diff --git a/adbconnection/adbconnection.cc b/adbconnection/adbconnection.cc
new file mode 100644
index 0000000..2a9982a
--- /dev/null
+++ b/adbconnection/adbconnection.cc
@@ -0,0 +1,639 @@
+/*
+ * Copyright (C) 2017 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 <array>
+
+#include "adbconnection.h"
+
+#include "android-base/endian.h"
+#include "android-base/stringprintf.h"
+#include "base/logging.h"
+#include "base/macros.h"
+#include "base/mutex.h"
+#include "java_vm_ext.h"
+#include "jni_env_ext.h"
+#include "mirror/throwable.h"
+#include "nativehelper/ScopedLocalRef.h"
+#include "runtime-inl.h"
+#include "runtime_callbacks.h"
+#include "scoped_thread_state_change-inl.h"
+#include "well_known_classes.h"
+
+#include "jdwp/jdwp_priv.h"
+
+#include "fd_transport.h"
+
+#include "poll.h"
+
+#ifdef ART_TARGET_ANDROID
+#include "cutils/sockets.h"
+#endif
+
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/eventfd.h>
+#include <jni.h>
+
+namespace adbconnection {
+
+using dt_fd_forward::kListenStartMessage;
+using dt_fd_forward::kListenEndMessage;
+using dt_fd_forward::kAcceptMessage;
+using dt_fd_forward::kCloseMessage;
+
+using android::base::StringPrintf;
+
+static constexpr int kEventfdLocked = 0;
+static constexpr int kEventfdUnlocked = 1;
+static constexpr int kControlSockSendTimeout = 10;
+
+static AdbConnectionState* gState;
+
+static bool IsDebuggingPossible() {
+  // TODO We need to do this on IsJdwpAllowed not IsDebuggable in order to support userdebug
+  // workloads. For now we will only allow it when we are debuggable so that testing is easier.
+  return art::Runtime::Current()->IsJavaDebuggable() && art::Dbg::IsJdwpAllowed();
+}
+
+// Begin running the debugger.
+void AdbConnectionDebuggerController::StartDebugger() {
+  if (IsDebuggingPossible()) {
+    connection_->StartDebuggerThreads();
+  } else {
+    LOG(ERROR) << "Not starting debugger since process cannot load the jdwp agent.";
+  }
+}
+
+// The debugger should begin shutting down since the runtime is ending. We don't actually do
+// anything here. The real shutdown has already happened as far as the agent is concerned.
+void AdbConnectionDebuggerController::StopDebugger() { }
+
+bool AdbConnectionDebuggerController::IsDebuggerConfigured() {
+  return IsDebuggingPossible() && !art::Runtime::Current()->GetJdwpOptions().empty();
+}
+
+void AdbConnectionDdmCallback::DdmPublishChunk(uint32_t type,
+                                               const art::ArrayRef<const uint8_t>& data) {
+  connection_->PublishDdmData(type, data);
+}
+
+class ScopedEventFdLock {
+ public:
+  explicit ScopedEventFdLock(int fd) : fd_(fd), data_(0) {
+    TEMP_FAILURE_RETRY(read(fd_, &data_, sizeof(data_)));
+  }
+
+  ~ScopedEventFdLock() {
+    TEMP_FAILURE_RETRY(write(fd_, &data_, sizeof(data_)));
+  }
+
+ private:
+  int fd_;
+  uint64_t data_;
+};
+
+AdbConnectionState::AdbConnectionState(const std::string& agent_name)
+  : agent_name_(agent_name),
+    controller_(this),
+    ddm_callback_(this),
+    sleep_event_fd_(-1),
+    control_sock_(-1),
+    local_agent_control_sock_(-1),
+    remote_agent_control_sock_(-1),
+    adb_connection_socket_(-1),
+    adb_write_event_fd_(-1),
+    shutting_down_(false),
+    agent_loaded_(false),
+    agent_listening_(false),
+    next_ddm_id_(1) {
+  // Setup the addr.
+  control_addr_.controlAddrUn.sun_family = AF_UNIX;
+  control_addr_len_ = sizeof(control_addr_.controlAddrUn.sun_family) + sizeof(kJdwpControlName) - 1;
+  memcpy(control_addr_.controlAddrUn.sun_path, kJdwpControlName, sizeof(kJdwpControlName) - 1);
+
+  // Add the startup callback.
+  art::ScopedObjectAccess soa(art::Thread::Current());
+  art::Runtime::Current()->GetRuntimeCallbacks()->AddDebuggerControlCallback(&controller_);
+}
+
+static jobject CreateAdbConnectionThread(art::Thread* thr) {
+  JNIEnv* env = thr->GetJniEnv();
+  // Move to native state to talk with the jnienv api.
+  art::ScopedThreadStateChange stsc(thr, art::kNative);
+  ScopedLocalRef<jstring> thr_name(env, env->NewStringUTF(kAdbConnectionThreadName));
+  ScopedLocalRef<jobject> thr_group(
+      env,
+      env->GetStaticObjectField(art::WellKnownClasses::java_lang_ThreadGroup,
+                                art::WellKnownClasses::java_lang_ThreadGroup_systemThreadGroup));
+  return env->NewObject(art::WellKnownClasses::java_lang_Thread,
+                        art::WellKnownClasses::java_lang_Thread_init,
+                        thr_group.get(),
+                        thr_name.get(),
+                        /*Priority*/ 0,
+                        /*Daemon*/ true);
+}
+
+struct CallbackData {
+  AdbConnectionState* this_;
+  jobject thr_;
+};
+
+static void* CallbackFunction(void* vdata) {
+  std::unique_ptr<CallbackData> data(reinterpret_cast<CallbackData*>(vdata));
+  art::Thread* self = art::Thread::Attach(kAdbConnectionThreadName,
+                                          true,
+                                          data->thr_);
+  CHECK(self != nullptr) << "threads_being_born_ should have ensured thread could be attached.";
+  // The name in Attach() is only for logging. Set the thread name. This is important so
+  // that the thread is no longer seen as starting up.
+  {
+    art::ScopedObjectAccess soa(self);
+    self->SetThreadName(kAdbConnectionThreadName);
+  }
+
+  // Release the peer.
+  JNIEnv* env = self->GetJniEnv();
+  env->DeleteGlobalRef(data->thr_);
+  data->thr_ = nullptr;
+  {
+    // The StartThreadBirth was called in the parent thread. We let the runtime know we are up
+    // before going into the provided code.
+    art::MutexLock mu(self, *art::Locks::runtime_shutdown_lock_);
+    art::Runtime::Current()->EndThreadBirth();
+  }
+  data->this_->RunPollLoop(self);
+  int detach_result = art::Runtime::Current()->GetJavaVM()->DetachCurrentThread();
+  CHECK_EQ(detach_result, 0);
+
+  return nullptr;
+}
+
+void AdbConnectionState::StartDebuggerThreads() {
+  // First do all the final setup we need.
+  CHECK_EQ(adb_write_event_fd_.get(), -1);
+  CHECK_EQ(sleep_event_fd_.get(), -1);
+  CHECK_EQ(local_agent_control_sock_.get(), -1);
+  CHECK_EQ(remote_agent_control_sock_.get(), -1);
+
+  sleep_event_fd_.reset(eventfd(kEventfdLocked, EFD_CLOEXEC));
+  CHECK_NE(sleep_event_fd_.get(), -1) << "Unable to create wakeup eventfd.";
+  adb_write_event_fd_.reset(eventfd(kEventfdUnlocked, EFD_CLOEXEC));
+  CHECK_NE(adb_write_event_fd_.get(), -1) << "Unable to create write-lock eventfd.";
+
+  {
+    art::ScopedObjectAccess soa(art::Thread::Current());
+    art::Runtime::Current()->GetRuntimeCallbacks()->AddDdmCallback(&ddm_callback_);
+  }
+  // Setup the socketpair we use to talk to the agent.
+  bool has_sockets;
+  do {
+    has_sockets = android::base::Socketpair(AF_UNIX,
+                                            SOCK_SEQPACKET | SOCK_CLOEXEC,
+                                            0,
+                                            &local_agent_control_sock_,
+                                            &remote_agent_control_sock_);
+  } while (!has_sockets && errno == EINTR);
+  if (!has_sockets) {
+    PLOG(FATAL) << "Unable to create socketpair for agent control!";
+  }
+
+  // Next start the threads.
+  art::Thread* self = art::Thread::Current();
+  art::ScopedObjectAccess soa(self);
+  {
+    art::Runtime* runtime = art::Runtime::Current();
+    art::MutexLock mu(self, *art::Locks::runtime_shutdown_lock_);
+    if (runtime->IsShuttingDownLocked()) {
+      // The runtime is shutting down so we cannot create new threads. This shouldn't really happen.
+      LOG(ERROR) << "The runtime is shutting down when we are trying to start up the debugger!";
+      return;
+    }
+    runtime->StartThreadBirth();
+  }
+  ScopedLocalRef<jobject> thr(soa.Env(), CreateAdbConnectionThread(soa.Self()));
+  pthread_t pthread;
+  std::unique_ptr<CallbackData> data(new CallbackData { this, soa.Env()->NewGlobalRef(thr.get()) });
+  int pthread_create_result = pthread_create(&pthread,
+                                             nullptr,
+                                             &CallbackFunction,
+                                             data.get());
+  if (pthread_create_result != 0) {
+    // If the create succeeded the other thread will call EndThreadBirth.
+    art::Runtime* runtime = art::Runtime::Current();
+    soa.Env()->DeleteGlobalRef(data->thr_);
+    LOG(ERROR) << "Failed to create thread for adb-jdwp connection manager!";
+    art::MutexLock mu(art::Thread::Current(), *art::Locks::runtime_shutdown_lock_);
+    runtime->EndThreadBirth();
+    return;
+  }
+  data.release();
+}
+
+static bool FlagsSet(int16_t data, int16_t flags) {
+  return (data & flags) == flags;
+}
+
+void AdbConnectionState::CloseFds() {
+  // Lock the write_event_fd so that concurrent PublishDdms will see that the connection is closed.
+  ScopedEventFdLock lk(adb_write_event_fd_);
+  // shutdown(adb_connection_socket_, SHUT_RDWR);
+  adb_connection_socket_.reset();
+}
+
+uint32_t AdbConnectionState::NextDdmId() {
+  // Just have a normal counter but always set the sign bit.
+  return (next_ddm_id_++) | 0x80000000;
+}
+
+void AdbConnectionState::PublishDdmData(uint32_t type, const art::ArrayRef<const uint8_t>& data) {
+  // Get the write_event early to fail fast.
+  ScopedEventFdLock lk(adb_write_event_fd_);
+  if (adb_connection_socket_ == -1) {
+    LOG(WARNING) << "Not sending ddms data of type "
+                 << StringPrintf("%c%c%c%c",
+                                 static_cast<char>(type >> 24),
+                                 static_cast<char>(type >> 16),
+                                 static_cast<char>(type >> 8),
+                                 static_cast<char>(type)) << " due to no connection!";
+    // Adb is not connected.
+    return;
+  }
+
+  // the adb_write_event_fd_ will ensure that the adb_connection_socket_ will not go away until
+  // after we have sent our data.
+  static constexpr uint32_t kDdmPacketHeaderSize =
+      kJDWPHeaderLen       // jdwp command packet size
+      + sizeof(uint32_t)   // Type
+      + sizeof(uint32_t);  // length
+  std::array<uint8_t, kDdmPacketHeaderSize> pkt;
+  uint8_t* pkt_data = pkt.data();
+
+  // Write the length first.
+  *reinterpret_cast<uint32_t*>(pkt_data) = htonl(kDdmPacketHeaderSize + data.size());
+  pkt_data += sizeof(uint32_t);
+
+  // Write the id next;
+  *reinterpret_cast<uint32_t*>(pkt_data) = htonl(NextDdmId());
+  pkt_data += sizeof(uint32_t);
+
+  // next the flags. (0 for cmd packet because DDMS).
+  *(pkt_data++) = 0;
+  // Now the cmd-set
+  *(pkt_data++) = kJDWPDdmCmdSet;
+  // Now the command
+  *(pkt_data++) = kJDWPDdmCmd;
+
+  // now the type.
+  *reinterpret_cast<uint32_t*>(pkt_data) = htonl(type);
+  pkt_data += sizeof(uint32_t);
+
+  // Now the data.size()
+  *reinterpret_cast<uint32_t*>(pkt_data) = htonl(data.size());
+  pkt_data += sizeof(uint32_t);
+
+  static uint32_t constexpr kIovSize = 2;
+  struct iovec iovs[kIovSize] = {
+    { pkt.data(), pkt.size() },
+    { const_cast<uint8_t*>(data.data()), data.size() },
+  };
+  // now pkt_header has the header.
+  // use writev to send the actual data.
+  ssize_t res = TEMP_FAILURE_RETRY(writev(adb_connection_socket_, iovs, kIovSize));
+  if (static_cast<size_t>(res) != (kDdmPacketHeaderSize + data.size())) {
+    PLOG(ERROR) << StringPrintf("Failed to send DDMS packet %c%c%c%c to debugger (%zd of %zu)",
+                                static_cast<char>(type >> 24),
+                                static_cast<char>(type >> 16),
+                                static_cast<char>(type >> 8),
+                                static_cast<char>(type),
+                                res, data.size() + kDdmPacketHeaderSize);
+  } else {
+    VLOG(jdwp) << StringPrintf("sent DDMS packet %c%c%c%c to debugger %zu",
+                               static_cast<char>(type >> 24),
+                               static_cast<char>(type >> 16),
+                               static_cast<char>(type >> 8),
+                               static_cast<char>(type),
+                               data.size() + kDdmPacketHeaderSize);
+  }
+}
+
+void AdbConnectionState::SendAgentFds() {
+  // TODO
+  DCHECK(!sent_agent_fds_);
+  char dummy = '!';
+  union {
+    cmsghdr cm;
+    char buffer[CMSG_SPACE(dt_fd_forward::FdSet::kDataLength)];
+  } cm_un;
+  iovec iov;
+  iov.iov_base       = &dummy;
+  iov.iov_len        = 1;
+
+  msghdr msg;
+  msg.msg_name       = nullptr;
+  msg.msg_namelen    = 0;
+  msg.msg_iov        = &iov;
+  msg.msg_iovlen     = 1;
+  msg.msg_flags      = 0;
+  msg.msg_control    = cm_un.buffer;
+  msg.msg_controllen = sizeof(cm_un.buffer);
+
+  cmsghdr* cmsg = CMSG_FIRSTHDR(&msg);
+  cmsg->cmsg_len   = CMSG_LEN(dt_fd_forward::FdSet::kDataLength);
+  cmsg->cmsg_level = SOL_SOCKET;
+  cmsg->cmsg_type  = SCM_RIGHTS;
+
+  // Duplicate the fds before sending them.
+  android::base::unique_fd read_fd(dup(adb_connection_socket_));
+  CHECK_NE(read_fd.get(), -1) << "Failed to dup read_fd_: " << strerror(errno);
+  android::base::unique_fd write_fd(dup(adb_connection_socket_));
+  CHECK_NE(write_fd.get(), -1) << "Failed to dup write_fd: " << strerror(errno);
+  android::base::unique_fd write_lock_fd(dup(adb_write_event_fd_));
+  CHECK_NE(write_lock_fd.get(), -1) << "Failed to dup write_lock_fd: " << strerror(errno);
+
+  dt_fd_forward::FdSet {
+    read_fd.get(), write_fd.get(), write_lock_fd.get()
+  }.WriteData(CMSG_DATA(cmsg));
+
+  int res = TEMP_FAILURE_RETRY(sendmsg(local_agent_control_sock_, &msg, MSG_EOR));
+  if (res < 0) {
+    PLOG(ERROR) << "Failed to send agent adb connection fds.";
+  } else {
+    sent_agent_fds_ = true;
+    VLOG(jdwp) << "Fds have been sent to jdwp agent!";
+  }
+}
+
+android::base::unique_fd AdbConnectionState::ReadFdFromAdb() {
+  // We don't actually care about the data that is sent. We do need to receive something though.
+  char dummy = '!';
+  union {
+    cmsghdr cm;
+    char buffer[CMSG_SPACE(sizeof(int))];
+  } cm_un;
+
+  iovec iov;
+  iov.iov_base       = &dummy;
+  iov.iov_len        = 1;
+
+  msghdr msg;
+  msg.msg_name       = nullptr;
+  msg.msg_namelen    = 0;
+  msg.msg_iov        = &iov;
+  msg.msg_iovlen     = 1;
+  msg.msg_flags      = 0;
+  msg.msg_control    = cm_un.buffer;
+  msg.msg_controllen = sizeof(cm_un.buffer);
+
+  cmsghdr* cmsg = CMSG_FIRSTHDR(&msg);
+  cmsg->cmsg_len   = msg.msg_controllen;
+  cmsg->cmsg_level = SOL_SOCKET;
+  cmsg->cmsg_type  = SCM_RIGHTS;
+  (reinterpret_cast<int*>(CMSG_DATA(cmsg)))[0] = -1;
+
+  int rc = TEMP_FAILURE_RETRY(recvmsg(control_sock_, &msg, 0));
+
+  if (rc <= 0) {
+    PLOG(WARNING) << "Receiving file descriptor from ADB failed (socket " << control_sock_ << ")";
+    return android::base::unique_fd(-1);
+  } else {
+    VLOG(jdwp) << "Fds have been received from ADB!";
+  }
+
+  return android::base::unique_fd((reinterpret_cast<int*>(CMSG_DATA(cmsg)))[0]);
+}
+
+bool AdbConnectionState::SetupAdbConnection() {
+  int        sleep_ms     = 500;
+  const int  sleep_max_ms = 2*1000;
+  char       buff[sizeof(pid_t) + 1];
+
+  android::base::unique_fd sock(socket(AF_UNIX, SOCK_SEQPACKET, 0));
+  if (sock < 0) {
+    PLOG(ERROR) << "Could not create ADB control socket";
+    return false;
+  }
+  struct timeval timeout;
+  timeout.tv_sec = kControlSockSendTimeout;
+  timeout.tv_usec = 0;
+  setsockopt(sock, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(timeout));
+  snprintf(buff, sizeof(buff), "%04x", getpid());
+  buff[sizeof(pid_t)] = 0;
+
+  while (!shutting_down_) {
+    // If adbd isn't running, because USB debugging was disabled or
+    // perhaps the system is restarting it for "adb root", the
+    // connect() will fail.  We loop here forever waiting for it
+    // to come back.
+    //
+    // Waking up and polling every couple of seconds is generally a
+    // bad thing to do, but we only do this if the application is
+    // debuggable *and* adbd isn't running.  Still, for the sake
+    // of battery life, we should consider timing out and giving
+    // up after a few minutes in case somebody ships an app with
+    // the debuggable flag set.
+    int ret = connect(sock, &control_addr_.controlAddrPlain, control_addr_len_);
+    if (ret == 0) {
+      bool trusted = sock >= 0;
+#ifdef ART_TARGET_ANDROID
+      // Needed for socket_peer_is_trusted.
+      trusted = trusted && socket_peer_is_trusted(sock);
+#endif
+      if (!trusted) {
+        LOG(ERROR) << "adb socket is not trusted. Aborting connection.";
+        if (sock >= 0 && shutdown(sock, SHUT_RDWR)) {
+          PLOG(ERROR) << "trouble shutting down socket";
+        }
+        return false;
+      }
+      /* now try to send our pid to the ADB daemon */
+      ret = TEMP_FAILURE_RETRY(send(sock, buff, sizeof(pid_t), 0));
+      if (ret == sizeof(pid_t)) {
+        LOG(INFO) << "PID " << getpid() << " send to adb";
+        control_sock_ = std::move(sock);
+        return true;
+      } else {
+        PLOG(ERROR) << "Weird, can't send JDWP process pid to ADB. Aborting connection.";
+        return false;
+      }
+    } else {
+      PLOG(ERROR) << "Can't connect to ADB control socket. Will retry.";
+
+      usleep(sleep_ms * 1000);
+
+      sleep_ms += (sleep_ms >> 1);
+      if (sleep_ms > sleep_max_ms) {
+        sleep_ms = sleep_max_ms;
+      }
+    }
+  }
+  return false;
+}
+
+void AdbConnectionState::RunPollLoop(art::Thread* self) {
+  CHECK_EQ(self->GetState(), art::kNative);
+  art::Locks::mutator_lock_->AssertNotHeld(self);
+  self->SetState(art::kWaitingInMainDebuggerLoop);
+  // shutting_down_ set by StopDebuggerThreads
+  while (!shutting_down_) {
+    // First get the control_sock_ from adb if we don't have one. We only need to do this once.
+    if (control_sock_ == -1 && !SetupAdbConnection()) {
+      LOG(ERROR) << "Failed to setup adb connection.";
+      return;
+    }
+    while (!shutting_down_ && control_sock_ != -1) {
+      struct pollfd pollfds[4] = {
+        { sleep_event_fd_, POLLIN, 0 },
+        // -1 as an fd causes it to be ignored by poll
+        { (agent_loaded_ ? local_agent_control_sock_ : -1), POLLIN, 0 },
+        // Check for the control_sock_ actually going away. Only do this if we don't have an active
+        // connection.
+        { (adb_connection_socket_ == -1 ? control_sock_ : -1), POLLIN | POLLRDHUP, 0 },
+        // if we have not loaded the agent either the adb_connection_socket_ is -1 meaning we don't
+        // have a real connection yet or the socket through adb needs to be listened to for incoming
+        // data that the agent can handle.
+        { ((!agent_has_socket_ && !sent_agent_fds_) ? adb_connection_socket_ : -1), POLLIN, 0 }
+      };
+      int res = TEMP_FAILURE_RETRY(poll(pollfds, 4, -1));
+      if (res < 0) {
+        PLOG(ERROR) << "Failed to poll!";
+        return;
+      }
+      // We don't actually care about doing this we just use it to wake us up.
+      // const struct pollfd& sleep_event_poll     = pollfds[0];
+      const struct pollfd& agent_control_sock_poll = pollfds[1];
+      const struct pollfd& control_sock_poll       = pollfds[2];
+      const struct pollfd& adb_socket_poll         = pollfds[3];
+      if (FlagsSet(agent_control_sock_poll.revents, POLLIN)) {
+        DCHECK(agent_loaded_);
+        char buf[257];
+        res = TEMP_FAILURE_RETRY(recv(local_agent_control_sock_, buf, sizeof(buf) - 1, 0));
+        if (res < 0) {
+          PLOG(ERROR) << "Failed to read message from agent control socket! Retrying";
+          continue;
+        } else {
+          buf[res + 1] = '\0';
+          VLOG(jdwp) << "Local agent control sock has data: " << static_cast<const char*>(buf);
+        }
+        if (memcmp(kListenStartMessage, buf, sizeof(kListenStartMessage)) == 0) {
+          agent_listening_ = true;
+          if (adb_connection_socket_ != -1) {
+            SendAgentFds();
+          }
+        } else if (memcmp(kListenEndMessage, buf, sizeof(kListenEndMessage)) == 0) {
+          agent_listening_ = false;
+        } else if (memcmp(kCloseMessage, buf, sizeof(kCloseMessage)) == 0) {
+          CloseFds();
+          agent_has_socket_ = false;
+        } else if (memcmp(kAcceptMessage, buf, sizeof(kAcceptMessage)) == 0) {
+          agent_has_socket_ = true;
+          sent_agent_fds_ = false;
+        } else {
+          LOG(ERROR) << "Unknown message received from debugger! '" << std::string(buf) << "'";
+        }
+      } else if (FlagsSet(control_sock_poll.revents, POLLIN)) {
+        bool maybe_send_fds = false;
+        {
+          // Hold onto this lock so that concurrent ddm publishes don't try to use an illegal fd.
+          ScopedEventFdLock sefdl(adb_write_event_fd_);
+          android::base::unique_fd new_fd(ReadFdFromAdb());
+          if (new_fd == -1) {
+            // Something went wrong. We need to retry getting the control socket.
+            PLOG(ERROR) << "Something went wrong getting fds from adb. Retry!";
+            control_sock_.reset();
+            break;
+          } else if (adb_connection_socket_ != -1) {
+            // We already have a connection.
+            VLOG(jdwp) << "Ignoring second debugger. Accept then drop!";
+            if (new_fd >= 0) {
+              new_fd.reset();
+            }
+          } else {
+            VLOG(jdwp) << "Adb connection established with fd " << new_fd;
+            adb_connection_socket_ = std::move(new_fd);
+            maybe_send_fds = true;
+          }
+        }
+        if (maybe_send_fds && agent_loaded_ && agent_listening_) {
+          VLOG(jdwp) << "Sending fds as soon as we received them.";
+          SendAgentFds();
+        }
+      } else if (FlagsSet(control_sock_poll.revents, POLLRDHUP)) {
+        // The other end of the adb connection just dropped it.
+        // Reset the connection since we don't have an active socket through the adb server.
+        DCHECK(!agent_has_socket_) << "We shouldn't be doing anything if there is already a "
+                                   << "connection active";
+        control_sock_.reset();
+        break;
+      } else if (FlagsSet(adb_socket_poll.revents, POLLIN)) {
+        DCHECK(!agent_has_socket_);
+        if (!agent_loaded_) {
+          DCHECK(!agent_listening_);
+          // Load the agent now!
+          self->AssertNoPendingException();
+          art::Runtime::Current()->AttachAgent(MakeAgentArg());
+          if (self->IsExceptionPending()) {
+            LOG(ERROR) << "Failed to load agent " << agent_name_;
+            art::ScopedObjectAccess soa(self);
+            self->GetException()->Dump();
+            self->ClearException();
+            return;
+          }
+          agent_loaded_ = true;
+        } else if (agent_listening_ && !sent_agent_fds_) {
+          VLOG(jdwp) << "Sending agent fds again on data.";
+          SendAgentFds();
+        }
+      } else {
+        VLOG(jdwp) << "Woke up poll without anything to do!";
+      }
+    }
+  }
+}
+
+std::string AdbConnectionState::MakeAgentArg() {
+  // TODO Get this from something user settable?
+  const std::string& opts = art::Runtime::Current()->GetJdwpOptions();
+  return agent_name_ + "=" + opts + (opts.empty() ? "" : ",")
+      + "transport=dt_fd_forward,address=" + std::to_string(remote_agent_control_sock_);
+}
+
+void AdbConnectionState::StopDebuggerThreads() {
+  // The regular agent system will take care of unloading the agent (if needed).
+  shutting_down_ = true;
+  // Wakeup the poll loop.
+  uint64_t data = 1;
+  TEMP_FAILURE_RETRY(write(sleep_event_fd_, &data, sizeof(data)));
+}
+
+// The plugin initialization function.
+extern "C" bool ArtPlugin_Initialize() REQUIRES_SHARED(art::Locks::mutator_lock_) {
+  DCHECK(art::Runtime::Current()->GetJdwpProvider() == art::JdwpProvider::kAdbConnection);
+  // TODO Provide some way for apps to set this maybe?
+  gState = new AdbConnectionState(kDefaultJdwpAgentName);
+  CHECK(gState != nullptr);
+  return true;
+}
+
+extern "C" bool ArtPlugin_Deinitialize() {
+  CHECK(gState != nullptr);
+  // Just do this a second time?
+  // TODO I don't think this should be needed.
+  gState->StopDebuggerThreads();
+  delete gState;
+  return true;
+}
+
+}  // namespace adbconnection