1 files changed, 0 insertions, 373 deletions
diff --git a/internal/state/multi.go b/internal/state/multi.go
deleted file mode 100644
index fac5b389..00000000
--- a/internal/state/multi.go
+++ /dev/null
@@ -1,373 +0,0 @@
-package state
-
-import (
-	"encoding/binary"
-	"encoding/gob"
-	"errors"
-	"fmt"
-	"io"
-	"io/fs"
-	"os"
-	"path"
-	"strconv"
-	"sync"
-	"syscall"
-
-	"git.gensokyo.uk/security/hakurei/hst"
-	"git.gensokyo.uk/security/hakurei/internal/app"
-	"git.gensokyo.uk/security/hakurei/internal/hlog"
-)
-
-// fine-grained locking and access
-type multiStore struct {
-	base string
-
-	// initialised backends
-	backends *sync.Map
-
-	lock sync.RWMutex
-}
-
-func (s *multiStore) Do(aid int, f func(c Cursor)) (bool, error) {
-	s.lock.RLock()
-	defer s.lock.RUnlock()
-
-	// load or initialise new backend
-	b := new(multiBackend)
-	b.lock.Lock()
-	if v, ok := s.backends.LoadOrStore(aid, b); ok {
-		b = v.(*multiBackend)
-	} else {
-		b.path = path.Join(s.base, strconv.Itoa(aid))
-
-		// ensure directory
-		if err := os.MkdirAll(b.path, 0700); err != nil && !errors.Is(err, fs.ErrExist) {
-			s.backends.CompareAndDelete(aid, b)
-			return false, err
-		}
-
-		// open locker file
-		if l, err := os.OpenFile(b.path+".lock", os.O_RDWR|os.O_CREATE, 0600); err != nil {
-			s.backends.CompareAndDelete(aid, b)
-			return false, err
-		} else {
-			b.lockfile = l
-		}
-		b.lock.Unlock()
-	}
-
-	// lock backend
-	if err := b.lockFile(); err != nil {
-		return false, err
-	}
-
-	// expose backend methods without exporting the pointer
-	c := new(struct{ *multiBackend })
-	c.multiBackend = b
-	f(b)
-	// disable access to the backend on a best-effort basis
-	c.multiBackend = nil
-
-	// unlock backend
-	return true, b.unlockFile()
-}
-
-func (s *multiStore) List() ([]int, error) {
-	var entries []os.DirEntry
-
-	// read base directory to get all aids
-	if v, err := os.ReadDir(s.base); err != nil && !errors.Is(err, os.ErrNotExist) {
-		return nil, err
-	} else {
-		entries = v
-	}
-
-	aidsBuf := make([]int, 0, len(entries))
-	for _, e := range entries {
-		// skip non-directories
-		if !e.IsDir() {
-			hlog.Verbosef("skipped non-directory entry %q", e.Name())
-			continue
-		}
-
-		// skip non-numerical names
-		if v, err := strconv.Atoi(e.Name()); err != nil {
-			hlog.Verbosef("skipped non-aid entry %q", e.Name())
-			continue
-		} else {
-			if v < 0 || v > 9999 {
-				hlog.Verbosef("skipped out of bounds entry %q", e.Name())
-				continue
-			}
-
-			aidsBuf = append(aidsBuf, v)
-		}
-	}
-
-	return append([]int(nil), aidsBuf...), nil
-}
-
-func (s *multiStore) Close() error {
-	s.lock.Lock()
-	defer s.lock.Unlock()
-
-	var errs []error
-	s.backends.Range(func(_, value any) bool {
-		b := value.(*multiBackend)
-		errs = append(errs, b.close())
-		return true
-	})
-
-	return errors.Join(errs...)
-}
-
-type multiBackend struct {
-	path string
-
-	// created/opened by prepare
-	lockfile *os.File
-
-	lock sync.RWMutex
-}
-
-func (b *multiBackend) filename(id *app.ID) string {
-	return path.Join(b.path, id.String())
-}
-
-func (b *multiBackend) 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(b.lockfile.Fd()), lt)
-		if !errors.Is(err, syscall.EINTR) {
-			break
-		}
-	}
-	if err != nil {
-		return &fs.PathError{
-			Op:   op,
-			Path: b.lockfile.Name(),
-			Err:  err,
-		}
-	}
-	return nil
-}
-
-func (b *multiBackend) lockFile() error {
-	return b.lockFileAct(syscall.LOCK_EX)
-}
-
-func (b *multiBackend) unlockFile() error {
-	return b.lockFileAct(syscall.LOCK_UN)
-}
-
-// reads all launchers in simpleBackend
-// file contents are ignored if decode is false
-func (b *multiBackend) load(decode bool) (Entries, error) {
-	b.lock.RLock()
-	defer b.lock.RUnlock()
-
-	// read directory contents, should only contain files named after ids
-	var entries []os.DirEntry
-	if pl, err := os.ReadDir(b.path); err != nil {
-		return nil, err
-	} else {
-		entries = pl
-	}
-
-	// allocate as if every entry is valid
-	// since that should be the case assuming no external interference happens
-	r := make(Entries, len(entries))
-
-	for _, e := range entries {
-		if e.IsDir() {
-			return nil, fmt.Errorf("unexpected directory %q in store", e.Name())
-		}
-
-		id := new(app.ID)
-		if err := app.ParseAppID(id, e.Name()); err != nil {
-			return nil, err
-		}
-
-		// 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")
-					}
-				}()
-
-				s := new(State)
-				r[*id] = s
-
-				// append regardless, but only parse if required, implements Len
-				if decode {
-					if err = b.decodeState(f, s); err != nil {
-						return err
-					}
-					if s.ID != *id {
-						return fmt.Errorf("state entry %s has unexpected id %s", id, &s.ID)
-					}
-				}
-
-				return nil
-			}
-		}(); err != nil {
-			return nil, err
-		}
-	}
-
-	return r, nil
-}
-
-// state file consists of an eight byte header, followed by concatenated gobs
-// of [hst.Config] and [State], if [State.Config] is not nil or offset < 0,
-// the first gob is skipped
-func (b *multiBackend) decodeState(r io.ReadSeeker, state *State) error {
-	offset := make([]byte, 8)
-	if l, err := r.Read(offset); err != nil {
-		if errors.Is(err, io.EOF) {
-			return fmt.Errorf("state file too short: %d bytes", l)
-		}
-		return err
-	}
-
-	// decode volatile state first
-	var skipConfig bool
-	{
-		o := int64(binary.LittleEndian.Uint64(offset))
-		skipConfig = o < 0
-
-		if !skipConfig {
-			if l, err := r.Seek(o, io.SeekCurrent); err != nil {
-				return err
-			} else if l != 8+o {
-				return fmt.Errorf("invalid seek offset %d", l)
-			}
-		}
-	}
-	if err := gob.NewDecoder(r).Decode(state); err != nil {
-		return err
-	}
-
-	// decode sealed config
-	if state.Config == nil {
-		// config must be provided either as part of volatile state,
-		// or in the config segment
-		if skipConfig {
-			return ErrNoConfig
-		}
-
-		state.Config = new(hst.Config)
-		if _, err := r.Seek(8, io.SeekStart); err != nil {
-			return err
-		}
-		return gob.NewDecoder(r).Decode(state.Config)
-	} else {
-		return nil
-	}
-}
-
-// Save writes process state to filesystem
-func (b *multiBackend) Save(state *State, configWriter io.WriterTo) error {
-	b.lock.Lock()
-	defer b.lock.Unlock()
-
-	if configWriter == nil && state.Config == nil {
-		return ErrNoConfig
-	}
-
-	statePath := b.filename(&state.ID)
-
-	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")
-			}
-		}()
-		return b.encodeState(f, state, configWriter)
-	}
-}
-
-func (b *multiBackend) encodeState(w io.WriteSeeker, state *State, configWriter io.WriterTo) error {
-	offset := make([]byte, 8)
-
-	// skip header bytes
-	if _, err := w.Seek(8, io.SeekStart); err != nil {
-		return err
-	}
-
-	if configWriter != nil {
-		// write config gob and encode header
-		if l, err := configWriter.WriteTo(w); err != nil {
-			return err
-		} else {
-			binary.LittleEndian.PutUint64(offset, uint64(l))
-		}
-	} else {
-		// offset == -1 indicates absence of config gob
-		binary.LittleEndian.PutUint64(offset, 0xffffffffffffffff)
-	}
-
-	// encode volatile state
-	if err := gob.NewEncoder(w).Encode(state); err != nil {
-		return err
-	}
-
-	// write header
-	if _, err := w.Seek(0, io.SeekStart); err != nil {
-		return err
-	}
-	_, err := w.Write(offset)
-	return err
-}
-
-func (b *multiBackend) Destroy(id app.ID) error {
-	b.lock.Lock()
-	defer b.lock.Unlock()
-
-	return os.Remove(b.filename(&id))
-}
-
-func (b *multiBackend) Load() (Entries, error) {
-	return b.load(true)
-}
-
-func (b *multiBackend) Len() (int, error) {
-	// rn consists of only nil entries but has the correct length
-	rn, err := b.load(false)
-	return len(rn), err
-}
-
-func (b *multiBackend) close() error {
-	b.lock.Lock()
-	defer b.lock.Unlock()
-
-	err := b.lockfile.Close()
-	if err == nil || errors.Is(err, os.ErrInvalid) || errors.Is(err, os.ErrClosed) {
-		return nil
-	}
-	return err
-}
-
-// NewMulti returns an instance of the multi-file store.
-func NewMulti(runDir string) Store {
-	b := new(multiStore)
-	b.base = path.Join(runDir, "state")
-	b.backends = new(sync.Map)
-	return b
-}