giant batch BOOOOM

Minecraft.Client/Level/MultiPlayerLevel.cpp

@@ -702,12 +702,12 @@ void MultiPlayerLevel::animateTickDoWork()
 		for( AUTO_VAR(it, chunksToAnimate.begin()); it != chunksToAnimate.end(); it++ )
 		{
 			int packed = *it;
-			int cx = ( packed << 8 ) >> 24;
-			int cy = ( packed << 16 ) >> 24;
-			int cz = ( packed << 24 ) >> 24;
-			cx <<= 3;
-			cy <<= 3;
-			cz <<= 3;
+			// 4jcraft changed the extraction logic to be safe
+			// constantly shifting a signed integer
+			int cx = (int8_t)(packed >> 16) * 8;
+			int cy = (int8_t)(packed >> 8) * 8;
+			int cz = (int8_t)packed * 8;
+
 			int x = cx + random->nextInt(8);
 			int y = cy + random->nextInt(8);
 			int z = cz + random->nextInt(8);

Minecraft.Client/Level/ServerLevel.cpp

@@ -475,7 +475,8 @@ void ServerLevel::tickTiles()
 		// 4J - changes here brought forrward from 1.2.3
 		if (random->nextInt(16) == 0)
 		{
-            randValue = randValue * 3 + addend;
+			//4jcraft added cast to unsigned
+            randValue = (unsigned)randValue * 3 + (unsigned)addend;
             int val = (randValue >> 2);
             int x = (val & 15);
             int z = ((val >> 8) & 15);
@@ -1414,7 +1415,8 @@ int ServerLevel::runUpdate(void* lpParam)
 
 				for (int j = 0; j < 80; j++)
 				{
-					m_randValue[iLev] = m_randValue[iLev] * 3 + m_level[iLev]->addend;
+					// 4jcraft added cast to unsigned
+					m_randValue[iLev] = (unsigned) m_randValue[iLev] * 3 + (unsigned) m_level[iLev]->addend;
 					int val = (m_randValue[iLev] >> 2);
 					int x = (val & 15);
 					if( ( x < minx ) || ( x > maxx ) ) continue;

Minecraft.Client/Platform/Common/Tutorial/Tutorial.cpp

@@ -343,6 +343,9 @@ Tutorial::Tutorial(int iPad, bool isFullTutorial /*= false*/) : m_iPad( iPad )
 	m_bHasTickedOnce = false;
 	m_firstTickTime = 0;
 
+	// 4jcraft added, not initialized
+	m_bSceneIsSplitscreen = false;
+
 	m_lastMessage = NULL;
 
 	lastMessageTime = 0;
@@ -1258,7 +1261,7 @@ void Tutorial::tick()
 	else
 	{
 		// if we've changed mode, we may need to change scene
-		if(m_bSceneIsSplitscreen!=(app.GetLocalPlayerCount()>1))
+		if(m_bSceneIsSplitscreen != (app.GetLocalPlayerCount() > 1))
 		{
 #ifdef _XBOX
 			app.TutorialSceneNavigateBack(m_iPad);

Minecraft.Client/Player/ServerPlayer.cpp

@@ -45,6 +45,9 @@ ServerPlayer::ServerPlayer(MinecraftServer *server, Level *level, const std::wst
 	m_enteredEndExitPortal = false;
 	lastCarried = ItemInstanceArray(5);
 	viewDistance = 10;
+	
+	// 4jcraft added (0 initialized)
+	m_lastDamageSource = eTelemetryChallenges_Unknown;
 
 //    gameMode->player = this;		// 4J - removed to avoid use of shared_from_this in ctor, now set up externally
     this->gameMode = gameMode;
@@ -540,7 +543,7 @@ void ServerPlayer::doTickB(bool ignorePortal)
 
     if (getHealth() != lastSentHealth || lastSentFood != foodData.getFoodLevel() || ((foodData.getSaturationLevel() == 0) != lastFoodSaturationZero))
 	{
-		// 4J Stu - Added m_lastDamageSource for telemetry
+		// 4J Stu - Added m_lastDamageSource for telemetry //4jcraft, nice but you never initialized it
 		connection->send( std::shared_ptr<SetHealthPacket>( new SetHealthPacket(getHealth(), foodData.getFoodLevel(), foodData.getSaturationLevel(), m_lastDamageSource) ) );
         lastSentHealth = getHealth();
 		lastSentFood = foodData.getFoodLevel();

Minecraft.World/AI/Navigation/Node.cpp

@@ -30,7 +30,8 @@ hash(createHash(x, y, z))
 
 int Node::createHash(const int x, const int y, const int z) 
 {
-	return (y & 0xff) | ((x & 0x7fff) << 8) | ((z & 0x7fff) << 24) | ((x < 0) ? 0x0080000000 : 0) | ((z < 0) ? 0x0000008000 : 0);
+	// 4jcraft added cast to higher value to be representable after shift
+	return (y & 0xff) | (((int64_t)x & 0x7fff) << 8) | (((int64_t)z & 0x7fff) << 24) | ((x < 0) ? 0x0080000000 : 0) | ((z < 0) ? 0x0000008000 : 0);
 }
 
 float Node::distanceTo(Node *to) 
@@ -72,4 +73,4 @@ bool Node::inOpenSet()
 std::wstring Node::toString() 
 {
 	return _toString<int>(x) + L", " + _toString<int>(y) + L", " + _toString<int>(z);
-}
+}

Minecraft.World/Network/Packets/ChunkTilesUpdatePacket.cpp

@@ -54,8 +54,9 @@ void ChunkTilesUpdatePacket::read(DataInputStream *dis) //throws IOException
 #ifdef _LARGE_WORLDS
 	xc = dis->readShort();
 	zc = dis->readShort();
-	xc = ( xc << 16 ) >> 16;
-	zc = ( zc << 16 ) >> 16;
+	// 4jcraft changed shift back and forth to a down cast
+	xc = (int16_t) xc;
+	zc = (int16_t) zc;
 #else
 	xc = dis->read();
 	zc = dis->read();

Minecraft.World/Util/JavaIntHash.h

@@ -9,11 +9,12 @@ struct IntKeyHash
 {
 	int operator() (const int &k) const
 	{
-		int h = k;
+		// 4jcraft added h to be unsigned, to not cast it later
+	unsigned int h = k;
         h += ~(h << 9);
-        h ^=  (((unsigned int)h) >> 14);
+        h ^=  (h >> 14);
         h +=  (h << 4);
-        h ^=  (((unsigned int)h) >> 10);
+        h ^=  (h >> 10);
 		return h;
 	}
 };

Minecraft.World/Util/Random.cpp

@@ -88,7 +88,7 @@ int Random::nextInt(int n)
 
 
     if ((n & -n) == n)  // i.e., n is a power of 2
-	// 4jcraft added casts to unsigned
+	// 4jcraft added casts to unsigned (and uint64)
         return (unsigned int)(((__uint64)next(31) * n) >> 31); // 4J Stu - Made __int64 instead of long
 
     int bits, val;
@@ -96,7 +96,8 @@ int Random::nextInt(int n)
 	{
         bits = next(31);
         val = bits % n;
-    } while(bits - val + (n-1) < 0);
+	// 4jcraft added a cast to prevent overflow
+    } while((int64_t) bits - val + (n-1) < 0);
     return val;
 }