TODO/XXX/FIXME comments in src directory #4641

    // Waiting for client, do not send anything just yet
    // TODO(indutny): move this to js-land
    if (a->wait_) {
      a->messages_.PushFront(msg);  // Push message back into the ready queue.

  };

  // TODO(indutny): Verify that there are no races
  State state_;

    const v8::PropertyCallbackInfo<T>& info) {
  ASSERT(info.Data()->IsExternal());
  // XXX(bnoordhuis) Work around a g++ 4.9.2 template type inferrer bug
  // when the expression is written as info.Data().As<v8::External>().
  v8::Local<v8::Value> data = info.Data();

class Environment;

// TODO(bnoordhuis) Rename struct, the ares_ prefix implies it's part
// of the c-ares API while the _t suffix implies it's a typedef.
struct ares_task_t {

static void IdleImmediateDummy(uv_idle_t* handle) {
  // Do nothing. Only for maintaining event loop.
  // TODO(bnoordhuis) Maybe make libuv accept nullptr idle callbacks.
}

...
  Local<String> path_string;
  if (path != nullptr) {
    // FIXME(bnoordhuis) It's questionable to interpret the file path as UTF-8.
    path_string = String::NewFromUtf8(env->isolate(), path);
  }
...
  Local<Object> e = Exception::Error(js_msg)->ToObject(isolate);

  // TODO(piscisaureus) errno should probably go; the user has no way of
  // knowing which uv errno value maps to which error.
  e->Set(env->errno_string(), Integer::New(isolate, errorno));
...
  bool has_domain = false;

  // TODO(trevnorris): Adding "_asyncQueue" to the "this" in the init callback
  // is a horrible way to detect usage. Rethink how detection should happen.
  if (recv->IsObject()) {
...
// Used to load 'module.node' dynamically shared objects.
//
// FIXME(bnoordhuis) Not multi-context ready. TBD how to resolve the conflict
// when two contexts try to load the same shared object. Maybe have a shadow
// cache that's a plain C list or hash table that's shared across contexts?
...
void FatalException(Isolate* isolate, const TryCatch& try_catch) {
  HandleScope scope(isolate);
  // TODO(bajtos) do not call FatalException if try_catch is verbose
  // (requires V8 API to expose getter for try_catch.is_verbose_)
  FatalException(isolate, try_catch.Exception(), try_catch.Message());
...
                               const PropertyCallbackInfo<void>& info) {
  node::Utf8Value title(info.GetIsolate(), value);
  // TODO(piscisaureus): protect with a lock
  uv_set_process_title(*title);
}
...

  obj->Set(env->uv_string(), True(env->isolate()));
  // TODO(bnoordhuis) ping libuv
  obj->Set(env->ipv6_lc_string(), True(env->isolate()));

...
// Called from V8 Debug Agent TCP thread.
static void DispatchMessagesDebugAgentCallback(Environment* env) {
  // TODO(indutny): move async handle to environment
  uv_async_send(&dispatch_debug_messages_async);
}
...

static int RegisterDebugSignalHandler() {
  // FIXME(bnoordhuis) Should be per-isolate or per-context, not global.
  RegisterSignalHandler(SIGUSR1, EnableDebugSignalHandler);
  // Unblock SIGUSR1.  A pending SIGUSR1 signal will now be delivered.
...
  ParseArgs(argc, argv, exec_argc, exec_argv, &v8_argc, &v8_argv);

  // TODO(bnoordhuis) Intercept --prof arguments and start the CPU profiler
  // manually?  That would give us a little more control over its runtime
  // behavior but it could also interfere with the user's intentions in ways
...


// TODO(bnoordhuis) Turn into per-context event.
void RunAtExit(Environment* env) {
  AtExitCallback* p = at_exit_functions_;
...
  // epoll_wait() and friends so profiling tools can filter it out.  The samples
  // still end up in v8.log but with state=IDLE rather than state=EXTERNAL.
  // TODO(bnoordhuis) Depends on a libuv implementation detail that we should
  // probably fortify in the API contract, namely that the last started prepare
  // or check watcher runs first.  It's not 100% foolproof; if an add-on starts

#ifdef _WIN32
// TODO(tjfontaine) consider changing the usage of ssize_t to ptrdiff_t
#if !defined(_SSIZE_T_) && !defined(_SSIZE_T_DEFINED)
typedef intptr_t ssize_t;

            })) {

          // XXX Fix this terrible hack!
          //
          // Give the client program a few ticks to connect.
...
          if (!process.emit('unhandledRejection', reason, promise)) {
            // Nobody is listening.
            // TODO(petkaantonov) Take some default action, see #830
          } else {
            hadListeners = true;
...
      // Load tcp_wrap to avoid situation where we might immediately receive
      // a message.
      // FIXME is this really necessary?
      process.binding('tcp_wrap');

  // XXX(isaacs): This function only exists because of a shortcoming of
  // the V8 SetNamedPropertyHandler function.
  //

    char fingerprint[EVP_MAX_MD_SIZE * 3];

    // TODO(indutny): Unify it with buffer's code
    for (i = 0; i < md_size; i++) {
      fingerprint[3*i] = hex[(md[i] & 0xf0) >> 4];
...


// TODO(indutny): Split it into multiple smaller functions
template <class Base>
void SSLWrap<Base>::GetPeerCertificate(
...
  Base* w = Unwrap<Base>(args.Holder());

  // XXX(bnoordhuis) The UNABLE_TO_GET_ISSUER_CERT error when there is no
  // peer certificate is questionable but it's compatible with what was
  // here before.
...
    return args.GetReturnValue().SetNull();

  // XXX(bnoordhuis) X509_verify_cert_error_string() is not actually thread-safe
  // in the presence of invalid error codes.  Probably academical but something
  // to keep in mind if/when node ever grows multi-isolate capabilities.
...
    CHECK(err == SSL_ERROR_SSL || err == SSL_ERROR_SYSCALL);

    // XXX We need to drain the error queue for this thread or else OpenSSL
    // has the possibility of blocking connections? This problem is not well
    // understood. And we should be somehow propagating these errors up
...
  Environment* env = Environment::GetCurrent(args);

  // TODO(indutny): Support raw curves?
  CHECK(args[0]->IsString());
  node::Utf8Value curve(env->isolate(), args[0]);
...
  if (args[5]->IsFunction()) {
    obj->Set(env->ondone_string(), args[5]);
    // XXX(trevnorris): This will need to go with the rest of domains.
    if (env->in_domain())
      obj->Set(env->domain_string(), env->domain_array()->Get(0));
...
  if (args[1]->IsFunction()) {
    obj->Set(FIXED_ONE_BYTE_STRING(args.GetIsolate(), "ondone"), args[1]);
    // XXX(trevnorris): This will need to go with the rest of domains.
    if (env->in_domain())
      obj->Set(env->domain_string(), env->domain_array()->Get(0));
...


// FIXME(bnoordhuis) Handle global init correctly.
void InitCrypto(Local<Object> target,
                Local<Value> unused,

  bio->ptr = new NodeBIO();

  // XXX Why am I doing it?!
  bio->shutdown = 1;
  bio->init = 1;

  int fd = args[0]->Int32Value();

  // FIXME(bnoordhuis) It's questionable to reject non-ints here but still
  // allow implicit coercion from null or undefined to zero.  Probably best
  // handled in lib/fs.js.

    else if (on_heap_ || str_ + size_ != str) {
      // Non-consecutive input, make a copy on the heap.
      // TODO(bnoordhuis) Use slab allocation, O(n) allocs is bad.
      char* s = new char[size_ + size];
      memcpy(s, str_, size_);
...
    Local<Integer> nparsed_obj = Integer::New(env()->isolate(), nparsed);
    // If there was a parse error in one of the callbacks
    // TODO(bnoordhuis) What if there is an error on EOF?
    if (!parser_.upgrade && nparsed != len) {
      enum http_errno err = HTTP_PARSER_ERRNO(&parser_);

// TODO(bnoordhuis) share with TCPWrap?
class PipeConnectWrap : public ReqWrap<uv_connect_t> {
 public:
...


// TODO(bnoordhuis) maybe share with TCPWrap?
void PipeWrap::OnConnection(uv_stream_t* handle, int status) {
  PipeWrap* pipe_wrap = static_cast<PipeWrap*>(handle->data);
...
}

// TODO(bnoordhuis) Maybe share this with TCPWrap?
void PipeWrap::AfterConnect(uv_connect_t* req, int status) {
  PipeConnectWrap* req_wrap = static_cast<PipeConnectWrap*>(req->data);

    }

    // TODO(bnoordhuis) is this possible to do without mallocing ?

    // options.file

    object->Set(env->domain_string(), env->domain_array()->Get(0));

  // FIXME(bnoordhuis) The fact that a reinterpret_cast is needed is
  // arguably a good indicator that there should be more than one queue.
  env->req_wrap_queue()->PushBack(reinterpret_cast<ReqWrap<uv_req_t>*>(this));

 public:
  T req_;  // Must be last.  TODO(bnoordhuis) Make private.
};

  if (enc == HEX && string->Length() % 2 != 0)
    return false;
  // TODO(bnoordhuis) Add BASE64 check?
  return true;
}

  // Does the string match the encoding? Quick but non-exhaustive.
  // Example: a HEX string must have a length that's a multiple of two.
  // FIXME(bnoordhuis) IsMaybeValidString()? Naming things is hard...
  static bool IsValidString(v8::Isolate* isolate,
                            v8::Local<v8::String> string,

// TODO(bnoordhuis) share with StreamWrap::AfterWrite() in stream_wrap.cc
void UDPWrap::OnSend(uv_udp_send_t* req, int status) {
  SendWrap* req_wrap = static_cast<SendWrap*>(req->data);