net.listen: make it more flexible

As noted in #94, it feels natural to call it like:
``net.listen({net.lo, '192.168.1.1'})``
Also, minor fixes were done in that function and corresponding docs.

diff --git a/daemon/README.rst b/daemon/README.rst
index 66dcfaa971cc561b1031a608c6081280a9724e2a..fe455858c16033536b29ce54a3aa0f44e0431eff 100644 (file)
--- a/daemon/README.rst
+++ b/daemon/README.rst
@@ -472,29 +472,23 @@ For when listening on ``localhost`` just doesn't cut it.
 
    Enable/disable using IPv4 for recursion.
 
-.. function:: net.listen(address, [port = 53, flags = {tls = false}])
+.. function:: net.listen(addressses, [port = 53, flags = {tls = (port == 853)}])
 
    :return: boolean
 
-   Listen on address, port and flags are optional.
+   Listen on addresses; port and flags are optional.
+   The addresses can be specified as a string or device,
+   or a list of addresses (recursively).
+   The command can be given multiple times, but note that it silently skips
+   any addresses that have already been bound.
 
-.. function:: net.listen({address1, ...}, [port = 53, flags = {tls = false}])
-
-   :return: boolean
-
-   Listen on list of addresses.
-
-.. function:: net.listen(interface, [port = 53, flags = {tls = false}])
-
-   :return: boolean
-
-   Listen on all addresses belonging to an interface.
-
-   Example:
+   Examples:
 
    .. code-block:: lua
 
-       net.listen(net.eth0) -- listen on eth0
+       net.listen('::1')
+       net.listen(net.lo, 5353)
+       net.listen({net.eth0, '127.0.0.1'}, 53853, {tls = true})
 
 .. function:: net.close(address, [port = 53])
 

diff --git a/daemon/bindings.c b/daemon/bindings.c
index ecc750c0d5821bae24043ce234b710a5a83456a2..e80b80b74f05d1819aa801e20b8c21f42a4cb12e 100644 (file)
--- a/daemon/bindings.c
+++ b/daemon/bindings.c
@@ -167,30 +167,43 @@ static int net_list(lua_State *L)
        return 1;
 }
 
-/** Listen on interface address list. */
-static int net_listen_iface(lua_State *L, int port, int flags)
+/** Listen on an address list represented by the top of lua stack. */
+static int net_listen_addrs(lua_State *L, int port, int flags)
 {
-       /* Expand 'addr' key if exists */
-       lua_getfield(L, 1, "addr");
-       if (lua_isnil(L, -1)) {
+       /* Case: table with 'addr' field; only follow that field directly. */
+       lua_getfield(L, -1, "addr");
+       if (!lua_isnil(L, -1)) {
+               lua_replace(L, -2);
+               kr_log_info("  .addr\n");
+       } else {
                lua_pop(L, 1);
-               lua_pushvalue(L, 1);
        }
 
-       /* Bind to address list */
-       struct engine *engine = engine_luaget(L);
-       size_t count = lua_rawlen(L, -1);
-       for (size_t i = 0; i < count; ++i) {
-               lua_rawgeti(L, -1, i + 1);
-               int ret = network_listen(&engine->net, lua_tostring(L, -1),
-                                        port, flags);
+       /* Case: string, representing a single address. */
+       const char *str = lua_tostring(L, -1);
+       if (str != NULL) {
+               kr_log_info("  string\n");
+               struct engine *engine = engine_luaget(L);
+               int ret = network_listen(&engine->net, str, port, flags);
                if (ret != 0) {
-                       kr_log_info("[system] bind to '%s#%d' %s\n", lua_tostring(L, -1), port, kr_strerror(ret));
+                       kr_log_info("[system] bind to '%s#%d' %s\n",
+                                       str, port, kr_strerror(ret));
                }
-               lua_pop(L, 1);
+               return ret == 0;
        }
 
-       lua_pushboolean(L, true);
+       /* Last case: table where all entries are added recursively. */
+       if (!lua_istable(L, -1)) {
+               format_error(L, "bad type for address");
+               lua_error(L);
+               return 0;
+       }
+       lua_pushnil(L);
+       while (lua_next(L, -2)) {
+               if (net_listen_addrs(L, port, flags) == 0)
+                       return 0;
+               lua_pop(L, 1);
+       }
        return 1;
 }
 
@@ -210,34 +223,28 @@ static int net_listen(lua_State *L)
 {
        /* Check parameters */
        int n = lua_gettop(L);
+       if (n < 1 || n > 3) {
+               format_error(L, "expected one to three arguments; usage:\n"
+                       "net.listen(addressses, [port = 53, flags = {tls = (port == 853)}])\n");
+               lua_error(L);
+       }
+
        int port = KR_DNS_PORT;
        if (n > 1 && lua_isnumber(L, 2)) {
                port = lua_tointeger(L, 2);
        }
+
        bool tls = (port == KR_DNS_TLS_PORT);
        if (n > 2 && lua_istable(L, 3)) {
                tls = table_get_flag(L, 3, "tls", tls);
        }
-
-       /* Process interface or (address, port, flags) triple. */
        int flags = tls ? (NET_TCP|NET_TLS) : (NET_TCP|NET_UDP);
-       if (lua_istable(L, 1)) {
-               return net_listen_iface(L, port, flags);
-       } else if (n < 1 || !lua_isstring(L, 1)) {
-               format_error(L, "expected 'listen(string addr, number port = 53[, bool tls = false])'");
-               lua_error(L);
-       }
-
-       /* Open resolution context cache */
-       struct engine *engine = engine_luaget(L);
-       int ret = network_listen(&engine->net, lua_tostring(L, 1), port, flags);
-       if (ret != 0) {
-               format_error(L, kr_strerror(ret));
-               lua_error(L);
-       }
-
-       lua_pushboolean(L, true);
-       return 1;
+       
+       /* Now focus on the first argument. */
+       lua_pop(L, n - 1);
+       int res = net_listen_addrs(L, port, flags);
+       lua_pushboolean(L, res);
+       return res;
 }
 
 /** Close endpoint. */