lib: use FastBuffer for empty buffer allocation

gurgunday · RafaelGSS · commit 1a0c3dddb9ec · 2026-01-13T10:04:02.000-03:00
PR-URL: #60558 Reviewed-By: Luigi Pinca <luigipinca@gmail.com> Reviewed-By: Juan José Arboleda <soyjuanarbol@gmail.com>
diff --git a/lib/buffer.js b/lib/buffer.js
@@ -352,13 +352,13 @@ Buffer.copyBytesFrom = function copyBytesFrom(view, offset, length) {
 
 const viewLength = TypedArrayPrototypeGetLength(view);
 if (viewLength === 0) {
- return Buffer.alloc(0);
+ return new FastBuffer();
 }
 
 if (offset !== undefined || length !== undefined) {
 if (offset !== undefined) {
 validateInteger(offset, 'offset', 0);
- if (offset >= viewLength) return Buffer.alloc(0);
+ if (offset >= viewLength) return new FastBuffer();
 } else {
 offset = 0;
 }
@@ -1262,7 +1262,7 @@ if (internalBinding('config').hasIntl) {
 throw new ERR_INVALID_ARG_TYPE('source',
 ['Buffer', 'Uint8Array'], source);
 }
- if (source.length === 0) return Buffer.alloc(0);
+ if (source.length === 0) return new FastBuffer();
 
 fromEncoding = normalizeEncoding(fromEncoding) || fromEncoding;
 toEncoding = normalizeEncoding(toEncoding) || toEncoding;
diff --git a/lib/dgram.js b/lib/dgram.js
@@ -73,6 +73,7 @@ const {
 defaultTriggerAsyncIdScope,
 symbols: { async_id_symbol, owner_symbol },
 } = require('internal/async_hooks');
+const { FastBuffer } = require('internal/buffer');
 const { UV_UDP_REUSEADDR } = internalBinding('constants').os;
 
 const {
@@ -688,7 +689,7 @@ Socket.prototype.send = function(buffer,
 this.bind({ port: 0, exclusive: true }, null);
 
 if (list.length === 0)
- ArrayPrototypePush(list, Buffer.alloc(0));
+ ArrayPrototypePush(list, new FastBuffer());
 
 // If the socket hasn't been bound yet, push the outbound packet onto the
 // send queue and send after binding is complete.
diff --git a/lib/internal/debugger/inspect_client.js b/lib/internal/debugger/inspect_client.js
@@ -16,6 +16,7 @@ const { ERR_DEBUGGER_ERROR } = require('internal/errors').codes;
 const { EventEmitter, once } = require('events');
 const http = require('http');
 const { URL } = require('internal/url');
+const { FastBuffer } = require('internal/buffer');
 
 const debuglog = require('internal/util/debuglog').debuglog('inspect');
 
@@ -79,7 +80,7 @@ function encodeFrameHybi17(payload) {
 additionalLength[0] = (dataLength & 0xFF00) >> 8;
 additionalLength[1] = dataLength & 0xFF;
 } else {
- additionalLength = Buffer.alloc(0);
+ additionalLength = new FastBuffer();
 singleByteLength = dataLength;
 }
 
@@ -233,7 +234,7 @@ class Client extends EventEmitter {
 this._lastId = 0;
 this._socket = null;
 this._pending = {};
- this._unprocessed = Buffer.alloc(0);
+ this._unprocessed = new FastBuffer();
 }
 
 callMethod(method, params) {
diff --git a/lib/internal/streams/readable.js b/lib/internal/streams/readable.js
@@ -1605,7 +1605,7 @@ function fromList(n, state) {
 buf[idx++] = null;
 }
 } else if (len - idx === 0) {
- ret = Buffer.alloc(0);
+ ret = new FastBuffer();
 } else if (len - idx === 1) {
 ret = buf[idx];
 buf[idx++] = null;
diff --git a/lib/internal/test_runner/runner.js b/lib/internal/test_runner/runner.js
@@ -78,6 +78,7 @@ const {
 kTestTimeoutFailure,
 Test,
 } = require('internal/test_runner/test');
+const { FastBuffer } = require('internal/buffer');
 
 const {
 convertStringToRegExp,
@@ -324,7 +325,7 @@ class FileTest extends Test {
 // This method is called when it is known that there is at least one message
 let bufferHead = this.#rawBuffer[0];
 let headerIndex = bufferHead.indexOf(v8Header);
- let nonSerialized = Buffer.alloc(0);
+ let nonSerialized = new FastBuffer();
 
 while (bufferHead && headerIndex !== 0) {
 const nonSerializedData = headerIndex === -1 ?
diff --git a/lib/zlib.js b/lib/zlib.js
@@ -70,6 +70,7 @@ const {
 validateUint32,
 validateFiniteNumber,
 } = require('internal/validators');
+const { FastBuffer } = require('internal/buffer');
 
 const kFlushFlag = Symbol('kFlushFlag');
 const kError = Symbol('kError');
@@ -150,7 +151,7 @@ function zlibBufferOnError(err) {
 function zlibBufferOnEnd() {
 let buf;
 if (this.nread === 0) {
- buf = Buffer.alloc(0);
+ buf = new FastBuffer();
 } else {
 const bufs = this.buffers;
 buf = (bufs.length === 1 ? bufs[0] : Buffer.concat(bufs, this.nread));
@@ -301,7 +302,7 @@ ZlibBase.prototype.reset = function() {
 * @returns {void}
 */
 ZlibBase.prototype._flush = function(callback) {
- this._transform(Buffer.alloc(0), '', callback);
+ this._transform(new FastBuffer(), '', callback);
 };
 
 /**
@@ -476,7 +477,7 @@ function processChunkSync(self, chunk, flushFlag) {
 _close(self);
 
 if (nread === 0)
- return Buffer.alloc(0);
+ return new FastBuffer();
 
 return (buffers.length === 1 ? buffers[0] : Buffer.concat(buffers, nread));
 }

-Original file line number
+Diff line change
 constviewLength=TypedArrayPrototypeGetLength(view);
 if(viewLength===0){
 -returnBuffer.alloc(0);
 +returnnewFastBuffer();
+}
 if(offset!==undefined||length!==undefined){
 if(offset!==undefined){
 validateInteger(offset,'offset',0);
 -if(offset>=viewLength)returnBuffer.alloc(0);
 +if(offset>=viewLength)returnnewFastBuffer();
 }else{
 offset=0;
+}
 thrownewERR_INVALID_ARG_TYPE('source',
 ['Buffer','Uint8Array'],source);
+}
 -if(source.length===0)returnBuffer.alloc(0);
 +if(source.length===0)returnnewFastBuffer();
 fromEncoding=normalizeEncoding(fromEncoding)||fromEncoding;
 toEncoding=normalizeEncoding(toEncoding)||toEncoding;
-Original file line number
+Diff line change
  defaultTriggerAsyncIdScope,
 symbols: { async_id_symbol, owner_symbol },
 }=require('internal/async_hooks');
 +const{ FastBuffer }=require('internal/buffer');
 const{UV_UDP_REUSEADDR}=internalBinding('constants').os;
 const{
 this.bind({port: 0,exclusive: true},null);
 if(list.length===0)
 -ArrayPrototypePush(list,Buffer.alloc(0));
 +ArrayPrototypePush(list,newFastBuffer());
 // If the socket hasn't been bound yet, push the outbound packet onto the
 // send queue and send after binding is complete.
-Original file line number
+Diff line change
 const{ EventEmitter, once }=require('events');
 consthttp=require('http');
 const{URL}=require('internal/url');
 +const{ FastBuffer }=require('internal/buffer');
 constdebuglog=require('internal/util/debuglog').debuglog('inspect');
 additionalLength[0]=(dataLength&0xFF00)>>8;
 additionalLength[1]=dataLength&0xFF;
 }else{
 -additionalLength=Buffer.alloc(0);
 +additionalLength=newFastBuffer();
 singleByteLength=dataLength;
+}
 this._lastId=0;
 this._socket=null;
 this._pending={};
 -this._unprocessed=Buffer.alloc(0);
 +this._unprocessed=newFastBuffer();
+}
 callMethod(method,params){
Original file line number	Diff line number	Diff line change
`@@ -1605,7 +1605,7 @@ function fromList(n, state) {`
`1605`	`1605`	`buf[idx++]=null;`
`1606`	`1606`	`}`
`1607`	`1607`	`}elseif(len-idx===0){`
`1608`		`-ret=Buffer.alloc(0);`
	`1608`	`+ret=newFastBuffer();`
`1609`	`1609`	`}elseif(len-idx===1){`
`1610`	`1610`	`ret=buf[idx];`
`1611`	`1611`	`buf[idx++]=null;`
-Original file line number
+Diff line change
  kTestTimeoutFailure,
  Test,
 }=require('internal/test_runner/test');
 +const{ FastBuffer }=require('internal/buffer');
 const{
  convertStringToRegExp,
 // This method is called when it is known that there is at least one message
 letbufferHead=this.#rawBuffer[0];
 letheaderIndex=bufferHead.indexOf(v8Header);
 -letnonSerialized=Buffer.alloc(0);
 +letnonSerialized=newFastBuffer();
 while(bufferHead&&headerIndex!==0){
 constnonSerializedData=headerIndex===-1 ?
-Original file line number
+Diff line change
  validateUint32,
  validateFiniteNumber,
 }=require('internal/validators');
 +const{ FastBuffer }=require('internal/buffer');
 constkFlushFlag=Symbol('kFlushFlag');
 constkError=Symbol('kError');
 functionzlibBufferOnEnd(){
 letbuf;
 if(this.nread===0){
 -buf=Buffer.alloc(0);
 +buf=newFastBuffer();
 }else{
 constbufs=this.buffers;
 buf=(bufs.length===1 ? bufs[0] : Buffer.concat(bufs,this.nread));
  * @returns {void}
  */
 ZlibBase.prototype._flush=function(callback){
 -this._transform(Buffer.alloc(0),'',callback);
 +this._transform(newFastBuffer(),'',callback);
 };
 /**
 _close(self);
 if(nread===0)
 -returnBuffer.alloc(0);
 +returnnewFastBuffer();
 return(buffers.length===1 ? buffers[0] : Buffer.concat(buffers,nread));
+}