|  | // Copyright 2020 The Monogon Project Authors. | 
|  | // | 
|  | // SPDX-License-Identifier: Apache-2.0 | 
|  | // | 
|  | // 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 main | 
|  |  | 
|  | import ( | 
|  | "fmt" | 
|  | "io" | 
|  | "log" | 
|  | "os" | 
|  |  | 
|  | "source.monogon.dev/metropolis/pkg/logbuffer" | 
|  | ) | 
|  |  | 
|  | // prefixedStdout is a os.Stdout proxy that prefixes every line with a constant | 
|  | // prefix. This is used to show logs from two Metropolis nodes without getting | 
|  | // them confused. | 
|  | // TODO(q3k): move to logging API instead of relying on qemu stdout, and remove | 
|  | // this function. | 
|  | func prefixedStdout(prefix string) io.ReadWriter { | 
|  | lb := logbuffer.NewLineBuffer(2048, func(l *logbuffer.Line) { | 
|  | fmt.Fprintf(os.Stdout, "%s%s\n", prefix, l.Data) | 
|  | }) | 
|  | // Make a ReaderWriter from LineBuffer (a Reader), by combining into an | 
|  | // anonymous struct with a io.MultiReader() (which will always return EOF | 
|  | // on every Read if given no underlying readers). | 
|  | return struct { | 
|  | io.Reader | 
|  | io.Writer | 
|  | }{ | 
|  | Reader: io.MultiReader(), | 
|  | Writer: lb, | 
|  | } | 
|  | } | 
|  |  | 
|  | func main() { | 
|  | log.Fatal("unimplemented") | 
|  | } |