85 lines
1.9 KiB
Go
85 lines
1.9 KiB
Go
package torrentfs
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import (
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"context"
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"io"
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"github.com/anacrolix/fuse"
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"github.com/anacrolix/fuse/fs"
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"github.com/anacrolix/missinggo/v2"
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"github.com/anacrolix/torrent"
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)
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type fileHandle struct {
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fn fileNode
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r torrent.Reader
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}
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var _ interface {
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fs.HandleReader
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fs.HandleReleaser
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} = fileHandle{}
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func (me fileHandle) Read(ctx context.Context, req *fuse.ReadRequest, resp *fuse.ReadResponse) error {
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torrentfsReadRequests.Add(1)
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if req.Dir {
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panic("read on directory")
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}
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r := me.r
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pos, err := r.Seek(req.Offset, io.SeekStart)
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if err != nil {
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panic(err)
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}
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if pos != req.Offset {
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panic("seek failed")
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}
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resp.Data = resp.Data[:req.Size]
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readDone := make(chan struct{})
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ctx, cancel := context.WithCancel(ctx)
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var readErr error
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go func() {
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defer close(readDone)
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me.fn.FS.mu.Lock()
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me.fn.FS.blockedReads++
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me.fn.FS.event.Broadcast()
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me.fn.FS.mu.Unlock()
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var n int
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r := missinggo.ContextedReader{r, ctx}
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// log.Printf("reading %v bytes at %v", len(resp.Data), req.Offset)
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if true {
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// A user reported on that on freebsd 12.2, the system requires that reads are
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// completely filled. Their system only asks for 64KiB at a time. I've seen systems that
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// can demand up to 16MiB at a time, so this gets tricky. For now, I'll restore the old
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// behaviour from before 2a7352a, which nobody reported problems with.
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n, readErr = io.ReadFull(r, resp.Data)
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} else {
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n, readErr = r.Read(resp.Data)
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if readErr == io.EOF {
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readErr = nil
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}
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}
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resp.Data = resp.Data[:n]
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}()
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defer func() {
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<-readDone
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me.fn.FS.mu.Lock()
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me.fn.FS.blockedReads--
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me.fn.FS.event.Broadcast()
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me.fn.FS.mu.Unlock()
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}()
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defer cancel()
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select {
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case <-readDone:
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return readErr
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case <-me.fn.FS.destroyed:
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return fuse.EIO
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case <-ctx.Done():
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return fuse.EINTR
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}
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}
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func (me fileHandle) Release(context.Context, *fuse.ReleaseRequest) error {
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return me.r.Close()
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}
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