--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/webtty.js	Sun May 06 08:45:40 2012 -0700
@@ -0,0 +1,329 @@
+#!/usr/bin/env node
+var http = require('http');
+var url = require('url');
+var path = require('path');
+var fs = require('fs');
+//var tty = require("tty");
+var child_process = require("child_process");
+
+var serveStaticRoot = "/home/elwin/hk/nodejs/rlg/s/";
+var sessions = {};
+
+/* Constructor for TermSessions.  Note that it opens the terminal and 
+ * adds itself to the sessions dict. 
+ */
+function TermSession(sessid) {
+  //var pterm = tty.open("/bin/bash");
+  this.child = child_process.spawn("./ptywreck/ptyhelperC", ["bash"]);
+  var ss = this;
+  /* Eventually we'll need to make sure the sessid isn't in use yet. */
+  this.sessid = sessid;
+  //this.ptmx = pterm[0];
+  //this.child = pterm[1];
+  this.alive = true;
+  this.data = [];
+  this.child.stdout.on("data", function (buf) {
+    ss.data.push(buf);
+  });
+  this.child.stderr.on("data", function (buf) {
+    ss.data.push(buf);
+  });
+  this.child.on("exit", function (code, signal) {
+    ss.exitcode = (code != null ? code : 255);
+    ss.alive = false;
+    /* Wait for all the data to get collected */
+    setTimeout(ss.cleanup, 1000);
+  });
+  this.write = function (data) {
+    if (this.alive)
+      this.child.stdin.write(data);
+    /* Otherwise, throw some kind of exception? */
+  };
+  this.read = function () {
+    if (this.data.length == 0)
+      return null;
+    var pos = 0;
+    var i = 0;
+    for (i = 0; i < this.data.length; i++)
+      pos += this.data[i].length;
+    var nbuf = new Buffer(pos);
+    var tptr;
+    pos = 0;
+    while (this.data.length > 0) {
+      tptr = this.data.shift();
+      tptr.copy(nbuf, pos);
+      pos += tptr.length;
+    }
+    return nbuf;
+  };
+  this.close = function () {
+    if (this.alive)
+      this.child.kill('SIGHUP');
+  };
+  this.cleanup = function () {
+    /* Call this when the child is dead. */
+    if (this.alive)
+      return;
+    //ss.ptmx.destroy();
+    /* Give the client a chance to read any leftover data. */
+    if (ss.data.length > 0)
+      setTimeout(ss.remove, 8000);
+    else
+      ss.remove();
+  };
+  this.remove = function () {
+    delete sessions[ss.sessid];
+    console.log("Session " + this.sessid + " removed.");
+  };
+  sessions[sessid] = this;
+}
+
+function randkey() {
+  rnum = Math.floor(Math.random() * 65536 * 65536);
+  hexstr = rnum.toString(16);
+  while (hexstr.length < 8)
+    hexstr = "0" + hexstr;
+  return hexstr;
+}
+
+/* Returns a list of the cookies in the request, obviously. */
+function getCookies(req) {
+  cookies = [];
+  if ("cookie" in req.headers) {
+    cookstrs = req.headers["cookie"].split("; ");
+    for (var i = 0; i < cookstrs.length; i++) {
+      eqsign = cookstrs[i].indexOf("=");
+      if (eqsign > 0) {
+        name = cookstrs[i].slice(0, eqsign).toLowerCase();
+        val = cookstrs[i].slice(eqsign + 1);
+        cookies[name] = val;
+      }
+      else if (eqsign < 0)
+        cookies[cookstrs[i]] = null;
+    }
+  }
+  return cookies;
+}
+
+function urlDec(encstr) {
+  var decstr = "";
+  var tnum;
+  for (var i = 0; i < encstr.length; i++)
+  {
+    if (encstr.charAt(i) == "+")
+      decstr += " ";
+    else if (encstr.charAt(i) == "%")
+    {
+      tnum = Number("0x" + encstr.slice(i + 1, 2));
+      if (!isNaN(tnum) && tnum >= 0)
+        decstr += String.fromCharCode(tnum);
+      i += 2;
+    }
+    else
+      decstr += encstr.charAt(i);
+  }
+  return decstr;
+}
+
+/* Returns the contents of a form */
+function getFormValues(formtext) {
+  var pairstrs = formtext.split("&");
+  var data = {};
+  for (var i = 0; i < pairstrs.length; i++)
+  {
+    var eqsign = pairstrs[i].indexOf("=");
+    if (eqsign > 0) {
+      rawname = pairstrs[i].slice(0, eqsign);
+      rawval = pairstrs[i].slice(eqsign + 1);
+      name = urlDec(rawname);
+      val = urlDec(rawval);
+      if (!(name in data))
+        data[name] = [];
+      data[name].push(val);
+    }
+  }
+  return data;
+}
+
+function login(req, res, formdata) {
+  var resheaders = {'Content-Type': 'text/plain'};
+  var sessid = randkey();
+  var nsession = new TermSession(sessid);
+  resheaders["Set-Cookie"] = "ID=" + sessid;
+  res.writeHead(200, resheaders);
+  res.write("l1\n" + sessid + "\n");
+  res.end();
+  console.log("Started new session with key " + sessid + ", pid " + nsession.child.pid);
+  return;
+}
+
+function findTermSession(req) {
+  var cookies = getCookies(req);
+  if ("id" in cookies) {
+    var sessid = cookies["id"];
+    if (sessid in sessions) {
+      return sessions[sessid];
+    }
+  }
+  return null;
+}
+
+function serveStatic(req, res, fname) {
+  var nname = path.normalize(fname);
+  if (nname == "" || nname == "/")
+    nname = "index.html";
+  if (nname.match(/\/$/))
+    path.join(nname, "index.html"); /* it was a directory */
+  var realname = path.join(serveStaticRoot, nname);
+  var extension = path.extname(realname);
+  path.exists(realname, function (exists) {
+    var resheaders = {};
+    if (!exists || !extension || extension == ".html")
+      resheaders["Content-Type"] = "text/html";
+    else if (extension == ".png")
+      resheaders["Content-Type"] = "image/png";
+    else if (extension == ".css")
+      resheaders["Content-Type"] = "text/css";
+    else if (extension == ".js")
+      resheaders["Content-Type"] = "text/javascript";
+    else if (extension == ".svg")
+      resheaders["Content-Type"] = "image/svg+xml";
+    else
+      resheaders["Content-Type"] = "application/octet-stream";
+    if (exists) {
+      /* Not nice, not sensible.  First see if it's readable, then respond
+       * 200 or 500.  Don't throw nasty errors. */
+      res.writeHead(200, resheaders);
+      fs.readFile(realname, function (error, data) {
+        if (error) throw error;
+        res.write(data);
+        res.end();
+      });
+    }
+    else {
+      res.writeHead(404, resheaders);
+      res.write("<html><head><title>" + nname + "</title></head>\n<body><h1>" + nname + " Not Found</h1></body></html>\n");
+      res.end();
+    }
+  });
+  return;
+}
+
+function readFeed(res, term) {
+  res.writeHead(200, { "Content-Type": "text/plain" });
+  if (term) {
+    var result = term.read();
+    if (result == null)
+      resultstr = "";
+    else
+      resultstr = result.toString("hex");
+    res.write("d" + resultstr.length.toString() + "\n" + resultstr + "\n");
+  }
+  else {
+    //console.log("Where's the term?");
+    res.write("d0\n\n");
+  }
+}
+
+var errorcodes = [ "Generic Error", "Not logged in", "Invalid data" ];
+
+function sendError(res, ecode) {
+  res.writeHead(200, { "Content-Type": "text/plain" });
+  if (ecode < errorcodes.length && ecode > 0)
+    res.write("E" + ecode + '\n' + errorcodes[ecode] + '\n');
+  else
+    res.write("E0\nGeneric Error\n");
+  res.end();
+}
+
+function handler(req, res) {
+  /* default headers for the response */
+  var resheaders = {'Content-Type': 'text/html'};
+  /* The request body will be added to this as it arrives. */
+  var reqbody = "";
+  var formdata;
+
+  /* Register a listener to get the body. */
+  function moredata(chunk) {
+    reqbody += chunk;
+  }
+  req.on('data', moredata);
+
+  /* This will send the response once the whole request is here. */
+  function respond() {
+    var target = url.parse(req.url).pathname;
+    var cterm = findTermSession(req);
+    /* First figure out if the client is POSTing to a command interface. */
+    if (req.method == 'POST') {
+      formdata = getFormValues(reqbody);
+      if (target == '/feed') {
+        if (!cterm) {
+          sendError(res, 1);
+          return;
+        }
+        if (formdata["quit"] == "quit") {
+          /* The client wants to quit. */
+          // FIXME need to send a message back to the client
+          cterm.close();
+        }
+        else if (formdata["keys"]) {
+          /* process the keys */
+          hexstr = formdata["keys"][0].replace(/[^0-9a-f]/gi, "");
+          if (hexstr.length % 2 != 0) {
+            sendError(res, 2);
+            return;
+          }
+          keybuf = new Buffer(hexstr, "hex");
+          cterm.write(keybuf);
+        }
+        readFeed(res, cterm);
+        res.end();
+      }
+      else if (target == "/login") {
+        login(req, res, formdata);
+      }
+      else {
+        res.writeHead(405, resheaders);
+        res.end();
+      }
+    }
+    else if (req.method == 'GET' || req.method == 'HEAD') {
+      if (target == '/feed') {
+        if (!cterm) {
+          sendError(res, 1);
+          return;
+        }
+        readFeed(res, cterm);
+        res.end();
+      }
+      /* Default page, create a new term */
+      /* FIXME New term not created anymore, is a special case still needed? */
+      else if (target == '/') {
+        serveStatic(req, res, "/");
+      }
+      else /* Go look for it in the filesystem */
+        serveStatic(req, res, target);
+    }
+    else { /* Some other method */
+      res.writeHead(501, resheaders);
+      res.write("<html><head><title>501</title></head>\n<body><h1>501 Not Implemented</h1></body></html>\n");
+      res.end();
+    }
+    return;
+  }
+  req.on('end', respond);
+
+}
+
+process.on("exit", function () {
+  for (var sessid in sessions) {
+    if (sessions[sessid].alive)
+      sessions[sessid].child.kill('SIGHUP');
+  }
+  console.log("Quitting...");
+  return;
+});
+
+process.env["TERM"] = "xterm-256color";
+http.createServer(handler).listen(8080, "127.0.0.1");
+console.log('Server running at http://127.0.0.1:8080/');