| /******************************************************************************* |
| * 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.x86; |
| |
| import java.math.BigInteger; |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| |
| import org.eclipse.cdt.debug.edc.MemoryUtils; |
| import org.eclipse.cdt.debug.edc.services.IEDCExecutionDMC; |
| import org.eclipse.cdt.debug.edc.services.IEDCMemory; |
| import org.eclipse.cdt.debug.edc.services.IEDCModuleDMContext; |
| import org.eclipse.cdt.debug.edc.services.IEDCModules; |
| import org.eclipse.cdt.debug.edc.services.Registers; |
| import org.eclipse.cdt.debug.edc.services.Stack; |
| import org.eclipse.cdt.dsf.service.DsfSession; |
| import org.eclipse.cdt.utils.Addr64; |
| import org.eclipse.core.runtime.CoreException; |
| import org.eclipse.core.runtime.IStatus; |
| import org.eclipse.debug.core.model.MemoryByte; |
| |
| public class X86Stack extends Stack { |
| |
| static class X86PreservedRegisters { |
| |
| // the values of registers stored in this frame |
| // note: only integer variables tracked |
| BigInteger registers[] = new BigInteger[8]; |
| |
| public Map<Integer, BigInteger> getPreservedRegisters() { |
| Map<Integer, BigInteger> map = new HashMap<Integer, BigInteger>(); |
| for (int i = 0; i < registers.length; i++) { |
| if (registers[i] != null) |
| map.put(i, registers[i]); |
| } |
| return map; |
| } |
| } |
| |
| public X86Stack(DsfSession session) { |
| super(session, new String[] { X86Stack.class.getName() }); |
| } |
| |
| /** |
| * Analyze the stack frame and try to decide what the base address (EBP or ESP), |
| * return address, and preserved registers are. |
| * |
| * If we are at the beginning of a function, the PUSH %EBP / MOV %ESP,%EBP |
| * instructions are a clue as to where the return address and previous base address have |
| * been placed. |
| * |
| * We may also have a jump into a DLL (a jmp *0xNNNN address) which is not yet a new |
| * stack frame. |
| * |
| * Otherwise, we assume that the current value of EBP is the base |
| * address. (TODO: optimized code might use EBP as a variable, so if it is far enough |
| * out of range of ESP, we must quit here.) |
| * @throws CoreException |
| * @throws NumberFormatException |
| */ |
| @Override |
| protected List<EdcStackFrame> computeStackFrames(IEDCExecutionDMC context, int startIndex, int endIndex) throws NumberFormatException, CoreException { |
| |
| ArrayList<EdcStackFrame> frames = new ArrayList<EdcStackFrame>(); |
| |
| IEDCModules modules = getService(IEDCModules.class); |
| IEDCMemory memoryService = getService(IEDCMemory.class); |
| Registers registersService = getService(Registers.class); |
| |
| |
| long eipValue = Long.valueOf(registersService.getRegisterValue(context, "EIP"), 16); |
| long espValue = Long.valueOf(registersService.getRegisterValue(context, "ESP"), 16); |
| long ebpValue = Long.valueOf(registersService.getRegisterValue(context, "EBP"), 16); |
| |
| long baseAddress = ebpValue; |
| long instructionAddress = eipValue; |
| long returnAddress = 0; |
| long previousBaseAddress = 0; |
| long previousPtrToBaseAddress = 0; |
| |
| while (true) { |
| int level = frames.size(); |
| |
| HashMap<String, Object> properties = new HashMap<String, Object>(); |
| |
| IEDCModuleDMContext module = modules.getModuleByAddress(context.getSymbolDMContext(), new Addr64(Long |
| .toString(instructionAddress))); |
| |
| boolean isFramePushed = true; |
| boolean detected = false; |
| X86PreservedRegisters preserved = new X86PreservedRegisters(); |
| |
| ArrayList<MemoryByte> memBuffer = new ArrayList<MemoryByte>(); |
| IStatus memGetStatus = memoryService.getMemory(context, new Addr64(Long.toString(eipValue)), memBuffer, 4, |
| 1); |
| |
| boolean validRead = memGetStatus.isOK(); |
| if (validRead) { |
| // check each byte |
| for (int i = 0; i < memBuffer.size(); i++) { |
| if (memBuffer.get(i) == null || !memBuffer.get(i).isReadable()) { |
| validRead = false; |
| break; |
| } |
| } |
| } |
| |
| if (validRead) { |
| byte op1 = memBuffer.get(0).getValue(); |
| byte op2 = memBuffer.size() > 1 ? memBuffer.get(1).getValue() : 0; |
| |
| if (level == 0) { |
| // the current instruction is special because it may be |
| // before the frame has been established |
| if (op1 == 0x55) { |
| // push %ebp -- only return address is on stack; base address is still %ebp |
| detected = true; |
| isFramePushed = false; |
| |
| previousBaseAddress = ebpValue; |
| returnAddress = readAddress(context, memoryService, espValue); |
| } |
| else if (op1 == (byte) 0x89 && op2 == (byte) 0xe5) { |
| // mov %esp, %ebp -- only return address and ebp are on stack; base address is still %ebp |
| detected = true; |
| isFramePushed = false; |
| |
| previousBaseAddress = ebpValue; |
| returnAddress = readAddress(context, memoryService, espValue + 4); |
| } |
| else if (op1 == (byte) 0xff && op2 == (byte) 0x25) { |
| // jmp *0xNNNNN -- likely we're in an __imp_xxx thunk, and the new frame is not pushed |
| detected = true; |
| isFramePushed = false; |
| |
| previousBaseAddress = ebpValue; |
| returnAddress = readAddress(context, memoryService, espValue); |
| } |
| } |
| if (!detected) { |
| // assume we're inside the function already |
| preserved.registers[X86Registers.EBP] = BigInteger.valueOf(level == 0 ? ebpValue : previousPtrToBaseAddress); |
| |
| previousPtrToBaseAddress = baseAddress; |
| previousBaseAddress = readAddress(context, memoryService, baseAddress); |
| returnAddress = readAddress(context, memoryService, baseAddress + 4); |
| } |
| } |
| |
| properties = new HashMap<String, Object>(); |
| properties.put(StackFrameDMC.LEVEL_INDEX, level); |
| properties.put(StackFrameDMC.BASE_ADDR, Long.valueOf(baseAddress)); |
| properties.put(StackFrameDMC.INSTRUCTION_PTR_ADDR, Long.valueOf(instructionAddress)); |
| if (module != null) properties.put(StackFrameDMC.MODULE_NAME, module.getName()); |
| if (level == 0) properties.put(StackFrameDMC.IN_PROLOGUE, !isFramePushed); |
| properties.put(StackFrameDMC.PRESERVED_REGISTERS, preserved.getPreservedRegisters()); |
| frames.add(new EdcStackFrame(properties)); |
| |
| // avoid recursive loop |
| if (level > 0 && baseAddress == previousBaseAddress) { |
| properties.put(StackFrameDMC.ROOT_FRAME, true); |
| break; |
| } |
| |
| baseAddress = previousBaseAddress; |
| instructionAddress = returnAddress; |
| |
| // Bail out when we hit the top of the stack frame |
| if (baseAddress == 0) { |
| properties.put(StackFrameDMC.ROOT_FRAME, true); |
| break; |
| } |
| } |
| |
| return frames; |
| } |
| |
| private long readAddress(IEDCExecutionDMC context, IEDCMemory memoryService, long addr) { |
| ArrayList<MemoryByte> memBuffer = new ArrayList<MemoryByte>(); |
| IStatus status = memoryService.getMemory(context, new Addr64(Long.toString(addr)), memBuffer, 4, 1); |
| if (!status.isOK()) |
| return 0; |
| |
| // check each byte |
| for (int i = 0; i < memBuffer.size(); i++) { |
| if (memBuffer.get(i) == null || !memBuffer.get(i).isReadable()) |
| return 0; |
| } |
| |
| return MemoryUtils.convertByteArrayToUnsignedLong( |
| memBuffer.subList(0, 4).toArray(new MemoryByte[4]), MemoryUtils.LITTLE_ENDIAN) |
| .longValue(); |
| } |
| |
| } |