syncthing/cmd/syncthing/usage.go

67 lines
1.6 KiB
Go

// Copyright (C) 2014 The Syncthing Authors.
//
// This program is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the Free
// Software Foundation, either version 3 of the License, or (at your option)
// any later version.
//
// This program is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
// more details.
//
// You should have received a copy of the GNU General Public License along
// with this program. If not, see <http://www.gnu.org/licenses/>.
package main
import (
"bytes"
"flag"
"fmt"
"io"
"text/tabwriter"
)
func optionTable(w io.Writer, rows [][]string) {
tw := tabwriter.NewWriter(w, 2, 4, 2, ' ', 0)
for _, row := range rows {
for i, cell := range row {
if i > 0 {
tw.Write([]byte("\t"))
}
tw.Write([]byte(cell))
}
tw.Write([]byte("\n"))
}
tw.Flush()
}
func usageFor(fs *flag.FlagSet, usage string, extra string) func() {
return func() {
var b bytes.Buffer
b.WriteString("Usage:\n " + usage + "\n")
var options [][]string
fs.VisitAll(func(f *flag.Flag) {
var opt = " -" + f.Name
if f.DefValue != "false" {
opt += "=" + fmt.Sprintf(`"%s"`, f.DefValue)
}
options = append(options, []string{opt, f.Usage})
})
if len(options) > 0 {
b.WriteString("\nOptions:\n")
optionTable(&b, options)
}
fmt.Println(b.String())
if len(extra) > 0 {
fmt.Println(extra)
}
}
}