strip Channel from all class names

[folly.git] / folly / wangle / channel / Handler.h

diff --git a/folly/wangle/channel/Handler.h b/folly/wangle/channel/Handler.h
new file mode 100644 (file)
index 0000000..67219f1
--- /dev/null
+++ b/folly/wangle/channel/Handler.h
@@ -0,0 +1,196 @@
+/*
+ * Copyright 2015 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <folly/futures/Future.h>
+#include <folly/wangle/channel/Pipeline.h>
+#include <folly/io/IOBuf.h>
+#include <folly/io/IOBufQueue.h>
+
+namespace folly { namespace wangle {
+
+template <class Rin, class Rout = Rin, class Win = Rout, class Wout = Rin>
+class Handler {
+ public:
+  typedef Rin rin;
+  typedef Rout rout;
+  typedef Win win;
+  typedef Wout wout;
+  typedef HandlerContext<Rout, Wout> Context;
+  virtual ~Handler() {}
+
+  virtual void read(Context* ctx, Rin msg) = 0;
+  virtual void readEOF(Context* ctx) {
+    ctx->fireReadEOF();
+  }
+  virtual void readException(Context* ctx, exception_wrapper e) {
+    ctx->fireReadException(std::move(e));
+  }
+
+  virtual Future<void> write(Context* ctx, Win msg) = 0;
+  virtual Future<void> close(Context* ctx) {
+    return ctx->fireClose();
+  }
+
+  virtual void attachPipeline(Context* ctx) {}
+  virtual void attachTransport(Context* ctx) {}
+
+  virtual void detachPipeline(Context* ctx) {}
+  virtual void detachTransport(Context* ctx) {}
+
+  /*
+  // Other sorts of things we might want, all shamelessly stolen from Netty
+  // inbound
+  virtual void exceptionCaught(
+      HandlerContext* ctx,
+      exception_wrapper e) {}
+  virtual void channelRegistered(HandlerContext* ctx) {}
+  virtual void channelUnregistered(HandlerContext* ctx) {}
+  virtual void channelActive(HandlerContext* ctx) {}
+  virtual void channelInactive(HandlerContext* ctx) {}
+  virtual void channelReadComplete(HandlerContext* ctx) {}
+  virtual void userEventTriggered(HandlerContext* ctx, void* evt) {}
+  virtual void channelWritabilityChanged(HandlerContext* ctx) {}
+
+  // outbound
+  virtual Future<void> bind(
+      HandlerContext* ctx,
+      SocketAddress localAddress) {}
+  virtual Future<void> connect(
+          HandlerContext* ctx,
+          SocketAddress remoteAddress, SocketAddress localAddress) {}
+  virtual Future<void> disconnect(HandlerContext* ctx) {}
+  virtual Future<void> deregister(HandlerContext* ctx) {}
+  virtual Future<void> read(HandlerContext* ctx) {}
+  virtual void flush(HandlerContext* ctx) {}
+  */
+};
+
+template <class R, class W = R>
+class HandlerAdapter : public Handler<R, R, W, W> {
+ public:
+  typedef typename Handler<R, R, W, W>::Context Context;
+
+  void read(Context* ctx, R msg) override {
+    ctx->fireRead(std::forward<R>(msg));
+  }
+
+  Future<void> write(Context* ctx, W msg) override {
+    return ctx->fireWrite(std::forward<W>(msg));
+  }
+};
+
+typedef HandlerAdapter<IOBufQueue&, std::unique_ptr<IOBuf>>
+BytesToBytesHandler;
+
+template <class HandlerT, bool Shared = true>
+class HandlerPtr : public Handler<
+                            typename HandlerT::rin,
+                            typename HandlerT::rout,
+                            typename HandlerT::win,
+                            typename HandlerT::wout> {
+ public:
+  typedef typename std::conditional<
+    Shared,
+    std::shared_ptr<HandlerT>,
+    HandlerT*>::type
+  Ptr;
+
+  typedef typename HandlerT::Context Context;
+
+  explicit HandlerPtr(Ptr handler)
+    : handler_(std::move(handler)) {}
+
+  Ptr getHandler() {
+    return handler_;
+  }
+
+  void setHandler(Ptr handler) {
+    if (handler == handler_) {
+      return;
+    }
+    if (handler_ && ctx_) {
+      handler_->detachPipeline(ctx_);
+    }
+    handler_ = std::move(handler);
+    if (handler_ && ctx_) {
+      handler_->attachPipeline(ctx_);
+      if (ctx_->getTransport()) {
+        handler_->attachTransport(ctx_);
+      }
+    }
+  }
+
+  void attachPipeline(Context* ctx) override {
+    ctx_ = ctx;
+    if (handler_) {
+      handler_->attachPipeline(ctx_);
+    }
+  }
+
+  void attachTransport(Context* ctx) override {
+    ctx_ = ctx;
+    if (handler_) {
+      handler_->attachTransport(ctx_);
+    }
+  }
+
+  void detachPipeline(Context* ctx) override {
+    ctx_ = ctx;
+    if (handler_) {
+      handler_->detachPipeline(ctx_);
+    }
+  }
+
+  void detachTransport(Context* ctx) override {
+    ctx_ = ctx;
+    if (handler_) {
+      handler_->detachTransport(ctx_);
+    }
+  }
+
+  void read(Context* ctx, typename HandlerT::rin msg) override {
+    DCHECK(handler_);
+    handler_->read(ctx, std::forward<typename HandlerT::rin>(msg));
+  }
+
+  void readEOF(Context* ctx) override {
+    DCHECK(handler_);
+    handler_->readEOF(ctx);
+  }
+
+  void readException(Context* ctx, exception_wrapper e) override {
+    DCHECK(handler_);
+    handler_->readException(ctx, std::move(e));
+  }
+
+  Future<void> write(Context* ctx, typename HandlerT::win msg) override {
+    DCHECK(handler_);
+    return handler_->write(ctx, std::forward<typename HandlerT::win>(msg));
+  }
+
+  Future<void> close(Context* ctx) override {
+    DCHECK(handler_);
+    return handler_->close(ctx);
+  }
+
+ private:
+  Context* ctx_;
+  Ptr handler_;
+};
+
+}}