replace double-checked locking patterns with thread safe local statics

Change-Id: I1bf67196e97411aeecc13ed4f91d1088a315e323
Reviewed-on: https://gerrit.libreoffice.org/62839
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>

4 files changed, 43 insertions, 80 deletions

diff --git a/stoc/source/invocation/invocation.cxx b/stoc/source/invocation/invocation.cxx
index 6cc658415bd6..271b90651400 100644
--- a/stoc/source/invocation/invocation.cxx
+++ b/stoc/source/invocation/invocation.cxx
@@ -970,76 +970,65 @@ void Invocation_Impl::fillInfoForMethod
 // XTypeProvider
 Sequence< Type > SAL_CALL Invocation_Impl::getTypes()
 {
-    static Sequence< Type > const * s_pTypes = nullptr;
-    if (! s_pTypes)
-    {
-        Sequence< Type > types( 4 + 10 );
-        Type * pTypes = types.getArray();
+    static Sequence<Type> s_types = [this]() {
+        Sequence<Type> types(4 + 10);
+        Type* pTypes = types.getArray();
         sal_Int32 n = 0;
 
-        pTypes[ n++ ] = cppu::UnoType<XTypeProvider>::get();
-        pTypes[ n++ ] = cppu::UnoType<XWeak>::get();
-        pTypes[ n++ ] = cppu::UnoType<XInvocation>::get();
-        pTypes[ n++ ] = cppu::UnoType<XMaterialHolder>::get();
+        pTypes[n++] = cppu::UnoType<XTypeProvider>::get();
+        pTypes[n++] = cppu::UnoType<XWeak>::get();
+        pTypes[n++] = cppu::UnoType<XInvocation>::get();
+        pTypes[n++] = cppu::UnoType<XMaterialHolder>::get();
 
         // Invocation does not support XExactName if direct object supports
         // XInvocation, but not XExactName.
-        if ((_xDirect.is() && _xENDirect.is()) ||
-            (!_xDirect.is() && _xENIntrospection.is()))
+        if ((_xDirect.is() && _xENDirect.is()) || (!_xDirect.is() && _xENIntrospection.is()))
         {
-            pTypes[ n++ ] = cppu::UnoType<XExactName>::get();
+            pTypes[n++] = cppu::UnoType<XExactName>::get();
         }
-        if( _xNameContainer.is() )
+        if (_xNameContainer.is())
         {
-            pTypes[ n++ ] = cppu::UnoType<XNameContainer>::get();
+            pTypes[n++] = cppu::UnoType<XNameContainer>::get();
         }
-        if( _xNameReplace.is() )
+        if (_xNameReplace.is())
         {
-            pTypes[ n++ ] = cppu::UnoType<XNameReplace>::get();
+            pTypes[n++] = cppu::UnoType<XNameReplace>::get();
         }
-        if( _xNameAccess.is() )
+        if (_xNameAccess.is())
         {
-            pTypes[ n++ ] = cppu::UnoType<XNameAccess>::get();
+            pTypes[n++] = cppu::UnoType<XNameAccess>::get();
         }
         if (_xIndexContainer.is())
         {
-            pTypes[ n++ ] = cppu::UnoType<XIndexContainer>::get();
+            pTypes[n++] = cppu::UnoType<XIndexContainer>::get();
         }
         if (_xIndexReplace.is())
         {
-            pTypes[ n++ ] = cppu::UnoType<XIndexReplace>::get();
+            pTypes[n++] = cppu::UnoType<XIndexReplace>::get();
         }
         if (_xIndexAccess.is())
         {
-            pTypes[ n++ ] = cppu::UnoType<XIndexAccess>::get();
+            pTypes[n++] = cppu::UnoType<XIndexAccess>::get();
         }
         if (_xEnumerationAccess.is())
         {
-            pTypes[ n++ ] = cppu::UnoType<XEnumerationAccess>::get();
+            pTypes[n++] = cppu::UnoType<XEnumerationAccess>::get();
         }
         if (_xElementAccess.is())
         {
-            pTypes[ n++ ] = cppu::UnoType<XElementAccess>::get();
+            pTypes[n++] = cppu::UnoType<XElementAccess>::get();
         }
         // Invocation does not support XInvocation2, if direct object supports
         // XInvocation, but not XInvocation2.
-        if ( ( _xDirect.is() && _xDirect2.is()) ||
-             (!_xDirect.is() && _xIntrospectionAccess.is() ) )
+        if ((_xDirect.is() && _xDirect2.is()) || (!_xDirect.is() && _xIntrospectionAccess.is()))
         {
-            pTypes[ n++ ] = cppu::UnoType<XInvocation2>::get();
+            pTypes[n++] = cppu::UnoType<XInvocation2>::get();
         }
 
-        types.realloc( n );
-
-        // store types
-        MutexGuard guard( Mutex::getGlobalMutex() );
-        if (! s_pTypes)
-        {
-            static Sequence< Type > s_types( types );
-            s_pTypes = &s_types;
-        }
-    }
-    return *s_pTypes;
+        types.realloc(n);
+        return types;
+    }();
+    return s_types;
 }
 
 Sequence< sal_Int8 > SAL_CALL Invocation_Impl::getImplementationId(  )
diff --git a/stoc/source/proxy_factory/proxyfac.cxx b/stoc/source/proxy_factory/proxyfac.cxx
index 57b0f2a05418..b85ed4907b9c 100644
--- a/stoc/source/proxy_factory/proxyfac.cxx
+++ b/stoc/source/proxy_factory/proxyfac.cxx
@@ -93,29 +93,16 @@ UnoInterfaceReference FactoryImpl::binuno_queryInterface(
     typelib_InterfaceTypeDescription * pTypeDescr )
 {
     // init queryInterface() td
-    static typelib_TypeDescription * s_pQITD = nullptr;
-    if (s_pQITD == nullptr)
-    {
-        ::osl::MutexGuard aGuard( ::osl::Mutex::getGlobalMutex() );
-        if (s_pQITD == nullptr)
-        {
-            typelib_TypeDescription * pTXInterfaceDescr = nullptr;
-            TYPELIB_DANGER_GET(
-                &pTXInterfaceDescr,
-                cppu::UnoType<XInterface>::get().getTypeLibType() );
-            typelib_TypeDescription * pQITD = nullptr;
-            typelib_typedescriptionreference_getDescription(
-                &pQITD, reinterpret_cast< typelib_InterfaceTypeDescription * >(
-                    pTXInterfaceDescr )->ppAllMembers[ 0 ] );
-            TYPELIB_DANGER_RELEASE( pTXInterfaceDescr );
-            OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER();
-            s_pQITD = pQITD;
-        }
-    }
-    else
-    {
-        OSL_DOUBLE_CHECKED_LOCKING_MEMORY_BARRIER();
-    }
+    static typelib_TypeDescription* s_pQITD = []() {
+        typelib_TypeDescription* pTXInterfaceDescr = nullptr;
+        TYPELIB_DANGER_GET(&pTXInterfaceDescr, cppu::UnoType<XInterface>::get().getTypeLibType());
+        typelib_TypeDescription* pQITD = nullptr;
+        typelib_typedescriptionreference_getDescription(
+            &pQITD, reinterpret_cast<typelib_InterfaceTypeDescription*>(pTXInterfaceDescr)
+                        ->ppAllMembers[0]);
+        TYPELIB_DANGER_RELEASE(pTXInterfaceDescr);
+        return pQITD;
+    }();
 
     void * args[ 1 ];
     args[ 0 ] = &reinterpret_cast< typelib_TypeDescription * >(
diff --git a/stoc/source/security/permissions.cxx b/stoc/source/security/permissions.cxx
index 1390275b3246..d8a4ac9b0c70 100644
--- a/stoc/source/security/permissions.cxx
+++ b/stoc/source/security/permissions.cxx
@@ -285,20 +285,12 @@ char const * FilePermission::s_actions [] = { "read", "write", "execute", "delet
 
 static OUString const & getWorkingDir()
 {
-    static OUString * s_workingDir = nullptr;
-    if (! s_workingDir)
-    {
+    static OUString s_workingDir = []() {
         OUString workingDir;
-        ::osl_getProcessWorkingDir( &workingDir.pData );
-
-        MutexGuard guard( Mutex::getGlobalMutex() );
-        if (! s_workingDir)
-        {
-            static OUString s_dir( workingDir );
-            s_workingDir = &s_dir;
-        }
-    }
-    return *s_workingDir;
+        ::osl_getProcessWorkingDir(&workingDir.pData);
+        return workingDir;
+    }();
+    return s_workingDir;
 }
 
 FilePermission::FilePermission(
diff --git a/stoc/test/testsmgr_cpnt.cxx b/stoc/test/testsmgr_cpnt.cxx
index 638ad81c1cce..ddb6e4ca1b29 100644
--- a/stoc/test/testsmgr_cpnt.cxx
+++ b/stoc/test/testsmgr_cpnt.cxx
@@ -64,13 +64,8 @@ using namespace cppu;
 
 Reference<XMultiServiceFactory> getProcessServiceManager()
 {
-    Reference<XMultiServiceFactory > s_x;
-    if (! s_x.is())
-    {
-        MutexGuard aGuard( Mutex::getGlobalMutex() );
-        if (! s_x.is())
-            s_x = createRegistryServiceFactory( OUString("stoctest.rdb"), sal_False );
-    }
+    static Reference<XMultiServiceFactory> s_x(
+        createRegistryServiceFactory(OUString("stoctest.rdb"), sal_False));
     return s_x;
 }