Various minor store crate cleanups (#1991)

* Various minor store crate cleanups
* Fix optional IteratingReader counter
* Remove unused vec write functions, with changes to ser they required

Cargo.lock

@@ -910,7 +910,7 @@ dependencies = [
  "libc 0.2.43 (registry+https://github.com/rust-lang/crates.io-index)",
  "lmdb-zero 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "memmap 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memmap 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1327,7 +1327,7 @@ dependencies = [
 
 [[package]]
 name = "memmap"
-version = "0.6.2"
+version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "libc 0.2.43 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2951,7 +2951,7 @@ dependencies = [
 "checksum matches 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "7ffc5c5338469d4d3ea17d269fa8ea3512ad247247c30bd2df69e68309ed0a08"
 "checksum memchr 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "148fab2e51b4f1cfc66da2a7c32981d1d3c083a803978268bb11fe4b86925e7a"
 "checksum memchr 2.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0a3eb002f0535929f1199681417029ebea04aadc0c7a4224b46be99c7f5d6a16"
-"checksum memmap 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "e2ffa2c986de11a9df78620c01eeaaf27d94d3ff02bf81bfcca953102dd0c6ff"
+"checksum memmap 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "6585fd95e7bb50d6cc31e20d4cf9afb4e2ba16c5846fc76793f11218da9c475b"
 "checksum memoffset 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0f9dc261e2b62d7a622bf416ea3c5245cdd5d9a7fcc428c0d06804dfce1775b3"
 "checksum mime 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)" = "0a907b83e7b9e987032439a387e187119cddafc92d5c2aaeb1d92580a793f630"
 "checksum mime_guess 2.0.0-alpha.6 (registry+https://github.com/rust-lang/crates.io-index)" = "30de2e4613efcba1ec63d8133f344076952090c122992a903359be5a4f99c3ed"

store/Cargo.toml

@@ -17,7 +17,7 @@ libc = "0.2"
 failure = "0.1"
 failure_derive = "0.1"
 lmdb-zero = "0.4.4"
-memmap = "0.6.2"
+memmap = "0.7"
 serde = "1"
 serde_derive = "1"
 log = "0.4"

store/src/pmmr.rs

@@ -140,9 +140,7 @@ impl<T: PMMRable> Backend<T> for PMMRBackend<T> {
 
 		// Rewind the hash file accounting for pruned/compacted pos
 		let shift = self.prune_list.get_shift(position);
-		self.hash_file
+		self.hash_file.rewind(position - shift);
-			.rewind(position - shift)
-			.map_err(|e| format!("Failed to rewind hash file. {}", e))?;
 
 		// Rewind the data file accounting for pruned/compacted pos
 		let leaf_shift = self.prune_list.get_leaf_shift(position);
@@ -253,19 +251,16 @@ impl<T: PMMRable> PMMRBackend<T> {
 	/// Syncs all files to disk. A call to sync is required to ensure all the
 	/// data has been successfully written to disk.
 	pub fn sync(&mut self) -> io::Result<()> {
-		self.hash_file.flush()?;
+		self.hash_file
-
+			.flush()
-		if let Err(e) = self.data_file.flush() {
+			.and(self.data_file.flush())
-			return Err(io::Error::new(
+			.and(self.leaf_set.flush())
+			.map_err(|e| {
+				io::Error::new(
 					io::ErrorKind::Interrupted,
-				format!("Could not write to log data storage, disk full? {:?}", e),
+					format!("Could not write to state storage, disk full? {:?}", e),
-			));
+				)
-		}
+			})
-
-		// Flush the leaf_set to disk.
-		self.leaf_set.flush()?;
-
-		Ok(())
 	}
 
 	/// Discard the current, non synced state of the backend.
@@ -275,23 +270,15 @@ impl<T: PMMRable> PMMRBackend<T> {
 		self.data_file.discard();
 	}
 
-	/// Return the data file path
-	pub fn data_file_path(&self) -> String {
-		self.get_data_file_path()
-	}
-
 	/// Takes the leaf_set at a given cutoff_pos and generates an updated
-	/// prune_list. Saves the updated prune_list to disk
+	/// prune_list. Saves the updated prune_list to disk, compacts the hash
-	/// Compacts the hash and data files based on the prune_list and saves both
+	/// and data files based on the prune_list and saves both to disk.
-	/// to disk.
 	///
 	/// A cutoff position limits compaction on recent data.
-	/// This will be the last position of a particular block
+	/// This will be the last position of a particular block to keep things
-	/// to keep things aligned.
+	/// aligned. The block_marker in the db/index for the particular block
-	/// The block_marker in the db/index for the particular block
+	/// will have a suitable output_pos. This is used to enforce a horizon
-	/// will have a suitable output_pos.
+	/// after which the local node should have all the data to allow rewinding.
-	/// This is used to enforce a horizon after which the local node
-	/// should have all the data to allow rewinding.
 	pub fn check_compact<P>(
 		&mut self,
 		cutoff_pos: u64,

store/src/types.rs

@@ -14,10 +14,8 @@
 //! Common storage-related types
 use memmap;
 
-use std::cmp;
 use std::fs::{self, File, OpenOptions};
-use std::io::{self, BufRead, BufReader, BufWriter, ErrorKind, Read, Write};
+use std::io::{self, BufWriter, ErrorKind, Read, Write};
-use std::path::Path;
 
 use core::core::hash::Hash;
 use core::ser::{self, FixedLength};
@@ -67,9 +65,8 @@ impl HashFile {
 	}
 
 	/// Rewind the backend file to the specified position.
-	pub fn rewind(&mut self, position: u64) -> io::Result<()> {
+	pub fn rewind(&mut self, position: u64) {
-		self.file.rewind(position * Hash::LEN as u64);
+		self.file.rewind(position * Hash::LEN as u64)
-		Ok(())
 	}
 
 	/// Flush unsynced changes to the hash file to disk.
@@ -320,56 +317,3 @@ impl AppendOnlyFile {
 		self.path.clone()
 	}
 }
-
-/// Read an ordered vector of scalars from a file.
-pub fn read_ordered_vec<T>(path: &str, elmt_len: usize) -> io::Result<Vec<T>>
-where
-	T: ser::Readable + cmp::Ord,
-{
-	let file_path = Path::new(&path);
-	let mut ovec = Vec::with_capacity(1000);
-	if file_path.exists() {
-		let mut file = BufReader::with_capacity(elmt_len * 1000, File::open(&path)?);
-		loop {
-			// need a block to end mutable borrow before consume
-			let buf_len = {
-				let buf = file.fill_buf()?;
-				if buf.len() == 0 {
-					break;
-				}
-				let elmts_res: Result<Vec<T>, ser::Error> = ser::deserialize(&mut &buf[..]);
-				match elmts_res {
-					Ok(elmts) => for elmt in elmts {
-						if let Err(idx) = ovec.binary_search(&elmt) {
-							ovec.insert(idx, elmt);
-						}
-					},
-					Err(_) => {
-						return Err(io::Error::new(
-							io::ErrorKind::InvalidData,
-							format!("Corrupted storage, could not read file at {}", path),
-						));
-					}
-				}
-				buf.len()
-			};
-			file.consume(buf_len);
-		}
-	}
-	Ok(ovec)
-}
-
-/// Writes an ordered vector to a file
-pub fn write_vec<T>(path: &str, v: &Vec<T>) -> io::Result<()>
-where
-	T: ser::Writeable,
-{
-	let mut file_path = File::create(&path)?;
-	ser::serialize(&mut file_path, v).map_err(|_| {
-		io::Error::new(
-			io::ErrorKind::InvalidInput,
-			format!("Failed to serialize data when writing to {}", path),
-		)
-	})?;
-	Ok(())
-}