From 0037a3e7f5a1e6c5f85495abf5d01fdd6928a793 Mon Sep 17 00:00:00 2001
From: Jacob Dufault <jacobdufault@gmail.com>
Date: Thu, 23 Mar 2017 22:20:08 -0700
Subject: [PATCH] Add TypedBidiMessageQueue

---
 command_line.cc                |  13 ++++
 indexer.cpp                    |  12 ++++
 src/typed_bidi_message_queue.h | 108 +++++++++++++++++++++++++++++++++
 3 files changed, 133 insertions(+)
 create mode 100644 src/typed_bidi_message_queue.h

diff --git a/command_line.cc b/command_line.cc
index 9bd75628..4642aff0 100644
--- a/command_line.cc
+++ b/command_line.cc
@@ -11,6 +11,8 @@
 #include "language_server_api.h"
 #include "test.h"
 
+#include "src/typed_bidi_message_queue.h"
+
 #include "third_party/tiny-process-library/process.hpp"
 
 #include "third_party/doctest/doctest/doctest.h"
@@ -1025,7 +1027,18 @@ void PreMain() {
   MessageRegistry::instance()->Register<In_WorkspaceSymbolRequest>();
 }
 
+struct MyMessageType {
+  static const lsMethodId id = lsMethodId::CancelRequest;
+};
+
 int main(int argc, char** argv) {
+  // TODO: real impl
+  const int kQueueSize = 128;
+  TypedBidiMessageQueue<lsMethodId, MyMessageType> t("foo", kQueueSize);
+  MyMessageType mm;
+  t.SendMessage(&t.for_client, lsMethodId::Initialize, &mm);
+  t.GetMessages(&t.for_client);
+
   bool loop = false;
   while (loop)
     std::this_thread::sleep_for(std::chrono::milliseconds(10));
diff --git a/indexer.cpp b/indexer.cpp
index 8a2064cf..8e5a6f03 100644
--- a/indexer.cpp
+++ b/indexer.cpp
@@ -1204,6 +1204,18 @@ void emptyIndexEntityReference(CXClientData client_data,
 IndexedFile Parse(std::string filename,
                   std::vector<std::string> args,
                   bool dump_ast) {
+  // TODO!!
+  // TODO!!
+  // TODO!!
+  // TODO!!: Strip useless defs from IndexedFile before returning
+  // TODO!!: Strip useless defs from IndexedFile before returning
+  // TODO!!: Strip useless defs from IndexedFile before returning
+  // TODO!!: Strip useless defs from IndexedFile before returning
+  // TODO!!: Strip useless defs from IndexedFile before returning
+  // TODO!!: Strip useless defs from IndexedFile before returning
+  // TODO!!
+  // TODO!!
+  // TODO!!
   clang_toggleCrashRecovery(1);
 
   args.push_back("-std=c++11");
diff --git a/src/typed_bidi_message_queue.h b/src/typed_bidi_message_queue.h
new file mode 100644
index 00000000..1b4485f4
--- /dev/null
+++ b/src/typed_bidi_message_queue.h
@@ -0,0 +1,108 @@
+#pragma once
+
+#include <functional>
+#include <iostream>
+#include <unordered_map>
+
+#include "buffer.h"
+#include "message_queue.h"
+#include "../serializer.h"
+
+// TypedBidiMessageQueue provides a type-safe server/client implementation on
+// top of a couple MessageQueue instances.
+template <typename TId, typename TMessage>
+struct TypedBidiMessageQueue {
+  using Serializer = std::function<void(Writer& visitor, TMessage& message)>;
+  using Deserializer =
+      std::function<std::unique_ptr<TMessage>(Reader& visitor)>;
+
+  TypedBidiMessageQueue(const std::string& name, size_t buffer_size)
+      : for_server(
+            Buffer::CreateSharedBuffer(name + "_for_server", buffer_size),
+            false /*buffer_has_data*/),
+        for_client(
+            Buffer::CreateSharedBuffer(name + "_for_client", buffer_size),
+            true /*buffer_has_data*/) {}
+
+  void RegisterId(TId id,
+                  const Serializer& serializer,
+                  const Deserializer& deseriaizer) {
+    assert(serializers_.find(id) == serializers_.end() &&
+           deserializers_.find(id) == deserializers_.end() &&
+           "Duplicate registration");
+
+    serializers_[id] = serializer;
+    deserializers_[id] = deserializer;
+  }
+
+  void SendMessage(MessageQueue* destination, TId id, TMessage* message) {
+    // Create writer.
+    rapidjson::StringBuffer output;
+    rapidjson::PrettyWriter<rapidjson::StringBuffer> writer(output);
+    writer.SetIndent(' ', 0);
+
+    // Serialize the message.
+    assert(serializers_.find(message->id) != serializers_.end() &&
+           "No registered serializer");
+    const Serializer& serializer = serializers_.find(id)->second;
+    serializer(writer, *message);
+
+    // Send message.
+    void* payload = malloc(sizeof(MessageHeader) + output.GetSize());
+    reinterpret_cast<MessageHeader*>(payload)->id = id;
+    memcpy(
+        (void*)(reinterpret_cast<const char*>(payload) + sizeof(MessageHeader)),
+        output.GetString(), output.GetSize());
+    destination->Enqueue(
+        Message(payload, sizeof(MessageHeader) + output.GetSize()));
+    free(payload);
+  }
+
+  // Retrieve all messages from the given |queue|.
+  std::vector<std::unique_ptr<TMessage>> GetMessages(
+      MessageQueue* queue) const {
+    assert(queue == &for_server || queue == &for_client);
+
+    std::vector<std::unique_ptr<Buffer>> messages = queue->DequeueAll();
+    std::vector<std::unique_ptr<TMessage>> result;
+    result.reserve(messages.size());
+
+    for (std::unique_ptr<Buffer>& buffer : messages) {
+      MessageHeader* header = reinterpret_cast<MessageHeader*>(buffer->data);
+
+      // Parse message content.
+      rapidjson::Document document;
+      document.Parse(
+          reinterpret_cast<const char*>(buffer->data) + sizeof(MessageHeader),
+          buffer->capacity - sizeof(MessageHeader));
+      bool has_error = document.HasParseError();
+      auto error = document.GetParseError();
+      if (has_error) {
+        std::cerr << "[FATAL]: Unable to parse IPC message" << std::endl;
+        exit(1);
+      }
+
+      // Deserialize it.
+      assert(deserializers_.find(header->id) != deserializers_.end() &&
+             "No registered deserializer");
+      const Deserializer& deserializer =
+          deserializers_.find(header->id)->second;
+      result.emplace_back(deserializer(document));
+    }
+
+    return result;
+  }
+
+  // Messages which the server process should handle.
+  MessageQueue for_server;
+  // Messages which the client process should handle.
+  MessageQueue for_client;
+
+ private:
+  struct MessageHeader {
+    TId id;
+  };
+
+  std::unordered_map<TId, Serializer> serializers_;
+  std::unordered_map<TId, Deserializer> deserializers_;
+};
\ No newline at end of file