icinga2/lib/base/application.cpp

365 lines
8.9 KiB
C++

/******************************************************************************
* Icinga 2 *
* Copyright (C) 2012 Icinga Development Team (http://www.icinga.org/) *
* *
* This program is free software; you can redistribute it and/or *
* modify it under the terms of the GNU General Public License *
* as published by the Free Software Foundation; either version 2 *
* of the License, or (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program; if not, write to the Free Software Foundation *
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. *
******************************************************************************/
#include "i2-base.h"
#ifndef _WIN32
# include <ltdl.h>
#endif /* _WIN32 */
using namespace icinga;
Application *Application::m_Instance = NULL;
bool Application::m_ShuttingDown = false;
bool Application::m_Debugging = false;
boost::thread::id Application::m_MainThreadID;
/**
* Constructor for the Application class.
*/
Application::Application(const Dictionary::Ptr& serializedUpdate)
: DynamicObject(serializedUpdate), m_PidFile(NULL)
{
if (!IsLocal())
throw_exception(runtime_error("Application objects must be local."));
#ifdef _WIN32
/* disable GUI-based error messages for LoadLibrary() */
SetErrorMode(SEM_FAILCRITICALERRORS);
WSADATA wsaData;
if (WSAStartup(MAKEWORD(1, 1), &wsaData) != 0)
throw_exception(Win32Exception("WSAStartup failed", WSAGetLastError()));
#endif /* _WIN32 */
char *debugging = getenv("_DEBUG");
m_Debugging = (debugging && strtol(debugging, NULL, 10) != 0);
#ifdef _WIN32
if (IsDebuggerPresent())
m_Debugging = true;
#endif /* _WIN32 */
assert(m_Instance == NULL);
m_Instance = this;
}
/**
* Destructor for the application class.
*/
Application::~Application(void)
{
m_Instance = NULL;
m_ShuttingDown = true;
#ifdef _WIN32
WSACleanup();
#endif /* _WIN32 */
ClosePidFile();
}
/**
* Retrieves a pointer to the application singleton object.
*
* @returns The application object.
*/
Application::Ptr Application::GetInstance(void)
{
if (m_Instance)
return m_Instance->GetSelf();
else
return Application::Ptr();
}
/**
* Processes events for registered sockets and timers and calls whatever
* handlers have been set up for these events.
*/
void Application::RunEventLoop(void)
{
#ifdef _DEBUG
double nextProfile = 0;
#endif /* _DEBUG */
while (!m_ShuttingDown) {
Object::ClearHeldObjects();
double sleep = Timer::ProcessTimers();
if (m_ShuttingDown)
break;
Event::ProcessEvents(boost::get_system_time() + boost::posix_time::milliseconds(sleep * 1000));
DynamicObject::FinishTx();
DynamicObject::BeginTx();
#ifdef _DEBUG
if (nextProfile < Utility::GetTime()) {
stringstream msgbuf;
msgbuf << "Active objects: " << Object::GetAliveObjects();
Logger::Write(LogInformation, "base", msgbuf.str());
Object::PrintMemoryProfile();
nextProfile = Utility::GetTime() + 15.0;
}
#endif /* _DEBUG */
}
}
/**
* Signals the application to shut down during the next
* execution of the event loop.
*/
void Application::Shutdown(void)
{
m_ShuttingDown = true;
}
/**
* Retrieves the full path of the executable.
*
* @param argv0 The first command-line argument.
* @returns The path.
*/
String Application::GetExePath(const String& argv0)
{
String executablePath;
#ifndef _WIN32
char buffer[MAXPATHLEN];
if (getcwd(buffer, sizeof(buffer)) == NULL)
throw_exception(PosixException("getcwd failed", errno));
String workingDirectory = buffer;
if (argv0[0] != '/')
executablePath = workingDirectory + "/" + argv0;
else
executablePath = argv0;
bool foundSlash = false;
for (size_t i = 0; i < argv0.GetLength(); i++) {
if (argv0[i] == '/') {
foundSlash = true;
break;
}
}
if (!foundSlash) {
const char *pathEnv = getenv("PATH");
if (pathEnv != NULL) {
vector<String> paths;
boost::algorithm::split(paths, pathEnv, boost::is_any_of(":"));
bool foundPath = false;
BOOST_FOREACH(String& path, paths) {
String pathTest = path + "/" + argv0;
if (access(pathTest.CStr(), X_OK) == 0) {
executablePath = pathTest;
foundPath = true;
break;
}
}
if (!foundPath) {
executablePath.Clear();
throw_exception(runtime_error("Could not determine executable path."));
}
}
}
if (realpath(executablePath.CStr(), buffer) == NULL)
throw_exception(PosixException("realpath failed", errno));
return buffer;
#else /* _WIN32 */
char FullExePath[MAXPATHLEN];
if (!GetModuleFileName(NULL, FullExePath, sizeof(FullExePath)))
throw_exception(Win32Exception("GetModuleFileName() failed", GetLastError()));
return FullExePath;
#endif /* _WIN32 */
}
/**
* Retrieves the debugging mode of the application.
*
* @returns true if the application is being debugged, false otherwise
*/
bool Application::IsDebugging(void)
{
return m_Debugging;
}
/**
* Checks whether we're currently on the main thread.
*
* @returns true if this is the main thread, false otherwise
*/
bool Application::IsMainThread(void)
{
return (boost::this_thread::get_id() == m_MainThreadID);
}
/**
* Sets the main thread to the currently running thread.
*/
void Application::SetMainThread(void)
{
m_MainThreadID = boost::this_thread::get_id();
}
#ifndef _WIN32
/**
* Signal handler for SIGINT. Prepares the application for cleanly
* shutting down during the next execution of the event loop.
*
* @param signum The signal number.
*/
void Application::SigIntHandler(int signum)
{
assert(signum == SIGINT);
Application::Ptr instance = Application::GetInstance();
if (!instance)
return;
instance->Shutdown();
struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.sa_handler = SIG_DFL;
sigaction(SIGINT, &sa, NULL);
}
#else /* _WIN32 */
/**
* Console control handler. Prepares the application for cleanly
* shutting down during the next execution of the event loop.
*/
BOOL WINAPI Application::CtrlHandler(DWORD type)
{
Application::Ptr instance = Application::GetInstance();
if (!instance)
return TRUE;
instance->GetInstance()->Shutdown();
SetConsoleCtrlHandler(NULL, FALSE);
return TRUE;
}
#endif /* _WIN32 */
/**
* Runs the application.
*
* @param argc The number of arguments.
* @param argv The arguments that should be passed to the application.
* @returns The application's exit code.
*/
int Application::Run(int argc, char **argv)
{
int result;
#ifndef _WIN32
struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.sa_handler = &Application::SigIntHandler;
sigaction(SIGINT, &sa, NULL);
sa.sa_handler = SIG_IGN;
sigaction(SIGPIPE, &sa, NULL);
#else
SetConsoleCtrlHandler(&Application::CtrlHandler, TRUE);
#endif /* _WIN32 */
m_Arguments.clear();
for (int i = 0; i < argc; i++)
m_Arguments.push_back(String(argv[i]));
DynamicObject::BeginTx();
if (IsDebugging()) {
result = Main(m_Arguments);
} else {
try {
result = Main(m_Arguments);
} catch (const exception& ex) {
Logger::Write(LogCritical, "base", "---");
Logger::Write(LogCritical, "base", "Exception: " + Utility::GetTypeName(typeid(ex)));
Logger::Write(LogCritical, "base", "Message: " + String(ex.what()));
result = EXIT_FAILURE;
}
}
DynamicObject::FinishTx();
DynamicObject::DeactivateObjects();
return result;
}
/**
* Grabs the PID file lock and updates the PID.
*
* @param filename The name of the PID file.
*/
void Application::UpdatePidFile(const String& filename)
{
ClosePidFile();
/* There's just no sane way of getting a file descriptor for a
* C++ ofstream which is why we're using FILEs here. */
m_PidFile = fopen(filename.CStr(), "w");
if (m_PidFile == NULL)
throw_exception(runtime_error("Could not open PID file '" + filename + "'"));
#ifndef _WIN32
if (flock(fileno(m_PidFile), LOCK_EX | LOCK_NB) < 0) {
ClosePidFile();
throw_exception(runtime_error("Another instance of the application is "
"already running. Remove the '" + filename + "' file if "
"you're certain that this is not the case."));
}
#endif /* _WIN32 */
fprintf(m_PidFile, "%d", Utility::GetPid());
fflush(m_PidFile);
}
/**
* Closes the PID file. Does nothing if the PID file is not currently open.
*/
void Application::ClosePidFile(void)
{
if (m_PidFile != NULL)
fclose(m_PidFile);
m_PidFile = NULL;
}