remove prefixed io

The main process is now handling what output to print, so it doesn't do
any good to try and run it through prefixedio, which is only adding
extra coordination to echo the same data.

go.mod

@@ -84,7 +84,7 @@ require (
 	github.com/lusis/go-artifactory v0.0.0-20160115162124-7e4ce345df82
 	github.com/masterzen/simplexml v0.0.0-20190410153822-31eea3082786 // indirect
 	github.com/masterzen/winrm v0.0.0-20200615185753-c42b5136ff88
-	github.com/mattn/go-colorable v0.1.8
+	github.com/mattn/go-colorable v0.1.8 // indirect
 	github.com/mattn/go-isatty v0.0.12
 	github.com/mattn/go-shellwords v1.0.4
 	github.com/miekg/dns v1.0.8 // indirect
@@ -97,7 +97,6 @@ require (
 	github.com/mitchellh/gox v1.0.1
 	github.com/mitchellh/mapstructure v1.1.2
 	github.com/mitchellh/panicwrap v1.0.0
-	github.com/mitchellh/prefixedio v0.0.0-20190213213902-5733675afd51
 	github.com/mitchellh/reflectwalk v1.0.1
 	github.com/nu7hatch/gouuid v0.0.0-20131221200532-179d4d0c4d8d // indirect
 	github.com/packer-community/winrmcp v0.0.0-20180921211025-c76d91c1e7db

go.sum

@@ -246,8 +246,6 @@ github.com/hashicorp/go-msgpack v0.5.4 h1:SFT72YqIkOcLdWJUYcriVX7hbrZpwc/f7h8aW2
 github.com/hashicorp/go-msgpack v0.5.4/go.mod h1:ahLV/dePpqEmjfWmKiqvPkv/twdG7iPBM1vqhUKIvfM=
 github.com/hashicorp/go-multierror v1.0.0 h1:iVjPR7a6H0tWELX5NxNe7bYopibicUzc7uPribsnS6o=
 github.com/hashicorp/go-multierror v1.0.0/go.mod h1:dHtQlpGsu+cZNNAkkCN/P3hoUDHhCYQXV3UM06sGGrk=
-github.com/hashicorp/go-plugin v1.3.0 h1:4d/wJojzvHV1I4i/rrjVaeuyxWrLzDE1mDCyDy8fXS8=
-github.com/hashicorp/go-plugin v1.3.0/go.mod h1:F9eH4LrE/ZsRdbwhfjs9k9HoDUwAHnYtXdgmf1AVNs0=
 github.com/hashicorp/go-retryablehttp v0.5.2 h1:AoISa4P4IsW0/m4T6St8Yw38gTl5GtBAgfkhYh1xAz4=
 github.com/hashicorp/go-retryablehttp v0.5.2/go.mod h1:9B5zBasrRhHXnJnui7y6sL7es7NDiJgTc6Er0maI1Xs=
 github.com/hashicorp/go-rootcerts v1.0.0 h1:Rqb66Oo1X/eSV1x66xbDccZjhJigjg0+e82kpwzSwCI=
@@ -384,8 +382,6 @@ github.com/mitchellh/mapstructure v1.1.2 h1:fmNYVwqnSfB9mZU6OS2O6GsXM+wcskZDuKQz
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/mitchellh/panicwrap v1.0.0 h1:67zIyVakCIvcs69A0FGfZjBdPleaonSgGlXRSRlb6fE=
 github.com/mitchellh/panicwrap v1.0.0/go.mod h1:pKvZHwWrZowLUzftuFq7coarnxbBXU4aQh3N0BJOeeA=
-github.com/mitchellh/prefixedio v0.0.0-20190213213902-5733675afd51 h1:eD92Am0Qf3rqhsOeA1zwBHSfRkoHrt4o6uORamdmJP8=
-github.com/mitchellh/prefixedio v0.0.0-20190213213902-5733675afd51/go.mod h1:kB1naBgV9ORnkiTVeyJOI1DavaJkG4oNIq0Af6ZVKUo=
 github.com/mitchellh/reflectwalk v1.0.0 h1:9D+8oIskB4VJBN5SFlmc27fSlIBZaov1Wpk/IfikLNY=
 github.com/mitchellh/reflectwalk v1.0.0/go.mod h1:mSTlrgnPZtwu0c4WaC2kGObEpuNDbx0jmZXqmk4esnw=
 github.com/mitchellh/reflectwalk v1.0.1 h1:FVzMWA5RllMAKIdUSC8mdWo3XtwoecrH79BY70sEEpE=

main.go

@@ -3,7 +3,6 @@ package main
 import (
 	"encoding/json"
 	"fmt"
-	"io"
 	"io/ioutil"
 	"log"
 	"net"
@@ -11,7 +10,6 @@ import (
 	"path/filepath"
 	"runtime"
 	"strings"
-	"sync"
 
 	"github.com/hashicorp/go-plugin"
 	"github.com/hashicorp/terraform-svchost/disco"
@@ -21,12 +19,10 @@ import (
 	"github.com/hashicorp/terraform/httpclient"
 	"github.com/hashicorp/terraform/internal/logging"
 	"github.com/hashicorp/terraform/version"
-	"github.com/mattn/go-colorable"
 	"github.com/mattn/go-shellwords"
 	"github.com/mitchellh/cli"
 	"github.com/mitchellh/colorstring"
 	"github.com/mitchellh/panicwrap"
-	"github.com/mitchellh/prefixedio"
 
 	backendInit "github.com/hashicorp/terraform/backend/init"
 )
@@ -59,15 +55,8 @@ func realMain() int {
 		defer os.Remove(logTempFile.Name())
 		defer logTempFile.Close()
 
-		// Setup the prefixed readers that send data properly to
-		// stdout/stderr.
-		doneCh := make(chan struct{})
-		outR, outW := io.Pipe()
-		go copyOutput(outR, doneCh)
-
 		// Create the configuration for panicwrap and wrap our executable
 		wrapConfig.Handler = logging.PanicHandler(logTempFile)
-		wrapConfig.Stdout = outW
 		wrapConfig.IgnoreSignals = ignoreSignals
 		wrapConfig.ForwardSignals = forwardSignals
 		exitStatus, err := panicwrap.Wrap(&wrapConfig)
@@ -76,20 +65,7 @@ func realMain() int {
 			return 1
 		}
 
-		// If >= 0, we're the parent, so just exit
+		return exitStatus
-		if exitStatus >= 0 {
-			// Close the stdout writer so that our copy process can finish
-			outW.Close()
-
-			// Wait for the output copying to finish
-			<-doneCh
-
-			return exitStatus
-		}
-
-		// We're the child, so just close the tempfile we made in order to
-		// save file handles since the tempfile is only used by the parent.
-		logTempFile.Close()
 	}
 
 	// Call the real main
@@ -97,15 +73,10 @@ func realMain() int {
 }
 
 func init() {
-	Ui = &cli.PrefixedUi{
+	Ui = &cli.BasicUi{
-		AskPrefix:    OutputPrefix,
+		Writer:      os.Stdout,
-		OutputPrefix: OutputPrefix,
+		ErrorWriter: os.Stderr,
-		InfoPrefix:   OutputPrefix,
+		Reader:      os.Stdin,
-		ErrorPrefix:  ErrorPrefix,
-		Ui: &cli.BasicUi{
-			Writer: os.Stdout,
-			Reader: os.Stdin,
-		},
 	}
 }
 
@@ -299,65 +270,6 @@ func wrappedMain() int {
 	return exitCode
 }
 
-// copyOutput uses output prefixes to determine whether data on stdout
-// should go to stdout or stderr. This is due to panicwrap using stderr
-// as the log and error channel.
-func copyOutput(r io.Reader, doneCh chan<- struct{}) {
-	defer close(doneCh)
-
-	pr, err := prefixedio.NewReader(r)
-	if err != nil {
-		panic(err)
-	}
-
-	stderrR, err := pr.Prefix(ErrorPrefix)
-	if err != nil {
-		panic(err)
-	}
-	stdoutR, err := pr.Prefix(OutputPrefix)
-	if err != nil {
-		panic(err)
-	}
-	defaultR, err := pr.Prefix("")
-	if err != nil {
-		panic(err)
-	}
-
-	var stdout io.Writer = os.Stdout
-	var stderr io.Writer = os.Stderr
-
-	if runtime.GOOS == "windows" {
-		stdout = colorable.NewColorableStdout()
-		stderr = colorable.NewColorableStderr()
-
-		// colorable is not concurrency-safe when stdout and stderr are the
-		// same console, so we need to add some synchronization to ensure that
-		// we can't be concurrently writing to both stderr and stdout at
-		// once, or else we get intermingled writes that create gibberish
-		// in the console.
-		wrapped := synchronizedWriters(stdout, stderr)
-		stdout = wrapped[0]
-		stderr = wrapped[1]
-	}
-
-	var wg sync.WaitGroup
-	wg.Add(3)
-	go func() {
-		defer wg.Done()
-		io.Copy(stderr, stderrR)
-	}()
-	go func() {
-		defer wg.Done()
-		io.Copy(stdout, stdoutR)
-	}()
-	go func() {
-		defer wg.Done()
-		io.Copy(stdout, defaultR)
-	}()
-
-	wg.Wait()
-}
-
 func mergeEnvArgs(envName string, cmd string, args []string) ([]string, error) {
 	v := os.Getenv(envName)
 	if v == "" {