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|
package main
import (
"flag"
"fmt"
"os"
"path/filepath"
)
type subcommand interface {
registerFlags(*flag.FlagSet)
run(...string) error
}
func whichSubcommand(name string) (subcommand, bool) {
switch filepath.Base(name) {
case "enc":
return &encryptOptions{
passwordIn: termReadPassword,
passwordOut: os.Stderr,
stdin: os.Stdin,
stdout: os.Stdout,
}, true
case "dec":
return &decryptOptions{
passwordIn: termReadPassword,
stdin: os.Stdin,
stdout: os.Stdout,
}, true
default:
return nil, false
}
}
func run(args []string) error {
cmd, ok := whichSubcommand(args[0])
if !ok {
if len(args) < 2 {
return fmt.Errorf("missing subcommand")
}
cmd, ok = whichSubcommand(args[1])
if !ok {
return fmt.Errorf("invalid subcommand %q", args[1])
}
args = args[1:]
}
cmd.registerFlags(flag.CommandLine)
flag.CommandLine.Parse(args[1:])
return cmd.run(flag.Args()...)
}
func main() {
if err := run(os.Args); err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
}
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