js/term.js - emulators/tinyemu - Rivoreo Source Code Repositories

 /*
  * Javascript terminal
  *
  * Copyright (c) 2011 Fabrice Bellard
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
 "use strict";

 function Term(width, height, handler, tot_height)
 {
     this.w = width;
     this.h = height;

     this.cur_h = height; /* current height of the scroll back buffer */
     if (!tot_height || tot_height < height)
         tot_height = height;
     this.tot_h = tot_height; /* maximum height of the scroll back buffer */
     this.y_base = 0; /* position of the current top screen line in the
                       * scroll back buffer */
     this.y_disp = 0; /* position of the top displayed line in the
                       * scroll back buffer */
     /* cursor position */
     this.x = 0;
     this.y = 0;
     this.cursorstate = 0;
     this.handler = handler;
     this.state = 0;
     this.output_queue = "";
     this.bg_colors = [
         "#000000",
         "#ff0000",
         "#00ff00",
         "#ffff00",
         "#0000ff",
         "#ff00ff",
         "#00ffff",
         "#ffffff"
     ];
     this.fg_colors = [
         "#000000",
         "#ff0000",
         "#00ff00",
         "#ffff00",
         "#0000ff",
         "#ff00ff",
         "#00ffff",
         "#ffffff"
     ];
     this.def_attr = (7 << 3) | 0;
     this.cur_attr = this.def_attr;
     this.is_mac = (navigator.userAgent.indexOf("Mac") >=0 ) ? true : false;
     this.key_rep_state = 0;
     this.key_rep_str = "";
 }

 Term.prototype.open = function(parent_el, textarea_el)
 {
     var y, line, i, term, c, row_el;

     /* set initial content */
     this.lines = new Array();
     c = 32 | (this.def_attr << 16);
     for(y = 0; y < this.cur_h;y++) {
         line = new Array();
         for(i=0;i<this.w;i++)
             line[i] = c;
         this.lines[y] = line;
     }

     /* create the terminal window */
     this.term_el = document.createElement("div");
     this.term_el.className = "term";
     this.term_el.style.lineHeight = "1.2em";
     /* XXX: could compute the font metrics */
     this.term_el.style.width = "calc(" + this.w + "ch + 16px)";
     this.term_el.style.height = (this.h * 1.2) + "em";

     /* scroll bar */
     this.scrollbar_el = document.createElement("div");
     this.scrollbar_el.className = "term_scrollbar";
     this.term_el.appendChild(this.scrollbar_el);

     this.track_el = document.createElement("div");
     this.track_el.className = "term_track";
     this.track_el.onmousedown = this.mouseMoveHandler.bind(this);
     this.scrollbar_el.appendChild(this.track_el);

     this.thumb_el = document.createElement("div");
     this.thumb_el.className = "term_thumb";
     this.thumb_el.onmousedown = this.mouseDownHandler.bind(this);
     this.track_el.appendChild(this.thumb_el);

     this.end_el = document.createElement("div");
     this.end_el.className = "term_end";
     this.thumb_el.appendChild(this.end_el);

     /* current scrollbar position */
     this.thumb_size = -1;
     this.thumb_pos = -1;

     /* terminal content */
     this.content_el = document.createElement("div");
     this.content_el.className = "term_content";
     this.content_el.style.width = (this.w) + "ch";
     this.term_el.appendChild(this.content_el);

     this.rows_el = [];
     for(y=0;y<this.h;y++) {
         row_el = document.createElement("div");
         this.rows_el.push(row_el);
         this.content_el.appendChild(row_el);
     }

     this.parent_el = parent_el;
     parent_el.appendChild(this.term_el);

     /* dummy text area for copy paste & mobile devices */
     this.textarea_el = textarea_el;

     this.refresh(0, this.h - 1);

     // key handler
     document.addEventListener("keydown",
                               this.keyDownHandler.bind(this), true);
     document.addEventListener("keypress",
                               this.keyPressHandler.bind(this), true);
     // wheel
     document.addEventListener("wheel",
                               this.wheelHandler.bind(this), false);
     // paste
     document.defaultView.addEventListener("paste",
                                           this.pasteHandler.bind(this), false);

     // cursor blinking
     term = this;
     setInterval(function() { term.cursor_timer_cb(); }, 1000);
 };

 Term.prototype.refresh_scrollbar = function ()
 {
     var total_size, thumb_pos, thumb_size, y, y0;
     total_size = this.term_el.clientHeight;
     thumb_size = Math.ceil(this.h * total_size / this.cur_h);
     /* position of the first line of the scroll back buffer */
     y0 = (this.y_base + this.h) % this.cur_h;
     y = this.y_disp - y0;
     if (y < 0)
         y += this.cur_h;
     thumb_pos = Math.floor(y * total_size / this.cur_h);
     thumb_size = Math.max(thumb_size, 30);
     thumb_size = Math.min(thumb_size, total_size);
     thumb_pos = Math.min(thumb_pos, total_size - thumb_size);
 //    console.log("pos=" + thumb_pos + " size=" + thumb_size);
     if (thumb_pos != this.thumb_pos || thumb_size != this.thumb_size) {
         this.thumb_pos = thumb_pos;
         this.thumb_size = thumb_size;
         this.thumb_el.style.top = thumb_pos + "px";
         this.thumb_el.style.height = thumb_size + "px";
     }
 }

 Term.prototype.refresh = function(ymin, ymax)
 {
     var el, y, line, outline, c, w, i, j, cx, attr, last_attr, fg, bg, y1;
     var http_link_len, http_link_str;

     function is_http_link_char(c)
     {
         var str = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~:/?#[]@!$&'()*+,;=`.";
         return str.indexOf(String.fromCharCode(c)) >= 0;
     }

     function right_trim(str, a)
     {
         var i, n;
         n = a.length;
         i = str.length;
         while (i >= n && str.substr(i - n, n) == a)
             i -= n;
         return str.substr(0, i);
     }

     for(y = ymin; y <= ymax; y++) {
         /* convert to HTML string */
         y1 = y + this.y_disp;
         if (y1 >= this.cur_h)
             y1 -= this.cur_h;
         line = this.lines[y1];
         outline = "";
         w = this.w;
         if (y == this.y && this.cursor_state &&
             this.y_disp == this.y_base) {
             cx = this.x;
         } else {
             cx = -1;
         }
         last_attr = this.def_attr;
         http_link_len = 0;
         for(i = 0; i < w; i++) {
             c = line[i];
             attr = c >> 16;
             c &= 0xffff;
             /* test for http link */
             if (c == 0x68 && (w - i) >= 8 && http_link_len == 0) {
                 /* test http:// or https:// */
                 if ((line[i + 1] & 0xffff) == 0x74 &&
                     (line[i + 2] & 0xffff) == 0x74 &&
                     (line[i + 3] & 0xffff) == 0x70 &&
                     (((line[i + 4] & 0xffff) == 0x3a &&
                       (line[i + 5] & 0xffff) == 0x2f &&
                       (line[i + 6] & 0xffff) == 0x2f) ||
                      ((line[i + 4] & 0xffff) == 0x73 &&
                       (line[i + 5] & 0xffff) == 0x3a &&
                       (line[i + 6] & 0xffff) == 0x2f &&
                       (line[i + 7] & 0xffff) == 0x2f))) {
                     http_link_str = "";
                     j = 0;
                     while ((i + j) < w &&
                            is_http_link_char(line[i + j] & 0xffff)) {
                         http_link_str += String.fromCharCode(line[i + j] & 0xffff);
                         j++;
                     }
                     http_link_len = j;
                     if (last_attr != this.def_attr) {
                         outline += '</span>';
                         last_attr = this.def_attr;
                     }
                     outline += "<a href='" + http_link_str + "'>";
                 }
             }
             if (i == cx)  {
                 attr = -1; /* cursor */
             }
             if (attr != last_attr) {
                 if (last_attr != this.def_attr)
                     outline += '</span>';
                 if (attr != this.def_attr) {
                     if (attr == -1) {
                         /* cursor */
                         outline += '<span class="term_cursor">';
                     } else {
                         outline += '<span style="';
                         fg = (attr >> 3) & 7;
                         bg = attr & 7;
                         if (fg != 7) {
                             outline += 'color:' + this.fg_colors[fg] + ';';
                         }
                         if (bg != 0) {
                             outline += 'background-color:' +
                                 this.bg_colors[bg] + ';';
                         }
                         outline += '">';
                     }
                 }
             }
             switch(c) {
             case 32:
                 outline += "&nbsp;";
                 break;
             case 38: // '&'
                 outline += "&amp;";
                 break;
             case 60: // '<'
                 outline += "&lt;";
                 break;
             case 62: // '>'
                 outline += "&gt;";
                 break;
             default:
                 if (c < 32) {
                     outline += "&nbsp;";
                 } else {
                     outline += String.fromCharCode(c);
                 }
                 break;
             }
             last_attr = attr;
             if (http_link_len != 0) {
                 http_link_len--;
                 if (http_link_len == 0) {
                     if (last_attr != this.def_attr) {
                         outline += '</span>';
                         last_attr = this.def_attr;
                     }
                     outline += "</a>";
                 }
             }
         }
         if (last_attr != this.def_attr) {
             outline += '</span>';
         }

         /* trim trailing spaces for copy/paste */
         outline = right_trim(outline, "&nbsp;");
         if (outline == "")
             outline = "&nbsp;";

         this.rows_el[y].innerHTML = outline;
     }

     this.refresh_scrollbar();
 };

 Term.prototype.cursor_timer_cb = function()
 {
     this.cursor_state ^= 1;
     this.refresh(this.y, this.y);
 };

 Term.prototype.show_cursor = function()
 {
     if (!this.cursor_state) {
         this.cursor_state = 1;
         this.refresh(this.y, this.y);
     }
 };

 Term.prototype.scroll = function()
 {
     var y, line, x, c, y1;

     /* increase height of buffer if possible */
     if (this.cur_h < this.tot_h) {
         this.cur_h++;
     }
     /* move down one line */
     if (++this.y_base == this.cur_h)
         this.y_base = 0;
     this.y_disp = this.y_base;

     c = 32 | (this.def_attr << 16);
     line = new Array();
     for(x=0;x<this.w;x++)
         line[x] = c;
     y1 = this.y_base + this.h - 1;
     if (y1 >= this.cur_h)
         y1 -= this.cur_h;
     this.lines[y1] = line;
 };

 /* scroll down or up in the scroll back buffer by n lines */
 Term.prototype.scroll_disp = function(n)
 {
     var i, y1;
     /* slow but it does not really matters */
     if (n >= 0) {
         for(i = 0; i < n; i++) {
             if (this.y_disp == this.y_base)
                 break;
             if (++this.y_disp == this.cur_h)
                 this.y_disp = 0;
         }
     } else {
         n = -n;
         y1 = this.y_base + this.h;
         if (y1 >= this.cur_h)
             y1 -= this.cur_h;
         for(i = 0; i < n; i++) {
             if (this.y_disp == y1)
                 break;
             if (--this.y_disp < 0)
                 this.y_disp = this.cur_h - 1;
         }
     }
     this.refresh(0, this.h - 1);
 };

 Term.prototype.write = function(str)
 {
     function update(y)
     {
         ymin = Math.min(ymin, y);
         ymax = Math.max(ymax, y);
     }

     function erase_to_eol(s, x, y)
     {
         var l, i, c, y1;
         y1 = s.y_base + y;
         if (y1 >= s.cur_h)
             y1 -= s.cur_h;
         l = s.lines[y1];
         c = 32 | (s.def_attr << 16);
         for(i = x; i < s.w; i++)
             l[i] = c;
         update(y);
     }

     function csi_colors(s, esc_params)
     {
         var j, n, fg, bg;

         if (esc_params.length == 0) {
             s.cur_attr= s.def_attr;
         } else {
             for(j = 0; j < esc_params.length; j++) {
                 n = esc_params[j];
                 if (n >= 30 && n <= 37) {
                     /* foreground */
                     fg = n - 30;
                     s.cur_attr = (s.cur_attr & ~(7 << 3)) | (fg << 3);
                 } else if (n >= 40 && n <= 47) {
                     /* background */
                     bg = n - 40;
                     s.cur_attr = (s.cur_attr & ~7) | bg;
                 } else if (n >= 90 && n <= 97) {
                     /* foreground (XXX: 16 color table) */
                     fg = n - 90;
                     s.cur_attr = (s.cur_attr & ~(7 << 3)) | (fg << 3);
                 } else if (n >= 100 && n <= 107) {
                     /* background (XXX: 16 color table) */
                     bg = n - 100;
                     s.cur_attr = (s.cur_attr & ~7) | bg;
                 } else if (n == 0) {
                     /* default attr */
                     s.cur_attr = s.def_attr;
                 }
             }
         }
     }

     var TTY_STATE_NORM = 0;
     var TTY_STATE_ESC = 1;
     var TTY_STATE_CSI = 2;
     var TTY_STATE_CHARSET = 3;

     var i, c, ymin, ymax, l, n, j, y1;

     /* update region is in ymin ymax */
     ymin = this.h;
     ymax = -1;
     update(this.y); // remove the cursor
     /* reset top of displayed screen to top of real screen */
     if (this.y_base != this.y_disp) {
         this.y_disp = this.y_base;
         /* force redraw */
         ymin = 0;
         ymax = this.h - 1;
     }
     for(i = 0; i < str.length; i++) {
         c = str.charCodeAt(i);
         switch(this.state) {
         case TTY_STATE_NORM:
             switch(c) {
             case 10:
                 this.y++;
                 if (this.y >= this.h) {
                     this.y--;
                     this.scroll();
                     ymin = 0;
                     ymax = this.h - 1;
                 }
                 break;
             case 13:
                 this.x = 0;
                 break;
             case 8:
                 if (this.x > 0) {
                     this.x--;
                 }
                 break;
             case 9: /* tab */
                 n = (this.x + 8) & ~7;
                 if (n <= this.w) {
                     this.x = n;
                 }
                 break;
             case 27:
                 this.state = TTY_STATE_ESC;
                 break;
             default:
                 if (c >= 32) {
                     if (this.x >= this.w) {
                         this.x = 0;
                         this.y++;
                         if (this.y >= this.h) {
                             this.y--;
                             this.scroll();
                             ymin = 0;
                             ymax = this.h - 1;
                         }
                     }
                     y1 = this.y + this.y_base;
                     if (y1 >= this.cur_h)
                         y1 -= this.cur_h;
                     this.lines[y1][this.x] = (c & 0xffff) |
                         (this.cur_attr << 16);
                     this.x++;
                     update(this.y);
                 }
                 break;
             }
             break;
         case TTY_STATE_ESC:
             switch(c) {
             case 91: // '['
                 this.esc_params = new Array();
                 this.cur_param = 0;
                 this.state = TTY_STATE_CSI;
                 break;
             case 40: // '('
             case 41: // ')'
                 this.state = TTY_STATE_CHARSET;
                 break;
             default:
                 this.state = TTY_STATE_NORM;
                 break;
             }
             break;
         case TTY_STATE_CSI:
             if (c >= 48 && c <= 57) { // '0' '9'
                 /* numeric */
                 this.cur_param = this.cur_param * 10 + c - 48;
             } else {
                 if (c == 63) // '?'
                     break; /* ignore prefix */
                 /* add parsed parameter */
                 this.esc_params[this.esc_params.length] = this.cur_param;
                 this.cur_param = 0;
                 if (c == 59) // ;
                     break;
                 this.state = TTY_STATE_NORM;

                 //                console.log("term: csi=" + this.esc_params + " cmd="+c);
                 switch(c) {
                 case 65: // 'A' up
                     n = this.esc_params[0];
                     if (n < 1)
                         n = 1;
                     this.y -= n;
                     if (this.y < 0)
                         this.y = 0;
                     break;
                 case 66: // 'B' down
                     n = this.esc_params[0];
                     if (n < 1)
                         n = 1;
                     this.y += n;
                     if (this.y >= this.h)
                         this.y = this.h - 1;
                     break;
                 case 67: // 'C' right
                     n = this.esc_params[0];
                     if (n < 1)
                         n = 1;
                     this.x += n;
                     if (this.x >= this.w - 1)
                         this.x = this.w - 1;
                     break;
                 case 68: // 'D' left
                     n = this.esc_params[0];
                     if (n < 1)
                         n = 1;
                     this.x -= n;
                     if (this.x < 0)
                         this.x = 0;
                     break;

                 case 72: // 'H' goto xy
                     {
                         var x1, y1;
                         y1 = this.esc_params[0] - 1;
                         if (this.esc_params.length >= 2)
                             x1 = this.esc_params[1] - 1;
                         else
                             x1 = 0;
                         if (y1 < 0)
                             y1 = 0;
                         else if (y1 >= this.h)
                             y1 = this.h - 1;
                         if (x1 < 0)
                             x1 = 0;
                         else if (x1 >= this.w)
                             x1 = this.w - 1;
                         this.x = x1;
                         this.y = y1;
                     }
                     break;
                 case 74: // 'J' erase to end of screen
                     erase_to_eol(this, this.x, this.y);
                     for(j = this.y + 1; j < this.h; j++)
                         erase_to_eol(this, 0, j);
                     break;
                 case 75: // 'K' erase to end of line
                     erase_to_eol(this, this.x, this.y);
                     break;
                 case 109: // 'm': set color
                     csi_colors(this, this.esc_params);
                     break;
                 case 110: // 'n' return the cursor position
                     this.queue_chars("\x1b[" + (this.y + 1) + ";" + (this.x + 1) + "R");
                     break;
                 default:
                     break;
                 }
             }
             break;
         case TTY_STATE_CHARSET:
             /* just ignore */
             this.state = TTY_STATE_NORM;
             break;
         }
     }
     update(this.y); // show the cursor

     if (ymax >= ymin)
         this.refresh(ymin, ymax);
 };

 Term.prototype.writeln = function (str)
 {
     this.write(str + '\r\n');
 };

 Term.prototype.keyDownHandler = function (ev)
 {
     var str;

     str="";
     switch(ev.keyCode) {
     case 8: /* backspace */
         str = "\x7f";
         break;
     case 9: /* tab */
         str = "\x09";
         break;
     case 13: /* enter */
         str = "\x0d";
         break;
     case 27: /* escape */
         str = "\x1b";
         break;
     case 37: /* left */
         str = "\x1b[D";
         break;
     case 39: /* right */
         str = "\x1b[C";
         break;
     case 38: /* up */
         if (ev.ctrlKey) {
             this.scroll_disp(-1);
         } else {
             str = "\x1b[A";
         }
         break;
     case 40: /* down */
         if (ev.ctrlKey) {
             this.scroll_disp(1);
         } else {
             str = "\x1b[B";
         }
         break;
     case 46: /* delete */
         str = "\x1b[3~";
         break;
     case 45: /* insert */
         str = "\x1b[2~";
         break;
     case 36: /* home */
         str = "\x1bOH";
         break;
     case 35: /* end */
         str = "\x1bOF";
         break;
     case 33: /* page up */
         if (ev.ctrlKey) {
             this.scroll_disp(-(this.h - 1));
         } else {
             str = "\x1b[5~";
         }
         break;
     case 34: /* page down */
         if (ev.ctrlKey) {
             this.scroll_disp(this.h - 1);
         } else {
             str = "\x1b[6~";
         }
         break;
     default:
         if (ev.ctrlKey) {
             /* ctrl + key */
             if (ev.keyCode >= 65 && ev.keyCode <= 90) {
                 str = String.fromCharCode(ev.keyCode - 64);
             } else if (ev.keyCode == 32) {
                 str = String.fromCharCode(0);
             }
         } else if ((!this.is_mac && ev.altKey) ||
                    (this.is_mac && ev.metaKey)) {
             /* meta + key (Note: we only send lower case) */
             if (ev.keyCode >= 65 && ev.keyCode <= 90) {
                 str = "\x1b" + String.fromCharCode(ev.keyCode + 32);
             }
         }
         break;
     }
     //    console.log("keydown: keycode=" + ev.keyCode + " charcode=" + ev.charCode + " str=" + str + " ctrl=" + ev.ctrlKey + " alt=" + ev.altKey + " meta=" + ev.metaKey);
     if (str) {
         if (ev.stopPropagation)
             ev.stopPropagation();
         if (ev.preventDefault)
             ev.preventDefault();

         this.show_cursor();
         this.key_rep_state = 1;
         this.key_rep_str = str;
         this.handler(str);
         return false;
     } else {
         this.key_rep_state = 0;
         return true;
     }
 };

 Term.prototype.keyPressHandler = function (ev)
 {
     var str, char_code;

     if (ev.stopPropagation)
         ev.stopPropagation();
     if (ev.preventDefault)
         ev.preventDefault();

     str="";
     if (!("charCode" in ev)) {
         /* on Opera charCode is not defined and keypress is sent for
          system keys. Moreover, only keupress is repeated which is a
          problem for system keys. */
         char_code = ev.keyCode;
         if (this.key_rep_state == 1) {
             this.key_rep_state = 2;
             return false;
         } else if (this.key_rep_state == 2) {
             /* repetition */
             this.show_cursor();
             this.handler(this.key_rep_str);
             return false;
         }
     } else {
         char_code = ev.charCode;
     }
     if (char_code != 0) {
         if (!ev.ctrlKey &&
             ((!this.is_mac && !ev.altKey) ||
              (this.is_mac && !ev.metaKey))) {
             str = String.fromCharCode(char_code);
         }
     }
     //    console.log("keypress: keycode=" + ev.keyCode + " charcode=" + ev.charCode + " str=" + str + " ctrl=" + ev.ctrlKey + " alt=" + ev.altKey + " meta=" + ev.metaKey);
     if (str) {
         this.show_cursor();
         this.handler(str);
         return false;
     } else {
         return true;
     }
 };

 Term.prototype.wheelHandler = function (ev)
 {
     if (ev.deltaY < 0)
         this.scroll_disp(-3);
     else if (ev.deltaY > 0)
         this.scroll_disp(3);
     ev.stopPropagation();
 }

 Term.prototype.mouseDownHandler = function (ev)
 {
     this.thumb_el.onmouseup = this.mouseUpHandler.bind(this);
     document.onmousemove = this.mouseMoveHandler.bind(this);
     document.onmouseup = this.mouseUpHandler.bind(this);

     /* disable potential selection */
     document.body.className += " noSelect";

     this.mouseMoveHandler(ev);
 }

 Term.prototype.mouseMoveHandler = function (ev)
 {
     var total_size, pos, new_y_disp, y, y0;
     total_size = this.term_el.clientHeight;
     y = ev.clientY - this.track_el.getBoundingClientRect().top;
     pos = Math.floor((y - (this.thumb_size / 2)) * this.cur_h / total_size);
     new_y_disp = Math.min(Math.max(pos, 0), this.cur_h - this.h);
     /* position of the first line of the scroll back buffer */
     y0 = (this.y_base + this.h) % this.cur_h;
     new_y_disp += y0;
     if (new_y_disp >= this.cur_h)
         new_y_disp -= this.cur_h;
     if (new_y_disp != this.y_disp) {
         this.y_disp = new_y_disp;
         this.refresh(0, this.h - 1);
     }
 }

 Term.prototype.mouseUpHandler = function (ev)
 {
     this.thumb_el.onmouseup = null;
     document.onmouseup = null;
     document.onmousemove = null;
     document.body.className = document.body.className.replace(" noSelect", "");
 }

 Term.prototype.pasteHandler = function (ev)
 {
     var c = ev.clipboardData;
     if (c) {
         this.queue_chars(c.getData("text/plain"));
         setTimeout(this.textAreaReset.bind(this), 10);
         return false;
     }
 }

 Term.prototype.textAreaReset = function(ev)
 {
     /* reset text */
     this.textarea_el.value = "Paste Here";
 }

 /* output queue to send back asynchronous responses */
 Term.prototype.queue_chars = function (str)
 {
     this.output_queue += str;
     if (this.output_queue)
         setTimeout(this.outputHandler.bind(this), 0);
 };

 Term.prototype.outputHandler = function ()
 {
     if (this.output_queue) {
         this.handler(this.output_queue);
         this.output_queue = "";
     }
 };

 Term.prototype.getSize = function ()
 {
     return [this.w, this.h];
 };
	/*
	* Javascript terminal
	*
	* Copyright (c) 2011 Fabrice Bellard
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	* THE SOFTWARE.
	*/
	"use strict";

	function Term(width, height, handler, tot_height)
	{
	this.w = width;
	this.h = height;

	this.cur_h = height; /* current height of the scroll back buffer */
	if (!tot_height \|\| tot_height < height)
	tot_height = height;
	this.tot_h = tot_height; /* maximum height of the scroll back buffer */
	this.y_base = 0; /* position of the current top screen line in the
	* scroll back buffer */
	this.y_disp = 0; /* position of the top displayed line in the
	* scroll back buffer */
	/* cursor position */
	this.x = 0;
	this.y = 0;
	this.cursorstate = 0;
	this.handler = handler;
	this.state = 0;
	this.output_queue = "";
	this.bg_colors = [
	"#000000",
	"#ff0000",
	"#00ff00",
	"#ffff00",
	"#0000ff",
	"#ff00ff",
	"#00ffff",
	"#ffffff"
	];
	this.fg_colors = [
	"#000000",
	"#ff0000",
	"#00ff00",
	"#ffff00",
	"#0000ff",
	"#ff00ff",
	"#00ffff",
	"#ffffff"
	];
	this.def_attr = (7 << 3) \| 0;
	this.cur_attr = this.def_attr;
	this.is_mac = (navigator.userAgent.indexOf("Mac") >=0 ) ? true : false;
	this.key_rep_state = 0;
	this.key_rep_str = "";
	}

	Term.prototype.open = function(parent_el, textarea_el)
	{
	var y, line, i, term, c, row_el;

	/* set initial content */
	this.lines = new Array();
	c = 32 \| (this.def_attr << 16);
	for(y = 0; y < this.cur_h;y++) {
	line = new Array();
	for(i=0;i<this.w;i++)
	line[i] = c;
	this.lines[y] = line;
	}

	/* create the terminal window */
	this.term_el = document.createElement("div");
	this.term_el.className = "term";
	this.term_el.style.lineHeight = "1.2em";
	/* XXX: could compute the font metrics */
	this.term_el.style.width = "calc(" + this.w + "ch + 16px)";
	this.term_el.style.height = (this.h * 1.2) + "em";

	/* scroll bar */
	this.scrollbar_el = document.createElement("div");
	this.scrollbar_el.className = "term_scrollbar";
	this.term_el.appendChild(this.scrollbar_el);

	this.track_el = document.createElement("div");
	this.track_el.className = "term_track";
	this.track_el.onmousedown = this.mouseMoveHandler.bind(this);
	this.scrollbar_el.appendChild(this.track_el);

	this.thumb_el = document.createElement("div");
	this.thumb_el.className = "term_thumb";
	this.thumb_el.onmousedown = this.mouseDownHandler.bind(this);
	this.track_el.appendChild(this.thumb_el);

	this.end_el = document.createElement("div");
	this.end_el.className = "term_end";
	this.thumb_el.appendChild(this.end_el);

	/* current scrollbar position */
	this.thumb_size = -1;
	this.thumb_pos = -1;

	/* terminal content */
	this.content_el = document.createElement("div");
	this.content_el.className = "term_content";
	this.content_el.style.width = (this.w) + "ch";
	this.term_el.appendChild(this.content_el);

	this.rows_el = [];
	for(y=0;y<this.h;y++) {
	row_el = document.createElement("div");
	this.rows_el.push(row_el);
	this.content_el.appendChild(row_el);
	}

	this.parent_el = parent_el;
	parent_el.appendChild(this.term_el);

	/* dummy text area for copy paste & mobile devices */
	this.textarea_el = textarea_el;

	this.refresh(0, this.h - 1);

	// key handler
	document.addEventListener("keydown",
	this.keyDownHandler.bind(this), true);
	document.addEventListener("keypress",
	this.keyPressHandler.bind(this), true);
	// wheel
	document.addEventListener("wheel",
	this.wheelHandler.bind(this), false);
	// paste
	document.defaultView.addEventListener("paste",
	this.pasteHandler.bind(this), false);

	// cursor blinking
	term = this;
	setInterval(function() { term.cursor_timer_cb(); }, 1000);
	};

	Term.prototype.refresh_scrollbar = function ()
	{
	var total_size, thumb_pos, thumb_size, y, y0;
	total_size = this.term_el.clientHeight;
	thumb_size = Math.ceil(this.h * total_size / this.cur_h);
	/* position of the first line of the scroll back buffer */
	y0 = (this.y_base + this.h) % this.cur_h;
	y = this.y_disp - y0;
	if (y < 0)
	y += this.cur_h;
	thumb_pos = Math.floor(y * total_size / this.cur_h);
	thumb_size = Math.max(thumb_size, 30);
	thumb_size = Math.min(thumb_size, total_size);
	thumb_pos = Math.min(thumb_pos, total_size - thumb_size);
	// console.log("pos=" + thumb_pos + " size=" + thumb_size);
	if (thumb_pos != this.thumb_pos \|\| thumb_size != this.thumb_size) {
	this.thumb_pos = thumb_pos;
	this.thumb_size = thumb_size;
	this.thumb_el.style.top = thumb_pos + "px";
	this.thumb_el.style.height = thumb_size + "px";
	}
	}

	Term.prototype.refresh = function(ymin, ymax)
	{
	var el, y, line, outline, c, w, i, j, cx, attr, last_attr, fg, bg, y1;
	var http_link_len, http_link_str;

	function is_http_link_char(c)
	{
	var str = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~:/?#[]@!$&'()*+,;=`.";
	return str.indexOf(String.fromCharCode(c)) >= 0;
	}

	function right_trim(str, a)
	{
	var i, n;
	n = a.length;
	i = str.length;
	while (i >= n && str.substr(i - n, n) == a)
	i -= n;
	return str.substr(0, i);
	}

	for(y = ymin; y <= ymax; y++) {
	/* convert to HTML string */
	y1 = y + this.y_disp;
	if (y1 >= this.cur_h)
	y1 -= this.cur_h;
	line = this.lines[y1];
	outline = "";
	w = this.w;
	if (y == this.y && this.cursor_state &&
	this.y_disp == this.y_base) {
	cx = this.x;
	} else {
	cx = -1;
	}
	last_attr = this.def_attr;
	http_link_len = 0;
	for(i = 0; i < w; i++) {
	c = line[i];
	attr = c >> 16;
	c &= 0xffff;
	/* test for http link */
	if (c == 0x68 && (w - i) >= 8 && http_link_len == 0) {
	/* test http:// or https:// */
	if ((line[i + 1] & 0xffff) == 0x74 &&
	(line[i + 2] & 0xffff) == 0x74 &&
	(line[i + 3] & 0xffff) == 0x70 &&
	(((line[i + 4] & 0xffff) == 0x3a &&
	(line[i + 5] & 0xffff) == 0x2f &&
	(line[i + 6] & 0xffff) == 0x2f) \|\|
	((line[i + 4] & 0xffff) == 0x73 &&
	(line[i + 5] & 0xffff) == 0x3a &&
	(line[i + 6] & 0xffff) == 0x2f &&
	(line[i + 7] & 0xffff) == 0x2f))) {
	http_link_str = "";
	j = 0;
	while ((i + j) < w &&
	is_http_link_char(line[i + j] & 0xffff)) {
	http_link_str += String.fromCharCode(line[i + j] & 0xffff);
	j++;
	}
	http_link_len = j;
	if (last_attr != this.def_attr) {
	outline += '</span>';
	last_attr = this.def_attr;
	}
	outline += "<a href='" + http_link_str + "'>";
	}
	}
	if (i == cx) {
	attr = -1; /* cursor */
	}
	if (attr != last_attr) {
	if (last_attr != this.def_attr)
	outline += '</span>';
	if (attr != this.def_attr) {
	if (attr == -1) {
	/* cursor */
	outline += '<span class="term_cursor">';
	} else {
	outline += '<span style="';
	fg = (attr >> 3) & 7;
	bg = attr & 7;
	if (fg != 7) {
	outline += 'color:' + this.fg_colors[fg] + ';';
	}
	if (bg != 0) {
	outline += 'background-color:' +
	this.bg_colors[bg] + ';';
	}
	outline += '">';
	}
	}
	}
	switch(c) {
	case 32:
	outline += " ";
	break;
	case 38: // '&'
	outline += "&";
	break;
	case 60: // '<'
	outline += "<";
	break;
	case 62: // '>'
	outline += ">";
	break;
	default:
	if (c < 32) {
	outline += " ";
	} else {
	outline += String.fromCharCode(c);
	}
	break;
	}
	last_attr = attr;
	if (http_link_len != 0) {
	http_link_len--;
	if (http_link_len == 0) {
	if (last_attr != this.def_attr) {
	outline += '</span>';
	last_attr = this.def_attr;
	}
	outline += "</a>";
	}
	}
	}
	if (last_attr != this.def_attr) {
	outline += '</span>';
	}

	/* trim trailing spaces for copy/paste */
	outline = right_trim(outline, " ");
	if (outline == "")
	outline = " ";

	this.rows_el[y].innerHTML = outline;
	}

	this.refresh_scrollbar();
	};

	Term.prototype.cursor_timer_cb = function()
	{
	this.cursor_state ^= 1;
	this.refresh(this.y, this.y);
	};

	Term.prototype.show_cursor = function()
	{
	if (!this.cursor_state) {
	this.cursor_state = 1;
	this.refresh(this.y, this.y);
	}
	};

	Term.prototype.scroll = function()
	{
	var y, line, x, c, y1;

	/* increase height of buffer if possible */
	if (this.cur_h < this.tot_h) {
	this.cur_h++;
	}
	/* move down one line */
	if (++this.y_base == this.cur_h)
	this.y_base = 0;
	this.y_disp = this.y_base;

	c = 32 \| (this.def_attr << 16);
	line = new Array();
	for(x=0;x<this.w;x++)
	line[x] = c;
	y1 = this.y_base + this.h - 1;
	if (y1 >= this.cur_h)
	y1 -= this.cur_h;
	this.lines[y1] = line;
	};

	/* scroll down or up in the scroll back buffer by n lines */
	Term.prototype.scroll_disp = function(n)
	{
	var i, y1;
	/* slow but it does not really matters */
	if (n >= 0) {
	for(i = 0; i < n; i++) {
	if (this.y_disp == this.y_base)
	break;
	if (++this.y_disp == this.cur_h)
	this.y_disp = 0;
	}
	} else {
	n = -n;
	y1 = this.y_base + this.h;
	if (y1 >= this.cur_h)
	y1 -= this.cur_h;
	for(i = 0; i < n; i++) {
	if (this.y_disp == y1)
	break;
	if (--this.y_disp < 0)
	this.y_disp = this.cur_h - 1;
	}
	}
	this.refresh(0, this.h - 1);
	};

	Term.prototype.write = function(str)
	{
	function update(y)
	{
	ymin = Math.min(ymin, y);
	ymax = Math.max(ymax, y);
	}

	function erase_to_eol(s, x, y)
	{
	var l, i, c, y1;
	y1 = s.y_base + y;
	if (y1 >= s.cur_h)
	y1 -= s.cur_h;
	l = s.lines[y1];
	c = 32 \| (s.def_attr << 16);
	for(i = x; i < s.w; i++)
	l[i] = c;
	update(y);
	}

	function csi_colors(s, esc_params)
	{
	var j, n, fg, bg;

	if (esc_params.length == 0) {
	s.cur_attr= s.def_attr;
	} else {
	for(j = 0; j < esc_params.length; j++) {
	n = esc_params[j];
	if (n >= 30 && n <= 37) {
	/* foreground */
	fg = n - 30;
	s.cur_attr = (s.cur_attr & ~(7 << 3)) \| (fg << 3);
	} else if (n >= 40 && n <= 47) {
	/* background */
	bg = n - 40;
	s.cur_attr = (s.cur_attr & ~7) \| bg;
	} else if (n >= 90 && n <= 97) {
	/* foreground (XXX: 16 color table) */
	fg = n - 90;
	s.cur_attr = (s.cur_attr & ~(7 << 3)) \| (fg << 3);
	} else if (n >= 100 && n <= 107) {
	/* background (XXX: 16 color table) */
	bg = n - 100;
	s.cur_attr = (s.cur_attr & ~7) \| bg;
	} else if (n == 0) {
	/* default attr */
	s.cur_attr = s.def_attr;
	}
	}
	}
	}

	var TTY_STATE_NORM = 0;
	var TTY_STATE_ESC = 1;
	var TTY_STATE_CSI = 2;
	var TTY_STATE_CHARSET = 3;

	var i, c, ymin, ymax, l, n, j, y1;

	/* update region is in ymin ymax */
	ymin = this.h;
	ymax = -1;
	update(this.y); // remove the cursor
	/* reset top of displayed screen to top of real screen */
	if (this.y_base != this.y_disp) {
	this.y_disp = this.y_base;
	/* force redraw */
	ymin = 0;
	ymax = this.h - 1;
	}
	for(i = 0; i < str.length; i++) {
	c = str.charCodeAt(i);
	switch(this.state) {
	case TTY_STATE_NORM:
	switch(c) {
	case 10:
	this.y++;
	if (this.y >= this.h) {
	this.y--;
	this.scroll();
	ymin = 0;
	ymax = this.h - 1;
	}
	break;
	case 13:
	this.x = 0;
	break;
	case 8:
	if (this.x > 0) {
	this.x--;
	}
	break;
	case 9: /* tab */
	n = (this.x + 8) & ~7;
	if (n <= this.w) {
	this.x = n;
	}
	break;
	case 27:
	this.state = TTY_STATE_ESC;
	break;
	default:
	if (c >= 32) {
	if (this.x >= this.w) {
	this.x = 0;
	this.y++;
	if (this.y >= this.h) {
	this.y--;
	this.scroll();
	ymin = 0;
	ymax = this.h - 1;
	}
	}
	y1 = this.y + this.y_base;
	if (y1 >= this.cur_h)
	y1 -= this.cur_h;
	this.lines[y1][this.x] = (c & 0xffff) \|
	(this.cur_attr << 16);
	this.x++;
	update(this.y);
	}
	break;
	}
	break;
	case TTY_STATE_ESC:
	switch(c) {
	case 91: // '['
	this.esc_params = new Array();
	this.cur_param = 0;
	this.state = TTY_STATE_CSI;
	break;
	case 40: // '('
	case 41: // ')'
	this.state = TTY_STATE_CHARSET;
	break;
	default:
	this.state = TTY_STATE_NORM;
	break;
	}
	break;
	case TTY_STATE_CSI:
	if (c >= 48 && c <= 57) { // '0' '9'
	/* numeric */
	this.cur_param = this.cur_param * 10 + c - 48;
	} else {
	if (c == 63) // '?'
	break; /* ignore prefix */
	/* add parsed parameter */
	this.esc_params[this.esc_params.length] = this.cur_param;
	this.cur_param = 0;
	if (c == 59) // ;
	break;
	this.state = TTY_STATE_NORM;

	// console.log("term: csi=" + this.esc_params + " cmd="+c);
	switch(c) {
	case 65: // 'A' up
	n = this.esc_params[0];
	if (n < 1)
	n = 1;
	this.y -= n;
	if (this.y < 0)
	this.y = 0;
	break;
	case 66: // 'B' down
	n = this.esc_params[0];
	if (n < 1)
	n = 1;
	this.y += n;
	if (this.y >= this.h)
	this.y = this.h - 1;
	break;
	case 67: // 'C' right
	n = this.esc_params[0];
	if (n < 1)
	n = 1;
	this.x += n;
	if (this.x >= this.w - 1)
	this.x = this.w - 1;
	break;
	case 68: // 'D' left
	n = this.esc_params[0];
	if (n < 1)
	n = 1;
	this.x -= n;
	if (this.x < 0)
	this.x = 0;
	break;

	case 72: // 'H' goto xy
	{
	var x1, y1;
	y1 = this.esc_params[0] - 1;
	if (this.esc_params.length >= 2)
	x1 = this.esc_params[1] - 1;
	else
	x1 = 0;
	if (y1 < 0)
	y1 = 0;
	else if (y1 >= this.h)
	y1 = this.h - 1;
	if (x1 < 0)
	x1 = 0;
	else if (x1 >= this.w)
	x1 = this.w - 1;
	this.x = x1;
	this.y = y1;
	}
	break;
	case 74: // 'J' erase to end of screen
	erase_to_eol(this, this.x, this.y);
	for(j = this.y + 1; j < this.h; j++)
	erase_to_eol(this, 0, j);
	break;
	case 75: // 'K' erase to end of line
	erase_to_eol(this, this.x, this.y);
	break;
	case 109: // 'm': set color
	csi_colors(this, this.esc_params);
	break;
	case 110: // 'n' return the cursor position
	this.queue_chars("\x1b[" + (this.y + 1) + ";" + (this.x + 1) + "R");
	break;
	default:
	break;
	}
	}
	break;
	case TTY_STATE_CHARSET:
	/* just ignore */
	this.state = TTY_STATE_NORM;
	break;
	}
	}
	update(this.y); // show the cursor

	if (ymax >= ymin)
	this.refresh(ymin, ymax);
	};

	Term.prototype.writeln = function (str)
	{
	this.write(str + '\r\n');
	};

	Term.prototype.keyDownHandler = function (ev)
	{
	var str;

	str="";
	switch(ev.keyCode) {
	case 8: /* backspace */
	str = "\x7f";
	break;
	case 9: /* tab */
	str = "\x09";
	break;
	case 13: /* enter */
	str = "\x0d";
	break;
	case 27: /* escape */
	str = "\x1b";
	break;
	case 37: /* left */
	str = "\x1b[D";
	break;
	case 39: /* right */
	str = "\x1b[C";
	break;
	case 38: /* up */
	if (ev.ctrlKey) {
	this.scroll_disp(-1);
	} else {
	str = "\x1b[A";
	}
	break;
	case 40: /* down */
	if (ev.ctrlKey) {
	this.scroll_disp(1);
	} else {
	str = "\x1b[B";
	}
	break;
	case 46: /* delete */
	str = "\x1b[3~";
	break;
	case 45: /* insert */
	str = "\x1b[2~";
	break;
	case 36: /* home */
	str = "\x1bOH";
	break;
	case 35: /* end */
	str = "\x1bOF";
	break;
	case 33: /* page up */
	if (ev.ctrlKey) {
	this.scroll_disp(-(this.h - 1));
	} else {
	str = "\x1b[5~";
	}
	break;
	case 34: /* page down */
	if (ev.ctrlKey) {
	this.scroll_disp(this.h - 1);
	} else {
	str = "\x1b[6~";
	}
	break;
	default:
	if (ev.ctrlKey) {
	/* ctrl + key */
	if (ev.keyCode >= 65 && ev.keyCode <= 90) {
	str = String.fromCharCode(ev.keyCode - 64);
	} else if (ev.keyCode == 32) {
	str = String.fromCharCode(0);
	}
	} else if ((!this.is_mac && ev.altKey) \|\|
	(this.is_mac && ev.metaKey)) {
	/* meta + key (Note: we only send lower case) */
	if (ev.keyCode >= 65 && ev.keyCode <= 90) {
	str = "\x1b" + String.fromCharCode(ev.keyCode + 32);
	}
	}
	break;
	}
	// console.log("keydown: keycode=" + ev.keyCode + " charcode=" + ev.charCode + " str=" + str + " ctrl=" + ev.ctrlKey + " alt=" + ev.altKey + " meta=" + ev.metaKey);
	if (str) {
	if (ev.stopPropagation)
	ev.stopPropagation();
	if (ev.preventDefault)
	ev.preventDefault();

	this.show_cursor();
	this.key_rep_state = 1;
	this.key_rep_str = str;
	this.handler(str);
	return false;
	} else {
	this.key_rep_state = 0;
	return true;
	}
	};

	Term.prototype.keyPressHandler = function (ev)
	{
	var str, char_code;

	if (ev.stopPropagation)
	ev.stopPropagation();
	if (ev.preventDefault)
	ev.preventDefault();

	str="";
	if (!("charCode" in ev)) {
	/* on Opera charCode is not defined and keypress is sent for
	system keys. Moreover, only keupress is repeated which is a
	problem for system keys. */
	char_code = ev.keyCode;
	if (this.key_rep_state == 1) {
	this.key_rep_state = 2;
	return false;
	} else if (this.key_rep_state == 2) {
	/* repetition */
	this.show_cursor();
	this.handler(this.key_rep_str);
	return false;
	}
	} else {
	char_code = ev.charCode;
	}
	if (char_code != 0) {
	if (!ev.ctrlKey &&
	((!this.is_mac && !ev.altKey) \|\|
	(this.is_mac && !ev.metaKey))) {
	str = String.fromCharCode(char_code);
	}
	}
	// console.log("keypress: keycode=" + ev.keyCode + " charcode=" + ev.charCode + " str=" + str + " ctrl=" + ev.ctrlKey + " alt=" + ev.altKey + " meta=" + ev.metaKey);
	if (str) {
	this.show_cursor();
	this.handler(str);
	return false;
	} else {
	return true;
	}
	};

	Term.prototype.wheelHandler = function (ev)
	{
	if (ev.deltaY < 0)
	this.scroll_disp(-3);
	else if (ev.deltaY > 0)
	this.scroll_disp(3);
	ev.stopPropagation();
	}

	Term.prototype.mouseDownHandler = function (ev)
	{
	this.thumb_el.onmouseup = this.mouseUpHandler.bind(this);
	document.onmousemove = this.mouseMoveHandler.bind(this);
	document.onmouseup = this.mouseUpHandler.bind(this);

	/* disable potential selection */
	document.body.className += " noSelect";

	this.mouseMoveHandler(ev);
	}

	Term.prototype.mouseMoveHandler = function (ev)
	{
	var total_size, pos, new_y_disp, y, y0;
	total_size = this.term_el.clientHeight;
	y = ev.clientY - this.track_el.getBoundingClientRect().top;
	pos = Math.floor((y - (this.thumb_size / 2)) * this.cur_h / total_size);
	new_y_disp = Math.min(Math.max(pos, 0), this.cur_h - this.h);
	/* position of the first line of the scroll back buffer */
	y0 = (this.y_base + this.h) % this.cur_h;
	new_y_disp += y0;
	if (new_y_disp >= this.cur_h)
	new_y_disp -= this.cur_h;
	if (new_y_disp != this.y_disp) {
	this.y_disp = new_y_disp;
	this.refresh(0, this.h - 1);
	}
	}

	Term.prototype.mouseUpHandler = function (ev)
	{
	this.thumb_el.onmouseup = null;
	document.onmouseup = null;
	document.onmousemove = null;
	document.body.className = document.body.className.replace(" noSelect", "");
	}

	Term.prototype.pasteHandler = function (ev)
	{
	var c = ev.clipboardData;
	if (c) {
	this.queue_chars(c.getData("text/plain"));
	setTimeout(this.textAreaReset.bind(this), 10);
	return false;
	}
	}

	Term.prototype.textAreaReset = function(ev)
	{
	/* reset text */
	this.textarea_el.value = "Paste Here";
	}

	/* output queue to send back asynchronous responses */
	Term.prototype.queue_chars = function (str)
	{
	this.output_queue += str;
	if (this.output_queue)
	setTimeout(this.outputHandler.bind(this), 0);
	};

	Term.prototype.outputHandler = function ()
	{
	if (this.output_queue) {
	this.handler(this.output_queue);
	this.output_queue = "";
	}
	};

	Term.prototype.getSize = function ()
	{
	return [this.w, this.h];
	};