refactor: setup child process pipe in Rust (#21579)

Avoid passing the fd into JS and back into Rust. Instead we setup the
child's end of the pipe directly using a special Rust op.

2 files changed, 4 insertions, 3 deletions

diff --git a/ext/node/polyfills/02_init.js b/ext/node/polyfills/02_init.js
index e5a0279a5..8d9405c16 100644
--- a/ext/node/polyfills/02_init.js
+++ b/ext/node/polyfills/02_init.js
@@ -12,7 +12,6 @@ let initialized = false;
 function initialize(
   usesLocalNodeModulesDir,
   argv0,
-  ipcFd,
 ) {
   if (initialized) {
     throw Error("Node runtime already initialized");
@@ -38,7 +37,7 @@ function initialize(
   // but it's the only way to get `args` and `version` and this point.
   internals.__bootstrapNodeProcess(argv0, Deno.args, Deno.version);
   internals.__initWorkerThreads();
-  internals.__setupChildProcessIpcChannel(ipcFd);
+  internals.__setupChildProcessIpcChannel();
   // `Deno[Deno.internal].requireImpl` will be unreachable after this line.
   delete internals.requireImpl;
 }
diff --git a/ext/node/polyfills/child_process.ts b/ext/node/polyfills/child_process.ts
index c7d007f46..da82546f6 100644
--- a/ext/node/polyfills/child_process.ts
+++ b/ext/node/polyfills/child_process.ts
@@ -49,6 +49,7 @@ import {
 } from "ext:deno_node/internal/util.mjs";
 
 const { core } = globalThis.__bootstrap;
+const ops = core.ops;
 
 const MAX_BUFFER = 1024 * 1024;
 
@@ -822,7 +823,8 @@ export function execFileSync(
   return ret.stdout as string | Buffer;
 }
 
-function setupChildProcessIpcChannel(fd: number) {
+function setupChildProcessIpcChannel() {
+  const fd = ops.op_node_child_ipc_pipe();
   if (typeof fd != "number" || fd < 0) return;
   setupChannel(process, fd);
 }