109 lines
1.9 KiB
Go
109 lines
1.9 KiB
Go
// Copyright (C) 2022 Marius Schellenberger
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package fs
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import (
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"os"
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"sync"
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"sync/atomic"
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"time"
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)
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func now() int64 {
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return time.Now().UTC().Unix()
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}
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type MetadataMap map[string]*Metadata
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type Metadata struct {
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mu sync.RWMutex `json:"-"`
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fs *FS `json:"-"`
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f *os.File `json:"-"`
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name string `json:"-"`
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Size int64 `json:"s"`
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Atime int64 `json:"a"`
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Chunks Chunks `json:"c"`
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preload bool `json:"-"`
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}
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func (md *Metadata) Delete() error {
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md.mu.Lock()
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defer md.mu.Unlock()
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md.Chunks = Chunks{}
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md.f.Close()
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md.f = nil
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atomic.StoreInt64(&md.Atime, now())
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return md.fs.RemoveDst(md.name)
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}
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func (md *Metadata) HasChunk(off int64, n int) bool {
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md.mu.RLock()
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defer md.mu.RUnlock()
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return md.Chunks.Exists(off, n, md.Size)
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}
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func (md *Metadata) AddChunk(off int64, n int) {
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md.mu.Lock()
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defer md.mu.Unlock()
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md.Chunks.Add(off, n)
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}
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func (md *Metadata) ReadAt(p []byte, pos int64) (int, error) {
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if md.f == nil {
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err := md.openCacheFile()
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if err != nil {
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return 0, err
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}
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}
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atomic.StoreInt64(&md.Atime, now())
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return md.f.ReadAt(p, pos)
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}
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func (md *Metadata) WriteAt(data []byte, pos int64) (int, error) {
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if md.f == nil {
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err := md.openCacheFile()
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if err != nil {
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return 0, err
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}
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}
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atomic.StoreInt64(&md.Atime, now())
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md.fs.q.Add(len(data))
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return md.f.WriteAt(data, pos)
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}
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func (md *Metadata) openCacheFile() error {
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md.mu.Lock()
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defer md.mu.Unlock()
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if md.f != nil {
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return nil
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}
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f, err := md.fs.openCacheFile(md.name, md.Size)
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md.f = f
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return err
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}
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func (md *Metadata) Preload() bool {
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md.mu.Lock()
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defer md.mu.Unlock()
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if md.preload {
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return true
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}
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md.preload = true
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return false
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}
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func (md *Metadata) UnlockPreload() {
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md.mu.Lock()
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defer md.mu.Unlock()
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md.preload = false
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}
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func (md *Metadata) Stat() (os.FileInfo, error) {
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if md.f == nil {
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err := md.openCacheFile()
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if err != nil {
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return nil, err
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}
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}
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return md.f.Stat()
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}
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