github.com/hugh712/snapd@v0.0.0-20200910133618-1a99902bd583/cmd/snap-repair/main.go (about)

     1  // -*- Mode: Go; indent-tabs-mode: t -*-
     2  
     3  /*
     4   * Copyright (C) 2017-2020 Canonical Ltd
     5   *
     6   * This program is free software: you can redistribute it and/or modify
     7   * it under the terms of the GNU General Public License version 3 as
     8   * published by the Free Software Foundation.
     9   *
    10   * This program is distributed in the hope that it will be useful,
    11   * but WITHOUT ANY WARRANTY; without even the implied warranty of
    12   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    13   * GNU General Public License for more details.
    14   *
    15   * You should have received a copy of the GNU General Public License
    16   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
    17   *
    18   */
    19  
    20  package main
    21  
    22  import (
    23  	"fmt"
    24  	"io"
    25  	"os"
    26  
    27  	// TODO: consider not using go-flags at all
    28  	"github.com/jessevdk/go-flags"
    29  
    30  	"github.com/snapcore/snapd/logger"
    31  	"github.com/snapcore/snapd/release"
    32  	"github.com/snapcore/snapd/snapdenv"
    33  	"github.com/snapcore/snapd/snapdtool"
    34  )
    35  
    36  var (
    37  	Stdout io.Writer = os.Stdout
    38  	Stderr io.Writer = os.Stderr
    39  
    40  	opts   struct{}
    41  	parser *flags.Parser = flags.NewParser(&opts, flags.HelpFlag|flags.PassDoubleDash|flags.PassAfterNonOption)
    42  )
    43  
    44  const (
    45  	shortHelp = "Repair an Ubuntu Core system"
    46  	longHelp  = `
    47  snap-repair is a tool to fetch and run repair assertions
    48  which are used to do emergency repairs on the device.
    49  `
    50  )
    51  
    52  func init() {
    53  	err := logger.SimpleSetup()
    54  	if err != nil {
    55  		fmt.Fprintf(Stderr, "WARNING: failed to activate logging: %v\n", err)
    56  	}
    57  }
    58  
    59  var errOnClassic = fmt.Errorf("cannot use snap-repair on a classic system")
    60  
    61  func main() {
    62  	if err := run(); err != nil {
    63  		fmt.Fprintf(Stderr, "error: %v\n", err)
    64  		if err != errOnClassic {
    65  			os.Exit(1)
    66  		}
    67  	}
    68  }
    69  
    70  var osGetuid = os.Getuid
    71  
    72  func run() error {
    73  	if release.OnClassic {
    74  		return errOnClassic
    75  	}
    76  	if osGetuid() != 0 {
    77  		return fmt.Errorf("must be run as root")
    78  	}
    79  	snapdenv.SetUserAgentFromVersion(snapdtool.Version, nil, "snap-repair")
    80  
    81  	if err := parseArgs(os.Args[1:]); err != nil {
    82  		return err
    83  	}
    84  
    85  	return nil
    86  }
    87  
    88  func parseArgs(args []string) error {
    89  	parser.ShortDescription = shortHelp
    90  	parser.LongDescription = longHelp
    91  
    92  	_, err := parser.ParseArgs(args)
    93  	return err
    94  }