github.com/keybase/client/go@v0.0.0-20240309051027-028f7c731f8b/kbfs/libfuse/sync_from_server_file.go (about)

     1  // Copyright 2016 Keybase Inc. All rights reserved.
     2  // Use of this source code is governed by a BSD
     3  // license that can be found in the LICENSE file.
     4  //
     5  //go:build !windows
     6  // +build !windows
     7  
     8  package libfuse
     9  
    10  import (
    11  	"bazil.org/fuse"
    12  	"bazil.org/fuse/fs"
    13  	"github.com/keybase/client/go/kbfs/data"
    14  	"github.com/keybase/client/go/kbfs/libfs"
    15  	"github.com/keybase/client/go/kbfs/libkbfs"
    16  	"golang.org/x/net/context"
    17  )
    18  
    19  // SyncFromServerFile represents a write-only file when any write of
    20  // at least one byte triggers a sync of the folder from the server.
    21  // A sync:
    22  //
    23  //   - Waits for any outstanding conflict resolution tasks to finish
    24  //     (and it fails if the TLF is still in staged mode after waiting for
    25  //     CR).
    26  //   - Checks with the server for what the latest revision is for the folder.
    27  //   - Fetches and applies any missing revisions.
    28  //   - Waits for all outstanding block archive tasks to complete.
    29  //   - Waits for all outstanding quota reclamation tasks to complete.
    30  type SyncFromServerFile struct {
    31  	folder *Folder
    32  }
    33  
    34  var _ fs.Node = (*SyncFromServerFile)(nil)
    35  
    36  // Attr implements the fs.Node interface for SyncFromServerFile.
    37  func (f *SyncFromServerFile) Attr(ctx context.Context, a *fuse.Attr) error {
    38  	a.Size = 0
    39  	a.Mode = 0222
    40  	return nil
    41  }
    42  
    43  var _ fs.Handle = (*SyncFromServerFile)(nil)
    44  
    45  var _ fs.HandleWriter = (*SyncFromServerFile)(nil)
    46  
    47  // Write implements the fs.HandleWriter interface for SyncFromServerFile.
    48  func (f *SyncFromServerFile) Write(ctx context.Context, req *fuse.WriteRequest,
    49  	resp *fuse.WriteResponse) (err error) {
    50  	f.folder.fs.log.CDebugf(ctx, "SyncFromServerFile Write")
    51  	defer func() { err = f.folder.processError(ctx, libkbfs.WriteMode, err) }()
    52  	if len(req.Data) == 0 {
    53  		return nil
    54  	}
    55  	folderBranch := f.folder.getFolderBranch()
    56  	if folderBranch == (data.FolderBranch{}) {
    57  		// Nothing to do.
    58  		resp.Size = len(req.Data)
    59  		return nil
    60  	}
    61  
    62  	// Use a context with a nil CtxAppIDKey value so that
    63  	// notifications generated from this sync won't be discarded.
    64  	syncCtx := context.WithValue(ctx, libfs.CtxAppIDKey, nil)
    65  	err = f.folder.fs.config.KBFSOps().SyncFromServer(
    66  		syncCtx, folderBranch, nil)
    67  	if err != nil {
    68  		return err
    69  	}
    70  	f.folder.fs.NotificationGroupWait()
    71  	resp.Size = len(req.Data)
    72  	return nil
    73  }