ruleset: improve error handling in aux_todialreq

Signed-off-by: He Xian <[email protected]>

src/ruleset.c

@@ -83,7 +83,7 @@ static int ruleset_luainit(lua_State *restrict L)
 	const char *strings[] = {
 		ERR_MEMORY,
 		ERR_BAD_REGISTRY,
-		ERR_INVALID_ROUTE,
+		ERR_INVALID_INVOKE,
 		ERR_NOT_ASYNC_ROUTINE,
 	};
 	const int nstrings = (int)ARRAY_SIZE(strings);

src/ruleset/api.c

@@ -4,6 +4,7 @@
 #include "api.h"
 
 #include "net/addr.h"
+#include "utils/debug.h"
 #include "utils/minmax.h"
 #include "utils/serialize.h"
 
@@ -31,10 +32,15 @@ static int api_invoke(lua_State *restrict L)
 {
 	size_t len;
 	const char *code = luaL_checklstring(L, 1, &len);
+	(void)luaL_checkstring(L, 2);
 	const int n = lua_gettop(L) - 1;
-	struct dialreq *req = aux_todialreq(L, n);
+	if (!aux_todialreq(L, n)) {
+		lua_pushliteral(L, ERR_INVALID_INVOKE);
+		return lua_error(L);
+	}
+	struct dialreq *req = lua_touserdata(L, -1);
 	if (req == NULL) {
-		lua_pushliteral(L, ERR_INVALID_ROUTE);
+		lua_pushliteral(L, ERR_INVALID_INVOKE);
 		return lua_error(L);
 	}
 	struct ruleset *restrict r = aux_getruleset(L);

src/ruleset/await.c

@@ -304,9 +304,13 @@ static int await_invoke(lua_State *restrict L)
 	size_t len;
 	const char *code = luaL_checklstring(L, 1, &len);
 	const int n = lua_gettop(L) - 1;
-	struct dialreq *req = aux_todialreq(L, n);
+	if (!aux_todialreq(L, n)) {
+		lua_pushliteral(L, ERR_INVALID_INVOKE);
+		return lua_error(L);
+	}
+	struct dialreq *req = lua_touserdata(L, -1);
 	if (req == NULL) {
-		lua_pushliteral(L, ERR_INVALID_ROUTE);
+		lua_pushliteral(L, ERR_INVALID_INVOKE);
 		return lua_error(L);
 	}
 	struct ruleset *restrict r = aux_getruleset(L);

src/ruleset/base.c

@@ -86,52 +86,52 @@ int aux_format_addr(lua_State *restrict L)
 	return 1;
 }
 
-struct dialreq *aux_todialreq(lua_State *restrict L, const int n)
+bool aux_todialreq(lua_State *restrict L, const int n)
 {
 	/* lua stack: ... addr proxyN ... proxy1 */
 	if (n < 1) {
 		lua_pushlightuserdata(L, NULL);
-		return NULL;
+		return true;
+	}
+	if (lua_isnil(L, -1)) {
+		lua_pop(L, n);
+		lua_pushlightuserdata(L, NULL);
+		return true;
 	}
 	struct dialreq *req = dialreq_new((size_t)(n - 1));
 	if (req == NULL) {
 		LOGOOM();
 		lua_pop(L, n);
-		lua_pushlightuserdata(L, NULL);
-		return NULL;
+		return false;
 	}
 	size_t len;
 	for (int i = 1; i < n; i++) {
 		const char *s = lua_tolstring(L, -i, &len);
 		if (s == NULL) {
 			dialreq_free(req);
 			lua_pop(L, n);
-			lua_pushlightuserdata(L, NULL);
-			return NULL;
+			return false;
 		}
 		if (!dialreq_addproxy(req, s, len)) {
 			dialreq_free(req);
 			lua_pop(L, n);
-			lua_pushlightuserdata(L, NULL);
-			return NULL;
+			return false;
 		}
 	}
 	const char *s = lua_tolstring(L, -n, &len);
 	if (s == NULL) {
 		dialreq_free(req);
 		lua_pop(L, n);
-		lua_pushlightuserdata(L, NULL);
-		return NULL;
+		return false;
 	}
 	if (!dialaddr_parse(&req->addr, s, len)) {
 		dialreq_free(req);
 		lua_pop(L, n);
-		lua_pushlightuserdata(L, NULL);
-		return NULL;
+		return false;
 	}
 	lua_pop(L, n);
 	lua_pushlightuserdata(L, req);
-	return req;
+	return true;
 }
 
 int aux_traceback(lua_State *restrict L)

src/ruleset/base.h

@@ -33,7 +33,7 @@ enum ruleset_ridx {
 
 #define ERR_MEMORY "out of memory"
 #define ERR_BAD_REGISTRY "Lua registry is corrupted"
-#define ERR_INVALID_ROUTE "unable to parse route"
+#define ERR_INVALID_INVOKE "invalid invocation target"
 #define ERR_NOT_ASYNC_ROUTINE "not in asynchronous routine"
 
 struct ruleset *aux_getruleset(lua_State *L);
@@ -43,8 +43,8 @@ const char *aux_reader(lua_State *L, void *ud, size_t *sz);
 /* [-1, +1, v] */
 int aux_format_addr(lua_State *L);
 
-/* [-n, +1, -] */
-struct dialreq *aux_todialreq(lua_State *L, int n);
+/* [-n, +(0|1), -] */
+bool aux_todialreq(lua_State *L, int n);
 
 int aux_traceback(lua_State *L);
 

src/ruleset/cfunc.c

@@ -38,8 +38,7 @@ int cfunc_request(lua_State *restrict L)
 	if (n < 1) {
 		return 0;
 	}
-	struct dialreq *req = aux_todialreq(L, n);
-	if (req == NULL) {
+	if (!aux_todialreq(L, n)) {
 		LOGW_F("ruleset.%s `%s': invalid return", func, request);
 	}
 	return 1;