db: add --ignore-dbversion to override database checks.

At your own risk, of course.

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

daemon/db.c

@@ -1172,9 +1172,17 @@ static void db_check_version(struct lightningd_state *dstate)
 			fatal("db_check_version:step gave %s:%s",
 			      sqlite3_errstr(err), sqlite3_errmsg(sql));
 		ver = sqlite3_column_str(stmt, 0);
-		if (!streq(ver, VERSION))
-			fatal("DATABASE NEEDS UPDATE. Version %s does not match %s",
-			      ver, VERSION);
+		if (!streq(ver, VERSION)) {
+			if (dstate->config.db_version_ignore)
+				log_unusual(dstate->base_log,
+					    "DATABASE NEEDS UPDATE."
+					    " Version %s does not match %s",
+					    ver, VERSION);
+			else
+				fatal("DATABASE NEEDS UPDATE."
+				      " Version %s does not match %s",
+				      ver, VERSION);
+		}
 	}
 	tal_free(ctx);
 }

daemon/lightningd.c

@@ -161,6 +161,10 @@ static void config_register_opts(struct lightningd_state *dstate)
 	opt_register_noarg("--disable-irc", opt_set_invbool,
 			   &dstate->config.use_irc,
 			   "Disable IRC peer discovery for routing");
+
+	opt_register_noarg("--ignore-dbversion", opt_set_bool,
+			   &dstate->config.db_version_ignore,
+			   "Continue despite invalid database version (DANGEROUS!)");
 }
 
 static void dev_register_opts(struct lightningd_state *dstate)
@@ -228,6 +232,9 @@ static const struct config testnet_config = {
 
 	/* Discover new peers using IRC */
 	.use_irc = true,
+
+	/* Don't ignore database version */
+	.db_version_ignore = false,
 };
 
 /* aka. "Dude, where's my coins?" */
@@ -289,6 +296,9 @@ static const struct config mainnet_config = {
 
 	/* Discover new peers using IRC */
 	.use_irc = true,
+
+	/* Don't ignore database version */
+	.db_version_ignore = false,
 };
 
 static void check_config(struct lightningd_state *dstate)

daemon/lightningd.h

@@ -62,6 +62,9 @@ struct config {
 
 	/* Whether to enable IRC peer discovery. */
 	bool use_irc;
+
+	/* Whether to ignore database version. */
+	bool db_version_ignore;
 };
 
 /* Here's where the global variables hide! */