Move cache indexing into a global object. Only load the cache file once, instead of for each song loaded. (Speedup, and simplifies Song.cpp.)

It's still written over for each file; this way, if a file load crashes, the earlier files will still be written to cache.

stepmania/src/Song.cpp

@@ -20,6 +20,7 @@
 #include "MsdFile.h"
 #include "RageSoundStream.h"
 #include "RageException.h"
+#include "SongCacheIndex.h"
 
 
 const int FILE_CACHE_VERSION = 61;	// increment this when Song or Notes changes to invalidate cache
@@ -292,25 +293,7 @@ bool Song::LoadFromSongDir( CString sDir )
 	//
 	// First look in the cache for this song (without loading NoteData)
 	//
-	IniFile ini;
-	ini.SetPath( "Cache\\index.cache" );
-	if( !ini.ReadFile() )
-		goto load_without_cache;
-
-	int iCacheVersion;
-	ini.GetValueI( "Cache", "CacheVersion", iCacheVersion );
-	if( iCacheVersion != FILE_CACHE_VERSION )
-	{
-		LOG->Trace( "Cache format is out of date.  Deleting all cache files." );
-		CStringArray asCacheFileNames;
-		GetDirListing( "Cache\\*.*", asCacheFileNames );
-		for( int i=0; i<asCacheFileNames.GetSize(); i++ )
-			DeleteFile( "Cache\\" + asCacheFileNames[i] );
-		goto load_without_cache;
-	}
-
-	int iDirHash;
-	ini.GetValueI( "Cache", m_sSongDir, iDirHash );
+	int iDirHash = SONGINDEX->GetCacheHash(m_sSongDir);
 	if( GetHashForDirectory(m_sSongDir) == iDirHash )	// this cache is up to date
 	{
 		if( !DoesFileExist(GetCacheFilePath()) )
@@ -1237,16 +1220,7 @@ void Song::SaveToCacheFile()
 {
 	LOG->Trace( "Song::SaveToCacheFile()" );
 
-	//
-	// First look in the cache for this song (without loading NoteData)
-	//
-	IniFile ini;
-	ini.SetPath( "Cache\\index.cache" );
-	ini.ReadFile();	// don't care if this fails
-
-	ini.SetValueI( "Cache", "CacheVersion", FILE_CACHE_VERSION );
-	ini.SetValueI( "Cache", m_sSongDir, GetHashForDirectory(m_sSongDir) );
-	ini.WriteFile();
+	SONGINDEX->AddCacheIndex(m_sSongDir, GetHashForDirectory(m_sSongDir));
 	SaveToSMFile( GetCacheFilePath() );
 }
 

stepmania/src/SongCacheIndex.cpp

@@ -0,0 +1,48 @@
+#include "SongCacheIndex.h"
+#include "RageLog.h"
+#include "RageUtil.h"
+#include "Song.h"
+
+SongCacheIndex *SONGINDEX;
+
+SongCacheIndex::SongCacheIndex()
+{
+	CacheIndex.SetPath( "Cache\\index.cache" );
+	ReadCacheIndex();
+}
+
+SongCacheIndex::~SongCacheIndex()
+{
+
+}
+
+void SongCacheIndex::ReadCacheIndex()
+{
+	CacheIndex.ReadFile();	// don't care if this fails
+
+	int iCacheVersion;
+	CacheIndex.GetValueI( "Cache", "CacheVersion", iCacheVersion );
+	if( iCacheVersion == FILE_CACHE_VERSION )
+		return; /* OK */
+
+	LOG->Trace( "Cache format is out of date.  Deleting all cache files." );
+	CStringArray asCacheFileNames;
+	GetDirListing( "Cache/*.*", asCacheFileNames );
+	for( int i=0; i<asCacheFileNames.GetSize(); i++ )
+		DeleteFile( "Cache/" + asCacheFileNames[i] );
+	CacheIndex.Reset();
+}
+
+void SongCacheIndex::AddCacheIndex(const CString &path, int hash)
+{
+	CacheIndex.SetValueI( "Cache", "CacheVersion", FILE_CACHE_VERSION );
+	CacheIndex.SetValueI( "Cache", path, hash );
+	CacheIndex.WriteFile();
+}
+
+int SongCacheIndex::GetCacheHash( const CString &path )
+{
+	int iDirHash;
+	CacheIndex.GetValueI( "Cache", path, iDirHash );
+	return iDirHash;
+}

stepmania/src/SongCacheIndex.h

@@ -0,0 +1,20 @@
+#ifndef SONG_CACHE_INDEX_H
+#define SONG_CACHE_INDEX_H
+
+#include "stdafx.h"
+#include "IniFile.h"
+
+class SongCacheIndex {
+	IniFile CacheIndex;
+public:
+	SongCacheIndex();
+	~SongCacheIndex();
+
+	void ReadCacheIndex();
+	void AddCacheIndex( const CString &path, int hash );
+	int GetCacheHash( const CString &path );
+};
+
+extern SongCacheIndex *SONGINDEX;	// global and accessable from anywhere in our program
+
+#endif

stepmania/src/StepMania.cpp

@@ -41,6 +41,7 @@
 #include "InputFilter.h"
 #include "InputMapper.h"
 #include "InputQueue.h"
+#include "SongCacheIndex.h"
 
 //
 // StepMania common classes
@@ -666,6 +667,8 @@ HRESULT CreateObjects( HWND hWnd )
 	INPUTFILTER	= new InputFilter();
 	INPUTMAPPER	= new InputMapper();
 	INPUTQUEUE	= new InputQueue();
+	SONGINDEX	= new SongCacheIndex();
+	/* depends on SONGINDEX: */
 	SONGMAN		= new SongManager( PaintLoadingWindow );		// this takes a long time to load
 	DISPLAY		= new RageDisplay( hWnd );
 
@@ -714,6 +717,7 @@ void DestroyObjects()
 	SAFE_DELETE( INPUTMAPPER );
 	SAFE_DELETE( INPUTFILTER );
 	SAFE_DELETE( SONGMAN );
+	SAFE_DELETE( SONGINDEX );
 	SAFE_DELETE( PREFSMAN );
 	SAFE_DELETE( GAMESTATE );
 	SAFE_DELETE( GAMEMAN );

stepmania/src/StepMania.dsp

@@ -344,6 +344,14 @@ SOURCE=.\song.h
 # End Source File
 # Begin Source File
 
+SOURCE=.\SongCacheIndex.cpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\SongCacheIndex.h
+# End Source File
+# Begin Source File
+
 SOURCE=.\SongOptions.cpp
 # End Source File
 # Begin Source File

stepmania/src/song.h

@@ -15,6 +15,7 @@
 #include "GameConstantsAndTypes.h"
 #include "RageUtil.h"
 
+extern const int FILE_CACHE_VERSION;
 
 struct BPMSegment 
 {