Add setting for long-term autosaves

A second set of autosaves for whenever the main set wraps around to 0

src/fios.cpp

@@ -787,7 +787,16 @@ FiosNumberedSaveName::FiosNumberedSaveName(const std::string &prefix) : prefix(p
 */
 std::string FiosNumberedSaveName::Filename()
 {
-	if (++this->number >= _settings_client.gui.max_num_autosaves) this->number = 0;
+	return this->FilenameUsingMaxSaves(_settings_client.gui.max_num_autosaves);
+}
+
+/**
+ * Generate a savegame name and number according to max_saves.
+ * @return A filename in format "<prefix><number>.sav".
+*/
+std::string FiosNumberedSaveName::FilenameUsingMaxSaves(int max_saves)
+{
+	if (++this->number >= max_saves) this->number = 0;
 	return this->FilenameUsingNumber(this->number, "");
 }
 

src/fios.h

@@ -75,6 +75,7 @@ const char *FindScenario(const ContentInfo *ci, bool md5sum);
 struct FiosNumberedSaveName {
 	FiosNumberedSaveName(const std::string &prefix);
 	std::string Filename();
+	std::string FilenameUsingMaxSaves(int max_saves);
 	std::string FilenameUsingNumber(int num, const char *suffix) const;
 	std::string Extension();
 	int GetLastNumber() const { return this->number; }

src/openttd.cpp

@@ -2143,13 +2143,23 @@ FiosNumberedSaveName &GetAutoSaveFiosNumberedSaveName()
 	return _autosave_ctr;
 }
 
+FiosNumberedSaveName &GetLongTermAutoSaveFiosNumberedSaveName()
+{
+	static FiosNumberedSaveName _autosave_lt_ctr("ltautosave");
+	return _autosave_lt_ctr;
+}
+
 /**
  * Create an autosave. The default name is "autosave#.sav". However with
  * the setting 'keep_all_autosave' the name defaults to company-name + date
  */
 static void DoAutosave()
 {
-	DoAutoOrNetsave(GetAutoSaveFiosNumberedSaveName(), true);
+	FiosNumberedSaveName *lt_counter = nullptr;
+	if (_settings_client.gui.max_num_autosaves > 0) {
+		lt_counter = &GetLongTermAutoSaveFiosNumberedSaveName();
+	}
+	DoAutoOrNetsave(GetAutoSaveFiosNumberedSaveName(), true, lt_counter);
 }
 
 /**

src/settings_type.h

@@ -178,6 +178,7 @@ struct GUISettings : public TimeSettings {
 	bool   autosave_on_network_disconnect;   ///< save an autosave when you get disconnected from a network game with an error?
 	uint8  date_format_in_default_names;     ///< should the default savegame/screenshot name use long dates (31th Dec 2008), short dates (31-12-2008) or ISO dates (2008-12-31)
 	byte   max_num_autosaves;                ///< controls how many autosavegames are made before the game starts to overwrite (names them 0 to max_num_autosaves - 1)
+	byte   max_num_lt_autosaves;             ///< controls how many long-term autosavegames are made before the game starts to overwrite (names them 0 to max_num_lt_autosaves - 1)
 	uint8  savegame_overwrite_confirm;       ///< Mode for when to warn about overwriting an existing savegame
 	bool   population_in_label;              ///< show the population of a town in its label?
 	uint8  right_mouse_btn_emulation;        ///< should we emulate right mouse clicking?

src/sl/saveload.cpp

@@ -3722,7 +3722,7 @@ SaveOrLoadResult SaveOrLoad(const std::string &filename, SaveLoadOperation fop,
  * @param counter A reference to the counter variable to be used for rotating the file name.
  * @param netsave Indicates if this is a regular autosave or a netsave.
  */
-void DoAutoOrNetsave(FiosNumberedSaveName &counter, bool threaded)
+void DoAutoOrNetsave(FiosNumberedSaveName &counter, bool threaded, FiosNumberedSaveName *lt_counter)
 {
 	char buf[MAX_PATH];
 
@@ -3731,6 +3731,12 @@ void DoAutoOrNetsave(FiosNumberedSaveName &counter, bool threaded)
 		strecat(buf, counter.Extension().c_str(), lastof(buf));
 	} else {
 		strecpy(buf, counter.Filename().c_str(), lastof(buf));
+		if (lt_counter != nullptr && counter.GetLastNumber() == 0) {
+			std::string lt_path = lt_counter->FilenameUsingMaxSaves(_settings_client.gui.max_num_lt_autosaves);
+			DEBUG(sl, 2, "Renaming autosave '%s' to long-term file '%s'", buf, lt_path.c_str());
+			std::string dir = FioFindDirectory(AUTOSAVE_DIR);
+			rename((dir + buf).c_str(), (dir + lt_path).c_str());
+		}
 	}
 
 	DEBUG(sl, 2, "Autosaving to '%s'", buf);

src/sl/saveload.h

@@ -68,7 +68,7 @@ void WaitTillSaved();
 void ProcessAsyncSaveFinish();
 void DoExitSave();
 
-void DoAutoOrNetsave(FiosNumberedSaveName &counter, bool threaded);
+void DoAutoOrNetsave(FiosNumberedSaveName &counter, bool threaded, FiosNumberedSaveName *lt_counter = nullptr);
 
 SaveOrLoadResult SaveWithFilter(struct SaveFilter *writer, bool threaded, SaveModeFlags flags);
 SaveOrLoadResult LoadWithFilter(struct LoadFilter *reader);

src/table/settings/settings.ini

@@ -5487,6 +5487,14 @@ def      = 16
 min      = 0
 max      = 255
 
+[SDTC_VAR]
+var      = gui.max_num_lt_autosaves
+type     = SLE_UINT8
+flags    = SF_NOT_IN_SAVE | SF_NO_NETWORK_SYNC
+def      = 8
+min      = 0
+max      = 255
+
 [SDTC_OMANY]
 var      = gui.savegame_overwrite_confirm
 type     = SLE_UINT8