Make db and log config options more future-proof

Rename the "sql" directive to "db". Rename the "log" directive to
"log fs".

In the future, we'll maybe support more databases and more message
stores. Make it so it's easy to integrate these new festures to the
config file format.

config.in

@@ -1,2 +1,2 @@
-sql sqlite3 /var/lib/soju/main.db
+db sqlite3 /var/lib/soju/main.db
-log /var/lib/soju/logs/
+log fs /var/lib/soju/logs/

config/config.go

@@ -86,14 +86,18 @@ func parse(cfg scfg.Block) (*Server, error) {
 				return nil, err
 			}
 			srv.TLS = tls
-		case "sql":
+		case "db":
 			if err := d.ParseParams(&srv.SQLDriver, &srv.SQLSource); err != nil {
 				return nil, err
 			}
 		case "log":
-			if err := d.ParseParams(&srv.LogPath); err != nil {
+			var driver string
+			if err := d.ParseParams(&driver, &srv.LogPath); err != nil {
 				return nil, err
 			}
+			if driver != "fs" {
+				return nil, fmt.Errorf("directive %q: unknown driver %q", d.Name, driver)
+			}
 		case "http-origin":
 			srv.HTTPOrigins = d.Params
 		case "accept-proxy-ip":

doc/soju.1.scd

@@ -101,12 +101,10 @@ The following directives are supported:
 *tls* <cert> <key>
 	Enable TLS support. The certificate and the key files must be PEM-encoded.
 
-*sql* <driver> <source>
+*db* sqlite3 <path>
-	Set the SQL driver settings. The only supported driver is "sqlite3". The
+	Set the SQLite database path (default: "soju.db" in the current directory).
-	source is the path to the SQLite database file. By default, the path to the
-	database file is "soju.db".
 
-*log* <path>
+*log* fs <path>
 	Path to the bouncer logs root directory, or empty to disable logging. By
 	default, logging is disabled.