+eschandle(uchar ascii)
+{
+ switch (ascii) {
+ case '[':
+ term.esc |= ESC_CSI;
+ return 0;
+ case '#':
+ term.esc |= ESC_TEST;
+ return 0;
+ case '%':
+ term.esc |= ESC_UTF8;
+ return 0;
+ case 'P': /* DCS -- Device Control String */
+ case '_': /* APC -- Application Program Command */
+ case '^': /* PM -- Privacy Message */
+ case ']': /* OSC -- Operating System Command */
+ case 'k': /* old title set compatibility */
+ tstrsequence(ascii);
+ return 0;
+ case 'n': /* LS2 -- Locking shift 2 */
+ case 'o': /* LS3 -- Locking shift 3 */
+ term.charset = 2 + (ascii - 'n');
+ break;
+ case '(': /* GZD4 -- set primary charset G0 */
+ case ')': /* G1D4 -- set secondary charset G1 */
+ case '*': /* G2D4 -- set tertiary charset G2 */
+ case '+': /* G3D4 -- set quaternary charset G3 */
+ term.icharset = ascii - '(';
+ term.esc |= ESC_ALTCHARSET;
+ return 0;
+ case 'D': /* IND -- Linefeed */
+ if (term.c.y == term.bot) {
+ tscrollup(term.top, 1);
+ } else {
+ tmoveto(term.c.x, term.c.y+1);
+ }
+ break;
+ case 'E': /* NEL -- Next line */
+ tnewline(1); /* always go to first col */
+ break;
+ case 'H': /* HTS -- Horizontal tab stop */
+ term.tabs[term.c.x] = 1;
+ break;
+ case 'M': /* RI -- Reverse index */
+ if (term.c.y == term.top) {
+ tscrolldown(term.top, 1);
+ } else {
+ tmoveto(term.c.x, term.c.y-1);
+ }
+ break;
+ case 'Z': /* DECID -- Identify Terminal */
+ ttywrite(vtiden, strlen(vtiden), 0);
+ break;
+ case 'c': /* RIS -- Reset to initial state */
+ treset();
+ resettitle();
+ xloadcols();
+ break;
+ case '=': /* DECPAM -- Application keypad */
+ xsetmode(1, MODE_APPKEYPAD);
+ break;
+ case '>': /* DECPNM -- Normal keypad */
+ xsetmode(0, MODE_APPKEYPAD);
+ break;
+ case '7': /* DECSC -- Save Cursor */
+ tcursor(CURSOR_SAVE);
+ break;
+ case '8': /* DECRC -- Restore Cursor */
+ tcursor(CURSOR_LOAD);
+ break;
+ case '\\': /* ST -- String Terminator */
+ if (term.esc & ESC_STR_END)
+ strhandle();
+ break;
+ default:
+ fprintf(stderr, "erresc: unknown sequence ESC 0x%02X '%c'\n",
+ (uchar) ascii, isprint(ascii)? ascii:'.');
+ break;
+ }
+ return 1;
+}
+
+void
+tputc(Rune u)
+{
+ char c[UTF_SIZ];
+ int control;
+ int width, len;
+ Glyph *gp;
+
+ control = ISCONTROL(u);
+ if (u < 127 || !IS_SET(MODE_UTF8)) {
+ c[0] = u;
+ width = len = 1;
+ } else {
+ len = utf8encode(u, c);
+ if (!control && (width = wcwidth(u)) == -1)
+ width = 1;
+ }
+
+ if (IS_SET(MODE_PRINT))
+ tprinter(c, len);
+
+ /*
+ * STR sequence must be checked before anything else
+ * because it uses all following characters until it
+ * receives a ESC, a SUB, a ST or any other C1 control
+ * character.
+ */
+ if (term.esc & ESC_STR) {
+ if (u == '\a' || u == 030 || u == 032 || u == 033 ||
+ ISCONTROLC1(u)) {
+ term.esc &= ~(ESC_START|ESC_STR);
+ term.esc |= ESC_STR_END;
+ goto check_control_code;
+ }
+
+ if (strescseq.len+len >= strescseq.siz) {
+ /*
+ * Here is a bug in terminals. If the user never sends
+ * some code to stop the str or esc command, then st
+ * will stop responding. But this is better than
+ * silently failing with unknown characters. At least
+ * then users will report back.
+ *
+ * In the case users ever get fixed, here is the code:
+ */
+ /*
+ * term.esc = 0;
+ * strhandle();
+ */
+ if (strescseq.siz > (SIZE_MAX - UTF_SIZ) / 2)
+ return;
+ strescseq.siz *= 2;
+ strescseq.buf = xrealloc(strescseq.buf, strescseq.siz);
+ }
+
+ memmove(&strescseq.buf[strescseq.len], c, len);
+ strescseq.len += len;
+ return;
+ }
+
+check_control_code:
+ /*
+ * Actions of control codes must be performed as soon they arrive
+ * because they can be embedded inside a control sequence, and
+ * they must not cause conflicts with sequences.
+ */
+ if (control) {
+ tcontrolcode(u);
+ /*
+ * control codes are not shown ever
+ */
+ if (!term.esc)
+ term.lastc = 0;
+ return;
+ } else if (term.esc & ESC_START) {
+ if (term.esc & ESC_CSI) {
+ csiescseq.buf[csiescseq.len++] = u;
+ if (BETWEEN(u, 0x40, 0x7E)
+ || csiescseq.len >= \
+ sizeof(csiescseq.buf)-1) {
+ term.esc = 0;
+ csiparse();
+ csihandle();
+ }
+ return;
+ } else if (term.esc & ESC_UTF8) {
+ tdefutf8(u);
+ } else if (term.esc & ESC_ALTCHARSET) {
+ tdeftran(u);
+ } else if (term.esc & ESC_TEST) {
+ tdectest(u);
+ } else {
+ if (!eschandle(u))
+ return;
+ /* sequence already finished */
+ }
+ term.esc = 0;
+ /*
+ * All characters which form part of a sequence are not
+ * printed
+ */
+ return;
+ }
+ if (selected(term.c.x, term.c.y))
+ selclear();
+
+ gp = &term.line[term.c.y][term.c.x];
+ if (IS_SET(MODE_WRAP) && (term.c.state & CURSOR_WRAPNEXT)) {
+ gp->mode |= ATTR_WRAP;
+ tnewline(1);
+ gp = &term.line[term.c.y][term.c.x];
+ }
+
+ if (IS_SET(MODE_INSERT) && term.c.x+width < term.col)
+ memmove(gp+width, gp, (term.col - term.c.x - width) * sizeof(Glyph));
+
+ if (term.c.x+width > term.col) {
+ tnewline(1);
+ gp = &term.line[term.c.y][term.c.x];
+ }
+
+ tsetchar(u, &term.c.attr, term.c.x, term.c.y);
+ term.lastc = u;
+
+ if (width == 2) {
+ gp->mode |= ATTR_WIDE;
+ if (term.c.x+1 < term.col) {
+ gp[1].u = '\0';
+ gp[1].mode = ATTR_WDUMMY;
+ }
+ }
+ if (term.c.x+width < term.col) {
+ tmoveto(term.c.x+width, term.c.y);
+ } else {
+ term.c.state |= CURSOR_WRAPNEXT;
+ }
+}
+
+int
+twrite(const char *buf, int buflen, int show_ctrl)
+{
+ int charsize;
+ Rune u;
+ int n;
+
+ for (n = 0; n < buflen; n += charsize) {
+ if (IS_SET(MODE_UTF8)) {
+ /* process a complete utf8 char */
+ charsize = utf8decode(buf + n, &u, buflen - n);
+ if (charsize == 0)
+ break;
+ } else {
+ u = buf[n] & 0xFF;
+ charsize = 1;
+ }
+ if (show_ctrl && ISCONTROL(u)) {
+ if (u & 0x80) {
+ u &= 0x7f;
+ tputc('^');
+ tputc('[');
+ } else if (u != '\n' && u != '\r' && u != '\t') {
+ u ^= 0x40;
+ tputc('^');
+ }
+ }
+ tputc(u);
+ }
+ return n;
+}
+
+void
+tresize(int col, int row)
+{
+ int i;
+ int minrow = MIN(row, term.row);
+ int mincol = MIN(col, term.col);
+ int *bp;
+ TCursor c;
+
+ if (col < 1 || row < 1) {
+ fprintf(stderr,
+ "tresize: error resizing to %dx%d\n", col, row);
+ return;
+ }
+
+ /*
+ * slide screen to keep cursor where we expect it -
+ * tscrollup would work here, but we can optimize to
+ * memmove because we're freeing the earlier lines
+ */
+ for (i = 0; i <= term.c.y - row; i++) {
+ free(term.line[i]);
+ free(term.alt[i]);
+ }
+ /* ensure that both src and dst are not NULL */
+ if (i > 0) {
+ memmove(term.line, term.line + i, row * sizeof(Line));
+ memmove(term.alt, term.alt + i, row * sizeof(Line));
+ }
+ for (i += row; i < term.row; i++) {
+ free(term.line[i]);
+ free(term.alt[i]);
+ }
+
+ /* resize to new height */
+ term.line = xrealloc(term.line, row * sizeof(Line));
+ term.alt = xrealloc(term.alt, row * sizeof(Line));
+ term.dirty = xrealloc(term.dirty, row * sizeof(*term.dirty));
+ term.tabs = xrealloc(term.tabs, col * sizeof(*term.tabs));
+
+ /* resize each row to new width, zero-pad if needed */
+ for (i = 0; i < minrow; i++) {
+ term.line[i] = xrealloc(term.line[i], col * sizeof(Glyph));
+ term.alt[i] = xrealloc(term.alt[i], col * sizeof(Glyph));
+ }
+
+ /* allocate any new rows */
+ for (/* i = minrow */; i < row; i++) {
+ term.line[i] = xmalloc(col * sizeof(Glyph));
+ term.alt[i] = xmalloc(col * sizeof(Glyph));
+ }
+ if (col > term.col) {
+ bp = term.tabs + term.col;
+
+ memset(bp, 0, sizeof(*term.tabs) * (col - term.col));
+ while (--bp > term.tabs && !*bp)
+ /* nothing */ ;
+ for (bp += tabspaces; bp < term.tabs + col; bp += tabspaces)
+ *bp = 1;
+ }
+ /* update terminal size */
+ term.col = col;
+ term.row = row;
+ /* reset scrolling region */
+ tsetscroll(0, row-1);
+ /* make use of the LIMIT in tmoveto */
+ tmoveto(term.c.x, term.c.y);
+ /* Clearing both screens (it makes dirty all lines) */
+ c = term.c;
+ for (i = 0; i < 2; i++) {
+ if (mincol < col && 0 < minrow) {
+ tclearregion(mincol, 0, col - 1, minrow - 1);
+ }
+ if (0 < col && minrow < row) {
+ tclearregion(0, minrow, col - 1, row - 1);
+ }
+ tswapscreen();
+ tcursor(CURSOR_LOAD);
+ }
+ term.c = c;
+}
+
+void
+resettitle(void)
+{
+ xsettitle(NULL);
+}
+
+void
+drawregion(int x1, int y1, int x2, int y2)
+{
+ int y;
+
+ for (y = y1; y < y2; y++) {
+ if (!term.dirty[y])
+ continue;
+
+ term.dirty[y] = 0;
+ xdrawline(term.line[y], x1, y, x2);
+ }
+}
+
+void
+draw(void)
+{
+ int cx = term.c.x, ocx = term.ocx, ocy = term.ocy;
+
+ if (!xstartdraw())
+ return;
+
+ /* adjust cursor position */
+ LIMIT(term.ocx, 0, term.col-1);
+ LIMIT(term.ocy, 0, term.row-1);
+ if (term.line[term.ocy][term.ocx].mode & ATTR_WDUMMY)
+ term.ocx--;
+ if (term.line[term.c.y][cx].mode & ATTR_WDUMMY)
+ cx--;
+
+ drawregion(0, 0, term.col, term.row);
+ xdrawcursor(cx, term.c.y, term.line[term.c.y][cx],
+ term.ocx, term.ocy, term.line[term.ocy][term.ocx]);
+ term.ocx = cx;
+ term.ocy = term.c.y;
+ xfinishdraw();
+ if (ocx != term.ocx || ocy != term.ocy)
+ xximspot(term.ocx, term.ocy);
+}
+
+void
+redraw(void)
+{
+ tfulldirt();
+ draw();