#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if !defined(ARCADIA_BUILD) # include #endif #if defined(OS_DARWIN) # pragma GCC diagnostic ignored "-Wunused-macros" # define _XOPEN_SOURCE 700 // ucontext is not available without _XOPEN_SOURCE #endif #include DB::PipeFDs signal_pipe; /** Reset signal handler to the default and send signal to itself. * It's called from user signal handler to write core dump. */ static void call_default_signal_handler(int sig) { signal(sig, SIG_DFL); raise(sig); } const char * msan_strsignal(int sig) { // Apparently strsignal is not instrumented by MemorySanitizer, so we // have to unpoison it to avoid msan reports inside fmt library when we // print it. const char * signal_name = strsignal(sig); __msan_unpoison_string(signal_name); return signal_name; } static constexpr size_t max_query_id_size = 127; static const size_t signal_pipe_buf_size = sizeof(int) + sizeof(siginfo_t) + sizeof(ucontext_t) + sizeof(StackTrace) + sizeof(UInt32) + max_query_id_size + 1 /// query_id + varint encoded length + sizeof(void*); using signal_function = void(int, siginfo_t*, void*); static void writeSignalIDtoSignalPipe(int sig) { auto saved_errno = errno; /// We must restore previous value of errno in signal handler. char buf[signal_pipe_buf_size]; DB::WriteBufferFromFileDescriptor out(signal_pipe.fds_rw[1], signal_pipe_buf_size, buf); DB::writeBinary(sig, out); out.next(); errno = saved_errno; } /** Signal handler for HUP / USR1 */ static void closeLogsSignalHandler(int sig, siginfo_t *, void *) { writeSignalIDtoSignalPipe(sig); } static void terminateRequestedSignalHandler(int sig, siginfo_t *, void *) { writeSignalIDtoSignalPipe(sig); } /** Handler for "fault" or diagnostic signals. Send data about fault to separate thread to write into log. */ static void signalHandler(int sig, siginfo_t * info, void * context) { auto saved_errno = errno; /// We must restore previous value of errno in signal handler. char buf[signal_pipe_buf_size]; DB::WriteBufferFromFileDescriptorDiscardOnFailure out(signal_pipe.fds_rw[1], signal_pipe_buf_size, buf); const ucontext_t signal_context = *reinterpret_cast(context); const StackTrace stack_trace(signal_context); StringRef query_id = DB::CurrentThread::getQueryId(); /// This is signal safe. query_id.size = std::min(query_id.size, max_query_id_size); DB::writeBinary(sig, out); DB::writePODBinary(*info, out); DB::writePODBinary(signal_context, out); DB::writePODBinary(stack_trace, out); DB::writeBinary(UInt32(getThreadId()), out); DB::writeStringBinary(query_id, out); DB::writePODBinary(DB::current_thread, out); out.next(); if (sig != SIGTSTP) /// This signal is used for debugging. { /// The time that is usually enough for separate thread to print info into log. sleepForSeconds(10); call_default_signal_handler(sig); } errno = saved_errno; } /// Avoid link time dependency on DB/Interpreters - will use this function only when linked. __attribute__((__weak__)) void collectCrashLog( Int32 signal, UInt64 thread_id, const String & query_id, const StackTrace & stack_trace); /** The thread that read info about signal or std::terminate from pipe. * On HUP / USR1, close log files (for new files to be opened later). * On information about std::terminate, write it to log. * On other signals, write info to log. */ class SignalListener : public Poco::Runnable { public: enum Signals : int { StdTerminate = -1, StopThread = -2, SanitizerTrap = -3, }; explicit SignalListener(BaseDaemon & daemon_) : log(&Poco::Logger::get("BaseDaemon")) , daemon(daemon_) { } void run() override { char buf[signal_pipe_buf_size]; DB::ReadBufferFromFileDescriptor in(signal_pipe.fds_rw[0], signal_pipe_buf_size, buf); while (!in.eof()) { int sig = 0; DB::readBinary(sig, in); // We may log some specific signals afterwards, with different log // levels and more info, but for completeness we log all signals // here at trace level. // Don't use strsignal here, because it's not thread-safe. LOG_TRACE(log, "Received signal {}", sig); if (sig == Signals::StopThread) { LOG_INFO(log, "Stop SignalListener thread"); break; } else if (sig == SIGHUP || sig == SIGUSR1) { LOG_DEBUG(log, "Received signal to close logs."); BaseDaemon::instance().closeLogs(BaseDaemon::instance().logger()); LOG_INFO(log, "Opened new log file after received signal."); } else if (sig == Signals::StdTerminate) { UInt32 thread_num; std::string message; DB::readBinary(thread_num, in); DB::readBinary(message, in); onTerminate(message, thread_num); } else if (sig == SIGINT || sig == SIGQUIT || sig == SIGTERM) { daemon.handleSignal(sig); } else { siginfo_t info; ucontext_t context; StackTrace stack_trace(NoCapture{}); UInt32 thread_num; std::string query_id; DB::ThreadStatus * thread_ptr{}; if (sig != SanitizerTrap) { DB::readPODBinary(info, in); DB::readPODBinary(context, in); } DB::readPODBinary(stack_trace, in); DB::readBinary(thread_num, in); DB::readBinary(query_id, in); DB::readPODBinary(thread_ptr, in); /// This allows to receive more signals if failure happens inside onFault function. /// Example: segfault while symbolizing stack trace. std::thread([=, this] { onFault(sig, info, context, stack_trace, thread_num, query_id, thread_ptr); }).detach(); } } } private: Poco::Logger * log; BaseDaemon & daemon; void onTerminate(const std::string & message, UInt32 thread_num) const { LOG_FATAL(log, "(version {}{}, {}) (from thread {}) {}", VERSION_STRING, VERSION_OFFICIAL, daemon.build_id_info, thread_num, message); } void onFault( int sig, const siginfo_t & info, const ucontext_t & context, const StackTrace & stack_trace, UInt32 thread_num, const std::string & query_id, DB::ThreadStatus * thread_ptr) const { DB::ThreadStatus thread_status; /// Send logs from this thread to client if possible. /// It will allow client to see failure messages directly. if (thread_ptr) { if (auto logs_queue = thread_ptr->getInternalTextLogsQueue()) DB::CurrentThread::attachInternalTextLogsQueue(logs_queue, DB::LogsLevel::trace); } LOG_FATAL(log, "########################################"); if (query_id.empty()) { LOG_FATAL(log, "(version {}{}, {}) (from thread {}) (no query) Received signal {} ({})", VERSION_STRING, VERSION_OFFICIAL, daemon.build_id_info, thread_num, msan_strsignal(sig), sig); } else { LOG_FATAL(log, "(version {}{}, {}) (from thread {}) (query_id: {}) Received signal {} ({})", VERSION_STRING, VERSION_OFFICIAL, daemon.build_id_info, thread_num, query_id, msan_strsignal(sig), sig); } String error_message; if (sig != SanitizerTrap) error_message = signalToErrorMessage(sig, info, context); else error_message = "Sanitizer trap."; LOG_FATAL(log, error_message); if (stack_trace.getSize()) { /// Write bare stack trace (addresses) just in case if we will fail to print symbolized stack trace. /// NOTE This still require memory allocations and mutex lock inside logger. BTW we can also print it to stderr using write syscalls. std::stringstream bare_stacktrace; bare_stacktrace << "Stack trace:"; for (size_t i = stack_trace.getOffset(); i < stack_trace.getSize(); ++i) bare_stacktrace << ' ' << stack_trace.getFramePointers()[i]; LOG_FATAL(log, bare_stacktrace.str()); } /// Write symbolized stack trace line by line for better grep-ability. stack_trace.toStringEveryLine([&](const std::string & s) { LOG_FATAL(log, s); }); /// Write crash to system.crash_log table if available. if (collectCrashLog) collectCrashLog(sig, thread_num, query_id, stack_trace); /// Send crash report to developers (if configured) if (sig != SanitizerTrap) SentryWriter::onFault(sig, error_message, stack_trace); /// When everything is done, we will try to send these error messages to client. if (thread_ptr) thread_ptr->onFatalError(); } }; #if defined(SANITIZER) extern "C" void __sanitizer_set_death_callback(void (*)()); static void sanitizerDeathCallback() { /// Also need to send data via pipe. Otherwise it may lead to deadlocks or failures in printing diagnostic info. char buf[signal_pipe_buf_size]; DB::WriteBufferFromFileDescriptorDiscardOnFailure out(signal_pipe.fds_rw[1], signal_pipe_buf_size, buf); const StackTrace stack_trace; StringRef query_id = DB::CurrentThread::getQueryId(); query_id.size = std::min(query_id.size, max_query_id_size); int sig = SignalListener::SanitizerTrap; DB::writeBinary(sig, out); DB::writePODBinary(stack_trace, out); DB::writeBinary(UInt32(getThreadId()), out); DB::writeStringBinary(query_id, out); DB::writePODBinary(DB::current_thread, out); out.next(); /// The time that is usually enough for separate thread to print info into log. sleepForSeconds(10); } #endif /** To use with std::set_terminate. * Collects slightly more info than __gnu_cxx::__verbose_terminate_handler, * and send it to pipe. Other thread will read this info from pipe and asynchronously write it to log. * Look at libstdc++-v3/libsupc++/vterminate.cc for example. */ [[noreturn]] static void terminate_handler() { static thread_local bool terminating = false; if (terminating) abort(); terminating = true; std::string log_message; if (std::current_exception()) log_message = "Terminate called for uncaught exception:\n" + DB::getCurrentExceptionMessage(true); else log_message = "Terminate called without an active exception"; static const size_t buf_size = 1024; if (log_message.size() > buf_size - 16) log_message.resize(buf_size - 16); char buf[buf_size]; DB::WriteBufferFromFileDescriptor out(signal_pipe.fds_rw[1], buf_size, buf); DB::writeBinary(static_cast(SignalListener::StdTerminate), out); DB::writeBinary(UInt32(getThreadId()), out); DB::writeBinary(log_message, out); out.next(); abort(); } static std::string createDirectory(const std::string & file) { auto path = Poco::Path(file).makeParent(); if (path.toString().empty()) return ""; Poco::File(path).createDirectories(); return path.toString(); }; static bool tryCreateDirectories(Poco::Logger * logger, const std::string & path) { try { Poco::File(path).createDirectories(); return true; } catch (...) { LOG_WARNING(logger, "{}: when creating {}, {}", __PRETTY_FUNCTION__, path, DB::getCurrentExceptionMessage(true)); } return false; } void BaseDaemon::reloadConfiguration() { /** If the program is not run in daemon mode and 'config-file' is not specified, * then we use config from 'config.xml' file in current directory, * but will log to console (or use parameters --log-file, --errorlog-file from command line) * instead of using files specified in config.xml. * (It's convenient to log in console when you start server without any command line parameters.) */ config_path = config().getString("config-file", "config.xml"); DB::ConfigProcessor config_processor(config_path, false, true); config_processor.setConfigPath(Poco::Path(config_path).makeParent().toString()); loaded_config = config_processor.loadConfig(/* allow_zk_includes = */ true); if (last_configuration != nullptr) config().removeConfiguration(last_configuration); last_configuration = loaded_config.configuration.duplicate(); config().add(last_configuration, PRIO_DEFAULT, false); } BaseDaemon::BaseDaemon() = default; BaseDaemon::~BaseDaemon() { writeSignalIDtoSignalPipe(SignalListener::StopThread); signal_listener_thread.join(); signal_pipe.close(); } void BaseDaemon::terminate() { getTaskManager().cancelAll(); if (::raise(SIGTERM) != 0) throw Poco::SystemException("cannot terminate process"); } void BaseDaemon::kill() { dumpCoverageReportIfPossible(); pid.reset(); if (::raise(SIGKILL) != 0) throw Poco::SystemException("cannot kill process"); } void BaseDaemon::sleep(double seconds) { wakeup_event.reset(); wakeup_event.tryWait(seconds * 1000); } void BaseDaemon::wakeup() { wakeup_event.set(); } std::string BaseDaemon::getDefaultCorePath() const { return "/opt/cores/"; } void BaseDaemon::closeFDs() { #if defined(OS_FREEBSD) || defined(OS_DARWIN) Poco::File proc_path{"/dev/fd"}; #else Poco::File proc_path{"/proc/self/fd"}; #endif if (proc_path.isDirectory()) /// Hooray, proc exists { std::vector fds; /// in /proc/self/fd directory filenames are numeric file descriptors proc_path.list(fds); for (const auto & fd_str : fds) { int fd = DB::parse(fd_str); if (fd > 2 && fd != signal_pipe.fds_rw[0] && fd != signal_pipe.fds_rw[1]) ::close(fd); } } else { int max_fd = -1; #if defined(_SC_OPEN_MAX) max_fd = sysconf(_SC_OPEN_MAX); if (max_fd == -1) #endif max_fd = 256; /// bad fallback for (int fd = 3; fd < max_fd; ++fd) if (fd != signal_pipe.fds_rw[0] && fd != signal_pipe.fds_rw[1]) ::close(fd); } } namespace { /// In debug version on Linux, increase oom score so that clickhouse is killed /// first, instead of some service. Use a carefully chosen random score of 555: /// the maximum is 1000, and chromium uses 300 for its tab processes. Ignore /// whatever errors that occur, because it's just a debugging aid and we don't /// care if it breaks. #if defined(OS_LINUX) && !defined(NDEBUG) void debugIncreaseOOMScore() { const std::string new_score = "555"; try { DB::WriteBufferFromFile buf("/proc/self/oom_score_adj"); buf.write(new_score.c_str(), new_score.size()); } catch (const Poco::Exception & e) { LOG_WARNING(&Poco::Logger::root(), "Failed to adjust OOM score: '{}'.", e.displayText()); return; } LOG_INFO(&Poco::Logger::root(), "Set OOM score adjustment to {}", new_score); } #else void debugIncreaseOOMScore() {} #endif } void BaseDaemon::initialize(Application & self) { closeFDs(); task_manager = std::make_unique(); ServerApplication::initialize(self); /// now highest priority (lowest value) is PRIO_APPLICATION = -100, we want higher! argsToConfig(argv(), config(), PRIO_APPLICATION - 100); bool is_daemon = config().getBool("application.runAsDaemon", false); if (is_daemon) { /** When creating pid file and looking for config, will search for paths relative to the working path of the program when started. */ std::string path = Poco::Path(config().getString("application.path")).setFileName("").toString(); if (0 != chdir(path.c_str())) throw Poco::Exception("Cannot change directory to " + path); } reloadConfiguration(); /// This must be done before creation of any files (including logs). mode_t umask_num = 0027; if (config().has("umask")) { std::string umask_str = config().getString("umask"); std::stringstream stream; stream << umask_str; stream >> std::oct >> umask_num; } umask(umask_num); DB::ConfigProcessor(config_path).savePreprocessedConfig(loaded_config, ""); /// Write core dump on crash. { struct rlimit rlim; if (getrlimit(RLIMIT_CORE, &rlim)) throw Poco::Exception("Cannot getrlimit"); /// 1 GiB by default. If more - it writes to disk too long. rlim.rlim_cur = config().getUInt64("core_dump.size_limit", 1024 * 1024 * 1024); if (rlim.rlim_cur && setrlimit(RLIMIT_CORE, &rlim)) { /// It doesn't work under address/thread sanitizer. http://lists.llvm.org/pipermail/llvm-bugs/2013-April/027880.html std::cerr << "Cannot set max size of core file to " + std::to_string(rlim.rlim_cur) << std::endl; } } /// This must be done before any usage of DateLUT. In particular, before any logging. if (config().has("timezone")) { const std::string config_timezone = config().getString("timezone"); if (0 != setenv("TZ", config_timezone.data(), 1)) throw Poco::Exception("Cannot setenv TZ variable"); tzset(); DateLUT::setDefaultTimezone(config_timezone); } std::string log_path = config().getString("logger.log", ""); if (!log_path.empty()) log_path = Poco::Path(log_path).setFileName("").toString(); /** Redirect stdout, stderr to separate files in the log directory (or in the specified file). * Some libraries write to stderr in case of errors in debug mode, * and this output makes sense even if the program is run in daemon mode. * We have to do it before buildLoggers, for errors on logger initialization will be written to these files. * If logger.stderr is specified then stderr will be forcibly redirected to that file. */ if ((!log_path.empty() && is_daemon) || config().has("logger.stderr")) { std::string stderr_path = config().getString("logger.stderr", log_path + "/stderr.log"); if (!freopen(stderr_path.c_str(), "a+", stderr)) throw Poco::OpenFileException("Cannot attach stderr to " + stderr_path); /// Disable buffering for stderr setbuf(stderr, nullptr); } if ((!log_path.empty() && is_daemon) || config().has("logger.stdout")) { std::string stdout_path = config().getString("logger.stdout", log_path + "/stdout.log"); if (!freopen(stdout_path.c_str(), "a+", stdout)) throw Poco::OpenFileException("Cannot attach stdout to " + stdout_path); } /// Create pid file. if (config().has("pid")) pid.emplace(config().getString("pid"), DB::StatusFile::write_pid); /// Change path for logging. if (!log_path.empty()) { std::string path = createDirectory(log_path); if (is_daemon && chdir(path.c_str()) != 0) throw Poco::Exception("Cannot change directory to " + path); } else { if (is_daemon && chdir("/tmp") != 0) throw Poco::Exception("Cannot change directory to /tmp"); } // sensitive data masking rules are not used here buildLoggers(config(), logger(), self.commandName()); if (is_daemon) { /** Change working directory to the directory to write core dumps. * We have to do it after buildLoggers, because there is the case when config files was in current directory. */ std::string core_path = config().getString("core_path", ""); if (core_path.empty()) core_path = getDefaultCorePath(); tryCreateDirectories(&logger(), core_path); Poco::File cores = core_path; if (!(cores.exists() && cores.isDirectory())) { core_path = !log_path.empty() ? log_path : "/opt/"; tryCreateDirectories(&logger(), core_path); } if (0 != chdir(core_path.c_str())) throw Poco::Exception("Cannot change directory to " + core_path); } initializeTerminationAndSignalProcessing(); logRevision(); debugIncreaseOOMScore(); for (const auto & key : DB::getMultipleKeysFromConfig(config(), "", "graphite")) { graphite_writers.emplace(key, std::make_unique(key)); } } void BaseDaemon::initializeTerminationAndSignalProcessing() { SentryWriter::initialize(config()); std::set_terminate(terminate_handler); /// We want to avoid SIGPIPE when working with sockets and pipes, and just handle return value/errno instead. { sigset_t sig_set; if (sigemptyset(&sig_set) || sigaddset(&sig_set, SIGPIPE) || pthread_sigmask(SIG_BLOCK, &sig_set, nullptr)) throw Poco::Exception("Cannot block signal."); } /// Setup signal handlers. auto add_signal_handler = [](const std::vector & signals, signal_function handler) { struct sigaction sa; memset(&sa, 0, sizeof(sa)); sa.sa_sigaction = handler; sa.sa_flags = SA_SIGINFO; { #if defined(OS_DARWIN) sigemptyset(&sa.sa_mask); for (auto signal : signals) sigaddset(&sa.sa_mask, signal); #else if (sigemptyset(&sa.sa_mask)) throw Poco::Exception("Cannot set signal handler."); for (auto signal : signals) if (sigaddset(&sa.sa_mask, signal)) throw Poco::Exception("Cannot set signal handler."); #endif for (auto signal : signals) if (sigaction(signal, &sa, nullptr)) throw Poco::Exception("Cannot set signal handler."); } }; /// SIGTSTP is added for debugging purposes. To output a stack trace of any running thread at anytime. add_signal_handler({SIGABRT, SIGSEGV, SIGILL, SIGBUS, SIGSYS, SIGFPE, SIGPIPE, SIGTSTP}, signalHandler); add_signal_handler({SIGHUP, SIGUSR1}, closeLogsSignalHandler); add_signal_handler({SIGINT, SIGQUIT, SIGTERM}, terminateRequestedSignalHandler); #if defined(SANITIZER) __sanitizer_set_death_callback(sanitizerDeathCallback); #endif /// Set up Poco ErrorHandler for Poco Threads. static KillingErrorHandler killing_error_handler; Poco::ErrorHandler::set(&killing_error_handler); signal_pipe.setNonBlocking(); signal_pipe.tryIncreaseSize(1 << 20); signal_listener = std::make_unique(*this); signal_listener_thread.start(*signal_listener); #if defined(__ELF__) && !defined(__FreeBSD__) String build_id_hex = DB::SymbolIndex::instance().getBuildIDHex(); if (build_id_hex.empty()) build_id_info = "no build id"; else build_id_info = "build id: " + build_id_hex; #else build_id_info = "no build id"; #endif } void BaseDaemon::logRevision() const { Poco::Logger::root().information("Starting " + std::string{VERSION_FULL} + " with revision " + std::to_string(ClickHouseRevision::get()) + ", " + build_id_info + ", PID " + std::to_string(getpid())); } /// Makes server shutdown if at least one Poco::Task have failed. void BaseDaemon::exitOnTaskError() { Poco::Observer obs(*this, &BaseDaemon::handleNotification); getTaskManager().addObserver(obs); } /// Used for exitOnTaskError() void BaseDaemon::handleNotification(Poco::TaskFailedNotification *_tfn) { task_failed = true; Poco::AutoPtr fn(_tfn); Poco::Logger * lg = &(logger()); LOG_ERROR(lg, "Task '{}' failed. Daemon is shutting down. Reason - {}", fn->task()->name(), fn->reason().displayText()); ServerApplication::terminate(); } void BaseDaemon::defineOptions(Poco::Util::OptionSet & new_options) { new_options.addOption( Poco::Util::Option("config-file", "C", "load configuration from a given file") .required(false) .repeatable(false) .argument("") .binding("config-file")); new_options.addOption( Poco::Util::Option("log-file", "L", "use given log file") .required(false) .repeatable(false) .argument("") .binding("logger.log")); new_options.addOption( Poco::Util::Option("errorlog-file", "E", "use given log file for errors only") .required(false) .repeatable(false) .argument("") .binding("logger.errorlog")); new_options.addOption( Poco::Util::Option("pid-file", "P", "use given pidfile") .required(false) .repeatable(false) .argument("") .binding("pid")); Poco::Util::ServerApplication::defineOptions(new_options); } void BaseDaemon::handleSignal(int signal_id) { if (signal_id == SIGINT || signal_id == SIGQUIT || signal_id == SIGTERM) { std::unique_lock lock(signal_handler_mutex); { ++terminate_signals_counter; sigint_signals_counter += signal_id == SIGINT; signal_event.notify_all(); } onInterruptSignals(signal_id); } else throw DB::Exception(std::string("Unsupported signal: ") + msan_strsignal(signal_id), 0); } void BaseDaemon::onInterruptSignals(int signal_id) { is_cancelled = true; LOG_INFO(&logger(), "Received termination signal ({})", msan_strsignal(signal_id)); if (sigint_signals_counter >= 2) { LOG_INFO(&logger(), "Received second signal Interrupt. Immediately terminate."); kill(); } } void BaseDaemon::waitForTerminationRequest() { std::unique_lock lock(signal_handler_mutex); signal_event.wait(lock, [this](){ return terminate_signals_counter > 0; }); }