github.com/vieux/docker@v0.6.3-0.20161004191708-e097c2a938c7/container/archive.go (about)

     1  package container
     2  
     3  import (
     4  	"os"
     5  	"path/filepath"
     6  
     7  	"github.com/docker/docker/api/types"
     8  	"github.com/docker/docker/pkg/archive"
     9  	"github.com/docker/docker/pkg/system"
    10  )
    11  
    12  // ResolvePath resolves the given path in the container to a resource on the
    13  // host. Returns a resolved path (absolute path to the resource on the host),
    14  // the absolute path to the resource relative to the container's rootfs, and
    15  // an error if the path points to outside the container's rootfs.
    16  func (container *Container) ResolvePath(path string) (resolvedPath, absPath string, err error) {
    17  	// Check if a drive letter supplied, it must be the system drive. No-op except on Windows
    18  	path, err = system.CheckSystemDriveAndRemoveDriveLetter(path)
    19  	if err != nil {
    20  		return "", "", err
    21  	}
    22  
    23  	// Consider the given path as an absolute path in the container.
    24  	absPath = archive.PreserveTrailingDotOrSeparator(filepath.Join(string(filepath.Separator), path), path)
    25  
    26  	// Split the absPath into its Directory and Base components. We will
    27  	// resolve the dir in the scope of the container then append the base.
    28  	dirPath, basePath := filepath.Split(absPath)
    29  
    30  	resolvedDirPath, err := container.GetResourcePath(dirPath)
    31  	if err != nil {
    32  		return "", "", err
    33  	}
    34  
    35  	// resolvedDirPath will have been cleaned (no trailing path separators) so
    36  	// we can manually join it with the base path element.
    37  	resolvedPath = resolvedDirPath + string(filepath.Separator) + basePath
    38  
    39  	return resolvedPath, absPath, nil
    40  }
    41  
    42  // StatPath is the unexported version of StatPath. Locks and mounts should
    43  // be acquired before calling this method and the given path should be fully
    44  // resolved to a path on the host corresponding to the given absolute path
    45  // inside the container.
    46  func (container *Container) StatPath(resolvedPath, absPath string) (stat *types.ContainerPathStat, err error) {
    47  	lstat, err := os.Lstat(resolvedPath)
    48  	if err != nil {
    49  		return nil, err
    50  	}
    51  
    52  	var linkTarget string
    53  	if lstat.Mode()&os.ModeSymlink != 0 {
    54  		// Fully evaluate the symlink in the scope of the container rootfs.
    55  		hostPath, err := container.GetResourcePath(absPath)
    56  		if err != nil {
    57  			return nil, err
    58  		}
    59  
    60  		linkTarget, err = filepath.Rel(container.BaseFS, hostPath)
    61  		if err != nil {
    62  			return nil, err
    63  		}
    64  
    65  		// Make it an absolute path.
    66  		linkTarget = filepath.Join(string(filepath.Separator), linkTarget)
    67  	}
    68  
    69  	return &types.ContainerPathStat{
    70  		Name:       filepath.Base(absPath),
    71  		Size:       lstat.Size(),
    72  		Mode:       lstat.Mode(),
    73  		Mtime:      lstat.ModTime(),
    74  		LinkTarget: linkTarget,
    75  	}, nil
    76  }