[Lldb-commits] [lldb] [lldb-dap] Adding support for cancelling a request. (PR #130169)

[Jonas Devlieghere via lldb-commits]

================
@@ -777,28 +798,134 @@ llvm::Error DAP::Disconnect(bool terminateDebuggee) {
   return ToError(error);
 }
 
+template <typename T>
+static std::optional<T> getArgumentsIfRequest(const protocol::Message &pm,
+                                              llvm::StringLiteral command) {
+  auto *const req = std::get_if<protocol::Request>(&pm);
+  if (!req || req->command != command)
+    return std::nullopt;
+
+  T args;
+  llvm::json::Path::Root root;
+  if (!fromJSON(req->arguments, args, root)) {
+    return std::nullopt;
+  }
+
+  return std::move(args);
+}
+
 llvm::Error DAP::Loop() {
-  auto cleanup = llvm::make_scope_exit([this]() {
+  std::deque<protocol::Message> queue;
+  std::condition_variable queue_cv;
+  std::mutex queue_mutex;
+  std::future<llvm::Error> queue_reader = std::async([&]() -> llvm::Error {
+    llvm::set_thread_name(transport.GetClientName() + ".transport_handler");
+    auto cleanup = llvm::make_scope_exit([&]() {
+      // Ensure we're marked as disconnecting when the reader exits.
+      disconnecting = true;
+      queue_cv.notify_all();
+    });
+
+    while (!disconnecting) {
+      llvm::Expected<std::optional<protocol::Message>> next =
+          transport.Read(std::chrono::seconds(1));
+      bool timeout = false;
+      if (llvm::Error Err = llvm::handleErrors(
+              next.takeError(),
+              [&](std::unique_ptr<llvm::StringError> Err) -> llvm::Error {
----------------
JDevlieghere wrote:

Do we only want to handle StringError?
```suggestion
              [&](std::unique_ptr<llvm::Error> Err) -> llvm::Error {
```

https://github.com/llvm/llvm-project/pull/130169