org.eclipse.cdt.debug.edc/src/org/eclipse/cdt/debug/edc/internal/services/dsf/Symbols.java - cdt/org.eclipse.cdt.edc - Git at Google

 /*******************************************************************************
  * Copyright (c) 2009, 2010 Nokia 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:
  * Nokia - Initial API and implementation
  *******************************************************************************/
 package org.eclipse.cdt.debug.edc.internal.services.dsf;

 import java.lang.ref.WeakReference;
 import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;

 import org.eclipse.cdt.core.IAddress;
 import org.eclipse.cdt.debug.edc.internal.EDCDebugger;
 import org.eclipse.cdt.debug.edc.internal.EDCTrace;
 import org.eclipse.cdt.debug.edc.internal.services.dsf.Modules.ModuleDMC;
 import org.eclipse.cdt.debug.edc.internal.symbols.ICompositeType;
 import org.eclipse.cdt.debug.edc.internal.symbols.files.DebugInfoProviderFactory;
 import org.eclipse.cdt.debug.edc.internal.symbols.files.ExecutableSymbolicsReaderFactory;
 import org.eclipse.cdt.debug.edc.internal.symbols.files.PEFileExecutableSymbolicsReader;
 import org.eclipse.cdt.debug.edc.services.AbstractEDCService;
 import org.eclipse.cdt.debug.edc.services.IEDCDMContext;
 import org.eclipse.cdt.debug.edc.services.IEDCExecutionDMC;
 import org.eclipse.cdt.debug.edc.services.IEDCModuleDMContext;
 import org.eclipse.cdt.debug.edc.services.IEDCModules;
 import org.eclipse.cdt.debug.edc.services.IEDCSymbols;
 import org.eclipse.cdt.debug.edc.services.IFrameRegisterProvider;
 import org.eclipse.cdt.debug.edc.services.IFrameRegisters;
 import org.eclipse.cdt.debug.edc.services.Stack.StackFrameDMC;
 import org.eclipse.cdt.debug.edc.symbols.IDebugInfoProvider;
 import org.eclipse.cdt.debug.edc.symbols.IEDCSymbolReader;
 import org.eclipse.cdt.debug.edc.symbols.IExecutableSymbolicsReader;
 import org.eclipse.cdt.debug.edc.symbols.IFunctionScope;
 import org.eclipse.cdt.debug.edc.symbols.ILineEntry;
 import org.eclipse.cdt.debug.edc.symbols.IModuleLineEntryProvider;
 import org.eclipse.cdt.debug.edc.symbols.IModuleScope;
 import org.eclipse.cdt.debug.edc.symbols.IScope;
 import org.eclipse.cdt.debug.edc.symbols.ISymbol;
 import org.eclipse.cdt.debug.edc.symbols.IType;
 import org.eclipse.cdt.dsf.concurrent.DataRequestMonitor;
 import org.eclipse.cdt.dsf.concurrent.RequestMonitor;
 import org.eclipse.cdt.dsf.datamodel.IDMContext;
 import org.eclipse.cdt.dsf.debug.service.IModules.IModuleDMContext;
 import org.eclipse.cdt.dsf.debug.service.IModules.ISymbolDMContext;
 import org.eclipse.cdt.dsf.debug.service.ISymbols;
 import org.eclipse.cdt.dsf.service.DsfSession;
 import org.eclipse.core.runtime.IPath;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.debug.core.model.ISourceLocator;

 public class Symbols extends AbstractEDCService implements ISymbols, IEDCSymbols {
 	private static Map<IPath, WeakReference<IEDCSymbolReader>> readerCache = new HashMap<IPath, WeakReference<IEDCSymbolReader>>();
 	private ISourceLocator sourceLocator;

 	public ISourceLocator getSourceLocator() {
 		return sourceLocator;
 	}

 	public void setSourceLocator(ISourceLocator sourceLocator) {
 		this.sourceLocator = sourceLocator;
 	}

 	public Symbols(DsfSession session) {
 		super(session, new String[] { IEDCSymbols.class.getName(), ISymbols.class.getName(), Symbols.class.getName() });
 	}

 	public void getSymbols(ISymbolDMContext symCtx, DataRequestMonitor<Iterable<ISymbolObjectDMContext>> rm) {
 		// TODO Auto-generated method stub

 	}

 	public void getModelData(IDMContext dmc, DataRequestMonitor<?> rm) {
 		// TODO Auto-generated method stub

 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.cdt.debug.edc.internal.services.dsf.IEDCSymbols#getFunctionAtAddress(org.eclipse.cdt.dsf.debug.service.IModules.ISymbolDMContext, org.eclipse.cdt.core.IAddress)
 	 */
 	public IFunctionScope getFunctionAtAddress(ISymbolDMContext context, IAddress runtimeAddress) {
 		IEDCModules modulesService = getService(Modules.class);
 		IEDCModuleDMContext module = modulesService.getModuleByAddress(context, runtimeAddress);
 		if (module != null) {
 			IEDCSymbolReader reader = module.getSymbolReader();
 			if (reader != null) {
 				IScope scope = reader.getModuleScope().getScopeAtAddress(module.toLinkAddress(runtimeAddress));
 				while (scope != null && !(scope instanceof IFunctionScope)) {
 					scope = scope.getParent();
 				}
 				return (IFunctionScope) scope;
 			}
 		}
 		return null;
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.cdt.debug.edc.internal.services.dsf.IEDCSymbols#getFunctionAtAddress(org.eclipse.cdt.dsf.debug.service.IModules.ISymbolDMContext, org.eclipse.cdt.core.IAddress)
 	 */
 	public String getSymbolNameAtAddress(ISymbolDMContext context, IAddress runtimeAddress) {
 		IEDCModules modulesService = getService(Modules.class);
 		IEDCModuleDMContext module = modulesService.getModuleByAddress(context, runtimeAddress);
 		if (module != null) {
 			IEDCSymbolReader reader = module.getSymbolReader();
 			if (reader != null) {
 				ISymbol symbol = reader.getSymbolAtAddress(module.toLinkAddress(runtimeAddress));
 				if (symbol != null)
 					return symbol.getName();
 			}
 		}
 		return null;
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.cdt.debug.edc.internal.services.dsf.IEDCSymbols#getLineEntryForAddress(org.eclipse.cdt.dsf.debug.service.IModules.ISymbolDMContext, org.eclipse.cdt.core.IAddress)
 	 */
 	public ILineEntry getLineEntryForAddress(ISymbolDMContext context, IAddress runtimeAddress) {
 		IEDCModules modulesService = getService(Modules.class);
 		IEDCModuleDMContext module = modulesService.getModuleByAddress(context, runtimeAddress);
 		if (module != null) {
 			IEDCSymbolReader reader = module.getSymbolReader();
 			if (reader != null) {
 				IAddress linkAddress = module.toLinkAddress(runtimeAddress);
 				IModuleLineEntryProvider lineEntryProvider = reader.getModuleScope().getModuleLineEntryProvider();
 				return lineEntryProvider.getLineEntryAtAddress(linkAddress);
 			}
 		}
 		return null;
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.cdt.debug.edc.internal.services.dsf.IEDCSymbols#getLineEntriesForAddressRange(org.eclipse.cdt.dsf.debug.service.IModules.ISymbolDMContext, org.eclipse.cdt.core.IAddress, org.eclipse.cdt.core.IAddress)
 	 */
 	public List<ILineEntry> getLineEntriesForAddressRange(ISymbolDMContext context, IAddress start, IAddress end) {
 		List<ILineEntry> lineEntries = new ArrayList<ILineEntry>();

 		IEDCModules modulesService = getService(Modules.class);
 		IEDCModuleDMContext module = modulesService.getModuleByAddress(context, start);
 		if (module == null)
 			return lineEntries;

 		IAddress linkStartAddress = module.toLinkAddress(start);
 		IAddress linkEndAddress = module.toLinkAddress(end);

 		IEDCSymbolReader reader = module.getSymbolReader();
 		if (reader != null) {
 			if (linkStartAddress == null)
 				linkStartAddress = module.getSymbolReader().getModuleScope().getLowAddress();
 			if (linkEndAddress == null)
 				linkEndAddress = module.getSymbolReader().getModuleScope().getHighAddress();

 			IModuleScope moduleScope = reader.getModuleScope();

 			if (linkEndAddress.compareTo(moduleScope.getHighAddress()) > 0) {
 				// end address is out of the module sections.
 				// we'll keep getting source lines until we reach an address
 				// point where no source line is available.
 				linkEndAddress = moduleScope.getHighAddress();
 			}

 			IModuleLineEntryProvider lineEntryProvider = moduleScope.getModuleLineEntryProvider();

 			ILineEntry entry = lineEntryProvider.getLineEntryAtAddress(linkStartAddress);
 			while (entry != null && entry.getLowAddress().compareTo(linkEndAddress) < 0) {
 				lineEntries.add(entry);
 				// FIXME: this shouldn't happen
 				if (entry.getLowAddress().compareTo(entry.getHighAddress()) >= 0)
 					entry = lineEntryProvider.getLineEntryAtAddress(entry.getHighAddress().add(1));
 				else
 					entry = lineEntryProvider.getLineEntryAtAddress(entry.getHighAddress());
 			}
 		}

 		return lineEntries;
 	}

 	/**
 	 * Get an accessor for registers in stack frames other than the current one.
 	 * <p>
 	 * Note: this is not meaningful by itselfis typically used from {@link StackFrameDMC#getFrameRegisters()}.
 	 * @param context
 	 * @param runtimeAddress
 	 * @return {@link IFrameRegisters} or <code>null</code>
 	 */
 	public IFrameRegisterProvider getFrameRegisterProvider(ISymbolDMContext context, IAddress runtimeAddress) {
 		Modules modulesService = getService(Modules.class);
 		IEDCModuleDMContext module = modulesService.getModuleByAddress(context, runtimeAddress);
 		if (module != null) {
 			IEDCSymbolReader reader = module.getSymbolReader();
 			if (reader != null) {
 				IFrameRegisterProvider frameRegisterProvider = reader.getModuleScope().getFrameRegisterProvider();
 				return frameRegisterProvider;
 			}
 		}
 		return null;
 	}

 	public static IEDCSymbolReader getSymbolReader(IPath modulePath) {

 		IEDCSymbolReader reader = null;
 		WeakReference<IEDCSymbolReader> cacheEntry = readerCache.get(modulePath);

 		if (cacheEntry != null)
 			reader = cacheEntry.get();

 		if (reader != null) {
 			if (reader.getSymbolFile() != null
 					&& reader.getSymbolFile().toFile().exists()
 					&& reader.getSymbolFile().toFile().lastModified() == reader.getModificationDate()) {
 				return reader;
 			}

 			// it's been deleted or modified. remove it from the cache
 			readerCache.remove(modulePath);
 		}

 		IExecutableSymbolicsReader exeReader = ExecutableSymbolicsReaderFactory.createFor(modulePath);
 		if (exeReader != null) {
 			IDebugInfoProvider debugProvider = DebugInfoProviderFactory.createFor(modulePath, exeReader); // may be null
 			if (debugProvider != null) {
 				// if debug info came from a different file, the "executable" may be that symbol file too
 				if (!exeReader.getSymbolFile().equals(debugProvider.getExecutableSymbolicsReader().getSymbolFile())) {
 					exeReader.dispose();
 					exeReader = debugProvider.getExecutableSymbolicsReader();
 				}
 			}
 			reader = new EDCSymbolReader(exeReader, debugProvider);
 		}

 		if (reader != null) {
 			readerCache.put(modulePath, new WeakReference<IEDCSymbolReader>(reader));
 		}

 		return reader;
 	}

 	@Override
 	public void shutdown(RequestMonitor rm) {
 		super.shutdown(rm);
 	}

 	/**
 	 * This is exposed only for testing.
 	 */
 	public static void releaseReaderCache() {
 		Collection<WeakReference<IEDCSymbolReader>> readers = readerCache.values();
 		for (WeakReference<IEDCSymbolReader> readerRef : readers) {
 			IEDCSymbolReader reader = readerRef.get();
 			if (reader != null)
 				reader.shutDown();
 		}
 		readerCache.clear();
 	}

 	/**
 	 * Given an opaque composite type, search the symbol context for definition
 	 * of the type.
 	 *
 	 * A C/C++ opaque type is usually used in opaque pointer, e.g.
 	 *
 	 * <pre>
 	 * typedef class PrivateType* OpaquePTR;
 	 * </pre>
 	 *
 	 * The actual definition of the "PrivateType" is usually in another
 	 * library/DLL with or without debug info.<br>
 	 * <br>
 	 * This method will search all modules loaded in the symbol context (usually
 	 * a process) until it finds a non-opaque type with the same name as the
 	 * given opaque type. If a loaded module has no debug info, it will just be
 	 * skipped.
 	 *
 	 * @param symCtx
 	 *            the symbol context (usually a process)
 	 * @param type
 	 *            the opaque composite type
 	 * @return a defined type; null if no defined type is found or the given
 	 *         type is not opaque.
 	 */
 	public ICompositeType resolveOpaqueType(ISymbolDMContext symCtx, ICompositeType type) {
 		ICompositeType result = null;
 		if (type == null || ! type.isOpaque()) {
 			return result;
 		}

 		if (EDCTrace.SYMBOL_READER_TRACE_ON) {
 			EDCTrace.getTrace().traceEntry(null, "Resolve opaque type \"" + type.getName() + "\" in " + EDCTrace.fixArg(symCtx));
 		}

 		IModuleDMContext[] moduleList = null;

 		Modules modulesService = getService(Modules.class);
 		assert(modulesService != null);

 		if (symCtx instanceof IEDCExecutionDMC) {
 			String symContextID = ((IEDCDMContext) symCtx).getID();
 			moduleList = modulesService.getModulesForContext(symContextID);
 		} else if (symCtx instanceof IModuleDMContext) {
 			moduleList = new IModuleDMContext[1];
 			moduleList[0] = (IModuleDMContext) symCtx;
 		} else {
 			// should not happen
 			Status s = new Status(IStatus.ERROR, EDCDebugger.PLUGIN_ID, REQUEST_FAILED, MessageFormat.format(
 					"Unknown class implementing ISymbolDMContext : {0}", symCtx.getClass().getName()), null);

 			if (EDCTrace.SYMBOL_READER_TRACE_ON)
 				EDCTrace.getTrace().traceExit(null,	s);
 			return result;
 		}

 		for (IModuleDMContext module : moduleList) {
 			ModuleDMC mdmc = (ModuleDMC) module;
 			EDCSymbolReader reader = (EDCSymbolReader)mdmc.getSymbolReader();

 			if (reader == null || reader.getDebugInfoProvider() == null) // no debug info
 				continue;

 			Collection<IType> types = reader.getDebugInfoProvider().getTypesByName(type.getName());
 			if (types == null)
 				return result;

 			for (IType t : types) {
 				if (t instanceof ICompositeType && ! ((ICompositeType)t).isOpaque()) {
 					result = (ICompositeType)t;
 					break;
 				}
 			}

 		}

 		return result;
 	}

 	/**
 	 * A wrapper method that calls into symbol reader to get runtime address(es)
 	 * for a given function name.
 	 * For executables that are not PE-COFF, this method only uses the symbol table instead of
 	 * also debug info (e.g. Dwarf3) to get function address. See reason in the implementation.
 	 *
 	 * @param module where the runtime address is.
 	 * @param functionName
 	 * @return list of runtime addresses.
 	 */
 	public List<IAddress> getFunctionAddress(IEDCModuleDMContext module, String functionName) {

 		List<IAddress> ret = new ArrayList<IAddress>(2);

 		IEDCSymbolReader symReader = module.getSymbolReader();
 		if (symReader == null)
 			return ret;

 		// Remove "()" if any
 		int parenIndex = functionName.indexOf('(');
 		if (parenIndex >= 0)
 			functionName = functionName.substring(0, parenIndex);

 		// Supposedly we could call this to get what we need, but this may cause full parse of
 		// debug info and lead to heap overflow for a large symbol file (over one gigabytes of
 		// memory required in parsing a 180M ELF symbol file) and chokes the debugger.
 		// So before a good solution is available, we resort to symbol table of the executable.
 		// ................04/02/10
 //			Collection<IFunctionScope> functions = symReader.getModuleScope().getFunctionsByName(functionName);
 //			for (IFunctionScope f : functions) {
 //				IAddress breakAddr = f.getLowAddress();
 //		        ...

 		// assume it's the human-readable name first
 		Collection<ISymbol> symbols = symReader.findUnmangledSymbols(functionName);
 		if (symbols.isEmpty()) {
 			// else look for a raw symbol
 			symbols = symReader.findSymbols(functionName);
 		}

 		if (symbols.isEmpty() && symReader.getSymbolicsReader() instanceof PEFileExecutableSymbolicsReader) {
 			// for PE-COFF files, if the name is not in the symbol list, search the debug info
 			IFunctionScope function = symReader.getModuleScope().getFunctionByName(functionName);
 			if (function != null)
 				ret.add(function.getLowAddress());
 		} else for (ISymbol symbol : symbols) {
 			// don't consider zero sized symbol.
 			if (symbol.getSize() ==  0)
 				continue;

 			IAddress addr = symbol.getAddress();
 			// convert from link to runtime address
 			addr = module.toRuntimeAddress(addr);

 			ret.add(addr);
 		}

 		return ret;
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2009, 2010 Nokia 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:
	* Nokia - Initial API and implementation
	*******************************************************************************/
	package org.eclipse.cdt.debug.edc.internal.services.dsf;

	import java.lang.ref.WeakReference;
	import java.text.MessageFormat;
	import java.util.ArrayList;
	import java.util.Collection;
	import java.util.HashMap;
	import java.util.List;
	import java.util.Map;

	import org.eclipse.cdt.core.IAddress;
	import org.eclipse.cdt.debug.edc.internal.EDCDebugger;
	import org.eclipse.cdt.debug.edc.internal.EDCTrace;
	import org.eclipse.cdt.debug.edc.internal.services.dsf.Modules.ModuleDMC;
	import org.eclipse.cdt.debug.edc.internal.symbols.ICompositeType;
	import org.eclipse.cdt.debug.edc.internal.symbols.files.DebugInfoProviderFactory;
	import org.eclipse.cdt.debug.edc.internal.symbols.files.ExecutableSymbolicsReaderFactory;
	import org.eclipse.cdt.debug.edc.internal.symbols.files.PEFileExecutableSymbolicsReader;
	import org.eclipse.cdt.debug.edc.services.AbstractEDCService;
	import org.eclipse.cdt.debug.edc.services.IEDCDMContext;
	import org.eclipse.cdt.debug.edc.services.IEDCExecutionDMC;
	import org.eclipse.cdt.debug.edc.services.IEDCModuleDMContext;
	import org.eclipse.cdt.debug.edc.services.IEDCModules;
	import org.eclipse.cdt.debug.edc.services.IEDCSymbols;
	import org.eclipse.cdt.debug.edc.services.IFrameRegisterProvider;
	import org.eclipse.cdt.debug.edc.services.IFrameRegisters;
	import org.eclipse.cdt.debug.edc.services.Stack.StackFrameDMC;
	import org.eclipse.cdt.debug.edc.symbols.IDebugInfoProvider;
	import org.eclipse.cdt.debug.edc.symbols.IEDCSymbolReader;
	import org.eclipse.cdt.debug.edc.symbols.IExecutableSymbolicsReader;
	import org.eclipse.cdt.debug.edc.symbols.IFunctionScope;
	import org.eclipse.cdt.debug.edc.symbols.ILineEntry;
	import org.eclipse.cdt.debug.edc.symbols.IModuleLineEntryProvider;
	import org.eclipse.cdt.debug.edc.symbols.IModuleScope;
	import org.eclipse.cdt.debug.edc.symbols.IScope;
	import org.eclipse.cdt.debug.edc.symbols.ISymbol;
	import org.eclipse.cdt.debug.edc.symbols.IType;
	import org.eclipse.cdt.dsf.concurrent.DataRequestMonitor;
	import org.eclipse.cdt.dsf.concurrent.RequestMonitor;
	import org.eclipse.cdt.dsf.datamodel.IDMContext;
	import org.eclipse.cdt.dsf.debug.service.IModules.IModuleDMContext;
	import org.eclipse.cdt.dsf.debug.service.IModules.ISymbolDMContext;
	import org.eclipse.cdt.dsf.debug.service.ISymbols;
	import org.eclipse.cdt.dsf.service.DsfSession;
	import org.eclipse.core.runtime.IPath;
	import org.eclipse.core.runtime.IStatus;
	import org.eclipse.core.runtime.Status;
	import org.eclipse.debug.core.model.ISourceLocator;

	public class Symbols extends AbstractEDCService implements ISymbols, IEDCSymbols {
	private static Map<IPath, WeakReference<IEDCSymbolReader>> readerCache = new HashMap<IPath, WeakReference<IEDCSymbolReader>>();
	private ISourceLocator sourceLocator;

	public ISourceLocator getSourceLocator() {
	return sourceLocator;
	}

	public void setSourceLocator(ISourceLocator sourceLocator) {
	this.sourceLocator = sourceLocator;
	}

	public Symbols(DsfSession session) {
	super(session, new String[] { IEDCSymbols.class.getName(), ISymbols.class.getName(), Symbols.class.getName() });
	}

	public void getSymbols(ISymbolDMContext symCtx, DataRequestMonitor<Iterable<ISymbolObjectDMContext>> rm) {
	// TODO Auto-generated method stub

	}

	public void getModelData(IDMContext dmc, DataRequestMonitor<?> rm) {
	// TODO Auto-generated method stub

	}

	/* (non-Javadoc)
	* @see org.eclipse.cdt.debug.edc.internal.services.dsf.IEDCSymbols#getFunctionAtAddress(org.eclipse.cdt.dsf.debug.service.IModules.ISymbolDMContext, org.eclipse.cdt.core.IAddress)
	*/
	public IFunctionScope getFunctionAtAddress(ISymbolDMContext context, IAddress runtimeAddress) {
	IEDCModules modulesService = getService(Modules.class);
	IEDCModuleDMContext module = modulesService.getModuleByAddress(context, runtimeAddress);
	if (module != null) {
	IEDCSymbolReader reader = module.getSymbolReader();
	if (reader != null) {
	IScope scope = reader.getModuleScope().getScopeAtAddress(module.toLinkAddress(runtimeAddress));
	while (scope != null && !(scope instanceof IFunctionScope)) {
	scope = scope.getParent();
	}
	return (IFunctionScope) scope;
	}
	}
	return null;
	}

	/* (non-Javadoc)
	* @see org.eclipse.cdt.debug.edc.internal.services.dsf.IEDCSymbols#getFunctionAtAddress(org.eclipse.cdt.dsf.debug.service.IModules.ISymbolDMContext, org.eclipse.cdt.core.IAddress)
	*/
	public String getSymbolNameAtAddress(ISymbolDMContext context, IAddress runtimeAddress) {
	IEDCModules modulesService = getService(Modules.class);
	IEDCModuleDMContext module = modulesService.getModuleByAddress(context, runtimeAddress);
	if (module != null) {
	IEDCSymbolReader reader = module.getSymbolReader();
	if (reader != null) {
	ISymbol symbol = reader.getSymbolAtAddress(module.toLinkAddress(runtimeAddress));
	if (symbol != null)
	return symbol.getName();
	}
	}
	return null;
	}

	/* (non-Javadoc)
	* @see org.eclipse.cdt.debug.edc.internal.services.dsf.IEDCSymbols#getLineEntryForAddress(org.eclipse.cdt.dsf.debug.service.IModules.ISymbolDMContext, org.eclipse.cdt.core.IAddress)
	*/
	public ILineEntry getLineEntryForAddress(ISymbolDMContext context, IAddress runtimeAddress) {
	IEDCModules modulesService = getService(Modules.class);
	IEDCModuleDMContext module = modulesService.getModuleByAddress(context, runtimeAddress);
	if (module != null) {
	IEDCSymbolReader reader = module.getSymbolReader();
	if (reader != null) {
	IAddress linkAddress = module.toLinkAddress(runtimeAddress);
	IModuleLineEntryProvider lineEntryProvider = reader.getModuleScope().getModuleLineEntryProvider();
	return lineEntryProvider.getLineEntryAtAddress(linkAddress);
	}
	}
	return null;
	}

	/* (non-Javadoc)
	* @see org.eclipse.cdt.debug.edc.internal.services.dsf.IEDCSymbols#getLineEntriesForAddressRange(org.eclipse.cdt.dsf.debug.service.IModules.ISymbolDMContext, org.eclipse.cdt.core.IAddress, org.eclipse.cdt.core.IAddress)
	*/
	public List<ILineEntry> getLineEntriesForAddressRange(ISymbolDMContext context, IAddress start, IAddress end) {
	List<ILineEntry> lineEntries = new ArrayList<ILineEntry>();

	IEDCModules modulesService = getService(Modules.class);
	IEDCModuleDMContext module = modulesService.getModuleByAddress(context, start);
	if (module == null)
	return lineEntries;

	IAddress linkStartAddress = module.toLinkAddress(start);
	IAddress linkEndAddress = module.toLinkAddress(end);

	IEDCSymbolReader reader = module.getSymbolReader();
	if (reader != null) {
	if (linkStartAddress == null)
	linkStartAddress = module.getSymbolReader().getModuleScope().getLowAddress();
	if (linkEndAddress == null)
	linkEndAddress = module.getSymbolReader().getModuleScope().getHighAddress();

	IModuleScope moduleScope = reader.getModuleScope();

	if (linkEndAddress.compareTo(moduleScope.getHighAddress()) > 0) {
	// end address is out of the module sections.
	// we'll keep getting source lines until we reach an address
	// point where no source line is available.
	linkEndAddress = moduleScope.getHighAddress();
	}

	IModuleLineEntryProvider lineEntryProvider = moduleScope.getModuleLineEntryProvider();

	ILineEntry entry = lineEntryProvider.getLineEntryAtAddress(linkStartAddress);
	while (entry != null && entry.getLowAddress().compareTo(linkEndAddress) < 0) {
	lineEntries.add(entry);
	// FIXME: this shouldn't happen
	if (entry.getLowAddress().compareTo(entry.getHighAddress()) >= 0)
	entry = lineEntryProvider.getLineEntryAtAddress(entry.getHighAddress().add(1));
	else
	entry = lineEntryProvider.getLineEntryAtAddress(entry.getHighAddress());
	}
	}

	return lineEntries;
	}

	/**
	* Get an accessor for registers in stack frames other than the current one.
	* <p>
	* Note: this is not meaningful by itselfis typically used from {@link StackFrameDMC#getFrameRegisters()}.
	* @param context
	* @param runtimeAddress
	* @return {@link IFrameRegisters} or <code>null</code>
	*/
	public IFrameRegisterProvider getFrameRegisterProvider(ISymbolDMContext context, IAddress runtimeAddress) {
	Modules modulesService = getService(Modules.class);
	IEDCModuleDMContext module = modulesService.getModuleByAddress(context, runtimeAddress);
	if (module != null) {
	IEDCSymbolReader reader = module.getSymbolReader();
	if (reader != null) {
	IFrameRegisterProvider frameRegisterProvider = reader.getModuleScope().getFrameRegisterProvider();
	return frameRegisterProvider;
	}
	}
	return null;
	}

	public static IEDCSymbolReader getSymbolReader(IPath modulePath) {

	IEDCSymbolReader reader = null;
	WeakReference<IEDCSymbolReader> cacheEntry = readerCache.get(modulePath);

	if (cacheEntry != null)
	reader = cacheEntry.get();

	if (reader != null) {
	if (reader.getSymbolFile() != null
	&& reader.getSymbolFile().toFile().exists()
	&& reader.getSymbolFile().toFile().lastModified() == reader.getModificationDate()) {
	return reader;
	}

	// it's been deleted or modified. remove it from the cache
	readerCache.remove(modulePath);
	}

	IExecutableSymbolicsReader exeReader = ExecutableSymbolicsReaderFactory.createFor(modulePath);
	if (exeReader != null) {
	IDebugInfoProvider debugProvider = DebugInfoProviderFactory.createFor(modulePath, exeReader); // may be null
	if (debugProvider != null) {
	// if debug info came from a different file, the "executable" may be that symbol file too
	if (!exeReader.getSymbolFile().equals(debugProvider.getExecutableSymbolicsReader().getSymbolFile())) {
	exeReader.dispose();
	exeReader = debugProvider.getExecutableSymbolicsReader();
	}
	}
	reader = new EDCSymbolReader(exeReader, debugProvider);
	}

	if (reader != null) {
	readerCache.put(modulePath, new WeakReference<IEDCSymbolReader>(reader));
	}

	return reader;
	}

	@Override
	public void shutdown(RequestMonitor rm) {
	super.shutdown(rm);
	}

	/**
	* This is exposed only for testing.
	*/
	public static void releaseReaderCache() {
	Collection<WeakReference<IEDCSymbolReader>> readers = readerCache.values();
	for (WeakReference<IEDCSymbolReader> readerRef : readers) {
	IEDCSymbolReader reader = readerRef.get();
	if (reader != null)
	reader.shutDown();
	}
	readerCache.clear();
	}

	/**
	* Given an opaque composite type, search the symbol context for definition
	* of the type.
	*
	* A C/C++ opaque type is usually used in opaque pointer, e.g.
	*
	* <pre>
	* typedef class PrivateType* OpaquePTR;
	* </pre>
	*
	* The actual definition of the "PrivateType" is usually in another
	* library/DLL with or without debug info.<br>
	* <br>
	* This method will search all modules loaded in the symbol context (usually
	* a process) until it finds a non-opaque type with the same name as the
	* given opaque type. If a loaded module has no debug info, it will just be
	* skipped.
	*
	* @param symCtx
	* the symbol context (usually a process)
	* @param type
	* the opaque composite type
	* @return a defined type; null if no defined type is found or the given
	* type is not opaque.
	*/
	public ICompositeType resolveOpaqueType(ISymbolDMContext symCtx, ICompositeType type) {
	ICompositeType result = null;
	if (type == null \|\| ! type.isOpaque()) {
	return result;
	}

	if (EDCTrace.SYMBOL_READER_TRACE_ON) {
	EDCTrace.getTrace().traceEntry(null, "Resolve opaque type \"" + type.getName() + "\" in " + EDCTrace.fixArg(symCtx));
	}

	IModuleDMContext[] moduleList = null;

	Modules modulesService = getService(Modules.class);
	assert(modulesService != null);

	if (symCtx instanceof IEDCExecutionDMC) {
	String symContextID = ((IEDCDMContext) symCtx).getID();
	moduleList = modulesService.getModulesForContext(symContextID);
	} else if (symCtx instanceof IModuleDMContext) {
	moduleList = new IModuleDMContext[1];
	moduleList[0] = (IModuleDMContext) symCtx;
	} else {
	// should not happen
	Status s = new Status(IStatus.ERROR, EDCDebugger.PLUGIN_ID, REQUEST_FAILED, MessageFormat.format(
	"Unknown class implementing ISymbolDMContext : {0}", symCtx.getClass().getName()), null);

	if (EDCTrace.SYMBOL_READER_TRACE_ON)
	EDCTrace.getTrace().traceExit(null, s);
	return result;
	}

	for (IModuleDMContext module : moduleList) {
	ModuleDMC mdmc = (ModuleDMC) module;
	EDCSymbolReader reader = (EDCSymbolReader)mdmc.getSymbolReader();

	if (reader == null \|\| reader.getDebugInfoProvider() == null) // no debug info
	continue;

	Collection<IType> types = reader.getDebugInfoProvider().getTypesByName(type.getName());
	if (types == null)
	return result;

	for (IType t : types) {
	if (t instanceof ICompositeType && ! ((ICompositeType)t).isOpaque()) {
	result = (ICompositeType)t;
	break;
	}
	}

	}

	return result;
	}

	/**
	* A wrapper method that calls into symbol reader to get runtime address(es)
	* for a given function name.
	* For executables that are not PE-COFF, this method only uses the symbol table instead of
	* also debug info (e.g. Dwarf3) to get function address. See reason in the implementation.
	*
	* @param module where the runtime address is.
	* @param functionName
	* @return list of runtime addresses.
	*/
	public List<IAddress> getFunctionAddress(IEDCModuleDMContext module, String functionName) {

	List<IAddress> ret = new ArrayList<IAddress>(2);

	IEDCSymbolReader symReader = module.getSymbolReader();
	if (symReader == null)
	return ret;

	// Remove "()" if any
	int parenIndex = functionName.indexOf('(');
	if (parenIndex >= 0)
	functionName = functionName.substring(0, parenIndex);

	// Supposedly we could call this to get what we need, but this may cause full parse of
	// debug info and lead to heap overflow for a large symbol file (over one gigabytes of
	// memory required in parsing a 180M ELF symbol file) and chokes the debugger.
	// So before a good solution is available, we resort to symbol table of the executable.
	// ................04/02/10
	// Collection<IFunctionScope> functions = symReader.getModuleScope().getFunctionsByName(functionName);
	// for (IFunctionScope f : functions) {
	// IAddress breakAddr = f.getLowAddress();
	// ...

	// assume it's the human-readable name first
	Collection<ISymbol> symbols = symReader.findUnmangledSymbols(functionName);
	if (symbols.isEmpty()) {
	// else look for a raw symbol
	symbols = symReader.findSymbols(functionName);
	}

	if (symbols.isEmpty() && symReader.getSymbolicsReader() instanceof PEFileExecutableSymbolicsReader) {
	// for PE-COFF files, if the name is not in the symbol list, search the debug info
	IFunctionScope function = symReader.getModuleScope().getFunctionByName(functionName);
	if (function != null)
	ret.add(function.getLowAddress());
	} else for (ISymbol symbol : symbols) {
	// don't consider zero sized symbol.
	if (symbol.getSize() == 0)
	continue;

	IAddress addr = symbol.getAddress();
	// convert from link to runtime address
	addr = module.toRuntimeAddress(addr);

	ret.add(addr);
	}

	return ret;
	}

	}