move gotd fork into repo. (#111)

- update to latest telegram layer
- remove some references to fields in tg.Entities that don't exist in
the schema
- originally added here:
https://github.com/beeper/td/commit/820929062a2ba0104397bc01235ab58a9cff780e
  - referenced here
-
https://github.com/mautrix/telegramgo/commit/124f0967ed195b5a380c9bd02e170ada9710dde3
-
https://github.com/mautrix/telegramgo/commit/4205047aab2e0639217148b5d125bfaab668bd8e

pkg/gotd/session/storage_mem.go

@@ -0,0 +1,99 @@
+package session
+
+import (
+	"context"
+	"io"
+	"os"
+	"sync"
+
+	"github.com/go-faster/errors"
+)
+
+// StorageMemory implements in-memory session storage.
+// Goroutine-safe.
+type StorageMemory struct {
+	mux  sync.RWMutex
+	data []byte
+}
+
+// Dump dumps raw session data to the given writer.
+// Returns ErrNotFound if storage is nil or if underlying session is empty.
+func (s *StorageMemory) Dump(w io.Writer) error {
+	if s == nil {
+		return ErrNotFound
+	}
+	s.mux.RLock()
+	defer s.mux.RUnlock()
+
+	if len(s.data) == 0 {
+		return ErrNotFound
+	}
+
+	if _, err := w.Write(s.data); err != nil {
+		return errors.Wrap(err, "write session")
+	}
+
+	return nil
+}
+
+// WriteFile dumps raw session data to the named file, creating it if necessary.
+// Returns ErrNotFound if storage is nil or if underlying session is empty.
+func (s *StorageMemory) WriteFile(name string, perm os.FileMode) error {
+	data, err := s.Bytes(nil)
+	if err != nil {
+		return err
+	}
+	return os.WriteFile(name, data, perm)
+}
+
+// Bytes appends raw session data to the given slice.
+// Returns ErrNotFound if storage is nil or if underlying session is empty.
+func (s *StorageMemory) Bytes(to []byte) ([]byte, error) {
+	if s == nil {
+		return nil, ErrNotFound
+	}
+	s.mux.RLock()
+	defer s.mux.RUnlock()
+
+	if len(s.data) == 0 {
+		return nil, ErrNotFound
+	}
+
+	return append(to, s.data...), nil
+}
+
+// Clone creates a clone of existing StorageMemory,
+func (s *StorageMemory) Clone() *StorageMemory {
+	s2 := &StorageMemory{}
+
+	s2.data, _ = s.Bytes(s2.data)
+	return s2
+}
+
+// LoadSession loads session from memory.
+func (s *StorageMemory) LoadSession(context.Context) ([]byte, error) {
+	if s == nil {
+		return nil, ErrNotFound
+	}
+	s.mux.RLock()
+	defer s.mux.RUnlock()
+
+	if len(s.data) == 0 {
+		return nil, ErrNotFound
+	}
+	cpy := append([]byte(nil), s.data...)
+
+	return cpy, nil
+}
+
+// StoreSession stores session to memory.
+func (s *StorageMemory) StoreSession(ctx context.Context, data []byte) error {
+	if s == nil {
+		return errors.New("StoreSession called on StorageMemory(nil)")
+	}
+
+	s.mux.Lock()
+	s.data = data
+	s.mux.Unlock()
+	return nil
+}