isthreadlast.cpp

This example will show how you can determine if the specified thread is the last thread in the pro

// isthreadlast.cpp (Windows NT/2000)
//
// This example will show how you can determine if the specified thread
// is the last thread in the process or not.
//
// (c)1999 Ashot Oganesyan K, SmartLine, Inc
// mailto:[e-mail], http://www.protect-me.com, http://www.codepile.com

#include <windows.h>
#include <stdio.h>

#define ThreadAmILastThread 12

typedef struct _THREAD_AM_I_LAST_THREAD
{
  BOOL AmILastTread;
} THREAD_AM_I_LAST_THREAD, *PTHREAD_AM_I_LAST_THREAD;


// ntdll!NtQueryInformationThread (NT specific!)
//
// The function copies the thread information of the
// specified type into a buffer
//
// NTSYSAPI
// NTSTATUS
// NTAPI
// NtQueryInformationThread(
//    IN HANDLE ThreadHandle,            // handle to the thread 
//    IN UINT ThreadInformationClass,    // information type
//    OUT PVOID ThreadInformation,       // pointer to buffer
//    IN ULONG ThreadInformationLength,  // buffer size in bytes
//    OUT PULONG ReturnLength OPTIONAL   // pointer to a 32-bit
//                                       // variable that receives
//                                       // the number of bytes
//                                       // written to the buffer 
// );

// ntdll!RtlNtStatusToDosError (NT specific!)
//
// The function translates the Native API errors codes
// to the Win32 error codes
//
// NTSYSAPI
// ULONG
// NTAPI
// RtlNtStatusToDosError(
//    IN NTSTATUS Status // Specifies the error code to translate 
// );

typedef LONG (WINAPI *PROCNTQIT)(HANDLE,UINT,PVOID,ULONG,PULONG);
typedef ULONG (WINAPI *PROCNTSTATUSTODOSERROR)(LONG);

PROCNTQIT NtQueryInformationThread;
PROCNTSTATUSTODOSERROR RtlNtStatusToDosError;

void PrintNtError( char *message, LONG status )
{
  char *errMsg;
  FormatMessage( FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
                 NULL, RtlNtStatusToDosError( status ), 
                 MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), 
                 (LPTSTR) &errMsg, 0, NULL );

  printf("%s: %s\n", message, errMsg );

  LocalFree( errMsg );
}

HANDLE hEvent;

DWORD WINAPI ThreadProc(LPVOID lpParameter)
{
  WaitForSingleObject(hEvent,INFINITE);
  return 0;
}

void main(void)
{
  THREAD_AM_I_LAST_THREAD tinf;
  LONG status;
  HANDLE hTread;
  DWORD Tid;

  RtlNtStatusToDosError = (PROCNTSTATUSTODOSERROR)GetProcAddress(
                                                  GetModuleHandle("ntdll"),
                                                  "RtlNtStatusToDosError"
                                                  );

  NtQueryInformationThread = (PROCNTQIT)GetProcAddress(
                                        GetModuleHandle("ntdll"),
                                        "NtQueryInformationThread"
                                        );

  if (!NtQueryInformationThread || !RtlNtStatusToDosError)
  {
     printf("\nCould not locate the entry points in NTDLL.DLL\n");
     return;
  }

  hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);
  if (hEvent == NULL)
  {
     printf("\nCould not create the event\n");
     return;
  }

  status = NtQueryInformationThread( GetCurrentThread(),
                                     ThreadAmILastThread,
                                     &tinf,sizeof(tinf),0 );
  if (status!=NO_ERROR)
  {
     PrintNtError("Could not get thread information",status);
     return;
  }

  printf("AmILastThread (1-Yes; 0-No) - %d\n",tinf.AmILastTread);

  hTread = CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)ThreadProc,NULL,0,&Tid);
  if (hTread == NULL)
  {
     printf("\nCould not create the thread\n");
     return;
  }

  status = NtQueryInformationThread( GetCurrentThread(),
                                     ThreadAmILastThread,
                                     &tinf,sizeof(tinf),0 );
  if (status!=NO_ERROR)
  {
     PrintNtError("Could not get thread information",status);
     return;
  }

  printf("AmILastThread (1-Yes; 0-No) - %d\n",tinf.AmILastTread);

  SetEvent(hEvent);
  CloseHandle(hTread);
  CloseHandle(hEvent);
}