viewer.c

/*
 * viewer.c  -  BER.exe
 *   Crash-dump viewer launched by BERDebugger.exe.
 */

#include "common.h"
#include "viewer.h"

#define ID_EDIT  100
#define ID_OK    101

/* Global handles used in WndProc */
static HWND s_hEdit = NULL;
static HWND s_hOK   = NULL;
static HWND s_hWnd  = NULL;

/* ---------------------------------------------------------------
 * WndProc
 * ------------------------------------------------------------- */
static LRESULT CALLBACK WndProc(HWND hWnd, UINT message,
                                 WPARAM wParam, LPARAM lParam)
{
    switch (message)
    {
        case WM_CREATE:
        {
            RECT rc;
            GetClientRect(hWnd, &rc);

            /* Multi-line read-only edit for the register dump */
            s_hEdit = CreateWindow(
                L"EDIT", L"",
                WS_CHILD | WS_VISIBLE | WS_VSCROLL |
                ES_MULTILINE | ES_READONLY | ES_AUTOVSCROLL,
                0, 0, rc.right, rc.bottom - 45,
                hWnd, (HMENU)ID_EDIT,
                ((LPCREATESTRUCT)lParam)->hInstance, NULL);

            /* OK button at the bottom-centre */
            s_hOK = CreateWindow(
                L"BUTTON", L"OK",
                WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON | BS_DEFPUSHBUTTON,
                rc.right / 2 - 50, rc.bottom - 40, 100, 32,
                hWnd, (HMENU)ID_OK,
                ((LPCREATESTRUCT)lParam)->hInstance, NULL);

            /* Use a fixed-pitch font so register columns line up */
            {
                HFONT hFont = (HFONT)GetStockObject(SYSTEM_FIXED_FONT);
                if (hFont)
                    SendMessage(s_hEdit, WM_SETFONT, (WPARAM)hFont, FALSE);
            }
            break;
        }

        case WM_SIZE:
        {
            int w = LOWORD(lParam);
            int h = HIWORD(lParam);
            if (s_hEdit) MoveWindow(s_hEdit, 0, 0, w, h - 45, TRUE);
            if (s_hOK)   MoveWindow(s_hOK, w / 2 - 50, h - 40, 100, 32, TRUE);
            break;
        }

        case WM_COMMAND:
            if (LOWORD(wParam) == ID_OK)
                PostQuitMessage(0);
            break;

        case WM_COPYDATA:
        {
            const COPYDATASTRUCT *cds = (const COPYDATASTRUCT *)lParam;
            if (cds->dwData == COPYDATA_KEY &&
                cds->cbData == sizeof(BERExceptionContext_t))
            {
                const BERExceptionContext_t *dump = (const BERExceptionContext_t *)cds->lpData;
                WCHAR *buf = (WCHAR *)LocalAlloc(LMEM_ZEROINIT,
                                                  4096 * sizeof(WCHAR));
                if (buf != NULL)
                {
                    FormatDump(buf, 4096, dump);
                    SetWindowText(s_hEdit, buf);
                    LocalFree(buf);
                }

                /* Now reveal the window */
                ShowWindow(hWnd, SW_SHOWNORMAL);
                UpdateWindow(hWnd);
                SetForegroundWindow(hWnd);
            }
            return TRUE;
        }

        case WM_DESTROY:
            PostQuitMessage(0);
            break;

        default:
            return DefWindowProc(hWnd, message, wParam, lParam);
    }
    return 0;
}

/* ---------------------------------------------------------------
 * RunViewer
 * ------------------------------------------------------------- */
int RunViewer(HINSTANCE hInstance, int nCmdShow, DWORD processId)
{
    WNDCLASS wc;
    HWND     hWnd;
    WCHAR    eventName[64];
    HANDLE   hEvent;
    DWORD    waitResult;
    MSG      msg;
    int      screenW, screenH;

    (void)nCmdShow;

    /* Register window class */
    memset(&wc, 0, sizeof(wc));
    wc.style         = CS_HREDRAW | CS_VREDRAW;
    wc.lpfnWndProc   = WndProc;
    wc.hInstance     = hInstance;
    wc.hIcon         = LoadIcon(NULL, IDI_APPLICATION);
    wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
    wc.lpszClassName = WINDOW_CLASS;

    if (!RegisterClass(&wc))
    {
        AppendLog(L"Viewer: RegisterClass failed");
        return EXIT_FAILURE;
    }

    /* Use full screen size */
    screenW = GetSystemMetrics(SM_CXSCREEN);
    screenH = GetSystemMetrics(SM_CYSCREEN);

    /* Create window - hidden until WM_COPYDATA arrives */
    hWnd = CreateWindow(
        WINDOW_CLASS,
        L"BER - Brain Exception Reporter",
        WS_CAPTION | WS_SYSMENU | WS_SIZEBOX,
        0, 0, screenW, screenH,
        NULL, NULL, hInstance, NULL);

    if (hWnd == NULL)
    {
        AppendLog(L"Viewer: CreateWindow failed");
        return EXIT_FAILURE;
    }

    s_hWnd = hWnd;

    /* Open (or create) the named event that BERDebugger will signal */
    wsprintf(eventName, EVENT_NAME_FMT, processId);
    hEvent = CreateEvent(NULL, TRUE, FALSE, eventName);
    if (hEvent == NULL)
    {
        AppendLog(L"Viewer: CreateEvent failed");
        DestroyWindow(hWnd);
        return EXIT_FAILURE;
    }

    /* Block up to 5 seconds waiting for BERDebugger to signal us */
    waitResult = WaitForSingleObject(hEvent, 5000);
    CloseHandle(hEvent);

    if (waitResult == WAIT_TIMEOUT)
    {
        /* BERDebugger did not signal in time - exit silently */
        DestroyWindow(hWnd);
        return EXIT_FAILURE;
    }

    /*
     * Event fired: BERDebugger has found our window and is about to
     * send WM_COPYDATA.  Enter the message loop; WndProc will show
     * the window once the data arrives.
     */
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    return (int)msg.wParam;
}

/* ---------------------------------------------------------------
 * WinMain  -  BER.exe entry point
 * ------------------------------------------------------------- */
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
                   LPWSTR lpszCmdLine, int nCmdShow)
{
    DWORD processId;

    (void)hPrevInstance;

    /* Argument must be "0x<hex>" */
    if (lstrlenW(lpszCmdLine) <= 2 ||
        lpszCmdLine[0] != L'0'     ||
        lpszCmdLine[1] != L'x')
    {
        return EXIT_FAILURE;
    }

    swscanf(&lpszCmdLine[2], L"%lx", &processId);

    return RunViewer(hInstance, nCmdShow, processId);
}