add staged in status

src/utils/index.rs

@@ -0,0 +1,27 @@
+use std::fs::OpenOptions;
+use std::fs::File;
+use std::path::PathBuf;
+use crate::utils::read;
+use std::io;
+
+pub fn read_only(mut path: PathBuf) -> File {
+    path.push("index");
+    OpenOptions::new()
+        .read(true)
+        .open(path).expect("Cannot open index file")
+}
+
+pub fn open(mut path: PathBuf) -> File {
+    path.push("index");
+    OpenOptions::new()
+        .read(true)
+        .write(true)
+        .append(true)
+        .create(true)
+        .open(path).expect("Cannot open index file")
+}
+
+pub fn read_line(mut path: PathBuf) -> io::Result<io::Lines<io::BufReader<File>>> {
+    path.push("index");
+    read::read_lines(path)
+}