Use utility methods to construct HashMaps and HashSets

In the next commit we'll bump the `hashbrown` version, which no
longer randomizes its hasher by default. Thus, we'll need to call
a different constructor in no-std builds from std builds.

Here we do a quick prefactor to use wrappers for constructors
instead of calling the tables directly to make the version bump
changeset smaller.

lightning/src/chain/chainmonitor.rs

@@ -419,7 +419,7 @@ where C::Target: chain::Filter,
 	/// transactions relevant to the watched channels.
 	pub fn new(chain_source: Option<C>, broadcaster: T, logger: L, feeest: F, persister: P) -> Self {
 		Self {
-			monitors: RwLock::new(HashMap::new()),
+			monitors: RwLock::new(new_hash_map()),
 			sync_persistence_id: AtomicCounter::new(),
 			chain_source,
 			broadcaster,

lightning/src/chain/channelmonitor.rs

@@ -1221,7 +1221,7 @@ impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
 			channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx
 		);
 
-		let mut outputs_to_watch = HashMap::new();
+		let mut outputs_to_watch = new_hash_map();
 		outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
 
 		Self::from_impl(ChannelMonitorImpl {
@@ -1247,17 +1247,17 @@ impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
 			on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
 
 			commitment_secrets: CounterpartyCommitmentSecrets::new(),
-			counterparty_claimable_outpoints: HashMap::new(),
-			counterparty_commitment_txn_on_chain: HashMap::new(),
-			counterparty_hash_commitment_number: HashMap::new(),
-			counterparty_fulfilled_htlcs: HashMap::new(),
+			counterparty_claimable_outpoints: new_hash_map(),
+			counterparty_commitment_txn_on_chain: new_hash_map(),
+			counterparty_hash_commitment_number: new_hash_map(),
+			counterparty_fulfilled_htlcs: new_hash_map(),
 
 			prev_holder_signed_commitment_tx: None,
 			current_holder_commitment_tx: holder_commitment_tx,
 			current_counterparty_commitment_number: 1 << 48,
 			current_holder_commitment_number,
 
-			payment_preimages: HashMap::new(),
+			payment_preimages: new_hash_map(),
 			pending_monitor_events: Vec::new(),
 			pending_events: Vec::new(),
 			is_processing_pending_events: false,
@@ -2154,7 +2154,7 @@ impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
 	/// HTLCs which were resolved on-chain (i.e. where the final HTLC resolution was done by an
 	/// event from this `ChannelMonitor`).
 	pub(crate) fn get_all_current_outbound_htlcs(&self) -> HashMap<HTLCSource, (HTLCOutputInCommitment, Option<PaymentPreimage>)> {
-		let mut res = HashMap::new();
+		let mut res = new_hash_map();
 		// Just examine the available counterparty commitment transactions. See docs on
 		// `fail_unbroadcast_htlcs`, below, for justification.
 		let us = self.inner.lock().unwrap();
@@ -2206,7 +2206,7 @@ impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
 			return self.get_all_current_outbound_htlcs();
 		}
 
-		let mut res = HashMap::new();
+		let mut res = new_hash_map();
 		macro_rules! walk_htlcs {
 			($holder_commitment: expr, $htlc_iter: expr) => {
 				for (htlc, source) in $htlc_iter {
@@ -3916,7 +3916,7 @@ impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitorImpl<Signer> {
 	/// Filters a block's `txdata` for transactions spending watched outputs or for any child
 	/// transactions thereof.
 	fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
-		let mut matched_txn = HashSet::new();
+		let mut matched_txn = new_hash_set();
 		txdata.iter().filter(|&&(_, tx)| {
 			let mut matches = self.spends_watched_output(tx);
 			for input in tx.input.iter() {
@@ -4431,7 +4431,7 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 		}
 
 		let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
-		let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
+		let mut counterparty_claimable_outpoints = hash_map_with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
 		for _ in 0..counterparty_claimable_outpoints_len {
 			let txid: Txid = Readable::read(reader)?;
 			let htlcs_count: u64 = Readable::read(reader)?;
@@ -4445,7 +4445,7 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 		}
 
 		let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
-		let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
+		let mut counterparty_commitment_txn_on_chain = hash_map_with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
 		for _ in 0..counterparty_commitment_txn_on_chain_len {
 			let txid: Txid = Readable::read(reader)?;
 			let commitment_number = <U48 as Readable>::read(reader)?.0;
@@ -4455,7 +4455,7 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 		}
 
 		let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
-		let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
+		let mut counterparty_hash_commitment_number = hash_map_with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
 		for _ in 0..counterparty_hash_commitment_number_len {
 			let payment_hash: PaymentHash = Readable::read(reader)?;
 			let commitment_number = <U48 as Readable>::read(reader)?.0;
@@ -4478,7 +4478,7 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 		let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
 
 		let payment_preimages_len: u64 = Readable::read(reader)?;
-		let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
+		let mut payment_preimages = hash_map_with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
 		for _ in 0..payment_preimages_len {
 			let preimage: PaymentPreimage = Readable::read(reader)?;
 			let hash = PaymentHash(Sha256::hash(&preimage.0[..]).to_byte_array());
@@ -4518,7 +4518,7 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 		}
 
 		let outputs_to_watch_len: u64 = Readable::read(reader)?;
-		let mut outputs_to_watch = HashMap::with_capacity(cmp::min(outputs_to_watch_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<Txid>() + mem::size_of::<u32>() + mem::size_of::<Vec<ScriptBuf>>())));
+		let mut outputs_to_watch = hash_map_with_capacity(cmp::min(outputs_to_watch_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<Txid>() + mem::size_of::<u32>() + mem::size_of::<Vec<ScriptBuf>>())));
 		for _ in 0..outputs_to_watch_len {
 			let txid = Readable::read(reader)?;
 			let outputs_len: u64 = Readable::read(reader)?;
@@ -4560,7 +4560,7 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 		let mut counterparty_node_id = None;
 		let mut confirmed_commitment_tx_counterparty_output = None;
 		let mut spendable_txids_confirmed = Some(Vec::new());
-		let mut counterparty_fulfilled_htlcs = Some(HashMap::new());
+		let mut counterparty_fulfilled_htlcs = Some(new_hash_map());
 		let mut initial_counterparty_commitment_info = None;
 		read_tlv_fields!(reader, {
 			(1, funding_spend_confirmed, option),

lightning/src/chain/onchaintx.rs

@@ -374,13 +374,13 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 		signer.provide_channel_parameters(&channel_parameters);
 
 		let pending_claim_requests_len: u64 = Readable::read(reader)?;
-		let mut pending_claim_requests = HashMap::with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
+		let mut pending_claim_requests = hash_map_with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
 		for _ in 0..pending_claim_requests_len {
 			pending_claim_requests.insert(Readable::read(reader)?, Readable::read(reader)?);
 		}
 
 		let claimable_outpoints_len: u64 = Readable::read(reader)?;
-		let mut claimable_outpoints = HashMap::with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
+		let mut claimable_outpoints = hash_map_with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
 		for _ in 0..claimable_outpoints_len {
 			let outpoint = Readable::read(reader)?;
 			let ancestor_claim_txid = Readable::read(reader)?;
@@ -445,8 +445,8 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner> OnchainTxHandler<ChannelSigner>
 			prev_holder_commitment: None,
 			signer,
 			channel_transaction_parameters: channel_parameters,
-			pending_claim_requests: HashMap::new(),
-			claimable_outpoints: HashMap::new(),
+			pending_claim_requests: new_hash_map(),
+			claimable_outpoints: new_hash_map(),
 			locktimed_packages: BTreeMap::new(),
 			onchain_events_awaiting_threshold_conf: Vec::new(),
 			pending_claim_events: Vec::new(),
@@ -834,7 +834,7 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner> OnchainTxHandler<ChannelSigner>
 		F::Target: FeeEstimator,
 	{
 		log_debug!(logger, "Updating claims view at height {} with {} matched transactions in block {}", cur_height, txn_matched.len(), conf_height);
-		let mut bump_candidates = HashMap::new();
+		let mut bump_candidates = new_hash_map();
 		for tx in txn_matched {
 			// Scan all input to verify is one of the outpoint spent is of interest for us
 			let mut claimed_outputs_material = Vec::new();
@@ -1020,7 +1020,7 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner> OnchainTxHandler<ChannelSigner>
 		where B::Target: BroadcasterInterface,
 			F::Target: FeeEstimator,
 	{
-		let mut bump_candidates = HashMap::new();
+		let mut bump_candidates = new_hash_map();
 		let onchain_events_awaiting_threshold_conf =
 			self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
 		for entry in onchain_events_awaiting_threshold_conf {

lightning/src/events/bump_transaction.rs

@@ -391,7 +391,7 @@ where
 	/// Returns a new instance backed by the given [`WalletSource`] that serves as an implementation
 	/// of [`CoinSelectionSource`].
 	pub fn new(source: W, logger: L) -> Self {
-		Self { source, logger, locked_utxos: Mutex::new(HashMap::new()) }
+		Self { source, logger, locked_utxos: Mutex::new(new_hash_map()) }
 	}
 
 	/// Performs coin selection on the set of UTXOs obtained from

lightning/src/lib.rs

@@ -167,10 +167,40 @@ mod prelude {
 	extern crate hashbrown;
 
 	pub use alloc::{vec, vec::Vec, string::String, collections::VecDeque, boxed::Box};
+
+	#[cfg(not(feature = "hashbrown"))]
+	mod std_hashtables {
+		pub(crate) use std::collections::{HashMap, HashSet, hash_map};
+
+		pub(crate) type OccupiedHashMapEntry<'a, K, V> =
+			std::collections::hash_map::OccupiedEntry<'a, K, V>;
+		pub(crate) type VacantHashMapEntry<'a, K, V> =
+			std::collections::hash_map::VacantEntry<'a, K, V>;
+	}
 	#[cfg(not(feature = "hashbrown"))]
-	pub use std::collections::{HashMap, HashSet, hash_map};
+	pub(crate) use std_hashtables::*;
+
+	#[cfg(feature = "hashbrown")]
+	mod hashbrown_tables {
+		pub(crate) use hashbrown::{HashMap, HashSet, hash_map};
+
+		pub(crate) type OccupiedHashMapEntry<'a, K, V> =
+			hashbrown::hash_map::OccupiedEntry<'a, K, V, hash_map::DefaultHashBuilder>;
+		pub(crate) type VacantHashMapEntry<'a, K, V> =
+			hashbrown::hash_map::VacantEntry<'a, K, V, hash_map::DefaultHashBuilder>;
+	}
 	#[cfg(feature = "hashbrown")]
-	pub use self::hashbrown::{HashMap, HashSet, hash_map};
+	pub(crate) use hashbrown_tables::*;
+
+	pub(crate) fn new_hash_map<K: core::hash::Hash + Eq, V>() -> HashMap<K, V> { HashMap::new() }
+	pub(crate) fn hash_map_with_capacity<K: core::hash::Hash + Eq, V>(cap: usize) -> HashMap<K, V> {
+		HashMap::with_capacity(cap)
+	}
+
+	pub(crate) fn new_hash_set<K: core::hash::Hash + Eq>() -> HashSet<K> { HashSet::new() }
+	pub(crate) fn hash_set_with_capacity<K: core::hash::Hash + Eq>(cap: usize) -> HashSet<K> {
+		HashSet::with_capacity(cap)
+	}
 
 	pub use alloc::borrow::ToOwned;
 	pub use alloc::string::ToString;

lightning/src/ln/channel.rs

@@ -6408,7 +6408,7 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
 				channel_ready_event_emitted: false,
 
 				#[cfg(any(test, fuzzing))]
-				historical_inbound_htlc_fulfills: HashSet::new(),
+				historical_inbound_htlc_fulfills: new_hash_set(),
 
 				channel_type,
 				channel_keys_id,
@@ -7209,7 +7209,7 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
 				channel_ready_event_emitted: false,
 
 				#[cfg(any(test, fuzzing))]
-				historical_inbound_htlc_fulfills: HashSet::new(),
+				historical_inbound_htlc_fulfills: new_hash_set(),
 
 				channel_type,
 				channel_keys_id,
@@ -8023,7 +8023,7 @@ impl<'a, 'b, 'c, ES: Deref, SP: Deref> ReadableArgs<(&'a ES, &'b SP, u32, &'c Ch
 		let channel_update_status = Readable::read(reader)?;
 
 		#[cfg(any(test, fuzzing))]
-		let mut historical_inbound_htlc_fulfills = HashSet::new();
+		let mut historical_inbound_htlc_fulfills = new_hash_set();
 		#[cfg(any(test, fuzzing))]
 		{
 			let htlc_fulfills_len: u64 = Readable::read(reader)?;