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added missing return error in fat32 function, and swapped all to %w w…
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…rapping (#259)

Signed-off-by: Avi Deitcher <[email protected]>
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@deitch
deitch authored Sep 26, 2024
1 parent 1c5247c commit 142b4fd
Showing 1 changed file with 42 additions and 42 deletions.
84 changes: 42 additions & 42 deletions filesystem/fat32/fat32.go
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Original file line number Diff line number Diff line change
Expand Up @@ -257,17 +257,17 @@ func Create(f util.File, size, start, blocksize int64, volumeLabel string) (*Fil

// write the boot sector
if err := fs.writeBootSector(); err != nil {
return nil, fmt.Errorf("failed to write the boot sector: %v", err)
return nil, fmt.Errorf("failed to write the boot sector: %w", err)
}

// write the fsis
if err := fs.writeFsis(); err != nil {
return nil, fmt.Errorf("failed to write the file system information sector: %v", err)
return nil, fmt.Errorf("failed to write the file system information sector: %w", err)
}

// write the FAT tables
if err := fs.writeFat(); err != nil {
return nil, fmt.Errorf("failed to write the file allocation table: %v", err)
return nil, fmt.Errorf("failed to write the file allocation table: %w", err)
}

// create root directory
Expand All @@ -279,7 +279,7 @@ func Create(f util.File, size, start, blocksize int64, volumeLabel string) (*Fil
// zero out the root directory cluster
written, err := f.WriteAt(tmpb, clusterStart)
if err != nil {
return nil, fmt.Errorf("failed to zero out root directory: %v", err)
return nil, fmt.Errorf("failed to zero out root directory: %w", err)
}
if written != len(tmpb) || written != fs.bytesPerCluster {
return nil, fmt.Errorf("incomplete zero out of root directory, wrote %d bytes instead of expected %d for cluster size %d", written, len(tmpb), fs.bytesPerCluster)
Expand All @@ -296,13 +296,13 @@ func Create(f util.File, size, start, blocksize int64, volumeLabel string) (*Fil
// write the root directory entries to disk
err = fs.writeDirectoryEntries(rootDir)
if err != nil {
return nil, fmt.Errorf("error writing root directory to disk: %v", err)
return nil, fmt.Errorf("error writing root directory to disk: %w", err)
}

// set the volume label
err = fs.SetLabel(volumeLabel)
if err != nil {
return nil, fmt.Errorf("failed to set volume label to '%s': %v", volumeLabel, err)
return nil, fmt.Errorf("failed to set volume label to '%s': %w", volumeLabel, err)
}

return fs, nil
Expand Down Expand Up @@ -341,15 +341,15 @@ func Read(file util.File, size, start, blocksize int64) (*FileSystem, error) {
bsb := make([]byte, SectorSize512)
n, err := file.ReadAt(bsb, start)
if err != nil {
return nil, fmt.Errorf("could not read bytes from file: %v", err)
return nil, fmt.Errorf("could not read bytes from file: %w", err)
}
if uint16(n) < uint16(SectorSize512) {
return nil, fmt.Errorf("only could read %d bytes from file", n)
}
bs, err := msDosBootSectorFromBytes(bsb)

if err != nil {
return nil, fmt.Errorf("error reading MS-DOS Boot Sector: %v", err)
return nil, fmt.Errorf("error reading MS-DOS Boot Sector: %w", err)
}

sectorsPerFat := bs.biosParameterBlock.sectorsPerFat
Expand All @@ -362,14 +362,14 @@ func Read(file util.File, size, start, blocksize int64) (*FileSystem, error) {
fsisBytes := make([]byte, 512)
read, err := file.ReadAt(fsisBytes, int64(bs.biosParameterBlock.fsInformationSector)*blocksize+start)
if err != nil {
return nil, fmt.Errorf("unable to read bytes for FSInformationSector: %v", err)
return nil, fmt.Errorf("unable to read bytes for FSInformationSector: %w", err)
}
if read != 512 {
return nil, fmt.Errorf("read %d bytes instead of expected %d for FS Information Sector", read, 512)
}
fsis, err := fsInformationSectorFromBytes(fsisBytes)
if err != nil {
return nil, fmt.Errorf("error reading FileSystem Information Sector: %v", err)
return nil, fmt.Errorf("error reading FileSystem Information Sector: %w", err)
}

b := make([]byte, fatSize)
Expand Down Expand Up @@ -406,13 +406,13 @@ func (fs *FileSystem) writeBootSector() error {

b, err := fs.bootSector.toBytes()
if err != nil {
return fmt.Errorf("error converting MS-DOS Boot Sector to bytes: %v", err)
return fmt.Errorf("error converting MS-DOS Boot Sector to bytes: %w", err)
}

// write main boot sector
count, err := fs.file.WriteAt(b, 0+fs.start)
if err != nil {
return fmt.Errorf("error writing MS-DOS Boot Sector to disk: %v", err)
return fmt.Errorf("error writing MS-DOS Boot Sector to disk: %w", err)
}
if count != int(SectorSize512) {
return fmt.Errorf("wrote %d bytes of MS-DOS Boot Sector to disk instead of expected %d", count, SectorSize512)
Expand All @@ -422,7 +422,7 @@ func (fs *FileSystem) writeBootSector() error {
if fs.bootSector.biosParameterBlock.backupBootSector > 0 {
count, err = fs.file.WriteAt(b, int64(fs.bootSector.biosParameterBlock.backupBootSector)*int64(SectorSize512)+fs.start)
if err != nil {
return fmt.Errorf("error writing MS-DOS Boot Sector to disk: %v", err)
return fmt.Errorf("error writing MS-DOS Boot Sector to disk: %w", err)
}
if count != int(SectorSize512) {
return fmt.Errorf("wrote %d bytes of MS-DOS Boot Sector to disk instead of expected %d", count, SectorSize512)
Expand All @@ -440,12 +440,12 @@ func (fs *FileSystem) writeFsis() error {
fsisBytes := fs.fsis.toBytes()

if _, err := fs.file.WriteAt(fsisBytes, fsisPrimary+fs.start); err != nil {
return fmt.Errorf("unable to write primary Fsis: %v", err)
return fmt.Errorf("unable to write primary Fsis: %w", err)
}

if backupBootSector > 0 {
if _, err := fs.file.WriteAt(fsisBytes, int64(backupBootSector+1)*int64(SectorSize512)+fs.start); err != nil {
return fmt.Errorf("unable to write backup Fsis: %v", err)
return fmt.Errorf("unable to write backup Fsis: %w", err)
}
}

Expand All @@ -460,11 +460,11 @@ func (fs *FileSystem) writeFat() error {
fatBytes := fs.table.bytes()

if _, err := fs.file.WriteAt(fatBytes, int64(fatPrimaryStart)+fs.start); err != nil {
return fmt.Errorf("unable to write primary FAT table: %v", err)
return fmt.Errorf("unable to write primary FAT table: %w", err)
}

if _, err := fs.file.WriteAt(fatBytes, int64(fatSecondaryStart)+fs.start); err != nil {
return fmt.Errorf("unable to write backup FAT table: %v", err)
return fmt.Errorf("unable to write backup FAT table: %w", err)
}

return nil
Expand Down Expand Up @@ -493,7 +493,7 @@ func (fs *FileSystem) Mkdir(p string) error {
func (fs *FileSystem) ReadDir(p string) ([]os.FileInfo, error) {
_, entries, err := fs.readDirWithMkdir(p, false)
if err != nil {
return nil, fmt.Errorf("error reading directory %s: %v", p, err)
return nil, fmt.Errorf("error reading directory %s: %w", p, err)
}
// once we have made it here, looping is done. We have found the final entry
// we need to return all of the file info
Expand Down Expand Up @@ -542,7 +542,7 @@ func (fs *FileSystem) OpenFile(p string, flag int) (filesystem.File, error) {
// get the directory entries
parentDir, entries, err := fs.readDirWithMkdir(dir, false)
if err != nil {
return nil, fmt.Errorf("could not read directory entries for %s", dir)
return nil, fmt.Errorf("could not read directory entries for %s: %w", dir, err)
}
// we now know that the directory exists, see if the file exists
var targetEntry *directoryEntry
Expand Down Expand Up @@ -571,12 +571,12 @@ func (fs *FileSystem) OpenFile(p string, flag int) (filesystem.File, error) {
// else create it
targetEntry, err = fs.mkFile(parentDir, filename)
if err != nil {
return nil, fmt.Errorf("failed to create file %s: %v", p, err)
return nil, fmt.Errorf("failed to create file %s: %w", p, err)
}
// write the directory entries to disk
err = fs.writeDirectoryEntries(parentDir)
if err != nil {
return nil, fmt.Errorf("error writing directory file %s to disk: %v", p, err)
return nil, fmt.Errorf("error writing directory file %s to disk: %w", p, err)
}
}
offset := int64(0)
Expand All @@ -587,10 +587,10 @@ func (fs *FileSystem) OpenFile(p string, flag int) (filesystem.File, error) {
targetEntry.fileSize = 0
// we should not need to change the parent, because it is all pointers
if err := fs.writeDirectoryEntries(parentDir); err != nil {
return nil, fmt.Errorf("error writing directory file %s to disk: %v", p, err)
return nil, fmt.Errorf("error writing directory file %s to disk: %w", p, err)
}
if _, err := fs.allocateSpace(1, targetEntry.clusterLocation); err != nil {
return nil, fmt.Errorf("unable to resize cluster list: %v", err)
return nil, fmt.Errorf("unable to resize cluster list: %w", err)
}
}
if flag&os.O_APPEND == os.O_APPEND {
Expand Down Expand Up @@ -651,13 +651,13 @@ func (fs *FileSystem) SetLabel(volumeLabel string) error {

// write the boot sector
if err := fs.writeBootSector(); err != nil {
return fmt.Errorf("failed to write the boot sector")
return fmt.Errorf("failed to write the boot sector: %w", err)
}

// locate the filesystem root directory or create it
rootDir, dirEntries, err := fs.readDirWithMkdir("/", false)
if err != nil {
return fmt.Errorf("failed to locate root directory: %v", err)
return fmt.Errorf("failed to locate root directory: %w", err)
}

// locate the label entry, it may not exist
Expand All @@ -675,14 +675,14 @@ func (fs *FileSystem) SetLabel(volumeLabel string) error {
} else {
_, err = fs.mkLabel(rootDir, volumeLabel)
if err != nil {
return fmt.Errorf("failed to create volume label root directory entry '%s': %v", volumeLabel, err)
return fmt.Errorf("failed to create volume label root directory entry '%s': %w", volumeLabel, err)
}
}

// write the root directory entries to disk
err = fs.writeDirectoryEntries(rootDir)
if err != nil {
return fmt.Errorf("failed to save the root directory to disk: %v", err)
return fmt.Errorf("failed to save the root directory to disk: %w", err)
}

return nil
Expand Down Expand Up @@ -723,7 +723,7 @@ func (fs *FileSystem) getClusterList(firstCluster uint32) ([]uint32, error) {
func (fs *FileSystem) readDirectory(dir *Directory) ([]*directoryEntry, error) {
clusterList, err := fs.getClusterList(dir.clusterLocation)
if err != nil {
return nil, fmt.Errorf("could not read cluster list: %v", err)
return nil, fmt.Errorf("could not read cluster list: %w", err)
}
// read the data from all of the cluster entries in the list
byteCount := len(clusterList) * fs.bytesPerCluster
Expand All @@ -749,7 +749,7 @@ func (fs *FileSystem) mkSubdir(parent *Directory, name string) (*directoryEntry,
// get a cluster chain for the file
clusters, err := fs.allocateSpace(1, 0)
if err != nil {
return nil, fmt.Errorf("could not allocate disk space for file %s: %v", name, err)
return nil, fmt.Errorf("could not allocate disk space for file %s: %w", name, err)
}
// create a directory entry for the file
return parent.createEntry(name, clusters[0], true)
Expand All @@ -759,19 +759,19 @@ func (fs *FileSystem) writeDirectoryEntries(dir *Directory) error {
// we need to save the entries of theparent
b, err := dir.entriesToBytes(fs.bytesPerCluster)
if err != nil {
return fmt.Errorf("could not create a valid byte stream for a FAT32 Entries: %v", err)
return fmt.Errorf("could not create a valid byte stream for a FAT32 Entries: %w", err)
}
// now have to expand with zeros to the a multiple of cluster lengths
// how many clusters do we need, how many do we have?
clusterList, err := fs.getClusterList(dir.clusterLocation)
if err != nil {
return fmt.Errorf("unable to get clusters for directory: %v", err)
return fmt.Errorf("unable to get clusters for directory: %w", err)
}

if len(b) > len(clusterList)*fs.bytesPerCluster {
clusters, err := fs.allocateSpace(uint64(len(b)), clusterList[0])
if err != nil {
return fmt.Errorf("unable to allocate space for directory entries: %v", err)
return fmt.Errorf("unable to allocate space for directory entries: %w", err)
}
clusterList = clusters
}
Expand All @@ -783,7 +783,7 @@ func (fs *FileSystem) writeDirectoryEntries(dir *Directory) error {
bStart := i * fs.bytesPerCluster
written, err := fs.file.WriteAt(b[bStart:bStart+fs.bytesPerCluster], clusterStart)
if err != nil {
return fmt.Errorf("error writing directory entries: %v", err)
return fmt.Errorf("error writing directory entries: %w", err)
}
if written != fs.bytesPerCluster {
return fmt.Errorf("wrote %d bytes to cluster %d instead of expected %d", written, cluster, fs.bytesPerCluster)
Expand All @@ -797,7 +797,7 @@ func (fs *FileSystem) mkFile(parent *Directory, name string) (*directoryEntry, e
// get a cluster chain for the file
clusters, err := fs.allocateSpace(1, 0)
if err != nil {
return nil, fmt.Errorf("could not allocate disk space for directory %s: %v", name, err)
return nil, fmt.Errorf("could not allocate disk space for directory %s: %w", name, err)
}
// create a directory entry for the file
return parent.createEntry(name, clusters[0], false)
Expand Down Expand Up @@ -829,7 +829,7 @@ func (fs *FileSystem) readDirWithMkdir(p string, doMake bool) (*Directory, []*di
}
entries, err = fs.readDirectory(currentDir)
if err != nil {
return nil, nil, fmt.Errorf("failed to read directory %s", "/")
return nil, nil, fmt.Errorf("failed to read directory %s: %w", "/", err)
}
for i, subp := range paths {
// do we have an entry whose name is the same as this name?
Expand Down Expand Up @@ -860,7 +860,7 @@ func (fs *FileSystem) readDirWithMkdir(p string, doMake bool) (*Directory, []*di
var subdirEntry *directoryEntry
subdirEntry, err = fs.mkSubdir(currentDir, subp)
if err != nil {
return nil, nil, fmt.Errorf("failed to create subdirectory %s", "/"+strings.Join(paths[0:i+1], "/"))
return nil, nil, fmt.Errorf("failed to create subdirectory %s: %w", "/"+strings.Join(paths[0:i+1], "/"), err)
}
currentDir.modifyTime = subdirEntry.createTime
// make a basic entry for the new subdir
Expand Down Expand Up @@ -893,12 +893,12 @@ func (fs *FileSystem) readDirWithMkdir(p string, doMake bool) (*Directory, []*di
// write the new directory entries to disk
err = fs.writeDirectoryEntries(dir)
if err != nil {
return nil, nil, fmt.Errorf("error writing new directory entries to disk: %v", err)
return nil, nil, fmt.Errorf("error writing new directory entries to disk: %w", err)
}
// write the parent directory entries to disk
err = fs.writeDirectoryEntries(currentDir)
if err != nil {
return nil, nil, fmt.Errorf("error writing directory entries to disk: %v", err)
return nil, nil, fmt.Errorf("error writing directory entries to disk: %w", err)
}
// save where we are to search next
currentDir = &Directory{
Expand All @@ -911,7 +911,7 @@ func (fs *FileSystem) readDirWithMkdir(p string, doMake bool) (*Directory, []*di
// get all of the entries in this directory
entries, err = fs.readDirectory(currentDir)
if err != nil {
return nil, nil, fmt.Errorf("failed to read directory %s", "/"+strings.Join(paths[0:i+1], "/"))
return nil, nil, fmt.Errorf("failed to read directory %s: %w", "/"+strings.Join(paths[0:i+1], "/"), err)
}
}
// once we have made it here, looping is done; we have found the final entry
Expand Down Expand Up @@ -951,7 +951,7 @@ func (fs *FileSystem) allocateSpace(size uint64, previous uint32) ([]uint32, err
if previous >= 2 {
clusters, err = fs.getClusterList(previous)
if err != nil {
return nil, fmt.Errorf("unable to get cluster list: %v", err)
return nil, fmt.Errorf("unable to get cluster list: %w", err)
}
originalClusterCount := len(clusters)
extraClusterCount = count - originalClusterCount
Expand Down Expand Up @@ -1030,12 +1030,12 @@ func (fs *FileSystem) allocateSpace(size uint64, previous uint32) ([]uint32, err
// update the FSIS
fs.fsis.lastAllocatedCluster = lastAllocatedCluster
if err := fs.writeFsis(); err != nil {
return nil, fmt.Errorf("failed to write the file system information sector: %v", err)
return nil, fmt.Errorf("failed to write the file system information sector: %w", err)
}

// write the FAT tables
if err := fs.writeFat(); err != nil {
return nil, fmt.Errorf("failed to write the file allocation table: %v", err)
return nil, fmt.Errorf("failed to write the file allocation table: %w", err)
}

// return all of the clusters
Expand Down

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