From e07681c8ca510455062c223ab1f43840ae8d8b9d Mon Sep 17 00:00:00 2001 From: Brian Goff Date: Thu, 31 May 2018 12:18:02 -0400 Subject: [PATCH] Bump docker commit Signed-off-by: Brian Goff (cherry picked from commit aae1b0e116d0c4ee0e46494864d1540fec22ced3) Signed-off-by: selansen --- libnetwork/libnetwork_test.go | 7 +- libnetwork/vendor.conf | 2 +- .../github.com/docker/docker/errdefs/defs.go | 74 ++++++ .../github.com/docker/docker/errdefs/doc.go | 8 + .../docker/docker/errdefs/helpers.go | 240 ++++++++++++++++++ .../github.com/docker/docker/errdefs/is.go | 114 +++++++++ .../docker/docker/pkg/symlink/fs.go | 144 +++++++++++ .../docker/docker/pkg/symlink/fs_unix.go | 15 ++ .../docker/docker/pkg/symlink/fs_windows.go | 169 ++++++++++++ 9 files changed, 769 insertions(+), 4 deletions(-) create mode 100644 libnetwork/vendor/github.com/docker/docker/errdefs/defs.go create mode 100644 libnetwork/vendor/github.com/docker/docker/errdefs/doc.go create mode 100644 libnetwork/vendor/github.com/docker/docker/errdefs/helpers.go create mode 100644 libnetwork/vendor/github.com/docker/docker/errdefs/is.go create mode 100644 libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs.go create mode 100644 libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs_unix.go create mode 100644 libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs_windows.go diff --git a/libnetwork/libnetwork_test.go b/libnetwork/libnetwork_test.go index 21cfb33c33..e7e0ad5c95 100644 --- a/libnetwork/libnetwork_test.go +++ b/libnetwork/libnetwork_test.go @@ -10,6 +10,7 @@ import ( "sync" "testing" + "github.com/docker/docker/errdefs" "github.com/docker/docker/pkg/plugins" "github.com/docker/docker/pkg/reexec" "github.com/docker/libnetwork" @@ -209,7 +210,7 @@ func TestUnknownDriver(t *testing.T) { t.Fatal("Expected to fail. But instead succeeded") } - if _, ok := err.(types.NotFoundError); !ok { + if errdefs.IsNotFound(err) { t.Fatalf("Did not fail with expected error. Actual error: %v", err) } } @@ -221,7 +222,7 @@ func TestNilRemoteDriver(t *testing.T) { t.Fatal("Expected to fail. But instead succeeded") } - if _, ok := err.(types.NotFoundError); !ok { + if !errdefs.IsNotFound(err) { t.Fatalf("Did not fail with expected error. Actual error: %v", err) } } @@ -1396,7 +1397,7 @@ func TestValidRemoteDriver(t *testing.T) { libnetwork.NetworkOptionGeneric(getEmptyGenericOption())) if err != nil { // Only fail if we could not find the plugin driver - if _, ok := err.(types.NotFoundError); ok { + if errdefs.IsNotFound(err) { t.Fatal(err) } return diff --git a/libnetwork/vendor.conf b/libnetwork/vendor.conf index 5237c5588a..370c66c9a9 100644 --- a/libnetwork/vendor.conf +++ b/libnetwork/vendor.conf @@ -14,8 +14,8 @@ github.com/coreos/go-systemd v17 github.com/coreos/pkg fa29b1d70f0beaddd4c7021607cc3c3be8ce94b8 github.com/deckarep/golang-set ef32fa3046d9f249d399f98ebaf9be944430fd1d -github.com/docker/docker 162ba6016def672690ee4a1f3978368853a1e149 github.com/docker/go-connections 7beb39f0b969b075d1325fecb092faf27fd357b6 +github.com/docker/docker 71cd53e4a197b303c6ba086bd584ffd67a884281 github.com/docker/go-events 9461782956ad83b30282bf90e31fa6a70c255ba9 github.com/docker/go-units 9e638d38cf6977a37a8ea0078f3ee75a7cdb2dd1 github.com/docker/libkv 1d8431073ae03cdaedb198a89722f3aab6d418ef diff --git a/libnetwork/vendor/github.com/docker/docker/errdefs/defs.go b/libnetwork/vendor/github.com/docker/docker/errdefs/defs.go new file mode 100644 index 0000000000..e6a2275b2d --- /dev/null +++ b/libnetwork/vendor/github.com/docker/docker/errdefs/defs.go @@ -0,0 +1,74 @@ +package errdefs // import "github.com/docker/docker/errdefs" + +// ErrNotFound signals that the requested object doesn't exist +type ErrNotFound interface { + NotFound() +} + +// ErrInvalidParameter signals that the user input is invalid +type ErrInvalidParameter interface { + InvalidParameter() +} + +// ErrConflict signals that some internal state conflicts with the requested action and can't be performed. +// A change in state should be able to clear this error. +type ErrConflict interface { + Conflict() +} + +// ErrUnauthorized is used to signify that the user is not authorized to perform a specific action +type ErrUnauthorized interface { + Unauthorized() +} + +// ErrUnavailable signals that the requested action/subsystem is not available. +type ErrUnavailable interface { + Unavailable() +} + +// ErrForbidden signals that the requested action cannot be performed under any circumstances. +// When a ErrForbidden is returned, the caller should never retry the action. +type ErrForbidden interface { + Forbidden() +} + +// ErrSystem signals that some internal error occurred. +// An example of this would be a failed mount request. +type ErrSystem interface { + System() +} + +// ErrNotModified signals that an action can't be performed because it's already in the desired state +type ErrNotModified interface { + NotModified() +} + +// ErrAlreadyExists is a special case of ErrConflict which signals that the desired object already exists +type ErrAlreadyExists interface { + AlreadyExists() +} + +// ErrNotImplemented signals that the requested action/feature is not implemented on the system as configured. +type ErrNotImplemented interface { + NotImplemented() +} + +// ErrUnknown signals that the kind of error that occurred is not known. +type ErrUnknown interface { + Unknown() +} + +// ErrCancelled signals that the action was cancelled. +type ErrCancelled interface { + Cancelled() +} + +// ErrDeadline signals that the deadline was reached before the action completed. +type ErrDeadline interface { + DeadlineExceeded() +} + +// ErrDataLoss indicates that data was lost or there is data corruption. +type ErrDataLoss interface { + DataLoss() +} diff --git a/libnetwork/vendor/github.com/docker/docker/errdefs/doc.go b/libnetwork/vendor/github.com/docker/docker/errdefs/doc.go new file mode 100644 index 0000000000..c211f174fc --- /dev/null +++ b/libnetwork/vendor/github.com/docker/docker/errdefs/doc.go @@ -0,0 +1,8 @@ +// Package errdefs defines a set of error interfaces that packages should use for communicating classes of errors. +// Errors that cross the package boundary should implement one (and only one) of these interfaces. +// +// Packages should not reference these interfaces directly, only implement them. +// To check if a particular error implements one of these interfaces, there are helper +// functions provided (e.g. `Is`) which can be used rather than asserting the interfaces directly. +// If you must assert on these interfaces, be sure to check the causal chain (`err.Cause()`). +package errdefs // import "github.com/docker/docker/errdefs" diff --git a/libnetwork/vendor/github.com/docker/docker/errdefs/helpers.go b/libnetwork/vendor/github.com/docker/docker/errdefs/helpers.go new file mode 100644 index 0000000000..6169c2bc62 --- /dev/null +++ b/libnetwork/vendor/github.com/docker/docker/errdefs/helpers.go @@ -0,0 +1,240 @@ +package errdefs // import "github.com/docker/docker/errdefs" + +import "context" + +type errNotFound struct{ error } + +func (errNotFound) NotFound() {} + +func (e errNotFound) Cause() error { + return e.error +} + +// NotFound is a helper to create an error of the class with the same name from any error type +func NotFound(err error) error { + if err == nil { + return nil + } + return errNotFound{err} +} + +type errInvalidParameter struct{ error } + +func (errInvalidParameter) InvalidParameter() {} + +func (e errInvalidParameter) Cause() error { + return e.error +} + +// InvalidParameter is a helper to create an error of the class with the same name from any error type +func InvalidParameter(err error) error { + if err == nil { + return nil + } + return errInvalidParameter{err} +} + +type errConflict struct{ error } + +func (errConflict) Conflict() {} + +func (e errConflict) Cause() error { + return e.error +} + +// Conflict is a helper to create an error of the class with the same name from any error type +func Conflict(err error) error { + if err == nil { + return nil + } + return errConflict{err} +} + +type errUnauthorized struct{ error } + +func (errUnauthorized) Unauthorized() {} + +func (e errUnauthorized) Cause() error { + return e.error +} + +// Unauthorized is a helper to create an error of the class with the same name from any error type +func Unauthorized(err error) error { + if err == nil { + return nil + } + return errUnauthorized{err} +} + +type errUnavailable struct{ error } + +func (errUnavailable) Unavailable() {} + +func (e errUnavailable) Cause() error { + return e.error +} + +// Unavailable is a helper to create an error of the class with the same name from any error type +func Unavailable(err error) error { + return errUnavailable{err} +} + +type errForbidden struct{ error } + +func (errForbidden) Forbidden() {} + +func (e errForbidden) Cause() error { + return e.error +} + +// Forbidden is a helper to create an error of the class with the same name from any error type +func Forbidden(err error) error { + if err == nil { + return nil + } + return errForbidden{err} +} + +type errSystem struct{ error } + +func (errSystem) System() {} + +func (e errSystem) Cause() error { + return e.error +} + +// System is a helper to create an error of the class with the same name from any error type +func System(err error) error { + if err == nil { + return nil + } + return errSystem{err} +} + +type errNotModified struct{ error } + +func (errNotModified) NotModified() {} + +func (e errNotModified) Cause() error { + return e.error +} + +// NotModified is a helper to create an error of the class with the same name from any error type +func NotModified(err error) error { + if err == nil { + return nil + } + return errNotModified{err} +} + +type errAlreadyExists struct{ error } + +func (errAlreadyExists) AlreadyExists() {} + +func (e errAlreadyExists) Cause() error { + return e.error +} + +// AlreadyExists is a helper to create an error of the class with the same name from any error type +func AlreadyExists(err error) error { + if err == nil { + return nil + } + return errAlreadyExists{err} +} + +type errNotImplemented struct{ error } + +func (errNotImplemented) NotImplemented() {} + +func (e errNotImplemented) Cause() error { + return e.error +} + +// NotImplemented is a helper to create an error of the class with the same name from any error type +func NotImplemented(err error) error { + if err == nil { + return nil + } + return errNotImplemented{err} +} + +type errUnknown struct{ error } + +func (errUnknown) Unknown() {} + +func (e errUnknown) Cause() error { + return e.error +} + +// Unknown is a helper to create an error of the class with the same name from any error type +func Unknown(err error) error { + if err == nil { + return nil + } + return errUnknown{err} +} + +type errCancelled struct{ error } + +func (errCancelled) Cancelled() {} + +func (e errCancelled) Cause() error { + return e.error +} + +// Cancelled is a helper to create an error of the class with the same name from any error type +func Cancelled(err error) error { + if err == nil { + return nil + } + return errCancelled{err} +} + +type errDeadline struct{ error } + +func (errDeadline) DeadlineExceeded() {} + +func (e errDeadline) Cause() error { + return e.error +} + +// Deadline is a helper to create an error of the class with the same name from any error type +func Deadline(err error) error { + if err == nil { + return nil + } + return errDeadline{err} +} + +type errDataLoss struct{ error } + +func (errDataLoss) DataLoss() {} + +func (e errDataLoss) Cause() error { + return e.error +} + +// DataLoss is a helper to create an error of the class with the same name from any error type +func DataLoss(err error) error { + if err == nil { + return nil + } + return errDataLoss{err} +} + +// FromContext returns the error class from the passed in context +func FromContext(ctx context.Context) error { + e := ctx.Err() + if e == nil { + return nil + } + + if e == context.Canceled { + return Cancelled(e) + } + if e == context.DeadlineExceeded { + return Deadline(e) + } + return Unknown(e) +} diff --git a/libnetwork/vendor/github.com/docker/docker/errdefs/is.go b/libnetwork/vendor/github.com/docker/docker/errdefs/is.go new file mode 100644 index 0000000000..e0513331bb --- /dev/null +++ b/libnetwork/vendor/github.com/docker/docker/errdefs/is.go @@ -0,0 +1,114 @@ +package errdefs // import "github.com/docker/docker/errdefs" + +type causer interface { + Cause() error +} + +func getImplementer(err error) error { + switch e := err.(type) { + case + ErrNotFound, + ErrInvalidParameter, + ErrConflict, + ErrUnauthorized, + ErrUnavailable, + ErrForbidden, + ErrSystem, + ErrNotModified, + ErrAlreadyExists, + ErrNotImplemented, + ErrCancelled, + ErrDeadline, + ErrDataLoss, + ErrUnknown: + return err + case causer: + return getImplementer(e.Cause()) + default: + return err + } +} + +// IsNotFound returns if the passed in error is an ErrNotFound +func IsNotFound(err error) bool { + _, ok := getImplementer(err).(ErrNotFound) + return ok +} + +// IsInvalidParameter returns if the passed in error is an ErrInvalidParameter +func IsInvalidParameter(err error) bool { + _, ok := getImplementer(err).(ErrInvalidParameter) + return ok +} + +// IsConflict returns if the passed in error is an ErrConflict +func IsConflict(err error) bool { + _, ok := getImplementer(err).(ErrConflict) + return ok +} + +// IsUnauthorized returns if the passed in error is an ErrUnauthorized +func IsUnauthorized(err error) bool { + _, ok := getImplementer(err).(ErrUnauthorized) + return ok +} + +// IsUnavailable returns if the passed in error is an ErrUnavailable +func IsUnavailable(err error) bool { + _, ok := getImplementer(err).(ErrUnavailable) + return ok +} + +// IsForbidden returns if the passed in error is an ErrForbidden +func IsForbidden(err error) bool { + _, ok := getImplementer(err).(ErrForbidden) + return ok +} + +// IsSystem returns if the passed in error is an ErrSystem +func IsSystem(err error) bool { + _, ok := getImplementer(err).(ErrSystem) + return ok +} + +// IsNotModified returns if the passed in error is a NotModified error +func IsNotModified(err error) bool { + _, ok := getImplementer(err).(ErrNotModified) + return ok +} + +// IsAlreadyExists returns if the passed in error is a AlreadyExists error +func IsAlreadyExists(err error) bool { + _, ok := getImplementer(err).(ErrAlreadyExists) + return ok +} + +// IsNotImplemented returns if the passed in error is an ErrNotImplemented +func IsNotImplemented(err error) bool { + _, ok := getImplementer(err).(ErrNotImplemented) + return ok +} + +// IsUnknown returns if the passed in error is an ErrUnknown +func IsUnknown(err error) bool { + _, ok := getImplementer(err).(ErrUnknown) + return ok +} + +// IsCancelled returns if the passed in error is an ErrCancelled +func IsCancelled(err error) bool { + _, ok := getImplementer(err).(ErrCancelled) + return ok +} + +// IsDeadline returns if the passed in error is an ErrDeadline +func IsDeadline(err error) bool { + _, ok := getImplementer(err).(ErrDeadline) + return ok +} + +// IsDataLoss returns if the passed in error is an ErrDataLoss +func IsDataLoss(err error) bool { + _, ok := getImplementer(err).(ErrDataLoss) + return ok +} diff --git a/libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs.go b/libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs.go new file mode 100644 index 0000000000..7b894cde73 --- /dev/null +++ b/libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs.go @@ -0,0 +1,144 @@ +// Copyright 2012 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE.BSD file. + +// This code is a modified version of path/filepath/symlink.go from the Go standard library. + +package symlink // import "github.com/docker/docker/pkg/symlink" + +import ( + "bytes" + "errors" + "os" + "path/filepath" + "strings" + + "github.com/docker/docker/pkg/system" +) + +// FollowSymlinkInScope is a wrapper around evalSymlinksInScope that returns an +// absolute path. This function handles paths in a platform-agnostic manner. +func FollowSymlinkInScope(path, root string) (string, error) { + path, err := filepath.Abs(filepath.FromSlash(path)) + if err != nil { + return "", err + } + root, err = filepath.Abs(filepath.FromSlash(root)) + if err != nil { + return "", err + } + return evalSymlinksInScope(path, root) +} + +// evalSymlinksInScope will evaluate symlinks in `path` within a scope `root` and return +// a result guaranteed to be contained within the scope `root`, at the time of the call. +// Symlinks in `root` are not evaluated and left as-is. +// Errors encountered while attempting to evaluate symlinks in path will be returned. +// Non-existing paths are valid and do not constitute an error. +// `path` has to contain `root` as a prefix, or else an error will be returned. +// Trying to break out from `root` does not constitute an error. +// +// Example: +// If /foo/bar -> /outside, +// FollowSymlinkInScope("/foo/bar", "/foo") == "/foo/outside" instead of "/outside" +// +// IMPORTANT: it is the caller's responsibility to call evalSymlinksInScope *after* relevant symlinks +// are created and not to create subsequently, additional symlinks that could potentially make a +// previously-safe path, unsafe. Example: if /foo/bar does not exist, evalSymlinksInScope("/foo/bar", "/foo") +// would return "/foo/bar". If one makes /foo/bar a symlink to /baz subsequently, then "/foo/bar" should +// no longer be considered safely contained in "/foo". +func evalSymlinksInScope(path, root string) (string, error) { + root = filepath.Clean(root) + if path == root { + return path, nil + } + if !strings.HasPrefix(path, root) { + return "", errors.New("evalSymlinksInScope: " + path + " is not in " + root) + } + const maxIter = 255 + originalPath := path + // given root of "/a" and path of "/a/b/../../c" we want path to be "/b/../../c" + path = path[len(root):] + if root == string(filepath.Separator) { + path = string(filepath.Separator) + path + } + if !strings.HasPrefix(path, string(filepath.Separator)) { + return "", errors.New("evalSymlinksInScope: " + path + " is not in " + root) + } + path = filepath.Clean(path) + // consume path by taking each frontmost path element, + // expanding it if it's a symlink, and appending it to b + var b bytes.Buffer + // b here will always be considered to be the "current absolute path inside + // root" when we append paths to it, we also append a slash and use + // filepath.Clean after the loop to trim the trailing slash + for n := 0; path != ""; n++ { + if n > maxIter { + return "", errors.New("evalSymlinksInScope: too many links in " + originalPath) + } + + // find next path component, p + i := strings.IndexRune(path, filepath.Separator) + var p string + if i == -1 { + p, path = path, "" + } else { + p, path = path[:i], path[i+1:] + } + + if p == "" { + continue + } + + // this takes a b.String() like "b/../" and a p like "c" and turns it + // into "/b/../c" which then gets filepath.Cleaned into "/c" and then + // root gets prepended and we Clean again (to remove any trailing slash + // if the first Clean gave us just "/") + cleanP := filepath.Clean(string(filepath.Separator) + b.String() + p) + if isDriveOrRoot(cleanP) { + // never Lstat "/" itself, or drive letters on Windows + b.Reset() + continue + } + fullP := filepath.Clean(root + cleanP) + + fi, err := os.Lstat(fullP) + if os.IsNotExist(err) { + // if p does not exist, accept it + b.WriteString(p) + b.WriteRune(filepath.Separator) + continue + } + if err != nil { + return "", err + } + if fi.Mode()&os.ModeSymlink == 0 { + b.WriteString(p) + b.WriteRune(filepath.Separator) + continue + } + + // it's a symlink, put it at the front of path + dest, err := os.Readlink(fullP) + if err != nil { + return "", err + } + if system.IsAbs(dest) { + b.Reset() + } + path = dest + string(filepath.Separator) + path + } + + // see note above on "fullP := ..." for why this is double-cleaned and + // what's happening here + return filepath.Clean(root + filepath.Clean(string(filepath.Separator)+b.String())), nil +} + +// EvalSymlinks returns the path name after the evaluation of any symbolic +// links. +// If path is relative the result will be relative to the current directory, +// unless one of the components is an absolute symbolic link. +// This version has been updated to support long paths prepended with `\\?\`. +func EvalSymlinks(path string) (string, error) { + return evalSymlinks(path) +} diff --git a/libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs_unix.go b/libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs_unix.go new file mode 100644 index 0000000000..c6dafcb0b9 --- /dev/null +++ b/libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs_unix.go @@ -0,0 +1,15 @@ +// +build !windows + +package symlink // import "github.com/docker/docker/pkg/symlink" + +import ( + "path/filepath" +) + +func evalSymlinks(path string) (string, error) { + return filepath.EvalSymlinks(path) +} + +func isDriveOrRoot(p string) bool { + return p == string(filepath.Separator) +} diff --git a/libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs_windows.go b/libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs_windows.go new file mode 100644 index 0000000000..754761717b --- /dev/null +++ b/libnetwork/vendor/github.com/docker/docker/pkg/symlink/fs_windows.go @@ -0,0 +1,169 @@ +package symlink // import "github.com/docker/docker/pkg/symlink" + +import ( + "bytes" + "errors" + "os" + "path/filepath" + "strings" + + "github.com/docker/docker/pkg/longpath" + "golang.org/x/sys/windows" +) + +func toShort(path string) (string, error) { + p, err := windows.UTF16FromString(path) + if err != nil { + return "", err + } + b := p // GetShortPathName says we can reuse buffer + n, err := windows.GetShortPathName(&p[0], &b[0], uint32(len(b))) + if err != nil { + return "", err + } + if n > uint32(len(b)) { + b = make([]uint16, n) + if _, err = windows.GetShortPathName(&p[0], &b[0], uint32(len(b))); err != nil { + return "", err + } + } + return windows.UTF16ToString(b), nil +} + +func toLong(path string) (string, error) { + p, err := windows.UTF16FromString(path) + if err != nil { + return "", err + } + b := p // GetLongPathName says we can reuse buffer + n, err := windows.GetLongPathName(&p[0], &b[0], uint32(len(b))) + if err != nil { + return "", err + } + if n > uint32(len(b)) { + b = make([]uint16, n) + n, err = windows.GetLongPathName(&p[0], &b[0], uint32(len(b))) + if err != nil { + return "", err + } + } + b = b[:n] + return windows.UTF16ToString(b), nil +} + +func evalSymlinks(path string) (string, error) { + path, err := walkSymlinks(path) + if err != nil { + return "", err + } + + p, err := toShort(path) + if err != nil { + return "", err + } + p, err = toLong(p) + if err != nil { + return "", err + } + // windows.GetLongPathName does not change the case of the drive letter, + // but the result of EvalSymlinks must be unique, so we have + // EvalSymlinks(`c:\a`) == EvalSymlinks(`C:\a`). + // Make drive letter upper case. + if len(p) >= 2 && p[1] == ':' && 'a' <= p[0] && p[0] <= 'z' { + p = string(p[0]+'A'-'a') + p[1:] + } else if len(p) >= 6 && p[5] == ':' && 'a' <= p[4] && p[4] <= 'z' { + p = p[:3] + string(p[4]+'A'-'a') + p[5:] + } + return filepath.Clean(p), nil +} + +const utf8RuneSelf = 0x80 + +func walkSymlinks(path string) (string, error) { + const maxIter = 255 + originalPath := path + // consume path by taking each frontmost path element, + // expanding it if it's a symlink, and appending it to b + var b bytes.Buffer + for n := 0; path != ""; n++ { + if n > maxIter { + return "", errors.New("EvalSymlinks: too many links in " + originalPath) + } + + // A path beginning with `\\?\` represents the root, so automatically + // skip that part and begin processing the next segment. + if strings.HasPrefix(path, longpath.Prefix) { + b.WriteString(longpath.Prefix) + path = path[4:] + continue + } + + // find next path component, p + var i = -1 + for j, c := range path { + if c < utf8RuneSelf && os.IsPathSeparator(uint8(c)) { + i = j + break + } + } + var p string + if i == -1 { + p, path = path, "" + } else { + p, path = path[:i], path[i+1:] + } + + if p == "" { + if b.Len() == 0 { + // must be absolute path + b.WriteRune(filepath.Separator) + } + continue + } + + // If this is the first segment after the long path prefix, accept the + // current segment as a volume root or UNC share and move on to the next. + if b.String() == longpath.Prefix { + b.WriteString(p) + b.WriteRune(filepath.Separator) + continue + } + + fi, err := os.Lstat(b.String() + p) + if err != nil { + return "", err + } + if fi.Mode()&os.ModeSymlink == 0 { + b.WriteString(p) + if path != "" || (b.Len() == 2 && len(p) == 2 && p[1] == ':') { + b.WriteRune(filepath.Separator) + } + continue + } + + // it's a symlink, put it at the front of path + dest, err := os.Readlink(b.String() + p) + if err != nil { + return "", err + } + if filepath.IsAbs(dest) || os.IsPathSeparator(dest[0]) { + b.Reset() + } + path = dest + string(filepath.Separator) + path + } + return filepath.Clean(b.String()), nil +} + +func isDriveOrRoot(p string) bool { + if p == string(filepath.Separator) { + return true + } + + length := len(p) + if length >= 2 { + if p[length-1] == ':' && (('a' <= p[length-2] && p[length-2] <= 'z') || ('A' <= p[length-2] && p[length-2] <= 'Z')) { + return true + } + } + return false +}