Unseekable files need not to manipulate the offset

kernel/src/fs/inode_handle/mod.rs

@@ -48,6 +48,10 @@ impl InodeHandle_ {
             return file_io.read(writer);
         }
 
+        if !self.dentry.inode().is_seekable() {
+            return self.read_at(0, writer);
+        }
+
         let mut offset = self.offset.lock();
 
         let len = self.read_at(*offset, writer)?;
@@ -61,6 +65,10 @@ impl InodeHandle_ {
             return file_io.write(reader);
         }
 
+        if !self.dentry.inode().is_seekable() {
+            return self.write_at(0, reader);
+        }
+
         let mut offset = self.offset.lock();
 
         if self.status_flags().contains(StatusFlags::O_APPEND) {

kernel/src/fs/ramfs/fs.rs

@@ -1189,6 +1189,13 @@ impl Inode for RamInode {
         return_errno_with_message!(Errno::EINVAL, "ioctl is not supported");
     }
 
+    fn is_seekable(&self) -> bool {
+        !matches!(
+            self.typ,
+            InodeType::NamedPipe | InodeType::CharDevice | InodeType::Dir | InodeType::Socket
+        )
+    }
+
     fn extension(&self) -> Option<&Extension> {
         Some(&self.extension)
     }

kernel/src/fs/utils/inode.rs

@@ -426,6 +426,10 @@ pub trait Inode: Any + Sync + Send {
         true
     }
 
+    fn is_seekable(&self) -> bool {
+        true
+    }
+
     /// Get the extension of this inode
     fn extension(&self) -> Option<&Extension> {
         None