github.com/core-coin/go-core/v2@v2.1.9/accounts/keystore/file_cache.go (about)

     1  // Copyright 2017 by the Authors
     2  // This file is part of the go-core library.
     3  //
     4  // The go-core library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-core library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-core library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package keystore
    18  
    19  import (
    20  	"io/ioutil"
    21  	"os"
    22  	"path/filepath"
    23  	"strings"
    24  	"sync"
    25  	"time"
    26  
    27  	mapset "github.com/deckarep/golang-set"
    28  
    29  	"github.com/core-coin/go-core/v2/log"
    30  )
    31  
    32  // fileCache is a cache of files seen during scan of keystore.
    33  type fileCache struct {
    34  	all     mapset.Set // Set of all files from the keystore folder
    35  	lastMod time.Time  // Last time instance when a file was modified
    36  	mu      sync.Mutex
    37  }
    38  
    39  // scan performs a new scan on the given directory, compares against the already
    40  // cached filenames, and returns file sets: creates, deletes, updates.
    41  func (fc *fileCache) scan(keyDir string) (mapset.Set, mapset.Set, mapset.Set, error) {
    42  	t0 := time.Now()
    43  
    44  	// List all the failes from the keystore folder
    45  	files, err := ioutil.ReadDir(keyDir)
    46  	if err != nil {
    47  		return nil, nil, nil, err
    48  	}
    49  	t1 := time.Now()
    50  
    51  	fc.mu.Lock()
    52  	defer fc.mu.Unlock()
    53  
    54  	// Iterate all the files and gather their metadata
    55  	all := mapset.NewThreadUnsafeSet()
    56  	mods := mapset.NewThreadUnsafeSet()
    57  
    58  	var newLastMod time.Time
    59  	for _, fi := range files {
    60  		path := filepath.Join(keyDir, fi.Name())
    61  		// Skip any non-key files from the folder
    62  		if nonKeyFile(fi) {
    63  			log.Trace("Ignoring file on account scan", "path", path)
    64  			continue
    65  		}
    66  		// Gather the set of all and fresly modified files
    67  		all.Add(path)
    68  
    69  		modified := fi.ModTime()
    70  		if modified.After(fc.lastMod) {
    71  			mods.Add(path)
    72  		}
    73  		if modified.After(newLastMod) {
    74  			newLastMod = modified
    75  		}
    76  	}
    77  	t2 := time.Now()
    78  
    79  	// Update the tracked files and return the three sets
    80  	deletes := fc.all.Difference(all)   // Deletes = previous - current
    81  	creates := all.Difference(fc.all)   // Creates = current - previous
    82  	updates := mods.Difference(creates) // Updates = modified - creates
    83  
    84  	fc.all, fc.lastMod = all, newLastMod
    85  	t3 := time.Now()
    86  
    87  	// Report on the scanning stats and return
    88  	log.Debug("FS scan times", "list", t1.Sub(t0), "set", t2.Sub(t1), "diff", t3.Sub(t2))
    89  	return creates, deletes, updates, nil
    90  }
    91  
    92  // nonKeyFile ignores editor backups, hidden files and folders/symlinks.
    93  func nonKeyFile(fi os.FileInfo) bool {
    94  	// Skip editor backups and UNIX-style hidden files.
    95  	if strings.HasSuffix(fi.Name(), "~") || strings.HasPrefix(fi.Name(), ".") {
    96  		return true
    97  	}
    98  	// Skip misc special files, directories (yes, symlinks too).
    99  	if fi.IsDir() || fi.Mode()&os.ModeType != 0 {
   100  		return true
   101  	}
   102  	return false
   103  }