Add extended version tag and feature versions to output of -q.

src/openttd.cpp

@@ -249,7 +249,20 @@ static void WriteSavegameInfo(const char *name)
 	char buf[8192];
 	char *p = buf;
 	p += seprintf(p, lastof(buf), "Name:         %s\n", name);
-	p += seprintf(p, lastof(buf), "Savegame ver: %d\n", _sl_version);
+	const char *type = "";
+	extern bool _sl_is_faked_ext;
+	extern bool _sl_is_ext_version;
+	if (_sl_is_faked_ext) {
+		type = " (fake extended)";
+	} else if (_sl_is_ext_version) {
+		type = " (extended)";
+	}
+	p += seprintf(p, lastof(buf), "Savegame ver: %d%s\n", _sl_version, type);
+	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]);
+		}
+	}
 	p += seprintf(p, lastof(buf), "NewGRF ver:   0x%08X\n", last_ottd_rev);
 	p += seprintf(p, lastof(buf), "Modified:     %d\n", ever_modified);
 

src/saveload/extended_ver_sl.cpp

@@ -86,6 +86,20 @@ bool SlXvIsFeaturePresent(SlXvFeatureIndex feature, uint16 min_version, uint16 m
 	return _sl_xv_feature_versions[feature] >= min_version && _sl_xv_feature_versions[feature] <= max_version;
 }
 
+/**
+ * Returns true if @p feature is present and has a version inclusively bounded by @p min_version and @p max_version
+ */
+const char *SlXvGetFeatureName(SlXvFeatureIndex feature)
+{
+	const SlxiSubChunkInfo *info = _sl_xv_sub_chunk_infos;
+	for (; info->index != XSLFI_NULL; ++info) {
+		if (info->index == feature) {
+			return info->name;
+		}
+	}
+	return "(unknown feature)";
+}
+
 /**
  * Resets all extended feature versions to 0
  */

src/saveload/extended_ver_sl.h

@@ -65,6 +65,8 @@ inline bool SlXvIsFeatureMissing(SlXvFeatureIndex feature)
 	return !SlXvIsFeaturePresent(feature);
 }
 
+const char *SlXvGetFeatureName(SlXvFeatureIndex feature);
+
 /**
  * sub chunk flags, this is saved as-is
  * (XSCF_EXTRA_DATA_PRESENT and XSCF_CHUNK_ID_LIST_PRESENT must only be set by the save code, and read by the load code)