1 files changed, 11 insertions, 0 deletions

diff --git a/src/eyetil.h b/src/eyetil.h
index 03b9ba8..7517ba6 100644
--- a/src/eyetil.h
+++ b/src/eyetil.h
@@ -54,24 +54,35 @@ struct md5_digester {
     };
 
     template<typename T>
     update_iterator<T> updater() {
 	return update_iterator<T>(this);
     }
 
 };
 template<> inline void md5_digester::update<binary_t>(const binary_t& x) {
     update((const unsigned char*)&(x.front()),x.size());
 }
 
+#pragma pack(1)
+struct block512_t {
+    enum { words = 512 / sizeof(uint16_t) };
+    uint16_t data[words];
+
+    inline uint8_t *dptr(size_t o) { return ((uint8_t*)this)+o; }
+
+    static uint16_t tcpcksum(block512_t& data);
+};
+#pragma pack()
+
 class tmpdir_t {
     public:
 	std::string dir;
 
 	tmpdir_t(const std::string& dt);
 	~tmpdir_t();
 
 	std::string get_file(const std::string& f);
 };
 
 class tarchive_t {
     public: