more wip ipc refactor

command_line.cc

@@ -4,6 +4,7 @@
 
 #include "compilation_database_loader.h"
 #include "indexer.h"
+#include "ipc.h"
 #include "query.h"
 
 bool ParsePreferredSymbolLocation(const std::string& content, PreferredSymbolLocation* obj) {
@@ -94,7 +95,13 @@ indexer.exe --index-file /work2/chrome/src/chrome/foo.cc
 }
 */
 
-#include "ipc.h"
+
+struct IpcMessage_IsAlive : public IpcMessage<IpcMessage_IsAlive> {
+  static IpcMessageId id;
+};
+
+IpcMessageId IpcMessage_IsAlive::id = "IsAlive";
+
 
 void IndexerServerMain() {
   IpcServer ipc("language_server");
@@ -104,15 +111,13 @@ void IndexerServerMain() {
 
     std::cout << "Server has " << messages.size() << " messages" << std::endl;
     for (auto& message : messages) {
-      switch (message->kind) {
-      case JsonMessage::Kind::IsAlive:
-      {
+      if (message->runtime_id == IpcMessage_IsAlive::id) {
         IpcMessage_IsAlive response;
         ipc.SendToClient(0, &response); // todo: make non-blocking
         break;
       }
-      default:
-        std::cerr << "Unhandled IPC message with kind " << static_cast<int>(message->kind) << std::endl;
+      else {
+        std::cerr << "Unhandled IPC message with kind " << message->runtime_id << " (hash " << message->hashed_runtime_id << ")" << std::endl;
         exit(1);
         break;
       }
@@ -123,6 +128,37 @@ void IndexerServerMain() {
   }
 }
 
+void EmitReferences(IpcClient& ipc) {
+
+}
+
+// Separate thread whose only job is to read from stdin and
+// dispatch read commands to the actual indexer program. This
+// cannot be done on the main thread because reading from std::cin
+// blocks.
+void LanguageServerStdinToServerDispatcher(IpcClient& ipc) {
+  while (true) {
+    std::string input;
+    std::cin >> input;
+
+  }
+}
+
+// Main loop for the language server. |ipc| is connected to
+// a server.
+void LanguageServerLoop(IpcClient& ipc) {
+  while (true) {
+    std::string input;
+    std::cin >> input;
+
+    std::cout << "got input " << input << std::endl << std::endl;
+
+    if (input == "references") {
+
+    }
+  }
+}
+
 void LanguageServerMain() {
   IpcClient ipc("language_server", 0);
 
@@ -139,7 +175,7 @@ void LanguageServerMain() {
   std::vector<std::unique_ptr<BaseIpcMessage>> messages = ipc.TakeMessages();
   bool has_server = false;
   for (auto& message : messages) {
-    if (message->kind == JsonMessage::Kind::IsAlive) {
+    if (message->runtime_id == IpcMessage_IsAlive::id) {
       has_server = true;
       break;
     }
@@ -152,10 +188,131 @@ void LanguageServerMain() {
   }
 
   std::cout << "Found indexer server" << std::endl;
+  LanguageServerLoop(ipc);
+}
+
+
+
+
+
+#if false
+
+struct IpcMessage_IsAlive : public BaseIpcMessage {
+  IpcMessage_IsAlive();
+
+  // BaseIpcMessage:
+  void Serialize(Writer& writer) override;
+  void Deserialize(Reader& reader) override;
+};
+
+struct IpcMessage_ImportIndex : public BaseIpcMessage {
+  std::string path;
+
+  IpcMessage_ImportIndex();
+
+  // BaseMessage:
+  void Serialize(Writer& writer) override;
+  void Deserialize(Reader& reader) override;
+};
+
+struct IpcMessage_CreateIndex : public BaseIpcMessage {
+  std::string path;
+  std::vector<std::string> args;
+
+  IpcMessage_CreateIndex();
+
+  // BaseMessage:
+  void Serialize(Writer& writer) override;
+  void Deserialize(Reader& reader) override;
+};
+
+
+IpcMessage_IsAlive::IpcMessage_IsAlive() {
+  kind = JsonMessage::Kind::IsAlive;
+}
+
+void IpcMessage_IsAlive::Serialize(Writer& writer) {}
+
+void IpcMessage_IsAlive::Deserialize(Reader& reader) {}
+
+IpcMessage_ImportIndex::IpcMessage_ImportIndex() {
+  kind = JsonMessage::Kind::ImportIndex;
+}
+
+void IpcMessage_ImportIndex::Serialize(Writer& writer) {
+  writer.StartObject();
+  ::Serialize(writer, "path", path);
+  writer.EndObject();
+}
+void IpcMessage_ImportIndex::Deserialize(Reader& reader) {
+  ::Deserialize(reader, "path", path);
+}
+
+IpcMessage_CreateIndex::IpcMessage_CreateIndex() {
+  kind = JsonMessage::Kind::CreateIndex;
+}
+
+void IpcMessage_CreateIndex::Serialize(Writer& writer) {
+  writer.StartObject();
+  ::Serialize(writer, "path", path);
+  ::Serialize(writer, "args", args);
+  writer.EndObject();
+}
+void IpcMessage_CreateIndex::Deserialize(Reader& reader) {
+  ::Deserialize(reader, "path", path);
+  ::Deserialize(reader, "args", args);
+}
+
+// TODO: make it so we don't need an explicit list
+// of available ipc message types. Maybe use string or
+// a hash, not sure.
+
+struct IpcMessage_DocumentSymbolsRequest : public BaseIpcMessage {
+  std::string document;
+};
+
+struct IpcMessage_DocumentSymbolsResponse : public BaseIpcMessage {
+
+};
+
+
+
+
+
+
+
+struct ListSymbols : public BaseType<ListSymbols> {
+  static IpcRegistry::Id id;
+};
+
+IpcRegistry::Id ListSymbols::id = "ListSymbols";
+
+struct ListSymbol2s : public BaseType<ListSymbol2s> {
+  static IpcRegistry::Id id;
+};
+
+IpcRegistry::Id ListSymbol2s::id = "ListSymbols";
+
+#endif
+
+
+void main2() {
+  //ListSymbols l;
+  //auto& x = ListSymbols::register_;
+  //ListSymbol2s l2;
+  //auto& y = ListSymbol2s::register_;
+
+  std::cout << "main2" << std::endl;
+  std::cin.get();
 }
 
 int main(int argc, char** argv) {
-  if (argc == 1)
+  IpcMessage_IsAlive _;
+
+  //main2();
+  //return 0;
+
+  if (argc == 2)
     LanguageServerMain();
   else
     IndexerServerMain();

ipc.cc

@@ -24,40 +24,19 @@ void JsonMessage::SetPayload(size_t payload_size, const char* payload) {
   memcpy(payload_dest, payload, payload_size);
 }
 
-IpcMessage_IsAlive::IpcMessage_IsAlive() {
-  kind = JsonMessage::Kind::IsAlive;
-}
+BaseIpcMessage::BaseIpcMessage(BaseIpcMessage::DoNotDeriveDirectly) {}
 
-void IpcMessage_IsAlive::Serialize(Writer& writer) {}
+BaseIpcMessage::~BaseIpcMessage() {}
 
-void IpcMessage_IsAlive::Deserialize(Reader& reader) {}
+void BaseIpcMessage::Serialize(Writer& writer) {}
 
-IpcMessage_ImportIndex::IpcMessage_ImportIndex() {
-  kind = JsonMessage::Kind::ImportIndex;
-}
+void BaseIpcMessage::Deserialize(Reader& reader) {}
 
-void IpcMessage_ImportIndex::Serialize(Writer& writer) {
-  writer.StartObject();
-  ::Serialize(writer, "path", path);
-  writer.EndObject();
-}
-void IpcMessage_ImportIndex::Deserialize(Reader& reader) {
-  ::Deserialize(reader, "path", path);
-}
 
-IpcMessage_CreateIndex::IpcMessage_CreateIndex() {
-  kind = JsonMessage::Kind::CreateIndex;
-}
+IpcRegistry IpcRegistry::Instance;
 
-void IpcMessage_CreateIndex::Serialize(Writer& writer) {
-  writer.StartObject();
-  ::Serialize(writer, "path", path);
-  ::Serialize(writer, "args", args);
-  writer.EndObject();
-}
-void IpcMessage_CreateIndex::Deserialize(Reader& reader) {
-  ::Deserialize(reader, "path", path);
-  ::Deserialize(reader, "args", args);
+std::unique_ptr<BaseIpcMessage> IpcRegistry::Allocate(int id) {
+  return std::unique_ptr<BaseIpcMessage>((*allocators)[id]());
 }
 
 IpcDirectionalChannel::IpcDirectionalChannel(const std::string& name) {
@@ -100,12 +79,12 @@ void IpcDirectionalChannel::PushMessage(BaseIpcMessage* message) {
     if ((*shared->shared_bytes_used + sizeof(JsonMessage) + payload_size) >= shmem_size)
       continue;
 
-    get_free_message()->kind = message->kind;
+    get_free_message()->message_id = message->hashed_runtime_id;
     get_free_message()->SetPayload(payload_size, output.GetString());
 
     *shared->shared_bytes_used += sizeof(JsonMessage) + get_free_message()->payload_size;
     assert(*shared->shared_bytes_used < shmem_size);
-    get_free_message()->kind = JsonMessage::Kind::Invalid;
+    get_free_message()->message_id = -1;
     break;
   }
 
@@ -122,27 +101,14 @@ std::vector<std::unique_ptr<BaseIpcMessage>> IpcDirectionalChannel::TakeMessages
 
     memcpy(local_block, shared->shared_start, *shared->shared_bytes_used);
     *shared->shared_bytes_used = 0;
-    get_free_message()->kind = JsonMessage::Kind::Invalid;
+    get_free_message()->message_id = -1;
   }
 
   std::vector<std::unique_ptr<BaseIpcMessage>> result;
 
   char* message = local_block;
   while (remaining_bytes > 0) {
-    std::unique_ptr<BaseIpcMessage> base_message;
-    switch (as_message(message)->kind) {
-    case JsonMessage::Kind::IsAlive:
-      base_message = std::make_unique<IpcMessage_IsAlive>();
-      break;
-    case JsonMessage::Kind::CreateIndex:
-      base_message = std::make_unique<IpcMessage_CreateIndex>();
-      break;
-    case JsonMessage::Kind::ImportIndex:
-      base_message = std::make_unique<IpcMessage_ImportIndex>();
-      break;
-    default:
-      assert(false);
-    }
+    std::unique_ptr<BaseIpcMessage> base_message = IpcRegistry::Instance.Allocate(as_message(message)->message_id);
 
     rapidjson::Document document;
     document.Parse(as_message(message)->payload(), as_message(message)->payload_size);

ipc.h

@@ -4,6 +4,7 @@
 #include <chrono>
 #include <string>
 #include <thread>
+#include <unordered_map>
 
 #include <rapidjson/document.h>
 #include <rapidjson/prettywriter.h>
@@ -21,57 +22,99 @@ using Reader = rapidjson::Document;
 // completely different address.
 
 struct JsonMessage {
-  enum class Kind {
-    Invalid,
-    IsAlive,
-    CreateIndex,
-    ImportIndex,
-  };
-
-  Kind kind;
+  int message_id;
   size_t payload_size;
 
   const char* payload();
   void SetPayload(size_t payload_size, const char* payload);
 };
 
+using IpcMessageId = std::string;
+
 struct BaseIpcMessage {
-  JsonMessage::Kind kind;
-  virtual ~BaseIpcMessage() {}
+  virtual ~BaseIpcMessage();
 
-  virtual void Serialize(Writer& writer) = 0;
-  virtual void Deserialize(Reader& reader) = 0;
+  virtual void Serialize(Writer& writer);
+  virtual void Deserialize(Reader& reader);
+
+  IpcMessageId runtime_id;
+  int hashed_runtime_id;
+
+  /*
+private:
+  template<typename T>
+  friend struct IpcMessage;
+  */
+
+  enum class DoNotDeriveDirectly {
+    DeriveFromIpcMessageInstead
+  };
+  BaseIpcMessage(DoNotDeriveDirectly);
 };
 
-struct IpcMessage_IsAlive : public BaseIpcMessage {
-  IpcMessage_IsAlive();
+struct IpcRegistry {
+  using Allocator = std::function<BaseIpcMessage*()>;
 
-  // BaseIpcMessage:
-  void Serialize(Writer& writer) override;
-  void Deserialize(Reader& reader) override;
+  // Use unique_ptrs so we can initialize on first use
+  // (static init order might not be right).
+  std::unique_ptr<std::unordered_map<int, Allocator>> allocators;
+  std::unique_ptr<std::unordered_map<int, std::string>> hash_to_id;
+
+  template<typename T>
+  int RegisterAllocator();
+
+  std::unique_ptr<BaseIpcMessage> Allocate(int id);
+
+  static IpcRegistry* instance() {
+    // TODO: Remove static magic. Just call register explicitly.
+    return instance_;
+  }
+  static IpcRegistry* instance_;
 };
 
-struct IpcMessage_ImportIndex : public BaseIpcMessage {
-  std::string path;
+template<typename T>
+int IpcRegistry::RegisterAllocator() {
+  if (!allocators) {
+    allocators = std::make_unique<std::unordered_map<int, Allocator>>();
+    hash_to_id = std::make_unique<std::unordered_map<int, std::string>>();
+  }
 
-  IpcMessage_ImportIndex();
+  IpcMessageId id = T::id;
 
-  // BaseMessage:
-  void Serialize(Writer& writer) override;
-  void Deserialize(Reader& reader) override;
+  int hash = std::hash<IpcMessageId>()(id);
+  auto it = allocators->find(hash);
+  assert(allocators->find(hash) == allocators->end() && "There is already an IPC message with the given id");
+
+  (*hash_to_id)[hash] = id;
+  (*allocators)[hash] = []() {
+    return new T();
   };
 
-struct IpcMessage_CreateIndex : public BaseIpcMessage {
-  std::string path;
-  std::vector<std::string> args;
+  return hash;
+}
 
-  IpcMessage_CreateIndex();
+template<typename TChild>
+struct IpcMessage : public BaseIpcMessage {
+  IpcMessage();
 
-  // BaseMessage:
-  void Serialize(Writer& writer) override;
-  void Deserialize(Reader& reader) override;
+  static int hashed_id_;
 };
 
+template<typename TChild>
+int IpcMessage<TChild>::hashed_id_ = IpcRegistry::Instance.RegisterAllocator<TChild>();
+
+template<typename TChild>
+IpcMessage<TChild>::IpcMessage()
+  : BaseIpcMessage(DoNotDeriveDirectly::DeriveFromIpcMessageInstead) {
+  runtime_id = TChild::id;
+  hashed_runtime_id = hashed_id_;
+}
+
+
+
+
+
+
 struct IpcDirectionalChannel {
   // NOTE: We keep all pointers in terms of char* so pointer arithmetic is
   // always relative to bytes.