RLGWebD: termemu.js comparison

comparison termemu.js @ 211:d60063a674e1

Terminal emulation: implement the CSI b sequence. CSI b repeats the previous character, if it was printable and not an escape sequence.

author	John "Elwin" Edwards
date	Thu, 05 Sep 2019 15:19:27 -0400
parents	1d3cfe10974a
children

comparison

equal deleted inserted replaced

-:b04313038a0b
+:d60063a674e1
 bgColor: "black", // Default background color
 scrT: 0, // top and bottom of scrolling region
 scrB: 0, // init() will set this properly
 c: null,   // Contains cursor position and text attributes
 offedge: false, // Going off the edge doesn't mean adding a new line
+lastcode: 0, // Last printed character
 clearAttrs: function () {
 /* Make sure to reset ALL attribute properties and NOTHING else. */
 this.c.bold = false;
 this.c.inverse = false;
 this.c.uline = false;
 }
 for (var i = 0; i < this.h; i++) {
 this.screen.replaceChild(this.makeRow(), this.screen.childNodes[i]);
 }
 this.flipCursor(); // make it appear in the new row
+this.lastcode = 0;
 return;
 },
 write: function (codes) {
 //dchunk(codes);
 for (var i = 0; i < codes.length; i++) {
 }
 else {
 /* Nothing else is implemented yet. */
 debug(1, "Unrecognized sequence ESC " + codes[i].toString(16));
 this.comseq = [];
+}
+if (this.comseq.length == 0) {
+// A complete sequence was processed, clear lastcode.
+this.lastcode = 0;
 }
 }
 else if (this.comseq.length == 2 && this.comseq[0] == 27) {
 /* An ESC C N sequence.  Not implemented. Doesn't check validity
 * of N. */
 else
 debug(1, "Unknown sequence ESC " +
 String.fromCharCode(this.comseq[1]) + " 0x" +
 codes[i].toString(16));
 this.comseq = [];
+this.lastcode = 0;
 }
 else if (this.comseq[0] == 157) {
 /* Commands beginning with OSC */
 /* Check for string terminator */
 if (codes[i] == 7 || codes[i] == 156 || (codes[i] == 92 &&
 if (codes[i] == 92 && this.comseq[this.comseq.length - 1] == 27)
 this.comseq.pop();
 debug(0, "Got " + (this.comseq.length - 1) + "-byte OSC sequence");
 this.oscProcess();
 this.comseq = [];
+this.lastcode = 0;
 }
 else
 this.comseq.push(codes[i]);
 }
 else if (this.comseq[0] == 155) {
 if (csiPre.indexOf(codes[i]) >= 0) {
 if (this.comseq.length > 1) {
 /* Chars in csiPre can only occur right after the CSI */
 debug(1, "Invalid CSI sequence: misplaced prefix");
 this.comseq = [];
+this.lastcode = 0;
 }
 else
 this.comseq.push(codes[i]);
 }
 else if (csiPost.indexOf(this.comseq[this.comseq.length - 1]) >= 0 &&
 !csiFinal(codes[i])) {
-/* Chars is csiPost must come right before the final char */
+/* Chars in csiPost must come right before the final char */
 debug(1, "Invalid CSI sequence: misplaced postfix");
 this.comseq = [];
+this.lastcode = 0;
 }
 else if ((codes[i] >= 48 && codes[i] <= 57) || codes[i] == 59 ||
 csiPost.indexOf(codes[i]) >= 0) {
 /* Numbers and ; can go anywhere */
 this.comseq.push(codes[i]);
 this.comseq = [];
 }
 else {
 debug(1, "Invalid CSI sequence: unknown code " + codes[i].toString(16));
 this.comseq = [];
+this.lastcode = 0;
 }
 }
 else {
 debug(1, "Unknown sequence with " + this.comseq[0].toString(16));
 this.comseq = [];
-}
+this.lastcode = 0;
-continue;
+}
 }
-/* Treat it as a single character. */
+else if ((codes[i] >= 32 && codes[i] < 127) || codes[i] >= 160) {
-if (codes[i] == 5) {
-sendback("06");
-}
-else if (codes[i] == 7) {
-/* bell */
-bell(true);
-}
-else if (codes[i] == 8) {
-/* backspace */
-if (this.offedge)
-this.offedge = false;
-else if (this.c.x > 0)
-this.cmove(null, this.c.x - 1);
-}
-else if (codes[i] == 9) {
-/* tab */
-var xnew;
-if (this.c.x < this.w - 1) {
-xnew = 8 * (Math.floor(this.c.x / 8) + 1);
-if (xnew >= this.w)
-xnew = this.w - 1;
-this.cmove(null, xnew);
-}
-else {
-this.offedge = true;
-}
-}
-else if (codes[i] >= 10 && codes[i] <= 12) {
-/* newline, vertical tab, form feed */
-if (this.offedge)
-this.newline(true);
-else
-this.newline(false);
-}
-else if (codes[i] == 13) {
-/* carriage return \r */
-this.cmove(null, 0);
-}
-else if (codes[i] == 14) {
-/* shift out */
-// Currently assuming that G1 is DEC Special & Line Drawing
-this.c.cset = "0";
-debug(0, "Using DEC graphics charset.");
-}
-else if (codes[i] == 15) {
-/* shift in */
-// Currently assuming that G0 is ASCII
-this.c.cset = "B";
-debug(0, "Using ASCII charset.");
-}
-else if (codes[i] == 27) {
-/* escape */
-this.comseq.push(codes[i]);
-}
-else if (codes[i] < 32 || (codes[i] >= 127 && codes[i] < 160)) {
-/* Some kind of control character. */
-debug(1, "Unprintable character 0x" + codes[i].toString(16));
-}
-else {
 /* If it's ASCII, it's printable; take a risk on anything higher */
 if ((this.c.cset == "0") && (codes[i] in decChars)) {
 // DEC special character set
-this.placechar(String.fromCharCode(decChars[codes[i]]));
+this.lastcode = decChars[codes[i]];
 }
 else {
-this.placechar(String.fromCharCode(codes[i]));
+this.lastcode = codes[i];
 }
+this.placechar(String.fromCharCode(this.lastcode));
+}
+else {
+/* Treat it as a single control character. */
+this.singleCtl(codes[i]);
 }
 }
 return;
+},
+singleCtl: function (ctlcode) {
+if (ctlcode == 5) {
+sendback("06");
+}
+else if (ctlcode == 7) {
+/* bell */
+bell(true);
+}
+else if (ctlcode == 8) {
+/* backspace */
+if (this.offedge)
+this.offedge = false;
+else if (this.c.x > 0)
+this.cmove(null, this.c.x - 1);
+}
+else if (ctlcode == 9) {
+/* tab */
+var xnew;
+if (this.c.x < this.w - 1) {
+xnew = 8 * (Math.floor(this.c.x / 8) + 1);
+if (xnew >= this.w)
+xnew = this.w - 1;
+this.cmove(null, xnew);
+}
+else {
+this.offedge = true;
+}
+}
+else if (ctlcode >= 10 && ctlcode <= 12) {
+/* newline, vertical tab, form feed */
+if (this.offedge)
+this.newline(true);
+else
+this.newline(false);
+}
+else if (ctlcode == 13) {
+/* carriage return \r */
+this.cmove(null, 0);
+}
+else if (ctlcode == 14) {
+/* shift out */
+// Currently assuming that G1 is DEC Special & Line Drawing
+this.c.cset = "0";
+debug(0, "Using DEC graphics charset.");
+}
+else if (ctlcode == 15) {
+/* shift in */
+// Currently assuming that G0 is ASCII
+this.c.cset = "B";
+debug(0, "Using ASCII charset.");
+}
+else if (ctlcode == 27) {
+/* escape */
+this.comseq.push(27);
+}
+else {
+debug(1, "Unprintable character 0x" + ctlcode.toString(16));
+}
+if (ctlcode != 27) {
+// Sequences should preserve lastcode until they are completed
+this.lastcode = 0;
+}
 },
 csiProcess: function () {
 /* Processes the CSI sequence in this.comseq */
 var c = this.comseq[this.comseq.length - 1];
 if (this.comseq[0] != 155 || !csiFinal(c))
 return;
+var printed = false;
 var comstr = "";
 for (var i = 1; i < this.comseq.length; i++)
 comstr += String.fromCharCode(this.comseq[i]);
 debug(0, "CSI sequence: " + comstr);
 var reCSI = /^([>?!])?([0-9;]*)([ "$'])?([A-Za-z@`{|])$/;
 var matchCSI = comstr.match(reCSI);
 if (!matchCSI) {
 debug(1, "Unrecognized CSI sequence: " + comstr);
+this.lastcode = 0;
 return;
 }
 var prefix = null;
 if (matchCSI[1])
 prefix = matchCSI[1];
 /* The final character determines the action. */
 if (c == 64) {
 /* @ - insert spaces at cursor */
 if (prefix || postfix) {
 debug(1, "Invalid CSI @ sequence: " + comstr);
+this.lastcode = 0;
 return;
 }
 /* The cursor stays still, but characters move out from under it. */
 this.flipCursor();
 var rowdiv = this.screen.childNodes[this.c.y];
 else if (c >= 65 && c <= 71) {
 /* A - up, B - down, C - forward, D - backward */
 /* E - next line, F - previous line, G - to column */
 if (prefix || postfix) {
 debug(1, "Invalid CSI sequence: " + comstr);
+this.lastcode = 0;
 return;
 }
 /* These may be out of range, but cmove will take care of that. */
 if (c == 65)
 this.cmove(this.c.y - count, null);
 /* H - move */
 var x = 0;
 var y = 0;
 if (prefix || postfix) {
 debug(1, "Invalid CSI H sequence: " + comstr);
+this.lastcode = 0;
 return;
 }
 if (params[0])
 y = params[0] - 1;
 if (params[1])
 else if (c == 73) {
 /* I - move forward by tabs */
 var x = this.c.x;
 if (prefix || postfix) {
 debug(1, "Invalid CSI I sequence: " + comstr);
+this.lastcode = 0;
 return;
 }
 while (count > 0) {
 x = 8 * (Math.floor(x / 8) + 1);
 if (x >= this.w) {
 var cols;
 if (prefix == '?')
 debug(1, "Warning: CSI ?J not implemented");
 else if (prefix || postfix) {
 debug(1, "Invalid CSI J sequence: " + comstr);
+this.lastcode = 0;
 return;
 }
 if (!params[0]) {
 /* Either 0 or not given */
 start = this.c.y + 1;
 end = this.h - 1;
 cols = 0;
 }
 else {