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

     1  //
     2  //  Copyright 2020 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  	"errors"
    21  	"fmt"
    22  	"io/fs"
    23  	"os"
    24  )
    25  
    26  // DirExists checks if a path exists and is a directory.
    27  func DirExists(vfs VFSBase, path string) (bool, error) {
    28  	fi, err := vfs.Stat(path)
    29  	if err == nil && fi.IsDir() {
    30  		return true, nil
    31  	}
    32  
    33  	if errors.Is(err, fs.ErrNotExist) {
    34  		return false, nil
    35  	}
    36  
    37  	return false, err
    38  }
    39  
    40  // Exists Check if a file or directory exists.
    41  func Exists(vfs VFSBase, path string) (bool, error) {
    42  	_, err := vfs.Stat(path)
    43  	if err == nil {
    44  		return true, nil
    45  	}
    46  
    47  	if errors.Is(err, fs.ErrNotExist) {
    48  		return false, nil
    49  	}
    50  
    51  	return false, err
    52  }
    53  
    54  // IsDir checks if a given path is a directory.
    55  func IsDir(vfs VFSBase, path string) (bool, error) {
    56  	fi, err := vfs.Stat(path)
    57  	if err != nil {
    58  		return false, err
    59  	}
    60  
    61  	return fi.IsDir(), nil
    62  }
    63  
    64  // IsEmpty checks if a given file or directory is empty.
    65  func IsEmpty(vfs VFSBase, path string) (bool, error) {
    66  	if b, _ := Exists(vfs, path); !b {
    67  		return false, fmt.Errorf("%q path does not exist", path)
    68  	}
    69  
    70  	fi, err := vfs.Stat(path)
    71  	if err != nil {
    72  		return false, err
    73  	}
    74  
    75  	if fi.IsDir() {
    76  		f, err := vfs.OpenFile(path, os.O_RDONLY, 0)
    77  		if err != nil {
    78  			return false, err
    79  		}
    80  
    81  		defer f.Close()
    82  
    83  		list, err := f.ReadDir(-1)
    84  		if err != nil {
    85  			return false, err
    86  		}
    87  
    88  		return len(list) == 0, nil
    89  	}
    90  
    91  	return fi.Size() == 0, nil
    92  }