Detecting a process crash in C++/Win32 - c++

Question

I'm working on a software that contains 2 programs : the Qt Main exe + an OpenGL Game exe
We use always the Qt Main exe at the first. When we click on the button "start game", we execute the OpenGL Game exe. No probleme to do that.
The problem is that sometime we have a crash in the OpenGL Game exe and we want to send a crash report containing the log to our compagny crash-report mail.
I found a function (registerwaitforsingleobject) in Win32 API but I don't know if the process has crashed or not :
https://learn.microsoft.com/en-gb/windows/desktop/api/winbase/nf-winbase-registerwaitforsingleobject
I would like to use only the win32 api (WinXP-WinVist to Win10)
Thanks in advance

Answer 1

I found the solution to my problem : I used GetExitCodeProcess function from the Win32 API (https://learn.microsoft.com/en-us/windows/desktop/api/processthreadsapi/nf-processthreadsapi-getexitcodeprocess).
This is the example code :
int main(int argc, char** arv)
{
STARTUPINFO si;
PROCESS_INFORMATION pi;
ZeroMemory(&si, sizeof(si));
si.cb = sizeof(si);
ZeroMemory(&pi, sizeof(pi));
const char * prgm = "CrashedProcess.exe";
LPSTR prgmLpstr = const_cast<LPSTR>(prgm);
// Start the child process.
if (!CreateProcess(NULL, // No module name (use command line)
prgmLpstr, // Command line
NULL, // Process handle not inheritable
NULL, // Thread handle not inheritable
FALSE, // Set handle inheritance to FALSE
0, // No creation flags
NULL, // Use parent's environment block
NULL, // Use parent's starting directory
&si, // Pointer to STARTUPINFO structure
&pi) // Pointer to PROCESS_INFORMATION structure
)
{
printf("CreateProcess failed (%d).\n", GetLastError());
return -1;
}
// Wait until child process exits.
auto ret = WaitForSingleObject(pi.hProcess, INFINITE);
printf("WaitForSingleObject ret = %x\n", ret);
if (ret == WAIT_OBJECT_0)
{
printf("WaitForSingleObject ret ret == WAIT_OBJECT_0\n");
}
BOOL b = FALSE;
DWORD n = 0;
b = GetExitCodeProcess(pi.hProcess, &n);
if (n == 0xC0000005)
{
printf("Process Crashed !!!\n");
}
// Close process and thread handles.
CloseHandle(pi.hProcess);
CloseHandle(pi.hThread);
printf("WaitForSingleObject end\n");
return 0;
}
CrashedProcess.exe source code :
int main()
{
int * ptr = nullptr;
*ptr = 123;
return 0;
}

Answer 2

Use a ready-made solution such as CrashRpt http://crashrpt.sourceforge.net/. It will install a proper handler and report/submit what you need when exceptions are thrown.

Answer 3

You can use Interprocess Communications with a pipe.
Send a message at time laps (for example, 1 second). If there's no response you can be almost sure that the other program is crashed.
Another approach, less elegant, is testing for a log file, modified every x-seconds, with a value meaning "I'm still alive, not crashed".

Answer 4

Assuming the program you care about has a normal Windows event loop, the more or less standard way to check that it's processing messages in a reasonably timely fashion is to use SendMessageTimeout to send it a WM_NULL message.
The program won't do anything in response to the WM_NULL, but SendMessageTimeout will time out if the message stays in its message queue for too long (where you pick what "too long" means when you make the call). So you send it, and then check whether it timed out or not.
But note: this only applies to programs that does process Windows messages. If it doesn't have a message loop, it'll always timeout. Oh, and a program is multi-threaded, one thread can "crash" (e.g., go into an infinite loop) while others continue to operate normally, so it's not always easy to even define what "crashed" means.