return "" -> return NULL

stepmania/src/AnnouncerManager.cpp

@@ -84,7 +84,7 @@ static const char *aliases[][2] = {
 CString AnnouncerManager::GetPathTo( CString sAnnouncerName, CString sFolderName )
 {
 	if(sAnnouncerName == "")
-		return ""; /* announcer disabled */
+		return NULL; /* announcer disabled */
 
 	const CString AnnouncerPath = GetAnnouncerDirFromName(sAnnouncerName);
 
@@ -112,7 +112,7 @@ CString AnnouncerManager::GetPathTo( CString sAnnouncerName, CString sFolderName
 	temp.Open( AnnouncerPath+sFolderName + "/announcer files go here.txt", RageFile::WRITE );
 #endif
 	
-	return "";
+	return NULL;
 }
 
 CString AnnouncerManager::GetPathTo( CString sFolderName )

stepmania/src/Character.cpp

@@ -66,7 +66,7 @@ CString GetRandomFileInDir( CString sDir )
 	CStringArray asFiles;
 	GetDirListing( sDir, asFiles, false, true );
 	if( asFiles.empty() )
-		return "";
+		return NULL;
 	else
 		return asFiles[rand()%asFiles.size()];
 }
@@ -78,7 +78,7 @@ CString Character::GetModelPath() const
 	if( DoesFileExist(s) )
 		return s; 
 	else 
-		return "";
+		return NULL;
 }
 
 CString Character::GetRestAnimationPath() const	{ return DerefRedir(GetRandomFileInDir(m_sCharDir + "Rest/")); }
@@ -92,7 +92,7 @@ CString Character::GetTakingABreakPath() const
 	GetDirListing( m_sCharDir+"break.gif", as, false, true );
 	GetDirListing( m_sCharDir+"break.bmp", as, false, true );
 	if( as.empty() )
-		return "";
+		return NULL;
 	else
 		return as[0];
 }
@@ -115,7 +115,7 @@ CString Character::GetSongSelectIconPath() const
 		GetDirListing( m_sCharDir+"icon.gif", as, false, true );
 		GetDirListing( m_sCharDir+"icon.bmp", as, false, true );
 		if( as.empty() )
-			return "";
+			return NULL;
 		else
 			return as[0];
 	}
@@ -141,7 +141,7 @@ CString Character::GetStageIconPath() const
 		GetDirListing( m_sCharDir+"card.gif", as, false, true );
 		GetDirListing( m_sCharDir+"card.bmp", as, false, true );
 		if( as.empty() )
-			return "";
+			return NULL;
 		else
 			return as[0];
 	}

stepmania/src/Command.cpp

@@ -17,7 +17,7 @@ void IncorrectNumberArgsWarning( const Command &command, int iMaxIndexAccessed )
 CString Command::GetName() const 
 {
 	if( m_vsArgs.empty() )
-		return "";
+		return NULL;
 	CString s = m_vsArgs[0];
 	s.MakeLower();
 	return s;

stepmania/src/CourseUtil.cpp

@@ -278,7 +278,7 @@ CString CourseID::ToString() const
 		return sPath;
 	if( !sFullTitle.empty() )
 		return sFullTitle;
-	return "";
+	return NULL;
 }
 
 bool CourseID::IsValid() const

stepmania/src/CryptManager.cpp

@@ -244,7 +244,7 @@ CString CryptManager::GetMD5( CString fn )
        if( !file.Open( fn, RageFile::READ ) )
        {
                LOG->Warn( "GetMD5: Failed to open file '%s'", fn.c_str() );
-               return "";
+               return NULL;
        }
 
        MD5Init(&md5c);

stepmania/src/DateTime.cpp

@@ -197,7 +197,7 @@ static const CString MONTH_TO_NAME[MONTHS_IN_YEAR] =
 CString MonthToString( int iMonthIndex )
 {
 	if( iMonthIndex < 0 || iMonthIndex >= (int) sizeof(MONTH_TO_NAME) )
-		return "";
+		return NULL;
 	return MONTH_TO_NAME[iMonthIndex];
 }
 LuaFunction( MonthToString, MonthToString( IArg(1) ) );

stepmania/src/Font.cpp

@@ -695,7 +695,7 @@ CString FontPageSettings::MapRange( CString sMapping, int iMapOffset, int iGlyph
 			iCount--;
 		}
 
-		return "";
+		return NULL;
 	}
 
 	const wchar_t *pMapping = FontCharmaps::get_char_map( sMapping );
@@ -726,7 +726,7 @@ CString FontPageSettings::MapRange( CString sMapping, int iMapOffset, int iGlyph
 	if( iCount )
 		return "Map overflow"; /* there aren't enough characters in the map */
 
-	return "";
+	return NULL;
 }
 
 static CStringArray LoadStack;

stepmania/src/GameManager.cpp

@@ -2764,7 +2764,7 @@ CString GameManager::GetMenuButtonSecondaryFunction( const Game *pGame, GameButt
 	 * it) and/or map to a menu button (if m_DedicatedMenuButton or m_SecondaryMenuButton
 	 * map to it).
 	 *
-	 * If a button is only used in gameplay or is only used in menus, return ""; the 
+	 * If a button is only used in gameplay or is only used in menus, return NULL; the 
 	 * primary description is sufficient.
 	 *
 	 * If a button is used in both gameplay and menus, return szSecondaryNames[] for
@@ -2800,12 +2800,12 @@ CString GameManager::GetMenuButtonSecondaryFunction( const Game *pGame, GameButt
 	FOREACH_MenuButton(m)
 	{
 		if( !bUsedInGameplay && pGame->m_DedicatedMenuButton[m] == gb )
-			return "";
+			return NULL;
 		else if( bUsedInGameplay && pGame->m_SecondaryMenuButton[m] == gb )
 			return szSecondaryNames[m];
 	}
 
-	return ""; // only used in gameplay
+	return NULL; // only used in gameplay
 }
 
 

stepmania/src/MsdFile.cpp

@@ -160,8 +160,8 @@ void MsdFile::ReadFromString( const CString &sString )
 
 CString MsdFile::GetParam(unsigned val, unsigned par) const
 {
-	if(val >= GetNumValues()) return "";
-	if(par >= GetNumParams(val)) return "";
+	if(val >= GetNumValues()) return NULL;
+	if(par >= GetNumParams(val)) return NULL;
 
 	return values[val].params[par];
 }

stepmania/src/MsdFile.h

@@ -11,7 +11,7 @@ public:
 	{
 		vector<CString> params;
 
-		CString operator[](unsigned i) const { if(i >= params.size()) return ""; return params[i]; }
+		CString operator[](unsigned i) const { if(i >= params.size()) return NULL; return params[i]; }
 	};
 
 	virtual ~MsdFile() { }

stepmania/src/NetworkSyncManager.cpp

@@ -13,7 +13,7 @@ NetworkSyncManager::~NetworkSyncManager () { }
 void NetworkSyncManager::CloseConnection() { }
 void NetworkSyncManager::PostStartUp(const CString& ServerIP ) { }
 bool NetworkSyncManager::Connect(const CString& addy, unsigned short port) { return false; }
-CString NetworkSyncManager::GetServerName() { return ""; }
+CString NetworkSyncManager::GetServerName() { return NULL; }
 void NetworkSyncManager::ReportNSSOnOff(int i) { }
 void NetworkSyncManager::ReportTiming(float offset, int PlayerNumber) { }
 void NetworkSyncManager::ReportScore(int playerID, int step, int score, int combo) { }
@@ -25,7 +25,7 @@ void NetworkSyncManager::Update( float fDeltaTime ) { }
 bool NetworkSyncManager::ChangedScoreboard(int Column) { return false; }
 void NetworkSyncManager::SendChat(const CString& message) { }
 void NetworkSyncManager::SelectUserSong() { }
-CString NetworkSyncManager::MD5Hex( const CString &sInput ) { return ""; }
+CString NetworkSyncManager::MD5Hex( const CString &sInput ) { return NULL; }
 int NetworkSyncManager::GetSMOnlineSalt() { return 0; }
 #else
 #include "ezsockets.h"

stepmania/src/NoteSkinManager.cpp

@@ -273,7 +273,7 @@ CString NoteSkinManager::GetPathFromDirAndFile( const CString &sDir, const CStri
 	GetDirListing( sDir+sFileName+"*",		matches, false, true );
 
 	if( matches.empty() )
-		return "";
+		return NULL;
 
 	if( matches.size() > 1 )
 	{

stepmania/src/Profile.cpp

@@ -186,7 +186,7 @@ CString Profile::GetDisplayNameOrHighScoreName() const
 	else if( !m_sLastUsedHighScoreName.empty() )
 		return m_sLastUsedHighScoreName;
 	else
-		return "";
+		return NULL;
 }
 
 Character *Profile::GetCharacter() const

stepmania/src/ProfileManager.cpp

@@ -538,7 +538,7 @@ CString ProfileManager::GetProfileDirImportedFrom( ProfileSlot slot ) const
 	case PROFILE_SLOT_PLAYER_2:
 		return m_sProfileDirImportedFrom[slot];
 	case PROFILE_SLOT_MACHINE:
-		return "";
+		return NULL;
 	default:
 		ASSERT(0);
 	}

stepmania/src/RageDisplay.cpp

@@ -54,20 +54,20 @@ CString RageDisplay::SetVideoMode( VideoModeParams p, bool &bNeedReloadTextures
 	CString err;
 	err = this->TryVideoMode(p,bNeedReloadTextures);
 	if( err == "" )
-		return "";
+		return NULL;
 	LOG->Trace( "TryVideoMode failed: %s", err.c_str() );
 	
 	// fall back
 	p.windowed = false;
 	if( this->TryVideoMode(p,bNeedReloadTextures) == "" )
-		return "";
+		return NULL;
 	p.bpp = 16;
 	if( this->TryVideoMode(p,bNeedReloadTextures) == "" )
-		return "";
+		return NULL;
 	p.width = 640;
 	p.height = 480;
 	if( this->TryVideoMode(p,bNeedReloadTextures) == "" )
-		return "";
+		return NULL;
 
 	return ssprintf( "SetVideoMode failed: %s", err.c_str() );
 }

stepmania/src/RageDisplay.h

@@ -222,7 +222,7 @@ public:
 	};
 	bool SaveScreenshot( CString sPath, GraphicsFileFormat format );
 
-	virtual CString GetTextureDiagnostics( unsigned id ) const { return ""; }
+	virtual CString GetTextureDiagnostics( unsigned id ) const { return NULL; }
 	virtual RageSurface* CreateScreenshot() = 0;	// allocates a surface.  Caller must delete it.
 
 protected:
@@ -235,7 +235,7 @@ protected:
 	virtual void DrawLineStripInternal( const RageSpriteVertex v[], int iNumVerts, float LineWidth );
 	virtual void DrawCircleInternal( const RageSpriteVertex &v, float radius );
 
-	// Return "" if mode change was successful, an error message otherwise.
+	// return NULL if mode change was successful, an error message otherwise.
 	// bNewDeviceOut is set true if a new device was created and textures
 	// need to be reloaded.
 	virtual CString TryVideoMode( VideoModeParams params, bool &bNewDeviceOut ) = 0;

stepmania/src/RageDisplay_D3D.cpp

@@ -392,7 +392,7 @@ CString SetD3DParams( bool &bNewDeviceOut )
 		}
 	}
 
-	return "";
+	return NULL;
 }
 
 /* If the given parameters have failed, try to lower them. */
@@ -605,7 +605,7 @@ CString RageDisplay_D3D::TryVideoMode( VideoModeParams p, bool &bNewDeviceOut )
 	/* Palettes were lost by Reset(), so mark them unloaded. */
 	g_TexResourceToPaletteIndex.clear();
 
-	return "";	// mode change successful
+	return NULL;	// mode change successful
 }
 
 void RageDisplay_D3D::ResolutionChanged()

stepmania/src/RageDisplay_Null.h

@@ -74,7 +74,7 @@ protected:
 	void DrawLineStripInternal( const RageSpriteVertex v[], int iNumVerts, float LineWidth ) { }
 
 	VideoModeParams m_Params;
-	CString TryVideoMode( VideoModeParams params, bool &bNewDeviceOut ) { m_Params = params; return ""; }
+	CString TryVideoMode( VideoModeParams params, bool &bNewDeviceOut ) { m_Params = params; return NULL; }
 	RageSurface* CreateScreenshot();
 	void SetViewport(int shift_left, int shift_down) { }
 	RageMatrix GetOrthoMatrix( float l, float r, float b, float t, float zn, float zf ); 

stepmania/src/RageDisplay_OGL.cpp

@@ -334,7 +334,7 @@ CString GetInfoLog( GLhandleARB h )
 	GLint iLength;
 	GLExt.glGetObjectParameterivARB( h, GL_OBJECT_INFO_LOG_LENGTH_ARB, &iLength );
 	if( !iLength )
-		return "";
+		return NULL;
 
 	GLcharARB *pInfoLog = new GLcharARB[iLength];
 	GLExt.glGetInfoLogARB( h, iLength, &iLength, pInfoLog );
@@ -477,7 +477,7 @@ CString RageDisplay_OGL::Init( VideoModeParams p, bool bAllowUnacceleratedRender
 
 	InitScalingScript();
 
-	return "";
+	return NULL;
 }
 
 #if defined(UNIX) && defined(HAVE_LIBXTST)
@@ -698,7 +698,7 @@ CString RageDisplay_OGL::TryVideoMode( VideoModeParams p, bool &bNewDeviceOut )
 	
 	ResolutionChanged();
 
-	return "";	// successfully set mode
+	return NULL;	// successfully set mode
 }
 
 void RageDisplay_OGL::SetViewport(int shift_left, int shift_down)
@@ -1884,7 +1884,7 @@ void RageDisplay_OGL::SetLineWidth( float fWidth )
 
 CString RageDisplay_OGL::GetTextureDiagnostics( unsigned id ) const
 {
-	return "";
+	return NULL;
 }
 
 void RageDisplay_OGL::SetAlphaTest( bool b )

stepmania/src/RageFile.cpp

@@ -33,7 +33,7 @@ RageFileBasic *RageFile::Copy() const
 CString RageFile::GetPath() const
 {
 	if ( !IsOpen() )
-		return "";
+		return NULL;
 
 	CString sRet = m_File->GetDisplayPath();
 	if( sRet != "" )
@@ -219,7 +219,7 @@ void FileReading::ReadBytes( RageFileBasic &f, void *buf, int size, CString &sEr
 CString FileReading::ReadString( RageFileBasic &f, int size, CString &sError )
 {
 	if( sError.size() != 0 )
-		return "";
+		return NULL;
 
 	CString sBuf;
 	int ret = f.Read( sBuf, size );

stepmania/src/RageFileBasic.h

@@ -42,7 +42,7 @@ public:
 	virtual int Flush() = 0;
 
 	/* This returns a descriptive path for the file, or "". */
-	virtual CString GetDisplayPath() const { return ""; }
+	virtual CString GetDisplayPath() const { return NULL; }
 
 	virtual RageFileBasic *Copy() const = 0;
 
@@ -88,7 +88,7 @@ public:
 	bool GetCRC32( uint32_t *iRet );
 
 	virtual int GetFileSize() const = 0;
-	virtual CString GetDisplayPath() const { return ""; }
+	virtual CString GetDisplayPath() const { return NULL; }
 	virtual RageFileBasic *Copy() const { FAIL_M( "Copying unimplemented" ); }
 
 protected:

stepmania/src/RageFileManager.cpp

@@ -329,11 +329,11 @@ CString LoadedDriver::GetPath( const CString &path )
 	if( path.size() >= 2 && path[1] == '@' )
 	{
 		if( MountPoint.size() < 2 || MountPoint[1] != '@' )
-			return "";
+			return NULL;
 	}
 	
 	if( path.Left( MountPoint.size() ).CompareNoCase( MountPoint ) )
-		return ""; /* no match */
+		return NULL; /* no match */
 
 	/* Add one, so we don't cut off the leading slash. */
 	CString sRet = path.Right( path.size() - MountPoint.size() + 1 );

stepmania/src/RageInputDevice.cpp

@@ -270,8 +270,8 @@ CString DeviceButtonToString( InputDevice device, DeviceButton i )
 	case DEVICE_PUMP2:		return PumpPadButtonToString( (PumpPadButton)i );
 	case DEVICE_MIDI:		return MidiButtonToString( i );
 	case DEVICE_PARA1:		return ParaPadButtonToString( (ParaPadButton)i );
-	case DEVICE_NONE:		return "";
-	default:	ASSERT(0);	return "";
+	case DEVICE_NONE:		return NULL;
+	default:	ASSERT(0);	return NULL;
 	}
 }
 
@@ -337,7 +337,7 @@ int GetNumDeviceButtons( InputDevice device )
 CString DeviceInput::toString() const
 {
 	if( device == DEVICE_NONE )
-		return "";
+		return NULL;
 
 	CString s = InputDeviceToString(device) + "_" + DeviceButtonToString(device,button);
 	return s;

stepmania/src/RageSoundReader_WAV.cpp

@@ -357,7 +357,7 @@ public:
 CString ReadString( RageFile &f, int iSize, CString &sError )
 {
 	if( sError.size() != 0 )
-		return "";
+		return NULL;
 
 	CString sBuf;
 	char *pBuf = sBuf.GetBuffer( iSize );

stepmania/src/RageUtil.cpp

@@ -277,7 +277,7 @@ CString werr_ssprintf( int err, const char *fmt, ...)
 CString ConvertWstringToACP( wstring s )
 {
 	if( s.empty() )
-		return "";
+		return NULL;
 
 	int iBytes = WideCharToMultiByte( CP_ACP, 0, s.data(), s.size(), 
 					NULL, 0, NULL, FALSE );
@@ -301,7 +301,7 @@ CString ConvertUTF8ToACP( CString s )
 CString join( const CString &Deliminator, const CStringArray& Source)
 {
 	if( Source.empty() )
-		return "";
+		return NULL;
 
 	CString csTmp;
 
@@ -317,7 +317,7 @@ CString join( const CString &Deliminator, const CStringArray& Source)
 CString join( const CString &Delimitor, CStringArray::const_iterator begin, CStringArray::const_iterator end )
 {
 	if( begin == end )
-		return "";
+		return NULL;
 
 	CString ret;
 	while( begin != end )
@@ -512,11 +512,11 @@ CString GetExtension( const CString &sPath )
 {
 	size_t pos = sPath.rfind( '.' );
 	if( pos == sPath.npos )
-		return "";
+		return NULL;
 
 	size_t slash = sPath.find( '/', pos );
 	if( slash != sPath.npos )
-		return ""; /* rare: path/dir.ext/fn */
+		return NULL; /* rare: path/dir.ext/fn */
 
 	return sPath.substr( pos+1, sPath.size()-pos+1 );
 }
@@ -660,6 +660,15 @@ void StripCrnl(CString &s)
 		s.erase(s.size()-1);
 }
 
+bool EndsWith( const CString &sTestThis, const CString &sEnding )
+{
+	ASSERT( !sEnding.empty() );
+
+	if( sTestThis.size() < sEnding.size() )
+		return false;
+	return sTestThis.Right( sEnding.size() ) == sEnding;
+}
+
 void StripCvs( vector<CString> &vs )
 {
 	for( unsigned i=0; i<vs.size(); i++ )
@@ -686,7 +695,7 @@ CString DerefRedir(const CString &_path)
 
 		/* Empty is invalid. */
 		if( sNewFileName == "" )
-			return "";
+			return NULL;
 
 		FixSlashesInPlace( sNewFileName );
 
@@ -1244,7 +1253,7 @@ CString Basename( const CString &dir )
 {
 	size_t  end = dir.find_last_not_of( "/\\" );
 	if( end == dir.npos )
-		return "";
+		return NULL;
 
 	size_t  start = dir.find_last_of( "/\\", end );
 	if( start == dir.npos )
@@ -1286,7 +1295,7 @@ CString Dirname( const CString &dir )
 CString Capitalize( const CString &s )	
 {
 	if( s.GetLength()==0 )
-		return "";
+		return NULL;
 	CString s2 = s;
 	/* XXX: utf-8 */
 	if( !(s2[0] & 0x80) )

stepmania/src/RageUtil.h

@@ -313,6 +313,7 @@ inline T Decrement( T a ) { --a; return a; }
 void TrimLeft(CString &str, const char *s = "\r\n\t ");
 void TrimRight(CString &str, const char *s = "\r\n\t ");
 void StripCrnl(CString &s);
+bool EndsWith( const CString &sTestThis, const CString &sEnding );
 
 void StripCvs( vector<CString> &vs );	// remove all items that end in "cvs"
 

stepmania/src/RageUtil_BackgroundLoader.cpp

@@ -69,11 +69,11 @@ BackgroundLoader::~BackgroundLoader()
 CString BackgroundLoader::GetRequest()
 {
 	if( !g_bEnableBackgroundLoading )
-		return "";
+		return NULL;
 
 	LockMut( m_Mutex );
 	if( !m_CacheRequests.size() )
-		return "";
+		return NULL;
 
 	CString ret;
 	ret = m_CacheRequests.front();

stepmania/src/ScreenEdit.cpp

@@ -540,7 +540,7 @@ static CString GetOneBakedRandomFile( Song *pSong, bool bTryGenre = true )
 	if( !vsNamesOut.empty() )
 		return vsNamesOut[rand()%vsNamesOut.size()];
 	else
-		return "";
+		return NULL;
 }
 
 static MenuDef g_InsertTapAttack(

stepmania/src/ScreenEnding.cpp

@@ -43,7 +43,7 @@ CString GetStatsLineTitle( PlayerNumber pn, EndingStatsLine line )
 				CourseDifficulty cd = (CourseDifficulty)(DIFFICULTY_EASY+line-PERCENT_COMPLETE_EASY);
 				ASSERT( cd >= 0 && cd < NUM_COURSE_DIFFICULTIES );
 				if( !GAMESTATE->IsCourseDifficultyShown(cd) )
-					return "";
+					return NULL;
 				return CourseDifficultyToThemedString(cd);
 			}
 			else
@@ -53,7 +53,7 @@ CString GetStatsLineTitle( PlayerNumber pn, EndingStatsLine line )
 				return DifficultyToThemedString(dc);
 			}
 		}
-	default:	ASSERT(0);	return "";
+	default:	ASSERT(0);	return NULL;
 	}
 }
 
@@ -107,7 +107,7 @@ CString GetStatsLineValue( PlayerNumber pn, EndingStatsLine line )
 				CourseDifficulty cd = (CourseDifficulty)(DIFFICULTY_EASY+line-PERCENT_COMPLETE_EASY);
 				ASSERT( cd >= 0 && cd < NUM_COURSE_DIFFICULTIES );
 				if( !GAMESTATE->IsCourseDifficultyShown(cd) )
-					return "";
+					return NULL;
 				CString sDifficulty = CourseDifficultyToThemedString(cd);
 				fPercent = pProfile->GetCoursesPercentComplete(st,cd);
 			}
@@ -120,7 +120,7 @@ CString GetStatsLineValue( PlayerNumber pn, EndingStatsLine line )
 			}
 			return ssprintf( "%05.2f%%", fPercent*100 );
 		}
-	default:	ASSERT(0);	return "";
+	default:	ASSERT(0);	return NULL;
 	}
 }
 

stepmania/src/ScreenMessage.cpp

@@ -45,7 +45,7 @@ CString	ASMHClass::NumberToString( ScreenMessage SM )
 		if ( SM == iter->second )
 			return (*iter).first;
 
-	return "";
+	return NULL;
 }
 
 /*

stepmania/src/ScreenOptions.cpp

@@ -367,7 +367,7 @@ CString ScreenOptions::GetExplanationText( int iRow ) const
 	bool bAllowExplanation = row.GetRowDef().m_bAllowExplanation;
 	bool bShowExplanations = bAllowExplanation && SHOW_EXPLANATIONS.GetValue();
 	if( !bShowExplanations )
-		return "";
+		return NULL;
 
 	CString sLineName = row.GetRowDef().m_sName;
 	ASSERT( !sLineName.empty() );

stepmania/src/ScreenPackages.cpp

@@ -408,7 +408,7 @@ CString ScreenPackages::URLEncode( const CString &URL )
 CString ScreenPackages::StripOutContainers( const CString & In )
 {
 	if( In.size() == 0 )
-		return "";
+		return NULL;
 
 	unsigned i = 0;
 	char t = In.at(i);

stepmania/src/ScreenProfileOptions.cpp

@@ -228,7 +228,7 @@ CString ScreenProfileOptions::GetSelectedProfileID()
 	const OptionRow &row = *m_pRows[GetCurrentRow()];
 	const int Selection = row.GetOneSharedSelection();
 	if( !Selection )
-		return "";
+		return NULL;
 	return vsProfiles[ Selection-1 ];
 }
 
@@ -237,7 +237,7 @@ CString ScreenProfileOptions::GetSelectedProfileName()
 	const OptionRow &row = *m_pRows[GetCurrentRow()];
 	const int Selection = row.GetOneSharedSelection();
 	if( !Selection )
-		return "";
+		return NULL;
 	return g_ProfileOptionsLines[PO_PLAYER1].m_vsChoices[ Selection ];
 }
 

stepmania/src/ScreenSMOnlineLogin.cpp

@@ -169,7 +169,7 @@ CString ScreenSMOnlineLogin::GetSelectedProfileID()
 	const OptionRow &row = *m_pRows[GetCurrentRow()];
 	const int Selection = row.GetOneSharedSelection();
 	if( !Selection )
-		return "";
+		return NULL;
 	return vsProfiles[ Selection-1 ];
 }
 

stepmania/src/ScreenSystemLayer.cpp

@@ -132,7 +132,7 @@ void ScreenSystemLayer::ReloadCreditsText()
 CString ScreenSystemLayer::GetCreditsMessage( PlayerNumber pn ) const
 {
 	if( (bool)CREDITS_JOIN_ONLY && !GAMESTATE->PlayersCanJoin() )
-		return "";
+		return NULL;
 
 	bool bShowCreditsMessage;
 	if( SCREENMAN && SCREENMAN->GetTopScreen() && SCREENMAN->GetTopScreen()->GetScreenType() == system_menu )
@@ -160,7 +160,7 @@ CString ScreenSystemLayer::GetCreditsMessage( PlayerNumber pn ) const
 			else if( GAMESTATE->PlayersCanJoin() )
 				return CREDITS_INSERT_CARD.GetValue();
 			else
-				return "";
+				return NULL;
 
 		case MEMORY_CARD_STATE_ERROR: 		return THEME->GetMetric( m_sName, "CreditsCard" + MEMCARDMAN->GetCardError(pn) );
 		case MEMORY_CARD_STATE_TOO_LATE:	return CREDITS_CARD_TOO_LATE.GetValue();

stepmania/src/Song.cpp

@@ -1245,7 +1245,7 @@ vector<BackgroundChange> &Song::GetForegroundChanges()
 CString GetSongAssetPath( CString sPath, const CString &sSongPath )
 {
 	if( sPath == "" )
-		return "";
+		return NULL;
 
 	/* If there's no path in the file, the file is in the same directory
 	 * as the song.  (This is the preferred configuration.) */
@@ -1264,7 +1264,7 @@ CString GetSongAssetPath( CString sPath, const CString &sSongPath )
 	/* If the path still begins with "../", then there were an unreasonable number
 	 * of them at the beginning of the path.  Ignore the path entirely. */
 	if( sPath.Left(3) == "../" )
-		return "";
+		return NULL;
 
 	return sPath;
 }

stepmania/src/SongManager.cpp

@@ -316,7 +316,7 @@ CString SongManager::GetSongGroupBannerPath( CString sSongGroup )
 			return m_sSongGroupBannerPaths[i];
 	}
 
-	return "";
+	return NULL;
 }
 
 void SongManager::GetSongGroupNames( CStringArray &AddTo )
@@ -385,7 +385,7 @@ CString SongManager::GetCourseGroupBannerPath( const CString &sCourseGroup )
 	if( iter == m_mapCourseGroupToInfo.end() )
 	{
 		ASSERT_M( 0, ssprintf("requested banner for course group '%s' that doesn't exist",sCourseGroup.c_str()) );
-		return "";
+		return NULL;
 	}
 	else 
 	{
@@ -1439,7 +1439,7 @@ CString GetCurrentSongDisplayTitle()
 {
 	const Song* pSong = GAMESTATE->m_pCurSong;
 	if( pSong == NULL )
-		return "";
+		return NULL;
 	return pSong->GetDisplayFullTitle();
 }
 
@@ -1447,7 +1447,7 @@ CString GetCurrentSongDisplayArtist()
 {
 	const Song* pSong = GAMESTATE->m_pCurSong;
 	if( pSong == NULL )
-		return "";
+		return NULL;
 	return pSong->GetDisplayArtist();
 }
 
@@ -1455,7 +1455,7 @@ CString GetCurrentSongCredit()
 {
 	const Song* pSong = GAMESTATE->m_pCurSong;
 	if( pSong == NULL )
-		return "";
+		return NULL;
 	return pSong->m_sCredit;
 }
 
@@ -1463,7 +1463,7 @@ CString GetCurrentStepsCredits()
 {
 	const Song* pSong = GAMESTATE->m_pCurSong;
 	if( pSong == NULL )
-		return "";
+		return NULL;
 
 	CString s;
 

stepmania/src/SongUtil.cpp

@@ -212,12 +212,12 @@ void SongUtil::SortSongPointerArrayByNumPlays( vector<Song*> &vpSongsInOut, cons
 CString SongUtil::GetSectionNameFromSongAndSort( const Song* pSong, SortOrder so )
 {
 	if( pSong == NULL )
-		return "";
+		return NULL;
 
 	switch( so )
 	{
 	case SORT_PREFERRED:
-		return "";
+		return NULL;
 	case SORT_GROUP:
 		// guaranteed not empty	
 		return pSong->m_sGroupName;
@@ -234,7 +234,7 @@ CString SongUtil::GetSectionNameFromSongAndSort( const Song* pSong, SortOrder so
 			s = MakeSortString(s);	// resulting string will be uppercase
 			
 			if( s.empty() )
-				return "";
+				return NULL;
 			else if( s[0] >= '0' && s[0] <= '9' )
 				return "NUM";
 			else if( s[0] < 'A' || s[0] > 'Z')
@@ -256,7 +256,7 @@ CString SongUtil::GetSectionNameFromSongAndSort( const Song* pSong, SortOrder so
 			return ssprintf("%03d-%03d",iMaxBPM-(iBPMGroupSize-1), iMaxBPM);
 		}
 	case SORT_POPULARITY:
-		return "";
+		return NULL;
 	case SORT_TOP_GRADES:
 		{
 			int iCounts[NUM_Grade];
@@ -299,14 +299,14 @@ CString SongUtil::GetSectionNameFromSongAndSort( const Song* pSong, SortOrder so
 			return "N/A";
 		}
 	case SORT_MODE_MENU:
-		return "";
+		return NULL;
 	case SORT_ALL_COURSES:
 	case SORT_NONSTOP_COURSES:
 	case SORT_ONI_COURSES:
 	case SORT_ENDLESS_COURSES:
 	default:
 		ASSERT(0);
-		return "";
+		return NULL;
 	}
 }
 

stepmania/src/Sprite.cpp

@@ -721,7 +721,7 @@ void Sprite::SetSecondsIntoAnimation( float fSeconds )
 CString	Sprite::GetTexturePath() const
 {
 	if( m_pTexture==NULL )
-		return "";
+		return NULL;
 
 	return m_pTexture->GetID().filename;
 }

stepmania/src/StepMania.cpp

@@ -1236,7 +1236,7 @@ CString SaveScreenshot( CString sDir, bool bSaveCompressed, bool bMakeSignature,
 	if( !bResult )
 	{
 		SCREENMAN->PlayInvalidSound();
-		return "";
+		return NULL;
 	}
 
 	SCREENMAN->PlayScreenshotSound();

stepmania/src/StepMania.h

@@ -18,7 +18,7 @@ void ChangeCurrentGame( const Game* g );
 void FocusChanged( bool bHasFocus );
 bool AppHasFocus();
 
-// If successful, return filename of screenshot in sDir, else return ""
+// If successful, return filename of screenshot in sDir, else return NULL
 CString SaveScreenshot( CString sDir, bool bSaveCompressed, bool bMakeSignature, int iIndex = -1 );
 
 void InsertCoin( int iNum = 1, const RageTimer *pTime = NULL );