vulkan-wsi-layer/util/custom_allocator.cpp

/*
 * Copyright (c) 2020-2021 Arm Limited.
 *
 * SPDX-License-Identifier: MIT
 *
 * 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 "custom_allocator.hpp"
#include "macros.hpp"
#include <vulkan/vulkan.h>

namespace util
{

VWL_VKAPI_CALL(void *) default_allocation(void *, size_t size, size_t, VkSystemAllocationScope) VWL_API_POST
{
   return malloc(size);
}

VWL_VKAPI_CALL(void *)
default_reallocation(void *, void *pOriginal, size_t size, size_t, VkSystemAllocationScope) VWL_API_POST
{
   return realloc(pOriginal, size);
}

VWL_VKAPI_CALL(void) default_free(void *, void *pMemory) VWL_API_POST
{
   free(pMemory);
}

const allocator& allocator::get_generic()
{
   static allocator generic{ VK_SYSTEM_ALLOCATION_SCOPE_COMMAND, nullptr };
   return generic;
}

allocator::allocator(const allocator &other, VkSystemAllocationScope new_scope, const VkAllocationCallbacks *callbacks)
   : allocator{ new_scope, callbacks == nullptr ? other.get_original_callbacks() : callbacks }
{
}

/* If callbacks is already populated by vulkan then use those specified as default. */
allocator::allocator(VkSystemAllocationScope scope, const VkAllocationCallbacks *callbacks)
{
   m_scope = scope;
   if (callbacks != nullptr)
   {
      m_callbacks = *callbacks;
   }
   else
   {
      m_callbacks = {};
      m_callbacks.pfnAllocation = default_allocation;
      m_callbacks.pfnReallocation = default_reallocation;
      m_callbacks.pfnFree = default_free;
   }
}

const VkAllocationCallbacks *allocator::get_original_callbacks() const
{
   return m_callbacks.pfnAllocation == default_allocation ? nullptr : &m_callbacks;
}

} /* namespace util */