Add beginning of build-in debugger

+ test-debugger-client (which is currently broken)

lib/_debugger.js

@@ -0,0 +1,221 @@
+var net = require('net');
+var readline = require('readline');
+var inherits = require('util').inherits;
+
+exports.port = 5858;
+
+exports.start = function (pid) {
+  if (pid) {
+    process.kill(pid, "SIGUSR1");
+    setTimeout(tryConnect, 100);
+  } else {
+    tryConnect();
+  }
+};
+
+var c;
+
+function tryConnect() {
+  c = new Client();
+
+  process.stdout.write("connecting...");
+  c.connect(exports.port, function () {
+    process.stdout.write("ok\r\n");
+    startInterface();
+  });
+
+}
+
+//
+// Parser/Serializer for V8 debugger protocol
+// http://code.google.com/p/v8/wiki/DebuggerProtocol
+//
+// Usage:
+//    p = new Protocol();
+//
+//    p.onResponse = function (res) {
+//      // do stuff with response from V8
+//    };
+//
+//    socket.setEncoding('utf8');
+//    socket.on('data', function (s) {
+//      // Pass strings into the protocol
+//      p.execute(s);
+//    });
+//
+//
+function Protocol() {
+  this._newRes();
+}
+exports.Protocol = Protocol;
+
+
+Protocol.prototype._newRes = function(raw) {
+  this.res = { raw: raw || '', headers: {} };
+  this.state = 'headers';
+  this.reqSeq = 1;
+};
+
+
+Protocol.prototype.execute = function(d) {
+  var res = this.res;
+  res.raw += d;
+
+  switch (this.state) {
+    case 'headers':
+      var endHeaderIndex = res.raw.indexOf('\r\n\r\n');
+
+      if (endHeaderIndex < 0) break;
+
+      var lines = res.raw.slice(0, endHeaderIndex).split('\r\n');
+      for (var i = 0; i < lines.length; i++) {
+        var kv = lines[i].split(/: +/);
+        res.headers[kv[0]] = kv[1];
+      }
+
+      this.contentLength = +res.headers['Content-Length'];
+      this.bodyStartIndex = endHeaderIndex + 4;
+
+      this.state = 'body';
+      if (res.raw.length - this.bodyStartIndex < this.contentLength) break;
+      // pass thru
+
+    case 'body':
+      if (res.raw.length - this.bodyStartIndex >= this.contentLength) {
+        res.body =
+            res.raw.slice(this.bodyStartIndex,
+                          this.bodyStartIndex + this.contentLength);
+        // JSON parse body?
+        res.body = res.body.length ? JSON.parse(res.body) : {};
+
+        // Done!
+        this.onResponse(res);
+
+        this._newRes(res.raw.slice(this.bodyStartIndex + this.contentLength));
+      }
+      break;
+
+    default:
+      throw new Error("Unknown state");
+      break;
+  }
+};
+
+
+Protocol.prototype.serialize = function(req) {
+  req.type = 'request';
+  req.seq = this.reqSeq++;
+  var json = JSON.stringify(req);
+  return 'Content-Length: ' + json.length + '\r\n\r\n' + json;
+};
+
+
+
+
+function Client() {
+  net.Stream.call(this);
+  var protocol = this.protocol = new Protocol(c);
+  this._reqCallbacks = [];
+  var socket = this;
+
+  // Note that 'Protocol' requires strings instead of Buffers.
+  socket.setEncoding('utf8');
+  socket.on('data', function(d) {
+    protocol.execute(d);
+  });
+
+  protocol.onResponse = this._onResponse.bind(this);
+};
+inherits(Client, net.Stream);
+exports.Client = Client;
+
+
+Client.prototype._onResponse = function(res) {
+  console.error(res);
+  for (var i = 0; i < this._reqCallbacks.length; i++) {
+    var cb = this._reqCallbacks[i];
+    if (this._reqCallbacks[i].request_seq == cb.request_seq) break;
+  }
+
+  if (cb) {
+    this._reqCallbacks.splice(i, 1);
+    cb(res.body);
+  } else if (res.headers.Type == 'connect') {
+    // do nothing
+  } else {
+    console.error("unhandled res: %j", res.body);
+  }
+};
+
+
+Client.prototype.req = function(req, cb) {
+  this.write(this.protocol.serialize(req));
+  cb.request_seq = req.seq;
+  this._reqCallbacks.push(cb);
+};
+
+
+Client.prototype.reqVersion = function(cb) {
+  this.req({ command: 'version' } , function (res) {
+    if (cb) cb(res.body.V8Version, res.running);
+  });
+};
+
+
+var helpMessage = "Commands: version, eval, help, quit";
+
+
+function startInterface() {
+
+  var i = readline.createInterface(process.stdout);
+  var stdin = process.openStdin();
+  stdin.addListener('data', function(chunk) {
+    i.write(chunk);
+  });
+
+  var prompt = '> ';
+
+  i.setPrompt(prompt);
+  i.prompt();
+
+  i.on('SIGINT', function() {
+    i.close();
+  });
+
+  i.on('line', function(cmd) {
+    if (cmd == 'quit') {
+      process.exit(0);
+    } else if (/^help/.test(cmd)) {
+      console.log(helpMessage);
+      i.prompt();
+
+    } else if ('version' == cmd) {
+      c.reqVersion(function (v) {
+        console.log(v);
+        i.prompt();
+      });
+
+    } else if (/^eval/.test(cmd)) {
+      var req = {
+        command: 'evaluate',
+        arguments: { 'expression': cmd.slice(5) }
+      };
+
+      c.req(req, function (res) {
+        console.log(res);
+        i.prompt();
+      });
+
+    } else {
+      if (!/^\s*$/.test(cmd)) {
+        // If it's not all white-space print this error message.
+        console.log('Unknown command "%s". Try "help"', cmd);
+      }
+      i.prompt();
+    }
+  });
+
+  i.on('close', function() {
+    stdin.destroy();
+  });
+}

src/node.js

@@ -535,14 +535,23 @@
   }
 
   if (process.argv[1]) {
-    // Load module
-    if (process.argv[1].charAt(0) != '/' &&
-        !(/^http:\/\//).exec(process.argv[1])) {
-      process.argv[1] = path.join(cwd, process.argv[1]);
+
+    if (process.argv[1] == 'debug') {
+      // Start the debugger agent
+      var d = requireNative('_debugger');
+      var pid = process.argv[2];
+      d.start(pid);
+
+    } else {
+      // Load module
+      if (process.argv[1].charAt(0) != '/' &&
+          !(/^http:\/\//).exec(process.argv[1])) {
+        process.argv[1] = path.join(cwd, process.argv[1]);
+      }
+      // REMOVEME: nextTick should not be necessary. This hack to get
+      // test/simple/test-exception-handler2.js working.
+      process.nextTick(module.runMain);
     }
-    // REMOVEME: nextTick should not be necessary. This hack to get
-    // test/simple/test-exception-handler2.js working.
-    process.nextTick(module.runMain);
 
   } else if (process._eval) {
     // -e, --eval

test/simple/test-debugger-client.js

@@ -0,0 +1,63 @@
+var common = require('../common');
+var assert = require('assert');
+var d = require('_debugger');
+
+var spawn = require('child_process').spawn;
+
+
+var resCount = 0;
+var p = new d.Protocol();
+p.onResponse = function (res) {
+  resCount++;
+};
+
+p.execute("Type: connect\r\n" +
+          "V8-Version: 3.0.4.1\r\n" +
+          "Protocol-Version: 1\r\n" +
+          "Embedding-Host: node v0.3.3-pre\r\n" +
+          "Content-Length: 0\r\n\r\n");
+assert.equal(1, resCount);
+
+var n = spawn(process.execPath,
+              ['-e', 'setInterval(function () { console.log("blah"); }, 1000);']);
+
+
+var connected = false;
+
+n.stdout.once('data', function () {
+  console.log("new node process: %d", n.pid);
+  process.kill(n.pid, "SIGUSR1");
+  console.log("signaling it with SIGUSR1");
+
+});
+
+var didTryConnect = false;
+n.stderr.setEncoding('utf8');
+n.stderr.on('data', function (d) {
+  if (didTryConnect == false && /debugger/.test(d)) {
+    didTryConnect = true;
+    tryConnect();
+  }
+})
+
+
+function tryConnect() {
+  // Wait for some data before trying to connect
+  var c = new d.Client();
+  process.stdout.write("connecting...");
+  c.connect(d.port, function () {
+    connected = true;
+    console.log("connected!");
+  });
+
+  c.reqVersion(function (v) {
+    assert.equal(process.versions.v8, v);
+    n.kill();
+  });
+}
+
+
+process.on('exit', function() {
+  assert.ok(connected);
+});
+