#i122208# replace the binaryurp cache for improved C++ compatibility

Failing to instantiatie incomplete types like the Map::iterator in
binaryurp Cache's Entry members is allowed by the C++ standard.
The rewrite makes it more compliant with other C++ compilers/STLs.
And interesting alternative would be to use boost's multi_index_container.

git-svn-id: http://svn.apache.org/repos/asf/openoffice/branches/rejuvenate01@1480367 13f79535-47bb-0310-9956-ffa450edef68

3 files changed, 79 insertions, 81 deletions

diff --git a/binaryurp/source/cache.hxx b/binaryurp/source/cache.hxx
index 05c0069a41f7..7e5ba899cc92 100644
--- a/binaryurp/source/cache.hxx
+++ b/binaryurp/source/cache.hxx
@@ -25,6 +25,7 @@
 #include <cassert>
 #include <cstddef>
 #include <map>
+#include <list>
 
 #include "boost/noncopyable.hpp"
 #include "sal/types.h"
@@ -37,88 +38,57 @@ enum { size = 256, ignore = 0xFFFF };
 
 }
 
-template< typename T > class Cache: private boost::noncopyable {
+template< typename T > class Cache : private boost::noncopyable {
 public:
+    typedef sal_uInt16 IdxType;
+
     explicit Cache(std::size_t size):
-        size_(size), first_(map_.end()), last_(map_.end())
+        size_(size)
     {
         assert(size < cache::ignore);
     }
 
-    sal_uInt16 add(T const & content, bool * found) {
-        assert(found != 0);
-        typename Map::iterator i(map_.find(content));
-        *found = i != map_.end();
-        if (i == map_.end()) {
-            typename Map::size_type n = map_.size();
-            if (n < size_) {
-                i =
-                    (map_.insert(
-                        typename Map::value_type(
-                            content,
-                            Entry(
-                                static_cast< sal_uInt16 >(n), map_.end(),
-                                first_)))).
-                    first;
-                if (first_ == map_.end()) {
-                    last_ = i;
-                } else {
-                    first_->second.prev = i;
-                }
-                first_ = i;
-            } else if (last_ != map_.end()) {
-                i =
-                    (map_.insert(
-                        typename Map::value_type(
-                            content,
-                            Entry(last_->second.index, map_.end(), first_)))).
-                    first;
-                first_->second.prev = i;
-                first_ = i;
-                typename Map::iterator j(last_);
-                last_ = last_->second.prev;
-                last_->second.next = map_.end();
-                map_.erase(j);
-            } else {
-                // Reached iff size_ == 0:
-                return cache::ignore;
-            }
-        } else if (i != first_) {
-            // Move to front (reached only if size_ > 1):
-            i->second.prev->second.next = i->second.next;
-            if (i->second.next == map_.end()) {
-                last_ = i->second.prev;
-            } else {
-                i->second.next->second.prev = i->second.prev;
-            }
-            i->second.prev = map_.end();
-            i->second.next = first_;
-            first_->second.prev = i;
-            first_ = i;
-        }
-        return i->second.index;
+    IdxType add( const T& rContent, bool* pbFound) {
+	assert( pbFound != NULL);
+	if( !size_) {
+		*pbFound = false;
+		return cache::ignore;
+	}
+	// try to insert into the map
+	list_.push_front( rContent); // create a temp entry
+	typedef std::pair<typename LruList::iterator, IdxType> MappedType;
+	typedef std::pair<typename LruItMap::iterator,bool> MapPair;
+	MapPair aMP = map_.insert( MappedType( list_.begin(), 0));
+	*pbFound = !aMP.second;
+	
+	if( !aMP.second) { // insertion not needed => found the entry
+		list_.pop_front(); // remove the temp entry
+		list_.splice( list_.begin(), list_, aMP.first->first); // the found entry is moved to front
+		return aMP.first->second;
+	}
+
+	// test insertion successful => it was new so we keep it
+	IdxType n = static_cast<IdxType>( map_.size() - 1);
+	if( n >= size_) { // cache full => replace the LRU entry
+		// find the least recently used element in the map
+		typename LruItMap::iterator it = map_.find( --list_.end());
+		n = it->second;
+		map_.erase( it); // remove it from the map
+		list_.pop_back(); // remove from the list
+	}
+	aMP.first->second = n;
+	return n;
     }
 
 private:
-    struct Entry;
-
-    typedef std::map< T, Entry > Map;
-
-    struct Entry {
-        sal_uInt16 index;
-        typename Map::iterator prev;
-        typename Map::iterator next;
-
-        Entry(
-            sal_uInt16 theIndex, typename Map::iterator thePrev,
-            typename Map::iterator theNext):
-            index(theIndex), prev(thePrev), next(theNext) {}
-    };
+    typedef std::list<T> LruList; // last recently used list
+    typedef typename LruList::iterator LruListIt;
+    struct CmpT{ bool operator()( const LruListIt& rA, const LruListIt& rB) const { return (*rA<*rB);}};
+    typedef ::std::map< LruListIt, IdxType, CmpT > LruItMap; // a map into a LruList
 
     std::size_t size_;
-    Map map_;
-    typename Map::iterator first_;
-    typename Map::iterator last_;
+    LruItMap map_;
+    LruList list_;
 };
 
 }
diff --git a/binaryurp/source/lessoperators.cxx b/binaryurp/source/lessoperators.cxx
index b0031e716815..55f3a49c2340 100644
--- a/binaryurp/source/lessoperators.cxx
+++ b/binaryurp/source/lessoperators.cxx
@@ -32,14 +32,38 @@
 
 namespace com { namespace sun { namespace star { namespace uno {
 
-bool operator <(TypeDescription const & left, TypeDescription const & right) {
-    assert(left.is() && right.is());
-    typelib_TypeClass tc1 = left.get()->eTypeClass;
-    typelib_TypeClass tc2 = right.get()->eTypeClass;
-    return tc1 < tc2 ||
-        (tc1 == tc2 &&
-         (OUString(left.get()->pTypeName) <
-          OUString(right.get()->pTypeName)));
+bool operator<( const TypeDescription& rLeft, const TypeDescription& rRight) {
+	assert( rLeft.is() && rRight.is());
+	const typelib_TypeDescription& rA = *rLeft.get();
+	const typelib_TypeDescription& rB = *rRight.get();
+	if( rA.eTypeClass != rA.eTypeClass)
+		return (rA.eTypeClass < rB.eTypeClass);
+	const sal_Int32 nCmp = rtl_ustr_compare_WithLength(
+			rA.pTypeName->buffer, rA.pTypeName->length,
+			rB.pTypeName->buffer, rB.pTypeName->length);
+	return (nCmp < 0);
+}
+
+bool TypeDescEqual::operator()( const TypeDescription& rLeft, const TypeDescription& rRight) const
+{
+	assert( rLeft.is() && rRight.is());
+	const typelib_TypeDescription& rA = *rLeft.get();
+	const typelib_TypeDescription& rB = *rRight.get();
+	if( rA.eTypeClass != rB.eTypeClass)
+		return false;
+	const sal_Int32 nCmp = rtl_ustr_compare_WithLength(
+			rA.pTypeName->buffer, rA.pTypeName->length,
+			rB.pTypeName->buffer, rB.pTypeName->length);
+	return (nCmp == 0);
+}
+
+sal_Int32 TypeDescHash::operator()( const TypeDescription& rTD) const
+{
+	assert( rTD.is());
+	const typelib_TypeDescription& rA = *rTD.get();
+	sal_Int32 h = rtl_ustr_hashCode_WithLength( rA.pTypeName->buffer, rA.pTypeName->length);
+	h ^= static_cast<sal_Int32>(rA.eTypeClass);
+	return h;
 }
 
 } } } }
@@ -47,8 +71,8 @@ bool operator <(TypeDescription const & left, TypeDescription const & right) {
 namespace rtl {
 
 bool operator <(ByteSequence const & left, ByteSequence const & right) {
-    for (sal_Int32 i = 0; i != std::min(left.getLength(), right.getLength());
-         ++i)
+    const sal_Int32 nLen = std::min( left.getLength(), right.getLength());
+    for( sal_Int32 i = 0; i < nLen; ++i )
     {
         if (left[i] < right[i]) {
             return true;
diff --git a/binaryurp/source/lessoperators.hxx b/binaryurp/source/lessoperators.hxx
index f3202b5fb5af..317e76ab18d5 100644
--- a/binaryurp/source/lessoperators.hxx
+++ b/binaryurp/source/lessoperators.hxx
@@ -31,6 +31,10 @@ namespace com { namespace sun { namespace star { namespace uno {
 
 bool operator <(TypeDescription const & left, TypeDescription const & right);
 
+struct TypeDescHash { sal_Int32 operator()( const TypeDescription&) const; };
+
+struct TypeDescEqual { bool operator()( const TypeDescription&, const TypeDescription&) const; };
+
 } } } }
 
 namespace rtl {