+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, sizeof(vtiden) - 1);
+ break;
+ case 'c': /* RIS -- Reset to inital state */
+ treset();
+ resettitle();
+ xloadcols();
+ break;
+ case '=': /* DECPAM -- Application keypad */
+ term.mode |= MODE_APPKEYPAD;
+ break;
+ case '>': /* DECPNM -- Normal keypad */
+ term.mode &= ~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 (!IS_SET(MODE_UTF8) && !IS_SET(MODE_SIXEL)) {
+ c[0] = u;
+ width = len = 1;
+ } else {
+ len = utf8encode(u, c);
+ if (!control && (width = wcwidth(u)) == -1) {
+ memcpy(c, "\357\277\275", 4); /* UTF_INVALID */
+ 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|ESC_DCS);
+ if (IS_SET(MODE_SIXEL)) {
+ /* TODO: render sixel */;
+ term.mode &= ~MODE_SIXEL;
+ return;
+ }
+ term.esc |= ESC_STR_END;
+ goto check_control_code;
+ }
+
+
+ if (IS_SET(MODE_SIXEL)) {
+ /* TODO: implement sixel mode */
+ return;
+ }
+ if (term.esc&ESC_DCS && strescseq.len == 0 && u == 'q')
+ term.mode |= MODE_SIXEL;
+
+ if (strescseq.len+len >= sizeof(strescseq.buf)-1) {
+ /*
+ * 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();
+ */
+ return;
+ }
+
+ 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
+ */
+ 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 (sel.ob.x != -1 && BETWEEN(term.c.y, sel.ob.y, sel.oe.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);
+
+ 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;
+ }
+}
+
+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 width */
+ term.specbuf = xrealloc(term.specbuf, col * sizeof(GlyphFontSpec));
+
+ /* 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
+zoom(const Arg *arg)
+{
+ Arg larg;
+
+ larg.f = usedfontsize + arg->f;
+ zoomabs(&larg);
+}
+
+void
+zoomabs(const Arg *arg)
+{
+ xunloadfonts();
+ xloadfonts(usedfont, arg->f);
+ cresize(0, 0);
+ ttyresize();
+ redraw();
+ xhints();
+}
+
+void
+zoomreset(const Arg *arg)
+{
+ Arg larg;
+
+ if (defaultfontsize > 0) {
+ larg.f = defaultfontsize;
+ zoomabs(&larg);
+ }
+}
+
+void
+resettitle(void)
+{
+ xsettitle(opt_title ? opt_title : "st");
+}
+
+void
+redraw(void)
+{
+ tfulldirt();
+ draw();
+}
+
+int
+match(uint mask, uint state)
+{
+ return mask == XK_ANY_MOD || mask == (state & ~ignoremod);
+}
+
+void
+numlock(const Arg *dummy)
+{
+ term.numlock ^= 1;
+}
+
+char*
+kmap(KeySym k, uint state)
+{
+ Key *kp;
+ int i;
+
+ /* Check for mapped keys out of X11 function keys. */
+ for (i = 0; i < LEN(mappedkeys); i++) {
+ if (mappedkeys[i] == k)
+ break;
+ }
+ if (i == LEN(mappedkeys)) {
+ if ((k & 0xFFFF) < 0xFD00)
+ return NULL;
+ }
+
+ for (kp = key; kp < key + LEN(key); kp++) {
+ if (kp->k != k)
+ continue;
+
+ if (!match(kp->mask, state))
+ continue;
+
+ if (IS_SET(MODE_APPKEYPAD) ? kp->appkey < 0 : kp->appkey > 0)
+ continue;
+ if (term.numlock && kp->appkey == 2)
+ continue;
+
+ if (IS_SET(MODE_APPCURSOR) ? kp->appcursor < 0 : kp->appcursor > 0)
+ continue;
+
+ if (IS_SET(MODE_CRLF) ? kp->crlf < 0 : kp->crlf > 0)
+ continue;
+
+ return kp->s;
+ }
+
+ return NULL;
+}
+
+void
+cresize(int width, int height)
+{
+ int col, row;
+
+ if (width != 0)
+ win.w = width;
+ if (height != 0)
+ win.h = height;
+
+ col = (win.w - 2 * borderpx) / win.cw;
+ row = (win.h - 2 * borderpx) / win.ch;
+
+ tresize(col, row);
+ xresize(col, row);
+}
+
+void
+usage(void)
+{
+ die("usage: %s [-aiv] [-c class] [-f font] [-g geometry]"
+ " [-n name] [-o file]\n"
+ " [-T title] [-t title] [-w windowid]"
+ " [[-e] command [args ...]]\n"
+ " %s [-aiv] [-c class] [-f font] [-g geometry]"
+ " [-n name] [-o file]\n"
+ " [-T title] [-t title] [-w windowid] -l line"
+ " [stty_args ...]\n", argv0, argv0);