Is there any api's which load a crash dump, symbols from the symbol store and then allow programmatic access to the information?
I want to create a tool to auto process crash dumps and produce a report based on them.
Use a command file for Windbg which sets up your configs and then runs !analyze. Set windbg to output to a file (as described here: windbg: Command output to text file)
Then you can enjoy trying to sort, categorize, etc. the output from that. !analyzewill do a decent job of analyzing most crashes. If it can't, I doubt you'd be doing a better job with your own code, unless you have a lot of experience in analyzing crash logs by program (I haven't ever tried, although I have a decent idea of what to look for, I wouldn't necessarily want to write code to actually do it - I have written code to write logs when the system has crashed, so I know what you usually need).
The Windows dbghelp API loads symbols and line number information to support making stack back traces. Do not know API for reading crash dump files.
Debug diagnostic tool has a com interface that can load a dump, process it using symbols and give you the information back.
http://www.microsoft.com/en-au/download/details.aspx?id=26798
Tutorial: http://codenasarre.wordpress.com/2011/06/14/how-to-control-a-debugger-engine/
Related
I have an ARM Cortex-M4 embedded system running FreeRTOS. I have implemented a crash log dump mechanism that writes a file to a storage device in the event of a fatal error, such as divide-by-zero, null-pointer, address errors, invalid instruction, or assertions. In this file, I write, among other things, the contents of the stack at the time of the exception.
This system captures crashes that happen in the field, so the idea is to analyze the crashes that are returned to me and determine the source of the problem as best I can. I can easily connect the log to the .elf that was generated when that version of the code was compiled. I just need a way to parse it.
I assume there are tools that can do this already (I can't be the first to do this), but I'm having trouble finding something on The Series of Tubes(tm) that fits the bill.
Is there a good starting point to create a tool that can parse the .elf from compilation and follow a stack dump to create such a report?
For the benefit of anyone else with this problem, here's what I am doing:
Google has a tool called "breakpad" that can parse .elf and crashlog files in the "minidump" format, which was originally created by Microsoft and adapted by Google for Chrome.
I am writing a tool to convert my stack traces to minidump format in the hopes of using the breakpad tools to analyze my crash logs.
Here's a link to breakpad: https://github.com/google/breakpad/blob/master/docs/getting_started_with_breakpad.md
I need to read information, code, flags, address, etc from a memory.dmp file generated from a windows BSOD through C++. The basic idea is that status info can be requested from a remote site and one of the requested pieces of information is some basic info from the last BSOD that occured on the machine thus I need to open the kernel/memory dump file through C++ (Im using MSVC 2005).
Start here, then realize using scripted commands in WinDBG is much easier.
Note: you only need WinDBG on the analysis machine, not the crashing one. You retrieve the minidump and analyse it externally. The only difficulty you will have is getting the right symbols - for Windows, Microsoft makes them available via their symbol servers, but applications that caused the crash may not supply the right symbols you need. IF they are you own applications causing the crash, get a symbol server and use it.
I would configure Windows to create small kernel memory dumps which will include the parameter of the bugcheck you are after.
On XP it was 64KB on my Win8.1 x64 it is 256KB. These files compress well. You should be able to get away with a zip file of 10-60KB size depending on the bitness of the OS. If bandwidth is of of utmost importance to you, you can use 7z which compresses about 50% better than the plain zip algo at the expense of much longer compression times (5-6 longer) but for such small files the CPU time difference should be irrelevant.
If you do not want your users to configure dump reporting you need to set the DWORD
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\CrashControl
to 3 for a small kernel dump programatically.
For an explanation of the values see http://technet.microsoft.com/en-us/library/cc976050.aspx
0 Debugging information is not written to a file.
1 Complete crash dump is written to a file.
2 Kernel memory dump is written to a file.
3 Small memory dump is written to a file.
You will then get by default a small kernel dump in %SystemRoot%\MEMORY.DMP.
I've developed a program by a customer who's experiencing when he do a certain operation. This isn't happening always on the same place and on the same data and, moreover, it is not happening nor in my local developing machine nor in my test Virtual Machine (which is free of all developing equipment).
Given these conditions, I've decided to compile with MAP (enabled in Configuring Properties-> Linker->Debugger with option /MAP) to see which function is causing crash.
If I've correctly understood, when the program crash I've to check down the offset error and then, search in my MAP under the column RVA+BASE:
Address Publics by Value Rva+Base Lib:Object
0001:00037af0 ?PersonalizzaPlancia#CDlgGestioneDatiProgetto#MosaicoDialogs##IAEXXZ 00438af0 f DlgGestioneDatiProgetto.obj
0001:00038000 ?SalvaTemporanei#CDlgGestioneDatiProgetto#MosaicoDialogs##IAEXXZ 00439000 f DlgGestioneDatiProgetto.obj
Actually, my crash happens at offset: 00038C90 So I should think that it's somewhere in the method:
MosaicoDialogs::CDlgGestioneDatiProgetto::PersonalizzaPlancia
but this is not absolutely possible, so assuming that the computer can't be wrong, I'm the one who's doing it bad.
Can someone explain me how to read MAP in correct way?
don't bother - instead, build the project with symbols enabled and strip them into a pdb file.
Modify the program a little, to write a minidump when it crashes using a unhandled exception handler
Give the newly compiled program to the customer, and when it crashes call MiniDumpWriteDump.
Ask the customer to send this .dmp file to you, and you then simply load it up in Visual Studio (or WinDbg) and it will match up the symbols to the program, and will also match up the code. You should be able to see the exact line of code and some of the variables involved. (if using VS, when you load the .dmp file, top right corner will be an option to "start debugging" click that as it will 'start debugging' at the point of the crash)
Try it first locally - put a div by zero error somewhere in your program and see if you can debug the dump after its been run. Note that you must keep the exact same symbol file for each build of your program - they match exactly. You cannot expect a symbol file for one build to match another build, even if nothing changed.
There are tutorials for this kind of thing, such as this one from CodeProject that looks like it describes what you need.
Reading of MAP files to find out crash location is explained nicely in this code project article.
http://www.codeproject.com/Articles/3472/Finding-crash-information-using-the-MAP-file
Hope helps.
For postmortem debugging, there's an alternative that would not required the use of a map file. Rather, it would require you to create a simple registry script to enable some WER (Windows Error Reporting) flags to trap the crash dump file. First, build your application with debug symbols. Then, follow the instructions for Collecting User-Mode Dumps. Basically, you create a sub key under the "LocalDumps" key. This sub key must be the name of your application, for example, "myapplication.exe". Then, create the "DumpCount", "DumpType", and "DumpFolder" keys/values. Have the user run the registry script. This will enable trapping the dump locally. Then, have the user force the crash to collect the dump file. The user can then send the dump file to you to debug using the symbols you created earlier. Lastly, you'll need to create a registry script that removes the keys/values you added to the registry.
We have a problem for which I am looking for a direction. We have an old MFC based application, and due to various reasons, the application is crashing sometimes intermittently in some weird scenarios. And even the customers who are using our application and getting these crashes are finding difficulty in identifying the pattern of crash. So, I had a thought that, if we can have a mechanism by which we can generate a log whenever the application crashes. Like for example, the call stack or any other information in that log. I know,, we can use the crash dump in this case, but then I feel like having a log is a better option. So any help or information in this regard would be really helpful.
Thank you.
You can find a good implementation of crash reporter in the link here.
When you compile your release build, make sure that both DEBUG and /MAP are enabled. Store your binaries together with your .map files and let your customer run this version until a crash is produced. In the Event Viewer you will then find a crash log with a crash offset. Then debug step into your code (F10) and use the crash offset together with some nifty tricks and tricks to jump (set the EIP register to... well, you have to google this a bit) to the location where the crash occurred. You should now be able to find the error!
If my C++ app crashes on Windows I want to send useful debugging information to our server.
On Linux I would use the GNU backtrace() function - is there an equivalent for Windows?
Is there a way to extract useful debugging information after a program has crashed? Or only from within the process?
(Advice along the lines of "test you app so it doesn't crash" is not helpful! - all non-trivial programs will have bugs)
The function Stackwalk64 can be used to snap a stack trace on Windows.
If you intend to use this function, you should be sure to compile your code with FPO disabled - without symbols, StackWalk64 won't be able to properly walk FPO'd frames.
You can get some code running in process at the time of the crash via a top-level __try/__except block by calling SetUnhandledExceptionFilter. This is a bit unreliable since it requires you to have code running inside a crashed process.
Alternatively, you can just the built-in Windows Error Reporting to collect crash data. This is more reliable, since it doesn't require you to add code running inside the compromised, crashed process. The only cost is to get a code-signing certificate, since you must submit a signed binary to the service. https://sysdev.microsoft.com/en-US/Hardware/signup/ has more details.
You can use the Windows API call MiniDumpWriteDump if you wish to roll your own code. Both Windows XP and Vist automate this process and you can sign up at https://winqual.microsoft.com to gain access to the error reports.
Also check out http://kb.mozillazine.org/Breakpad and http://www.codeproject.com/KB/debug/crash_report.aspx for other solutions.
This website provides quite a detailed overview of stack retrieval on Win32 after a C++ exception:
http://www.eptacom.net/pubblicazioni/pub_eng/except.html
Of course, this will only work from within the process, so if the process gets terminated or crashes to the point where it terminates before that code is run, it won't work.
Generate a minidump file. You can then load it up in windbg or Visual Studio and inspect the entire stack where the crash occurred.
Here's a good place to start reading.
Its quite simple to dump the current stackframe addresses into a log file. All you have to do is get such a function called on program faults (i.e. a interrupt handler in Windows) or asserts. This can be done at released versions as well. The log file then can be matched with a map file resulting in a call stack with function names.
I published a article about this some years ago.
See http://www.ddj.com/architect/185300443
Let me describe how I handle crashes in my C++/WTL application.
First, in the main function, I call _set_se_translator, and pass in a function that will throw a C++ exception instead of using structured windows exceptions. This function gets an error code, for which you can get a Windows error message via FormatMessage, and a PEXCEPTION_POINTERS argument, which you can use to write a minidump (code here). You can also check the exception code for certain "meltdown" errors that you should just bail from, like EXCEPTION_NONCONTINUABLE_EXCEPTION or EXCEPTION_STACK_OVERFLOW :) (If it's recoverable, I prompt the user to email me this minidump file.)
The minidump file itself can be opened in Visual Studio like a normal project, and providing you've created a .pdb file for your executable, you can run the project and it'll jump to the exact location of the crash, together with the call stack and registers, which can be examined from the debugger.
If you want to grab a callstack (plus other good info) for a runtime crash, on a release build even on site, then you need to set up Dr Watson (run DrWtsn32.exe). If you check the 'generate crash dumps' option, when an app crashes, it'll write a mini dump file to the path specified (called user.dmp).
You can take this, combine it with the symbols you created when you built your server (set this in your compiler/linker to generate pdb files - keep these safe at home, you use them to match the dump so they can work out the source where the crash occurred)
Get yourself windbg, open it and use the menu option to 'load crash dump'. Once it's loaded everything you can type '~#kp' to get a callstack for every thread (or click the button at the top for the current thread).
There's good articles to know how to do this all over the web, This one is my favourite, and you'll want to read this to get an understanding of how to helpyourself manage the symbols really easily.
You will have to set up a dump generation framework in your application, here is how you may do it.
You may then upload the dump file to the server for further analysis using dump analyzers like windbg.
You may want to use adplus to capture the crash callstack.
You can download and install Debugging tools for Windows.
Usage of adplus is mentioned here:
Adplus usage
This creates the complete crash or hang dump. Once you have the dump, Windbg comes to the rescue. Map the correct pdbs and symbols and you are all set to analyze the dump. To start with use the command "!analyze -v"