1 files changed, 52 insertions, 0 deletions

diff --git a/src/except.c b/src/except.c
new file mode 100644
index 0000000..c9eb20e
--- /dev/null
+++ b/src/except.c
@@ -0,0 +1,52 @@
+#include <lauxlib.h>
+#include <stdio.h>
+
+#include "except.h"
+
+static int global_try(lua_State *L);
+static int global_protect(lua_State *L);
+static int protected(lua_State *L);
+
+static luaL_reg func[] = {
+    {"try",      global_try},
+    {"protect",  global_protect},
+    {NULL,       NULL}
+};
+
+/*-------------------------------------------------------------------------*\
+* Exception handling: try method
+\*-------------------------------------------------------------------------*/
+static int global_try(lua_State *L) {
+    if (lua_isnil(L, 1) || (lua_isboolean(L, 1) && !lua_toboolean(L, 1))) {
+        lua_settop(L, 2);
+        lua_error(L);
+        return 0;
+    } else return lua_gettop(L);
+}
+
+/*-------------------------------------------------------------------------*\
+* Exception handling: protect factory
+\*-------------------------------------------------------------------------*/
+static int protected(lua_State *L) {
+    lua_pushvalue(L, lua_upvalueindex(1));
+    lua_insert(L, 1);
+    if (lua_pcall(L, lua_gettop(L) - 1, LUA_MULTRET, 0) != 0) {
+        lua_pushnil(L);
+        lua_insert(L, 1);
+        return 2;
+    } else return lua_gettop(L);
+}
+
+static int global_protect(lua_State *L) {
+    lua_insert(L, 1);
+    lua_pushcclosure(L, protected, 1);
+    return 1;
+}
+
+/*-------------------------------------------------------------------------*\
+* Init module
+\*-------------------------------------------------------------------------*/
+int except_open(lua_State *L) {
+    luaL_openlib(L, NULL, func, 0);
+    return 0;
+}