1 files changed, 150 insertions, 0 deletions

diff --git a/src/unstable/myriadcache.h b/src/unstable/myriadcache.h
new file mode 100644
index 0000000..d6842a5
--- /dev/null
+++ b/src/unstable/myriadcache.h
@@ -0,0 +1,150 @@
+/*
+ * Copyright (C) 2007-2023 Xagasoft, All rights reserved.
+ *
+ * This file is part of the libbu++ library and is released under the
+ * terms of the license contained in the file LICENSE.
+ */
+
+#ifndef BU_MYRIAD_CACHE_H
+#define BU_MYRIAD_CACHE_H
+
+#include "bu/cachebase.h"
+#include "bu/myriad.h"
+#include "bu/myriadstream.h"
+#include "bu/file.h"
+#include "bu/streamstack.h"
+
+namespace Bu
+{
+    template<typename keytype, typename obtype>
+    class MyriadCache : public Bu::CacheBase<keytype, obtype>
+    {
+    public:
+        MyriadCache( Bu::Stream &sStore, int iBlockSize=512, int iPreallocate=8 ) :
+            sStore( sStore ),
+            mStore( sStore, iBlockSize, iPreallocate ),
+            bStructureChanged( false )
+        {
+            try
+            {
+                Bu::ReadWriteMutex::ReadLocker l( rwStore );
+                Bu::MyriadStream ms = mStore.open(
+                    1, Bu::Myriad::WriteNew|Bu::Myriad::Read
+                    );
+                Bu::Archive ar( ms, Bu::Archive::load );
+                uint8_t uVer;
+                ar >> uVer;
+                switch( uVer )
+                {
+                    case 0:
+                        ar >> hIndex;
+                        break;
+                }
+            }
+            catch(...)
+            {
+                try
+                {
+                    mStore.open( 1, Bu::Myriad::Create|Bu::Myriad::ReadWrite );
+                    _sync();
+                }
+                catch(...)
+                {
+                    throw Bu::ExceptionBase("Error creating index stream.");
+                }
+            }
+        }
+
+        virtual ~MyriadCache()
+        {
+            Bu::CacheBase<keytype,obtype>::sync();
+        }
+       
+        using typename Bu::CacheBase<keytype,obtype>::KeyList;
+        using typename Bu::CacheBase<keytype,obtype>::ObjectType;
+        
+        virtual typename Bu::CacheBase<keytype,obtype>::KeyList getKeys() const
+        {
+            Bu::ReadWriteMutex::ReadLocker rl( rwStore );
+            return hIndex.getKeys();
+        }
+        
+        virtual int getSize() const
+        {
+            Bu::ReadWriteMutex::ReadLocker rl( rwStore );
+            return hIndex.getSize();
+        }
+
+    protected:
+        virtual bool _has( const keytype &key )
+        {
+            Bu::ReadWriteMutex::ReadLocker rl( rwStore );
+            return hIndex.has( key );
+        }
+
+        virtual void _create( const obtype *o )
+        {
+            Bu::ReadWriteMutex::WriteLocker wl( rwStore );
+            {
+                Bu::MyriadStream ms = mStore.create( Bu::Myriad::Create );
+                hIndex.insert( o->getKey(), ms.getId() );
+            }
+            _save( o );
+
+            bStructureChanged = true;
+        }
+
+        virtual void _erase( const keytype &k )
+        {
+            Bu::ReadWriteMutex::WriteLocker wl( rwStore );
+            mStore.erase( hIndex.get( k ) );
+            hIndex.erase( k );
+
+            bStructureChanged = true;
+        }
+
+        virtual obtype *_load(
+            typename Bu::CacheObject<keytype, obtype>::Initializer &initObj,
+            const keytype &k
+            )
+        {
+            Bu::MyriadStream ms = mStore.openStream( hIndex.get( k ) );
+            return _cacheObjectLoad<keytype, obtype>( initObj, k, ms );
+        }
+
+        virtual void _save( const obtype *o )
+        {
+            Bu::MyriadStream ms = mStore.openStream( hIndex.get( o->getKey() ) );
+            _cacheObjectSave( ms, o );
+            ms.setSize( ms.tell() );
+            
+            mStore.sync();
+        }
+
+        virtual void _sync()
+        {
+            Bu::ReadWriteMutex::WriteLocker wl( rwStore );
+            if( !bStructureChanged )
+                return;
+
+            Bu::MyriadStream ms = mStore.openStream( 1 );
+            Bu::Archive ar( ms, Bu::Archive::save );
+            ar << (uint8_t)0 << hIndex;
+            ar.close();
+            ms.setSize( ms.tell() );
+
+            bStructureChanged = false;
+
+            mStore.sync();
+        }
+
+    private:
+        Bu::Stream &sStore;
+        Bu::Myriad mStore;
+        Bu::Hash<keytype, int> hIndex;
+        mutable Bu::ReadWriteMutex rwStore;
+        bool bStructureChanged;
+    };
+}
+
+#endif