add udebug support

Signed-off-by: Felix Fietkau <nbd@nbd.name>

CMakeLists.txt

@@ -9,14 +9,16 @@ SET(SOURCES dns.c announce.c cache.c service.c util.c ubus.c interface.c)
 
 FIND_PATH(ubox_include_dir NAMES libubox/usock.h)
 FIND_PATH(ubus_include_dir NAMES libubus.h)
-INCLUDE_DIRECTORIES(${ubox_include_dir} ${ubus_include_dir})
+FIND_PATH(udebug_include_dir NAMES udebug.h)
+INCLUDE_DIRECTORIES(${ubox_include_dir} ${ubus_include_dir} ${udebug_include_dir})
 
 FIND_LIBRARY(ubox NAMES ubox)
 FIND_LIBRARY(ubus NAMES ubus)
 FIND_LIBRARY(blobmsg_json NAMES blobmsg_json)
 FIND_LIBRARY(json NAMES json json-c)
+FIND_LIBRARY(udebug NAMES udebug)
 
-SET(LIBS ${ubox} ${ubus} ${blobmsg_json} ${json} resolv)
+SET(LIBS ${ubox} ${ubus} ${blobmsg_json} ${json} resolv ${udebug})
 
 IF(DEBUG)
   ADD_DEFINITIONS(-DDEBUG -g3)

main.c

@@ -26,6 +26,7 @@
 #include <netinet/in.h>
 #include <arpa/nameser.h>
 
+#include <udebug.h>
 #include <libubus.h>
 #include <libubox/uloop.h>
 
@@ -40,6 +41,53 @@
 int cfg_proto = 0;
 int cfg_no_subnet = 0;
 
+static struct udebug ud;
+static struct udebug_buf udb;
+static bool udebug_enabled;
+
+static void
+umdns_udebug_vprintf(const char *format, va_list ap)
+{
+	if (!udebug_enabled)
+		return;
+
+	udebug_entry_init(&udb);
+	udebug_entry_vprintf(&udb, format, ap);
+	udebug_entry_add(&udb);
+}
+
+void umdns_udebug_printf(const char *format, ...)
+{
+	va_list ap;
+
+	va_start(ap, format);
+	umdns_udebug_vprintf(format, ap);
+	va_end(ap);
+}
+
+void umdns_udebug_set_enabled(bool val)
+{
+	static const struct udebug_buf_meta meta = {
+		.name = "umdns_log",
+		.format = UDEBUG_FORMAT_STRING,
+	};
+
+	if (udebug_enabled == val)
+		return;
+
+	udebug_enabled = val;
+	if (!val) {
+		udebug_buf_free(&udb);
+		udebug_free(&ud);
+		return;
+	}
+
+	udebug_init(&ud);
+	udebug_auto_connect(&ud, NULL);
+	udebug_buf_init(&udb, 1024, 64 * 1024);
+	udebug_buf_add(&ud, &udb, &meta);
+}
+
 static void
 signal_shutdown(int signal)
 {

ubus.c

@@ -28,6 +28,7 @@
 
 static struct ubus_auto_conn conn;
 static struct blob_buf b;
+static struct ubus_subscriber udebug_sub;
 
 static int
 umdns_reload(struct ubus_context *ctx, struct ubus_object *obj,
@@ -283,14 +284,87 @@ static struct ubus_object umdns_object = {
 	.n_methods = ARRAY_SIZE(umdns_methods),
 };
 
+static struct blob_attr *
+find_attr(struct blob_attr *attr, const char *name, enum blobmsg_type type)
+{
+	struct blobmsg_policy policy = { name, type };
+	struct blob_attr *ret;
+
+	if (!attr)
+		return NULL;
+
+	blobmsg_parse_attr(&policy, 1, &ret, attr);
+
+	return ret;
+}
+
+static void
+umdns_udebug_config_cb(struct blob_attr *data)
+{
+	enum {
+		CFG_ATTR_ENABLED,
+		__CFG_ATTR_MAX
+	};
+	static const struct blobmsg_policy policy[__CFG_ATTR_MAX] = {
+		[CFG_ATTR_ENABLED] = { "enabled", BLOBMSG_TYPE_STRING },
+	};
+	struct blob_attr *tb[__CFG_ATTR_MAX];
+	bool en;
+
+	data = find_attr(data, "service", BLOBMSG_TYPE_TABLE);
+	data = find_attr(data, "umdns", BLOBMSG_TYPE_TABLE);
+	if (!data)
+		return;
+
+	blobmsg_parse_attr(policy, __CFG_ATTR_MAX, tb, data);
+	if (!tb[CFG_ATTR_ENABLED])
+		return;
+
+	en = !!atoi(blobmsg_get_string(tb[CFG_ATTR_ENABLED]));
+	umdns_udebug_set_enabled(en);
+}
+
+static int
+umdns_udebug_notify_cb(struct ubus_context *ctx, struct ubus_object *obj,
+			struct ubus_request_data *req, const char *method,
+			struct blob_attr *msg)
+{
+	umdns_udebug_config_cb(msg);
+
+	return 0;
+}
+
+static void
+umdns_udebug_req_cb(struct ubus_request *req, int type, struct blob_attr *msg)
+{
+	umdns_udebug_config_cb(msg);
+}
+
+static bool
+umdns_udebug_sub_cb(struct ubus_context *ctx, struct ubus_subscriber *sub,
+		     const char *path)
+{
+	return !strcmp(path, "udebug");
+}
+
+
 static void
 ubus_connect_handler(struct ubus_context *ctx)
 {
+	uint32_t id;
 	int ret;
 
 	ret = ubus_add_object(ctx, &umdns_object);
 	if (ret)
 		fprintf(stderr, "Failed to add object: %s\n", ubus_strerror(ret));
+
+	udebug_sub.cb = umdns_udebug_notify_cb;
+	udebug_sub.new_obj_cb = umdns_udebug_sub_cb;
+	ubus_register_subscriber(&conn.ctx, &udebug_sub);
+	if (ubus_lookup_id(&conn.ctx, "udebug", &id) == 0) {
+		ubus_subscribe(&conn.ctx, &udebug_sub, id);
+		ubus_invoke(&conn.ctx, id, "get_config", NULL, umdns_udebug_req_cb, NULL, 1000);
+	}
 }
 
 void

util.h

@@ -18,6 +18,7 @@
 #include <time.h>
 
 #define DBG(level, fmt, ...) do { \
+	umdns_udebug_printf("[%d] [%s:%d] " fmt, level, __func__, __LINE__, ## __VA_ARGS__); \
 	if (debug >= level) \
 		fprintf(stderr, "mdnsd: %s (%d): " fmt, __func__, __LINE__, ## __VA_ARGS__); \
 	} while (0)
@@ -41,4 +42,7 @@ extern void get_hostname(void);
 extern uint32_t rand_time_delta(uint32_t t);
 extern time_t monotonic_time(void);
 
+void umdns_udebug_set_enabled(bool val);
+void umdns_udebug_printf(const char *format, ...);
+
 #endif