Index: uci.git/lua/uci.c
===================================================================
--- uci.git.orig/lua/uci.c	2008-08-27 16:45:56.000000000 +0200
+++ uci.git/lua/uci.c	2008-08-27 16:55:30.000000000 +0200
@@ -24,7 +24,8 @@
 #include <lauxlib.h>
 #include <uci.h>
 
-#define MODNAME        "uci"
+#define MODNAME        "uci2"
+#define CURSOR_META    "uci2.cursor.meta"
 //#define DEBUG 1
 
 #ifdef DEBUG
@@ -33,7 +34,6 @@
 #define DPRINTF(...) do {} while (0)
 #endif
 
-static struct uci_context *ctx = NULL;
 enum autoload {
 	AUTOLOAD_OFF = 0,
 	AUTOLOAD_ON = 1,
@@ -41,7 +41,7 @@
 };
 
 static struct uci_package *
-find_package(lua_State *L, const char *str, enum autoload al)
+find_package(lua_State *L, struct uci_context *ctx, const char *str, enum autoload al)
 {
 	struct uci_package *p = NULL;
 	struct uci_element *e;
@@ -70,17 +70,8 @@
 		uci_load(ctx, name, &p);
 	else if (al) {
 		do {
-			lua_getfield(L, LUA_GLOBALSINDEX, "uci");
-			lua_getfield(L, -1, "autoload");
-			if (!lua_isboolean(L, -1))
-				break;
-
-			if (!lua_toboolean(L, -1))
-				break;
-
 			uci_load(ctx, name, &p);
 		} while (0);
-		lua_pop(L, 2);
 	}
 
 done:
@@ -89,9 +80,9 @@
 	return p;
 }
 
-static void uci_lua_perror(lua_State *L, char *name)
+static void uci_lua_perror(lua_State *L, struct uci_context *ctx, char *name)
 {
-	lua_getfield(L, LUA_GLOBALSINDEX, "uci");
+	lua_getfield(L, LUA_GLOBALSINDEX, MODNAME);
 	lua_getfield(L, -1, "warn");
 	if (!lua_isboolean(L, -1))
 		goto done;
@@ -103,33 +94,33 @@
 }
 
 static int
-lookup_args(lua_State *L, struct uci_ptr *ptr, char **buf)
+lookup_args(lua_State *L, struct uci_context *ctx, struct uci_ptr *ptr, char **buf)
 {
 	char *s = NULL;
 	int n;
 
 	n = lua_gettop(L);
-	luaL_checkstring(L, 1);
-	s = strdup(lua_tostring(L, 1));
+	luaL_checkstring(L, 2);
+	s = strdup(lua_tostring(L, 2));
 	if (!s)
 		goto error;
 
 	memset(ptr, 0, sizeof(struct uci_ptr));
-	if (!find_package(L, s, AUTOLOAD_ON))
+	if (!find_package(L, ctx, s, AUTOLOAD_ON))
 		goto error;
 
 	switch (n) {
+	case 5:
 	case 4:
-	case 3:
-		ptr->option = luaL_checkstring(L, 3);
+		ptr->option = luaL_checkstring(L, 4);
 		/* fall through */
-	case 2:
-		ptr->section = luaL_checkstring(L, 2);
-		ptr->package = luaL_checkstring(L, 1);
+	case 3:
+		ptr->section = luaL_checkstring(L, 3);
+		ptr->package = luaL_checkstring(L, 2);
 		if (uci_lookup_ptr(ctx, ptr, NULL, false) != UCI_OK)
 			goto error;
 		break;
-	case 1:
+	case 2:
 		if (uci_lookup_ptr(ctx, ptr, s, false) != UCI_OK)
 			goto error;
 		break;
@@ -202,15 +193,70 @@
 	}
 }
 
+static struct uci_context**
+uci_lua_context(lua_State *L, int index)
+{
+	struct uci_context **u = (struct uci_context **)luaL_checkudata(L, index, CURSOR_META);
+	luaL_argcheck(L, *u, index, "UCI cursor expected");
+	return u;
+}
+
+
+static int
+uci_lua_cursor(lua_State *L)
+{
+	int argc = lua_gettop(L);
+
+	/* create userdata object */
+	struct uci_context **u = (struct uci_context **)lua_newuserdata(L, sizeof(struct uci_context *));
+
+	/* set metatable for userdata */
+	luaL_getmetatable(L, CURSOR_META);
+	lua_setmetatable(L, -2);
+
+	/* initialize context */
+	*u = uci_alloc_context();
+	if (*u == NULL) {
+		luaL_error(L, "Cannot allocate UCI context");
+	}
+
+	if (argc == 2 && lua_isnoneornil(L, 2) == 0) {
+		if (uci_set_savedir(*u, luaL_checkstring(L, 2)) != 0) {
+			luaL_error(L, "Unable to set savedir");
+		}
+	}
+
+	if (argc >= 1 && lua_isnoneornil(L, 1) == 0) {
+		if (uci_set_confdir(*u, luaL_checkstring(L, 1)) != 0) {
+			luaL_error(L, "Unable to set confdir");
+		}
+	}
+
+	return 1;
+}
+
+static int
+uci_lua_gc (lua_State *L) {
+	struct uci_context **u = (struct uci_context **)luaL_checkudata(L, 1, CURSOR_META);
+
+	if (*u) {
+		uci_free_context(*u);
+		*u = NULL;
+	}
+
+	return 0;
+}
+
 static int
 uci_lua_unload(lua_State *L)
 {
+	struct uci_context *ctx = *uci_lua_context(L, 1);
 	struct uci_package *p;
 	const char *s;
 
-	luaL_checkstring(L, 1);
+	luaL_checkstring(L, 2);
 	s = lua_tostring(L, -1);
-	p = find_package(L, s, AUTOLOAD_OFF);
+	p = find_package(L, ctx, s, AUTOLOAD_OFF);
 	if (p) {
 		uci_unload(ctx, p);
 		lua_pushboolean(L, 1);
@@ -223,6 +269,7 @@
 static int
 uci_lua_load(lua_State *L)
 {
+	struct uci_context *ctx = *uci_lua_context(L, 1);
 	struct uci_package *p = NULL;
 	const char *s;
 
@@ -231,7 +278,7 @@
 	s = lua_tostring(L, -1);
 
 	if (uci_load(ctx, s, &p)) {
-		uci_lua_perror(L, "uci.load");
+		uci_lua_perror(L, ctx, "uci.load");
 		lua_pushboolean(L, 0);
 	} else {
 		lua_pushboolean(L, 1);
@@ -244,22 +291,23 @@
 static int
 uci_lua_foreach(lua_State *L)
 {
+	struct uci_context *ctx = *uci_lua_context(L, 1);
 	struct uci_package *p;
 	struct uci_element *e;
 	const char *package, *type;
 	bool ret = false;
 
-	package = luaL_checkstring(L, 1);
+	package = luaL_checkstring(L, 2);
 
-	if (lua_isnil(L, 2))
+	if (lua_isnil(L, 3))
 		type = NULL;
 	else
-		type = luaL_checkstring(L, 2);
+		type = luaL_checkstring(L, 3);
 
-	if (!lua_isfunction(L, 3) || !package)
+	if (!lua_isfunction(L, 4) || !package)
 		luaL_error(L, "Invalid argument");
 
-	p = find_package(L, package, AUTOLOAD_ON);
+	p = find_package(L, ctx, package, AUTOLOAD_ON);
 	if (!p)
 		goto done;
 
@@ -269,7 +317,7 @@
 		if (type && (strcmp(s->type, type) != 0))
 			continue;
 
-		lua_pushvalue(L, 3); /* iterator function */
+		lua_pushvalue(L, 4); /* iterator function */
 		uci_push_section(L, s);
 		if (lua_pcall(L, 1, 0, 0) == 0)
 			ret = true;
@@ -283,12 +331,13 @@
 static int
 uci_lua_get_any(lua_State *L, bool all)
 {
+	struct uci_context *ctx = *uci_lua_context(L, 1);
 	struct uci_element *e = NULL;
 	struct uci_ptr ptr;
 	char *s = NULL;
 	int err = UCI_ERR_NOTFOUND;
 
-	if (lookup_args(L, &ptr, &s))
+	if (lookup_args(L, ctx, &ptr, &s))
 		goto error;
 
 	uci_lookup_ptr(ctx, &ptr, NULL, false);
@@ -327,7 +376,7 @@
 	switch(err) {
 	default:
 		ctx->err = err;
-		uci_lua_perror(L, "uci.get");
+		uci_lua_perror(L, ctx, "uci.get");
 		/* fall through */
 	case UCI_ERR_NOTFOUND:
 		lua_pushnil(L);
@@ -352,6 +401,7 @@
 static int
 uci_lua_add(lua_State *L)
 {
+	struct uci_context *ctx = *uci_lua_context(L, 1);
 	struct uci_section *s = NULL;
 	struct uci_package *p;
 	const char *package;
@@ -359,9 +409,9 @@
 	const char *name = NULL;
 
 	do {
-		package = luaL_checkstring(L, 1);
-		type = luaL_checkstring(L, 2);
-		p = find_package(L, package, AUTOLOAD_ON);
+		package = luaL_checkstring(L, 2);
+		type = luaL_checkstring(L, 3);
+		p = find_package(L, ctx, package, AUTOLOAD_ON);
 		if (!p)
 			break;
 
@@ -378,11 +428,11 @@
 static int
 uci_lua_delete(lua_State *L)
 {
+	struct uci_context *ctx = *uci_lua_context(L, 1);
 	struct uci_ptr ptr;
 	char *s = NULL;
 	int err = UCI_ERR_NOTFOUND;
-
-	if (lookup_args(L, &ptr, &s))
+	if (lookup_args(L, ctx, &ptr, &s))
 		goto error;
 
 	err = uci_delete(ctx, &ptr);
@@ -391,7 +441,7 @@
 	if (s)
 		free(s);
 	if (err)
-		uci_lua_perror(L, "uci.delete");
+		uci_lua_perror(L, ctx, "uci.delete");
 	lua_pushboolean(L, (err == 0));
 	return 1;
 }
@@ -399,6 +449,7 @@
 static int
 uci_lua_set(lua_State *L)
 {
+	struct uci_context *ctx = *uci_lua_context(L, 1);
 	bool istable = false;
 	struct uci_ptr ptr;
 	int err = UCI_ERR_MEM;
@@ -406,14 +457,14 @@
 	int i, nargs;
 
 	nargs = lua_gettop(L);
-	if (lookup_args(L, &ptr, &s))
+	if (lookup_args(L, ctx, &ptr, &s))
 		goto error;
 
 	switch(nargs) {
-	case 1:
+	case 2:
 		/* Format: uci.set("p.s.o=v") or uci.set("p.s=v") */
 		break;
-	case 4:
+	case 5:
 		/* Format: uci.set("p", "s", "o", "v") */
 		if (lua_istable(L, nargs)) {
 			if (lua_objlen(L, nargs) < 1)
@@ -426,7 +477,7 @@
 			ptr.value = luaL_checkstring(L, nargs);
 		}
 		break;
-	case 3:
+	case 4:
 		/* Format: uci.set("p", "s", "v") */
 		ptr.value = ptr.option;
 		ptr.option = NULL;
@@ -462,7 +513,7 @@
 
 error:
 	if (err)
-		uci_lua_perror(L, "uci.set");
+		uci_lua_perror(L, ctx, "uci.set");
 	lua_pushboolean(L, (err == 0));
 	return 1;
 }
@@ -476,6 +527,7 @@
 static int
 uci_lua_package_cmd(lua_State *L, enum pkg_cmd cmd)
 {
+	struct uci_context *ctx = *uci_lua_context(L, 1);
 	struct uci_element *e, *tmp;
 	struct uci_ptr ptr;
 	char *s = NULL;
@@ -483,10 +535,10 @@
 	int nargs;
 
 	nargs = lua_gettop(L);
-	if ((cmd != CMD_REVERT) && (nargs > 1))
+	if ((cmd != CMD_REVERT) && (nargs > 2))
 		goto err;
 
-	if (lookup_args(L, &ptr, &s))
+	if (lookup_args(L, ctx, &ptr, &s))
 		goto err;
 
 	uci_lookup_ptr(ctx, &ptr, NULL, false);
@@ -566,16 +618,16 @@
 }
 
 static void
-uci_lua_changes_pkg(lua_State *L, const char *package)
+uci_lua_changes_pkg(lua_State *L, struct uci_context *ctx, const char *package)
 {
 	struct uci_package *p = NULL;
 	struct uci_element *e;
 	bool autoload = false;
 
-	p = find_package(L, package, AUTOLOAD_OFF);
+	p = find_package(L, ctx, package, AUTOLOAD_OFF);
 	if (!p) {
 		autoload = true;
-		p = find_package(L, package, AUTOLOAD_FORCE);
+		p = find_package(L, ctx, package, AUTOLOAD_FORCE);
 		if (!p)
 			return;
 	}
@@ -600,6 +652,7 @@
 static int
 uci_lua_changes(lua_State *L)
 {
+	struct uci_context *ctx = *uci_lua_context(L, 1);
 	const char *package = NULL;
 	char **config = NULL;
 	int nargs;
@@ -607,9 +660,9 @@
 
 	nargs = lua_gettop(L);
 	switch(nargs) {
+	case 2:
+		package = luaL_checkstring(L, 2);
 	case 1:
-		package = luaL_checkstring(L, 1);
-	case 0:
 		break;
 	default:
 		luaL_error(L, "invalid argument count");
@@ -617,13 +670,13 @@
 
 	lua_newtable(L);
 	if (package) {
-		uci_lua_changes_pkg(L, package);
+		uci_lua_changes_pkg(L, ctx, package);
 	} else {
 		if (uci_list_configs(ctx, &config) != 0)
 			goto done;
 
 		for(i = 0; config[i] != NULL; i++) {
-			uci_lua_changes_pkg(L, config[i]);
+			uci_lua_changes_pkg(L, ctx, config[i]);
 		}
 	}
 
@@ -632,29 +685,53 @@
 }
 
 static int
+uci_lua_get_confdir(lua_State *L)
+{
+	struct uci_context *ctx = *uci_lua_context(L, 1);
+	lua_pushstring(L, ctx->confdir);
+	return 1;
+}
+
+static int
 uci_lua_set_confdir(lua_State *L)
 {
+	struct uci_context *ctx = *uci_lua_context(L, 1);
 	int ret;
 
-	luaL_checkstring(L, 1);
+	luaL_checkstring(L, 2);
 	ret = uci_set_confdir(ctx, lua_tostring(L, -1));
 	lua_pushboolean(L, (ret == 0));
 	return 1;
 }
 
 static int
+uci_lua_get_savedir(lua_State *L)
+{
+	struct uci_context *ctx = *uci_lua_context(L, 1);
+	lua_pushstring(L, ctx->savedir);
+	return 1;
+}
+
+static int
 uci_lua_set_savedir(lua_State *L)
 {
+	struct uci_context *ctx = *uci_lua_context(L, 1);
 	int ret;
 
-	luaL_checkstring(L, 1);
+	luaL_checkstring(L, 2);
 	ret = uci_set_savedir(ctx, lua_tostring(L, -1));
 	lua_pushboolean(L, (ret == 0));
 
 	return 1;
 }
 
-static const luaL_Reg uci[] = {
+static const luaL_Reg uci_module[] = {
+	{ "cursor", uci_lua_cursor },
+	{ NULL, NULL },
+};
+
+static const luaL_Reg uci_cursor[] = {
+	{ "__gc", uci_lua_gc },
 	{ "load", uci_lua_load },
 	{ "unload", uci_lua_unload },
 	{ "get", uci_lua_get },
@@ -667,25 +744,33 @@
 	{ "revert", uci_lua_revert },
 	{ "changes", uci_lua_changes },
 	{ "foreach", uci_lua_foreach },
+	{ "get_confdir", uci_lua_get_confdir },
+	{ "get_savedir", uci_lua_get_savedir },
 	{ "set_confdir", uci_lua_set_confdir },
 	{ "set_savedir", uci_lua_set_savedir },
 	{ NULL, NULL },
 };
 
-
 int
-luaopen_uci(lua_State *L)
+luaopen_uci2(lua_State *L)
 {
-	ctx = uci_alloc_context();
-	if (!ctx)
-		luaL_error(L, "Cannot allocate UCI context\n");
-	luaL_register(L, MODNAME, uci);
-
-	/* enable autoload by default */
-	lua_getfield(L, LUA_GLOBALSINDEX, "uci");
-	lua_pushboolean(L, 1);
-	lua_setfield(L, -2, "autoload");
-	lua_pop(L, 1);
+	/* Create metatable */
+	luaL_newmetatable(L, CURSOR_META);
 
-	return 0;
+	/* metatable.__index = metatable */
+    lua_pushstring(L, "__index");
+    lua_pushvalue(L, -2);
+    lua_settable(L, -3);
+
+    /* fill and drop metatable */
+    luaL_register(L, NULL, uci_cursor);
+    lua_pop(L, 1);
+
+    /* register module table */
+	luaL_register(L, MODNAME, uci_module);
+	lua_pushliteral(L, "APIVERSION");
+	lua_pushinteger(L, 2);
+	lua_settable(L, -3);
+
+	return 1;
 }