JUCE/modules/juce_events/messages/juce_ApplicationBase.cpp

/*
  ==============================================================================

   This file is part of the JUCE library.
   Copyright (c) 2016 - ROLI Ltd.

   Permission is granted to use this software under the terms of the ISC license
   http://www.isc.org/downloads/software-support-policy/isc-license/

   Permission to use, copy, modify, and/or distribute this software for any
   purpose with or without fee is hereby granted, provided that the above
   copyright notice and this permission notice appear in all copies.

   THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH REGARD
   TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
   FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT,
   OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
   USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
   TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
   OF THIS SOFTWARE.

   -----------------------------------------------------------------------------

   To release a closed-source product which uses other parts of JUCE not
   licensed under the ISC terms, commercial licenses are available: visit
   www.juce.com for more information.

  ==============================================================================
*/

JUCEApplicationBase::CreateInstanceFunction JUCEApplicationBase::createInstance = 0;
JUCEApplicationBase* JUCEApplicationBase::appInstance = nullptr;

JUCEApplicationBase::JUCEApplicationBase()
    : appReturnValue (0),
      stillInitialising (true)
{
    jassert (isStandaloneApp() && appInstance == nullptr);
    appInstance = this;
}

JUCEApplicationBase::~JUCEApplicationBase()
{
    jassert (appInstance == this);
    appInstance = nullptr;
}

void JUCEApplicationBase::setApplicationReturnValue (const int newReturnValue) noexcept
{
    appReturnValue = newReturnValue;
}

// This is called on the Mac and iOS where the OS doesn't allow the stack to unwind on shutdown..
void JUCEApplicationBase::appWillTerminateByForce()
{
    JUCE_AUTORELEASEPOOL
    {
        {
            const ScopedPointer<JUCEApplicationBase> app (appInstance);

            if (app != nullptr)
                app->shutdownApp();
        }

        DeletedAtShutdown::deleteAll();
        MessageManager::deleteInstance();
    }
}

void JUCEApplicationBase::quit()
{
    MessageManager::getInstance()->stopDispatchLoop();
}

void JUCEApplicationBase::sendUnhandledException (const std::exception* const e,
                                                  const char* const sourceFile,
                                                  const int lineNumber)
{
    if (JUCEApplicationBase* const app = JUCEApplicationBase::getInstance())
        app->unhandledException (e, sourceFile, lineNumber);
}

//==============================================================================
#if ! (JUCE_IOS || JUCE_ANDROID)
 #define JUCE_HANDLE_MULTIPLE_INSTANCES 1
#endif

#if JUCE_HANDLE_MULTIPLE_INSTANCES
struct JUCEApplicationBase::MultipleInstanceHandler  : public ActionListener
{
public:
    MultipleInstanceHandler (const String& appName)
        : appLock ("juceAppLock_" + appName)
    {
    }

    bool sendCommandLineToPreexistingInstance()
    {
        if (appLock.enter (0))
            return false;

        JUCEApplicationBase* const app = JUCEApplicationBase::getInstance();
        jassert (app != nullptr);

        MessageManager::broadcastMessage (app->getApplicationName()
                                            + "/" + app->getCommandLineParameters());
        return true;
    }

    void actionListenerCallback (const String& message) override
    {
        if (JUCEApplicationBase* const app = JUCEApplicationBase::getInstance())
        {
            const String appName (app->getApplicationName());

            if (message.startsWith (appName + "/"))
                app->anotherInstanceStarted (message.substring (appName.length() + 1));
        }
    }

private:
    InterProcessLock appLock;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (MultipleInstanceHandler)
};

bool JUCEApplicationBase::sendCommandLineToPreexistingInstance()
{
    jassert (multipleInstanceHandler == nullptr); // this must only be called once!

    multipleInstanceHandler = new MultipleInstanceHandler (getApplicationName());
    return multipleInstanceHandler->sendCommandLineToPreexistingInstance();
}

#else
struct JUCEApplicationBase::MultipleInstanceHandler {};
#endif

//==============================================================================
#if JUCE_ANDROID

StringArray JUCEApplicationBase::getCommandLineParameterArray() { return {}; }
String JUCEApplicationBase::getCommandLineParameters()          { return {}; }

#else

#if JUCE_WINDOWS && ! defined (_CONSOLE)

String JUCE_CALLTYPE JUCEApplicationBase::getCommandLineParameters()
{
    return CharacterFunctions::findEndOfToken (CharPointer_UTF16 (GetCommandLineW()),
                                               CharPointer_UTF16 (L" "),
                                               CharPointer_UTF16 (L"\"")).findEndOfWhitespace();
}

StringArray JUCE_CALLTYPE JUCEApplicationBase::getCommandLineParameterArray()
{
    StringArray s;

    int argc = 0;
    if (LPWSTR* const argv = CommandLineToArgvW (GetCommandLineW(), &argc))
    {
        s = StringArray (argv + 1, argc - 1);
        LocalFree (argv);
    }

    return s;
}

#else

#if JUCE_IOS
 extern int juce_iOSMain (int argc, const char* argv[], void* classPtr);
#endif

#if JUCE_MAC
 extern void initialiseNSApplication();
#endif

#if JUCE_LINUX && JUCE_MODULE_AVAILABLE_juce_gui_extra
 extern int juce_gtkWebkitMain (int argc, const char* argv[]);
#endif

#if JUCE_WINDOWS
 const char* const* juce_argv = nullptr;
 int juce_argc = 0;
#else
 extern const char* const* juce_argv;  // declared in juce_core
 extern int juce_argc;
#endif

String JUCEApplicationBase::getCommandLineParameters()
{
    String argString;

    for (int i = 1; i < juce_argc; ++i)
    {
        String arg (juce_argv[i]);

        if (arg.containsChar (' ') && ! arg.isQuotedString())
            arg = arg.quoted ('"');

        argString << arg << ' ';
    }

    return argString.trim();
}

StringArray JUCEApplicationBase::getCommandLineParameterArray()
{
    return StringArray (juce_argv + 1, juce_argc - 1);
}

int JUCEApplicationBase::main (int argc, const char* argv[], void* customDelegate)
{
    JUCE_AUTORELEASEPOOL
    {
        juce_argc = argc;
        juce_argv = argv;

       #if JUCE_MAC
        initialiseNSApplication();
       #endif

       #if JUCE_LINUX && JUCE_MODULE_AVAILABLE_juce_gui_extra
        if (argc >= 2 && String (argv[1]) == "--juce-gtkwebkitfork-child")
            return juce_gtkWebkitMain (argc, argv);
       #endif

       #if JUCE_IOS
        return juce_iOSMain (argc, argv, customDelegate);
       #else
        ignoreUnused (customDelegate);

        return JUCEApplicationBase::main();
       #endif
    }
}

#endif

//==============================================================================
int JUCEApplicationBase::main()
{
    ScopedJuceInitialiser_GUI libraryInitialiser;
    jassert (createInstance != nullptr);

    const ScopedPointer<JUCEApplicationBase> app (createInstance());
    jassert (app != nullptr);

    if (! app->initialiseApp())
        return app->shutdownApp();

    JUCE_TRY
    {
        // loop until a quit message is received..
        MessageManager::getInstance()->runDispatchLoop();
    }
    JUCE_CATCH_EXCEPTION

    return app->shutdownApp();
}

#endif

//==============================================================================
bool JUCEApplicationBase::initialiseApp()
{
   #if JUCE_HANDLE_MULTIPLE_INSTANCES
    if ((! moreThanOneInstanceAllowed()) && sendCommandLineToPreexistingInstance())
    {
        DBG ("Another instance is running - quitting...");
        return false;
    }
   #endif

   #if JUCE_WINDOWS && JUCE_STANDALONE_APPLICATION && (! defined (_CONSOLE)) && (! JUCE_MINGW)
    if (AttachConsole (ATTACH_PARENT_PROCESS) != 0)
    {
        // if we've launched a GUI app from cmd.exe or PowerShell, we need this to enable printf etc.
        // However, only reassign stdout, stderr, stdin if they have not been already opened by
        // a redirect or similar.
        FILE* ignore;

        if (_fileno(stdout) < 0) freopen_s (&ignore, "CONOUT$", "w", stdout);
        if (_fileno(stderr) < 0) freopen_s (&ignore, "CONOUT$", "w", stderr);
        if (_fileno(stdin)  < 0) freopen_s (&ignore, "CONIN$",  "r", stdin);
    }
   #endif

    // let the app do its setting-up..
    initialise (getCommandLineParameters());

    stillInitialising = false;

    if (MessageManager::getInstance()->hasStopMessageBeenSent())
        return false;

   #if JUCE_HANDLE_MULTIPLE_INSTANCES
    if (multipleInstanceHandler != nullptr)
        MessageManager::getInstance()->registerBroadcastListener (multipleInstanceHandler);
   #endif

    return true;
}

int JUCEApplicationBase::shutdownApp()
{
    jassert (JUCEApplicationBase::getInstance() == this);

   #if JUCE_HANDLE_MULTIPLE_INSTANCES
    if (multipleInstanceHandler != nullptr)
        MessageManager::getInstance()->deregisterBroadcastListener (multipleInstanceHandler);
   #endif

    JUCE_TRY
    {
        // give the app a chance to clean up..
        shutdown();
    }
    JUCE_CATCH_EXCEPTION

    multipleInstanceHandler = nullptr;
    return getApplicationReturnValue();
}