src/backup/index.rs: add compute_csum

And use it for fixed and dynamic index. Please note that this
changes checksums for fixed indexes, so restore older backups
will fails now (not backward compatible).

src/backup/dynamic_index.rs

@@ -141,24 +141,6 @@ impl DynamicIndexReader {
         &self.index[pos].digest
     }
 
-    /// Compute checksum and data size
-    pub fn compute_csum(&self) -> ([u8; 32], u64) {
-        let mut csum = openssl::sha::Sha256::new();
-        for entry in &self.index {
-            csum.update(&entry.end_le.to_ne_bytes());
-            csum.update(&entry.digest);
-        }
-        let csum = csum.finish();
-
-        (
-            csum,
-            self.index
-                .last()
-                .map(|entry| entry.end())
-                .unwrap_or(0)
-        )
-    }
-
     // TODO: can we use std::slice::binary_search with Mmap now?
     fn binary_search(
         &self,

src/backup/fixed_index.rs

@@ -1,5 +1,4 @@
 use anyhow::{bail, format_err, Error};
-use std::convert::TryInto;
 use std::io::{Seek, SeekFrom};
 
 use super::chunk_stat::*;
@@ -147,15 +146,6 @@ impl FixedIndexReader {
         Ok(())
     }
 
-    #[inline]
-    fn chunk_digest(&self, pos: usize) -> &[u8; 32] {
-        if pos >= self.index_length {
-            panic!("chunk index out of range");
-        }
-        let slice = unsafe { std::slice::from_raw_parts(self.index.add(pos * 32), 32) };
-        slice.try_into().unwrap()
-    }
-
     #[inline]
     fn chunk_end(&self, pos: usize) -> u64 {
         if pos >= self.index_length {
@@ -170,20 +160,6 @@ impl FixedIndexReader {
         }
     }
 
-    /// Compute checksum and data size
-    pub fn compute_csum(&self) -> ([u8; 32], u64) {
-        let mut csum = openssl::sha::Sha256::new();
-        let mut chunk_end = 0;
-        for pos in 0..self.index_length {
-            chunk_end = self.chunk_end(pos);
-            let digest = self.chunk_digest(pos);
-            csum.update(digest);
-        }
-        let csum = csum.finish();
-
-        (csum, chunk_end)
-    }
-
     pub fn print_info(&self) {
         println!("Size: {}", self.size);
         println!("ChunkSize: {}", self.chunk_size);

src/backup/index.rs

@@ -22,6 +22,21 @@ pub trait IndexFile {
     fn index_bytes(&self) -> u64;
     fn chunk_info(&self, pos: usize) -> Option<ChunkReadInfo>;
 
+    /// Compute index checksum and size
+    fn compute_csum(&self) -> ([u8; 32], u64) {
+        let mut csum = openssl::sha::Sha256::new();
+        let mut chunk_end = 0;
+        for pos in 0..self.index_count() {
+            let info = self.chunk_info(pos).unwrap();
+            chunk_end = info.range.end;
+            csum.update(&chunk_end.to_le_bytes());
+            csum.update(&info.digest);
+        }
+        let csum = csum.finish();
+
+        (csum, chunk_end)
+    }
+
     /// Returns most often used chunks
     fn find_most_used_chunks(&self, max: usize) -> HashMap<[u8; 32], usize> {
         let mut map = HashMap::new();