simplify backup lib structure (pub use xxx:*), improve doc

src/backup/chunk_store.rs

@@ -30,6 +30,7 @@ impl Default for GarbageCollectionStatus {
     }
 }
 
+/// File system based chunk store
 pub struct ChunkStore {
     name: String, // used for error reporting
     pub (crate) base: PathBuf,

src/backup/chunker.rs

@@ -1,15 +1,16 @@
-//! Slinding window chunker (Buzhash)
-//!
-//! This is a rewrite of *casync* chunker (cachunker.h) in rust.
-//!
-//! Hashing by cyclic polynomial (also called Buzhash) has the benefit
-//! of avoiding multiplications, using barrel shifts instead. For more
-//! information please take a look at the [Rolling
-//! Hash](https://en.wikipedia.org/wiki/Rolling_hash) artikel from
-//! wikipedia.
 
 const CA_CHUNKER_WINDOW_SIZE: usize = 48;
 
+/// Slinding window chunker (Buzhash)
+///
+/// This is a rewrite of *casync* chunker (cachunker.h) in rust.
+///
+/// Hashing by cyclic polynomial (also called Buzhash) has the benefit
+/// of avoiding multiplications, using barrel shifts instead. For more
+/// information please take a look at the [Rolling
+/// Hash](https://en.wikipedia.org/wiki/Rolling_hash) artikel from
+/// wikipedia.
+
 pub struct Chunker {
     h: u32,
     window_size: usize,

src/backup/datastore.rs

@@ -15,15 +15,23 @@ use super::dynamic_index::*;
 
 use chrono::{Utc, TimeZone};
 
+/// Datastore Management
+///
+/// A Datastore can store severals backups, and provides the
+/// management interface for backup.
 pub struct DataStore {
     chunk_store: Arc<ChunkStore>,
     gc_mutex: Mutex<bool>,
 }
 
+/// Detailed Backup Information
 #[derive(Debug)]
 pub struct BackupInfo {
+    /// Type of backup
     pub backup_type: String,
+    /// Unique (for this type) ID
     pub backup_id: String,
+    /// Backup timestamp
     pub backup_time: DateTime<Utc>,
 }
 

src/backup/dynamic_index.rs

@@ -12,9 +12,10 @@ use std::os::unix::io::AsRawFd;
 use uuid::Uuid;
 //use chrono::{Local, TimeZone};
 
+/// Header format definition for dynamic index files (`.dixd`)
 #[repr(C)]
-//pub struct DynamicIndexHeader {
 pub struct DynamicIndexHeader {
+    /// The string `PROXMOX-DIDX`
     pub magic: [u8; 12],
     pub version: u32,
     pub uuid: [u8; 16],

src/backup/fixed_index.rs

@@ -10,8 +10,10 @@ use std::os::unix::io::AsRawFd;
 use uuid::Uuid;
 use chrono::{Local, TimeZone};
 
+/// Header format definition for fixed index files (`.fixd`)
 #[repr(C)]
 pub struct FixedIndexHeader {
+    /// The string `PROXMOX-FIDX`
     pub magic: [u8; 12],
     pub version: u32,
     pub uuid: [u8; 16],