Change: store length of SL_STRUCTLIST in the savegame

This wasn't consistently done, and often variables were used that
were read by an earlier blob. By moving it next to the struct
itself, the code becomes a bit more self-contained and easier to
read.

Additionally, this allows for external tooling to know how many
structs to expect, instead of having to know where to find the
length-field or a hard-coded value that can change at any moment.

1 files changed, 39 insertions, 13 deletions

diff --git a/src/saveload/company_sl.cpp b/src/saveload/company_sl.cpp
index 550816a07..880fc9e89 100644
--- a/src/saveload/company_sl.cpp
+++ b/src/saveload/company_sl.cpp
@@ -372,8 +372,19 @@ public:
 
 class SlCompanyOldEconomy : public SlCompanyEconomy {
 public:
-	void GenericSaveLoad(CompanyProperties *c) const
+	void Save(CompanyProperties *c) const override
+	{
+		SlSetStructListLength(c->num_valid_stat_ent);
+		for (int i = 0; i < c->num_valid_stat_ent; i++) {
+			SlObject(&c->old_economy[i], this->GetDescription());
+		}
+	}
+
+	void Load(CompanyProperties *c) const override
 	{
+		if (!IsSavegameVersionBefore(SLV_SAVELOAD_LIST_LENGTH)) {
+			c->num_valid_stat_ent = (uint8)SlGetStructListLength(UINT8_MAX);
+		}
 		if (c->num_valid_stat_ent > lengthof(c->old_economy)) SlErrorCorrupt("Too many old economy entries");
 
 		for (int i = 0; i < c->num_valid_stat_ent; i++) {
@@ -381,10 +392,7 @@ public:
 		}
 	}
 
-	void Save(CompanyProperties *c) const override { this->GenericSaveLoad(c); }
-	void Load(CompanyProperties *c) const override { this->GenericSaveLoad(c); }
-	void LoadCheck(CompanyProperties *c) const override { this->GenericSaveLoad(c); }
-	void FixPointers(CompanyProperties *c) const override { this->GenericSaveLoad(c); }
+	void LoadCheck(CompanyProperties *c) const override { this->Load(c); }
 };
 
 class SlCompanyLiveries : public DefaultSaveLoadHandler<SlCompanyLiveries, CompanyProperties> {
@@ -395,12 +403,33 @@ public:
 		SLE_CONDVAR(Livery, colour2, SLE_UINT8, SLV_34, SL_MAX_VERSION),
 	};
 
-	void GenericSaveLoad(CompanyProperties *c) const
+	/**
+	 * Get the number of liveries used by this savegame version.
+	 * @return The number of liveries used by this savegame version.
+	 */
+	size_t GetNumLiveries() const
 	{
-		int num_liveries = IsSavegameVersionBefore(SLV_63) ? LS_END - 4 : (IsSavegameVersionBefore(SLV_85) ? LS_END - 2: LS_END);
+		if (IsSavegameVersionBefore(SLV_63)) return LS_END - 4;
+		if (IsSavegameVersionBefore(SLV_85)) return LS_END - 2;
+		if (IsSavegameVersionBefore(SLV_SAVELOAD_LIST_LENGTH)) return LS_END;
+		/* Read from the savegame how long the list is. */
+		return SlGetStructListLength(LS_END);
+	}
+
+	void Save(CompanyProperties *c) const override
+	{
+		SlSetStructListLength(LS_END);
+		for (int i = 0; i < LS_END; i++) {
+			SlObject(&c->livery[i], this->GetDescription());
+		}
+	}
+
+	void Load(CompanyProperties *c) const override
+	{
+		size_t num_liveries = this->GetNumLiveries();
 		bool update_in_use = IsSavegameVersionBefore(SLV_GROUP_LIVERIES);
 
-		for (int i = 0; i < num_liveries; i++) {
+		for (size_t i = 0; i < num_liveries; i++) {
 			SlObject(&c->livery[i], this->GetDescription());
 			if (update_in_use && i != LS_DEFAULT) {
 				if (c->livery[i].in_use == 0) {
@@ -426,10 +455,7 @@ public:
 		}
 	}
 
-	void Save(CompanyProperties *c) const override { this->GenericSaveLoad(c); }
-	void Load(CompanyProperties *c) const override { this->GenericSaveLoad(c); }
-	void LoadCheck(CompanyProperties *c) const override { this->GenericSaveLoad(c); }
-	void FixPointers(CompanyProperties *c) const override { this->GenericSaveLoad(c); }
+	void LoadCheck(CompanyProperties *c) const override { this->Load(c); }
 };
 
 /* Save/load of companies */
@@ -467,7 +493,7 @@ static const SaveLoad _company_desc[] = {
 
 	    SLE_ARR(CompanyProperties, share_owners,          SLE_UINT8, 4),
 
-	    SLE_VAR(CompanyProperties, num_valid_stat_ent,    SLE_UINT8),
+	SLE_CONDVAR(CompanyProperties, num_valid_stat_ent,    SLE_UINT8,                   SL_MIN_VERSION, SLV_SAVELOAD_LIST_LENGTH),
 
 	    SLE_VAR(CompanyProperties, months_of_bankruptcy,  SLE_UINT8),
 	SLE_CONDVAR(CompanyProperties, bankrupt_asked,        SLE_FILE_U8  | SLE_VAR_U16,  SL_MIN_VERSION, SLV_104),