Inverted control flow, engine as library

luprex/core/cpp/streambuffer.cpp

@@ -111,6 +111,19 @@ void StreamBuffer::clear() {
     lua_reader_size_ = 0;
 }
 
+std::string StreamBuffer::readline() {
+    char *p = read_cursor_;
+    while ((p < write_cursor_) && (*p != '\n')) p++;
+    if (p == write_cursor_) {
+        return "";
+    } else {
+        p++;
+        std::string result(read_cursor_, p - read_cursor_);
+        read_cursor_ = p;
+        return result;
+    }
+}
+
 // These routines return true if you can losslessly cast the
 // specified value to the specified type.