1

public/appframework/IAppSystemGroup.h

@@ -0,0 +1,265 @@
+//========= Copyright Valve Corporation, All rights reserved. ============//
+//
+// The copyright to the contents herein is the property of Valve, L.L.C.
+// The contents may be used and/or copied only with the written permission of
+// Valve, L.L.C., or in accordance with the terms and conditions stipulated in
+// the agreement/contract under which the contents have been supplied.
+//
+// Purpose: Defines a group of app systems that all have the same lifetime
+// that need to be connected/initialized, etc. in a well-defined order
+//
+// $Revision: $
+// $NoKeywords: $
+//=============================================================================
+
+#ifndef IAPPSYSTEMGROUP_H
+#define IAPPSYSTEMGROUP_H
+
+#ifdef _WIN32
+#pragma once
+#endif
+
+
+#include "tier1/interface.h"
+#include "tier1/utlvector.h"
+#include "tier1/utldict.h"
+#include "IAppSystem.h"
+
+//-----------------------------------------------------------------------------
+// forward declarations
+//-----------------------------------------------------------------------------
+class IAppSystem;
+class CSysModule;
+class IBaseInterface;
+class IFileSystem;
+
+//-----------------------------------------------------------------------------
+// Handle to a DLL
+//-----------------------------------------------------------------------------
+typedef int AppModule_t;
+
+enum
+{
+	APP_MODULE_INVALID = (AppModule_t)~0
+};
+
+
+//-----------------------------------------------------------------------------
+// NOTE: The following methods must be implemented in your application
+// although they can be empty implementations if you like...
+//-----------------------------------------------------------------------------
+abstract_class IAppSystemGroup
+{
+public:
+	// An installed application creation function, you should tell the group
+	// the DLLs and the singleton interfaces you want to instantiate.
+	// Return false if there's any problems and the app will abort
+	virtual bool Create( ) = 0;
+
+	// Allow the application to do some work after AppSystems are connected but 
+	// they are all Initialized.
+	// Return false if there's any problems and the app will abort
+	virtual bool PreInit() = 0;
+
+	// Main loop implemented by the application
+	virtual int Main( ) = 0;
+
+	// Allow the application to do some work after all AppSystems are shut down
+	virtual void PostShutdown() = 0;
+
+	// Call an installed application destroy function, occurring after all modules
+	// are unloaded
+	virtual void Destroy() = 0;
+};
+
+
+//-----------------------------------------------------------------------------
+// Specifies a module + interface name for initialization
+//-----------------------------------------------------------------------------
+struct AppSystemInfo_t
+{
+	const char *m_pModuleName;
+	const char *m_pInterfaceName;
+};
+
+
+//-----------------------------------------------------------------------------
+// This class represents a group of app systems that all have the same lifetime
+// that need to be connected/initialized, etc. in a well-defined order
+//-----------------------------------------------------------------------------
+class CAppSystemGroup : public IAppSystemGroup
+{
+public:
+	// Used to determine where we exited out from the system
+	enum AppSystemGroupStage_t
+	{
+		CREATION = 0,
+		CONNECTION,
+		PREINITIALIZATION,
+		INITIALIZATION,
+		SHUTDOWN,
+		POSTSHUTDOWN,
+		DISCONNECTION,
+		DESTRUCTION,
+
+		NONE,	// This means no error
+	};
+
+public:
+	// constructor
+	CAppSystemGroup( CAppSystemGroup *pParentAppSystem = NULL );
+
+	// Runs the app system group.
+	// First, modules are loaded, next they are connected, followed by initialization
+	// Then Main() is run
+	// Then modules are shut down, disconnected, and unloaded
+	int Run( );
+
+	// Use this version in cases where you can't control the main loop and
+	// expect to be ticked
+	virtual int Startup();
+	virtual void Shutdown();
+
+	// Returns the stage at which the app system group ran into an error
+	AppSystemGroupStage_t GetErrorStage() const;
+
+protected:
+	// These methods are meant to be called by derived classes of CAppSystemGroup
+
+	// Methods to load + unload DLLs
+	AppModule_t LoadModule( const char *pDLLName );
+	AppModule_t LoadModule( CreateInterfaceFn factory );
+
+	// Method to add various global singleton systems 
+	IAppSystem *AddSystem( AppModule_t module, const char *pInterfaceName );
+	void AddSystem( IAppSystem *pAppSystem, const char *pInterfaceName );
+
+	// Simpler method of doing the LoadModule/AddSystem thing.
+	// Make sure the last AppSystemInfo has a NULL module name
+	bool AddSystems( AppSystemInfo_t *pSystems );
+
+	// Method to look up a particular named system...
+	void *FindSystem( const char *pInterfaceName );
+
+	// Gets at a class factory for the topmost appsystem group in an appsystem stack
+	static CreateInterfaceFn GetFactory();
+
+private:
+	int OnStartup();
+	void OnShutdown();
+
+	void UnloadAllModules( );
+	void RemoveAllSystems();
+
+	// Method to connect/disconnect all systems
+	bool ConnectSystems( );
+	void DisconnectSystems();
+
+	// Method to initialize/shutdown all systems
+	InitReturnVal_t InitSystems();
+	void ShutdownSystems();
+ 
+	// Gets at the parent appsystem group
+	CAppSystemGroup *GetParent();
+
+	// Loads a module the standard way
+	virtual CSysModule *LoadModuleDLL( const char *pDLLName );
+
+	void	ReportStartupFailure( int nErrorStage, int nSysIndex );
+
+	struct Module_t
+	{
+		CSysModule *m_pModule;
+		CreateInterfaceFn m_Factory;
+		char *m_pModuleName;
+	};
+
+	CUtlVector<Module_t> m_Modules;
+	CUtlVector<IAppSystem*> m_Systems;
+	CUtlDict<int, unsigned short> m_SystemDict;
+	CAppSystemGroup *m_pParentAppSystem;
+	AppSystemGroupStage_t m_nErrorStage;
+
+	friend void *AppSystemCreateInterfaceFn(const char *pName, int *pReturnCode);
+	friend class CSteamAppSystemGroup;
+};
+
+
+//-----------------------------------------------------------------------------
+// This class represents a group of app systems that are loaded through steam
+//-----------------------------------------------------------------------------
+class CSteamAppSystemGroup : public CAppSystemGroup
+{
+public:
+	CSteamAppSystemGroup( IFileSystem *pFileSystem = NULL, CAppSystemGroup *pParentAppSystem = NULL );
+
+	// Used by CSteamApplication to set up necessary pointers if we can't do it in the constructor
+	void Setup( IFileSystem *pFileSystem, CAppSystemGroup *pParentAppSystem );
+
+protected:
+	// Sets up the search paths
+	bool SetupSearchPaths( const char *pStartingDir, bool bOnlyUseStartingDir, bool bIsTool );
+
+	// Returns the game info path. Only works if you've called SetupSearchPaths first
+	const char *GetGameInfoPath() const;
+
+private:
+	virtual CSysModule *LoadModuleDLL( const char *pDLLName );
+
+	IFileSystem *m_pFileSystem;
+	char m_pGameInfoPath[ MAX_PATH ];
+};
+
+
+//-----------------------------------------------------------------------------
+// Helper empty decorator implementation of an IAppSystemGroup
+//-----------------------------------------------------------------------------
+template< class CBaseClass > 
+class CDefaultAppSystemGroup : public CBaseClass
+{
+public:
+	virtual bool Create( ) { return true; }
+	virtual bool PreInit() { return true; }
+	virtual void PostShutdown() {}
+	virtual void Destroy() {}
+};
+
+
+//-----------------------------------------------------------------------------
+// Special helper for game info directory suggestion
+//-----------------------------------------------------------------------------
+
+class CFSSteamSetupInfo;	// Forward declaration
+
+//
+// SuggestGameInfoDirFn_t
+//		Game info suggestion function.
+//		Provided by the application to possibly detect the suggested game info
+//		directory and initialize all the game-info-related systems appropriately.
+// Parameters:
+//		pFsSteamSetupInfo		steam file system setup information if available.
+//		pchPathBuffer			buffer to hold game info directory path on return.
+//		nBufferLength			length of the provided buffer to hold game info directory path.
+//		pbBubbleDirectories		should contain "true" on return to bubble the directories up searching for game info file.
+// Return values:
+//		Returns "true" if the game info directory path suggestion is available and
+//		was successfully copied into the provided buffer.
+//		Returns "false" otherwise, interpreted that no suggestion will be used.
+//
+typedef bool ( * SuggestGameInfoDirFn_t ) ( CFSSteamSetupInfo const *pFsSteamSetupInfo, char *pchPathBuffer, int nBufferLength, bool *pbBubbleDirectories );
+
+//
+// SetSuggestGameInfoDirFn
+//		Installs the supplied game info directory suggestion function.
+// Parameters:
+//		pfnNewFn				the new game info directory suggestion function.
+// Returns:
+//		The previously installed suggestion function or NULL if none was installed before.
+//		This function never fails.
+//
+SuggestGameInfoDirFn_t SetSuggestGameInfoDirFn( SuggestGameInfoDirFn_t pfnNewFn );
+
+
+#endif // APPSYSTEMGROUP_H
+
+