From 81291622eb9da914cfa1e6ba123245edfa48cd56 Mon Sep 17 00:00:00 2001
From: Gav Wood <gavin@ethcore.io>
Date: Sun, 13 Mar 2016 19:22:42 +0100
Subject: [PATCH] Avoid batches for now.

---
 parity/main.rs                     |  4 +--
 util/src/journaldb/archivedb.rs    |  8 +++--
 util/src/journaldb/refcounteddb.rs |  2 +-
 util/src/overlaydb.rs              | 50 +++++++++++++++++++++++++-----
 4 files changed, 52 insertions(+), 12 deletions(-)

diff --git a/parity/main.rs b/parity/main.rs
index 2bfa75e8a..002655951 100644
--- a/parity/main.rs
+++ b/parity/main.rs
@@ -427,9 +427,9 @@ impl Configuration {
 		}
 		client_config.pruning = match self.args.flag_pruning.as_str() {
 			"" | "archive" => journaldb::Algorithm::Archive,
-			"pruned" => journaldb::Algorithm::EarlyMerge,
+			"light" => journaldb::Algorithm::EarlyMerge,
 			"fast" => journaldb::Algorithm::OverlayRecent,
-			"slow" => journaldb::Algorithm::RefCounted,
+			"basic" => journaldb::Algorithm::RefCounted,
 			_ => { die!("Invalid pruning method given."); }
 		};
 		client_config.name = self.args.flag_identity.clone();
diff --git a/util/src/journaldb/archivedb.rs b/util/src/journaldb/archivedb.rs
index 19570b281..83a80b7c2 100644
--- a/util/src/journaldb/archivedb.rs
+++ b/util/src/journaldb/archivedb.rs
@@ -132,7 +132,7 @@ impl JournalDB for ArchiveDB {
 		Box::new(ArchiveDB {
 			overlay: MemoryDB::new(),
 			backing: self.backing.clone(),
-			latest_era: None,
+			latest_era: self.latest_era,
 		})
 	}
 
@@ -144,7 +144,7 @@ impl JournalDB for ArchiveDB {
 		self.latest_era.is_none()
 	}
 
-	fn commit(&mut self, _: u64, _: &H256, _: Option<(u64, H256)>) -> Result<u32, UtilError> {
+	fn commit(&mut self, now: u64, _: &H256, _: Option<(u64, H256)>) -> Result<u32, UtilError> {
 		let batch = DBTransaction::new();
 		let mut inserts = 0usize;
 		let mut deletes = 0usize;
@@ -160,6 +160,10 @@ impl JournalDB for ArchiveDB {
 				deletes += 1;
 			}
 		}
+		if self.latest_era.map_or(true, |e| now > e) {
+			try!(batch.put(&LATEST_ERA_KEY, &encode(&now)));
+			self.latest_era = Some(now);
+		}
 		try!(self.backing.write(batch));
 		Ok((inserts + deletes) as u32)
 	}
diff --git a/util/src/journaldb/refcounteddb.rs b/util/src/journaldb/refcounteddb.rs
index 09362676b..85f40e048 100644
--- a/util/src/journaldb/refcounteddb.rs
+++ b/util/src/journaldb/refcounteddb.rs
@@ -176,7 +176,7 @@ impl JournalDB for RefCountedDB {
 			}
 		}
 
-		let r = try!(self.forward.commit_to_batch(&batch));
+		let r = try!(self.forward.commit());
 		try!(self.backing.write(batch));
 		Ok(r)
 	}
diff --git a/util/src/overlaydb.rs b/util/src/overlaydb.rs
index 8166dd318..d176d38f6 100644
--- a/util/src/overlaydb.rs
+++ b/util/src/overlaydb.rs
@@ -72,13 +72,13 @@ impl OverlayDB {
 						if total_rc < 0 {
 							return Err(From::from(BaseDataError::NegativelyReferencedHash));
 						}
-						deletes += if self.put_payload(batch, &key, (back_value, total_rc as u32)) {1} else {0};
+						deletes += if self.put_payload_in_batch(batch, &key, (back_value, total_rc as u32)) {1} else {0};
 					}
 					None => {
 						if rc < 0 {
 							return Err(From::from(BaseDataError::NegativelyReferencedHash));
 						}
-						self.put_payload(batch, &key, (value, rc as u32));
+						self.put_payload_in_batch(batch, &key, (value, rc as u32));
 					}
 				};
 				ret += 1;
@@ -116,10 +116,32 @@ impl OverlayDB {
 	/// }
 	/// ```
 	pub fn commit(&mut self) -> Result<u32, UtilError> {
-		let batch = DBTransaction::new();
-		let r = try!(self.commit_to_batch(&batch));
-		try!(self.backing.write(batch));
-		Ok(r)
+		let mut ret = 0u32;
+		let mut deletes = 0usize;
+		for i in self.overlay.drain().into_iter() {
+			let (key, (value, rc)) = i;
+			if rc != 0 {
+				match self.payload(&key) {
+					Some(x) => {
+						let (back_value, back_rc) = x;
+						let total_rc: i32 = back_rc as i32 + rc;
+						if total_rc < 0 {
+							return Err(From::from(BaseDataError::NegativelyReferencedHash));
+						}
+						deletes += if self.put_payload(&key, (back_value, total_rc as u32)) {1} else {0};
+					}
+					None => {
+						if rc < 0 {
+							return Err(From::from(BaseDataError::NegativelyReferencedHash));
+						}
+						self.put_payload(&key, (value, rc as u32));
+					}
+				};
+				ret += 1;
+			}
+		}
+		trace!("OverlayDB::commit() deleted {} nodes", deletes);
+		Ok(ret)
 	}
 
 	/// Revert all operations on this object (i.e. `insert()`s and `kill()`s) since the
@@ -156,7 +178,7 @@ impl OverlayDB {
 	}
 
 	/// Put the refs and value of the given key, possibly deleting it from the db.
-	fn put_payload(&self, batch: &DBTransaction, key: &H256, payload: (Bytes, u32)) -> bool {
+	fn put_payload_in_batch(&self, batch: &DBTransaction, key: &H256, payload: (Bytes, u32)) -> bool {
 		if payload.1 > 0 {
 			let mut s = RlpStream::new_list(2);
 			s.append(&payload.1);
@@ -168,6 +190,20 @@ impl OverlayDB {
 			true
 		}
 	}
+
+	/// Put the refs and value of the given key, possibly deleting it from the db.
+	fn put_payload(&self, key: &H256, payload: (Bytes, u32)) -> bool {
+		if payload.1 > 0 {
+			let mut s = RlpStream::new_list(2);
+			s.append(&payload.1);
+			s.append(&payload.0);
+			self.backing.put(&key.bytes(), s.as_raw()).expect("Low-level database error. Some issue with your hard disk?");
+			false
+		} else {
+			self.backing.delete(&key.bytes()).expect("Low-level database error. Some issue with your hard disk?");
+			true
+		}
+	}
 }
 
 impl HashDB for OverlayDB {