github.com/LandonTClipp/afero@v1.3.6-0.20200907052150-97f9d166c7a3/symlink.go (about)

     1  // Copyright © 2018 Steve Francia <spf@spf13.com>.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  // http://www.apache.org/licenses/LICENSE-2.0
     7  //
     8  // Unless required by applicable law or agreed to in writing, software
     9  // distributed under the License is distributed on an "AS IS" BASIS,
    10  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package afero
    15  
    16  import (
    17  	"errors"
    18  )
    19  
    20  // Symlinker is an optional interface in Afero. It is only implemented by the
    21  // filesystems saying so.
    22  // It indicates support for 3 symlink related interfaces that implement the
    23  // behaviors of the os methods:
    24  //    - Lstat
    25  //    - Symlink, and
    26  //    - Readlink
    27  type Symlinker interface {
    28  	Lstater
    29  	Linker
    30  	LinkReader
    31  }
    32  
    33  // Linker is an optional interface in Afero. It is only implemented by the
    34  // filesystems saying so.
    35  // It will call Symlink if the filesystem itself is, or it delegates to, the os filesystem,
    36  // or the filesystem otherwise supports Symlink's.
    37  type Linker interface {
    38  	SymlinkIfPossible(oldname, newname string) error
    39  }
    40  
    41  // ErrNoSymlink is the error that will be wrapped in an os.LinkError if a file system
    42  // does not support Symlink's either directly or through its delegated filesystem.
    43  // As expressed by support for the Linker interface.
    44  var ErrNoSymlink = errors.New("symlink not supported")
    45  
    46  // LinkReader is an optional interface in Afero. It is only implemented by the
    47  // filesystems saying so.
    48  type LinkReader interface {
    49  	ReadlinkIfPossible(name string) (string, error)
    50  }
    51  
    52  // ErrNoReadlink is the error that will be wrapped in an os.Path if a file system
    53  // does not support the readlink operation either directly or through its delegated filesystem.
    54  // As expressed by support for the LinkReader interface.
    55  var ErrNoReadlink = errors.New("readlink not supported")