src: implement debug output utilities

Implement utilities for easier debugging of Node.js core code,
inspired by the HTTP/2 debugging code. Debugging is, however,
implemented at runtime rather than at compile time, controlled
through a new `NODE_DEBUG_NATIVE=categories` environment variable.

The runtime overhead in the debugging-disabled case amounts to
1 well-cachable one-byte read per debug call.

PR-URL: https://github.com/nodejs/node/pull/20987
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Minwoo Jung <minwoo@nodesource.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/async_wrap.h b/src/async_wrap.h
index 17017ab602..451bcfe12e 100644
--- a/src/async_wrap.h
+++ b/src/async_wrap.h
@@ -167,6 +167,7 @@ class AsyncWrap : public BaseObject {
                                                 v8::Local<v8::Value>* argv);
 
   virtual size_t self_size() const = 0;
+  virtual std::string diagnostic_name() const;
 
   static void WeakCallback(const v8::WeakCallbackInfo<DestroyParam> &info);