1 files changed, 417 insertions, 0 deletions
diff --git a/sal/rtl/source/unload.cxx b/sal/rtl/source/unload.cxx
new file mode 100644
index 000000000000..ba31bd9c86f9
--- /dev/null
+++ b/sal/rtl/source/unload.cxx
@@ -0,0 +1,417 @@
+/*************************************************************************
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * Copyright 2000, 2010 Oracle and/or its affiliates.
+ *
+ * OpenOffice.org - a multi-platform office productivity suite
+ *
+ * This file is part of OpenOffice.org.
+ *
+ * OpenOffice.org is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 3
+ * only, as published by the Free Software Foundation.
+ *
+ * OpenOffice.org is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License version 3 for more details
+ * (a copy is included in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * version 3 along with OpenOffice.org.  If not, see
+ * <http://www.openoffice.org/license.html>
+ * for a copy of the LGPLv3 License.
+ *
+ ************************************************************************/
+
+// MARKER(update_precomp.py): autogen include statement, do not remove
+#include "precompiled_sal.hxx"
+#include <rtl/unload.h>
+#include <rtl/alloc.h>
+#include <rtl/ustring.hxx>
+#include <osl/mutex.hxx>
+#include <hash_map>
+#include "rtl/allocator.hxx"
+
+#include <functional>
+#include <list>
+#include <deque>
+
+using osl::MutexGuard;
+
+//----------------------------------------------------------------------------
+
+static void rtl_notifyUnloadingListeners();
+
+static sal_Bool isEqualTimeValue ( const TimeValue* time1,  const TimeValue* time2)
+{
+    if( time1->Seconds == time2->Seconds &&
+        time1->Nanosec == time2->Nanosec)
+        return sal_True;
+    else
+        return sal_False;
+}
+
+static sal_Bool isGreaterTimeValue(  const TimeValue* time1,  const TimeValue* time2)
+{
+    sal_Bool retval= sal_False;
+    if ( time1->Seconds > time2->Seconds)
+        retval= sal_True;
+    else if ( time1->Seconds == time2->Seconds)
+    {
+        if( time1->Nanosec > time2->Nanosec)
+            retval= sal_True;
+    }
+    return retval;
+}
+
+static sal_Bool isGreaterEqualTimeValue( const TimeValue* time1, const TimeValue* time2)
+{
+    if( isEqualTimeValue( time1, time2) )
+        return sal_True;
+    else if( isGreaterTimeValue( time1, time2))
+        return sal_True;
+    else
+        return sal_False;
+}
+
+static void addTimeValue( const TimeValue* value1, const TimeValue* value2, TimeValue* result)
+{
+    sal_uInt64 sum;
+    result->Nanosec=0;
+    result->Seconds=0;
+
+    sum= value1->Nanosec + value2->Nanosec;
+    if( sum >= 1000000000 )
+    {
+        result->Seconds=1;
+        sum -= 1000000000;
+    }
+    result->Nanosec= (sal_uInt32)sum;
+    result->Seconds += value1->Seconds + value2->Seconds;
+}
+
+
+static sal_Bool hasEnoughTimePassed( const TimeValue* unusedSince, const TimeValue* timespan)
+{
+    sal_Bool retval= sal_False;
+    TimeValue currentTime;
+    if( osl_getSystemTime( &currentTime))
+    {
+        TimeValue addedTime;
+        addTimeValue( unusedSince, timespan, &addedTime);
+        if( isGreaterEqualTimeValue( &currentTime, &addedTime))
+            retval= sal_True;
+    }
+
+    return retval;
+}
+
+static osl::Mutex* getUnloadingMutex()
+{
+    static osl::Mutex * g_pMutex= NULL;
+    if (!g_pMutex)
+    {
+        MutexGuard guard( osl::Mutex::getGlobalMutex() );
+        if (!g_pMutex)
+        {
+            static osl::Mutex g_aMutex;
+            g_pMutex= &g_aMutex;
+        }
+    }
+    return g_pMutex;
+}
+
+extern "C" void rtl_moduleCount_acquire(rtl_ModuleCount * that )
+{
+    rtl_StandardModuleCount* pMod= (rtl_StandardModuleCount*)that;
+    osl_incrementInterlockedCount( &pMod->counter);
+}
+
+extern "C" void rtl_moduleCount_release( rtl_ModuleCount * that )
+{
+    rtl_StandardModuleCount* pMod= (rtl_StandardModuleCount*)that;
+    OSL_ENSURE( pMod->counter >0 , "library counter incorrect" );
+    osl_decrementInterlockedCount( &pMod->counter);
+    if( pMod->counter == 0)
+    {
+        MutexGuard guard( getUnloadingMutex());
+
+        if( sal_False == osl_getSystemTime( &pMod->unusedSince) )
+        {
+            // set the time to 0 if we could not get the time
+            pMod->unusedSince.Seconds= 0;
+            pMod->unusedSince.Nanosec= 0;
+        }
+    }
+}
+
+
+struct hashModule
+{
+    size_t operator()( const oslModule& rkey) const
+    {
+        return (size_t)rkey;
+    }
+};
+
+typedef std::hash_map<
+    oslModule,
+    std::pair<sal_uInt32, component_canUnloadFunc>,
+    hashModule,
+    std::equal_to<oslModule>,
+    rtl::Allocator<oslModule>
+> ModuleMap;
+
+typedef ModuleMap::iterator Mod_IT;
+
+static ModuleMap& getModuleMap()
+{
+    static ModuleMap * g_pMap= NULL;
+    if (!g_pMap)
+    {
+        MutexGuard guard( getUnloadingMutex() );
+        if (!g_pMap)
+        {
+            static ModuleMap g_aModuleMap;
+            g_pMap= &g_aModuleMap;
+        }
+    }
+    return *g_pMap;
+}
+
+extern "C" sal_Bool rtl_moduleCount_canUnload( rtl_StandardModuleCount * that, TimeValue * libUnused)
+{
+    if (that->counter == 0)
+    {
+        MutexGuard guard( getUnloadingMutex());
+        if (libUnused && (that->counter == 0))
+        {
+            rtl_copyMemory(libUnused, &that->unusedSince, sizeof(TimeValue));
+        }
+    }
+    return (that->counter == 0);
+}
+
+
+extern "C" sal_Bool SAL_CALL rtl_registerModuleForUnloading( oslModule module)
+{
+    MutexGuard guard( getUnloadingMutex());
+    ModuleMap& moduleMap= getModuleMap();
+    sal_Bool ret= sal_True;
+
+    // If the module has been registered before, then find it and increment
+    // its reference cout
+    Mod_IT it= moduleMap.find( module);
+    if( it != moduleMap.end())
+    {
+        //module already registered, increment ref count
+        it->second.first++;
+    }
+    else
+    {
+        // Test if the module supports unloading (exports component_canUnload)
+        rtl::OUString name(RTL_CONSTASCII_USTRINGPARAM( COMPONENT_CANUNLOAD));
+        component_canUnloadFunc pFunc=
+            (component_canUnloadFunc)osl_getFunctionSymbol( module, name.pData);
+        if (pFunc)
+        {
+            //register module for the first time, set ref count to 1
+            moduleMap[module]= std::make_pair((sal_uInt32)1, pFunc);
+        }
+        else
+            ret= sal_False;
+    }
+    return ret;
+}
+
+extern "C" void SAL_CALL rtl_unregisterModuleForUnloading( oslModule module)
+{
+    MutexGuard guard( getUnloadingMutex());
+
+    ModuleMap& moduleMap= getModuleMap();
+    Mod_IT it= moduleMap.find( module);
+    if( it != moduleMap.end() )
+    {
+        // The module is registered, decrement ref count.
+        it->second.first --;
+
+        // If the refcount == 0 then remove the module from the map
+        if( it->second.first == 0)
+            moduleMap.erase( it);
+    }
+}
+
+extern "C" void SAL_CALL rtl_unloadUnusedModules( TimeValue* libUnused)
+{
+    MutexGuard guard( getUnloadingMutex());
+
+    typedef std::list< oslModule, rtl::Allocator<oslModule> > list_type;
+    list_type unloadedModulesList;
+
+    ModuleMap& moduleMap= getModuleMap();
+    Mod_IT it_e= moduleMap.end();
+
+    // notify all listeners
+    rtl_notifyUnloadingListeners();
+
+    // prepare default TimeValue if argumetn is NULL
+    TimeValue nullTime={0,0};
+    TimeValue* pLibUnused= libUnused? libUnused : &nullTime;
+
+    Mod_IT it= moduleMap.begin();
+    for (; it != it_e; ++it)
+    {
+        //can the module be unloaded?
+        component_canUnloadFunc func= it->second.second;
+        TimeValue unusedSince= {0, 0};
+
+        if( func( &unusedSince) )
+        {
+            // module can be unloaded if it has not been used at least for the time
+            // specified by the argument libUnused
+            if( hasEnoughTimePassed( &unusedSince, pLibUnused))
+            {
+                // get the reference count and unload the module as many times
+                sal_uInt32 refCount= it->second.first;
+
+                for ( sal_uInt32 i=0; i < refCount; i++)
+                    osl_unloadModule( it->first);
+
+                // mark the module for later removal
+                unloadedModulesList.push_front( it->first);
+            }
+        }
+    }
+
+    // remove all entries containing invalid (unloaded) modules
+    list_type::const_iterator un_it= unloadedModulesList.begin();
+    for (; un_it != unloadedModulesList.end(); ++un_it)
+    {
+        moduleMap.erase( *un_it);
+    }
+}
+
+
+// ==============================================================================
+// Unloading Listener Administration
+//===============================================================================
+struct hashListener
+{
+    size_t operator()( const sal_Int32& rkey) const
+    {
+        return (size_t)rkey;
+    }
+};
+
+typedef std::hash_map<
+    sal_Int32,
+    std::pair<rtl_unloadingListenerFunc, void*>,
+    hashListener,
+    std::equal_to<sal_Int32>,
+    rtl::Allocator<sal_Int32>
+> ListenerMap;
+
+typedef ListenerMap::iterator Lis_IT;
+
+static ListenerMap& getListenerMap()
+{
+    static ListenerMap * g_pListeners= NULL;
+    if (!g_pListeners)
+    {
+        MutexGuard guard( getUnloadingMutex() );
+        if (!g_pListeners)
+        {
+            static ListenerMap g_aListenerMap;
+            g_pListeners= &g_aListenerMap;
+        }
+    }
+    return *g_pListeners;
+}
+
+
+// This queue contains cookies which have been passed out by rtl_addUnloadingListener and
+// which have been regainded by rtl_removeUnloadingListener. When rtl_addUnloadingListener
+// is called then a cookie has to be returned. First we look into the set if there is one
+// availabe. Otherwise a new cookie will be provided.
+// not a new value is returned.
+
+typedef std::deque<
+    sal_Int32,
+    rtl::Allocator<sal_Int32>
+> queue_type;
+
+static queue_type& getCookieQueue()
+{
+    static queue_type * g_pCookies= NULL;
+    if (!g_pCookies)
+    {
+        MutexGuard guard( getUnloadingMutex() );
+        if (!g_pCookies)
+        {
+            static queue_type g_aCookieQueue;
+            g_pCookies= &g_aCookieQueue;
+        }
+    }
+    return *g_pCookies;
+}
+
+static sal_Int32 getCookie()
+{
+    static sal_Int32 cookieValue= 1;
+
+    sal_Int32 retval;
+    queue_type& regainedCookies= getCookieQueue();
+    if( regainedCookies.empty() )
+        retval= cookieValue++;
+    else
+    {
+        retval= regainedCookies.front();
+        regainedCookies.pop_front();
+    }
+    return retval;
+}
+
+static inline void recycleCookie( sal_Int32 i)
+{
+    getCookieQueue().push_back(i);
+}
+
+
+// calling the function twice with the same arguments will return tow different cookies.
+// The listener will then notified twice.
+
+extern "C"
+sal_Int32 SAL_CALL rtl_addUnloadingListener( rtl_unloadingListenerFunc callback, void* _this)
+{
+    MutexGuard guard( getUnloadingMutex());
+
+    sal_Int32 cookie= getCookie();
+    ListenerMap& listenerMap= getListenerMap();
+    listenerMap[ cookie]= std::make_pair( callback, _this);
+    return cookie;
+}
+
+
+extern "C"
+void SAL_CALL rtl_removeUnloadingListener( sal_Int32 cookie )
+{
+    MutexGuard guard( getUnloadingMutex());
+
+    ListenerMap& listenerMap= getListenerMap();
+    size_t removedElements= listenerMap.erase( cookie);
+    if( removedElements )
+        recycleCookie( cookie);
+}
+
+
+static void rtl_notifyUnloadingListeners()
+{
+    ListenerMap& listenerMap= getListenerMap();
+    for( Lis_IT it= listenerMap.begin(); it != listenerMap.end(); ++it)
+    {
+        rtl_unloadingListenerFunc callbackFunc= it->second.first;
+        callbackFunc( it->second.second);
+    }
+}