Initial commit

Proof-of-concept implementation. Bugs will occur.

internal/domains/filesystem/file.go

@@ -0,0 +1,75 @@
+package filesystem
+
+import (
+	"context"
+	"io"
+	"os"
+	"sync"
+	"syscall"
+
+	"github.com/hanwen/go-fuse/v2/fs"
+	"github.com/hanwen/go-fuse/v2/fuse"
+)
+
+type File struct {
+	file      *os.File
+	fileMutex sync.Mutex
+}
+
+var (
+	_ = (fs.FileReader)((*File)(nil))
+	_ = (fs.FileWriter)((*File)(nil))
+	_ = (fs.FileFlusher)((*File)(nil))
+	_ = (fs.FileReleaser)((*File)(nil))
+)
+
+func (fi *File) Read(ctx context.Context, dest []byte, off int64) (fuse.ReadResult, syscall.Errno) {
+	fi.fileMutex.Lock()
+	defer fi.fileMutex.Unlock()
+
+	_, err := fi.file.Seek(off, io.SeekStart)
+	if err != nil {
+		return nil, syscall.EIO
+	}
+
+	n, err := fi.file.Read(dest)
+	if err != nil && err != io.EOF {
+		return nil, syscall.EIO
+	}
+
+	return fuse.ReadResultData(dest[:n]), 0
+}
+
+func (fi *File) Write(ctx context.Context, data []byte, off int64) (written uint32, errno syscall.Errno) {
+	fi.fileMutex.Lock()
+	defer fi.fileMutex.Unlock()
+
+	n, err := fi.file.WriteAt(data, off)
+	if err != nil {
+		return 0, syscall.EIO
+	}
+
+	return uint32(n), 0
+}
+
+func (fi *File) Flush(ctx context.Context) syscall.Errno {
+	fi.fileMutex.Lock()
+	defer fi.fileMutex.Unlock()
+
+	if err := fi.file.Sync(); err != nil {
+		return syscall.EIO
+	}
+
+	return 0
+}
+
+func (fi *File) Release(ctx context.Context) syscall.Errno {
+	fi.fileMutex.Lock()
+	defer fi.fileMutex.Unlock()
+
+	if err := fi.file.Close(); err != nil {
+		return syscall.EIO
+	}
+
+	return 0
+}