net: refactor server.listen flow control

nodejs · Mar 5, 2017 · bcd4ff7 · bcd4ff7
1 parent ce3fc05
commit bcd4ff7
Showing 1 changed file with 40 additions and 36 deletions.
diff --git a/lib/net.js b/lib/net.js
@@ -24,7 +24,6 @@ var cluster;
 const errnoException = util._errnoException;
 const exceptionWithHostPort = util._exceptionWithHostPort;
 const isLegalPort = internalNet.isLegalPort;
-const assertPort = internalNet.assertPort;
 
 function noop() {}
 
@@ -1363,14 +1362,6 @@ Server.prototype.listen = function() {
   if (hasCallback) {
     this.once('listening', cb);
   }
-
-  // ([port][, host][, backlog][, cb]) where port is omitted,
-  // that is, listen() or listen(cb),
-  if (args.length === 0 || typeof args[0] === 'function') {
-    // Bind to a random port.
-    options.port = 0;
-  }
-
   const backlogFromArgs =
     // (handle, backlog) or (path, backlog) or (port, backlog)
     toNumber(args.length > 1 && args[1]) ||
@@ -1381,38 +1372,51 @@ Server.prototype.listen = function() {
   if (options instanceof TCP) {
     this._handle = options;
     listen(this, null, -1, -1, backlogFromArgs);
-  } else if (typeof options.fd === 'number' && options.fd >= 0) {
-    // (handle[, backlog][, cb]) where handle is an object with a fd
+    return this;
+  }
+  // (handle[, backlog][, cb]) where handle is an object with a fd
+  if (typeof options.fd === 'number' && options.fd >= 0) {
     listen(this, null, null, null, backlogFromArgs, options.fd);
-  } else {
-    const backlog = options.backlog || backlogFromArgs;
+    return this;
+  }
 
-    // ([port][, host][, backlog][, cb]) where port is specified
-    // or (options[, cb]) where options.port is specified
-    if (typeof options.port === 'number' || typeof options.port === 'string' ||
-        (typeof options.port === 'undefined' && 'port' in options)) {
-      // if (options[, cb]) where options.port is explicitly set as undefined,
-      // bind to an arbitrary unused port
-      assertPort(options.port);
-      // start TCP server listening on host:port
-      if (options.host) {
-        lookupAndListen(this, options.port | 0, options.host, backlog,
-                        options.exclusive);
-      } else { // Undefined host, listens on unspecified IPv4 address
-        listen(this, null, options.port | 0, 4, backlog, undefined,
-               options.exclusive);
-      }
-    } else if (options.path && isPipeName(options.path)) {
-      // (path[, backlog][, cb]) or (options[, cb])
-      // where path or options.path is a UNIX domain socket or Windows pipe
-      const pipeName = this._pipeName = options.path;
-      listen(this, pipeName, -1, -1, backlog, undefined, options.exclusive);
-    } else {
-      throw new Error('Invalid listen argument: ' + options);
+  // ([port][, host][, backlog][, cb]) where port is omitted,
+  // that is, listen() or listen(cb),
+  // or (options[, cb]) where options.port is explicitly set as undefined,
+  // bind to an arbitrary unused port
+  if (args.length === 0 || typeof args[0] === 'function' ||
+    (typeof options.port === 'undefined' && 'port' in options)) {
+    options.port = 0;
+  }
+  // ([port][, host][, backlog][, cb]) where port is specified
+  // or (options[, cb]) where options.port is specified
+  // or if options.port is normalized as 0 before
+  if (typeof options.port === 'number' || typeof options.port === 'string') {
+    if (!isLegalPort(options.port)) {
+      throw new RangeError('"port" argument must be >= 0 and < 65536');
+    }
+    const backlog = options.backlog || backlogFromArgs;
+    // start TCP server listening on host:port
+    if (options.host) {
+      lookupAndListen(this, options.port | 0, options.host, backlog,
+                      options.exclusive);
+    } else { // Undefined host, listens on unspecified address
+      listen(this, null, options.port | 0, 4, // addressType will be ignored
+             backlog, undefined, options.exclusive);
     }
+    return this;
   }
 
-  return this;
+  // (path[, backlog][, cb]) or (options[, cb])
+  // where path or options.path is a UNIX domain socket or Windows pipe
+  if (options.path && isPipeName(options.path)) {
+    const pipeName = this._pipeName = options.path;
+    const backlog = options.backlog || backlogFromArgs;
+    listen(this, pipeName, -1, -1, backlog, undefined, options.exclusive);
+    return this;
+  }
+
+  throw new Error('Invalid listen argument: ' + options);
 };
 
 function lookupAndListen(self, port, address, backlog, exclusive) {