Removes parking lot dependency

There is some circumventions around the absence of upgradable read locks. Not sure if they are valid...

Cargo.toml

@@ -20,7 +20,6 @@ libc = "0.2"
 log = "0.4.8"
 lz4 = "1.24.0"
 memmap2 = "0.5"
-parking_lot = "0.12.0"
 rand = "0.8.4"
 snap = "1"
 

src/btree/iter.rs

@@ -11,7 +11,7 @@ use super::*;
 use crate::{
 	btree::BTreeTable, db::CommitOverlay, error::Result, log::LogQuery, table::key::TableKeyQuery,
 };
-use parking_lot::RwLock;
+use std::sync::RwLock;
 
 #[derive(Debug, PartialEq, Eq, Clone, Copy)]
 pub enum SeekTo<'a> {
@@ -75,7 +75,7 @@ impl<'a> BTreeIterator<'a> {
 		log: &'a RwLock<crate::log::LogOverlays>,
 		commit_overlay: &'a RwLock<Vec<CommitOverlay>>,
 	) -> Result<Self> {
-		let record_id = log.read().last_record_id(col);
+		let record_id = log.read().unwrap().last_record_id(col);
 		let tree = table.with_locked(|btree| BTree::open(btree, log, record_id))?;
 		let iter = BTreeIterState::new(tree.record_id);
 		Ok(BTreeIterator {
@@ -91,7 +91,7 @@ impl<'a> BTreeIterator<'a> {
 
 	pub fn seek(&mut self, key: &[u8]) -> Result<()> {
 		// seek require log do not change
-		let log = self.log.read();
+		let log = self.log.read().unwrap();
 		let record_id = log.last_record_id(self.col);
 		self.last_key = LastKey::Seeked(key.to_vec());
 		self.pending_backend = None;
@@ -103,7 +103,7 @@ impl<'a> BTreeIterator<'a> {
 	}
 
 	pub fn seek_to_last(&mut self) -> Result<()> {
-		let log = self.log.read();
+		let log = self.log.read().unwrap();
 		let record_id = log.last_record_id(self.col);
 		self.last_key = LastKey::End;
 		self.seek_backend_to_last(record_id, self.table, &*log)
@@ -123,13 +123,13 @@ impl<'a> BTreeIterator<'a> {
 
 		loop {
 			// Lock log over function call (no btree struct change).
-			let commit_overlay = self.commit_overlay.read();
+			let commit_overlay = self.commit_overlay.read().unwrap();
 			let next_commit_overlay =
 				commit_overlay.get(col as usize).and_then(|o| match direction {
 					IterDirection::Forward => o.btree_next(&self.last_key),
 					IterDirection::Backward => o.btree_prev(&self.last_key),
 				});
-			let log = self.log.read();
+			let log = self.log.read().unwrap();
 			let record_id = log.last_record_id(self.col);
 			// No consistency over iteration, allows dropping lock to overlay.
 			drop(commit_overlay);

src/btree/mod.rs

@@ -17,7 +17,7 @@ use crate::{
 };
 pub use iter::{BTreeIterator, LastIndex, LastKey};
 use node::SeparatorInner;
-use parking_lot::RwLock;
+use std::sync::RwLock;
 
 #[allow(clippy::module_inception)]
 mod btree;
@@ -172,13 +172,13 @@ impl BTreeTable {
 		address: Address,
 		log: &impl LogQuery,
 	) -> Result<Option<(u8, Value)>> {
-		let tables = self.tables.read();
+		let tables = self.tables.read().unwrap();
 		let btree = self.locked(&tables);
 		Column::get_value(key, address, btree, log)
 	}
 
 	pub fn flush(&self) -> Result<()> {
-		let tables = self.tables.read();
+		let tables = self.tables.read().unwrap();
 		for t in tables.iter() {
 			t.flush()?;
 		}
@@ -216,13 +216,13 @@ impl BTreeTable {
 	}
 
 	pub fn with_locked<R>(&self, mut apply: impl FnMut(TablesRef) -> Result<R>) -> Result<R> {
-		let locked_tables = &*self.tables.read();
+		let locked_tables = &*self.tables.read().unwrap();
 		let locked = self.locked(locked_tables);
 		apply(locked)
 	}
 
 	pub fn enact_plan(&self, action: LogAction, log: &mut LogReader) -> Result<()> {
-		let tables = self.tables.read();
+		let tables = self.tables.read().unwrap();
 		match action {
 			LogAction::InsertValue(record) => {
 				tables[record.table.size_tier() as usize].enact_plan(record.index, log)?;
@@ -233,7 +233,7 @@ impl BTreeTable {
 	}
 
 	pub fn validate_plan(&self, action: LogAction, log: &mut LogReader) -> Result<()> {
-		let tables = self.tables.upgradable_read();
+		let tables = self.tables.write().unwrap();
 		match action {
 			LogAction::InsertValue(record) => {
 				tables[record.table.size_tier() as usize].validate_plan(record.index, log)?;
@@ -247,15 +247,15 @@ impl BTreeTable {
 	}
 
 	pub fn complete_plan(&self, log: &mut LogWriter) -> Result<()> {
-		let tables = self.tables.read();
+		let tables = self.tables.read().unwrap();
 		for t in tables.iter() {
 			t.complete_plan(log)?;
 		}
 		Ok(())
 	}
 
 	pub fn refresh_metadata(&self) -> Result<()> {
-		let tables = self.tables.read();
+		let tables = self.tables.read().unwrap();
 		for t in tables.iter() {
 			t.refresh_metadata()?;
 		}
@@ -436,7 +436,7 @@ pub mod commit_overlay {
 		) -> Result<()> {
 			let record_id = writer.record_id();
 
-			let locked_tables = btree.tables.read();
+			let locked_tables = btree.tables.read().unwrap();
 			let locked = btree.locked(&locked_tables);
 			let mut tree = BTree::open(locked, writer, record_id)?;