moby/container/archive.go
Cory Snider be4f4644a8 pkg/containerfs: drop Driver abstraction
The Driver abstraction was needed for Linux Containers on Windows,
support for which has since been removed.

There is no direct equivalent to Lchmod() in the standard library so
continue to use the containerd/continuity version.

Signed-off-by: Cory Snider <csnider@mirantis.com>
2022-09-23 16:25:22 -04:00

84 lines
2.8 KiB
Go

package container // import "github.com/docker/docker/container"
import (
"os"
"path/filepath"
"github.com/docker/docker/api/types"
"github.com/docker/docker/pkg/archive"
"github.com/docker/docker/pkg/system"
"github.com/pkg/errors"
)
// ResolvePath resolves the given path in the container to a resource on the
// host. Returns a resolved path (absolute path to the resource on the host),
// the absolute path to the resource relative to the container's rootfs, and
// an error if the path points to outside the container's rootfs.
func (container *Container) ResolvePath(path string) (resolvedPath, absPath string, err error) {
if container.BaseFS == nil {
return "", "", errors.New("ResolvePath: BaseFS of container " + container.ID + " is unexpectedly nil")
}
// Check if a drive letter supplied, it must be the system drive. No-op except on Windows
path, err = system.CheckSystemDriveAndRemoveDriveLetter(path)
if err != nil {
return "", "", err
}
// Consider the given path as an absolute path in the container.
absPath = archive.PreserveTrailingDotOrSeparator(filepath.Join(string(filepath.Separator), path), path)
// Split the absPath into its Directory and Base components. We will
// resolve the dir in the scope of the container then append the base.
dirPath, basePath := filepath.Split(absPath)
resolvedDirPath, err := container.GetResourcePath(dirPath)
if err != nil {
return "", "", err
}
// resolvedDirPath will have been cleaned (no trailing path separators) so
// we can manually join it with the base path element.
resolvedPath = resolvedDirPath + string(filepath.Separator) + basePath
return resolvedPath, absPath, nil
}
// StatPath is the unexported version of StatPath. Locks and mounts should
// be acquired before calling this method and the given path should be fully
// resolved to a path on the host corresponding to the given absolute path
// inside the container.
func (container *Container) StatPath(resolvedPath, absPath string) (stat *types.ContainerPathStat, err error) {
if container.BaseFS == nil {
return nil, errors.New("StatPath: BaseFS of container " + container.ID + " is unexpectedly nil")
}
driver := container.BaseFS
lstat, err := os.Lstat(resolvedPath)
if err != nil {
return nil, err
}
var linkTarget string
if lstat.Mode()&os.ModeSymlink != 0 {
// Fully evaluate the symlink in the scope of the container rootfs.
hostPath, err := container.GetResourcePath(absPath)
if err != nil {
return nil, err
}
linkTarget, err = filepath.Rel(driver.Path(), hostPath)
if err != nil {
return nil, err
}
// Make it an absolute path.
linkTarget = filepath.Join(string(filepath.Separator), linkTarget)
}
return &types.ContainerPathStat{
Name: filepath.Base(absPath),
Size: lstat.Size(),
Mode: lstat.Mode(),
Mtime: lstat.ModTime(),
LinkTarget: linkTarget,
}, nil
}