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// Copyright © 2018 Steve Francia <[email protected]>.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package afero
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import (
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	"errors"
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)
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// Symlinker is an optional interface in Afero. It is only implemented by the
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// filesystems saying so.
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// It indicates support for 3 symlink related interfaces that implement the
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// behaviors of the os methods:
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//   - Lstat
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//   - Symlink, and
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//   - Readlink
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type Symlinker interface {
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	Lstater
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	Linker
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	LinkReader
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}
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// Linker is an optional interface in Afero. It is only implemented by the
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// filesystems saying so.
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// It will call Symlink if the filesystem itself is, or it delegates to, the os filesystem,
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// or the filesystem otherwise supports Symlink's.
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type Linker interface {
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	SymlinkIfPossible(oldname, newname string) error
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}
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// ErrNoSymlink is the error that will be wrapped in an os.LinkError if a file system
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// does not support Symlink's either directly or through its delegated filesystem.
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// As expressed by support for the Linker interface.
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var ErrNoSymlink = errors.New("symlink not supported")
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// LinkReader is an optional interface in Afero. It is only implemented by the
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// filesystems saying so.
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type LinkReader interface {
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	ReadlinkIfPossible(name string) (string, error)
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}
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// ErrNoReadlink is the error that will be wrapped in an os.Path if a file system
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// does not support the readlink operation either directly or through its delegated filesystem.
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// As expressed by support for the LinkReader interface.
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var ErrNoReadlink = errors.New("readlink not supported")
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