git.r.bdr.sh - rbdr/mobius/blob - hotline/file_wrapper.go

   1 package hotline
   2
   3 import (
   4         "encoding/binary"
   5         "errors"
   6         "fmt"
   7         "io"
   8         "io/fs"
   9         "os"
  10         "path/filepath"
  11 )
  12
  13 const (
  14         incompleteFileSuffix = ".incomplete"
  15         infoForkNameTemplate = ".info_%s" // template string for info fork filenames
  16         rsrcForkNameTemplate = ".rsrc_%s" // template string for resource fork filenames
  17 )
  18
  19 // fileWrapper encapsulates the data, info, and resource forks of a Hotline file and provides methods to manage the files.
  20 type fileWrapper struct {
  21         fs             FileStore
  22         name           string // name of the file
  23         path           string // path to file directory
  24         dataPath       string // path to the file data fork
  25         dataOffset     int64
  26         rsrcPath       string // path to the file resource fork
  27         infoPath       string // path to the file information fork
  28         incompletePath string // path to partially transferred temp file
  29         saveMetaData   bool   // if true, enables saving of info and resource forks in sidecar files
  30         infoFork       *FlatFileInformationFork
  31         ffo            *flattenedFileObject
  32 }
  33
  34 func newFileWrapper(fs FileStore, path string, dataOffset int64) (*fileWrapper, error) {
  35         dir := filepath.Dir(path)
  36         fName := filepath.Base(path)
  37         f := fileWrapper{
  38                 fs:             fs,
  39                 name:           fName,
  40                 path:           dir,
  41                 dataPath:       path,
  42                 dataOffset:     dataOffset,
  43                 rsrcPath:       filepath.Join(dir, fmt.Sprintf(rsrcForkNameTemplate, fName)),
  44                 infoPath:       filepath.Join(dir, fmt.Sprintf(infoForkNameTemplate, fName)),
  45                 incompletePath: filepath.Join(dir, fName+incompleteFileSuffix),
  46                 ffo:            &flattenedFileObject{},
  47         }
  48
  49         var err error
  50         f.ffo, err = f.flattenedFileObject()
  51         if err != nil {
  52                 return nil, err
  53         }
  54
  55         return &f, nil
  56 }
  57
  58 func (f *fileWrapper) totalSize() []byte {
  59         var s int64
  60         size := make([]byte, 4)
  61
  62         info, err := f.fs.Stat(f.dataPath)
  63         if err == nil {
  64                 s += info.Size() - f.dataOffset
  65         }
  66
  67         info, err = f.fs.Stat(f.rsrcPath)
  68         if err == nil {
  69                 s += info.Size()
  70         }
  71
  72         binary.BigEndian.PutUint32(size, uint32(s))
  73
  74         return size
  75 }
  76
  77 func (f *fileWrapper) rsrcForkSize() (s [4]byte) {
  78         info, err := f.fs.Stat(f.rsrcPath)
  79         if err != nil {
  80                 return s
  81         }
  82
  83         binary.BigEndian.PutUint32(s[:], uint32(info.Size()))
  84         return s
  85 }
  86
  87 func (f *fileWrapper) rsrcForkHeader() FlatFileForkHeader {
  88         return FlatFileForkHeader{
  89                 ForkType:        [4]byte{0x4D, 0x41, 0x43, 0x52}, // "MACR"
  90                 CompressionType: [4]byte{},
  91                 RSVD:            [4]byte{},
  92                 DataSize:        f.rsrcForkSize(),
  93         }
  94 }
  95
  96 func (f *fileWrapper) incompleteDataName() string {
  97         return f.name + incompleteFileSuffix
  98 }
  99
 100 func (f *fileWrapper) rsrcForkName() string {
 101         return fmt.Sprintf(rsrcForkNameTemplate, f.name)
 102 }
 103
 104 func (f *fileWrapper) infoForkName() string {
 105         return fmt.Sprintf(infoForkNameTemplate, f.name)
 106 }
 107
 108 func (f *fileWrapper) rsrcForkWriter() (io.Writer, error) {
 109         file, err := os.OpenFile(f.rsrcPath, os.O_CREATE|os.O_WRONLY, 0644)
 110         if err != nil {
 111                 return nil, err
 112         }
 113
 114         return file, nil
 115 }
 116
 117 func (f *fileWrapper) infoForkWriter() (io.Writer, error) {
 118         file, err := os.OpenFile(f.infoPath, os.O_CREATE|os.O_WRONLY, 0644)
 119         if err != nil {
 120                 return nil, err
 121         }
 122
 123         return file, nil
 124 }
 125
 126 func (f *fileWrapper) incFileWriter() (io.Writer, error) {
 127         file, err := os.OpenFile(f.incompletePath, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0644)
 128         if err != nil {
 129                 return nil, err
 130         }
 131
 132         return file, nil
 133 }
 134
 135 func (f *fileWrapper) dataForkReader() (io.Reader, error) {
 136         return f.fs.Open(f.dataPath)
 137 }
 138
 139 func (f *fileWrapper) rsrcForkFile() (*os.File, error) {
 140         return f.fs.Open(f.rsrcPath)
 141 }
 142
 143 func (f *fileWrapper) dataFile() (os.FileInfo, error) {
 144         if fi, err := f.fs.Stat(f.dataPath); err == nil {
 145                 return fi, nil
 146         }
 147         if fi, err := f.fs.Stat(f.incompletePath); err == nil {
 148                 return fi, nil
 149         }
 150
 151         return nil, errors.New("file or directory not found")
 152 }
 153
 154 // move a fileWrapper and its associated metadata files to newPath
 155 func (f *fileWrapper) move(newPath string) error {
 156         err := f.fs.Rename(f.dataPath, filepath.Join(newPath, f.name))
 157         if err != nil {
 158                 // TODO
 159         }
 160
 161         err = f.fs.Rename(f.incompletePath, filepath.Join(newPath, f.incompleteDataName()))
 162         if err != nil {
 163                 // TODO
 164         }
 165
 166         err = f.fs.Rename(f.rsrcPath, filepath.Join(newPath, f.rsrcForkName()))
 167         if err != nil {
 168                 // TODO
 169         }
 170
 171         err = f.fs.Rename(f.infoPath, filepath.Join(newPath, f.infoForkName()))
 172         if err != nil {
 173                 // TODO
 174         }
 175
 176         return nil
 177 }
 178
 179 // delete a fileWrapper and its associated metadata files if they exist
 180 func (f *fileWrapper) delete() error {
 181         err := f.fs.RemoveAll(f.dataPath)
 182         if err != nil {
 183                 // TODO
 184         }
 185
 186         err = f.fs.Remove(f.incompletePath)
 187         if err != nil {
 188                 // TODO
 189         }
 190
 191         err = f.fs.Remove(f.rsrcPath)
 192         if err != nil {
 193                 // TODO
 194         }
 195
 196         err = f.fs.Remove(f.infoPath)
 197         if err != nil {
 198                 // TODO
 199         }
 200
 201         return nil
 202 }
 203
 204 func (f *fileWrapper) flattenedFileObject() (*flattenedFileObject, error) {
 205         dataSize := make([]byte, 4)
 206         mTime := make([]byte, 8)
 207
 208         ft := defaultFileType
 209
 210         fileInfo, err := f.fs.Stat(f.dataPath)
 211         if err != nil && !errors.Is(err, fs.ErrNotExist) {
 212                 return nil, err
 213         }
 214         if errors.Is(err, fs.ErrNotExist) {
 215                 fileInfo, err = f.fs.Stat(f.incompletePath)
 216                 if err == nil {
 217                         mTime = toHotlineTime(fileInfo.ModTime())
 218                         binary.BigEndian.PutUint32(dataSize, uint32(fileInfo.Size()-f.dataOffset))
 219                         ft, _ = fileTypeFromInfo(fileInfo)
 220                 }
 221         } else {
 222                 mTime = toHotlineTime(fileInfo.ModTime())
 223                 binary.BigEndian.PutUint32(dataSize, uint32(fileInfo.Size()-f.dataOffset))
 224                 ft, _ = fileTypeFromInfo(fileInfo)
 225         }
 226
 227         f.ffo.FlatFileHeader = FlatFileHeader{
 228                 Format:    [4]byte{0x46, 0x49, 0x4c, 0x50}, // "FILP"
 229                 Version:   [2]byte{0, 1},
 230                 RSVD:      [16]byte{},
 231                 ForkCount: [2]byte{0, 2},
 232         }
 233
 234         _, err = f.fs.Stat(f.infoPath)
 235         if err == nil {
 236                 b, err := f.fs.ReadFile(f.infoPath)
 237                 if err != nil {
 238                         return nil, err
 239                 }
 240
 241                 f.ffo.FlatFileHeader.ForkCount[1] = 3
 242
 243                 if err := f.ffo.FlatFileInformationFork.UnmarshalBinary(b); err != nil {
 244                         return nil, err
 245                 }
 246         } else {
 247                 f.ffo.FlatFileInformationFork = FlatFileInformationFork{
 248                         Platform:         []byte("AMAC"), // TODO: Remove hardcode to support "AWIN" Platform (maybe?)
 249                         TypeSignature:    []byte(ft.TypeCode),
 250                         CreatorSignature: []byte(ft.CreatorCode),
 251                         Flags:            []byte{0, 0, 0, 0},
 252                         PlatformFlags:    []byte{0, 0, 1, 0}, // TODO: What is this?
 253                         RSVD:             make([]byte, 32),
 254                         CreateDate:       mTime, // some filesystems don't support createTime
 255                         ModifyDate:       mTime,
 256                         NameScript:       []byte{0, 0},
 257                         Name:             []byte(f.name),
 258                         NameSize:         []byte{0, 0},
 259                         CommentSize:      []byte{0, 0},
 260                         Comment:          []byte{},
 261                 }
 262                 binary.BigEndian.PutUint16(f.ffo.FlatFileInformationFork.NameSize, uint16(len(f.name)))
 263         }
 264
 265         f.ffo.FlatFileInformationForkHeader = FlatFileForkHeader{
 266                 ForkType:        [4]byte{0x49, 0x4E, 0x46, 0x4F}, // "INFO"
 267                 CompressionType: [4]byte{},
 268                 RSVD:            [4]byte{},
 269                 DataSize:        f.ffo.FlatFileInformationFork.Size(),
 270         }
 271
 272         f.ffo.FlatFileDataForkHeader = FlatFileForkHeader{
 273                 ForkType:        [4]byte{0x44, 0x41, 0x54, 0x41}, // "DATA"
 274                 CompressionType: [4]byte{},
 275                 RSVD:            [4]byte{},
 276                 DataSize:        [4]byte{dataSize[0], dataSize[1], dataSize[2], dataSize[3]},
 277         }
 278         f.ffo.FlatFileResForkHeader = f.rsrcForkHeader()
 279
 280         return f.ffo, nil
 281 }