382160 100644
--- a/server/CommandListener.cpp
+++ b/server/CommandListener.cpp
@@ -971,25 +971,6 @@
         return 0;
 
     }
-    if (!strcmp(argv[1], "gettetherstats")) {
-        std::string extraProcessingInfo = "";
-        if (argc != 2) {
-            sendGenericSyntaxError(cli, "gettetherstats");
-            return 0;
-        }
-        if (gCtls->tetherCtrl.ifacePairList.empty()) {
-            cli->sendMsg(ResponseCode::CommandOkay, "Tethering stats list completed", false);
-            return 0;
-        }
-        int rc = gCtls->tetherCtrl.getTetherStats(cli, extraProcessingInfo);
-        if (rc) {
-                extraProcessingInfo.insert(0, "Failed to get tethering stats.\n");
-                sendGenericOpFailed(cli, extraProcessingInfo.c_str());
-                return 0;
-        }
-        return 0;
-
-    }
 
     cli->sendMsg(ResponseCode::CommandSyntaxError, "Unknown bandwidth cmd", false);
     return 0;
diff --git a/server/NetdNativeService.cpp b/server/NetdNativeService.cpp
index 3f10d7c..ec4360a 100644
--- a/server/NetdNativeService.cpp
+++ b/server/NetdNativeService.cpp
@@ -323,8 +323,7 @@
 binder::Status NetdNativeService::tetherGetStats(PersistableBundle *bundle) {
     NETD_LOCKING_RPC(NETWORK_STACK, gCtls->tetherCtrl.lock)
 
-    std::string extraProcessingInfo;
-    const auto& statsList = gCtls->tetherCtrl.getTetherStats(extraProcessingInfo);
+    const auto& statsList = gCtls->tetherCtrl.getTetherStats();
     if (!isOk(statsList)) {
         return toBinderStatus(statsList);
     }
diff --git a/server/TetherController.cpp b/server/TetherController.cpp
index 334da2e..3f6efe9 100644
--- a/server/TetherController.cpp
+++ b/server/TetherController.cpp
@@ -714,16 +714,9 @@
     return 0;
 }
 
-std::string TetherController::TetherStats::getStatsLine() const {
-    std::string msg;
-    StringAppendF(&msg, "%s %s %" PRId64" %" PRId64" %" PRId64" %" PRId64, intIface.c_str(),
-                  extIface.c_str(), rxBytes, rxPackets, txBytes, txPackets);
-    return msg;
-}
-
-StatusOr<TetherController::TetherStatsList> TetherController::getTetherStats(
-        std::string& extraProcessingInfo) {
+StatusOr<TetherController::TetherStatsList> TetherController::getTetherStats() {
     TetherStatsList statsList;
+    std::string parsedIptablesOutput;
 
     for (const IptablesTarget target : {V4, V6}) {
         std::string statsString;
@@ -732,30 +725,15 @@
                                                       target, ret));
         }
 
-        if (int ret = addForwardChainStats(statsList, statsString, extraProcessingInfo)) {
+        if (int ret = addForwardChainStats(statsList, statsString, parsedIptablesOutput)) {
             return statusFromErrno(-ret, StringPrintf("failed to parse %s tether stats:\n%s",
                                                       target == V4 ? "IPv4": "IPv6",
-                                                      extraProcessingInfo.c_str()));
+                                                      parsedIptablesOutput.c_str()));
         }
     }
 
     return statsList;
 }
 
-int TetherController::getTetherStats(SocketClient *cli, std::string &extraProcessingInfo) {
-    StatusOr<TetherStatsList> statsList = getTetherStats(extraProcessingInfo);
-    if (!isOk(statsList)) {
-        return -1;
-    }
-
-    for (const auto& stats: statsList.value()) {
-        cli->sendMsg(ResponseCode::TetheringStatsListResult,
-                     stats.getStatsLine().c_str(), false);
-    }
-    cli->sendMsg(ResponseCode::CommandOkay, "Tethering stats list completed", false);
-
-    return 0;
-}
-
 }  // namespace net
 }  // namespace android
diff --git a/server/TetherController.h b/server/TetherController.h
index e715a41..df43a7b 100644
--- a/server/TetherController.h
+++ b/server/TetherController.h
@@ -88,11 +88,6 @@
         int64_t rxPackets = -1;
         int64_t txBytes = -1;
         int64_t txPackets = -1;
-        /*
-         * Returns a new string representing this:
-         * intIface extIface rx_bytes rx_packets tx_bytes tx_packets
-         */
-        std::string getStatsLine() const;
 
         bool addStatsIfMatch(const TetherStats& other) {
             if (intIface == other.intIface && extIface == other.extIface) {
@@ -108,13 +103,7 @@
 
     typedef std::vector<TetherStats> TetherStatsList;
 
-    StatusOr<TetherStatsList> getTetherStats(std::string &extraProcessingInfo);
-
-    /*
-     * Sends out to the cli a list of stats TetheringStatsListResult+CommandOkay).
-     * Error is to be handled on the outside.
-     */
-    int getTetherStats(SocketClient *cli, std::string &extraProcessingInfo);
+    StatusOr<TetherStatsList> getTetherStats();
 
     /*
      * extraProcessingInfo: contains raw parsed data, and error info.
diff --git a/server/TetherControllerTest.cpp b/server/TetherControllerTest.cpp
index c13758c..5043d12 100644
--- a/server/TetherControllerTest.cpp
+++ b/server/TetherControllerTest.cpp
@@ -28,12 +28,16 @@
 
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
+#include <netdutils/StatusOr.h>
 
 #include "TetherController.h"
 #include "IptablesBaseTest.h"
 
 using android::base::Join;
 using android::base::StringPrintf;
+using android::netdutils::StatusOr;
+using TetherStats = android::net::TetherController::TetherStats;
+using TetherStatsList = android::net::TetherController::TetherStatsList;
 
 namespace android {
 namespace net {
@@ -219,62 +223,45 @@
     "   20000 20000000 RETURN     all      rmnet0 wlan0   ::/0                 ::/0",
 }, '\n');
 
-std::string readSocketClientResponse(int fd) {
-    char buf[32768];
-    ssize_t bytesRead = read(fd, buf, sizeof(buf));
-    if (bytesRead < 0) {
-        return "";
-    }
-    for (int i = 0; i < bytesRead; i++) {
-        if (buf[i] == '\0') buf[i] = '\n';
-    }
-    return std::string(buf, bytesRead);
-}
-
-void expectNoSocketClientResponse(int fd) {
-    char buf[64];
-    EXPECT_EQ(-1, read(fd, buf, sizeof(buf))) << "Unexpected response: " << buf << "\n";
+void expectTetherStatsEqual(const TetherController::TetherStats& expected,
+                            const TetherController::TetherStats& actual) {
+    EXPECT_EQ(expected.intIface, actual.intIface);
+    EXPECT_EQ(expected.extIface, actual.extIface);
+    EXPECT_EQ(expected.rxBytes, actual.rxBytes);
+    EXPECT_EQ(expected.txBytes, actual.txBytes);
+    EXPECT_EQ(expected.rxPackets, actual.rxPackets);
+    EXPECT_EQ(expected.txPackets, actual.txPackets);
 }
 
 TEST_F(TetherControllerTest, TestGetTetherStats) {
-    int socketPair[2];
-    ASSERT_EQ(0, socketpair(AF_UNIX, SOCK_STREAM, 0, socketPair));
-    ASSERT_EQ(0, fcntl(socketPair[0], F_SETFL, O_NONBLOCK | fcntl(socketPair[0], F_GETFL)));
-    ASSERT_EQ(0, fcntl(socketPair[1], F_SETFL, O_NONBLOCK | fcntl(socketPair[1], F_GETFL)));
-    SocketClient cli(socketPair[0], false);
-
-    std::string err;
-
     // If no filter is specified, both IPv4 and IPv6 counters must have at least one interface pair.
     addIptablesRestoreOutput(kIPv4TetherCounters);
-    ASSERT_EQ(-1, mTetherCtrl.getTetherStats(&cli, err));
-    expectNoSocketClientResponse(socketPair[1]);
+    ASSERT_FALSE(isOk(mTetherCtrl.getTetherStats()));
     clearIptablesRestoreOutput();
 
     addIptablesRestoreOutput(kIPv6TetherCounters);
-    ASSERT_EQ(-1, mTetherCtrl.getTetherStats(&cli, err));
+    ASSERT_FALSE(isOk(mTetherCtrl.getTetherStats()));
     clearIptablesRestoreOutput();
 
     // IPv4 and IPv6 counters are properly added together.
     addIptablesRestoreOutput(kIPv4TetherCounters, kIPv6TetherCounters);
-    std::string expected =
-            "114 wlan0 rmnet0 10002373 10026 20002002 20027\n"
-            "114 bt-pan rmnet0 107471 1040 1708806 1450\n"
-            "200 Tethering stats list completed\n";
-    ASSERT_EQ(0, mTetherCtrl.getTetherStats(&cli, err));
-    ASSERT_EQ(expected, readSocketClientResponse(socketPair[1]));
-    expectNoSocketClientResponse(socketPair[1]);
+    TetherStats expected0("wlan0", "rmnet0", 10002373, 10026, 20002002, 20027);
+    TetherStats expected1("bt-pan", "rmnet0", 107471, 1040, 1708806, 1450);
+    StatusOr<TetherStatsList> result = mTetherCtrl.getTetherStats();
+    ASSERT_TRUE(isOk(result));
+    TetherStatsList actual = result.value();
+    ASSERT_EQ(2U, actual.size());
+    expectTetherStatsEqual(expected0, result.value()[0]);
+    expectTetherStatsEqual(expected1, result.value()[1]);
     clearIptablesRestoreOutput();
 
     // No stats: error.
     addIptablesRestoreOutput("", kIPv6TetherCounters);
-    ASSERT_EQ(-1, mTetherCtrl.getTetherStats(&cli, err));
-    expectNoSocketClientResponse(socketPair[1]);
+    ASSERT_FALSE(isOk(mTetherCtrl.getTetherStats()));
     clearIptablesRestoreOutput();
 
     addIptablesRestoreOutput(kIPv4TetherCounters, "");
-    ASSERT_EQ(-1, mTetherCtrl.getTetherStats(&cli, err));
-    expectNoSocketClientResponse(socketPair[1]);
+    ASSERT_FALSE(isOk(mTetherCtrl.getTetherStats()));
     clearIptablesRestoreOutput();
 
     // Include only one pair of interfaces and things are fine.
@@ -283,24 +270,26 @@
     counterLines.resize(4);
     std::string counters = Join(counterLines, "\n") + "\n";
     addIptablesRestoreOutput(counters, counters);
-    expected =
-            "114 wlan0 rmnet0 4746 52 4004 54\n"
-            "200 Tethering stats list completed\n";
-    ASSERT_EQ(0, mTetherCtrl.getTetherStats(&cli, err));
-    ASSERT_EQ(expected, readSocketClientResponse(socketPair[1]));
+    TetherStats expected1_0("wlan0", "rmnet0", 4746, 52, 4004, 54);
+    result = mTetherCtrl.getTetherStats();
+    ASSERT_TRUE(isOk(result));
+    actual = result.value();
+    ASSERT_EQ(1U, actual.size());
+    expectTetherStatsEqual(expected1_0, actual[0]);
     clearIptablesRestoreOutput();
 
     // But if interfaces aren't paired, it's always an error.
     counterLines.resize(3);
     counters = Join(counterLines, "\n") + "\n";
     addIptablesRestoreOutput(counters, counters);
-    ASSERT_EQ(-1, mTetherCtrl.getTetherStats(&cli, err));
-    expectNoSocketClientResponse(socketPair[1]);
+    result = mTetherCtrl.getTetherStats();
+    ASSERT_FALSE(isOk(result));
     clearIptablesRestoreOutput();
 
     // Token unit test of the fact that we return the stats in the error message which the caller
     // ignores.
     std::string expectedError = counters;
+    std::string err = result.status().msg();
     ASSERT_LE(expectedError.size(), err.size());
     EXPECT_TRUE(std::equal(expectedError.rbegin(), expectedError.rend(), err.rbegin()));
 }