gitee.com/mysnapcore/mysnapd@v0.1.0/asserts/fsentryutils.go (about)

     1  // -*- Mode: Go; indent-tabs-mode: t -*-
     2  
     3  /*
     4   * Copyright (C) 2015-2016 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 asserts
    21  
    22  import (
    23  	"fmt"
    24  	"io/ioutil"
    25  	"os"
    26  	"path/filepath"
    27  
    28  	"gitee.com/mysnapcore/mysnapd/osutil"
    29  )
    30  
    31  // utilities to read/write fs entries
    32  
    33  func ensureTop(path string) error {
    34  	err := os.MkdirAll(path, 0775)
    35  	if err != nil {
    36  		return fmt.Errorf("cannot create assert storage root: %v", err)
    37  	}
    38  	info, err := os.Stat(path)
    39  	if err != nil {
    40  		return fmt.Errorf("cannot create assert storage root: %v", err)
    41  	}
    42  	if info.Mode().Perm()&0002 != 0 {
    43  		return fmt.Errorf("assert storage root unexpectedly world-writable: %v", path)
    44  	}
    45  	return nil
    46  }
    47  
    48  func atomicWriteEntry(data []byte, secret bool, top string, subpath ...string) error {
    49  	fpath := filepath.Join(top, filepath.Join(subpath...))
    50  	dir := filepath.Dir(fpath)
    51  	err := os.MkdirAll(dir, 0775)
    52  	if err != nil {
    53  		return err
    54  	}
    55  	fperm := 0664
    56  	if secret {
    57  		fperm = 0600
    58  	}
    59  	return osutil.AtomicWriteFile(fpath, data, os.FileMode(fperm), 0)
    60  }
    61  
    62  func entryExists(top string, subpath ...string) bool {
    63  	fpath := filepath.Join(top, filepath.Join(subpath...))
    64  	return osutil.FileExists(fpath)
    65  }
    66  
    67  func readEntry(top string, subpath ...string) ([]byte, error) {
    68  	fpath := filepath.Join(top, filepath.Join(subpath...))
    69  	return ioutil.ReadFile(fpath)
    70  }
    71  
    72  func removeEntry(top string, subpath ...string) error {
    73  	fpath := filepath.Join(top, filepath.Join(subpath...))
    74  	return os.Remove(fpath)
    75  }