errors: move error creation helpers to errors.js

This commit moves error creation helpers scattered around under lib/ into lib/internal/errors.js in the hope of being clearer about the differences of errors that we throw into the user land. - Move util._errnoException and util._exceptionWithHostPort into internal/errors.js and simplify their logic so it's clearer what the properties these helpers create. - Move the errnoException helper in dns.js to internal/errors.js into internal/errors.js and rename it to dnsException. Simplify it's logic so it no longer calls errnoException and skips the unnecessary argument checks. Backport-PR-URL: #19191 PR-URL: #18546 Reviewed-By: James M Snell <[email protected]>

Author: joyeecheung

lib/dgram.js

@@ -45,8 +45,8 @@ const SEND_BUFFER = false;
 // Lazily loaded
 varcluster=null;
 
-consterrnoException=util._errnoException;
-constexceptionWithHostPort=util._exceptionWithHostPort;
+consterrnoException=errors.errnoException;
+constexceptionWithHostPort=errors.exceptionWithHostPort;
 
 
 functionlookup4(lookup,address,callback){

lib/dns.js

@@ -21,12 +21,10 @@
 
 'use strict';
 
-constutil=require('util');
-
 constcares=process.binding('cares_wrap');
-constuv=process.binding('uv');
 const{ isLegalPort }=require('internal/net');
 const{ customPromisifyArgs }=require('internal/util');
+consterrors=require('internal/errors');
 
 const{
  GetAddrInfoReqWrap,
@@ -36,30 +34,6 @@ const{
  isIP
 }=cares;
 
-functionerrnoException(err,syscall,hostname){
-// FIXME(bnoordhuis) Remove this backwards compatibility nonsense and pass
-// the true error to the user. ENOTFOUND is not even a proper POSIX error!
-if(err===uv.UV_EAI_MEMORY||
-err===uv.UV_EAI_NODATA||
-err===uv.UV_EAI_NONAME){
-err='ENOTFOUND';
-}
-varex=null;
-if(typeoferr==='string'){// c-ares error code.
-consterrHost=hostname ? ` ${hostname}` : '';
-ex=newError(`${syscall}${err}${errHost}`);
-ex.code=err;
-ex.errno=err;
-ex.syscall=syscall;
-}else{
-ex=util._errnoException(err,syscall);
-}
-if(hostname){
-ex.hostname=hostname;
-}
-returnex;
-}
-
 constIANA_DNS_PORT=53;
 constdigits=[
 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,// 0-15
@@ -86,10 +60,11 @@ function isIPv4(str){
 return(str.length>3&&str.charCodeAt(3)===46/*'.'*/);
 }
 
+constdnsException=errors.dnsException;
 
 functiononlookup(err,addresses){
 if(err){
-returnthis.callback(errnoException(err,'getaddrinfo',this.hostname));
+returnthis.callback(dnsException(err,'getaddrinfo',this.hostname));
 }
 if(this.family){
 this.callback(null,addresses[0],this.family);
@@ -101,7 +76,7 @@ function onlookup(err, addresses){
 
 functiononlookupall(err,addresses){
 if(err){
-returnthis.callback(errnoException(err,'getaddrinfo',this.hostname));
+returnthis.callback(dnsException(err,'getaddrinfo',this.hostname));
 }
 
 varfamily=this.family;
@@ -181,7 +156,7 @@ function lookup(hostname, options, callback){
 
 varerr=cares.getaddrinfo(req,hostname,family,hints,verbatim);
 if(err){
-process.nextTick(callback,errnoException(err,'getaddrinfo',hostname));
+process.nextTick(callback,dnsException(err,'getaddrinfo',hostname));
 return{};
 }
 returnreq;
@@ -193,7 +168,7 @@ Object.defineProperty(lookup, customPromisifyArgs,
 
 functiononlookupservice(err,host,service){
 if(err)
-returnthis.callback(errnoException(err,'getnameinfo',this.host));
+returnthis.callback(dnsException(err,'getnameinfo',this.host));
 
 this.callback(null,host,service);
 }
@@ -222,7 +197,7 @@ function lookupService(host, port, callback){
 req.oncomplete=onlookupservice;
 
 varerr=cares.getnameinfo(req,host,port);
-if(err)throwerrnoException(err,'getnameinfo',host);
+if(err)throwdnsException(err,'getnameinfo',host);
 returnreq;
 }
 
@@ -235,7 +210,7 @@ function onresolve(err, result, ttls){
 result=result.map((address,index)=>({ address,ttl: ttls[index]}));
 
 if(err)
-this.callback(errnoException(err,this.bindingName,this.hostname));
+this.callback(dnsException(err,this.bindingName,this.hostname));
 else
 this.callback(null,result);
 }
@@ -272,7 +247,7 @@ function resolver(bindingName){
 req.oncomplete=onresolve;
 req.ttl=!!(options&&options.ttl);
 varerr=this._handle[bindingName](req,name);
-if(err)throwerrnoException(err,bindingName);
+if(err)throwdnsException(err,bindingName);
 returnreq;
 }
 Object.defineProperty(query,'name',{value: bindingName});

lib/fs.js

@@ -59,7 +59,7 @@ const{kMaxLength } = require('buffer');
 constisWindows=process.platform==='win32';
 
 constDEBUG=process.env.NODE_DEBUG&&/fs/.test(process.env.NODE_DEBUG);
-consterrnoException=util._errnoException;
+consterrnoException=errors.errnoException;
 
 functiongetOptions(options,defaultOptions){
 if(options===null||options===undefined||

lib/internal/child_process.js

@@ -18,7 +18,7 @@ const SocketList = require('internal/socket_list');
 const{ convertToValidSignal }=require('internal/util');
 const{ isUint8Array }=require('internal/util/types');
 
-consterrnoException=util._errnoException;
+consterrnoException=errors.errnoException;
 const{ SocketListSend, SocketListReceive }=SocketList;
 
 constMAX_HANDLE_RETRANSMISSIONS=3;

lib/internal/errors.js

@@ -11,6 +11,11 @@
 constkCode=Symbol('code');
 constmessages=newMap();
 
+const{
+UV_EAI_MEMORY,
+UV_EAI_NODATA,
+UV_EAI_NONAME
+}=process.binding('uv');
 const{ defineProperty }=Object;
 
 // Lazily loaded
@@ -22,6 +27,14 @@ function lazyUtil(){
 returnutil_;
 }
 
+varinternalUtil=null;
+functionlazyInternalUtil(){
+if(!internalUtil){
+internalUtil=require('internal/util');
+}
+returninternalUtil;
+}
+
 functionmakeNodeError(Base){
 returnclassNodeErrorextendsBase{
 constructor(key, ...args){
@@ -125,7 +138,110 @@ function E(sym, val){
 messages.set(sym,typeofval==='function' ? val : String(val));
 }
 
+/**
+ * This used to be util._errnoException().
+ *
+ * @param{number} err - A libuv error number
+ * @param{string} syscall
+ * @param{string} [original]
+ * @returns{Error}
+ */
+functionerrnoException(err,syscall,original){
+// TODO(joyeecheung): We have to use the type-checked
+// getSystemErrorName(err) to guard against invalid arguments from users.
+// This can be replaced with [ code ] = errmap.get(err) when this method
+// is no longer exposed to user land.
+constcode=lazyUtil().getSystemErrorName(err);
+constmessage=original ?
+`${syscall}${code}${original}` : `${syscall}${code}`;
+
+constex=newError(message);
+// TODO(joyeecheung): errno is supposed to err, like in uvException
+ex.code=ex.errno=code;
+ex.syscall=syscall;
+
+Error.captureStackTrace(ex,errnoException);
+returnex;
+}
+
+/**
+ * This used to be util._exceptionWithHostPort().
+ *
+ * @param{number} err - A libuv error number
+ * @param{string} syscall
+ * @param{string} address
+ * @param{number} [port]
+ * @param{string} [additional]
+ * @returns{Error}
+ */
+functionexceptionWithHostPort(err,syscall,address,port,additional){
+// TODO(joyeecheung): We have to use the type-checked
+// getSystemErrorName(err) to guard against invalid arguments from users.
+// This can be replaced with [ code ] = errmap.get(err) when this method
+// is no longer exposed to user land.
+constcode=lazyUtil().getSystemErrorName(err);
+letdetails='';
+if(port&&port>0){
+details=` ${address}:${port}`;
+}elseif(address){
+details=` ${address}`;
+}
+if(additional){
+details+=` - Local (${additional})`;
+}
+
+constex=newError(`${syscall}${code}${details}`);
+// TODO(joyeecheung): errno is supposed to err, like in uvException
+ex.code=ex.errno=code;
+ex.syscall=syscall;
+ex.address=address;
+if(port){
+ex.port=port;
+}
+
+Error.captureStackTrace(ex,exceptionWithHostPort);
+returnex;
+}
+
+/**
+ * @param{number|string} err - A libuv error number or a c-ares error code
+ * @param{string} syscall
+ * @param{string} [hostname]
+ * @returns{Error}
+ */
+functiondnsException(err,syscall,hostname){
+constex=newError();
+// FIXME(bnoordhuis) Remove this backwards compatibility nonsense and pass
+// the true error to the user. ENOTFOUND is not even a proper POSIX error!
+if(err===UV_EAI_MEMORY||
+err===UV_EAI_NODATA||
+err===UV_EAI_NONAME){
+err='ENOTFOUND';// Fabricated error name.
+}
+if(typeoferr==='string'){// c-ares error code.
+consterrHost=hostname ? ` ${hostname}` : '';
+ex.message=`${syscall}${err}${errHost}`;
+// TODO(joyeecheung): errno is supposed to be a number, like in uvException
+ex.code=ex.errno=err;
+ex.syscall=syscall;
+}else{// libuv error number
+constcode=lazyInternalUtil().getSystemErrorName(err);
+ex.message=`${syscall}${code}`;
+// TODO(joyeecheung): errno is supposed to be err, like in uvException
+ex.code=ex.errno=code;
+ex.syscall=syscall;
+}
+if(hostname){
+ex.hostname=hostname;
+}
+Error.captureStackTrace(ex,dnsException);
+returnex;
+}
+
 module.exports=exports={
+ dnsException,
+ errnoException,
+ exceptionWithHostPort,
  message,
 Error: makeNodeError(Error),
 TypeError: makeNodeError(TypeError),

lib/internal/http2/core.js

@@ -1647,7 +1647,7 @@ class Http2Stream extends Duplex{
 req.async=false;
 consterr=createWriteReq(req,handle,data,encoding);
 if(err)
-returnthis.destroy(util._errnoException(err,'write',req.error),cb);
+returnthis.destroy(errors.errnoException(err,'write',req.error),cb);
 trackWriteState(this,req.bytes);
 }
 
@@ -1690,7 +1690,7 @@ class Http2Stream extends Duplex{
 }
 consterr=handle.writev(req,chunks);
 if(err)
-returnthis.destroy(util._errnoException(err,'write',req.error),cb);
+returnthis.destroy(errors.errnoException(err,'write',req.error),cb);
 trackWriteState(this,req.bytes);
 }
 

lib/internal/process.js

@@ -1,5 +1,6 @@
 'use strict';
 
+consterrors=require('internal/errors');
 constutil=require('util');
 constconstants=process.binding('constants').os.signals;
 
@@ -180,7 +181,7 @@ function setupKillAndExit(){
 }
 
 if(err)
-throwutil._errnoException(err,'kill');
+throwerrors.errnoException(err,'kill');
 
 returntrue;
 };
@@ -211,7 +212,7 @@ function setupSignalHandlers(){
 consterr=wrap.start(signum);
 if(err){
 wrap.close();
-throwutil._errnoException(err,'uv_signal_start');
+throwerrors.errnoException(err,'uv_signal_start');
 }
 
 signalWraps[type]=wrap;

lib/net.js

@@ -48,8 +48,8 @@ const dns = require('dns');
 // reasons it's lazy loaded.
 varcluster=null;
 
-consterrnoException=util._errnoException;
-constexceptionWithHostPort=util._exceptionWithHostPort;
+consterrnoException=errors.errnoException;
+constexceptionWithHostPort=errors.exceptionWithHostPort;
 
 functionnoop(){}
 

lib/tty.js

@@ -21,11 +21,9 @@
 
 'use strict';
 
-constutil=require('util');
+const{ inherits, _extend }=require('util');
 constnet=require('net');
 const{TTY, isTTY }=process.binding('tty_wrap');
-const{ inherits }=util;
-consterrnoException=util._errnoException;
 consterrors=require('internal/errors');
 constreadline=require('readline');
 
@@ -40,7 +38,7 @@ function ReadStream(fd, options){
 if(fd>>0!==fd||fd<0)
 thrownewerrors.RangeError('ERR_INVALID_FD',fd);
 
-options=util._extend({
+options=_extend({
 highWaterMark: 0,
 readable: true,
 writable: false,
@@ -99,7 +97,7 @@ WriteStream.prototype._refreshSize = function(){
 varwinSize=newArray(2);
 varerr=this._handle.getWindowSize(winSize);
 if(err){
-this.emit('error',errnoException(err,'getWindowSize'));
+this.emit('error',errors.errnoException(err,'getWindowSize'));
 return;
 }
 varnewCols=winSize[0];