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Diffstat (limited to 'vendor/github.com/containerd/continuity/sysx/file_posix.go')
-rw-r--r--vendor/github.com/containerd/continuity/sysx/file_posix.go128
1 files changed, 0 insertions, 128 deletions
diff --git a/vendor/github.com/containerd/continuity/sysx/file_posix.go b/vendor/github.com/containerd/continuity/sysx/file_posix.go
deleted file mode 100644
index e28f3a1b5..000000000
--- a/vendor/github.com/containerd/continuity/sysx/file_posix.go
+++ /dev/null
@@ -1,128 +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 sysx
-
-import (
- "os"
- "path/filepath"
-
- "github.com/containerd/continuity/syscallx"
-)
-
-// Readlink returns the destination of the named symbolic link.
-// If there is an error, it will be of type *PathError.
-func Readlink(name string) (string, error) {
- for len := 128; ; len *= 2 {
- b := make([]byte, len)
- n, e := fixCount(syscallx.Readlink(fixLongPath(name), b))
- if e != nil {
- return "", &os.PathError{Op: "readlink", Path: name, Err: e}
- }
- if n < len {
- return string(b[0:n]), nil
- }
- }
-}
-
-// Many functions in package syscall return a count of -1 instead of 0.
-// Using fixCount(call()) instead of call() corrects the count.
-func fixCount(n int, err error) (int, error) {
- if n < 0 {
- n = 0
- }
- return n, err
-}
-
-// fixLongPath returns the extended-length (\\?\-prefixed) form of
-// path when needed, in order to avoid the default 260 character file
-// path limit imposed by Windows. If path is not easily converted to
-// the extended-length form (for example, if path is a relative path
-// or contains .. elements), or is short enough, fixLongPath returns
-// path unmodified.
-//
-// See https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx#maxpath
-func fixLongPath(path string) string {
- // Do nothing (and don't allocate) if the path is "short".
- // Empirically (at least on the Windows Server 2013 builder),
- // the kernel is arbitrarily okay with < 248 bytes. That
- // matches what the docs above say:
- // "When using an API to create a directory, the specified
- // path cannot be so long that you cannot append an 8.3 file
- // name (that is, the directory name cannot exceed MAX_PATH
- // minus 12)." Since MAX_PATH is 260, 260 - 12 = 248.
- //
- // The MSDN docs appear to say that a normal path that is 248 bytes long
- // will work; empirically the path must be less then 248 bytes long.
- if len(path) < 248 {
- // Don't fix. (This is how Go 1.7 and earlier worked,
- // not automatically generating the \\?\ form)
- return path
- }
-
- // The extended form begins with \\?\, as in
- // \\?\c:\windows\foo.txt or \\?\UNC\server\share\foo.txt.
- // The extended form disables evaluation of . and .. path
- // elements and disables the interpretation of / as equivalent
- // to \. The conversion here rewrites / to \ and elides
- // . elements as well as trailing or duplicate separators. For
- // simplicity it avoids the conversion entirely for relative
- // paths or paths containing .. elements. For now,
- // \\server\share paths are not converted to
- // \\?\UNC\server\share paths because the rules for doing so
- // are less well-specified.
- if len(path) >= 2 && path[:2] == `\\` {
- // Don't canonicalize UNC paths.
- return path
- }
- if !filepath.IsAbs(path) {
- // Relative path
- return path
- }
-
- const prefix = `\\?`
-
- pathbuf := make([]byte, len(prefix)+len(path)+len(`\`))
- copy(pathbuf, prefix)
- n := len(path)
- r, w := 0, len(prefix)
- for r < n {
- switch {
- case os.IsPathSeparator(path[r]):
- // empty block
- r++
- case path[r] == '.' && (r+1 == n || os.IsPathSeparator(path[r+1])):
- // /./
- r++
- case r+1 < n && path[r] == '.' && path[r+1] == '.' && (r+2 == n || os.IsPathSeparator(path[r+2])):
- // /../ is currently unhandled
- return path
- default:
- pathbuf[w] = '\\'
- w++
- for ; r < n && !os.IsPathSeparator(path[r]); r++ {
- pathbuf[w] = path[r]
- w++
- }
- }
- }
- // A drive's root directory needs a trailing \
- if w == len(`\\?\c:`) {
- pathbuf[w] = '\\'
- w++
- }
- return string(pathbuf[:w])
-}