path: root/vendor/bazil.org/fuse/fs/tree.go

// FUSE directory tree, for servers that wish to use it with the service loop.

package fs

import (
    "os"
    pathpkg "path"
    "strings"

    "golang.org/x/net/context"
)

import (
    "bazil.org/fuse"
)

// A Tree implements a basic read-only directory tree for FUSE.
// The Nodes contained in it may still be writable.
type Tree struct {
    tree
}

func (t *Tree) Root() (Node, error) {
    return &t.tree, nil
}

// Add adds the path to the tree, resolving to the given node.
// If path or a prefix of path has already been added to the tree,
// Add panics.
//
// Add is only safe to call before starting to serve requests.
func (t *Tree) Add(path string, node Node) {
    path = pathpkg.Clean("/" + path)[1:]
    elems := strings.Split(path, "/")
    dir := Node(&t.tree)
    for i, elem := range elems {
        dt, ok := dir.(*tree)
        if !ok {
            panic("fuse: Tree.Add for " + strings.Join(elems[:i], "/") + " and " + path)
        }
        n := dt.lookup(elem)
        if n != nil {
            if i+1 == len(elems) {
                panic("fuse: Tree.Add for " + path + " conflicts with " + elem)
            }
            dir = n
        } else {
            if i+1 == len(elems) {
                dt.add(elem, node)
            } else {
                dir = &tree{}
                dt.add(elem, dir)
            }
        }
    }
}

type treeDir struct {
    name string
    node Node
}

type tree struct {
    dir []treeDir
}

func (t *tree) lookup(name string) Node {
    for _, d := range t.dir {
        if d.name == name {
            return d.node
        }
    }
    return nil
}

func (t *tree) add(name string, n Node) {
    t.dir = append(t.dir, treeDir{name, n})
}

func (t *tree) Attr(ctx context.Context, a *fuse.Attr) error {
    a.Mode = os.ModeDir | 0555
    return nil
}

func (t *tree) Lookup(ctx context.Context, name string) (Node, error) {
    n := t.lookup(name)
    if n != nil {
        return n, nil
    }
    return nil, fuse.ENOENT
}

func (t *tree) ReadDirAll(ctx context.Context) ([]fuse.Dirent, error) {
    var out []fuse.Dirent
    for _, d := range t.dir {
        out = append(out, fuse.Dirent{Name: d.name})
    }
    return out, nil
}