Codechange: use SLE_STRUCT(LIST) for Linkgraph chunks

2 files changed, 106 insertions, 90 deletions

diff --git a/src/linkgraph/linkgraph.h b/src/linkgraph/linkgraph.h
index 5eb85e4c3..a11b67a52 100644
--- a/src/linkgraph/linkgraph.h
+++ b/src/linkgraph/linkgraph.h
@@ -527,7 +527,8 @@ protected:
 	friend class LinkGraph::Node;
 	friend SaveLoadTable GetLinkGraphDesc();
 	friend SaveLoadTable GetLinkGraphJobDesc();
-	friend void SaveLoad_LinkGraph(LinkGraph &lg);
+	friend class SlLinkgraphNode;
+	friend class SlLinkgraphEdge;
 
 	CargoID cargo;         ///< Cargo of this component's link graph.
 	Date last_compression; ///< Last time the capacities and supplies were compressed.
diff --git a/src/saveload/linkgraph_sl.cpp b/src/saveload/linkgraph_sl.cpp
index 4fcc36e96..cf0292e6e 100644
--- a/src/saveload/linkgraph_sl.cpp
+++ b/src/saveload/linkgraph_sl.cpp
@@ -21,6 +21,79 @@ typedef LinkGraph::BaseNode Node;
 typedef LinkGraph::BaseEdge Edge;
 
 static uint16 _num_nodes;
+static LinkGraph *_linkgraph; ///< Contains the current linkgraph being saved/loaded.
+static NodeID _linkgraph_from; ///< Contains the current "from" node being saved/loaded.
+
+class SlLinkgraphEdge : public DefaultSaveLoadHandler<SlLinkgraphEdge, Node> {
+public:
+	inline static const SaveLoad description[] = {
+		SLE_CONDNULL(4, SL_MIN_VERSION, SLV_191), // distance
+		    SLE_VAR(Edge, capacity,                 SLE_UINT32),
+		    SLE_VAR(Edge, usage,                    SLE_UINT32),
+		    SLE_VAR(Edge, last_unrestricted_update, SLE_INT32),
+		SLE_CONDVAR(Edge, last_restricted_update,   SLE_INT32, SLV_187, SL_MAX_VERSION),
+		    SLE_VAR(Edge, next_edge,                SLE_UINT16),
+	};
+
+	void Save(Node *bn) const override
+	{
+		for (NodeID to = _linkgraph_from; to != INVALID_NODE; to = _linkgraph->edges[_linkgraph_from][to].next_edge) {
+			SlObject(&_linkgraph->edges[_linkgraph_from][to], this->GetDescription());
+		}
+	}
+
+	void Load(Node *bn) const override
+	{
+		uint16 max_size = _linkgraph->Size();
+
+		if (IsSavegameVersionBefore(SLV_191)) {
+			/* We used to save the full matrix ... */
+			for (NodeID to = 0; to < max_size; ++to) {
+				SlObject(&_linkgraph->edges[_linkgraph_from][to], this->GetDescription());
+			}
+			return;
+		}
+
+		/* ... but as that wasted a lot of space we save a sparse matrix now. */
+		for (NodeID to = _linkgraph_from; to != INVALID_NODE; to = _linkgraph->edges[_linkgraph_from][to].next_edge) {
+			if (to >= max_size) SlErrorCorrupt("Link graph structure overflow");
+			SlObject(&_linkgraph->edges[_linkgraph_from][to], this->GetDescription());
+		}
+	}
+};
+
+class SlLinkgraphNode : public DefaultSaveLoadHandler<SlLinkgraphNode, LinkGraph> {
+public:
+	inline static const SaveLoad description[] = {
+		SLE_CONDVAR(Node, xy,          SLE_UINT32, SLV_191, SL_MAX_VERSION),
+		    SLE_VAR(Node, supply,      SLE_UINT32),
+		    SLE_VAR(Node, demand,      SLE_UINT32),
+		    SLE_VAR(Node, station,     SLE_UINT16),
+		    SLE_VAR(Node, last_update, SLE_INT32),
+		SLEG_STRUCTLIST(SlLinkgraphEdge),
+	};
+
+	void Save(LinkGraph *lg) const override
+	{
+		_linkgraph = lg;
+
+		for (NodeID from = 0; from < lg->Size(); ++from) {
+			_linkgraph_from = from;
+			SlObject(&lg->nodes[from], this->GetDescription());
+		}
+	}
+
+	void Load(LinkGraph *lg) const override
+	{
+		_linkgraph = lg;
+
+		lg->Init(_num_nodes);
+		for (NodeID from = 0; from < _num_nodes; ++from) {
+			_linkgraph_from = from;
+			SlObject(&lg->nodes[from], this->GetDescription());
+		}
+	}
+};
 
 /**
  * Get a SaveLoad array for a link graph.
@@ -32,11 +105,35 @@ SaveLoadTable GetLinkGraphDesc()
 		 SLE_VAR(LinkGraph, last_compression, SLE_INT32),
 		SLEG_VAR(_num_nodes,                  SLE_UINT16),
 		 SLE_VAR(LinkGraph, cargo,            SLE_UINT8),
+		SLEG_STRUCTLIST(SlLinkgraphNode),
 	};
 	return link_graph_desc;
 }
 
 /**
+ * Proxy to reuse LinkGraph to save/load a LinkGraphJob.
+ * One of the members of a LinkGraphJob is a LinkGraph, but SLEG_STRUCT()
+ * doesn't allow us to select a member. So instead, we add a bit of glue to
+ * accept a LinkGraphJob, get the LinkGraph, and use that to call the
+ * save/load routines for a regular LinkGraph.
+ */
+class SlLinkgraphJobProxy : public DefaultSaveLoadHandler<SlLinkgraphJobProxy, LinkGraphJob> {
+public:
+	inline static const SaveLoad description[] = {{}}; // Needed to keep DefaultSaveLoadHandler happy.
+	SaveLoadTable GetDescription() const override { return GetLinkGraphDesc(); }
+
+	void Save(LinkGraphJob *lgj) const override
+	{
+		SlObject(const_cast<LinkGraph *>(&lgj->Graph()), GetLinkGraphDesc());
+	}
+
+	void Load(LinkGraphJob *lgj) const override
+	{
+		SlObject(const_cast<LinkGraph *>(&lgj->Graph()), GetLinkGraphDesc());
+	}
+};
+
+/**
  * Get a SaveLoad array for a link graph job. The settings struct is derived from
  * the global settings saveload array. The exact entries are calculated when the function
  * is called the first time.
@@ -53,6 +150,7 @@ SaveLoadTable GetLinkGraphJobDesc()
 	static const SaveLoad job_desc[] = {
 		SLE_VAR(LinkGraphJob, join_date,        SLE_INT32),
 		SLE_VAR(LinkGraphJob, link_graph.index, SLE_UINT16),
+		SLEG_STRUCT(SlLinkgraphJobProxy),
 	};
 
 	/* The member offset arithmetic below is only valid if the types in question
@@ -93,56 +191,6 @@ SaveLoadTable GetLinkGraphScheduleDesc()
 	return schedule_desc;
 }
 
-/* Edges and nodes are saved in the correct order, so we don't need to save their IDs. */
-
-/**
- * SaveLoad desc for a link graph node.
- */
-static const SaveLoad _node_desc[] = {
-	SLE_CONDVAR(Node, xy,          SLE_UINT32, SLV_191, SL_MAX_VERSION),
-	    SLE_VAR(Node, supply,      SLE_UINT32),
-	    SLE_VAR(Node, demand,      SLE_UINT32),
-	    SLE_VAR(Node, station,     SLE_UINT16),
-	    SLE_VAR(Node, last_update, SLE_INT32),
-};
-
-/**
- * SaveLoad desc for a link graph edge.
- */
-static const SaveLoad _edge_desc[] = {
-	SLE_CONDNULL(4, SL_MIN_VERSION, SLV_191), // distance
-	     SLE_VAR(Edge, capacity,                 SLE_UINT32),
-	     SLE_VAR(Edge, usage,                    SLE_UINT32),
-	     SLE_VAR(Edge, last_unrestricted_update, SLE_INT32),
-	 SLE_CONDVAR(Edge, last_restricted_update,   SLE_INT32, SLV_187, SL_MAX_VERSION),
-	     SLE_VAR(Edge, next_edge,                SLE_UINT16),
-};
-
-/**
- * Save/load a link graph.
- * @param lg Link graph to be saved or loaded.
- */
-void SaveLoad_LinkGraph(LinkGraph &lg)
-{
-	uint16 size = lg.Size();
-	for (NodeID from = 0; from < size; ++from) {
-		Node *node = &lg.nodes[from];
-		SlObject(node, _node_desc);
-		if (IsSavegameVersionBefore(SLV_191)) {
-			/* We used to save the full matrix ... */
-			for (NodeID to = 0; to < size; ++to) {
-				SlObject(&lg.edges[from][to], _edge_desc);
-			}
-		} else {
-			/* ... but as that wasted a lot of space we save a sparse matrix now. */
-			for (NodeID to = from; to != INVALID_NODE; to = lg.edges[from][to].next_edge) {
-				if (to >= size) SlErrorCorrupt("Link graph structure overflow");
-				SlObject(&lg.edges[from][to], _edge_desc);
-			}
-		}
-	}
-}
-
 /**
  * Spawn the threads for running link graph calculations.
  * Has to be done after loading as the cargo classes might have changed.
@@ -174,24 +222,15 @@ void AfterLoadLinkGraphs()
 }
 
 /**
- * Save a link graph.
- * @param lg LinkGraph to be saved.
- */
-static void DoSave_LGRP(LinkGraph *lg)
-{
-	_num_nodes = lg->Size();
-	SlObject(lg, GetLinkGraphDesc());
-	SaveLoad_LinkGraph(*lg);
-}
-
-/**
  * Save all link graphs.
  */
 static void Save_LGRP()
 {
 	for (LinkGraph *lg : LinkGraph::Iterate()) {
+		_num_nodes = lg->Size();
+
 		SlSetArrayIndex(lg->index);
-		SlAutolength((AutolengthProc*)DoSave_LGRP, lg);
+		SlObject(lg, GetLinkGraphDesc());
 	}
 }
 
@@ -202,37 +241,21 @@ static void Load_LGRP()
 {
 	int index;
 	while ((index = SlIterateArray()) != -1) {
-		if (!LinkGraph::CanAllocateItem()) {
-			/* Impossible as they have been present in previous game. */
-			NOT_REACHED();
-		}
 		LinkGraph *lg = new (index) LinkGraph();
 		SlObject(lg, GetLinkGraphDesc());
-		lg->Init(_num_nodes);
-		SaveLoad_LinkGraph(*lg);
 	}
 }
 
 /**
- * Save a link graph job.
- * @param lgj LinkGraphJob to be saved.
- */
-static void DoSave_LGRJ(LinkGraphJob *lgj)
-{
-	SlObject(lgj, GetLinkGraphJobDesc());
-	_num_nodes = lgj->Size();
-	SlObject(const_cast<LinkGraph *>(&lgj->Graph()), GetLinkGraphDesc());
-	SaveLoad_LinkGraph(const_cast<LinkGraph &>(lgj->Graph()));
-}
-
-/**
  * Save all link graph jobs.
  */
 static void Save_LGRJ()
 {
 	for (LinkGraphJob *lgj : LinkGraphJob::Iterate()) {
+		_num_nodes = lgj->Size();
+
 		SlSetArrayIndex(lgj->index);
-		SlAutolength((AutolengthProc*)DoSave_LGRJ, lgj);
+		SlObject(lgj, GetLinkGraphJobDesc());
 	}
 }
 
@@ -243,16 +266,8 @@ static void Load_LGRJ()
 {
 	int index;
 	while ((index = SlIterateArray()) != -1) {
-		if (!LinkGraphJob::CanAllocateItem()) {
-			/* Impossible as they have been present in previous game. */
-			NOT_REACHED();
-		}
 		LinkGraphJob *lgj = new (index) LinkGraphJob();
 		SlObject(lgj, GetLinkGraphJobDesc());
-		LinkGraph &lg = const_cast<LinkGraph &>(lgj->Graph());
-		SlObject(&lg, GetLinkGraphDesc());
-		lg.Init(_num_nodes);
-		SaveLoad_LinkGraph(lg);
 	}
 }