1 files changed, 90 insertions, 0 deletions
diff --git a/daemon/bindings/impl.h b/daemon/bindings/impl.h
new file mode 100644
index 0000000..d522756
--- /dev/null
+++ b/daemon/bindings/impl.h
@@ -0,0 +1,90 @@
+/*  Copyright (C) CZ.NIC, z.s.p.o. <knot-resolver@labs.nic.cz>
+ *  SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#pragma once
+
+#include "daemon/engine.h"
+#include "daemon/worker.h" /* the_worker is often useful */
+
+#include <lua.h>
+#include <lauxlib.h>
+/* It may happen that include files are messed up and we're hitting a header
+ * e.g. from vanilla Lua.  Even 5.1 won't work due to missing luaL_traceback() in <lauxlib.h>. */
+#if (LUA_VERSION_NUM) != 501 || !defined(LUA_LJDIR)
+	#error "Incorrect Lua version in #include <lua.h> - LuaJIT compatible with Lua 5.1 is required"
+#endif
+
+
+/** Useful to stringify macros into error strings. */
+#define STR(s) STRINGIFY_TOKEN(s)
+#define STRINGIFY_TOKEN(s) #s
+
+
+/** Check lua table at the top of the stack for allowed keys.
+ * \param keys NULL-terminated array of 0-terminated strings
+ * \return NULL if passed or the offending string (pushed on top of lua stack)
+ * \note Future work: if non-NULL is returned, there's extra stuff on the lua stack.
+ * \note Brute-force complexity: table length * summed length of keys.
+ */
+const char * lua_table_checkindices(lua_State *L, const char *keys[]);
+
+/** If the value at the top of the stack isn't a table, make it a single-element list. */
+static inline void lua_listify(lua_State *L)
+{
+	if (lua_istable(L, -1))
+		return;
+	lua_createtable(L, 1, 0);
+	lua_insert(L, lua_gettop(L) - 1); /* swap the top two stack elements */
+	lua_pushinteger(L, 1);
+	lua_insert(L, lua_gettop(L) - 1); /* swap the top two stack elements */
+	lua_settable(L, -3);
+}
+
+
+/** Throw a formatted lua error.
+ *
+ * The message will get prefixed by "ERROR: " and supplemented by stack trace.
+ * \return never!  It calls lua_error().
+ *
+ * Example:
+	ERROR: not a valid pin_sha256: 'a1Z/3ek=', raw length 5 instead of 32
+	stack traceback:
+		[C]: in function 'tls_client'
+		/PathToPREFIX/lib/kdns_modules/policy.lua:175: in function 'TLS_FORWARD'
+		/PathToConfig.lua:46: in main chunk
+ */
+KR_PRINTF(2) KR_NORETURN KR_COLD
+void lua_error_p(lua_State *L, const char *fmt, ...);
+/** @internal Annotate for static checkers. */
+KR_NORETURN int lua_error(lua_State *L);
+
+/** Shortcut for common case. */
+static inline void lua_error_maybe(lua_State *L, int err)
+{
+	if (err) lua_error_p(L, "%s", kr_strerror(err));
+}
+
+static inline int execute_callback(lua_State *L, int argc)
+{
+	int ret = engine_pcall(L, argc);
+	if (ret != 0) {
+		kr_log_error(SYSTEM, "error: %s\n", lua_tostring(L, -1));
+	}
+	/* Clear the stack, there may be event a/o anything returned */
+	lua_settop(L, 0);
+	return ret;
+}
+
+/** Push a pointer as heavy/full userdata.
+ *
+ * It's useful as a replacement of lua_pushlightuserdata(),
+ * but note that it behaves differently in lua (converts to pointer-to-pointer).
+ */
+static inline void lua_pushpointer(lua_State *L, void *p)
+{
+       void **addr = lua_newuserdata(L, sizeof(void *));
+       kr_require(addr);
+       memcpy(addr, &p, sizeof(void *));
+}
+