util.go

//
// 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 oci2aci

import (
	"fmt"
	"io"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"strings"
)

var debugEnabled bool

type Err struct {
	Message string
	File    string
	Path    string
	Func    string
	Line    int
}

func (e *Err) Error() string {
	return fmt.Sprintf("[%v:%v] %v", e.File, e.Line, e.Message)
}

func printTo(w io.Writer, i ...interface{}) {
	s := fmt.Sprint(i...)
	fmt.Fprintln(w, strings.TrimSuffix(s, "\n"))
}

func Warn(i ...interface{}) {
	printTo(os.Stderr, i...)
}

func Info(i ...interface{}) {
	printTo(os.Stderr, i...)
}

func Debug(i ...interface{}) {
	if debugEnabled {
		printTo(os.Stderr, i...)
	}
}

func InitDebug() {
	debugEnabled = true
}

func run(cmd *exec.Cmd) error {
	/*if debugEnabled {
		log.Printf("run: %v %v", cmd.Path, cmd.Args)
	}*/
	stdout, err := cmd.StdoutPipe()
	if err != nil {
		return errorf(err.Error())
	}
	stderr, err := cmd.StderrPipe()
	if err != nil {
		return errorf(err.Error())
	}
	go io.Copy(os.Stdout, stdout)
	go io.Copy(os.Stderr, stderr)
	return cmd.Run()
}

func errorf(format string, args ...interface{}) error {
	msg := fmt.Sprintf(format, args...)
	pc, filePath, lineNo, ok := runtime.Caller(1)
	if !ok {
		return &Err{
			Message: msg,
			File:    "unknown_file",
			Path:    "unknown_path",
			Func:    "unknown_func",
			Line:    0,
		}
	}
	return &Err{
		Message: msg,
		File:    filepath.Base(filePath),
		Path:    filePath,
		Func:    runtime.FuncForPC(pc).Name(),
		Line:    lineNo,
	}
}