[Lldb-commits] [lldb] [lldb] Move Transport class into lldb_private (NFC) (PR #143806)

[John Harrison via lldb-commits]

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@@ -0,0 +1,131 @@
+//===-- JSONTransport.h ---------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Transport layer for encoding and decoding JSON protocol messages.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLDB_HOST_JSONTRANSPORT_H
+#define LLDB_HOST_JSONTRANSPORT_H
+
+#include "lldb/lldb-forward.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/FormatVariadic.h"
+#include "llvm/Support/JSON.h"
+#include <chrono>
+#include <system_error>
+
+namespace lldb_private {
+
+class TransportEOFError : public llvm::ErrorInfo<TransportEOFError> {
+public:
+  static char ID;
+
+  TransportEOFError() = default;
+
+  void log(llvm::raw_ostream &OS) const override {
+    OS << "transport end of file reached";
+  }
+  std::error_code convertToErrorCode() const override {
+    return llvm::inconvertibleErrorCode();
+  }
+};
+
+class TransportTimeoutError : public llvm::ErrorInfo<TransportTimeoutError> {
+public:
+  static char ID;
+
+  TransportTimeoutError() = default;
+
+  void log(llvm::raw_ostream &OS) const override {
+    OS << "transport operation timed out";
+  }
+  std::error_code convertToErrorCode() const override {
+    return std::make_error_code(std::errc::timed_out);
+  }
+};
+
+class TransportClosedError : public llvm::ErrorInfo<TransportClosedError> {
+public:
+  static char ID;
+
+  TransportClosedError() = default;
+
+  void log(llvm::raw_ostream &OS) const override {
+    OS << "transport is closed";
+  }
+  std::error_code convertToErrorCode() const override {
+    return llvm::inconvertibleErrorCode();
+  }
+};
+
+/// A transport class that uses JSON for communication.
+class JSONTransport {
+public:
+  JSONTransport(llvm::StringRef client_name, lldb::IOObjectSP input,
+                lldb::IOObjectSP output);
+  virtual ~JSONTransport() = default;
+
+  /// Transport is not copyable.
+  /// @{
+  JSONTransport(const JSONTransport &rhs) = delete;
+  void operator=(const JSONTransport &rhs) = delete;
+  /// @}
+
+  /// Writes a message to the output stream.
+  template <typename T> llvm::Error Write(const T &t) {
+    const std::string message = llvm::formatv("{0}", toJSON(t)).str();
+    return WriteImpl(message);
+  }
+
+  /// Reads the next message from the input stream.
+  template <typename T>
+  llvm::Expected<T> Read(const std::chrono::microseconds &timeout) {
+    llvm::Expected<std::string> message = ReadImpl(timeout);
+    if (!message)
+      return message.takeError();
+    return llvm::json::parse<T>(/*JSON=*/*message,
+                                /*RootName=*/"transport_message");
----------------
ashgti wrote:

Seems reasonable, we can always add it later if we want it for error reporting.

https://github.com/llvm/llvm-project/pull/143806