system

Documentation

Index

• Variables
• func CheckSystemDriveAndRemoveDriveLetter(path string, driver PathVerifier) (string, error)
• func Chtimes(name string, atime time.Time, mtime time.Time) error
• func CreateSequential(name string) (*os.File, error)
• func DefaultPathEnv(os string) string
• func GetLongPathName(path string) (string, error)
• func IsAbs(path string) bool
• func IsOSSupported(os string) bool
• func IsProcessAlive(pid int) bool
• func IsProcessZombie(pid int) (bool, error)
• func KillProcess(pid int)
• func LUtimesNano(path string, ts []syscall.Timespec) error
• func Lgetxattr(path string, attr string) ([]byte, error)
• func Lsetxattr(path string, attr string, data []byte, flags int) error
• func Mkdev(major int64, minor int64) uint32
• func MkdirAll(path string, perm os.FileMode) error
• func MkdirAllWithACL(path string, perm os.FileMode, sddl string) error
• func Mknod(path string, mode uint32, dev int) error
• func OpenFileSequential(name string, flag int, perm os.FileMode) (*os.File, error)
• func OpenSequential(name string) (*os.File, error)
• func TempFileSequential(dir, prefix string) (f *os.File, err error)
• type MemInfo
  • func ReadMemInfo() (*MemInfo, error)
• type PathVerifier
• type StatT
  • func FromStatT(s *syscall.Stat_t) (*StatT, error)
  • func Lstat(path string) (*StatT, error)
  • func Stat(path string) (*StatT, error)
  • func (s StatT) GID() uint32
  • func (s StatT) IsDir() bool
  • func (s StatT) Mode() uint32
  • func (s StatT) Mtim() syscall.Timespec
  • func (s StatT) Rdev() uint64
  • func (s StatT) Size() int64
  • func (s StatT) UID() uint32

Variables

var (
	// ErrNotSupportedPlatform means the platform is not supported.
	ErrNotSupportedPlatform = errors.New("platform and architecture is not supported")

	// ErrNotSupportedOperatingSystem means the operating system is not supported.
	ErrNotSupportedOperatingSystem = errors.New("operating system is not supported")
)

Functions

func CheckSystemDriveAndRemoveDriveLetter

func CheckSystemDriveAndRemoveDriveLetter(path string, driver PathVerifier) (string, error)

CheckSystemDriveAndRemoveDriveLetter verifies that a path, if it includes a drive letter, is the system drive. On Linux: this is a no-op. On Windows: this does the following> CheckSystemDriveAndRemoveDriveLetter verifies and manipulates a Windows path. This is used, for example, when validating a user provided path in docker cp. If a drive letter is supplied, it must be the system drive. The drive letter is always removed. Also, it translates it to OS semantics (IOW / to \). We need the path in this syntax so that it can ultimately be concatenated with a Windows long-path which doesn't support drive-letters. Examples: C: --> Fail C:\ --> \ a --> a /a --> \a d:\ --> Fail

func Chtimes

func Chtimes(name string, atime time.Time, mtime time.Time) error

Chtimes changes the access time and modified time of a file at the given path

func CreateSequential

func CreateSequential(name string) (*os.File, error)

CreateSequential is deprecated.

Deprecated: use os.Create or github.com/moby/sys/sequential.Create()

func DefaultPathEnv

func DefaultPathEnv(os string) string

DefaultPathEnv is unix style list of directories to search for executables. Each directory is separated from the next by a colon ':' character . For Windows containers, an empty string is returned as the default path will be set by the container, and Docker has no context of what the default path should be.

func GetLongPathName

func GetLongPathName(path string) (string, error)

GetLongPathName converts Windows short pathnames to full pathnames. For example C:\Users\ADMIN~1 --> C:\Users\Administrator. It is a no-op on non-Windows platforms

func IsAbs

func IsAbs(path string) bool

IsAbs is a platform-agnostic wrapper for filepath.IsAbs.

On Windows, golang filepath.IsAbs does not consider a path \windows\system32 as absolute as it doesn't start with a drive-letter/colon combination. However, in docker we need to verify things such as WORKDIR /windows/system32 in a Dockerfile (which gets translated to \windows\system32 when being processed by the daemon). This SHOULD be treated as absolute from a docker processing perspective.

func IsOSSupported

func IsOSSupported(os string) bool

IsOSSupported determines if an operating system is supported by the host.

func IsProcessAlive

func IsProcessAlive(pid int) bool

IsProcessAlive returns true if process with a given pid is running.

func IsProcessZombie

func IsProcessZombie(pid int) (bool, error)

IsProcessZombie return true if process has a state with "Z" http://man7.org/linux/man-pages/man5/proc.5.html

func KillProcess

func KillProcess(pid int)

KillProcess force-stops a process.

func LUtimesNano

func LUtimesNano(path string, ts []syscall.Timespec) error

LUtimesNano is used to change access and modification time of the specified path. It's used for symbol link file because unix.UtimesNano doesn't support a NOFOLLOW flag atm.

func Lgetxattr

func Lgetxattr(path string, attr string) ([]byte, error)

Lgetxattr retrieves the value of the extended attribute identified by attr and associated with the given path in the file system. It will returns a nil slice and nil error if the xattr is not set.

func Lsetxattr

func Lsetxattr(path string, attr string, data []byte, flags int) error

Lsetxattr sets the value of the extended attribute identified by attr and associated with the given path in the file system.

func Mkdev

func Mkdev(major int64, minor int64) uint32

Mkdev is used to build the value of linux devices (in /dev/) which specifies major and minor number of the newly created device special file. Linux device nodes are a bit weird due to backwards compat with 16 bit device nodes. They are, from low to high: the lower 8 bits of the minor, then 12 bits of the major, then the top 12 bits of the minor.

func MkdirAll

func MkdirAll(path string, perm os.FileMode) error

MkdirAll creates a directory named path along with any necessary parents, with permission specified by attribute perm for all dir created.

func MkdirAllWithACL

func MkdirAllWithACL(path string, perm os.FileMode, sddl string) error

MkdirAllWithACL is a wrapper for os.MkdirAll on unix systems.

func Mknod

func Mknod(path string, mode uint32, dev int) error

Mknod creates a filesystem node (file, device special file or named pipe) named path with attributes specified by mode and dev.

func OpenFileSequential

func OpenFileSequential(name string, flag int, perm os.FileMode) (*os.File, error)

OpenFileSequential is deprecated.

Deprecated: use github.com/moby/sys/sequential.OpenFile()

func OpenSequential

func OpenSequential(name string) (*os.File, error)

OpenSequential is deprecated.

Deprecated: use os.Open or github.com/moby/sys/sequential.Open

func TempFileSequential

func TempFileSequential(dir, prefix string) (f *os.File, err error)

TempFileSequential is deprecated.

Deprecated: use os.CreateTemp or github.com/moby/sys/sequential.CreateTemp

Types

type MemInfo

type MemInfo struct {
	// Total usable RAM (i.e. physical RAM minus a few reserved bits and the
	// kernel binary code).
	MemTotal int64

	// Amount of free memory.
	MemFree int64

	// Total amount of swap space available.
	SwapTotal int64

	// Amount of swap space that is currently unused.
	SwapFree int64
}

MemInfo contains memory statistics of the host system.

func ReadMemInfo

func ReadMemInfo() (*MemInfo, error)

ReadMemInfo retrieves memory statistics of the host system and returns a MemInfo type.

type PathVerifier

type PathVerifier interface {
	IsAbs(string) bool
}

PathVerifier defines the subset of a PathDriver that CheckSystemDriveAndRemoveDriveLetter actually uses in order to avoid system depending on containerd/continuity.

type StatT

type StatT struct {
	// contains filtered or unexported fields
}

StatT type contains status of a file. It contains metadata like permission, owner, group, size, etc about a file.

func FromStatT

func FromStatT(s *syscall.Stat_t) (*StatT, error)

FromStatT converts a syscall.Stat_t type to a system.Stat_t type This is exposed on Linux as pkg/archive/changes uses it.

func Lstat

func Lstat(path string) (*StatT, error)

Lstat takes a path to a file and returns a system.StatT type pertaining to that file.

Throws an error if the file does not exist

func Stat

func Stat(path string) (*StatT, error)

Stat takes a path to a file and returns a system.StatT type pertaining to that file.

Throws an error if the file does not exist

func (StatT) GID

func (s StatT) GID() uint32

GID returns file's group id of owner.

func (StatT) IsDir

func (s StatT) IsDir() bool

IsDir reports whether s describes a directory.

func (StatT) Mode

func (s StatT) Mode() uint32

Mode returns file's permission mode.

func (StatT) Mtim

func (s StatT) Mtim() syscall.Timespec

Mtim returns file's last modification time.

func (StatT) Rdev

func (s StatT) Rdev() uint64

Rdev returns file's device ID (if it's special file).

func (StatT) Size

func (s StatT) Size() int64

Size returns file's size.

func (StatT) UID

func (s StatT) UID() uint32

UID returns file's user id of owner.