storage: Fix 32-bit checksums (test) and update backup dir

Also added changelog entry

CHANGELOG.md

@@ -4,6 +4,10 @@ All changes in this project will be noted in this file.
 
 ## Version 0.8.1
 
+### Additions
+
+- Added support for manual repair with the `skyd repair` command
+
 ### Fixes
 
 - Fixed migration from v1 SE (released with v0.8.0-beta) to v2 SE (released in v0.8.0)

server/help_text/help

@@ -13,6 +13,9 @@ Usage: skyd [OPTION]...
 
 skyd is the Skytable database server daemon and can be used to serve database requests.
 
+Commands:
+  repair                        Check and repair any detected database storage errors
+
 Flags:
   -h, --help                    Display this help menu and exit.
   -v, --version                 Display the version number and exit.
@@ -36,5 +39,7 @@ Notes:
   - If no `--mode` is provided, we default to `dev`
   - You must provide `--auth-root-password` to set the default root password
   - To use TLS, you must provide both `--tlscert` and `--tlskey`
+  - When you run `repair`, your previous data is backed up in the `backups/` folder.
+  Restore if needed.
 
 For further assistance, refer to the official documentation here: https://docs.skytable.org

server/src/engine/storage/v2/mod.rs

@@ -168,7 +168,10 @@ pub fn restore(cfg: &Configuration) -> RuntimeResult<SELoaded> {
 
 pub fn repair() -> RuntimeResult<()> {
     // back up all files
-    let backup_dir = format!("backups/{}-before-repair-backup", util::time_now_string());
+    let backup_dir = format!(
+        "backups/{}-before-recovery-process",
+        util::time_now_string()
+    );
     context::set_dmsg("creating backup directory");
     FileSystem::create_dir_all(&backup_dir)?;
     context::set_dmsg("backing up GNS");

server/src/engine/storage/v2/raw/journal/raw/tests/mod.rs

@@ -114,7 +114,7 @@ impl_db_event!(
         checksum.update(&length_bytes);
         checksum.update(&me_bytes);
         buf.extend(&(checksum.finish().to_le_bytes())); // checksum
-        buf.extend(&(me.0.len() as u64).to_le_bytes()); // length
+        buf.extend(&length_bytes); // length
         buf.extend(me.0.as_bytes()); // payload
     },
     DbEventPop as 1,
@@ -173,7 +173,8 @@ impl RawJournalAdapter for SimpleDBJournal {
         match meta {
             EventMeta::NewKey => {
                 let checksum = u64::from_le_bytes(file.read_block()?);
-                let length = u64::from_le_bytes(file.read_block()?) as usize;
+                let length_u64 = u64::from_le_bytes(file.read_block()?);
+                let length = length_u64 as usize;
                 let mut payload = Vec::<u8>::new();
                 if length > SANE_MEM_LIMIT_BYTES
                     || payload.try_reserve_exact(length as usize).is_err()
@@ -186,7 +187,7 @@ impl RawJournalAdapter for SimpleDBJournal {
                 }
                 file.tracked_read(&mut payload)?;
                 let mut this_checksum = SCrc64::new();
-                this_checksum.update(&length.to_le_bytes());
+                this_checksum.update(&length_u64.to_le_bytes());
                 this_checksum.update(&payload);
                 match String::from_utf8(payload) {
                     Ok(k) if this_checksum.finish() == checksum => gs.data.borrow_mut().push(k),