Add "special events" log. Add console command, include in crash logs.

src/console_cmds.cpp

@@ -2250,6 +2250,19 @@ DEF_CONSOLE_CMD(ConDumpCommandLog)
 	return true;
 }
 
+DEF_CONSOLE_CMD(ConDumpSpecialEventsLog)
+{
+	if (argc == 0) {
+		IConsoleHelp("Dump log of special events.");
+		return true;
+	}
+
+	char buffer[32768];
+	DumpSpecialEventsLog(buffer, lastof(buffer));
+	PrintLineByLine(buffer);
+	return true;
+}
+
 DEF_CONSOLE_CMD(ConDumpDesyncMsgLog)
 {
 	if (argc == 0) {
@@ -3470,6 +3483,7 @@ void IConsoleStdLibRegister()
 
 	IConsole::CmdRegister("getfulldate",             ConGetFullDate,      nullptr, true);
 	IConsole::CmdRegister("dump_command_log",        ConDumpCommandLog,   nullptr, true);
+	IConsole::CmdRegister("dump_special_events_log", ConDumpSpecialEventsLog, nullptr, true);
 	IConsole::CmdRegister("dump_desync_msgs",        ConDumpDesyncMsgLog, nullptr, true);
 	IConsole::CmdRegister("dump_inflation",          ConDumpInflation,    nullptr, true);
 	IConsole::CmdRegister("dump_cpdp_stats",         ConDumpCpdpStats,    nullptr, true);

src/crashlog.cpp

@@ -411,6 +411,8 @@ char *CrashLog::LogCommandLog(char *buffer, const char *last) const
 {
 	buffer = DumpCommandLog(buffer, last);
 	buffer += seprintf(buffer, last, "\n");
+	buffer = DumpSpecialEventsLog(buffer, last);
+	buffer += seprintf(buffer, last, "\n");
 	return buffer;
 }
 

src/economy.cpp

@@ -590,6 +590,12 @@ void ChangeOwnershipOfCompanyItems(Owner old_owner, Owner new_owner)
 
 	cur_company.Restore();
 
+	if (new_owner != INVALID_OWNER) {
+		AppendSpecialEventsLogEntry(stdstr_fmt("Company merge: old: %u, new %u", old_owner, new_owner));
+	} else {
+		AppendSpecialEventsLogEntry(stdstr_fmt("Company deletion: old: %u", old_owner));
+	}
+
 	RegisterGameEvents(new_owner != INVALID_OWNER ? GEF_COMPANY_MERGE : GEF_COMPANY_DELETE);
 
 	MarkWholeScreenDirty();

src/event_logs.cpp

@@ -10,6 +10,10 @@
 #include "stdafx.h"
 #include "event_logs.h"
 #include "string_func.h"
+#include "date_func.h"
+#include "company_func.h"
+#include <array>
+#include <string>
 
 #include "safeguards.h"
 
@@ -35,3 +39,66 @@ char *DumpGameEventFlags(GameEventFlags events, char *b, const char *last)
 	dump('v', GEF_VIRT_TRAIN);
 	return b;
 }
+
+struct SpecialEventLogEntry {
+	std::string msg;
+	Date date;
+	DateFract date_fract;
+	uint8 tick_skip_counter;
+	CompanyID current_company;
+	CompanyID local_company;
+
+	SpecialEventLogEntry() { }
+
+	SpecialEventLogEntry(std::string msg)
+			: msg(std::move(msg)), date(_date), date_fract(_date_fract), tick_skip_counter(_tick_skip_counter),
+			current_company(_current_company), local_company(_local_company) { }
+};
+
+struct SpecialEventLog {
+	std::array<SpecialEventLogEntry, 64> log;
+	unsigned int count = 0;
+	unsigned int next = 0;
+
+	void Reset()
+	{
+		this->count = 0;
+		this->next = 0;
+	}
+};
+
+static SpecialEventLog _special_event_log;
+
+void AppendSpecialEventsLogEntry(std::string message)
+{
+	_special_event_log.log[_special_event_log.next] = SpecialEventLogEntry(std::move(message));
+	_special_event_log.next = (_special_event_log.next + 1) % _special_event_log.log.size();
+	_special_event_log.count++;
+}
+
+char *DumpSpecialEventsLog(char *buffer, const char *last)
+{
+	const unsigned int count = std::min<unsigned int>(_special_event_log.count, 64);
+	buffer += seprintf(buffer, last, "Special Events Log:\n Showing most recent %u of %u events\n", count, _special_event_log.count);
+
+	unsigned int log_index = _special_event_log.next;
+	for (unsigned int i = 0 ; i < count; i++) {
+		if (log_index > 0) {
+			log_index--;
+		} else {
+			log_index = (uint)_special_event_log.log.size() - 1;
+		}
+		const SpecialEventLogEntry &entry = _special_event_log.log[log_index];
+
+		YearMonthDay ymd;
+		ConvertDateToYMD(entry.date, &ymd);
+		buffer += seprintf(buffer, last, " %3u | %4i-%02i-%02i, %2i, %3i | cc: %3u, lc: %3u | %s\n",
+				i, ymd.year, ymd.month + 1, ymd.day, entry.date_fract, entry.tick_skip_counter, (uint) entry.current_company, (uint) entry.local_company, entry.msg.c_str());
+	}
+	return buffer;
+}
+
+void ClearSpecialEventsLog()
+{
+	_special_event_log.Reset();
+}

src/event_logs.h

@@ -39,4 +39,8 @@ char *DumpGameEventFlags(GameEventFlags events, char *b, const char *last);
 
 extern time_t _game_load_time;
 
+void AppendSpecialEventsLogEntry(std::string message);
+char *DumpSpecialEventsLog(char *buffer, const char *last);
+void ClearSpecialEventsLog();
+
 #endif /* EVENT_LOGS_H */

src/misc.cpp

@@ -79,6 +79,7 @@ void InitializeGame(uint size_x, uint size_y, bool reset_date, bool reset_settin
 
 	ViewportMapClearTunnelCache();
 	ClearCommandLog();
+	ClearSpecialEventsLog();
 	ClearDesyncMsgLog();
 
 	_pause_mode = PM_UNPAUSED;

src/openttd.cpp

@@ -457,6 +457,7 @@ static void ShutdownGame()
 	ClearVehicleTickCaches();
 	InvalidateTemplateReplacementImages();
 	ClearCommandLog();
+	ClearSpecialEventsLog();
 	ClearDesyncMsgLog();
 
 	_loaded_local_company = COMPANY_SPECTATOR;

src/saveload/afterload.cpp

@@ -4031,6 +4031,7 @@ bool AfterLoadGame()
 void ReloadNewGRFData()
 {
 	RegisterGameEvents(GEF_RELOAD_NEWGRF);
+	AppendSpecialEventsLogEntry("NewGRF reload");
 
 	RailTypeLabel rail_type_label_map[RAILTYPE_END];
 	for (RailType rt = RAILTYPE_BEGIN; rt != RAILTYPE_END; rt++) {