openwrt-xburst/package/uci/patches/120-uci_trigger.patch

--- /dev/null
+++ b/trigger/uci_trigger.c
@@ -0,0 +1,132 @@
+#include <sys/types.h>
+#include <sys/time.h>
+#include <stdbool.h>
+#include <string.h>
+#include <stdio.h>
+#include <lualib.h>
+#include <lauxlib.h>
+#include "uci.h"
+
+// #define DEBUG
+
+static int refcount = 0;
+static lua_State *gL = NULL;
+static bool prepared = false;
+
+struct trigger_set_op {
+	struct uci_package *p;
+	struct uci_delta *h;
+};
+
+static int trigger_set(lua_State *L)
+{
+	struct trigger_set_op *so =
+		(struct trigger_set_op *)lua_touserdata(L, 1);
+	struct uci_package *p = so->p;
+	struct uci_delta *h = so->h;
+	struct uci_context *ctx = p->ctx;
+
+	/* ignore non-standard savedirs/configdirs
+	 * in order to not trigger events on uci state changes */
+	if (strcmp(ctx->savedir, UCI_SAVEDIR) ||
+		strcmp(ctx->confdir, UCI_CONFDIR))
+		return 0;
+
+	if (!prepared) {
+		lua_getglobal(L, "require");
+		lua_pushstring(L, "uci.trigger");
+		lua_call(L, 1, 0);
+
+		lua_getglobal(L, "uci");
+		lua_getfield(L, -1, "trigger");
+		lua_getfield(L, -1, "load_modules");
+		lua_call(L, 0, 0);
+		prepared = true;
+	} else {
+		lua_getglobal(L, "uci");
+		lua_getfield(L, -1, "trigger");
+	}
+
+	lua_getfield(L, -1, "set");
+	lua_createtable(L, 4, 0);
+
+	lua_pushstring(L, p->e.name);
+	lua_rawseti(L, -2, 1);
+	if (h->section) {
+		lua_pushstring(L, h->section);
+		lua_rawseti(L, -2, 2);
+	}
+	if (h->e.name) {
+		lua_pushstring(L, h->e.name);
+		lua_rawseti(L, -2, 3);
+	}
+	if (h->value) {
+		lua_pushstring(L, h->value);
+		lua_rawseti(L, -2, 4);
+	}
+	lua_call(L, 1, 0);
+	lua_pop(L, 2);
+	return 0;
+}
+
+#ifdef DEBUG
+
+static int report (lua_State *L, int status) {
+	if (status && !lua_isnil(L, -1)) {
+		const char *msg = lua_tostring(L, -1);
+		if (msg == NULL) msg = "(error object is not a string)";
+		fprintf(stderr, "ERROR: %s\n", msg);
+		lua_pop(L, 1);
+	}
+	return status;
+}
+
+#else
+
+static inline int report(lua_State *L, int status) {
+	return status;
+}
+
+#endif
+
+static void trigger_set_hook(const struct uci_hook_ops *ops, struct uci_package *p, struct uci_delta *h)
+{
+	struct trigger_set_op so;
+
+	so.p = p;
+	so.h = h;
+	report(gL, lua_cpcall(gL, &trigger_set, &so));
+}
+
+static struct uci_hook_ops hook = {
+	.set = trigger_set_hook,
+};
+
+static int trigger_attach(struct uci_context *ctx)
+{
+	if (!gL) {
+		gL = luaL_newstate();
+		if (!gL)
+			return -1;
+		luaL_openlibs(gL);
+
+		refcount++;
+	}
+	uci_add_hook(ctx, &hook);
+	return 0;
+}
+
+static void trigger_detach(struct uci_context *ctx)
+{
+	if (gL && (--refcount <= 0)) {
+		lua_close(gL);
+		gL = NULL;
+		refcount = 0;
+		prepared = false;
+	}
+}
+
+struct uci_plugin_ops uci_plugin = {
+	.attach = trigger_attach,
+	.detach = trigger_detach,
+};
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -35,6 +35,7 @@ ADD_EXECUTABLE(ucimap-example ucimap-exa
 TARGET_LINK_LIBRARIES(ucimap-example uci-static ucimap dl)
 
 ADD_SUBDIRECTORY(lua)
+ADD_SUBDIRECTORY(trigger)
 
 INSTALL(FILES uci.h uci_config.h ucimap.h
 	DESTINATION include/libubox
--- /dev/null
+++ b/trigger/CMakeLists.txt
@@ -0,0 +1,19 @@
+cmake_minimum_required(VERSION 2.6)
+
+PROJECT(uci C)
+
+SET(CMAKE_INSTALL_PREFIX /)
+
+ADD_DEFINITIONS(-Os -Wall -Werror --std=gnu99 -g3 -I..)
+
+IF(APPLE)
+	SET(CMAKE_SHARED_MODULE_CREATE_C_FLAGS "${CMAKE_SHARED_MODULE_CREATE_C_FLAGS} -undefined dynamic_lookup")
+ENDIF(APPLE)
+
+ADD_LIBRARY(uci_trigger MODULE uci_trigger.c)
+SET_TARGET_PROPERTIES(uci_trigger PROPERTIES
+	OUTPUT_NAME uci_trigger
+	PREFIX ""
+)
+TARGET_LINK_LIBRARIES(uci_trigger uci)
+