Lua loadable c library example (.so)

lua_lib/lua_lookup3.c

@@ -0,0 +1,27 @@
+#include <lua.h>
+#include <lauxlib.h>
+#include <stdint.h>
+
+uint32_t lookup3(const void *key, size_t length, uint32_t initval);
+
+// Lua wrapper
+static int l_lookup3(lua_State *L) {
+    size_t len;
+    const char *str = luaL_checklstring(L, 1, &len);  // get string + length
+    uint32_t initval = (uint32_t)luaL_checkinteger(L, 2); // get initval
+
+    uint32_t hash = lookup3(str, len, initval);
+
+    lua_pushinteger(L, hash);  // return the hash
+    return 1;                  // number of return values
+}
+
+// Module open function
+int luaopen_lookup3(lua_State *L) {
+    lua_newtable(L);
+
+    lua_pushcfunction(L, l_lookup3);
+    lua_setfield(L, -2, "lookup3");
+
+    return 1;  // return the table
+}