github.com/bpfs/defs@v0.0.15/afero/tarfs/file.go (about)

     1  package tarfs
     2  
     3  import (
     4  	"archive/tar"
     5  	"bytes"
     6  	"os"
     7  	"path/filepath"
     8  	"sort"
     9  	"syscall"
    10  
    11  	"github.com/bpfs/defs/afero"
    12  )
    13  
    14  type File struct {
    15  	h      *tar.Header
    16  	data   *bytes.Reader
    17  	closed bool
    18  	fs     *Fs
    19  }
    20  
    21  func (f *File) Close() error {
    22  	if f.closed {
    23  		return afero.ErrFileClosed
    24  	}
    25  
    26  	f.closed = true
    27  	f.h = nil
    28  	f.data = nil
    29  	f.fs = nil
    30  
    31  	return nil
    32  }
    33  
    34  func (f *File) Read(p []byte) (n int, err error) {
    35  	if f.closed {
    36  		return 0, afero.ErrFileClosed
    37  	}
    38  
    39  	if f.h.Typeflag == tar.TypeDir {
    40  		return 0, syscall.EISDIR
    41  	}
    42  
    43  	return f.data.Read(p)
    44  }
    45  
    46  func (f *File) ReadAt(p []byte, off int64) (n int, err error) {
    47  	if f.closed {
    48  		return 0, afero.ErrFileClosed
    49  	}
    50  
    51  	if f.h.Typeflag == tar.TypeDir {
    52  		return 0, syscall.EISDIR
    53  	}
    54  
    55  	return f.data.ReadAt(p, off)
    56  }
    57  
    58  func (f *File) Seek(offset int64, whence int) (int64, error) {
    59  	if f.closed {
    60  		return 0, afero.ErrFileClosed
    61  	}
    62  
    63  	if f.h.Typeflag == tar.TypeDir {
    64  		return 0, syscall.EISDIR
    65  	}
    66  
    67  	return f.data.Seek(offset, whence)
    68  }
    69  
    70  func (f *File) Write(p []byte) (n int, err error) { return 0, syscall.EROFS }
    71  
    72  func (f *File) WriteAt(p []byte, off int64) (n int, err error) { return 0, syscall.EROFS }
    73  
    74  func (f *File) Name() string {
    75  	return filepath.Join(splitpath(f.h.Name))
    76  }
    77  
    78  func (f *File) getDirectoryNames() ([]string, error) {
    79  	d, ok := f.fs.files[f.Name()]
    80  	if !ok {
    81  		return nil, &os.PathError{Op: "readdir", Path: f.Name(), Err: syscall.ENOENT}
    82  	}
    83  
    84  	var names []string
    85  	for n := range d {
    86  		names = append(names, n)
    87  	}
    88  	sort.Strings(names)
    89  
    90  	return names, nil
    91  }
    92  
    93  func (f *File) Readdir(count int) ([]os.FileInfo, error) {
    94  	if f.closed {
    95  		return nil, afero.ErrFileClosed
    96  	}
    97  
    98  	if !f.h.FileInfo().IsDir() {
    99  		return nil, syscall.ENOTDIR
   100  	}
   101  
   102  	names, err := f.getDirectoryNames()
   103  	if err != nil {
   104  		return nil, err
   105  	}
   106  
   107  	d := f.fs.files[f.Name()]
   108  	var fi []os.FileInfo
   109  	for _, n := range names {
   110  		if n == "" {
   111  			continue
   112  		}
   113  
   114  		f := d[n]
   115  		fi = append(fi, f.h.FileInfo())
   116  		if count > 0 && len(fi) >= count {
   117  			break
   118  		}
   119  	}
   120  
   121  	return fi, nil
   122  }
   123  
   124  func (f *File) Readdirnames(n int) ([]string, error) {
   125  	fi, err := f.Readdir(n)
   126  	if err != nil {
   127  		return nil, err
   128  	}
   129  
   130  	var names []string
   131  	for _, f := range fi {
   132  		names = append(names, f.Name())
   133  	}
   134  
   135  	return names, nil
   136  }
   137  
   138  func (f *File) Stat() (os.FileInfo, error) { return f.h.FileInfo(), nil }
   139  
   140  func (f *File) Sync() error { return nil }
   141  
   142  func (f *File) Truncate(size int64) error { return syscall.EROFS }
   143  
   144  func (f *File) WriteString(s string) (ret int, err error) { return 0, syscall.EROFS }