icinga2/lib/cli/daemoncommand.cpp

820 lines
22 KiB
C++

/* Icinga 2 | (c) 2012 Icinga GmbH | GPLv2+ */
#include "cli/daemoncommand.hpp"
#include "cli/daemonutility.hpp"
#include "remote/apilistener.hpp"
#include "remote/configobjectutility.hpp"
#include "config/configcompiler.hpp"
#include "config/configcompilercontext.hpp"
#include "config/configitembuilder.hpp"
#include "base/atomic.hpp"
#include "base/defer.hpp"
#include "base/logger.hpp"
#include "base/application.hpp"
#include "base/timer.hpp"
#include "base/utility.hpp"
#include "base/exception.hpp"
#include "base/convert.hpp"
#include "base/scriptglobal.hpp"
#include "base/context.hpp"
#include "config.h"
#include <cstdint>
#include <cstring>
#include <boost/program_options.hpp>
#include <iostream>
#include <fstream>
#ifdef _WIN32
#include <windows.h>
#else /* _WIN32 */
#include <signal.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#endif /* _WIN32 */
#ifdef HAVE_SYSTEMD
#include <systemd/sd-daemon.h>
#endif /* HAVE_SYSTEMD */
using namespace icinga;
namespace po = boost::program_options;
static po::variables_map g_AppParams;
REGISTER_CLICOMMAND("daemon", DaemonCommand);
/*
* Daemonize(). On error, this function logs by itself and exits (i.e. does not return).
*
* Implementation note: We're only supposed to call exit() in one of the forked processes.
* The other process calls _exit(). This prevents issues with exit handlers like atexit().
*/
static void Daemonize() noexcept
{
#ifndef _WIN32
try {
Application::UninitializeBase();
} catch (const std::exception& ex) {
Log(LogCritical, "cli")
<< "Failed to stop thread pool before daemonizing, unexpected error: " << DiagnosticInformation(ex);
exit(EXIT_FAILURE);
}
pid_t pid = fork();
if (pid == -1) {
Log(LogCritical, "cli")
<< "fork() failed with error code " << errno << ", \"" << Utility::FormatErrorNumber(errno) << "\"";
exit(EXIT_FAILURE);
}
if (pid) {
// systemd requires that the pidfile of the daemon is written before the forking
// process terminates. So wait till either the forked daemon has written a pidfile or died.
int status;
int ret;
pid_t readpid;
do {
Utility::Sleep(0.1);
readpid = Application::ReadPidFile(Configuration::PidPath);
ret = waitpid(pid, &status, WNOHANG);
} while (readpid != pid && ret == 0);
if (ret == pid) {
Log(LogCritical, "cli", "The daemon could not be started. See log output for details.");
_exit(EXIT_FAILURE);
} else if (ret == -1) {
Log(LogCritical, "cli")
<< "waitpid() failed with error code " << errno << ", \"" << Utility::FormatErrorNumber(errno) << "\"";
_exit(EXIT_FAILURE);
}
_exit(EXIT_SUCCESS);
}
Log(LogDebug, "Daemonize()")
<< "Child process with PID " << Utility::GetPid() << " continues; re-initializing base.";
// Detach from controlling terminal
pid_t sid = setsid();
if (sid == -1) {
Log(LogCritical, "cli")
<< "setsid() failed with error code " << errno << ", \"" << Utility::FormatErrorNumber(errno) << "\"";
exit(EXIT_FAILURE);
}
try {
Application::InitializeBase();
} catch (const std::exception& ex) {
Log(LogCritical, "cli")
<< "Failed to re-initialize thread pool after daemonizing: " << DiagnosticInformation(ex);
exit(EXIT_FAILURE);
}
#endif /* _WIN32 */
}
static void CloseStdIO(const String& stderrFile)
{
#ifndef _WIN32
int fdnull = open("/dev/null", O_RDWR);
if (fdnull >= 0) {
if (fdnull != 0)
dup2(fdnull, 0);
if (fdnull != 1)
dup2(fdnull, 1);
if (fdnull > 1)
close(fdnull);
}
const char *errPath = "/dev/null";
if (!stderrFile.IsEmpty())
errPath = stderrFile.CStr();
int fderr = open(errPath, O_WRONLY | O_APPEND);
if (fderr < 0 && errno == ENOENT)
fderr = open(errPath, O_CREAT | O_WRONLY | O_APPEND, 0600);
if (fderr >= 0) {
if (fderr != 2)
dup2(fderr, 2);
if (fderr > 2)
close(fderr);
}
#endif
}
String DaemonCommand::GetDescription() const
{
return "Starts Icinga 2.";
}
String DaemonCommand::GetShortDescription() const
{
return "starts Icinga 2";
}
void DaemonCommand::InitParameters(boost::program_options::options_description& visibleDesc,
boost::program_options::options_description& hiddenDesc) const
{
visibleDesc.add_options()
("config,c", po::value<std::vector<std::string> >(), "parse a configuration file")
("no-config,z", "start without a configuration file")
("validate,C", "exit after validating the configuration")
("errorlog,e", po::value<std::string>(), "log fatal errors to the specified log file (only works in combination with --daemonize or --close-stdio)")
#ifndef _WIN32
("daemonize,d", "detach from the controlling terminal")
("close-stdio", "do not log to stdout (or stderr) after startup")
#endif /* _WIN32 */
;
}
std::vector<String> DaemonCommand::GetArgumentSuggestions(const String& argument, const String& word) const
{
if (argument == "config" || argument == "errorlog")
return GetBashCompletionSuggestions("file", word);
else
return CLICommand::GetArgumentSuggestions(argument, word);
}
#ifndef _WIN32
// The PID of the Icinga umbrella process
pid_t l_UmbrellaPid = 0;
// Whether the umbrella process allowed us to continue working beyond config validation
static Atomic<bool> l_AllowedToWork (false);
#endif /* _WIN32 */
#ifdef I2_DEBUG
/**
* Determine whether the developer wants to delay the worker process to attach a debugger to it.
*
* @return Internal.DebugWorkerDelay double
*/
static double GetDebugWorkerDelay()
{
Namespace::Ptr internal = ScriptGlobal::Get("Internal", &Empty);
Value vdebug;
if (internal && internal->Get("DebugWorkerDelay", &vdebug))
return Convert::ToDouble(vdebug);
return 0.0;
}
#endif /* I2_DEBUG */
/**
* Do the actual work (config loading, ...)
*
* @param configs Files to read config from
* @param closeConsoleLog Whether to close the console log after config loading
* @param stderrFile Where to log errors
*
* @return Exit code
*/
static inline
int RunWorker(const std::vector<std::string>& configs, bool closeConsoleLog = false, const String& stderrFile = String())
{
#ifdef I2_DEBUG
double delay = GetDebugWorkerDelay();
if (delay > 0.0) {
Log(LogInformation, "RunWorker")
<< "DEBUG: Current PID: " << Utility::GetPid() << ". Sleeping for " << delay << " seconds to allow lldb/gdb -p <PID> attachment.";
Utility::Sleep(delay);
}
#endif /* I2_DEBUG */
Log(LogInformation, "cli", "Loading configuration file(s).");
{
std::vector<ConfigItem::Ptr> newItems;
if (!DaemonUtility::LoadConfigFiles(configs, newItems, Configuration::ObjectsPath, Configuration::VarsPath)) {
Log(LogCritical, "cli", "Config validation failed. Re-run with 'icinga2 daemon -C' after fixing the config.");
return EXIT_FAILURE;
}
#ifndef _WIN32
Log(LogNotice, "cli")
<< "Notifying umbrella process (PID " << l_UmbrellaPid << ") about the config loading success";
(void)kill(l_UmbrellaPid, SIGUSR2);
Log(LogNotice, "cli")
<< "Waiting for the umbrella process to let us doing the actual work";
if (closeConsoleLog) {
CloseStdIO(stderrFile);
Logger::DisableConsoleLog();
}
while (!l_AllowedToWork.load()) {
Utility::Sleep(0.2);
}
Log(LogNotice, "cli")
<< "The umbrella process let us continuing";
#endif /* _WIN32 */
/* restore the previous program state */
try {
ConfigObject::RestoreObjects(Configuration::StatePath);
} catch (const std::exception& ex) {
Log(LogCritical, "cli")
<< "Failed to restore state file: " << DiagnosticInformation(ex);
return EXIT_FAILURE;
}
WorkQueue upq(25000, Configuration::Concurrency);
upq.SetName("DaemonCommand::Run");
// activate config only after daemonization: it starts threads and that is not compatible with fork()
if (!ConfigItem::ActivateItems(upq, newItems, false, false, true)) {
Log(LogCritical, "cli", "Error activating configuration.");
return EXIT_FAILURE;
}
}
/* Create the internal API object storage. Do this here too with setups without API. */
ConfigObjectUtility::CreateStorage();
/* Remove ignored Downtime/Comment objects. */
try {
String configDir = ConfigObjectUtility::GetConfigDir();
ConfigItem::RemoveIgnoredItems(configDir);
} catch (const std::exception& ex) {
Log(LogNotice, "cli")
<< "Cannot clean ignored downtimes/comments: " << ex.what();
}
ApiListener::UpdateObjectAuthority();
return Application::GetInstance()->Run();
}
#ifndef _WIN32
/**
* The possible states of a seemless worker being started by StartUnixWorker().
*/
enum class UnixWorkerState : uint_fast8_t
{
Pending,
LoadedConfig,
Failed
};
// The signals to block temporarily in StartUnixWorker().
static const sigset_t l_UnixWorkerSignals = ([]() -> sigset_t {
sigset_t s;
(void)sigemptyset(&s);
(void)sigaddset(&s, SIGCHLD);
(void)sigaddset(&s, SIGUSR1);
(void)sigaddset(&s, SIGUSR2);
(void)sigaddset(&s, SIGINT);
(void)sigaddset(&s, SIGTERM);
(void)sigaddset(&s, SIGHUP);
return s;
})();
// The PID of the seemless worker currently being started by StartUnixWorker()
static Atomic<pid_t> l_CurrentlyStartingUnixWorkerPid (-1);
// The state of the seemless worker currently being started by StartUnixWorker()
static Atomic<UnixWorkerState> l_CurrentlyStartingUnixWorkerState (UnixWorkerState::Pending);
// The last temination signal we received
static Atomic<int> l_TermSignal (-1);
// Whether someone requested to re-load config (and we didn't handle that request, yet)
static Atomic<bool> l_RequestedReload (false);
// Whether someone requested to re-open logs (and we didn't handle that request, yet)
static Atomic<bool> l_RequestedReopenLogs (false);
/**
* Umbrella process' signal handlers
*/
static void UmbrellaSignalHandler(int num, siginfo_t *info, void*)
{
switch (num) {
case SIGUSR1:
// Someone requested to re-open logs
l_RequestedReopenLogs.store(true);
break;
case SIGUSR2:
if (l_CurrentlyStartingUnixWorkerState.load() == UnixWorkerState::Pending
&& (info->si_pid == 0 || info->si_pid == l_CurrentlyStartingUnixWorkerPid.load()) ) {
// The seemless worker currently being started by StartUnixWorker() successfully loaded its config
l_CurrentlyStartingUnixWorkerState.store(UnixWorkerState::LoadedConfig);
}
break;
case SIGCHLD:
if (l_CurrentlyStartingUnixWorkerState.load() == UnixWorkerState::Pending
&& (info->si_pid == 0 || info->si_pid == l_CurrentlyStartingUnixWorkerPid.load()) ) {
// The seemless worker currently being started by StartUnixWorker() failed
l_CurrentlyStartingUnixWorkerState.store(UnixWorkerState::Failed);
}
break;
case SIGINT:
case SIGTERM:
// Someone requested our termination
{
struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.sa_handler = SIG_DFL;
(void)sigaction(num, &sa, nullptr);
}
l_TermSignal.store(num);
break;
case SIGHUP:
// Someone requested to re-load config
l_RequestedReload.store(true);
break;
default:
// Programming error (or someone has broken the userspace)
VERIFY(!"Caught unexpected signal");
}
}
/**
* Seemless worker's signal handlers
*/
static void WorkerSignalHandler(int num, siginfo_t *info, void*)
{
switch (num) {
case SIGUSR2:
if (info->si_pid == 0 || info->si_pid == l_UmbrellaPid) {
// The umbrella process allowed us to continue working beyond config validation
l_AllowedToWork.store(true);
}
break;
case SIGINT:
case SIGTERM:
if (info->si_pid == 0 || info->si_pid == l_UmbrellaPid) {
// The umbrella process requested our termination
Application::RequestShutdown();
}
break;
default:
// Programming error (or someone has broken the userspace)
VERIFY(!"Caught unexpected signal");
}
}
#ifdef HAVE_SYSTEMD
// When we last notified the watchdog.
static Atomic<double> l_LastNotifiedWatchdog (0);
/**
* Notify the watchdog if not notified during the last 2.5s.
*/
static void NotifyWatchdog()
{
double now = Utility::GetTime();
if (now - l_LastNotifiedWatchdog.load() >= 2.5) {
sd_notify(0, "WATCHDOG=1");
l_LastNotifiedWatchdog.store(now);
}
}
#endif /* HAVE_SYSTEMD */
/**
* Starts seemless worker process doing the actual work (config loading, ...)
*
* @param configs Files to read config from
* @param closeConsoleLog Whether to close the console log after config loading
* @param stderrFile Where to log errors
*
* @return The worker's PID on success, -1 on failure (if the worker couldn't load its config)
*/
static pid_t StartUnixWorker(const std::vector<std::string>& configs, bool closeConsoleLog = false, const String& stderrFile = String())
{
Log(LogNotice, "cli")
<< "Spawning seemless worker process doing the actual work";
try {
Application::UninitializeBase();
} catch (const std::exception& ex) {
Log(LogCritical, "cli")
<< "Failed to stop thread pool before forking, unexpected error: " << DiagnosticInformation(ex);
exit(EXIT_FAILURE);
}
/* Block the signal handlers we'd like to change in the child process until we changed them.
* Block SIGUSR2 and SIGCHLD handlers until we've set l_CurrentlyStartingUnixWorkerPid.
*/
(void)sigprocmask(SIG_BLOCK, &l_UnixWorkerSignals, nullptr);
pid_t pid = fork();
switch (pid) {
case -1:
Log(LogCritical, "cli")
<< "fork() failed with error code " << errno << ", \"" << Utility::FormatErrorNumber(errno) << "\"";
exit(EXIT_FAILURE);
case 0:
try {
{
struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.sa_handler = SIG_DFL;
(void)sigaction(SIGCHLD, &sa, nullptr);
(void)sigaction(SIGUSR1, &sa, nullptr);
(void)sigaction(SIGHUP, &sa, nullptr);
}
{
struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.sa_sigaction = &WorkerSignalHandler;
sa.sa_flags = SA_RESTART | SA_SIGINFO;
(void)sigaction(SIGUSR2, &sa, nullptr);
(void)sigaction(SIGINT, &sa, nullptr);
(void)sigaction(SIGTERM, &sa, nullptr);
}
(void)sigprocmask(SIG_UNBLOCK, &l_UnixWorkerSignals, nullptr);
try {
Application::InitializeBase();
} catch (const std::exception& ex) {
Log(LogCritical, "cli")
<< "Failed to re-initialize thread pool after forking (child): " << DiagnosticInformation(ex);
_exit(EXIT_FAILURE);
}
_exit(RunWorker(configs, closeConsoleLog, stderrFile));
} catch (...) {
_exit(EXIT_FAILURE);
}
default:
l_CurrentlyStartingUnixWorkerPid.store(pid);
(void)sigprocmask(SIG_UNBLOCK, &l_UnixWorkerSignals, nullptr);
Log(LogNotice, "cli")
<< "Spawned worker process (PID " << pid << "), waiting for it to load its config";
// Wait for the newly spawned process to either load its config or fail.
for (;;) {
#ifdef HAVE_SYSTEMD
NotifyWatchdog();
#endif /* HAVE_SYSTEMD */
switch (l_CurrentlyStartingUnixWorkerState.load()) {
case UnixWorkerState::LoadedConfig:
Log(LogNotice, "cli")
<< "Worker process successfully loaded its config";
break;
case UnixWorkerState::Failed:
Log(LogNotice, "cli")
<< "Worker process couldn't load its config";
while (waitpid(pid, nullptr, 0) == -1 && errno == EINTR) {
#ifdef HAVE_SYSTEMD
NotifyWatchdog();
#endif /* HAVE_SYSTEMD */
}
pid = -1;
break;
default:
Utility::Sleep(0.2);
continue;
}
break;
}
// Reset flags for the next time
l_CurrentlyStartingUnixWorkerPid.store(-1);
l_CurrentlyStartingUnixWorkerState.store(UnixWorkerState::Pending);
try {
Application::InitializeBase();
} catch (const std::exception& ex) {
Log(LogCritical, "cli")
<< "Failed to re-initialize thread pool after forking (parent): " << DiagnosticInformation(ex);
exit(EXIT_FAILURE);
}
}
return pid;
}
/**
* Workaround to instantiate Application (which is abstract) in DaemonCommand#Run()
*/
class PidFileManagementApp : public Application
{
public:
inline int Main() override
{
return EXIT_FAILURE;
}
};
#endif /* _WIN32 */
/**
* The entry point for the "daemon" CLI command.
*
* @returns An exit status.
*/
int DaemonCommand::Run(const po::variables_map& vm, const std::vector<std::string>& ap) const
{
#ifdef _WIN32
SetConsoleOutputCP(65001);
#endif /* _WIN32 */
Logger::EnableTimestamp();
Log(LogInformation, "cli")
<< "Icinga application loader (version: " << Application::GetAppVersion()
#ifdef I2_DEBUG
<< "; debug"
#endif /* I2_DEBUG */
<< ")";
std::vector<std::string> configs;
if (vm.count("config") > 0)
configs = vm["config"].as<std::vector<std::string> >();
else if (!vm.count("no-config")) {
/* The implicit string assignment is needed for Windows builds. */
String configDir = Configuration::ConfigDir;
configs.push_back(configDir + "/icinga2.conf");
}
if (vm.count("validate")) {
Log(LogInformation, "cli", "Loading configuration file(s).");
std::vector<ConfigItem::Ptr> newItems;
if (!DaemonUtility::LoadConfigFiles(configs, newItems, Configuration::ObjectsPath, Configuration::VarsPath)) {
Log(LogCritical, "cli", "Config validation failed. Re-run with 'icinga2 daemon -C' after fixing the config.");
return EXIT_FAILURE;
}
Log(LogInformation, "cli", "Finished validating the configuration file(s).");
return EXIT_SUCCESS;
}
{
pid_t runningpid = Application::ReadPidFile(Configuration::PidPath);
if (runningpid > 0) {
Log(LogCritical, "cli")
<< "Another instance of Icinga already running with PID " << runningpid;
return EXIT_FAILURE;
}
}
if (vm.count("daemonize")) {
// this subroutine either succeeds, or logs an error
// and terminates the process (does not return).
Daemonize();
}
#ifndef _WIN32
/* The Application manages the PID file,
* but on *nix this process doesn't load any config
* so there's no central Application instance.
*/
PidFileManagementApp app;
try {
app.UpdatePidFile(Configuration::PidPath);
} catch (const std::exception&) {
Log(LogCritical, "Application")
<< "Cannot update PID file '" << Configuration::PidPath << "'. Aborting.";
return EXIT_FAILURE;
}
Defer closePidFile ([&app]() {
app.ClosePidFile(true);
});
#endif /* _WIN32 */
if (vm.count("daemonize")) {
// After disabling the console log, any further errors will go to the configured log only.
// Let's try to make this clear and say good bye.
Log(LogInformation, "cli", "Closing console log.");
String errorLog;
if (vm.count("errorlog"))
errorLog = vm["errorlog"].as<std::string>();
CloseStdIO(errorLog);
Logger::DisableConsoleLog();
}
#ifdef _WIN32
return RunWorker(configs);
#else /* _WIN32 */
l_UmbrellaPid = getpid();
Application::SetUmbrellaProcess(l_UmbrellaPid);
{
struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.sa_sigaction = &UmbrellaSignalHandler;
sa.sa_flags = SA_NOCLDSTOP | SA_RESTART | SA_SIGINFO;
(void)sigaction(SIGCHLD, &sa, nullptr);
(void)sigaction(SIGUSR1, &sa, nullptr);
(void)sigaction(SIGUSR2, &sa, nullptr);
(void)sigaction(SIGINT, &sa, nullptr);
(void)sigaction(SIGTERM, &sa, nullptr);
(void)sigaction(SIGHUP, &sa, nullptr);
}
bool closeConsoleLog = !vm.count("daemonize") && vm.count("close-stdio");
String errorLog;
if (vm.count("errorlog"))
errorLog = vm["errorlog"].as<std::string>();
// The PID of the current seemless worker
pid_t currentWorker = StartUnixWorker(configs, closeConsoleLog, errorLog);
if (currentWorker == -1) {
return EXIT_FAILURE;
}
if (closeConsoleLog) {
// After disabling the console log, any further errors will go to the configured log only.
// Let's try to make this clear and say good bye.
Log(LogInformation, "cli", "Closing console log.");
CloseStdIO(errorLog);
Logger::DisableConsoleLog();
}
// Immediately allow the first (non-reload) worker to continue working beyond config validation
(void)kill(currentWorker, SIGUSR2);
#ifdef HAVE_SYSTEMD
sd_notify(0, "READY=1");
#endif /* HAVE_SYSTEMD */
// Whether we already forwarded a termination signal to the seemless worker
bool requestedTermination = false;
// Whether we already notified systemd about our termination
bool notifiedTermination = false;
for (;;) {
#ifdef HAVE_SYSTEMD
NotifyWatchdog();
#endif /* HAVE_SYSTEMD */
if (!requestedTermination) {
int termSig = l_TermSignal.load();
if (termSig != -1) {
Log(LogNotice, "cli")
<< "Got signal " << termSig << ", forwarding to seemless worker (PID " << currentWorker << ")";
(void)kill(currentWorker, termSig);
requestedTermination = true;
#ifdef HAVE_SYSTEMD
if (!notifiedTermination) {
notifiedTermination = true;
sd_notify(0, "STOPPING=1");
}
#endif /* HAVE_SYSTEMD */
}
}
if (l_RequestedReload.exchange(false)) {
Log(LogInformation, "Application")
<< "Got reload command: Starting new instance.";
#ifdef HAVE_SYSTEMD
sd_notify(0, "RELOADING=1");
#endif /* HAVE_SYSTEMD */
pid_t nextWorker = StartUnixWorker(configs);
if (nextWorker == -1) {
Log(LogCritical, "Application", "Found error in config: reloading aborted");
} else {
Log(LogInformation, "Application")
<< "Reload done, old process shutting down. Child process with PID '" << nextWorker << "' is taking over.";
(void)kill(currentWorker, SIGTERM);
{
double start = Utility::GetTime();
while (waitpid(currentWorker, nullptr, 0) == -1 && errno == EINTR) {
#ifdef HAVE_SYSTEMD
NotifyWatchdog();
#endif /* HAVE_SYSTEMD */
}
Log(LogNotice, "cli")
<< "Waited for " << Utility::FormatDuration(Utility::GetTime() - start) << " on old process to exit.";
}
// Old instance shut down, allow the new one to continue working beyond config validation
(void)kill(nextWorker, SIGUSR2);
currentWorker = nextWorker;
}
#ifdef HAVE_SYSTEMD
sd_notify(0, "READY=1");
#endif /* HAVE_SYSTEMD */
}
if (l_RequestedReopenLogs.exchange(false)) {
Log(LogNotice, "cli")
<< "Got signal " << SIGUSR1 << ", forwarding to seemless worker (PID " << currentWorker << ")";
(void)kill(currentWorker, SIGUSR1);
}
{
int status;
if (waitpid(currentWorker, &status, WNOHANG) > 0) {
Log(LogNotice, "cli")
<< "Seemless worker (PID " << currentWorker << ") stopped, stopping as well";
#ifdef HAVE_SYSTEMD
if (!notifiedTermination) {
notifiedTermination = true;
sd_notify(0, "STOPPING=1");
}
#endif /* HAVE_SYSTEMD */
// If killed by signal, forward it via the exit code (to be as seemless as possible)
return WIFSIGNALED(status) ? 128 + WTERMSIG(status) : WEXITSTATUS(status);
}
}
Utility::Sleep(0.2);
}
#endif /* _WIN32 */
}