Test to measure UDP roundtrip time between two devices on the same network.

Change-Id: I4c9a5190efe18da8b6be7d68bda91df878c4118c

6 files changed, 1822 insertions, 0 deletions

diff --git a/media/libstagefright/wifi-display/ANetworkSession.cpp b/media/libstagefright/wifi-display/ANetworkSession.cpp
new file mode 100644
index 0000000..ee0600c
--- /dev/null
+++ b/media/libstagefright/wifi-display/ANetworkSession.cpp
@@ -0,0 +1,994 @@
+/*
+ * Copyright 2012, 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_NDEBUG 0
+#define LOG_TAG "NetworkSession"
+#include <utils/Log.h>
+
+#include "ANetworkSession.h"
+#include "ParsedMessage.h"
+
+#include <arpa/inet.h>
+#include <fcntl.h>
+#include <net/if.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <sys/socket.h>
+
+#include <media/stagefright/foundation/ABuffer.h>
+#include <media/stagefright/foundation/ADebug.h>
+#include <media/stagefright/foundation/AMessage.h>
+#include <media/stagefright/foundation/hexdump.h>
+#include <media/stagefright/Utils.h>
+
+namespace android {
+
+static const size_t kMaxUDPSize = 1500;
+
+struct ANetworkSession::NetworkThread : public Thread {
+    NetworkThread(ANetworkSession *session);
+
+protected:
+    virtual ~NetworkThread();
+
+private:
+    ANetworkSession *mSession;
+
+    virtual bool threadLoop();
+
+    DISALLOW_EVIL_CONSTRUCTORS(NetworkThread);
+};
+
+struct ANetworkSession::Session : public RefBase {
+    enum State {
+        CONNECTING,
+        CONNECTED,
+        LISTENING,
+        DATAGRAM,
+    };
+
+    Session(int32_t sessionID,
+            State state,
+            int s,
+            const sp<AMessage> &notify);
+
+    int32_t sessionID() const;
+    int socket() const;
+    sp<AMessage> getNotificationMessage() const;
+
+    bool isListening() const;
+
+    bool wantsToRead();
+    bool wantsToWrite();
+
+    status_t readMore();
+    status_t writeMore();
+
+    status_t sendRequest(const void *data, ssize_t size);
+
+protected:
+    virtual ~Session();
+
+private:
+    int32_t mSessionID;
+    State mState;
+    int mSocket;
+    sp<AMessage> mNotify;
+    bool mSawReceiveFailure, mSawSendFailure;
+
+    AString mOutBuffer;
+    List<size_t> mOutBufferSizes;
+
+    AString mInBuffer;
+
+    void notifyError(bool send, status_t err, const char *detail);
+    void notify(NotificationReason reason);
+
+    DISALLOW_EVIL_CONSTRUCTORS(Session);
+};
+////////////////////////////////////////////////////////////////////////////////
+
+ANetworkSession::NetworkThread::NetworkThread(ANetworkSession *session)
+    : mSession(session) {
+}
+
+ANetworkSession::NetworkThread::~NetworkThread() {
+}
+
+bool ANetworkSession::NetworkThread::threadLoop() {
+    mSession->threadLoop();
+
+    return true;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+ANetworkSession::Session::Session(
+        int32_t sessionID,
+        State state,
+        int s,
+        const sp<AMessage> &notify)
+    : mSessionID(sessionID),
+      mState(state),
+      mSocket(s),
+      mNotify(notify),
+      mSawReceiveFailure(false),
+      mSawSendFailure(false) {
+    if (mState == CONNECTED) {
+        struct sockaddr_in localAddr;
+        socklen_t localAddrLen = sizeof(localAddr);
+
+        int res = getsockname(
+                mSocket, (struct sockaddr *)&localAddr, &localAddrLen);
+        CHECK_GE(res, 0);
+
+        struct sockaddr_in remoteAddr;
+        socklen_t remoteAddrLen = sizeof(remoteAddr);
+
+        res = getpeername(
+                mSocket, (struct sockaddr *)&remoteAddr, &remoteAddrLen);
+        CHECK_GE(res, 0);
+
+        in_addr_t addr = ntohl(localAddr.sin_addr.s_addr);
+        AString localAddrString = StringPrintf(
+                "%d.%d.%d.%d",
+                (addr >> 24),
+                (addr >> 16) & 0xff,
+                (addr >> 8) & 0xff,
+                addr & 0xff);
+
+        addr = ntohl(remoteAddr.sin_addr.s_addr);
+        AString remoteAddrString = StringPrintf(
+                "%d.%d.%d.%d",
+                (addr >> 24),
+                (addr >> 16) & 0xff,
+                (addr >> 8) & 0xff,
+                addr & 0xff);
+
+        sp<AMessage> msg = mNotify->dup();
+        msg->setInt32("sessionID", mSessionID);
+        msg->setInt32("reason", kWhatClientConnected);
+        msg->setString("server-ip", localAddrString.c_str());
+        msg->setInt32("server-port", ntohs(localAddr.sin_port));
+        msg->setString("client-ip", remoteAddrString.c_str());
+        msg->setInt32("client-port", ntohs(remoteAddr.sin_port));
+        msg->post();
+    }
+}
+
+ANetworkSession::Session::~Session() {
+    ALOGI("Session %d gone", mSessionID);
+
+    close(mSocket);
+    mSocket = -1;
+}
+
+int32_t ANetworkSession::Session::sessionID() const {
+    return mSessionID;
+}
+
+int ANetworkSession::Session::socket() const {
+    return mSocket;
+}
+
+sp<AMessage> ANetworkSession::Session::getNotificationMessage() const {
+    return mNotify;
+}
+
+bool ANetworkSession::Session::isListening() const {
+    return mState == LISTENING;
+}
+
+bool ANetworkSession::Session::wantsToRead() {
+    return !mSawReceiveFailure && mState != CONNECTING;
+}
+
+bool ANetworkSession::Session::wantsToWrite() {
+    return !mSawSendFailure
+        && (mState == CONNECTING
+            || ((mState == CONNECTED || mState == DATAGRAM)
+                    && !mOutBuffer.empty()));
+}
+
+status_t ANetworkSession::Session::readMore() {
+    if (mState == DATAGRAM) {
+        status_t err;
+        do {
+            sp<ABuffer> buf = new ABuffer(kMaxUDPSize);
+
+            struct sockaddr_in remoteAddr;
+            socklen_t remoteAddrLen = sizeof(remoteAddr);
+
+            ssize_t n;
+            do {
+                n = recvfrom(
+                        mSocket, buf->data(), buf->capacity(), 0,
+                        (struct sockaddr *)&remoteAddr, &remoteAddrLen);
+            } while (n < 0 && errno == EINTR);
+
+            err = OK;
+            if (n < 0) {
+                err = -errno;
+            } else if (n == 0) {
+                err = -ECONNRESET;
+            } else {
+                buf->setRange(0, n);
+
+                int64_t nowUs = ALooper::GetNowUs();
+                buf->meta()->setInt64("arrivalTimeUs", nowUs);
+
+                sp<AMessage> notify = mNotify->dup();
+                notify->setInt32("sessionID", mSessionID);
+                notify->setInt32("reason", kWhatDatagram);
+
+                uint32_t ip = ntohl(remoteAddr.sin_addr.s_addr);
+                notify->setString(
+                        "fromAddr",
+                        StringPrintf(
+                            "%u.%u.%u.%u",
+                            ip >> 24,
+                            (ip >> 16) & 0xff,
+                            (ip >> 8) & 0xff,
+                            ip & 0xff).c_str());
+
+                notify->setInt32("fromPort", ntohs(remoteAddr.sin_port));
+
+                notify->setBuffer("data", buf);
+                notify->post();
+            }
+        } while (err == OK);
+
+        if (err == -EAGAIN) {
+            err = OK;
+        }
+
+        if (err != OK) {
+            notifyError(false /* send */, err, "Recvfrom failed.");
+            mSawReceiveFailure = true;
+        }
+
+        return err;
+    }
+
+    char tmp[512];
+    ssize_t n;
+    do {
+        n = recv(mSocket, tmp, sizeof(tmp), 0);
+    } while (n < 0 && errno == EINTR);
+
+    status_t err = OK;
+
+    if (n > 0) {
+        mInBuffer.append(tmp, n);
+
+#if 0
+        ALOGI("in:");
+        hexdump(tmp, n);
+#endif
+    } else if (n < 0) {
+        err = -errno;
+    } else {
+        err = -ECONNRESET;
+    }
+
+    for (;;) {
+        size_t length;
+
+        if (mInBuffer.size() > 0 && mInBuffer.c_str()[0] == '$') {
+            if (mInBuffer.size() < 4) {
+                break;
+            }
+
+            length = U16_AT((const uint8_t *)mInBuffer.c_str() + 2);
+
+            if (mInBuffer.size() < 4 + length) {
+                break;
+            }
+
+            sp<AMessage> notify = mNotify->dup();
+            notify->setInt32("sessionID", mSessionID);
+            notify->setInt32("reason", kWhatBinaryData);
+            notify->setInt32("channel", mInBuffer.c_str()[1]);
+
+            sp<ABuffer> data = new ABuffer(length);
+            memcpy(data->data(), mInBuffer.c_str() + 4, length);
+
+            int64_t nowUs = ALooper::GetNowUs();
+            data->meta()->setInt64("arrivalTimeUs", nowUs);
+
+            notify->setBuffer("data", data);
+            notify->post();
+
+            mInBuffer.erase(0, 4 + length);
+            continue;
+        }
+
+        sp<ParsedMessage> msg =
+            ParsedMessage::Parse(
+                    mInBuffer.c_str(), mInBuffer.size(), err != OK, &length);
+
+        if (msg == NULL) {
+            break;
+        }
+
+        sp<AMessage> notify = mNotify->dup();
+        notify->setInt32("sessionID", mSessionID);
+        notify->setInt32("reason", kWhatData);
+        notify->setObject("data", msg);
+        notify->post();
+
+#if 1
+        // XXX The dongle sends the wrong content length header on a
+        // SET_PARAMETER request that signals a "wfd_idr_request".
+        // (17 instead of 19).
+        const char *content = msg->getContent();
+        if (content && !memcmp(content, "wfd_idr_request\r\n", 17)) {
+            length += 2;
+        }
+#endif
+
+        mInBuffer.erase(0, length);
+
+        if (err != OK) {
+            break;
+        }
+    }
+
+    if (err != OK) {
+        notifyError(false /* send */, err, "Recv failed.");
+        mSawReceiveFailure = true;
+    }
+
+    return err;
+}
+
+status_t ANetworkSession::Session::writeMore() {
+    if (mState == DATAGRAM) {
+        CHECK(!mOutBufferSizes.empty());
+
+        status_t err;
+        do {
+            size_t size = *mOutBufferSizes.begin();
+
+            CHECK_GE(mOutBuffer.size(), size);
+
+            int n;
+            do {
+                n = send(mSocket, mOutBuffer.c_str(), size, 0);
+            } while (n < 0 && errno == EINTR);
+
+            err = OK;
+
+            if (n > 0) {
+                mOutBufferSizes.erase(mOutBufferSizes.begin());
+                mOutBuffer.erase(0, n);
+            } else if (n < 0) {
+                err = -errno;
+            } else if (n == 0) {
+                err = -ECONNRESET;
+            }
+        } while (err == OK && !mOutBufferSizes.empty());
+
+        if (err == -EAGAIN) {
+            err = OK;
+        }
+
+        if (err != OK) {
+            notifyError(true /* send */, err, "Send datagram failed.");
+            mSawSendFailure = true;
+        }
+
+        return err;
+    }
+
+    if (mState == CONNECTING) {
+        int err;
+        socklen_t optionLen = sizeof(err);
+        CHECK_EQ(getsockopt(mSocket, SOL_SOCKET, SO_ERROR, &err, &optionLen), 0);
+        CHECK_EQ(optionLen, (socklen_t)sizeof(err));
+
+        if (err != 0) {
+            notifyError(kWhatError, -err, "Connection failed");
+            mSawSendFailure = true;
+
+            return UNKNOWN_ERROR;
+        }
+
+        mState = CONNECTED;
+        notify(kWhatConnected);
+
+        return OK;
+    }
+
+    CHECK_EQ(mState, CONNECTED);
+    CHECK(!mOutBuffer.empty());
+
+    ssize_t n;
+    do {
+        n = send(mSocket, mOutBuffer.c_str(), mOutBuffer.size(), 0);
+    } while (n < 0 && errno == EINTR);
+
+    status_t err = OK;
+
+    if (n > 0) {
+        ALOGI("out:");
+        hexdump(mOutBuffer.c_str(), n);
+
+        mOutBuffer.erase(0, n);
+    } else if (n < 0) {
+        err = -errno;
+    } else if (n == 0) {
+        err = -ECONNRESET;
+    }
+
+    if (err != OK) {
+        notifyError(true /* send */, err, "Send failed.");
+        mSawSendFailure = true;
+    }
+
+    return err;
+}
+
+status_t ANetworkSession::Session::sendRequest(const void *data, ssize_t size) {
+    CHECK(mState == CONNECTED || mState == DATAGRAM);
+
+    mOutBuffer.append(
+            (const char *)data,
+            (size >= 0) ? size : strlen((const char *)data));
+
+    if (mState == DATAGRAM) {
+        CHECK_GE(size, 0);
+        mOutBufferSizes.push_back(size);
+    }
+
+    return OK;
+}
+
+void ANetworkSession::Session::notifyError(
+        bool send, status_t err, const char *detail) {
+    sp<AMessage> msg = mNotify->dup();
+    msg->setInt32("sessionID", mSessionID);
+    msg->setInt32("reason", kWhatError);
+    msg->setInt32("send", send);
+    msg->setInt32("err", err);
+    msg->setString("detail", detail);
+    msg->post();
+}
+
+void ANetworkSession::Session::notify(NotificationReason reason) {
+    sp<AMessage> msg = mNotify->dup();
+    msg->setInt32("sessionID", mSessionID);
+    msg->setInt32("reason", reason);
+    msg->post();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+ANetworkSession::ANetworkSession()
+    : mNextSessionID(1) {
+    mPipeFd[0] = mPipeFd[1] = -1;
+}
+
+ANetworkSession::~ANetworkSession() {
+    stop();
+}
+
+status_t ANetworkSession::start() {
+    if (mThread != NULL) {
+        return INVALID_OPERATION;
+    }
+
+    int res = pipe(mPipeFd);
+    if (res != 0) {
+        mPipeFd[0] = mPipeFd[1] = -1;
+        return -errno;
+    }
+
+    mThread = new NetworkThread(this);
+
+    status_t err = mThread->run("ANetworkSession", ANDROID_PRIORITY_AUDIO);
+
+    if (err != OK) {
+        mThread.clear();
+
+        close(mPipeFd[0]);
+        close(mPipeFd[1]);
+        mPipeFd[0] = mPipeFd[1] = -1;
+
+        return err;
+    }
+
+    return OK;
+}
+
+status_t ANetworkSession::stop() {
+    if (mThread == NULL) {
+        return INVALID_OPERATION;
+    }
+
+    mThread->requestExit();
+    interrupt();
+    mThread->requestExitAndWait();
+
+    mThread.clear();
+
+    close(mPipeFd[0]);
+    close(mPipeFd[1]);
+    mPipeFd[0] = mPipeFd[1] = -1;
+
+    return OK;
+}
+
+status_t ANetworkSession::createRTSPClient(
+        const char *host, unsigned port, const sp<AMessage> &notify,
+        int32_t *sessionID) {
+    return createClientOrServer(
+            kModeCreateRTSPClient,
+            0 /* port */,
+            host,
+            port,
+            notify,
+            sessionID);
+}
+
+status_t ANetworkSession::createRTSPServer(
+        unsigned port, const sp<AMessage> &notify, int32_t *sessionID) {
+    return createClientOrServer(
+            kModeCreateRTSPServer,
+            port,
+            NULL /* remoteHost */,
+            0 /* remotePort */,
+            notify,
+            sessionID);
+}
+
+status_t ANetworkSession::createUDPSession(
+        unsigned localPort, const sp<AMessage> &notify, int32_t *sessionID) {
+    return createUDPSession(localPort, NULL, 0, notify, sessionID);
+}
+
+status_t ANetworkSession::createUDPSession(
+        unsigned localPort,
+        const char *remoteHost,
+        unsigned remotePort,
+        const sp<AMessage> &notify,
+        int32_t *sessionID) {
+    return createClientOrServer(
+            kModeCreateUDPSession,
+            localPort,
+            remoteHost,
+            remotePort,
+            notify,
+            sessionID);
+}
+
+status_t ANetworkSession::destroySession(int32_t sessionID) {
+    Mutex::Autolock autoLock(mLock);
+
+    ssize_t index = mSessions.indexOfKey(sessionID);
+
+    if (index < 0) {
+        return -ENOENT;
+    }
+
+    mSessions.removeItemsAt(index);
+
+    interrupt();
+
+    return OK;
+}
+
+// static
+status_t ANetworkSession::MakeSocketNonBlocking(int s) {
+    int flags = fcntl(s, F_GETFL, 0);
+    if (flags < 0) {
+        flags = 0;
+    }
+
+    int res = fcntl(s, F_SETFL, flags | O_NONBLOCK);
+    if (res < 0) {
+        return -errno;
+    }
+
+    return OK;
+}
+
+status_t ANetworkSession::createClientOrServer(
+        Mode mode,
+        unsigned port,
+        const char *remoteHost,
+        unsigned remotePort,
+        const sp<AMessage> &notify,
+        int32_t *sessionID) {
+    Mutex::Autolock autoLock(mLock);
+
+    *sessionID = 0;
+    status_t err = OK;
+    int s, res;
+    sp<Session> session;
+
+    s = socket(
+            AF_INET,
+            (mode == kModeCreateUDPSession) ? SOCK_DGRAM : SOCK_STREAM,
+            0);
+
+    if (s < 0) {
+        err = -errno;
+        goto bail;
+    }
+
+    if (mode == kModeCreateRTSPServer) {
+        const int yes = 1;
+        res = setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes));
+
+        if (res < 0) {
+            err = -errno;
+            goto bail2;
+        }
+    }
+
+    if (mode == kModeCreateUDPSession) {
+        int size = 256 * 1024;
+
+        res = setsockopt(s, SOL_SOCKET, SO_RCVBUF, &size, sizeof(size));
+
+        if (res < 0) {
+            err = -errno;
+            goto bail2;
+        }
+
+        res = setsockopt(s, SOL_SOCKET, SO_SNDBUF, &size, sizeof(size));
+
+        if (res < 0) {
+            err = -errno;
+            goto bail2;
+        }
+    }
+
+    err = MakeSocketNonBlocking(s);
+
+    if (err != OK) {
+        goto bail2;
+    }
+
+    struct sockaddr_in addr;
+    memset(addr.sin_zero, 0, sizeof(addr.sin_zero));
+    addr.sin_family = AF_INET;
+
+    if (mode == kModeCreateRTSPClient) {
+        struct hostent *ent= gethostbyname(remoteHost);
+        if (ent == NULL) {
+            err = -h_errno;
+            goto bail2;
+        }
+
+        addr.sin_addr.s_addr = *(in_addr_t *)ent->h_addr;
+        addr.sin_port = htons(remotePort);
+    } else {
+        addr.sin_addr.s_addr = INADDR_ANY;
+        addr.sin_port = htons(port);
+    }
+
+    if (mode == kModeCreateRTSPClient) {
+        res = connect(s, (const struct sockaddr *)&addr, sizeof(addr));
+
+        CHECK_LT(res, 0);
+        if (errno == EINPROGRESS) {
+            res = 0;
+        }
+    } else {
+        res = bind(s, (const struct sockaddr *)&addr, sizeof(addr));
+
+        if (res == 0) {
+            if (mode == kModeCreateRTSPServer) {
+                res = listen(s, 4);
+            } else {
+                CHECK_EQ(mode, kModeCreateUDPSession);
+
+                if (remoteHost != NULL) {
+                    struct sockaddr_in remoteAddr;
+                    memset(remoteAddr.sin_zero, 0, sizeof(remoteAddr.sin_zero));
+                    remoteAddr.sin_family = AF_INET;
+                    remoteAddr.sin_port = htons(remotePort);
+
+                    struct hostent *ent= gethostbyname(remoteHost);
+                    if (ent == NULL) {
+                        err = -h_errno;
+                        goto bail2;
+                    }
+
+                    remoteAddr.sin_addr.s_addr = *(in_addr_t *)ent->h_addr;
+
+                    res = connect(
+                            s,
+                            (const struct sockaddr *)&remoteAddr,
+                            sizeof(remoteAddr));
+                }
+            }
+        }
+    }
+
+    if (res < 0) {
+        err = -errno;
+        goto bail2;
+    }
+
+    Session::State state;
+    switch (mode) {
+        case kModeCreateRTSPClient:
+            state = Session::CONNECTING;
+            break;
+
+        case kModeCreateRTSPServer:
+            state = Session::LISTENING;
+            break;
+
+        default:
+            CHECK_EQ(mode, kModeCreateUDPSession);
+            state = Session::DATAGRAM;
+            break;
+    }
+
+    session = new Session(
+            mNextSessionID++,
+            state,
+            s,
+            notify);
+
+    mSessions.add(session->sessionID(), session);
+
+    interrupt();
+
+    *sessionID = session->sessionID();
+
+    goto bail;
+
+bail2:
+    close(s);
+    s = -1;
+
+bail:
+    return err;
+}
+
+status_t ANetworkSession::connectUDPSession(
+        int32_t sessionID, const char *remoteHost, unsigned remotePort) {
+    Mutex::Autolock autoLock(mLock);
+
+    ssize_t index = mSessions.indexOfKey(sessionID);
+
+    if (index < 0) {
+        return -ENOENT;
+    }
+
+    const sp<Session> session = mSessions.valueAt(index);
+    int s = session->socket();
+
+    struct sockaddr_in remoteAddr;
+    memset(remoteAddr.sin_zero, 0, sizeof(remoteAddr.sin_zero));
+    remoteAddr.sin_family = AF_INET;
+    remoteAddr.sin_port = htons(remotePort);
+
+    status_t err = OK;
+    struct hostent *ent= gethostbyname(remoteHost);
+    if (ent == NULL) {
+        err = -h_errno;
+    } else {
+        remoteAddr.sin_addr.s_addr = *(in_addr_t *)ent->h_addr;
+
+        int res = connect(
+                s,
+                (const struct sockaddr *)&remoteAddr,
+                sizeof(remoteAddr));
+
+        if (res < 0) {
+            err = -errno;
+        }
+    }
+
+    return err;
+}
+
+status_t ANetworkSession::sendRequest(
+        int32_t sessionID, const void *data, ssize_t size) {
+    Mutex::Autolock autoLock(mLock);
+
+    ssize_t index = mSessions.indexOfKey(sessionID);
+
+    if (index < 0) {
+        return -ENOENT;
+    }
+
+    const sp<Session> session = mSessions.valueAt(index);
+
+    status_t err = session->sendRequest(data, size);
+
+    interrupt();
+
+    return err;
+}
+
+void ANetworkSession::interrupt() {
+    static const char dummy = 0;
+
+    ssize_t n;
+    do {
+        n = write(mPipeFd[1], &dummy, 1);
+    } while (n < 0 && errno == EINTR);
+
+    if (n < 0) {
+        ALOGW("Error writing to pipe (%s)", strerror(errno));
+    }
+}
+
+void ANetworkSession::threadLoop() {
+    fd_set rs, ws;
+    FD_ZERO(&rs);
+    FD_ZERO(&ws);
+
+    FD_SET(mPipeFd[0], &rs);
+    int maxFd = mPipeFd[0];
+
+    {
+        Mutex::Autolock autoLock(mLock);
+
+        for (size_t i = 0; i < mSessions.size(); ++i) {
+            const sp<Session> &session = mSessions.valueAt(i);
+
+            int s = session->socket();
+
+            if (s < 0) {
+                continue;
+            }
+
+            if (session->wantsToRead()) {
+                FD_SET(s, &rs);
+                if (s > maxFd) {
+                    maxFd = s;
+                }
+            }
+
+            if (session->wantsToWrite()) {
+                FD_SET(s, &ws);
+                if (s > maxFd) {
+                    maxFd = s;
+                }
+            }
+        }
+    }
+
+    int res = select(maxFd + 1, &rs, &ws, NULL, NULL /* tv */);
+
+    if (res == 0) {
+        return;
+    }
+
+    if (res < 0) {
+        if (errno == EINTR) {
+            return;
+        }
+
+        ALOGE("select failed w/ error %d (%s)", errno, strerror(errno));
+        return;
+    }
+
+    if (FD_ISSET(mPipeFd[0], &rs)) {
+        char c;
+        ssize_t n;
+        do {
+            n = read(mPipeFd[0], &c, 1);
+        } while (n < 0 && errno == EINTR);
+
+        if (n < 0) {
+            ALOGW("Error reading from pipe (%s)", strerror(errno));
+        }
+
+        --res;
+    }
+
+    {
+        Mutex::Autolock autoLock(mLock);
+
+        List<sp<Session> > sessionsToAdd;
+
+        for (size_t i = mSessions.size(); res > 0 && i-- > 0;) {
+            const sp<Session> &session = mSessions.valueAt(i);
+
+            int s = session->socket();
+
+            if (s < 0) {
+                continue;
+            }
+
+            if (FD_ISSET(s, &rs) || FD_ISSET(s, &ws)) {
+                --res;
+            }
+
+            if (FD_ISSET(s, &rs)) {
+                if (session->isListening()) {
+                    struct sockaddr_in remoteAddr;
+                    socklen_t remoteAddrLen = sizeof(remoteAddr);
+
+                    int clientSocket = accept(
+                            s, (struct sockaddr *)&remoteAddr, &remoteAddrLen);
+
+                    if (clientSocket >= 0) {
+                        status_t err = MakeSocketNonBlocking(clientSocket);
+
+                        if (err != OK) {
+                            ALOGE("Unable to make client socket non blocking, "
+                                  "failed w/ error %d (%s)",
+                                  err, strerror(-err));
+
+                            close(clientSocket);
+                            clientSocket = -1;
+                        } else {
+                            in_addr_t addr = ntohl(remoteAddr.sin_addr.s_addr);
+
+                            ALOGI("incoming connection from %d.%d.%d.%d:%d "
+                                  "(socket %d)",
+                                  (addr >> 24),
+                                  (addr >> 16) & 0xff,
+                                  (addr >> 8) & 0xff,
+                                  addr & 0xff,
+                                  ntohs(remoteAddr.sin_port),
+                                  clientSocket);
+
+                            sp<Session> clientSession =
+                                // using socket sd as sessionID
+                                new Session(
+                                        mNextSessionID++,
+                                        Session::CONNECTED,
+                                        clientSocket,
+                                        session->getNotificationMessage());
+
+                            sessionsToAdd.push_back(clientSession);
+                        }
+                    } else {
+                        ALOGE("accept returned error %d (%s)",
+                              errno, strerror(errno));
+                    }
+                } else {
+                    status_t err = session->readMore();
+                    if (err != OK) {
+                        ALOGI("readMore on socket %d failed w/ error %d (%s)",
+                              s, err, strerror(-err));
+                    }
+                }
+            }
+
+            if (FD_ISSET(s, &ws)) {
+                status_t err = session->writeMore();
+                if (err != OK) {
+                    ALOGI("writeMore on socket %d failed w/ error %d (%s)",
+                          s, err, strerror(-err));
+                }
+            }
+        }
+
+        while (!sessionsToAdd.empty()) {
+            sp<Session> session = *sessionsToAdd.begin();
+            sessionsToAdd.erase(sessionsToAdd.begin());
+
+            mSessions.add(session->sessionID(), session);
+
+            ALOGI("added clientSession %d", session->sessionID());
+        }
+    }
+}
+
+}  // namespace android
+
diff --git a/media/libstagefright/wifi-display/ANetworkSession.h b/media/libstagefright/wifi-display/ANetworkSession.h
new file mode 100644
index 0000000..0402317
--- /dev/null
+++ b/media/libstagefright/wifi-display/ANetworkSession.h
@@ -0,0 +1,109 @@
+/*
+ * Copyright 2012, 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.
+ */
+
+#ifndef A_NETWORK_SESSION_H_
+
+#define A_NETWORK_SESSION_H_
+
+#include <media/stagefright/foundation/ABase.h>
+#include <utils/KeyedVector.h>
+#include <utils/RefBase.h>
+#include <utils/Thread.h>
+
+namespace android {
+
+struct AMessage;
+
+struct ANetworkSession : public RefBase {
+    ANetworkSession();
+
+    status_t start();
+    status_t stop();
+
+    status_t createRTSPClient(
+            const char *host, unsigned port, const sp<AMessage> &notify,
+            int32_t *sessionID);
+
+    status_t createRTSPServer(
+            unsigned port, const sp<AMessage> &notify, int32_t *sessionID);
+
+    status_t createUDPSession(
+            unsigned localPort, const sp<AMessage> &notify, int32_t *sessionID);
+
+    status_t createUDPSession(
+            unsigned localPort,
+            const char *remoteHost,
+            unsigned remotePort,
+            const sp<AMessage> &notify,
+            int32_t *sessionID);
+
+    status_t connectUDPSession(
+            int32_t sessionID, const char *remoteHost, unsigned remotePort);
+
+    status_t destroySession(int32_t sessionID);
+
+    status_t sendRequest(
+            int32_t sessionID, const void *data, ssize_t size = -1);
+
+    enum NotificationReason {
+        kWhatError,
+        kWhatConnected,
+        kWhatClientConnected,
+        kWhatData,
+        kWhatDatagram,
+        kWhatBinaryData,
+    };
+
+protected:
+    virtual ~ANetworkSession();
+
+private:
+    struct NetworkThread;
+    struct Session;
+
+    Mutex mLock;
+    sp<Thread> mThread;
+
+    int32_t mNextSessionID;
+
+    int mPipeFd[2];
+
+    KeyedVector<int32_t, sp<Session> > mSessions;
+
+    enum Mode {
+        kModeCreateUDPSession,
+        kModeCreateRTSPServer,
+        kModeCreateRTSPClient,
+    };
+    status_t createClientOrServer(
+            Mode mode,
+            unsigned port,
+            const char *remoteHost,
+            unsigned remotePort,
+            const sp<AMessage> &notify,
+            int32_t *sessionID);
+
+    void threadLoop();
+    void interrupt();
+
+    static status_t MakeSocketNonBlocking(int s);
+
+    DISALLOW_EVIL_CONSTRUCTORS(ANetworkSession);
+};
+
+}  // namespace android
+
+#endif  // A_NETWORK_SESSION_H_
diff --git a/media/libstagefright/wifi-display/Android.mk b/media/libstagefright/wifi-display/Android.mk
new file mode 100644
index 0000000..114ff62
--- /dev/null
+++ b/media/libstagefright/wifi-display/Android.mk
@@ -0,0 +1,22 @@
+LOCAL_PATH:= $(call my-dir)
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES:= \
+        udptest.cpp                 \
+        ANetworkSession.cpp         \
+        ParsedMessage.cpp           \
+
+LOCAL_SHARED_LIBRARIES:= \
+        libbinder                       \
+        libgui                          \
+        libmedia                        \
+        libstagefright                  \
+        libstagefright_foundation       \
+        libutils                        \
+
+LOCAL_MODULE:= udptest
+
+LOCAL_MODULE_TAGS := debug
+
+include $(BUILD_EXECUTABLE)
diff --git a/media/libstagefright/wifi-display/ParsedMessage.cpp b/media/libstagefright/wifi-display/ParsedMessage.cpp
new file mode 100644
index 0000000..c0e60c3
--- /dev/null
+++ b/media/libstagefright/wifi-display/ParsedMessage.cpp
@@ -0,0 +1,284 @@
+/*
+ * Copyright 2012, 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.
+ */
+
+#include "ParsedMessage.h"
+
+#include <ctype.h>
+#include <media/stagefright/foundation/ABuffer.h>
+#include <media/stagefright/foundation/ADebug.h>
+
+namespace android {
+
+// static
+sp<ParsedMessage> ParsedMessage::Parse(
+        const char *data, size_t size, bool noMoreData, size_t *length) {
+    sp<ParsedMessage> msg = new ParsedMessage;
+    ssize_t res = msg->parse(data, size, noMoreData);
+
+    if (res < 0) {
+        *length = 0;
+        return NULL;
+    }
+
+    *length = res;
+    return msg;
+}
+
+ParsedMessage::ParsedMessage() {
+}
+
+ParsedMessage::~ParsedMessage() {
+}
+
+bool ParsedMessage::findString(const char *name, AString *value) const {
+    AString key = name;
+    key.tolower();
+
+    ssize_t index = mDict.indexOfKey(key);
+
+    if (index < 0) {
+        value->clear();
+
+        return false;
+    }
+
+    *value = mDict.valueAt(index);
+    return true;
+}
+
+bool ParsedMessage::findInt32(const char *name, int32_t *value) const {
+    AString stringValue;
+
+    if (!findString(name, &stringValue)) {
+        return false;
+    }
+
+    char *end;
+    *value = strtol(stringValue.c_str(), &end, 10);
+
+    if (end == stringValue.c_str() || *end != '\0') {
+        *value = 0;
+        return false;
+    }
+
+    return true;
+}
+
+const char *ParsedMessage::getContent() const {
+    return mContent.c_str();
+}
+
+ssize_t ParsedMessage::parse(const char *data, size_t size, bool noMoreData) {
+    if (size == 0) {
+        return -1;
+    }
+
+    ssize_t lastDictIndex = -1;
+
+    size_t offset = 0;
+    while (offset < size) {
+        size_t lineEndOffset = offset;
+        while (lineEndOffset + 1 < size
+                && (data[lineEndOffset] != '\r'
+                        || data[lineEndOffset + 1] != '\n')) {
+            ++lineEndOffset;
+        }
+
+        if (lineEndOffset + 1 >= size) {
+            return -1;
+        }
+
+        AString line(&data[offset], lineEndOffset - offset);
+
+        if (offset == 0) {
+            // Special handling for the request/status line.
+
+            mDict.add(AString("_"), line);
+            offset = lineEndOffset + 2;
+
+            continue;
+        }
+
+        if (lineEndOffset == offset) {
+            offset += 2;
+            break;
+        }
+
+        if (line.c_str()[0] == ' ' || line.c_str()[0] == '\t') {
+            // Support for folded header values.
+
+            if (lastDictIndex >= 0) {
+                // Otherwise it's malformed since the first header line
+                // cannot continue anything...
+
+                AString &value = mDict.editValueAt(lastDictIndex);
+                value.append(line);
+            }
+
+            offset = lineEndOffset + 2;
+            continue;
+        }
+
+        ssize_t colonPos = line.find(":");
+        if (colonPos >= 0) {
+            AString key(line, 0, colonPos);
+            key.trim();
+            key.tolower();
+
+            line.erase(0, colonPos + 1);
+
+            lastDictIndex = mDict.add(key, line);
+        }
+
+        offset = lineEndOffset + 2;
+    }
+
+    for (size_t i = 0; i < mDict.size(); ++i) {
+        mDict.editValueAt(i).trim();
+    }
+
+    // Found the end of headers.
+
+    int32_t contentLength;
+    if (!findInt32("content-length", &contentLength) || contentLength < 0) {
+        contentLength = 0;
+    }
+
+    size_t totalLength = offset + contentLength;
+
+    if (size < totalLength) {
+        return -1;
+    }
+
+    mContent.setTo(&data[offset], contentLength);
+
+    return totalLength;
+}
+
+void ParsedMessage::getRequestField(size_t index, AString *field) const {
+    AString line;
+    CHECK(findString("_", &line));
+
+    size_t prevOffset = 0;
+    size_t offset = 0;
+    for (size_t i = 0; i <= index; ++i) {
+        ssize_t spacePos = line.find(" ", offset);
+
+        if (spacePos < 0) {
+            spacePos = line.size();
+        }
+
+        prevOffset = offset;
+        offset = spacePos + 1;
+    }
+
+    field->setTo(line, prevOffset, offset - prevOffset - 1);
+}
+
+bool ParsedMessage::getStatusCode(int32_t *statusCode) const {
+    AString statusCodeString;
+    getRequestField(1, &statusCodeString);
+
+    char *end;
+    *statusCode = strtol(statusCodeString.c_str(), &end, 10);
+
+    if (*end != '\0' || end == statusCodeString.c_str()
+            || (*statusCode) < 100 || (*statusCode) > 999) {
+        *statusCode = 0;
+        return false;
+    }
+
+    return true;
+}
+
+AString ParsedMessage::debugString() const {
+    AString line;
+    CHECK(findString("_", &line));
+
+    line.append("\n");
+
+    for (size_t i = 0; i < mDict.size(); ++i) {
+        const AString &key = mDict.keyAt(i);
+        const AString &value = mDict.valueAt(i);
+
+        if (key == AString("_")) {
+            continue;
+        }
+
+        line.append(key);
+        line.append(": ");
+        line.append(value);
+        line.append("\n");
+    }
+
+    line.append("\n");
+    line.append(mContent);
+
+    return line;
+}
+
+// static
+bool ParsedMessage::GetAttribute(
+        const char *s, const char *key, AString *value) {
+    value->clear();
+
+    size_t keyLen = strlen(key);
+
+    for (;;) {
+        while (isspace(*s)) {
+            ++s;
+        }
+
+        const char *colonPos = strchr(s, ';');
+
+        size_t len =
+            (colonPos == NULL) ? strlen(s) : colonPos - s;
+
+        if (len >= keyLen + 1 && s[keyLen] == '=' && !strncmp(s, key, keyLen)) {
+            value->setTo(&s[keyLen + 1], len - keyLen - 1);
+            return true;
+        }
+
+        if (colonPos == NULL) {
+            return false;
+        }
+
+        s = colonPos + 1;
+    }
+}
+
+// static
+bool ParsedMessage::GetInt32Attribute(
+        const char *s, const char *key, int32_t *value) {
+    AString stringValue;
+    if (!GetAttribute(s, key, &stringValue)) {
+        *value = 0;
+        return false;
+    }
+
+    char *end;
+    *value = strtol(stringValue.c_str(), &end, 10);
+
+    if (end == stringValue.c_str() || *end != '\0') {
+        *value = 0;
+        return false;
+    }
+
+    return true;
+}
+
+}  // namespace android
+
diff --git a/media/libstagefright/wifi-display/ParsedMessage.h b/media/libstagefright/wifi-display/ParsedMessage.h
new file mode 100644
index 0000000..00f578f
--- /dev/null
+++ b/media/libstagefright/wifi-display/ParsedMessage.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2012, 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.
+ */
+
+#include <media/stagefright/foundation/ABase.h>
+#include <media/stagefright/foundation/AString.h>
+#include <utils/KeyedVector.h>
+#include <utils/RefBase.h>
+
+namespace android {
+
+struct ParsedMessage : public RefBase {
+    static sp<ParsedMessage> Parse(
+            const char *data, size_t size, bool noMoreData, size_t *length);
+
+    bool findString(const char *name, AString *value) const;
+    bool findInt32(const char *name, int32_t *value) const;
+
+    const char *getContent() const;
+
+    void getRequestField(size_t index, AString *field) const;
+    bool getStatusCode(int32_t *statusCode) const;
+
+    AString debugString() const;
+
+    static bool GetAttribute(const char *s, const char *key, AString *value);
+
+    static bool GetInt32Attribute(
+            const char *s, const char *key, int32_t *value);
+
+
+protected:
+    virtual ~ParsedMessage();
+
+private:
+    KeyedVector<AString, AString> mDict;
+    AString mContent;
+
+    ParsedMessage();
+
+    ssize_t parse(const char *data, size_t size, bool noMoreData);
+
+    DISALLOW_EVIL_CONSTRUCTORS(ParsedMessage);
+};
+
+}  // namespace android
diff --git a/media/libstagefright/wifi-display/udptest.cpp b/media/libstagefright/wifi-display/udptest.cpp
new file mode 100644
index 0000000..1cd82c3
--- /dev/null
+++ b/media/libstagefright/wifi-display/udptest.cpp
@@ -0,0 +1,355 @@
+/*
+ * Copyright 2012, 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_NEBUG 0
+#define LOG_TAG "udptest"
+#include <utils/Log.h>
+
+#include "ANetworkSession.h"
+
+#include <binder/ProcessState.h>
+#include <media/stagefright/foundation/ABuffer.h>
+#include <media/stagefright/foundation/ADebug.h>
+#include <media/stagefright/foundation/AHandler.h>
+#include <media/stagefright/foundation/ALooper.h>
+#include <media/stagefright/foundation/AMessage.h>
+#include <media/stagefright/Utils.h>
+
+namespace android {
+
+struct TestHandler : public AHandler {
+    TestHandler(const sp<ANetworkSession> &netSession);
+
+    void startServer(unsigned localPort);
+    void startClient(const char *remoteHost, unsigned remotePort);
+
+protected:
+    virtual ~TestHandler();
+
+    virtual void onMessageReceived(const sp<AMessage> &msg);
+
+private:
+    enum {
+        kWhatStartServer,
+        kWhatStartClient,
+        kWhatUDPNotify,
+        kWhatSendPacket,
+    };
+
+    sp<ANetworkSession> mNetSession;
+
+    bool mIsServer;
+    bool mConnected;
+    int32_t mUDPSession;
+    uint32_t mSeqNo;
+    double mTotalTimeUs;
+    int32_t mCount;
+
+    void postSendPacket(int64_t delayUs = 0ll);
+
+    DISALLOW_EVIL_CONSTRUCTORS(TestHandler);
+};
+
+TestHandler::TestHandler(const sp<ANetworkSession> &netSession)
+    : mNetSession(netSession),
+      mIsServer(false),
+      mConnected(false),
+      mUDPSession(0),
+      mSeqNo(0),
+      mTotalTimeUs(0.0),
+      mCount(0) {
+}
+
+TestHandler::~TestHandler() {
+}
+
+void TestHandler::startServer(unsigned localPort) {
+    sp<AMessage> msg = new AMessage(kWhatStartServer, id());
+    msg->setInt32("localPort", localPort);
+    msg->post();
+}
+
+void TestHandler::startClient(const char *remoteHost, unsigned remotePort) {
+    sp<AMessage> msg = new AMessage(kWhatStartClient, id());
+    msg->setString("remoteHost", remoteHost);
+    msg->setInt32("remotePort", remotePort);
+    msg->post();
+}
+
+void TestHandler::onMessageReceived(const sp<AMessage> &msg) {
+    switch (msg->what()) {
+        case kWhatStartClient:
+        {
+            AString remoteHost;
+            CHECK(msg->findString("remoteHost", &remoteHost));
+
+            int32_t remotePort;
+            CHECK(msg->findInt32("remotePort", &remotePort));
+
+            sp<AMessage> notify = new AMessage(kWhatUDPNotify, id());
+
+            CHECK_EQ((status_t)OK,
+                     mNetSession->createUDPSession(
+                         0 /* localPort */,
+                         remoteHost.c_str(),
+                         remotePort,
+                         notify,
+                         &mUDPSession));
+
+            postSendPacket();
+            break;
+        }
+
+        case kWhatStartServer:
+        {
+            mIsServer = true;
+
+            int32_t localPort;
+            CHECK(msg->findInt32("localPort", &localPort));
+
+            sp<AMessage> notify = new AMessage(kWhatUDPNotify, id());
+
+            CHECK_EQ((status_t)OK,
+                     mNetSession->createUDPSession(
+                         localPort, notify, &mUDPSession));
+
+            break;
+        }
+
+        case kWhatSendPacket:
+        {
+            char buffer[12];
+            memset(buffer, 0, sizeof(buffer));
+
+            buffer[0] = mSeqNo >> 24;
+            buffer[1] = (mSeqNo >> 16) & 0xff;
+            buffer[2] = (mSeqNo >> 8) & 0xff;
+            buffer[3] = mSeqNo & 0xff;
+            ++mSeqNo;
+
+            int64_t nowUs = ALooper::GetNowUs();
+            buffer[4] = nowUs >> 56;
+            buffer[5] = (nowUs >> 48) & 0xff;
+            buffer[6] = (nowUs >> 40) & 0xff;
+            buffer[7] = (nowUs >> 32) & 0xff;
+            buffer[8] = (nowUs >> 24) & 0xff;
+            buffer[9] = (nowUs >> 16) & 0xff;
+            buffer[10] = (nowUs >> 8) & 0xff;
+            buffer[11] = nowUs & 0xff;
+
+            CHECK_EQ((status_t)OK,
+                     mNetSession->sendRequest(
+                         mUDPSession, buffer, sizeof(buffer)));
+
+            postSendPacket(20000ll);
+            break;
+        }
+
+        case kWhatUDPNotify:
+        {
+            int32_t reason;
+            CHECK(msg->findInt32("reason", &reason));
+
+            switch (reason) {
+                case ANetworkSession::kWhatError:
+                {
+                    int32_t sessionID;
+                    CHECK(msg->findInt32("sessionID", &sessionID));
+
+                    int32_t err;
+                    CHECK(msg->findInt32("err", &err));
+
+                    AString detail;
+                    CHECK(msg->findString("detail", &detail));
+
+                    ALOGE("An error occurred in session %d (%d, '%s/%s').",
+                          sessionID,
+                          err,
+                          detail.c_str(),
+                          strerror(-err));
+
+                    mNetSession->destroySession(sessionID);
+                    break;
+                }
+
+                case ANetworkSession::kWhatDatagram:
+                {
+                    int32_t sessionID;
+                    CHECK(msg->findInt32("sessionID", &sessionID));
+
+                    sp<ABuffer> data;
+                    CHECK(msg->findBuffer("data", &data));
+
+                    if (mIsServer) {
+                        if (!mConnected) {
+                            AString fromAddr;
+                            CHECK(msg->findString("fromAddr", &fromAddr));
+
+                            int32_t fromPort;
+                            CHECK(msg->findInt32("fromPort", &fromPort));
+
+                            CHECK_EQ((status_t)OK,
+                                     mNetSession->connectUDPSession(
+                                         mUDPSession, fromAddr.c_str(), fromPort));
+
+                            mConnected = true;
+                        }
+
+                        int64_t nowUs = ALooper::GetNowUs();
+
+                        sp<ABuffer> buffer = new ABuffer(data->size() + 8);
+                        memcpy(buffer->data(), data->data(), data->size());
+
+                        uint8_t *ptr = buffer->data() + data->size();
+
+                        *ptr++ = nowUs >> 56;
+                        *ptr++ = (nowUs >> 48) & 0xff;
+                        *ptr++ = (nowUs >> 40) & 0xff;
+                        *ptr++ = (nowUs >> 32) & 0xff;
+                        *ptr++ = (nowUs >> 24) & 0xff;
+                        *ptr++ = (nowUs >> 16) & 0xff;
+                        *ptr++ = (nowUs >> 8) & 0xff;
+                        *ptr++ = nowUs & 0xff;
+
+                        CHECK_EQ((status_t)OK,
+                                 mNetSession->sendRequest(
+                                     mUDPSession, buffer->data(), buffer->size()));
+                    } else {
+                        CHECK_EQ(data->size(), 20u);
+
+                        uint32_t seqNo = U32_AT(data->data());
+                        int64_t t1 = U64_AT(data->data() + 4);
+                        int64_t t2 = U64_AT(data->data() + 12);
+
+                        int64_t t3;
+                        CHECK(data->meta()->findInt64("arrivalTimeUs", &t3));
+
+#if 0
+                        printf("roundtrip seqNo %u, time = %lld us\n",
+                               seqNo, t3 - t1);
+#else
+                        mTotalTimeUs += t3 - t1;
+                        ++mCount;
+                        printf("avg. roundtrip time %.2f us\n", mTotalTimeUs / mCount);
+#endif
+                    }
+                    break;
+                }
+
+                default:
+                    TRESPASS();
+            }
+
+            break;
+        }
+
+        default:
+            TRESPASS();
+    }
+}
+
+void TestHandler::postSendPacket(int64_t delayUs) {
+    (new AMessage(kWhatSendPacket, id()))->post(delayUs);
+}
+
+}  // namespace android
+
+static void usage(const char *me) {
+    fprintf(stderr,
+            "usage: %s -c host[:port]\tconnect to test server\n"
+            "           -l            \tcreate a test server\n",
+            me);
+}
+
+int main(int argc, char **argv) {
+    using namespace android;
+
+    ProcessState::self()->startThreadPool();
+
+    int32_t localPort = -1;
+    int32_t connectToPort = -1;
+    AString connectToHost;
+
+    int res;
+    while ((res = getopt(argc, argv, "hc:l:")) >= 0) {
+        switch (res) {
+            case 'c':
+            {
+                const char *colonPos = strrchr(optarg, ':');
+
+                if (colonPos == NULL) {
+                    connectToHost = optarg;
+                    connectToPort = 49152;
+                } else {
+                    connectToHost.setTo(optarg, colonPos - optarg);
+
+                    char *end;
+                    connectToPort = strtol(colonPos + 1, &end, 10);
+
+                    if (*end != '\0' || end == colonPos + 1
+                            || connectToPort < 1 || connectToPort > 65535) {
+                        fprintf(stderr, "Illegal port specified.\n");
+                        exit(1);
+                    }
+                }
+                break;
+            }
+
+            case 'l':
+            {
+                char *end;
+                localPort = strtol(optarg, &end, 10);
+
+                if (*end != '\0' || end == optarg
+                        || localPort < 1 || localPort > 65535) {
+                    fprintf(stderr, "Illegal port specified.\n");
+                    exit(1);
+                }
+                break;
+            }
+
+            case '?':
+            case 'h':
+                usage(argv[0]);
+                exit(1);
+        }
+    }
+
+    if (localPort < 0 && connectToPort < 0) {
+        fprintf(stderr,
+                "You need to select either client or server mode.\n");
+        exit(1);
+    }
+
+    sp<ANetworkSession> netSession = new ANetworkSession;
+    netSession->start();
+
+    sp<ALooper> looper = new ALooper;
+
+    sp<TestHandler> handler = new TestHandler(netSession);
+    looper->registerHandler(handler);
+
+    if (localPort >= 0) {
+        handler->startServer(localPort);
+    } else {
+        handler->startClient(connectToHost.c_str(), connectToPort);
+    }
+
+    looper->start(true /* runOnCallingThread */);
+
+    return 0;
+}
+