From 9dcc37a77cb29282e27a7502ffe91a4613ce769e Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@nbd.name>
Date: Mon, 20 Nov 2023 17:00:08 +0100
Subject: [PATCH] add udebug support

Add internal debug messages and log messages to the ring buffer

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
 CMakeLists.txt |  4 ++-
 main.c         | 49 +++++++++++++++++++++++++++++++++
 netifd.h       |  3 ++
 ubus.c         | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 129 insertions(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8064485..8e86bd4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -33,11 +33,13 @@ FIND_LIBRARY(uci NAMES uci)
 FIND_LIBRARY(ubox NAMES ubox)
 FIND_LIBRARY(ubus NAMES ubus)
 FIND_LIBRARY(json NAMES json-c json)
+FIND_LIBRARY(udebug NAMES udebug)
 FIND_LIBRARY(blobmsg_json NAMES blobmsg_json)
 
-SET(LIBS ${ubox} ${ubus} ${uci} ${json} ${blobmsg_json})
+SET(LIBS ${ubox} ${ubus} ${uci} ${json} ${blobmsg_json} ${udebug})
 
 FIND_PATH(ubox_include_dir libubox/usock.h)
+FIND_PATH(udebug_include_dir udebug.h)
 INCLUDE_DIRECTORIES(${ubox_include_dir})
 
 IF (NOT DEFINED LIBNL_LIBS)
diff --git a/main.c b/main.c
index ec7b1be..403dc12 100644
--- a/main.c
+++ b/main.c
@@ -19,6 +19,8 @@
 #include <stdarg.h>
 #include <syslog.h>
 
+#include <udebug.h>
+
 #include "netifd.h"
 #include "ubus.h"
 #include "config.h"
@@ -35,6 +37,9 @@ const char *resolv_conf = DEFAULT_RESOLV_CONF;
 static char **global_argv;
 
 static struct list_head process_list = LIST_HEAD_INIT(process_list);
+static struct udebug ud;
+static struct udebug_buf udb;
+static bool udebug_enabled;
 
 #define DEFAULT_LOG_LEVEL L_NOTICE
 
@@ -63,6 +68,49 @@ netifd_delete_process(struct netifd_process *proc)
 	close(proc->log.fd.fd);
 }
 
+static void
+netifd_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 netifd_udebug_printf(const char *format, ...)
+{
+	va_list ap;
+
+	va_start(ap, format);
+	netifd_udebug_vprintf(format, ap);
+	va_end(ap);
+}
+
+void netifd_udebug_set_enabled(bool val)
+{
+	static const struct udebug_buf_meta meta = {
+		.name = "netifd_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);
+}
+
 void
 __attribute__((format(printf, 2, 0)))
 netifd_log_message(int priority, const char *format, ...)
@@ -73,6 +121,7 @@ netifd_log_message(int priority, const char *format, ...)
 		return;
 
 	va_start(vl, format);
+	netifd_udebug_vprintf(format, vl);
 	if (use_syslog)
 		vsyslog(log_class[priority], format, vl);
 	else
diff --git a/netifd.h b/netifd.h
index 9645a0a..c579e7c 100644
--- a/netifd.h
+++ b/netifd.h
@@ -70,6 +70,7 @@ enum {
 #ifdef DEBUG
 #define DPRINTF(format, ...) fprintf(stderr, "%s(%d): " format, __func__, __LINE__, ## __VA_ARGS__)
 #define D(level, format, ...) do { \
+		netifd_udebug_printf("[" #level "] %s(%d): " format,  __func__, __LINE__, ## __VA_ARGS__); \
 		if (debug_mask & (1 << (DEBUG_ ## level))) \
 				DPRINTF(format, ##__VA_ARGS__); \
 	} while (0)
@@ -95,6 +96,8 @@ struct netifd_process {
 	bool log_overflow;
 };
 
+void netifd_udebug_printf(const char *format, ...);
+void netifd_udebug_set_enabled(bool val);
 void netifd_log_message(int priority, const char *format, ...);
 
 int netifd_start_process(const char **argv, char **env, struct netifd_process *proc);
diff --git a/ubus.c b/ubus.c
index e2aa3f8..8ac395f 100644
--- a/ubus.c
+++ b/ubus.c
@@ -27,6 +27,7 @@
 struct ubus_context *ubus_ctx = NULL;
 static struct blob_buf b;
 static const char *ubus_path;
+struct ubus_subscriber udebug_sub;
 
 /* global object */
 
@@ -1365,9 +1366,74 @@ netifd_extdev_invoke(uint32_t id, const char *method, struct blob_attr *msg,
 	return ubus_invoke(ubus_ctx, id, method, msg, data_cb, data, 3000);
 }
 
+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
+netifd_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, "netifd", 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]));
+	netifd_udebug_set_enabled(en);
+}
+
+static int
+netifd_udebug_notify_cb(struct ubus_context *ctx, struct ubus_object *obj,
+			struct ubus_request_data *req, const char *method,
+			struct blob_attr *msg)
+{
+	netifd_udebug_config_cb(msg);
+
+	return 0;
+}
+
+static void
+netifd_udebug_req_cb(struct ubus_request *req, int type, struct blob_attr *msg)
+{
+	netifd_udebug_config_cb(msg);
+}
+
+static bool
+netifd_udebug_sub_cb(struct ubus_context *ctx, struct ubus_subscriber *sub,
+		     const char *path)
+{
+	return !strcmp(path, "udebug");
+}
+
 int
 netifd_ubus_init(const char *path)
 {
+	uint32_t id;
+
 	uloop_init();
 	ubus_path = path;
 
@@ -1384,6 +1450,14 @@ netifd_ubus_init(const char *path)
 	netifd_add_object(&wireless_object);
 	netifd_add_iface_object();
 
+	udebug_sub.cb = netifd_udebug_notify_cb;
+	udebug_sub.new_obj_cb = netifd_udebug_sub_cb;
+	ubus_register_subscriber(ubus_ctx, &udebug_sub);
+	if (ubus_lookup_id(ubus_ctx, "udebug", &id) == 0) {
+		ubus_subscribe(ubus_ctx, &udebug_sub, id);
+		ubus_invoke(ubus_ctx, id, "get_config", NULL, netifd_udebug_req_cb, NULL, 1000);
+	}
+
 	return 0;
 }
 
-- 
2.30.2