| /* |
| * Copyright 2015, The Android Open Source Project |
| * |
| * 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. |
| */ |
| |
| package rpc |
| |
| import ( |
| "bufio" |
| "io" |
| |
| "android.googlesource.com/platform/tools/gpu/binary" |
| "android.googlesource.com/platform/tools/gpu/log" |
| "android.googlesource.com/platform/tools/gpu/multiplexer" |
| ) |
| |
| // Handler is the signature for a function that handles incoming rpc calls. |
| type Handler func(interface{}) binary.Encodable |
| |
| // Server implements the receiving side of a client server rpc pair. |
| // It listens on the reader for calls, and dispatches them to the supplied handler. |
| // Any result returned from the handler is then sent back down the writer. |
| func Serve(logger log.Logger, r io.Reader, w io.Writer, mtu int, handler Handler) { |
| multiplexer.New(r, w, mtu, func(channel io.ReadWriteCloser) { |
| // If Close fails, multiplexer already knows, so we ignore the error |
| defer channel.Close() |
| |
| w := bufio.NewWriterSize(channel, mtu) |
| // Flush only fails if channel fails, multiplexer already knows, so we ignore the error |
| defer w.Flush() |
| |
| d := binary.NewDecoder(channel) |
| e := binary.NewEncoder(w) |
| |
| // Check the RPC header |
| if val, err := d.Uint32(); val != header || err != nil { |
| logger.Error("%v", ErrInvalidHeader) |
| e.Object(ErrInvalidHeader) |
| return |
| } |
| |
| // Decode the call |
| val, err := d.Object() |
| if err != nil { |
| logger.Error("Error decoding call: %v", err) |
| e.Object(NewError("Failed to decode call. Reason: %v", err)) |
| return |
| } |
| |
| // Invoke the call |
| res := handler(val) |
| |
| // Encode the call result |
| if err := e.Object(res); err != nil { |
| logger.Error("Error encoding result for %T: %v", val, err) |
| e.Object(NewError("Failed to encode call result. Reason: %v", err)) |
| return |
| } |
| }) |
| } |