Const correctness and const-ref in Crypto and elsewhere.

src/network/network.cc

@@ -96,7 +96,7 @@ string Packet::tostring( Session *session )
   return session->encrypt( Message( Nonce( direction_seq ), timestamps + payload ) );
 }
 
-Packet Connection::new_packet( string &s_payload )
+Packet Connection::new_packet( const string &s_payload )
 {
   uint16_t outgoing_timestamp_reply = -1;
 
@@ -391,7 +391,7 @@ Connection::Connection( const char *key_str, const char *ip, const char *port )
   set_MTU( remote_addr.sa.sa_family );
 }
 
-void Connection::send( string s )
+void Connection::send( const string & s )
 {
   if ( !has_remote_addr ) {
     return;

src/network/network.h

@@ -82,7 +82,7 @@ namespace Network {
     string payload;
     
     Packet( Direction s_direction,
-	    uint16_t s_timestamp, uint16_t s_timestamp_reply, string s_payload )
+	    uint16_t s_timestamp, uint16_t s_timestamp_reply, const string & s_payload )
       : seq( Crypto::unique() ), direction( s_direction ),
 	timestamp( s_timestamp ), timestamp_reply( s_timestamp_reply ), payload( s_payload )
     {}
@@ -190,7 +190,7 @@ namespace Network {
     bool have_send_exception;
     NetworkException send_exception;
 
-    Packet new_packet( string &s_payload );
+    Packet new_packet( const string &s_payload );
 
     void hop_port( void );
 
@@ -209,7 +209,7 @@ namespace Network {
     Connection( const char *desired_ip, const char *desired_port ); /* server */
     Connection( const char *key_str, const char *ip, const char *port ); /* client */
 
-    void send( string s );
+    void send( const string & s );
     string recv( void );
     const std::vector< int > fds( void ) const;
     int get_MTU( void ) const { return MTU; }

src/network/transportfragment.cc

@@ -72,7 +72,7 @@ string Fragment::tostring( void )
   return ret;
 }
 
-Fragment::Fragment( string &x )
+Fragment::Fragment( const string &x )
   : id( -1 ), fragment_num( -1 ), final( false ), initialized( true ),
     contents()
 {

src/network/transportfragment.h

@@ -61,12 +61,12 @@ namespace Network {
       : id( -1 ), fragment_num( -1 ), final( false ), initialized( false ), contents()
     {}
 
-    Fragment( uint64_t s_id, uint16_t s_fragment_num, bool s_final, string s_contents )
+    Fragment( uint64_t s_id, uint16_t s_fragment_num, bool s_final, const string & s_contents )
       : id( s_id ), fragment_num( s_fragment_num ), final( s_final ), initialized( true ),
 	contents( s_contents )
     {}
 
-    Fragment( string &x );
+    Fragment( const string &x );
 
     string tostring( void );
 

src/network/transportsender.cc

@@ -229,7 +229,7 @@ void TransportSender<MyState>::add_sent_state( uint64_t the_timestamp, uint64_t
 }
 
 template <class MyState>
-void TransportSender<MyState>::send_to_receiver( string diff )
+void TransportSender<MyState>::send_to_receiver( const string & diff )
 {
   uint64_t new_num;
   if ( current_state == sent_states.back().state ) { /* previously sent */
@@ -310,7 +310,7 @@ const string TransportSender<MyState>::make_chaff( void )
 }
 
 template <class MyState>
-void TransportSender<MyState>::send_in_fragments( string diff, uint64_t new_num )
+void TransportSender<MyState>::send_in_fragments( const string & diff, uint64_t new_num )
 {
   Instruction inst;
 

src/network/transportsender.h

@@ -64,9 +64,9 @@ namespace Network {
     void update_assumed_receiver_state( void );
     void attempt_prospective_resend_optimization( string &proposed_diff );
     void rationalize_states( void );
-    void send_to_receiver( string diff );
+    void send_to_receiver( const string & diff );
     void send_empty_ack( void );
-    void send_in_fragments( string diff, uint64_t new_num );
+    void send_in_fragments( const string & diff, uint64_t new_num );
     void add_sent_state( uint64_t the_timestamp, uint64_t num, MyState &state );
 
     /* state of sender */

src/network/transportstate.h

@@ -42,7 +42,7 @@ namespace Network {
     uint64_t num;
     State state;
     
-    TimestampedState( uint64_t s_timestamp, uint64_t s_num, State &s_state )
+    TimestampedState( uint64_t s_timestamp, uint64_t s_num, const State &s_state )
       : timestamp( s_timestamp ), num( s_num ), state( s_state )
     {}