machine refactor 3: add symlinks for sockets

to avoid errors on macos, we use symlinks to long socket names.

Fixes: containers#12751
Fixes: containers#13609

Signed-off-by: Brent Baude <bbaude@redhat.com>

[NO NEW TESTS NEEDED]

Signed-off-by: Brent Baude <bbaude@redhat.com>

pkg/machine/qemu/config.go

@@ -197,8 +197,11 @@ func NewMachineFile(path string, symlink *string) (*MachineFile, error) {
 	if symlink != nil && len(*symlink) < 1 {
 		return nil, errors.New("invalid symlink path")
 	}
-	return &MachineFile{
-		Path:    path,
-		Symlink: symlink,
-	}, nil
+	mf := MachineFile{Path: path}
+	if symlink != nil {
+		if err := mf.makeSymlink(symlink); err != nil {
+			return nil, err
+		}
+	}
+	return &mf, nil
 }

pkg/machine/qemu/machine.go

@@ -131,10 +131,11 @@ func (p *Provider) NewMachine(opts machine.InitOptions) (machine.VM, error) {
 	// Add serial port for readiness
 	cmd = append(cmd, []string{
 		"-device", "virtio-serial",
-		"-chardev", "socket,path=" + vm.getReadySocket() + ",server=on,wait=off,id=" + vm.Name + "_ready",
+		// qemu needs to establish the long name; other connections can use the symlink'd
+		"-chardev", "socket,path=" + vm.ReadySocket.Path + ",server=on,wait=off,id=" + vm.Name + "_ready",
 		"-device", "virtserialport,chardev=" + vm.Name + "_ready" + ",name=org.fedoraproject.port.0"}...)
 	vm.CmdLine = cmd
-	if err := vm.setQEMUAndPIDSocket(); err != nil {
+	if err := vm.setPIDSocket(); err != nil {
 		return nil, err
 	}
 	return vm, nil
@@ -487,9 +488,6 @@ func (v *MachineVM) Start(name string, _ machine.StartOptions) error {
 			return err
 		}
 	}
-	if err := v.setQEMUAndPIDSocket(); err != nil {
-		return err
-	}
 	// If the qemusocketpath exists and the vm is off/down, we should rm
 	// it before the dial as to avoid a segv
 	if err := v.QMPMonitor.Address.Delete(); err != nil {
@@ -700,7 +698,7 @@ func (v *MachineVM) Stop(_ string, _ machine.StopOptions) error {
 		return err
 	}
 
-	if _, err := os.Stat(v.getPidFile()); os.IsNotExist(err) {
+	if _, err := os.Stat(v.PidFilePath.GetPath()); os.IsNotExist(err) {
 		return nil
 	}
 	pidString, err := v.PidFilePath.Read()
@@ -748,7 +746,7 @@ func (v *MachineVM) Stop(_ string, _ machine.StopOptions) error {
 		waitInternal = waitInternal * 2
 	}
 
-	return nil
+	return v.ReadySocket.Delete()
 }
 
 // NewQMPMonitor creates the monitor subsection of our vm
@@ -770,7 +768,7 @@ func NewQMPMonitor(network, name string, timeout time.Duration) (Monitor, error)
 	if timeout == 0 {
 		timeout = defaultQMPTimeout
 	}
-	address, err := NewMachineFile(filepath.Join(rtDir, "qmp+"+name+".sock"), nil)
+	address, err := NewMachineFile(filepath.Join(rtDir, "qmp_"+name+".sock"), nil)
 	if err != nil {
 		return Monitor{}, err
 	}
@@ -831,7 +829,6 @@ func (v *MachineVM) Remove(_ string, opts machine.RemoveOptions) (string, func()
 		confirmationMessage += msg + "\n"
 	}
 
-	//silently try to delete socket and pid file
 	//remove socket and pid file if any: warn at low priority if things fail
 	// Remove the pidfile
 	if err := v.PidFilePath.Delete(); err != nil {
@@ -1083,7 +1080,7 @@ func (v *MachineVM) startHostNetworking() (string, apiForwardingState, error) {
 	files := []*os.File{os.Stdin, os.Stdout, os.Stderr}
 	attr.Files = files
 	cmd := []string{binary}
-	cmd = append(cmd, []string{"-listen-qemu", fmt.Sprintf("unix://%s", v.getQMPMonitorSocket()), "-pid-file", v.getPidFile()}...)
+	cmd = append(cmd, []string{"-listen-qemu", fmt.Sprintf("unix://%s", v.QMPMonitor.Address.GetPath()), "-pid-file", v.PidFilePath.GetPath()}...)
 	// Add the ssh port
 	cmd = append(cmd, []string{"-ssh-port", fmt.Sprintf("%d", v.Port)}...)
 
@@ -1187,36 +1184,38 @@ func (v *MachineVM) setConfigPath() error {
 }
 
 func (v *MachineVM) setReadySocket() error {
+	readySocketName := v.Name + "_ready.sock"
 	rtPath, err := getRuntimeDir()
 	if err != nil {
 		return err
 	}
-	virtualSocketPath, err := NewMachineFile(filepath.Join(rtPath, "podman", v.Name+"_ready.sock"), nil)
+	virtualSocketPath, err := NewMachineFile(filepath.Join(rtPath, "podman", readySocketName), &readySocketName)
 	if err != nil {
 		return err
 	}
 	v.ReadySocket = *virtualSocketPath
 	return nil
 }
 
-func (v *MachineVM) setQEMUAndPIDSocket() error {
+func (v *MachineVM) setPIDSocket() error {
 	rtPath, err := getRuntimeDir()
 	if err != nil {
 		return err
 	}
 	if !rootless.IsRootless() {
 		rtPath = "/run"
 	}
+	pidFileName := fmt.Sprintf("%s.pid", v.Name)
 	socketDir := filepath.Join(rtPath, "podman")
-	pidFilePath, err := NewMachineFile(filepath.Join(socketDir, fmt.Sprintf("%s.pid", v.Name)), nil)
+	pidFilePath, err := NewMachineFile(filepath.Join(socketDir, pidFileName), &pidFileName)
 	if err != nil {
 		return err
 	}
 	v.PidFilePath = *pidFilePath
 	return nil
 }
 
-// Deprecated: getSocketandPid is being replace by setQEMUAndPIDSocket and
+// Deprecated: getSocketandPid is being replace by setPIDSocket and
 // machinefiles.
 func (v *MachineVM) getSocketandPid() (string, string, error) {
 	rtPath, err := getRuntimeDir()
@@ -1342,7 +1341,7 @@ func (v *MachineVM) update() error {
 	}
 	b, err := v.ConfigPath.Read()
 	if err != nil {
-		if os.IsNotExist(err) {
+		if errors.Is(err, os.ErrNotExist) {
 			return errors.Wrap(machine.ErrNoSuchVM, v.Name)
 		}
 		return err
@@ -1377,30 +1376,13 @@ func (v *MachineVM) writeConfig() error {
 	return nil
 }
 
-// getPidFile gets the file where the machine pid is stored
-func (v *MachineVM) getPidFile() string {
-	return v.PidFilePath.GetPath()
-}
-
-// getQMPMonitorSocket gets the socket used by qemu to interact
-// with the instance
-func (v *MachineVM) getQMPMonitorSocket() string {
-	return v.QMPMonitor.Address.GetPath()
-}
-
-// getReadySocket returns the socket used to communicate
-// with the machinevm and report when it is booted
-func (v *MachineVM) getReadySocket() string {
-	return v.ReadySocket.GetPath()
-}
-
-// getImageFile returns the path to the image used
+// getImageFile wrapper returns the path to the image used
 // to boot the VM
 func (v *MachineVM) getImageFile() string {
 	return v.ImagePath.GetPath()
 }
 
-// getIgnitionFile returns the path to the ignition file
+// getIgnitionFile wrapper returns the path to the ignition file
 func (v *MachineVM) getIgnitionFile() string {
 	return v.IgnitionFilePath.GetPath()
 }

pkg/machine/qemu/options_darwin.go

@@ -2,6 +2,7 @@ package qemu
 
 import (
 	"os"
+	"path/filepath"
 )
 
 func getRuntimeDir() (string, error) {
@@ -11,3 +12,15 @@ func getRuntimeDir() (string, error) {
 	}
 	return tmpDir, nil
 }
+
+// makeSymlink for macOS creates a symlink in $HOME/.podman/
+// for a machinefile like a socket
+func (m *MachineFile) makeSymlink(symlink *string) error {
+	homedir, err := os.UserHomeDir()
+	if err != nil {
+		return err
+	}
+	sl := filepath.Join(homedir, ".podman", *symlink)
+	m.Symlink = &sl
+	return os.Symlink(m.Path, sl)
+}

pkg/machine/qemu/options_linux.go

@@ -11,3 +11,8 @@ func getRuntimeDir() (string, error) {
 	}
 	return util.GetRuntimeDir()
 }
+
+// makeSymlink is a no-op for Linux
+func (m *MachineFile) makeSymlink(*string) error {
+	return nil
+}