/* $OpenBSD: wsemul_vt100_subr.c,v 1.32 2024/11/05 15:54:12 miod Exp $ */
/* $NetBSD: wsemul_vt100_subr.c,v 1.7 2000/04/28 21:56:16 mycroft Exp $ */

/*
 * Copyright (c) 1998
 *      Matthias Drochner.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include <sys/param.h>
#include <sys/systm.h>

#include <dev/wscons/wsconsio.h>
#include <dev/wscons/wsksymvar.h>
#include <dev/wscons/wsdisplayvar.h>
#include <dev/wscons/wsemulvar.h>
#include <dev/wscons/wsemul_vt100var.h>

int     vt100_selectattribute(struct wsemul_vt100_emuldata *, int, int, int,
            uint32_t *, uint32_t *);
int     vt100_ansimode(struct wsemul_vt100_emuldata *, int, int);
int     vt100_decmode(struct wsemul_vt100_emuldata *, int, int);
#define VTMODE_SET 33
#define VTMODE_RESET 44
#define VTMODE_REPORT 55

/*
 * scroll up within scrolling region
 */
int
wsemul_vt100_scrollup(struct wsemul_vt100_emuldata *edp, int n)
{
        int help;
        int rc;

        if (n > edp->scrreg_nrows)
                n = edp->scrreg_nrows;

        help = edp->scrreg_nrows - n;
        if (help > 0) {
                WSEMULOP(rc, edp, &edp->abortstate, copyrows,
                    (edp->emulcookie, edp->scrreg_startrow + n,
                     edp->scrreg_startrow, help));
                if (rc != 0)
                        return rc;
        }
        WSEMULOP(rc, edp, &edp->abortstate, eraserows,
            (edp->emulcookie, edp->scrreg_startrow + help, n, edp->bkgdattr));
        if (rc != 0)
                return rc;
#ifdef HAVE_DOUBLE_WIDTH_HEIGHT
        if (edp->dblwid) {
                if (help > 0)
                        memmove(&edp->dblwid[edp->scrreg_startrow],
                            &edp->dblwid[edp->scrreg_startrow + n], help);
                memset(&edp->dblwid[edp->scrreg_startrow + help], 0, n);
        }
        CHECK_DW;
#endif

        return 0;
}

/*
 * scroll down within scrolling region
 */
int
wsemul_vt100_scrolldown(struct wsemul_vt100_emuldata *edp, int n)
{
        int help;
        int rc;

        if (n > edp->scrreg_nrows)
                n = edp->scrreg_nrows;

        help = edp->scrreg_nrows - n;
        if (help > 0) {
                WSEMULOP(rc, edp, &edp->abortstate, copyrows,
                    (edp->emulcookie, edp->scrreg_startrow,
                     edp->scrreg_startrow + n, help));
                if (rc != 0)
                        return rc;
        }
        WSEMULOP(rc, edp, &edp->abortstate, eraserows,
            (edp->emulcookie, edp->scrreg_startrow, n, edp->bkgdattr));
        if (rc != 0)
                return rc;
#ifdef HAVE_DOUBLE_WIDTH_HEIGHT
        if (edp->dblwid) {
                if (help > 0)
                        memmove(&edp->dblwid[edp->scrreg_startrow + n],
                            &edp->dblwid[edp->scrreg_startrow], help);
                memset(&edp->dblwid[edp->scrreg_startrow], 0, n);
        }
        CHECK_DW;
#endif

        return 0;
}

/*
 * erase in display
 */
int
wsemul_vt100_ed(struct wsemul_vt100_emuldata *edp, int arg)
{
        int n;
        int rc;

        switch (arg) {
        case 0: /* cursor to end */
                WSEMULOP(rc, edp, &edp->abortstate, erasecols,
                    ERASECOLS(edp->ccol, COLS_LEFT + 1, edp->bkgdattr));
                if (rc != 0)
                        break;
                n = edp->nrows - edp->crow - 1;
                if (n > 0) {
                        WSEMULOP(rc, edp, &edp->abortstate, eraserows,
                            (edp->emulcookie, edp->crow + 1, n, edp->bkgdattr));
                        if (rc != 0)
                                break;
#ifdef HAVE_DOUBLE_WIDTH_HEIGHT
                        if (edp->dblwid)
                                memset(&edp->dblwid[edp->crow + 1], 0, n);
#endif
                }
                break;
        case 1: /* beginning to cursor */
                if (edp->crow > 0) {
                        WSEMULOP(rc, edp, &edp->abortstate, eraserows,
                            (edp->emulcookie, 0, edp->crow, edp->bkgdattr));
                        if (rc != 0)
                                break;
                }
                WSEMULOP(rc, edp, &edp->abortstate, erasecols,
                    ERASECOLS(0, edp->ccol + 1, edp->bkgdattr));
                if (rc != 0)
                        break;
#ifdef HAVE_DOUBLE_WIDTH_HEIGHT
                if (edp->dblwid) {
                        if (edp->crow > 0)
                                memset(&edp->dblwid[0], 0, edp->crow);
                }
#endif
                break;
        case 2: /* complete display */
                WSEMULOP(rc, edp, &edp->abortstate, eraserows,
                    (edp->emulcookie, 0, edp->nrows, edp->bkgdattr));
                if (rc != 0)
                        break;
#ifdef HAVE_DOUBLE_WIDTH_HEIGHT
                if (edp->dblwid)
                        memset(&edp->dblwid[0], 0, edp->nrows);
#endif
                break;
        default:
#ifdef VT100_PRINTUNKNOWN
                printf("ed(%d) unknown\n", arg);
#endif
                rc = 0;
                break;
        }
        if (rc != 0)
                return rc;

        CHECK_DW;

        return 0;
}

/*
 * erase in line
 */
int
wsemul_vt100_el(struct wsemul_vt100_emuldata *edp, int arg)
{
        int rc;

        switch (arg) {
        case 0: /* cursor to end */
                WSEMULOP(rc, edp, &edp->abortstate, erasecols,
                    ERASECOLS(edp->ccol, COLS_LEFT + 1, edp->bkgdattr));
                break;
        case 1: /* beginning to cursor */
                WSEMULOP(rc, edp, &edp->abortstate, erasecols,
                    ERASECOLS(0, edp->ccol + 1, edp->bkgdattr));
                break;
        case 2: /* complete line */
                WSEMULOP(rc, edp, &edp->abortstate, erasecols,
                    (edp->emulcookie, edp->crow, 0, edp->ncols, edp->bkgdattr));
                break;
        default:
#ifdef VT100_PRINTUNKNOWN
                printf("el(%d) unknown\n", arg);
#endif
                rc = 0;
                break;
        }

        return rc;
}

/*
 * handle commands after CSI (ESC[)
 */
int
wsemul_vt100_handle_csi(struct wsemul_vt100_emuldata *edp,
    struct wsemul_inputstate *instate, int kernel)
{
        int n, m, help, flags, fgcol, bgcol;
        uint32_t attr, bkgdattr;
        u_char c;
        int rc = 0;

        if (instate->inchar >= 0x100)
                c = 0x00;       /* cause the switch below to end in default: */
        else
                c = (u_char)instate->inchar;

#define A3(a, b, c) (((a) << 16) | ((b) << 8) | (c))
        switch (A3(edp->modif1, edp->modif2, c)) {
        case A3('>', '\0', 'c'): /* DA secondary */
                wsdisplay_emulinput(edp->cbcookie, WSEMUL_VT_ID2,
                    sizeof(WSEMUL_VT_ID2) - 1);
                break;

        case A3('\0', '\0', 'J'): /* ED selective erase in display */
        case A3('?', '\0', 'J'): /* DECSED selective erase in display */
                rc = wsemul_vt100_ed(edp, ARG(0));
                break;
        case A3('\0', '\0', 'K'): /* EL selective erase in line */
        case A3('?', '\0', 'K'): /* DECSEL selective erase in line */
                rc = wsemul_vt100_el(edp, ARG(0));
                break;
        case A3('\0', '\0', 'h'): /* SM */
                for (n = 0; n < edp->nargs; n++)
                        vt100_ansimode(edp, ARG(n), VTMODE_SET);
                break;
        case A3('?', '\0', 'h'): /* DECSM */
                for (n = 0; n < edp->nargs; n++) {
                        rc = vt100_decmode(edp, ARG(n), VTMODE_SET);
                        if (rc != 0)
                                break;
                }
                break;
        case A3('\0', '\0', 'l'): /* RM */
                for (n = 0; n < edp->nargs; n++)
                        vt100_ansimode(edp, ARG(n), VTMODE_RESET);
                break;
        case A3('?', '\0', 'l'): /* DECRM */
                for (n = 0; n < edp->nargs; n++) {
                        rc = vt100_decmode(edp, ARG(n), VTMODE_RESET);
                        if (rc != 0)
                                break;
                }
                break;
        case A3('\0', '$', 'p'): /* DECRQM request mode ANSI */
                vt100_ansimode(edp, ARG(0), VTMODE_REPORT);
                break;
        case A3('?', '$', 'p'): /* DECRQM request mode DEC */
                rc = vt100_decmode(edp, ARG(0), VTMODE_REPORT);
                break;
        case A3('\0', '\0', 'i'): /* MC printer controller mode */
        case A3('?', '\0', 'i'): /* MC printer controller mode */
                switch (ARG(0)) {
                case 0: /* print screen */
                case 1: /* print cursor line */
                case 4: /* off */
                case 5: /* on */
#ifdef VT100_PRINTNOTIMPL
                        printf("CSI%di ignored\n", ARG(0));
#endif
                        break;
                default:
#ifdef VT100_PRINTUNKNOWN
                        printf("CSI%di unknown\n", ARG(0));
#endif
                        break;
                }
                break;

#define A2(a, b) (((a) << 8) | (b))
        case A2('!', 'p'): /* DECSTR soft reset VT300 only */
                wsemul_vt100_reset(edp);
                break;

        case A2('"', 'p'): /* DECSCL */
                switch (ARG(0)) {
                case 61: /* VT100 mode (no further arguments!) */
                        break;
                case 62:
                case 63: /* VT300 mode */
                        break;
                default:
#ifdef VT100_PRINTUNKNOWN
                        printf("CSI%d\"p unknown\n", ARG(0));
#endif
                        break;
                }
                switch (ARG(1)) {
                case 0:
                case 2: /* 8-bit controls */
#ifdef VT100_PRINTNOTIMPL
                        printf("CSI%d;%d\"p ignored\n", ARG(0), ARG(1));
#endif
                        break;
                case 1: /* 7-bit controls */
                        break;
                default:
#ifdef VT100_PRINTUNKNOWN
                        printf("CSI%d;%d\"p unknown\n", ARG(0), ARG(1));
#endif
                        break;
                }
                break;
        case A2('"', 'q'): /* DECSCA select character attribute VT300 */
                switch (ARG(0)) {
                case 0:
                case 1: /* erasable */
                        break;
                case 2: /* not erasable */
#ifdef VT100_PRINTNOTIMPL
                        printf("CSI2\"q ignored\n");
#endif
                        break;
                default:
#ifdef VT100_PRINTUNKNOWN
                        printf("CSI%d\"q unknown\n", ARG(0));
#endif
                        break;
                }
                break;

        case A2('$', 'u'): /* DECRQTSR request terminal status report */
                switch (ARG(0)) {
                case 0: /* ignored */
                        break;
                case 1: /* terminal state report */
#ifdef VT100_PRINTNOTIMPL
                        printf("CSI1$u ignored\n");
#endif
                        break;
                default:
#ifdef VT100_PRINTUNKNOWN
                        printf("CSI%d$u unknown\n", ARG(0));
#endif
                        break;
                }
                break;
        case A2('$', 'w'): /* DECRQPSR request presentation status report
                                (VT300 only) */
                switch (ARG(0)) {
                case 0: /* error */
                        break;
                case 1: /* cursor information report */
#ifdef VT100_PRINTNOTIMPL
                        printf("CSI1$w ignored\n");
#endif
                        break;
                case 2: /* tab stop report */
                    {
                        int i, n, ps = 0;
                        char buf[20];

                        wsdisplay_emulinput(edp->cbcookie, "\033P2$u", 5);
                        if (edp->tabs != NULL)
                            for (i = 0; i < edp->ncols; i++)
                                if (edp->tabs[i]) {
                                        n = snprintf(buf, sizeof buf, "%s%d",
                                            (ps ? "/" : ""), i + 1);
                                        if (n == -1)
                                                n = 0;
                                        else if (n >= sizeof buf)
                                                n = sizeof buf - 1;
                                        wsdisplay_emulinput(edp->cbcookie,
                                            buf, n);
                                        ps = 1;
                                }
                        wsdisplay_emulinput(edp->cbcookie, "\033\\", 2);
                    }
                        break;
                default:
#ifdef VT100_PRINTUNKNOWN
                        printf("CSI%d$w unknown\n", ARG(0));
#endif
                        break;
                }
                break;
        /* gratuitous { for brace matching with the next line */
        case A2('$', '}'): /* DECSASD select active status display */
                switch (ARG(0)) {
                case 0: /* main display */
                case 1: /* status line */
#ifdef VT100_PRINTNOTIMPL       /* { */
                        printf("CSI%d$} ignored\n", ARG(0));
#endif
                        break;
                default:
#ifdef VT100_PRINTUNKNOWN       /* { */
                        printf("CSI%d$} unknown\n", ARG(0));
#endif
                        break;
                }
                break;
        case A2('$', '~'): /* DECSSDD select status line type */
                switch (ARG(0)) {
                case 0: /* none */
                case 1: /* indicator */
                case 2: /* host-writable */
#ifdef VT100_PRINTNOTIMPL
                        printf("CSI%d$~ ignored\n", ARG(0));
#endif
                        break;
                default:
#ifdef VT100_PRINTUNKNOWN
                        printf("CSI%d$~ unknown\n", ARG(0));
#endif
                        break;
                }
                break;

        case A2('&', 'u'): /* DECRQUPSS request user preferred
                                  supplemental set */
                wsdisplay_emulinput(edp->cbcookie, "\033P0!u%5\033\\", 9);
                break;

        case '@': /* ICH insert character VT300 only */
                n = min(DEF1_ARG(0), COLS_LEFT + 1);
                help = NCOLS - (edp->ccol + n);
                if (help > 0) {
                        WSEMULOP(rc, edp, &edp->abortstate, copycols,
                            COPYCOLS(edp->ccol, edp->ccol + n, help));
                        if (rc != 0)
                                break;
                }
                WSEMULOP(rc, edp, &edp->abortstate, erasecols,
                    ERASECOLS(edp->ccol, n, edp->bkgdattr));
                break;
        case 'A': /* CUU */
                n = ROWS_ABOVE;
                if (n > 0)
                        edp->crow -= min(DEF1_ARG(0), n);
                CHECK_DW;
                break;
        case 'B': /* CUD */
                n = ROWS_BELOW;
                if (n > 0)
                        edp->crow += min(DEF1_ARG(0), n);
                CHECK_DW;
                break;
        case 'C': /* CUF */
                edp->ccol += min(DEF1_ARG(0), COLS_LEFT);
                break;
        case 'D': /* CUB */
                edp->ccol -= min(DEF1_ARG(0), edp->ccol);
                edp->flags &= ~VTFL_LASTCHAR;
                break;
        case 'G': /* CHA */
        case '`': /* HPA */
                edp->ccol = min(DEF1_ARG(0), edp->ncols) - 1;
                break;
        case 'H': /* CUP */
        case 'f': /* HVP */
                if (edp->flags & VTFL_DECOM)
                        edp->crow = edp->scrreg_startrow +
                            min(DEF1_ARG(0), edp->scrreg_nrows) - 1;
                else
                        edp->crow = min(DEF1_ARG(0), edp->nrows) - 1;
                CHECK_DW;
                edp->ccol = min(DEF1_ARG(1), NCOLS) - 1;
                edp->flags &= ~VTFL_LASTCHAR;
                break;
        case 'L': /* IL insert line */
        case 'M': /* DL delete line */
                if (edp->crow >= edp->scrreg_startrow &&
                    edp->crow < edp->scrreg_startrow + edp->scrreg_nrows) {
                        int savscrstartrow, savscrnrows;

                        n = min(DEF1_ARG(0), ROWS_BELOW + 1);
                        savscrstartrow = edp->scrreg_startrow;
                        savscrnrows = edp->scrreg_nrows;
                        edp->scrreg_nrows -= ROWS_ABOVE;
                        edp->scrreg_startrow = edp->crow;
                        if (c == 'L')
                                rc = wsemul_vt100_scrolldown(edp, n);
                        else
                                rc = wsemul_vt100_scrollup(edp, n);
                        edp->scrreg_startrow = savscrstartrow;
                        edp->scrreg_nrows = savscrnrows;
                } /* else not within scrolling region, ignore the sequence */
                break;
        case 'P': /* DCH delete character */
                n = min(DEF1_ARG(0), COLS_LEFT + 1);
                help = NCOLS - (edp->ccol + n);
                if (help > 0) {
                        WSEMULOP(rc, edp, &edp->abortstate, copycols,
                            COPYCOLS(edp->ccol + n, edp->ccol, help));
                        if (rc != 0)
                                break;
                }
                WSEMULOP(rc, edp, &edp->abortstate, erasecols,
                    ERASECOLS(NCOLS - n, n, edp->bkgdattr));
                break;
        case 'S': /* SU scroll up */
                wsemul_vt100_scrollup(edp, DEF1_ARG(0));
                break;
        case 'T': /* SD scroll down */
                wsemul_vt100_scrolldown(edp, DEF1_ARG(0));
                break;
        case 'X': /* ECH erase character */
                n = min(DEF1_ARG(0), COLS_LEFT + 1);
                WSEMULOP(rc, edp, &edp->abortstate, erasecols,
                    ERASECOLS(edp->ccol, n, edp->bkgdattr));
                break;
        case 'Z': /* CBT */
                if (edp->ccol == 0)
                        break;
                for (m = 0; m < DEF1_ARG(0); m++) {
                        if (edp->tabs) {
                                for (n = edp->ccol - 1; n > 0; n--) {
                                        if (edp->tabs[n])
                                                break;
                                }
                        } else
                                n = (edp->ccol - 1) & ~7;
                        edp->ccol = n;
                        if (n == 0)
                                break;
                }
                break;
        case 'b': /* REP */
                /*
                 * We arbitrarily limit the repeat count to 65535 to avoid
                 * uninterruptible flooding of the console. This matches
                 * current xterm behaviour.
                 */
                n = min(DEF1_ARG(0), 65535);
                instate->inchar = instate->last_output;
                rc = wsemul_vt100_output_normal(edp, instate, kernel, n);
                break;
        case 'c': /* DA primary */
                if (ARG(0) == 0)
                        wsdisplay_emulinput(edp->cbcookie, WSEMUL_VT_ID1,
                            sizeof(WSEMUL_VT_ID1) - 1);
                break;
        case 'd': /* VPA */
                edp->crow = min(DEF1_ARG(0), edp->nrows) - 1;
                break;
        case 'g': /* TBC */
                if (edp->tabs != NULL)
                        switch (ARG(0)) {
                        case 0:
                                edp->tabs[edp->ccol] = 0;
                                break;
                        case 3:
                                memset(edp->tabs, 0, edp->ncols);
                                break;
                        default:
#ifdef VT100_PRINTUNKNOWN
                                printf("CSI%dg unknown\n", ARG(0));
#endif
                                break;
                        }
                break;
        case 'm': /* SGR select graphic rendition */
                flags = edp->attrflags;
                fgcol = edp->fgcol;
                bgcol = edp->bgcol;
                for (n = 0; n < edp->nargs; n++) {
                        switch (ARG(n)) {
                        case 0: /* reset */
                                if (n == edp->nargs - 1) {
                                        edp->bkgdattr = edp->curattr = edp->defattr;
                                        edp->attrflags = 0;
                                        edp->fgcol = WSCOL_WHITE;
                                        edp->bgcol = WSCOL_BLACK;
                                        return 0;
                                }
                                flags = 0;
                                fgcol = WSCOL_WHITE;
                                bgcol = WSCOL_BLACK;
                                break;
                        case 1: /* bold */
                                flags |= WSATTR_HILIT;
                                break;
                        case 4: /* underline */
                                flags |= WSATTR_UNDERLINE;
                                break;
                        case 5: /* blink */
                                flags |= WSATTR_BLINK;
                                break;
                        case 7: /* reverse */
                                flags |= WSATTR_REVERSE;
                                break;
                        case 22: /* ~bold VT300 only */
                                flags &= ~WSATTR_HILIT;
                                break;
                        case 24: /* ~underline VT300 only */
                                flags &= ~WSATTR_UNDERLINE;
                                break;
                        case 25: /* ~blink VT300 only */
                                flags &= ~WSATTR_BLINK;
                                break;
                        case 27: /* ~reverse VT300 only */
                                flags &= ~WSATTR_REVERSE;
                                break;
                        case 30: case 31: case 32: case 33:
                        case 34: case 35: case 36: case 37:
                                /* fg color */
                                flags |= WSATTR_WSCOLORS;
                                fgcol = ARG(n) - 30;
                                break;
                        case 39:
                                /* reset fg color */
                                fgcol = WSCOL_WHITE;
                                if (bgcol == WSCOL_BLACK)
                                        flags &= ~WSATTR_WSCOLORS;
                                break;
                        case 40: case 41: case 42: case 43:
                        case 44: case 45: case 46: case 47:
                                /* bg color */
                                flags |= WSATTR_WSCOLORS;
                                bgcol = ARG(n) - 40;
                                break;
                        case 49:
                                /* reset bg color */
                                bgcol = WSCOL_BLACK;
                                if (fgcol == WSCOL_WHITE)
                                        flags &= ~WSATTR_WSCOLORS;
                                break;
                        case 90: case 91: case 92: case 93:
                        case 94: case 95: case 96: case 97:
                                /* bright foreground color */
                                flags |= WSATTR_WSCOLORS;
                                fgcol = ARG(n) - 82;
                                break;
                        case 100: case 101: case 102: case 103:
                        case 104: case 105: case 106: case 107:
                                /* bright background color */
                                flags |= WSATTR_WSCOLORS;
                                bgcol = ARG(n) - 92;
                                break;
                        default:
#ifdef VT100_PRINTUNKNOWN
                                printf("CSI%dm unknown\n", ARG(n));
#endif
                                break;
                        }
                }
                if (vt100_selectattribute(edp, flags, fgcol, bgcol, &attr,
                    &bkgdattr)) {
#ifdef VT100_DEBUG
                        printf("error allocating attr %d/%d/%x\n",
                               fgcol, bgcol, flags);
#endif
                } else {
                        edp->curattr = attr;
                        edp->bkgdattr = bkgdattr;
                        edp->attrflags = flags;
                        edp->fgcol = fgcol;
                        edp->bgcol = bgcol;
                }
                break;
        case 'n': /* reports */
                switch (ARG(0)) {
                case 5: /* DSR operating status */
                        /* 0 = OK, 3 = malfunction */
                        wsdisplay_emulinput(edp->cbcookie, "\033[0n", 4);
                        break;
                case 6: /* DSR cursor position report */
                    {
                        char buf[20];
                        int row;
                        if (edp->flags & VTFL_DECOM) {
                                row = ROWS_ABOVE;
                                if (row < 0)
                                        row = 0;
                        } else
                                row = edp->crow;
                        n = snprintf(buf, sizeof buf, "\033[%d;%dR",
                                    row + 1, edp->ccol + 1);
                        if (n == -1)
                                n = 0;
                        else if (n >= sizeof buf)
                                n = sizeof buf - 1;
                        wsdisplay_emulinput(edp->cbcookie, buf, n);
                    }
                        break;
                case 15: /* DSR printer status */
                        /* 13 = no printer, 10 = ready, 11 = not ready */
                        wsdisplay_emulinput(edp->cbcookie, "\033[?13n", 6);
                        break;
                case 25: /* UDK status - VT300 only */
                        /* 20 = locked, 21 = unlocked */
                        wsdisplay_emulinput(edp->cbcookie, "\033[?21n", 6);
                        break;
                case 26: /* keyboard dialect */
                        /* 1 = north american , 7 = german */
                        wsdisplay_emulinput(edp->cbcookie, "\033[?27;1n", 8);
                        break;
                default:
#ifdef VT100_PRINTUNKNOWN
                        printf("CSI%dn unknown\n", ARG(0));
#endif
                        break;
                }
                break;
        case 'r': /* DECSTBM set top/bottom margins */
                help = min(DEF1_ARG(0), edp->nrows) - 1;
                n = min(DEFx_ARG(1, edp->nrows), edp->nrows) - help;
                if (n < 2) {
                        /* minimal scrolling region has 2 lines */
                        return 0;
                } else {
                        edp->scrreg_startrow = help;
                        edp->scrreg_nrows = n;
                }
                edp->crow = ((edp->flags & VTFL_DECOM) ?
                             edp->scrreg_startrow : 0);
                edp->ccol = 0;
                break;
        case 's':
                edp->flags |= VTFL_SAVEDCURS;
                edp->savedcursor_row = edp->crow;
                edp->savedcursor_col = edp->ccol;
                break;
        case 'u':
                if (edp->flags & VTFL_SAVEDCURS) {
                        edp->crow = edp->savedcursor_row;
                        edp->ccol = edp->savedcursor_col;
                }
                break;
        case 'y':
                switch (ARG(0)) {
                case 4: /* DECTST invoke confidence test */
                        /* ignore */
                        break;
                default:
#ifdef VT100_PRINTUNKNOWN
                        printf("CSI%dy unknown\n", ARG(0));
#endif
                        break;
                }
                break;
        default:
#ifdef VT100_PRINTUNKNOWN
                printf("CSI %x (%d, %d) unknown\n",
                    instate->inchar, ARG(0), ARG(1));
#endif
                break;
        }

        return rc;
}

/*
 * get an attribute from the graphics driver,
 * try to find replacements if the desired appearance
 * is not supported
 */
int
vt100_selectattribute(struct wsemul_vt100_emuldata *edp, int flags, int fgcol,
    int bgcol, uint32_t *attr, uint32_t *bkgdattr)
{
        int error;

        if ((flags & WSATTR_WSCOLORS) &&
            !(edp->scrcapabilities & WSSCREEN_WSCOLORS)) {
                flags &= ~WSATTR_WSCOLORS;
#ifdef VT100_DEBUG
                printf("colors ignored (impossible)\n");
#endif
        }
        error = (*edp->emulops->pack_attr)(edp->emulcookie, fgcol, bgcol,
            flags & WSATTR_WSCOLORS, bkgdattr);
        if (error)
                return (error);

        if ((flags & WSATTR_HILIT) &&
            !(edp->scrcapabilities & WSSCREEN_HILIT)) {
                flags &= ~WSATTR_HILIT;
                if (edp->scrcapabilities & WSSCREEN_WSCOLORS) {
                        fgcol = WSCOL_RED;
                        flags |= WSATTR_WSCOLORS;
                } else {
#ifdef VT100_DEBUG
                        printf("bold ignored (impossible)\n");
#endif
                }
        }
        if ((flags & WSATTR_UNDERLINE) &&
            !(edp->scrcapabilities & WSSCREEN_UNDERLINE)) {
                flags &= ~WSATTR_UNDERLINE;
                if (edp->scrcapabilities & WSSCREEN_WSCOLORS) {
                        fgcol = WSCOL_CYAN;
                        flags &= ~WSATTR_UNDERLINE;
                        flags |= WSATTR_WSCOLORS;
                } else {
#ifdef VT100_DEBUG
                        printf("underline ignored (impossible)\n");
#endif
                }
        }
        if ((flags & WSATTR_BLINK) &&
            !(edp->scrcapabilities & WSSCREEN_BLINK)) {
                flags &= ~WSATTR_BLINK;
#ifdef VT100_DEBUG
                printf("blink ignored (impossible)\n");
#endif
        }
        if ((flags & WSATTR_REVERSE) &&
            !(edp->scrcapabilities & WSSCREEN_REVERSE)) {
                flags &= ~WSATTR_REVERSE;
                if (edp->scrcapabilities & WSSCREEN_WSCOLORS) {
                        int help;
                        help = bgcol;
                        bgcol = fgcol;
                        fgcol = help;
                        flags |= WSATTR_WSCOLORS;
                } else {
#ifdef VT100_DEBUG
                        printf("reverse ignored (impossible)\n");
#endif
                }
        }
        error = (*edp->emulops->pack_attr)(edp->emulcookie, fgcol, bgcol,
                                            flags, attr);
        if (error)
                return (error);

        return (0);
}

/*
 * handle device control sequences if the main state machine
 * told so by setting edp->dcstype to a nonzero value
 */
void
wsemul_vt100_handle_dcs(struct wsemul_vt100_emuldata *edp)
{
        int i, pos;

        switch (edp->dcstype) {
        case 0: /* not handled */
                return;
        case DCSTYPE_TABRESTORE:
                if (edp->tabs != NULL) {
                        memset(edp->tabs, 0, edp->ncols);
                        pos = 0;
                        if (edp->dcsarg == NULL)
                                goto out;
                        for (i = 0; i < edp->dcspos; i++) {
                                char c = edp->dcsarg[i];
                                switch (c) {
                                case '0': case '1': case '2': case '3':
                                case '4': case '5': case '6': case '7':
                                case '8': case '9':
                                        pos = pos * 10 + (c - '0');
                                        if (pos > edp->ncols)
                                                goto out;
                                        break;
                                case '/':
                                        if (pos > 0)
                                                edp->tabs[pos - 1] = 1;
                                        pos = 0;
                                        break;
                                default:
#ifdef VT100_PRINTUNKNOWN
                                        printf("unknown char %c in DCS\n", c);
#endif
                                        break;
                                }
                        }
                        if (pos > 0)
                                edp->tabs[pos - 1] = 1;
                }
                break;
        default:
#ifdef VT100_PRINTUNKNOWN
                printf("wsemul_vt100_handle_dcs: bad type %d\n", edp->dcstype);
#endif
                break;
        }
out:
        edp->dcstype = 0;
}

int
vt100_ansimode(struct wsemul_vt100_emuldata *edp, int nr, int op)
{
        int res = 0; /* default: unknown */

        switch (nr) {
        case 2: /* KAM keyboard locked/unlocked */
                break;
        case 3: /* CRM control representation */
                break;
        case 4: /* IRM insert/replace characters */
                if (op == VTMODE_SET)
                        edp->flags |= VTFL_INSERTMODE;
                else if (op == VTMODE_RESET)
                        edp->flags &= ~VTFL_INSERTMODE;
                res = ((edp->flags & VTFL_INSERTMODE) ? 1 : 2);
                break;
        case 10: /* HEM horizontal editing (permanently reset) */
                res = 4;
                break;
        case 12: /* SRM local echo off/on */
                res = 4; /* permanently reset ??? */
                break;
        case 20: /* LNM newline = newline/linefeed */
                break;
        default:
#ifdef VT100_PRINTUNKNOWN
                printf("ANSI mode %d unknown\n", nr);
#endif
                break;
        }
        return (res);
}

int
vt100_decmode(struct wsemul_vt100_emuldata *edp, int nr, int op)
{
#if 0   /* res unused... return it by reference if ever necessary */
        int res = 0; /* default: unknown */
#endif
        int flags = edp->flags;
        int rc = 0;

        switch (nr) {
        case 1: /* DECCKM application/nomal cursor keys */
                if (op == VTMODE_SET)
                        flags |= VTFL_APPLCURSOR;
                else if (op == VTMODE_RESET)
                        flags &= ~VTFL_APPLCURSOR;
#if 0
                res = ((flags & VTFL_APPLCURSOR) ? 1 : 2);
#endif
                break;
        case 2: /* DECANM ANSI vt100/vt52 */
#if 0
                res = 3; /* permanently set ??? */
#endif
                break;
        case 3: /* DECCOLM 132/80 cols */
        case 4: /* DECSCLM smooth/jump scroll */
        case 5: /* DECSCNM light/dark background */
#if 0
                res = 4; /* all permanently reset ??? */
#endif
                break;
        case 6: /* DECOM move within/outside margins */
                if (op == VTMODE_SET)
                        flags |= VTFL_DECOM;
                else if (op == VTMODE_RESET)
                        flags &= ~VTFL_DECOM;
#if 0
                res = ((flags & VTFL_DECOM) ? 1 : 2);
#endif
                break;
        case 7: /* DECAWM autowrap */
                if (op == VTMODE_SET)
                        flags |= VTFL_DECAWM;
                else if (op == VTMODE_RESET)
                        flags &= ~VTFL_DECAWM;
#if 0
                res = ((flags & VTFL_DECAWM) ? 1 : 2);
#endif
                break;
        case 8: /* DECARM keyboard autorepeat */
                break;
        case 18: /* DECPFF print form feed */
                break;
        case 19: /* DECPEX printer extent: screen/scrolling region */
                break;
        case 25: /* DECTCEM text cursor on/off */
                if (op == VTMODE_SET)
                        flags |= VTFL_CURSORON;
                else if (op == VTMODE_RESET)
                        flags &= ~VTFL_CURSORON;
                if (flags != edp->flags)
                        WSEMULOP(rc, edp, &edp->abortstate, cursor,
                            (edp->emulcookie, flags & VTFL_CURSORON, edp->crow,
                             edp->ccol));
#if 0
                res = ((flags & VTFL_CURSORON) ? 1 : 2);
#endif
                break;
        case 42: /* DECNRCM use 7-bit NRC /
                    7/8 bit from DEC multilingual or ISO-latin-1*/
                if (op == VTMODE_SET)
                        flags |= VTFL_NATCHARSET;
                else if (op == VTMODE_RESET)
                        flags &= ~VTFL_NATCHARSET;
#if 0
                res = ((flags & VTFL_NATCHARSET) ? 1 : 2);
#endif
                break;
        case 66: /* DECNKM numeric keypad */
                break;
        case 68: /* DECKBUM keyboard usage data processing/typewriter */
                break;
        default:
#ifdef VT100_PRINTUNKNOWN
                printf("DEC mode %d unknown\n", nr);
#endif
                break;
        }
        edp->flags = flags;

        return rc;
}