ILanguageSettingsChangeEvent notifications

core/org.eclipse.cdt.core.tests/model/org/eclipse/cdt/core/language/settings/providers/LanguageSettingsListenersTests.java

@@ -18,9 +18,14 @@ import junit.framework.TestCase;
 import junit.framework.TestSuite;
 
 import org.eclipse.cdt.core.model.CoreModel;
+import org.eclipse.cdt.core.settings.model.CMacroEntry;
 import org.eclipse.cdt.core.settings.model.ICConfigurationDescription;
+import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
 import org.eclipse.cdt.core.settings.model.ICProjectDescription;
 import org.eclipse.cdt.core.testplugin.ResourceHelper;
+import org.eclipse.cdt.internal.core.language.settings.providers.ILanguageSettingsChangeEvent;
+import org.eclipse.cdt.internal.core.language.settings.providers.ILanguageSettingsChangeListener;
+import org.eclipse.cdt.internal.core.language.settings.providers.LanguageSettingsProvidersSerializer;
 import org.eclipse.core.resources.IProject;
 
 /**
@@ -29,12 +34,38 @@ import org.eclipse.core.resources.IProject;
 public class LanguageSettingsListenersTests extends TestCase {
 	// Must match provider id defined as extension point 
 	private static final String EXTENSION_REGISTERER_PROVIDER_ID = "org.eclipse.cdt.core.tests.language.settings.listener.registerer.provider";
+	private static final String EXTENSION_EDITABLE_PROVIDER_ID = "org.eclipse.cdt.core.tests.custom.editable.language.settings.provider";
 	
 	private static final String PROVIDER_1 = "test.provider.1.id";
 	private static final String PROVIDER_NAME_1 = "test.provider.1.name";
 	private static final String PROVIDER_CUSTOM_GLOBAL = "test.provider.custom.global.id";
 	private static final String PROVIDER_CUSTOM_GLOBAL_NAME = "test.provider.custom.global.name";
 	
+	private static final CMacroEntry SAMPLE_LSE = new CMacroEntry("MACRO", "value",0);
+	private class MockLanguageSettingsChangeListener implements ILanguageSettingsChangeListener {
+		private int count = 0;
+		private ILanguageSettingsChangeEvent lastEvent = null;
+		
+		public void handleEvent(ILanguageSettingsChangeEvent event) {
+			count++;
+			lastEvent = event;
+		}
+
+		public int getCount() {
+			return count;
+		}
+		
+		public void resetCount() {
+			count = 0;
+			lastEvent = null;
+		}
+		
+		public ILanguageSettingsChangeEvent getLastEvent() {
+			return lastEvent;
+		}
+	}
+	private MockLanguageSettingsChangeListener mockLseListener = new MockLanguageSettingsChangeListener();
+
 	/**
 	 * Constructor.
 	 * @param name - name of the test.
@@ -50,6 +81,7 @@ public class LanguageSettingsListenersTests extends TestCase {
 
 	@Override
 	protected void tearDown() throws Exception {
+		LanguageSettingsProvidersSerializer.unregisterLanguageSettingsChangeListener(mockLseListener);
 		LanguageSettingsManager.setWorkspaceProviders(null);
 		ResourceHelper.cleanUp();
 	}
@@ -489,6 +521,543 @@ public class LanguageSettingsListenersTests extends TestCase {
 		}
 	}
 	
+	/**
+	 */
+	public void testNotification_cfgProvider_AddEmptyProvider() throws Exception {
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		// First clear default providers
+		{
+			// get project descriptions
+			ICProjectDescription writableProjDescription = CoreModel.getDefault().getProjectDescription(project);
+			assertNotNull(writableProjDescription);
+			ICConfigurationDescription[] cfgDescriptions = writableProjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+
+			// clear providers
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			cfgDescription.setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = cfgDescription.getLanguageSettingProviders();
+			assertEquals(0, storedProviders.size());
+
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, writableProjDescription);
+		}
+		
+		// register mock listener to inspect the notifications
+		LanguageSettingsProvidersSerializer.registerLanguageSettingsChangeListener(mockLseListener);
+		assertEquals(0, mockLseListener.getCount());
+		assertEquals(null, mockLseListener.getLastEvent());
+		
+		// Add empty provider
+		{
+			// get project descriptions
+			ICProjectDescription writableProjDescription = CoreModel.getDefault().getProjectDescription(project);
+			assertNotNull(writableProjDescription);
+			ICConfigurationDescription[] cfgDescriptions = writableProjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			
+			// create a provider and add to cfgDescription
+			ILanguageSettingsProvider mockProvider = new MockLanguageSettingsEditableProvider(PROVIDER_1, PROVIDER_NAME_1);
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			providers.add(mockProvider);
+			cfgDescription.setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = cfgDescription.getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+			
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, writableProjDescription);
+		}
+		
+		// No notifications expected
+		assertEquals(0, mockLseListener.getCount());
+		assertEquals(null, mockLseListener.getLastEvent());
+	}
+	
+	/**
+	 */
+	public void testNotification_cfgProvider_AddNonEmptyProvider() throws Exception {
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		// First clear default providers
+		{
+			// get project descriptions
+			ICProjectDescription writableProjDescription = CoreModel.getDefault().getProjectDescription(project);
+			assertNotNull(writableProjDescription);
+			ICConfigurationDescription[] cfgDescriptions = writableProjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			
+			// clear providers
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			cfgDescription.setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = cfgDescription.getLanguageSettingProviders();
+			assertEquals(0, storedProviders.size());
+			
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, writableProjDescription);
+		}
+		
+		// register mock listener to inspect the notifications
+		LanguageSettingsProvidersSerializer.registerLanguageSettingsChangeListener(mockLseListener);
+		assertEquals(0, mockLseListener.getCount());
+		assertEquals(null, mockLseListener.getLastEvent());
+		
+		// Add non-empty provider
+		{
+			// get project descriptions
+			ICProjectDescription writableProjDescription = CoreModel.getDefault().getProjectDescription(project);
+			assertNotNull(writableProjDescription);
+			ICConfigurationDescription[] cfgDescriptions = writableProjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			String cfgDescriptionId = cfgDescription.getId();
+			
+			// create a provider and add entries
+			MockLanguageSettingsEditableProvider mockProvider = new MockLanguageSettingsEditableProvider(PROVIDER_1, PROVIDER_NAME_1);
+			List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+			entries.add(SAMPLE_LSE);
+			mockProvider.setSettingEntries(cfgDescription, project, null, entries);
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			providers.add(mockProvider);
+			cfgDescription.setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = cfgDescription.getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+			
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, writableProjDescription);
+
+			// inspect notifications
+			assertEquals(1, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNotNull(event);
+			
+			assertEquals(project.getName(), event.getProjectName());
+			assertEquals(1, event.getConfigurationDescriptionIds().length);
+			assertEquals(cfgDescriptionId, event.getConfigurationDescriptionIds()[0]);
+			assertEquals(1, event.getResources(cfgDescriptionId).length);
+			assertEquals(project, event.getResources(cfgDescriptionId)[0]);
+		}
+	}
+	
+	/**
+	 */
+	public void testNotification_cfgProvider_SerializeEntries() throws Exception {
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		
+		// add the mock provider
+		{
+			// get project descriptions
+			ICProjectDescription writableProjDescription = CoreModel.getDefault().getProjectDescription(project);
+			assertNotNull(writableProjDescription);
+			ICConfigurationDescription[] cfgDescriptions = writableProjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			
+			// create a provider and add to cfgDescription
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			providers.add(new MockLanguageSettingsEditableProvider(PROVIDER_1, PROVIDER_NAME_1));
+			cfgDescription.setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = cfgDescription.getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+			
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, writableProjDescription);
+		}
+		
+		// register mock listener to inspect the notifications
+		LanguageSettingsProvidersSerializer.registerLanguageSettingsChangeListener(mockLseListener);
+		assertEquals(0, mockLseListener.getCount());
+		assertEquals(null, mockLseListener.getLastEvent());
+
+		// Change the provider's entries
+		{
+			// get project descriptions
+			ICProjectDescription prjDescription = CoreModel.getDefault().getProjectDescription(project, false);
+			assertNotNull(prjDescription);
+			ICConfigurationDescription[] cfgDescriptions = prjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			String cfgDescriptionId = cfgDescription.getId();
+			
+			// Add entries
+			List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+			entries.add(SAMPLE_LSE);
+			List<ILanguageSettingsProvider> providers = cfgDescription.getLanguageSettingProviders();
+			assertEquals(1, providers.size());
+			assertTrue(providers.get(0) instanceof MockLanguageSettingsEditableProvider);
+			MockLanguageSettingsEditableProvider mockProvider = (MockLanguageSettingsEditableProvider) providers.get(0);
+			mockProvider.setSettingEntries(cfgDescription, project, null, entries);
+			assertEquals(0, mockLseListener.getCount());
+			assertEquals(null, mockLseListener.getLastEvent());
+			
+			// Serialize settings
+			LanguageSettingsProvidersSerializer.serializeLanguageSettings(prjDescription);
+			// inspect event
+			assertEquals(1, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNotNull(event);
+			
+			assertEquals(project.getName(), event.getProjectName());
+			assertEquals(1, event.getConfigurationDescriptionIds().length);
+			assertEquals(cfgDescriptionId, event.getConfigurationDescriptionIds()[0]);
+			assertEquals(1, event.getResources(cfgDescriptionId).length);
+			assertEquals(project, event.getResources(cfgDescriptionId)[0]);
+			// TODO - drill to the entries
+		}
+	}
+	
+	/**
+	 */
+	public void testNotification_cfgProvider_SerializeEntriesConcurrent() throws Exception {
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		
+		// add the mock provider
+		{
+			// get project descriptions
+			ICProjectDescription writableProjDescription = CoreModel.getDefault().getProjectDescription(project);
+			assertNotNull(writableProjDescription);
+			ICConfigurationDescription[] cfgDescriptions = writableProjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			
+			// create a provider and add to cfgDescription
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			providers.add(new MockLanguageSettingsEditableProvider(PROVIDER_1, PROVIDER_NAME_1));
+			cfgDescription.setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = cfgDescription.getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+			
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, writableProjDescription);
+		}
+		
+		// register mock listener to inspect the notifications
+		LanguageSettingsProvidersSerializer.registerLanguageSettingsChangeListener(mockLseListener);
+		assertEquals(0, mockLseListener.getCount());
+		assertEquals(null, mockLseListener.getLastEvent());
+		
+		// Change the provider's entries concurrently
+		
+		// get project descriptions
+		ICProjectDescription prjDescription_1 = CoreModel.getDefault().getProjectDescription(project, false);
+		assertNotNull(prjDescription_1);
+		ICProjectDescription prjDescription_2 = CoreModel.getDefault().getProjectDescription(project, false);
+		assertNotNull(prjDescription_2);
+		{
+			ICConfigurationDescription[] cfgDescriptions = prjDescription_1.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescriptionWritable = cfgDescriptions[0];
+			String cfgDescriptionId = cfgDescriptionWritable.getId();
+			
+			// Add entries
+			List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+			entries.add(SAMPLE_LSE);
+			List<ILanguageSettingsProvider> providers = cfgDescriptionWritable.getLanguageSettingProviders();
+			assertEquals(1, providers.size());
+			assertTrue(providers.get(0) instanceof MockLanguageSettingsEditableProvider);
+			MockLanguageSettingsEditableProvider mockProvider = (MockLanguageSettingsEditableProvider) providers.get(0);
+			mockProvider.setSettingEntries(cfgDescriptionWritable, project, null, entries);
+			
+			// reset count
+			mockLseListener.resetCount();
+			assertEquals(0, mockLseListener.getCount());
+			assertNull(mockLseListener.getLastEvent());
+			
+			// Serialize settings
+			LanguageSettingsProvidersSerializer.serializeLanguageSettings(prjDescription_1);
+			// inspect event
+			assertEquals(1, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNotNull(event);
+			
+			assertEquals(project.getName(), event.getProjectName());
+			assertEquals(1, event.getConfigurationDescriptionIds().length);
+			assertEquals(cfgDescriptionId, event.getConfigurationDescriptionIds()[0]);
+			assertEquals(1, event.getResources(cfgDescriptionId).length);
+			assertEquals(project, event.getResources(cfgDescriptionId)[0]);
+			// TODO - drill to the entries
+		}
+		{
+			ICConfigurationDescription[] cfgDescriptions = prjDescription_2.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescriptionWritable = cfgDescriptions[0];
+			String cfgDescriptionId = cfgDescriptionWritable.getId();
+			
+			// Add same entries
+			List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+			entries.add(SAMPLE_LSE);
+			List<ILanguageSettingsProvider> providers = cfgDescriptionWritable.getLanguageSettingProviders();
+			assertEquals(1, providers.size());
+			assertTrue(providers.get(0) instanceof MockLanguageSettingsEditableProvider);
+			MockLanguageSettingsEditableProvider mockProvider = (MockLanguageSettingsEditableProvider) providers.get(0);
+			mockProvider.setSettingEntries(cfgDescriptionWritable, project, null, entries);
+			
+			// reset count
+			mockLseListener.resetCount();
+			assertEquals(0, mockLseListener.getCount());
+			assertNull(mockLseListener.getLastEvent());
+			
+			// Serialize settings
+			LanguageSettingsProvidersSerializer.serializeLanguageSettings(prjDescription_2);
+			// inspect event
+			assertEquals(0, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNull(event);
+		}
+	}
+	
+	/**
+	 */
+	public void testNotification_globalProvider_AddEmptyProvider() throws Exception {
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		// First clear default providers
+		{
+			// get project descriptions
+			ICProjectDescription writableProjDescription = CoreModel.getDefault().getProjectDescription(project);
+			assertNotNull(writableProjDescription);
+			ICConfigurationDescription[] cfgDescriptions = writableProjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+
+			// clear providers
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			cfgDescription.setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = cfgDescription.getLanguageSettingProviders();
+			assertEquals(0, storedProviders.size());
+
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, writableProjDescription);
+		}
+		
+		// register mock listener to inspect the notifications
+		LanguageSettingsProvidersSerializer.registerLanguageSettingsChangeListener(mockLseListener);
+		assertEquals(0, mockLseListener.getCount());
+		assertEquals(null, mockLseListener.getLastEvent());
+		
+		// Add empty global provider
+		{
+			// get project descriptions
+			ICProjectDescription writableProjDescription = CoreModel.getDefault().getProjectDescription(project);
+			assertNotNull(writableProjDescription);
+			ICConfigurationDescription[] cfgDescriptions = writableProjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			
+			// retrieve a global provider
+			ILanguageSettingsProvider wspProvider = LanguageSettingsManager.getWorkspaceProvider(EXTENSION_EDITABLE_PROVIDER_ID);
+			assertNotNull(wspProvider);
+			ILanguageSettingsProvider rawProvider = LanguageSettingsManager.getRawProvider(wspProvider);
+			assertTrue(rawProvider instanceof MockLanguageSettingsEditableProvider);
+			// clear it
+			((MockLanguageSettingsEditableProvider) rawProvider).clear();
+			assertEquals(null, wspProvider.getSettingEntries(cfgDescription, project, null));
+			// add the provider to cfgDescription
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			providers.add(wspProvider);
+			cfgDescription.setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = cfgDescription.getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+			
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, writableProjDescription);
+		}
+		
+		// No notifications expected
+		assertEquals(0, mockLseListener.getCount());
+		assertEquals(null, mockLseListener.getLastEvent());
+	}
+	
+	/**
+	 */
+	public void testNotification_globalProvider_AddNonEmptyProvider() throws Exception {
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		// First clear default providers
+		{
+			// get project descriptions
+			ICProjectDescription writableProjDescription = CoreModel.getDefault().getProjectDescription(project);
+			assertNotNull(writableProjDescription);
+			ICConfigurationDescription[] cfgDescriptions = writableProjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			
+			// clear providers
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			cfgDescription.setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = cfgDescription.getLanguageSettingProviders();
+			assertEquals(0, storedProviders.size());
+			
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, writableProjDescription);
+		}
+		
+		// register mock listener to inspect the notifications
+		LanguageSettingsProvidersSerializer.registerLanguageSettingsChangeListener(mockLseListener);
+		assertEquals(0, mockLseListener.getCount());
+		assertEquals(null, mockLseListener.getLastEvent());
+		
+		// Add non-empty provider
+		{
+			// get project descriptions
+			ICProjectDescription writableProjDescription = CoreModel.getDefault().getProjectDescription(project);
+			assertNotNull(writableProjDescription);
+			ICConfigurationDescription[] cfgDescriptions = writableProjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			String cfgDescriptionId = cfgDescription.getId();
+			
+			// retrieve a global provider
+			ILanguageSettingsProvider wspProvider = LanguageSettingsManager.getWorkspaceProvider(EXTENSION_EDITABLE_PROVIDER_ID);
+			assertNotNull(wspProvider);
+			ILanguageSettingsProvider rawProvider = LanguageSettingsManager.getRawProvider(wspProvider);
+			assertTrue(rawProvider instanceof MockLanguageSettingsEditableProvider);
+			((MockLanguageSettingsEditableProvider) rawProvider).clear();
+			// add entries
+			List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+			entries.add(SAMPLE_LSE);
+			((MockLanguageSettingsEditableProvider) rawProvider).setSettingEntries(cfgDescription, project, null, entries);
+			assertEquals(SAMPLE_LSE, wspProvider.getSettingEntries(cfgDescription, project, null).get(0));
+			// add the provider to cfgDescription
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			providers.add(wspProvider);
+			cfgDescription.setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = cfgDescription.getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, writableProjDescription);
+
+			// inspect notifications
+			assertEquals(1, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNotNull(event);
+			
+			assertEquals(project.getName(), event.getProjectName());
+			assertEquals(1, event.getConfigurationDescriptionIds().length);
+			assertEquals(cfgDescriptionId, event.getConfigurationDescriptionIds()[0]);
+			assertEquals(1, event.getResources(cfgDescriptionId).length);
+			assertEquals(project, event.getResources(cfgDescriptionId)[0]);
+		}
+	}
+	
+	/**
+	 */
+	public void testNotification_globalProvider_SerializeEntries() throws Exception {
+		IProject project = ResourceHelper.createCDTProjectWithConfig(this.getName());
+		
+		// register mock listener to inspect the notifications
+		LanguageSettingsProvidersSerializer.registerLanguageSettingsChangeListener(mockLseListener);
+		
+		// Add empty global provider
+		{
+			// get project descriptions
+			ICProjectDescription writableProjDescription = CoreModel.getDefault().getProjectDescription(project);
+			assertNotNull(writableProjDescription);
+			ICConfigurationDescription[] cfgDescriptions = writableProjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			
+			// retrieve a global provider
+			ILanguageSettingsProvider wspProvider = LanguageSettingsManager.getWorkspaceProvider(EXTENSION_EDITABLE_PROVIDER_ID);
+			assertNotNull(wspProvider);
+			ILanguageSettingsProvider rawProvider = LanguageSettingsManager.getRawProvider(wspProvider);
+			assertTrue(rawProvider instanceof MockLanguageSettingsEditableProvider);
+			// clear it
+			((MockLanguageSettingsEditableProvider) rawProvider).clear();
+			assertEquals(null, wspProvider.getSettingEntries(cfgDescription, project, null));
+			// add the provider to cfgDescription
+			List<ILanguageSettingsProvider> providers = new ArrayList<ILanguageSettingsProvider>();
+			providers.add(wspProvider);
+			cfgDescription.setLanguageSettingProviders(providers);
+			List<ILanguageSettingsProvider> storedProviders = cfgDescription.getLanguageSettingProviders();
+			assertEquals(1, storedProviders.size());
+			
+			// write to project description
+			CoreModel.getDefault().setProjectDescription(project, writableProjDescription);
+		}
+
+		// Change the provider's entries
+		{
+			// retrieve a global provider
+			ILanguageSettingsProvider wspProvider = LanguageSettingsManager.getWorkspaceProvider(EXTENSION_EDITABLE_PROVIDER_ID);
+			assertNotNull(wspProvider);
+			ILanguageSettingsProvider rawProvider = LanguageSettingsManager.getRawProvider(wspProvider);
+			assertTrue(rawProvider instanceof MockLanguageSettingsEditableProvider);
+			((MockLanguageSettingsEditableProvider) rawProvider).clear();
+			// add entries
+			List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+			entries.add(SAMPLE_LSE);
+			((MockLanguageSettingsEditableProvider) rawProvider).setSettingEntries(null, project, null, entries);
+			assertEquals(SAMPLE_LSE, wspProvider.getSettingEntries(null, project, null).get(0));
+			
+			// reset count
+			mockLseListener.resetCount();
+			assertEquals(0, mockLseListener.getCount());
+			assertEquals(null, mockLseListener.getLastEvent());
+			
+			// Serialize settings
+			LanguageSettingsProvidersSerializer.serializeLanguageSettingsWorkspace();
+
+			// get cfgDescriptionId
+			ICProjectDescription prjDescription = CoreModel.getDefault().getProjectDescription(project, false);
+			assertNotNull(prjDescription);
+			ICConfigurationDescription[] cfgDescriptions = prjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			String cfgDescriptionId = cfgDescription.getId();
+			
+			// inspect event
+			assertEquals(1, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNotNull(event);
+			
+			assertEquals(project.getName(), event.getProjectName());
+			assertEquals(1, event.getConfigurationDescriptionIds().length);
+			assertEquals(cfgDescriptionId, event.getConfigurationDescriptionIds()[0]);
+			assertEquals(1, event.getResources(cfgDescriptionId).length);
+			assertEquals(project, event.getResources(cfgDescriptionId)[0]);
+			// TODO - drill to the entries
+		}
+		// Change the provider's entries back (bug was found for this case)
+		{
+			// retrieve a global provider
+			ILanguageSettingsProvider wspProvider = LanguageSettingsManager.getWorkspaceProvider(EXTENSION_EDITABLE_PROVIDER_ID);
+			assertNotNull(wspProvider);
+			ILanguageSettingsProvider rawProvider = LanguageSettingsManager.getRawProvider(wspProvider);
+			assertTrue(rawProvider instanceof MockLanguageSettingsEditableProvider);
+			// clear the provider again
+			((MockLanguageSettingsEditableProvider) rawProvider).clear();
+			
+			// reset count
+			mockLseListener.resetCount();
+			assertEquals(0, mockLseListener.getCount());
+			assertEquals(null, mockLseListener.getLastEvent());
+			
+			// Serialize settings
+			LanguageSettingsProvidersSerializer.serializeLanguageSettingsWorkspace();
+			
+			// get cfgDescriptionId
+			ICProjectDescription prjDescription = CoreModel.getDefault().getProjectDescription(project, false);
+			assertNotNull(prjDescription);
+			ICConfigurationDescription[] cfgDescriptions = prjDescription.getConfigurations();
+			assertEquals(1, cfgDescriptions.length);
+			ICConfigurationDescription cfgDescription = cfgDescriptions[0];
+			String cfgDescriptionId = cfgDescription.getId();
+			
+			// inspect event
+			assertEquals(1, mockLseListener.getCount());
+			ILanguageSettingsChangeEvent event = mockLseListener.getLastEvent();
+			assertNotNull(event);
+			
+			assertEquals(project.getName(), event.getProjectName());
+			assertEquals(1, event.getConfigurationDescriptionIds().length);
+			assertEquals(cfgDescriptionId, event.getConfigurationDescriptionIds()[0]);
+			assertEquals(1, event.getResources(cfgDescriptionId).length);
+			assertEquals(project, event.getResources(cfgDescriptionId)[0]);
+			// TODO - drill to the entries
+		}
+	}
+
 }
 
 

core/org.eclipse.cdt.core.tests/model/org/eclipse/cdt/core/language/settings/providers/LanguageSettingsManagerTests.java

@@ -28,7 +28,7 @@ import org.eclipse.cdt.core.settings.model.ICProjectDescription;
 import org.eclipse.cdt.core.settings.model.ICSettingEntry;
 import org.eclipse.cdt.core.testplugin.CModelMock;
 import org.eclipse.cdt.core.testplugin.ResourceHelper;
-import org.eclipse.cdt.internal.core.language.settings.providers.LanguageSettingsExtensionManager;
+import org.eclipse.cdt.internal.core.language.settings.providers.LanguageSettingsProvidersSerializer;
 import org.eclipse.cdt.internal.core.settings.model.CConfigurationDescription;
 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IFolder;
@@ -561,7 +561,7 @@ public class LanguageSettingsManagerTests extends TestCase {
 
 		{
 			// retrieve local entries
-			List<ICLanguageSettingEntry> includes = LanguageSettingsExtensionManager
+			List<ICLanguageSettingEntry> includes = LanguageSettingsProvidersSerializer
 				.getLocalSettingEntriesByKind(cfgDescription, FILE_0, LANG_ID, ICSettingEntry.INCLUDE_PATH);
 			assertEquals(localIncludeEntry, includes.get(0));
 			assertEquals(1, includes.size());
@@ -569,7 +569,7 @@ public class LanguageSettingsManagerTests extends TestCase {
 
 		{
 			// retrieve system entries
-			List<ICLanguageSettingEntry> includes = LanguageSettingsExtensionManager
+			List<ICLanguageSettingEntry> includes = LanguageSettingsProvidersSerializer
 				.getSystemSettingEntriesByKind(cfgDescription, FILE_0, LANG_ID, ICSettingEntry.INCLUDE_PATH);
 			assertEquals(systemIncludeEntry, includes.get(0));
 			assertEquals(1, includes.size());
@@ -577,7 +577,7 @@ public class LanguageSettingsManagerTests extends TestCase {
 
 		{
 			// retrieve both local and system
-			List<ICLanguageSettingEntry> includes = LanguageSettingsExtensionManager
+			List<ICLanguageSettingEntry> includes = LanguageSettingsProvidersSerializer
 				.getSettingEntriesByKind(cfgDescription, FILE_0, LANG_ID, ICSettingEntry.INCLUDE_PATH);
 			assertEquals(entries.get(0), includes.get(0));
 			assertEquals(entries.get(1), includes.get(1));
@@ -799,7 +799,7 @@ public class LanguageSettingsManagerTests extends TestCase {
 		LanguageSettingsSerializable provider = new LanguageSettingsSerializable(PROVIDER_1, PROVIDER_NAME_1);
 		provider.setSettingEntries(null, file, null, entries);
 		// build the hierarchy
-		LanguageSettingsExtensionManager.buildResourceTree(provider, null, null, project);
+		LanguageSettingsProvidersSerializer.buildResourceTree(provider, null, null, project);
 		
 		// check that entries go to highest possible level
 		assertEquals(entries, LanguageSettingsManager.getSettingEntriesUpResourceTree(provider, null, file, null));

core/org.eclipse.cdt.core.tests/model/org/eclipse/cdt/core/language/settings/providers/MockLanguageSettingsEditableProvider.java

@@ -19,6 +19,10 @@ public class MockLanguageSettingsEditableProvider extends LanguageSettingsSerial
 		super();
 	}
 	
+	public MockLanguageSettingsEditableProvider(String id, String name) {
+		super(id, name);
+	}
+	
 	public MockLanguageSettingsEditableProvider cloneShallow() throws CloneNotSupportedException {
 		return (MockLanguageSettingsEditableProvider) super.cloneShallow();
 	}

core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/language/settings/providers/LanguageSettingsManager.java

@@ -54,7 +54,7 @@ public class LanguageSettingsManager {
 	 *     although individual providers return {@code null} if no settings defined.
 	 */
 	public static List<ICLanguageSettingEntry> getSettingEntriesUpResourceTree(ILanguageSettingsProvider provider, ICConfigurationDescription cfgDescription, IResource rc, String languageId) {
-		return LanguageSettingsExtensionManager.getSettingEntriesUpResourceTree(provider, cfgDescription, rc, languageId);
+		return LanguageSettingsProvidersSerializer.getSettingEntriesUpResourceTree(provider, cfgDescription, rc, languageId);
 	}
 
 	/**
@@ -71,7 +71,7 @@ public class LanguageSettingsManager {
 	 * @param project - the project which is considered the root of the resource tree.
 	 */
 	public static void buildResourceTree(LanguageSettingsSerializable provider, ICConfigurationDescription cfgDescription, String languageId, IProject project) {
-		LanguageSettingsExtensionManager.buildResourceTree(provider, cfgDescription, languageId, project);
+		LanguageSettingsProvidersSerializer.buildResourceTree(provider, cfgDescription, languageId, project);
 	}
 
 	
@@ -93,7 +93,7 @@ public class LanguageSettingsManager {
 	 */
 	// FIXME: get rid of callers PathEntryTranslator and DescriptionScannerInfoProvider 
 	public static List<ICLanguageSettingEntry> getSettingEntriesByKind(ICConfigurationDescription cfgDescription, IResource rc, String languageId, int kind) {
-		return LanguageSettingsExtensionManager.getSettingEntriesByKind(cfgDescription, rc, languageId, kind);
+		return LanguageSettingsProvidersSerializer.getSettingEntriesByKind(cfgDescription, rc, languageId, kind);
 	}
 
 	/**

core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/language/settings/providers/LanguageSettingsManager_TBD.java

@@ -20,7 +20,6 @@ import org.eclipse.cdt.internal.core.language.settings.providers.LanguageSetting
 import org.eclipse.cdt.internal.core.language.settings.providers.LanguageSettingsProvidersSerializer;
 import org.eclipse.core.resources.IProject;
 import org.eclipse.core.resources.IResource;
-import org.eclipse.core.runtime.CoreException;
 
 /**
  * This temporary class keeps the utility methods being looking for better home
@@ -53,11 +52,6 @@ public class LanguageSettingsManager_TBD {
 		return false;
 	}
 
-	@Deprecated // Shouldn't be API
-	public static void serializeWorkspaceProviders() throws CoreException {
-		LanguageSettingsProvidersSerializer.serializeLanguageSettingsWorkspace();
-	}
-
 	public static boolean isReconfigured(ILanguageSettingsProvider provider) {
 		if (provider instanceof ILanguageSettingsEditableProvider) {
 			try {

core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/language/settings/providers/LanguageSettingsSerializable.java

@@ -12,13 +12,9 @@
 package org.eclipse.cdt.core.language.settings.providers;
 
 import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Comparator;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
-import java.util.Set;
 
 import org.eclipse.cdt.core.settings.model.ICConfigurationDescription;
 import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
@@ -26,7 +22,7 @@ import org.eclipse.cdt.core.settings.model.ICSettingEntry;
 import org.eclipse.cdt.core.settings.model.util.CDataUtil;
 import org.eclipse.cdt.core.settings.model.util.LanguageSettingEntriesSerializer;
 import org.eclipse.cdt.internal.core.XmlUtil;
-import org.eclipse.cdt.internal.core.parser.util.WeakHashSet;
+import org.eclipse.cdt.internal.core.language.settings.providers.LanguageSettingsStorage;
 import org.eclipse.core.resources.IResource;
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;
@@ -45,45 +41,17 @@ public class LanguageSettingsSerializable extends LanguageSettingsBaseProvider {
 	private static final String ATTR_ID = "id"; //$NON-NLS-1$
 
 	private static final String ELEM_LANGUAGE_SCOPE = "language-scope"; //$NON-NLS-1$
-	private static final String ELEM_LANGUAGE = "language"; //$NON-NLS-1$
-	private static final String ELEM_RESOURCE = "resource"; //$NON-NLS-1$
-	private static final String ATTR_PROJECT_PATH = "project-relative-path"; //$NON-NLS-1$
-
-	private static final String ELEM_ENTRY = "entry"; //$NON-NLS-1$
-	private static final String ATTR_KIND = "kind"; //$NON-NLS-1$
 	private static final String ATTR_NAME = "name"; //$NON-NLS-1$
-	private static final String ATTR_VALUE = "value"; //$NON-NLS-1$
 	private static final String ATTR_CLASS = "class"; //$NON-NLS-1$
 	private static final String ATTR_PARAMETER = "parameter"; //$NON-NLS-1$
-	private static final String ELEM_FLAG = "flag"; //$NON-NLS-1$
-
 	private static final String ATTR_STORE_ENTRIES = "store-entries"; //$NON-NLS-1$
 	private static final String VALUE_WORKSPACE = "workspace"; //$NON-NLS-1$
 	private static final String VALUE_PROJECT = "project"; //$NON-NLS-1$
 
-	/**
-	 * Pool of LSE lists implemented as WeakHashSet. That allows to gain memory savings
-	 * at the expense of CPU time. WeakHashSet handles garbage collection when a list is not
-	 * referenced anywhere else. See JavaDoc {@link java.lang.ref.WeakReference} about weak reference objects.
-	 */
-	private static WeakHashSet<List<ICLanguageSettingEntry>> listPool = new WeakHashSet<List<ICLanguageSettingEntry>>() {
-		@Override
-		public synchronized List<ICLanguageSettingEntry> add(List<ICLanguageSettingEntry> list) {
-			return super.add(list);
-		}
-
-	};
-
 	/** Tells if language settings entries are persisted with the project or in workspace area while serializing. */
 	private boolean storeEntriesInProjectArea = false;
 
-	/**
+	private LanguageSettingsStorage fStorage = new LanguageSettingsStorage();
-	 * Storage to keep settings entries. Note that it is not necessary to keep configuration in the maps
-	 * as the configuration is always the one provider belongs to.
-	 */
-	private Map<String, // languageId
-				Map<String, // resource project path
-					List<ICLanguageSettingEntry>>> fStorage = new HashMap<String, Map<String, List<ICLanguageSettingEntry>>>();
 
 	/**
 	 * Default constructor. This constructor has to be always followed with setting id and name of the provider.
@@ -185,57 +153,6 @@ public class LanguageSettingsSerializable extends LanguageSettingsBaseProvider {
 		fStorage.clear();
 	}
 
-	/**
-	 * Internal convenience method to set language settings entries.
-	 */
-	private void setSettingEntriesInternal(String rcProjectPath, String languageId, List<ICLanguageSettingEntry> entries) {
-		if (entries!=null) {
-			Map<String, List<ICLanguageSettingEntry>> langMap = fStorage.get(languageId);
-			if (langMap==null) {
-				langMap = new HashMap<String, List<ICLanguageSettingEntry>>();
-				fStorage.put(languageId, langMap);
-			}
-			List<ICLanguageSettingEntry> sortedEntries = listPool.add(Collections.unmodifiableList(sortEntries(entries)));
-			langMap.put(rcProjectPath, sortedEntries);
-		} else {
-			// do not keep nulls in the tables
-			Map<String, List<ICLanguageSettingEntry>> langMap = fStorage.get(languageId);
-			if (langMap!=null) {
-				langMap.remove(rcProjectPath);
-				if (langMap.size()==0) {
-					fStorage.remove(languageId);
-				}
-			}
-		}
-	}
-
-	/**
-	 * Some providers may collect entries in pretty much random order. For the purposes of
-	 * predictability, UI usability and efficient storage the entries are sorted by kinds
-	 * and secondary by name for kinds where the secondary order is not significant.
-	 *
-	 * @param entries - list of entries to sort.
-	 * @return - sorted entries.
-	 */
-	protected List<ICLanguageSettingEntry> sortEntries(List<ICLanguageSettingEntry> entries) {
-		List<ICLanguageSettingEntry> sortedEntries = new ArrayList<ICLanguageSettingEntry>(entries);
-		Collections.sort(sortedEntries, new Comparator<ICLanguageSettingEntry>(){
-			/**
-			 * This comparator sorts by kinds first and the macros are sorted additionally by name.
-			 */
-			public int compare(ICLanguageSettingEntry entry0, ICLanguageSettingEntry entry1) {
-				int kind0 = entry0.getKind();
-				int kind1 = entry1.getKind();
-				if (kind0==ICSettingEntry.MACRO && kind1==ICSettingEntry.MACRO) {
-					return entry0.getName().compareTo(entry1.getName());
-				}
-
-				return kind0 - kind1;
-			}});
-
-		return sortedEntries;
-	}
-
 	/**
 	 * Sets language settings entries for the provider.
 	 * Note that the entries are not persisted at that point. To persist use TODO
@@ -248,7 +165,12 @@ public class LanguageSettingsSerializable extends LanguageSettingsBaseProvider {
 	 */
 	public void setSettingEntries(ICConfigurationDescription cfgDescription, IResource rc, String languageId, List<ICLanguageSettingEntry> entries) {
 		String rcProjectPath = rc!=null ? rc.getProjectRelativePath().toString() : null;
-		setSettingEntriesInternal(rcProjectPath, languageId, entries);
+		fStorage.setSettingEntries(rcProjectPath, languageId, entries);
+		
+//		// TODO - not sure what is more efficient, to do that or not to do that?
+//		if (fStorage.equals(lastPersistedState)) {
+//			lastPersistedState = null;
+//		}
 	}
 
 	/**
@@ -256,28 +178,27 @@ public class LanguageSettingsSerializable extends LanguageSettingsBaseProvider {
 	 * <br> Note that this list is <b>unmodifiable</b>. To modify the list copy it, change and use
 	 * {@link #setSettingEntries(ICConfigurationDescription, IResource, String, List)}.
 	 * 
+	 * <br/> Note also that <b>you can compare these lists with simple equality operator ==</b>,
+	 * as lists themselves are backed by WeakHashSet<List<ICLanguageSettingEntry>> where
+	 * identical copies (deep comparison is used) are replaced with the same one instance.
 	 */
 	@Override
 	public List<ICLanguageSettingEntry> getSettingEntries(ICConfigurationDescription cfgDescription, IResource rc, String languageId) {
-		Map<String, List<ICLanguageSettingEntry>> langMap = fStorage.get(languageId);
+		List<ICLanguageSettingEntry> entries = fStorage.getSettingEntries(cfgDescription, rc, languageId);
-		if (langMap!=null) {
+		if (entries == null) {
-			String rcProjectPath = rc!=null ? rc.getProjectRelativePath().toString() : null;
+			if (languageId!=null && (languageScope==null || languageScope.contains(languageId))) {
-			List<ICLanguageSettingEntry> entries = langMap.get(rcProjectPath);
+				entries = getSettingEntries(cfgDescription, rc, null);
-			if (entries!=null)
+			}
-				return entries;
 		}
 
-		if (languageId!=null && (languageScope==null || languageScope.contains(languageId))) {
+		return entries;
-			List<ICLanguageSettingEntry> entries = getSettingEntries(cfgDescription, rc, null);
-			return entries;
-		}
-
-		return null;
 	}
 
 	/**
 	 * Serialize the provider under parent XML element.
 	 * This is convenience method not intended to be overridden on purpose.
+	 * Override {@link #serializeAttributes(Element)} or
+	 * {@link #serializeEntries(Element)} instead.
 	 * 
 	 * @param parentElement - element where to serialize.
 	 * @return - newly created <provider> element. That element will already be
@@ -329,98 +250,18 @@ public class LanguageSettingsSerializable extends LanguageSettingsBaseProvider {
 	 * @param elementProvider - element where to serialize the entries.
 	 */
 	public void serializeEntries(Element elementProvider) {
-		for (Entry<String, Map<String, List<ICLanguageSettingEntry>>> entryLang : fStorage.entrySet()) {
+		fStorage.serializeEntries(elementProvider);
-			serializeLanguage(elementProvider, entryLang);
-		}
 	}
 
-	/**
-	 * Serialize the provider entries for a given language list.
-	 */
-	private void serializeLanguage(Element parentElement, Entry<String, Map<String, List<ICLanguageSettingEntry>>> entryLang) {
-		String langId = entryLang.getKey();
-		if (langId!=null) {
-			Element elementLanguage = XmlUtil.appendElement(parentElement, ELEM_LANGUAGE, new String[] {ATTR_ID, langId});
-			parentElement = elementLanguage;
-		}
-		for (Entry<String, List<ICLanguageSettingEntry>> entryRc : entryLang.getValue().entrySet()) {
-			serializeResource(parentElement, entryRc);
-		}
-	}
-
-	/**
-	 * Serialize the provider entries for a given resource list.
-	 */
-	private void serializeResource(Element parentElement, Entry<String, List<ICLanguageSettingEntry>> entryRc) {
-		String rcProjectPath = entryRc.getKey();
-		if (rcProjectPath!=null) {
-			Element elementRc = XmlUtil.appendElement(parentElement, ELEM_RESOURCE, new String[] {ATTR_PROJECT_PATH, rcProjectPath});
-			parentElement = elementRc;
-		}
-		serializeSettingEntries(parentElement, entryRc.getValue());
-	}
-
-	/**
-	 * Serialize given settings entries.
-	 */
-	private void serializeSettingEntries(Element parentElement, List<ICLanguageSettingEntry> settingEntries) {
-		for (ICLanguageSettingEntry entry : settingEntries) {
-			Element elementSettingEntry = XmlUtil.appendElement(parentElement, ELEM_ENTRY, new String[] {
-					ATTR_KIND, LanguageSettingEntriesSerializer.kindToString(entry.getKind()),
-					ATTR_NAME, entry.getName(),
-				});
-			switch(entry.getKind()) {
-			case ICSettingEntry.MACRO:
-				elementSettingEntry.setAttribute(ATTR_VALUE, entry.getValue());
-				break;
-//			case ICLanguageSettingEntry.LIBRARY_FILE:
-//				// TODO: sourceAttachment fields may need to be covered
-//				break;
-			}
-			int flags = entry.getFlags();
-			if (flags!=0) {
-				// Element elementFlag =
-				XmlUtil.appendElement(elementSettingEntry, ELEM_FLAG, new String[] {
-						ATTR_VALUE, LanguageSettingEntriesSerializer.composeFlagsString(entry.getFlags())
-					});
-			}
-		}
-	}
-
-	/**
-	 * Load a setting entry from XML element.
-	 */
-	private ICLanguageSettingEntry loadSettingEntry(Node parentElement) {
-		String settingKind = XmlUtil.determineAttributeValue(parentElement, ATTR_KIND);
-		String settingName = XmlUtil.determineAttributeValue(parentElement, ATTR_NAME);
-
-		NodeList flagNodes = parentElement.getChildNodes();
-		int flags = 0;
-		for (int i=0;i<flagNodes.getLength();i++) {
-			Node flagNode = flagNodes.item(i);
-			if(flagNode.getNodeType() != Node.ELEMENT_NODE || !ELEM_FLAG.equals(flagNode.getNodeName()))
-				continue;
-
-			String settingFlags = XmlUtil.determineAttributeValue(flagNode, ATTR_VALUE);
-			int bitFlag = LanguageSettingEntriesSerializer.composeFlags(settingFlags);
-			flags |= bitFlag;
-
-		}
-
-		String settingValue = null;
-		int kind = LanguageSettingEntriesSerializer.stringToKind(settingKind);
-		if (kind == ICSettingEntry.MACRO)
-			settingValue = XmlUtil.determineAttributeValue(parentElement, ATTR_VALUE);
-		ICLanguageSettingEntry entry = (ICLanguageSettingEntry) CDataUtil.createEntry(kind, settingName, settingValue, null, flags);
-		return entry;
-	}
-
-
 	/**
 	 * Load provider from XML provider element.
+	 * This is convenience method not intended to be overridden on purpose.
+	 * Override {@link #loadAttributes(Element)} or
+	 * {@link #loadEntries(Element)} instead.
+	 * 
 	 * @param providerNode - XML element <provider> to load provider from.
 	 */
-	public void load(Element providerNode) {
+	final public void load(Element providerNode) {
 		fStorage.clear();
 		languageScope = null;
 
@@ -431,6 +272,18 @@ public class LanguageSettingsSerializable extends LanguageSettingsBaseProvider {
 		}
 	}
 
+	/**
+	 * Determine and set language scope from given XML node.
+	 */
+	private void loadLanguageScopeElement(Node parentNode) {
+		if (languageScope==null) {
+			languageScope = new ArrayList<String>();
+		}
+		String id = XmlUtil.determineAttributeValue(parentNode, ATTR_ID);
+		languageScope.add(id);
+	
+	}
+
 	/**
 	 * Load attributes from XML provider element.
 	 * @param providerNode - XML element <provider> to load attributes from.
@@ -464,123 +317,7 @@ public class LanguageSettingsSerializable extends LanguageSettingsBaseProvider {
 	 * @param providerNode - parent XML element <provider> where entries are defined.
 	 */
 	public void loadEntries(Element providerNode) {
-		List<ICLanguageSettingEntry> settings = new ArrayList<ICLanguageSettingEntry>();
+		fStorage.loadEntries(providerNode);
-		NodeList nodes = providerNode.getChildNodes();
-		for (int i=0;i<nodes.getLength();i++) {
-			Node elementNode = nodes.item(i);
-			if(elementNode.getNodeType() != Node.ELEMENT_NODE)
-				continue;
-
-			if (ELEM_LANGUAGE.equals(elementNode.getNodeName())) {
-				loadLanguageElement(elementNode, null);
-			} else if (ELEM_RESOURCE.equals(elementNode.getNodeName())) {
-				loadResourceElement(elementNode, null, null);
-			} else if (ELEM_ENTRY.equals(elementNode.getNodeName())) {
-				ICLanguageSettingEntry entry = loadSettingEntry(elementNode);
-				if (entry!=null) {
-					settings.add(entry);
-				}
-			}
-		}
-		// set settings
-		if (settings.size()>0) {
-			setSettingEntriesInternal(null, null, settings);
-		}
-	}
-
-	/**
-	 * Determine and set language scope from given XML node.
-	 */
-	private void loadLanguageScopeElement(Node parentNode) {
-		if (languageScope==null) {
-			languageScope = new ArrayList<String>();
-		}
-		String id = XmlUtil.determineAttributeValue(parentNode, ATTR_ID);
-		languageScope.add(id);
-
-	}
-
-	/**
-	 * Load entries defined in language element.
-	 */
-	private void loadLanguageElement(Node parentNode, String cfgId) {
-		String langId = XmlUtil.determineAttributeValue(parentNode, ATTR_ID);
-		if (langId.length()==0) {
-			langId=null;
-		}
-
-		List<ICLanguageSettingEntry> settings = new ArrayList<ICLanguageSettingEntry>();
-		NodeList nodes = parentNode.getChildNodes();
-		for (int i=0;i<nodes.getLength();i++) {
-			Node elementNode = nodes.item(i);
-			if(elementNode.getNodeType() != Node.ELEMENT_NODE)
-				continue;
-
-			if (ELEM_RESOURCE.equals(elementNode.getNodeName())) {
-				loadResourceElement(elementNode, cfgId, langId);
-			} else if (ELEM_ENTRY.equals(elementNode.getNodeName())) {
-				ICLanguageSettingEntry entry = loadSettingEntry(elementNode);
-				if (entry!=null) {
-					settings.add(entry);
-				}
-			}
-		}
-		// set settings
-		if (settings.size()>0) {
-			setSettingEntriesInternal(null, langId, settings);
-		}
-	}
-
-	/**
-	 * Load entries defined in resource element.
-	 */
-	private void loadResourceElement(Node parentNode, String cfgId, String langId) {
-		String rcProjectPath = XmlUtil.determineAttributeValue(parentNode, ATTR_PROJECT_PATH);
-
-		List<ICLanguageSettingEntry> settings = new ArrayList<ICLanguageSettingEntry>();
-		NodeList nodes = parentNode.getChildNodes();
-		for (int i=0;i<nodes.getLength();i++) {
-			Node elementNode = nodes.item(i);
-			if(elementNode.getNodeType() != Node.ELEMENT_NODE)
-				continue;
-
-			if (ELEM_ENTRY.equals(elementNode.getNodeName())) {
-				ICLanguageSettingEntry entry = loadSettingEntry(elementNode);
-				if (entry!=null) {
-					settings.add(entry);
-				}
-			}
-		}
-
-		// set settings
-		if (settings.size()>0) {
-			setSettingEntriesInternal(rcProjectPath, langId, settings);
-		}
-	}
-
-	/**
-	 * Clone storage for the entries. Copies references for lists of entries as a whole.
-	 * Note that is OK as the lists kept in storage are unmodifiable.
-	 */
-	private Map<String, Map<String, List<ICLanguageSettingEntry>>> cloneStorage() {
-		Map<String, // languageId
-			Map<String, // resource
-				List<ICLanguageSettingEntry>>> storageClone = new HashMap<String, Map<String, List<ICLanguageSettingEntry>>>();
-		Set<Entry<String, Map<String, List<ICLanguageSettingEntry>>>> entrySetLang = fStorage.entrySet();
-		for (Entry<String, Map<String, List<ICLanguageSettingEntry>>> entryLang : entrySetLang) {
-			String langId = entryLang.getKey();
-			Map<String, List<ICLanguageSettingEntry>> mapRc = entryLang.getValue();
-			Map<String, List<ICLanguageSettingEntry>> mapRcClone = new HashMap<String, List<ICLanguageSettingEntry>>();
-			Set<Entry<String, List<ICLanguageSettingEntry>>> entrySetRc = mapRc.entrySet();
-			for (Entry<String, List<ICLanguageSettingEntry>> entryRc : entrySetRc) {
-				String rcProjectPath = entryRc.getKey();
-				List<ICLanguageSettingEntry> lsEntries = entryRc.getValue();
-				// don't need to clone entries, they are from the LSE pool
-				mapRcClone.put(rcProjectPath, lsEntries);
-			}
-			storageClone.put(langId, mapRcClone);
-		}
-		return storageClone;
 	}
 	
 	/**
@@ -592,7 +329,7 @@ public class LanguageSettingsSerializable extends LanguageSettingsBaseProvider {
 		if (languageScope!=null)
 			clone.languageScope = new ArrayList<String>(languageScope);
 
-		clone.fStorage = new HashMap<String, Map<String, List<ICLanguageSettingEntry>>>();
+		clone.fStorage = new LanguageSettingsStorage();
 		return clone;
 	}
 
@@ -610,7 +347,7 @@ public class LanguageSettingsSerializable extends LanguageSettingsBaseProvider {
 	@Override
 	protected LanguageSettingsSerializable clone() throws CloneNotSupportedException {
 		LanguageSettingsSerializable clone = cloneShallowInternal();
-		clone.fStorage = cloneStorage();
+		clone.fStorage = fStorage.cloneStorage();
 		return clone;
 	}
 
@@ -680,4 +417,11 @@ public class LanguageSettingsSerializable extends LanguageSettingsBaseProvider {
 			return false;
 		return true;
 	}
+	
+	/**
+	 * @noreference This method is not intended to be referenced by clients.
+	 */
+	public LanguageSettingsStorage getStorageInternal() {
+		return fStorage;
+	}
 }

core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/language/settings/providers/LanguageSettingsSerializableEditable.java

@@ -13,7 +13,8 @@ package org.eclipse.cdt.core.language.settings.providers;
 
 // TODO: move ILanguageSettingsEditableProvider here 
 
-public class LanguageSettingsSerializableEditable extends LanguageSettingsSerializable implements ILanguageSettingsEditableProvider {
+// TODO this one is unused - remove
+final public class LanguageSettingsSerializableEditable extends LanguageSettingsSerializable implements ILanguageSettingsEditableProvider {
 	@Override
 	public LanguageSettingsSerializableEditable clone() throws CloneNotSupportedException {
 		return (LanguageSettingsSerializableEditable) super.clone();

core/org.eclipse.cdt.core/model/org/eclipse/cdt/core/settings/model/ICConfigurationDescription.java

@@ -395,6 +395,8 @@ public interface ICConfigurationDescription extends ICSettingContainer, ICSettin
 	 * or preprocessor macros.
 	 * 
 	 * @param providers the list of providers to assign to the configuration description.
+	 *    Warning: the providers will be cloned before actual addition to the project model
+	 *    due to TODO - very important reason but I forgot why by now.
 	 * 
 	 * @since 6.0
 	 */

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/language/settings/providers/ILanguageSettingsChangeEvent.java

@@ -0,0 +1,36 @@
+/*******************************************************************************
+ * Copyright (c) 2011, 2011 Andrew Gvozdev and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Andrew Gvozdev - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.cdt.internal.core.language.settings.providers;
+
+import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
+import org.eclipse.core.resources.IResource;
+
+/**
+ * Contains the details of changes that occurred as a result of modifying
+ * language settings entries {@link ICLanguageSettingEntry}. 
+ * 
+ * @noextend This interface is not intended to be extended by clients.
+ * @noimplement This interface is not intended to be implemented by clients.
+ */
+public interface ILanguageSettingsChangeEvent {
+	public String getProjectName();
+	
+	public String[] getConfigurationDescriptionIds();
+	
+	public IResource[] getResources(String cfgDescriptionId);
+	
+//	// AG - YAGNI
+//	public List<ICLanguageSettingEntry> getSettingEntriesOld(ICConfigurationDescription cfgDescription, IResource rc, String languageId);
+//	public List<ICLanguageSettingEntry> getSettingEntriesNew(ICConfigurationDescription cfgDescription, IResource rc, String languageId);
+//	// AG - or maybe
+//	ILanguageSettingsDelta getDelta(ICConfigurationDescription cfgDescription);
+
+}

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/language/settings/providers/ILanguageSettingsChangeListener.java

@@ -0,0 +1,22 @@
+/*******************************************************************************
+ * Copyright (c) 2011, 2011 Andrew Gvozdev and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Andrew Gvozdev - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.cdt.internal.core.language.settings.providers;
+
+/**
+ * Listens to changes in language settings.
+ */
+public interface ILanguageSettingsChangeListener {
+	/**
+	 * Indicates that language settings have been changed.
+	 * @param event
+	 */
+	public void handleEvent(ILanguageSettingsChangeEvent event);
+}

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/language/settings/providers/LanguageSettingsDelta.java

@@ -0,0 +1,155 @@
+/*******************************************************************************
+ * Copyright (c) 2011, 2011 Andrew Gvozdev and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Andrew Gvozdev - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.cdt.internal.core.language.settings.providers;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+
+import org.eclipse.cdt.core.settings.model.ICConfigurationDescription;
+import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
+import org.eclipse.cdt.core.settings.model.ICSettingEntry;
+import org.eclipse.core.resources.IProject;
+import org.eclipse.core.resources.IResource;
+import org.eclipse.core.resources.IWorkspaceRoot;
+import org.eclipse.core.runtime.Assert;
+
+
+// TODO possibly make an interface from that
+public class LanguageSettingsDelta {
+	// maps need to be ordered by providers
+	private LinkedHashMap<String, // providerId
+					LanguageSettingsStorage> oldLanguageSettingsState;
+	private LinkedHashMap<String, // providerId
+					LanguageSettingsStorage> newLanguageSettingsState;
+	
+	public LanguageSettingsDelta(LinkedHashMap<String, LanguageSettingsStorage> oldState, LinkedHashMap<String, LanguageSettingsStorage> newState) {
+		oldLanguageSettingsState = oldState;
+		newLanguageSettingsState = newState;
+	}
+
+	// FIXME - this API is no good
+	public Set<IResource> getChangedResources(IProject project, ICConfigurationDescription cfgDescription) {
+		Set<IResource> resources = new HashSet<IResource>();
+		
+		// Ordered collections
+		Collection<LanguageSettingsStorage> oldStateStorages = oldLanguageSettingsState.values();
+		Collection<LanguageSettingsStorage> newStateStorages = newLanguageSettingsState.values();
+
+		for (LanguageSettingsStorage lss : oldStateStorages) {
+//			Map<String, // languageId
+//				Map<String, // resource project path
+//					List<ICLanguageSettingEntry>>>
+			Map<String, Map<String, List<ICLanguageSettingEntry>>> mapInternal = lss.getMapInternal();
+			synchronized (mapInternal) {
+				for (Entry<String, Map<String, List<ICLanguageSettingEntry>>> entryLang : mapInternal.entrySet()) {
+					String langId = entryLang.getKey();
+					for (Entry<String, List<ICLanguageSettingEntry>> entryRc : entryLang.getValue().entrySet()) {
+						String rcName = entryRc.getKey();
+						IResource rc = (rcName != null) ? project.findMember(rcName) : project;
+						if (resources.contains(rc))
+							continue;
+						
+						List<ICLanguageSettingEntry> lsEntriesOld = entryRc.getValue();
+						List<ICLanguageSettingEntry> lsEntriesNew = getSettingEntries(newStateStorages, cfgDescription, rc, langId);
+						
+						if (!lsEntriesNew.equals(lsEntriesOld) && !(lsEntriesOld==null && lsEntriesNew.size()==0)) {
+							resources.add(rc);
+						}
+					}
+				}
+			}
+		}
+		for (LanguageSettingsStorage lss : newStateStorages) {
+//			Map<String, // languageId
+//				Map<String, // resource project path
+//					List<ICLanguageSettingEntry>>>
+			Map<String, Map<String, List<ICLanguageSettingEntry>>> mapInternal = lss.getMapInternal();
+			synchronized (mapInternal) {
+				for (Entry<String, Map<String, List<ICLanguageSettingEntry>>> entryLang : mapInternal.entrySet()) {
+					String langId = entryLang.getKey();
+					for (Entry<String, List<ICLanguageSettingEntry>> entryRc : entryLang.getValue().entrySet()) {
+						String rcName = entryRc.getKey();
+						IResource rc = (rcName != null) ? project.findMember(rcName) : project;
+						if (resources.contains(rc))
+							continue;
+						
+						List<ICLanguageSettingEntry> lsEntriesNew = entryRc.getValue();
+						List<ICLanguageSettingEntry> lsEntriesOld = getSettingEntries(oldStateStorages, cfgDescription, rc, langId);
+						
+						if (!lsEntriesOld.equals(lsEntriesNew) && !(lsEntriesNew==null && lsEntriesOld.size()==0)) {
+							resources.add(rc);
+						}
+					}
+				}
+			}
+		}
+		
+		return resources;
+	}
+
+	private static boolean checkBit(int flags, int bit) {
+		return (flags & bit) == bit;
+	}
+
+	private static List<ICLanguageSettingEntry> getSettingEntries(Collection<LanguageSettingsStorage> stores, ICConfigurationDescription cfgDescription, IResource rc, String languageId) {
+		List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+		List<String> alreadyAdded = new ArrayList<String>();
+	
+		for (LanguageSettingsStorage store: stores) {
+			List<ICLanguageSettingEntry> providerEntries = getSettingEntriesUpResourceTree(store, cfgDescription, rc, languageId);
+			for (ICLanguageSettingEntry entry : providerEntries) {
+				if (entry!=null) {
+					String entryName = entry.getName();
+					// Only first entry is considered
+					// Entry flagged as "UNDEFINED" prevents adding entry with the same name down the line
+					if (!alreadyAdded.contains(entryName)) {
+						int flags = entry.getFlags();
+						if (!checkBit(flags, ICSettingEntry.UNDEFINED)) {
+							entries.add(entry);
+						}
+						alreadyAdded.add(entryName);
+					}
+				}
+			}
+		}
+	
+		return entries;
+	}
+
+	private static List<ICLanguageSettingEntry> getSettingEntriesUpResourceTree(LanguageSettingsStorage store, ICConfigurationDescription cfgDescription, IResource rc, String languageId) {
+		Assert.isTrue( !(rc instanceof IWorkspaceRoot) );
+		if (store!=null) {
+			List<ICLanguageSettingEntry> entries = store.getSettingEntries(cfgDescription, rc, languageId);
+			if (entries!=null) {
+				return new ArrayList<ICLanguageSettingEntry>(entries);
+			}
+			if (rc!=null) {
+				IResource parentFolder = (rc instanceof IProject) ? null : rc.getParent();
+				if (parentFolder!=null) {
+					return getSettingEntriesUpResourceTree(store, cfgDescription, parentFolder, languageId);
+				}
+				// if out of parent resources - get default entries for the applicable language scope
+				entries = store.getSettingEntries(null, null, languageId);
+				if (entries!=null) {
+					return new ArrayList<ICLanguageSettingEntry>(entries);
+				}
+			}
+		}
+	
+		return new ArrayList<ICLanguageSettingEntry>(0);
+	}
+}

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/language/settings/providers/LanguageSettingsExtensionManager.java

@@ -13,10 +13,8 @@ package org.eclipse.cdt.internal.core.language.settings.providers;
 
 import java.util.ArrayList;
 import java.util.Comparator;
-import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
-import java.util.Map;
 import java.util.Set;
 import java.util.TreeSet;
 
@@ -26,19 +24,9 @@ import org.eclipse.cdt.core.language.settings.providers.ILanguageSettingsEditabl
 import org.eclipse.cdt.core.language.settings.providers.ILanguageSettingsProvider;
 import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsBaseProvider;
 import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsSerializable;
-import org.eclipse.cdt.core.model.ILanguage;
-import org.eclipse.cdt.core.model.LanguageManager;
-import org.eclipse.cdt.core.settings.model.ICConfigurationDescription;
 import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
-import org.eclipse.cdt.core.settings.model.ICSettingEntry;
 import org.eclipse.cdt.core.settings.model.util.CDataUtil;
 import org.eclipse.cdt.core.settings.model.util.LanguageSettingEntriesSerializer;
-import org.eclipse.core.resources.IContainer;
-import org.eclipse.core.resources.IFile;
-import org.eclipse.core.resources.IProject;
-import org.eclipse.core.resources.IResource;
-import org.eclipse.core.resources.IWorkspaceRoot;
-import org.eclipse.core.runtime.Assert;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IConfigurationElement;
 import org.eclipse.core.runtime.IExtension;
@@ -340,267 +328,6 @@ public class LanguageSettingsExtensionManager {
 		return list;
 	}
 
-	private static List<ICLanguageSettingEntry> safeGetSettingEntries(ILanguageSettingsProvider provider,
-			ICConfigurationDescription cfgDescription, IResource rc, String languageId) {
-		
-		try {
-			return provider.getSettingEntries(cfgDescription, rc, languageId);
-		} catch (Throwable e) {
-			String cfgId = cfgDescription!=null ? cfgDescription.getId() : null;
-			String msg = "Exception in provider "+provider.getId()+": getSettingEntries("+cfgId+", "+rc+", "+languageId+")";
-			CCorePlugin.log(msg, e);
-			// return empty array to prevent climbing up the resource tree 
-			return new ArrayList<ICLanguageSettingEntry>(0);
-		}
-	}
-
-	/**
-	 * Returns the list of setting entries of the given provider
-	 * for the given configuration description, resource and language.
-	 * This method reaches to the parent folder of the resource recursively
-	 * in case the resource does not define the entries for the given provider.
-	 * 
-	 * @param provider - language settings provider.
-	 * @param cfgDescription - configuration description.
-	 * @param rc - resource such as file or folder.
-	 * @param languageId - language id.
-	 * 
-	 * @return the list of setting entries. Never returns {@code null}
-	 *     although individual providers mandated to return {@code null} if no settings defined.
-	 */
-	public static List<ICLanguageSettingEntry> getSettingEntriesUpResourceTree(ILanguageSettingsProvider provider, ICConfigurationDescription cfgDescription, IResource rc, String languageId) {
-		Assert.isTrue( !(rc instanceof IWorkspaceRoot) );
-		if (provider!=null) {
-			List<ICLanguageSettingEntry> entries = safeGetSettingEntries(provider, cfgDescription, rc, languageId);
-			if (entries!=null) {
-				return new ArrayList<ICLanguageSettingEntry>(entries);
-			}
-			if (rc!=null) {
-				IResource parentFolder = (rc instanceof IProject) ? null : rc.getParent();
-				if (parentFolder!=null) {
-					return getSettingEntriesUpResourceTree(provider, cfgDescription, parentFolder, languageId);
-				}
-				// if out of parent resources - get default entries for the applicable language scope
-				entries = safeGetSettingEntries(provider, null, null, languageId);
-				if (entries!=null) {
-					return new ArrayList<ICLanguageSettingEntry>(entries);
-				}
-			}
-		}
-	
-		return new ArrayList<ICLanguageSettingEntry>(0);
-	}
-
-	/**
-	 * Builds for the provider a nice looking resource tree to present hierarchical view to the user.
-	 * Note that it is not advisable to "compact" the tree because of potential loss of information
-	 * which is especially important during partial or incremental builds.
-	 * 
-	 * @param provider - language settings provider to build the tree for.
-	 * @param cfgDescription - configuration description.
-	 * @param languageId - language ID.
-	 * @param folder - container where the tree roots.
-	 */
-	public static void buildResourceTree(LanguageSettingsSerializable provider, ICConfigurationDescription cfgDescription, String languageId, IContainer folder) {
-		IResource[] members = null;
-		try {
-			members = folder.members();
-		} catch (Exception e) {
-			CCorePlugin.log(e);
-		}
-		if (members==null)
-			return;
-		
-		for (IResource rc : members) {
-			if (rc instanceof IContainer) {
-				buildResourceTree(provider, cfgDescription, languageId, (IContainer) rc);
-			}
-		}
-
-		int rcNumber = members.length;
-		
-		Map<List<ICLanguageSettingEntry>, Integer> listMap = new HashMap<List<ICLanguageSettingEntry>, Integer>();
-		
-		// on the first pass find majority entries
-		List<ICLanguageSettingEntry> majorityEntries = null;
-		List<ICLanguageSettingEntry> candidate = null;
-		int candidateCount = 0;
-		for (IResource rc : members) {
-			if (!isLanguageInScope(rc, cfgDescription, languageId)) {
-				rcNumber--;
-			} else {
-				List<ICLanguageSettingEntry> entries = provider.getSettingEntries(null, rc, languageId);
-				if (entries==null && rc instanceof IContainer) {
-					rcNumber--;
-				} else {
-					Integer count = listMap.get(entries);
-					if (count==null) {
-						count = 0;
-					}
-					count++;
-					
-					if (count>candidateCount) {
-						candidateCount = count;
-						candidate = entries;
-					}
-					
-					listMap.put(entries, count);
-				}
-			}
-
-			if (candidateCount > rcNumber/2) {
-				majorityEntries = candidate;
-				break;
-			}
-		}
-		
-		if (majorityEntries!=null) {
-			provider.setSettingEntries(cfgDescription, folder, languageId, majorityEntries);
-		}
-		
-		// second pass - assign the entries to the folders
-		for (IResource rc : members) {
-			List<ICLanguageSettingEntry> entries = provider.getSettingEntries(null, rc, languageId);
-			if (entries!=null && entries==majorityEntries) {
-				if (!(rc instanceof IFile)) { // preserve information which files were collected
-					provider.setSettingEntries(cfgDescription, rc, languageId, null);
-				}
-			}
-		}
-	}
-
-	private static boolean isLanguageInScope(IResource rc, ICConfigurationDescription cfgDescription, String languageId) {
-		if (rc instanceof IFile) {
-			ILanguage lang = null;
-			try {
-				lang = LanguageManager.getInstance().getLanguageForFile((IFile) rc, cfgDescription);
-			} catch (CoreException e) {
-				CCorePlugin.log("Error loading language settings providers extensions", e); //$NON-NLS-1$
-			}
-			if (lang==null || (languageId!=null && !languageId.equals(lang.getId()))) {
-				return false;
-			}
-		}
-		return true;
-	}
-	
-	private static boolean checkBit(int flags, int bit) {
-		return (flags & bit) == bit;
-	}
-
-	/**
-	 * Returns the list of setting entries of a certain kind (such as include paths)
-	 * for the given configuration description, resource and language. This is a
-	 * combined list for all providers taking into account settings of parent folder
-	 * if settings for the given resource are not defined.
-	 * 
-	 * @param cfgDescription - configuration description.
-	 * @param rc - resource such as file or folder.
-	 * @param languageId - language id.
-	 * @param kind - kind of language settings entries, such as
-	 *     {@link ICSettingEntry#INCLUDE_PATH} etc. This is a binary flag
-	 *     and it is possible to specify composite kind.
-	 *     Use {@link ICSettingEntry#ALL} to get all kinds.
-	 * @param checkLocality - specifies if parameter {@code isLocal} should be considered.
-	 * @param isLocal - {@code true} if "local" entries should be provided and
-	 *     {@code false} for "system" entries. This makes sense for include paths where
-	 *     [#include "..."] is "local" and [#include <...>] is system.
-	 * 
-	 * @return the list of setting entries found.
-	 */
-	private static List<ICLanguageSettingEntry> getSettingEntriesByKind(ICConfigurationDescription cfgDescription,
-			IResource rc, String languageId, int kind, boolean checkLocality, boolean isLocal) {
-
-		List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
-		List<String> alreadyAdded = new ArrayList<String>();
-	
-		List<ILanguageSettingsProvider> providers = cfgDescription.getLanguageSettingProviders();
-		for (ILanguageSettingsProvider provider: providers) {
-			List<ICLanguageSettingEntry> providerEntries = getSettingEntriesUpResourceTree(provider, cfgDescription, rc, languageId);
-			for (ICLanguageSettingEntry entry : providerEntries) {
-				if (entry!=null) {
-					String entryName = entry.getName();
-					boolean isRightKind = (entry.getKind() & kind) != 0;
-					// Only first entry is considered
-					// Entry flagged as "UNDEFINED" prevents adding entry with the same name down the line
-					if (isRightKind && !alreadyAdded.contains(entryName)) {
-						int flags = entry.getFlags();
-						boolean isRightLocal = !checkLocality || (checkBit(flags, ICSettingEntry.LOCAL) == isLocal);
-						if (isRightLocal) {
-							if (!checkBit(flags, ICSettingEntry.UNDEFINED)) {
-								entries.add(entry);
-							}
-							alreadyAdded.add(entryName);
-						}
-					}
-				}
-			}
-		}
-	
-		return entries;
-	}
-
-	/**
-	 * Returns the list of setting entries of a certain kind (such as include paths)
-	 * for the given configuration description, resource and language. This is a
-	 * combined list for all providers taking into account settings of parent folder
-	 * if settings for the given resource are not defined. For include paths both
-	 * local (#include "...") and system (#include <...>) entries are returned.
-	 * 
-	 * @param cfgDescription - configuration description.
-	 * @param rc - resource such as file or folder.
-	 * @param languageId - language id.
-	 * @param kind - kind of language settings entries, such as
-	 *     {@link ICSettingEntry#INCLUDE_PATH} etc. This is a binary flag
-	 *     and it is possible to specify composite kind.
-	 *     Use {@link ICSettingEntry#ALL} to get all kinds.
-	 * 
-	 * @return the list of setting entries.
-	 */
-	public static List<ICLanguageSettingEntry> getSettingEntriesByKind(ICConfigurationDescription cfgDescription, IResource rc, String languageId, int kind) {
-		return getSettingEntriesByKind(cfgDescription, rc, languageId, kind, /* checkLocality */ false, /* isLocal */ false);
-	}
-
-	/**
-	 * Returns the list of "system" (such as [#include <...>]) setting entries of a certain kind 
-	 * for the given configuration description, resource and language. This is a
-	 * combined list for all providers taking into account settings of parent folder
-	 * if settings for the given resource are not defined.
-	 * 
-	 * @param cfgDescription - configuration description.
-	 * @param rc - resource such as file or folder.
-	 * @param languageId - language id.
-	 * @param kind - kind of language settings entries, such as
-	 *     {@link ICSettingEntry#INCLUDE_PATH} etc. This is a binary flag
-	 *     and it is possible to specify composite kind.
-	 *     Use {@link ICSettingEntry#ALL} to get all kinds.
-	 * 
-	 * @return the list of setting entries.
-	 */
-	public static List<ICLanguageSettingEntry> getSystemSettingEntriesByKind(ICConfigurationDescription cfgDescription, IResource rc, String languageId, int kind) {
-		return getSettingEntriesByKind(cfgDescription, rc, languageId, kind, /* checkLocality */ true, /* isLocal */ false);
-	}
-
-	/**
-	 * Returns the list of "local" (such as [#include "..."]) setting entries of a certain kind 
-	 * for the given configuration description, resource and language. This is a
-	 * combined list for all providers taking into account settings of parent folder
-	 * if settings for the given resource are not defined.
-	 * 
-	 * @param cfgDescription - configuration description.
-	 * @param rc - resource such as file or folder.
-	 * @param languageId - language id.
-	 * @param kind - kind of language settings entries, such as
-	 *     {@link ICSettingEntry#INCLUDE_PATH} etc. This is a binary flag
-	 *     and it is possible to specify composite kind.
-	 *     Use {@link ICSettingEntry#ALL} to get all kinds.
-	 * 
-	 * @return the list of setting entries.
-	 */
-	public static List<ICLanguageSettingEntry> getLocalSettingEntriesByKind(ICConfigurationDescription cfgDescription, IResource rc, String languageId, int kind) {
-		return getSettingEntriesByKind(cfgDescription, rc, languageId, kind, /* checkLocality */ true, /* isLocal */ true);
-	}
-
 	public static boolean equalsExtensionProviderShallow(ILanguageSettingsEditableProvider provider) throws CloneNotSupportedException {
 		String id = provider.getId();
 		ILanguageSettingsProvider extensionProviderShallow = getExtensionProviderShallow(id);

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/language/settings/providers/LanguageSettingsProvidersSerializer.java

@@ -25,19 +25,29 @@ import org.eclipse.cdt.core.language.settings.providers.ILanguageSettingsProvide
 import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsManager;
 import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsSerializable;
 import org.eclipse.cdt.core.language.settings.providers.ScannerDiscoveryLegacySupport;
+import org.eclipse.cdt.core.model.ILanguage;
+import org.eclipse.cdt.core.model.LanguageManager;
 import org.eclipse.cdt.core.settings.model.ICConfigurationDescription;
 import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
 import org.eclipse.cdt.core.settings.model.ICProjectDescription;
+import org.eclipse.cdt.core.settings.model.ICSettingEntry;
 import org.eclipse.cdt.internal.core.XmlUtil;
+import org.eclipse.cdt.internal.core.settings.model.CConfigurationSpecSettings;
+import org.eclipse.cdt.internal.core.settings.model.CProjectDescriptionManager;
+import org.eclipse.cdt.internal.core.settings.model.IInternalCCfgInfo;
 import org.eclipse.core.filesystem.URIUtil;
+import org.eclipse.core.resources.IContainer;
 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IFolder;
 import org.eclipse.core.resources.IProject;
 import org.eclipse.core.resources.IResource;
+import org.eclipse.core.resources.IWorkspaceRoot;
+import org.eclipse.core.resources.ResourcesPlugin;
 import org.eclipse.core.runtime.Assert;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IPath;
 import org.eclipse.core.runtime.IStatus;
+import org.eclipse.core.runtime.ListenerList;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.core.runtime.jobs.ILock;
 import org.eclipse.core.runtime.jobs.Job;
@@ -61,11 +71,15 @@ public class LanguageSettingsProvidersSerializer {
 	private static final String ELEM_CONFIGURATION = "configuration"; //$NON-NLS-1$
 	private static final String ELEM_PROVIDER = "provider"; //$NON-NLS-1$
 	private static final String ELEM_PROVIDER_REFERENCE = "provider-reference"; //$NON-NLS-1$
+	
 	private static ILock serializingLock = Job.getJobManager().newLock();
+	
 	/** Cache of globally available providers to be consumed by calling clients */
 	private static Map<String, ILanguageSettingsProvider> rawGlobalWorkspaceProviders = new HashMap<String, ILanguageSettingsProvider>();
 	private static Map<String, ILanguageSettingsProvider> globalWorkspaceProviders = new HashMap<String, ILanguageSettingsProvider>();
 
+	private static ListenerList fLanguageSettingsChangeListeners = new ListenerList(ListenerList.IDENTITY);
+
 	private static class ListenerAssociation {
 		private ICListenerRegisterer listener;
 		private ICConfigurationDescription cfgDescription;
@@ -161,6 +175,75 @@ public class LanguageSettingsProvidersSerializer {
 		}
 	}
 
+	private static class LanguageSettingsChangeEvent implements ILanguageSettingsChangeEvent {
+		private String projectName = null;
+		private Map<String /*cfg*/, LanguageSettingsDelta> deltaMap = new HashMap<String, LanguageSettingsDelta>();
+		
+		private IResource[] resources = null;
+
+		/**
+		 * The act of creating event resets internal delta count in configuration state.
+		 * That implies that when the event is retrieved it must be fired or delta will go missing.
+		 * That side effect is here to ensure atomic processing of firing & resetting the delta.
+		 */
+		public LanguageSettingsChangeEvent(ICProjectDescription prjDescription) {
+			Assert.isTrue(prjDescription.isReadOnly());
+
+			projectName = prjDescription.getName();
+			ICConfigurationDescription[] cfgDescriptions = prjDescription.getConfigurations();
+			for (ICConfigurationDescription cfgDescription : cfgDescriptions) {
+				if (cfgDescription instanceof IInternalCCfgInfo) {
+					CConfigurationSpecSettings specSettings = null;
+					try {
+						specSettings = ((IInternalCCfgInfo) cfgDescription).getSpecSettings();
+					} catch (CoreException e) {
+						CCorePlugin.log(e);
+					}
+					if (specSettings != null) {
+						LanguageSettingsDelta delta = specSettings.dropDelta();
+						if (delta != null)
+							deltaMap.put(cfgDescription.getId(), delta);
+					} else {
+						IStatus ss = new Status(IStatus.ERROR, CCorePlugin.PLUGIN_ID, "Internal error: Missing specSettings for " + cfgDescription.getClass().getSimpleName());
+						CCorePlugin.log(new Status(IStatus.ERROR, CCorePlugin.PLUGIN_ID, ss.getMessage(), new CoreException(ss)));
+					}
+				}
+				
+			}
+		}
+
+		public String getProjectName() {
+			return projectName;
+		}
+
+		public String[] getConfigurationDescriptionIds() {
+			String[] ids = deltaMap.keySet().toArray(new String[deltaMap.size()]);
+			return ids;
+		}
+
+		public IResource[] getResources(String cfgDescriptionId) {
+			if (resources == null) {
+				LanguageSettingsDelta delta = deltaMap.get(cfgDescriptionId);
+				if (delta == null) {
+					resources = new IResource[0];
+				} else {
+					IProject project = ResourcesPlugin.getWorkspace().getRoot().getProject(projectName);
+					ICProjectDescription prjDescription = CProjectDescriptionManager.getInstance().getProjectDescription(project, false);
+					ICConfigurationDescription cfgDescription = prjDescription.getDefaultSettingConfiguration();
+					resources = delta.getChangedResources(project, cfgDescription).toArray(new IResource[0]);
+				}
+			}
+			
+			return resources;
+		}
+		
+		@Override
+		public String toString() {
+			return "LanguageSettingsChangeEvent for project=[" + getProjectName() + "]"
+					+ ", configurations=" + deltaMap.keySet()
+				;
+		}
+	}
 
 	/** static initializer */
 	static {
@@ -261,24 +344,66 @@ public class LanguageSettingsProvidersSerializer {
 		rawGlobalWorkspaceProviders = rawWorkspaceProviders;
 	}
 
+	private static List<LanguageSettingsChangeEvent> createLanguageLettingsChangeEvents(List<LanguageSettingsSerializable> serializableProviders) {
+		List<LanguageSettingsChangeEvent> events = new ArrayList<LanguageSettingsProvidersSerializer.LanguageSettingsChangeEvent>();
+		
+		List<String> serializableIds = new ArrayList<String>();
+		for (LanguageSettingsSerializable provider : serializableProviders) {
+			serializableIds.add(provider.getId());
+		}
+
+		IWorkspaceRoot root = ResourcesPlugin.getWorkspace().getRoot();
+		IProject[] projects = root.getProjects();
+projects:
+		for (IProject project : projects) {
+			if (project.isAccessible()) {
+				ICProjectDescription prjDescription = CCorePlugin.getDefault().getProjectDescription(project, false);
+				if (prjDescription != null) {
+					ICConfigurationDescription[] cfgDescriptions = prjDescription.getConfigurations();
+					for (ICConfigurationDescription cfgDescription : cfgDescriptions) {
+						for (ILanguageSettingsProvider provider : cfgDescription.getLanguageSettingProviders()) {
+							if (isWorkspaceProvider(provider) && serializableIds.contains(provider.getId())) {
+								LanguageSettingsChangeEvent event = new LanguageSettingsChangeEvent(prjDescription);
+								if (event.getConfigurationDescriptionIds().length > 0) {
+									events.add(event);
+								}
+								continue projects;
+							}
+						}
+					}
+				}
+			}
+			
+		}
+		
+		return events;
+	}
+
 	public static void serializeLanguageSettingsWorkspace() throws CoreException {
+		// AG TODO - remove the log
+		CCorePlugin.log(new Status(IStatus.WARNING, CCorePlugin.PLUGIN_ID, IStatus.OK,
+				"LanguageSettingsProvidersSerializer.serializeLanguageSettingsWorkspace()", new Exception()));
+		
 		URI uriStoreWsp = getStoreInWorkspaceArea(STORAGE_WORKSPACE_LANGUAGE_SETTINGS);
-		List<LanguageSettingsSerializable> serializableExtensionProviders = new ArrayList<LanguageSettingsSerializable>();
+		List<LanguageSettingsSerializable> serializableWorkspaceProviders = new ArrayList<LanguageSettingsSerializable>();
 		for (ILanguageSettingsProvider provider : rawGlobalWorkspaceProviders.values()) {
 			if (provider instanceof LanguageSettingsSerializable) {
 				// serialize all editable providers which are different from corresponding extension
 				// and serialize all serializable ones that are not editable (those are singletons and we don't know whether they changed)
 				if (!(provider instanceof ILanguageSettingsEditableProvider) || !LanguageSettingsExtensionManager.equalsExtensionProvider(provider)) {
-					serializableExtensionProviders.add((LanguageSettingsSerializable)provider);
+					serializableWorkspaceProviders.add((LanguageSettingsSerializable)provider);
 				}
 			}
 		}
 		try {
-			if (serializableExtensionProviders.isEmpty()) {
+			List<LanguageSettingsChangeEvent> events = null;
+			if (serializableWorkspaceProviders.isEmpty()) {
 				java.io.File fileStoreWsp = new java.io.File(uriStoreWsp);
-				serializingLock.acquire();
 				try {
+					serializingLock.acquire();
 					fileStoreWsp.delete();
+					// manufacture events while inside the lock
+					events = createLanguageLettingsChangeEvents(serializableWorkspaceProviders);
 				} finally {
 					serializingLock.release();
 				}
@@ -287,17 +412,23 @@ public class LanguageSettingsProvidersSerializer {
 				Element rootElement = XmlUtil.appendElement(doc, ELEM_PLUGIN);
 				Element elementExtension = XmlUtil.appendElement(rootElement, ELEM_EXTENSION, new String[] {ATTR_POINT, LanguageSettingsExtensionManager.PROVIDER_EXTENSION_FULL_ID});
 	
-				for (LanguageSettingsSerializable provider : serializableExtensionProviders) {
+				for (LanguageSettingsSerializable provider : serializableWorkspaceProviders) {
 					provider.serialize(elementExtension);
 				}
 	
-				serializingLock.acquire();
 				try {
+					serializingLock.acquire();
 					XmlUtil.serializeXml(doc, uriStoreWsp);
+					// manufacture events while inside the lock
+					events = createLanguageLettingsChangeEvents(serializableWorkspaceProviders);
 				} finally {
 					serializingLock.release();
 				}
 			}
+			// notify the listeners outside the lock
+			for (LanguageSettingsChangeEvent event : events) {
+				notifyLanguageSettingsChangeListeners(event);
+			}
 
 		} catch (Exception e) {
 			CCorePlugin.log("Internal error while trying to serialize language settings", e); //$NON-NLS-1$
@@ -414,6 +545,10 @@ public class LanguageSettingsProvidersSerializer {
 
 	public static void serializeLanguageSettings(ICProjectDescription prjDescription) throws CoreException {
 		IProject project = prjDescription.getProject();
+		// AG TODO - remove the log
+		CCorePlugin.log(new Status(IStatus.WARNING, CCorePlugin.PLUGIN_ID, IStatus.OK,
+				"LanguageSettingsProvidersSerializer.serializeLanguageSettings() for " + project, new Exception()));
+		
 		try {
 			// Document to store in project area
 			Document docStorePrj = XmlUtil.newDocument();
@@ -422,26 +557,37 @@ public class LanguageSettingsProvidersSerializer {
 			Document docStoreWsp = XmlUtil.newDocument();
 			Element projectElementStoreWsp = XmlUtil.appendElement(docStoreWsp, ELEM_PROJECT);
 
-			serializeLanguageSettingsInternal(projectElementStorePrj, projectElementStoreWsp, prjDescription);
-
-			IFile fileStorePrj = getStoreInProjectArea(project);
 			// The project store should not be absent. Absent store means legacy project, not 0 providers.
-			XmlUtil.serializeXml(docStorePrj, fileStorePrj);
+			IFile fileStorePrj = getStoreInProjectArea(project);
+			
+			URI uriStoreWsp = getStoreInWorkspaceArea(project.getName()+'.'+STORAGE_WORKSPACE_LANGUAGE_SETTINGS);
+			LanguageSettingsChangeEvent event = null;
 
-			URI uriStoreWsp = null;
-			boolean isWorkspaceStoreEmpty = projectElementStoreWsp.getChildNodes().getLength() == 0;
-			uriStoreWsp = getStoreInWorkspaceArea(project.getName()+'.'+STORAGE_WORKSPACE_LANGUAGE_SETTINGS);
-			serializingLock.acquire();
 			try {
+				serializingLock.acquire();
+
+				// Note that need for serialization may exist even if LSE event delta is empty,
+				// as number or properties of providers may differ
+				serializeLanguageSettingsInternal(projectElementStorePrj, projectElementStoreWsp, prjDescription);
+				XmlUtil.serializeXml(docStorePrj, fileStorePrj);
+
 				// project-specific location in workspace area
+				boolean isWorkspaceStoreEmpty = projectElementStoreWsp.getChildNodes().getLength() == 0;
 				if (!isWorkspaceStoreEmpty) {
 					XmlUtil.serializeXml(docStoreWsp, uriStoreWsp);
 				} else {
 					new java.io.File(uriStoreWsp).delete();
 				}
+				
+				// manufacture the event only if serialization was successful
+				event = new LanguageSettingsChangeEvent(prjDescription);
 			} finally {
 				serializingLock.release();
 			}
+			// notify the listeners outside the lock
+			if (event.getConfigurationDescriptionIds().length > 0) {
+				notifyLanguageSettingsChangeListeners(event);
+			}
 
 		} catch (Exception e) {
 			IStatus s = new Status(IStatus.ERROR, CCorePlugin.PLUGIN_ID, "Internal error while trying to serialize language settings", e);
@@ -510,8 +656,16 @@ public class LanguageSettingsProvidersSerializer {
 			}
 
 			ICConfigurationDescription cfgDescription = prjDescription.getConfigurationById(cfgId);
-			if (cfgDescription!=null)
+			if (cfgDescription!=null) {
 				cfgDescription.setLanguageSettingProviders(providers);
+				if (cfgDescription instanceof IInternalCCfgInfo) {
+					try {
+						((IInternalCCfgInfo) cfgDescription).getSpecSettings().dropDelta();
+					} catch (CoreException e) {
+						CCorePlugin.log(e);
+					}
+				}
+			}
 		}
 	}
 
@@ -839,8 +993,9 @@ public class LanguageSettingsProvidersSerializer {
 				try {
 					provider = ((ILanguageSettingsEditableProvider) provider).clone();
 				} catch (CloneNotSupportedException e) {
-					IStatus status = new Status(IStatus.ERROR, CCorePlugin.PLUGIN_ID, "Not able to clone provider " + provider.getClass());
+					IStatus status = new Status(IStatus.ERROR, CCorePlugin.PLUGIN_ID, Status.OK,
-					CCorePlugin.log(new CoreException(status));
+							"Not able to clone provider " + provider.getClass(), e);
+					CCorePlugin.log(status);
 				}
 			}
 			newProviders.add(provider);
@@ -848,4 +1003,300 @@ public class LanguageSettingsProvidersSerializer {
 		return new ArrayList<ILanguageSettingsProvider>(newProviders);
 	}
 	
+	/**
+	 * Adds a listener that will be notified of changes in language settings.
+	 * 
+	 * @param listener the ILanguageMappingChangeListener to add
+	 */
+	public static void registerLanguageSettingsChangeListener(ILanguageSettingsChangeListener listener) {
+		fLanguageSettingsChangeListeners.add(listener);
+	}
+	
+	/**
+	 * Removes a language settings change listener.
+	 * 
+	 * @param listener the ILanguageMappingChangeListener to remove.
+	 */
+	public static void unregisterLanguageSettingsChangeListener(ILanguageSettingsChangeListener listener) {
+		fLanguageSettingsChangeListeners.remove(listener);
+	}
+
+	/**
+	 * Notifies all language settings change listeners of a change.
+	 * 
+	 * @param event the ILanguageSettingsChangeEvent event to be broadcast.
+	 */
+	public static void notifyLanguageSettingsChangeListeners(ILanguageSettingsChangeEvent event) {
+		// AG TODO - remove the log
+		CCorePlugin.log(new Status(IStatus.WARNING, CCorePlugin.PLUGIN_ID, IStatus.OK,
+				"Firing " + event, new Exception()));
+
+		Object[] listeners = fLanguageSettingsChangeListeners.getListeners();
+		for (Object obj : listeners) {
+			ILanguageSettingsChangeListener listener = (ILanguageSettingsChangeListener) obj;
+			listener.handleEvent(event);
+		}
+	}
+
+	private static List<ICLanguageSettingEntry> safeGetSettingEntries(ILanguageSettingsProvider provider,
+			ICConfigurationDescription cfgDescription, IResource rc, String languageId) {
+		
+		try {
+			return provider.getSettingEntries(cfgDescription, rc, languageId);
+		} catch (Throwable e) {
+			String cfgId = cfgDescription!=null ? cfgDescription.getId() : null;
+			String msg = "Exception in provider "+provider.getId()+": getSettingEntries("+cfgId+", "+rc+", "+languageId+")";
+			CCorePlugin.log(msg, e);
+			// return empty array to prevent climbing up the resource tree 
+			return new ArrayList<ICLanguageSettingEntry>(0);
+		}
+	}
+
+	/**
+	 * Returns the list of setting entries of the given provider
+	 * for the given configuration description, resource and language.
+	 * This method reaches to the parent folder of the resource recursively
+	 * in case the resource does not define the entries for the given provider.
+	 * 
+	 * @param provider - language settings provider.
+	 * @param cfgDescription - configuration description.
+	 * @param rc - resource such as file or folder.
+	 * @param languageId - language id.
+	 * 
+	 * @return the list of setting entries. Never returns {@code null}
+	 *     although individual providers mandated to return {@code null} if no settings defined.
+	 */
+	public static List<ICLanguageSettingEntry> getSettingEntriesUpResourceTree(ILanguageSettingsProvider provider, ICConfigurationDescription cfgDescription, IResource rc, String languageId) {
+		Assert.isTrue( !(rc instanceof IWorkspaceRoot) );
+		if (provider!=null) {
+			List<ICLanguageSettingEntry> entries = safeGetSettingEntries(provider, cfgDescription, rc, languageId);
+			if (entries!=null) {
+				return new ArrayList<ICLanguageSettingEntry>(entries);
+			}
+			if (rc!=null) {
+				IResource parentFolder = (rc instanceof IProject) ? null : rc.getParent();
+				if (parentFolder!=null) {
+					return getSettingEntriesUpResourceTree(provider, cfgDescription, parentFolder, languageId);
+				}
+				// if out of parent resources - get default entries for the applicable language scope
+				entries = safeGetSettingEntries(provider, null, null, languageId);
+				if (entries!=null) {
+					return new ArrayList<ICLanguageSettingEntry>(entries);
+				}
+			}
+		}
+	
+		return new ArrayList<ICLanguageSettingEntry>(0);
+	}
+
+	/**
+	 * Builds for the provider a nice looking resource tree to present hierarchical view to the user.
+	 * Note that it is not advisable to "compact" the tree because of potential loss of information
+	 * which is especially important during partial or incremental builds.
+	 * 
+	 * @param provider - language settings provider to build the tree for.
+	 * @param cfgDescription - configuration description.
+	 * @param languageId - language ID.
+	 * @param folder - container where the tree roots.
+	 */
+	public static void buildResourceTree(LanguageSettingsSerializable provider, ICConfigurationDescription cfgDescription, String languageId, IContainer folder) {
+		IResource[] members = null;
+		try {
+			members = folder.members();
+		} catch (Exception e) {
+			CCorePlugin.log(e);
+		}
+		if (members==null)
+			return;
+		
+		for (IResource rc : members) {
+			if (rc instanceof IContainer) {
+				buildResourceTree(provider, cfgDescription, languageId, (IContainer) rc);
+			}
+		}
+	
+		int rcNumber = members.length;
+		
+		Map<List<ICLanguageSettingEntry>, Integer> listMap = new HashMap<List<ICLanguageSettingEntry>, Integer>();
+		
+		// on the first pass find majority entries
+		List<ICLanguageSettingEntry> majorityEntries = null;
+		List<ICLanguageSettingEntry> candidate = null;
+		int candidateCount = 0;
+		for (IResource rc : members) {
+			if (!isLanguageInScope(rc, cfgDescription, languageId)) {
+				rcNumber--;
+			} else {
+				List<ICLanguageSettingEntry> entries = provider.getSettingEntries(null, rc, languageId);
+				if (entries==null && rc instanceof IContainer) {
+					rcNumber--;
+				} else {
+					Integer count = listMap.get(entries);
+					if (count==null) {
+						count = 0;
+					}
+					count++;
+					
+					if (count>candidateCount) {
+						candidateCount = count;
+						candidate = entries;
+					}
+					
+					listMap.put(entries, count);
+				}
+			}
+	
+			if (candidateCount > rcNumber/2) {
+				majorityEntries = candidate;
+				break;
+			}
+		}
+		
+		if (majorityEntries!=null) {
+			provider.setSettingEntries(cfgDescription, folder, languageId, majorityEntries);
+		}
+		
+		// second pass - assign the entries to the folders
+		for (IResource rc : members) {
+			List<ICLanguageSettingEntry> entries = provider.getSettingEntries(null, rc, languageId);
+			if (entries!=null && entries==majorityEntries) {
+				if (!(rc instanceof IFile)) { // preserve information which files were collected
+					provider.setSettingEntries(cfgDescription, rc, languageId, null);
+				}
+			}
+		}
+	}
+
+	private static boolean isLanguageInScope(IResource rc, ICConfigurationDescription cfgDescription, String languageId) {
+		if (rc instanceof IFile) {
+			ILanguage lang = null;
+			try {
+				lang = LanguageManager.getInstance().getLanguageForFile((IFile) rc, cfgDescription);
+			} catch (CoreException e) {
+				CCorePlugin.log("Error loading language settings providers extensions", e); //$NON-NLS-1$
+			}
+			if (lang==null || (languageId!=null && !languageId.equals(lang.getId()))) {
+				return false;
+			}
+		}
+		return true;
+	}
+
+	private static boolean checkBit(int flags, int bit) {
+		return (flags & bit) == bit;
+	}
+
+	/**
+	 * Returns the list of setting entries of a certain kind (such as include paths)
+	 * for the given configuration description, resource and language. This is a
+	 * combined list for all providers taking into account settings of parent folder
+	 * if settings for the given resource are not defined.
+	 * 
+	 * @param cfgDescription - configuration description.
+	 * @param rc - resource such as file or folder.
+	 * @param languageId - language id.
+	 * @param kind - kind of language settings entries, such as
+	 *     {@link ICSettingEntry#INCLUDE_PATH} etc. This is a binary flag
+	 *     and it is possible to specify composite kind.
+	 *     Use {@link ICSettingEntry#ALL} to get all kinds.
+	 * @param checkLocality - specifies if parameter {@code isLocal} should be considered.
+	 * @param isLocal - {@code true} if "local" entries should be provided and
+	 *     {@code false} for "system" entries. This makes sense for include paths where
+	 *     [#include "..."] is "local" and [#include <...>] is system.
+	 * 
+	 * @return the list of setting entries found.
+	 */
+	private static List<ICLanguageSettingEntry> getSettingEntriesByKind(ICConfigurationDescription cfgDescription,
+			IResource rc, String languageId, int kind, boolean checkLocality, boolean isLocal) {
+	
+		List<ICLanguageSettingEntry> entries = new ArrayList<ICLanguageSettingEntry>();
+		List<String> alreadyAdded = new ArrayList<String>();
+	
+		List<ILanguageSettingsProvider> providers = cfgDescription.getLanguageSettingProviders();
+		for (ILanguageSettingsProvider provider: providers) {
+			List<ICLanguageSettingEntry> providerEntries = getSettingEntriesUpResourceTree(provider, cfgDescription, rc, languageId);
+			for (ICLanguageSettingEntry entry : providerEntries) {
+				if (entry!=null) {
+					String entryName = entry.getName();
+					boolean isRightKind = (entry.getKind() & kind) != 0;
+					// Only first entry is considered
+					// Entry flagged as "UNDEFINED" prevents adding entry with the same name down the line
+					if (isRightKind && !alreadyAdded.contains(entryName)) {
+						int flags = entry.getFlags();
+						boolean isRightLocal = !checkLocality || (checkBit(flags, ICSettingEntry.LOCAL) == isLocal);
+						if (isRightLocal) {
+							if (!checkBit(flags, ICSettingEntry.UNDEFINED)) {
+								entries.add(entry);
+							}
+							alreadyAdded.add(entryName);
+						}
+					}
+				}
+			}
+		}
+	
+		return entries;
+	}
+
+	/**
+	 * Returns the list of setting entries of a certain kind (such as include paths)
+	 * for the given configuration description, resource and language. This is a
+	 * combined list for all providers taking into account settings of parent folder
+	 * if settings for the given resource are not defined. For include paths both
+	 * local (#include "...") and system (#include <...>) entries are returned.
+	 * 
+	 * @param cfgDescription - configuration description.
+	 * @param rc - resource such as file or folder.
+	 * @param languageId - language id.
+	 * @param kind - kind of language settings entries, such as
+	 *     {@link ICSettingEntry#INCLUDE_PATH} etc. This is a binary flag
+	 *     and it is possible to specify composite kind.
+	 *     Use {@link ICSettingEntry#ALL} to get all kinds.
+	 * 
+	 * @return the list of setting entries.
+	 */
+	public static List<ICLanguageSettingEntry> getSettingEntriesByKind(ICConfigurationDescription cfgDescription, IResource rc, String languageId, int kind) {
+		return getSettingEntriesByKind(cfgDescription, rc, languageId, kind, /* checkLocality */ false, /* isLocal */ false);
+	}
+
+	/**
+	 * Returns the list of "system" (such as [#include <...>]) setting entries of a certain kind 
+	 * for the given configuration description, resource and language. This is a
+	 * combined list for all providers taking into account settings of parent folder
+	 * if settings for the given resource are not defined.
+	 * 
+	 * @param cfgDescription - configuration description.
+	 * @param rc - resource such as file or folder.
+	 * @param languageId - language id.
+	 * @param kind - kind of language settings entries, such as
+	 *     {@link ICSettingEntry#INCLUDE_PATH} etc. This is a binary flag
+	 *     and it is possible to specify composite kind.
+	 *     Use {@link ICSettingEntry#ALL} to get all kinds.
+	 * 
+	 * @return the list of setting entries.
+	 */
+	public static List<ICLanguageSettingEntry> getSystemSettingEntriesByKind(ICConfigurationDescription cfgDescription, IResource rc, String languageId, int kind) {
+		return getSettingEntriesByKind(cfgDescription, rc, languageId, kind, /* checkLocality */ true, /* isLocal */ false);
+	}
+
+	/**
+	 * Returns the list of "local" (such as [#include "..."]) setting entries of a certain kind 
+	 * for the given configuration description, resource and language. This is a
+	 * combined list for all providers taking into account settings of parent folder
+	 * if settings for the given resource are not defined.
+	 * 
+	 * @param cfgDescription - configuration description.
+	 * @param rc - resource such as file or folder.
+	 * @param languageId - language id.
+	 * @param kind - kind of language settings entries, such as
+	 *     {@link ICSettingEntry#INCLUDE_PATH} etc. This is a binary flag
+	 *     and it is possible to specify composite kind.
+	 *     Use {@link ICSettingEntry#ALL} to get all kinds.
+	 * 
+	 * @return the list of setting entries.
+	 */
+	public static List<ICLanguageSettingEntry> getLocalSettingEntriesByKind(ICConfigurationDescription cfgDescription, IResource rc, String languageId, int kind) {
+		return getSettingEntriesByKind(cfgDescription, rc, languageId, kind, /* checkLocality */ true, /* isLocal */ true);
+	}
+
 }

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/language/settings/providers/LanguageSettingsScannerInfoProvider.java

@@ -80,23 +80,23 @@ public class LanguageSettingsScannerInfoProvider implements IScannerInfoProvider
 		LinkedHashSet<ICLanguageSettingEntry> macroEntries = new LinkedHashSet<ICLanguageSettingEntry>();
 
 		for (String langId : languageIds) {
-			List<ICLanguageSettingEntry> incSys = LanguageSettingsExtensionManager.getSystemSettingEntriesByKind(cfgDescription, rc, langId,
+			List<ICLanguageSettingEntry> incSys = LanguageSettingsProvidersSerializer.getSystemSettingEntriesByKind(cfgDescription, rc, langId,
 					ICSettingEntry.INCLUDE_PATH);
 			includePathEntries.addAll(incSys);
 
-			List<ICLanguageSettingEntry> incLocal = LanguageSettingsExtensionManager.getLocalSettingEntriesByKind(cfgDescription, rc, langId,
+			List<ICLanguageSettingEntry> incLocal = LanguageSettingsProvidersSerializer.getLocalSettingEntriesByKind(cfgDescription, rc, langId,
 					ICSettingEntry.INCLUDE_PATH);
 			includePathLocalEntries.addAll(incLocal);
 
-			List<ICLanguageSettingEntry> incFiles = LanguageSettingsExtensionManager.getSettingEntriesByKind(cfgDescription, rc, langId,
+			List<ICLanguageSettingEntry> incFiles = LanguageSettingsProvidersSerializer.getSettingEntriesByKind(cfgDescription, rc, langId,
 					ICSettingEntry.INCLUDE_FILE);
 			includeFileEntries.addAll(incFiles);
 
-			List<ICLanguageSettingEntry> macroFiles = LanguageSettingsExtensionManager.getSettingEntriesByKind(cfgDescription, rc, langId,
+			List<ICLanguageSettingEntry> macroFiles = LanguageSettingsProvidersSerializer.getSettingEntriesByKind(cfgDescription, rc, langId,
 					ICSettingEntry.MACRO_FILE);
 			macroFileEntries.addAll(macroFiles);
 
-			List<ICLanguageSettingEntry> macros = LanguageSettingsExtensionManager.getSettingEntriesByKind(cfgDescription, rc, langId,
+			List<ICLanguageSettingEntry> macros = LanguageSettingsProvidersSerializer.getSettingEntriesByKind(cfgDescription, rc, langId,
 					ICSettingEntry.MACRO);
 			macroEntries.addAll(macros);
 		}

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/language/settings/providers/LanguageSettingsStorage.java

@@ -0,0 +1,378 @@
+package org.eclipse.cdt.internal.core.language.settings.providers;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+
+import org.eclipse.cdt.core.settings.model.ICConfigurationDescription;
+import org.eclipse.cdt.core.settings.model.ICLanguageSettingEntry;
+import org.eclipse.cdt.core.settings.model.ICSettingEntry;
+import org.eclipse.cdt.core.settings.model.util.CDataUtil;
+import org.eclipse.cdt.core.settings.model.util.LanguageSettingEntriesSerializer;
+import org.eclipse.cdt.internal.core.XmlUtil;
+import org.eclipse.cdt.internal.core.parser.util.WeakHashSet;
+import org.eclipse.core.resources.IResource;
+import org.w3c.dom.Element;
+import org.w3c.dom.Node;
+import org.w3c.dom.NodeList;
+
+public class LanguageSettingsStorage {
+	private static final String ELEM_LANGUAGE = "language"; //$NON-NLS-1$
+	private static final String ATTR_LANGUAGE_ID = "id"; //$NON-NLS-1$
+	private static final String ELEM_RESOURCE = "resource"; //$NON-NLS-1$
+	private static final String ATTR_PROJECT_PATH = "project-relative-path"; //$NON-NLS-1$
+
+	private static final String ELEM_ENTRY = "entry"; //$NON-NLS-1$
+	private static final String ATTR_KIND = "kind"; //$NON-NLS-1$
+	private static final String ATTR_NAME = "name"; //$NON-NLS-1$
+	private static final String ATTR_VALUE = "value"; //$NON-NLS-1$
+	private static final String ELEM_FLAG = "flag"; //$NON-NLS-1$
+
+	/**
+	 * Storage to keep settings entries. Note that it is not necessary to keep configuration in the maps
+	 * as the configuration is always the one provider belongs to.
+	 */
+	private Map<String, // languageId
+				Map<String, // resource project path
+					List<ICLanguageSettingEntry>>> fStorage = new HashMap<String, Map<String, List<ICLanguageSettingEntry>>>();
+
+	/**
+	 * Pool of LSE lists implemented as WeakHashSet. That allows to gain memory savings
+	 * at the expense of CPU time. WeakHashSet handles garbage collection when a list is not
+	 * referenced anywhere else. See JavaDoc {@link java.lang.ref.WeakReference} about weak reference objects.
+	 */
+	private static WeakHashSet<List<ICLanguageSettingEntry>> listPool = new WeakHashSet<List<ICLanguageSettingEntry>>() {
+		@Override
+		public synchronized List<ICLanguageSettingEntry> add(List<ICLanguageSettingEntry> list) {
+			return super.add(list);
+		}
+
+	};
+
+	/**
+	 * <br> Note that this list is <b>unmodifiable</b>. To modify the list copy it, change and use
+	 * {@link #setSettingEntries(ICConfigurationDescription, IResource, String, List)}.
+	 *
+	 */
+	public List<ICLanguageSettingEntry> getSettingEntries(ICConfigurationDescription cfgDescription, IResource rc, String languageId) {
+		List<ICLanguageSettingEntry> entries = null;
+		Map<String, List<ICLanguageSettingEntry>> langMap = fStorage.get(languageId);
+		if (langMap!=null) {
+			String rcProjectPath = rc!=null ? rc.getProjectRelativePath().toString() : null;
+			entries = langMap.get(rcProjectPath);
+		}
+		return entries;
+	}
+
+	/**
+	 * Some providers may collect entries in pretty much random order. For the purposes of
+	 * predictability, UI usability and efficient storage the entries are sorted by kinds
+	 * and secondary by name for kinds where the secondary order is not significant.
+	 *
+	 * @param entries - list of entries to sort.
+	 * @return - sorted entries.
+	 */
+	private List<ICLanguageSettingEntry> sortEntries(List<ICLanguageSettingEntry> entries) {
+		List<ICLanguageSettingEntry> sortedEntries = new ArrayList<ICLanguageSettingEntry>(entries);
+		Collections.sort(sortedEntries, new Comparator<ICLanguageSettingEntry>(){
+			/**
+			 * This comparator sorts by kinds first and the macros are sorted additionally by name.
+			 */
+			public int compare(ICLanguageSettingEntry entry0, ICLanguageSettingEntry entry1) {
+				int kind0 = entry0.getKind();
+				int kind1 = entry1.getKind();
+				if (kind0==ICSettingEntry.MACRO && kind1==ICSettingEntry.MACRO) {
+					return entry0.getName().compareTo(entry1.getName());
+				}
+
+				return kind0 - kind1;
+			}});
+
+		return sortedEntries;
+	}
+
+	/**
+	 * 
+	 */
+	public void setSettingEntries(String rcProjectPath, String languageId, List<ICLanguageSettingEntry> entries) {
+		synchronized (fStorage) {
+			if (entries!=null) {
+				Map<String, List<ICLanguageSettingEntry>> langMap = fStorage.get(languageId);
+				if (langMap==null) {
+					langMap = new HashMap<String, List<ICLanguageSettingEntry>>();
+					fStorage.put(languageId, langMap);
+				}
+				List<ICLanguageSettingEntry> sortedEntries = listPool.add(Collections.unmodifiableList(sortEntries(entries)));
+				langMap.put(rcProjectPath, sortedEntries);
+			} else {
+				// do not keep nulls in the tables
+				Map<String, List<ICLanguageSettingEntry>> langMap = fStorage.get(languageId);
+				if (langMap!=null) {
+					langMap.remove(rcProjectPath);
+					if (langMap.size()==0) {
+						fStorage.remove(languageId);
+					}
+				}
+			}
+		}
+	}
+
+	/**
+	 * @return {@code true} if the provider does not keep any settings yet or {@code false} if there are some.
+	 */
+	public boolean isEmpty() {
+		return fStorage.isEmpty();
+	}
+	
+	/**
+	 * Clear all the entries for all configurations, all resources and all languages.
+	 */
+	public void clear() {
+		synchronized (fStorage) {
+			fStorage.clear();
+		}
+	}
+
+	/**
+	 * Serialize the provider entries under parent XML element.
+	 * @param elementProvider - element where to serialize the entries.
+	 */
+	public void serializeEntries(Element elementProvider) {
+		synchronized (fStorage) {
+			for (Entry<String, Map<String, List<ICLanguageSettingEntry>>> entryLang : fStorage.entrySet()) {
+				serializeLanguage(elementProvider, entryLang);
+			}
+		}
+	}
+
+	/**
+	 * Serialize the provider entries for a given language list.
+	 */
+	private void serializeLanguage(Element parentElement, Entry<String, Map<String, List<ICLanguageSettingEntry>>> entryLang) {
+		String langId = entryLang.getKey();
+		if (langId!=null) {
+			Element elementLanguage = XmlUtil.appendElement(parentElement, ELEM_LANGUAGE, new String[] {ATTR_LANGUAGE_ID, langId});
+			parentElement = elementLanguage;
+		}
+		for (Entry<String, List<ICLanguageSettingEntry>> entryRc : entryLang.getValue().entrySet()) {
+			serializeResource(parentElement, entryRc);
+		}
+	}
+
+	/**
+	 * Serialize the provider entries for a given resource list.
+	 */
+	private void serializeResource(Element parentElement, Entry<String, List<ICLanguageSettingEntry>> entryRc) {
+		String rcProjectPath = entryRc.getKey();
+		if (rcProjectPath!=null) {
+			Element elementRc = XmlUtil.appendElement(parentElement, ELEM_RESOURCE, new String[] {ATTR_PROJECT_PATH, rcProjectPath});
+			parentElement = elementRc;
+		}
+		serializeSettingEntries(parentElement, entryRc.getValue());
+	}
+
+	/**
+	 * Serialize given settings entries.
+	 */
+	private void serializeSettingEntries(Element parentElement, List<ICLanguageSettingEntry> settingEntries) {
+		for (ICLanguageSettingEntry entry : settingEntries) {
+			Element elementSettingEntry = XmlUtil.appendElement(parentElement, ELEM_ENTRY, new String[] {
+					ATTR_KIND, LanguageSettingEntriesSerializer.kindToString(entry.getKind()),
+					ATTR_NAME, entry.getName(),
+				});
+			switch(entry.getKind()) {
+			case ICSettingEntry.MACRO:
+				elementSettingEntry.setAttribute(ATTR_VALUE, entry.getValue());
+				break;
+//			case ICLanguageSettingEntry.LIBRARY_FILE:
+//				// TODO: sourceAttachment fields may need to be covered
+//				break;
+			}
+			int flags = entry.getFlags();
+			if (flags!=0) {
+				// Element elementFlag =
+				XmlUtil.appendElement(elementSettingEntry, ELEM_FLAG, new String[] {
+						ATTR_VALUE, LanguageSettingEntriesSerializer.composeFlagsString(entry.getFlags())
+					});
+			}
+		}
+	}
+
+	/**
+	 * Load provider entries from XML provider element.
+	 * @param providerNode - parent XML element <provider> where entries are defined.
+	 */
+	public void loadEntries(Element providerNode) {
+		List<ICLanguageSettingEntry> settings = new ArrayList<ICLanguageSettingEntry>();
+		NodeList nodes = providerNode.getChildNodes();
+		for (int i=0;i<nodes.getLength();i++) {
+			Node elementNode = nodes.item(i);
+			if(elementNode.getNodeType() != Node.ELEMENT_NODE)
+				continue;
+
+			if (ELEM_LANGUAGE.equals(elementNode.getNodeName())) {
+				loadLanguageElement(elementNode, null);
+			} else if (ELEM_RESOURCE.equals(elementNode.getNodeName())) {
+				loadResourceElement(elementNode, null, null);
+			} else if (ELEM_ENTRY.equals(elementNode.getNodeName())) {
+				ICLanguageSettingEntry entry = loadSettingEntry(elementNode);
+				if (entry!=null) {
+					settings.add(entry);
+				}
+			}
+		}
+		// set settings
+		if (settings.size()>0) {
+			setSettingEntries(null, null, settings);
+		}
+	}
+
+	/**
+	 * Load a setting entry from XML element.
+	 */
+	private ICLanguageSettingEntry loadSettingEntry(Node parentElement) {
+		String settingKind = XmlUtil.determineAttributeValue(parentElement, ATTR_KIND);
+		String settingName = XmlUtil.determineAttributeValue(parentElement, ATTR_NAME);
+	
+		NodeList flagNodes = parentElement.getChildNodes();
+		int flags = 0;
+		for (int i=0;i<flagNodes.getLength();i++) {
+			Node flagNode = flagNodes.item(i);
+			if(flagNode.getNodeType() != Node.ELEMENT_NODE || !ELEM_FLAG.equals(flagNode.getNodeName()))
+				continue;
+	
+			String settingFlags = XmlUtil.determineAttributeValue(flagNode, ATTR_VALUE);
+			int bitFlag = LanguageSettingEntriesSerializer.composeFlags(settingFlags);
+			flags |= bitFlag;
+	
+		}
+	
+		String settingValue = null;
+		int kind = LanguageSettingEntriesSerializer.stringToKind(settingKind);
+		if (kind == ICSettingEntry.MACRO)
+			settingValue = XmlUtil.determineAttributeValue(parentElement, ATTR_VALUE);
+		ICLanguageSettingEntry entry = (ICLanguageSettingEntry) CDataUtil.createEntry(kind, settingName, settingValue, null, flags);
+		return entry;
+	}
+
+	/**
+	 * Load entries defined in language element.
+	 */
+	private void loadLanguageElement(Node parentNode, String cfgId) {
+		String langId = XmlUtil.determineAttributeValue(parentNode, ATTR_LANGUAGE_ID);
+		if (langId.length()==0) {
+			langId=null;
+		}
+
+		List<ICLanguageSettingEntry> settings = new ArrayList<ICLanguageSettingEntry>();
+		NodeList nodes = parentNode.getChildNodes();
+		for (int i=0;i<nodes.getLength();i++) {
+			Node elementNode = nodes.item(i);
+			if(elementNode.getNodeType() != Node.ELEMENT_NODE)
+				continue;
+
+			if (ELEM_RESOURCE.equals(elementNode.getNodeName())) {
+				loadResourceElement(elementNode, cfgId, langId);
+			} else if (ELEM_ENTRY.equals(elementNode.getNodeName())) {
+				ICLanguageSettingEntry entry = loadSettingEntry(elementNode);
+				if (entry!=null) {
+					settings.add(entry);
+				}
+			}
+		}
+		// set settings
+		if (settings.size()>0) {
+			setSettingEntries(null, langId, settings);
+		}
+	}
+
+	/**
+	 * Load entries defined in resource element.
+	 */
+	private void loadResourceElement(Node parentNode, String cfgId, String langId) {
+		String rcProjectPath = XmlUtil.determineAttributeValue(parentNode, ATTR_PROJECT_PATH);
+
+		List<ICLanguageSettingEntry> settings = new ArrayList<ICLanguageSettingEntry>();
+		NodeList nodes = parentNode.getChildNodes();
+		for (int i=0;i<nodes.getLength();i++) {
+			Node elementNode = nodes.item(i);
+			if(elementNode.getNodeType() != Node.ELEMENT_NODE)
+				continue;
+
+			if (ELEM_ENTRY.equals(elementNode.getNodeName())) {
+				ICLanguageSettingEntry entry = loadSettingEntry(elementNode);
+				if (entry!=null) {
+					settings.add(entry);
+				}
+			}
+		}
+
+		// set settings
+		if (settings.size()>0) {
+			setSettingEntries(rcProjectPath, langId, settings);
+		}
+	}
+
+	/**
+	 * @noreference This method is not intended to be referenced by clients.
+	 * Warning: but if you use it make sure you synchronize on it while traversing.
+	 */
+	Map<String, Map<String, List<ICLanguageSettingEntry>>> getMapInternal() {
+		return fStorage;
+	}
+	/**
+	 * Clone storage for the entries. Copies references for lists of entries as a whole.
+	 * Note that is OK as the lists kept in storage are unmodifiable.
+	 */
+	public LanguageSettingsStorage cloneStorage() {
+		LanguageSettingsStorage storageClone = new LanguageSettingsStorage();
+		synchronized (fStorage) {
+			Set<Entry<String, Map<String, List<ICLanguageSettingEntry>>>> entrySetLang = fStorage.entrySet();
+			for (Entry<String, Map<String, List<ICLanguageSettingEntry>>> entryLang : entrySetLang) {
+				String langId = entryLang.getKey();
+				Map<String, List<ICLanguageSettingEntry>> mapRc = entryLang.getValue();
+				Map<String, List<ICLanguageSettingEntry>> mapRcClone = new HashMap<String, List<ICLanguageSettingEntry>>();
+				Set<Entry<String, List<ICLanguageSettingEntry>>> entrySetRc = mapRc.entrySet();
+				for (Entry<String, List<ICLanguageSettingEntry>> entryRc : entrySetRc) {
+					String rcProjectPath = entryRc.getKey();
+					List<ICLanguageSettingEntry> lsEntries = entryRc.getValue();
+					// don't need to clone entries, they are from the LSE pool
+					mapRcClone.put(rcProjectPath, lsEntries);
+				}
+				storageClone.fStorage.put(langId, mapRcClone);
+			}
+		}
+		return storageClone;
+	}
+
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((fStorage == null) ? 0 : fStorage.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		LanguageSettingsStorage other = (LanguageSettingsStorage) obj;
+		if (fStorage == null) {
+			if (other.fStorage != null)
+				return false;
+		} else if (!fStorage.equals(other.fStorage))
+			return false;
+		return true;
+	}
+
+}

core/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/settings/model/CConfigurationSpecSettings.java

@@ -24,6 +24,8 @@ import java.util.Set;
 
 import org.eclipse.cdt.core.CCorePlugin;
 import org.eclipse.cdt.core.language.settings.providers.ILanguageSettingsProvider;
+import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsManager;
+import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsSerializable;
 import org.eclipse.cdt.core.settings.model.CExternalSetting;
 import org.eclipse.cdt.core.settings.model.ICBuildSetting;
 import org.eclipse.cdt.core.settings.model.ICConfigExtensionReference;
@@ -41,7 +43,9 @@ import org.eclipse.cdt.internal.core.COwner;
 import org.eclipse.cdt.internal.core.COwnerConfiguration;
 import org.eclipse.cdt.internal.core.cdtvariables.StorableCdtVariables;
 import org.eclipse.cdt.internal.core.envvar.EnvironmentVariableManager;
+import org.eclipse.cdt.internal.core.language.settings.providers.LanguageSettingsDelta;
 import org.eclipse.cdt.internal.core.language.settings.providers.LanguageSettingsProvidersSerializer;
+import org.eclipse.cdt.internal.core.language.settings.providers.LanguageSettingsStorage;
 import org.eclipse.cdt.utils.envvar.StorableEnvironment;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.QualifiedName;
@@ -94,6 +98,8 @@ public class CConfigurationSpecSettings implements ICSettingsStorage{
 //	private Map fExternalSettingsProviderMap;
 
 	private List<ILanguageSettingsProvider> fLanguageSettingsProviders = new ArrayList<ILanguageSettingsProvider>(0);
+	private LinkedHashMap<String /*provider*/, LanguageSettingsStorage> lspPersistedState = new LinkedHashMap<String, LanguageSettingsStorage>();
+
 
 	private class DeltaSet {
 		public Set<ICConfigExtensionReference> extSet;
@@ -189,6 +195,10 @@ public class CConfigurationSpecSettings implements ICSettingsStorage{
 		copyExtensionInfo(base);
 		
 		fLanguageSettingsProviders = LanguageSettingsProvidersSerializer.cloneProviders(base.getLanguageSettingProviders());
+		for (String providerId : base.lspPersistedState.keySet()) {
+			LanguageSettingsStorage clone = base.lspPersistedState.get(providerId).cloneStorage();
+			lspPersistedState.put(providerId, clone);
+		}
 	}
 
 //	private void copyRefInfos(Map infosMap){
@@ -1011,4 +1021,40 @@ public class CConfigurationSpecSettings implements ICSettingsStorage{
 	public List<ILanguageSettingsProvider> getLanguageSettingProviders() {
 		return Collections.unmodifiableList(fLanguageSettingsProviders);
 	}
+
+	/**
+	 * Returns delta and atomically updates last persisted state to the new state.
+	 * That implies that the delta needs to be used to fire an event of it will
+	 * be lost.
+	 */
+	public LanguageSettingsDelta dropDelta() {
+		LanguageSettingsDelta languageSettingsDelta = null;
+		// newState gets shallow map first
+		LinkedHashMap<String, LanguageSettingsStorage> newStateShallow = new LinkedHashMap<String, LanguageSettingsStorage>();
+		for (ILanguageSettingsProvider provider : fLanguageSettingsProviders) {
+			if (LanguageSettingsManager.isWorkspaceProvider(provider)) {
+				provider = LanguageSettingsManager.getRawProvider(provider);
+			}
+			if (provider instanceof LanguageSettingsSerializable) {
+				LanguageSettingsStorage store = ((LanguageSettingsSerializable) provider).getStorageInternal();
+				if (!store.isEmpty()) {
+					newStateShallow.put(provider.getId(), store);
+				}
+			}
+		}
+		if (!newStateShallow.equals(lspPersistedState)) {
+			// do deep copy if the state needs to be saved
+			LinkedHashMap<String, LanguageSettingsStorage> newStateDeep = new LinkedHashMap<String, LanguageSettingsStorage>();
+			for (Entry<String, LanguageSettingsStorage> entry : newStateShallow.entrySet()) {
+				String providerId = entry.getKey();
+				LanguageSettingsStorage store = entry.getValue();
+				newStateDeep.put(providerId, store.cloneStorage());
+			}
+			languageSettingsDelta = new LanguageSettingsDelta(lspPersistedState, newStateDeep);
+			lspPersistedState = newStateDeep;
+		}
+		
+		return languageSettingsDelta;
+	}
+	
 }

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/pdom/LanguageSettingsChangeListener.java

@@ -0,0 +1,77 @@
+/*******************************************************************************
+ * Copyright (c) 2011, 2011 Andrew Gvozdev and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Andrew Gvozdev - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.cdt.internal.core.pdom;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.eclipse.cdt.core.CCorePlugin;
+import org.eclipse.cdt.core.index.IIndexManager;
+import org.eclipse.cdt.core.model.ICElement;
+import org.eclipse.cdt.core.model.ICProject;
+import org.eclipse.cdt.core.settings.model.ICConfigurationDescription;
+import org.eclipse.cdt.core.settings.model.ICProjectDescription;
+import org.eclipse.cdt.internal.core.language.settings.providers.ILanguageSettingsChangeEvent;
+import org.eclipse.cdt.internal.core.language.settings.providers.ILanguageSettingsChangeListener;
+import org.eclipse.cdt.internal.core.model.CModelManager;
+import org.eclipse.core.resources.IProject;
+import org.eclipse.core.resources.IResource;
+import org.eclipse.core.resources.IWorkspaceRoot;
+import org.eclipse.core.resources.ResourcesPlugin;
+import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.IStatus;
+import org.eclipse.core.runtime.Status;
+
+/**
+ *	This class handles changes in language settings for the PDOM by reindexing the appropriate resources.
+ */
+public class LanguageSettingsChangeListener implements ILanguageSettingsChangeListener {
+
+	private IIndexManager fManager;
+	
+	public LanguageSettingsChangeListener(IIndexManager manager) {
+		fManager = manager;
+	}
+	
+	public void handleEvent(ILanguageSettingsChangeEvent event) {
+		String projectName = event.getProjectName();
+		IWorkspaceRoot wspRoot = ResourcesPlugin.getWorkspace().getRoot();
+		IProject project = wspRoot.getProject(projectName);
+		
+		ICProjectDescription prjDescription = CCorePlugin.getDefault().getProjectDescription(project);
+		ICConfigurationDescription indexedCfgDescription = prjDescription.getDefaultSettingConfiguration();
+		
+		CModelManager manager = CModelManager.getDefault();
+
+		IResource[] resources = event.getResources(indexedCfgDescription.getId());
+		
+		if (resources.length > 0) {
+			ICProject cProject = manager.getCModel().getCProject(project);
+			List<ICElement> elements = new ArrayList<ICElement>();
+			
+			for (IResource rc : resources) {
+				// AG TODO - remove the log
+				CCorePlugin.log(new Status(IStatus.WARNING, CCorePlugin.PLUGIN_ID,
+						"LanguageSettingsChangeListener"+"["+System.identityHashCode(this)+"]"+".handleEvent() for " + rc, new Exception()));
+				
+				elements.add(manager.create(rc, cProject));
+			}
+			
+			try {
+				fManager.update(elements.toArray(new ICElement[elements.size()]), IIndexManager.UPDATE_ALL);
+			} catch (CoreException e) {
+				CCorePlugin.log(e);
+			}
+		}
+		
+	}
+
+}

core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/pdom/PDOMManager.java

@@ -60,6 +60,7 @@ import org.eclipse.cdt.core.model.ITranslationUnit;
 import org.eclipse.cdt.core.model.LanguageManager;
 import org.eclipse.cdt.core.settings.model.CProjectDescriptionEvent;
 import org.eclipse.cdt.core.settings.model.ICProjectDescriptionListener;
+import org.eclipse.cdt.core.settings.model.util.LanguageSettingEntriesSerializer;
 import org.eclipse.cdt.internal.core.CCoreInternals;
 import org.eclipse.cdt.internal.core.index.IIndexFragment;
 import org.eclipse.cdt.internal.core.index.IWritableIndex;
@@ -68,6 +69,7 @@ import org.eclipse.cdt.internal.core.index.IndexChangeEvent;
 import org.eclipse.cdt.internal.core.index.IndexFactory;
 import org.eclipse.cdt.internal.core.index.IndexerStateEvent;
 import org.eclipse.cdt.internal.core.index.provider.IndexProviderManager;
+import org.eclipse.cdt.internal.core.language.settings.providers.LanguageSettingsProvidersSerializer;
 import org.eclipse.cdt.internal.core.pdom.PDOM.IListener;
 import org.eclipse.cdt.internal.core.pdom.db.ChunkCache;
 import org.eclipse.cdt.internal.core.pdom.dom.IPDOMLinkageFactory;
@@ -163,6 +165,7 @@ public class PDOMManager implements IWritableIndexManager, IListener {
 
 	private CModelListener fCModelListener= new CModelListener(this);
 	private ILanguageMappingChangeListener fLanguageChangeListener = new LanguageMappingChangeListener(this);
+	private LanguageSettingsChangeListener fLanguageSettingsChangeListener = new LanguageSettingsChangeListener(this);
 	private final ICProjectDescriptionListener fProjectDescriptionListener;
 	private final JobChangeListener fJobChangeListener;
 	private final IPreferenceChangeListener fPreferenceChangeListener;
@@ -235,6 +238,7 @@ public class PDOMManager implements IWritableIndexManager, IListener {
 		ResourcesPlugin.getWorkspace().addResourceChangeListener(fCModelListener, IResourceChangeEvent.POST_BUILD);
 		model.addElementChangedListener(fCModelListener);
 		LanguageManager.getInstance().registerLanguageChangeListener(fLanguageChangeListener);
+		LanguageSettingsProvidersSerializer.registerLanguageSettingsChangeListener(fLanguageSettingsChangeListener);
 		final int types= CProjectDescriptionEvent.DATA_APPLIED;
 		CCorePlugin.getDefault().getProjectDescriptionManager().addCProjectDescriptionListener(fProjectDescriptionListener, types);
 
@@ -255,6 +259,7 @@ public class PDOMManager implements IWritableIndexManager, IListener {
 		final CoreModel model = CoreModel.getDefault();
 		model.removeElementChangedListener(fCModelListener);
 		ResourcesPlugin.getWorkspace().removeResourceChangeListener(fCModelListener);
+		LanguageSettingsProvidersSerializer.unregisterLanguageSettingsChangeListener(fLanguageSettingsChangeListener);
 		LanguageManager.getInstance().unregisterLanguageChangeListener(fLanguageChangeListener);
 		PDOMIndexerJob jobToCancel= null;
 		synchronized (fTaskQueue) {

core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/language/settings/providers/LanguageSettingsEntriesTab.java

@@ -21,7 +21,6 @@ import java.util.Map;
 
 import org.eclipse.core.resources.IProject;
 import org.eclipse.core.resources.IResource;
-import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.jface.viewers.IDecoration;
@@ -47,7 +46,6 @@ import org.eclipse.cdt.core.language.settings.providers.ILanguageSettingsEditabl
 import org.eclipse.cdt.core.language.settings.providers.ILanguageSettingsProvider;
 import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsBaseProvider;
 import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsManager;
-import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsManager_TBD;
 import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsSerializable;
 import org.eclipse.cdt.core.language.settings.providers.ScannerDiscoveryLegacySupport;
 import org.eclipse.cdt.core.model.ILanguage;
@@ -1020,14 +1018,6 @@ providers:	for (ILanguageSettingsProvider provider : providers) {
 			enableProvidersCheckBox.setSelection(enabled);
 		}
 
-		try {
-			LanguageSettingsManager_TBD.serializeWorkspaceProviders();
-		} catch (CoreException e) {
-			// TODO Auto-generated catch block
-			e.printStackTrace();
-			throw new UnsupportedOperationException("Internal Error");
-		}
-
 		trackInitialSettings();
 		updateData(getResDesc());
 	}
@@ -1063,19 +1053,4 @@ providers:	for (ILanguageSettingsProvider provider : providers) {
 			provider.setSettingEntries(cfgDescription, rc, currentLanguageId, entries);
 	}
 
-	@Override
-	protected boolean isIndexerAffected() {
-//		List<ILanguageSettingsProvider> newProvidersList = null;
-//		ICConfigurationDescription cfgDescription = getConfigurationDescription();
-//		if (cfgDescription!=null) {
-//			newProvidersList = cfgDescription.getLanguageSettingProviders();
-//		}
-//		boolean newEnablement = LanguageSettingsManager.isLanguageSettingsProvidersEnabled(page.getProject());
-//		
-//		boolean isEqualList = (newProvidersList==initialProvidersList) || (newProvidersList!=null && newProvidersList.equals(initialProvidersList));
-//		return newEnablement!=initialEnablement || (newEnablement==true && !isEqualList);
-		// FIXME
-		return true;
-	}
-
 }

core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/language/settings/providers/LanguageSettingsProviderTab.java

@@ -51,14 +51,8 @@ import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsManager;
 import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsManager_TBD;
 import org.eclipse.cdt.core.language.settings.providers.LanguageSettingsSerializable;
 import org.eclipse.cdt.core.language.settings.providers.ScannerDiscoveryLegacySupport;
-import org.eclipse.cdt.core.model.ILanguageDescriptor;
-import org.eclipse.cdt.core.model.LanguageManager;
 import org.eclipse.cdt.core.settings.model.ICConfigurationDescription;
-import org.eclipse.cdt.core.settings.model.ICFileDescription;
-import org.eclipse.cdt.core.settings.model.ICFolderDescription;
-import org.eclipse.cdt.core.settings.model.ICLanguageSetting;
 import org.eclipse.cdt.core.settings.model.ICResourceDescription;
-import org.eclipse.cdt.core.settings.model.ICSettingBase;
 import org.eclipse.cdt.ui.CDTSharedImages;
 import org.eclipse.cdt.ui.CUIPlugin;
 import org.eclipse.cdt.ui.dialogs.ICOptionPage;
@@ -66,7 +60,6 @@ import org.eclipse.cdt.ui.newui.AbstractCPropertyTab;
 import org.eclipse.cdt.ui.newui.CDTPrefUtil;
 import org.eclipse.cdt.utils.ui.controls.TabFolderLayout;
 
-
 import org.eclipse.cdt.internal.ui.newui.Messages;
 import org.eclipse.cdt.internal.ui.newui.StatusMessageLine;
 
@@ -983,13 +976,6 @@ public class LanguageSettingsProviderTab extends AbstractCPropertyTab {
 			}
 		}
 
-		try {
-			LanguageSettingsManager_TBD.serializeWorkspaceProviders();
-		} catch (CoreException e) {
-			CUIPlugin.log("Internal Error", e);
-			throw new UnsupportedOperationException("Internal Error");
-		}
-
 		trackInitialSettings();
 		updateData(getResDesc());
 	}
@@ -1002,21 +988,6 @@ public class LanguageSettingsProviderTab extends AbstractCPropertyTab {
 		return page.isForPrefs() || page.isForProject();
 	}
 
-	@Override
-	protected boolean isIndexerAffected() {
-		List<ILanguageSettingsProvider> newProvidersList = null;
-		ICConfigurationDescription cfgDescription = getConfigurationDescription();
-		if (cfgDescription!=null) {
-			newProvidersList = cfgDescription.getLanguageSettingProviders();
-		}
-		boolean newEnablement = ScannerDiscoveryLegacySupport.isLanguageSettingsProvidersFunctionalityEnabled(page.getProject());
-
-		// TODO
-		boolean isEqualList = false;
-//		boolean isEqualList = (newProvidersList==initialProvidersMap) || (newProvidersList!=null && newProvidersList.equals(initialProvidersMap));
-		return newEnablement!=initialEnablement || (newEnablement==true && !isEqualList);
-	}
-
 	private ILanguageSettingsProvider findRawProvider(String id, List<ILanguageSettingsProvider> providers) {
 		for (ILanguageSettingsProvider provider : providers) {
 			if (provider.getId().equals(id)) {