diff options
Diffstat (limited to 'vendor/github.com/spf13/afero/unionFile.go')
-rw-r--r-- | vendor/github.com/spf13/afero/unionFile.go | 189 |
1 files changed, 110 insertions, 79 deletions
diff --git a/vendor/github.com/spf13/afero/unionFile.go b/vendor/github.com/spf13/afero/unionFile.go index 99f9e5db..1e78f7d1 100644 --- a/vendor/github.com/spf13/afero/unionFile.go +++ b/vendor/github.com/spf13/afero/unionFile.go @@ -21,32 +21,33 @@ import ( // successful read in the overlay will move the cursor position in the base layer // by the number of bytes read. type UnionFile struct { - base File - layer File - off int - files []os.FileInfo + Base File + Layer File + Merger DirsMerger + off int + files []os.FileInfo } func (f *UnionFile) Close() error { // first close base, so we have a newer timestamp in the overlay. If we'd close // the overlay first, we'd get a cacheStale the next time we access this file // -> cache would be useless ;-) - if f.base != nil { - f.base.Close() + if f.Base != nil { + f.Base.Close() } - if f.layer != nil { - return f.layer.Close() + if f.Layer != nil { + return f.Layer.Close() } return BADFD } func (f *UnionFile) Read(s []byte) (int, error) { - if f.layer != nil { - n, err := f.layer.Read(s) - if (err == nil || err == io.EOF) && f.base != nil { + if f.Layer != nil { + n, err := f.Layer.Read(s) + if (err == nil || err == io.EOF) && f.Base != nil { // advance the file position also in the base file, the next // call may be a write at this position (or a seek with SEEK_CUR) - if _, seekErr := f.base.Seek(int64(n), os.SEEK_CUR); seekErr != nil { + if _, seekErr := f.Base.Seek(int64(n), os.SEEK_CUR); seekErr != nil { // only overwrite err in case the seek fails: we need to // report an eventual io.EOF to the caller err = seekErr @@ -54,105 +55,135 @@ func (f *UnionFile) Read(s []byte) (int, error) { } return n, err } - if f.base != nil { - return f.base.Read(s) + if f.Base != nil { + return f.Base.Read(s) } return 0, BADFD } func (f *UnionFile) ReadAt(s []byte, o int64) (int, error) { - if f.layer != nil { - n, err := f.layer.ReadAt(s, o) - if (err == nil || err == io.EOF) && f.base != nil { - _, err = f.base.Seek(o+int64(n), os.SEEK_SET) + if f.Layer != nil { + n, err := f.Layer.ReadAt(s, o) + if (err == nil || err == io.EOF) && f.Base != nil { + _, err = f.Base.Seek(o+int64(n), os.SEEK_SET) } return n, err } - if f.base != nil { - return f.base.ReadAt(s, o) + if f.Base != nil { + return f.Base.ReadAt(s, o) } return 0, BADFD } func (f *UnionFile) Seek(o int64, w int) (pos int64, err error) { - if f.layer != nil { - pos, err = f.layer.Seek(o, w) - if (err == nil || err == io.EOF) && f.base != nil { - _, err = f.base.Seek(o, w) + if f.Layer != nil { + pos, err = f.Layer.Seek(o, w) + if (err == nil || err == io.EOF) && f.Base != nil { + _, err = f.Base.Seek(o, w) } return pos, err } - if f.base != nil { - return f.base.Seek(o, w) + if f.Base != nil { + return f.Base.Seek(o, w) } return 0, BADFD } func (f *UnionFile) Write(s []byte) (n int, err error) { - if f.layer != nil { - n, err = f.layer.Write(s) - if err == nil && f.base != nil { // hmm, do we have fixed size files where a write may hit the EOF mark? - _, err = f.base.Write(s) + if f.Layer != nil { + n, err = f.Layer.Write(s) + if err == nil && f.Base != nil { // hmm, do we have fixed size files where a write may hit the EOF mark? + _, err = f.Base.Write(s) } return n, err } - if f.base != nil { - return f.base.Write(s) + if f.Base != nil { + return f.Base.Write(s) } return 0, BADFD } func (f *UnionFile) WriteAt(s []byte, o int64) (n int, err error) { - if f.layer != nil { - n, err = f.layer.WriteAt(s, o) - if err == nil && f.base != nil { - _, err = f.base.WriteAt(s, o) + if f.Layer != nil { + n, err = f.Layer.WriteAt(s, o) + if err == nil && f.Base != nil { + _, err = f.Base.WriteAt(s, o) } return n, err } - if f.base != nil { - return f.base.WriteAt(s, o) + if f.Base != nil { + return f.Base.WriteAt(s, o) } return 0, BADFD } func (f *UnionFile) Name() string { - if f.layer != nil { - return f.layer.Name() + if f.Layer != nil { + return f.Layer.Name() } - return f.base.Name() + return f.Base.Name() +} + +// DirsMerger is how UnionFile weaves two directories together. +// It takes the FileInfo slices from the layer and the base and returns a +// single view. +type DirsMerger func(lofi, bofi []os.FileInfo) ([]os.FileInfo, error) + +var defaultUnionMergeDirsFn = func(lofi, bofi []os.FileInfo) ([]os.FileInfo, error) { + var files = make(map[string]os.FileInfo) + + for _, fi := range lofi { + files[fi.Name()] = fi + } + + for _, fi := range bofi { + if _, exists := files[fi.Name()]; !exists { + files[fi.Name()] = fi + } + } + + rfi := make([]os.FileInfo, len(files)) + + i := 0 + for _, fi := range files { + rfi[i] = fi + i++ + } + + return rfi, nil + } // Readdir will weave the two directories together and // return a single view of the overlayed directories func (f *UnionFile) Readdir(c int) (ofi []os.FileInfo, err error) { + var merge DirsMerger = f.Merger + if merge == nil { + merge = defaultUnionMergeDirsFn + } + if f.off == 0 { - var files = make(map[string]os.FileInfo) - var rfi []os.FileInfo - if f.layer != nil { - rfi, err = f.layer.Readdir(-1) + var lfi []os.FileInfo + if f.Layer != nil { + lfi, err = f.Layer.Readdir(-1) if err != nil { return nil, err } - for _, fi := range rfi { - files[fi.Name()] = fi - } } - if f.base != nil { - rfi, err = f.base.Readdir(-1) + var bfi []os.FileInfo + if f.Base != nil { + bfi, err = f.Base.Readdir(-1) if err != nil { return nil, err } - for _, fi := range rfi { - if _, exists := files[fi.Name()]; !exists { - files[fi.Name()] = fi - } - } + } - for _, fi := range files { - f.files = append(f.files, fi) + merged, err := merge(lfi, bfi) + if err != nil { + return nil, err } + f.files = append(f.files, merged...) } if c == -1 { return f.files[f.off:], nil @@ -174,53 +205,53 @@ func (f *UnionFile) Readdirnames(c int) ([]string, error) { } func (f *UnionFile) Stat() (os.FileInfo, error) { - if f.layer != nil { - return f.layer.Stat() + if f.Layer != nil { + return f.Layer.Stat() } - if f.base != nil { - return f.base.Stat() + if f.Base != nil { + return f.Base.Stat() } return nil, BADFD } func (f *UnionFile) Sync() (err error) { - if f.layer != nil { - err = f.layer.Sync() - if err == nil && f.base != nil { - err = f.base.Sync() + if f.Layer != nil { + err = f.Layer.Sync() + if err == nil && f.Base != nil { + err = f.Base.Sync() } return err } - if f.base != nil { - return f.base.Sync() + if f.Base != nil { + return f.Base.Sync() } return BADFD } func (f *UnionFile) Truncate(s int64) (err error) { - if f.layer != nil { - err = f.layer.Truncate(s) - if err == nil && f.base != nil { - err = f.base.Truncate(s) + if f.Layer != nil { + err = f.Layer.Truncate(s) + if err == nil && f.Base != nil { + err = f.Base.Truncate(s) } return err } - if f.base != nil { - return f.base.Truncate(s) + if f.Base != nil { + return f.Base.Truncate(s) } return BADFD } func (f *UnionFile) WriteString(s string) (n int, err error) { - if f.layer != nil { - n, err = f.layer.WriteString(s) - if err == nil && f.base != nil { - _, err = f.base.WriteString(s) + if f.Layer != nil { + n, err = f.Layer.WriteString(s) + if err == nil && f.Base != nil { + _, err = f.Base.WriteString(s) } return n, err } - if f.base != nil { - return f.base.WriteString(s) + if f.Base != nil { + return f.Base.WriteString(s) } return 0, BADFD } |