Added marshalling to main thread messages sent from native side (#422)

* Added marshalling to main thread messages sent from native side --------- Co-authored-by: Anton Sakhon <asakhon@universe.dart.spb@asakhon2.nb.ipa.dataart.net>

Author: Kofhein

AUTHORS

@@ -16,3 +16,4 @@ Stanislav Shmarov <github@snarpix.com>
 Sebastian Urban <surban@surban.net>
 Ómar Högni Guðmarsson <ohg@skaginn3x.com>
 Athaariq Ardhiansyah <foss@athaariq.my.id>
+Anton Sakhon <kofhein@gmail.com>

src/flutter/shell/platform/common/client_wrapper/core_implementations.cc

@@ -66,6 +66,11 @@ BinaryMessengerImpl::BinaryMessengerImpl(
 
 BinaryMessengerImpl::~BinaryMessengerImpl() = default;
 
+void CaptureCleaner(void* lambda) {
+ auto& cleanup = *reinterpret_cast<std::function<void()>*>(lambda);
+ cleanup();
+}
+
 void BinaryMessengerImpl::Send(const std::string& channel,
  const uint8_t* message,
  size_t message_size,
@@ -89,10 +94,10 @@ void BinaryMessengerImpl::Send(const std::string& channel,
  };
  bool result = FlutterDesktopMessengerSendWithReply(
  messenger_, channel.c_str(), message, message_size, message_reply,
- captures);
- if (!result) {
- delete captures;
- }
+ captures, [](void* captures_data) {
+  auto captures = reinterpret_cast<Captures*>(captures_data);
+  delete captures;
+  });
 }
 
 void BinaryMessengerImpl::SetMessageHandler(const std::string& channel,

src/flutter/shell/platform/common/public/flutter_messenger.h

@@ -63,7 +63,8 @@ FLUTTER_EXPORT bool FlutterDesktopMessengerSendWithReply(
  const uint8_t* message,
  const size_t message_size,
  const FlutterDesktopBinaryReply reply,
- void* user_data);
+ void* user_data,
+ void (*cleanup)(void* captures_data));
 
 // Sends a reply to a FlutterDesktopMessage for the given response handle.
 //

src/flutter/shell/platform/linux_embedded/flutter_elinux.cc

@@ -199,22 +199,36 @@ void FlutterDesktopPluginRegistrarSetDestructionHandler(
  registrar->engine->SetPluginRegistrarDestructionCallback(callback);
 }
 
-bool FlutterDesktopMessengerSendWithReply(FlutterDesktopMessengerRef messenger,
- const char* channel,
- const uint8_t* message,
- const size_t message_size,
- const FlutterDesktopBinaryReply reply,
- void* user_data) {
- return messenger->GetEngine()->SendPlatformMessage(
- channel, message, message_size, reply, user_data);
+bool FlutterDesktopMessengerSendWithReply(
+ FlutterDesktopMessengerRef messenger,
+ const char* channel,
+ const uint8_t* message,
+ const size_t message_size,
+ const FlutterDesktopBinaryReply reply,
+ void* user_data,
+ void (*cleanup)(void* captures_data)) {
+ // As we pass data to lambda and it's pointers we need to make sure that we
+ // send valid data
+ std::string channel_copy(channel);
+ std::vector<uint8_t> message_copy(message, message + message_size);
+
+ messenger->GetEngine()->task_runner()->PostTask([=]() {
+ if (!messenger->GetEngine()->SendPlatformMessage(
+ channel_copy.c_str(), message_copy.data(), message_copy.size(),
+ reply, user_data) &&
+ user_data) {
+ cleanup(user_data);
+ }
+ });
+ return true;
 }
 
 bool FlutterDesktopMessengerSend(FlutterDesktopMessengerRef messenger,
  const char* channel,
  const uint8_t* message,
  const size_t message_size) {
- return FlutterDesktopMessengerSendWithReply(messenger, channel, message,
-  message_size, nullptr, nullptr);
+ return FlutterDesktopMessengerSendWithReply(
+ messenger, channel, message, message_size, nullptr, nullptr, nullptr);
 }
 
 void FlutterDesktopMessengerSendResponse(