From 80d72a9853aa8d64c3dc5f8117fc78a50b6f6ca3 Mon Sep 17 00:00:00 2001
From: WangRunji <wangrunji0408@163.com>
Date: Wed, 7 Nov 2018 13:11:04 +0800
Subject: [PATCH] add simple File struct

---
 src/file.rs | 29 +++++++++++++++++++++++++++++
 src/lib.rs  |  1 +
 2 files changed, 30 insertions(+)
 create mode 100644 src/file.rs

diff --git a/src/file.rs b/src/file.rs
new file mode 100644
index 0000000..0796a3b
--- /dev/null
+++ b/src/file.rs
@@ -0,0 +1,29 @@
+use vfs::{INode, Result};
+use alloc::sync::Arc;
+
+pub struct File {
+    inode: Arc<INode>,
+    offset: usize,
+    readable: bool,
+    writable: bool,
+}
+
+impl File {
+    pub fn new(inode: Arc<INode>, readable: bool, writable: bool) -> Self {
+        File { inode, offset: 0, readable, writable }
+    }
+
+    pub fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
+        assert!(self.readable);
+        let len = self.inode.read_at(self.offset, buf)?;
+        self.offset += len;
+        Ok(len)
+    }
+
+    pub fn write(&mut self, buf: &[u8]) -> Result<usize> {
+        assert!(self.writable);
+        let len = self.inode.write_at(self.offset, buf)?;
+        self.offset += len;
+        Ok(len)
+    }
+}
\ No newline at end of file
diff --git a/src/lib.rs b/src/lib.rs
index 7916c8e..94ae27b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -25,6 +25,7 @@ mod util;
 mod blocked_device;
 mod vfs;
 mod sfs;
+pub mod file;
 mod structs;
 #[cfg(test)]
 mod tests;