Adapting attribute serialization when talking to Broccoli.

Broccoli doesn't support expressions, and we now no longer send them
when serializing attributes. This is the Bro change mentioned in #606.
It's needs a correspondinly modified Broccoli identifying itself as
such, and it isn't tested yet ...

Addresses #606.

src/Attr.cc

@@ -481,7 +481,11 @@ bool Attributes::DoSerialize(SerialInfo* info) const
 	loop_over_list((*attrs), i)
 		{
 		Attr* a = (*attrs)[i];
-		SERIALIZE_OPTIONAL(a->AttrExpr())
+
+		// Broccoli doesn't support expressions.
+		Expr* e = (! info->broccoli_peer) ? a->AttrExpr() : 0;
+		SERIALIZE_OPTIONAL(e);
+
 		if ( ! SERIALIZE(char(a->Tag())) )
 			return false;
 		}

src/RemoteSerializer.cc

@@ -385,6 +385,9 @@ inline void RemoteSerializer::SetupSerialInfo(SerialInfo* info, Peer* peer)
 	     peer->phase == Peer::RUNNING )
 		info->new_cache_strategy = true;
 
+	if ( (peer->caps & Peer::BROCCOLI_PEER) )
+		info->broccoli_peer = true;
+
 	info->include_locations = false;
 	}
 
@@ -2113,6 +2116,9 @@ bool RemoteSerializer::HandshakeDone(Peer* peer)
 	if ( (peer->caps & Peer::NEW_CACHE_STRATEGY) )
 		Log(LogInfo, "peer supports keep-in-cache; using that", peer);
 
+	if ( (peer->caps & Peer::BROCCOLI_PEER) )
+		Log(LogInfo, "peer is a Broccoli", peer);
+
 	if ( peer->logs_requested )
 		log_mgr->SendAllWritersTo(peer->id);
 
@@ -2365,6 +2371,9 @@ bool RemoteSerializer::ProcessSerialization()
 	     current_peer->phase == Peer::RUNNING )
 		info.new_cache_strategy = true;
 
+	if ( current_peer->caps & Peer::BROCCOLI_PEER )
+		info.broccoli_peer = true;
+
 	if ( ! forward_remote_state_changes )
 		ignore_accesses = true;
 

src/RemoteSerializer.h

@@ -198,6 +198,7 @@ protected:
 		static const int NO_CACHING = 2;
 		static const int PID_64BIT = 4;
 		static const int NEW_CACHE_STRATEGY = 8;
+		static const int BROCCOLI_PEER = 16;
 
 		// Constants to remember to who did something.
 		static const int NONE = 0;

src/SerialInfo.h

@@ -15,6 +15,7 @@ public:
 		pid_32bit = false;
 		include_locations = true;
 		new_cache_strategy = false;
+		broccoli_peer = false;
 		}
 
 	SerialInfo(const SerialInfo& info)
@@ -28,6 +29,7 @@ public:
 		pid_32bit = info.pid_32bit;
 		include_locations = info.include_locations;
 		new_cache_strategy = info.new_cache_strategy;
+		broccoli_peer = info.broccoli_peer;
 		}
 
 	// Parameters that control serialization.
@@ -46,6 +48,11 @@ public:
 	// If true, we support keeping objs in cache permanently.
 	bool new_cache_strategy;
 
+	// If true, we're connecting to a Broccoli. If so, serialization
+	// specifics may be adapted for functionality Broccoli does not
+	// support.
+	bool broccoli_peer;
+
 	ChunkedIO::Chunk* chunk; // chunk written right before the serialization
 
 	// Attributes set during serialization.
@@ -70,6 +77,7 @@ public:
 		print = 0;
 		pid_32bit = false;
 		new_cache_strategy = false;
+		broccoli_peer = false;
 		}
 
 	UnserialInfo(const UnserialInfo& info)
@@ -86,6 +94,7 @@ public:
 		print = info.print;
 		pid_32bit = info.pid_32bit;
 		new_cache_strategy = info.new_cache_strategy;
+		broccoli_peer = info.broccoli_peer;
 		}
 
 	// Parameters that control unserialization.
@@ -106,6 +115,11 @@ public:
 	// If true, we support keeping objs in cache permanently.
 	bool new_cache_strategy;
 
+	// If true, we're connecting to a Broccoli. If so, serialization
+	// specifics may be adapted for functionality Broccoli does not
+	// support.
+	bool broccoli_peer;
+
 	// If a global ID already exits, of these policies is used.
 	enum {
 		Keep,	// keep the old ID and ignore the new