wallet: add buildtime and runtime assertions on db enums.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

wallet/wallet.c

@@ -7,7 +7,6 @@
 #include <common/wireaddr.h>
 #include <inttypes.h>
 #include <lightningd/lightningd.h>
-#include <lightningd/log.h>
 #include <lightningd/peer_control.h>
 #include <lightningd/peer_htlcs.h>
 #include <onchaind/gen_onchain_wire.h>
@@ -83,7 +82,7 @@ bool wallet_add_utxo(struct wallet *w, struct utxo *utxo,
 	sqlite3_bind_blob(stmt, 1, &utxo->txid, sizeof(utxo->txid), SQLITE_TRANSIENT);
 	sqlite3_bind_int(stmt, 2, utxo->outnum);
 	sqlite3_bind_int64(stmt, 3, utxo->amount);
-	sqlite3_bind_int(stmt, 4, type);
+	sqlite3_bind_int(stmt, 4, wallet_output_type_in_db(type));
 	sqlite3_bind_int(stmt, 5, output_state_available);
 	sqlite3_bind_int(stmt, 6, utxo->keyindex);
 	if (utxo->close_info) {
@@ -161,14 +160,14 @@ bool wallet_update_output_status(struct wallet *w,
 	if (oldstatus != output_state_any) {
 		stmt = db_prepare(
 			w->db, "UPDATE outputs SET status=? WHERE status=? AND prev_out_tx=? AND prev_out_index=?");
-		sqlite3_bind_int(stmt, 1, newstatus);
-		sqlite3_bind_int(stmt, 2, oldstatus);
+		sqlite3_bind_int(stmt, 1, output_status_in_db(newstatus));
+		sqlite3_bind_int(stmt, 2, output_status_in_db(oldstatus));
 		sqlite3_bind_blob(stmt, 3, txid, sizeof(*txid), SQLITE_TRANSIENT);
 		sqlite3_bind_int(stmt, 4, outnum);
 	} else {
 		stmt = db_prepare(
 			w->db, "UPDATE outputs SET status=? WHERE prev_out_tx=? AND prev_out_index=?");
-		sqlite3_bind_int(stmt, 1, newstatus);
+		sqlite3_bind_int(stmt, 1, output_status_in_db(newstatus));
 		sqlite3_bind_blob(stmt, 2, txid, sizeof(*txid), SQLITE_TRANSIENT);
 		sqlite3_bind_int(stmt, 3, outnum);
 	}
@@ -176,18 +175,26 @@ bool wallet_update_output_status(struct wallet *w,
 	return sqlite3_changes(w->db->sql) > 0;
 }
 
+#define UTXO_FIELDS							\
+	"prev_out_tx, prev_out_index, value, type, status, keyindex, "	\
+	"channel_id, peer_id, commitment_point, confirmation_height, "	\
+	"spend_height"
 struct utxo **wallet_get_utxos(const tal_t *ctx, struct wallet *w, const enum output_status state)
 {
 	struct utxo **results;
 	int i;
+	sqlite3_stmt *stmt;
 
-	sqlite3_stmt *stmt = db_prepare(
-		w->db, "SELECT prev_out_tx, prev_out_index, value, type, status, keyindex, "
-		"channel_id, peer_id, commitment_point, confirmation_height, spend_height "
-		"FROM outputs WHERE status=?1 OR ?1=255");
-	sqlite3_bind_int(stmt, 1, state);
+	if (state == output_state_any)
+		stmt = db_prepare(w->db, "SELECT "UTXO_FIELDS
+				  " FROM outputs");
+	else {
+		stmt = db_prepare(w->db, "SELECT "UTXO_FIELDS
+				  " FROM outputs WHERE status=?1");
+		sqlite3_bind_int(stmt, 1, output_status_in_db(state));
+	}
 
-       	results = tal_arr(ctx, struct utxo*, 0);
+	results = tal_arr(ctx, struct utxo*, 0);
 	for (i=0; sqlite3_step(stmt) == SQLITE_ROW; i++) {
 		tal_resize(&results, i+1);
 		results[i] = tal(results, struct utxo);
@@ -1211,6 +1218,7 @@ void wallet_htlc_update(struct wallet *wallet, const u64 htlc_dbid,
 		wallet->db,
 		"UPDATE channel_htlcs SET hstate=?, payment_key=? WHERE id=?");
 
+	/* FIXME: htlc_state_in_db */
 	sqlite3_bind_int(stmt, 1, new_state);
 	sqlite3_bind_int64(stmt, 3, htlc_dbid);
 
@@ -1727,7 +1735,7 @@ void wallet_payment_set_status(struct wallet *wallet,
 			  "UPDATE payments SET status=? "
 			  "WHERE payment_hash=?");
 
-	sqlite3_bind_int(stmt, 1, newstatus);
+	sqlite3_bind_int(stmt, 1, wallet_payment_status_in_db(newstatus));
 	sqlite3_bind_sha256(stmt, 2, payment_hash);
 	db_exec_prepared(wallet->db, stmt);
 

wallet/wallet.h

@@ -5,6 +5,7 @@
 #include "db.h"
 #include <bitcoin/chainparams.h>
 #include <bitcoin/tx.h>
+#include <ccan/build_assert/build_assert.h>
 #include <ccan/crypto/shachain/shachain.h>
 #include <ccan/list/list.h>
 #include <ccan/tal/tal.h>
@@ -13,6 +14,7 @@
 #include <lightningd/chaintopology.h>
 #include <lightningd/htlc_end.h>
 #include <lightningd/invoice.h>
+#include <lightningd/log.h>
 #include <onchaind/onchain_wire.h>
 #include <wally_bip32.h>
 
@@ -46,6 +48,8 @@ struct wallet {
 /* Possible states for tracked outputs in the database. Not sure yet
  * whether we really want to have reservations reflected in the
  * database, it would simplify queries at the cost of some IO ops */
+/* /!\ This is a DB ENUM, please do not change the numbering of any
+ * already defined elements (adding is ok) /!\ */
 enum output_status {
 	output_state_available= 0,
 	output_state_reserved = 1,
@@ -55,10 +59,31 @@ enum output_status {
 	output_state_any = 255
 };
 
+static inline enum output_status output_status_in_db(enum output_status s)
+{
+	switch (s) {
+	case output_state_available:
+		BUILD_ASSERT(output_state_available == 0);
+		return s;
+	case output_state_reserved:
+		BUILD_ASSERT(output_state_reserved == 1);
+		return s;
+	case output_state_spent:
+		BUILD_ASSERT(output_state_spent == 2);
+		return s;
+	/* This one doesn't go into db */
+	case output_state_any:
+		break;
+	}
+	fatal("%s: %u is invalid", __func__, s);
+}
+
 /* Enumeration of all known output types. These include all types that
  * could ever end up on-chain and we may need to react upon. Notice
  * that `to_local`, `htlc_offer`, and `htlc_recv` may need immediate
  * action since they are encumbered with a CSV. */
+/* /!\ This is a DB ENUM, please do not change the numbering of any
+ * already defined elements (adding is ok) /!\ */
 enum wallet_output_type {
 	p2sh_wpkh = 0,
 	to_local = 1,
@@ -68,6 +93,31 @@ enum wallet_output_type {
 	p2wpkh = 6
 };
 
+static inline enum wallet_output_type wallet_output_type_in_db(enum wallet_output_type w)
+{
+	switch (w) {
+	case p2sh_wpkh:
+		BUILD_ASSERT(p2sh_wpkh == 0);
+		return w;
+	case to_local:
+		BUILD_ASSERT(to_local == 1);
+		return w;
+	case htlc_offer:
+		BUILD_ASSERT(htlc_offer == 3);
+		return w;
+	case htlc_recv:
+		BUILD_ASSERT(htlc_recv == 4);
+		return w;
+	case our_change:
+		BUILD_ASSERT(our_change == 5);
+		return w;
+	case p2wpkh:
+		BUILD_ASSERT(p2wpkh == 6);
+		return w;
+	}
+	fatal("%s: %u is invalid", __func__, w);
+}
+
 /* A database backed shachain struct. The datastructure is
  * writethrough, reads are performed from an in-memory version, all
  * writes are passed through to the DB. */
@@ -89,6 +139,22 @@ enum wallet_payment_status {
 	PAYMENT_FAILED = 2
 };
 
+static inline enum wallet_payment_status wallet_payment_status_in_db(enum wallet_payment_status w)
+{
+	switch (w) {
+	case PAYMENT_PENDING:
+		BUILD_ASSERT(PAYMENT_PENDING == 0);
+		return w;
+	case PAYMENT_COMPLETE:
+		BUILD_ASSERT(PAYMENT_COMPLETE == 1);
+		return w;
+	case PAYMENT_FAILED:
+		BUILD_ASSERT(PAYMENT_FAILED == 2);
+		return w;
+	}
+	fatal("%s: %u is invalid", __func__, w);
+}
+
 /* Outgoing payments. A simple persisted representation
  * of a payment we initiated. This can be used by
  * a UI (alongside invoices) to display the balance history.
@@ -424,6 +490,22 @@ enum invoice_status {
 	EXPIRED,
 };
 
+static inline enum invoice_status invoice_status_in_db(enum invoice_status s)
+{
+	switch (s) {
+	case UNPAID:
+		BUILD_ASSERT(UNPAID == 0);
+		return s;
+	case PAID:
+		BUILD_ASSERT(PAID == 1);
+		return s;
+	case EXPIRED:
+		BUILD_ASSERT(EXPIRED == 2);
+		return s;
+	}
+	fatal("%s: %u is invalid", __func__, s);
+}
+
 /* The information about an invoice */
 struct invoice_details {
 	/* Current invoice state */