diff --git a/libs/utils/Looper.cpp b/libs/utils/Looper.cpp
new file mode 100644
index 0000000..fd287da
--- /dev/null
+++ b/libs/utils/Looper.cpp
@@ -0,0 +1,368 @@
+//
+// Copyright 2010 The Android Open Source Project
+//
+// A looper implementation based on epoll().
+//
+#define LOG_TAG "Looper"
+
+//#define LOG_NDEBUG 0
+
+// Debugs poll and wake interactions.
+#define DEBUG_POLL_AND_WAKE 0
+
+// Debugs callback registration and invocation.
+#define DEBUG_CALLBACKS 0
+
+#include <cutils/log.h>
+#include <utils/Looper.h>
+#include <utils/Timers.h>
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/epoll.h>
+
+
+namespace android {
+
+static pthread_mutex_t gTLSMutex = PTHREAD_MUTEX_INITIALIZER;
+static bool gHaveTLS = false;
+static pthread_key_t gTLS = 0;
+
+// Hint for number of file descriptors to be associated with the epoll instance.
+static const int EPOLL_SIZE_HINT = 8;
+
+// Maximum number of file descriptors for which to retrieve poll events each iteration.
+static const int EPOLL_MAX_EVENTS = 16;
+
+Looper::Looper(bool allowNonCallbacks) :
+        mAllowNonCallbacks(allowNonCallbacks),
+        mResponseIndex(0) {
+    mEpollFd = epoll_create(EPOLL_SIZE_HINT);
+    LOG_ALWAYS_FATAL_IF(mEpollFd < 0, "Could not create epoll instance.  errno=%d", errno);
+
+    int wakeFds[2];
+    int result = pipe(wakeFds);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not create wake pipe.  errno=%d", errno);
+
+    mWakeReadPipeFd = wakeFds[0];
+    mWakeWritePipeFd = wakeFds[1];
+
+    result = fcntl(mWakeReadPipeFd, F_SETFL, O_NONBLOCK);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not make wake read pipe non-blocking.  errno=%d",
+            errno);
+
+    result = fcntl(mWakeWritePipeFd, F_SETFL, O_NONBLOCK);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not make wake write pipe non-blocking.  errno=%d",
+            errno);
+
+    struct epoll_event eventItem;
+    eventItem.events = EPOLLIN;
+    eventItem.data.fd = mWakeReadPipeFd;
+    result = epoll_ctl(mEpollFd, EPOLL_CTL_ADD, mWakeReadPipeFd, & eventItem);
+    LOG_ALWAYS_FATAL_IF(result != 0, "Could not add wake read pipe to epoll instance.  errno=%d",
+            errno);
+}
+
+Looper::~Looper() {
+    close(mWakeReadPipeFd);
+    close(mWakeWritePipeFd);
+    close(mEpollFd);
+}
+
+void Looper::threadDestructor(void *st) {
+    Looper* const self = static_cast<Looper*>(st);
+    if (self != NULL) {
+        self->decStrong((void*)threadDestructor);
+    }
+}
+
+void Looper::setForThread(const sp<Looper>& looper) {
+    sp<Looper> old = getForThread(); // also has side-effect of initializing TLS
+
+    if (looper != NULL) {
+        looper->incStrong((void*)threadDestructor);
+    }
+
+    pthread_setspecific(gTLS, looper.get());
+
+    if (old != NULL) {
+        old->decStrong((void*)threadDestructor);
+    }
+}
+
+sp<Looper> Looper::getForThread() {
+    if (!gHaveTLS) {
+        pthread_mutex_lock(&gTLSMutex);
+        if (pthread_key_create(&gTLS, threadDestructor) != 0) {
+            pthread_mutex_unlock(&gTLSMutex);
+            return NULL;
+        }
+        gHaveTLS = true;
+        pthread_mutex_unlock(&gTLSMutex);
+    }
+
+    return (Looper*)pthread_getspecific(gTLS);
+}
+
+sp<Looper> Looper::prepare(int opts) {
+    bool allowNonCallbacks = opts & ALOOPER_PREPARE_ALLOW_NON_CALLBACKS;
+    sp<Looper> looper = Looper::getForThread();
+    if (looper == NULL) {
+        looper = new Looper(allowNonCallbacks);
+        Looper::setForThread(looper);
+    }
+    if (looper->getAllowNonCallbacks() != allowNonCallbacks) {
+        LOGW("Looper already prepared for this thread with a different value for the "
+                "ALOOPER_PREPARE_ALLOW_NON_CALLBACKS option.");
+    }
+    return looper;
+}
+
+bool Looper::getAllowNonCallbacks() const {
+    return mAllowNonCallbacks;
+}
+
+int Looper::pollOnce(int timeoutMillis, int* outFd, int* outEvents, void** outData) {
+    int result = 0;
+    for (;;) {
+        while (mResponseIndex < mResponses.size()) {
+            const Response& response = mResponses.itemAt(mResponseIndex++);
+            if (! response.request.callback) {
+#if DEBUG_POLL_AND_WAKE
+                LOGD("%p ~ pollOnce - returning signalled identifier %d: "
+                        "fd=%d, events=0x%x, data=%p", this,
+                        response.request.ident, response.request.fd,
+                        response.events, response.request.data);
+#endif
+                if (outFd != NULL) *outFd = response.request.fd;
+                if (outEvents != NULL) *outEvents = response.events;
+                if (outData != NULL) *outData = response.request.data;
+                return response.request.ident;
+            }
+        }
+
+        if (result != 0) {
+#if DEBUG_POLL_AND_WAKE
+            LOGD("%p ~ pollOnce - returning result %d", this, result);
+#endif
+            if (outFd != NULL) *outFd = 0;
+            if (outEvents != NULL) *outEvents = NULL;
+            if (outData != NULL) *outData = NULL;
+            return result;
+        }
+
+        result = pollInner(timeoutMillis);
+    }
+}
+
+int Looper::pollInner(int timeoutMillis) {
+#if DEBUG_POLL_AND_WAKE
+    LOGD("%p ~ pollOnce - waiting: timeoutMillis=%d", this, timeoutMillis);
+#endif
+    struct epoll_event eventItems[EPOLL_MAX_EVENTS];
+    int eventCount = epoll_wait(mEpollFd, eventItems, EPOLL_MAX_EVENTS, timeoutMillis);
+    if (eventCount < 0) {
+        if (errno != EINTR) {
+            LOGW("Poll failed with an unexpected error, errno=%d", errno);
+        }
+        return ALOOPER_POLL_ERROR;
+    }
+
+    if (eventCount == 0) {
+#if DEBUG_POLL_AND_WAKE
+        LOGD("%p ~ pollOnce - timeout", this);
+#endif
+        return ALOOPER_POLL_TIMEOUT;
+    }
+
+    int result = ALOOPER_POLL_WAKE;
+    mResponses.clear();
+    mResponseIndex = 0;
+
+#if DEBUG_POLL_AND_WAKE
+    LOGD("%p ~ pollOnce - handling events from %d fds", this, eventCount);
+#endif
+    { // acquire lock
+        AutoMutex _l(mLock);
+        for (int i = 0; i < eventCount; i++) {
+            int fd = eventItems[i].data.fd;
+            uint32_t epollEvents = eventItems[i].events;
+            if (fd == mWakeReadPipeFd) {
+                if (epollEvents & EPOLLIN) {
+#if DEBUG_POLL_AND_WAKE
+                    LOGD("%p ~ pollOnce - awoken", this);
+#endif
+                    char buffer[16];
+                    ssize_t nRead;
+                    do {
+                        nRead = read(mWakeReadPipeFd, buffer, sizeof(buffer));
+                    } while (nRead == sizeof(buffer));
+                } else {
+                    LOGW("Ignoring unexpected epoll events 0x%x on wake read pipe.", epollEvents);
+                }
+            } else {
+                ssize_t requestIndex = mRequests.indexOfKey(fd);
+                if (requestIndex >= 0) {
+                    int events = 0;
+                    if (epollEvents & EPOLLIN) events |= ALOOPER_EVENT_INPUT;
+                    if (epollEvents & EPOLLOUT) events |= ALOOPER_EVENT_OUTPUT;
+                    if (epollEvents & EPOLLERR) events |= ALOOPER_EVENT_ERROR;
+                    if (epollEvents & EPOLLHUP) events |= ALOOPER_EVENT_HANGUP;
+
+                    Response response;
+                    response.events = events;
+                    response.request = mRequests.valueAt(requestIndex);
+                    mResponses.push(response);
+                } else {
+                    LOGW("Ignoring unexpected epoll events 0x%x on fd %d that is "
+                            "no longer registered.", epollEvents, fd);
+                }
+            }
+        }
+    }
+
+    for (size_t i = 0; i < mResponses.size(); i++) {
+        const Response& response = mResponses.itemAt(i);
+        if (response.request.callback) {
+#if DEBUG_POLL_AND_WAKE || DEBUG_CALLBACKS
+            LOGD("%p ~ pollOnce - invoking callback: fd=%d, events=0x%x, data=%p", this,
+                    response.request.fd, response.events, response.request.data);
+#endif
+            int callbackResult = response.request.callback(
+                    response.request.fd, response.events, response.request.data);
+            if (callbackResult == 0) {
+                removeFd(response.request.fd);
+            }
+
+            result = ALOOPER_POLL_CALLBACK;
+        }
+    }
+    return result;
+}
+
+int Looper::pollAll(int timeoutMillis, int* outFd, int* outEvents, void** outData) {
+    if (timeoutMillis <= 0) {
+        int result;
+        do {
+            result = pollOnce(timeoutMillis, outFd, outEvents, outData);
+        } while (result == ALOOPER_POLL_CALLBACK);
+        return result;
+    } else {
+        nsecs_t endTime = systemTime(SYSTEM_TIME_MONOTONIC)
+                + milliseconds_to_nanoseconds(timeoutMillis);
+
+        for (;;) {
+            int result = pollOnce(timeoutMillis, outFd, outEvents, outData);
+            if (result != ALOOPER_POLL_CALLBACK) {
+                return result;
+            }
+
+            nsecs_t timeoutNanos = endTime - systemTime(SYSTEM_TIME_MONOTONIC);
+            if (timeoutNanos <= 0) {
+                return ALOOPER_POLL_TIMEOUT;
+            }
+
+            timeoutMillis = int(nanoseconds_to_milliseconds(timeoutNanos + 999999LL));
+        }
+    }
+}
+
+void Looper::wake() {
+#if DEBUG_POLL_AND_WAKE
+    LOGD("%p ~ wake", this);
+#endif
+
+    ssize_t nWrite = write(mWakeWritePipeFd, "W", 1);
+    if (nWrite != 1) {
+        if (errno != EAGAIN) {
+            LOGW("Could not write wake signal, errno=%d", errno);
+        }
+    }
+}
+
+int Looper::addFd(int fd, int ident, int events, ALooper_callbackFunc callback, void* data) {
+#if DEBUG_CALLBACKS
+    LOGD("%p ~ addFd - fd=%d, ident=%d, events=0x%x, callback=%p, data=%p", this, fd, ident,
+            events, callback, data);
+#endif
+
+    int epollEvents = 0;
+    if (events & ALOOPER_EVENT_INPUT) epollEvents |= EPOLLIN;
+    if (events & ALOOPER_EVENT_OUTPUT) epollEvents |= EPOLLOUT;
+    if (events & ALOOPER_EVENT_ERROR) epollEvents |= EPOLLERR;
+    if (events & ALOOPER_EVENT_HANGUP) epollEvents |= EPOLLHUP;
+
+    if (epollEvents == 0) {
+        LOGE("Invalid attempt to set a callback with no selected poll events.");
+        return -1;
+    }
+
+    if (! callback) {
+        if (! mAllowNonCallbacks) {
+            LOGE("Invalid attempt to set NULL callback but not allowed for this looper.");
+            return -1;
+        }
+
+        if (ident < 0) {
+            LOGE("Invalid attempt to set NULL callback with ident <= 0.");
+            return -1;
+        }
+    }
+
+    { // acquire lock
+        AutoMutex _l(mLock);
+
+        Request request;
+        request.fd = fd;
+        request.ident = ident;
+        request.callback = callback;
+        request.data = data;
+
+        struct epoll_event eventItem;
+        eventItem.events = epollEvents;
+        eventItem.data.fd = fd;
+
+        ssize_t requestIndex = mRequests.indexOfKey(fd);
+        if (requestIndex < 0) {
+            int epollResult = epoll_ctl(mEpollFd, EPOLL_CTL_ADD, fd, & eventItem);
+            if (epollResult < 0) {
+                LOGE("Error adding epoll events for fd %d, errno=%d", fd, errno);
+                return -1;
+            }
+            mRequests.add(fd, request);
+        } else {
+            int epollResult = epoll_ctl(mEpollFd, EPOLL_CTL_MOD, fd, & eventItem);
+            if (epollResult < 0) {
+                LOGE("Error modifying epoll events for fd %d, errno=%d", fd, errno);
+                return -1;
+            }
+            mRequests.replaceValueAt(requestIndex, request);
+        }
+    } // release lock
+    return 1;
+}
+
+int Looper::removeFd(int fd) {
+#if DEBUG_CALLBACKS
+    LOGD("%p ~ removeFd - fd=%d", this, fd);
+#endif
+
+    { // acquire lock
+        AutoMutex _l(mLock);
+        ssize_t requestIndex = mRequests.indexOfKey(fd);
+        if (requestIndex < 0) {
+            return 0;
+        }
+
+        int epollResult = epoll_ctl(mEpollFd, EPOLL_CTL_DEL, fd, NULL);
+        if (epollResult < 0) {
+            LOGE("Error removing epoll events for fd %d, errno=%d", fd, errno);
+            return -1;
+        }
+
+        mRequests.removeItemsAt(requestIndex);
+    } // request lock
+    return 1;
+}
+
+} // namespace android