Files
snapd/dirs/dirs.go
alfonsosanchezbeato b052830f37 many: build drivers tree on install (#13923)
Build drivers tree on installation so kernel modules can be found on first boot after installation (otherwise the modules would be available too late, after initial installation of the kernel has happened while seeding).

Also, make sure that the tree is not re-created when seeding, and add a spread test for kernel-modules components.

* dirs: add function to get root of drivers trees

* kernel: do not recreate drivers tree if it already exists

On installation, a drivers tree has already been copied to the data
partition. Do not re-create if found when seeding happens (note though
that on preseeding we will not find the tree and we will still create
it).

* gadget/install: create device tree on installations

Create a device tree on installation so we have it on first boot.

* o/snapstate: fix task message

* tests/nested/manual: add kernel-modules-components test

This test installs a kernel-modules component and verifies that the
shipped kernel module is installed and can be loaded.

* tests/lib: do not error out if cloud-init finished with

'recoverable error' status.

* kernel: have destination as argument when building drivers tree

We need to tackle the generic installation case as opposed to creating
the drivers tree when seeding the system. In that case the destination
tree can vary depending on installation type.

* overlord: pass kernel information to install package

so the drivers tree can be created.

* cmd/snap-bootstrap: build drivers tree on installation from initramfs

* tests: adapt to additional parameters in install.Run

* snap/naming: add ancillary method to split a full component name

into snap and component names.

* gadget/install: fix nosecboot tests
2024-05-29 15:58:22 +01:00

641 lines
21 KiB
Go

// -*- Mode: Go; indent-tabs-mode: t -*-
/*
* Copyright (C) 2014-2015 Canonical Ltd
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 3 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
package dirs
import (
"fmt"
"os"
"path/filepath"
"strconv"
"strings"
"sync"
"github.com/snapcore/snapd/release"
"github.com/snapcore/snapd/strutil"
)
// the various file paths
var (
GlobalRootDir string = "/"
RunDir string
SnapMountDir string
DistroLibExecDir string
hiddenSnapDataHomeGlob []string
SnapBlobDir string
SnapDataDir string
snapDataHomeGlob []string
SnapDownloadCacheDir string
SnapAppArmorDir string
SnapSeccompBase string
SnapSeccompDir string
SnapMountPolicyDir string
SnapCgroupPolicyDir string
SnapUdevRulesDir string
SnapKModModulesDir string
SnapKModModprobeDir string
LocaleDir string
SnapdSocket string
SnapSocket string
SnapRunDir string
SnapRunNsDir string
SnapRunLockDir string
SnapBootstrapRunDir string
SnapVoidDir string
SnapdMaintenanceFile string
SnapdStoreSSLCertsDir string
SnapSeedDir string
SnapDeviceDir string
SnapAssertsDBDir string
SnapCookieDir string
SnapTrustedAccountKey string
SnapAssertsSpoolDir string
SnapSeqDir string
SnapStateFile string
SnapStateLockFile string
SnapSystemKeyFile string
SnapRepairConfigFile string
SnapRepairDir string
SnapRepairStateFile string
SnapRepairRunDir string
SnapRepairAssertsDir string
SnapRunRepairDir string
SnapRollbackDir string
SnapCacheDir string
SnapNamesFile string
SnapSectionsFile string
SnapCommandsDB string
SnapAuxStoreInfoDir string
SnapBinariesDir string
SnapServicesDir string
SnapRuntimeServicesDir string
SnapUserServicesDir string
SnapSystemdConfDir string
SnapDesktopFilesDir string
SnapDesktopIconsDir string
SnapPolkitPolicyDir string
SnapSystemdDir string
SnapSystemdRunDir string
SnapDBusSessionPolicyDir string
SnapDBusSystemPolicyDir string
SnapDBusSessionServicesDir string
SnapDBusSystemServicesDir string
SnapModeenvFile string
SnapBootAssetsDir string
SnapFDEDir string
SnapSaveDir string
SnapDeviceSaveDir string
SnapDataSaveDir string
CloudMetaDataFile string
CloudInstanceDataFile string
ClassicDir string
XdgRuntimeDirBase string
XdgRuntimeDirGlob string
CompletionHelperInCore string
BashCompletionScript string
LegacyCompletersDir string
CompletersDir string
SystemFontsDir string
SystemLocalFontsDir string
SystemFontconfigCacheDirs []string
SnapshotsDir string
SysfsDir string
FeaturesDir string
)
// User defined home directory variables
// Not exported, use SnapHomeDirs() and SetSnapHomeDirs() instead
var (
snapHomeDirsMu sync.Mutex
snapHomeDirs []string
)
const (
defaultSnapMountDir = "/snap"
// These are directories which are static inside the core snap and
// can never be prefixed as they will be always absolute once we
// are in the snap confinement environment.
CoreLibExecDir = "/usr/lib/snapd"
CoreSnapMountDir = "/snap"
// UserHomeSnapDir is the directory with snap data inside user's home
UserHomeSnapDir = "snap"
// HiddenSnapDataHomeDir is an experimental hidden directory for snap data
HiddenSnapDataHomeDir = ".snap/data"
// ExposedSnapHomeDir is the directory where snaps should place user-facing
// data after ~/snap has been migrated to ~/.snap
ExposedSnapHomeDir = "Snap"
// LocalInstallBlobTempPrefix is used by local install code:
// * in daemon to spool the snap file to <SnapBlobDir>/<LocalInstallBlobTempPrefix>*
// * in snapstate to auto-cleans them up using the same prefix
LocalInstallBlobTempPrefix = ".local-install-"
)
var (
// not exported because it does not honor the global rootdir
snappyDir = filepath.Join("var", "lib", "snapd")
callbacks = []func(string){}
)
type SnapDirOptions struct {
// HiddenSnapDataDir determines if the snaps' data is in ~/.snap/data instead
// of ~/snap
HiddenSnapDataDir bool
// MigratedToExposedHome determines if the snap's directory in ~/Snap has been
// initialized with the contents of the snap's previous home (i.e., the
// revisioned data directory).
MigratedToExposedHome bool
}
func init() {
// init the global directories at startup
root := os.Getenv("SNAPPY_GLOBAL_ROOT")
SetRootDir(root)
}
// SnapHomeDirs returns a slice of the currently configured home directories.
func SnapHomeDirs() []string {
snapHomeDirsMu.Lock()
defer snapHomeDirsMu.Unlock()
dirs := make([]string, len(snapHomeDirs))
copy(dirs, snapHomeDirs)
// Should never be true since SetSnapHomeDirs is run on init and on SetRootDir calls.
// Useful for unit tests.
if len(dirs) == 0 {
return []string{filepath.Join(GlobalRootDir, "/home")}
}
return dirs
}
// SetSnapHomeDirs sets SnapHomeDirs to the user defined values and appends /home if needed.
// homedirs must be a comma separated list of paths to home directories.
// If homedirs is empty, SnapHomeDirs will be a slice of length 1 containing "/home".
// Also generates the data directory globbing expressions for each user.
// Expected to be run by configstate.Init, returns a slice of home directories.
func SetSnapHomeDirs(homedirs string) []string {
snapHomeDirsMu.Lock()
defer snapHomeDirsMu.Unlock()
//clear old values
snapHomeDirs = nil
snapDataHomeGlob = nil
hiddenSnapDataHomeGlob = nil
// Do not set the root directory as home unless explicitly specified with "."
if homedirs != "" {
snapHomeDirs = strings.Split(homedirs, ",")
for i := range snapHomeDirs {
// clean the path
snapHomeDirs[i] = filepath.Clean(snapHomeDirs[i])
globalRootDir := GlobalRootDir
// Avoid false positives with HasPrefix
if globalRootDir != "/" && !strings.HasSuffix(globalRootDir, "/") {
globalRootDir += "/"
}
if !strings.HasPrefix(snapHomeDirs[i], globalRootDir) {
snapHomeDirs[i] = filepath.Join(GlobalRootDir, snapHomeDirs[i])
}
// Generate data directory globbing expressions for each user.
snapDataHomeGlob = append(snapDataHomeGlob, filepath.Join(snapHomeDirs[i], "*", UserHomeSnapDir))
hiddenSnapDataHomeGlob = append(hiddenSnapDataHomeGlob, filepath.Join(snapHomeDirs[i], "*", HiddenSnapDataHomeDir))
}
}
// Make sure /home is part of the list.
hasHome := strutil.ListContains(snapHomeDirs, filepath.Join(GlobalRootDir, "/home"))
// if not add it and create the glob expressions.
if !hasHome {
snapHomeDirs = append(snapHomeDirs, filepath.Join(GlobalRootDir, "/home"))
snapDataHomeGlob = append(snapDataHomeGlob, filepath.Join(GlobalRootDir, "/home", "*", UserHomeSnapDir))
hiddenSnapDataHomeGlob = append(hiddenSnapDataHomeGlob, filepath.Join(GlobalRootDir, "/home", "*", HiddenSnapDataHomeDir))
}
return snapHomeDirs
}
// StripRootDir strips the custom global root directory from the specified argument.
func StripRootDir(dir string) string {
if !filepath.IsAbs(dir) {
panic(fmt.Sprintf("supplied path is not absolute %q", dir))
}
if !strings.HasPrefix(dir, GlobalRootDir) {
panic(fmt.Sprintf("supplied path is not related to global root %q", dir))
}
result, err := filepath.Rel(GlobalRootDir, dir)
if err != nil {
panic(err)
}
return "/" + result
}
// DataHomeGlobs returns a slice of globbing expressions for the snap directories in use.
func DataHomeGlobs(opts *SnapDirOptions) []string {
snapHomeDirsMu.Lock()
defer snapHomeDirsMu.Unlock()
if opts != nil && opts.HiddenSnapDataDir {
return hiddenSnapDataHomeGlob
}
return snapDataHomeGlob
}
// SupportsClassicConfinement returns true if the current directory layout supports classic confinement.
func SupportsClassicConfinement() bool {
// Core systems don't support classic confinement as a policy decision.
if !release.OnClassic {
return false
}
// Classic systems support classic confinement if using the primary mount
// location for snaps, that is /snap or if using the alternate mount
// location, /var/lib/snapd/snap along with the /snap ->
// /var/lib/snapd/snap symlink in place.
smd := filepath.Join(GlobalRootDir, defaultSnapMountDir)
if SnapMountDir == smd {
return true
}
fi, err := os.Lstat(smd)
if err == nil && fi.Mode()&os.ModeSymlink != 0 {
if target, err := filepath.EvalSymlinks(smd); err == nil {
if target == SnapMountDir {
return true
}
}
}
return false
}
var metaSnapPath = "/meta/snap.yaml"
// isInsideBaseSnap returns true if the process is inside a base snap environment.
//
// The things that count as a base snap are:
// - any base snap mounted at /
// - any os snap mounted at /
func isInsideBaseSnap() (bool, error) {
_, err := os.Stat(metaSnapPath)
if err != nil && os.IsNotExist(err) {
return false, nil
}
return err == nil, err
}
// SnapdStateDir returns the path to /var/lib/snapd dir under rootdir.
func SnapdStateDir(rootdir string) string {
return filepath.Join(rootdir, snappyDir)
}
// SnapBlobDirUnder returns the path to the snap blob dir under rootdir.
func SnapBlobDirUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "snaps")
}
// SnapSeedDirUnder returns the path to the snap seed dir under rootdir.
func SnapSeedDirUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "seed")
}
// SnapStateFileUnder returns the path to snapd state file under rootdir.
func SnapStateFileUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "state.json")
}
// SnapStateLockFileUnder returns the path to snapd state lock file under rootdir.
func SnapStateLockFileUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "state.lock")
}
// SnapModeenvFileUnder returns the path to the modeenv file under rootdir.
func SnapModeenvFileUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "modeenv")
}
// FeaturesDirUnder returns the path to the features dir under rootdir.
func FeaturesDirUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "features")
}
// SnapSystemParamsUnder returns the path to the system-params file under rootdir.
func SnapSystemParamsUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "system-params")
}
// SnapSystemdConfDirUnder returns the path to the systemd conf dir under
// rootdir.
func SnapSystemdConfDirUnder(rootdir string) string {
return filepath.Join(rootdir, "/etc/systemd/system.conf.d")
}
// SnapSystemdConfDirUnder returns the path to the systemd conf dir under
// rootdir.
func SnapServicesDirUnder(rootdir string) string {
return filepath.Join(rootdir, "/etc/systemd/system")
}
// SnapBootAssetsDirUnder returns the path to boot assets directory under a
// rootdir.
func SnapBootAssetsDirUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "boot-assets")
}
// SnapDeviceDirUnder returns the path to device directory under rootdir.
func SnapDeviceDirUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "device")
}
// SnapFDEDirUnder returns the path to full disk encryption state directory
// under rootdir.
func SnapFDEDirUnder(rootdir string) string {
return filepath.Join(SnapDeviceDirUnder(rootdir), "fde")
}
// SnapSaveDirUnder returns the path to device save directory under rootdir.
func SnapSaveDirUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "save")
}
// SnapFDEDirUnderSave returns the path to full disk encryption state directory
// inside the given save tree dir.
func SnapFDEDirUnderSave(savedir string) string {
return filepath.Join(savedir, "device/fde")
}
// SnapSaveDirUnder returns the path to device save directory under rootdir.
func SnapRepairConfigFileUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "repair.json")
}
// SnapKernelTreesDirUnder returns the path to the snap kernel drivers trees
// dir under rootdir.
func SnapKernelDriversTreesDirUnder(rootdir string) string {
return filepath.Join(rootdir, snappyDir, "kernel")
}
// AddRootDirCallback registers a callback for whenever the global root
// directory (set by SetRootDir) is changed to enable updates to variables in
// other packages that depend on its location.
func AddRootDirCallback(c func(string)) {
callbacks = append(callbacks, c)
}
// SetRootDir allows settings a new global root directory, this is useful
// for e.g. chroot operations
func SetRootDir(rootdir string) {
if rootdir == "" {
rootdir = "/"
}
GlobalRootDir = rootdir
altDirDistros := []string{
"altlinux",
"antergos",
"arch",
"archlinux",
"fedora",
"gentoo",
"manjaro",
"manjaro-arm",
}
isInsideBase, _ := isInsideBaseSnap()
if !isInsideBase && release.DistroLike(altDirDistros...) {
SnapMountDir = filepath.Join(rootdir, "/var/lib/snapd/snap")
} else {
SnapMountDir = filepath.Join(rootdir, defaultSnapMountDir)
}
SnapDataDir = filepath.Join(rootdir, "/var/snap")
SnapAppArmorDir = filepath.Join(rootdir, snappyDir, "apparmor", "profiles")
SnapDownloadCacheDir = filepath.Join(rootdir, snappyDir, "cache")
SnapSeccompBase = filepath.Join(rootdir, snappyDir, "seccomp")
SnapSeccompDir = filepath.Join(SnapSeccompBase, "bpf")
SnapMountPolicyDir = filepath.Join(rootdir, snappyDir, "mount")
SnapCgroupPolicyDir = filepath.Join(rootdir, snappyDir, "cgroup")
SnapdMaintenanceFile = filepath.Join(rootdir, snappyDir, "maintenance.json")
SnapBlobDir = SnapBlobDirUnder(rootdir)
SnapVoidDir = filepath.Join(rootdir, snappyDir, "void")
// ${snappyDir}/desktop is added to $XDG_DATA_DIRS.
// Subdirectories are interpreted according to the relevant
// freedesktop.org specifications
SnapDesktopFilesDir = filepath.Join(rootdir, snappyDir, "desktop", "applications")
SnapDesktopIconsDir = filepath.Join(rootdir, snappyDir, "desktop", "icons")
RunDir = filepath.Join(rootdir, "/run")
SnapRunDir = filepath.Join(rootdir, "/run/snapd")
SnapRunNsDir = filepath.Join(SnapRunDir, "/ns")
SnapRunLockDir = filepath.Join(SnapRunDir, "/lock")
SnapBootstrapRunDir = filepath.Join(SnapRunDir, "snap-bootstrap")
SnapdStoreSSLCertsDir = filepath.Join(rootdir, snappyDir, "ssl/store-certs")
// keep in sync with the debian/snapd.socket file:
SnapdSocket = filepath.Join(rootdir, "/run/snapd.socket")
SnapSocket = filepath.Join(rootdir, "/run/snapd-snap.socket")
SnapAssertsDBDir = filepath.Join(rootdir, snappyDir, "assertions")
SnapCookieDir = filepath.Join(rootdir, snappyDir, "cookie")
SnapAssertsSpoolDir = filepath.Join(rootdir, "run/snapd/auto-import")
SnapSeqDir = filepath.Join(rootdir, snappyDir, "sequence")
SnapStateFile = SnapStateFileUnder(rootdir)
SnapStateLockFile = SnapStateLockFileUnder(rootdir)
SnapSystemKeyFile = filepath.Join(rootdir, snappyDir, "system-key")
SnapCacheDir = filepath.Join(rootdir, "/var/cache/snapd")
SnapNamesFile = filepath.Join(SnapCacheDir, "names")
SnapSectionsFile = filepath.Join(SnapCacheDir, "sections")
SnapCommandsDB = filepath.Join(SnapCacheDir, "commands.db")
SnapAuxStoreInfoDir = filepath.Join(SnapCacheDir, "aux")
SnapSeedDir = SnapSeedDirUnder(rootdir)
SnapDeviceDir = SnapDeviceDirUnder(rootdir)
SnapModeenvFile = SnapModeenvFileUnder(rootdir)
SnapBootAssetsDir = SnapBootAssetsDirUnder(rootdir)
SnapFDEDir = SnapFDEDirUnder(rootdir)
SnapSaveDir = SnapSaveDirUnder(rootdir)
SnapDeviceSaveDir = filepath.Join(SnapSaveDir, "device")
SnapDataSaveDir = filepath.Join(SnapSaveDir, "snap")
SnapRepairConfigFile = SnapRepairConfigFileUnder(rootdir)
SnapRepairDir = filepath.Join(rootdir, snappyDir, "repair")
SnapRepairStateFile = filepath.Join(SnapRepairDir, "repair.json")
SnapRepairRunDir = filepath.Join(SnapRepairDir, "run")
SnapRepairAssertsDir = filepath.Join(SnapRepairDir, "assertions")
SnapRunRepairDir = filepath.Join(SnapRunDir, "repair")
SnapRollbackDir = filepath.Join(rootdir, snappyDir, "rollback")
SnapBinariesDir = filepath.Join(SnapMountDir, "bin")
SnapServicesDir = filepath.Join(rootdir, "/etc/systemd/system")
SnapRuntimeServicesDir = filepath.Join(rootdir, "/run/systemd/system")
SnapUserServicesDir = filepath.Join(rootdir, "/etc/systemd/user")
SnapSystemdConfDir = SnapSystemdConfDirUnder(rootdir)
SnapSystemdDir = filepath.Join(rootdir, "/etc/systemd")
SnapSystemdRunDir = filepath.Join(rootdir, "/run/systemd")
SnapDBusSystemPolicyDir = filepath.Join(rootdir, "/etc/dbus-1/system.d")
SnapDBusSessionPolicyDir = filepath.Join(rootdir, "/etc/dbus-1/session.d")
// Use 'dbus-1/services' and `dbus-1/system-services' to mirror
// '/usr/share/dbus-1' hierarchy.
SnapDBusSessionServicesDir = filepath.Join(rootdir, snappyDir, "dbus-1", "services")
SnapDBusSystemServicesDir = filepath.Join(rootdir, snappyDir, "dbus-1", "system-services")
SnapPolkitPolicyDir = filepath.Join(rootdir, "/usr/share/polkit-1/actions")
CloudInstanceDataFile = filepath.Join(rootdir, "/run/cloud-init/instance-data.json")
SnapUdevRulesDir = filepath.Join(rootdir, "/etc/udev/rules.d")
SnapKModModulesDir = filepath.Join(rootdir, "/etc/modules-load.d/")
SnapKModModprobeDir = filepath.Join(rootdir, "/etc/modprobe.d/")
LocaleDir = filepath.Join(rootdir, "/usr/share/locale")
ClassicDir = filepath.Join(rootdir, "/writable/classic")
opensuseTWWithLibexec := func() bool {
// XXX: this is pretty naive if openSUSE ever starts going back
// and forth about the change
if !release.DistroLike("opensuse-tumbleweed") {
return false
}
v, err := strconv.Atoi(release.ReleaseInfo.VersionID)
if err != nil {
// nothing we can do here
return false
}
// first seen on snapshot "20200826"
if v < 20200826 {
return false
}
return true
}
if release.DistroLike("fedora") || opensuseTWWithLibexec() {
// RHEL, CentOS, Fedora and derivatives, some more recent
// snapshots of openSUSE Tumbleweed;
// both RHEL and CentOS list "fedora" in ID_LIKE
DistroLibExecDir = filepath.Join(rootdir, "/usr/libexec/snapd")
} else {
DistroLibExecDir = filepath.Join(rootdir, "/usr/lib/snapd")
}
XdgRuntimeDirBase = filepath.Join(rootdir, "/run/user")
XdgRuntimeDirGlob = filepath.Join(XdgRuntimeDirBase, "*/")
CompletionHelperInCore = filepath.Join(CoreLibExecDir, "etelpmoc.sh")
BashCompletionScript = filepath.Join(rootdir, "/usr/share/bash-completion/bash_completion")
LegacyCompletersDir = filepath.Join(rootdir, "/usr/share/bash-completion/completions/")
CompletersDir = filepath.Join(rootdir, snappyDir, "desktop/bash-completion/completions/")
// These paths agree across all supported distros
SystemFontsDir = filepath.Join(rootdir, "/usr/share/fonts")
SystemLocalFontsDir = filepath.Join(rootdir, "/usr/local/share/fonts")
// The cache path is true for Ubuntu, Debian, openSUSE, Arch
SystemFontconfigCacheDirs = []string{filepath.Join(rootdir, "/var/cache/fontconfig")}
if release.DistroLike("fedora") && !release.DistroLike("amzn") {
// Applies to Fedora and CentOS, Amazon Linux 2 is behind with
// updates to fontconfig and uses /var/cache/fontconfig instead,
// see:
// https://fedoraproject.org/wiki/Changes/FontconfigCacheDirChange
// https://bugzilla.redhat.com/show_bug.cgi?id=1416380
// https://bugzilla.redhat.com/show_bug.cgi?id=1377367
//
// However, snaps may still use older libfontconfig, which fails
// to parse the new config and defaults to
// /var/cache/fontconfig. In this case we need to make both
// locations available
SystemFontconfigCacheDirs = append(SystemFontconfigCacheDirs, filepath.Join(rootdir, "/usr/lib/fontconfig/cache"))
}
SnapshotsDir = filepath.Join(rootdir, snappyDir, "snapshots")
SysfsDir = filepath.Join(rootdir, "/sys")
FeaturesDir = FeaturesDirUnder(rootdir)
// If the root directory changes we also need to reset snapHomeDirs.
SetSnapHomeDirs("/home")
// call the callbacks last so that the callbacks can just reference the
// global vars if they want, instead of using the new rootdir directly
for _, c := range callbacks {
c(rootdir)
}
}
// what inside a (non-classic) snap is /usr/lib/snapd, outside can come from different places
func libExecOutside(base string) string {
if base == "" {
// no explicit base; core is it
return filepath.Join(SnapMountDir, "core/current/usr/lib/snapd")
}
// if a base is set, libexec comes from the snapd snap if it's
// installed, and otherwise from the distro.
p := filepath.Join(SnapMountDir, "snapd/current/usr/lib/snapd")
if st, err := os.Stat(p); err == nil && st.IsDir() {
return p
}
return DistroLibExecDir
}
func CompleteShPath(base string) string {
return filepath.Join(libExecOutside(base), "complete.sh")
}
func IsCompleteShSymlink(compPath string) bool {
target, err := os.Readlink(compPath)
// check if the target paths ends with "/snapd/complete.sh"
return err == nil && filepath.Base(filepath.Dir(target)) == "snapd" && filepath.Base(target) == "complete.sh"
}