add ucitrigger: a uci plugin, command line tool and lua interface for automatically applying uci config changes

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@16375 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 182 insertions, 0 deletions

diff --git a/package/uci/patches/120-uci_trigger.patch b/package/uci/patches/120-uci_trigger.patch
new file mode 100644
index 0000000000..a1454a37b2
--- /dev/null
+++ b/package/uci/patches/120-uci_trigger.patch
@@ -0,0 +1,182 @@
+--- /dev/null
++++ b/trigger/Makefile
+@@ -0,0 +1,44 @@
++include ../Makefile.inc
++LUA_VERSION=5.1
++PREFIX_SEARCH=/usr /usr/local /opt/local
++LUA_PLUGINDIR=$(firstword \
++	$(foreach ldir,$(subst ;, ,$(shell lua -e 'print(package.cpath)')), \
++		$(if $(findstring lib/lua/,$(ldir)),$(patsubst %/?.so,%,$(ldir))) \
++	) \
++)
++
++# find lua prefix
++LUA_PREFIX=$(firstword \
++	$(foreach prefix,$(PREFIX_SEARCH),\
++		$(if $(wildcard $(prefix)/include/lua.h),$(prefix)) \
++	) \
++)
++
++libdir=$(prefix)/libs
++luadir=$(if $(LUA_PLUGINDIR),$(LUA_PLUGINDIR),$(libdir)/lua/$(LUA_VERSION))
++luainc=$(shell pkg-config --silence-errors --cflags lua$(LUA_VERSION))
++
++CPPFLAGS=-I.. $(if $(luainc),$(luainc), -I$(LUA_PREFIX)/include)
++LIBS=-L.. -luci $(shell pkg-config --silence-errors --libs lua$(LUA_VERSION))
++
++PLUGIN_LD=$(CC)
++ifeq ($(OS),Darwin)
++  PLUGIN_LDFLAGS=-bundle
++else
++  PLUGIN_LDFLAGS=-shared -Wl,-soname,$(SHLIB_FILE)
++endif
++
++all: uci_trigger.so
++
++uci_trigger.so: uci_trigger.o
++	$(PLUGIN_LD) $(PLUGIN_LDFLAGS) -o $@ $^ $(LIBS)
++
++%.o: %.c
++	$(CC) $(CPPFLAGS) $(CFLAGS) $(FPIC) -c -o $@ $<
++
++install:
++	mkdir -p $(DESTDIR)$(luadir)
++	$(INSTALL) -m0644 uci_trigger.so $(DESTDIR)$(luadir)/
++
++clean:
++	rm -f *.so *.o uci_trigger.so
+--- /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_history *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_history *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_history *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,
++};