Saveload: Add corresponding upstream version to SLXI chunk

src/openttd.cpp

@@ -310,6 +310,7 @@ static void WriteSavegameInfo(const char *name)
 {
 	extern SaveLoadVersion _sl_version;
 	extern std::string _sl_xv_version_label;
+	extern uint16 _sl_xv_upstream_version;
 	uint32 last_ottd_rev = 0;
 	byte ever_modified = 0;
 	bool removed_newgrfs = false;
@@ -331,6 +332,9 @@ static void WriteSavegameInfo(const char *name)
 	if (!_sl_xv_version_label.empty()) {
 		p += seprintf(p, lastof(buf), "    Version label: %s\n", _sl_xv_version_label.c_str());
 	}
+	if (_sl_xv_upstream_version != SL_MIN_VERSION) {
+		p += seprintf(p, lastof(buf), "    Upstream version: %u\n", _sl_xv_upstream_version);
+	}
 	for (size_t i = 0; i < XSLFI_SIZE; i++) {
 		if (_sl_xv_feature_versions[i] > 0) {
 			p += seprintf(p, lastof(buf), "    Feature: %s = %d\n", SlXvGetFeatureName((SlXvFeatureIndex) i), _sl_xv_feature_versions[i]);

src/saveload/extended_ver_sl.cpp

@@ -60,16 +60,20 @@ bool _sl_maybe_chillpp;                                        ///< is this poss
 bool _sl_upstream_mode;                                        ///< load game using upstream loader
 std::vector<uint32> _sl_xv_discardable_chunk_ids;              ///< list of chunks IDs which we can discard if no chunk loader exists
 std::string _sl_xv_version_label;                              ///< optional SLXI version label
+SaveLoadVersion _sl_xv_upstream_version;                       ///< optional SLXI upstream version
 
 static const uint32 _sl_xv_slxi_chunk_version = 0;             ///< current version of SLXI chunk
 
 static void loadVL(const SlxiSubChunkInfo *info, uint32 length);
 static uint32 saveVL(const SlxiSubChunkInfo *info, bool dry_run);
+static void loadUV(const SlxiSubChunkInfo *info, uint32 length);
+static uint32 saveUV(const SlxiSubChunkInfo *info, bool dry_run);
 static void loadLC(const SlxiSubChunkInfo *info, uint32 length);
 static uint32 saveLC(const SlxiSubChunkInfo *info, bool dry_run);
 
 const SlxiSubChunkInfo _sl_xv_sub_chunk_infos[] = {
 	{ XSLFI_VERSION_LABEL,          XSCF_IGNORABLE_ALL,       1,   1, "version_label",             saveVL,  loadVL,  nullptr        },
+	{ XSLFI_UPSTREAM_VERSION,       XSCF_NULL,                1,   1, "upstream_version",          saveUV,  loadUV,  nullptr        },
 	{ XSLFI_TRACE_RESTRICT,         XSCF_NULL,               15,  15, "tracerestrict",             nullptr, nullptr, "TRRM,TRRP,TRRS" },
 	{ XSLFI_TRACE_RESTRICT_OWNER,   XSCF_NULL,                1,   1, "tracerestrict_owner",       nullptr, nullptr, nullptr        },
 	{ XSLFI_TRACE_RESTRICT_ORDRCND, XSCF_NULL,                4,   4, "tracerestrict_order_cond",  nullptr, nullptr, nullptr        },
@@ -254,6 +258,7 @@ void SlXvResetState()
 	_sl_xv_discardable_chunk_ids.clear();
 	std::fill(_sl_xv_feature_versions.begin(), _sl_xv_feature_versions.end(), 0);
 	_sl_xv_version_label.clear();
+	_sl_xv_upstream_version = SL_MIN_VERSION;
 }
 
 /**
@@ -695,6 +700,23 @@ static uint32 saveVL(const SlxiSubChunkInfo *info, bool dry_run)
 	return static_cast<uint32>(length);
 }
 
+static void loadUV(const SlxiSubChunkInfo *info, uint32 length)
+{
+	if (length == 2) {
+		_sl_xv_upstream_version = (SaveLoadVersion)SlReadUint16();
+		DEBUG(sl, 2, "SLXI upstream version: %u", _sl_xv_upstream_version);
+	} else {
+		DEBUG(sl, 1, "SLXI chunk: feature: '%s', version: %d, has data of wrong length: %u", info->name, _sl_xv_feature_versions[info->index], length);
+		ReadBuffer::GetCurrent()->SkipBytes(length);
+	}
+}
+
+static uint32 saveUV(const SlxiSubChunkInfo *info, bool dry_run)
+{
+	if (!dry_run) SlWriteUint16(SL_MAX_VERSION - 1);
+	return 2;
+}
+
 static void loadLC(const SlxiSubChunkInfo *info, uint32 length)
 {
 	if (length == 1) {

src/saveload/extended_ver_sl.h

@@ -24,6 +24,7 @@ enum SaveLoadVersion : uint16;
 enum SlXvFeatureIndex {
 	XSLFI_NULL                          = 0,      ///< Unused value, to indicate that no extended feature test is in use
 	XSLFI_VERSION_LABEL,                          ///< Version label
+	XSLFI_UPSTREAM_VERSION,                       ///< Corresponding upstream savegame version
 	XSLFI_TRACE_RESTRICT,                         ///< Trace restrict
 	XSLFI_TRACE_RESTRICT_OWNER,                   ///< Trace restrict: train owner test
 	XSLFI_TRACE_RESTRICT_ORDRCND,                 ///< Trace restrict: slot conditional order