Windbg源码调试

Windbg提供比VS2008丰富很多的调试命令，尤其是调试多线程程序。

今天试着怎么使用源代码方式调试。为了说明调试命令，《C++标准库》一书里的例子做示范。

// testcast.cpp

#include <stdio.h> 
#include <iostream>

struct A { 
    virtual void test() { 
        printf_s("in A
"); 
   } 
};

struct B : A { 
    virtual void test() { 
        printf_s("in B
"); 
    }

    void test2() { 
        printf_s("test2 in B
"); 
    } 
};

struct C : B { 
    virtual void test() { 
        printf_s("in C
"); 
    }

    void test2() { 
        printf_s("test2 in C
"); 
    } 
};

void Globaltest(A& a) { 
    try { 
        C &c = dynamic_cast<C&>(a); 
        printf_s("in GlobalTest
"); 
    } 
    catch(std::bad_cast) { 
        printf_s("Can't cast to C
"); 
    } 
}

int main() { 
    A *pa = new C; 
    A *pa2 = new B;

    pa->test();

    B * pb = dynamic_cast<B *>(pa); 
    if (pb) 
        pb->test2();

    C * pc = dynamic_cast<C *>(pa2); 
    if (pc) 
        pc->test2();

    C ConStack; 
    Globaltest(ConStack);

   // will fail because B knows nothing about C 
    B BonStack; 
    Globaltest(BonStack); 
} 

使用命令编译并连接 

cl.exe  testcast.cpp /Zi  
link  testcast.obj  /DEBUG

确保系统已经安装了windbg和symbol。
在命令行窗体，cd testcast.exe所在目录
Windbg  testcast.exe
打开Windbg窗体，进入到用户模式调试

命令行交互如下（蓝色为注释）：
Microsoft (R) Windows Debugger Version 6.2.9200.20512 AMD64
Copyright (c) Microsoft Corporation. All rights reserved.

CommandLine: testcast.exe
Symbol search path is: C:Symbols;d:CodeExerciseC++            
C:Symbols为Windows Symbols目录，使用.symfix  可以恢复sympath为微软网站上的symbol存储位置
.sympath     查看当前symbol目录
.sympath+  D:CodeExerciseC++         将“D:CodeExerciseC++ ”添加到symbol搜索路径中
.srcpath   查看源码搜索路径
.srcpath+  D:CodeExerciseC++           将“D:CodeExerciseC++ ” 添加到源码搜索路径中
Executable search path is:
ModLoad: 00000000`00ac0000 00000000`00af1000   testcast.exe
ModLoad: 00000000`77b40000 00000000`77cec000   ntdll.dll
ModLoad: 00000000`77d20000 00000000`77ea0000   ntdll32.dll
ModLoad: 00000000`73e80000 00000000`73ebf000   C:WindowsSYSTEM32wow64.dll
ModLoad: 00000000`73e20000 00000000`73e7c000   C:WindowsSYSTEM32wow64win.dll
ModLoad: 00000000`73e10000 00000000`73e18000   C:WindowsSYSTEM32wow64cpu.dll
(1a58.b40): Break instruction exception - code 80000003 (first chance)
*** ERROR: Symbol file could not be found.  Defaulted to export symbols for ntdll.dll -
ntdll!CsrSetPriorityClass+0x40:
00000000`77bf0fe0 cc              int     3
0:000> bl                  bl用于显示断点列表
0:000> bp  testcast!main          在testcast模块的main函数开头下断点
*** WARNING: Unable to verify checksum for testcast.exe
0:000> bp  testcast!Globaltest                      在testcast模块的Globaltest函数开头下断点
0:000> g                                  执行
ModLoad: 00000000`77920000 00000000`77a3f000   WOW64_IMAGE_SECTION
ModLoad: 00000000`75930000 00000000`75a40000   WOW64_IMAGE_SECTION
ModLoad: 00000000`77920000 00000000`77a3f000   NOT_AN_IMAGE
ModLoad: 00000000`77a40000 00000000`77b3a000   NOT_AN_IMAGE
ModLoad: 00000000`75930000 00000000`75a40000   C:Windowssyswow64kernel32.dll
ModLoad: 00000000`758e0000 00000000`75927000   C:Windowssyswow64KERNELBASE.dll
(1a58.b40): WOW64 breakpoint - code 4000001f (first chance)
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
*** ERROR: Symbol file could not be found.  Defaulted to export symbols for ntdll32.dll -
ntdll32!LdrVerifyImageMatchesChecksum+0x6ce:
77dc0e0b cc              int     3
0:000:x86> g
Breakpoint 0 hit
testcast!main:
00ac1100 55              push    ebp
0:000:x86> p             单步执行
testcast!main+0x6:
00ac1106 6a04            push    4
0:000:x86> t             单步跟踪
testcast!operator new:
00ac1fd9 8bff            mov     edi,edi
0:000:x86> t
testcast!operator new+0x2:
00ac1fdb 55              push    ebp
0:000:x86> t
testcast!operator new+0x3:
00ac1fdc 8bec            mov     ebp,esp
0:000:x86> p
testcast!operator new+0x5:
00ac1fde 83ec10          sub     esp,10h
0:000:x86> p
testcast!operator new+0x8:
00ac1fe1 eb0d            jmp     testcast!operator new+0x17 (00ac1ff0)
0:000:x86> p
testcast!operator new+0x17:
00ac1ff0 ff7508          push    dword ptr [ebp+8]    ss:002b:003bfd20=04000000
0:000:x86> p
testcast!operator new+0x1a:
00ac1ff3 e8293a0000      call    testcast!malloc (00ac5a21)
……
0:000:x86> p
testcast!Globaltest+0x4e:
00ac10be 68d84eae00      push    offset testcast!std::_Iosb<int>::end+0x4 (00ae4ed8)
0:000:x86> g
Breakpoint 1 hit
testcast!Globaltest:
00ac1070 55              push    ebp
0:000:x86> g
(1a58.b40): C++ EH exception - code e06d7363 (first chance)
*** ERROR: Symbol file could not be found.  Defaulted to export symbols for C:WindowsSYSTEM32wow64.dll -
ntdll!ZwTerminateProcess+0xa:                                             一直执行到进程退出
00000000`77b8f97a c3              ret
0:000> g
       ^ No runnable debuggees error in 'g'

调试过程截图