Initial import

util.c

@@ -0,0 +1,37 @@
+/*
+ * util.c
+ *
+ * Utility functions.
+ * See util.h for a description
+ * of these functions.
+ */
+
+#include <util.h>
+
+#include <string.h>
+
+#include <lua.h>
+#include <lauxlib.h>
+
+int lfail(lua_State *L, const char* mesg)
+{
+	luaL_pushfail(L);
+	lua_pushstring(L, mesg);
+	return LFAIL_RET;
+}
+
+void strprepend(char *s, const char *t)
+{
+    size_t len = strlen(t);
+    memmove(s + len, s, strlen(s) + 1);
+    memcpy(s, t, len);
+}
+
+void strslice(const char *s, char *buf, size_t start, size_t end)
+{
+	size_t j = 0;
+	for (size_t i = start; i <= end; ++i) {
+		buf[j++] = s[i];
+	}
+	buf[j] = 0;
+}