Use a circular buffer for getReturnBuffer because StringStack's would get clobbered too quickly

Engine/source/console/compiledEval.cpp

@@ -41,6 +41,7 @@
 #include "core/frameAllocator.h"
 
 #include "console/codeInterpreter.h"
+#include "console/returnBuffer.h"
 
 #ifndef TORQUE_TGB_ONLY
 #include "materials/materialDefinition.h"
@@ -101,17 +102,17 @@ F64 consoleStringToNumber(const char *str, StringTableEntry file, U32 line)
 
 namespace Con
 {
+   ReturnBuffer retBuffer;
 
    char *getReturnBuffer(U32 bufferSize)
-
    {
-      return STR.getReturnBuffer(bufferSize);
+      return retBuffer.getBuffer(bufferSize);
    }
 
    char *getReturnBuffer(const char *stringToCopy)
    {
       U32 len = dStrlen(stringToCopy) + 1;
-      char *ret = STR.getReturnBuffer(len);
+      char *ret = retBuffer.getBuffer(len);
       dMemcpy(ret, stringToCopy, len);
       return ret;
    }
@@ -119,7 +120,7 @@ namespace Con
    char* getReturnBuffer(const String& str)
    {
       const U32 size = str.size();
-      char* ret = STR.getReturnBuffer(size);
+      char* ret = retBuffer.getBuffer(size);
       dMemcpy(ret, str.c_str(), size);
       return ret;
    }

Engine/source/console/returnBuffer.cpp

@@ -0,0 +1,83 @@
+//-----------------------------------------------------------------------------
+// Copyright (c) 2012 GarageGames, LLC
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//-----------------------------------------------------------------------------
+
+#include "returnBuffer.h"
+
+ReturnBuffer::ReturnBuffer()
+{
+   mBuffer = nullptr;
+   mBufferSize = 0;
+   mStart = 0;
+
+   //Decent starting alloc of ~1 page = 4kb
+   ensureSize(4 * 1024);
+}
+
+ReturnBuffer::~ReturnBuffer()
+{
+   if (mBuffer)
+   {
+      dFree(mBuffer);
+   }
+}
+
+void ReturnBuffer::ensureSize(U32 newSize)
+{
+   //Round up to nearest multiple of 16 bytes
+   if (newSize & 0xF)
+   {
+      newSize = (newSize & ~0xF) + 0x10;
+   }
+   if (mBuffer == NULL)
+   {
+      //First alloc
+      mBuffer = (char *)dMalloc(newSize * sizeof(char));
+      mBufferSize = newSize;
+   }
+   else if (mBufferSize < newSize)
+   {
+      //Just use the expected size
+      mBuffer = (char *)dRealloc(mBuffer, newSize * sizeof(char));
+      mBufferSize = newSize;
+   }
+}
+
+char *ReturnBuffer::getBuffer(U32 size, U32 alignment)
+{
+   ensureSize(size);
+
+   //Align the start if necessary
+   if (mStart % alignment != 0)
+   {
+      mStart += alignment - (mStart % alignment);
+   }
+
+   if (size + mStart > mBufferSize)
+   {
+      //Restart
+      mStart = 0;
+   }
+   char *buffer = mBuffer + mStart;
+   mStart += size;
+
+   return buffer;
+}

Engine/source/console/returnBuffer.h

@@ -0,0 +1,49 @@
+//-----------------------------------------------------------------------------
+// Copyright (c) 2012 GarageGames, LLC
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//-----------------------------------------------------------------------------
+
+#ifndef _RETURNBUFFER_H_
+#define _RETURNBUFFER_H_
+
+#ifndef _PLATFORM_H_
+   #include <platform/platform.h>
+#endif
+
+/// Simple circular buffer class for temporary return storage.
+class ReturnBuffer
+{
+   char *mBuffer;
+   U32 mBufferSize;
+   U32 mStart;
+
+   /// Possibly expand the buffer to be larger than newSize
+   void ensureSize(U32 newSize);
+
+public:
+   ReturnBuffer();
+   ~ReturnBuffer();
+
+   /// Get a temporary buffer with a given size (and alignment)
+   /// @note The buffer will be re-used so do not consider it permanent
+   char *getBuffer(U32 size, U32 alignment = 16);
+};
+
+#endif //_RETURNBUFFER_H_