net: report uv_tcp_open() errors

uv_tcp_open() can fail. Prior to this commit, any error was
being silently ignored. This commit raises the errors.
PR-URL: #21428
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: cjihrig

lib/net.js

@@ -260,8 +260,14 @@ function Socket(options) {
 this[async_id_symbol]=getNewAsyncId(this._handle);
 }elseif(options.fd!==undefined){
 const{ fd }=options;
+leterr;
+
 this._handle=createHandle(fd,false);
-this._handle.open(fd);
+
+err=this._handle.open(fd);
+if(err)
+throwerrnoException(err,'open');
+
 this[async_id_symbol]=this._handle.getAsyncId();
 // options.fd can be string (since it is user-defined),
 // so changing this to === would be semver-major
@@ -271,7 +277,7 @@ function Socket(options) {
 (this._handleinstanceofPipe)&&
 process.platform==='win32'){
 // Make stdout and stderr blocking on Windows
-varerr=this._handle.setBlocking(true);
+err=this._handle.setBlocking(true);
 if(err)
 throwerrnoException(err,'setBlocking');
 
@@ -1237,7 +1243,11 @@ function createServerHandle(address, port, addressType, fd) {
 debug('listen invalid fd=%d:',fd,e.message);
 returnUV_EINVAL;
 }
-handle.open(fd);
+
+err=handle.open(fd);
+if(err)
+returnerr;
+
 handle.readable=true;
 handle.writable=true;
 assert(!address&&!port);

src/tcp_wrap.cc

@@ -211,8 +211,12 @@ void TCPWrap::Open(const FunctionCallbackInfo<Value>& args) {
  args.Holder(),
  args.GetReturnValue().Set(UV_EBADF));
 int fd = static_cast<int>(args[0]->IntegerValue());
-uv_tcp_open(&wrap->handle_, fd);
- wrap->set_fd(fd);
+int err = uv_tcp_open(&wrap->handle_, fd);
+
+if (err == 0)
+ wrap->set_fd(fd);
+
+ args.GetReturnValue().Set(err);
 }