tag: hide constructor details for Tags structure

Signed-off-by: Zhouqi Jiang <luojia@hust.edu.cn>

Author: luojia65

src/de.rs

@@ -87,12 +87,11 @@ impl DeviceTree {
         let structure_len = u32::from_be(self.header.size_dt_struct) as usize;
         let strings_addr = (u32::from_be(self.header.off_dt_strings) - HEADER_LEN) as usize;
         let strings_len = u32::from_be(self.header.size_dt_strings) as usize;
-        Tags {
-            structure: &self.data[structure_addr..structure_addr + structure_len],
-            string_table: &self.data[strings_addr..strings_addr + strings_len],
-            cur: 0,
-            offset_from_file_begin: structure_addr,
-        }
+        Tags::new(
+            &self.data[structure_addr..structure_addr + structure_len],
+            &self.data[strings_addr..strings_addr + strings_len],
+            structure_addr,
+        )
     }
 }
 

src/tag.rs

@@ -3,10 +3,21 @@ use crate::error::{Error, Result};
 
 #[derive(Debug, Clone)]
 pub struct Tags<'a> {
-    pub(crate) structure: &'a [u8],
-    pub(crate) string_table: &'a [u8],
-    pub(crate) cur: usize,
-    pub(crate) offset_from_file_begin: usize,
+    structure: &'a [u8],
+    string_table: &'a [u8],
+    cur: usize,
+    offset_from_file_begin: usize,
+}
+
+impl<'a> Tags<'a> {
+    pub fn new(structure: &'a [u8], string_table: &'a [u8], offset_from_file_begin: usize) -> Self {
+        Tags {
+            structure,
+            string_table,
+            cur: 0,
+            offset_from_file_begin,
+        }
+    }
 }
 
 #[inline]