diff options
Diffstat (limited to 'vendor/github.com/containerd/continuity/fs/path.go')
-rw-r--r-- | vendor/github.com/containerd/continuity/fs/path.go | 311 |
1 files changed, 0 insertions, 311 deletions
diff --git a/vendor/github.com/containerd/continuity/fs/path.go b/vendor/github.com/containerd/continuity/fs/path.go deleted file mode 100644 index c26be7989..000000000 --- a/vendor/github.com/containerd/continuity/fs/path.go +++ /dev/null @@ -1,311 +0,0 @@ -/* - Copyright The containerd Authors. - - Licensed under the Apache License, Version 2.0 (the "License"); - you may not use this file except in compliance with the License. - You may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - - Unless required by applicable law or agreed to in writing, software - distributed under the License is distributed on an "AS IS" BASIS, - WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - See the License for the specific language governing permissions and - limitations under the License. -*/ - -package fs - -import ( - "bytes" - "context" - "io" - "os" - "path/filepath" - - "github.com/pkg/errors" -) - -var ( - errTooManyLinks = errors.New("too many links") -) - -type currentPath struct { - path string - f os.FileInfo - fullPath string -} - -func pathChange(lower, upper *currentPath) (ChangeKind, string) { - if lower == nil { - if upper == nil { - panic("cannot compare nil paths") - } - return ChangeKindAdd, upper.path - } - if upper == nil { - return ChangeKindDelete, lower.path - } - - switch i := directoryCompare(lower.path, upper.path); { - case i < 0: - // File in lower that is not in upper - return ChangeKindDelete, lower.path - case i > 0: - // File in upper that is not in lower - return ChangeKindAdd, upper.path - default: - return ChangeKindModify, upper.path - } -} - -func directoryCompare(a, b string) int { - l := len(a) - if len(b) < l { - l = len(b) - } - for i := 0; i < l; i++ { - c1, c2 := a[i], b[i] - if c1 == filepath.Separator { - c1 = byte(0) - } - if c2 == filepath.Separator { - c2 = byte(0) - } - if c1 < c2 { - return -1 - } - if c1 > c2 { - return +1 - } - } - if len(a) < len(b) { - return -1 - } - if len(a) > len(b) { - return +1 - } - return 0 -} - -func sameFile(f1, f2 *currentPath) (bool, error) { - if os.SameFile(f1.f, f2.f) { - return true, nil - } - - equalStat, err := compareSysStat(f1.f.Sys(), f2.f.Sys()) - if err != nil || !equalStat { - return equalStat, err - } - - if eq, err := compareCapabilities(f1.fullPath, f2.fullPath); err != nil || !eq { - return eq, err - } - - // If not a directory also check size, modtime, and content - if !f1.f.IsDir() { - if f1.f.Size() != f2.f.Size() { - return false, nil - } - t1 := f1.f.ModTime() - t2 := f2.f.ModTime() - - if t1.Unix() != t2.Unix() { - return false, nil - } - - // If the timestamp may have been truncated in both of the - // files, check content of file to determine difference - if t1.Nanosecond() == 0 && t2.Nanosecond() == 0 { - if (f1.f.Mode() & os.ModeSymlink) == os.ModeSymlink { - return compareSymlinkTarget(f1.fullPath, f2.fullPath) - } - if f1.f.Size() == 0 { // if file sizes are zero length, the files are the same by definition - return true, nil - } - return compareFileContent(f1.fullPath, f2.fullPath) - } else if t1.Nanosecond() != t2.Nanosecond() { - return false, nil - } - } - - return true, nil -} - -func compareSymlinkTarget(p1, p2 string) (bool, error) { - t1, err := os.Readlink(p1) - if err != nil { - return false, err - } - t2, err := os.Readlink(p2) - if err != nil { - return false, err - } - return t1 == t2, nil -} - -const compareChuckSize = 32 * 1024 - -// compareFileContent compares the content of 2 same sized files -// by comparing each byte. -func compareFileContent(p1, p2 string) (bool, error) { - f1, err := os.Open(p1) - if err != nil { - return false, err - } - defer f1.Close() - f2, err := os.Open(p2) - if err != nil { - return false, err - } - defer f2.Close() - - b1 := make([]byte, compareChuckSize) - b2 := make([]byte, compareChuckSize) - for { - n1, err1 := f1.Read(b1) - if err1 != nil && err1 != io.EOF { - return false, err1 - } - n2, err2 := f2.Read(b2) - if err2 != nil && err2 != io.EOF { - return false, err2 - } - if n1 != n2 || !bytes.Equal(b1[:n1], b2[:n2]) { - return false, nil - } - if err1 == io.EOF && err2 == io.EOF { - return true, nil - } - } -} - -func pathWalk(ctx context.Context, root string, pathC chan<- *currentPath) error { - return filepath.Walk(root, func(path string, f os.FileInfo, err error) error { - if err != nil { - return err - } - - // Rebase path - path, err = filepath.Rel(root, path) - if err != nil { - return err - } - - path = filepath.Join(string(os.PathSeparator), path) - - // Skip root - if path == string(os.PathSeparator) { - return nil - } - - p := ¤tPath{ - path: path, - f: f, - fullPath: filepath.Join(root, path), - } - - select { - case <-ctx.Done(): - return ctx.Err() - case pathC <- p: - return nil - } - }) -} - -func nextPath(ctx context.Context, pathC <-chan *currentPath) (*currentPath, error) { - select { - case <-ctx.Done(): - return nil, ctx.Err() - case p := <-pathC: - return p, nil - } -} - -// RootPath joins a path with a root, evaluating and bounding any -// symlink to the root directory. -func RootPath(root, path string) (string, error) { - if path == "" { - return root, nil - } - var linksWalked int // to protect against cycles - for { - i := linksWalked - newpath, err := walkLinks(root, path, &linksWalked) - if err != nil { - return "", err - } - path = newpath - if i == linksWalked { - newpath = filepath.Join("/", newpath) - if path == newpath { - return filepath.Join(root, newpath), nil - } - path = newpath - } - } -} - -func walkLink(root, path string, linksWalked *int) (newpath string, islink bool, err error) { - if *linksWalked > 255 { - return "", false, errTooManyLinks - } - - path = filepath.Join("/", path) - if path == "/" { - return path, false, nil - } - realPath := filepath.Join(root, path) - - fi, err := os.Lstat(realPath) - if err != nil { - // If path does not yet exist, treat as non-symlink - if os.IsNotExist(err) { - return path, false, nil - } - return "", false, err - } - if fi.Mode()&os.ModeSymlink == 0 { - return path, false, nil - } - newpath, err = os.Readlink(realPath) - if err != nil { - return "", false, err - } - *linksWalked++ - return newpath, true, nil -} - -func walkLinks(root, path string, linksWalked *int) (string, error) { - switch dir, file := filepath.Split(path); { - case dir == "": - newpath, _, err := walkLink(root, file, linksWalked) - return newpath, err - case file == "": - if os.IsPathSeparator(dir[len(dir)-1]) { - if dir == "/" { - return dir, nil - } - return walkLinks(root, dir[:len(dir)-1], linksWalked) - } - newpath, _, err := walkLink(root, dir, linksWalked) - return newpath, err - default: - newdir, err := walkLinks(root, dir, linksWalked) - if err != nil { - return "", err - } - newpath, islink, err := walkLink(root, filepath.Join(newdir, file), linksWalked) - if err != nil { - return "", err - } - if !islink { - return newpath, nil - } - if filepath.IsAbs(newpath) { - return newpath, nil - } - return filepath.Join(newdir, newpath), nil - } -} |