add some compaction related interfaces

Signed-off-by: Jason Volk <jason@zemos.net>

src/database/map/compact.rs

@@ -0,0 +1,62 @@
+use conduwuit::{implement, Err, Result};
+use rocksdb::{BottommostLevelCompaction, CompactOptions};
+
+use crate::keyval::KeyBuf;
+
+#[derive(Clone, Debug, Default)]
+pub struct Options {
+	/// Key range to start and stop compaction.
+	pub range: (Option<KeyBuf>, Option<KeyBuf>),
+
+	/// (None, None) - all levels to all necessary levels
+	/// (None, Some(1)) - compact all levels into level 1
+	/// (Some(1), None) - compact level 1 into level 1
+	/// (Some(_), Some(_) - currently unsupported
+	pub level: (Option<usize>, Option<usize>),
+
+	/// run compaction until complete. if false only one pass is made, and the
+	/// results of that pass are not further recompacted.
+	pub exhaustive: bool,
+
+	/// waits for other compactions to complete, then runs this compaction
+	/// exclusively before allowing automatic compactions to resume.
+	pub exclusive: bool,
+}
+
+#[implement(super::Map)]
+#[tracing::instrument(
+	name = "compact",
+	level = "info"
+	skip(self),
+	fields(%self),
+)]
+pub fn compact_blocking(&self, opts: Options) -> Result {
+	let mut co = CompactOptions::default();
+	co.set_exclusive_manual_compaction(opts.exclusive);
+	co.set_bottommost_level_compaction(match opts.exhaustive {
+		| true => BottommostLevelCompaction::Force,
+		| false => BottommostLevelCompaction::ForceOptimized,
+	});
+
+	match opts.level {
+		| (None, None) => {
+			co.set_change_level(true);
+			co.set_target_level(-1);
+		},
+		| (None, Some(level)) => {
+			co.set_change_level(true);
+			co.set_target_level(level.try_into()?);
+		},
+		| (Some(level), None) => {
+			co.set_change_level(false);
+			co.set_target_level(level.try_into()?);
+		},
+		| (Some(_), Some(_)) => return Err!("compacting between specific levels not supported"),
+	};
+
+	self.db
+		.db
+		.compact_range_cf_opt(&self.cf(), opts.range.0, opts.range.1, &co);
+
+	Ok(())
+}