juce_ApplicationBase.cpp

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/*
  ==============================================================================
 
   This file is part of the JUCE library.
   Copyright (c) 2022 - Raw Material Software Limited
 
   JUCE is an open source library subject to commercial or open-source
   licensing.
 
   The code included in this file is provided 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.
 
   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.
 
  ==============================================================================
*/
 
namespace juce
{
 
JUCEApplicationBase::CreateInstanceFunction JUCEApplicationBase::createInstance = nullptr;
JUCEApplicationBase* JUCEApplicationBase::appInstance = nullptr;
 
#if JUCE_IOS
void* JUCEApplicationBase::iOSCustomDelegate = nullptr;
#endif
 
JUCEApplicationBase::JUCEApplicationBase()
{
    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 std::unique_ptr<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 (auto* app = JUCEApplicationBase::getInstance())
    {
        // If you hit this assertion then the __FILE__ macro is providing a
        // relative path instead of an absolute path. On Windows this will be
        // a path relative to the build directory rather than the currently
        // running application. To fix this you must compile with the /FC flag.
        jassert (File::isAbsolutePath (sourceFile));
 
        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
{
    MultipleInstanceHandler (const String& appName)
        : appLock ("juceAppLock_" + appName)
    {
    }
 
    bool sendCommandLineToPreexistingInstance()
    {
        if (appLock.enter (0))
            return false;
 
        if (auto* app = JUCEApplicationBase::getInstance())
        {
            MessageManager::broadcastMessage (app->getApplicationName() + "/" + app->getCommandLineParameters());
            return true;
        }
 
        jassertfalse;
        return false;
    }
 
    void actionListenerCallback (const String& message) override
    {
        if (auto* app = JUCEApplicationBase::getInstance())
        {
            auto 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.reset (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 (auto argv = CommandLineToArgvW (GetCommandLineW(), &argc))
    {
        s = StringArray (argv + 1, argc - 1);
        LocalFree (argv);
    }
 
    return s;
}
 
#else
 
#if JUCE_IOS && JUCE_MODULE_AVAILABLE_juce_gui_basics
 extern int juce_iOSMain (int argc, const char* argv[], void* classPtr);
#endif
 
#if JUCE_MAC
 extern void initialiseNSApplication();
#endif
 
#if (JUCE_LINUX || JUCE_BSD) && JUCE_MODULE_AVAILABLE_juce_gui_extra && (! defined(JUCE_WEB_BROWSER) || JUCE_WEB_BROWSER)
 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 { CharPointer_UTF8 (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[])
{
    JUCE_AUTORELEASEPOOL
    {
        juce_argc = argc;
        juce_argv = argv;
 
       #if JUCE_MAC
        initialiseNSApplication();
       #endif
 
       #if (JUCE_LINUX || JUCE_BSD) && JUCE_MODULE_AVAILABLE_juce_gui_extra && (! defined(JUCE_WEB_BROWSER) || JUCE_WEB_BROWSER)
        if (argc >= 2 && String (argv[1]) == "--juce-gtkwebkitfork-child")
            return juce_gtkWebkitMain (argc, argv);
       #endif
 
       #if JUCE_IOS && JUCE_MODULE_AVAILABLE_juce_gui_basics
        return juce_iOSMain (argc, argv, iOSCustomDelegate);
       #else
 
        return JUCEApplicationBase::main();
       #endif
    }
}
 
#endif
 
//==============================================================================
int JUCEApplicationBase::main()
{
    ScopedJuceInitialiser_GUI libraryInitialiser;
    jassert (createInstance != nullptr);
 
    const std::unique_ptr<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 (auto* mih = multipleInstanceHandler.get())
        MessageManager::getInstance()->registerBroadcastListener (mih);
   #endif
 
    return true;
}
 
int JUCEApplicationBase::shutdownApp()
{
    jassert (JUCEApplicationBase::getInstance() == this);
 
   #if JUCE_HANDLE_MULTIPLE_INSTANCES
    if (auto* mih = multipleInstanceHandler.get())
        MessageManager::getInstance()->deregisterBroadcastListener (mih);
   #endif
 
    JUCE_TRY
    {
        // give the app a chance to clean up..
        shutdown();
    }
    JUCE_CATCH_EXCEPTION
 
    multipleInstanceHandler.reset();
    return getApplicationReturnValue();
}
 
} // namespace juce