Files
itgmania212121/stepmania/src/SongCacheIndex.cpp
T
2006-04-30 06:00:15 +00:00

133 lines
4.4 KiB
C++

#include "global.h"
#include "SongCacheIndex.h"
#include "RageLog.h"
#include "RageUtil.h"
#include "RageFileManager.h"
#include "song.h"
#include "SpecialFiles.h"
/*
* A quick explanation of song cache hashes: Each song has two hashes; a hash of the
* song path, and a hash of the song directory. The former is Song::GetCacheFilePath;
* it stays the same if the contents of the directory change. The latter is
* GetHashForDirectory(m_sSongDir), and changes on each modification.
*
* The file hash is used as the cache filename. We don't want to use the directory
* hash: if we do that, then we'll write a new cache file every time the song changes,
* and they'll accumulate or we'll have to be careful to delete them.
*
* The directory hash is stored in here, indexed by the song path, and used to determine
* if a song has changed.
*
* Another advantage of this system is that we can load songs from cache given only their
* path; we don't have to actually look in the directory (to find out the directory hash)
* in order to find the cache file.
*/
#define CACHE_INDEX SpecialFiles::CACHE_DIR + "index.cache"
SongCacheIndex *SONGINDEX;
RString SongCacheIndex::GetCacheFilePath( const RString &sGroup, const RString &sPath )
{
/* Don't use GetHashForFile, since we don't want to spend time
* checking the file size and date. */
RString s = sPath;
s.Replace( '/', '_' );
return ssprintf( "%s/%s/%s", SpecialFiles::CACHE_DIR.c_str(), sGroup.c_str(), s.c_str() );
}
SongCacheIndex::SongCacheIndex()
{
ReadCacheIndex();
}
SongCacheIndex::~SongCacheIndex()
{
}
static void EmptyDir( RString dir )
{
ASSERT(dir[dir.size()-1] == '/');
vector<RString> asCacheFileNames;
GetDirListing( dir, asCacheFileNames );
for( unsigned i=0; i<asCacheFileNames.size(); i++ )
{
if( !IsADirectory(dir + asCacheFileNames[i]) )
FILEMAN->Remove( dir + asCacheFileNames[i] );
}
}
void SongCacheIndex::ReadCacheIndex()
{
CacheIndex.ReadFile( CACHE_INDEX ); // don't care if this fails
int iCacheVersion = -1;
CacheIndex.GetValue( "Cache", "CacheVersion", iCacheVersion );
if( iCacheVersion == FILE_CACHE_VERSION )
return; /* OK */
LOG->Trace( "Cache format is out of date. Deleting all cache files." );
EmptyDir( SpecialFiles::CACHE_DIR );
EmptyDir( SpecialFiles::CACHE_DIR+"Banners/" );
EmptyDir( SpecialFiles::CACHE_DIR+"Songs/" );
EmptyDir( SpecialFiles::CACHE_DIR+"Courses/" );
CacheIndex.Clear();
}
void SongCacheIndex::AddCacheIndex(const RString &path, unsigned hash)
{
if( hash == 0 )
++hash; /* no 0 hash values */
CacheIndex.SetValue( "Cache", "CacheVersion", FILE_CACHE_VERSION );
CacheIndex.SetValue( "Cache", MangleName(path), hash );
CacheIndex.WriteFile( CACHE_INDEX );
}
unsigned SongCacheIndex::GetCacheHash( const RString &path ) const
{
unsigned iDirHash;
if( !CacheIndex.GetValue( "Cache", MangleName(path), iDirHash ) )
return 0;
if( iDirHash == 0 )
++iDirHash; /* no 0 hash values */
return iDirHash;
}
RString SongCacheIndex::MangleName( const RString &Name )
{
/* We store paths in an INI. We can't store '='. */
RString ret = Name;
ret.Replace( "=", "");
return ret;
}
/*
* (c) 2002-2003 Glenn Maynard
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, and/or sell copies of the Software, and to permit persons to
* whom the Software is furnished to do so, provided that the above
* copyright notice(s) and this permission notice appear in all copies of
* the Software and that both the above copyright notice(s) and this
* permission notice appear in supporting documentation.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF
* THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS
* INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL 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.
*/