blob: 77fa9220db760408706bf815a80fc532dd12b81e [file] [log] [blame]
// Copyright 2022 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
//go:build ignore
// This program runs another program provided on standard input,
// prints its standard output, then terminates. It logs to stderr.
//
// It first reads all of standard input, then splits it into words on
// whitespace. It treats the first word as the program path and the rest as
// arguments.
package main
import (
"bytes"
"encoding/json"
"errors"
"io"
"log"
"os"
"os/exec"
)
func main() {
log.SetOutput(os.Stderr)
log.SetPrefix("runner: ")
log.Print("starting")
in, err := io.ReadAll(os.Stdin)
if err != nil {
log.Fatal(err)
}
log.Printf("read %q", in)
var cmd exec.Cmd
if err := json.Unmarshal(in, &cmd); err != nil {
log.Fatal(err)
}
log.Printf("cmd: %+v", cmd)
out, err := cmd.Output()
if err != nil {
s := err.Error()
var eerr *exec.ExitError
if errors.As(err, &eerr) {
s += ": " + string(bytes.TrimSpace(eerr.Stderr))
}
log.Fatalf("%v failed with %s", cmd.Args, s)
}
if _, err := os.Stdout.Write(out); err != nil {
log.Fatal(err)
}
log.Print("succeeded")
}