| // Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| #include "platform/globals.h" |
| #if defined(TARGET_OS_LINUX) |
| |
| #include "bin/eventhandler.h" |
| |
| #include <errno.h> // NOLINT |
| #include <pthread.h> // NOLINT |
| #include <stdio.h> // NOLINT |
| #include <string.h> // NOLINT |
| #include <sys/epoll.h> // NOLINT |
| #include <sys/stat.h> // NOLINT |
| #include <sys/timerfd.h> // NOLINT |
| #include <unistd.h> // NOLINT |
| #include <fcntl.h> // NOLINT |
| |
| #include "bin/dartutils.h" |
| #include "bin/fdutils.h" |
| #include "bin/log.h" |
| #include "bin/socket.h" |
| #include "platform/thread.h" |
| #include "platform/utils.h" |
| |
| |
| namespace dart { |
| namespace bin { |
| |
| static const int kInterruptMessageSize = sizeof(InterruptMessage); |
| static const int kTimerId = -1; |
| static const int kShutdownId = -2; |
| |
| |
| intptr_t SocketData::GetPollEvents() { |
| // Do not ask for EPOLLERR and EPOLLHUP explicitly as they are |
| // triggered anyway. |
| intptr_t events = 0; |
| if ((mask_ & (1 << kInEvent)) != 0) { |
| events |= EPOLLIN; |
| } |
| if ((mask_ & (1 << kOutEvent)) != 0) { |
| events |= EPOLLOUT; |
| } |
| return events; |
| } |
| |
| |
| // Unregister the file descriptor for a SocketData structure with epoll. |
| static void RemoveFromEpollInstance(intptr_t epoll_fd_, SocketData* sd) { |
| VOID_NO_RETRY_EXPECTED(epoll_ctl(epoll_fd_, |
| EPOLL_CTL_DEL, |
| sd->fd(), |
| NULL)); |
| } |
| |
| |
| static void AddToEpollInstance(intptr_t epoll_fd_, SocketData* sd) { |
| struct epoll_event event; |
| event.events = EPOLLRDHUP | sd->GetPollEvents(); |
| if (!sd->IsListeningSocket()) { |
| event.events |= EPOLLET; |
| } |
| event.data.ptr = sd; |
| int status = NO_RETRY_EXPECTED(epoll_ctl(epoll_fd_, |
| EPOLL_CTL_ADD, |
| sd->fd(), |
| &event)); |
| if (status == -1) { |
| // Epoll does not accept the file descriptor. It could be due to |
| // already closed file descriptor, or unuspported devices, such |
| // as /dev/null. In such case, mark the file descriptor as closed, |
| // so dart will handle it accordingly. |
| DartUtils::PostInt32(sd->port(), 1 << kCloseEvent); |
| } |
| } |
| |
| |
| EventHandlerImplementation::EventHandlerImplementation() |
| : socket_map_(&HashMap::SamePointerValue, 16) { |
| intptr_t result; |
| result = NO_RETRY_EXPECTED(pipe(interrupt_fds_)); |
| if (result != 0) { |
| FATAL("Pipe creation failed"); |
| } |
| FDUtils::SetNonBlocking(interrupt_fds_[0]); |
| FDUtils::SetCloseOnExec(interrupt_fds_[0]); |
| FDUtils::SetCloseOnExec(interrupt_fds_[1]); |
| shutdown_ = false; |
| // The initial size passed to epoll_create is ignore on newer (>= |
| // 2.6.8) Linux versions |
| static const int kEpollInitialSize = 64; |
| epoll_fd_ = NO_RETRY_EXPECTED(epoll_create(kEpollInitialSize)); |
| if (epoll_fd_ == -1) { |
| FATAL1("Failed creating epoll file descriptor: %i", errno); |
| } |
| FDUtils::SetCloseOnExec(epoll_fd_); |
| // Register the interrupt_fd with the epoll instance. |
| struct epoll_event event; |
| event.events = EPOLLIN; |
| event.data.ptr = NULL; |
| int status = NO_RETRY_EXPECTED(epoll_ctl(epoll_fd_, |
| EPOLL_CTL_ADD, |
| interrupt_fds_[0], |
| &event)); |
| if (status == -1) { |
| FATAL("Failed adding interrupt fd to epoll instance"); |
| } |
| timer_fd_ = NO_RETRY_EXPECTED(timerfd_create(CLOCK_REALTIME, TFD_CLOEXEC)); |
| if (timer_fd_ == -1) { |
| FATAL1("Failed creating timerfd file descriptor: %i", errno); |
| } |
| // Register the timer_fd_ with the epoll instance. |
| event.events = EPOLLIN; |
| event.data.fd = timer_fd_; |
| status = NO_RETRY_EXPECTED(epoll_ctl(epoll_fd_, |
| EPOLL_CTL_ADD, |
| timer_fd_, |
| &event)); |
| if (status == -1) { |
| FATAL2( |
| "Failed adding timerfd fd(%i) to epoll instance: %i", timer_fd_, errno); |
| } |
| } |
| |
| |
| EventHandlerImplementation::~EventHandlerImplementation() { |
| VOID_TEMP_FAILURE_RETRY(close(epoll_fd_)); |
| VOID_TEMP_FAILURE_RETRY(close(timer_fd_)); |
| VOID_TEMP_FAILURE_RETRY(close(interrupt_fds_[0])); |
| VOID_TEMP_FAILURE_RETRY(close(interrupt_fds_[1])); |
| } |
| |
| |
| SocketData* EventHandlerImplementation::GetSocketData(intptr_t fd, |
| bool is_listening) { |
| ASSERT(fd >= 0); |
| HashMap::Entry* entry = socket_map_.Lookup( |
| GetHashmapKeyFromFd(fd), GetHashmapHashFromFd(fd), true); |
| ASSERT(entry != NULL); |
| SocketData* sd = reinterpret_cast<SocketData*>(entry->value); |
| if (sd == NULL) { |
| // If there is no data in the hash map for this file descriptor a |
| // new SocketData for the file descriptor is inserted. |
| if (is_listening) { |
| sd = new ListeningSocketData(fd); |
| } else { |
| sd = new SocketData(fd); |
| } |
| entry->value = sd; |
| } |
| ASSERT(fd == sd->fd()); |
| return sd; |
| } |
| |
| |
| void EventHandlerImplementation::WakeupHandler(intptr_t id, |
| Dart_Port dart_port, |
| int64_t data) { |
| InterruptMessage msg; |
| msg.id = id; |
| msg.dart_port = dart_port; |
| msg.data = data; |
| // WriteToBlocking will write up to 512 bytes atomically, and since our msg |
| // is smaller than 512, we don't need a thread lock. |
| // See: http://linux.die.net/man/7/pipe, section 'Pipe_buf'. |
| ASSERT(kInterruptMessageSize < PIPE_BUF); |
| intptr_t result = |
| FDUtils::WriteToBlocking(interrupt_fds_[1], &msg, kInterruptMessageSize); |
| if (result != kInterruptMessageSize) { |
| if (result == -1) { |
| perror("Interrupt message failure:"); |
| } |
| FATAL1("Interrupt message failure. Wrote %" Pd " bytes.", result); |
| } |
| } |
| |
| |
| void EventHandlerImplementation::HandleInterruptFd() { |
| const intptr_t MAX_MESSAGES = kInterruptMessageSize; |
| InterruptMessage msg[MAX_MESSAGES]; |
| ssize_t bytes = TEMP_FAILURE_RETRY_NO_SIGNAL_BLOCKER( |
| read(interrupt_fds_[0], msg, MAX_MESSAGES * kInterruptMessageSize)); |
| for (ssize_t i = 0; i < bytes / kInterruptMessageSize; i++) { |
| if (msg[i].id == kTimerId) { |
| timeout_queue_.UpdateTimeout(msg[i].dart_port, msg[i].data); |
| struct itimerspec it; |
| memset(&it, 0, sizeof(it)); |
| if (timeout_queue_.HasTimeout()) { |
| int64_t millis = timeout_queue_.CurrentTimeout(); |
| it.it_value.tv_sec = millis / 1000; |
| it.it_value.tv_nsec = (millis % 1000) * 1000000; |
| } |
| VOID_NO_RETRY_EXPECTED( |
| timerfd_settime(timer_fd_, TFD_TIMER_ABSTIME, &it, NULL)); |
| } else if (msg[i].id == kShutdownId) { |
| shutdown_ = true; |
| } else { |
| SocketData* sd = GetSocketData( |
| msg[i].id, (msg[i].data & (1 << kListeningSocket)) != 0); |
| if ((msg[i].data & (1 << kShutdownReadCommand)) != 0) { |
| ASSERT(msg[i].data == (1 << kShutdownReadCommand)); |
| ASSERT(!sd->IsListeningSocket()); |
| // Close the socket for reading. |
| VOID_NO_RETRY_EXPECTED(shutdown(sd->fd(), SHUT_RD)); |
| } else if ((msg[i].data & (1 << kShutdownWriteCommand)) != 0) { |
| ASSERT(msg[i].data == (1 << kShutdownWriteCommand)); |
| ASSERT(!sd->IsListeningSocket()); |
| // Close the socket for writing. |
| VOID_NO_RETRY_EXPECTED(shutdown(sd->fd(), SHUT_WR)); |
| } else if ((msg[i].data & (1 << kCloseCommand)) != 0) { |
| ASSERT(msg[i].data == (1 << kCloseCommand)); |
| // Close the socket and free system resources and move on to |
| // next message. |
| if (sd->RemovePort(msg[i].dart_port)) { |
| RemoveFromEpollInstance(epoll_fd_, sd); |
| intptr_t fd = sd->fd(); |
| sd->Close(); |
| socket_map_.Remove(GetHashmapKeyFromFd(fd), GetHashmapHashFromFd(fd)); |
| delete sd; |
| } |
| DartUtils::PostInt32(msg[i].dart_port, 1 << kDestroyedEvent); |
| } else if ((msg[i].data & (1 << kReturnTokenCommand)) != 0) { |
| int count = msg[i].data & ((1 << kReturnTokenCommand) - 1); |
| if (sd->ReturnToken(msg[i].dart_port, count)) { |
| AddToEpollInstance(epoll_fd_, sd); |
| } |
| } else { |
| // Setup events to wait for. |
| if (sd->AddPort(msg[i].dart_port)) { |
| sd->SetMask(msg[i].data); |
| AddToEpollInstance(epoll_fd_, sd); |
| } |
| } |
| } |
| } |
| } |
| |
| #ifdef DEBUG_POLL |
| static void PrintEventMask(intptr_t fd, intptr_t events) { |
| Log::Print("%d ", fd); |
| if ((events & EPOLLIN) != 0) Log::Print("EPOLLIN "); |
| if ((events & EPOLLPRI) != 0) Log::Print("EPOLLPRI "); |
| if ((events & EPOLLOUT) != 0) Log::Print("EPOLLOUT "); |
| if ((events & EPOLLERR) != 0) Log::Print("EPOLLERR "); |
| if ((events & EPOLLHUP) != 0) Log::Print("EPOLLHUP "); |
| if ((events & EPOLLRDHUP) != 0) Log::Print("EPOLLRDHUP "); |
| int all_events = EPOLLIN | EPOLLPRI | EPOLLOUT | |
| EPOLLERR | EPOLLHUP | EPOLLRDHUP; |
| if ((events & ~all_events) != 0) { |
| Log::Print("(and %08x) ", events & ~all_events); |
| } |
| Log::Print("(available %d) ", FDUtils::AvailableBytes(fd)); |
| |
| Log::Print("\n"); |
| } |
| #endif |
| |
| intptr_t EventHandlerImplementation::GetPollEvents(intptr_t events, |
| SocketData* sd) { |
| #ifdef DEBUG_POLL |
| PrintEventMask(sd->fd(), events); |
| #endif |
| if (events & EPOLLERR) { |
| // Return error only if EPOLLIN is present. |
| return (events & EPOLLIN) ? (1 << kErrorEvent) : 0; |
| } |
| intptr_t event_mask = 0; |
| if (events & EPOLLIN) event_mask |= (1 << kInEvent); |
| if (events & EPOLLOUT) event_mask |= (1 << kOutEvent); |
| if (events & (EPOLLHUP | EPOLLRDHUP)) event_mask |= (1 << kCloseEvent); |
| return event_mask; |
| } |
| |
| |
| void EventHandlerImplementation::HandleEvents(struct epoll_event* events, |
| int size) { |
| bool interrupt_seen = false; |
| for (int i = 0; i < size; i++) { |
| if (events[i].data.ptr == NULL) { |
| interrupt_seen = true; |
| } else if (events[i].data.fd == timer_fd_) { |
| int64_t val; |
| VOID_TEMP_FAILURE_RETRY_NO_SIGNAL_BLOCKER( |
| read(timer_fd_, &val, sizeof(val))); |
| if (timeout_queue_.HasTimeout()) { |
| DartUtils::PostNull(timeout_queue_.CurrentPort()); |
| timeout_queue_.RemoveCurrent(); |
| } |
| } else { |
| SocketData* sd = reinterpret_cast<SocketData*>(events[i].data.ptr); |
| intptr_t event_mask = GetPollEvents(events[i].events, sd); |
| if (event_mask != 0) { |
| Dart_Port port = sd->port(); |
| if (sd->TakeToken()) { |
| // Took last token, remove from epoll. |
| RemoveFromEpollInstance(epoll_fd_, sd); |
| } |
| ASSERT(port != 0); |
| DartUtils::PostInt32(port, event_mask); |
| } |
| } |
| } |
| if (interrupt_seen) { |
| // Handle after socket events, so we avoid closing a socket before we handle |
| // the current events. |
| HandleInterruptFd(); |
| } |
| } |
| |
| |
| void EventHandlerImplementation::Poll(uword args) { |
| ThreadSignalBlocker signal_blocker(SIGPROF); |
| static const intptr_t kMaxEvents = 16; |
| struct epoll_event events[kMaxEvents]; |
| EventHandler* handler = reinterpret_cast<EventHandler*>(args); |
| EventHandlerImplementation* handler_impl = &handler->delegate_; |
| ASSERT(handler_impl != NULL); |
| while (!handler_impl->shutdown_) { |
| intptr_t result = TEMP_FAILURE_RETRY_NO_SIGNAL_BLOCKER( |
| epoll_wait(handler_impl->epoll_fd_, events, kMaxEvents, -1)); |
| ASSERT(EAGAIN == EWOULDBLOCK); |
| if (result <= 0) { |
| if (errno != EWOULDBLOCK) { |
| perror("Poll failed"); |
| } |
| } else { |
| handler_impl->HandleEvents(events, result); |
| } |
| } |
| delete handler; |
| } |
| |
| |
| void EventHandlerImplementation::Start(EventHandler* handler) { |
| int result = dart::Thread::Start(&EventHandlerImplementation::Poll, |
| reinterpret_cast<uword>(handler)); |
| if (result != 0) { |
| FATAL1("Failed to start event handler thread %d", result); |
| } |
| } |
| |
| |
| void EventHandlerImplementation::Shutdown() { |
| SendData(kShutdownId, 0, 0); |
| } |
| |
| |
| void EventHandlerImplementation::SendData(intptr_t id, |
| Dart_Port dart_port, |
| int64_t data) { |
| WakeupHandler(id, dart_port, data); |
| } |
| |
| |
| void* EventHandlerImplementation::GetHashmapKeyFromFd(intptr_t fd) { |
| // The hashmap does not support keys with value 0. |
| return reinterpret_cast<void*>(fd + 1); |
| } |
| |
| |
| uint32_t EventHandlerImplementation::GetHashmapHashFromFd(intptr_t fd) { |
| // The hashmap does not support keys with value 0. |
| return dart::Utils::WordHash(fd + 1); |
| } |
| |
| } // namespace bin |
| } // namespace dart |
| |
| #endif // defined(TARGET_OS_LINUX) |
