state: rename simple store implementation

Signed-off-by: Ophestra Umiker <cat@ophivana.moe>

1 files changed, 0 insertions, 222 deletions

diff --git a/internal/state/simple.go b/internal/state/simple.go
deleted file mode 100644
index 1a26f6f7..00000000
--- a/internal/state/simple.go
+++ /dev/null
@@ -1,222 +0,0 @@
-package state
-
-import (
-	"encoding/gob"
-	"errors"
-	"io/fs"
-	"os"
-	"path"
-	"strconv"
-	"sync"
-	"syscall"
-)
-
-// file-based locking
-type simpleStore struct {
-	path []string
-
-	// created/opened by prepare
-	lockfile *os.File
-	// enforce prepare method
-	init sync.Once
-	// error returned by prepare
-	initErr error
-
-	lock sync.Mutex
-}
-
-func (s *simpleStore) Do(f func(b Backend)) (bool, error) {
-	s.init.Do(s.prepare)
-	if s.initErr != nil {
-		return false, s.initErr
-	}
-
-	s.lock.Lock()
-	defer s.lock.Unlock()
-
-	// lock store
-	if err := s.lockFile(); err != nil {
-		return false, err
-	}
-
-	// initialise new backend for caller
-	b := new(simpleBackend)
-	b.path = path.Join(s.path...)
-	f(b)
-	// disable backend
-	b.lock.Lock()
-
-	// unlock store
-	return true, s.unlockFile()
-}
-
-func (s *simpleStore) lockFileAct(lt int) (err error) {
-	op := "LockAct"
-	switch lt {
-	case syscall.LOCK_EX:
-		op = "Lock"
-	case syscall.LOCK_UN:
-		op = "Unlock"
-	}
-
-	for {
-		err = syscall.Flock(int(s.lockfile.Fd()), lt)
-		if !errors.Is(err, syscall.EINTR) {
-			break
-		}
-	}
-	if err != nil {
-		return &fs.PathError{
-			Op:   op,
-			Path: s.lockfile.Name(),
-			Err:  err,
-		}
-	}
-	return nil
-}
-
-func (s *simpleStore) lockFile() error {
-	return s.lockFileAct(syscall.LOCK_EX)
-}
-
-func (s *simpleStore) unlockFile() error {
-	return s.lockFileAct(syscall.LOCK_UN)
-}
-
-func (s *simpleStore) prepare() {
-	s.initErr = func() error {
-		prefix := path.Join(s.path...)
-		// ensure directory
-		if err := os.MkdirAll(prefix, 0700); err != nil && !errors.Is(err, fs.ErrExist) {
-			return err
-		}
-
-		// open locker file
-		if f, err := os.OpenFile(prefix+".lock", os.O_RDWR|os.O_CREATE, 0600); err != nil {
-			return err
-		} else {
-			s.lockfile = f
-		}
-
-		return nil
-	}()
-}
-
-func (s *simpleStore) Close() error {
-	s.lock.Lock()
-	defer s.lock.Unlock()
-
-	err := s.lockfile.Close()
-	if err == nil || errors.Is(err, os.ErrInvalid) || errors.Is(err, os.ErrClosed) {
-		return nil
-	}
-	return err
-}
-
-type simpleBackend struct {
-	path string
-
-	lock sync.RWMutex
-}
-
-func (b *simpleBackend) filename(pid int) string {
-	return path.Join(b.path, strconv.Itoa(pid))
-}
-
-// reads all launchers in simpleBackend
-// file contents are ignored if decode is false
-func (b *simpleBackend) load(decode bool) ([]*State, error) {
-	b.lock.RLock()
-	defer b.lock.RUnlock()
-
-	var (
-		r []*State
-		f *os.File
-	)
-
-	// read directory contents, should only contain files named after PIDs
-	if pl, err := os.ReadDir(b.path); err != nil {
-		return nil, err
-	} else {
-		for _, e := range pl {
-			// run in a function to better handle file closing
-			if err = func() error {
-				// open state file for reading
-				if f, err = os.Open(path.Join(b.path, e.Name())); err != nil {
-					return err
-				} else {
-					defer func() {
-						if f.Close() != nil {
-							// unreachable
-							panic("foreign state file closed prematurely")
-						}
-					}()
-
-					var s State
-					r = append(r, &s)
-
-					// append regardless, but only parse if required, used to implement Len
-					if decode {
-						return gob.NewDecoder(f).Decode(&s)
-					} else {
-						return nil
-					}
-				}
-			}(); err != nil {
-				return nil, err
-			}
-		}
-	}
-
-	return r, nil
-}
-
-// Save writes process state to filesystem
-func (b *simpleBackend) Save(state *State) error {
-	b.lock.Lock()
-	defer b.lock.Unlock()
-
-	if state.Config == nil {
-		return errors.New("state does not contain config")
-	}
-
-	statePath := b.filename(state.PID)
-
-	// create and open state data file
-	if f, err := os.OpenFile(statePath, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600); err != nil {
-		return err
-	} else {
-		defer func() {
-			if f.Close() != nil {
-				// unreachable
-				panic("state file closed prematurely")
-			}
-		}()
-		// encode into state file
-		return gob.NewEncoder(f).Encode(state)
-	}
-}
-
-func (b *simpleBackend) Destroy(pid int) error {
-	b.lock.Lock()
-	defer b.lock.Unlock()
-
-	return os.Remove(b.filename(pid))
-}
-
-func (b *simpleBackend) Load() ([]*State, error) {
-	return b.load(true)
-}
-
-func (b *simpleBackend) Len() (int, error) {
-	// rn consists of only nil entries but has the correct length
-	rn, err := b.load(false)
-	return len(rn), err
-}
-
-// NewSimple returns an instance of a file-based store.
-func NewSimple(runDir string, prefix ...string) Store {
-	b := new(simpleStore)
-	b.path = append([]string{runDir, "state"}, prefix...)
-	return b
-}