libplugin: support multi options.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Added: libplugin: support for options which accumulate if specified more than once ("multi": true).

Author: rustyrussell

plugins/libplugin.c

@@ -62,6 +62,8 @@ struct plugin_option {
 	const char *depr_start, *depr_end;
 	/* If true, allow setting after plugin has initialized */
 	bool dynamic;
+	/* If true, allow multiple settings. */
+	bool multi;
 };
 
 struct plugin {
@@ -1262,6 +1264,7 @@ handle_getmanifest(struct command *getmanifest_cmd,
 		json_add_string(params, "description", p->opts[i].description);
 		json_add_deprecated(params, "deprecated", p->opts[i].depr_start, p->opts[i].depr_end);
 		json_add_bool(params, "dynamic", p->opts[i].dynamic);
+		json_add_bool(params, "multi", p->opts[i].multi);
 		if (p->opts[i].jsonfmt)
 			p->opts[i].jsonfmt(p, params, "default", p->opts[i].arg);
 		json_object_end(params);
@@ -1598,9 +1601,19 @@ static struct command_result *handle_init(struct command *cmd,
 		if (!popt)
 			plugin_err(p, "lightningd specified unknown option '%s'?", name);
 
-		problem = popt->handle(p, json_strdup(tmpctx, buf, t+1), false, popt->arg);
-		if (problem)
-			plugin_err(p, "option '%s': %s", popt->name, problem);
+		if (popt->multi) {
+			size_t j;
+			const jsmntok_t *opt;
+			json_for_each_arr(j, opt, t+1) {
+				problem = popt->handle(p, json_strdup(tmpctx, buf, opt), false, popt->arg);
+				if (problem)
+					plugin_err(p, "option '%s': %s", popt->name, problem);
+			}
+		} else {
+			problem = popt->handle(p, json_strdup(tmpctx, buf, t+1), false, popt->arg);
+			if (problem)
+				plugin_err(p, "option '%s': %s", popt->name, problem);
+		}
 	}
 
 	if (p->init) {
@@ -2449,6 +2462,7 @@ static struct plugin *new_plugin(const tal_t *ctx,
 		o.depr_start = va_arg(ap, const char *);
 		o.depr_end = va_arg(ap, const char *);
 		o.dynamic = va_arg(ap, int); /* bool gets promoted! */
+		o.multi = va_arg(ap, int); /* bool gets promoted! */
 		tal_arr_expand(&p->opts, o);
 	}
 

plugins/libplugin.h

@@ -577,7 +577,7 @@ void *plugin_get_data_(struct plugin *plugin);
 #define plugin_get_data(plugin, type) ((type *)(plugin_get_data_(plugin)))
 
 /* Macro to define arguments */
-#define plugin_option_(name, type, description, set, jsonfmt, arg, dev_only, depr_start, depr_end, dynamic) \
+#define plugin_option_(name, type, description, set, jsonfmt, arg, dev_only, depr_start, depr_end, dynamic, multi) \
 	(name),								\
 	(type),								\
 	(description),							\
@@ -594,23 +594,27 @@ void *plugin_get_data_(struct plugin *plugin);
 	(dev_only),							\
 	(depr_start),							\
 	(depr_end),							\
-	(dynamic)
+	(dynamic),							\
+	(multi)
 
 /* jsonfmt can be NULL, but then default won't be printed */
 #define plugin_option(name, type, description, set, jsonfmt, arg)	\
-	plugin_option_((name), (type), (description), (set), (jsonfmt), (arg), false, NULL, NULL, false)
+	plugin_option_((name), (type), (description), (set), (jsonfmt), (arg), false, NULL, NULL, false, false)
 
 #define plugin_option_dev(name, type, description, set, jsonfmt, arg)	\
-	plugin_option_((name), (type), (description), (set), (jsonfmt), (arg), true, NULL, NULL, false)
+	plugin_option_((name), (type), (description), (set), (jsonfmt), (arg), true, NULL, NULL, false, false)
 
 #define plugin_option_dev_dynamic(name, type, description, set, jsonfmt, arg) \
-	plugin_option_((name), (type), (description), (set), (jsonfmt), (arg), true, NULL, NULL, true)
+	plugin_option_((name), (type), (description), (set), (jsonfmt), (arg), true, NULL, NULL, true, false)
 
 #define plugin_option_dynamic(name, type, description, set, jsonfmt, arg) \
-	plugin_option_((name), (type), (description), (set), (jsonfmt), (arg), false, NULL, NULL, true)
+	plugin_option_((name), (type), (description), (set), (jsonfmt), (arg), false, NULL, NULL, true, false)
 
 #define plugin_option_deprecated(name, type, description, depr_start, depr_end, set, jsonfmt, arg) \
-	plugin_option_((name), (type), (description), (set), (jsonfmt), (arg), false, (depr_start), (depr_end), false)
+	plugin_option_((name), (type), (description), (set), (jsonfmt), (arg), false, (depr_start), (depr_end), false, false)
+
+#define plugin_option_multi(name, type, description, set, jsonfmt, arg)	\
+	plugin_option_((name), (type), (description), (set), (jsonfmt), (arg), false, NULL, NULL, false, true)
 
 /* Standard helpers */
 char *u64_option(struct plugin *plugin, const char *arg, bool check_only, u64 *i);

plugins/xpay/Makefile

@@ -10,6 +10,6 @@ ALL_C_SOURCES += $(PLUGIN_XPAY_SRC)
 ALL_C_HEADERS += $(PLUGIN_XPAY_HDRS)
 
 # Make all plugins depend on all plugin headers, for simplicity.
-$(PLUGIN_XPAY_OBJS): $(PLUGIN_XPAY_HDRS)
+$(PLUGIN_XPAY_OBJS): $(PLUGIN_XPAY_HDRS) $(PLUGIN_LIB_HEADER)
 
 plugins/cln-xpay: $(PLUGIN_XPAY_OBJS) $(PLUGIN_LIB_OBJS) $(PLUGIN_COMMON_OBJS) $(JSMN_OBJS) $(CCAN_OBJS) bitcoin/chainparams.o common/gossmap.o common/gossmods_listpeerchannels.o common/fp16.o common/dijkstra.o common/bolt12.o common/bolt12_merkle.o common/sciddir_or_pubkey.o wire/bolt12_wiregen.o wire/onion_wiregen.o common/onionreply.o common/onion_encode.o common/sphinx.o common/hmac.o

tests/plugins/test_libplugin.c

@@ -12,6 +12,7 @@ struct test_libplugin {
 	bool self_disable;
 	bool dont_shutdown;
 	u32 dynamic_opt;
+	const char **strarr;
 };
 
 static struct test_libplugin *get_test_libplugin(struct plugin *plugin)
@@ -221,6 +222,13 @@ static const char *init(struct command *init_cmd,
 		plugin_log(p, LOG_DBG, "somearg = %s", tlp->somearg);
 	tlp->somearg = tal_free(tlp->somearg);
 
+	for (size_t i = 0; i < tal_count(tlp->strarr); i++) {
+		plugin_log(p, LOG_DBG, "multiopt#%zu = %s",
+			   i, tlp->strarr[i]);
+	}
+	if (tlp->somearg)
+		plugin_log(p, LOG_DBG, "somearg = %s", tlp->somearg);
+
 	if (tlp->self_disable)
 		return "Disabled via selfdisable option";
 
@@ -287,6 +295,25 @@ static const struct plugin_notification notifs[] = { {
 	}
 };
 
+static char *set_multi_string_option(struct plugin *plugin,
+				     const char *arg,
+				     bool check_only,
+				     const char ***arr)
+{
+	if (!check_only)
+		tal_arr_expand(arr, tal_strdup(*arr, arg));
+	return NULL;
+}
+
+static bool multi_string_jsonfmt(struct plugin *plugin, struct json_stream *js, const char *fieldname, const char ***arr)
+{
+	json_array_start(js, fieldname);
+	for (size_t i = 0; i < tal_count(*arr); i++)
+		json_add_string(js, NULL, (*arr)[i]);
+	json_array_end(js);
+	return true;
+}
+
 int main(int argc, char *argv[])
 {
 	setup_locale();
@@ -298,6 +325,7 @@ int main(int argc, char *argv[])
 	tlp->self_disable = false;
 	tlp->dont_shutdown = false;
 	tlp->dynamic_opt = 7;
+	tlp->strarr = tal_arr(tlp, const char *, 0);
 
 	plugin_main(argv, init, take(tlp), PLUGIN_RESTARTABLE, true, NULL,
 		    commands, ARRAY_SIZE(commands),
@@ -328,5 +356,11 @@ int main(int argc, char *argv[])
 					  "Set me!",
 					  set_dynamic, u32_jsonfmt,
 					  &tlp->dynamic_opt),
+		    plugin_option_multi("multiopt",
+					"string",
+					"Set me multiple times!",
+					set_multi_string_option,
+					multi_string_jsonfmt,
+					&tlp->strarr),
 		    NULL);
 }

tests/test_plugin.py

@@ -1682,6 +1682,7 @@ def test_libplugin(node_factory):
     assert l1.daemon.is_in_stderr(r"somearg-deprecated=test_opt: deprecated option")
 
     del l1.daemon.opts["somearg-deprecated"]
+    l1.daemon.opts["multiopt"] = ['hello', 'world']
     l1.start()
 
     # Test that check works as expected.
@@ -1695,6 +1696,9 @@ def test_libplugin(node_factory):
     # This works
     assert l1.rpc.check('checkthis', key=["test_libplugin", "name"]) == {'command_to_check': 'checkthis'}
 
+    assert l1.daemon.is_in_log('plugin-test_libplugin: multiopt#0 = hello')
+    assert l1.daemon.is_in_log('plugin-test_libplugin: multiopt#1 = world')
+
 
 def test_libplugin_deprecated(node_factory):
     """Sanity checks for plugins made with libplugin using deprecated args"""