gfx/gl/HeapCopyOfStackArray.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /* vim: set ts=8 sts=4 et sw=4 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef HEAPCOPYOFSTACKARRAY_H_
   8 #define HEAPCOPYOFSTACKARRAY_H_
   9
  10 #include "mozilla/Attributes.h"
  11 #include "mozilla/Scoped.h"
  12
  13 #include <string.h>
  14
  15 namespace mozilla {
  16
  17 // Takes a stack array and copies it into a heap buffer.
  18 // Useful to retain the convenience of declaring static arrays, while
  19 // avoiding passing stack pointers to the GL (see bug 1005658).
  20
  21 template <typename ElemType>
  22 class HeapCopyOfStackArray
  23 {
  24 public:
  25   template<size_t N>
  26   HeapCopyOfStackArray(ElemType (&array)[N])
  27     : mArrayLength(N)
  28     , mArrayData(new ElemType[N])
  29   {
  30     memcpy(mArrayData, &array[0], N * sizeof(ElemType));
  31   }
  32
  33   ElemType* Data() const { return mArrayData; }
  34   size_t ArrayLength() const { return mArrayLength; }
  35   size_t ByteLength() const { return mArrayLength * sizeof(ElemType); }
  36
  37 private:
  38   HeapCopyOfStackArray() = delete;
  39   HeapCopyOfStackArray(const HeapCopyOfStackArray&) = delete;
  40
  41   const size_t mArrayLength;
  42   ScopedDeletePtr<ElemType> const mArrayData;
  43 };
  44
  45 }
  46
  47 #endif // HEAPCOPYOFSTACKARRAY_H_