internal: add custom dir support for heapsnapshot-signal

Author: MrJithil

lib/internal/process/pre_execution.js

@@ -8,6 +8,7 @@ const {
   ObjectGetOwnPropertyDescriptor,
   SafeMap,
   StringPrototypeStartsWith,
+  DateNow,
   globalThis,
 } = primordials;
 
@@ -365,6 +366,7 @@ function initializeReportSignalHandlers() {
 
 function initializeHeapSnapshotSignalHandlers() {
   const signal = getOptionValue('--heapsnapshot-signal');
+  const diagnosticDir = getOptionValue('--diagnostic-dir');
 
   if (!signal)
     return;
@@ -373,7 +375,8 @@ function initializeHeapSnapshotSignalHandlers() {
   const { writeHeapSnapshot } = require('v8');
 
   function doWriteHeapSnapshot() {
-    writeHeapSnapshot();
+    const heapSnapshotFilename = getHeapSnapshotFilename(diagnosticDir);
+    writeHeapSnapshot(heapSnapshotFilename);
   }
   process.on(signal, doWriteHeapSnapshot);
 
@@ -650,6 +653,11 @@ function markBootstrapComplete() {
   internalBinding('performance').markBootstrapComplete();
 }
 
+function getHeapSnapshotFilename(diagnosticDir) {
+  if (!diagnosticDir) return undefined;
+  return `${diagnosticDir}/Heap.${DateNow()}.heapsnapshot`;
+}
+
 module.exports = {
   setupUserModules,
   prepareMainThreadExecution,