github.com/avfs/avfs@v0.33.1-0.20240303173310-c6ba67c33eb7/umask.go (about)

     1  //
     2  //  Copyright 2023 The AVFS authors
     3  //
     4  //  Licensed under the Apache License, Version 2.0 (the "License");
     5  //  you may not use this file except in compliance with the License.
     6  //  You may obtain a copy of the License at
     7  //
     8  //  	http://www.apache.org/licenses/LICENSE-2.0
     9  //
    10  //  Unless required by applicable law or agreed to in writing, software
    11  //  distributed under the License is distributed on an "AS IS" BASIS,
    12  //  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  //  See the License for the specific language governing permissions and
    14  //  limitations under the License.
    15  //
    16  
    17  package avfs
    18  
    19  import (
    20  	"io/fs"
    21  	"sync/atomic"
    22  )
    23  
    24  // UMasker is the interface that wraps umask related methods.
    25  type UMasker interface {
    26  	// SetUMask sets the file mode creation mask.
    27  	SetUMask(mask fs.FileMode) error
    28  
    29  	// UMask returns the file mode creation mask.
    30  	UMask() fs.FileMode
    31  }
    32  
    33  // UMaskFn provides UMask functions to file systems.
    34  type UMaskFn struct {
    35  	umask fs.FileMode // umask is the user file creation mode mask.
    36  }
    37  
    38  // SetUMask sets the file mode creation mask.
    39  func (umf *UMaskFn) SetUMask(mask fs.FileMode) error {
    40  	atomic.StoreUint32((*uint32)(&umf.umask), uint32(mask))
    41  
    42  	return nil
    43  }
    44  
    45  // UMask returns the file mode creation mask.
    46  func (umf *UMaskFn) UMask() fs.FileMode {
    47  	m := atomic.LoadUint32((*uint32)(&umf.umask))
    48  
    49  	return fs.FileMode(m)
    50  }