test: add common/udppair utility

Extracted from the QUIC PR. This adds a utility used to
deterministically test UDP traffic. It is currently only
used by the experimental QUIC implementation. Separated
out on request to make review easier.

PR-URL: https://github.com/nodejs/node/pull/33380
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>

1 files changed, 218 insertions, 0 deletions

diff --git a/src/js_udp_wrap.cc b/src/js_udp_wrap.cc
new file mode 100644
index 00000000000..c5168314118
--- /dev/null
+++ b/src/js_udp_wrap.cc
@@ -0,0 +1,218 @@
+#include "udp_wrap.h"
+#include "async_wrap-inl.h"
+#include "node_errors.h"
+#include "node_sockaddr-inl.h"
+
+#include <algorithm>
+
+namespace node {
+
+using errors::TryCatchScope;
+using v8::Array;
+using v8::Context;
+using v8::FunctionCallbackInfo;
+using v8::FunctionTemplate;
+using v8::HandleScope;
+using v8::Int32;
+using v8::Local;
+using v8::Object;
+using v8::String;
+using v8::Value;
+
+// JSUDPWrap is a testing utility used by test/common/udppair.js
+// to simulate UDP traffic deterministically in Node.js tests.
+class JSUDPWrap final : public UDPWrapBase, public AsyncWrap {
+ public:
+  JSUDPWrap(Environment* env, Local<Object> obj);
+
+  int RecvStart() override;
+  int RecvStop() override;
+  ssize_t Send(uv_buf_t* bufs,
+               size_t nbufs,
+               const sockaddr* addr) override;
+  SocketAddress GetPeerName() override;
+  SocketAddress GetSockName() override;
+  AsyncWrap* GetAsyncWrap() override { return this; }
+
+  static void New(const FunctionCallbackInfo<Value>& args);
+  static void EmitReceived(const FunctionCallbackInfo<Value>& args);
+  static void OnSendDone(const FunctionCallbackInfo<Value>& args);
+  static void OnAfterBind(const FunctionCallbackInfo<Value>& args);
+
+  static void Initialize(Local<Object> target,
+                         Local<Value> unused,
+                         Local<Context> context,
+                         void* priv);
+  SET_NO_MEMORY_INFO()
+  SET_MEMORY_INFO_NAME(JSUDPWrap)
+  SET_SELF_SIZE(JSUDPWrap)
+};
+
+JSUDPWrap::JSUDPWrap(Environment* env, Local<Object> obj)
+  : AsyncWrap(env, obj, PROVIDER_JSUDPWRAP) {
+  MakeWeak();
+
+  obj->SetAlignedPointerInInternalField(
+      kUDPWrapBaseField, static_cast<UDPWrapBase*>(this));
+}
+
+int JSUDPWrap::RecvStart() {
+  HandleScope scope(env()->isolate());
+  Context::Scope context_scope(env()->context());
+  TryCatchScope try_catch(env());
+  Local<Value> value;
+  int32_t value_int = UV_EPROTO;
+  if (!MakeCallback(env()->onreadstart_string(), 0, nullptr).ToLocal(&value) ||
+      !value->Int32Value(env()->context()).To(&value_int)) {
+    if (try_catch.HasCaught() && !try_catch.HasTerminated())
+      errors::TriggerUncaughtException(env()->isolate(), try_catch);
+  }
+  return value_int;
+}
+
+int JSUDPWrap::RecvStop() {
+  HandleScope scope(env()->isolate());
+  Context::Scope context_scope(env()->context());
+  TryCatchScope try_catch(env());
+  Local<Value> value;
+  int32_t value_int = UV_EPROTO;
+  if (!MakeCallback(env()->onreadstop_string(), 0, nullptr).ToLocal(&value) ||
+      !value->Int32Value(env()->context()).To(&value_int)) {
+    if (try_catch.HasCaught() && !try_catch.HasTerminated())
+      errors::TriggerUncaughtException(env()->isolate(), try_catch);
+  }
+  return value_int;
+}
+
+ssize_t JSUDPWrap::Send(uv_buf_t* bufs,
+                        size_t nbufs,
+                        const sockaddr* addr) {
+  HandleScope scope(env()->isolate());
+  Context::Scope context_scope(env()->context());
+  TryCatchScope try_catch(env());
+  Local<Value> value;
+  int64_t value_int = UV_EPROTO;
+  size_t total_len = 0;
+
+  MaybeStackBuffer<Local<Value>, 16> buffers(nbufs);
+  for (size_t i = 0; i < nbufs; i++) {
+    buffers[i] = Buffer::Copy(env(), bufs[i].base, bufs[i].len)
+        .ToLocalChecked();
+    total_len += bufs[i].len;
+  }
+
+  Local<Value> args[] = {
+    listener()->CreateSendWrap(total_len)->object(),
+    Array::New(env()->isolate(), buffers.out(), nbufs),
+    AddressToJS(env(), addr)
+  };
+
+  if (!MakeCallback(env()->onwrite_string(), arraysize(args), args)
+          .ToLocal(&value) ||
+      !value->IntegerValue(env()->context()).To(&value_int)) {
+    if (try_catch.HasCaught() && !try_catch.HasTerminated())
+      errors::TriggerUncaughtException(env()->isolate(), try_catch);
+  }
+  return value_int;
+}
+
+SocketAddress JSUDPWrap::GetPeerName() {
+  SocketAddress ret;
+  CHECK(SocketAddress::New(AF_INET, "127.0.0.1", 1337, &ret));
+  return ret;
+}
+
+SocketAddress JSUDPWrap::GetSockName() {
+  SocketAddress ret;
+  CHECK(SocketAddress::New(AF_INET, "127.0.0.1", 1337, &ret));
+  return ret;
+}
+
+void JSUDPWrap::New(const FunctionCallbackInfo<Value>& args) {
+  Environment* env = Environment::GetCurrent(args);
+  CHECK(args.IsConstructCall());
+  new JSUDPWrap(env, args.Holder());
+}
+
+void JSUDPWrap::EmitReceived(const FunctionCallbackInfo<Value>& args) {
+  JSUDPWrap* wrap;
+  ASSIGN_OR_RETURN_UNWRAP(&wrap, args.Holder());
+  Environment* env = wrap->env();
+
+  ArrayBufferViewContents<char> buffer(args[0]);
+  const char* data = buffer.data();
+  int len = buffer.length();
+
+  CHECK(args[1]->IsInt32());   // family
+  CHECK(args[2]->IsString());  // address
+  CHECK(args[3]->IsInt32());   // port
+  CHECK(args[4]->IsInt32());   // flags
+  int family = args[1].As<Int32>()->Value() == 4 ? AF_INET : AF_INET6;
+  Utf8Value address(env->isolate(), args[2]);
+  int port = args[3].As<Int32>()->Value();
+  int flags = args[3].As<Int32>()->Value();
+
+  sockaddr_storage addr;
+  CHECK_EQ(sockaddr_for_family(family, *address, port, &addr), 0);
+
+  // Repeatedly ask the stream's owner for memory, copy the data that we
+  // just read from JS into those buffers and emit them as reads.
+  while (len != 0) {
+    uv_buf_t buf = wrap->listener()->OnAlloc(len);
+    ssize_t avail = std::min<size_t>(buf.len, len);
+    memcpy(buf.base, data, avail);
+    data += avail;
+    len -= avail;
+    wrap->listener()->OnRecv(
+        avail, buf, reinterpret_cast<sockaddr*>(&addr), flags);
+  }
+}
+
+void JSUDPWrap::OnSendDone(const FunctionCallbackInfo<Value>& args) {
+  JSUDPWrap* wrap;
+  ASSIGN_OR_RETURN_UNWRAP(&wrap, args.Holder());
+
+  CHECK(args[0]->IsObject());
+  CHECK(args[1]->IsInt32());
+  ReqWrap<uv_udp_send_t>* req_wrap;
+  ASSIGN_OR_RETURN_UNWRAP(&req_wrap, args[0].As<Object>());
+  int status = args[1].As<Int32>()->Value();
+
+  wrap->listener()->OnSendDone(req_wrap, status);
+}
+
+void JSUDPWrap::OnAfterBind(const FunctionCallbackInfo<Value>& args) {
+  JSUDPWrap* wrap;
+  ASSIGN_OR_RETURN_UNWRAP(&wrap, args.Holder());
+
+  wrap->listener()->OnAfterBind();
+}
+
+void JSUDPWrap::Initialize(Local<Object> target,
+                           Local<Value> unused,
+                           Local<Context> context,
+                           void* priv) {
+  Environment* env = Environment::GetCurrent(context);
+
+  Local<FunctionTemplate> t = env->NewFunctionTemplate(New);
+  Local<String> js_udp_wrap_string =
+      FIXED_ONE_BYTE_STRING(env->isolate(), "JSUDPWrap");
+  t->SetClassName(js_udp_wrap_string);
+  t->InstanceTemplate()
+    ->SetInternalFieldCount(UDPWrapBase::kUDPWrapBaseField + 1);
+  t->Inherit(AsyncWrap::GetConstructorTemplate(env));
+
+  UDPWrapBase::AddMethods(env, t);
+  env->SetProtoMethod(t, "emitReceived", EmitReceived);
+  env->SetProtoMethod(t, "onSendDone", OnSendDone);
+  env->SetProtoMethod(t, "onAfterBind", OnAfterBind);
+
+  target->Set(env->context(),
+              js_udp_wrap_string,
+              t->GetFunction(context).ToLocalChecked()).Check();
+}
+
+
+}  // namespace node
+
+NODE_MODULE_CONTEXT_AWARE_INTERNAL(js_udp_wrap, node::JSUDPWrap::Initialize)