EngineSettings: Add validation to XP table thresholds

This checks to see if a given XP threshold is less than any previous
levels. If it is, the threshold is set to the highest value plus one.

RELEASE_NOTES.txt

@@ -72,6 +72,7 @@ Engine fixes:
 * The text for dialog options now respects the 'font_dialog' property in menus/talker.txt.
 * Fixed books not closing properly when trying to load another book with an invalid filename.
 * Fixed combat text being shown for zero damage reflect.
+* Added validation to player XP table parsing to ensure that XP thresholds are not less than those for previous levels.
 * Android: Fix 'Flare' directory not being automatically created.
 * Android: Added a dialog to direct the player to the wiki page for installing if no game data is found.
 

src/EngineSettings.cpp

@@ -1081,11 +1081,28 @@ void EngineSettings::XPTable::load() {
 					xp_table.resize(lvl_id);
 
 				xp_table[lvl_id - 1] = lvl_xp;
+
+				// validate that XP is greater than previous levels
+				// corrections are done after then entire table is loaded
+				for (size_t i = 0; i < lvl_id - 1; ++i) {
+					if (xp_table[lvl_id - 1] <= xp_table[i]) {
+						infile.error("EngineSettings: XP for level %u is less than previous levels.", lvl_id);
+						break;
+					}
+				}
 			}
 		}
 		infile.close();
 	}
 
+	// set invalid XP thresolds to valid values
+	for (size_t i = 1; i < xp_table.size(); ++i) {
+		if (xp_table[i] <= xp_table[i-1]) {
+			xp_table[i] = xp_table[i-1] + 1;
+			Utils::logInfo("EngineSettings: Setting XP for level %u to %lu.", i+1, xp_table[i]);
+		}
+	}
+
 	if (xp_table.empty()) {
 		Utils::logError("EngineSettings: No XP table defined.");
 		xp_table.push_back(0);

src/Version.cpp

@@ -30,7 +30,7 @@ FLARE.  If not, see http://www.gnu.org/licenses/
 
 #include <SDL.h>
 
-Version VersionInfo::ENGINE(1, 14, 90);
+Version VersionInfo::ENGINE(1, 14, 91);
 Version VersionInfo::MIN(0, 0, 0);
 Version VersionInfo::MAX(USHRT_MAX, USHRT_MAX, USHRT_MAX);