DEBUG.C

/*++ 
 
Copyright 1996 - 1997 Microsoft Corporation 
 
Module Name: 
 
    debug.c 
 
Abstract: 
 
    Main debug loop for pfmon 
 
Author: 
 
    Mark Lucovsky (markl) 26-Jan-1995 
 
Revision History: 
 
--*/ 
 
#include "pfmonp.h" 
 
DWORD 
DebugEventHandler( 
    LPDEBUG_EVENT DebugEvent 
    ); 
 
VOID 
DebugEventLoop( VOID ) 
{ 
    DEBUG_EVENT DebugEvent; 
    DWORD ContinueStatus; 
    DWORD OldPriority; 
 
    // 
    // We want to process debug events quickly 
    // 
 
    OldPriority = GetPriorityClass( GetCurrentProcess() ); 
    SetPriorityClass( GetCurrentProcess(), HIGH_PRIORITY_CLASS ); 
 
    do { 
retry_debug_wait: 
        ProcessPfMonData(); 
        if (!WaitForDebugEvent( &DebugEvent, 500 )) { 
            if ( GetLastError() == ERROR_SEM_TIMEOUT ) { 
                goto retry_debug_wait; 
                } 
            DeclareError( PFMON_WAITDEBUGEVENT_FAILED, GetLastError() ); 
            ExitProcess( 1 ); 
            } 
        ProcessPfMonData(); 
        if ( fVerbose ) { 
            if (DebugEvent.dwDebugEventCode == EXCEPTION_DEBUG_EVENT) { 
                fprintf(stderr,"Debug exception event - Code: %x  Address: %x  Info: [%u] %x %x %x %x\n", 
                        DebugEvent.u.Exception.ExceptionRecord.ExceptionCode, 
                        DebugEvent.u.Exception.ExceptionRecord.ExceptionAddress, 
                        DebugEvent.u.Exception.ExceptionRecord.NumberParameters, 
                        DebugEvent.u.Exception.ExceptionRecord.ExceptionInformation[ 0 ], 
                        DebugEvent.u.Exception.ExceptionRecord.ExceptionInformation[ 1 ], 
                        DebugEvent.u.Exception.ExceptionRecord.ExceptionInformation[ 2 ], 
                        DebugEvent.u.Exception.ExceptionRecord.ExceptionInformation[ 3 ] 
                        ); 
                } 
            else { 
                fprintf(stderr,"Debug %x event\n", DebugEvent.dwDebugEventCode); 
                } 
            } 
 
        ContinueStatus = DebugEventHandler( &DebugEvent ); 
 
        if ( fVerbose ) { 
            fprintf(stderr,"Continue Status %x\n", ContinueStatus); 
            } 
 
        if (!ContinueDebugEvent( DebugEvent.dwProcessId, 
                                 DebugEvent.dwThreadId, 
                                 ContinueStatus 
                               ) 
           ) { 
            DeclareError( PFMON_CONTDEBUGEVENT_FAILED, GetLastError() ); 
            ExitProcess( 1 ); 
            } 
        } 
    while (!IsListEmpty( &ProcessListHead )); 
 
 
    // 
    // Drop back to old priority to interact with user. 
    // 
 
    SetPriorityClass( GetCurrentProcess(), OldPriority ); 
} 
 
DWORD 
DebugEventHandler( 
    LPDEBUG_EVENT DebugEvent 
    ) 
{ 
    DWORD ContinueStatus; 
    PPROCESS_INFO Process; 
    PTHREAD_INFO Thread; 
    CONTEXT Context; 
    PCONTEXT pContext; 
 
 
    ContinueStatus = (DWORD)DBG_CONTINUE; 
    if (FindProcessAndThreadForEvent( DebugEvent, &Process, &Thread )) { 
        switch (DebugEvent->dwDebugEventCode) { 
            case CREATE_PROCESS_DEBUG_EVENT: 
                // 
                // Create process event includes first thread of process 
                // as well.  Remember process and thread in our process tree 
                // 
 
                if (AddProcess( DebugEvent, &Process )) { 
                    AddModule( DebugEvent ); 
                    AddThread( DebugEvent, Process, &Thread ); 
                    } 
                break; 
 
            case EXIT_PROCESS_DEBUG_EVENT: 
                // 
                // Exit process event includes last thread of process 
                // as well.  Remove process and thread from our process tree 
                // 
 
                if (DeleteThread( Process, Thread )) { 
                    DeleteProcess( Process ); 
                    } 
                break; 
 
            case CREATE_THREAD_DEBUG_EVENT: 
                // 
                // Create thread.  Remember thread in our process tree. 
                // 
 
                AddThread( DebugEvent, Process, &Thread ); 
                break; 
 
            case EXIT_THREAD_DEBUG_EVENT: 
                // 
                // Exit thread.  Remove thread from our process tree. 
                // 
 
                DeleteThread( Process, Thread ); 
                break; 
 
            case LOAD_DLL_DEBUG_EVENT: 
                AddModule( DebugEvent ); 
                break; 
 
            case UNLOAD_DLL_DEBUG_EVENT: 
                break; 
 
            case OUTPUT_DEBUG_STRING_EVENT: 
            case RIP_EVENT: 
                // 
                // Ignore these 
                // 
                break; 
 
            case EXCEPTION_DEBUG_EVENT: 
                // 
                // Assume we wont handle this exception 
                // 
 
                ContinueStatus = (DWORD)DBG_CONTINUE; 
                switch (DebugEvent->u.Exception.ExceptionRecord.ExceptionCode) { 
                    // 
                    // Breakpoint exception. 
                    // 
 
                    case STATUS_BREAKPOINT: 
                            Context.ContextFlags = CONTEXT_FULL; 
 
                            if (!GetThreadContext( Thread->Handle, &Context )) { 
                                fprintf(stderr,"Failed to get context for thread %x (%x) - %u\n", Thread->Id, Thread->Handle, GetLastError()); 
                                ExitProcess(1); 
                                } 
                            pContext = &Context; 
                            CONTEXT_TO_PROGRAM_COUNTER(pContext) = (ULONG)((PCHAR)DebugEvent->u.Exception.ExceptionRecord.ExceptionAddress + BPSKIP); 
 
                            if (!SetThreadContext( Thread->Handle, &Context )) { 
                                fprintf(stderr,"Failed to set context for thread %x (%x) - %u\n", Thread->Id, Thread->Handle, GetLastError()); 
                                ExitProcess(1); 
                                } 
 
                        break; 
 
                    default: 
                        ContinueStatus = (DWORD) DBG_EXCEPTION_NOT_HANDLED; 
                        if ( fVerbose ) { 
                            fprintf(stderr,"Unknown exception: %08x at %08x\n", 
                                    DebugEvent->u.Exception.ExceptionRecord.ExceptionCode, 
                                    DebugEvent->u.Exception.ExceptionRecord.ExceptionAddress 
                                    ); 
                            } 
                        break; 
                    } 
                break; 
 
            default: 
                break; 
            } 
        } 
    return( ContinueStatus ); 
}