[clangd] Initial cancellation mechanism for LSP requests.

Reviewers: ilya-biryukov, ioeric, hokein

Reviewed By: ilya-biryukov

Subscribers: mgorny, ioeric, MaskRay, jkorous, arphaman, jfb, cfe-commits

Differential Revision: https://reviews.llvm.org/D50502

llvm-svn: 340607

1 files changed, 14 insertions, 0 deletions

diff --git a/clang-tools-extra/clangd/Protocol.h b/clang-tools-extra/clangd/Protocol.h
index fc6a3a8c9f1..d019e82dbf7 100644
--- a/clang-tools-extra/clangd/Protocol.h
+++ b/clang-tools-extra/clangd/Protocol.h
@@ -871,6 +871,20 @@ struct DocumentHighlight {
 llvm::json::Value toJSON(const DocumentHighlight &DH);
 llvm::raw_ostream &operator<<(llvm::raw_ostream &, const DocumentHighlight &);
 
+struct CancelParams {
+  /// The request id to cancel.
+  /// This can be either a number or string, if it is a number simply print it
+  /// out and always use a string.
+  std::string ID;
+};
+llvm::json::Value toJSON(const CancelParams &);
+llvm::raw_ostream &operator<<(llvm::raw_ostream &, const CancelParams &);
+bool fromJSON(const llvm::json::Value &, CancelParams &);
+
+/// Param can be either of type string or number. Returns the result as a
+/// string.
+llvm::Optional<std::string> parseNumberOrString(const llvm::json::Value *Param);
+
 } // namespace clangd
 } // namespace clang