diff options
Diffstat (limited to 'vendor/github.com/Microsoft/hcsshim/internal/wclayer/baselayer.go')
-rw-r--r-- | vendor/github.com/Microsoft/hcsshim/internal/wclayer/baselayer.go | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/vendor/github.com/Microsoft/hcsshim/internal/wclayer/baselayer.go b/vendor/github.com/Microsoft/hcsshim/internal/wclayer/baselayer.go new file mode 100644 index 000000000..5784241df --- /dev/null +++ b/vendor/github.com/Microsoft/hcsshim/internal/wclayer/baselayer.go @@ -0,0 +1,173 @@ +package wclayer + +import ( + "errors" + "os" + "path/filepath" + "syscall" + + "github.com/Microsoft/go-winio" + "github.com/Microsoft/hcsshim/internal/hcserror" + "github.com/Microsoft/hcsshim/internal/safefile" +) + +type baseLayerWriter struct { + root *os.File + f *os.File + bw *winio.BackupFileWriter + err error + hasUtilityVM bool + dirInfo []dirInfo +} + +type dirInfo struct { + path string + fileInfo winio.FileBasicInfo +} + +// reapplyDirectoryTimes reapplies directory modification, creation, etc. times +// after processing of the directory tree has completed. The times are expected +// to be ordered such that parent directories come before child directories. +func reapplyDirectoryTimes(root *os.File, dis []dirInfo) error { + for i := range dis { + di := &dis[len(dis)-i-1] // reverse order: process child directories first + f, err := safefile.OpenRelative(di.path, root, syscall.GENERIC_READ|syscall.GENERIC_WRITE, syscall.FILE_SHARE_READ, safefile.FILE_OPEN, safefile.FILE_DIRECTORY_FILE) + if err != nil { + return err + } + + err = winio.SetFileBasicInfo(f, &di.fileInfo) + f.Close() + if err != nil { + return err + } + } + return nil +} + +func (w *baseLayerWriter) closeCurrentFile() error { + if w.f != nil { + err := w.bw.Close() + err2 := w.f.Close() + w.f = nil + w.bw = nil + if err != nil { + return err + } + if err2 != nil { + return err2 + } + } + return nil +} + +func (w *baseLayerWriter) Add(name string, fileInfo *winio.FileBasicInfo) (err error) { + defer func() { + if err != nil { + w.err = err + } + }() + + err = w.closeCurrentFile() + if err != nil { + return err + } + + if filepath.ToSlash(name) == `UtilityVM/Files` { + w.hasUtilityVM = true + } + + var f *os.File + defer func() { + if f != nil { + f.Close() + } + }() + + extraFlags := uint32(0) + if fileInfo.FileAttributes&syscall.FILE_ATTRIBUTE_DIRECTORY != 0 { + extraFlags |= safefile.FILE_DIRECTORY_FILE + if fileInfo.FileAttributes&syscall.FILE_ATTRIBUTE_REPARSE_POINT == 0 { + w.dirInfo = append(w.dirInfo, dirInfo{name, *fileInfo}) + } + } + + mode := uint32(syscall.GENERIC_READ | syscall.GENERIC_WRITE | winio.WRITE_DAC | winio.WRITE_OWNER | winio.ACCESS_SYSTEM_SECURITY) + f, err = safefile.OpenRelative(name, w.root, mode, syscall.FILE_SHARE_READ, safefile.FILE_CREATE, extraFlags) + if err != nil { + return hcserror.New(err, "Failed to safefile.OpenRelative", name) + } + + err = winio.SetFileBasicInfo(f, fileInfo) + if err != nil { + return hcserror.New(err, "Failed to SetFileBasicInfo", name) + } + + w.f = f + w.bw = winio.NewBackupFileWriter(f, true) + f = nil + return nil +} + +func (w *baseLayerWriter) AddLink(name string, target string) (err error) { + defer func() { + if err != nil { + w.err = err + } + }() + + err = w.closeCurrentFile() + if err != nil { + return err + } + + return safefile.LinkRelative(target, w.root, name, w.root) +} + +func (w *baseLayerWriter) Remove(name string) error { + return errors.New("base layer cannot have tombstones") +} + +func (w *baseLayerWriter) Write(b []byte) (int, error) { + n, err := w.bw.Write(b) + if err != nil { + w.err = err + } + return n, err +} + +func (w *baseLayerWriter) Close() error { + defer func() { + w.root.Close() + w.root = nil + }() + err := w.closeCurrentFile() + if err != nil { + return err + } + if w.err == nil { + // Restore the file times of all the directories, since they may have + // been modified by creating child directories. + err = reapplyDirectoryTimes(w.root, w.dirInfo) + if err != nil { + return err + } + + err = ProcessBaseLayer(w.root.Name()) + if err != nil { + return err + } + + if w.hasUtilityVM { + err := safefile.EnsureNotReparsePointRelative("UtilityVM", w.root) + if err != nil { + return err + } + err = ProcessUtilityVMImage(filepath.Join(w.root.Name(), "UtilityVM")) + if err != nil { + return err + } + } + } + return w.err +} |