Core/Misc: Add more extensive ByteBuffer exceptions to trace down seemingly random crashes.

src/server/shared/Packets/ByteBuffer.h

@@ -27,22 +27,49 @@
 class ByteBufferException
 {
     public:
-        ByteBufferException(bool _add, size_t _pos, size_t _esize, size_t _size)
+        ByteBufferException(size_t pos, size_t size, size_t valueSize)
-            : add(_add), pos(_pos), esize(_esize), size(_size)
+            : Pos(pos), Size(size), ValueSize(valueSize)
         {
-            PrintPosError();
+            PrintError();
         }
 
-        void PrintPosError() const
+    protected:
+        virtual void PrintError() const = 0;
+    
+        size_t Pos;
+        size_t Size;
+        size_t ValueSize;
+};
+
+class ByteBufferPositionException : public ByteBufferException
+{
+    public:
+        ByteBufferPositionException(bool add, size_t pos, size_t size, size_t valueSize)
+        : ByteBufferException(pos, size, valueSize), _add(add) {}
+
+    protected:
+        void PrintError() const override
         {
-            sLog->outError("Attempted to %s in ByteBuffer (pos: " SIZEFMTD " size: "SIZEFMTD") value with size: " SIZEFMTD,
+            sLog->outError("Attempted to %s value with size: "SIZEFMTD" in ByteBuffer (pos: " SIZEFMTD " size: "SIZEFMTD") " ,
-                (add ? "put" : "get"), pos, size, esize);
+                ValueSize, (_add ? "put" : "get"), Pos, Size);
         }
+
     private:
-        bool add;
+        bool _add;
-        size_t pos;
+};
-        size_t esize;
+
-        size_t size;
+class ByteBufferSourceException : public ByteBufferException
+{
+    public:
+        ByteBufferSourceException(size_t pos, size_t size, size_t valueSize)
+        : ByteBufferException(pos, size, valueSize) {}
+
+    protected: 
+        void PrintError() const override
+        {
+            sLog->outError("Attempted to put a %s in ByteBuffer (pos: "SIZEFMTD" size: "SIZEFMTD")",
+                (ValueSize > 0 ? "NULL-pointer" : "zero-sized value"), Pos, Size);
+        }
 };
 
 class ByteBuffer
@@ -271,7 +298,7 @@ class ByteBuffer
         void read_skip(size_t skip)
         {
             if (_rpos + skip > size())
-                throw ByteBufferException(false, _rpos, skip, size());
+                throw ByteBufferPositionException(false, _rpos, skip, size());
             _rpos += skip;
         }
 
@@ -285,7 +312,7 @@ class ByteBuffer
         template <typename T> T read(size_t pos) const
         {
             if (pos + sizeof(T) > size())
-                throw ByteBufferException(false, pos, sizeof(T), size());
+                throw ByteBufferPositionException(false, pos, sizeof(T), size());
             T val = *((T const*)&_storage[pos]);
             EndianConvert(val);
             return val;
@@ -294,7 +321,7 @@ class ByteBuffer
         void read(uint8 *dest, size_t len)
         {
             if (_rpos  + len > size())
-               throw ByteBufferException(false, _rpos, len, size());
+               throw ByteBufferPositionException(false, _rpos, len, size());
             memcpy(dest, &_storage[_rpos], len);
             _rpos += len;
         }
@@ -302,7 +329,7 @@ class ByteBuffer
         void readPackGUID(uint64& guid)
         {
             if (rpos() + 1 > size())
-                throw ByteBufferException(false, _rpos, 1, size());
+                throw ByteBufferPositionException(false, _rpos, 1, size());
 
             guid = 0;
 
@@ -314,7 +341,7 @@ class ByteBuffer
                 if (guidmark & (uint8(1) << i))
                 {
                     if (rpos() + 1 > size())
-                        throw ByteBufferException(false, _rpos, 1, size());
+                        throw ByteBufferPositionException(false, _rpos, 1, size());
 
                     uint8 bit;
                     (*this) >> bit;
@@ -359,7 +386,10 @@ class ByteBuffer
         void append(const uint8 *src, size_t cnt)
         {
             if (!cnt)
-                return;
+                throw ByteBufferSourceException(_wpos, size(), cnt);
+
+            if (!src)
+                throw ByteBufferSourceException(_wpos, size(), cnt);
 
             ASSERT(size() < 10000000);
 
@@ -407,7 +437,11 @@ class ByteBuffer
         void put(size_t pos, const uint8 *src, size_t cnt)
         {
             if (pos + cnt > size())
-               throw ByteBufferException(true, pos, cnt, size());
+               throw ByteBufferPositionException(true, pos, cnt, size());
+
+            if (!src)
+                throw ByteBufferSourceException(_wpos, size(), cnt);
+
             memcpy(&_storage[pos], src, cnt);
         }