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Code Issues Releases Activity

added offline mode

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This commit is contained in:
ston1th 2022-03-14 00:06:06 +01:00
commit d2b91f2db4
4 changed files with 105 additions and 38 deletions
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32
pkg/fs/file.go
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@ -3,6 +3,7 @@
package fs
import (
"errors"
"io"
"os"
@ -10,10 +11,11 @@ import (
)
type File struct {
log logr.Logger
f *os.File
md *Metadata
offset int64
log logr.Logger
f *os.File
md *Metadata
offset int64
offline bool
}
type preload struct {
@ -38,23 +40,34 @@ func (p *preload) Read(data []byte) (n int, err error) {
}
func (f *File) Preload(unlock func()) {
f.log.V(2).Info("preload started")
log := f.log
if f.offline {
log.V(2).Error(errors.New("no preload in offline mode"), "error preloading file")
unlock()
return
}
log.V(2).Info("preload started")
p := &preload{f: f}
_, err := io.Copy(io.Discard, p)
if err != nil && err != io.EOF {
f.log.Error(err, "error preloading file")
log.Error(err, "error preloading file")
}
f.log.V(2).Info("preload finished", "skipped", p.skipped, "written", p.written)
log.V(2).Info("preload finished", "skipped", p.skipped, "written", p.written)
unlock()
}
func (f *File) Read(p []byte) (n int, err error) {
log := f.log
if f.hasChunk(len(p)) {
n, err = f.md.ReadAt(p, f.offset)
if err != nil {
log.Error(err, "error reading cache file")
return
}
_, err = f.Seek(int64(n), io.SeekCurrent)
if err != nil {
log.Error(err, "error seeking source file")
}
return
}
return f.readWithoutCache(p)
@ -69,8 +82,12 @@ func (f *File) hasChunk(n int) bool {
}
func (f *File) readWithoutCache(p []byte) (n int, err error) {
if f.offline {
return 0, io.EOF
}
n, err = f.f.Read(p)
if err != nil {
f.log.Error(err, "error reading source file")
return
}
f.md.WriteAt(p, f.offset)
@ -82,6 +99,7 @@ func (f *File) readWithoutCache(p []byte) (n int, err error) {
func (f *File) Seek(offset int64, whence int) (n int64, err error) {
n, err = f.f.Seek(offset, whence)
if err != nil {
f.log.Error(err, "error seeking source file")
return
}
switch whence {