Create a dump file for an application whenever it crashes

Question

I am trying to create a dump file for my application whenever it crashes. I am currently using procdump.exe with -e flag in order to do it, so if I have unhandled exception in my application procdump creates a dump file for me.

I thought that I was done, but then I found out that my application crashes and procdump doesn’t create a dump file. After some investigations I have found out that invalid use of vector::front causes runtime error. I turned on the _SECURE_SCL_THROWS flag and after that procdump.exe -e did catch the crash and created a dump file.

Now to my question: Is now procdump.exe -e will always create a dump file when my application crashes? How can I guarantee that I don’t have any other scenarios where procdump -e is not good for me?

Answer 1

I assume you are on a windows environment (because you use procdump.exe). You could also set an exception filter for your programm that writes a mindump whenever your application crash:

1. Register a callback function using SetUnhandledExceptionFilter which will be invoked on a crash. A possible signature would be:

   LONG WINAPI HandleException(struct _EXCEPTION_POINTERS* apExceptionInfo)
   

   Register it somewhere using:

   SetUnhandledExceptionFilter(HandleException);   
   

2. Define a function pointer to call the Function MiniDumpWriteDump:

   typedef BOOL (WINAPI *MINIDUMPWRITEDUMP)(HANDLE hProcess, DWORD dwPid, HANDLE hFile, MINIDUMP_TYPE DumpType,CONST PMINIDUMP_EXCEPTION_INFORMATION ExceptionParam,CONSTPMINIDUMP_USER_STREAM_INFORMATIOUserStreamParam,CONST PMINIDUMP_CALLBACK_INFORMATION CallbackParam);
   

3. Use the MiniDumpWriteDump function to write the dump (requires DbgHelp.dll 5.1 or later) in the previously registerd callback method (HandleException):

   HMODULE mhLib = ::LoadLibrary(_T("dbghelp.dll"));
   MINIDUMPWRITEDUMP pDump = (MINIDUMPWRITEDUMP)::GetProcAddress(mhLib, "MiniDumpWriteDump");
   
   HANDLE  hFile = ::CreateFile(_T("dump_name"), GENERIC_WRITE, FILE_SHARE_WRITE, NULL, CREATE_ALWAYS,
                       FILE_ATTRIBUTE_NORMAL, NULL);
   
   
   _MINIDUMP_EXCEPTION_INFORMATION ExInfo;
   ExInfo.ThreadId = ::GetCurrentThreadId();
   ExInfo.ExceptionPointers = apExceptionInfo;
   ExInfo.ClientPointers = FALSE;
   
   pDump(GetCurrentProcess(), GetCurrentProcessId(), hFile, MiniDumpNormal, &ExInfo, NULL, NULL);
   ::CloseHandle(hFile);
   

Answer 2

Or use Windows' built in error reporting, WER, by adding a key to registry, to enable it for your app. More details here: https://learn.microsoft.com/en-us/windows/win32/wer/collecting-user-mode-dumps

Answer 3

/* WinDump.cpp */

#ifdef WIN32

#include <windows.h>
#include <Dbghelp.h>
#include <tchar.h>


typedef BOOL (WINAPI *MINIDUMPWRITEDUMP)(HANDLE hProcess, DWORD dwPid, HANDLE hFile, MINIDUMP_TYPE DumpType,CONST PMINIDUMP_EXCEPTION_INFORMATION ExceptionParam,CONST PMINIDUMP_USER_STREAM_INFORMATION UserStreamParam,CONST PMINIDUMP_CALLBACK_INFORMATION CallbackParam);

void create_minidump(struct _EXCEPTION_POINTERS* apExceptionInfo)
{
    HMODULE mhLib = ::LoadLibrary(_T("dbghelp.dll"));
    MINIDUMPWRITEDUMP pDump = (MINIDUMPWRITEDUMP)::GetProcAddress(mhLib, "MiniDumpWriteDump");

    HANDLE  hFile = ::CreateFile(_T("core.dmp"), GENERIC_WRITE, FILE_SHARE_WRITE, NULL, CREATE_ALWAYS,
        FILE_ATTRIBUTE_NORMAL, NULL);

    _MINIDUMP_EXCEPTION_INFORMATION ExInfo;
    ExInfo.ThreadId = ::GetCurrentThreadId();
    ExInfo.ExceptionPointers = apExceptionInfo;
    ExInfo.ClientPointers = FALSE;

    pDump(GetCurrentProcess(), GetCurrentProcessId(), hFile, MiniDumpNormal, &ExInfo, NULL, NULL);
    ::CloseHandle(hFile);
}

LONG WINAPI unhandled_handler(struct _EXCEPTION_POINTERS* apExceptionInfo)
{
    create_minidump(apExceptionInfo);
    return EXCEPTION_CONTINUE_SEARCH;
}

#endif // WIN32

/* WinDump.h */

#ifdef WIN32

LONG WINAPI unhandled_handler(struct _EXCEPTION_POINTERS* apExceptionInfo);

#endif // WIN32

/* main.cpp */

#include "WinDump.h"

int main(int argc, char **argv)
{

    // Create a dump file whenever the gateway crashes only on windows
    SetUnhandledExceptionFilter(unhandled_handler);
    return 0;
}