stackwalker.cpp

Extended C/C++ Dynamic Memory Control And Debug Library

          szSymType = "Virtual";
          break;
#if API_VERSION_NUMBER >= 9
        case SymDia:
          szSymType = "DIA";
          break;
#endif
        }
      }
      this->m_parent->OnLoadModule(img, mod, baseAddr, size, result, szSymType, Module.LoadedImageName, fileVersion);
    }
    if (szImg != NULL) 
      free(szImg);
    if (szMod != NULL) 
      free(szMod);
    return result;
  }
public:
  BOOL LoadModules(HANDLE hProcess, DWORD dwProcessId)
  {
    // first try toolhelp32
    if (GetModuleListTH32(hProcess, dwProcessId))
      return true;
    // then try psapi
    return GetModuleListPSAPI(hProcess);
  }

  char m_Data[4096];    // @@@@ XMEM: reserve space with class member, do not allocate dynamically (performance reason)

  BOOL GetModuleInfo(HANDLE hProcess, DWORD64 baseAddr, IMAGEHLP_MODULE64_V2 *pModuleInfo)
  {
    if(this->pSGMI == NULL)
    {
      SetLastError(ERROR_DLL_INIT_FAILED);
      return FALSE;
    }
    // First try to use the larger ModuleInfo-Structure
//    memset(pModuleInfo, 0, sizeof(IMAGEHLP_MODULE64_V3));
//    pModuleInfo->SizeOfStruct = sizeof(IMAGEHLP_MODULE64_V3);
//    if (this->pSGMI_V3 != NULL)
//    {
//      if (this->pSGMI_V3(hProcess, baseAddr, pModuleInfo) != FALSE)
//        return TRUE;
//      // check if the parameter was wrong (size is bad...)
//      if (GetLastError() != ERROR_INVALID_PARAMETER)
//        return FALSE;
//    }
    // could not retrive the bigger structure, try with the smaller one (as defined in VC7.1)...
    pModuleInfo->SizeOfStruct = sizeof(IMAGEHLP_MODULE64_V2);
// /*@@@@ XMEM*/   void *pData = malloc(4096); // reserve enough memory, so the bug in v6.3.5.1 does not lead to memory-overwrites...
// /*@@@@ XMEM*/   if (pData == NULL)
// /*@@@@ XMEM*/   {
// /*@@@@ XMEM*/     SetLastError(ERROR_NOT_ENOUGH_MEMORY);
// /*@@@@ XMEM*/     return FALSE;
// /*@@@@ XMEM*/   }
    memcpy(m_Data, pModuleInfo, sizeof(IMAGEHLP_MODULE64_V2));      // @@@@ XMEM
    if (this->pSGMI != NULL)
    {
      if (this->pSGMI(hProcess, baseAddr, (IMAGEHLP_MODULE64_V2*) m_Data)) 
      {
        // only copy as much memory as is reserved...
        memcpy(pModuleInfo, m_Data, sizeof(IMAGEHLP_MODULE64_V2));  // @@@@ XMEM
        pModuleInfo->SizeOfStruct = sizeof(IMAGEHLP_MODULE64_V2);
// /*@@@@ XMEM*/       free(pData);
        return TRUE;
      }
// /*@@@@ XMEM*/     free(pData);
      return FALSE;
    }
// /*@@@@ XMEM*/   free(pData);
    SetLastError(ERROR_DLL_INIT_FAILED);
    return FALSE;
  }
};

// #############################################################
StackWalker::StackWalker(DWORD dwProcessId, HANDLE hProcess)
{
  this->m_options = OptionsAll;
  this->m_modulesLoaded = FALSE;
  this->m_hProcess = hProcess;
  this->m_sw = new StackWalkerInternal(this, this->m_hProcess);
  this->m_dwProcessId = dwProcessId;
  this->m_szSymPath = NULL;
  this->m_pwos = NULL;
}
StackWalker::StackWalker(int options, LPCSTR szSymPath, DWORD dwProcessId, HANDLE hProcess)
{
  this->m_options = options;
  this->m_modulesLoaded = FALSE;
  this->m_hProcess = hProcess;
  this->m_sw = new StackWalkerInternal(this, this->m_hProcess);
  this->m_dwProcessId = dwProcessId;
  if (szSymPath != NULL)
  {
    this->m_szSymPath = _strdup(szSymPath);
    this->m_options |= SymBuildPath;
  }
  else
    this->m_szSymPath = NULL;
  this->m_pwos = NULL;
}

StackWalker::~StackWalker()
{
  if (m_szSymPath != NULL)
    free(m_szSymPath);
  m_szSymPath = NULL;
  if (this->m_sw != NULL)
    delete this->m_sw;
  this->m_sw = NULL;
}

BOOL StackWalker::LoadModules()
{
  if (this->m_sw == NULL)
  {
    SetLastError(ERROR_DLL_INIT_FAILED);
    return FALSE;
  }
  if (m_modulesLoaded != FALSE)
    return TRUE;

  // Build the sym-path:
  char *szSymPath = NULL;
  if ( (this->m_options & SymBuildPath) != 0)
  {
    const size_t nSymPathLen = 4096;
    szSymPath = (char*) malloc(nSymPathLen);
    if (szSymPath == NULL)
    {
      SetLastError(ERROR_NOT_ENOUGH_MEMORY);
      return FALSE;
    }
    szSymPath[0] = 0;
    // Now first add the (optional) provided sympath:
    if (this->m_szSymPath != NULL)
    {
      strcat_s(szSymPath, nSymPathLen, this->m_szSymPath);
      strcat_s(szSymPath, nSymPathLen, ";");
    }

    strcat_s(szSymPath, nSymPathLen, ".;");

    const size_t nTempLen = 1024;
    char szTemp[nTempLen];
    // Now add the current directory:
    if (GetCurrentDirectoryA(nTempLen, szTemp) > 0)
    {
      szTemp[nTempLen-1] = 0;
      strcat_s(szSymPath, nSymPathLen, szTemp);
      strcat_s(szSymPath, nSymPathLen, ";");
    }

    // Now add the path for the main-module:
    if (GetModuleFileNameA(NULL, szTemp, nTempLen) > 0)
    {
      szTemp[nTempLen-1] = 0;
      for (char *p = (szTemp+strlen(szTemp)-1); p >= szTemp; --p)
      {
        // locate the rightmost path separator
        if ( (*p == '\\') || (*p == '/') || (*p == ':') )
        {
          *p = 0;
          break;
        }
      }  // for (search for path separator...)
      if (strlen(szTemp) > 0)
      {
        strcat_s(szSymPath, nSymPathLen, szTemp);
        strcat_s(szSymPath, nSymPathLen, ";");
      }
    }
    if (GetEnvironmentVariableA("_NT_SYMBOL_PATH", szTemp, nTempLen) > 0)
    {
      szTemp[nTempLen-1] = 0;
      strcat_s(szSymPath, nSymPathLen, szTemp);
      strcat_s(szSymPath, nSymPathLen, ";");
    }
    if (GetEnvironmentVariableA("_NT_ALTERNATE_SYMBOL_PATH", szTemp, nTempLen) > 0)
    {
      szTemp[nTempLen-1] = 0;
      strcat_s(szSymPath, nSymPathLen, szTemp);
      strcat_s(szSymPath, nSymPathLen, ";");
    }
    if (GetEnvironmentVariableA("SYSTEMROOT", szTemp, nTempLen) > 0)
    {
      szTemp[nTempLen-1] = 0;
      strcat_s(szSymPath, nSymPathLen, szTemp);
      strcat_s(szSymPath, nSymPathLen, ";");
      // also add the "system32"-directory:
      strcat_s(szTemp, nTempLen, "\\system32");
      strcat_s(szSymPath, nSymPathLen, szTemp);
      strcat_s(szSymPath, nSymPathLen, ";");
    }

    if ((this->m_options & SymBuildPath) && (this->m_options & SymUseSymSrv))
    {
      if (GetEnvironmentVariableA("SYSTEMDRIVE", szTemp, nTempLen) > 0)
      {
        szTemp[nTempLen-1] = 0;
        strcat_s(szSymPath, nSymPathLen, "SRV*");
        strcat_s(szSymPath, nSymPathLen, szTemp);
        strcat_s(szSymPath, nSymPathLen, "\\websymbols");
        strcat_s(szSymPath, nSymPathLen, "*http://msdl.microsoft.com/download/symbols;");
      }
      else
        strcat_s(szSymPath, nSymPathLen, "SRV*c:\\websymbols*http://msdl.microsoft.com/download/symbols;");
    }
  }

  // First Init the whole stuff...
  BOOL bRet = this->m_sw->Init(szSymPath);
  if (szSymPath != NULL) 
    free(szSymPath); 
  szSymPath = NULL;
  if (bRet == FALSE)
  {
    this->OnDbgHelpErr("Error while initializing dbghelp.dll", 0, 0);
    SetLastError(ERROR_DLL_INIT_FAILED);
    return FALSE;
  }

  bRet = this->m_sw->LoadModules(this->m_hProcess, this->m_dwProcessId);
  if (bRet != FALSE)
    m_modulesLoaded = TRUE;
  return bRet;
}


// The following is used to pass the "userData"-Pointer to the user-provided readMemoryFunction
// This has to be done due to a problem with the "hProcess"-parameter in x64...
// Because this class is in no case multi-threading-enabled (because of the limitations 
// of dbghelp.dll) it is "safe" to use a static-variable
static StackWalker::PReadProcessMemoryRoutine s_readMemoryFunction = NULL;
static LPVOID s_readMemoryFunction_UserData = NULL;

void StackWalker::OstreamRegister( ST_OSTREAMA* pos )
{
  m_pos = pos;
  m_pwos = NULL;
}

void StackWalker::OstreamRegister( ST_OSTREAMW* pwos )
{
  m_pos = NULL;
  m_pwos = pwos;
}

BOOL StackWalker::ShowCallstack(const CONTEXT *context, HANDLE hThread, PReadProcessMemoryRoutine readMemoryFunction, LPVOID pUserData)
{
CONTEXT c;
  CallstackEntry csEntry;
  IMAGEHLP_SYMBOL64 *pSym = NULL;
  StackWalkerInternal::IMAGEHLP_MODULE64_V2 Module;
  IMAGEHLP_LINE64 Line;
  int frameNum;
  char tmpSym[sizeof(IMAGEHLP_SYMBOL64) + STACKWALK_MAX_NAMELEN];    // @@@@ XMEM: temporary buffer, must be defined here because of dimension parameters

  if (m_modulesLoaded == FALSE)
    this->LoadModules();  // ignore the result...

  if (   (this->m_sw == NULL)
      || (this->m_sw->m_hDbhHelp == NULL)
     )
  {
    SetLastError(ERROR_DLL_INIT_FAILED);
    return FALSE;
  }

  s_readMemoryFunction = readMemoryFunction;
  s_readMemoryFunction_UserData = pUserData;

  if (context == NULL)
  {
    // If no context is provided, capture the context
    if (hThread == GetCurrentThread())
    {
      GET_CURRENT_CONTEXT(c, USED_CONTEXT_FLAGS);
    }
    else
    {
      SuspendThread(hThread);
      memset(&c, 0, sizeof(CONTEXT));
      c.ContextFlags = USED_CONTEXT_FLAGS;
      if (GetThreadContext(hThread, &c) == FALSE)
      {
        ResumeThread(hThread);
        return FALSE;
      }
    }
  }
  else
    c = *context;

  // init STACKFRAME for first call
  STACKFRAME64 s; // in/out stackframe
  memset(&s, 0, sizeof(s));
  DWORD imageType;
#ifdef _M_IX86
  // normally, call ImageNtHeader() and use machine info from PE header
  imageType = IMAGE_FILE_MACHINE_I386;
  s.AddrPC.Offset = c.Eip;
  s.AddrPC.Mode = AddrModeFlat;
  s.AddrFrame.Offset = c.Ebp;
  s.AddrFrame.Mode = AddrModeFlat;
  s.AddrStack.Offset = c.Esp;
  s.AddrStack.Mode = AddrModeFlat;
#elif _M_X64
  imageType = IMAGE_FILE_MACHINE_AMD64;
  s.AddrPC.Offset = c.Rip;
  s.AddrPC.Mode = AddrModeFlat;
  s.AddrFrame.Offset = c.Rsp;
  s.AddrFrame.Mode = AddrModeFlat;
  s.AddrStack.Offset = c.Rsp;
  s.AddrStack.Mode = AddrModeFlat;
#elif _M_IA64
  imageType = IMAGE_FILE_MACHINE_IA64;
  s.AddrPC.Offset = c.StIIP;
  s.AddrPC.Mode = AddrModeFlat;
  s.AddrFrame.Offset = c.IntSp;
  s.AddrFrame.Mode = AddrModeFlat;
  s.AddrBStore.Offset = c.RsBSP;
  s.AddrBStore.Mode = AddrModeFlat;
  s.AddrStack.Offset = c.IntSp;
  s.AddrStack.Mode = AddrModeFlat;
#else
#error "Platform not supported!"
#endif

// /*@@@@ XMEM*/ pSym = (IMAGEHLP_SYMBOL64 *) malloc(sizeof(IMAGEHLP_SYMBOL64) + STACKWALK_MAX_NAMELEN);
  pSym = (IMAGEHLP_SYMBOL64 *)tmpSym;
// /*@@@@ XMEM*/ if (!pSym) 
// /*@@@@ XMEM*/   goto cleanup;  // not enough memory...
#if 0
  memset(pSym, 0, sizeof(IMAGEHLP_SYMBOL64) + STACKWALK_MAX_NAMELEN);
#else
  pSym->Address = 0;
  pSym->Size = 0;
  pSym->Flags = 0;
  *pSym->Name = '\0';
#endif