net: allow reading data into a static buffer

Co-Authored-By: Anna Henningsen <anna@addaleax.net>

PR-URL: https://github.com/nodejs/node/pull/25436
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

1 files changed, 186 insertions, 0 deletions

diff --git a/test/parallel/test-net-onread-static-buffer.js b/test/parallel/test-net-onread-static-buffer.js
new file mode 100644
index 0000000000..ce722f69cd
--- /dev/null
+++ b/test/parallel/test-net-onread-static-buffer.js
@@ -0,0 +1,186 @@
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+const net = require('net');
+
+const message = Buffer.from('hello world');
+
+// Test typical usage
+net.createServer(common.mustCall(function(socket) {
+  this.close();
+  socket.end(message);
+})).listen(0, function() {
+  let received = 0;
+  const buffers = [];
+  const sockBuf = Buffer.alloc(8);
+  net.connect({
+    port: this.address().port,
+    onread: {
+      buffer: sockBuf,
+      callback: function(nread, buf) {
+        assert.strictEqual(buf, sockBuf);
+        received += nread;
+        buffers.push(Buffer.from(buf.slice(0, nread)));
+      }
+    }
+  }).on('data', common.mustNotCall()).on('end', common.mustCall(() => {
+    assert.strictEqual(received, message.length);
+    assert.deepStrictEqual(Buffer.concat(buffers), message);
+  }));
+});
+
+// Test Uint8Array support
+net.createServer(common.mustCall(function(socket) {
+  this.close();
+  socket.end(message);
+})).listen(0, function() {
+  let received = 0;
+  let incoming = new Uint8Array(0);
+  const sockBuf = new Uint8Array(8);
+  net.connect({
+    port: this.address().port,
+    onread: {
+      buffer: sockBuf,
+      callback: function(nread, buf) {
+        assert.strictEqual(buf, sockBuf);
+        received += nread;
+        const newIncoming = new Uint8Array(incoming.length + nread);
+        newIncoming.set(incoming);
+        newIncoming.set(buf.slice(0, nread), incoming.length);
+        incoming = newIncoming;
+      }
+    }
+  }).on('data', common.mustNotCall()).on('end', common.mustCall(() => {
+    assert.strictEqual(received, message.length);
+    assert.deepStrictEqual(incoming, new Uint8Array(message));
+  }));
+});
+
+// Test Buffer callback usage
+net.createServer(common.mustCall(function(socket) {
+  this.close();
+  socket.end(message);
+})).listen(0, function() {
+  let received = 0;
+  const incoming = [];
+  const bufPool = [ Buffer.alloc(2), Buffer.alloc(2), Buffer.alloc(2) ];
+  let bufPoolIdx = -1;
+  let bufPoolUsage = 0;
+  net.connect({
+    port: this.address().port,
+    onread: {
+      buffer: () => {
+        ++bufPoolUsage;
+        bufPoolIdx = (bufPoolIdx + 1) % bufPool.length;
+        return bufPool[bufPoolIdx];
+      },
+      callback: function(nread, buf) {
+        assert.strictEqual(buf, bufPool[bufPoolIdx]);
+        received += nread;
+        incoming.push(Buffer.from(buf.slice(0, nread)));
+      }
+    }
+  }).on('data', common.mustNotCall()).on('end', common.mustCall(() => {
+    assert.strictEqual(received, message.length);
+    assert.deepStrictEqual(Buffer.concat(incoming), message);
+    assert.strictEqual(bufPoolUsage, 7);
+  }));
+});
+
+// Test Uint8Array callback support
+net.createServer(common.mustCall(function(socket) {
+  this.close();
+  socket.end(message);
+})).listen(0, function() {
+  let received = 0;
+  let incoming = new Uint8Array(0);
+  const bufPool = [ new Uint8Array(2), new Uint8Array(2), new Uint8Array(2) ];
+  let bufPoolIdx = -1;
+  let bufPoolUsage = 0;
+  net.connect({
+    port: this.address().port,
+    onread: {
+      buffer: () => {
+        ++bufPoolUsage;
+        bufPoolIdx = (bufPoolIdx + 1) % bufPool.length;
+        return bufPool[bufPoolIdx];
+      },
+      callback: function(nread, buf) {
+        assert.strictEqual(buf, bufPool[bufPoolIdx]);
+        received += nread;
+        const newIncoming = new Uint8Array(incoming.length + nread);
+        newIncoming.set(incoming);
+        newIncoming.set(buf.slice(0, nread), incoming.length);
+        incoming = newIncoming;
+      }
+    }
+  }).on('data', common.mustNotCall()).on('end', common.mustCall(() => {
+    assert.strictEqual(received, message.length);
+    assert.deepStrictEqual(incoming, new Uint8Array(message));
+    assert.strictEqual(bufPoolUsage, 7);
+  }));
+});
+
+// Test explicit socket pause
+net.createServer(common.mustCall(function(socket) {
+  this.close();
+  socket.end(message);
+})).listen(0, function() {
+  let received = 0;
+  const buffers = [];
+  const sockBuf = Buffer.alloc(8);
+  let paused = false;
+  net.connect({
+    port: this.address().port,
+    onread: {
+      buffer: sockBuf,
+      callback: function(nread, buf) {
+        assert.strictEqual(paused, false);
+        assert.strictEqual(buf, sockBuf);
+        received += nread;
+        buffers.push(Buffer.from(buf.slice(0, nread)));
+        paused = true;
+        this.pause();
+        setTimeout(() => {
+          paused = false;
+          this.resume();
+        }, 100);
+      }
+    }
+  }).on('data', common.mustNotCall()).on('end', common.mustCall(() => {
+    assert.strictEqual(received, message.length);
+    assert.deepStrictEqual(Buffer.concat(buffers), message);
+  }));
+});
+
+// Test implicit socket pause
+net.createServer(common.mustCall(function(socket) {
+  this.close();
+  socket.end(message);
+})).listen(0, function() {
+  let received = 0;
+  const buffers = [];
+  const sockBuf = Buffer.alloc(8);
+  let paused = false;
+  net.connect({
+    port: this.address().port,
+    onread: {
+      buffer: sockBuf,
+      callback: function(nread, buf) {
+        assert.strictEqual(paused, false);
+        assert.strictEqual(buf, sockBuf);
+        received += nread;
+        buffers.push(Buffer.from(buf.slice(0, nread)));
+        paused = true;
+        setTimeout(() => {
+          paused = false;
+          this.resume();
+        }, 100);
+        return false;
+      }
+    }
+  }).on('data', common.mustNotCall()).on('end', common.mustCall(() => {
+    assert.strictEqual(received, message.length);
+    assert.deepStrictEqual(Buffer.concat(buffers), message);
+  }));
+});