Amiga Format CD 10/amigaformatcd10.iso/-look_here_1st!-/handy_tools/snoopdos/snoopdos_source/mainwin.c

C/C++ Source or Header | 1994-09-17 | 148KB | 5,220 lines

/*
 *        MAINWIN.C                                            vi:ts=4
 *
 *      Copyright (c) Eddy Carroll, September 1994.
 *
 *        This module handles the main SnoopDos window, outputting new events
 *        to the window, menu options, etc.
 */

#include "system.h"
#include "snoopdos.h"
#include "gui.h"

#if 0
#define DB(s)    KPrintF(s)
#else
#define DB(s)
#endif

/*
 *        In earlier versions, we used to lock layers whenever we rendered
 *        event output to the SnoopDos main window buffer. This avoided
 *        deadlocks with input.device. Now we use a different work around,
 *        but for the sake of documentation, we leave the original calls
 *        in (you never know when they might come in handy)
 *
 *        (The different workaround is to never monitor tasks that have
 *        locked layers on the SnoopDos screen/window).
 */
#if 0
#define LOCK_LAYERS    \
    (LockLayerInfo(&MainWindow->WScreen->LayerInfo),    \
     LockLayer(0, MainWindow->RPort->Layer))

#define UNLOCK_LAYERS \
    (UnlockLayer(MainWindow->RPort->Layer),    \
     UnlockLayerInfo(&MainWindow->WScreen->LayerInfo))

#else
#define LOCK_LAYERS
#define UNLOCK_LAYERS
#endif


/*
 *        Interface to RawPutChar() in exec.library
 *        (It takes a single parameter in D0)
 */
#pragma libcall SysBase RawPutChar 204 001

/*
 *        These two are imported from SNOOPDOS.C
 */
extern char    Version[];
extern char SnoopDosTitle[];
extern char SnoopDosTitleKey[];

/*
 *        Global vars used by the main window
 */
struct Gadget        *MainGadList;        /* Main gadget list            */
struct Menu            *MainWinMenu;        /* Main window menu            */
struct TextFont        *BufferFont;        /* Handle for buffer font    */
struct TextAttr        *CurMainGadgetFA;    /* Current gadget font attr    */
struct TextAttr        *CurMainBufferFA;    /* Current buffer font attr    */

struct RastPort        InvertRP;            /* Used when sizing columns    */

int NumBufLines;            /* Current number of lines in buffer    */
int ChangedSpacing;            /* 1 = edited spacing since last redraw    */
int ScrollDirection;        /* ID of current scroll gadget, or 0    */
int ScrollCount;            /* Used for pacing INTUITICKS in scroll    */
int RemovedGadgets;            /* True if gadgets removed from window    */
int AwaitingResize;            /* True if waiting for window resize    */

#define RESIZE_DONE        0    /* Resize is now complete                */
#define RESIZE_MIDDLE    1    /* Resize happened in middle of buffer    */
#define RESIZE_BOTTOM    2    /* Resize happened at end of buffer        */

#define MOVECOL_FREE    0    /* Reposition column freely                */
#define MOVECOL_FIXED    1    /* Reposition column fixed wrt RHS col    */

#define INVERT_HEADER    0    /* Invert only the header part of col    */
#define INVERT_FULLBOX    1    /* Invert entire column                  */

int    BoxLeft;                /* Pixel offset of left edge of box        */
int    BoxTop;                    /* Pixel offset of top edge of box        */
int    BoxWidth;                /* Width of box in pixels                */
int    BoxHeight;                /* Height of box in pixels                */
int    BoxHeaderLine;            /* Baseline for box header text            */
int    BoxInLeft;                /* Pixel offset of inside top of box    */
int    BoxInTop;                /* Pixel offset of inside left of box    */
int    BoxInWidth;                /* Inside width of box                    */
int    BoxInHeight;            /* Inside height of box                    */
int    BoxCharWidth;            /* Width of a single character in box    */
int BoxCharHeight;            /* Height of a single character in box    */
int    BoxCols;                /* Number of columns of text in box        */
int    BoxRows;                /* Number of rows of text in box        */
int    BoxSpacing;                /* Height between font baselines in box    */
int    BoxLowest;                /* Bottom point of box scroll arrow        */
int    BoxBaseline;            /* Baseline of text line 0 in box        */
int    VBorderGap;                /* Aspect-adjusted space betw hrz lines    */
int    LogButtonLeft;            /* Left (X) Position of Logfile button    */
int LogButtonID;            /* Gadget ID of log button on view        */

int    LeftCol;                /* Leftmost displayed column            */
int    RightCol;                /* Rightmost displayed column            */

int DraggingRow;            /* 1 if dragging a row with mouse        */
int SelectRow;                /* Row to draw highlighted                */
int DraggingColumn;            /* 1 if dragging a column with mouse    */
int ClickStartCol;            /* Col pos where mouse first clicked    */
int ClickCurCol;            /* Current column where mouse clicked    */
int SelectStartCol;            /* Start position of selected column    */
int DragOrigColWidth;        /* Starting width of widening column    */
int NextOrigColWidth;        /* Starting width of following column    */
int OrigLeftCol;            /* Starting position of left column        */
int OrigBufWidth;            /* Starting width of buffer                */
int MovedColumn;            /* True if column position was altered    */

EventFormat *DragEvent;        /* Points to column being widened        */
EventFormat *SelectEvent;    /* Points to column being highlighted    */

BPTR   LogFile;                /* Handle of output log file            */
UBYTE *LogBuffer;            /* Buffer for buffered i/o (or NULL)    */
ULONG  LogBufferSize;        /* Size of logfile output buffer        */
ULONG  LogBufferPos;        /* Current position in output buffer    */

UBYTE  MainKeyboard[KB_SHORTCUT_SIZE];    /* For keyboard equivs        */

/*
 *        This table is used to select the appropriate row qualifier
 *        for the row selection mechanism
 */
UWORD RowQualTable[] = {
    0,                /* ROWQUAL_ANY     -- ignore qualifiers                */
    0,                /* ROWQUAL_NONE     -- don't allow any qualifiers        */
    IE_SHIFT,        /* ROWQUAL_SHIFT -- only select if SHIFT is pressed    */
    IE_ALT,            /* ROWQUAL_ALT   -- only select if ALT is pressed    */
    IE_CTRL,        /* ROWQUAL_CTRL     -- only select if CTRL is pressed    */
    IE_ALL            /* ROWQUAL_ALL   -- only select if any qual pressed    */
};

/*
 *        Now our font structures.
 *
 *        We do everything in terms of FontAttr structures, and whenever a
 *        window needs a font, it OpenFont's it itself. This has several
 *        advantages: it allows each window to dynamically select the
 *        best-fitting font, and it also ensures no problems if we have a
 *        window open with one font and the user than changes the font
 *        to something else -- the first window will still have a valid
 *        lock on the old font.
 */
char   BufferLine[MAX_BUFFER_WIDTH];  /* Storage area for buffer lines */

struct TextAttr TopazFontAttr  = {"topaz.font",      8, FS_NORMAL, FPB_ROMFONT };
struct TextAttr SystemFontAttr = {SystemFontName, 0, FS_NORMAL, FPB_DISKFONT};
struct TextAttr WindowFontAttr = {WindowFontName, 0, FS_NORMAL, FPB_DISKFONT};
struct TextAttr BufferFontAttr = {BufferFontName, 0, FS_NORMAL, FPB_DISKFONT};

struct {
    struct TextAttr *gadgetfa;
    struct TextAttr *bufferfa;
} MainWindowFontList[] = {
    &WindowFontAttr,    &BufferFontAttr,
    &SystemFontAttr,    &BufferFontAttr,
    &WindowFontAttr,    &SystemFontAttr,
    &SystemFontAttr,    &SystemFontAttr,
    &TopazFontAttr,        &SystemFontAttr,
    &TopazFontAttr,        &TopazFontAttr,
    NULL,                NULL
};

/*
 *        This is used by the boopsi proportional gadgets
 */
static struct TagItem RZ_MapTags[] = {
    PGA_Top, ICSPECIAL_CODE,
    TAG_END
};

/*
 *        This holds the image pointers for our BOOPSI scroll gadgets
 */
struct Image        *ScrollImage[4];

/*
 *        This structure is used to define our four scroll gadgets. We
 *        define the relative positions of each gadget in terms of the
 *        formula (Scale * Width + offset) or (Scale * Height + offset)
 *        where Width and Height are taken from the image structure.
 */
struct ScrollData {
    int        gadgetid;            /* ID of the gadget                        */
    int        imagetype;            /* Which type of image we're creating    */
    LONG    widthscale;            /* Scale applied to width                */
    LONG    widthoffset;        /* Offset applied to width                 */
    LONG    heightscale;        /* Scale applied to height                */
    LONG    heightoffset;        /* Offset applied to offset                */
    LONG    borderpos;            /* Tag for border containing gadget        */
} ScrollArrows[] = {
    GID_LEFTARROW,    LEFTIMAGE,    -2, -17,    -1, 1,        GA_BottomBorder,
    GID_RIGHTARROW,    RIGHTIMAGE,    -1, -17,    -1, 1,        GA_BottomBorder,
    GID_UPARROW,    UPIMAGE,    -1, 1,        -2, -9,        GA_RightBorder,
    GID_DOWNARROW,    DOWNIMAGE,    -1, 1,        -1, -9,        GA_RightBorder
};

/*
 *        Now the gadgets for the main window
 */
struct MainGadgets {
    UWORD    gadgid;            /* Gadget ID                    */
    UWORD    stringid;        /* ID of label name             */
    UBYTE    col4;            /* Column in 4 x 2 layout        */
    UBYTE    row4;            /* Row in 4 x 2 layout            */
    UBYTE    col6;            /* Column in 4 x 2 layout        */
    UBYTE    row6;            /* Row in 4 x 2 layout            */
    UBYTE    col8;            /* Column in 4 x 2 layout        */
    UBYTE    col12;            /* Column in 12 x 1 layout        */
    UBYTE    widthtype;        /* 0=narrow, 1=wide, 2=status     */
};


struct MainGadgets MainGadgs[] = {
 GID_HIDE,        MSG_HIDE_GAD,          0, 2,     0,    1,    0,    4,    MAIN_NARROW,
 GID_QUIT,        MSG_QUIT_GAD,          1, 2,     1,    1,    1,    5,    MAIN_NARROW,
 GID_PAUSE,        MSG_PAUSE_GAD,          0, 1,     2,    1,    2,    6,    MAIN_NARROW_TOGGLE,
 GID_DISABLE,    MSG_DISABLE_GAD,      1, 1,     3,    1,    3,    7,    MAIN_NARROW_TOGGLE,
 GID_OPENLOG,    MSG_OPENLOG_GAD,    2, 1,     4, 0,    4,    8,  MAIN_WIDE,
 GID_APPENDLOG,    MSG_APPENDLOG_GAD,    2, 1,     4,    0,    4,    8,    MAIN_WIDE_INVIS,
 GID_STARTLOG,    MSG_STARTLOG_GAD,    2, 1,     4,    0,    4,    8,    MAIN_WIDE_INVIS,
 GID_SERIALLOG,    MSG_SERIALLOG_GAD,    2, 1,     4, 0,  4,  8,    MAIN_WIDE_INVIS,
 GID_CLOSELOG,    MSG_CLOSELOG_GAD,    2, 1,     4, 0,    4,    8,  MAIN_WIDE_INVIS,
 GID_SETUP,        MSG_SETUP_GAD,          3, 1,     5,    0,    6,    10,    MAIN_WIDE,
 GID_SAVESET,    MSG_SAVESET_GAD,      2, 2,     4,    1,    5,    9,    MAIN_WIDE,
 GID_FUNCTION,    MSG_FUNCTION_GAD,    3, 2,     5,    1,    7,    11,    MAIN_WIDE,
 GID_STATUS,    MSG_STATUS_GAD,          0, 0,     0,    0,    0,    0,    MAIN_STATUS,
  0, 0, 0, 0, 0, 0, 0, 0, 0
};


/*
 *        Names of gadgets in main window for calculating minimum width
 */
int MainWidthLeftText[] = {
    MSG_PAUSE_GAD,
    MSG_DISABLE_GAD,
    MSG_HIDE_GAD,
    MSG_QUIT_GAD,
    0
};

int MainWidthRightText[] = {
    MSG_OPENLOG_GAD,
    MSG_APPENDLOG_GAD,
    MSG_STARTLOG_GAD,
    MSG_SERIALLOG_GAD,
    MSG_CLOSELOG_GAD,
    MSG_SAVESET_GAD,
    MSG_FUNCTION_GAD,
    MSG_SETUP_GAD,
    0
};


/*
 *        SnoopDos Menus
 *
 *        -- Warning --
 *
 *        If you re-arrange the order of menu items or sub-items, you must
 *        make sure to update the MENU_xxxx #define's at the end to reflect
 *        the new ordering!
 *
 *        (Remember to count bars when working out item numbers, and that
 *        menu/item numbers start from zero, not one.)
 */

#define DIS            NM_ITEMDISABLED
#define TICK        (CHECKIT | MENUTOGGLE)
#define TICKED        (CHECKIT | MENUTOGGLE | CHECKED)
#define BAR            NM_ITEM, NM_BARLABEL, NULL, 0, 0, NULL
#define MENU_END    NM_END,  NULL, NULL, 0,    0, NULL

#define M(type,title_id,flags,mid) \
    type,    (UBYTE *)(title_id), 0, flags, 0, (APTR)(mid)

#define MX(type,title_id,flags,ex,mid) \
    type,    (UBYTE *)(title_id), 0, flags, ex,(APTR)(mid)

struct NewMenu MainMenu[] = {

    /*
     *        Project menu
     */
    M(    NM_TITLE,    MSG_PROJECT_MENU,            0,        0),
    M(   NM_ITEM,   MSG_PROJECT_OPENLOG,        0,        MID_OPENLOG),
    M(     NM_ITEM,    MSG_PROJECT_CLOSELOG,        DIS,    MID_CLOSELOG),
         BAR,
    MX(   NM_ITEM,    MSG_PROJECT_PAUSE,            TICK,   ~8,        MID_PAUSE),
    MX(   NM_ITEM,    MSG_PROJECT_DISABLE,        TICK,   ~16,    MID_DISABLE),
         BAR,
    M(    NM_ITEM,  MSG_PROJECT_STEP,           0,      MID_STEP),
         BAR,
    M(    NM_ITEM,  MSG_PROJECT_PRI,            0,      0),
    MX(    NM_SUB,    MSG_PROJECT_PRI_A,            TICK,   ~1,        MID_CHANGEPRI),
    MX(    NM_SUB,    MSG_PROJECT_PRI_B,            TICK,   ~2,        MID_CHANGEPRI),
    MX(    NM_SUB,    MSG_PROJECT_PRI_C,            TICK,   ~4,        MID_CHANGEPRI),
    MX(    NM_SUB,    MSG_PROJECT_PRI_D,            TICK,   ~8,        MID_CHANGEPRI),
    MX(    NM_SUB,    MSG_PROJECT_PRI_E,            TICK,   ~16,    MID_CHANGEPRI),
    MX(    NM_SUB,    MSG_PROJECT_PRI_F,            TICK,   ~32,    MID_CHANGEPRI),
    MX(    NM_SUB,    MSG_PROJECT_PRI_G,            TICK,   ~64,    MID_CHANGEPRI),
         BAR,
    M(     NM_ITEM,    MSG_PROJECT_HELP,            0,        MID_HELP),
    M(     NM_ITEM,    MSG_PROJECT_ABOUT,            0,        MID_ABOUT),
         BAR,
    M(     NM_ITEM,    MSG_PROJECT_HIDE,            0,        MID_HIDE),
         BAR,
    M(     NM_ITEM,    MSG_PROJECT_QUIT,            0,        MID_QUIT),

    /*
     *        Windows menu
     */
    M(  NM_TITLE,    MSG_WINDOWS_MENU,            0,        0),
    M(   NM_ITEM,    MSG_WINDOWS_SETUP,            0,        MID_SETUP),
    M(   NM_ITEM,    MSG_WINDOWS_FUNCTION,        0,        MID_FUNCTION),
    M(   NM_ITEM,    MSG_WINDOWS_FORMAT,            0,        MID_FORMAT),
         BAR,
    M(   NM_ITEM,   MSG_WINDOWS_WIDTH,            0,      0),
    M(      NM_SUB,    MSG_WINDOWS_WIDTH_1,        0,         MID_SETWIDTH),
    M(      NM_SUB,    MSG_WINDOWS_WIDTH_2,        0,         MID_SETWIDTH),
    M(      NM_SUB,    MSG_WINDOWS_WIDTH_3,        0,         MID_SETWIDTH),
    M(      NM_SUB,    MSG_WINDOWS_WIDTH_4,        0,         MID_SETWIDTH),
    M(      NM_SUB,    MSG_WINDOWS_WIDTH_5,        0,         MID_SETWIDTH),
         BAR,
    M(     NM_ITEM,    MSG_WINDOWS_SPACING,        0,        0),
    MX(      NM_SUB,    MSG_WINDOWS_SPACING_NONE,    TICKED, ~1,    MID_SPACE_NONE),
    MX(      NM_SUB,    MSG_WINDOWS_SPACING_1P,        TICK,   ~2,    MID_SPACE_1P),
    MX(      NM_SUB,    MSG_WINDOWS_SPACING_2P,        TICK,   ~4,    MID_SPACE_2P),

    M(     NM_ITEM,    MSG_WINDOWS_REFRESH,        0,        0),
    MX(   NM_SUB,    MSG_WINDOWS_REF_SIMPLE,        TICK,   ~1, MID_REF_SIMPLE),
    MX(   NM_SUB,    MSG_WINDOWS_REF_SMART,        TICKED, ~2, MID_REF_SMART),

    M(   NM_ITEM,    MSG_WINDOWS_ALIGN,            0,        0),
    MX(      NM_SUB,    MSG_WINDOWS_ALIGN_LEFT,        TICKED, ~1, MID_ALIGN_LEFT),
    MX(      NM_SUB,    MSG_WINDOWS_ALIGN_RIGHT,    TICK,   ~2, MID_ALIGN_RIGHT),

    M(   NM_ITEM,   MSG_WINDOWS_ROW_QUAL,        0,      0),
    MX(      NM_SUB,    MSG_WINDOWS_ROW_ANY,        TICKED,    ~1,  MID_ROWQUAL),
    MX(      NM_SUB,    MSG_WINDOWS_ROW_NONE,        TICK,     ~2,  MID_ROWQUAL),
    MX(      NM_SUB,    MSG_WINDOWS_ROW_SHIFT,        TICK,     ~4,  MID_ROWQUAL),
    MX(      NM_SUB,    MSG_WINDOWS_ROW_ALT,        TICK,     ~8,  MID_ROWQUAL),
    MX(      NM_SUB,    MSG_WINDOWS_ROW_CTRL,        TICK,     ~16, MID_ROWQUAL),
    MX(      NM_SUB,    MSG_WINDOWS_ROW_ALL,        TICK,     ~32, MID_ROWQUAL),

         BAR,
    M(     NM_ITEM,    MSG_WINDOWS_SHOWSTATUS,        TICKED, MID_STATUS),
    M(   NM_ITEM,   MSG_WINDOWS_SHOWGADGETS,    TICKED, MID_GADGETS),
         BAR,
    M(     NM_ITEM,    MSG_WINDOWS_AUTO_OPEN,        TICK,    MID_AUTO_OPEN),
    M(   NM_ITEM,   MSG_WINDOWS_DISABLE_HIDDEN, TICK,   MID_DISABLE_HIDDEN),

    /*
     *        Settings menu
     */
    M(    NM_TITLE,    MSG_SETTINGS_MENU,            0,        0),
    M(     NM_ITEM,    MSG_SETTINGS_LOAD,            0,        MID_LOAD),
    M(     NM_ITEM,    MSG_SETTINGS_SAVE,            0,        MID_SAVE),
    M(     NM_ITEM,    MSG_SETTINGS_SAVEAS,        0,        MID_SAVEAS),
         BAR,
    M(     NM_ITEM,    MSG_SETTINGS_RESETDEFAULTS,    0,        MID_RESET),
    M(     NM_ITEM,    MSG_SETTINGS_LASTSAVED,        0,        MID_LASTSAVED),
    M(     NM_ITEM,    MSG_SETTINGS_RESTORE,        0,        MID_RESTORE),
         BAR,
    M(     NM_ITEM,    MSG_SETTINGS_CREATEICONS,    TICK,   MID_ICONS),

    /*
     *        Buffer menu
     */
    M(    NM_TITLE,    MSG_BUFFER_MENU,            0,        0),
    M(     NM_ITEM,    MSG_BUFFER_COPYWIN,            0,        MID_COPYWIN),
    M(     NM_ITEM,    MSG_BUFFER_COPYBUF,            0,        MID_COPYBUF),
         BAR,
    M(   NM_ITEM,   MSG_BUFFER_SAVEWIN,            0,        MID_SAVEWIN),
    M(     NM_ITEM,    MSG_BUFFER_SAVEBUF,            0,        MID_SAVEBUF),
         BAR,
    M(     NM_ITEM,    MSG_BUFFER_CLEARBUF,        0,        MID_CLEARBUF),

    MENU_END
};

/*
 *        These defines are used when adjusting the menu settings on the fly
 */

#define MENU_OPENLOG        FULLMENUNUM(0,  0, NOSUB)
#define MENU_CLOSELOG        FULLMENUNUM(0,  1, NOSUB)
#define MENU_PAUSE            FULLMENUNUM(0,  3, NOSUB)
#define MENU_DISABLE        FULLMENUNUM(0,  4, NOSUB)
#define MENU_CHANGEPRI        FULLMENUNUM(0,  8, 0)
#define MENU_NUMPRI            7                /* Number of menu priorities */
#define MENU_HIDE            FULLMENUNUM(0,  13, NOSUB)

#define MENU_SPACING0        FULLMENUNUM(1,  6, 0)
#define MENU_SPACING1        FULLMENUNUM(1,  6, 1)
#define MENU_SPACING2        FULLMENUNUM(1,  6, 2)
#define MENU_SIMPLE            FULLMENUNUM(1,  7, 0)
#define MENU_SMART            FULLMENUNUM(1,  7, 1)
#define MENU_AL_LEFT        FULLMENUNUM(1,  8, 0)
#define MENU_AL_RIGHT        FULLMENUNUM(1,  8, 1)
#define MENU_ROWQUAL_ANY    FULLMENUNUM(1,  9, 0)
#define MENU_ROWQUAL_NONE    FULLMENUNUM(1,  9, 1)
#define MENU_ROWQUAL_SHIFT    FULLMENUNUM(1,  9, 2)
#define MENU_ROWQUAL_ALT    FULLMENUNUM(1,  9, 3)
#define MENU_ROWQUAL_CTRL    FULLMENUNUM(1,  9, 4)
#define MENU_ROWQUAL_ALL    FULLMENUNUM(1,  9, 5)
#define MENU_STATUS            FULLMENUNUM(1, 11, NOSUB)
#define MENU_GADGETS        FULLMENUNUM(1, 12, NOSUB)
#define MENU_AUTO_OPEN        FULLMENUNUM(1, 14, NOSUB)
#define MENU_DIS_HIDDEN     FULLMENUNUM(1, 15, NOSUB)

#define MENU_ICONS            FULLMENUNUM(2,  8, NOSUB)

/*****************************************************************************
 *
 *        Start of functions!
 *
 *****************************************************************************/

/*
 *        GetTimeStr(datestamp)
 *
 *        Returns a pointer to a string giving the current time in
 *        hours, mins, and seconds. The string remains valid until
 *        the next time this function is called.
 *
 *        If the datestamp parameter is NULL, then the current date is
 *        used instead.
 */
char *GetTimeStr(struct DateStamp *ds)
{
    static char timestr[20];
    struct DateStamp ourds;
    struct DateTime datetime;

    if (!ds) {
        ds = &ourds;
        DateStamp(ds);
    }
    datetime.dat_Stamp     = *ds;
    datetime.dat_Format     = FORMAT_DOS;
    datetime.dat_Flags     = 0;
    datetime.dat_StrDay     = NULL;
    datetime.dat_StrDate = NULL;
    datetime.dat_StrTime = timestr;
    DateToStr(&datetime);
    return (timestr);
}

/*
 *        UpdateStatus(void)
 *
 *        Determines what the current status is (by examining various
 *        variables) and sets the status line to display an appropriate
 *        message. Call whenever the status may have changed.
 *
 *        Things which can cause a status change: pause/unpause, disable/enable,
 *        open log/close log
 */
void UpdateStatus(void)
{
    if (Paused || Disabled) {
        char *timestr;
        char *merid;
        char *msg;
        int hour;
        int min;

        if (Paused) {
            timestr = GetTimeStr(&PauseDateStamp);
            msg        = MSG(MSG_STATUS_PAUSED);
        } else {
            timestr = GetTimeStr(&DisableDateStamp);
            msg        = MSG(MSG_STATUS_DISABLED);
        }
        hour     = atoi(timestr);
        min      = atoi(timestr+3);
        merid     = "AM";
        if (hour >= 12) {
            hour -= 12;
            merid = "PM";
        }
        mysprintf(StatusLineText, msg, (hour ? hour : 12), min, merid);
    } else if (LogActive) {
        int msgid;

        switch (CurrentLogType) {
            case LT_FILE:            msgid = MSG_STATUS_LOGFILE;        break;
            case LT_DEVICE:            msgid = MSG_STATUS_LOGDEVICE;    break;
            case LT_DEBUG:            msgid = MSG_STATUS_LOGDEBUG;    break;
        }
        mysprintf(StatusLineText, MSG(msgid), CurrentLogName);
    } else
        strcpy(StatusLineText, MSG(MSG_STATUS_NORMAL));

    if (MainWindow) {
        GT_SetGadgetAttrs(Gadget[GID_STATUS], MainWindow, NULL,
                          GTTX_Text, StatusLineText,
                          TAG_DONE);
    }
}

/*
 *        SetLogGadget(logmode, refresh)
 *
 *        Displays the appropriate gadget in the main window according to the
 *        type of logging method chosen. If the logfile is currently open,
 *        the "close log" gadget is displayed, otherwise the correct "open"
 *        gadget is displayed according to the logmode: LOGMODE_PROMPT,
 *        LOGMODE_APPEND, LOGMODE_OVERWRITE, or LOGMODE_SERIALPORT
 *
 *        If the refresh parameter is LG_REFRESH, then refresh gadgets.
 *        LG_NOREFRESH means don't refresh gadgets (i.e. assume we're being
 *        called from the gadget creation routine).
 */
void SetLogGadget(int logmode, int refresh)
{
    static int loggadgets[] = {
        GID_OPENLOG, GID_APPENDLOG, GID_STARTLOG, GID_SERIALLOG,
        GID_CLOSELOG, 0
    };
    int gadid;
    int i;

    if (refresh == LG_REFRESH && !MainWindow)
        return;

    switch (logmode) {
        case LOGMODE_PROMPT:        gadid = GID_OPENLOG;        break;
        case LOGMODE_APPEND:        gadid = GID_APPENDLOG;        break;
        case LOGMODE_SERIALPORT:    gadid = GID_SERIALLOG;        break;
        case LOGMODE_OVERWRITE:        gadid = GID_STARTLOG;        break;
    }
    if (LogActive)
        gadid = GID_CLOSELOG;

    for (i = 0; loggadgets[i]; i++) {
        struct Gadget *gad = Gadget[loggadgets[i]];
        int gadpos;

        if (refresh == LG_REFRESH)
             gadpos = RemoveGadget(MainWindow, gad);

        if (loggadgets[i] == gadid)
            gad->LeftEdge = LogButtonLeft;
        else
            gad->LeftEdge = INVIS_LEFT_EDGE;

        if (refresh == LG_REFRESH) {
            AddGadget(MainWindow, gad, gadpos);
            RefreshGList(gad, MainWindow, NULL, 1);
        }
    }
    LogButtonID = gadid;
}

/*
 *        WriteLog(string)
 *
 *        Writes the specified string to the logfile, handling buffering
 *        etc. as required.
 *
 *        If string is NULL, then flushes any buffers as necessary.
 */
void WriteLog(char *string)
{
    int len;

    if (!LogActive)
        return;

    if (string == NULL) {
        /*
         *        Flush output
         */
        if (LogFile && LogBuffer && LogBufferPos) {
            Write(LogFile, LogBuffer, LogBufferPos);
            LogBufferPos = 0;
        }
        return;
    }

    if (CurrentLogType == LT_DEBUG) {
        /*
         *        Output string to serial terminal, expanding LF's to CR/LF's
         *        as we go.
         */
        while (*string) {
            if (*string == '\n')
                RawPutChar('\r');
            RawPutChar(*string++);
        }
        return;
    }
    len = strlen(string);
    if (LogBuffer) {
        /*
         *        Buffered i/o so add string to buffer; if necessary, flush
         *        buffer first.
         */
        if ((LogBufferPos + len) > LogBufferSize) {
            Write(LogFile, LogBuffer, LogBufferPos);
            LogBufferPos = 0;
        }
        memcpy(LogBuffer + LogBufferPos, string, len);
        LogBufferPos += len;
    } else {
        /*
         *        Plain unbuffered i/o
         */
        Write(LogFile, string, strlen(string));
    }
}

/*
 *        CloseLog()
 *
 *        Closes the currently open logfile (if any)
 */
void CloseLog(void)
{
    char msg[100];

    if (!LogActive)
        return;

    mysprintf(msg, MSG(MSG_LOG_STOP), GetTimeStr(NULL));
    WriteLog(msg);
    WriteLog(NULL);    /* Flush output */
    LogActive = 0;
    SetLogGadget(DefaultLogMode, LG_REFRESH);
    UpdateStatus();
    SetMenuOptions();
    if (LogFile) {
        int oldpaused = Paused;

        Paused = 0;
        Close(LogFile);
        LogFile = NULL;
        Paused = oldpaused;
    }
    if (LogBuffer) {
        FreeMem(LogBuffer, LogBufferSize);
        LogBuffer = NULL;
    }
}

/*
 *        WriteLogHeader()
 *
 *        Writes the standard SnoopDos header line to the logfile using the
 *        current logfile format
 */
void WriteLogHeader(void)
{
    FormatEvent(LogEFormat, NULL, BufferLine+1, 0, LogWidth - 1);
    BufferLine[0]           = ' ';
    BufferLine[LogWidth+1] = '\n';
    BufferLine[LogWidth+2] = 0;
    WriteLog(BufferLine);
    UnderlineTitles(LogEFormat, BufferLine+1, '-');
    BufferLine[LogWidth+1] = '\n';
    WriteLog(BufferLine);
}

/*
 *        OpenLog(mode, filename)
 *
 *        Opens the named file for logging. If a log file is already open,
 *        then closes the existing file first.
 *
 *        Mode is set to:
 *
 *            LOGMODE_PROMPT       - Prompt user if file exits for append/overwrite
 *            LOGMODE_APPEND       - Automatically append to file if it exists
 *            LOGMODE_OVERWRITE  - Automatically overwrite file it if exitsts
 *            LOGMODE_SERIALPORT - Direct output to debugger on serial port
 *
 *        Filename is ignored if mode is set to LOGMODE_SERIALPORT.
 *
 *        Returns 1 for success, 0 for failure (couldn't open file?)
 */
int OpenLog(int logmode, char *filename)
{
    APTR oldwinptr = *TaskWindowPtr;
    char startmsg[100];
    char timestr[20];
    char datestr[20];
    char weekday[20];
    struct DateTime datetime;
    int pausestate = Paused;

    Paused = 0;
    if (LogActive)
        CloseLog();

    if (logmode == LOGMODE_SERIALPORT) {
        CurrentLogType = LT_DEBUG;
    } else {
        int filemode;
        int buffer = 0;

        strcpy(CurrentLogName, filename);
        *TaskWindowPtr = (APTR)-1;
        if (IsFileSystem(filename))
            CurrentLogType = LT_FILE;
        else
            CurrentLogType = LT_DEVICE;
        *TaskWindowPtr = oldwinptr;

        if (logmode == LOGMODE_PROMPT && CurrentLogType == LT_FILE) {
            BPTR lock = Lock(filename, ACCESS_READ);

            if (lock) {
                UnLock(lock);
                switch (GetResponse(MSG(MSG_REQ_APPEND_OVERWRITE_CANCEL),
                                    MSG(MSG_REQ_FILE_EXISTS), filename)) {

                    case 1:        filemode = MODE_READWRITE;        break;
                    case 2:        filemode = MODE_NEWFILE;        break;
                    default:    goto open_okay;
                }
            } else
                filemode = MODE_NEWFILE;
        } else if (logmode == LOGMODE_APPEND)
            filemode = MODE_READWRITE;
        else
            filemode = MODE_NEWFILE;

        LogFile = Open(filename, filemode);
        if (!LogFile)
            goto open_failed;

        if (filemode == MODE_READWRITE) {
            Seek(LogFile, 0, OFFSET_END);
            Write(LogFile, "\n", 1); /* Leave space between multiple logs */
        }

        /*
         *        Now select buffer type for file according to gadget and
         *        file type.
         */
        switch (CurSettings.Setup.FileIOType) {
            case FILE_AUTOMATIC:
                if (CurrentLogType == LT_FILE)
                    buffer = 1;
                break;

            case FILE_IMMEDIATE:        buffer = 0;    break;
            case FILE_BUFFERED:            buffer = 1; break;
        }
        if (buffer) {
            /*
             *        Allocate a buffer for file i/o. Doesn't matter if
             *        it fails -- we just drop back to unbuffered file
             *        i/o instead.
             */
            LogBufferSize = LOGBUFFER_SIZE;
            LogBufferPos  = 0;
            LogBuffer     = AllocMem(LogBufferSize, MEMF_ANY);
        }
    }
    LogActive = 1;
    SetLogGadget(DefaultLogMode, LG_REFRESH);
    UpdateStatus();
    SetMenuOptions();

    DateStamp(&datetime.dat_Stamp);
    datetime.dat_Format     = FORMAT_DOS;
    datetime.dat_Flags     = 0;
    datetime.dat_StrDay     = weekday;
    datetime.dat_StrDate = datestr;
    datetime.dat_StrTime = timestr;
    DateToStr(&datetime);
    mysprintf(startmsg, MSG(MSG_LOG_START), weekday, datestr, timestr);

    /*
     *        Now select appropriate output format for log
     */
    LogWidth = ParseFormatString(LogFormat, LogEFormat, MAX_FORM_LEN);
    if (!LogWidth)
        LogWidth = ParseFormatString(BufFormat, LogEFormat, MAX_FORM_LEN);
    WriteLog(startmsg);
    WriteLogHeader();
open_okay:
    Paused = pausestate;
    return (1);

open_failed:
    Paused = pausestate;
    return (0);
}

/*
 *        SaveBuffer(savetype, savename, overwrite)
 *
 *        This function saves the contents of some or all of the current
 *        buffer to a disk file or to the clipboard.
 *
 *        savetype is SAVEBUF_WINDOW to save only that portion of the
 *        buffer that is currently displayed in the main window, or
 *        SAVEBUF_ALL to save the entire buffer.
 *
 *        savename is a pointer to a disk filename, or SAVEBUF_CLIPBOARD to
 *        save to the clipboard.device.
 *
 *        overwrite is SAVEBUF_OVERWRITE to force an existing file to be
 *        overwritten automatically or SAVEBUF_PROMPT to let the user
 *        choose whether to overwrite using a requester. If the user
 *        chooses not to overwrite, then success is returned.
 *
 *        Returns 1 for success or 0 for failure.
 */
int SaveBuffer(int savetype, char *savename, int overwrite)
{
    struct IOClipReq *clipreq;
    struct MsgPort     *clipport;
    BPTR  savefile;
    UBYTE *savebuf;
    Event *curev;
    ULONG curpos;
    int startseq;
    int curseq;
    int endseq;
    int leftcol;
    int rightcol;
    int totalsize;
    int width;
    int numlines;

    if (savetype == SAVEBUF_WINDOW) {
        /*
         *        Save only visible portion of buffer
         */
        startseq    = TopSeq;
        curev        = TopEvent;
        endseq        = BottomSeq;
        leftcol        = LeftCol;
        rightcol    = RightCol;
    } else {
        /*
         *        Save entire buffer
         */
        startseq    = RealFirstSeq;
        curev        = HeadNode(&EventList);
        endseq        = EndSeq;
        leftcol        = 0;
        rightcol    = BufferWidth - 1;
    }

    savebuf = AllocMem(SAVEBUFFER_SIZE, MEMF_ANY);
    if (!savebuf)
        return (0);

    curpos = 0;

    /*
     *        Now try and open our output device
     */
    if (savename == SAVEBUF_CLIPBOARD) {
        /*
         *        Open clipboard
         */
        clipport = CreateMsgPort();
        if (!clipport) {
            FreeMem(savebuf, SAVEBUFFER_SIZE);
            return (0);
        }
        clipreq = (struct IOClipReq *)CreateExtIO(clipport, sizeof(*clipreq));
        if (!clipreq) {
            FreeMem(savebuf, SAVEBUFFER_SIZE);
            DeleteMsgPort(clipport);
            return (0);
        }
        if (OpenDevice("clipboard.device", 0, (void *)clipreq, 0)) {
            FreeMem(savebuf, SAVEBUFFER_SIZE);
            DeleteExtIO((struct IORequest *)clipreq);
            DeleteMsgPort(clipport);
            return (0);
        }
        clipreq->io_Error    = 0;
        clipreq->io_Offset    = 0;
        clipreq->io_ClipID    = 0;
    } else {
        /*
         *        Open log file
         */
        int filemode = MODE_NEWFILE;;

        if (overwrite == SAVEBUF_PROMPT) {
            BPTR lk = Lock(savename, ACCESS_READ);

            if (lk) {
                UnLock(lk);
                switch (GetResponse(MSG(MSG_REQ_APPEND_OVERWRITE_CANCEL),
                                    MSG(MSG_REQ_FILE_EXISTS), savename)) {

                    case 1:        filemode = MODE_READWRITE;        break;
                    case 2:        filemode = MODE_NEWFILE;        break;
                    default:    FreeMem(savebuf, SAVEBUFFER_SIZE);
                                return (1);
                }
            }
        }
        savefile = Open(savename, filemode);
        if (!savefile) {
            FreeMem(savebuf, SAVEBUFFER_SIZE);
            return (0);
        }
        if (filemode == MODE_READWRITE) {
            Seek(savefile, 0, OFFSET_END);
            Write(savefile, "\n", 1);    /* Leave blank line between appends */
        }
    }

    /*
     *        Now calculate how many lines there are to be saved in the
     *        buffer. There will be as many lines as were selected from
     *        startseq to endseq (inclusive) plus two additional lines for
     *        the header and underline. Each line will have (rightcol-leftcol+1)
     *        characters on it, plus one additional character for the newline.
     *        We need to calculate all this in advance because the header
     *        written for the clipboard includes the number of characters of
     *        text to be written.
     */
    width = (rightcol - leftcol + 1);

    if (IsListEmpty(&EventList))
        numlines = 2;
    else
        numlines = (endseq - startseq + 1) + 2;

    totalsize = (width + 1) * numlines;

    if (savename == SAVEBUF_CLIPBOARD) {
        /*
         *        Write the clipboard FTXT header into the buffer. We
         *        need to write the amount of text, but we also need
         *        to write the total size of the clip (including header)
         *        rounded to a word boundary.
         */
        int cliplen = (totalsize + 13) & ~1;    /* Includes header */

        memcpy(savebuf, "FORM....FTXTCHRS....", 20);
        *((ULONG *)&savebuf[4])  = cliplen;
        *((ULONG *)&savebuf[16]) = totalsize;
        curpos += 20;
    }
    /*
     *        Next, output the two header lines (the column headings plus
     *        the underline)
     */
    FormatEvent(BufferEFormat, NULL, savebuf + curpos, leftcol, rightcol);
    curpos += width;
    savebuf[curpos++] = '\n';

    UnderlineTitles(BufferEFormat, BufferLine, '-');
    memcpy(savebuf + curpos, BufferLine + leftcol, width);
    curpos += width;
    savebuf[curpos++] = '\n';

    /*
     *        Now walk through the lines in the buffer, outputting each line
     *        one at a time.
     */
    curseq     = startseq;
    totalsize -= (width + width + 2);    /* Allow for header */

    while (totalsize > 0) {
        /*
         *        First check if we have enough room in the buffer for
         *        the next line -- if not, then flush the buffer
         */
        if ((curpos + width + 2) >= SAVEBUFFER_SIZE) {
            if (savename == SAVEBUF_CLIPBOARD) {
                clipreq->io_Command = CMD_WRITE;
                clipreq->io_Data    = savebuf;
                clipreq->io_Length    = curpos;
                DoIO((struct IORequest *)clipreq);
            } else
                Write(savefile, savebuf, curpos);
            curpos = 0;
        }
        /*
         *        The next section must be completely enclosed in
         *        ObtainSemaphore/ReleaseSemaphore to ensure the
         *        buffer doesn't change under our feet
         */
        ObtainSemaphore(&BufSem);
        if (curseq < RealFirstSeq) {
            /*
             *        Uhoh -- the list has scrolled past us while we
             *        were outputting it; catch up as best we can.
             */
            curev = HeadNode(&EventList);
            if (NextNode(curev))
                 curseq = curev->seqnum;
            else
                 curseq = endseq + 1;
        }
        if (curseq > endseq) {
            /*
             *        We've somehow run out of lines -- this should never
             *        happen, but you never know. For disk files, we can
             *        just avoid outputting anything else. For the
             *        clipboard, we need to output something, so we just
             *        output a line of spaces.
             */
            if (savename != SAVEBUF_CLIPBOARD)
                break;
            memset(savebuf + curpos, ' ', width);
        } else {
            FormatEvent(BufferEFormat, curev, savebuf + curpos,
                        leftcol, rightcol);
            curev = NextNode(curev);
            curseq++;
        }
        curpos += width;
        savebuf[curpos++] = '\n';
        totalsize -= (width + 1);
        ReleaseSemaphore(&BufSem);
    }

    /*
     *        Now we've output the entire save region, so just flush anything
     *        left in the save buffer and we're done.
     */
    if (savename == SAVEBUF_CLIPBOARD) {
        /*
         *        Make sure out total output is word-aligned, otherwise
         *        Bad Things will happen
         */
        if (totalsize & 1)
            savebuf[curpos++] = '\0';

        if (curpos > 0) {
            clipreq->io_Command = CMD_WRITE;
            clipreq->io_Data    = savebuf;
            clipreq->io_Length    = curpos;
            DoIO((struct IORequest *)clipreq);
        }
        clipreq->io_Command = CMD_UPDATE;
        DoIO((struct IORequest *)clipreq); /* Make data publically available */

        CloseDevice((struct IORequest *)clipreq);
        DeleteExtIO((struct IORequest *)clipreq);
        DeleteMsgPort(clipport);
    } else {
        if (curpos)
            Write(savefile, savebuf, curpos);
        Close(savefile);
    }
    FreeMem(savebuf, SAVEBUFFER_SIZE);
    return (1);
}

/*
 *        SetMonitorMode(type)
 *
 *        Sets the current monitor mode to the specified type. This will
 *        be one of the following three:
 *
 *            MONITOR_NORMAL
 *            MONITOR_PAUSED
 *            MONITOR_DISABLED
 *
 *        Automatically takes care of updating the gadget imagery and
 *        menu options to reflect the mode. Also ignores attempts to
 *        Pause() if the main window isn't currently open. Note that
 *        the three modes are mutually exclusive.
 *
 *        The status line is also updated to reflect the current mode.
 *        The global MonitorType reflects the currently selected mode
 *        after this call.
 *
 *        Important: any call which may possible spawn a subtask
 *        (e.g. showing an ASL file requester etc.) must force the Paused
 *        variable to 0 before hand and then restore it to its original
 *        setting afterwards. This ensures that any other tasks that were
 *        already paused remain paused, but any new tasks that make calls
 *        during the activity will not be paused.
 *
 *        This isn't perfect, but it gives about 99% certainty of avoiding
 *        deadlocks, while still ensuring that any existing paused tasks
 *        (normally just one or two) remain paused. Thus, if someone has
 *        paused some stuff so they can open a log file, turn on the
 *        printer, or whatever, it will remain paused. (The possibility of
 *        deadlock comes about if our external file i/o somehow causes
 *        another process to make a call to one of the monitored SnoopDos
 *        functions, e.g. OpenLibrary or OpenDevice).
 *
 *        The alternative is to completely disable pausing on such calls, in
 *        which case vast quantities of output might be generated while the
 *        person is messing around in the file requester oblivious.
 *
 *        NOTE: It is impossible to enter PAUSED mode unless the SnoopDos
 *        window is open -- this is to prevent situations where you freeze
 *        the system (e.g. it's waiting for you to unpause, but you can't
 *        because you can't call up the main window due to something else.)
 */
void SetMonitorMode(int modetype)
{
    int paused   = 0;
    int disabled = 0;
    int changed  = 0;

    if (!MainWindow && modetype == MONITOR_PAUSED)
        return;

    if (modetype == MONITOR_DISABLED)
        disabled = 1;
    else if (modetype == MONITOR_PAUSED)
        paused = 1;

    /*
     *        Now update main window gadgets if necessary
     */
    if (MainWindow) {
        if (paused != Paused) {
            ShowGadget(MainWindow, Gadget[GID_PAUSE],
                       (paused ? GADGET_DOWN : GADGET_UP));
        }
        if (disabled != Disabled) {
            ShowGadget(MainWindow, Gadget[GID_DISABLE],
                       (disabled ? GADGET_DOWN : GADGET_UP));
        }
    }

    /*
     *        Next,  make the changes actually take effect.
     */
    if (paused != Paused) {
        DateStamp(&PauseDateStamp);
        if (paused)
            ObtainSemaphore(&PauseSem);
        else
            ReleaseSemaphore(&PauseSem);
        Paused  = paused;
        changed = 1;
    }
    if (disabled != Disabled) {
        DateStamp(&DisableDateStamp);
        Disabled = disabled;
        changed  = 1;
        LoadFuncSettings(&CurSettings.Func);    /* Update patches state */

        if (LogActive) {
            char msg[100];

            mysprintf(msg, MSG(Disabled ? MSG_LOG_DISABLED : MSG_LOG_ENABLED),
                           GetTimeStr(NULL));
            WriteLog(msg);
            WriteLog(NULL);    /* Flush output to keep everything up-to-date */
        }
    }
    if (changed) {
        if (LogActive)        /* Flush log file when Paused */
            WriteLog(NULL);
        UpdateStatus();
        SetMenuOptions();
    }
    MonitorType = modetype;
}

/*
 *        SingleStep()
 *
 *        Undoes Pause just long enough for all currently waiting tasks
 *        to execute a single monitored event. Usually, this will just
 *        produce a single event in the event buffer.
 *
 *        Why would you want to do this? Because it's a real handy way
 *        of single-stepping through a program's actions at startup,
 *        especially if it happens to be crashing after doing a particular
 *        action!
 *
 *        We implement the singlestep by freeing up the Pause semaphore
 *        and then immediately trying to recapture it. We rely on the
 *        fact that Exec schedules semaphore operations on a strictly
 *        first-come first-served basis, so as soon as we free it,
 *        all the waiting tasks are guaranteed to run before we can
 *        recapture it. We move ourselves to a high priority temporarily
 *        to ensure that nobody gets a chance to run two events before
 *        we can regain control again.
 *
 *        If we weren't in pause mode before, we will be when we exit.
 *
 */
void SingleStep(void)
{
    int oldpri;

    if (!MainWindow)
        return;

    if (!Paused)
        SetMonitorMode(MONITOR_PAUSED);

    WriteLog(NULL);        /* Make sure logfile is up to date! */

    /*
     *        To ensure that we get the semaphore back as soon as we
     *        possibly can (i.e. let all the waiting tasks run but nobody
     *        else), we bump our priority up temporarily
     */
    oldpri = SetTaskPri(SysBase->ThisTask, 25);
    ReleaseSemaphore(&PauseSem);
    ObtainSemaphore(&PauseSem);
    SetTaskPri(SysBase->ThisTask, oldpri);
}

/*
 *        CheckForScreen()
 *
 *        Checks if we've already got a SnoopDos screen open -- if we do,
 *        then returns TRUE. If we don't, then tries to lock the current
 *        screen and returns TRUE. If we can't lock the screen, then
 *        displays an error message and returns FALSe.
 */
int CheckForScreen(void)
{
    if (!SnoopScreen) {
        SetupScreen();
        if (!SnoopScreen) {
            ShowError(MSG(MSG_ERROR_NO_SCREEN));
            return (FALSE);
        }
    }
    return (TRUE);
}

/*
 *        ShowSnoopDos()
 *
 *        Attempts to open SnoopDos on the user's current preferred screen.
 *        If SnoopDos is already running, but on a different screen, then
 *        it is moved to this screen. Any open SnoopDos windows are moved,
 *        though any AmigaGuide help remains on the previous screen until
 *        the next time help is requested.
 *
 *        Fails if we can't lock the new screen for some reason (this
 *        should never happen!)
 */
int ShowSnoopDos(void)
{
    struct Screen *prevscr  = SnoopScreen;
    struct Window *prevfunc = FuncWindow;
    struct Window *prevform = FormWindow;
    struct Window *prevset  = SetWindow;

    if (!SetupScreen()) {
        ShowError(MSG(MSG_ERROR_NO_SCREEN));
        return (FALSE);
    }
    RemoveProgramFromWorkbench();
    ScreenToFront(SnoopScreen);
    if (prevscr == SnoopScreen) {
        /*
         *        We were already running, and we're on the
         *        same screen, so nothing else to do. For good
         *        measure, we bring the main window to the
         *        foreground, however.
         */
        OpenMainWindow();
        return (TRUE);
    }
    if (prevscr != NULL) {
        /*
         *        We're moving from a previous screen to this new screen,
         *        so bring all the windows with us
         */
        CleanupSubWindows();
        CloseMainWindow();
        OpenMainWindow();
        if (prevset)    OpenSettingsWindow();
        if (prevfunc)    OpenFunctionWindow();
        if (prevform)    OpenFormatWindow();
    } else {
        /*
         *        We're opening on an entirely new screen -- if
         *        DisableOnHide is true, then we need to restore
         *        the saved state of Disable/Enable (since it will
         *        have been disabled while in the background)
         */
        if (DisableOnHide)
            SetMonitorMode(LastKnownState);
        OpenMainWindow();
    }
    return (TRUE);
}

/*
 *        HideSnoopDos()
 *
 *        Removes all SnoopDos windows from the screen. If DisableOnHide
 *        is true, then SnoopDos is put into a disabled state. Otherwise,
 *        if we're currently paused, then SnoopDos is unpaused (since
 *        otherwise, it would be easy to get into a situation where
 *        everything was frozen and you could do nothing to bring
 *        SnoopDos back to life).
 *
 *        If commodities library hasn't been opened, then we don't hide
 *        since that would make it difficult to resurrect SnoopDos again.
 *        However, if commodities library is open but the user has given
 *        an invalid hotkey, we do hide -- they can always use commodities
 *        exchange to reactivate it.
 */
void HideSnoopDos(void)
{
    LastKnownState = MonitorType;

    if (CurSettings.Setup.HideMethod == HIDE_NONE)
        return;

    CleanupSubWindows();
    CloseMainWindow();
    CleanupScreen();
    if (DisableOnHide)
        SetMonitorMode(MONITOR_DISABLED);
    else if (Paused)
        SetMonitorMode(MONITOR_NORMAL);
    if (CurSettings.Setup.HideMethod != HIDE_INVIS)
        AddProgramToWorkbench(CurSettings.Setup.HideMethod);
}

/*
 *        InitMenus()
 *
 *        Should be called once as soon as the language file has been
 *        read in. Walks down the menu structure and replaces the
 *        message ID's with actual pointers to the message.
 */
void InitMenus(void)
{
    struct NewMenu *menu;

    for (menu = &MainMenu[0]; menu->nm_Type != NM_END; menu++) {
        if (menu->nm_Label && menu->nm_Label != NM_BARLABEL) {
            char *msg = MSG((ULONG)(menu->nm_Label));

            menu->nm_Label = msg + 2;
            if (*msg && *msg != ' ')
                menu->nm_CommKey = msg;
        }
    }
}

/*
 *        CalcMinMainSize(gadgetfa, bufferfa, &width, &height)
 *
 *        Fills in width and height with the minimum allowable dimensions
 *        the main window can obtain using the specified gadget and buffer
 *        fonts. Returns TRUE for success, FALSE for failure (e.g. window
 *        to big to fit on screen using current fonts).
 */
BOOL CalcMinMainSize(struct TextAttr *gadgetfa, struct TextAttr *bufferfa,
                     int *pwidth, int *pheight)
{
    struct TextFont *gfont;
    struct TextFont *bfont;
    int widthleft;
    int widthright;
    int width;
    int height;
    int fonty;
    int bfonty;
    int bfontx;
    int bordright = SizeImage->Width;
    int bordbot   = SizeImage->Height;

    gfont = MyOpenFont(gadgetfa);
    if (!gfont)
        return (FALSE);

    bfont = MyOpenFont(bufferfa);
    if (!bfont) {
        CloseFont(gfont);
        return (FALSE);
    }
    if (bfont->tf_Flags & FPF_PROPORTIONAL) {
        CloseFont(bfont);
        CloseFont(gfont);
        return (FALSE);
    }
    fonty        = gfont->tf_YSize;
    bfonty        = bfont->tf_YSize;
    bfontx      = bfont->tf_XSize;

    widthleft   = MaxTextLen(gfont, MainWidthLeftText)  + 12;
    widthright  = MaxTextLen(gfont, MainWidthRightText) + 12;

    width  = (widthleft + widthright + MAIN_MARGIN) * 2 +
             BorderLeft + bordright;
    height = TitlebarHeight + (bfonty + BoxInterGap) * 3 +
             bordbot + 20 + (fonty + 10) * 3;

    CloseFont(bfont);
    CloseFont(gfont);

    if (width > ScreenWidth || height > ScreenHeight)
        return (FALSE);

    *pwidth  = width;
    *pheight = height;
    return (TRUE);
}

/*
 *        SetupBufferRastPort()
 *
 *        Sets up the main window rastport to have the correct font and
 *        colours for rendering. Should always be called before OutputBufLine
 *        if gadget operations may have occurred since the last redraw.
 */
void SetupBufferRastPort(void)
{
    struct RastPort *rport = MainWindow->RPort;

    SetAPen(rport, 1);
    SetBPen(rport, 0);
    SetDrMd(rport, JAM2);
    SetFont(rport, BufferFont);
}

/*
 *        DrawHeaderLine()
 *
 *        Redraws the current event header line in the top part of the window
 *
 *        If a column is currently selected for dragging, then draws the
 *        column heading in white to indicate it's active.
 */
void DrawHeaderLine(void)
{
    struct RastPort *rport = MainWindow->RPort;
    int numcols = RightCol - LeftCol + 1;

    if (ClearMainRHS)
        numcols = BoxCols;

    SetupBufferRastPort();
    FormatEvent(BufferEFormat, NULL, BufferLine, LeftCol, LeftCol+numcols-1);

    /*
     *        We mark the very last position on the header line with a single
     *        dot, which can then be grabbed by the user to resize the width
     *        of the last column. We don't overwrite the actual text of the
     *        final header, if it's narrow.
     *
     *        If the columns are currently being dragged, we display a | instead
     *        of a dot, to make it easier to spot, and we display it even if
     *        it would overwrite some of the final heading.
     */
    if (DraggingColumn) {
        /*
         *        Draw the currently selected column with a white heading,
         *        and the other stuff with a black heading
         */
        int selectwidth = SelectEvent->width;

        if ((SelectEvent+1)->type != EF_END) {
            /*
             *        If we're not highlighting the last column already
             *        then indicate the end of the last column with a
             *        little vertical bar
             */
            BufferLine[BufferWidth - LeftCol - 1] = '|';
        }
        if (SelectStartCol > LeftCol) {
            /*
             *        Draw black portion to left of selected column
             */
            int width = MIN(SelectStartCol - LeftCol, numcols);

            Move(rport, BoxInLeft, BoxHeaderLine);
            Text(rport, BufferLine, width);
        }
        if ((SelectStartCol + selectwidth) < (LeftCol + numcols)) {
            /*
             *        Draw black portion to right of selected column
             */
            int xoffset = SelectStartCol + selectwidth - LeftCol;

            if (xoffset < 0)
                xoffset = 0;

            Move(rport, BoxInLeft + BoxCharWidth * xoffset, BoxHeaderLine);
            Text(rport, BufferLine + xoffset, numcols - MAX(xoffset,0));
        }
        if (SelectStartCol >= LeftCol && SelectStartCol < (LeftCol+numcols)) {
            /*
             *        Draw selected column heading in white
             */
            int xoffset = SelectStartCol - LeftCol;
            int fwidth  = MIN(selectwidth, numcols - xoffset);

            if (fwidth > 0) {
                SetAPen(rport, 2);
                Move(rport, BoxInLeft  + xoffset * BoxCharWidth,
                     BoxHeaderLine);
                Text(rport, BufferLine + xoffset, fwidth);
                SetAPen(rport, 1);
            }
        } else if (SelectStartCol < LeftCol &&
                   (SelectStartCol + selectwidth) >= LeftCol) {
            /*
             *        Draw portion of selected column heading in white
             */
            int colwidth = SelectStartCol + selectwidth - LeftCol;

            SetAPen(rport, 2);
            Move(rport, BoxInLeft, BoxHeaderLine);
            Text(rport, BufferLine, MIN(colwidth, numcols));
            SetAPen(rport, 1);
        }
    } else {
        /*
         *        Not dragging a column, so draw entire line in black
         */
        Move(rport, BoxInLeft, BoxHeaderLine);
        Text(rport, BufferLine, numcols);
    }
}

/*
 *        RedrawMainWindow()
 *
 *        Redraws all the main parts of the window, except gadgets.
 */
void RedrawMainWindow(void)
{
    struct RastPort *rport;

    if (!MainWindow)
        return;

    rport = MainWindow->RPort;
    DrawBevelBox(rport, BoxLeft, MainWindow->BorderTop,
                        BoxWidth, BoxTop - MainWindow->BorderTop,
                        GT_VisualInfo,    MainVI,
                        TAG_DONE);
    DrawBevelBox(rport, BoxLeft, BoxTop, BoxWidth, BoxHeight,
                        GT_VisualInfo,    MainVI,
                        TAG_DONE);
    /*
     *        We only draw the third bevel box if either the status line or
     *        gadget line is enabled.
     */
    if (StatusLine || GadgetsLine) {
        DrawBevelBox(rport, BoxLeft, BoxTop + BoxHeight, BoxWidth,
                            MainWindow->Height - MainWindow->BorderBottom -
                                                 BoxTop - BoxHeight,
                            GT_VisualInfo,    MainVI,
                            TAG_DONE);
    }
    DrawHeaderLine();
    ShowBuffer(TopSeq, DISPLAY_ALL);
    if (ClearMainRHS) {
        if ((RightCol-LeftCol+1) < BoxCols) {
            /*
             *        Erase strip to right of our rendered text
             */
            SetAPen(rport, 0);
            SetDrMd(rport, JAM1);
            RectFill(rport, BoxInLeft + (RightCol-LeftCol+1) * BoxCharWidth,
                            BoxInTop,
                            BoxInLeft + BoxInWidth - 1,
                            BoxInTop + BoxInHeight - 1);
        }
        ClearMainRHS = 0;
    }
}

/*
 *        SetTextSpacing(newspacing)
 *
 *        Updates the spacing of the main window to reflect the new spacing
 *        value passed in, and adjust all the global variables accordingly.
 */
void SetTextSpacing(int newspacing)
{
    int bfonty          = BufferFont->tf_YSize;
    int bfontbaseline = BufferFont->tf_Baseline;
    int maxheight;

    if (BoxInterGap == newspacing)
        return;        /* No change needed */

    ChangedSpacing = 1;            /* Flag for resize routine */
    BoxInterGap    = newspacing;

    if (!MainWindow)
        return;

    SetAPen(MainWindow->RPort, 0);
    SetDrMd(MainWindow->RPort, JAM1);
    RectFill(MainWindow->RPort, BoxInLeft, BoxInTop,
                                BoxInLeft + BoxInWidth - 1,
                                BoxInTop + BoxInHeight - 1);

    maxheight    = BoxHeight - VBorderGap * 2 - 2;
    BoxSpacing    = bfonty + BoxInterGap;
    BoxRows        = (maxheight + BoxInterGap) / BoxSpacing;
    BoxInHeight    = BoxRows * BoxSpacing - BoxInterGap;
    BoxInTop    = BoxTop   + VBorderGap + 1;
    BoxBaseline    = BoxInTop + bfontbaseline;

    /*
     *        We now check to see if we're currently at the end of the buffer,
     *        and if so, make sure we stay that way by repositioning after the
     *        line change.
     */
    if (BottomSeq >= EndSeq)
        ShowBuffer(EndSeq, DISPLAY_NONE);

    LOCK_LAYERS;
    RedrawMainWindow();
    UNLOCK_LAYERS;
    UpdateMainVScroll();
}

/*
 *        InitMainMargins()
 *
 *        Initialises the window margins according to the currently selected
 *        left offset and the current buffer width (as determined by the
 *        format string). Automatically ensures margins are kept within
 *        the bounds of the displayable area, adjusting them as necessary.
 *
 *        On entry, LeftCol should contain the current left margin, BoxCols
 *        should be initialised to the current width of the displayable
 *        buffer area, and BufferWidth should be the maximum width of the
 *        currently selected format string.
 */
void InitMainMargins(void)
{
    if ((LeftCol + BoxCols) > BufferWidth)
        LeftCol = BufferWidth - BoxCols;

    if (LeftCol < 0)
        LeftCol = 0;

    RightCol = LeftCol + BoxCols - 1;
    if (RightCol >= BufferWidth) {
        RightCol = BufferWidth - 1;
        if (RightCol < 0)
            RightCol = 0;
    }
}

/*
 *        FreeScrollGadgets()
 *
 *        Frees all associated BOOPSI objects and images used by the
 *        scroll gadgets. Must only be called after the main window
 *        has closed.
 */
void FreeScrollGadgets(void)
{
    int i;

    for (i = GID_STARTSCROLL; i <= GID_ENDSCROLL; i++) {
        if (Gadget[i]) {
            DisposeObject(Gadget[i]);
            Gadget[i] = NULL;
        }
    }
    for (i = 0; i < 4; i++) {
        if (ScrollImage[i]) {
            DisposeObject(ScrollImage[i]);
            ScrollImage[i] = NULL;
        }
    }
}

/*
 *        FreeMainGadgets()
 *
 *        Frees all the gadgets allocated for the main window.
 */
void FreeMainGadgets(void)
{
    if (BufferFont) {
        CloseFont(BufferFont);
        BufferFont  = NULL;
    }
    if (MainGadList) {
        FreeGadgets(MainGadList);
        MainGadList = NULL;
    }
}

/*
 *        CreateScrollGadgets()
 *
 *        Creates the list of six gadgets that are used to give our window
 *        scroll bars and scroll arrows. These have to be created independently
 *        of the GadTools button gadgets, because since they are in the border,
 *        they must be added to the window at the time it is opened, and not
 *        afterwards.
 *
 *        The GadTools gadgets are removed and then re-added (with new
 *        size-sensitive positions) whenever the window is resized; if we
 *        try and do this with the BOOPSI border gadgets however, Intuition
 *        gets the positioning subtely wrong the second and subsequent times.
 *
 *        Hence you must call this function before opening the main window. All
 *        the gadgets are created relative to the current window dimensions, and
 *        so do not depend on specific hardcoded with/height values.
 *
 *        Returns a pointer to the gadget list, or NULL if the gadgets
 *        couldn't be created.
 */
struct Gadget *CreateScrollGadgets(void)
{
    struct Gadget *gadlist    = NULL;
    struct Gadget *gad        = (struct Gadget *)&gadlist;
    int sizew    = SizeImage->Width;
    int sizeh    = SizeImage->Height;
    int bw      = (ScreenResolution == SYSISIZE_LOWRES) ? 1 : 2;
    int i;

    /*
     *        First, create the arrows for the scroll bars. Gad starts off
     *        pointing to gadlist, which will receive the pointer to the
     *        first gadget we create.
     */
    ScrollArrows[0].widthoffset  =
    ScrollArrows[1].widthoffset  = 1 - sizew;
    ScrollArrows[2].heightoffset =
    ScrollArrows[3].heightoffset = 1 - sizeh;

    for (i = 0; i < 4; i++) {
        struct ScrollData *scd = &ScrollArrows[i];
        int gadid = scd->gadgetid;
        struct Image *img;

        img = (struct Image *)
                NewObject(NULL,    "sysiclass",
                          SYSIA_DrawInfo,    ScreenDI,
                          SYSIA_Which,        scd->imagetype,
                          SYSIA_Size,        ScreenResolution,
                          TAG_END);
        if (!img)
            goto sgad_failed;
        ScrollImage[i] = img;

        gad = (struct Gadget *)
                NewObject(NULL,                "buttongclass",
                          GA_ID,            gadid,
                          GA_Immediate,        TRUE,
                          GA_Image,            img,
                          GA_Width,            img->Width,
                          GA_Height,        img->Height,
                          GA_Previous,        gad,
                          GA_RelVerify,        TRUE,
                          scd->borderpos,    TRUE,
                          GA_RelRight,        scd->widthscale * img->Width +
                                              scd->widthoffset,
                          GA_RelBottom,        scd->heightscale * img->Height +
                                              scd->heightoffset,
                          ICA_TARGET,        ICTARGET_IDCMP,
                          TAG_END);
        if (!gad)
            goto sgad_failed;
        Gadget[gadid] = gad;
    }
    /*
     *        Now create our two BOOPSI scroll gadgets in the window border
     */
    gad = (struct Gadget *)NewObject(NULL,                 "propgclass",
                                     GA_ID,                GID_HSCROLLER,
                                     PGA_Freedom,        FREEHORIZ,
                                     PGA_NewLook,        TRUE,
                                     PGA_Borderless,    TRUE,
                                     PGA_Top,            LeftCol,
                                     PGA_Visible,        BoxCols,
                                     PGA_Total,            BufferWidth,
                                     GA_Left,            3,
                                     GA_RelBottom,        3 - sizeh,
                                     GA_RelWidth,        -sizew - 5 -
                                                        ScrollImage[0]->Width -
                                                        ScrollImage[1]->Width,
                                     GA_Height,            sizeh - 4,
                                     GA_Previous,        gad,
                                     GA_BottomBorder,    TRUE,
                                     ICA_TARGET,        ICTARGET_IDCMP,
                                     ICA_MAP,            RZ_MapTags,
                                     TAG_END);
    if (!gad)
        goto sgad_failed;
    Gadget[GID_HSCROLLER] = gad;

    gad = (struct Gadget *)NewObject(NULL,                 "propgclass",
                                     GA_ID,                GID_VSCROLLER,
                                     PGA_Freedom,        FREEVERT,
                                     PGA_NewLook,        TRUE,
                                     PGA_Borderless,    TRUE,
                                     PGA_Top,            TopSeq - FirstSeq,
                                     PGA_Visible,        BoxRows,
                                     PGA_Total,            EndSeq - FirstSeq + 1,
                                     GA_RelRight,        bw - sizew + 3,
                                     GA_Top,            TitlebarHeight + 1,
                                     GA_Width,            sizew - bw - bw - 4,
                                     GA_RelHeight,        -TitlebarHeight -
                                                        ScrollImage[2]->Height-
                                                        ScrollImage[3]->Height-
                                                        sizeh - 2,
                                     GA_RightBorder,    TRUE,
                                     GA_Previous,        gad,
                                     ICA_TARGET,        ICTARGET_IDCMP,
                                     ICA_MAP,            RZ_MapTags,
                                     TAG_END);
    if (!gad)
        goto sgad_failed;
    Gadget[GID_VSCROLLER] = gad;
    return (gadlist);

sgad_failed:
    FreeScrollGadgets();
    return (NULL);
}

/*
 *        CreateMainGadgets(width, height, statusline)
 *
 *        Creates the gadgets for the main SnoopDos window, assuming a window
 *        of size width x height. MainGadList will point to the list of
 *        gadgets when completed. Returns NULL if unsuccessful, or MainGadList
 *        if successful.
 *
 *        Statusline is a flag that says whether or not the status gadget is
 *        to be created.
 *
 *        There are basically seven possible gadget layouts:
 *
 *            - 4 x 3 grid with status line on top
 *            - 4 x 2 grid with no status line
 *            - 6 x 2 grid with status line occupying the upper 4 left spaces
 *            - 8 x 1 grid with no status line
 *            - 12 x 1 grid with status line
 *          - 0 grid with no gadgets or status line
 *          - 1 line grid with status line but no gadgets
 *
 *        The first two are used when the window is narrow; the second two
 *        when the window is wider. We use colwidth[0] to hold the width
 *        of the narrow gadgets, colwidth[1] for the wide gadgets, and
 *        colwidth[2] for the status line gadget.
 *
 *        To allow us to conveniently replace one gadget definition with
 *        another, we use the concept of invisible buttons -- these are
 *        like normal buttons, but their X position is set way off to the
 *        left of the window where they won't be displayed; to reveal
 *        the buttons, we simply restore their X position and make the
 *        X position of a different button negative.
 *
 *        Finally, we have toggle buttons which flip flop between on and off.
 *        These are defined as MAIN_NARROW_TOGGLE.
 */
struct Gadget *CreateMainGadgets(struct TextAttr *gadgetfa,
                                 struct TextAttr *bufferfa,
                                 int width, int height, int statusline)
{
    struct MainGadgets *mg;
    struct NewGadget ng;
    struct TextFont *font;
    struct Gadget *gadlist;
    struct Gadget *gad;
    UWORD colwidth[MAIN_NUMWIDTHS];
    WORD  colpos[12];
    UWORD spacing;                /* Spacing between gadget tops                */
    UWORD yoffset;                /* Offset of first gadget top in window        */
    int fonty;                    /* Y height of gadget font                    */
    int bfontx;                    /* X height of buffer font                    */
    int bfonty;                    /* Y height of buffer font                    */
    int bfontbaseline;            /* Baseline of buffer font                    */
    int innerwidth;                /* Usable width of window                    */
    int extraspace;                /* Spare space inbetween buffer and gadgets    */
    int gheight;                /* Height of a single gadget                */
    int width4;                    /* Minimum width needed for 4 x 3 gadgets    */
    int width6;                    /* Minimum width needed for 6 x 2 gadgets    */
    int width8;                    /* Minimum width needed for 8 x 1 gadgets    */
    int width12;                /* Minimum width needed for 12 x 1 gadgets    */
    int gridtype;                /* Grid type for gadget layout                */
    int numrows;                /* Number of rows of gadgets involved        */
    int gadg_gap;                /* Aspect-corrected gap between gadget rows    */
    int margin = MAIN_MARGIN;    /* Gadget margin at left edge of window        */
    int boxmaxwidth;            /* Temporary width of listview box            */
    int boxheight;                /* Temporary height of listview box            */

    int bordright  = SizeImage->Width;
    int bordbot    = SizeImage->Height;

/*
 *        Quick defines for our internal grid arrangements
 */
#define FOUR_BY_THREE    0
#define SIX_BY_TWO        1
#define EIGHT_BY_ONE    2
#define TWELVE_BY_ONE    3

    if (MainGadList)
        FreeMainGadgets();

    if (!MainVI) {
        MainVI = GetVisualInfoA(SnoopScreen, NULL);
        if (!MainVI)
            return (NULL);
    }
    font = MyOpenFont(gadgetfa);
    if (!font)
        return (NULL);

    BufferFont = MyOpenFont(bufferfa);
    if (!BufferFont) {
        CloseFont(font);
        return (NULL);
    }
    fonty            = font->tf_YSize;
    bfontx            = BufferFont->tf_XSize;
    bfonty            = BufferFont->tf_YSize;
    bfontbaseline    = BufferFont->tf_Baseline;

    if (SquareAspect) {
        VBorderGap   = 2;
        gadg_gap     = 3;
    } else {
        VBorderGap   = 1;
        gadg_gap     = 2;
    }

    gheight        = fonty + GadgetHeight;
    spacing     = gheight + gadg_gap;

    colwidth[MAIN_NARROW]         = MaxTextLen(font, MainWidthLeftText)  + 12;
    colwidth[MAIN_WIDE]             = MaxTextLen(font, MainWidthRightText) + 12;

    /*
     *        First, check if window is wide enough for gadgets. If not,
     *        then fail.
     */
    innerwidth = width - BorderLeft - bordright;

    if ((colwidth[MAIN_NARROW]+colwidth[MAIN_WIDE]+margin) * 2 > innerwidth) {
        CloseFont(font);
        CloseFont(BufferFont);
        BufferFont = NULL;
        return (NULL);
    }

    /*
     *        Now calculate how many columns our fake listview can hold using
     *        the current font, and use this to adjust our margins accordingly.
     *
     *        The '4' in boxmaxwidth comes from 2 pixels for the left and right
     *        of the box (the borders)
     */
    boxmaxwidth    = innerwidth - 2*BOX_LEFT_MARGIN - 4;
    BoxCols        = (boxmaxwidth / bfontx);

    width4        = colwidth[MAIN_NARROW] * 2 + colwidth[MAIN_WIDE] * 2;
    width6        = colwidth[MAIN_NARROW] * 4 + colwidth[MAIN_WIDE] * 2;
    width8        = colwidth[MAIN_NARROW] * 4 + colwidth[MAIN_WIDE] * 4;
    width12        = colwidth[MAIN_NARROW] * 8 + colwidth[MAIN_WIDE] * 4;
    colpos[0]    = BorderLeft + margin;
    innerwidth -= margin * 2;

    if (GadgetsLine) {
        if (statusline && width12 <= innerwidth) {
            /*
             *        Setup layout for 12 x 1 grid
             */
            int totalspace = innerwidth - width12;
            int i;

            for (i = 1; i < 8; i++)
                colpos[i] = colpos[0] + colwidth[MAIN_NARROW] * i
                                      + (totalspace*i)/11;
            for (i = 8; i < 12; i++)
                colpos[i] = colpos[0] + colwidth[MAIN_NARROW] * 8
                                      + colwidth[MAIN_WIDE]   * (i-8)
                                      + (totalspace*i)/11;

            /*
             *        We always ensure that there is at least two pixels
             *        between the end of the status line and the beginning
             *        of the next gadget, otherwise we get a nasty artifact
             *        where the identically-coloured white borders meet.
             */
            colwidth[MAIN_STATUS] = colpos[3] - colpos[0] +
                                    colwidth[MAIN_NARROW];
            if ((colpos[0] + colwidth[MAIN_STATUS] + 2) > colpos[4])
                colwidth[MAIN_STATUS] = colpos[4] - colpos[0] - 2;

            gridtype = TWELVE_BY_ONE;
            numrows  = 1;
        } else if (statusline && width6 <= innerwidth) {
            /*
             *        Setup layout for 6 x 2 grid.
             */
            int totalspace = innerwidth - width6;
            int i;

            for (i = 1; i < 4; i++)
                colpos[i] = colpos[0] + colwidth[MAIN_NARROW]*i +
                             (totalspace*i)/5;

            colwidth[MAIN_STATUS] = colpos[3] - colpos[0] +
                                    colwidth[MAIN_NARROW];

            colpos[5]    = width - bordright - margin - colwidth[MAIN_WIDE];
            colpos[4]    = colpos[5] - colwidth[MAIN_WIDE] - totalspace/5;

            /*
             *        If there isn't at least 2 pixels between the status line
             *        and the adjacent wide gadget, reduce the size of each
             *        wide gadget by 1 pixel (2 pixels in total) to prevent
             *        a nasty clash between the two gadget edges.
             */
            if ((colpos[0] + colwidth[MAIN_STATUS] + 2) > colpos[4]) {
                colpos[4] += 2;
                colpos[5]++;
                colwidth[MAIN_WIDE]--;
            }
            gridtype    = SIX_BY_TWO;
            numrows      = 2;

        } else if (!statusline && width8 <= innerwidth) {
            /*
             *        Setup layout for 8 x 1 grid
             */
            int totalspace = innerwidth - width8;
            int i;

            for (i = 1; i < 4; i++)
                colpos[i] = colpos[0] + colwidth[MAIN_NARROW]*i +
                            (totalspace*i)/7;

            for (i = 4; i < 8; i++)
                colpos[i] = colpos[0] + colwidth[MAIN_NARROW] * 4
                                      + colwidth[MAIN_WIDE]   * (i-4)
                                      + (totalspace*i)/7;
            gridtype = EIGHT_BY_ONE;
            numrows     = 1;

        } else {
            /*
             *        Setup layout for 4 x 3 grid
             */
            int totalspace = (innerwidth - width4);

            colwidth[MAIN_STATUS] = width - bordright - margin - colpos[0];
            colpos[3]    = width - bordright - margin - colwidth[MAIN_WIDE];
            colpos[1]    = colpos[0] + colwidth[MAIN_NARROW] + totalspace/3;
            colpos[2]    = colpos[3] - colwidth[MAIN_WIDE]   - totalspace/3;
            gridtype    = FOUR_BY_THREE;
            if (statusline)
                numrows     = 3;
            else
                numrows  = 2;
        }
    } else {
        /*
         *        No gadget line, so set all the gadget positions to a
         *        negative value to ensure the gadgets stay hidden, and
         *        create or don't create a status line as appropriate.
         */
        int i;

        colwidth[MAIN_STATUS] = innerwidth;
        gridtype              = TWELVE_BY_ONE;
        numrows               = 1;
        for (i = 1; i < 12; i++)
            colpos[i] = INVIS_LEFT_EDGE;    /* Gadget off left-hand edge */

        if (!statusline) {
            numrows   = 0;
            colpos[0] = INVIS_LEFT_EDGE;
        }
    }
    colwidth[MAIN_NARROW_TOGGLE] = colwidth[MAIN_NARROW];
    colwidth[MAIN_WIDE_INVIS]     = colwidth[MAIN_WIDE];

    /*
     *        Next, calculate how many lines we can fit in the main buffer
     *        display. The total vertical margin is fonty + 8 + BarHeight
     *        pixels, which is distributed as follows:
     *
     *                    ----titlebar----
     *                  <1 pixel border>
     *                    4 pixel gap
     *                    Column headings
     *                    <VBorderGap>
     *                    2 pixels of border
     *                    <VBorderGap>
     *                    Lines of text
     *                    <VBorderGap>
     *                    (1 pixel border)
     *
     *        And in addition, if we have gadgets enabled:
     *
     *                    (1 pixel border)
     *                    <gadg_gap>
     *                    ---gadget area---
     *                    <gadg_gap>
     *                    (1 pixel border)
     *                    ---bottom border---
     *
     *        The minimum spacing between gadgets is also gadg_gap.
     *        Each individual gadget has a height 6 pixels higher than
     *        the font size.
     *
     *        The catch is to take the <any additional space> and distribute
     *        it equally between the various gadget spaces etc. For N rows
     *        of gadgets, this implies that there are (N+1) "gaps" that can
     *        have vertical space added to them.
     */
    BoxLeft            = BorderLeft;
    BoxWidth        = width - bordright - BoxLeft;
    BoxInLeft        = BoxLeft + BOX_LEFT_MARGIN + 2;
    BoxInWidth        = bfontx * BoxCols;
    BoxCharWidth    = bfontx;
    BoxCharHeight    = bfonty;

    yoffset            = height - bordbot - spacing * numrows - gadg_gap;
    BoxSpacing      = bfonty + BoxInterGap;
    if (SquareAspect) {
        BoxTop            = TitlebarHeight + 6 + bfonty;
        BoxHeaderLine     = TitlebarHeight + 4 + bfontbaseline;
    } else {
        BoxTop            = TitlebarHeight + 5 + bfonty;
        BoxHeaderLine     = TitlebarHeight + 3 + bfontbaseline;
    }
    if (numrows)
        boxheight   = yoffset - gadg_gap - VBorderGap*3 - BoxTop-2;
    else
        boxheight    = height - bordbot - BoxTop - 2*VBorderGap - 2;
    BoxRows    = (boxheight + BoxInterGap) / BoxSpacing;
    if (numrows)
        BoxHeight    = BoxRows * BoxSpacing - BoxInterGap + 2*VBorderGap + 2;
    else
        BoxHeight    = height - bordbot - BoxTop;

    BoxLowest    = BoxTop   + BoxHeight + VBorderGap;
    BoxInTop    = BoxTop   + VBorderGap + 1;
    BoxBaseline    = BoxInTop + bfontbaseline;
    BoxInHeight    = BoxRows * BoxSpacing - BoxInterGap;

    InitMainMargins();

    /*
     *        Now get ready to create the button and status line gadgets
     *        We always create the gadgets, even if they're not currently
     *        being displayed.
     */
    ng.ng_TextAttr        = gadgetfa;
    ng.ng_VisualInfo    = MainVI;
    ng.ng_Flags         = PLACETEXT_IN;

    ng.ng_GadgetText    = "";
    ng.ng_GadgetID        = 0;

    gadlist = NULL;
    gad = CreateContext(&gadlist);
    if (!gad)
        goto mgad_failed;

    /*
     *        Now, the buttons and status line gadget. At this point,
     *        we distribute any additional space that we have left between
     *        the lower scroll bar and the current start of the gadget
     *        grid (aka yoffset).
     */
    extraspace        = yoffset - (BoxTop + BoxHeight);
    yoffset           -= extraspace - extraspace/(numrows+1) -
                      ((extraspace % (numrows+1)) + 1)/2;
    spacing           += extraspace / (numrows + 1);
    yoffset           += gadg_gap;
    ng.ng_Height    = gheight;

    if (gridtype == FOUR_BY_THREE && !statusline)
        yoffset -= spacing;    /* Bias to allow for invisible status bar */

    for (mg = &MainGadgs[0]; mg->gadgid; mg++) {
        switch (gridtype) {
            case FOUR_BY_THREE:
                ng.ng_LeftEdge     = colpos[mg->col4];
                ng.ng_TopEdge      = yoffset + spacing * mg->row4;
                ng.ng_Width        = colwidth[mg->widthtype];
                break;

            case SIX_BY_TWO:
                ng.ng_LeftEdge     = colpos[mg->col6];
                ng.ng_TopEdge      = yoffset + spacing * mg->row6;
                ng.ng_Width        = colwidth[mg->widthtype];
                break;

            case EIGHT_BY_ONE:
                ng.ng_LeftEdge     = colpos[mg->col8];
                ng.ng_TopEdge      = yoffset;
                ng.ng_Width        = colwidth[mg->widthtype];
                break;

            case TWELVE_BY_ONE:
                ng.ng_LeftEdge     = colpos[mg->col12];
                ng.ng_TopEdge      = yoffset;
                ng.ng_Width        = colwidth[mg->widthtype];
                break;
        }
        ng.ng_GadgetText    = MSG(mg->stringid);
        ng.ng_GadgetID        = mg->gadgid;

        if (mg->gadgid == GID_STATUS) {
            if (statusline) {
                int len = GetTextLen(font, MSG(mg->stringid)) + 9;

                ng.ng_LeftEdge += len;
                ng.ng_Width       -= len;
                ng.ng_Flags        = PLACETEXT_LEFT;
                gad = CreateGadget(TEXT_KIND, gad, &ng,
                                   GT_Underscore,    '_',
                                   GTTX_Text,        StatusLineText,
                                   GTTX_Border,        TRUE,
                                   TAG_DONE);
                ng.ng_Flags           = PLACETEXT_IN;
                if (!gad)
                    goto mgad_failed;
                Gadget[GID_STATUS] = gad;
            } else {
                Gadget[GID_STATUS] = NULL;
            }
        } else {
            gad = CreateGadget(BUTTON_KIND, gad, &ng,
                               GT_Underscore,    '_',
                               TAG_DONE);
            if (!gad)
                goto mgad_failed;

            if (mg->widthtype == MAIN_NARROW_TOGGLE)
                gad->Activation |= GACT_TOGGLESELECT;

            if (mg->widthtype == MAIN_WIDE_INVIS)
                gad->LeftEdge = INVIS_LEFT_EDGE;

            Gadget[mg->gadgid] = gad;
        }
        AddKeyShortcut(MainKeyboard, mg->gadgid, mg->stringid);
    }
    LogButtonLeft = Gadget[GID_OPENLOG]->LeftEdge;
    SetLogGadget(DefaultLogMode, LG_NOREFRESH);

    /*
     *        Now some additional initialisation for the Pause
     *        and Disable gadgets in case they're initially set
     */
    if (Paused)        Gadget[GID_PAUSE  ]->Flags |= GFLG_SELECTED;
    if (Disabled)    Gadget[GID_DISABLE]->Flags |= GFLG_SELECTED;

    /*
     *        Now a quick check to see if we have opened commodities.library
     *        yet -- if we haven't, then disable the hide gadget.
     */
    if (CurSettings.Setup.HideMethod == HIDE_NONE)
        Gadget[GID_HIDE]->Flags |= GFLG_DISABLED;

    return (gadlist);

mgad_failed:
    FreeMainGadgets();
    CloseFont(font);
    return (NULL);
}

/*
 *        RecalcMainWindow(width, height, refresh)
 *
 *        Updates the gadgets for the main window to reflect the new size,
 *        and renders the changes to the screen. If the refresh parameter
 *        is REDRAW_GADGETS, then the function will automatically redraw
 *        the gadgets in the window, otherwise this must be done by hand
 *        (or perhaps automatically if Intuition generates an IDCMP_REFRESH
 *        message after a resize event!)
 *
 *        Returns FALSE if something went wrong (in which case the caller
 *        is responsible for closing the main window) and displaying an
 *        error message.
 */
BOOL RecalcMainWindow(int width, int height, int dorefresh)
{
    struct RastPort *rport = MainWindow->RPort;
    int saveleft    = BoxLeft;
    int savewidth    = BoxWidth;
    int saveheight    = BoxHeight;
    int oldrows     = BoxRows;
    int startrow;

    if (!MainWindow)
        return (TRUE);

    if (MainGadList && !RemovedGadgets)
        RemoveGList(MainWindow, MainGadList, -1);

    MainGadList = CreateMainGadgets(CurMainGadgetFA, CurMainBufferFA,
                                       width, height, StatusLine);
    if (!MainGadList)
        return (FALSE);

    UpdateMainHScroll();
    UpdateMainVScroll();
    if (BoxWidth == savewidth && BoxLeft == saveleft && !ChangedSpacing) {
        if (BoxHeight == saveheight)
            /*
             *        Only erase from bottom of scroll box down since the
             *        rest hasn't actually changed at all.
             */
            startrow = BoxLowest;
        else {
            startrow = BoxTop + MIN(BoxHeight, saveheight) - 1;
            startrow = MAX(startrow, TitlebarHeight);
        }
    } else
        startrow = TitlebarHeight;

    SetDrMd(rport, JAM1);
    SetAPen(rport, 0);
    AddGList(MainWindow, MainGadList, -1, -1, NULL);

    if (startrow == BoxLowest) {
        /*
         *        If we are only refeshing the bottom part of the screen,
         *        don't bother erasing the top half -- it looks much
         *        cleaner.
         */
        if (StatusLine || GadgetsLine) {
            // SetAPen(rport, 4);    /* Makes gadget bground gray (nice!) */
            RectFill(rport, BoxLeft + 2, BoxTop + BoxHeight + 1,
                            BoxLeft + BoxWidth - 3,
                            MainWindow->Height - MainWindow->BorderBottom - 1);
            DrawBevelBox(rport, BoxLeft, BoxTop + BoxHeight, BoxWidth,
                                MainWindow->Height - MainWindow->BorderBottom -
                                                     BoxTop - BoxHeight,
                                GT_VisualInfo,    MainVI,
                                TAG_DONE);
        }
        if (dorefresh)
            RefreshGList(MainGadList, MainWindow, NULL, -1);
    } else {
        startrow = MAX(TitlebarHeight, startrow - BoxSpacing - 3);
        RectFill(rport, MainWindow->BorderLeft, startrow,
                 width  - MainWindow->BorderRight  - 1,
                 height - MainWindow->BorderBottom - 1);
        if (dorefresh)
            RefreshGList(MainGadList, MainWindow, NULL, -1);
        /*
         *        If we are currently at the end of the display, we want to
         *        ensure that we scroll to the end after refreshing the window.
         */
        if (TopSeq + oldrows > EndSeq) {
            /*
             *        Force redraw from buffer end after resize
             */
            TopSeq   = EndSeq;
            TopEvent = EndEvent;
        }
        RedrawMainWindow();
        UpdateMainVScroll();
    }
    GT_RefreshWindow(MainWindow, NULL);
    CurWindowWidth  = MainWindow->Width;
    CurWindowHeight = MainWindow->Height;
    ChangedSpacing  = 0;
    return (TRUE);
}

/*
 *        SetMenuOptions()
 *
 *        Configures the main window's menu strip to match the currently
 *        selected options (e.g. Pause/Disable, Text Spacing, window type,
 *        icon type, etc.)
 *
 *        Call whenever settings change.
 *
 */
void SetMenuOptions(void)
{
    struct MenuItem *item;

#define SetMenuState(menunum, val) \
    item = ItemAddress(MainWinMenu, menunum); \
    item->Flags = (item->Flags & ~CHECKED) | ((val) ? CHECKED : 0)

    if (MainWindow && MainWinMenu) {
        int curpri = SysBase->ThisTask->tc_Node.ln_Pri;
        int i;

        SetMenuState(MENU_PAUSE,      Paused);
        SetMenuState(MENU_DISABLE,      Disabled);
        SetMenuState(MENU_AUTO_OPEN,  AutoOpen);
        SetMenuState(MENU_DIS_HIDDEN, DisableOnHide);
        SetMenuState(MENU_STATUS,      StatusLine);
        SetMenuState(MENU_GADGETS,      GadgetsLine);
        SetMenuState(MENU_ICONS,      CreateIcons);
        SetMenuState(MENU_SIMPLE,      CurSettings.SimpleRefresh);
        SetMenuState(MENU_SMART,      !CurSettings.SimpleRefresh);
        SetMenuState(MENU_AL_LEFT,      !RightAligned);
        SetMenuState(MENU_AL_RIGHT,      RightAligned);
        SetMenuState(MENU_SPACING0,      BoxInterGap == 0);
        SetMenuState(MENU_SPACING1,      BoxInterGap == 1);
        SetMenuState(MENU_SPACING2,      BoxInterGap == 2);

        SetMenuState(MENU_ROWQUAL_ANY,      RowQual == ROWQUAL_ANY);
        SetMenuState(MENU_ROWQUAL_NONE,      RowQual == ROWQUAL_NONE);
        SetMenuState(MENU_ROWQUAL_SHIFT,  RowQual == ROWQUAL_SHIFT);
        SetMenuState(MENU_ROWQUAL_ALT,      RowQual == ROWQUAL_ALT);
        SetMenuState(MENU_ROWQUAL_CTRL,      RowQual == ROWQUAL_CTRL);
        SetMenuState(MENU_ROWQUAL_ALL,      RowQual == ROWQUAL_ALL);

        if (CurSettings.Setup.HideMethod == HIDE_NONE)
            OffMenu(MainWindow, MENU_HIDE);
        else
            OnMenu(MainWindow,    MENU_HIDE);

        if (LogActive) {
            OffMenu(MainWindow,    MENU_OPENLOG);
            OnMenu(MainWindow,    MENU_CLOSELOG);
        } else {
            OnMenu(MainWindow,    MENU_OPENLOG);
            OffMenu(MainWindow,    MENU_CLOSELOG);
        }

        /*
         *        We calculate our current priority on the fly. This
         *        means we'll always be up-to-date, even if someone
         *        changes our priority from outside the program.
         */
        for (i = 0; i < MENU_NUMPRI; i++) {
            int subnum = MENU_CHANGEPRI | SHIFTSUB(i);
            struct MenuItem  *item  = ItemAddress(MainWinMenu, subnum);
            struct IntuiText *itext = (void *)(item->ItemFill);

            if (atoi(itext->IText) == curpri)
                item->Flags |= CHECKED;
            else
                item->Flags &= ~CHECKED;
        }
    }
}

/*
 *        SetMainHideState(state)
 *
 *        Updates the current main window titlebar, hide gadget, and
 *        menu HIDE option to reflect the given hide state.
 *
 *        It works as follows. If state is HIDE_NONE, then the titlebar
 *        is set to <none> and the gadget/menu item are ghosted. If
 *        state is not HIDE_NONE, the gadget/menu item are unghosted,
 *        and the titlebar is set to <key sequence>, unless HotKeyActive
 *        is set to 0, in which case it is set to <invalid>.
 */
void SetMainHideState(int hidestate)
{
    char title[200];
    char *keyname = CurSettings.Setup.HotKey;

    if (!HotKeyActive)
        keyname = MSG(MSG_INVALID_HOTKEY);

    if (hidestate == HIDE_NONE)
        strcpy(title, SnoopDosTitle);
    else
        mysprintf(title, SnoopDosTitleKey, keyname);

    if (strcmp(CurrentTitle, title) != 0)
        strcpy(CurrentTitle, title);

    if (MainWindow) {
        struct Gadget *gad = Gadget[GID_HIDE];
        int oldstate       = gad->Flags & GFLG_DISABLED;
        int gadpos;

        SetWindowTitles(MainWindow, CurrentTitle, (UBYTE *)-1);

        gadpos = RemoveGadget(MainWindow, gad);
        if (hidestate == HIDE_NONE)
            gad->Flags |= GFLG_DISABLED;
        else
            gad->Flags &= ~GFLG_DISABLED;

        AddGadget(MainWindow, gad, gadpos);
        if ((gad->Flags & GFLG_DISABLED) != oldstate) {
            /*
             *        Only refresh the gadget if its state changed
             */
            RefreshGList(gad, MainWindow, NULL, 1);
        }
        if (MainWinMenu) {
            if (CurSettings.Setup.HideMethod == HIDE_NONE)
                OffMenu(MainWindow, MENU_HIDE);
            else
                OnMenu(MainWindow,    MENU_HIDE);
        }
    }
}

/*
 *        OpenMainWindow()
 *
 *        Opens the main window with the scroll buffer display, arrow gadgets,
 *        and buttons. Also creates the status line gadget if necessary.
 *
 *        Returns true for success, false for failure.
 */
BOOL OpenMainWindow(void)
{
    static WORD initzoomdims[] = { 0, 0, -1, -1 };
    struct Window *win;
    struct Gadget *scrollgadlist;
    struct TextAttr *gadgetfa;
    struct TextAttr *bufferfa;
    int minx, miny;
    int menupen;
    int i;
    int width  = CurSettings.MainWinWidth;
    int height = CurSettings.MainWinHeight;
    int left   = CurSettings.MainWinLeft;
    int top    = CurSettings.MainWinTop;

    CheckSegTracker();
    if (MainWindow) {
        WindowToFront(MainWindow);
        ActivateWindow(MainWindow);
        return (TRUE);
    }
    if (!CheckForScreen())
        goto open_main_failed;

    for (i = 0; gadgetfa = MainWindowFontList[i].gadgetfa; i++) {
        bufferfa = MainWindowFontList[i].bufferfa;

        if (CalcMinMainSize(gadgetfa, bufferfa, &minx, &miny))
            break;
    }
    if (!gadgetfa)
        goto open_main_failed;

    if (width  == -1)                    width  = DEF_WINDOW_WIDTH;
    if (height == -1)                    height = DEF_WINDOW_HEIGHT;
    if (width  == 0)                    width  = CurSettings.MainWinWidth;
    if (height == 0)                    height = CurSettings.MainWinHeight;
    if (width  < minx)                     width  = minx;
    if (height < miny)                    height = miny;
    if (width  > ScreenWidth)            width  = ScreenWidth;
    if (height > ScreenHeight)            height = ScreenHeight;
    if (left   == -1)                    left   = 0;
    if (top    == -1)                    top    = SnoopScreen->BarHeight + 2;

    initzoomdims[2] = ScreenWidth;
    initzoomdims[3] = ScreenHeight;

    ShowBuffer(TopSeq, DISPLAY_NONE);    /* Ensure scroll vars are up to date */

    MainGadList   = CreateMainGadgets(gadgetfa, bufferfa,
                                     width, height, StatusLine);
    scrollgadlist = CreateScrollGadgets();
    if (!scrollgadlist || !MainGadList)
        goto open_main_failed;

    Gadget[GID_ENDSCROLL]->NextGadget = MainGadList;

    CurMainGadgetFA = gadgetfa;
    CurMainBufferFA = bufferfa;

    SetMainHideState(CurSettings.Setup.HideMethod);    /* Make title up to date */
    win = OpenWindowTags(NULL,
                         WA_Title,            CurrentTitle,
                         WA_IDCMP,            IDCMP_CLOSEWINDOW     |
                                             IDCMP_REFRESHWINDOW     |
                                            IDCMP_NEWSIZE         |
                                            IDCMP_CHANGEWINDOW     |
                                            IDCMP_RAWKEY         |
                                            IDCMP_MENUPICK         |
                                            IDCMP_IDCMPUPDATE     |
                                            IDCMP_GADGETDOWN     |
                                            IDCMP_MOUSEBUTTONS     |
                                            IDCMP_MOUSEMOVE         |
                                            IDCMP_MENUHELP          |
                                            IDCMP_SIZEVERIFY     |
                                            IDCMP_INACTIVEWINDOW |
                                            BUTTONIDCMP,
                         WA_Left,              left,
                         WA_Top,              top,
                         WA_Width,            width,
                         WA_Height,            height,
                         WA_Flags,            WFLG_CLOSEGADGET     |
                                             WFLG_DRAGBAR         |
                                            WFLG_DEPTHGADGET     |
                                            WFLG_ACTIVATE         |
                                            WFLG_SIZEGADGET         |
                                            WFLG_SIZEBBOTTOM     |
                                            WFLG_SIZEBRIGHT         |
                                            WFLG_NEWLOOKMENUS,
                         WA_MenuHelp,        TRUE,
                         RefreshTag,          TRUE,
                         WA_NoCareRefresh,    NoCareRefreshBool,
                         WA_PubScreen,        SnoopScreen,
                         WA_MinWidth,        minx,
                         WA_MinHeight,        miny,
                         WA_MaxWidth,        -1,
                         WA_MaxHeight,        -1,
                         WA_Zoom,            initzoomdims,
                         WA_Gadgets,        scrollgadlist,
                         TAG_DONE);
    if (!win)
        goto open_main_failed;

    MainWindow       = win;
    MainWindowPort = win->UserPort;
    MainWindowMask = 1 << MainWindowPort->mp_SigBit;

    if (DraggingColumn || DraggingRow) {
        /*
         *        If we were previously closed while a column was being dragged,
         *        reset the drag flag and signal ourselves to ensure we catch
         *        any events that arrived while output was suspended.
         */
        DraggingColumn = 0;
        DraggingRow    = 0;
        Signal(SysBase->ThisTask, NewEventMask);
    }
    RedrawMainWindow();
    // RefreshGList(MainGadList, MainWindow, NULL, -1);    /* Already done */
    GT_RefreshWindow(MainWindow, NULL);
    UpdateStatus();

    /*
     *        Now create menus for window
     */
    if (IntuitionBase->LibNode.lib_Version >= 39)
        menupen = 1;
    else
        menupen = 0;

    MainWinMenu = CreateMenus(MainMenu, GTMN_FrontPen, menupen, TAG_DONE);

    if (!MainWinMenu)
        ShowError(MSG(MSG_ERROR_CREATEMENUS));
    else {
        LayoutMenus(MainWinMenu, MainVI, GTMN_NewLookMenus, TRUE, TAG_DONE);
        SetMenuStrip(MainWindow, MainWinMenu);
        SetMenuOptions();
    }
    CurWindowWidth  = MainWindow->Width;
    CurWindowHeight = MainWindow->Height;
    AwaitingResize  = RESIZE_DONE;
    if ((SnoopScreen->Flags & SCREENTYPE) != WBENCHSCREEN) {
        /*
         *        We're running on a custom screen, so redirect system
         *        requesters to appear on this screen instead of the
         *        Workbench screen. We don't do it unconditionally, because
         *        our window title is so long that it makes the requesters
         *        look very lopsided -- still, if we're on a custom screen,
         *        it's better than nothing.
         */
        *TaskWindowPtr = MainWindow;
    }
    if (DisableNestCount)
        DisableWindow(MainWindow, &MainRequester);

    return (TRUE);

open_main_failed:
    ShowError(MSG(MSG_ERROR_OPENMAIN));
    return (FALSE);
}

/*
 *        CloseMainWindow(void)
 *
 *        Closes the main SnoopDos window
 */
void CloseMainWindow(void)
{
    *TaskWindowPtr = SaveWindowPtr;        /* Restore previous screen address */
    if (MainWindow) {
        if (MainWinMenu) {
            ClearMenuStrip(MainWindow);
            FreeMenus(MainWinMenu);
            MainWinMenu = NULL;
        }
        RecordWindowSizes();
        CloseWindow(MainWindow);
        FreeMainGadgets();
        MainWindow        = NULL;
        MainWindowMask    = 0;
    }
    FreeScrollGadgets();
    if (MainVI) {
        FreeVisualInfo(MainVI);
        MainVI = NULL;
    }
}

/*
 *        ShowStatus(msg)
 *
 *        Displays the specified message in the status line (if enabled)
 */
void ShowStatus(char *msg)
{
    strcpy(StatusLineText, msg);

    if (MainWindow) {
        GT_SetGadgetAttrs(Gadget[GID_STATUS], MainWindow, NULL,
                          GTTX_Text,    StatusLineText,
                          TAG_DONE);
    }
}

/*
 *        ReOpenMainWindow()
 *
 *        Closes and re-opens main window retaining current size but
 *        taking into account new font, spacing, refresh type, etc.
 *        If another window is specified, then that window is brought
 *        to the front after the main window is reopened.
 */
void ReOpenMainWindow(void)
{
    if (MainWindow) {
        /*
         *        If we've changed spacing but not yet updated the window to
         *        reflect this, then if we are going from 0-spacing to 2-spacing,
         *        the buffer may loose a few lines. To ensure we remain at the
         *        end of the buffer if we were there to start with, we do an
         *        invisible scroll to the _very_ end, just to be safe.
         */
        if (BottomSeq >= EndSeq) {
            TopSeq     = EndSeq;
            TopEvent = EndEvent;
        }
        CloseMainWindow();
        OpenMainWindow();
    }
}

/*
 *        CheckForDirtyMainWindow()
 *
 *        Checks to see if the main Window's rastport is dirty (i.e. we did
 *        a scrollraster which was partially obscured by another window, and
 *        now we need to refresh) and redraw the window if necessary.
 *
 *        Typically called after ShowBuffer()
 */
void CheckForDirtyMainWindow(void)
{
    if (MainWindow && MainWindow->RPort->Layer->Flags & LAYERREFRESH) {
        GT_BeginRefresh(MainWindow);
        RedrawMainWindow();
        GT_EndRefresh(MainWindow, TRUE);
    }
}

/*
 *        UpdateMainHScroll(void)
 *
 *        Updates the main horizontal scrollbar to reflect the current
 *        margin settings and buffer width.
 */
void UpdateMainHScroll(void)
{
    if (MainWindow)
        SetGadgetAttrs(Gadget[GID_HSCROLLER], MainWindow, NULL,
                       PGA_Top,        LeftCol,
                       PGA_Total,    BufferWidth,
                       PGA_Visible,    BoxCols,
                       TAG_DONE);
}

/*
 *        UpdateMainVScroll(void)
 *
 *        Updates the main scrollbar to reflect the current state of play.
 *        N.b. Depends on the parameters calculated during the last call
 *        to ShowBuffer.
 */
void UpdateMainVScroll(void)
{
    if (MainWindow)
        SetGadgetAttrs(Gadget[GID_VSCROLLER], MainWindow, NULL,
                       PGA_Top,        TopSeq - FirstSeq,
                       PGA_Total,    EndSeq - FirstSeq + 1,
                       PGA_Visible,    BoxRows,
                       TAG_DONE);
}

/*
 *        ScrollHorizontal(amount)
 *
 *        Scrolls the window horizontally to the left (-ve amount) or right
 *        (+ve amount) and does the minimum amount of refresh necessary to
 *        ensure the screen is correctly updated. i.e., we use ScrollRaster()
 *        to perform the bulk of the scroll.
 */
void ScrollHorizontal(int amount)
{
    struct RastPort *rport = MainWindow->RPort;
    int       oldpos = LeftCol;
    Event *firstevent;
    int x0, y0, x1, y1;
    int h0, h1;
    int dx;
    int dxwidth;
    int saveboxleft;
    int saveleftcol;
    int saverightcol;
    int saveboxcols;

    LeftCol += amount;
    InitMainMargins();
    if (!MainWindow || LeftCol == oldpos)
        return;

    UpdateMainHScroll();

    /*
     *        Okay, we're scrolling left or right, so do a ScrollRaster for
     *        part of the amount and then use ShowBuffer() to fill in the
     *        refreshed area. If there are no events or the buffer display
     *        is now out of date, do a full refresh instead.
     *
     *        We lock semaphores for the duration to ensure that the buffer
     *        doesn't change under our feet which might lead to mismatched
     *        lines of output.
     */
    LOCK_LAYERS;
    ObtainSemaphore(&BufSem);

    dx = LeftCol - oldpos;
    dxwidth = dx * BoxCharWidth;

    firstevent = HeadNode(&EventList);
    if (!firstevent || TopSeq < firstevent->seqnum || abs(dx) > (BoxCols/2)) {
        RedrawMainWindow();
        goto unlockall;
    }

    /*
     *        Calculate co-ordinates for scroll
     */
    h0 = BoxHeaderLine + BoxInTop - BoxBaseline;
    h1 = h0 + BoxCharHeight - 1;
    y0 = BoxInTop;
    y1 = BoxInTop + BoxInHeight - 1;
    x0 = BoxInLeft;
    x1 = BoxInLeft + (RightCol - LeftCol + 1) * BoxCharWidth - 1;

    if (GfxBase->LibNode.lib_Version >= 39) {
        /*
         *        Do optimised flicker-free scroll under V39
         */
        struct Hook *oldhook;

        oldhook = InstallLayerHook(MainWindow->WLayer, LAYERS_NOBACKFILL);
        ScrollRasterBF(rport, dxwidth, 0, x0, h0, x1, y1);
        InstallLayerHook(MainWindow->WLayer, oldhook);
    } else {
        /*
         *        Do a somewhat flickering scroll under V37 -- unfortunately,
         *        we have to do the scroll in two separate parts, to avoid
         *        erasing part of the separator bar between the header and
         *        the buffer text when it is scrolled
         */
        ScrollRaster(rport, dxwidth, 0, x0, h0, x1, h1);
        ScrollRaster(rport, dxwidth, 0, x0, y0, x1, y1);
    }
    /*
     *        Finally, refresh the window section we just vacated by
     *        temporarily changing the margins
     */
    saveboxleft  = BoxInLeft;
    saveleftcol  = LeftCol;
    saverightcol = RightCol;
    saveboxcols  = BoxCols;

    if (dx < 0) {
        /*
         *        Scrolling to left so refresh left side of window
         */
        if (RightCol > -dx)
            RightCol = LeftCol - dx - 1;
        BoxCols = RightCol - LeftCol + 1;
    } else {
        /*
         *        Scrolling to right so refresh right side of window
         */
        int offset = RightCol - LeftCol + 1 - dx;
        if (offset < 0)
            goto done_scroll;

        BoxInLeft += offset * BoxCharWidth;
        LeftCol   += offset;
        BoxCols   -= offset;
    }
    if (RightCol < LeftCol)
        goto done_scroll;
    DrawHeaderLine();
    ShowBuffer(TopSeq, DISPLAY_ALL);

done_scroll:
    BoxInLeft = saveboxleft;
    LeftCol   = saveleftcol;
    RightCol  = saverightcol;
    BoxCols   = saveboxcols;

    /*
     *        All done, now we can release semaphores and exit
     */
unlockall:
    ReleaseSemaphore(&BufSem);
    UNLOCK_LAYERS;
    CheckForDirtyMainWindow();
}

/*
 *        DoArrowScrolling()
 *
 *        Scrolls window in the direction of the specified arrow
 *        (GID_UPARROW, GID_DOWNARROW, GID_LEFTARROW or GID_RIGHTARROW)
 *        and by the specified amount (usually 1 but sometimes more).
 */
void DoArrowScrolling(int arrowtype, int amount)
{
    int changedvert = 0;
    int horizadjust = 0;
    int newseq;

    /*
     *        If we're currently dragging columns, we ignore any attempts
     *        at scrolling since it can cause problems with the format
     *        being screwed up.
     */
    if (DraggingColumn || DraggingRow)
        return;

    switch (arrowtype) {
        case GID_UPARROW:
            /*
             *        Move up in a message
             */
            if (TopSeq > FirstSeq) {
                changedvert = 1;
                newseq        = TopSeq - amount;
                if (newseq < 1)
                    newseq = 1;
            }
            break;

        case GID_DOWNARROW:
            /*        We do a clever optimisation here for power users:
             *        if SnoopDos is Paused and is at the end of the
             *        buffer, then clicking on the down arrow (normally
             *        a no-op) will have the same effect as selecting
             *        single step.
             */
            if (Paused && BottomSeq >= EndSeq)
                SingleStep();

            changedvert = 1;
            newseq        = TopSeq + amount;
            break;

        case GID_LEFTARROW:
            if (LeftCol > 0)
                horizadjust =- amount;
            break;

        case GID_RIGHTARROW:
            if (LeftCol + BoxCols <= BufferWidth)
                horizadjust = amount;
            break;
    }
    if (MainWindow) {
        if (horizadjust)
            ScrollHorizontal(horizadjust);

        if (changedvert) {
            InitMainMargins();
            ShowBuffer(newseq, DISPLAY_QUICK);
            UpdateMainVScroll();
            CheckForDirtyMainWindow();
        }
    }
}

/*
 *        InvertColumn(pos)
 *
 *        Inverts the column drawn at the specified column position, relative
 *        to the left margin of the box (i.e. 0 ... BoxCols-1)
 *
 *        mode is INVERT_FULLBOX or INVERT_HEADER, depending on whether just
 *        the top of the column or the entire column is to be inverted. This
 *        allows for optimised updates if a column's position hasn't actually
 *        changed but the header still needs to be redrawn.
 */
void InvertColumn(int col, int mode)
{
    struct RastPort *rport = &InvertRP;
    int bfontbaseline       = BufferFont->tf_Baseline;
    int y1 = BoxHeaderLine - bfontbaseline;
    int y2 = (mode == INVERT_HEADER ? (BoxTop - 1) : (BoxInTop + BoxInHeight));

    if (col >= 0 && col < BoxCols) {
        int x = BoxInLeft + col * BoxCharWidth + BoxCharWidth / 2;

        RectFill(rport, x, y1, x+1, y2);
    }
}

/*
 *        StartDragCol(x)
 *
 *        Starts dragging a column displayed in the main window at absolute
 *        coordinate X.
 *
 *        Initialises all the variables associated with this and returns
 *        with dragging enabled.
 */
void StartDragCol(int x)
{
    EventFormat *ef;
    int clickcol;

    if (BufferEFormat[0].type == EF_END)    /* Skip empty event formats */
        return;

    /*
     *        Now scan event buffer and figure out which heading we match
     *        Note that the user must click on the event heading itself,
     *        or it won't count (i.e. clicking on space between columns
     *        doesn't work) -- this is to prevent confusion.
     */
    clickcol = LeftCol + ((x - BoxInLeft) / BoxCharWidth);
    {
        /*
         *        Select the column to drag
         */
        int colpos = 0;
        int len    = 0;

        for (ef = BufferEFormat; ef->type != EF_END; ef++) {
            if (clickcol >= colpos && clickcol < (colpos + ef->width + 1))
                break;

            colpos += ef->width + 1;
        }
        /*
         *        Now check if the clickcol should affect the left or right
         *        sides of the selected column. The leftmost column is a
         *        special case (in that we always choose the righthand column
         *        rather  the preceding lefthand, since you can't drag the
         *        lefthand column any further to the left).
         *
         *        In the normal case, if there is any blank area to the right of
         *        the column, then clicking in the blank area activates the
         *        the right column adjustment, else the left column adjustment.
         *        If there is no blank area, then clicking in the rightmost
         *        column activates the right column, else the left column.
         */
        if (ef->type != EF_END)
            len = strlen(MSG(ef->titlemsgid));

        if (ef == BufferEFormat || ef->type == EF_END ||
            clickcol >= (colpos + MIN(ef->width-1, len)))
        {
            /*
             *        Adjusting the righthand side of the selected column
             */
            if (ef->type == EF_END) {
                DragEvent       = ef-1;
                SelectEvent       = ef-1;
                SelectStartCol = colpos - SelectEvent->width - 1;
            } else {
                SelectEvent    = ef;
                SelectStartCol = colpos;
                DragEvent         = ef;
            }
            DragOrigColWidth = DragEvent->width;
            NextOrigColWidth = (ef+1)->width;
        } else {
            /*
             *        Adjusting the lefthand side of the selected column
             */
            SelectEvent      = ef;
            SelectStartCol     = colpos;
            DragEvent           = ef-1;
            DragOrigColWidth = DragEvent->width;
            NextOrigColWidth = ef->width;
        }
    }
    OrigLeftCol        = LeftCol;
    OrigBufWidth    = BufferWidth;
    ClickStartCol    = clickcol;
    ClickCurCol        = clickcol;
    DraggingColumn     = 1;
    MovedColumn        = 0;
    DrawHeaderLine();
    /*
     *        Now initialise the rastport we use for the inverted column
     *        (we use a separate rastport for speed; otherwise, we have
     *        to keep initialising it, which is rather slow.)
     */
    InvertRP = *(MainWindow->RPort);
    if (GfxBase->LibNode.lib_Version >= 39)
        SetWriteMask(&InvertRP, 1);
    else
        InvertRP.Mask = 1;
    SetAPen(&InvertRP, 1);
    SetBPen(&InvertRP, 0);
    SetDrMd(&InvertRP, COMPLEMENT);

    InvertColumn(SelectStartCol-LeftCol-1,                     INVERT_FULLBOX);
    InvertColumn(SelectStartCol-LeftCol+SelectEvent->width, INVERT_FULLBOX);

    ReportMouse(TRUE, MainWindow);
    MainWindow->IDCMPFlags |= IDCMP_INTUITICKS;
    MainWindow->Flags      |= WFLG_RMBTRAP;    /* Need to detect RMB for cancel */
}

/*
 *        SizeColumn(eventptr, newwidth, movetype)
 *
 *        Adjusts the width of the specified event entry to the new
 *        value given, performing any scrolling and updating of the
 *        main window that may be required.
 *
 *        movetype is MOVECOL_FREE to allow free movement between the
 *        columns to the left and right, or MOVECOL_FIXED to force
 *        the columns to the right to move along with the column being
 *        sized.
 */
void SizeColumn(EventFormat *ef, int newwidth, int movetype)
{
    EventFormat *nextef = ef+1;
    int oldleftcol         = LeftCol;
    int dwidth            = newwidth - ef->width;
    int oldbufwidth        = BufferWidth;
    int oldpos1            = SelectStartCol - LeftCol - 1;
    int oldpos2            = SelectStartCol - LeftCol + SelectEvent->width;
    int newpos1;
    int newpos2;
    int mode1;
    int mode2;

    if (dwidth == 0)
        return;

    if (movetype == MOVECOL_FREE &&  nextef->type    != EF_END     &&
                                    (nextef+1)->type != EF_END) {
        /*
         *        Bound movement so that we don't make the column to the
         *        right of the main column exceed its bounds (in either
         *        direction).
         */
        int nextwidth = nextef->width - dwidth;

        if (nextwidth < 1)                nextwidth = 1;
        if (nextwidth > MAX_FIELD_LEN)    nextwidth = MAX_FIELD_LEN;

        if (nextwidth != (nextef->width - dwidth)) {
            dwidth   = nextef->width - nextwidth;
            newwidth = ef->width + dwidth;
        }
        nextef->width = nextwidth;
    } else {
        /*
         *        Dragging all the columns to the right of this one too so
         *        update width to reflect the change
         */
        BufferWidth   += dwidth;
    }
    ef->width      = newwidth;
    if (ef < SelectEvent)
        SelectStartCol += dwidth;
    ClickCurCol   += dwidth;
    ClearMainRHS   = 1;
    InitMainMargins();

    /*
     *        Check if the drag mouse position is off the right edge of the
     *        window; if it is, then scroll the window to keep it in view.
     */
    if (ClickCurCol >= (LeftCol + BoxCols)) {
        LeftCol = ClickCurCol - BoxCols + 1;
        InitMainMargins();
    }
    if (BufferWidth != oldbufwidth || LeftCol != oldleftcol)
        UpdateMainHScroll();

    newpos1 = SelectStartCol - LeftCol - 1;
    newpos2 = SelectStartCol - LeftCol + SelectEvent->width;

    mode1 = mode2 = INVERT_FULLBOX;

    if (newpos1 == oldpos1) mode1 = INVERT_HEADER;
    if (newpos2 == oldpos2) mode2 = INVERT_HEADER;

    InvertColumn(oldpos1, mode1);
    InvertColumn(oldpos2, mode2);
    DrawHeaderLine();
    InvertColumn(newpos1, mode1);
    InvertColumn(newpos2, mode2);

    MovedColumn = 1;    /* Show we updated a column for FinishDragCol() */
}

/*
 *        MoveColumn(xpos, movetype)
 *
 *        Mini function used when dragging columns with the mouse --
 *        changes the width of the current column to pixel position xpos,
 *        as much as possible.
 *
 *        movetype is either MOVECOL_FREE or MOVECOL_FIXED -- see the
 *        description of SizeColumn() for more details.
 */
void MoveColumn(int xpos, int movetype)
{
    int colpos = LeftCol + ((xpos - BoxInLeft) / BoxCharWidth);

    if (DragEvent) {
        int disp     = colpos - ClickStartCol;
        int newwidth = DragOrigColWidth + disp;
        int dwidth   = newwidth - DragEvent->width;

        /*
         *        Now check to see if the change we're making will
         *        cause us to scroll off the left edge of the window.
         *        If it will, then reduce the change so that we scroll
         *        at a steady 1-character rate (this works out around
         *        10 chars a second, which should be fast enough).
         */
        if (LeftCol > 0 && RightCol > (BufferWidth + dwidth))
        {
            dwidth   = RightCol - BufferWidth;
            newwidth = DragEvent->width + dwidth;
        }
        if (newwidth < 1)                newwidth = 1;
        if (newwidth > MAX_FIELD_LEN)    newwidth = MAX_FIELD_LEN;

        SizeColumn(DragEvent, newwidth, movetype);
    }
}

/*
 *        FinishDragCol()
 *
 *        Finishes up a drag operation (just resets a few variables)
 */
void FinishDragCol(void)
{
    if (!DraggingColumn)
        return;

    ReportMouse(FALSE, MainWindow);
    MainWindow->IDCMPFlags &= ~IDCMP_INTUITICKS;
    MainWindow->Flags      &= ~WFLG_RMBTRAP;    /* Re-enable menus    */
    DraggingColumn = 0;

    /*
     *        We can optimise our update a bit by checking MovedColumn.
     *        This will only be true if the user actually resized one
     *        of the columns, so it saves us having to do a redraw
     *        if a column heading was accidentally clicked but not
     *        moved.
     */
    if (SelectEvent) {
        InvertColumn(SelectStartCol-LeftCol-1,                     INVERT_FULLBOX);
        InvertColumn(SelectStartCol-LeftCol+SelectEvent->width,INVERT_FULLBOX);
    }
    if (MovedColumn) {
        /*
         *        Now update the settings window and format window with the
         *        new format. This will also redraw the main window and
         *        header line for us.
         */
        BuildFormatString(BufferEFormat, BufFormat, MAX_FORM_LEN);
        InstallNewFormat(NEW_STRING);
    } else {
        /*
         *        Nothing else to update, so just redraw the header line
         *        (which will now be completely black again with no
         *        highlighted item.)
         */
        ClearMainRHS = 1;
        DrawHeaderLine();
    }
    /*
     *        Since we disable event scanning when columns are being dragged,
     *        we signal ourselves to check for new events in case any
     *        arrived while we were playing.
     */
    Signal(SysBase->ThisTask, NewEventMask);
}

/*
 *        StartDragRow(int y)
 *
 *        Starts dragging a highlight at y (pixel row) in the event output.
 *        This allows the user to use the mouse to highlight an entire line,
 *        making it easy to see all the information on the line related to
 *        the event. (This can sometimes be difficult to see in a normal
 *        window when there is a lot of white space between columns).
 *
 *        Initialises all the variables associated with this and returns
 *        with dragging enabled.
 */
void StartDragRow(int y)
{
    if (BufferEFormat[0].type == EF_END)    /* Skip empty event formats */
        return;

    SelectRow = 0;
    if (y > BoxInTop)
        SelectRow = (y - BoxInTop) / BoxSpacing;

    if (SelectRow >= BoxRows)
        SelectRow = BoxRows - 1;

    if ((TopSeq + SelectRow) > BottomSeq)
        SelectRow = BottomSeq - TopSeq;

    DraggingRow = 1;
    ReportMouse(TRUE, MainWindow);
    MainWindow->IDCMPFlags |= IDCMP_INTUITICKS;
    DrawSelectedLine(SelectRow, TRUE);
}

/*
 *        MoveToRow(y)
 *
 *        Moves the row highlight from its current position to a new position
 *        if necessary (doesn't render anything if the row position remains
 *        unchanged.)
 */
void MoveToRow(int y)
{
    int newrow = 0;

    if (y > BoxInTop)
        newrow = (y - BoxInTop) / BoxSpacing;

    if (newrow >= BoxRows)
        newrow = BoxRows - 1;

    if ((TopSeq + newrow) > BottomSeq)
        newrow = BottomSeq - TopSeq;

    if (newrow != SelectRow) {
        DrawSelectedLine(SelectRow, FALSE);
        DrawSelectedLine(newrow,    TRUE);
        SelectRow = newrow;
    }
}

/*
 *        FinishDragRow()
 *
 *        Stops highlighting the selected row and restores everything to normal
 */
void FinishDragRow(void)
{
    if (!DraggingRow)
        return;

    DrawSelectedLine(SelectRow, FALSE);
    ReportMouse(FALSE, MainWindow);
    MainWindow->IDCMPFlags &= ~IDCMP_INTUITICKS;
    DraggingRow = 0;

    /*
     *        It's possible that while we were playing with the row highlight,
     *        the entire buffer may have been swept away under our feet,
     *        leading to a slightly corrupt display (events out of sequence).
     *        We don't mind this while we're dragging the highlight, but we want
     *        to ensure it's sorted out properly afterwards. So, we do a quick
     *        check to see if the current display is no longer valid, and if so,
     *        then we redraw it. We need to handle new events first, else lots
     *        of important internal variables will be out of sync.
     */
    if (TopSeq < RealFirstSeq) {
        HandleNewEvents();
        ShowBuffer(TopSeq, DISPLAY_ALL);
    }
}

/*
 *        BeginResize()
 *
 *        Removes gadget list from window and does a few other things
 *        in preparation for a window resize occurring in the very
 *        near future.
 */
void BeginResize(void)
{
    if (!RemovedGadgets)
        RemoveGList(MainWindow, MainGadList, -1);
    RemovedGadgets = TRUE;
    if (BottomSeq >= EndSeq)
        AwaitingResize = RESIZE_BOTTOM;
    else
        AwaitingResize = RESIZE_MIDDLE;
}

/*
 *        EndResize(void)
 *
 *        Tiedies up after the window has been resized -- recalculates
 *        gadget list, refreshes display, etc.
 *
 *        Returns true for success, false for failure.
 */
int EndResize(void)
{
    if (MainWindow->Width  == CurWindowWidth &&
        MainWindow->Height == CurWindowHeight)
    {
        /*
         *        Window didn't change size after all, so don't make any
         *        changes, just restore the status quo
         */
        if (RemovedGadgets)
            AddGList(MainWindow, MainGadList, ~0, -1, NULL);
        AwaitingResize = RESIZE_DONE;
    } else {
        /*
         *        Window was resized. If necessary, reposition the buffer
         *        at the end of the new window (otherwise, if we were at
         *        the end of the buffer and the window got smaller, there
         *        would now be a few lines below the bottom of the window.)
         */
        if (AwaitingResize == RESIZE_BOTTOM)
            TopSeq = EndSeq;
        AwaitingResize = RESIZE_DONE;
        if (!RecalcMainWindow(MainWindow->Width,
                              MainWindow->Height,
                              REDRAW_GADGETS)) {
            ShowError(MSG(MSG_ERROR_RESIZE));
            return (0);
        }
        // RefreshWindowFrame(MainWindow);
    }
    RemovedGadgets = FALSE;

    /*
     *        Now, since we disabled monitoring of events during
     *        the resize, some may have accumulated that we missed.
     *        So we generate a fake new events signal to force a
     *        recheck in case anything did arrive.
     */
    Signal(SysBase->ThisTask, NewEventMask);
    return (1);
}

/*
 *        SetMainWindowWidth(int width)
 *
 *        Sets the width of the main window to the specified number of
 *        characters. Note that this call won't take effect immediately;
 *        it just tells Intuition to resize our window, which will generate
 *        a NEWSIZE event that we can trap.
 *
 *        Note: has no effect if main window isn't open.
 */
void SetMainWindowWidth(int colwidth)
{
    if (colwidth == 0)
        colwidth = BufferWidth;

    if (MainWindow) {
        int newleft      = MainWindow->LeftEdge;
        int newtop      = MainWindow->TopEdge;
        int newheight = MainWindow->Height;
        int newwidth  = MainWindow->Width - BoxWidth +
                        colwidth*BoxCharWidth + 2 * BOX_LEFT_MARGIN + 5;

        if (newwidth < MainWindow->MinWidth)
            newwidth = MainWindow->MinWidth;

        if ((newleft + newwidth) > ScreenWidth)
            newleft  = ScreenWidth - newwidth;

        if (newleft < 0) {
            newleft  = 0;
            newwidth = ScreenWidth;
        }
        /*
         *        Now check if we're so close to the edge of the screen that
         *        a single additional character space would push us over the
         *        edge .. if so, then expand the width to the full screen
         *        width, since it looks neater when the window completely
         *        fills the screen, instead of "almost" filling it.
         */
        if (newleft == 0 && (newwidth + BoxCharWidth) > ScreenWidth)
            newwidth = ScreenWidth;

        BeginResize();
        ChangeWindowBox(MainWindow, newleft, newtop, newwidth, newheight);
    }
}

/*
 *        HandleMainMsgs()
 *
 *        Processes all outstanding messages associated with the main SnoopDos
 *        window. To be called whenever we get a main window event.
 */
void HandleMainMsgs(void)
{
    static int activegad;            /* Non-zero if gadget is depressed   */
    static int activekey;            /* Keycode shortcut of activegad     */

    struct IntuiMessage *imsg;
    Settings *newsettings = NULL;
    int loadlastsaved = 0;
    int donemain = 0;
    int origtopseq;
    int updateslider;
    int changedhoriz;
    int changedvert;
    int amount;
    ULONG newval;
    int refreshtype     = CurSettings.SimpleRefresh;
    int newspacing      = BoxInterGap;
    int newstatus        = StatusLine;
    int newgadgets        = GadgetsLine;
    int newmode         = MonitorType;
    int newalign        = RightAligned;
    int dohide          = 0;

    if (!MainWindow)
        return;

    while ((imsg = GT_GetIMsg(MainWindowPort)) != NULL) {
        ULONG code  = imsg->Code;
        int shift   = imsg->Qualifier & IE_SHIFT;
        int altctrl = imsg->Qualifier & (IE_ALT | IE_CTRL);
        struct Gadget *gad;

        switch (imsg->Class) {

            case IDCMP_CLOSEWINDOW:
                if (CurSettings.Setup.HideMethod == HIDE_NONE) {
                    donemain = 1;
                    QuitFlag = 1;
                } else {
                    dohide = 1;
                }
                break;

            case IDCMP_REFRESHWINDOW:
                /*
                 *        Since the events currently displayed in our buffer
                 *        window may have scrolled off the top of the buffer
                 *        in the meantime, if we just blindly refresh, we
                 *        might end up with the refreshed portions not matching
                 *        the rest of the display. So, first try and redraw the
                 *        buffer to ensure it contains current data. Normally,
                 *        this will end up being a NOP.
                 *
                 *        See HandleNewEvents() for details as to why we need
                 *        to lock our layers first.
                 */
                DB("Begin Refresh Semapore\n");
                origtopseq = LastDrawnTopSeq;
                LOCK_LAYERS;
                ObtainSemaphore(&BufSem);
                if (TopSeq != origtopseq)
                    ShowBuffer(TopSeq, DISPLAY_ALL);
                GT_BeginRefresh(MainWindow);
                RedrawMainWindow();
                GT_EndRefresh(MainWindow, TRUE);
                DB("End refresh semaphore\n");
                ReleaseSemaphore(&BufSem);
                UNLOCK_LAYERS;
                if (TopSeq != origtopseq)
                    UpdateMainVScroll();
                break;

            case IDCMP_MENUHELP:
                /*
                 *        Display simple help for whatever menu was
                 *        active when the HELP key was pressed. To decide
                 *        which menu item to display help on, we simply
                 *        build a description string from the menu name
                 *        itself (replacing spaces with underscores and
                 *        skipping over any dots).
                 *
                 *        We also strip out sub-menu items and just show
                 *        the help for the parent item instead.
                 */
                if (code != MENUNULL) {
                    static int menunames[] = {
                        MSG_LINK_MENU_PROJECT,
                        MSG_LINK_MENU_WINDOW,
                        MSG_LINK_MENU_SETTINGS,
                        MSG_LINK_MENU_BUFFER
                    };
                    char msgname[50];
                    char *msg;
                    int menunum = MENUNUM(code);

                    if (menunum == NOMENU)
                        msg = MSG(MSG_LINK_MAINWIN);
                    else if (ITEMNUM(code) == NOITEM) {
                        msg = MSG(menunames[menunum]);
                    } else {
                        struct MenuItem *item;

                        item = ItemAddress(MainWinMenu,code | SHIFTSUB(NOSUB));
                        if (!item || !(item->Flags & ITEMTEXT)) {
                            msg = MSG(menunames[menunum]);
                        } else {
                            char *p;

                            msg = ((struct IntuiText *)item->ItemFill)->IText;
                            strcpy(msgname, "LINK Menu_");
                            p = msgname + strlen(msgname);

                            while (*msg) {
                                if (*msg == ' ' || *msg == '-')
                                    *p++ = '_';
                                else if (*msg != '.' && *msg != '?')
                                    *p++ = *msg;
                                msg++;
                            }
                            *p = '\0';
                            msg = msgname;
                        }
                    }
                    ShowAGuide(msg);
                }
                /*
                 *        It's possible the user may have played with some
                 *        menu toggles while the menu was displayed ... to
                 *        avoid us missing any items that were changed, we
                 *        simply reset them all back to the original state.
                 */
                SetMenuOptions();
                break;

            case IDCMP_MENUPICK:
                while (code != MENUNULL) {
                    struct MenuItem *item;
                    int checked;

                    item    = ItemAddress(MainWinMenu, code);
                    checked = (item->Flags & CHECKED) == CHECKED;

                    switch ((ULONG)GTMENUITEM_USERDATA(item)) {

                        case MID_OPENLOG:
                            /*
                             *        Open a new logfile
                             */
                            if (SelectFile(ChosenLogName, ChosenLogName,
                                           MainWindow, FILESEL_NEWLOGNAME))
                            {
                                if (!OpenLog(LOGMODE_PROMPT, ChosenLogName))
                                    ShowError(MSG(MSG_ERROR_STARTLOG),
                                              DefaultLogName);
                            }
                            break;

                        case MID_CLOSELOG:
                            CloseLog();
                            break;

                        case MID_PAUSE:
                            if (checked)
                                newmode = MONITOR_PAUSED;
                            else
                                newmode = MONITOR_NORMAL;
                            break;

                        case MID_DISABLE:
                            if (checked)
                                newmode = MONITOR_DISABLED;
                            else
                                newmode = MONITOR_NORMAL;
                            break;

                        case MID_STEP:
                            SingleStep();
                            newmode = MonitorType;
                            break;

                        case MID_CHANGEPRI:
                            /*
                             *        New task priority selected -- let's
                             *        read the priority directly from the
                             *        menu item itself.
                             */
                            if (checked) {
                                struct IntuiText *itext;
                                int newpri;

                                itext  = (void *)item->ItemFill;
                                newpri = atoi(itext->IText);
                                SetTaskPri(SysBase->ThisTask, newpri);
                            }
                            break;

                        case MID_HELP:
                            ShowAGuide(MSG(MSG_LINK_MAIN));
                            break;

                        case MID_ABOUT:
                            ShowError(MSG(MSG_ABOUT_SNOOPDOS), Version+6,
                                      PORT_NAME);
                            break;

                        case MID_HIDE:
                            dohide = 1;
                            break;

                        case MID_QUIT:
                            donemain = 1;
                            QuitFlag = 1;
                            break;

                        /*
                         *        Windows menu
                         */
                        case MID_SETUP:
                            if (shift && SetWindow)
                                CloseSettingsWindow();
                            else
                                OpenSettingsWindow();
                            break;

                        case MID_FUNCTION:
                            if (shift && FuncWindow)
                                CloseFunctionWindow();
                            else
                                OpenFunctionWindow();
                            break;

                        case MID_FORMAT:
                            if (shift && FormWindow)
                                CloseFormatWindow();
                            else
                                OpenFormatWindow();
                            break;

                        case MID_SETWIDTH:
                        {
                            struct IntuiText *itext = (void *)item->ItemFill;
                            int newwidth            = atoi(itext->IText);

                            SetMainWindowWidth(newwidth);
                            break;
                        }
                        case MID_ROWQUAL:
                        {
                            /*
                             *        Changing to a new row qualifier
                             */
                            int newqual = SUBNUM(code);

                            if (newqual != NOSUB)
                                RowQual = newqual;
                            break;
                        }
                        case MID_STATUS:    newstatus  = checked;    break;
                        case MID_GADGETS:    newgadgets = checked;    break;
                        case MID_AUTO_OPEN:    AutoOpen   = checked;    break;
                        case MID_DISABLE_HIDDEN: DisableOnHide = checked;break;

                        case MID_SPACE_NONE:    if (checked) newspacing  = 0;
                                                break;
                        case MID_SPACE_1P:        if (checked) newspacing  = 1;
                                                break;
                        case MID_SPACE_2P:        if (checked) newspacing  = 2;
                                                break;
                        case MID_REF_SIMPLE:    if (checked) refreshtype = 1;
                                                break;
                        case MID_REF_SMART:        if (checked) refreshtype = 0;
                                                break;
                        case MID_ALIGN_LEFT:    if (checked) newalign    = 0;
                                                break;
                        case MID_ALIGN_RIGHT:    if (checked) newalign    = 1;
                                                break;

                        /*
                         *        Settings menu
                         */
                        case MID_LOAD:
                            if (SelectFile(ConfigFileName, ConfigFileName,
                                           MainWindow, FILESEL_LOADCONFIG))
                            {
                                /*
                                 *        This new settings file will becomoe
                                 *        the last saved file, so just load
                                 *        it in at the end instead
                                 */
                                newsettings      = 0;
                                loadlastsaved = 1;
                            }
                            break;

                        case MID_SAVE:
                            if (!SaveConfig(DefaultConfigName, SAVE_NOICON))
                                ShowError(MSG(MSG_ERROR_SAVING_SETTINGS),
                                          DefaultConfigName);
                            break;

                        case MID_SAVEAS:
                            if (SelectFile(ConfigFileName, ConfigFileName,
                                           MainWindow, FILESEL_SAVECONFIG))
                            {
                                if (!SaveConfig(ConfigFileName, SAVE_ICON)) {
                                    ShowError(MSG(MSG_ERROR_SAVING_SETTINGS),
                                              ConfigFileName);
                                }
                            }
                            break;

                        case MID_RESET:
                            newsettings = &DefaultSettings;
                            break;

                        case MID_RESTORE:
                            newsettings = &RestoreSettings;
                            break;

                        case MID_LASTSAVED:
                            /*
                             *        If we successfully read in the defaults
                             *        file _or_ saved out a settings file, then
                             *        go ahead and read back in the last saved
                             *        file; otherwise, it's the very first
                             *        time we've ever been run by this user,
                             *        so just restore the factory settings
                             *        instead of producing an error message.
                             */
                            if (GotLastSaved) {
                                newsettings   = 0;
                                loadlastsaved = 1;
                            } else {
                                newsettings   = &DefaultSettings;
                            }
                            break;

                        case MID_ICONS:
                            CreateIcons    = checked;
                            break;

                        /*
                         *        Buffer menu
                         */
                        case MID_COPYWIN:
                            /*
                             *        Copy current window to clipboard
                             */
                            DisableAllWindows();
                            if (!SaveBuffer(SAVEBUF_WINDOW, SAVEBUF_CLIPBOARD,
                                            SAVEBUF_OVERWRITE))
                                ShowError(MSG(MSG_ERROR_COPY_WIN_TO_CLIP));
                            EnableAllWindows();
                            break;

                        case MID_COPYBUF:
                            /*
                             *        Copy current buffer to clipboard
                             */
                            DisableAllWindows();
                            if (!SaveBuffer(SAVEBUF_ALL, SAVEBUF_CLIPBOARD,
                                            SAVEBUF_OVERWRITE))
                                ShowError(MSG(MSG_ERROR_COPY_ALL_TO_CLIP));
                            EnableAllWindows();
                            break;

                        case MID_SAVEWIN:
                            if (SelectFile(BufferFileName, BufferFileName,
                                           MainWindow, FILESEL_SAVEWINDOW))
                            {
                                DisableAllWindows();
                                if (!SaveBuffer(SAVEBUF_WINDOW, BufferFileName,
                                                SAVEBUF_PROMPT))
                                {
                                    ShowError(MSG(MSG_ERROR_SAVING_WINDOW),
                                              BufferFileName);
                                }
                                EnableAllWindows();
                            }
                            break;

                        case MID_SAVEBUF:
                            if (SelectFile(BufferFileName, BufferFileName,
                                           MainWindow, FILESEL_SAVEBUFFER))
                            {
                                DisableAllWindows();
                                if (!SaveBuffer(SAVEBUF_ALL, BufferFileName,
                                                SAVEBUF_PROMPT))
                                {
                                    ShowError(MSG(MSG_ERROR_SAVING_BUFFER),
                                              BufferFileName);
                                }
                                EnableAllWindows();
                            }
                            break;

                        case MID_CLEARBUF:
                            ClearWindowBuffer();
                            break;

                    }
                    code = item->NextSelect;
                }
                break;

            case IDCMP_IDCMPUPDATE:
                /*
                 *        Handle BOOPSI slider movement. BOOPSI arrow
                 *        gadgets are no longer handled here but are
                 *        treated as ordinary button gadgets since
                 *        otherwise, we can't get the desired behaviour
                 *        (with a delay after the first click before it
                 *        starts repeating).
                 */
                changedhoriz = 0;
                changedvert  = 0;
                updateslider = 0;

                GetAttr(PGA_Top, Gadget[GID_HSCROLLER], &newval);
                if (newval != LeftCol)
                    ScrollHorizontal(newval - LeftCol);

                GetAttr(PGA_Top, Gadget[GID_VSCROLLER], &newval);
                if (newval != (TopSeq - FirstSeq)) {
                    ShowBuffer(FirstSeq + newval, DISPLAY_QUICK);
                    CheckForDirtyMainWindow();
                }
                break;

            case IDCMP_INTUITICKS:
                if (ScrollDirection) {
                    /*
                     *        Handle possible arrow gadget scrolling
                     */
                    if (ScrollCount >= 3) {
                        if (Gadget[ScrollDirection]->Flags & GFLG_SELECTED)
                            DoArrowScrolling(ScrollDirection, 1);
                    } else {
                        ScrollCount++;
                    }
                }
                if (DraggingColumn) {
                    /*
                     *        Handle horizontal scrolling to left or right;
                     *        we just treat it as a normal mouse move -- in
                     *        the general case, the displacement will be
                     *        zero, so no updating will take place.
                     */
                    MoveColumn(imsg->MouseX,
                               shift ? MOVECOL_FIXED : MOVECOL_FREE);
                }
                if (DraggingRow) {
                    /*
                     *        Dragging a highlight across rows, so we want to
                     *        automatically scroll if we are off the top or
                     *        bottom of the window. We also check to make sure
                     *        we're not off the top or bottom of the buffer
                     *        (no harm would come if we were, but it would
                     *        lead to unnecessary flashing of the display
                     *        highlight)
                     */
                    int scrolldir = 0;

                    if (imsg->MouseY < BoxInTop && TopSeq > FirstSeq)
                    {
                        scrolldir = GID_UPARROW;
                    } else if (imsg->MouseY > (BoxInTop + BoxInHeight) &&
                               BottomSeq    < EndSeq)
                    {
                        scrolldir = GID_DOWNARROW;
                    }
                    if (scrolldir) {
                        FinishDragRow();
                        DoArrowScrolling(scrolldir, 1);
                        StartDragRow(imsg->MouseY);
                    }
                }
                break;

            case IDCMP_MOUSEBUTTONS:
            {
                static int lastrmb;

                int lmb = imsg->Qualifier & IEQUALIFIER_LEFTBUTTON;
                int rmb = imsg->Qualifier & IEQUALIFIER_RBUTTON;

                if (lmb && !rmb && !lastrmb) {
                    static WORD lastx, lasty;
                    static ULONG lastsecs, lastmicros;
                    int curx = imsg->MouseX;
                    int cury = imsg->MouseY;

                    if (curx >= (lastx - 1) && curx <= (lastx + 1) &&
                        cury >= (lasty - 1) && cury <= (lasty + 1))
                    {
                        if (DoubleClick(lastsecs, lastmicros,
                                        imsg->Seconds, imsg->Micros)) {
                            /*
                             *        Got a double-click. Now check if it's
                             *        in the window header area. If so,
                             *        open or close the format window.
                             */
                            if (cury < BoxTop) {
                                if (shift && FormWindow)
                                    CloseFormatWindow();
                                else
                                    OpenFormatWindow();
                                break;
                            }
                        }
                    }
                    lastx        = curx;
                    lasty        = cury;
                    lastsecs    = imsg->Seconds;
                    lastmicros    = imsg->Micros;
                }
                if (DraggingColumn) {
                    if (lmb == 0) {
                        /*
                         *        We've finished dragging our column
                         */
                        FinishDragCol();
                    } else if (rmb) {
                        /*
                         *        User clicked right button to cancel the
                         *        drag operation, so restore column width
                         *        to its original position and cancel drag.
                         */
cancel_dragging_column:
                        /* Stop highlight flash when restoring orig header */


                        if (DraggingColumn) {
                            EventFormat *nextev = DragEvent + 1;

                            /*
                             *        We invert the columns now and then
                             *        set SelectEvent to NULL to let
                             *        FinishDragCol() know we have already
                             *        unhighlighted them (this is because
                             *        we're hacking the window format
                             *        directly).
                             */
                            InvertColumn(SelectStartCol - LeftCol - 1,
                                         INVERT_FULLBOX);
                            InvertColumn(SelectStartCol - LeftCol +
                                         SelectEvent->width, INVERT_FULLBOX);
                            SelectEvent = NULL;
                            DragEvent->width = DragOrigColWidth;
                            if (nextev->type != EF_END)
                                nextev->width = NextOrigColWidth;
                            BufferWidth = OrigBufWidth;
                            if (LeftCol != OrigLeftCol) {
                                LeftCol = OrigLeftCol;
                                InitMainMargins();
                                UpdateMainHScroll();
                            }
                            FinishDragCol();
                        }
                        lastrmb = 1;
                        break;
                    }
                } else if (lmb && !lastrmb) {
                    /*
                     *        Could be starting to drag a new column or row!
                     *        Check bounds to see if we are. If lastrmb was
                     *        true, then user has just released right mouse
                     *        button but hasn't yet released left mouse button,
                     *        so we ignore this attempt..
                     */
                    int x = imsg->MouseX;
                    int y = imsg->MouseY;

                    if (y < BoxTop && x >= BoxInLeft &&
                                      x < (BoxInLeft + BoxInWidth)) {
                        StartDragCol(x);
                    } else if (y > BoxInTop && y < (BoxInTop + BoxInHeight)) {
                        /*
                         *        Now check if correct qualifier is held down
                         *        to activate the row selection. We need to use
                         *        a slighty tricky boolean equation to handle
                         *        ROWQUAL_NONE, wher
                         */
                        int qual = imsg->Qualifier & IE_ALL;

                        if (RowQual == ROWQUAL_ANY                             ||
                            (RowQual == ROWQUAL_NONE && !qual)                 ||
                            (qual && (qual & RowQualTable[RowQual]) == qual))
                        {
                            StartDragRow(y);
                        }
                    }
                }
                if (DraggingRow && !lmb)
                    FinishDragRow();

                lastrmb = rmb;
                break;
            }

            case IDCMP_MOUSEMOVE:
                if (DraggingColumn) {
                    MoveColumn(imsg->MouseX,
                               shift ? MOVECOL_FIXED : MOVECOL_FREE);
                }
                if (DraggingRow)
                    MoveToRow(imsg->MouseY);
                break;

            case IDCMP_GADGETUP:
            case IDCMP_GADGETDOWN:
                gad   = (struct Gadget *)imsg->IAddress;

handle_maingadgets:
                switch (gad->GadgetID) {
                    case GID_UPARROW:
                    case GID_DOWNARROW:
                    case GID_LEFTARROW:
                    case GID_RIGHTARROW:
                        if (imsg->Class == IDCMP_GADGETDOWN) {
                            /*
                             *        User clicked on a scroll button so
                             *        kick-off the scrolling.
                             */
                            ScrollDirection = gad->GadgetID;
                            DoArrowScrolling(ScrollDirection, 1);
                            MainWindow->IDCMPFlags |= IDCMP_INTUITICKS;
                            ScrollCount = 0;
                        } else {
                            /*
                             *        User let go of a scroll button so turn
                             *        off scrolling.
                             */
                            ScrollDirection = 0;
                            MainWindow->IDCMPFlags &= ~IDCMP_INTUITICKS;
                        }
                        break;

                    case GID_SETUP:
                        if (shift && SetWindow)
                            CloseSettingsWindow();
                        else
                            OpenSettingsWindow();
                        break;

                    case GID_FUNCTION:
                        if (shift && FuncWindow)
                            CloseFunctionWindow();
                        else
                            OpenFunctionWindow();
                        break;

                    case GID_SAVESET:
                        /*
                         *        Save settings to configuration file
                         */
                        ShowStatus(MSG(MSG_STATUS_SAVESET));
                        DisableAllWindows();
                        if (!SaveConfig(DefaultConfigName, SAVE_NOICON))
                            ShowError(MSG(MSG_ERROR_SAVING_SETTINGS),
                                      DefaultConfigName);
                        EnableAllWindows();
                        UpdateStatus();
                        break;

                    case GID_PAUSE:
                        if (gad->Flags & GFLG_SELECTED)
                            newmode = MONITOR_PAUSED;
                        else
                            newmode = MONITOR_NORMAL;
                        break;

                    case GID_DISABLE:
                        if (gad->Flags & GFLG_SELECTED)
                            newmode = MONITOR_DISABLED;
                        else
                            newmode = MONITOR_NORMAL;
                        break;

                    case GID_APPENDLOG:
                    case GID_STARTLOG:
                    case GID_SERIALLOG:
                        if (!OpenLog(DefaultLogMode, DefaultLogName))
                            ShowError(MSG(MSG_ERROR_STARTLOG), DefaultLogName);
                        break;

                    case GID_OPENLOG:
#if 0
                        /*
                         *        Quick and dirty benchmark code to scroll
                         *        the buffer 10 times to check speed
                         */
                        { int i, l;

                          for (i = 0; i < 10; i++)
                            for (l = FirstSeq; l < EndSeq; l += BoxRows)
                              ShowBuffer(l, DISPLAY_QUICK);
                          break;
                        }
#endif
                        /*
                         *        Back to normal: open a new log file
                         */
                        if (SelectFile(ChosenLogName, ChosenLogName,
                                       MainWindow, FILESEL_NEWLOGNAME))
                        {
                            OpenLog(LOGMODE_PROMPT, ChosenLogName);
                        }
                        break;

                    case GID_CLOSELOG:
                        CloseLog();
                        break;

                    case GID_HIDE:
                        dohide = 1;
                        break;

                    case GID_QUIT:
                        donemain = 1;
                        QuitFlag = 1;
                        break;
                }
                break;

            case IDCMP_SIZEVERIFY:
                BeginResize();
                break;

            case IDCMP_CHANGEWINDOW:
            case IDCMP_NEWSIZE:
                if (!EndResize())
                    donemain = 1;
                break;

            case IDCMP_INACTIVEWINDOW:
                /*
                 *        If window becomes inactive, cancel any column
                 *        drag currently in operation, since it could
                 *        confuse things otherwise when the window is
                 *        later re-activated.
                 */
                if (activegad) {
                    ShowGadget(MainWindow, Gadget[activegad], GADGET_UP);
                    activegad = 0;
                }
                if (DraggingRow)
                    FinishDragRow();

                if (DraggingColumn)
                    goto cancel_dragging_column;
                break;

            case IDCMP_RAWKEY:
            {
                /*
                 *        Handle all keyboard shortcuts
                 */
                int upstroke = imsg->Code & 0x80;
                int keypress = ConvertIMsgToChar(imsg);
                UBYTE gadid  = MainKeyboard[keypress];

                if (activegad) {
                    /*
                     *        We're releasing a gadget that was pressed
                     *        earlier, so handle it now
                     */
                    int samekey = (imsg->Code & 0x7f) == activekey;

                    if (samekey && !upstroke)    /* Ignore repeated keys */
                        break;

                    ShowGadget(MainWindow, Gadget[activegad], GADGET_UP);
                    if (samekey) {
                        /*
                         *        Just released the key that was originally
                         *        pressed for this gadget, so now go and
                         *        handle the gadget action.
                         */
                        gadid     = activegad;
                        gad       = Gadget[gadid];
                        activegad = 0;
                        goto handle_maingadgets;
                    }
                    /*
                     *        If the above check didn't kick in, it means
                     *        we got a downpress of a different key, so
                     *        disable the gadget for this key and continue
                     *        to press the other key.
                     */
                    activegad = 0;
                }

                /*
                 *        Handle simple keyboard input (i.e. vanilla keys)
                 *
                 *        In addition to the gadget shortcuts in MainKeyboard[]
                 *        we also use TAB to unconditionally pause, and Space/
                 *        Return to singlestep if we're already paused.
                 *
                 *        (If we made Space always single step, then if someone
                 *        hit it by accident when the SnoopDos window was open,
                 *        it would go into pause mode which would be annoying.)
                 */
                if (gadid) {
                    /*
                     *        Handle a gadget shortcut
                     */
                    gad = Gadget[gadid];
                    if (gadid == GID_PAUSE || gadid == GID_DISABLE) {
                        /*
                         *        PAUSE and DISABLE are toggle gadgets
                         *        which will highlight in the gadget code.
                         *        So, we handle them immediately, to give
                         *        instant feedback.
                         */
                        gad->Flags ^= GFLG_SELECTED;
                        goto handle_maingadgets;
                    } else {
                        /*
                         *        Now a slight problem ... since our logfile
                         *        gadget can cycle between multiple values,
                         *        we had better make sure that the same
                         *        shortcut will activate whichever one is
                         *        currently displayed rather than the
                         *        default hotkey (since all three opens
                         *        may share the same hotkey). If the logfile
                         *        is already open, we do nothing.
                         */
                        if (gadid == GID_OPENLOG  || gadid == GID_APPENDLOG ||
                            gadid == GID_STARTLOG || gadid == GID_SERIALLOG)
                        {
                            if (LogActive)
                                break;

                            gadid = LogButtonID;
                            gad   = Gadget[gadid];
                        }

                        /*
                         *        All these gadget are button gadgets so we
                         *        just highlight them now, and set the
                         *        activegad flag -- on the upstroke, they'll
                         *        be released.
                         */
                        ShowGadget(MainWindow, gad, GADGET_DOWN);
                        activegad = gadid;
                        activekey = imsg->Code;
                    }
                    break;
                }

                /*
                 *        Didn't match one of the gadget hotkeys,
                 *        now check for some other special keys
                 */
                switch (keypress) {
                    case 0x0D:        /* Return */
                        DoArrowScrolling(GID_DOWNARROW, 1);
                        break;

                    case ' ':        /* Space */
                        if (DraggingColumn) {
                            /*
                             *        Redraw window with current format
                             *        to date so user can see how it looks
                             */
                            InvertColumn(SelectStartCol - LeftCol - 1,
                                         INVERT_FULLBOX);
                            InvertColumn(SelectStartCol - LeftCol +
                                         SelectEvent->width, INVERT_FULLBOX);
                            BuildFormatString(BufferEFormat,
                                              BufFormat, MAX_FORM_LEN);
                            InstallNewFormat(NEW_STRING);
                            InvertColumn(SelectStartCol - LeftCol - 1,
                                         INVERT_FULLBOX);
                            InvertColumn(SelectStartCol - LeftCol +
                                         SelectEvent->width, INVERT_FULLBOX);
                        } else if (MonitorType == MONITOR_PAUSED) {
                            /*
                             *        Singlestep, but only if we were
                             *        already paused.
                             */
                            SingleStep();
                            newmode = MonitorType;
                        }
                        break;

                    case 0x09:        /* Tab */
                        SingleStep();
                        newmode = MonitorType;
                        break;

                    case 0x03:        /* CTRL-C -- quit        */
                        gadid = GID_QUIT;
                        ShowGadget(MainWindow, Gadget[gadid], GADGET_DOWN);
                        activegad = gadid;
                        activekey = imsg->Code;
                        break;

                    case 0x04:        /* CTRL-D -- disable    */
                        newmode = MONITOR_DISABLED;
                        break;

                    case 0x05:        /* CTRL-E -- enable        */
                        newmode = MONITOR_NORMAL;
                        break;

                    case 0x06:        /* CTRL-F -- to front    */
                        OpenMainWindow();
                        break;

                    case '\033':    /* ESC -- cancel column drag */
                        if (DraggingColumn)
                            goto cancel_dragging_column;
                        break;
                }

                /*
                 *        Finally, finally, we do a quick check to see
                 *        if the keystroke matches the format editor
                 *        menu shortcut; if it does, we open the format
                 *        editor. (If this key has been used by one of
                 *        the other gadgets, e.g. due to localisation,
                 *        then we will never get here, so not a problem.)
                 *
                 *        As with the settings and functions windows, if
                 *        the keypress is shifted, then we close the
                 *        window if it was already open.
                 */
                if ((keypress & 0x5F) == (*MSG(MSG_WINDOWS_FORMAT) & 0x5F)) {
                    if (shift && FormWindow)
                        CloseFormatWindow();
                    else
                        OpenFormatWindow();
                    break;
                }

                /*
                 *        Handle cursor keys etc. We allow scrolling by
                 *        varying numbers of steps, depending on the
                 *        qualifier key used.
                 */
                amount  = 1;
                switch (imsg->Code) {
                    case CURSORUP:
                        if (shift)   amount = BoxRows;
                        if (altctrl) amount = TopSeq - FirstSeq;
                        DoArrowScrolling(GID_UPARROW, amount);
                        break;

                    case CURSORDOWN:
                        if (shift)   amount = BoxRows;
                        if (altctrl) amount = EndSeq - TopSeq;
                        DoArrowScrolling(GID_DOWNARROW, amount);
                        break;

                    case CURSORLEFT:
                        if (shift)   amount = HSCROLL_SHIFT_JUMP;
                        if (altctrl) amount = LeftCol;
                        DoArrowScrolling(GID_LEFTARROW, amount);
                        break;

                    case CURSORRIGHT:
                        if (shift)   amount = HSCROLL_SHIFT_JUMP;
                        if (altctrl) amount = BufferWidth - LeftCol;
                        DoArrowScrolling(GID_RIGHTARROW, amount);
                        break;

                    case TABKEY:
                        if (shift)
                            newmode = MONITOR_NORMAL;
                        break;

                    case HELPKEY:
                        ShowAGuide(MSG(MSG_LINK_MAINWIN));
                        break;
                }
                break;
            }
        }
        GT_ReplyIMsg(imsg);
    }
    if (newmode != MonitorType)
        SetMonitorMode(newmode);

    if (dohide)
        HideSnoopDos();
    else if (donemain)
        CloseMainWindow();
    else if (refreshtype != CurSettings.SimpleRefresh) {
        BoxInterGap = newspacing;
        StatusLine  = newstatus;
        GadgetsLine = newgadgets;
        CurSettings.SimpleRefresh = refreshtype;
        ReOpenMainWindow();
    } else if (newsettings) {
        InstallSettings(newsettings, SET_ALL);
    } else if (loadlastsaved) {
        /*
         *        We read the last-saved configuration from a file rather
         *        than just from a memory copy so that the user can edit
         *        the disk version by hand first if they so choose
         */
        if (!LoadConfig(ConfigFileName, MODE_INTERNAL, NULL))
            ShowError(MSG(MSG_ERROR_LOADING_SETTINGS), ConfigFileName);
    } else {
        if (newspacing != BoxInterGap)
            SetTextSpacing(newspacing);
        else if (newalign != RightAligned) {
            RightAligned = newalign;
            ShowBuffer(TopSeq, DISPLAY_ALL);
        }
        if (newgadgets != GadgetsLine || newstatus != StatusLine) {
            StatusLine  = newstatus;
            GadgetsLine = newgadgets;

            if (!RecalcMainWindow(MainWindow->Width, MainWindow->Height,
                                  REDRAW_GADGETS))
                ShowError(MSG(MSG_ERROR_RESIZE));
        }
    }
}

/*
 *        DrawSelectedLine(row, highlight)
 *
 *        Calculates what event is currently positioned at the specified row
 *        in the main window and redraws that row either highlighted or
 *        unhighlighted. If the event is now complete, its state is updated
 *        accordingly. If no event can be found at that line, then the nearest
 *        row is highlighted instead.
 *
 *        If highlight is true, the row is highlighted, else it is unhighlighted.
 */
void DrawSelectedLine(int row, int highlight)
{
    struct RastPort *rport = MainWindow->RPort;
    Event *ev;
    Event *firstevent;
    int   firstseq;
    int   fillpen = 0;
    int   textpen = 1;
    int   i;

    if (IsListEmpty(&EventList) || BufferEFormat[0].type == EF_END)
        return;

    /*
     *        First, find the event
     */
    LOCK_LAYERS;
    ObtainSemaphore(&BufSem);
    firstevent = HeadNode(&EventList);
    firstseq   = firstevent->seqnum;
    ev         = TopEvent;
    if (TopSeq < firstseq)
        ev = firstevent;

    for (i = 0; i < row && ev != TailNode(&EventList); i++, ev = NextNode(ev))
        ;
    if (ev->status == ES_READY)
        ev->status = ES_ACCEPTED;

    FormatEvent(BufferEFormat, ev, BufferLine, LeftCol, LeftCol + BoxCols - 1);
    /*
     *        Now setup rastport according to whether or not we want it
     *        highlighted
     */
    if (highlight) {
        fillpen = ScreenDI->dri_Pens[FILLPEN];
        textpen = ScreenDI->dri_Pens[FILLTEXTPEN];
    }
    SetAPen(rport, textpen);
    SetBPen(rport, fillpen);
    SetDrMd(rport, JAM2);
    Move(rport, BoxInLeft, BoxBaseline + i * BoxSpacing);
    Text(rport, BufferLine, BoxCols);
    ReleaseSemaphore(&BufSem);
    UNLOCK_LAYERS;
}

/*
 *        OutputBufLine(event, row)
 *
 *        Outputs the specified event to the buffer display at the given
 *        row, using the current format, left and right col indicators.
 *        See also DrawSelectedLine() above.
 */
void OutputBufLine(Event *event, int row)
{
    struct RastPort *rport = MainWindow->RPort;

    if (event->status == ES_READY)
        event->status = ES_ACCEPTED;

    FormatEvent(BufferEFormat, event, BufferLine, LeftCol, RightCol);
    Move(rport, BoxInLeft, BoxBaseline + row*BoxSpacing);
    Text(rport, BufferLine, RightCol - LeftCol + 1);
}

/*
 *        ClearWindowBuffer()
 *
 *        Clears the buffer area on the screen, and empties the internal
 *        buffer as well (called by the Clear Buffer menu option).
 */
void ClearWindowBuffer(void)
{
    ClearBuffer();
    if (MainWindow) {
        struct RastPort *rport = MainWindow->RPort;

        /*
         *        Erase strip to right of our rendered text
         */
        SetAPen(rport, 0);
        SetDrMd(rport, JAM1);
        RectFill(rport, BoxInLeft, BoxInTop,
                        BoxInLeft+BoxInWidth-1, BoxInTop+BoxInHeight-1);

        UpdateMainVScroll();
    }
    ClearMainRHS = 0;
}

/*
 *        ShowBuffer(seqnum, displaytype)
 *
 *        Adjusts the buffer display so that it begins at event numbered
 *        seqnum. If more than half of the needed events are currently
 *        on display, the buffer is scrolled to put them in the correct
 *        position. Any lines not currently on display are redrawn.
 *
 *        Updates TopSeq and BottomSeq accordingly.
 *
 *        Also does validity checking to ensure that if our current set of
 *        events has scrolled off the top of the buffer, we will still be
 *        displayed.
 *
 *        Displaytype is DISPLAY_ALL or DISPLAY_QUICK, to force either
 *        the entire buffer to be redrawn dumbly at the new position, or
 *        to optimise it by scrolling, only drawing changed items, etc.
 *
 *        If displaytype is DISPLAY_NONE, then all the Seq variables are
 *        recalculated to take account of events scrolling off the top
 *        etc. but no new output is displayed. This allows us to update
 *        the scrollbar without interrupting the current screen display
 *        while the user is reading it.
 *
 *        Note: it is save to call ShowBuffer with DISPLAY_NONE when the
 *        main window is closed, but for all the others, it should be open.
 */
void ShowBuffer(LONG seqnum, int displaytype)
{
    struct RastPort *rport;
    LONG  oldtopseq = TopSeq;        /* Saved old top position                */
    LONG  firstseq;                    /* First sequence number on list        */
    Event *firstevent;                /* First event on list                    */
    Event *topev;                    /* New top event displayed on screen    */
    int   row = 0;                    /* Current output row in buffer            */
    int   scrollthresh;                /* If moving less than this, use scroll    */

    /*
     *        If there is a lot of activity, then sometimes we can get
     *        output messages in between an IDCMP_VERIFY and an IDCMP_NEWSIZE
     *        which can lead to screen artefacts appearing in the border.
     *        One way to avoid these is to always refresh the borders when
     *        we get an IDCMP_NEWSIZE, but a neater way is to suspend output
     *        while we're between the two types of message -- this is less
     *        visually jarring on the user.
     */
    if (AwaitingResize != RESIZE_DONE)
        displaytype = DISPLAY_NONE;

    /*
     *        Important that we lock our layers -- see HandleNewEvents()
     *        for a more detailed explanation of why.
     */
    DB("ShowBuffer-Semaphore\n");
    LOCK_LAYERS;
    ObtainSemaphore(&BufSem);

    if (IsListEmpty(&EventList) ||
                    ((Event *)HeadNode(&EventList))->status == ES_CREATING)
        goto done_show_buffer;

    firstevent = HeadNode(&EventList);
    firstseq   = firstevent->seqnum;

    if (TopSeq < firstseq) {
        TopEvent    = firstevent;
        TopSeq      = firstseq;
        BottomSeq   = firstseq;
        /*
         *        The events currently on display in the window must have
         *        scrolled off the top of the buffer, so we can't assume
         *        any of them still exist. So, force a full redraw instead.
         */
        if (displaytype == DISPLAY_QUICK)
            displaytype = DISPLAY_ALL;
    }
    if (EndSeq < firstseq) {
        EndSeq      = firstseq;
        EndEvent    = firstevent;
    }
    if (seqnum < firstseq)    seqnum = firstseq;
    if (seqnum > EndSeq)    seqnum = EndSeq;

    /*
     *        Work out if we need to scan forwards or backwards from the
     *        current event at the top of the screen
     */
    if (seqnum <= TopSeq) {
        /*
         *        Scanning backwards from current top of screen. Now see if
         *        it would be faster to scan forward from the start of the
         *        list.
         */
        if ((TopSeq - seqnum) < (seqnum - firstseq)) {
            for (topev = TopEvent;
                     topev != HeadNode(&EventList) && topev->seqnum > seqnum;
                     topev = PrevNode(topev))
                ;
        } else {
            for (topev = firstevent;
                    topev != TailNode(&EventList) && topev->seqnum < seqnum;
                     topev = NextNode(topev))
                ;
        }
    } else { /* seqnum > TopSeq */
        /*
         *        Scanning forwards from the current top of the screen. Now
         *        see if it would be faster to scan backwards from the end of
         *        the event list.
         */
        if ((EndSeq - seqnum) < (seqnum - TopSeq)) {
            for (topev = EndEvent; topev != TopEvent && topev->seqnum > seqnum;
                                   topev = PrevNode(topev))
                ;
        } else {
            for (topev = TopEvent; topev != EndEvent && topev->seqnum < seqnum;
                                   topev = NextNode(topev))
                ;
        }
    }

    /*
     *        Now topev is the new top event to display in the window.
     *        But wait! What if this topev is close to the bottom of our
     *        list? We want to always show a full window of text if
     *        possible. So, adjust it to ensure as many events as possible
     *        can fit in the screen.
     */
    while (topev != firstevent && seqnum > (EndSeq - BoxRows + 1)) {
        topev = PrevNode(topev);
        seqnum--;
    }

    /*
     *        Okay! Now we finally have topev pointing to our new top of
     *        screen node. Now update our display accordingly. We also
     *        take this opportunity to refresh our scroll bar, since it's
     *        relative position may well now be different.
     */
    FirstSeq  = firstseq;
    TopEvent  = topev;
    TopSeq    = seqnum;

    if ((displaytype & DISPLAY_NONE) || !MainWindow)
        goto done_show_buffer;

    SetupBufferRastPort();
    rport = MainWindow->RPort;

    /*
     *        We record the top line that was last drawn into the buffer. This
     *        is useful when ShowBuffer(..., DISPLAY_NONE) is called since it
     *        let's us detect when the info inside the window is no longer valid
     *        due to having scrolled off the top of the buffer.
     */
    if (seqnum != oldtopseq)
        LastDrawnTopSeq = TopSeq;

    if (displaytype & DISPLAY_ALL)
        goto redrawall;

    /*
     *        Setup so we only render to bitplane 0 -- this greatly
     *        speeds up text output and rendering speed, especially
     *        on deep Workbenches.
     */
    if (GfxBase->LibNode.lib_Version >= 39)
        SetWriteMask(rport, 1);        /* Speed up scrolling and rendering! */
    else
        rport->Mask = 1;

    /*
     *        Now setup our scroll threshold. If running on V37 (where
     *        when we scroll, we get backfilled with colour 0 before
     *        we can redraw), then our threshold is 1/2 the displayed
     *        number of rows. If running on V39 or above, we increase
     *        the threshold to 3/4 of the displayed rows.
     */
    scrollthresh = BoxRows / 2;
    if (GfxBase->LibNode.lib_Version >= 39)
        scrollthresh = (BoxRows * 3) / 4;

    if (seqnum == oldtopseq) {
        /*
         *        We're already at the correct position in the buffer, so
         *        just scan looking for new or updated entries (i.e. any
         *        which are not yet ES_ACCEPTED)
         */
        while (row < BoxRows && seqnum <= EndSeq) {
            if (topev->status != ES_ACCEPTED)
                OutputBufLine(topev, row);
            topev = NextNode(topev);
            seqnum++;
            row++;
        }
    } else if (seqnum > oldtopseq && (seqnum - oldtopseq) <= scrollthresh) {
        /*
         *        Scrolling forward, so move buffer up.
         *
         *        If running on V39 or above, we disable background fills
         *        for our layer while we ScrollRaster() since we're going
         *        to be redrawing the area anyway -- it speeds things up,
         *        and is also less visually obtrusive.
         */
        int dy = seqnum - oldtopseq;
        int scrollwidth = (RightCol - LeftCol + 1) * BoxCharWidth;

        DB("ScrollRaster start\n");
        if (GfxBase->LibNode.lib_Version >= 39) {
            struct Hook *oldhook;

            oldhook = InstallLayerHook(MainWindow->WLayer, LAYERS_NOBACKFILL);
            ScrollRasterBF(rport, 0, dy * BoxSpacing,
                           BoxInLeft, BoxInTop,
                           BoxInLeft + scrollwidth-1, BoxInTop + BoxInHeight-1);
            InstallLayerHook(MainWindow->WLayer, oldhook);
        } else {
            ScrollRaster(rport, 0, dy * BoxSpacing,
                         BoxInLeft, BoxInTop,
                         BoxInLeft + scrollwidth-1, BoxInTop + BoxInHeight-1);
        }
        DB("ScrollRaster end\n");

        while (seqnum <= EndSeq && row < (BoxRows - dy)) {
            /*
             *        Even though these lines are already present,
             *        we still have to re-output any lines that are
             *        not ES_ACCEPTED since they may have been
             *        updated since the last time they were displayed.
             */
            if (topev->status != ES_ACCEPTED)
                OutputBufLine(topev, row);
            topev = NextNode(topev);
            seqnum++;
            row++;
        }
        while (seqnum <= EndSeq && row < BoxRows) {
            OutputBufLine(topev, row);
            topev = NextNode(topev);
            seqnum++;
            row++;
        }
    } else if (oldtopseq > seqnum && (oldtopseq - seqnum) <= scrollthresh) {
        /*
         *        Scrolling backward, so move buffer down.
         */
        int dy = oldtopseq - seqnum;
        int scrollwidth = (RightCol - LeftCol + 1) * BoxCharWidth;

        DB("ScrollRaster start\n");
        if (GfxBase->LibNode.lib_Version >= 39) {
            struct Hook *oldhook;

            oldhook = InstallLayerHook(MainWindow->WLayer, LAYERS_NOBACKFILL);
            ScrollRasterBF(rport, 0, -dy * BoxSpacing,
                           BoxInLeft, BoxInTop,
                           BoxInLeft + scrollwidth-1, BoxInTop+BoxInHeight-1);
            InstallLayerHook(MainWindow->WLayer, oldhook);
        } else {
            ScrollRaster(rport, 0, -dy * BoxSpacing,
                         BoxInLeft, BoxInTop,
                         BoxInLeft + scrollwidth-1, BoxInTop + BoxInHeight-1);
        }
        DB("ScrollRaster end\n");
        /*
         *        Update the new (blank) areas first
         */
        while (seqnum <= oldtopseq) {
            OutputBufLine(topev, row);
            topev = NextNode(topev);
            seqnum++;
            row++;
        }
        /*
         *        Now can the remaining lines in the buffer (which are
         *        already on the screen) and re-output any which are
         *        not ES_ACCEPTED, since they may have changed since the
         *        last update.
         */
        while (row < BoxRows && seqnum <= EndSeq) {
            if (topev->status != ES_ACCEPTED)
                OutputBufLine(topev, row);
            topev = NextNode(topev);
            seqnum++;
            row++;
        }
    } else {
        /*
         *        The move is too big to handle by scrolling, so just
         *        redraw the entire buffer instead.
         */
redrawall:
        while (row < BoxRows && seqnum <= EndSeq) {
            OutputBufLine(topev, row);
            topev = NextNode(topev);
            seqnum++;
            row++;
        }
    }

    if ((displaytype & DISPLAY_ALL) == 0) {
        /*
         *        Undo the bitplane optimisation we did earlier, but only
         *        if we're doing an optimised refresh.
         */
        if (GfxBase->LibNode.lib_Version >= 39)
            SetWriteMask(rport, 0xFF);
        else
            rport->Mask = 0xff;
    }
    BottomSeq = seqnum - 1;    /* Bottom most sequence number in window */

done_show_buffer:
    DB("ShowBuffer-Semaphore-done\n");
    ReleaseSemaphore(&BufSem);
    UNLOCK_LAYERS;
}

/*
 *        HandleNewEvents()
 *
 *        Called whenever we are signalled that a new event has arrived
 *        in the input queue.
 *
 *        We simply scan the queue from our last known position to our
 *        current position and, if necessary, update our output window
 *        to reflect any new events. We also output any new _complete_
 *        events to the logfile.
 */
void HandleNewEvents(void)
{
    Event *firstevent;
    Event *newev;
    Event *ev;
    int   curendcompleteseq = EndCompleteSeq;
    int   curendseq         = EndSeq;
    LONG  newseq;
    int   refresh = 0;

    DB("HandleNewEvent-Semaphore\n");

    if (IsListEmpty(&EventList) || AwaitingResize != RESIZE_DONE
                                || DraggingColumn || DraggingRow)
        return;

    /*
     *        It is vital that for the duration of the screen update,
     *        we retain complete access to our output rastport. Otherwise,
     *        we can run into a deadlock where a higher priority task
     *        (like input.device) locks the screen layer's while we
     *        are in the middle of our refresh, and then calls one of
     *        our patched functions (like OpenFont) -- instant hang
     *        (because we own the buffer semaphore and the patched
     *        function will sit waiting for us to free it).
     *
     *        By locking our layers, we ensure that nobody else can
     *        ever get in once we start our refresh. The downside is
     *        that this locks out menu rendering etc, but since we'll
     *        be quick at refreshing, that's okay.
     *
     *        Note that we lock the layers _before_ getting the buffer
     *        semaphore -- if we do it afterwards, there is a window of
     *        opportunity where we task switch to a higher priority task
     *        between the two calls which then proceeds to lock layers
     *        and try and lock the buffer semaphore -- deadlock again!
     *
     *        News Flash! We don't lock layers any more, since it lead
     *        to jerky performance when dragging the scrollbar etc.
     *        Instead, our patch code checks to see if our layers are
     *        locked by the calling task and if they are, bypasses
     *        outputting the event completely. Since the only things
     *        that ever call our patches when layers are locked are
     *        low-level Intuition functions that are re-rendering
     *        gadgets etc (and calling OpenFont()) this is actually
     *        a win-win since we're typically not interested in those
     *        events anyway.
     */
    if (MainWindow) {
        LOCK_LAYERS;        /* This is now a no-op */
    }
    ObtainSemaphore(&BufSem);

    if (EndSeq == BottomSeq)             /* If at end of buf, show new o/p    */
        refresh = 1;

    firstevent = HeadNode(&EventList);
    if (firstevent->seqnum > EndCompleteSeq)
        newev = firstevent;
    else if (EndCompleteEvent == TailNode(&EventList)) {
        newev = EndCompleteEvent;
    } else {
        newev = NextNode(EndCompleteEvent);
    }
    newseq = newev->seqnum;

    /*
     *        First we scan all the new incoming entries to figure out
     *        our new EndEvent/EndSeq (for ShowBuffer)
     */
    for (ev = newev; NextNode(ev) != NULL && ev->status != ES_CREATING;
                     ev = NextNode(ev))
        ;
    EndEvent = PrevNode(ev);
    EndSeq   = EndEvent->seqnum;

    if (MainWindow) {
        if (refresh) {
            /*
             *        We were already displaying the end of the buffer and we
             *        got new info in, so move the display to the new end of
             *        buffer.
             */
            ShowBuffer(EndSeq, DISPLAY_QUICK);
        } else if (BottomSeq > EndCompleteSeq) {
            /*
             *        We weren't at the very end of the buffer, but there was an
             *        unfinished event displayed somewhere on the screen, so
             *        rescan the currently displayed bufferlines in case it
             *        needs to be updated.
             */
            ShowBuffer(TopSeq, DISPLAY_QUICK);
        } else {
            /*
             *        We're too far up in the buffer to show any of the
             *        new data, but update our internal variables anyway
             *        so we can keep the scroll bar up to date.
             */
            ShowBuffer(TopSeq, DISPLAY_NONE);
        }
    } else {
        /*
         *        Simply update TopSeq accordingly so it will be correct the
         *        next time we open the window
         */
        TopSeq     = EndSeq;
        TopEvent = EndEvent;
    }

    /*
     *        Now mark all new events which are finished as complete, so that
     *        we won't rescan them
     */
    for (ev = newev; NextNode(ev) != NULL && ev->status >= ES_READY;
                     ev = NextNode(ev)) {
        EndCompleteEvent = ev;
        EndCompleteSeq   = ev->seqnum;
    }
    DB("HandleNewEvent-Semaphore-done\n");
    ReleaseSemaphore(&BufSem);

    if (MainWindow) {
        CheckForDirtyMainWindow();
        UNLOCK_LAYERS;
        UpdateMainVScroll();
    }

    if (LogActive && !Disabled) {
        /*
         *        Now output the new events to our logfile. We have to be
         *        very careful doing this since we must not keep the buffer
         *        semaphore locked while doing file output (it could lead
         *        to deadlocks if the file output causes a requester to
         *        appear on the screen, for example). Thus, we must lock
         *        and unlock the semaphore as we scan each event. Sigh.
         */
        LONG latestready;        /* seqnum of highest event that's ES_READY */

        /*
         *        Output the new events to the logfile. We only output
         *        events that are complete, or events that are incomplete
         *        but which have a complete event after them. Any complete
         *        events that have been output earlier are not output
         *        again, unless they were only partially output the first
         *        time.
         */
        ObtainSemaphore(&BufSem);
        ev = HeadNode(&EventList);
        if (ev->seqnum > newseq) {
            newev  = ev;
            newseq = ev->seqnum;
        } else if (newseq == curendcompleteseq) {
            /*
             *        We couldn't advance past the endcompleteseq earlier on
             *        because there was nothing beyond it, so step past now.
             */
            newev = NextNode(newev);
            newseq++;
        }
        for (ev = TailNode(&EventList);
            ev->seqnum > newseq && ev->status < ES_READY; ev = PrevNode(ev))
            ;
        latestready = ev->seqnum;
        if (ev->status < ES_READY)
            latestready--;        /* Just in case ev->seqnum == newseq */

        for (ev = newev; NextNode(ev) != NULL && ev->seqnum <= latestready;
                         ev = NextNode(ev)) {
            int firstchar = 0;

            /*
             *        For each event that is either complete, or partially
             *        complete but followed by a complete event, output it
             *        to the logfile (unless already output).
             */
            if (ev->status >= ES_READY) {
                if ((ev->flags & EFLG_LOGDONE) == 0) {
                    if (ev->flags & EFLG_LOGPARTIAL)
                        firstchar = '\\';
                    else
                        firstchar = ' ';
                    ev->flags |= EFLG_LOGDONE;
                }
            } else if ((ev->flags & EFLG_LOGPARTIAL) == 0) {
                /*
                 *        Output partial event
                 */
                ev->flags |= EFLG_LOGPARTIAL;
                firstchar = '/';
            }

            if (firstchar) {
                /*
                 *        Output the line
                 */
                FormatEvent(LogEFormat, ev, BufferLine+1, 0, LogWidth - 1);
                BufferLine[0]              = firstchar;
                BufferLine[LogWidth+1] = '\n';
                BufferLine[LogWidth+2] = 0;
                ReleaseSemaphore(&BufSem);
                WriteLog(BufferLine);
                ObtainSemaphore(&BufSem);
                /*
                 *        While we had the semaphore released, it's possible
                 *        that the event we're on may have scrolled off the
                 *        buffer. If it has, then give up right now (we'll
                 *        catch the new ones the next time around).
                 */
                if (((Event *)HeadNode(&EventList))->seqnum > latestready)
                    break;
            }
        }
        ReleaseSemaphore(&BufSem);
        if (Paused)
            WriteLog(NULL);    /* Flush log if we're single-stepping */
    }
    if (AutoOpen && !MainWindow && curendseq < EndSeq)
        ShowSnoopDos();
}

/*
 *        CleanupMainWindow()
 *
 *        Frees any resources associated with this module
 */
void CleanupMainWindow(void)
{
    CloseMainWindow();
    if (MainGadList)    FreeGadgets(MainGadList),    MainGadList        = NULL;
    if (BufferFont)        CloseFont(BufferFont),        BufferFont        = NULL;
    if (LogActive)        CloseLog();
}