- some optimisations

- added dropping items out of cache

3 files changed, 57 insertions, 26 deletions

diff --git a/cache.h b/cache.h
index b34c1c2..0b81cf5 100755
--- a/cache.h
+++ b/cache.h
@@ -1,6 +1,7 @@
 #ifndef VGSTOOLS_CACHE_H
 #define VGSTOOLS_CACHE_H
 
+#include <cassert>
 #include <algorithm>
 #include <ctime>
 #include <list>
@@ -22,22 +23,24 @@ class cache
 {
 public:
 	typedef TKey key_type;
-	typedef TValue value_type;
-	typedef std::tr1::shared_ptr< value_type > ptr_type;
+	typedef TValue mapped_type;
+	typedef std::tr1::shared_ptr< mapped_type > ptr_type;
 
 private:
-	struct Value
+	/*struct Value
 	{
-		ptr_type value;
-		std::time_t creation;
+		key_type key_;
+		ptr_type value_;
 
-		Value( key_type const& key )
-			: value( new value_type( key ) )
-			, creation( 0 ) {}
-	};
+		Value( key_type const& key, ptr_type const& value )
+			: key_( key )
+			, value_( value ) {}
+	};*/
 
-	typedef std::list< Value > ValueList;
-	typedef std::map< TKey, typename ValueList::iterator > KeyMap;
+	typedef std::pair< key_type, ptr_type > value_type;
+
+	typedef std::list< value_type > ValueList;
+	typedef std::map< key_type, typename ValueList::iterator > KeyMap;
 
 public:
 	cache( size_t maxWeight )
@@ -49,6 +52,43 @@ public:
 
 	ptr_type get( key_type const& key )
 	{
+		assert( m_lookup.size() == m_values.size() );
+
+		typename KeyMap::iterator it = m_lookup.find( key );
+		ptr_type result = it != m_lookup.end() ? it->second->second : ptr_type( new mapped_type( key ) );
+
+		if ( it != m_lookup.end() ) {
+			if ( result->is_current() ) {
+				if ( it->second != m_values.begin() ) {
+					m_values.erase( it->second );
+					it->second = m_values.insert( m_values.begin(), std::make_pair( key, result ) );
+				}
+				return result;
+			}
+
+			m_currentWeight -= result->weight();
+			m_values.erase( it->second );
+			m_lookup.erase( it );
+		}
+
+		if ( !result->load() )
+			return ptr_type();
+
+		// put new object into cache
+		if ( result->weight() < m_maxWeight ) {
+			m_currentWeight += result->weight();
+			m_lookup.insert( std::make_pair( key, m_values.insert( m_values.begin(), std::make_pair( key, result ) ) ) );
+			while ( m_currentWeight > m_maxWeight ) {
+				value_type& value = m_values.back();
+				m_currentWeight -= value.second->weight();
+				m_lookup.erase( m_lookup.find( value.first ) );
+				m_values.pop_back();
+			}
+		}
+
+		return result;
+#if 0	
+		
 		typename KeyMap::iterator it = m_lookup.find( key );
 		if ( it == m_lookup.end() ) {
 			typename ValueList::iterator element = m_values.insert( m_values.begin(), Value( key ) );
@@ -75,6 +115,7 @@ public:
 			value = &*element;
 		}
 		return value->value;
+#endif
 	}
 
 private:
diff --git a/filecache.cpp b/filecache.cpp
index 9a21647..37a1e85 100644
--- a/filecache.cpp
+++ b/filecache.cpp
@@ -10,22 +10,10 @@ std::time_t FileObject::get_filetime( std::string const& path )
 {
 	struct stat sbuf;
 	if ( stat( path.c_str(), &sbuf ) < 0 )
-		return 0; // XXX
+		return 0;
 	return sbuf.st_ctime;
 }
 
-bool FileObject::is_current() const
-{
-	return m_ctime < get_filetime( m_path );
-	/*struct stat statBuf = { 0 };
- * 	if ( ::stat( m_path.c_str(), &statBuf ) < 0 ) {
- * 		}
-	if ( m_ctime == 0 )
-		return true;
-	m_ctime = get_filetime( m_path );
-	return timestamp < m_ctime;*/
-}
-
 bool FileObject::load()
 {
 	std::ifstream ifs( m_path.c_str(), std::ios::in | std::ios::binary | std::ios::ate );
diff --git a/filecache.h b/filecache.h
index 0556616..89d884f 100644
--- a/filecache.h
+++ b/filecache.h
@@ -1,6 +1,7 @@
 #ifndef VDR_LIVE_FILECACHE_H
 #define VDR_LIVE_FILECACHE_H
 
+#include <numeric>
 #include <string>
 #include <vector>
 #include <vdr/tools.h>
@@ -12,12 +13,12 @@ class FileObject
 {
 public:
 	FileObject( std::string const& path )
-		: m_ctime( 0 )
+		: m_ctime( std::numeric_limits< std::time_t >::max()  )
 		, m_path( path ) {}
 
 	std::size_t size() const { return m_data.size(); }
 	std::size_t weight() const { return size(); }
-	bool is_current() const;
+	bool is_current() const { return m_ctime == get_filetime( m_path ); }
 	bool load();
 	char const* data() const { return &m_data[0]; }
 	std::time_t ctime() const { return m_ctime; }
@@ -33,6 +34,7 @@ private:
 class FileCache: public vgstools::cache< std::string, FileObject >
 {
 	typedef vgstools::cache< std::string, FileObject > base_type;
+
 public:
 	FileCache( size_t maxWeight ): base_type( maxWeight ) {}